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141.
Arif Uzma Nawaz M. Alharbi Sayer Obaid Saleem S. 《Journal of Thermal Analysis and Calorimetry》2021,144(3):729-737
Journal of Thermal Analysis and Calorimetry - This article explores the role of hybrid nano-particles in enhancing the thermal performance of Sutterby fluid over a two-dimensional body of variable... 相似文献
142.
Syed Farooq Adil Mohamed E. Assal Mohammed Rafi Shaik Mufsir Kuniyil Azhar Hashmi Mujeeb Khan Aslam Khan Muhammad Nawaz Tahir Abdulrahman Al-Warthan Mohammed Rafiq H. Siddiqui 《应用有机金属化学》2020,34(8):e5718
Graphene–metal nanocomposites have been found to remarkably enhance the catalytic performance of metal nanoparticle-based catalysts. In continuation of our previous report, in which highly reduced graphene oxide (HRG)-based nanocomposites were synthesized and evaluated, we present nanocomposites of graphene oxide (GRO) and ZnO nanoparticle-doped MnCO3 ([ZnO–MnCO3/(1%)GRO]) synthesized via a facile, straightforward co-precipitation technique. Interestingly, it was noticed that the incorporation of GRO in the catalytic system could noticeably improve the catalytic efficiency compared to a catalyst (ZnO–MnCO3) without GRO, for aerial oxidation of benzyl alcohol (BzOH) employing O2 as a nature-friendly oxidant under base-free conditions. The impacts of various reaction factors were thoroughly explored to optimize reaction conditions using oxidation of BzOH to benzaldehyde (BzH) as a model substrate. The catalysts were characterized using X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, Energy dispersive X-ray spectroscopy (EDX), Brunauer-Emmett-Teller (BET), and Raman spectroscopy. The (1%)ZnO–MnCO3/(1%)GRO exhibited significant specific activity (67 mmol.g−1.hr−1) with full convversion of BzOH and >99% BzH selectivity within just 6 min. The catalytic efficiency of the (1%)ZnO–MnCO3/(1%)GRO nanocomposite was significantly better than the (1%)ZnO–MnCO3/(1%)HRG and (1%)ZnO–MnCO3 catalysts, presumably due to the existence of oxygen-possessing groups on the GRO surface and as well as a very high surface area that could have been instrumental in uniformly dispersing the active sites of the catalyst, i.e., ZnO–MnCO3. Under optimum circumstances, various kinds of alcohols were selectively transformed to respective carbonyls with full convertibility over the (1%)ZnO–MnCO3/(1%)GRO catalyst. Furthermore, the highly effective (1%)ZnO–MnCO3/(1%)GRO catalyst could be successfully reused and recycled over five consecutive runs with a marginal reduction in its performance and selectivity. 相似文献
143.
Classification and rule induction are two important tasks to extract knowledge from data. In rule induction, the representation of knowledge is defined as IF-THEN rules which are easily understandable and applicable by problem-domain experts. In this paper, a new chromosome representation and solution technique based on Multi-Expression Programming (MEP) which is named as MEPAR-miner (Multi-Expression Programming for Association Rule Mining) for rule induction is proposed. Multi-Expression Programming (MEP) is a relatively new technique in evolutionary programming that is first introduced in 2002 by Oltean and Dumitrescu. MEP uses linear chromosome structure. In MEP, multiple logical expressions which have different sizes are used to represent different logical rules. MEP expressions can be encoded and implemented in a flexible and efficient manner. MEP is generally applied to prediction problems; in this paper a new algorithm is presented which enables MEP to discover classification rules. The performance of the developed algorithm is tested on nine publicly available binary and n-ary classification data sets. Extensive experiments are performed to demonstrate that MEPAR-miner can discover effective classification rules that are as good as (or better than) the ones obtained by the traditional rule induction methods. It is also shown that effective gene encoding structure directly improves the predictive accuracy of logical IF-THEN rules. 相似文献
144.
It is proved that the set of all semi pandiagonal 4 × 4-squares precisely consists of 3456 squares belonging to three orbits under the faithful action of a group of order 1152 which is a semi direct product of symmetric groups. 相似文献
145.
M. Saleem N. Amin S. Hussain M. Rafiq S. Mahmood M. A. Baig 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(2):277-283
New measurements of photoionization cross-sections of the lithium isotopes
are reported employing a Time of Flight (TOF) mass spectrometer in
conjunction with an atomic beam apparatus. Using a two-step selective
photoionization and saturation technique, we have simultaneously measured
the photoionization cross-section of the 2p excited state of both the
isotopes Li6 and Li7 as 15±2.5 Mb and 18 ±2.5 Mb
where as the corresponding number densities have been determined as
N0≈5.3×1010 atoms/cm3 and
N0≈6.2×1011 atoms/cm3 respectively. 相似文献
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149.
Davut Avcı Sümeyye Altürk Fatih Sönmez Ömer Tamer Adil Başoğlu Yusuf Atalay Belma Zengin Kurt Necmi Dege 《Tetrahedron》2018,74(50):7198-7208
Novel complexes of 6?methylpyridine?2?carboxylic acid and thiocyanate {[Cu(NCS)(6-mpa)2], (1); [Cd(NCS)(6-mpa)]n, (2); [Cr(NCS)(6-mpa)2·H2O], (3)} were synthesized, and their structures were characterized by XRD analysis, FT–IR and UV–Vis spectroscopic techniques. The inhibitory activities of the synthesized complexes (1–3) on α-glucosidase were determined by using genistein reference compound. Furthermore, the optimized geometry and vibrational harmonic frequencies for the complexes 1–3 were obtained by DFT/HSEh1PBE/6–311G(d,p)/LanL2DZ level. Electronic spectral properties were examined by using TD-DFT/HSEh1PBE/6–311G(d,p)/LanL2DZ level with CPCM model. Additionally, major contributions to the electronic transitions were determined via Swizard program. The refractive index, linear optical and non?nonlinear optical parameters of the complexes 1–3 were investigated at HSEh1PBE/6–311G(d,p) level. The docking studies of the complexes 1–3 to the binding site of the target protein (the template structure S. cerevisiae isomaltase are fulfilled. Lastly, natural bond orbital analysis was used to investigate inter- and intra-molecular bonding and interaction among bonds. 相似文献
150.
Adil A. Gobouri Naif A. Alshanbari Mosselhi A. M. Mohamed 《Phosphorus, sulfur, and silicon and the related elements》2020,195(3):211-217
AbstractEthylcarboxylate and acetyl selenoloquinoline derivatives were prepared in a one pot synthesis via reaction of sodium hydrogen selenide and 2-chloro-3-cyano-4-methylquinoline followed by reactions with ethyl chloroacetate and chloro acetone respectively which used as precursors to synthesize many of tetra and pentacyclic systems. A new series of pyrimido [4′,5′:4,5]selenolo[2,3-b]quinoline, thiazino[2’,3’:4,5]selenolo[2,3-b]quinoline, oxazino[2',3':4,5]selenolo[3,2-b]quinoline, pyrido[2′,3′:4,5]selenolo[2,3-b]quinoline, pyrido[2′,3′:4,5]selenolo[2,3-b]quinoline-2-substituted selenyl and selenolo[2′,3′:5,6]pyrido[2″,3″:4,5]selenolo[2,3-b]quinoline derivatives were prepared. Elemental analysis, IR, 1H NMR, 13C NMR and mass spectra confirmed the structures of the newly synthesized compounds. 相似文献