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1.
Abstract

3-Tetrahydrofurfuryloxy-2-hydroxypropyl methacrylate monomer was prepared from methacrylic acid, tetrahydrofurfuryl alchol, and epichlorhydrin. Homopolymerization and copolymerization with (2-phenyl-1,3-dioxolane-4-yl)methyl methacrylate and N-vinyl pyrrolidone monomers were carried out in 1,4-dioxane solution at 60°C using benzoyl peroxide as initiator. Infrared, proton and carbon-13 nuclear magnetic resonance techniques were used in characterizations of the monomer, the homopolymer and the copolymers were determined by DSC technique. The copolymer compositions were estimated from 1H-NMR spectra. The reactivity ratios in copolymerization of 3-tetrahydrofurfuryloxy-2-hydroxypropyl methacrylate and (2-phenyl-1,3-dioxolane-4-yl) methyl methacrylate were calculated by both Kelen-Tüdos and Fineman-Ross methods.  相似文献   
2.
The major limitation to fatty acid analysis by gas-liquid chromatography is associated with preparation of fatty acid methyl esters (FAME). In the present study, FAME preparations were made from plant oils (corn, olive, sunflower), sunflower oil margarine, lard and various animal tissue fats by a rapid transesterification involving tetramethylammonium hydroxide in methanol, and also by a longer conventional saponification-esterification method. Fats from animal (beef, mutton, pork) adipose tissues were extracted by a simpler modified procedure and also by the Folch method prior to the rapid and the conventional FAME preparations, respectively. FAME analysis on a gas-liquid chromatograph equipped with a Silar 10C glass capillary column indicated similar fatty acid composition of a given fat or oil, whether FAME was prepared by the rapid or the longer conventional method. The data obtained by both methods were very highly correlated for all the fats (r = 0.9895 - 0.9999). However, the rapid method showed a tendency for enhanced recoveries of lower chain fatty acids (e.g. 14:0), and also of unsaturated C18 isomers. Possibly, losses of fatty acids that occurred during the lengthy fat extraction, fatty acid esterification or ether-evaporation FAME concentration steps (conventional method) were minimised by the single transesterification step (rapid method). This rapid transesterification method appears to be an attractive alternative to FAME preparation from a wide variety of different fats for gas-liquid chromatographic analysis.  相似文献   
3.
In this paper we present an “iteration” technique for a class of differential equation having the form z=λz, where λ is a function in C. We show that we can construct not only the general solution of the reduced wave equation but also the general solution of the Riccati differential equation by using this iteration technique if the given function λ is satisfies the condition
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4.
5.
α-Haloesters containing the chalcone structure and α-haloamides containing the pyrazoline ring have been synthesized by reaction of substituted hydroxy chalcones and pyrazoline derivatives (prepared as reported elsewhere; J Chem 8(4):1574–1581, 2011) with chloroacetyl chloride in dry THF in the presence of Et3N. The structures of the synthesized compounds were confirmed by IR, 1H NMR, and (for some compounds) 13C NMR spectroscopy.  相似文献   
6.
Preparation of bisbenzofuran-2-yl-methanone (1), the corresponding ketoxime 4, semicarbazone and thiosemicarbazone 3a and 3b, ether derivatives of the ketoximes 5a-j and the alcohol 2 are described. These substances have been prepared in excellent yields. All the synthesized compounds except 5i have been tested against five different microorganisms and some of them were found to be active against some of the species studied.  相似文献   
7.
Two novel monodentate carbamate ligands derived mainly from 4‐(1‐methyl‐1‐phenylcyclobutyl‐3‐yl)‐2‐aminothiazole and 4‐(1‐phenyl‐1‐methylcyclobutane‐3‐yl)‐2‐(N‐methyl)aminothiazole, have been prepared. The ligands and their metal complexes have been characterized by elemental analyses, IR, 13C, and 1H NMR spectra, as well as UV–Vis, and magnetic susceptibility measurements. Both ligands contain 1 mole of water of crystallization and all complexes are mononuclear. Antimicrobial activities of the ligands and their complexes have been screened against the Bacillus subtitis IMG 22 (bacteria), Micrococcus luteus LA 2971 (bacteria), Escherichia coli DM (bacteria), Staphylococcus aureus COWAN I (bacteria), Saccharamyces cerevisiae UGA 102 (yeast), and Candida albicans CCM 314 (yeast). Thermal properties of the ligands and their complexes have been studied by thermogravimetric analyses (TGA) and differential scanning calorimetry (DSC). © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:665–670, 2001  相似文献   
8.
Two new hydroxyethyl methacrylates having aryl and cyclobutane rings were synthesized by addition to 1-(epoxyethyl)-3-aryl-3-methylcyclobutane to methacrylic acid. The monomers prepared are 2-(3-methyl-3-phenylcyclobutyl)-2-hydroxyethyl methacrylate (PCHEMA) and 2-(3-methyl-3-mesitylcyclobutyl)-2-hydroxyethyl methacrylate (MCHEMA). Both monomers were polymerized at 60°C in 1,4-dioxane solution using benzoyl peroxide as initiator. Poly(PCHEMA) and poly(MCHEMA) and their monomers were characterized by FT-IR and 1H- and 13C-NMR techniques. Weight average molecular weights of the polymers were determined for poly(PCHEMA) poly(MCHEMA) by gel permation chromatography. Thermal stabilities of the polymers were essentially the same. Glass transition temperatures for poly(PCHEMA) and poly(MCHEMA) were determined as 105 and 137°C, respectively. No changes of the polymers by irradiation with UV light at 254 nm were observed. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2123–2128, 1997  相似文献   
9.
10.
Abstract

Phenacylmethacrylate (PAMA), a new monomer containing two carbonyl groups (C[dbnd]O), was obtained from phenacyl chloride and sodium methacrylate. The homopolymer of PAMA and its copolymer with styrene were prepared in dioxane by using benzoylperoxide (Bz2O2) as initiator. IR, 1H-NMR and 13C-NMR techniques were used to identify the structure of the monomer and polymers. The density of monomer, homopolymer and copolymer were found to be 1.13; 1.35 and 1.10 gr/ml respectively. Also, limit viscosity numbers, solubility parameters, glass transition and decomposition temperatures of polymers were determined.  相似文献   
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