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151.
Software Quality Journal - Energy consumption of software has been becoming increasingly significant, since it can vary according to how the software has been developed. In recent years, developers... 相似文献
152.
Jean-Marie Degroodt Brigitte Wyhowski de Bukanski Sarah Srebrnik 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,195(6):566-568
Summary A method combining immunoaffmity-chromatography (IAC) and high-performance liquid chromatography (HPLC) for the analysis of Salbutamol in liver with a low quantification limit of 1 g/kg has been developed. Salbutamol was extracted with 0.01 mol/L HCl and purified by IAC. The samples were analysed on a liquid Chromatograph fitted with a C18 -Bondapak column. A fluorometer was used for the detection of salbutamol. Recoveries of 67–80% could be obtained.
Immunoaffinitätschromatographische Reinigung von Salbutamol in Leber und Rückstandsbestimmung mittels HPLC und fluorimetrischer Detektion
Zusammenfassung Eine Methode, die Immunoaffinitäts-und Hochleistungsflüssigchromatographie verbindet, ist für die Analyse von Salbutamol in Leber entwickelt worden. Eine niedrige Bestimmungsgrenze von 1 g/kg Leber wurde erreicht. Salbutamol wurde mit 0,01 mol/L Salzsäure freigesetzt und durch Immunoaffinitätschromatographie gereinigt. Die Proben wurden durch Flüssigchromatographie auf einer C18 -Bondapak-Säule analysiert. Ein Fluorimeter wurde für die Detektion von Salbutamol benutzt. Ausbeuten von 67 bis 80% konnten erreicht werden.相似文献
153.
Data are presented on the influence of prophylactic vitamin administration to schoolchildren in two schools on their health. The morbidity rate significantly decreased, the levels of lysozyme in the saliva, hemoglobin in the blood and total protein in the blood serum rose in the children who received multivitamin "Undevitum" during 5-7 months, as compared to those who were not given the vitamins. Vitamin administration did not influence the physical development of schoolchildren. 相似文献
154.
155.
C García Barroso R Cela Torrijos J A Pérez-Bustamante 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1987,185(4):307-314
The different groups and/or classes among phenolic acids and aldehydes identified during the elaboration process of "fino" sherry wine have been studied. The study was carried out using different processes during the elaboration of the wine and we have attempted to establish whether the different treatments of the grape affect these groupings. The study was undertaken by means of cluster and multifactorial analysis on the data obtained by the quantitative determination of phenolic acids and aldehydes during vinification and in experiments carried out on the grape under different mechanical treatments. The analysis of phenolic acids and aldehydes was done with HPLC, using a C-18 mu-Bondapak and a stepwise composite gradient. The samples were previously extracted with ethylic ether. 相似文献
156.
Catalysis Letters - The NdM0.25Ni0.75O3 (M?=?Cr, Fe) named NCN and NFN catalysts precursors were synthesized and characterized. The CO2 utilization in the feed was studied in the... 相似文献
157.
Tin electrodeposition in its initial stages in acid sulfate/gluconate baths was studied with varying tin and gluconate concentrations using potential-controlled electrochemical techniques. The deposit morphology was observed by scanning electron microscopy (SEM). A comparison with tin electrodeposition from acid sulfate baths in the absence of gluconate was also carried out. Use of a highly acidic bath leads to nonuniform deposits, even in the presence of gluconate; at pH 4 deposits are uniform, brilliant and suitable for finishing applications. Tin crystallites have a well defined morphology which depends on bath agitation conditions. In the absence of agitation, the crystallites have the same tetragonal shape as in a sulfate bath without gluconate. 相似文献
158.
A new crystalline structure of poly 4-methylpentene-1 (P4MP1), modiification named modification V, is obtained from cyclopentane solutions and gels, for polymer volume fractions between 0.01 and 0.10. The effect of the thermal history imparted to the solution is analyzed. The relation between gelation, polymorphism and existence of helical conformations of P4MP1 in solution is discussed. Modification V is tentatively indexed on the basis of an hexagonal unit cell with dimensions a = 22.17 ± 0.14 Å and c = 6.69 ±0.02 Å. The crystal transforms into modification I at 130 ± 5°C, the heat of transition being + 15 ±2 J.g?1. 相似文献
159.
C. Okkerse A. de Jonge J. W. E. Coenen A. Rozendaal 《Journal of the American Oil Chemists' Society》1967,44(2):152-156
Many investigators associate the poor keeping properties of soybean oil with its linolenic acid content. On the other hand
the high linoleic acid content is a desired property from a nutritional point of view. We have therefore developed a process
for the preferential reduction of the linolenic acid content by selective hydrogenation. Conventional catalysts for the hydrogenation
of fats have a rather low selectivity in this respect. When linolenic acid in soybean oil is hardened (e.g., with a nickel
catalyst), most of the linoleic acid is converted into less unsaturated acids.
It was found that linolenic acid is hydrogenated much more preferentially in the presence of copper catalysts than in that
of nickel and other hydrogenation catalysts. At a linolenic acid content of 2%, soybean oil hardened with nickel catalyst
contained about 28% linoleic acid, whereas with copper catalyst the hardened soybean oil contained 49% linoleic acid.
By means of our process it is possible to manufacture a good keepable oil of, e.g., I.V. 115 and containing 1% linolenic acid
and 46% linoleic acid. The storage stability of this product is comparable with that of sunflower-seed oil. A liquid phase
yield of 86% is obtained after winterization at 5C for 18 hr.
The high selectivity for linolenate reduction of copper catalysts must be ascribed to the copper part of the catalyst. Investigations
into the structure of the catalyst indicate that the active center consists of copper metal crystallites; whether these centers
are promoted by the carrier or traces of other substances is under investigation. 相似文献
160.
M A Rossi S Zucoloto J E Dutra de Oliveira P F Becker J S Oliveira 《Archivos latinoamericanos de nutrición》1978,28(1):29-40
A study of the effect of long-term alcohol consumption on the liver of well-nourished rats is described. Rats fed for 16 weeks on a semipurified diet supplemented with high levels of vitamins and lipotropic factors and alcohol corresponding to 35% of the total caloric intake developed marked fatty changes of the liver. Mild fatty changes were observed in pair-fed controls receiving as isoenergetic equivalent of sucrose instead of alcohol. Intracellular hyaline bodies, corresponding ultrastructurally to giant mitochondria were abundantly found in the hepatocytes of alcoholic rats, while in the controls they were not seen. Te findings in this investigation are postulated to provide further evidence that the long-term intake of alcohol exerts a direct causative role in the pathogenesis of liver damage. 相似文献