ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Organic Chemistry  (10,863)
  • Life and Medical Sciences  (6,509)
  • Witterung
  • 1980-1984  (6,823)
  • 1975-1979  (5,291)
  • 1950-1954  (2,749)
  • 1935-1939  (2,543)
Collection
Publisher
Years
Year
  • 1
    ISSN: 1871-4528
    Keywords: Klima ; Witterung ; Qualität ; Trockenheit ; Sorte
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Description / Table of Contents: Summary The effect of chitting and planting time of potato seed on the suitability of the crop for crisp production was investigated in a 5-year trial. The second-early table variety Bintje and the two early-main crisping varieties Maritta and Saturna were used. Three chitting periods (0, 6 and 12 weeks) and two planting dates (the beginning of April and May) were investigated. The change in crisping quality over a 7–8 month storage period was checked by frying tests at two to two-and-a-half monthly intervals. The criterion of quality was the colour of the crisps. Duration of chitting had little effect on crisping quality. The effect of planting date was strongly affected by the weather in a given year. In most years, but not for the experiment overall, the colour rating of the chips was slightly but significantly better for the later rather than the earlier planting date. The two crisping varieties Maritta and Saturna reached optimum suitability for crisping about twothirds of the way through the storage period, i.e. about March, the late plantings showing a more marked improvement in quality than the early ones (Table 1, Fig. 1–4). The weather, sometimes in combination with various soil conditions, had the greatest influence on the experimental results. This is concluded since the effects of the individual experimental factors depend on the season (Fig. 1–4) and from the difference in the averaged yearly results. Statistical analysis showed highly significant years and all experimental factors but chitting. 1976 merits special attention due to the extremely warm and dry summer weather. Potatoes which at the start of storage were generally poor showed a great improvement in quality during storage, especially those from the later planting. From the results it is obvious that the producer of quality potatoes for industry faces difficulties in choosing growing methods for improving quality due to the unpredictability of the consequences of weather conditions.
    Abstract: Résumé L'influence de la durée de prégermination des plants et de la date de plantation sur l'aptitude des pommes de terre à la fabrication de pommes chips a été examinée dans un essai répété pendant 5 ans. Les cultivars ci-après ont été examinées: Bintje, variété mi-précoce de consommation, Maritta et Saturna, variétés mi-tardives présentant une très bonne aptitude à la fabrication de pommes chips. Trois procédés de prégermination (0, 6 et 12 semaines) ainsi que deux dates de plantations (début avril et début mai) ont été comparés. L'évolution de la qualité des chips au cours d'une durée de conservation de 7 à 8 mois, a été contrôlée à intervalles de deux mois à deux mois et demi, par des tests de fabrication. La couleur des pommes chips a constitué le critère de qualité. La prégermination n'a pratiquement pas influencé la qualité des chips. L'effet de la date de plantation était en relation étroite avec les conditions météorologiques de l'année. Sur un grand nombre d'années d'essais et compte tenu des exceptions, une amélioration peu importante mais néanmoins significantive de la qualité des chips, a été obtenue par la plantation tardive, par rapport à la plantation précoce. Pour les variétés spécifiquement aptes à la fabrication de chips, Maritta et Saturna, les tubercules ont atteint leur qualité optimale aux deux tiers de la durée de conservation, soit en mars environ. L'amélioration de la qualité a été plus prononcée pour les tubercules issus de la plantation tardive que pour ceux de la plantation précoce (tableau 1, fig. 1–4). Ce sont les conditions de croissance et les différences de structure du sol qui ont influencé le plus les résultats de ces essais. L'effet de l'année sur les paramètres examinés a été évident (fig. 2–4). L'analyse statistique (tableau 1) donne une interaction hautement significative entre les années et les paramètres d'essais, exception faite de la prégermination. Les résultats de l'année 1976 méritent une attention particulière, en raison des températures élevées, de la sécheresse durant l'été. La qualité des tubercules a été plutôt médiocre en début de conservation. Par la suite, plusieurs lots, et particulièrement ceux de la plantation tardive, se sont fortement améliorés (fig. 3). Ces résultats démontrent pour la production de pommes de terre destinées à la transformation industrielle, les difficultés auxquelles se heurte le choix des techniques culturales appropriées, en raison des conditions météorologiques imprévisibles.
    Notes: Zusammenfassung Die in einem mehrjährigen Versuch (1973–1977) mit den Sorten Bintje, Maritta und Saturna geprüften Faktoren Vorkeimen und Pflanzzeitpunkt des Saatgutes sowie Lagerdauer des Erntegutes, übten folgende Einflüsse auf die Farbe von daraus hergestellten Pommes Chips aus: - Spätes Pflanzen (anfangs Mai) brachte in der Mehrzahl der Versuchsjahre eine leichte Verbesserung der Chipsfarbe bei jeweils mindestens zwei der drei Versuchssorten gegenüber frühem Pflanzen (anfangs April). - Die Vorkeimdauer hatte keinen Einfluss. - Mit zunehmender Lagerdauer trat mindestens bis zum Monat März bei den beiden Chips-Sorten Maritta und Saturna eine Qualitätsverbesserung ein, die bei den spätgepflanzten Varianten etwas deutlicher ausfiel als bei den frühgepflanzten. Die Ergebnisse wurden durch die Jahreswitterung und teils auch durch die Bodenbeschaffenheit stark beeinflusst.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The title compound, an analogue of [Leu5]-enkephalin with L-o-carboranylalanine replacing L-phenylalanine in position 4, was prepared by fragment condensation. The analogue has a 3-fold higher affinity for rat brain opiate receptors in the [3H]naloxone competition assay than natural [Leu5]-enkephalin. Like [Leu5]-enkephalin and Na-acetyl-[Leu5]-enkephalin, the N-terminal tripeptide fragment, H · Tyr-Gly-Gly · OH, had no melanotropic activity in the Rana pipiens frog skin assay.A convenient, direct synthesis of methyl t-butoxycarbonyl-L-propargylglycinate is described, and the 13C-NMR. spectra of L-o-carboranylalanine recorded. The procedure was extended to the preparation of BOC · Car-Leu · OMe from BOC · Pra-Leu · OMe. A number of new propargylglycine derivatives are reported.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The conversion of primary, secondary and vinylic halides to the two C-atoms homologated phenylselenomethyl ketones 8 is described. The method involves addition of the readily available phenylselenoacetaldehyde 5 to the Grignard reagents 9 and oxidation of the resulting β-hydroxy-selenides 10 (Scheme 3).
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Preparation of Stilbenyl Derivatives of 1,2,4-OxadiazolesSchiffs bases derived from 3- and 5-(p-formylphenyl)-phenyl-1,2,4-oxadiazoles and chloroanilines are reacted with various p-tolyl substituted aromatic heterocycles in the presence of dimethylformamide and potassium hydroxide to yield the corresponding heterocyclic substituted stilbenes (‘Anil synthesis’). The reactivity of 5-[4-(chlorophenylimino-methyl)phenyl]-3-phenyl-1,2,4-oxadiazoles is very low and side reactions will predominate.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: (Perhalomethylthio)heterocycles. XIX. Mitt.: s. [1]. . Acid-catalyzed substitutions on (perchlorofluoromethylthio)pyrroles and their agro-biological activitiesIn the presence of C4F9SO3H the (perhalomethylthio)pyrroles 1a-c react with Cl3-nFnCSCl (n = 1-3) to give mixtures of the 2,5- and 2,4-disubstituted pyrroles 2a-f and 3a-h. 2a and 3a react with CF3SCl (catalyst CF3SO3H) yielding 2,3,5-tris (trifloromethylthio)pyrrole (4a), which under similar conditions reacts further to give 2,3,4,5-tetrakis (trifluoromethylthio)pyrrole (5). As a by-product during the conversion of 3a to 4a 2,3,4-tris (trifluoromethylthio)pyrrole (4b) is formed. The pyrroles 2a, 4a and 5 form the mercury salts 6a-c; compound 5 yields also a silver salt 7. The 1H- and 19F-NMR. spectra are discussed and the agro-biological properties of the compounds investigated.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 62 (1979), S. 1451-1457 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A new way to vinylic ethers from acetalsAcetals react at low temperatures in presence of a Lewis acid (aluminium chloride or magnesium bromide) with tertiary amine to give in good yields the vinylic ethers corresponding to the elimination of one molecule of alcohol.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Addition Reaction of 3-Dimethylamino-2,2-dimethyl-2H-azirine with Phenylisocyanate and Diphenylketene3-Dimethylamino-2,2-dimethyl-2H-azirine (1a) reacts with carbon disulfide and isothiocyanates with splitting of the azirine N(1), C(3)-double bond to give dipolar, fivemembered heterocyclic 1:1 adducts. In some cases, these products can undergo secondary reactions to yield 1:2 and 1:3 adducts. In this paper it is shown that the reaction of 1a with phenylisocyanate also takes place by cleavage of the N(1), C(3)-bond, whereas with diphenylketene N(1), C(2)-splitting is observed.The reaction of 1a and phenylisocyanate in hexane at room temperature yields the 1:3 adduct 2 in addition to the trimeric isocyanate 3 (Scheme 1). A mechanism for the formation of 2 is given in Scheme 5. Hydrolysis experiments with the 1:3 adduct 2, yielding the hydantoins 4-6 and the ureas 7 and 8 (Schemes 3 and 5), show that the formation of this adduct via the intermediates d, e and f is a reversible reaction.The aminoazirines 1a and 1b undergo an addition reaction with diphenylketene to give the 3-oxazolines 14 (Scheme 8), the structure of which has been established by spectral data and oxidative degradation of 14a to the 3-oxazolin-2-one 15 (R1 — R2 — CH3, Scheme 9).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1H-NMR. Spectroscopic Analysis of Prochiral Allenic Esters Using Optically Active Europium Shift ReagentsThe prochiral allenic methyl esters 1-4 (cf. Scheme) show in the presence of 1 mol-equiv. tris[3-(heptafluorobutyryl)-(+)-camphorato]europium (III) (Eu (hfc)3) in 1,1,2-trichloro-1,2,2-trifluoroethane (TCFE) induced unlike 1H-NMR. shift differences (ΔΔδ) for the enantiotopic protons and methyl groups on C(4), respectively (cf. Fig. 2 and 3). This effect allows to determine directly the 2JH,H coupling constants of the geminal protons on C(4) of the allenic esters 1 (15.5 Hz) and 2 (14.5 Hz) (cf. Table 2).
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 62 (1979), S. 1466-1474 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Heterocyclic anellated derivatives of strychnine: Imidazo-, oxazolo- and (1,3-dioxolo)strychnineThe synthesis of imidazo-, oxazolo- and dioxolo-strychnine derivatives, anellated at the 2,3-position of the aromatic nucleus is described. The spectroscopic properties of these compounds and of some intermediates are given.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 62 (1979), S. 1475-1484 
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: UV.-irradiation of pivalic and isobutyric acid and their methyl esters as well as of α-hydroxy isobutyric and malonic acid in solution lead to chemically induced dynamic nuclear polarization (CIDNP.) of parent compounds and of various reaction products. CIDNP.-effects and product distributions confirm α-cleavage of the C(α), CO bond to be the major mode of photodecomposition. Scavenger experiments indicate that decomposition of the molecules from a triplet excited state is roughly equally or more probable than from a singlet excited state. Quantum yields of educt disappearance are also given for the methyl esters of pivalic and isobutyric acid.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...