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Quantitative determination of the fatty acid composition of human serum lipids by high-performance liquid chromatography 总被引:2,自引:0,他引:2
A high-performance liquid chromatographic method for the analysis of the fatty acid composition of human serum lipids with fluorescence detection was examined. Both free and total fatty acids extracted from serum were derivatized with 9-anthryldiazomethane and were analysed using methanol-water (94.7:5.3) as mobile phase. Twelve kinds of fatty acid were detected, both in the free and total fatty acids, and were well separated. Concentrations of individual fatty acids of serum lipids were estimated from an internal standard, heptadecanoic acid. The results correlated well with those from two other quantitative analyses. These results indicate that the high-performance liquid chromatographic analysis of fatty acids is a reliable method for determining individual fatty acids of human serum lipids. The compositions of free fatty acids and total fatty acids of serum lipids were analysed and compared in 27 normal subjects, 27 diabetics, and 20 angina pectoris patients by this method. 相似文献
135.
Y Usui N Nishimura N Kobayashi T Okanoue M Kimoto K Ozawa 《Journal of chromatography. A》1989,489(2):291-301
A sensitive and precise method for measuring endogenous phylloquinone (K1) and menaquinone (MK-n) in human liver was developed, based on gradient elution high-performance liquid chromatography using platinum-black catalyst reduction and fluorimetric detection. Subnanogram levels of vitamin K compounds in 1 g of liver specimen were detectable. We measured vitamin K concentrations in 38 human resected livers. K1 and MK-4 to MK-13 were detected. The concentrations of MK-10 to MK-12 in livers with chronic hepatitis (n = 10) and cirrhosis (n = 22) were significantly lower than in normal livers (n = 6). It is suggested that the decreased concentrations indicate functional damage of the hepatocytes. 相似文献
136.
An air- and moisture-stable (pi-allyl)palladium complex bearing a unique diphosphinidenecyclobutene ligand effectively catalyzes amination reactions of aryl bromides with amines, where the reactions proceed under mild conditions without solvent, with 2 mol % of catalyst and 1 equiv of t-BuOK at room temperature. Under these conditions the amination products were obtained in good to excellent isolated yields. 相似文献
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An enhanced host–guest electro‐optical polymer system using poly(norbornene‐dicarboximides) via ROMP
Feng Yu Andrew M. Spring Lu Li Feng Qiu Kazuhiro Yamamoto Daisuke Maeda Masaaki Ozawa Keisuke Odoi Shiyoshi Yokoyama 《Journal of polymer science. Part A, Polymer chemistry》2013,51(6):1278-1284
High glass transition temperature poly(N‐cyclohexyl‐5‐norbornene‐2,3‐dicarboximide)s (NDI)s prepared by ring opening metathesis polymerization yielded polymers with a narrow polydispersity and well‐controlled molecular weight materials when using the Grubbs first generation initiator. Polymers produced using the Grubbs second generation initiator could not be controlled easily. By initiator selection it was also possible to synthesize polymers with either 98 or 52% trans microstructures. These materials were employed as electro‐optic (EO) polymer hosts for high molecular hyperpolarizability (β) phenyl vinylene thiophene vinylene bridge chromophores. This chromophore was modified by the incorporation of a tert‐butyldiphenylsilane group. The addition was able to further increase its EO coefficient (r33) to reach 93 pm/V in a trans rich poly(NDI) produced by the Grubbs first generation initiator, compared to a benchmark chromophore / polymer combination. We investigated in detail the relationship between polymer microstructure and their absolute molecular weight on forming the best host–guest with the high β chromophore. Our results indicate that by utilizing a very simple host–guest system a high r33 can be realized. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
139.
Preparation of ureido group bearing polymers and their upper critical solution temperature in water 下载免费PDF全文
Ami Fujihara Kohei Itsuki Naohiko Shimada Atsushi Maruyama Naoya Sagawa Toshiyuki Shikata Shin‐Ichi Yusa 《Journal of polymer science. Part A, Polymer chemistry》2016,54(18):2845-2854
Poly(2‐ureidoethylmethacrylate) (PUEMn) was synthesized via reversible addition‐fragmentation chain transfer (RAFT) radical polymerization and following polymer reaction. We prepared two PUEMn samples with different degrees of polymerization (n = 100 and 49). The polymers exhibited upper critical solution temperature (UCST) in phosphate‐buffered saline (PBS) solution. The phase separation temperature (Tp) in PBS can be controlled ranging from 17 to 55 °C by changing molecular weight of the polymer, polymer concentration, and adding NaCl concentration. The polymers in PBS formed coacervate drops by liquid–liquid phase separations below Tp. Results of the dielectric relaxation measurement, the hydration number per monomeric unit was 5 above Tp. Based on a fluorescence study, the polymer formed slightly hydrophobic environments below Tp. The liquid–liquid phase separation was occurred presumably because of weak hydrophobic interactions and intermolecularly hydrogen bonding interactions between the pendant ureido groups. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 2845–2854 相似文献
140.
Koji Ishizu Naoyuki Kobayakawa Satoshi Takano Yoko Tokuno Masaaki Ozawa 《Journal of polymer science. Part A, Polymer chemistry》2007,45(9):1771-1777
The crosslinked polystyrene particles possessing photofunctional N,N‐diethyldithiocarbamate groups on their surface were prepared by free‐radical emulsion copolymerization of a mixture of styrene, divinylbenzene and 4‐vinylbenzyl N,N‐diethyldithiocarbamate with redox system as an initiator under UV irradiation. In this copolymerization, the inimer 4‐vinylbenzyl N,N‐diethyldithiocarbamate acted the formation of hyperbranched structures by living radical photopolymerization. The particle sizes (number‐average particle diameter = 214–523 nm) were controlled by varying the feed amount of surfactant and size distributions were relatively narrow. Subsequently, core–shell particles were synthesized by photoinduced atom transfer radical polymerization approach of methyl methacrylate initiated by photofunctional polystyrene particles as a macroinitiator. Such core–shell particles were stabilized sterically by grafted chains in organic solvents. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1771–1777, 2007 相似文献