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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
F. Molaparast-Saless E. Shrago T. L. Spennetta S. Donatello L. M. Kneeland S. H. Nellis A. J. Liedtke 《Lipids》1988,23(5):490-492
A method has been developed for determination of individual long-chain fatty acyl-CoA esters from heart and skeletal muscle
using high performance liquid chromatography (HPLC). The esters were extracted from freezeclamped tissue of pig and rat hearts
and rat skeletal muscle for analysis on a radially compressed C18 5μ reversephase column. Nine peaks in the extract with carbon chain lengths from C12 to C20 that subsequently disappeared on alkaline hydrolysis were identified. The major acyl-CoA peaks were 14∶1, 18∶2, 16∶0 and
18∶1 and additionally in rat heart 18∶0. Total long-chain acyl-CoA esters obtained by summation of the individual molecular
species was 11.34±1.48 nmol/g wet wt. pig heart; 14.51±2.11 nmol/g wet wt. in rat heart, and 4.35±0.71 nmol/g wet wt. in rat
skeletal muscle. These values were approximately 132% of those obtained using a separate procedure that measured total CoA
by HPLC after alkaline hydrolysis of the esters. The described method demonstrates the quantitation of individual acyl-CoA
species in muscle tissue. Therefore, it has a number of advantages in that it permits information to be obtained on the individual
molecular species under various nutritional and metabolic conditions. 相似文献
992.
993.
994.
995.
Solubilities of Homologous and Isomeric Series Solubilities in water and organic solvents of homologous series of symmetrical dialkyl ketones (having no melting point alternations) and of β-phenyl,β-hydroxyl,β-alkyl-propionic acids (all with alternating melting points) were determined. In the case of medium chained dialkyl ketones the solubilities decrease in linear logarithmic proportion with increasing alkyl chain, according to the relationship of Erichsen. In isomeric series having systematically displaced substituents on n-paraffin C22H46, the maximum solubilities correspond to lowest melting points. In this case a quantitative relationship can not be formulated. 相似文献
996.
997.
C. L. Bristor 《Pattern recognition》1970,2(4):269-270
Spin scan cloud pictures from NASA's Applications Technology Satellites are being computer processed as an operational experiment. Details of this near-real-time image manipulating activity are described. Processing involves the treatment of horizon and landmark features in support of the photogrammetric aspects and the subsequent transformation of images onto standard map projections. 相似文献
998.
Support effects on hydrotreating catalysts 总被引:5,自引:0,他引:5
999.
We have adopted the flash method to the measurement of thermal diffusivity α of polymers in the temperature range 100–400K. The pulsed radiant energy from a flash tube is applied to the ‘front’ side of a suspended sample disc, and α is deduced from the exponential decay time constant of the subsequent transient temperature difference between the ‘front’ and the ‘back’ side, while correction against radiation loss is made by measuring the much longer decay time of the back-side temperature. Calibration runs on polycarbonate (PC) samples of several thicknesses show that the method is quick, precise and fairly accurate, and the results obtained are in reasonable agreement with previous determinations. We have also carried out measurements on polyoxymethylene (POM), poly (vinylidene fluoride) (PVF2) and poly (ethylene terephthalate) (PET) and computed their thermal conductivities. Results on POM and PVF2, which are semicrystalline, are analysed in the framework of several two-phase models, and the effect of crystallization (produced by annealing) on the glass transition behaviour of PET has also been studied. 相似文献
1000.
F. Yu. Abzgil'din R. A. Amirov A. Kh. Biglov L. B. Khoroshavin 《Refractories and Industrial Ceramics》1973,14(3-4):253-256
Conclusions A study of the adhesion and cohesion strength of refractory coatings based on oxides of titanium, zirconium, hafnium, silicon; nitrides of hafnium, boron, silicon; mullite, magnesia spinel, zirconates of calcium, barium, strontium; disulfide and disilicide of molybdenum, and calcium titanate, using phosphate bonds, established the optimum compositions for the coatings for the following alloys: 1Kh18N9T, Él-703, ÉP-99, VT-9, OT-4, ÉI-961, Br.Kh08 bronzes, molybdenum and graphite.Results are given for the working temperatures, shear strengths, and thermal-shock resistance of the coatings and also the electric conductivity and temperature conductivity of some compositions. The refractory coatings with phosphate bonds that were developed are recommended for use in high-temperature installations in the temperature range 1000–1800°C.Translated from Ogneupory, No. 4, pp. 50–54, April, 1973. 相似文献