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  • 1
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    The International Collective in Support of Fishworkers (ICSF) | India
    Publikationsdatum: 2022-02-21
    Beschreibung: Yemaya No. 63, dated May 2021, features articles from US, The Netherlands, Myanmar, Senegal, and an article on women in fisheries and human rights. The article from the US by Linda Behnken argues that a growing coalition of small-scale, community-based fishers is calling for the recognition and protection of Alaska’s invaluable coastal fisheries during COVID-19. The article from the Netherlands by Cornelie Quist looks at the challenges facing women engaged in small-scale fishing and supplying fish through retailers and how they found new ways to directly reach consumers. The conversation between Miranda Bout and Cornelie Quist focuses on how they combined new product development with the use of social media to contact their customer base during the pandemic-induced disruption of traditional marketing chains. The article by Elena Finkbeiner, Juno Fitzpatrick and Whitney Yadao-Evans looks at recent media revelations and scientific research that have brought increased attention to human-rights violations and the myriad social issues facing fisheries, but with a disproportionate focus on labour-rights violations at sea and in industrial fishing operations. The systemic inequalities combined with the effects of COVID-19 exacerbated vulnerabilities of women to health risks, food and livelihood security. The article from Senegal by Aby Dia from Lumière Synergie pour le Développement (LSD), in collaboration with WoMin African Alliance, South Africa, narrates the story of traditional women fish processors from the Bargny who have been, for more than a decade, struggling against development projects that jeopardise their environment, health and livelihoods. In order to preserve their livelihoods, women processors in Senegal have come together to oppose the Tosyali steel project. The European Network of Women in Fisheries and Aquaculture in Europe (AKTEA) urges the Office of the Commissioner for the Environment, Oceans and Fisheries to integrate gender into all aspects of European fishing policy. The Profile column looks at how Linda Behnken became a fisher in Alaska and how fishing has shaped her individuality and work. Natalie Sattler says that fishing for halibut, sablefish and salmon from the sparkling waters of the Pacific along with her children and at the same time passion for working with the Alaska Longline Fishermen’s Association and the Alaska Sustainable Fisheries Trust is an immense challenge.
    Beschreibung: Published
    Beschreibung: Refereed
    Schlagwort(e): Fishing Communities ; Women in fisheries ; Gender ; Small-scale fisheries ; Aquaculture ; Fisheries
    Repository-Name: AquaDocs
    Materialart: Book/Monograph/Conference Proceedings
    Format: 12p.
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  • 2
    Publikationsdatum: 2022-06-28
    Beschreibung: Las pesquerías basadas en las agregaciones reproductivas pueden amenazar a especies como los pargos que tienen conductas gregarias durante el período reproductivo. Esta nota ofrece elementos que sugieren la existencia de sitios de agregación no registrados previamente y no protegidos en el Parque Nacional Cayos de San Felipe (PNCSF), región suroccidental de Cuba. La información tradicional obtenida de pescadores locales y trabajadores del parque se corroboró con muestreos cualitativos y cuantitativos de peces de arrecifes y datos de pesquerías locales del 2014. En la época de reproducción de pargos (mayo a julio) se observaron grupos de entre 40-100 ejemplares de Lutjanus cyanopterus, Lutjanus synagris y Lutjanus jocu en los arrecifes de la zona occidental del PNCSF (camellones entre 15-30 m de profundidad cerca del borde de la plataforma). Dentro de esa área, se señalan dos sitios que parecen ser utilizados para agregaciones de predesove, por lo que requieren protección y ser estudiados. Los censos cuantitativos confirmaron que en mayo y junio la zona occidental tiene densidad alta de pargos adultos. También, el pico de captura de estas especies ocurrió en la época reproductiva. Se comprobó que las pesquerías se realizaron durante las migraciones de peces hacia el borde de la plataforma en áreas de la zona occidental del PNCSF, y que más del 60% de los individuos tuvieron gónadas maduras (antes de desovar). Esta información debe incentivar el estudio de las agregaciones de desove en esta región de Cuba, la protección de especies amenazadas y áreas de alta significación ecológica y la implementación de pesquerías sostenibles.
    Beschreibung: Fisheries based on reproductive aggregations can threaten species such as snappers that have gregarious behavior during the reproductive period. This note provides evidence to support the existence of aggregation sites, not previously registered and unprotected, in the National Park San Felipe Keys (NPSFK), southwestern region of Cuba. Traditionalinformation obtained from local fishermen and from the park staff was complemented with qualitative and quantitative fish reef censuses and local fisheries data in 2014. In the reproductive season of snappers (May to July) groups of between 40-100 specimens of Lutjanus cyanopterus, Lutja- nus synagris and Lutjanus jocu were observed in the western area of the NPSFK on the reefs (spoor and grove between 20-30 m deep close to the platform edge). Within that area two sites are indicated that can be used for prespawning aggregation, so they require protection and study. Quanti- tative censuses confirmed that in May and June the western zone has high density of adult snappers. Also, the peak of capture of these snapper species occurred in the reproduc- tive season. It was found that fisheries carried out during fish migrations to the edge of the shelf in areas of the western area of the NPSFK and more than 60% of the individuals had mature gonads (before spawning). This information should promote the study of spawning aggregations in this region of Cuba, the protection of threatened species and areas of high ecological significance and the implementation of sustainable fisheries.
    Beschreibung: Published
    Beschreibung: Refereed
    Schlagwort(e): Región suroccidental de Cuba ; Desove ; Pesquerías ; Migration routes ; Spawning ; Fisheries ; Rutas migraciones
    Repository-Name: AquaDocs
    Materialart: Journal Contribution
    Format: pp.54-65
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  • 3
    Publikationsdatum: 2022-09-14
    Beschreibung: The ICES Workshop on ICES reference points (WKREF2) was tasked review the WKREF1 report and based on the outcome develop updated guidelines for the ICES reference points system and recommendations for ACOM consideration. The WKREF1 report has suggested 5 key recom- mendations to simplify and harmonise the ICES reference points framework representing a ma- jor change to the current guidelines. At WKREF2, we detailed discussions and four key concerns were raised about the proposed approach. The first related to the simplification of rules to define Blim. Around two thirds of category 1 stocks would end up as WKREF1 “Blim Type 2” where Blim would be set as a fraction of B0. The Allee effect or “depensation” maybe more important than previously thought and should be furthered explored for ICES stocks since it has important consequences for Blim. A number of challenges and issues around defining Blim using the current guidelines were documented. Some suggestions on improvement criteria were discussed including using classifiers to define spas- modic stocks and using change point algorithms to address non-stationary productivity regimes. However, further work is need to make these approaches operational and there was no consen- sus that the WKREF1 Blim types should replace the current guidelines. WKREF1 recommended that the FMSY proxy should be based on a biological proxies and should be less than the deterministic FMSY. It was pointed out that the stochastic FMSY estimated in EqSim for example, is lower than the deterministic FMSY and that the current guidelines ensure that the FMSY should not pose a more than 5% risk to Blim. A large amount of work described in WD 1 was carried out to develop an MSE framework to consistency and robustness test a candidate refer- ence point system for North East Atlantic stocks. However, WKREF2 recommended that further work needs to be carried out to condition and test the simulation framework before the conclu- sions could be adopted by ICES and incorporated into the guidelines. A number of considerations for defining MSY related reference points were discussed including using model validation and prediction skill to ensure that ICES provide robust and credible ad- vice. There is evidence that density dependence (DD) is important in the majority of ICES stocks (68% in recruitment and 54% in growth). The correct prediction of the shape and strength of density-dependence in productivity is key to predicting future stock development and providing the best possible long-term fisheries management advice. A suggested approach to use surplus production models (SPMs) to account for DD in FMSY was suggested and discussed but there was no consensus on whether that approach was appropriate. There was consensus that the FECO approach as a means of adapting target fishing mortality to medium-term changes in productiv- ity should be included in the guidelines subject to a benchmark and ACOM approval. While WKREF1 and 2 focused mainly on Category 1 stocks ToR c) called for a “simplified and harmonised set of guidelines for estimating MSY and precautionary reference points applicable in the advice framework across various ICES stock categories.” Ideally the ICES assessment cat- egories should provide equivalent risk across all stocks. This issue was discussed but no recom- mendations emerged. There was no consensus a revised reference point framework was proposed at WKREF2. How- ever, it was agreed that it should be presented here for further discussion at ACOM and other fora. The key feature of the suggested approach is that the stock status evaluation is treated in- dependent of the Advice Rule (AR). The main feature of the system is that the biomass trigger is not linked to a stock status evaluation, it is linked to the expected biomass when fishing at the target fishing mortality, in contrast to the current ICES approach. It also entailed that FMSY would also become an upper limit of fishing mortality and that the advised fishing mortality would be set at or lower than that level. WKREF2 did not discuss what to do in situations where SSB〈 Blim or alternative forms of HCR for the advice rule. Building community understanding and con- sensus around simplified and harmonised guidelines has yet to be achieved. A further workshop WKREF3 will be required to achieve that aim. The report includes 6 recommendations for ACOM consideration.
    Beschreibung: ICES
    Beschreibung: The main objective of the workshop was to review the recommendations of WKREF1 and con- sider how these might feed into a new reference points framework and guidelines for ICES. There were a number of presentations on the wider issues of best practice for reference points, the Allee effect, density dependence and the WKIRISH approach. The starting point was to try and develop a set of simplified and harmonised guidelines based on the WKREF1 report rather than evolving the current guidelines to include the WKREF1 conclusions. A key aspect of the meeting was to allow for discussions in order to build a shared understanding of the strengths and weakness of the current framework and of the new framework emerging from WKREF1.
    Beschreibung: Published
    Beschreibung: Non Refereed
    Schlagwort(e): ICES ; Reference points ; Management advice ; Fisheries ; Fishery management reference points
    Repository-Name: AquaDocs
    Materialart: Report
    Format: 103pp
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  • 4
    Publikationsdatum: 2022-10-26
    Beschreibung: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Dowd, S., Chapman, M., Koehn, L., & Hoagland, P. The economic tradeoffs and ecological impacts associated with a potential mesopelagic fishery in the California Current. Ecological Applications, 32(4), (2022): e2578, https://doi.org/10.1002/eap.2578.
    Beschreibung: The ocean's mesopelagic zone (200–1000 m) remains one of the most understudied parts of the ocean despite knowledge that mesopelagic fishes are highly abundant. Apex predators from the surface waters are known to consume these fishes, constituting an important ecological interaction. Some countries have begun exploring the potential harvest of mesopelagic fishes to supply fishmeal and fish oil markets due to the high fish abundance in the mesopelagic zone compared with overfished surface waters. This study explored the economic and ecological implications of a moratorium on the harvest of mesopelagic fishes such as lanternfish off the US West Coast, one of the few areas where such resources are managed. We adapted a bioeconomic decision model to examine the tradeoffs between the values gained from a hypothetical mesopelagic fishery with the potential values lost from declines in predators of mesopelagic fishes facing a reduced prey resource. The economic rationale for a moratorium on harvesting mesopelagics was sensitive both to ecological relationships and the scale of the nonmarket values attributed to noncommercial predators. Using a California Current-based ecological simulation model, we found that most modeled predators of mesopelagic fishes increased in biomass even under high mesopelagic harvest rates, but the changes (either increases or decreases) were small, with relatively few predators responding with more than a 10% change in their biomass. While the ecological simulations implied that a commercial mesopelagic fishery might not have large biomass impacts for many species in the California Current system, there is still a need to further explore the various roles of the mesopelagic zone in the ocean.
    Beschreibung: Sally Dowd acknowledges sponsorship from the WHOI Summer Student Fellowship and the Rausser College of Natural Resources Honors Program at UC Berkeley. This project would not have been possible without the guidance provided by Kama Thieler and Carl Boettiger. Porter Hoagland acknowledges funding from the Audacious Project, a collaborative endeavor, housed at TED and the J. Seward Johnson Fund in support of the Marine Policy Center at WHOI.
    Schlagwort(e): Bioeconomic model ; Fisheries ; Mesopelagic fishes ; Moratorium ; Nonmarket value ; Predators ; Rpath ; Willingness-to-pay values
    Repository-Name: Woods Hole Open Access Server
    Materialart: Article
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  • 5
    Publikationsdatum: 2022-10-26
    Beschreibung: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kourantidou, M., Hoagland, P., Dale, A., & Bailey, M. Equitable allocations in northern fisheries: bridging the divide for Labrador Inuit. Frontiers in Marine Science, 8, (2021): 590213, https://doi.org/10.3389/fmars.2021.590213.
    Beschreibung: Canada has undertaken commitments to recognize the rights of Indigenous Peoples in fisheries through policies and agreements, including Integrated Fishery Management Plans, the Reconciliation Strategy, and Land Claim Agreements (LCAs). In addition to recognizing rights, these commitments were intended to respect geographic adjacency principles, to enhance the economic viability of Indigenous communities, and to be reflective of community dependence on marine resources. We examined the determinants of quota allocations in commercial fisheries involving Nunatsiavut, Northern Labrador, the first self-governing region for the Inuit peoples in Canada. It has been argued that current fishery allocations for Nunatsiavut Inuit have not satisfied federal commitments to recognize Indigenous rights. Indicators that measure equity in commercial allocations for the turbot or Greenland halibut (Reinhardtius hippoglossoides) and northern shrimp (Pandalus borealis) fisheries were identified and assessed. In these two cases, historical allocations continue to predominate for allocations based upon equity or other social or economic considerations. We illustrate equity-enhancing changes in the quota distribution under scenarios of different levels of inequality aversion, and we make qualitative assessments of the effects of these allocations to Nunatsiavut for socioeconomic welfare. This approach could benefit fisheries governance in Northern Labrador, where federal commitments to equity objectives continue to be endorsed but have not yet been integrated fully into quota allocations.
    Beschreibung: This research was undertaken with funding from the Canada First Research Excellence Fund through the Ocean Frontier Institute (MK and MB) and the Johnson Endowment of the Woods Hole Oceanographic Institution’s (WHOI) Marine Policy Center (PH).
    Schlagwort(e): Fisheries ; Allocations ; Equity ; Indigenous rights ; Access
    Repository-Name: Woods Hole Open Access Server
    Materialart: Article
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  • 6
    Publikationsdatum: 2022-05-27
    Beschreibung: Buesseler, K., Jin, D., Kourantidou, M., Levin, D., Ramakrishna, K., Renaud, P., Ausubel, J., Baltes, K., Gjerde, K., Holland, M., Kostel, K., LaCapra, V., Martin, A., Sosik, H., Thorrold, S., Tierney, T., Joyce, K., Renier, N., Taylor, E. (2022). The Ocean Twilight Zone’s Role in Climate Change. Woods Hole Oceanographic Institution, 32 pp.
    Beschreibung: The ocean twilight zone (more formally known as the mesopelagic zone) plays a fundamental role in global climate. It is the mid-ocean region roughly 100 to 1000 meters below the surface, encompassing a half-mile deep belt of water that spans more than two-thirds of our planet. The top of the ocean twilight zone only receives 1% of incident sunlight and the bottom level is void of sunlight. Life in the ocean twilight zone helps to transport billions of metric tons (gigatonnes) of carbon annually from the upper ocean into the deep sea, due in part to processes known as the biological carbon pump. Once carbon moves below roughly 1000 meters depth in the ocean, it can remain out of the atmosphere for centuries to millennia. Without the benefits of the biological carbon pump, the atmospheric CO 2 concentration would increase by approximately 200 ppm 1 which would significantly amplify the negative effects of climate change that the world is currently trying to curtail and reverse. Unfortunately, existing scientific knowledge about this vast zone of the ocean, such as how chemical elements flow through its living systems and the physical environment, is extremely limited, jeopardizing the efforts to improve climate predictions and to inform fisheries management and ocean policy development.
    Beschreibung: Funding is: The Audacious Project housed at TED
    Schlagwort(e): Climate ; Mesopelagic ; Twilight Zone ; Fisheries ; Carbon Dioxide Removal ; Ocean ; Biological Carbon Pump ; Solubility Pump ; Carbon ; Marine Snow
    Repository-Name: Woods Hole Open Access Server
    Materialart: Other
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  • 7
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    In:  aqdchief@seafdec.org.ph | http://aquaticcommons.org/id/eprint/18569 | 2002 | 2015-11-15 16:06:30 | 18569 | Southeast Asian Fisheries Development Center, Aquaculture Department
    Publikationsdatum: 2022-08-02
    Beschreibung: This paper summarizes the results of the experiments on the induced breeding and larval rearing of milkfish (Chanos chanos) during the 1979 season. Milkfish larvae could be reared successfully without the use of trochophore larvae of oysters as feed during the first few days. In order to induce the ovulation of wild adult milkfish a higher dose of human chorionic gonadotropin hormone is required.
    Schlagwort(e): Fisheries ; Chanos chanos ; ISEW ; Philippines ; marine environment ; Brood stocks ; Fish culture ; Fish larvae ; Food organisms ; Induced breeding ; Larval development ; Sex hormones
    Repository-Name: AquaDocs
    Materialart: article
    Format: application/pdf
    Format: application/pdf
    Format: 1-3
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  • 8
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    In:  library@seafdec.org.ph | http://aquaticcommons.org/id/eprint/20100 | 17342 | 2016-02-24 22:18:26 | 20100 | Southeast Asian Fisheries Development Center, Aquaculture Department
    Publikationsdatum: 2022-08-02
    Beschreibung: An outline is given of aquaculture and fisheries in Asia, providing information of use to students whose work can influence laws, rules, policy and regulations on aquaculture and fisheries, with the view in mind to sustainable aquaculture. In this issue, the following countries are examined: China, Indonesia, and Bangladesh.
    Schlagwort(e): Aquaculture ; Fisheries ; Fishery management ; Aquaculture development ; Aquaculture regulations ; Marine aquaculture ; Freshwater aquaculture ; Fishery industry ; Asia ; Bangladesh ; China
    Repository-Name: AquaDocs
    Materialart: article
    Format: application/pdf
    Format: application/pdf
    Format: 7-8
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  • 9
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    In:  library@seafdec.org.ph | http://aquaticcommons.org/id/eprint/20067 | 2002 | 2016-03-04 15:16:24 | 20067 | Southeast Asian Fisheries Development Center, Aquaculture Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Fisheries ; Aquaculture ; Vietnam ; Sri Lanka ; Sri Lanka ; Vietnam ; brackishwater environment ; freshwater environment ; marine environment ; Aquaculture ; Aquaculture techniques ; Brackishwater aquaculture ; Feed ; Fish culture ; Fish diseases ; Fisheries ; Fishery data ; Food organisms ; Freshwater aquaculture ; Marine aquaculture ; Marine fisheries ; Mollusc culture ; Pond culture ; Seaweed culture ; Shrimp culture
    Repository-Name: AquaDocs
    Materialart: article
    Format: application/pdf
    Format: application/pdf
    Format: pp.9-10, 27
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  • 10
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    In:  library@seafdec.org.ph | http://aquaticcommons.org/id/eprint/20055 | 2002 | 2016-03-03 11:33:32 | 20055 | Southeast Asian Fisheries Development Center, Aquaculture Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Fisheries ; Aquaculture ; Asia ; Cambodia ; India ; Asia ; Cambodia ; India ; Myanmar ; Myanmar ; brackishwater environment ; freshwater environment ; marine environment ; Aquaculture ; Aquaculture development ; Aquaculture economics ; Aquaculture techniques ; Brackishwater aquaculture ; Catching methods ; Culture effects ; Environmental impact ; Fish culture ; Fisheries ; Fishery development ; Fishery resources ; Fishery statistics ; Freshwater aquaculture ; Marine aquaculture ; Shrimp culture ; Sustainability ; Trade
    Repository-Name: AquaDocs
    Materialart: article
    Format: application/pdf
    Format: application/pdf
    Format: pp.9-10, 29
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  • 11
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    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26291 | 23782 | 2019-04-08 09:42:05 | 26291 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Fisheries ; Pollution ; Indonesia ; Heavy metals ; Chemical pollution ; Pollution monitoring
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 10-19
    Format: 10
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  • 12
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    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26293 | 23782 | 2019-03-22 03:49:21 | 26293 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Fisheries ; Myanmar ; Heavy metals ; Cadmium ; Lead ; Mercury ; Biological sampling ; Fish ; Fishery products ; Seafood
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 38-46
    Format: 9
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  • 13
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    Secretariat, Southeast Asian Fisheries Development Center | Bangkok, Thailand
    In:  http://aquaticcommons.org/id/eprint/26259 | 2002 | 2019-03-01 05:56:06 | 26259 | Southeast Asian Fisheries Development Center, Secretariat
    Publikationsdatum: 2022-08-02
    Beschreibung: Round scad exploration by purse seine in the waters of western Philippines was conducted from April 22 to May 7, 1998 for a period of five (5) fishing days with a total catch of 7.3 tons and an average of 1.5 tons per setting. Dominant species caught were Decapterus spp. having 70.09% of the total catch, followed by Selar spp. at 12.66% and Rastrelliger spp. 10.70%. Among the Decapterus spp. caught, D. macrosoma attained the highest total catch composition by species having 68.81% followed by D. kurroides and D.russelli with 0.31% and 1.14% respectively. The round scad fishery stock was composed mainly of juvenile fish (less than 13 cm) and Age group II (13 cm to 14 cm). Few large round scad at Age group IV and V (20 cm to 28 cm) stayed at the fishery. Other fishes caught were: Auxis rochei (0.85%), A. thazard (0.12%), Caranx spp. (0.45%), Emmilichthys nitidus (0.58%), Euthynnus affinis (0.42%), Leiognathus ruconius (0.58%), Loligo sp. (0.31%), Megalaspis cordyla (0.09%), Rastrelliger spp. (10.70%), Sardinella longiceps (0.03%), Scomberoides lysan (0.24%), Selar spp. (12.66%), Sphyraena spp. (0.90%), Thunnus albacares (0.96%) and others (1.02%). Tuna and tuna like fishes such as yellowfin tuna, eastern little tuna, bullet tuna, frigate tuna and oceanic squid are distributed in the upper latitudes of the survey area. On the other hand, round scads, big-eyed scads and Indian mackerels are dominantly present in the lower latitudes of the survey area.
    Schlagwort(e): Fisheries ; Exploratory fishing ; Purse seining ; Age composition ; Catch composition ; Fishery surveys ; Carangid fisheries ; South China Sea ; Philippines ; Rastrelliger ; Decapterus
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 49-64
    Format: 16
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  • 14
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    Training Department, Southeast Asian Fisheries Development Center | Samut Prakarn, Thailand
    In:  http://aquaticcommons.org/id/eprint/26215 | 17342 | 2019-02-08 06:25:54 | 26215 | Southeast Asian Fisheries Development Center, Training Department
    Publikationsdatum: 2022-08-02
    Beschreibung: Presented in this paper is the status of the fishery industry in Brunei Darussalam. Specifically, it discussed the following topics: fishery management strategies, zonation scheme, licencing, the use of poisons and explosives, the minimum cod-end mesh size for trawlers, closed areas, enhancement of fishing grounds, and the enforcement activities.
    Schlagwort(e): Fisheries ; Fishery resources ; Fishery management ; Fisheries ; Ecological zonation ; Licensing ; Fish poisoning ; Catching methods ; Illegal fishing ; Explosive fishing ; Fishing gear ; Season regulations ; Fishing grounds
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 34-40
    Format: 7
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  • 15
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    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26295 | 23782 | 2019-03-22 08:39:12 | 26295 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Fisheries ; Thailand ; Cadmium ; Lead ; Mercury ; Biological sampling ; Fish ; Fishery products ; Seafood
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 53-58
    Format: 6
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  • 16
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    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26292 | 23782 | 2019-03-22 03:43:09 | 26292 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Fisheries ; Malaysia ; Cadmium ; Lead ; Mercury ; Biological sampling ; Fish ; Fishery products ; Seafood
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 20-37
    Format: 18
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  • 17
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    Secretariat, Southeast Asian Fisheries Development Center | Bangkok, Thailand
    In:  http://aquaticcommons.org/id/eprint/26258 | 2002 | 2019-03-01 06:00:19 | 26258 | Southeast Asian Fisheries Development Center, Secretariat
    Publikationsdatum: 2022-08-02
    Beschreibung: An exploratory tuna longline fishing survey was conducted using the research and training vessels of the Southeast Asian Fisheries Development Center, the 1,178 GT MV SEAFDEC and the Bureau of Fisheries and Aquatic Resources, the 165 GT MV MAYA-MAYA in the South China Sea Waters, West of the Philippines from April to May, 1998. A total of 3,796 hooks was set in sixteen (16) fishing stations. There were no tuna caught during the entire survey but only minor and irrelevant species like the Pacific lancetfish, sharks and an opah species, Lampris guttatus. The important fishing and oceanographic factors during the survey and other research results on longline are described and analyzed. Additional longline studies within and near the Philippines territorial waters are also presented to substantiate the research results of the joint SEAFDEC/BFAR resource exploratory.
    Schlagwort(e): Fisheries ; Exploratory fishing ; Catch composition ; Fishery surveys ; Longlining ; Tuna fisheries ; South China Sea ; Philippines
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 39-48
    Format: 10
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  • 18
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    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26299 | 23782 | 2019-03-27 06:00:01 | 26299 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Chemistry ; Fisheries ; Malaysia ; Pesticides ; Biological sampling ; Fish ; Fishery products ; Biochemical analysis ; Lethal limits
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 71-74
    Format: 4
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  • 19
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26300 | 23782 | 2019-03-27 05:58:36 | 26300 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Aquaculture ; Chemistry ; Fisheries ; Myanmar ; Pesticides ; Biological sampling ; Fish ; Fishery products ; Lethal limits
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 75-83
    Format: 9
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  • 20
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26307 | 23782 | 2019-03-27 03:35:56 | 26307 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Fisheries ; Indonesia ; Histamines ; Biological sampling ; Fish ; Fishery products ; Quality control
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 116-123
    Format: 8
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  • 21
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26303 | 23782 | 2019-03-27 05:51:15 | 26303 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Chemistry ; Fisheries ; Thailand ; Pesticides ; Biological sampling ; Fish ; Fishery products ; Dried products ; Lethal limits
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 100-105
    Format: 6
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  • 22
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26309 | 23782 | 2019-03-27 03:49:31 | 26309 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Schlagwort(e): Fisheries ; Myanmar ; Histamines ; Biological sampling ; Biochemical analysis ; Fish ; Fishery products
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 129-133
    Format: 5
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  • 23
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26826 | 23782 | 2019-11-21 00:56:12 | 26826 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: Presented in the paper is the standard procedure in the determination of K value which is an index to measure the enzymatic freshness of fish and squid. Specifically, reagents, apparatus and the analytical procedures needed and the calculations are presented.
    Schlagwort(e): Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Fishery products ; Fish inspection ; Fishery industry ; Food technology ; Standards ; Specifications
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: B-6.1-B-6.7
    Format: 7
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  • 24
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    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26825 | 23782 | 2019-11-21 00:52:35 | 26825 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: Presented in the paper is the standard procedure in measuring K value in fish meat by means of the freshness testing paper technique.
    Schlagwort(e): Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Fishery products ; Fish inspection ; Fishery industry ; Food technology ; Standards ; Specifications
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: B-7.1-B-7.2
    Format: 2
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  • 25
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26802 | 23782 | 2019-11-12 05:28:20 | 26802 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: Presented in the paper is the standard procedure in the measurement of pH in the fresh fish meat. Specifically, the procedures in sampling and sample preparation, apparatus and reagents required, and the analytical procedures are presented.
    Schlagwort(e): Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Microbiological analysis ; Fishery products ; Processed fishery products ; Fish inspection ; Fishery industry ; Food additives ; Food technology ; Standards ; Specifications ; pH
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: A-3.1-A-3.2
    Format: 2
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  • 26
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26842 | 23782 | 2019-11-15 07:54:48 | 26842 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: Starch is commonly used in the production of fish jelly products as an extender and as binding agent. The paper provides the methodology in the determination of starch in fish jelly products. Instructions for sample preparation and the reagents needed are presented. Detailed procedures in the determination of the starch in a sample are provided.
    Schlagwort(e): Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Fishery products ; Fishery industry ; Food technology ; Standards ; Specifications ; Starch ; Additives ; Food additives
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: D-4.1-D-4.4
    Format: 4
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  • 27
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26881 | 23782 | 2019-11-05 02:46:02 | 26881 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: Monitoring and investigative work undertaken in the Philippines regarding dinoflagellate blooms are described. Chronological observations of the occurrence of red tides, aerial surveys, spatial distribution of the dinoflagellate and the physical environment are discussed. Fishing and the examination of gut content of fish and mussels and bioassay tests are detailed. Incidents of paralytic shellfish poisoning in the Philippines are considered briefly.
    Schlagwort(e): Fisheries ; Health ; Environmental monitoring ; Red tides ; Public health ; Medicine ; Dangerous organisms ; Philippines
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 52-79
    Format: 28
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  • 28
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26885 | 23782 | 2019-11-05 02:23:34 | 26885 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: A report is made of the first incidence occurring of paralytic shellfish poisoning in Thailand in May 1983, following an extensive bloom of Trichodesmium erythraeum. Investigations undertaken regarding the source of the toxicity are outlined.
    Schlagwort(e): Fisheries ; Health ; Biological poisons ; Public health ; Red tides ; Shellfish ; Dangerous organisms ; Thailand
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 90-91
    Format: 2
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  • 29
    facet.materialart.
    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26879 | 23782 | 2019-11-05 02:54:38 | 26879 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: A brief account is given of recent cases of paralytic shellfish poisoning in Sabah, Malaysia, and toxicological studies undertaken. Hydrography surveys, underwater observations after the occurrence of the red tides and plankton studies and monitoring of red tides are discussed.
    Schlagwort(e): Fisheries ; Health ; Shellfish ; Toxicity tests ; Red tides ; Public health ; Dangerous organisms ; Malaysia
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 35-42
    Format: 8
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  • 30
    facet.materialart.
    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26852 | 23782 | 2019-11-15 07:36:44 | 26852 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: Cholera is an acute specific infection caused by the organism, Vibrio cholera. Diagnosis may be confirmed by the presence of large numbers of the comma-shaped bacilli on direct microscopic examination of a fecal or vomitus smear, and by the isolation of the organism on culture. Fish and shellfish have been identified as vehicles of cholera. Large numbers of V. cholera must usually be ingested to cause cholera. Thus problems often occur when poor handling and inadequate refrigeration have allowed the organism to multiply. Presented in the paper is the methodology of determining the presence of Vibrio cholera in fish and fishery products.
    Schlagwort(e): Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Fishery products ; Fishery industry ; Food technology ; Standards ; Specifications ; Aerobic bacteria ; Microbiological analysis ; Microorganisms ; Pathogenic bacteria ; Pathogens ; Health and safety ; Public health ; Microbial contamination ; Vibrio cholerae
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: E-7.1-E-7.5
    Format: 5
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  • 31
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    Secretariat, Southeast Asian Fisheries Development Center | Bangkok, Thailand
    In:  http://aquaticcommons.org/id/eprint/26890 | 23782 | 2019-11-14 01:01:29 | 26890 | Southeast Asian Fisheries Development Center, Secretariat
    Publikationsdatum: 2022-08-02
    Beschreibung: Fishery statistics in Brunei Darussalam have been collected by the Department of Fisheries since the 1940s. In the early 1980s, a number of statistics were collected, such as catch and effort data of artisanal fishermen, aquaculture statistics, processing statistics as well as data from major wet markets focusing on the amount, prices of marketed fish either from the local fishermen or imported. In 1984, the collection of statistics on commercial fishing was started. The statistics have been used in the formulation of fishery management and development policies as well as for sectoral development. Following a brief account of the responsibility and statistic collections of the Department of Fisheries, an examination is made of employment in the fishery sector, fisheries production, fish marketed and the GDP for the fishery industry. Fisheries in Brunei Darussalam is a very healthy industry, where production is well below the maximum allowable harvestable limit of 20,000 tons at 30%. The Department is embarking to increase production from the capture fishery to reduce the country's dependence on imported fish; the same applies for aquaculture, in order to complement production from the capture fisheries. The processing sector is also increasing in importance, especially with the increase in the number of capture fishery licenses, and the demand for quality and value-added products.
    Schlagwort(e): Fisheries ; Marine fisheries ; Fishery statistics ; Aquaculture development ; Aquaculture statistics ; Fish catch statistics ; Marine aquaculture ; Freshwater aquaculture ; Fishery development ; Marine ; Brackish ; Freshwater
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: 6-14
    Format: 9
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  • 32
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    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26843 | 23782 | 2019-11-15 07:52:55 | 26843 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: Sodium chloride is an important additive for the production of fish jelly products. It extracts the salt soluble protein to give the gel strength of the final product. The paper provides the methodology in the determination of the amount of sodium chloride in fish jelly products. Instructions for sample preparation and the reagents needed are presented. Detailed procedures in the determination of the salt in a sample are provided.
    Schlagwort(e): Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Chemical analysis ; Fishery products ; Fishery industry ; Food technology ; Standards ; Specifications ; Additives ; Food additives ; Salts ; Sodium chloride
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: D-5.1-D-5.2
    Format: 2
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  • 33
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    Unbekannt
    Marine Fisheries Research Department, Southeast Asian Fisheries Development Center | Singapore
    In:  http://aquaticcommons.org/id/eprint/26851 | 23782 | 2019-11-14 01:29:31 | 26851 | Southeast Asian Fisheries Development Center, Marine Fisheries Research Department
    Publikationsdatum: 2022-08-02
    Beschreibung: Food poisoning due to Vibrio parahaemolyticus is a food-borne infection resulting from the ingestion of a large number of this organism (about 106-109 viable cells). The major symptoms are diarrhea and abdominal pain with headache, fever, and vomiting also occurring. The organisms are excreted during the acute stage of the illness after which they decrease rapidly. The differentiation of V. parahaemolyticus from other pathogenic species of Vibrio is based mainly on salt tolerance, Voges-Proskauer reaction, fermentation of sucrose, and growth at 43°C. Presented in the paper is the methodology of determining the presence of Vibrio cholera in fish and fishery products.
    Schlagwort(e): Chemistry ; Fisheries ; Manuals ; Culture media ; Analysis ; Analytical techniques ; Methodology ; Fishery products ; Fishery industry ; Food technology ; Standards ; Specifications ; Aerobic bacteria ; Microbiological analysis ; Microorganisms ; Pathogenic bacteria ; Pathogens ; Health and safety ; Public health ; Microbial contamination ; Vibrio parahaemolyticus ; Vibrio cholerae
    Repository-Name: AquaDocs
    Materialart: book_section
    Format: application/pdf
    Format: application/pdf
    Format: E-8.1-E-8.6
    Format: 6
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  • 34
    Digitale Medien
    Digitale Medien
    Springer
    Environmental management 11 (1987), S. 479-493 
    ISSN: 1432-1009
    Schlagwort(e): Flushing ; Scouring ; Channel Maintenance ; Fisheries ; Trinity River
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Energietechnik
    Notizen: Abstract The operation of Trinity and Lewiston Dams on the Trinity River in northern California in the United States, combined with severe watershed erosion, has jeopardized the existence of prime salmonid fisheries. Extreme streamflow depletion and stream sedimentation below Lewiston have resulted in heavy accumulation of coarse sediment on riffle gravel and filling of streambed pools, causing the destruction of spawning, nursery, and overwintering habitat for prized chinook salmon (Salmo gairdnerii) and steelhead trout (Oncorhynchus tschawytscha). Proposals to restore and maintain the degraded habitat include controlled one-time remedial peak flows or annual maintenance peak flows designed to flush the spawning gravel and scour the banks, deltas, and pools. The criteria for effective channel restoration or maintenance by streambed flushing and scouring are examined here, as well as the mechanics involved. The liabilities of releasing mammoth scouring-flushing flows approximating the magnitude that preceded reservoir construction make this option unviable. The resulting damage to fish habitat established under the postproject streamflow regime, as well as damage to human settlements in the floodplain, would be unacceptable, as would the opportunity costs to hydroelectric and irrigation water users. The technical feasibility of annual maintenance flushing flows depends upon associated mechanical and structural measures, particularly instream maintenance dredging of deep pools and construction of a sediment control dam on a tributary where watershed erosion is extreme. The cost effectiveness of a sediment dam with a limited useful economic life, combined with perpetual maintenance dredging, is questionable.
    Materialart: Digitale Medien
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  • 35
    ISSN: 1573-5133
    Schlagwort(e): Chondrichthyes ; Elasmobranchs ; Fisheries ; Ageing methods ; Growth rates ; Gestation periods ; Maturity ; Vertebral bands ; Weight-length relationships ; Life histories
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Synopsis The silky shark, Carcharhinus falciformis, and scalloped hammerhead, Sphyrna lewini, represent 〉80% of the shark by-catch of the winter swordfish/tuna longline fishery of the northwestern Gulf of Mexico. This catch represents a potential supplemental fishery, yet little is known of the life histories of the two species. This report relates reproductive biology data to age and growth estimates for 135 C. falciformis and 78 S. lewini. Unlike other regional populations, C. falciformis in the Gulf of Mexico may have a seasonal 12 month gestation period. Males mature at 210–220 cm TL (6–7 yr); females at 〉225 cm TL (7–9 yr). Application of age at length data for combined sexes produced von Bertalanffy growth model parameter estimates of L∞ = 291 cm TL, K = 0.153, t0 = −2.2 yr. Adult male S. lewini outnumbered adult females in catches because of differences in the distributions of the sexually segregated population. Males mature at 180 cm TL (10 yr); females at 250 cm TL (15 yr). von Bertalanffy parameter estimates for combined sexes of this species were L∞ = 329 cm TL, K = 0.073, to = −2.2 yr.
    Materialart: Digitale Medien
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  • 36
    Digitale Medien
    Digitale Medien
    Springer
    Environmental biology of fishes 23 (1988), S. 141-154 
    ISSN: 1573-5133
    Schlagwort(e): Cyanide ; Diversity ; Development ; Ecology ; Environment ; Fisheries ; Pollution
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Synopsis The biological diversity and productivity of Philippine coral reefs are threatened by siltation, destructive fishing methods, coral and shell collecting and overfishing. Destructive fishing includes: the widespread, illegal use of explosives; poisons such as sodium cyanide; muro-ami and kayakas fishing; and trawling. The recent decline in catch rates threatens the livelihood of 700 000 near-shore subsistence fishermen who catch 55% of the total landings. The new government under Corazon Aquino wishes to protect the marine environment through the creation of a viable marine conservation management plan, enforcement of existing laws and through cooperation between government, non-government and international agencies to provide education and research. The Department of Agriculture, which has the authority for fisheries, has designated the International Marinelife Alliance as the lead non-government agency involved with fund raising, net-training and finding alternatives to destructive fishing methods.
    Materialart: Digitale Medien
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  • 37
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988) 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 38
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 413-420 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: This paper presents the development of the boundary element equations for the compression molding process of isothermal Newtonian fluids. It shows the numerical implementation of the boundary element equations and presents a simple method of carrying out the domain integral present in the governing equations. The results and accuracy of a boundary element simulation are discussed, and the numerical results compared to experimental values.
    Zusätzliches Material: 14 Ill.
    Materialart: Digitale Medien
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  • 39
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 605-609 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The static delamination behavior of graphite/epoxy composite specimens subjected to mode I tensile opening (using UDCBUniform double cantilever beam. specimens), and pure mode II shear loading (using ENFEnd-notched flexural. specimens) were studied. The graphite epoxy composites for the study were made from commercially treated fibers, with and without an electropolymerized interlayer. The mode I fracture energy (GIC) was found to be significantly higher (more than 50 percent) for the coated fibers. However, this improvement was accompanied by a high reduction (more than 3 times) in the mode II fracture energy (GIIC). This effect is apparently related to poor adhesion between the interlayer and the epoxy resin, which may be corrected by use of a “top layer” of appropriate composition to form chemical bonds between the phases. The fracture toughness (KIC) of composites made with commercially treated fibers was also evaluated, using double side-notched specimens.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
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  • 40
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 583-591 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: An analytical methodology was developed capable of describing interrelations between thermal processing and polymer structure for thermoplastic based composite laminates. Specifically, this modeling methodology was used to describe experimental results generated with a specially designed match die quench mold by processing both neat PEEK polymer and carbon fiber reinforced laminate samples at different cooling rates. The developed model accurately predicted temperature profiles for PEEK laminates of different thicknesses, under normal as well as extreme quenching conditions of 114°C/s. surface cooling rates that are possible to generate with the quench mold. In general, the modeling methodology is capable of predicting a part's thermal profile during processing in terms of the composite's microscopic intrinsic properties (fiber and matrix), composition, and lamina orientation. Furthermore, by coupling to the thermal profile description, a previously developed crystallization kinetics model for PEEK polymer and its carbon reinforced composite, a quantitative description of structural development during processing was obtained. Thus, with this analytical methodology, a skin-core crystallinity profile, where the crystallinity varies with part-thickness as a result of uneven cooling experienced during processing, was predicted both for the neat PEEK polymer and its carbon reinforced laminate forms. Finally, the developed methodology clearly established the interplay of both microscopic heat transfer and kinetics of crystallization/solidification of the matrix that must be accounted for in predicting the final structure of a carbon fiber reinforced laminate that will, in turn, govern microscopic and macroscopic performance.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 41
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 634-639 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Neat poly(ether-ether-ketone) (PEEK) and carbon fiber reinforced PEEK (APC-2) specimens were prepared using a variety of cooling rates to achieve a range of crystallinities. Amorphous specimens were exposed to a variety of fluids to determine the penetrant types which are able to strongly influence the material. This allowed the estimation of the solubility parameter and hydrogen bonding index for PEEK to be 9.5 and 3.1, respectively. Methylene chloride was used to investigate the kinetics of penetrant sorption. The data demonstrated Case II behavior, with the initial crystallinity having a pronounced effect on both the kinetic and equilibrium data. Accordingly, a model was proposed capable of describing the sorption level and penetration depth as a function of time given the sample crystallinity and sorption temperature. With Case II behavior there was no difference in the sorption kinetics of neat and fiber reinforced PEEK. Finally, the dynamic mechanical properties measured during sorption were found to be dependent on the sorption process.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
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  • 42
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 670-678 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The dynamic shear viscosity and the morphology of polypropylene homopolymer and copolymer blended with linear low density polyethylene are studied. A maximum in the dynamic shear viscosity vs. blend composition is reported for the polypropylene copolymer, linear low density polyethylene system. The increasing dynamic shear viscosity is in accordance with the occurrence of a morphology of polyethylene inclusions in rubber surrounded by a polypropylene matrix. Comparing calculations of the dynamic shear viscosities - based on a shell model with interlayer - and experimental results supports this view.
    Zusätzliches Material: 17 Ill.
    Materialart: Digitale Medien
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  • 43
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 684-687 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Hydroxy-terminated copoly(fstyrene-b-1,2-butadiene) (HPSB) containing rubber-affinitive vinyl side chains and having a molecular weight of 2000 to 4000 were prepared, and block copolyurethanes were synthesized by using a low molecular weight hydroxy-terminated poly (ethyl en e terephthalate) as a PET-affinitive component and 4,4′-diphenylmethane diisocyanate as a chain extender. The relationships between the molecular weight of HPSB, copolymerization ratio of styrene to butadiene and the adhesive strength of PKT/rubber in high temperature atmospheres were examined. A peak of adhesive strength was observed at styrene copolymerization ratio of 20 wt percent and a HPSB molecular weight of 3000. The adhesion mechanism was estimated from the behavior of the characteristic infrared absorption of block Copolyurethane in heating.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
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  • 44
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 718-727 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: In vibration welding of thermoplastics, frictional work done by vibrating two parts under pressure, along their common interface, is used to generate heat to effect a weld. The main process parameters in vibration welding are the weld frequency, the amplitude of the vibratory motion, the weld pressure, and the weld time. How these parameters affect weld quality, the conditions that result in the best welds, the weldability of dissimilar plastics, and the effect of fillers such as glass are of interest. To address these issues, a research vibration welding machine in which all the parameters can be independently and accurately controlled and monitored was designed and fabricated. The phenomenology of welding, as determined by experiments on the four thermoplastics polycarbonate, poly (butylene terephthalate), polyetherimide, and modified poly (phenylene oxide), is described.
    Zusätzliches Material: 19 Ill.
    Materialart: Digitale Medien
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  • 45
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 743-757 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: An engineering analysis of the reactive extrusion process of a thermoplastic polyurethane was made through numerical simulation and actual experiment. The reactants used in this system were 4,4′diphenylmethane diisocyanate, polycaprolactone diol (M.W., 824), and 1,4-bu-tanediol with equivalent weight ratio of 2:1:1. As a catalyst, dibutyltin dilaurate was used. The reaction kinetics and the viscosity function were obtained through experiments, and the mathematical model which includes the conservation equations of mass, momentum, energy, and chemical species was solved numerically to obtain the velocity, concentration, temperature, viscosity, and pressure profiles. The actual experiments were performed in the laboratory scale extruder to compare the experimental results with those of the numerical simulation.
    Zusätzliches Material: 30 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 46
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 775-784 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: A series of polyurethane-urea/polyvinyl simultaneous interpenetrating polymer networks (SINs) were prepared starting from a mixture of isocyanate prepolymer blocked with N-(1-1′-dimethyl-3-cxobutyl) acrylamide oxime, chain extender, vinyl monomers, and catalysts. Their physical properties and morphology were investigated using differential scanning calorimetry, dynamic mechanical measurements, and small-angle X-ray scattering. The polyurethane-urea networks examined were two-phase in nature. The vinyl network was formed with diacetone acrylamide oxime, trimethylolpropane trimethacrylate, and N-vinyl-pyrrolidone. Calorimetric analyses revealed that the polyether soft segment phase separated within the SINs. At higher temperature, dynamic mechanical measurements demonstrated the presence of only one glass transition temperature (Tg) intermediate in temperature to the Tg of the vinyl network and the Tg of the urethane hard phase. This is indicative of chain entanglement (interpenetration) between the vinyl network and the polyurethane hard segments resulting in a two-phase morphology. Small-angle X-ray scattering analyses provided measurements of diffuse phase boundary thickness, phase mixing, and domain size distribution. Appreciable interfacial thickness was not observed and thus phase mixing occurred within the phases. Domain size distribution indicated that high network constraints hindered the development of domains and limited the phase segregation.
    Zusätzliches Material: 10 Ill.
    Materialart: Digitale Medien
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  • 47
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988) 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 48
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987), S. 1021-1034 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Equations are derived that relate the orientation of “pseudo-affine” reoriented structural units after a biaxial deformation to the degrees and the directions of the effective drawings. The connection between these drawing parameters and those externally applied is analyzed in detail. It is shown how a comparison of these two sets of drawing parameters allows conclusions regarding the distribution throughout the material of the stresses that cause the deformation, the inhomogeneity of the deformation, and the role of non-orienting flow during deformation. In particular, the orientation of biaxially drawn poly(ethylene terephthalate) films is investigated, and it is shown what general information can be obtained on the deformation behavior of this material on the basis of these considerations.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 49
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987), S. 1059-1068 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Scale-up from small laboratory size extruders to large production size extruders is a procedure of great practical importance. Many scale-up rules and theories have been proposed in the past, however it is not always clear how the different scale-up methods will affect extruder performance. A basic analysis of scale-up in plasticating single screw extruders is developed from which the effect of a certain scale-up strategy on extrusion performance can be evaluated in terms of solids conveying, melting, melt conveying, mixing, residence time, heat transfer, power consumption, and specific energy consumption. Various existing scale-up theories are evaluated and compared using the basic analysis. A number of existing scale-up theories have some significant drawbacks, in particular with non-constant specific energy consumption and imbalance between melting rate and pumping rate. Conditions that are desirable to achieve in scale-up are enumerated and ranked in terms of importance. This leads to two new scale-up methods that result in constant mechanical specific energy consumption and high throughput rates. The first scale-up method keeps the specific surface area constant. This scale-up should work well for high values of the Brinkman number. However, at low values of the Brinkman number, the melting rate may be insufficient. The second scale-up method keeps the melting rate at low Brinkman number equal to the pumping rate and, thus, should be useful in cases where the first scale-up method cannot be used.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
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  • 50
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987) 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 51
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987), S. 1128-1136 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The plane strain fracture toughness and fracture mechanisms of several tough engineering plastics have been studied and compared with poly(methyl methacrylate) (PMMA), a relatively brittle polymer. The tough polymers all are observed to form a multiple craze zone at the crack tip, which is shown to be the primary source of plane strain fracture toughness in these materials. The multiple craze zone is retained during slow crack growth but is metastable, and at a critical stress intensity and associated crack velocity, the system passes through a transition to a greatly accelerated single craze mode of unstable propagation.
    Zusätzliches Material: 14 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 52
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987), S. 1148-1155 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The optical properties of bisphenol-A polycarbonate resin as described by the complex index of refraction, N = n - ik, are derived by Kramers-Kronig analysis of experimental absorption and reflectance data obtained in the range 40μm ≥ λ ≥ 105 nm. Electronic absorption processes in polycarbonate are characterized by two broad absorption peaks centered at ∼200 and ∼100 nm.
    Zusätzliches Material: 10 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 53
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987), S. 1182-1186 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Three-layer coextruded blown (either blend or composite) films, made of low-density polyethylene and linear lowdensity polyethylene (1:1 ratio) of identical density, were compared. The tensile properties of both systems are nearly as high as those of the linear polyethylene while high strain rate properties including impact strength and tear resistance of the composite film are superior. Some structural insight was obtained by thermal analysis and thermoelastic measurements. Structure property relationships are discussed in light of the unique behavior, structure, and morphology of linear low-density polyethylene. The two polyethylenes are only compatible to a rather limited extent mainly affecting their blend behavior. However, a strong mutual reinforcement effect was observed.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
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  • 54
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987), S. 1203-1208 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: A Viton copolymer containing vinylidene fluoride (VF2) and hexafluoropropylene (HFP), and a terpolymer containing VF2, HFP, and tetrafluoroethylene (TFE) were cross linked using varying amounts of Bisphenol AF to yield two series of fluoroelastomer networks, Stress-strain isotherms in elongation were determined for these samples at several temperatures and at two degrees of swelling with phenyl acetate. Strain-induced crystallization was observed, as evidenced by upturns in the isotherms at high elongations. It appears to be more pronounced in the terpolymer samples, presumably because the TFE units not only can crystallize themselves, but can co-crystallize with the VF2 units. The crystallization was found to persist upon moderate increase in temperature, but was suppressed when the networks were swollen, Thermoelastic (force-temperature) measurements were used to obtain values of the fraction fe/f of the elastic force that is due to energetic effects. Negative values were obtained for both types of samples and, in the case of two samples studied in detail, their magnitudes increased with increase in elongation. The magnitudes were larger and the increases more pronounced in the case of the terpolymer networks, as would be expected from a greater tendency for straininduced crystallization.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 55
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987), S. 1221-1228 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The transesterification reaction of molten ethylene and vinyl alcohol copolymers (EVA), in presence of paraffinic alcohols and basic catalysts, leads to high conversion of the ester groups to secondary alcohol in both discontinuous and continuous processing equipment. Various kinds of alcohols and two different catalysts were used. Sodium methoxide is a powerful catalyst for the equilibrated transesterification reaction, but we also observed side reactions, such as cross-linking with low-molecular-weight alcohols and hydrolysis of the catalyst followed by partial saponification of the EVA. Kinetic studies were performed in the presence of dibutyltin dilaurate, an efficient catalyst without any side reactions. The solubility of the main alcohol reagents was verified by diffusion measurements. The general reaction scheme and the related kinetics, corresponding to a homogeneous system, lead to a fair evaluation of the rate constants.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
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  • 56
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 27 (1987), S. 1252-1257 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The mechanical properties of polyurethane-unsaturated polyester interpenetrating polymer networks (IPNs) that were prepared by reaction injection molding (RIM) process were measured with variations In composition, cross-link density, and relative reaction rate. From dynamic mechanical analysis (DMA), it was found that the two component polymers had a good compatibility over the whole composition range. The tensile strengths of the blends were greater than those of the pure components and had a maximum value at 50/50 composition. The modulus of elasticity and surface hardness decreased and the impact strength increased as the polyurethane content was increased, but the changes were not high at low polyurethane content, below 50%. For higher cross-link density, the compatibility was enhanced and the mechanical properties were improved. When the reaction rates of the components were different, some extent of phase separation was found in DMA and the properties were affected adversely.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 57
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1152-1155 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Effects of absorbed moisture on degradation behavior of high nitrile barrier polymers were monitored using thermogravimetric analysis techniques. Non-modified and 10 percent rubber modified samples were heated isothermally at nitrile processing temperatures (200°C to 240°C) in air and nitrogen environments. Degradation was evaluated in terms of weight loss as a function of heating time and sample coloration. It was determined that complete removal of moisture, as well as high moisture concentration, contribute to increased degradation at the temperatures evaluated. Moisture levels in the range of 0.15 to 0.5 percent were found to minimize degradation. Heating environment, time, temperature, and rubber modification were also found to influence thermal stability.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
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  • 58
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1167-1172 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: High density polyethylene has been chlorinated by three different methods: in suspension and in solutions of two different solvents. Carbon-13 NMR and infrared analysis show that chlorination in chlorobenzene solution leads to statistically random distribution while chlorination in suspension gives highly blocky substitution. An intermediate distribution was obtained by chlorination in tetrachloroethane solution.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 59
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1198-1202 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The energy stored in polystyrene after plastic deformation is measured by the differential scanning calorimetry (DSC) technique. Similar to metals, the stored energy increases with plastic straining, first rapidly, and then more slowly, and finally the stored energy seems to approach a saturation value (about 1 cal/gram). By comparing to the plastic work done, the fraction stored ranges from 30 percent after 10 percent compression to 10 percent after 60 percent compression. The fraction is about twice as large as that of copper. The release of stored energy has two distinct parts, one below Tg and the other above Tg. Most of the strain recovery seems to accompany the second part. By using the Kissinger plot, the second part has an activation energy, of 142 kcal/mole which is about 10 percent larger than that of compressive strain recovery.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 60
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1219-1226 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: A trial and error approach reflects the state of the art in reaction injection molding. Material and process parameters determine the “moldability” of a specific system in a particular application. The concept of “molding areas” on the critical parameters plane can be extended form thermoplastic injection molding (TIM) to reaction injection molding (RIM).In this work moldability diagrams for the filling and curing stages of a RIM process are obtained based on a simplified engineering approach. The key process parameters chosen for the filling stage are initial material temperature and filling time. In the curing stage, the critical parameters are considered to be mold wall temperature and demold time. Experimental results obtained on a laboratory-scale RIM machine on a Crosslinking polyurethane system are used to check the validity of the predicted molding areas. The agreement obtained is satisfactory considering the broad range of processing parameters used.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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  • 61
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The microstructure of injection molded bars (2.9 and 5.8 mm thick) of thermotropic liquid crystalline poly(p-hydroxy-benzoic acid-co-ethylene terephthalate) has been studied by SEM on samples etched with n-propylamine, SEM fractography, DSC, IR, ESCA, WAXS and polarized microscopy. The 2.9 mm bar consists of three different layers: a highly oriented surface skin, an oriented intermediate layer and a non-oriented core. The 5.8 mm bar has a more complex microstructure and is composed of five different layers: a highly oriented surface skin, an oriented layer just beneath, a non-oriented layer, another oriented layer and a non-oriented core. The thicknesses of the different layers vary, significantly, with distance from the mold gate. The thickness of the core increases, significantly, with increasing distance from the mold gate at the expense of the oriented layers. The structure within the different morphological layers is not perfectly uniform. Tensile testing demonstrated the mechanical anisotropy of the surface material (a ratio of almost 20 between the longitudinal and transverse moduli) and the isotropy of the central core material.
    Zusätzliches Material: 15 Ill.
    Materialart: Digitale Medien
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  • 62
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1264-1269 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Rolling-drawing is a simple, effective, solid state processing technique for manufacturing high strength and high modulus oriented polymer sheet products. The process is capable of increasing the tensile modulus and strength of polypropylene by more, than an order of magnitude with inexpensive equipment and straight forward controllable techniques. This paper gives an overview of the rolling-drawing of polypropylene. It is intended to answer the following questions. What is rolling-drawing? What changes in tensile properties can be expected as a result of this process? What deformation processes occur during rolling-drawing? What are the processing variables and how do these variables relate to the deformation ratio achieved by rolling-drawing? A tensile flow stress relationship was formulated from experimental data for oriented polypropylene. This constitutive equation, estimates the flow stress (or yield stress) of the polymer as a function of deformation ratio, strain rate and temperature. Since stretching was found to provide a significant portion of the deformation during the rolling-drawing process a Hoffman-Sachs computer analysis was written to predict plastic deformation and drawing forces in the stretch zone. The results of experimentation and the analysis are briefly compared in this paper.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
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  • 63
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: An extrusion-grade of high density polyethylene (HOPE) (3 ethyl groups per 1000 carbons) has been divided into 16 fractions by preparative GPC and selective p-xylene extraction. The fractions, with molecular weights ranging from 900 to 1,000,000, have been studied by IR spectros-copy, DSC, WAXS, polarized microscopy, and small-angle light scattering (SALS), The average degree of chain branching (percent C2H5) is 0.5 percent for the part of the sample having a molecular weight lower than 10,000 and it decreases monotonically with increasing molecular weight, finally approaching 0.1 percent C2H5. A crystallinity depression with respect to linear PE equivalent to 20 percent/(percent C2H5) is recorded for all samples except for the very low molecular weight samples for which the crystallinity depression is much larger (30 to 35 percent/ (percent C2H5)). The unit cell volume increases with increasing percent C2H5, presumably due to the inclusion of ethyl groups in the crystals as interstitlals at 2gl kinks. The concentration of ethyl groups in the crystals (∊c) unanimously follows the relationship: ∊c(percent) = 0.32 + 0.25 log(percent C2H5) except for the low molecular weight fractions which have significantly lower values for ∊c. Our admittedly speculative explanation for this major discrepancy between high and low molecular weight samples is based on the idea that segments with ethyl groups close to chain ends have a greater difficulty in crystallizing than segments containing ethyl groups located at positions far from the chain ends. The fractions obtained from the extrusion-grade HDPE show a solidification temperature depression with respect to linear PE which can only be explained by the presence of chain branches in these samples. The depression is particularly pronounced for the low molecular weight samples as is expected from the data on molecular structure. Well-developed non-banded spherulites are observed in rapidly cooled (crystallized at about 35 K supercooling), low molecular weight samples (6,000 〈 Mw 〈 8,000)from the extrusion-grade HDPE in contrast to the axialites observed in linear PE of the same molecular weight and thermal treatment. This discrepancy in morphology has been related to the presence of ethyl groups in the extrusion grade HDPE fractions. Higher molecular weight samples (20,000 〈 Mw 〈 1,000,000)from the extrusion-grade HDPE and linear PE both display well-developed banded spherulites of similar nature as is expected due to the similarity in molecular structure of the two sets of sample.
    Zusätzliches Material: 18 Ill.
    Materialart: Digitale Medien
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  • 64
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1066-1070 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: In this work, a concept of distributed damage, including its inception and propagation, was applied to creep induced buckling of specimens prepared from high density polyethylene (HDPE). Using a kinetic relationship for damage accumulation, an integral equation for the front of the damage zone was derived. A time parameter associated with the inception of the damage front was obtained. The motion of the front was approximated for small times. Long time estimation was obtained using an assumption for a shape of the damage distribution. These results enabled us to review reported experimental results on creep induced buckling using a new insight into the relationship between applied load and time to buckle.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 65
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1095-1106 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: We present a basic study of the thermal, dielectric, Theological, and mechanical properties of hydroxybenzoic acid-ethylene terephthalate copolymers (PHB-PET). It is argued that they have two-phase structures, one rich in ethylene terephthalate (PET) and one rich in hydroxybenzoic acid (PHB). Polystyrene (PS) is immiscible in 60% PHB-PET (60-PHB-PET) blends. Polycarbonate (PC) is partially miscible with the high PET phase of 60-PHB-PET. PET seems completely miscible with this high PET phase. Shear viscosity measurements on blends indicate that 60-PHB-PET gives rise to large reductions of viscosity. Extrudates and melt-spun fibers have been prepared. The phase morphologies of low PHB-PET blends as determined by scanning electron microscopy indicate ellipsoids or long fibrils of the, 60-PHB-PET in PS or PC matrices. High extrusion rates and melt spinning produce fibrillar structures. The mechanical properties of films, extrudates, and melt-spun fibers were studied. Blends with 10% 60-PHB-PET exhibited significant increases in Young's modulus and tensile strength.
    Zusätzliches Material: 29 Ill.
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  • 66
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988) 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 67
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1145-1151 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The kinetics of the activated anionic polymerization of caprolactam to nylon-6 and its copolymers has been studied. Nylon-6 block copolymer and nylon-6 were prepared at various initial reaction temperatures (140°C to 165°C) by anionic polymerization in an adiabatic dewar flask. Different concentrations of poly(ethylene oxide) (PEO) in 4,4′-diphenyl methane diisocyanate (MDI)-capped PEO and 1 mole percent MDI, in a caprolactam solution, were used as the activators with the catalyst, the sodium salt of caprolactam. The kinetics of the reaction were analyzed from an adiabatic temperature rise. A new method was applied to determine the rate parameters. The activation energy, Ea, of nylon-6 and nylon-6 block copolymers were found to be 22 kcal/mole. The collision frequency factor, Ao, steadily decreased and the autocatalytic constant, Bo, decreased to a constant value of 16 with the introduction of PEO. However, it was found that the order of reaction, n, was almost a constant value at the second order for all experiments.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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  • 68
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1173-1181 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Chlorination of high density; polyethylene results in polymers which consist of unmodified methylene units and chlorinated methylene co-units. The effect of the concentration and distribution of chlorinated units on the solid state structure has been examined by thermal, wide angle X-ray diffraction and dynamic mechanical analysis. As the substitution becomes more random, the crystallinity, crystallite size, and crystalline perfection decrease for a given chlorine content. The chlorinated units are shown to be capable of co-crystallizing, and the concentration of chlorine in the crystalline phase increases as the distribution is made more random. Concurrently, the chlorine concentration of the amorphous phase decreases. Segregation of chlorine into the amorphous regions is most efficient when the substitution is blocky.
    Zusätzliches Material: 13 Ill.
    Materialart: Digitale Medien
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  • 69
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988) 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 70
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1240-1247 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The reversible step growth polymerization in homogeneous continuous flow stirred tank reactors (HCSTRs), in which the condensation product (W) leaves the reactor through flashing, has been analyzed. The molecular weight distribution (MWD) of the polymer formed is governed by nonlinear coupled algebraic relations to be solved simultaneously. To find the MWD numerically a large number of these are normally solved simultaneously using a suitable iterative procedure. In this paper, these have been decoupled using the technique proposed in our earlier works (1, 2) and the MWD can now be obtained sequentially without any trial and error. This leads to considerable saving in computation time compared to methods currently used. To demonstrate the efficacy of the algorithm, the polycondensation step of the poly(ethylene terephthal-ate) (PET) formed in HCSTRs has been analyzed. The MWD, the average chain length and the polydispersity index of the polymer have been computed and it takes 0.1 CPU seconds on a DEC 1090 as opposed to the earlier method which would take seventy minutes for similar computations. The simple model of the HCSTR for the PET formation gives the effect of reactor temperature and pressure and the quantitative results have been presented in this paper.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
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  • 71
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1270-1274 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: A mathematical model is presented which describes the degree of cure in a thermosetting adhesive used to bond sheet molding compound (SMC) components. The model allows computer aided optimization of the thermosetting process for any type of electromagnetic heating of the various layers of the structure (e.g. dielectric, microwave or induction), arbitrary material properties and arbitrary layer thickness. Computer simulated results are given for the particular case when the cure of the thermosetting material is initiated by its exposure to a high-power radio-frequency electric field (dielectric heating). These results indicate a strong sensitivity of the process to the thickness of the adhesive layer and the degree of coupling with the electromagnetic field. The analysis demonstrates that substantial heat losses from the relatively thin adhesive layer to the structural members of the joint by diffusive heat flow can be counterbalanced by additional electric power dissipated either in the adhesive or the structural members of the joint. Although derived for dielectric heating, those results are general, being independent of the type of electromagnetic heating employed.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
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  • 72
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1275-1275 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Linearly tapered coat hanger dies or T-dies are widely accepted. Nevertheless a newly proposed curvilinearly tapered coat hanger die has been shown to perform much better. It costs about the same as the other types of dies. This contribution is considered in terms of the recent literature.
    Materialart: Digitale Medien
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  • 73
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988) 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 74
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1304-1312 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: We have determined the degree of stiffness of a poly(γ-benzyl α, L-glutamate) (PBLG) chain in benzyl alcohol by measuring the intrinsic viscosities of dilute Solutions with differing molecular weights. Viscoelastic properties in oscillatory shear flow have been studied and the dependence of the loss and storage moduli on temperature, composition, and frequency are reported. We have also studied the transient shear stress relaxation behavior of the PBLG gel at different temperatures and concentrations. A comparison has been made between these gels and a classical poly(dimethyl siloxane) (PDMS) network, as well as, typical glassy polymers. Shear creep and recovery measurements have been made for this system. Some extensional step strain experiments using lubricated squeezing have been investigated. Tensile experiments have been made to determine stress-strain relationship during elongation. Preliminary experiments using the impulse approach to viscoelasticity further indicate the high elastic contribution in the gel.
    Zusätzliches Material: 13 Ill.
    Materialart: Digitale Medien
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  • 75
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1342-1342 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 76
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1347-1354 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: It is well known that equilibrium, thermodynamic properties are governed by different functional derivatives of the thermodynamic functions of state. For example, the phase behavior of mixtures of low and/or high molar mass components is determined by the compositional derivatives of the free energy. In this contribution, the merits of the Simha-Somcynsky theory in describing and predicting the phase behavior of mixtures are considered. The influence of temperature and composition on the miscibility behavior for practically binary polymer solutions are studied. Furthermore, the important aspect of polydispersity, inherent to synthetic polymer systems will be addressed.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
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  • 77
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989) 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 78
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 1-1 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 79
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 29-35 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: A recently developed analytical technique, modulus profiling, conveniently allows the mechanical properties of elastomers to be mapped with spatial resclutions approaching 0.05 mm. Thus, spatial heterogeneities in modulus caused by processing and aging phenomena can be easily monitored. This paper describes some typical results from polymer aging studies, which Indicate the insights available from this technique. These include application of modulus profiling to understanding (1) mechanical property deterioration of Viton in an elevated temperature, gamma-radiation environment, (2) recent continuous stress-relaxation results, and (3) the role of ozone for non mechanically-stressed materials in high energy radiation environments.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
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  • 80
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 55-62 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Thermal and mechanical studies on many linear polyesters have revealed their behavior in crystalline, liquid crystalline, and amorphous phases. Their phase behavior in binary compositions has also been studied by a range of additional techniques and in combinations including the polycarbonate of bisphenol-A. Regions of amorphous compatibility and incompatibility have been identified and measures made of transition temperature changes with composition. The conditions for transreaction have also been determined and the properties measured for the resultant new copolymers.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 81
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989) 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 82
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 100-106 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The present paper describes the evaluation of nonlinear thermally induced residual stresses in the cooling of polymer melt during injection molding of plastic components. The computational methodology adopted is based on the transfinite element approach, which is a hybrid scheme as it combines transform methods and classical Galerkin schemes with finite element formulations to preserve the modeling versatility. The applicability of the proposed formulations for understanding the physics and the nature of the nonlinear thermally induced stresses in the solidifying process of a sample amorphous polystyrene specimen demonstrates the basic capabilities and potential of the methodology. Results obtained agree qualitatively well with earlier research studies and experimental findings relevant to thermally induced residual stresses in the injection molding of plastic components.
    Zusätzliches Material: 13 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 83
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 127-133 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: A method to obtain microscopic and macroscopic coatings with improved resistance to debonding is described. The procedure, based on polymer-metal complexes, involved the adsorption on inorganic substrates of a poly(vinyl alcohol)-copper II chelate that is also able to catalyze the polymerization of monomers or prepolymers with grafting. The molecular structure of the complex, its adsorption on inorganic surfaces, and the mechanism of the polymerization induced by the supported catalyst are summarized. Much emphasis is placed on application of this technology to the realization of encapsulated filler and pigment and of coatings with improved adherence and solvent resistance. In the field of composite materials, it is demonstrated from several examples that the encapsulation of the filler can be a way to block chemical interactions between filler and matrix, to promote filler dispersion, and to improve mechanical properties.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 84
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1572-1577 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The effect of titanate, zirconate, and zircoaluminate coupling agents on the viscosity of zirconia-polypropylene injection molding blends was investigated. The zircoaluminate did not influence viscosity while the two former additives effected a considerable reduction. The titanate coupling agent also reduced the viscosity of the polymer in the absence of ceramic powder, and was more efficient in this respect, as a flow modifier than dioctyl phthalate. A comparable effect on the ceramic suspension was obtained by adding a species similar in molecular structure to the titanate coupling agent but without coupling ability.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 85
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 1581-1585 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The dielectric properties of thermoplastic and cross-linked polyethylene compounds with a low structure medium thermal carbon black are described in the frequency range between 30 and 8000 kHz as a function of frequency, temperature, and carbon black loading. Very high values of the dielectric constant were obtained for the conductive samples. The systems investigated are shown to follow percolative type models with experimental critical exponents in good agreement with the predicted values. The dielectric constant increases slowly with the carbon black concentration up to roughly the percolation concentration, then increases rapidly, and subsequently decreases at the higher black loadings. The dissipation factor-concentration curves show maximum values in the vicinity of the percolation concentration. The dielectric properties of these systems are discussed in terms of interfacial Maxwell-Wagner polarization effects.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 86
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 372-376 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: This paper presents a method for analyzing the cure of multilayer circuit boards containing chemically reactive adhesive interlayers. The cure kinetics of the adhesive are first quantified by differential scanning calorimetry, using the method of Freeman and Carroll to obtain the numerical kinetic parameters. These parameters are then used in a finite-element model of the circuit board which solves the heat and species transfer equations simultaneously. It is then possible to predict the temperature and extent of reaction at any time and position within the laminate, enabling the curing program to be optimized.
    Zusätzliches Material: 6 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 87
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 403-403 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 88
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 429-433 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: A method for estimating the polymer melt extrudate temperature fluctuation in the single screw extrusion process is proposed. Predictions of the melt temperature fluctuation is feasible if the extrusion process parameters are known. The method is superior to these in the literature because it incorporates effects of the melting process on the temperature fluctuation. The method has been verified experimentally.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 89
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 453-459 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: An investigation was undertaken to study the extrusion behavior of composite systems. A compound made up of approximately 50 percent ceramic particulates by volume dispersed in a high molecular weight thermoplastic polymer was characterized by measuring the shear viscosity on an Instron capillary viscometer. The experimental data indicated that the ceramic composite exhibited an apparent yield stress. As a result, an expression that was previously shown to provide flexibility for describing a yield stress at low rates of deformation could explain the viscosity of the ceramic composite. The expression was then applied to the flow analysis of both a “rod” and a “slit” die in an extrusion process, and the derived equations adequately correlated experimental volumetric flow rate us. Pressure drop data obtained on a laboratory extruder.
    Zusätzliches Material: 11 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 90
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 485-490 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: A model for the molding by reactive injection of reinforced plastics for systems in which fiber glass reinforcements are placed into the molds, is proposed. It allows for the determination of processing parameters and their influence on dependent variables: conversion, temperature, and pressure. Moldability areas, where premature gelling is avoided, are defined. Operating conditions are selected to reduce cycle time, produce small load losses, and provide a fairly uniform curing stage throughout the product.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 91
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 510-516 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: For linear copolymer molecules, the refractive index increment depends on the chemical composition of the molecules. However, the polydispersity in chemical composition of the sample introduces a great complexity in the data analysis in order to obtain a true molecular weight distribution. Even when the mean chemical composition does not depend on the molecular weight, a correction has to be applied when the output of an instrument depends quadratically on the refractive index Increment of the sample, such as in a light-scattering measurement. For that purpose, the light-scattering expressions are written in terms of polydispersity in chemical composition, which in turn is modeled using linear copolymerization equations. The microstructure effects, which are related to the order in which two different kinds of monomers appear along the chain, are not as yet taken into account in this approach.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 92
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 28 (1988), S. 506-509 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: In this work, creep induced buckling was studied for a number of thermoplastic materials. The effect was observed by monitoring top displacements of thermoplastic bars as a function of time under static loading conditions. The recorded times to failure were averaged and correlated with the applied loads. The experiments, conducted for different materials, established an exponential dependence between the critical time and the load. The evolution of the buckling eigenvalues was modeled numerically. The simulations of eccentric columns behavior under compressive loads were coupled with the eigenvalue analyses. The correlation of the time-load predictions obtained from the numerical simulations followed the experimental results within acceptable limits. The observed phenomenon of creep induced buckling was explained by damage accumulation leading to an effective reduction of the load carrying capability.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 93
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 334-338 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: As a result of increased interest from industry in using dielectric cure monitoring, a need has arisen for simplifying frequency, cure, and temperature dependent data so that control decisions can be readily made. Techniques utilizing data covering several decades of frequency now exist for separating ionic conduction levels from dipole and electrode polarization responses. Ionic conduction levels are particularly useful since they can be correlated to both viscosity and extent of cure. In addition to being a function of extent of cure, dielectric properties are also influenced by temperature. This dependence often makes the dielectric response more difficult to interpret. This paper investigates two methods for overcoming the temperature dependence of the dielectric response during nonisothermal cure. The first method utilizes recent WLF modeling techniques and extends them with the end result of extracting Tg in real time during cure. The second technique involves measuring the temperature dependence of uncured and cured material. Utilizing the correlation between log ionic conductivity and extent of cure, which has been noted by previous researchers, the normalized conductivity can be converted to a cure index. Several examples including epoxy, polyurethane, and a UV cured photoresist are presented, showing data before normalization and after both Tg and cure index determination.
    Zusätzliches Material: 11 Ill.
    Materialart: Digitale Medien
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  • 94
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 359-365 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Poly(ethylene terephthalate) (PET) and bisphenol-a-polycarbonate (PC) are known to form a miscible blend whereas ternary blends of PET, PC, and polypropylene (PP) form two phases. This is based on the considerations of various chemical events which may occur in these systems. The role of ester-carbonate interchange reactions during melt mixing and fabricating is found to be unimportant. Differential scanning calorimetric analysis of the ternary blends shows that there appears to occur an exothermic transition in the heating mode of the instrument. This exothermic event was found to be suppressed considerably by incorporating suitable additives into the system. Degradation reactions studied by thermogravimetric analysis and a dilute solution viscometric technique reveal that there exists some kind of interaction among the components even with the immiscible PP component.
    Zusätzliches Material: 9 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
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  • 95
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 397-404 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Interpenetrating polymer networks of polyurethane and unsaturated polyester were prepared by reaction injection molding (RIM) and transfer molding. The structures of the molded samples were analyzed by electron microscopy and dynamic mechanical analysis. It was found that polymer morphology and dynamic mechanical properties depend strongly on the molding temperature, reaction rate and reaction sequence. Simplified structure models based on Takayanagi's model and sample morphology can predict the storage modulus reasonably well but not the tanδ.
    Zusätzliches Material: 14 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 96
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 432-432 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 97
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 448-455 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The plasticating or melting behavior of polymer pellets sliding on a hot metal surface was investigated. An analytical model was developed for predicting the melting rate and the shear stress of an incompletely compacted solid bed of pellets in terms of the rheological and thermodynamic properties of the polymer, the pellet size, the degree of compaction, and the operating conditions. This investigation extends the results of the previous investigators obtained for a fully compacted solid bed of polymers to an incompletely compacted solid bed of polymers, closely representing the initial stage of the plasticating mechanism inside a screw extruder. Experimental verification of the analytical model developed here was made by testing six different commercial polymers.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 98
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 456-462 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Vitrification occurs during the reaction injection molding (RIM) of epoxy resin, and the curing reaction rate is reduced as the Tg of the reacting mixture exceeds or approaches the local reaction temperature inside the mold cavity. The effect will be manifested in the distribution of the glass transition temperature across the thickness direction of the molded product. The reaction kinetic equation which includes the vitrification term in the form of the WLF equation is used in the computer simulation of the epoxy RIM process and the effect of the vitrification is shown by comparing with models with no vitrification considerations.
    Zusätzliches Material: 8 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 99
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 479-487 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The performance of screws of advanced design in injection molding has been investigated with respect to four different objectives: (1) improvement of distributive mixing; (2) improvement of dispersive mixing; (3) increase of plasticating capacity; and (4) reduction of inhomogeneity of melt temperature.The screws used are three zone screws with different compression ratios, screws with pineapple or Maddock/Egan mixing elements, with one or two channel barrier sections, with static mixers mounted in the valve or in the nozzle, or with combinations of these different elements. The best mixing quality is obtained with multi-channel Maddock sections. The highest plasticating capacity and, consequently, the shortest cycle times are achieved with the barrier screws. Temperature measurements show that these screws improve melt homogeneity considerably with a relatively small loss of plasticating time. In all cases, increasing the back pressure gives inferior results compared with improvement of the screw design.
    Zusätzliches Material: 14 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 100
    Digitale Medien
    Digitale Medien
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 29 (1989), S. 505-512 
    ISSN: 0032-3888
    Schlagwort(e): Chemistry ; Chemical Engineering
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The impact fracture energy (Gc) for a polypropylene homopolymer and a copolymer with and without calcium carbonate fillers was measured over a range of temperatures between -40°C and 40°C using fracture mechanics principles. The fillers studied were Omyacarb (∼2.7 μm) and Winnofil (∼75 nm) and 10% by weight was added to the matrix material. These fillers did not have any appreciable effect on Gc of the copolymer-based composites. However, the Omyacarb fillers improved Gc of the homopolymer at low temperatures (≤20°C) due to enhanced microplastic flow as observed on the fracture surfaces. The fillers increased the stiffness of both the homopolymer and copolymer. It would appear that up to 10% of cheap calcium carbonate fillers could be added to the more expensive polypropylene to reduce the production cost without any significant loss of impact fracture energy.
    Zusätzliches Material: 15 Ill.
    Materialart: Digitale Medien
    Standort Signatur Erwartet Verfügbarkeit
    BibTip Andere fanden auch interessant ...
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