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51.
Parham Dehghan Mina Noroozi Gity Mir Mohamad Sadeghi Mahbod Abrisham Arian Amirkiai Mahyar Panahi-Sarmad 《Journal of polymer science. Part A, Polymer chemistry》2020,58(21):3082-3094
The recent global pandemic and its tremendous effect on the price fluctuations of crude oil illustrates the side effects of petroleum dependency more evident than ever. Over the past decades, both academic and industrial communities spared endless efforts in order to replace petroleum-based materials with bio-derived resources. In the current study, a series of shape memory polymer composites (SMPC's) was synthesized from epoxidized vegetable oils, namely canola oil and castor oil fatty acids (COFA's) as a 100% bio-based polyol and isophorone diisocyanate (IPDI) as an isocyanate using a solvent/catalyst-free method in order to eventuate polyurethanes (PU's). Thereafter, graphene oxide (GO) nanoplatelets were synthesized and embedded in the neat PU in order to overcome the thermomechanical drawbacks of the neat matrix. The chemical structure of the synthesized components, as well as the dispersion and distribution levels of the nanoparticles, was characterized. In the following, thermal and mechanical properties as well as shape memory behavior of the specimens were comprehensively investigated. Likewise, the thermal conductivity was determined. This study proves that synthesized PU's based on vegetable oil polyols, including graphene nanoparticles, exhibit proper thermal and mechanical properties, which make them stand as a potential candidate to compete with traditional petroleum-based SMPC's. 相似文献
52.
Mwsleh Mwhmadi Mehdi Kamali Jamal Rashidiani Omid Rezai Kaveh Moradi Ashkan Faridi Khadijeh Eskandari 《Journal of Cluster Science》2014,25(6):1577-1587
NiO and CuO nanostructures were synthesized successfully via simple and fast microwave approach. Olive oil was chose as surfactant for stabilizing nanostructures. Different parameters such as microwave time and power and olive oil concentration were investigated on product size and morphology. The products were characterized with X-ray diffraction pattern, scanning electron microscopy, transmission electron microscopy and energy dispersive spectrometry analysis. 相似文献
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54.
Application of chromium‐doped fullerene as a carrier for thymine and uracil nucleotides: Comprehensive density functional theory calculations 下载免费PDF全文
Ali Shokuhi Rad Sadegh Mehdi Aghaei Elaheh Aali Majid Peyravi Mohsen Jahanshahi 《应用有机金属化学》2018,32(2)
The interactions of the nucleobases thymine (C5H6N2O2) and uracil (C4H4N2O2) with Cr‐doped C20 fullerene (C19Cr) are investigated by performing density functional theory calculations. The adsorption of these nucleobases on C19Cr leads to two distinct geometries (P1 and P2) differing in the orientation of the nucleobases. The interaction of the nucleobases with the C19Cr nanocluster is highly exothermic, revealing that they are chemically adsorbed on C19Cr. The results show that the binding energy of the thymine–C19Cr complex is slightly higher than that of the uracil–C19Cr complex. In addition, the P2 geometry is more stable compared to P1 due to the higher binding energy in the former configuration. However, based on the results of natural bond orbital and frontier molecular orbitals analyses, the C19Cr nanocage has higher reactivity with the nucleobases in P1 geometry in comparison with P2 due to the larger charge transfer and orbital hybridization in the former geometry. Moreover, the band gap of the C19Cr nanocage decreases after interaction with the nucleobases, and interestingly the impact is more pronounced for P1 geometry, confirming the higher sensitivity of C19Cr to the nucleobases in P1 geometry. Our findings reveal the promising potential of C19Cr as an organometallic carrier for nucleobases thymine and uracil. 相似文献
55.
In this work, a simple and green method is reported for the biosynthesis of Cu/bone nanocomposite using Cordyline fruticosa extract as a stabilizer and reductant. Animal bone was used as a natural support to prevent the accumulation of Cu nanoparticles. The catalytic activity of Cu/bone nanocomposite was assessed in the synthesis of 1‐substituted 1H‐1,2,3,4‐tetrazoles and reduction of various organic dyes, including 4‐nitrophenol (4‐NP), nigrosin (NS), congo red (CR) and methylene blue (MB). The best catalytic performance in the synthesis of 1‐substituted tetrazoles was achieved using 0.05 g of Cu/bone nanocomposite at 120°C. In addition, under optimal conditions, the absorption bands corresponding to 4‐NP, CR, NS and MB completely disappeared after about 6 min, 3 min, 50 s and 7 s, respectively. The biosynthesis protocol used in the preparation of Cu/bone nanocomposite offers a very attractive area for further research. 相似文献
56.
The synthesis, characterization, and evaluation of a Schiff base Cu (II) complex functionalized boehmite nanoparticles (Cu-complex-boehmite) as a new catalyst for oxidation of sulfides and thiols in the presence of hydrogen peroxide with complete selectivity and high conversion under solvent-free and mild reaction conditions were reported. Characterization of the catalyst was performed with various physicochemical methods. This effective catalyst was evaluated in terms of activity and reusability. It indicated high catalytic activity, good recoverability and reusability, and supplied the corresponding products in high yields and short reaction times. In addition, it shows notable advantages such as simplicity of operation, heterogeneous nature, easy work up, and it could be used at least eight times with no significant loss of its activity. 相似文献
57.
Mohammad Mehdi Khodaei Davood Kordestani 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2403-2405
Abstract Direct conversion of acylals to the corresponding bisulfites can be easily performed in the presence of bismuth (III) nitrate pentahydrate in ethanol at room temperature in good yields. 相似文献
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59.
Benvidi Ali Tezerjani Marzieh Dehghan Moshtaghiun Seyed Mohammad Mazloum-Ardakani Mohammad 《Mikrochimica acta》2016,183(5):1797-1804
Microchimica Acta - The authors describe an aptasensor for tetracycline (TET) based on the use of a glassy carbon electrode (GCE) modified with graphene oxide nanosheets. The latter were placed on... 相似文献
60.
In this study, the biologically active configurations composed of Thiazolidinedione–Uracil (TU) and Rhodanine–Uracil (RU) have been fully investigated from the energetic and structural points of view, employing B3LYP and M062X functionals in combination with the different basis sets. Dispersion corrections to the interaction energy using M062X–GD3 and double hybrid density functionals (B2PLYP–GD2, B2PLYP–GD3 and mPW2PLYP–GD2) are also taking into account. The basis set superposition error-corrected interaction energy for hydrogen bonded configurations ranges from ??5.27 to ??13.53 and ??5.25 to ??12.93 kcal/mol for TU and RU complexes respectively as calculated at M062X/6–311++G(df,pd) level. The charge transfer process within all of the TU and RU configurations were analyzed using Natural Bond Orbital (NBO) calculations. The nature of the interactions is analyzed with NBO and Atoms in Molecules (AIM) analysis at M062X/6–311++G(df,pd) and energy decomposition analysis at BP86–D3/TZ2P(ZORA)//M062X/6–311++G(df,pd) level of theory. The results confirm that the nature of the interactions is nearly electrostatic, with a contribution of about 51–56% of the total interaction energy. The orbital interactions (ΔEorb) for the considered TU and RU complexes have a contribution of about 24–38% of the total interaction energy. Based on the AIM and NBO results, the interactions were defined as electrostatic H-bonds with partially covalent character. In addition, correlation between interaction energies and vibrational frequency changes was investigated. 相似文献