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991.
992.
Akito Tsuboi 《Mathematical Logic Quarterly》2001,47(1):45-50
Let T1 and T2 be two simple complete theories in disjoint languages. We prove that there is a simple complete theory which extends T1 ∪ T2 if T2 has a certain condition. 相似文献
993.
Nori Yamaguchi Devdatt S. Nagvekar Harry W. Gibson 《Angewandte Chemie (International ed. in English)》1998,37(17):2361-2364
Like the proverbial monkey chain one heteroditopic self-complementary molecule, comprising a crown ether unit and a paraquat unit, catches a second such molecule in solution and thus by self-organization forms novel linear oligo- and polymolecular arrays (shown schematically; the crown ether unit is denoted by the ellipse, and the paraquat unit by the rectangle). 相似文献
994.
Makoto Fujita Shu-Yan Yu Takahiro Kusukawa Hidenori Funaki Katsuyuki Ogura Kentaro Yamaguchi 《Angewandte Chemie (International ed. in English)》1998,37(15):2082-2085
Nanometer-sized bowls: six metal centers and four tridentate ligands self-assemble in aqueous solution to give the macrotricycle 1 , which has approximate dimensions of 3×2×2 nm. Another macrocycle (not shown), obtained with a different ligand, is of similar size and topology but differs considerably from 1 in its host–guest behavior. 相似文献
995.
996.
997.
998.
Akira Yamaguchi Takashi Yoda Shintaro Suzuki Kotaro Morita Norio Teramae 《Analytical sciences》2006,22(12):1501-1507
The apparent diffusion coefficients of tris(2,2'-bipyridyl)ruthenium ([Ru(bpy(3))](2+)) are estimated in silica-nanochannels which are assembled inside columnar alumina pores in an anodic alumina membrane, and are modified with alkylsilanes such as trimethylchlorosilane (C1), butyldimethylchlorosilane (C4), and dodecyldimethylchlorosilane (C12). The estimation is performed by observing the lag-time, which is defined as the time required for [Ru(bpy)(3)](2+) to diffuse through alkylsilane-modified silica-nanochannels in the alumina membrane. When ethanol is used as a solvent, the apparent diffusion coefficients of [Ru(bpy)(3)](2+) are estimated as 2.1 x 10(-10) and 3.2 x 10(-10) cm(2) s(-1) in the C1- and C4-modified silica-nanochannels, respectively. These values are about 10(4) times smaller than that obtained in bulk ethanol. Based on the experimental results on the solvent dependency of the lag-time, the hydrogen-bonding interaction between ethanol molecules is considered to be stronger in the C1- and C4-modified silica-nanochannels than in bulk ethanol, and the hydrogen-bonding interaction plays a critical role for the slow diffusivity in those nanochannels. In contrast, the apparent diffusion coefficient in the C12-modified silica-nanochannel is at least two orders of magnitude larger than those in the C1- and C4-modified silica-nanochannels. This relatively fast diffusion is most likely explained by the presence of a long alkyl chain of C12, which reduces a hindrance effect that is originates in the hydrogen-bonding interaction. 相似文献
999.
Junpei Yamanaka Saiko Yamada Norio Ise Takuji Yamaguchi 《Journal of Polymer Science.Polymer Physics》1995,33(10):1523-1526
The isoionic dilution method, which was proposed by Pals and Hermans, for linear ionic polymer solutions, was examined for the viscosity behavior of dilute aqueous dispersion of ionic latex [particle diameter, (0.120 ± 0.003) × 10–6 m; surface charge density, 1.6 × 10–6 C/cm2] in the presence of sodium chloride (5 × 10–5 to 5 × 10–4 M). Linear relations were obtained between the reduced viscosity and the latex concentration, when a parameter m, which appeared in the effective ionic strength introduced by Pals and Hermans, was chosen to be about 0.1. This finding on the latex system does not support that, at the salt and polymer concentrations employed, the dimension of linear macroions varies with changing effective ionic strength and it is kept constant along the isoionic dilution line. Brief discussion on the m value is presented. ©1995 John Wiley & Sons, Inc. 相似文献
1000.
Ryuji Nakao Kenji Furutsuka Masatoshi Yamaguchi Kazutoshi Suzuki 《Analytical sciences》2007,23(2):151-155
A sensitive, selective and rapid high-performance liquid chromatographic (HPLC) method with chemiluminescence (CL) detection was developed and validated for the analysis of positron emission tomography (PET) radiopharmaceuticals. This method is based on the CL reaction of PET compounds with tris(2,2'-bipyridyl)ruthenium(II) [Ru(bpy)(3)(2+)] and acidic potassium permanganate [KMnO(4)]. After optimization of the reaction conditions, 12 of the 14 PET compounds investigated could be successfully detected and showed good performance in terms of sensitivity, linearity and reproducibility. In particular, for compounds with a tertiary amine functional group, the limits of detection were ppb levels for a 20 microL injection volume. Finally, this method was used to determine PET compounds for calculating of specific radioactivity in pharmaceutical samples. 相似文献