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151.
Abstract Double Stratonovich integrals with respect to the odd part and even part of the fractional Brownian motion are constructed. The first and the second moments of such integrals are explicitly identified. As application of double Stratonovich integrals a strong law of large numbers for efBm and ofBm is derived. Riemann–Stieltjes integral approximations to double Stratonovich fractional integrals are also considered. The strong convergence (almost surely and mean square) is obtained for approximations based on explicit series expansions of the fractional Brownian processes. The weak convergence is derived for approximations by processes with absolutely continuous paths which converge weakly to the considered fractional Brownian processes. The above-mentioned convergences are obtained for deterministic integrands which are given by bimeasures. 相似文献
152.
Xiaoming Jie Constantin G. Daniliuc Robert Knitsch Michael Ryan Hansen Hellmut Eckert Sebastian Ehlert Stefan Grimme Gerald Kehr Gerhard Erker 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(3):892-896
A new six‐membered cyclic frustrated phosphane/borane Lewis pair was liberated from its HB(C6F5)2 adduct by treatment with vinylcyclohexane. The system is an active frustrated Lewis pair that undergoes cycloaddition reactions with suitable π reagents and it splits dihydrogen. At room temperature in solution the new compound is a monomer, however, in the crystal and in solution at low temperature it aggregates to a thermodynamically favoured supramolecular macrocyclic cyclooctamer. 相似文献
153.
Dr. Jun Li Dr. Constantin G. Daniliuc Dr. Gerald Kehr Prof. Dr. Gerhard Erker 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6809-6813
Treatment of 1,3,5‐tris(trifluoromethyl)benzene with n‐BuLi, followed by H3B?SMe2 and subsequent hydride removal gave the (Fmes)BH2 reagent, which was isolated as a SMe2 stabilized monomer or a ligand free (μ‐H)2‐bridged dimer. Reaction with Mes2P(vinyl) gave the respective ethylene‐bridged P/B(Fmes)H FLP. It reduced carbon monoxide to the formyl stage and carbon dioxide to the formaldehyde oxidation state. Most new compounds were characterized by X‐ray diffraction. 相似文献
154.
Jun Li Constantin G. Daniliuc Christian Mück‐Lichtenfeld Gerald Kehr Gerhard Erker 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(43):15521-15524
The twofold hydroboration products of (Fmes)BH2?SMe2 with a series of alkynes (2‐butyne, arylethynes) react with two molar equiv of 2,6‐dimethylphenyl isocyanide (CN‐Xyl) at 80 °C to give rare examples of 1,3‐azaborinine derivatives. A mechanistic study revealed a reaction course involving insertion of one isonitrile followed by a bora‐Nazarov type ring‐closure reaction and subsequent isonitrile insertion to give the respective 1,3‐dihydro‐1,3‐azaborinines 5 . 相似文献
155.
Jindong Ren Marvin Cnudde Dana Brünink Stefan Buss Constantin G. Daniliuc Lacheng Liu Harald Fuchs Cristian A. Strassert Hong‐Ying Gao Nikos L. Doltsinis 《Angewandte Chemie (International ed. in English)》2019,58(43):15396-15400
A series of Pt(II) complexes with tetradentate luminophores has been designed, synthesized, and deposited on coinage metal surfaces with the aim to produce highly planar self‐assembled monolayers. Low‐temperature scanning tunneling microscopy (STM) and density functional theory (DFT) calculations reveal a significant initial nonplanarity for all complexes. A subsequent metal‐catalyzed separation of the nonplanar moiety at the bridging unit via the scission of a C?N bond is observed, leaving behind a largely planar core complex. The activation barrier of this bond scission process is found to depend strongly on the chemical nature of both bridging group and coordination plane, and to increase from Cu(111) through Ag(111) to Au(111). 相似文献
156.
Afanasiev S Aidala C Ajitanand NN Akiba Y Alexander J Al-Jamel A Aoki K Aphecetche L Armendariz R Aronson SH Averbeck R Awes TC Azmoun B Babintsev V Baldisseri A Barish KN Barnes PD Bassalleck B Bathe S Batsouli S Baublis V Bauer F Bazilevsky A Belikov S Bennett R Berdnikov Y Bjorndal MT Boissevain JG Borel H Boyle K Brooks ML Brown DS Bucher D Buesching H Bumazhnov V Bunce G Burward-Hoy JM Butsyk S Campbell S Chai JS Chernichenko S Chiba J Chi CY Chiu M Choi IJ Chujo T Chung P Cianciolo V 《Physical review letters》2008,100(23):232301
A three-dimensional correlation function obtained from midrapidity, low p(T), pion pairs in central Au+Au collisions at sqrt[s(NN)]=200 GeV is studied. The extracted model-independent source function indicates a long range tail in the directions of the pion pair transverse momentum (out) and the beam (long). A proper breakup time tau(0) ~ 9 fm/c and a mean proper emission duration Delta tau ~ 2 fm/c, leading to sizable emission time differences ({|Delta t(LCM)|} approximately 12 fm/c), are required to allow models to be successfully matched to these tails. The model comparisons also suggest an outside-in "burning" of the emission source reminiscent of many hydrodynamical models. 相似文献
157.
Local and semilocal density functional approximations for the exchange-correlation energy fail badly in the zero-thickness limit of a quasi-two-dimensional electron gas, where the density variation is rapid almost everywhere. Here we show that a fully nonlocal fifth-rung functional, the inhomogeneous Singwi-Tosi-Land-Sj?lander (STLS) approach, which employs both occupied and unoccupied Kohn-Sham orbitals, recovers the true two-dimensional STLS limit and appears to be remarkably accurate for any thickness of the slab (and thus for the dimensional crossover). We also show that this good behavior is only partly due to the use of the full exact exchange energy. 相似文献
158.
Constantin LA Pitarke JM Dobson JF Garcia-Lekue A Perdew JP 《Physical review letters》2008,100(3):036401
We resolve the long-standing controversy over the metal surface energy: Density-functional methods that require uniform-electron-gas input agree with each other, but not with high-level correlated calculations such as Fermi hypernetted chain and diffusion Monte Carlo calculations that predict the uniform-gas correlation energy. Here we apply the inhomogeneous Singwi-Tosi-Land-Sj?lander method, and find that the density functionals are indeed reliable (because the surface energy is bulklike). Our work also vindicates the use of uniform-gas-based nonlocal kernels in time-dependent density-functional theory. 相似文献
159.
Doumpos Michalis Papastamos Dimitrios Andritsos Dimitrios Zopounidis Constantin 《Annals of Operations Research》2021,306(1-2):415-433
Annals of Operations Research - Automated valuation models are widely used in real estate to provide estimates for property prices. Such models are typically developed through regression... 相似文献