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991.
Dr. Karl Kaupmees Robert Järviste Prof. Dr. Ivo Leito 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(48):17445-17449
The basicity scale of very weak bases has been set up in 1,2‐dichloroethane to give, for the first time, reliable quantitative insights into the basic properties of weak bases in a low‐polarity solvent. The scale contains 30 compounds, including anilines; phosphanes, and carbonyl bases, such as esters and amides, linked by 53 relative basicity measurements. The scale spans more than 12 pKip units, expanding to as low pKip values as possible with our current experimental methodology. 相似文献
992.
J. Ollig M. Morbach G. Hägele E. Breuer K. Killner 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Various methods of NMR- and PC-controlled titrations were developed in our laboratories. In addition to the by now well-investigated 31P- we applied 13C-, 1H-, 19F- and 113Cd-NMR controlled titrations. Here we report about the methodical progress and results obtained from acylphophonic acids and corresponding hydroxyimino derivatives - as shown below - which gained interests as potentially anti-viral agents: 相似文献
993.
I. Spǎnulescu I. Dima Mohamed Ismail Abd El-Ati N. Bǎlţǎţeanu Talal Khalass 《辐射效应与固体损伤》2013,168(3-4):299-303
The influence of 8 MeV electrons on the crystalline structure of HgTe and Hg1-xCdxTe thin films was studied. HgTe and Hg1-xCdxTe layers were obtained by thermal evaporation and condensation in vacuum on optically flat silica glass substrates heated at different temperatures. One finds that the results of irradiation of HgTe and Hg1-xCdxTe thin films with 8 MeV electrons depend on the preparation conditions of the samples, and therefore on the level of perfection of the crystalline structure and the quantity of nonstoichiometric atoms. 相似文献
994.
R. Furtwängler A.-C. Hauschild J. Hübel H. Rakicioglou B. Bödeker S. Maddula A. Simon J. I. Baumbach 《International Journal for Ion Mobility Spectrometry》2014,17(1):19-23
Children undergoing systemic chemotherapy often suffer from severe immunosuppression usually associated to severe neutropenia (neutrophils <?0.5 x 109/l). Clinical courses during those periods range from asymptomatic to septic general conditions. Development of septic symptoms can be very fast and life-threatening. Swift detection of risk factors in those patients is therefore needed. So far no early, rapid and reliable marker or tool exists. Ion-Mobility-Spectrometry coupled with a Multi-Capillary-Column (IMS-MCC) can analyze more than 600 volatile components from exhaled air within a few minutes and hence is a potential, rapid detection-tool. As a proof of concept we measured the exhaled breath of 11 patients with neutropenia and 10 healthy controls ranging from 3 to 18 years of age at the time of measurement. Ten milliliters breath samples were taken at the outpatient clinic and analyzed with an onsite IMS-MCC (BreathDiscovery, B&S Analytik, Dortmund, Germany). Dead-space-volume was adapted to two groups (small 250 ml, large 500 ml). Interestingly 59 differing peaks were measured. Eleven were significantly different (p?≤?0.05), three of which highly significant (p?≤?0.01) in Mann-Whitney-Rank-Sum-testing. The corresponding analytes used in the decision tree are 2-Propanol, D-Limonene and Acetone. The analytes with the lowest rank sum identified are 2-Hexanone, Iso-Propylamine and 1-Butanol. Eventually we were able to show a three-step-decision-tree, which discerns the 21 samples except one from each group. Sensitivity was 90 % and specificity was 91 %. Naturally these findings need further confirmation within a bigger population. Our pilot-study proves that Ion-Mobility-Spectrometry coupled with a Multi-Capillary-Column is a feasible rapid diagnostic tool in the setting of a pediatric oncology out-patient clinic for patients 3 years and older. Our first results furthermore encourage additional analysis as to whether patients at risk for septic events during immunosuppression can be diagnosed in advance by rapidly assessing risk factors such as Neutropenia in exhaled breath. 相似文献
995.
996.
Pál Burai 《Journal of Optimization Theory and Applications》2014,162(1):34-46
The main goal of this paper is to prove some new results and extend some earlier ones about functions, which possess the so-called local–global minimum property. In the last section, we show an application of these in the theory of calculus of variations. 相似文献
997.
998.
İbrahim Muter Ş. İlker BirbilKerem Bülbül Güvenç Şahin 《European Journal of Operational Research》2012
In their paper, Avella et al. (2006) investigate a time-constrained routing problem. The core of the proposed solution approach is a large-scale linear program that grows both row- and column-wise when new variables are introduced. Thus, a column-and-row generation algorithm is proposed to solve this linear program optimally, and an optimality condition is presented to terminate the column-and-row generation algorithm. We demonstrate by using Lagrangian duality that this optimality condition is incorrect and may lead to a suboptimal solution at termination. 相似文献
999.
Dr. Quentin Bonnin Tereza Edlová Dr. E. Daiann Sosa Carrizo Prof. Dr. Paul Fleurat-Lessard Dr. Stéphane Brandès Dr. Hélène Cattey Dr. Philippe Richard Prof. Dr. Pierre Le Gendre Dr. Adrien T. Normand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(72):18175-18187
Cationic amidotitanocene complexes [Cp2Ti(NPhAr)][B(C6F5)4] (Cp=η5-C5H5; Ar=phenyl ( 1 a ), p-tolyl ( 1 b ), p-anisyl ( 1 c )) were isolated. The bonding situation was studied by DFT (Density Functional Theory) using EDA-NOCV (Energy Decomposition Analysis with Natural Orbitals for Chemical Valence). The polar Ti−N bond in 1 a–c features an unusual inversion of σ and π bond strengths responsible for the balance between stability and reactivity in these coordinatively unsaturated species. In solution, 1 a–c undergo photolytic Ti−N cleavage to release Ti(III) species and aminyl radicals ⋅ NPhAr. Reaction of 1 b with H3BNHMe2 results in fast homolytic Ti−N cleavage to give [Cp2Ti(H3BNHMe2)][B(C6F5)4] ( 3 ). 1 a–c are highly active precatalysts in olefin hydrogenation and silanes/amines cross-dehydrogenative coupling, whilst 3 efficiently catalyzes amine-borane dehydrogenation. The mechanism of olefin hydrogenation was studied by DFT and the cooperative H2 activation key step was disclosed using the Activation Strain Model (ASM). 相似文献
1000.
The Dempster-Shafer theory of belief functions has proved to be a powerful formalism for uncertain reasoning. However, belief
functions on a finite frame of discernment Ω are usually defined in the power set 2Ω, resulting in exponential complexity of the operations involved in this framework, such as combination rules. When Ω is linearly
ordered, a usual trick is to work only with intervals, which drastically reduces the complexity of calculations. In this paper,
we show that this trick can be extrapolated to frames endowed with an arbitrary lattice structure, not necessarily a linear
order. This principle makes it possible to apply the Dempster-Shafer framework to very large frames such as the power set,
the set of partitions, or the set of preorders of a finite set. Applications to multi-label classification, ensemble clustering
and preference aggregation are demonstrated. 相似文献