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81.
Protein separation and surfactant control of electroosmotic flow in poly(dimethylsiloxane)-coated capillaries and microchips 总被引:3,自引:0,他引:3
Badal MY Wong M Chiem N Salimi-Moosavi H Harrison DJ 《Journal of chromatography. A》2002,947(2):277-286
A thermally pyrolyzed poly(dimethylsiloxane) (PDMS) coating intended to prevent surface adsorption during capillary electrophoretic (CE) [Science 222 (1983) 266] separation of proteins, and to provide a substrate for surfactant adsorption for electroosmotic mobility control was prepared and evaluated. Coating fused-silica capillaries or glass microchip CE devices with a 1% solution of 100 cSt silicone oil in CH2Cl2, followed by forced N2 drying and thermal curing at 400 degrees C for 30 min produced a cross-linked PDMS layer. Addition of 0.01 to 0.02% Brij 35 to a 0.020 M phosphate buffer gave separations of lysozyme, cytochrome c, RNase, and fluorescein-labeled goat anti-human IgG Fab fragment. Respective plates/m typically obtained at 20 kV (740 V cm(-1)) were 2, 1.5, 1.25, and 9.4-10(5). In 50 mM ionic strength phosphate, 0.01% Brij 35 running buffer, the electroosmotic flow observed was about 25% of that in a bare capillary, and showed no pH dependence between pH 6.3-8.2. Addition of sodium dodecylsulfate (SDS) or cetyltrimethylammonium bromide (CTAB) to this running buffer allowed ready control of electroosmotic mobility, mu(eo). Concentrations of SDS between 0.005 to 0.1% resulted in mu(eo) ranging from 3 to 5 x 10(-4) cm2 V(-1) s(-1). Addition of 1 to 2.3 x 10(-4)% (2.7-6.3 microM) CTAB caused flow reversal. CTAB concentrations between 3.5 x 10(-4) and 0.05% (0.0014-1.37 mM) allowed control of mu(eo) between -1 x 10(-4) and -5.0 x 10(-4) cm2 V(-1) s(-1). For both surfactants the added presence of 0.01% Brij 35 provided slowly varying changes in mu(eo) with charged surfactant concentration. 相似文献
82.
Alexander V. Abanin Pham Trong Tien 《Journal of Mathematical Analysis and Applications》2010,363(1):296-301
As it is known, Roumieu-Komatsu theory of ultradistributions is strictly larger than Beurling-Björck one and that the latter theory is established by the class of all subadditive weight functions. In its own turn, Roumieu-Komatsu theory is equivalent to Braun-Meise-Taylor one which is given by the class of all weight functions. We prove that the class of all almost subadditive weight functions forms Braun-Meise-Taylor theory of ultradistributions. 相似文献
83.
To consider existence of solutions to various optimization-related problems, we first develop some equivalent versions of invariant-point theorems. Next, they are employed to derive sufficient conditions for the solution existence for two general models of variational relation and inclusion problems. We also prove the equivalence of these conditions with the above-mentioned invariant-point theorems. In applications, we include consequences of these results to a wide range of particular cases, from relatively general inclusion problems to classical results as Ekeland’s variational principle, and practical situations like traffic networks and non-cooperative games, to illustrate application possibilities of our general results. Many examples are provided to explain advantages of the obtained results and also to motivate in detail our problem settings. 相似文献
84.
Three‐Dimensional Ordered Assembly of Thin‐Shell Au/TiO2 Hollow Nanospheres for Enhanced Visible‐Light‐Driven Photocatalysis 下载免费PDF全文
Cao‐Thang Dinh Hoang Yen Prof. Freddy Kleitz Prof. Trong‐On Do 《Angewandte Chemie (International ed. in English)》2014,53(26):6618-6623
An Au/TiO2 nanostructure was constructed to obtain a highly efficient visible‐light‐driven photocatalyst. The design was based on a three‐dimensional ordered assembly of thin‐shell Au/TiO2 hollow nanospheres (Au/TiO2‐3 DHNSs). The designed photocatalysts exhibit not only a very high surface area but also photonic behavior and multiple light scattering, which significantly enhances visible‐light absorption. Thus Au/TiO2‐3 DHNSs exhibit a visible‐light‐driven photocatalytic activity that is several times higher than conventional Au/TiO2 nanopowders. 相似文献
85.
Tan Phat Nguyen Thi Thao Vy Tran Dinh Tri Mai Tien Dung Le Nhat Minh Phan Trong Dat Bui 《Natural product research》2015,29(15):1432-1436
From the leaves of Schefflera sessiliflora De P. V., one new C20-gibberellin diterpene 2β,12β-dihydroxygibberellin (12β-hydroxy-GA110 or 2β-hydroxy-GA112) (1), together with three known compounds, trans-tiliroside (2), kaempferol 3-O-β-d-glucuronopyranoside (3), 5-p-trans-coumaroylquinic acid (4), was isolated for the first time from the genus Schefflera by various chromatography methods. Their structures were elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments and comparison with previous reported data. The α-glucosidase inhibitory activity of all compounds was measured. The isolates (2, 3) showed better α-glucosidase inhibitory activity (IC50 = 134.60, 147.10 μM, respectively) than the standard drug acarbose (IC50 = 214.50 μM). 相似文献
86.
87.
V. V. Tkachev G. V. Shilov S. M. Aldoshin Yu. A. Sayapin Duong Nghia Bang V. N. Komissarov V. I. Minkin 《Russian Journal of Organic Chemistry》2011,47(9):1329-1334
The molecular structures of 9,11-di-tert-butyl-2,4-dimethyl-7H-12-oxa-3,7-diazapleiadene and 7-acetyl-9,11-di-tert-butyl-2,4,6-trimethyl-7H-12-oxa-3,7-diazapleiadene were determined by X-ray analysis. 相似文献
88.
89.
In this paper, we introduce a localized version of generalized normal maps as well as generalized natural mappings. By using
these concepts, we study continuity properties of the solution map of parametric variational inequalities in reflexive Banach
spaces. This localization permits us to deal with variational conditions posed on sets that may not be convex and to establish
existence and continuity of solutions. We also establish homeomorhisms between the solution set of variational inequalities
and the solution set of generalized normal maps. Using these homeomorphisms and the degree theory, we show that the solution
map of parametric variational inequalities is lower semicontinuous. Our results extend some results of Robinson (Set-Valued
Anal 12:259–274, 2004).
The authors wish to express their sincere appreciation to Professor Stephen M. Robinson, Department of Industrial and Systems
Engineering, University of Wisconsin-Madison, for his valuable comments and suggestions. This research was partially supported
by a grant from National Science Council of Taiwan, ROC. 相似文献
90.
Kuo‐Huai Kuo Yu‐Hsiang Peng Wen‐Yen Chiu Trong‐Ming Don 《Journal of polymer science. Part A, Polymer chemistry》2008,46(18):6185-6197
High loading of stable carbon black (CB) dispersion in organic solvent, PGMEA, was prepared by a ball‐milling process when using poly(styrene‐EHA‐HEMA)‐block‐poly(styrene‐EHA‐HEMA‐DMAEMA) (P(SEH)‐b‐P(SEHD)) as a dispersant. The P(SEH)‐b‐P(SEHD) containing P(SEH) as a steric chain and P(SEHD) as an anchoring chain was prepared by TEMPO‐mediated polymerization. The tertiary amine group of DMAEMA in P(SEHD) chain could be adsorbed onto CB by the interaction with the carboxylic acid group on surface of CB and the P(SEH) chain could provide sufficiently steric repulsion force to avoid the aggregation of CB. In addition, a photosensitive dispersant, P(SEH)‐b‐P(SEHD)C?C, containing the methacrylate double bond side group was also synthesized and was used to prepare stable CB dispersion in PGMEA. The effects of the molecular weight between steric and anchoring chains, the content of tertiary amine, and the amount of methacrylate double bond in the dispersant on the particle size of CB were investigated. Furthermore, the influences of various surface properties of CB, such as specific surface area, content of carboxylic acid group, and size of primary particle, on the particle size of CB in dispersion were also discussed. Finally, the photosensitivity of P(SEH)‐b‐P(SEHD)C?C/CB composite was monitored by a photodifferential scanning calorimeter. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6185–6197, 2008 相似文献