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81.
A new entropy function s+ is defined in terms of the existing entropy function s° and temperature as s+ = s° − R lnT to facilitate the analysis of isentropic processes of ideal gases with variable specific heats. The function s+ also makes it possible to calculate the entropy changes of ideal gases during processes when volume information is available instead of pressure information and the variation of specific heats with temperature is to be accounted for. The introduction of the function s+ eliminates the need to use the dimensionless isentropic functions relative pressure Pr and relative specific volume vr of ideal gases and to tabulate their values. The Pr and vr data are often confused with pressure and specific volume, with an adverse effect on the study of the second law of thermodynamics. The new s+ function nicely complements the existing s° function in entropy change calculations: the former is conveniently used when volume information is given while the latter is used when pressure information is available. Therefore, the introduction of the new entropy function s+ is expected to make a significant contribution to the thermodynamics education and research by streamlining entropy analysis of ideal gases. 相似文献
82.
M. Naim Yunus 《The Journal of the Operational Research Society》1989,40(12):1153-1155
An exact expression for the transient expectation of traffic overflowing from an Erlang loss system with stationary offered traffic is presented. Its derivation is obtained by using an exact expression for the transient blocking probability. This exact expectation could be useful in approximating the expectation of real-life overflow traffic. 相似文献
83.
Using the most recent differential cross section data for ep quasi-elastic scattering, the charged pion formation and its form factor Fπ is calculated in the energy range of 2.4 ~ 4 GeV at Q2 = 0.6 ~ 1.6 (GeV/c)2. The functional dependence of the charged pion form factor to the separated cross section σL is investigated and compared to the previously determined result. 相似文献
84.
Behzat Altural Yunus Akcamur Emin Saripinar Ismail Yildirim Gert Kollenz 《Monatshefte für Chemie / Chemical Monthly》1989,120(11):1015-1020
Summary 4-Benzoyl-5-phenylfuran-2,3-dione (1) and the semicarbazones2, ureas and thioureas6, respectively, combine with loss of water and carbondioxide yielding the 1H-pyrimidine derivatives3 and7, respectively, in moderate yields (30–75%). Hydrolysis of3 b leads to the 1-amino-pyrimidine-2-one4.Cordially dedicated to o. Univ.-Prof. Dr. Hans Junek on the occasion of his 60th birthday 相似文献
85.
86.
Maria Maares M. Menaf Ayhan Kai. B. Yu A. Ozgur Yazaydin Kevser Harmandar Hajo Haase Jens Beckmann Yunus Zorlu Gündoğ Yücesan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(48):11214-11217
A new family of porous metal–organic frameworks (MOFs), namely alkali phosphonate MOFs, is reported. [Na2Cu(H4TPPA)] ⋅ (NH2(CH3)2)2 ( GTUB-1 ) was synthesized using the tetratopic 5,10,15,20-tetrakis[p-phenylphosphonic acid] porphyrin ( H8-TPPA ) linker with planar X-shaped geometrical core. GTUB-1 is composed of rectangular void channels with BET surface area of 697 m2 g−1. GTUB-1 exhibits exceptional thermal stability. The toxicity analysis of the ( H8-TPPA ) linker indicates that it is well tolerated by an intestinal cell line, suggesting its suitability for creating phosphonate MOFs for biological applications. 相似文献
87.
Tunable N‐doped carbon nanospheres from sucrose as carbon source and Tris(2‐aminoethyl)amine (TAEA) as nitrogen source by a simple and easily reproducible method were prepared. It was demonstrated that the tunable N‐doping of carbon spheres could be realized by altering the ratio of TAEA in the raw materials. The content of doped nitrogen, surface area, pore volume and pore size of carbon nanospheres were increased with the increasing of TAEA amount in the hydrothermal process. Prepared N‐doped carbon nanospheres act as solid ligand for anchoring of Ag NPs which generated via chemical reduction of Ag ions. Benzylic alcohols and aldehydes were converted into the aryl nitriles by using Ag/N‐CS‐1 nanospheres as the catalyst and O2 as the oxidant, efficiently. This catalyst was stable and could use for 6 successful runs. 相似文献
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We introduce and study a mathematical model for temperature-modulated bioluminescence tomography (TBT). The model is capable of self-adjusting values of experimental parameters that are used in the formulation. Major theoretical results of this article include: Solution existence of the model, convergence of numerical solutions, an iterative scheme based on linearization, studies of the solution limiting behaviours when normalized total energy function and/or some or all the energy percentages in individual spectral bands are known exactly. Several numerical examples are included to illustrate the improvement of the accuracy of the reconstructed bioluminescent source distribution due to the employment of measurements from multiple temperature distributions. 相似文献