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101.
Vadim A. Dubskikh Anna A. Lysova Denis G. Samsonenko Alexander N. Lavrov Konstantin A. Kovalenko Danil N. Dybtsev Vladimir P. Fedin 《Molecules (Basel, Switzerland)》2021,26(5)
Three new 3D metal-organic porous frameworks based on Co(II) and 2,2′-bithiophen-5,5′-dicarboxylate (btdc2−) [Co3(btdc)3(bpy)2]·4DMF, 1; [Co3(btdc)3(pz)(dmf)2]·4DMF·1.5H2O, 2; [Co3(btdc)3(dmf)4]∙2DMF∙2H2O, 3 (bpy = 2,2′-bipyridyl, pz = pyrazine, dmf = N,N-dimethylformamide) were synthesized and structurally characterized. All compounds share the same trinuclear carboxylate building units {Co3(RCOO)6}, connected either by btdc2– ligands (1, 3) or by both btdc2– and pz bridging ligands (2). The permanent porosity of 1 was confirmed by N2, O2, CO, CO2, CH4 adsorption measurements at various temperatures (77 K, 273 K, 298 K), resulted in BET surface area 667 m2⋅g−1 and promising gas separation performance with selectivity factors up to 35.7 for CO2/N2, 45.4 for CO2/O2, 20.8 for CO2/CO, and 4.8 for CO2/CH4. The molar magnetic susceptibilities χp(T) were measured for 1 and 2 in the temperature range 1.77–330 K at magnetic fields up to 10 kOe. The room-temperature values of the effective magnetic moments for compounds 1 and 2 are μeff (300 K) ≈ 4.93 μB. The obtained results confirm the mainly paramagnetic nature of both compounds with some antiferromagnetic interactions at low-temperatures T < 20 K in 2 between the Co(II) cations separated by short pz linkers. Similar conclusions were also derived from the field-depending magnetization data of 1 and 2. 相似文献
102.
Dr. Igor L. Dalinger Dr. Irina A. Vatsadze Dr. Tatyana K. Shkineva Dr. Alexandr V. Kormanov Dr. Marina I. Struchkova Dr. Kyrill Yu. Suponitsky Dr. Anatoly A. Bragin Dr. Konstantin A. Monogarov Dr. Valery P. Sinditskii Dr. Aleksei B. Sheremetev 《化学:亚洲杂志》2015,10(9):1987-1996
A new family of energetic compounds, nitropyrazoles bearing a trinitromethyl moiety at the nitrogen atom of the heterocycle, was designed. The desirable high‐energy dense oxidizers 3,4‐dinitro‐ and 3,5‐dinitro‐1‐(trinitromethyl)pyrazoles were synthesized in good yields by destructive nitration of the corresponding 1‐acetonylpyrazoles. All of the prepared compounds were fully characterized by multinuclear NMR and IR spectroscopy, as well as by elemental analysis. Single‐crystal X‐ray diffraction studies show remarkably high density. Impact sensitivity tests and thermal stability measurements were also performed. All of the pyrazoles possess positive calculated heats of formation and exhibit promising energetic performance that is the range of 1,3,5‐trinitroperhydro‐1,3,5‐triazine and pentaerythritol tetranitrate. The new pyrazoles exhibit positive oxygen balance and are promising candidates for new environmentally benign energetic materials. 相似文献
103.
Dr. Christin Kirst Jonathan Tietze Dr. Peter Mayer Prof. Dr. Hans-Christian Böttcher Prof. Dr. Konstantin Karaghiosoff 《ChemistryOpen》2022,11(3):e202100224
The different coordination behavior of the flexible yet sterically demanding, hemilabile P,N ligand bis(quinoline-2-ylmethyl)phenylphosphine ( bqmpp ) towards selected CuI, AgI and AuI species is described. The resulting X-ray crystal structures reveal interesting coordination geometries. With [Cu(MeCN)4]BF4, compound 1 [Cu2(bqmpp)2](BF4)2 is obtained, wherein the copper(I) atoms display a distorted square planar and square pyramidal geometry. The steric demand and π-stacking of the ligand allow for a short Cu⋅⋅⋅Cu distance (2.588(9) Å). CuI complex 2 [Cu4Cl3(bqmpp)2]BF4 contains a rarely observed Cu4Cl3 cluster, probably enabled by dichloromethane as the chloride source. In the cluster, even shorter Cu⋅⋅⋅Cu distances (2.447(1) Å) are present. The reaction of Ag[SbF6] with the ligand leads to a dinuclear compound ( 3 ) in solution as confirmed by 31P{1H} NMR spectroscopy. During crystallization, instead of the expected phosphine complex 3 , a tris(quinoline-2-ylmethyl)bisphenyl-phosphine ( tqmbp ) compound [Ag2(tqmbp)2](SbF6)2 4 is formed by elimination of quinaldine. The Au(I) compound [Au2(bqmpp)2]PF6 ( 5 ) is prepared as expected and shows a linear arrangement of two phosphine ligands around AuI. 相似文献
104.
Vera Yu Mishina Mikhail K. Gratchev Konstantin L. Anfilov Il'dar G. Mustafin Anna R. Bekker Edward E. Nifantyev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The effective methods of phosphorylation of complex systems with specifically orientated in space hydroxyl groups, namely dianhydro-D-mannitol(A), -D-sor-bitol(B), cyclodextrines(C), and cellulose(D) (A-D, where R=H), have been elaborated. 相似文献
105.
Konstantin Iakoubovskii 《Central European Journal of Physics》2009,7(4):645-653
This paper reviews major techniques of aligning carbon nanotubes, either during the growth or by the post-growth processing.
A number of post-processing alignment techniques are discussed, which employ mechanical stretching, fracture, compression,
friction, filtration, fiber drawing, gas flow, liquid crystals, Langmuir-Blodgett technique, acoustic, magnetic and electric
fields. The suitability of those techniques to industrial applications is analyzed.
相似文献
106.
107.
Dmitry V. Pasyukov Andrey Yu. Chernenko Konstantin E. Shepelenko Vadim V. Kutyrev Victor N. Khrustalev Victor M. Chernyshev 《Mendeleev Communications》2021,31(2):176-178
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108.
109.
Xilin Peng Augusto Morrone Konstantin Nikolaev Mark Kief Mark Ostrowski 《Journal of magnetism and magnetic materials》2009,321(18):2902-2910
In this paper, we investigated the effect of background base pressure, wafer-transferring time between process modules, and stack layer material selection on the current-in-plane giant magneto-resistive (CIP-GMR) interface properties and the resulted CIP-GMR performance. Experimental results showed that seed layer/AFM interface, AFM/pinned layer (PL) interface, pinned layer/Ru interface, and reference layer (RL)/Cu spacer interface are among the most critical ones for a CIP-GMR device. By reducing the background impurity level (water moisture and oxygen), optimizing the wafer process flow sequence, and careful stack-layer material selection, such critical interfaces in a CIP-GMR device can be preserved. Consequently, a much robust GMR performance control can be achieved. 相似文献
110.
Luis N. Coria Konstantin E. Starkov 《Communications in Nonlinear Science & Numerical Simulation》2009,14(11):3879-3888
In this paper we characterize a locus of compact invariant sets of the system describing dynamics of the permanent-magnet synchronous motor (PMSM). We establish that all compact invariant sets of this system are contained in the intersection of one-parameter set of ellipsoids and compute its parameters. In addition, localizations by using a parabolic cylinder, an elliptic paraboloid and a hyperbolic cylinder are obtained. Simple polytopic bounds are derived with help of these localizations. Most of localizations mentioned above remain valid for more specific motor systems; namely, for the interior magnet PMSM and for the surface magnet PMSM. Yet another localization set for the interior magnet PMSM is described. Examples of localization of chaotic attractors existing for some values of parameters of PMSMs are presented as well. 相似文献