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New Alkoxyzinc Salts Mediated Chemoselective Transesterification Reactions
Chemoselective transesterification zinc bromide zinc acetate alkoxyzinc bromide alkoxyzinc acetate
2010/4/19
A new chemoselective method for the transesterification of alkyl esters in the presence of in situ formed alkoxyzinc salts was developed. Electron-rich esters are less reactive than electron poor ones...
Flavonol Glycosides from Asperula arvensis L.
Asperula arvensis Rubiaceae flavonol glycosides quercetin isoquercitrin hyperin quercetin 7-O-b -galactopyra\-noside, quercetin 4'-O-b-galactopyra\-noside, isorhamnetin 3-O-b-galactopyra\-noside, isorhamnetin 5-O-b -galactopyra\-noside, dihydrokaempferol 7-4'-dimethylether 3-O-b -glucopyra\-noside isorhamnetin 3-O-a -rhamnopyranosyl (1''' \to 6'')-b-glucopyranosid
2010/4/20
From the aerial parts of Asperula arvensis L. 9 known flavonol glycosides, namely quercetin (1), isoquercitrin [= quercetin 3-O-b-glucopyranoside] (2), hyperin [= quercetin 3-O-b -galactopyranoside] (...
应用FTIR直接测定法鉴定大豆的品种
傅里叶变换红外光谱 直接测定 大豆 品种鉴定
2010/3/22
利用傅里叶变换红外光谱(FTIR)法测定了8个不同大豆品种的子叶及外表皮的红外光谱，对他们的红外光谱进行了分析，并对其吸收峰进行了归属。通过对各谱图的比较分析发现，不同的大豆品种的红外吸收峰形及峰强有所区别。结果表明： 不同的大豆品种的FTIR有明显的差别，特别是1 800～1 200 cm-1范围内有较大的差异，它反映的主要是蛋白质分子的酰胺Ⅰ带及酰胺Ⅱ带附近，这可能是源于基因的差异。因此FTI...
Defect Structure and Properties of Sr-Doped La Cr O3-d
Defect modeling LSC Perovskite Nonstoichiometry Conductivity
2010/4/20
A defect chemical model for the behavior of acceptor-doped LaCrO3 as a function of oxygen pressure is proposed. This is considered within the regime that corresponds to oxygen deficit oxygen. The math...
Formation of the Monolithic Silica Gel Column with Bimodal Pore Structure
Monolithic silica gel column Phase separation Sol-gel transition Pore structure
2010/4/20
A biporous monolithic silica gel column possessing both micrometer sized through-pores and nanometer sized mesopores located in the silica skeletons was prepared and the high concentration porogen (e....
The Second and Third Density Virial Coefficients of Six Ar-Ne Mixtures at 25.0°C
Ar--Ne mixtures second virial coefficient third virial coefficient
2010/4/22
In this paper we present a detailed experimental study of fractions, xAr = 0.0821, 0.2727, 0.3618, 0.5838, 0.7722 and 0.9049 at 25.0°C. The pressures are measured with a dead -- weight tester. The den...
Hydrothermal and Microwave Synthesis of Boron Phosphate, BPO4
Boron Phosphate BPO4 Microwave Synthesis Hydrothermal synthesis
2010/4/22
BPO4 was previously synthesized by the solid state reactions of (NH4)2HPO4 and B2O3 at 1000 oC and was characterized by X-ray powder diffraction and IR methods. We have now succeeded in preparing BPO4...
Heavy Metal Contents of Lake Sapanca
Drinking water Natural lakes Motorway Metal pollution
2010/4/23
The heavy metal pollution of Lake Sapanca located in the Marmara region (Turkey), was investigated over time. The lake is the drinking water source of the city of Adapazarı and its environs. The ...
Adsorption of Non-ionic Surface Active Agent on Fine Coal and Lignite
Reagent adsorption adsorption kinetics coal-lignite
2010/4/23
The adsorption of Triton X-100 in aqueous solution on the less than 53 \mm size fractions of Tunçbilek lignite and Zonguldak bituminous coal was studied. The adsorption isotherms were formed fo...