ALBERT

Description: A low specific speed pipeline pump is researched to improve work performance through several certain modifications. The target is to raise the pump's head up to 80m and increase its total efficiency to 26.5% when the volume flow rate is 6.3m3/h with a rotatory speed of 2960rpm. CFD Numerical simulation is employed to predict the hydraulic performance of the pump. The volute is redesigned and splitters are imported to change the structure of the impeller. A lot of factors are taken into account, for instance number of vanes, forms of vanes, width of the volute, shape of volute's cross section, etc. These transformations ameliorate the distribution of pressure and velocity in the impeller and volute that finally increase the pump's hydraulic efficiency. The impeller trim has also been made according to the affinity law to fatherly decrease the disc friction which causes pump's mechanical loss and then achieves the optimization goal finally. It is a practical case in low specific s...

Description: 〈span〉〈div〉ABSTRACT〈/div〉To ensure the accuracy of future seismological studies using horizontal‐component data recorded by broadband seismic stations in Africa and environs, we investigate the sensor orientation of 1075 stations belonging to 41 seismic networks deployed in and around the African continent in the past three decades. We applied three independent waveform‐based orientation estimation methods that involve the measurement of 〈span〉P〈/span〉‐wave particle motion based on the principal component analysis, minimizing the 〈span〉P〈/span〉‐wave energy on the transverse component of motion, and measuring intermediate‐period Rayleigh‐wave arrival angles from teleseismic earthquakes. We found that 34.3%–43.5% of the stations are well oriented within 3°, 40%–48.2% have sensor misorientation values between 3° and 10°, whereas 16.5%–18% of the stations are misaligned by more than 10°, most likely true sensor misorientation. The fairly high correlation coefficients (0.71–0.93) and very small mean (−0.01°–0.06°) and median (−0.04°–0.3°) differences suggest a high consistency among the estimates from the three methods. Likewise, the comparison of our results with reported orientations in the metadata at 33 stations demonstrates the robustness of the results obtained in this study. Likewise, the increase in the cross‐correlation coefficients and reduced time shifts between the Rayleigh‐wave signals on the vertical and Hilbert‐transformed radial components when the sensor misorientation angles are corrected show the importance of this study. An investigation of the time dependence of the estimated misorientation angles over the validation period reveals that the sensor orientation remained fairly constant for most stations included in the study. The nearly 180° sensor misorientation angles obtained at some stations led to the suspicion of possible polarity reversal of the seismometer components and/or channel mislabeling that was confirmed with a network manager for two of the seismic stations. Result of this study serves as a reference for future data users and a reminder to seismic network managers to decrease the number of errors that may lead to misorientations in future deployments.〈/span〉

Description: The geological disposal of high-level radioactive waste (hereinafter referred to "geological disposal") is a long-term, complex, and systematic scientific project, whose data and information resources in the research and development ((hereinafter referred to ”R&D”) process provide the significant support for R&D of geological disposal system, and lay a foundation for the long-term stability and safety assessment of repository site. However, the data related to the research and engineering in the sitting of the geological disposal repositories is more complicated (including multi-source, multi-dimension and changeable), the requirements for the data accuracy and comprehensive application has become much higher than before, which lead to the fact that the data model design of geo-information database for the disposal repository are facing more serious challenges. In the essay, data resources of the pre-selected areas of the repository has been comprehensive controll...

Description: 〈span〉〈div〉ABSTRACT〈/div〉To ensure the accuracy of future seismological studies using horizontal‐component data recorded by broadband seismic stations in Africa and environs, we investigate the sensor orientation of 1075 stations belonging to 41 seismic networks deployed in and around the African continent in the past three decades. We applied three independent waveform‐based orientation estimation methods that involve the measurement of 〈span〉P〈/span〉‐wave particle motion based on the principal component analysis, minimizing the 〈span〉P〈/span〉‐wave energy on the transverse component of motion, and measuring intermediate‐period Rayleigh‐wave arrival angles from teleseismic earthquakes. We found that 34.3%–43.5% of the stations are well oriented within 3°, 40%–48.2% have sensor misorientation values between 3° and 10°, whereas 16.5%–18% of the stations are misaligned by more than 10°, most likely true sensor misorientation. The fairly high correlation coefficients (0.71–0.93) and very small mean (−0.01°–0.06°) and median (−0.04°–0.3°) differences suggest a high consistency among the estimates from the three methods. Likewise, the comparison of our results with reported orientations in the metadata at 33 stations demonstrates the robustness of the results obtained in this study. Likewise, the increase in the cross‐correlation coefficients and reduced time shifts between the Rayleigh‐wave signals on the vertical and Hilbert‐transformed radial components when the sensor misorientation angles are corrected show the importance of this study. An investigation of the time dependence of the estimated misorientation angles over the validation period reveals that the sensor orientation remained fairly constant for most stations included in the study. The nearly 180° sensor misorientation angles obtained at some stations led to the suspicion of possible polarity reversal of the seismometer components and/or channel mislabeling that was confirmed with a network manager for two of the seismic stations. Result of this study serves as a reference for future data users and a reminder to seismic network managers to decrease the number of errors that may lead to misorientations in future deployments.〈/span〉

Description: The increased exposure of human populations to heat stress is one of the likely consequences of global warming, and it has detrimental effects on health and labor capacity. Here, we consider the evolution of heat stress under climate change using 21 general circulation models (GCMs). Three heat stress indicators, based on both temperature and humidity conditions, are used to investigate present-day model biases and spreads in future climate projections. Present day estimates of heat stress indicators from observational data shows that humid tropical areas tend to experience more frequent heat stress than other regions do, with a total frequency of heat stress 250?300 d yr ?1 . The most severe heat stress is found in the Sahel and south India. Present-day GCM simulations tend to underestimate heat stress over the tropics due to dry and cold model biases. The model based estimates are in better agreement with observation in mid to high latitudes, but this is due to compens...

Description: With rapid growth in the production of high concentration phosphate and compound fertilizers in China, PG production is increasing every year. However, its utilization is not increasing at the same pace. Phosphogypsum is usually stored in such a way that not only it occupies lot of land, but also leads to minimal environmental pollution. This paper summarized the policies, standards and managements issues associated with PG utilization, and in order to help the PG utilization and management effectively.

Description: Phosphogypsum (PG) is a radioactive industrial by-product produced in large quantities when processing phosphate ores into fertilizers. With rapid growth of high concentration phosphate and compound fertilizers production in China, PG production is increasing every year. Phosphogypsum is usually stored in such a way that it not only occupies a large piece of land, but also leads to environmental pollution. Utilization approaches of PG are put forward in this document in order to provide the scientific support for the effective utilization.

Description: Biological enzymes are catalyzed by living cells, most of which are proteins, and very few are RNA. Biological engineering as a new high-tech has been rapid development, Enzyme manufacturing and application areas are gradually expanding, In this paper, the status and progress of the application of enzyme technology are reviewed by reviewing the literature. and aims to provide reference for the application of enzyme technology and provide scientific basis for its future research and development in new field.

Description: In order to understand the characteristics of water supply and water usage in Beijing in recent 15 years, a variety of statistical datasets were collected and field investigations were carried out, to analyze the total water resource, the characteristics and trends of water resource supply, utilization and distribution during 2000-2014. The results showed that the total amount of water resources in Beijing is maintained at 1.61~3.95 billion m 3 , and the surface water accounts for about 1/3, and the groundwater accounts for 2/3. Agricultural water and living water were the dominated consumption in the past 15 years in Beijing, accounted for 35.3% and 38.9% of the total amount, followed by industrial water, which accounting for 17.9% of total water consumption, and water used in environment is relatively small, only accounting for 7.8% of the total amount. This study can provide theoretical support for the establishment and management of water conservation policies and t...

Description: A 4-year experiment was conducted to investigate the inter-annual effects of sandy soil amendment on maize yield, soil water storage and soil enzymatic activities in sandy soil in Northeast China in 2010 to 2014. We applied the sandy soil amendment in different year, and investigated the different effects of sandy soil amendment in 2014. There were six treatments including: (1) no sandy soil amendment application (CK); (2) one year after applying sandy soil amendment (T1); (3) two years after applying sandy soil amendment(T2); (4) three years after applying sandy soil amendment(T3); (5)four years after applying sandy soil amendment(T4); (6) five years after applying sandy soil amendment (T5). T refers to treatment, and the number refers to the year after application of the sandy soil amendment. Comparing with CK, sandy soil amendments improved the soil water storage, soil urease, invertase, and catalase activity in different growth stages and soil layers, the order of soil water...