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81.
从讨论影响脂肪肝的主要因素排序出发,应用简明统计分析,给出了辅助医学诊断中用于判断患者患脂肪肝的可能性,由此,对于可能性为零的情形可以排除进一步的生化检查,也就不会发生相应的感染. 相似文献
82.
Laurent Aubry Thierry Sayd Claude Ferreira Christophe Chambon Annie Vnien Sylvie Blinet Marie Bourin Anglique Travel Maeva Halgrain Vronique Sant-Lhoutellier Laetitia Thron 《Molecules (Basel, Switzerland)》2021,26(12)
The marketing of poultry livers is only authorized as fresh, frozen, or deep-frozen. The higher consumer demand for these products for a short period of time may lead to the marketing of frozen–thawed poultry livers: this constitutes fraud. The aim of this study was to design a method for distinguishing frozen–thawed livers from fresh livers. For this, the spectral fingerprint of liver proteins was acquired using Matrix-Assisted Laser Dissociation Ionization-Time-Of-Flight mass spectrometry. The spectra were analyzed using the chemometrics approach. First, principal component analysis studied the expected variability of commercial conditions before and after freezing–thawing. Then, the discriminant power of spectral fingerprint of liver proteins was assessed using supervised model generation. The combined approach of mass spectrometry and chemometrics successfully described the evolution of protein profile during storage time, before and after freezing-thawing, and successfully discriminated the fresh and frozen–thawed livers. These results are promising in terms of fraud detection, providing an opportunity for implementation of a reference method for agencies to fight fraud. 相似文献
83.
Characterization of Silver Flake Lubricants 总被引:2,自引:0,他引:2
There is a thin layer of organic lubricant on commercial silver (Ag) flakes that are widely used as the fillers in electrically
conductive adhesives (ECAs). This lubricant layer highly affects the properties such as conductivity of the ECAs. Therefore,
understanding the behavior of Ag flake lubricant layer is essential for developing high performance ECAs. This work is aimed
at studying the chemical nature of the lubricant layer, interaction between the lubricant layer and Ag flakes, and thermal
behavior of the lubricants during heating. A blank Ag powder is ball-milled into Ag flakes with five fatty acids that have
different carbon–hydrogen chain length as lubricants. After lubrication, the Ag flakes are studied using scanning electron
microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetry (TG), and diffuse reflectance infrared Fourier
transform spectroscopy (DRIFTS). It is found that (i) Ag flakes lubricated with fatty acids of different chain lengths have
exothermic DSC peaks and mass losses at different temperatures, (ii) the lubricant layer on the lubricated Ag flake surfaces
is a salt formed between the acid and Ag, and (iii) exothermic DSC peaks (in air) of a lubricated Ag flake is probably due
to the oxidation of lubricant layer on the Ag flake surface.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
84.
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87.
The effect of pH on the separation of manure nutrients with reverse osmosis membranes 总被引:2,自引:0,他引:2
This paper reports on the effect of pH on the retention of dry matter (DM), total ammonia-nitrogen (TAN), potassium, phosphorus and volatile fatty acids (VFAs) during the filtration of pretreated swine manure by three highly selective reverse osmosis (RO) membranes. The manure was pretreated using various combinations of biological and physical technologies, namely anaerobic digestion (AD), vacuum filtration through diatomaceous earth (DE), nanofiltration (NF), and a first stage RO filtration. The objective was to establish the level of acidification required to optimize permeate quality while minimizing chemical addition. 相似文献
88.
89.
Hatice Mutlu Michael A. R. Meier 《Journal of polymer science. Part A, Polymer chemistry》2010,48(24):5899-5906
The ring‐opening metathesis polymerization (ROMP) of fatty acid functionalized norbornenes was explored in the presence of dichloro[1,3‐bis(2,4,6‐trimethylphenyl)‐2‐imidazolidinylidene](benzylidene)bis(3‐bromopyridine)ruthenium(II) ( C3 ) at room temperature. The investigated monomers were derived from fatty acids with different chain lengths (C6, C8, C10, C12, C14, C16, and C18) and can therefore contribute to the development of more sustainable, bio‐based polymeric materials. The polymerizations initiated by C3 proceeded in a living fashion with good initiation efficiency, and thus the synthesis of well‐defined polymers with narrow polydispersities was accomplished. All prepared polymers were fully characterized (GPC, DSC, TGA, NMR) and the results of these investigations are discussed within this contribution. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
90.
In order to better understand the metabolic fate of n-3 polyunsaturated fatty acids (PUFAs), an efficient access to symmetrical and unsymmetrical triacylglycerols (TGs), esterified with PUFAs, with known high purity, is required. In this context, we optimized the esterification of a mixture of glycerols protected as dioxane and dioxolane with PUFAs. The kinetics of this reaction depends on various factors, such as the fatty acid chain length and the stereochemistry of the dioxane. Then, one-pot acetal hydrolysis and esterification of hydroxyl groups led to the desired structured TGs without either double bond isomerization or acyl migration (except when symmetrical TGs are acylated with long-chain saturated fatty acids in external positions). PUFAs location on the glycerol backbone was assayed by NMR, HPLC and pancreatic lipase hydrolysis. 相似文献