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991.
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Molecular dynamics simulation of effect of liquid layering around the nanoparticle on the enhanced thermal conductivity of nanofluids 总被引:1,自引:0,他引:1
The effect of the molecular layering at liquid–solid interface on the thermal conductivity of the nanofluid is investigated
by an equilibrium molecular dynamics simulation. By tracking the position of the nanoparticle and the liquid atoms around
the spherical nanoparticle, it was found that a thin layer of liquid is formed at the interface between the nanoparticle and
liquid; this thin layer will move with the Brownian motion of the nanoparticle. Through the analysis of the density distribution
of the liquid near the nanoparticle, it is found that more argon atoms are attracted to form the layer around the nanoparticle
when the diameter of the nanoparticle is larger, and therefore lead to the more significant enhancement of the thermal conductivity
of the nanofluid. 相似文献
995.
996.
Homotopic mapping solutions for generalized method of solitary wave complex Burgers equation
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A class of generalized complex Burgers equation is considered. First, a set of equations of the complex value functions are solved by using the homotopic mapping method. The approximate solution for the original generalized complex Burgers equation is obtained. This method can find the approximation of arbitrary order of precision simply and reliably. 相似文献
997.
Dongyan Zhou Yue Sun Zixian Bao Wenshuai Liu Mo Xian Rui Nian Fei Xu 《Macromolecular bioscience》2019,19(5)
Bacterial cellulose (BC) is a natural product with multiple properties, which has been utilized in tissue engineering. However, cell adhesion and proliferation are reported to be weaker on native BC, providing less support compared to other types of biomaterials, like collagen. To increase the biocompatibility and the medical performance of BC, in situ modification is used to add carboxymethyl group to BC. By partially changing the structure and physical properties of BC, carboxymethylation significantly increases cell affinity and viability, especially on the initial cell adhesion. Furthermore, in the in vivo implantation, the tissue reaction shows that carboxymethylation significantly increases the biocompatibility of BC, exhibiting better tissue condition and a lower inflammatory reaction which are proved through HE staining and immunohistochemistry. The data prove that in situ carboxymethylation is a simple and direct way of improving the performance of BC in medical applications. 相似文献
998.
Ki‐Hyun Cho Jaeyoung Heo Yun‐Mo Sung Prashant K. Jain 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(25):8498-8503
Cuprous selenide nanocrystals have hallmark attributes, especially tunable localized surface plasmon resonances (LSPRs) and super‐ionic behavior. These attributes of cuprous selenide are now integrated with a one‐dimensional morphology. Essentially, Cu2Se nanowires (NWs) of micrometer‐scale lengths and about 10 nm diameter are prepared. The NWs exhibit a super‐ionic phase that is stable at temperatures lower than in the bulk, owing to compressive lattice strain along the radial dimension of the NWs. The NWs can be switched between oxidized and reduced forms, which have contrasting phase transition and LSPR characteristics. This work thus makes available switchable, one‐dimensional waveguides and ion‐conducting channels. 相似文献
999.
Yingying Liu Yiran Mo Xiaodi Dong Lin Chen Ling Ye Xinying Li Zhigang Zhao Xuefeng Li 《Tetrahedron》2019,75(17):2466-2471
A highly enantioselective (84–97% ee) cascade Michael/acyl transfer reaction of α-nitroketones to a wide range of 2-hydroxychalcones was established in the presence of a bifunctional squaramide. Although aliphatic α-nitroketones were revealed to be a class of challenging substrates with unsatisfactory reactivity or enantioselectivity by previous reports, good isolated yields and excellent enantiopurities have been achieved via our catalytic protocol. γ-Nitroketones created by this new methodology were versatile building blocks possessing profound further synthetic utility. 相似文献
1000.
Heng Zeng Mo Xie Yong‐Liang Huang Yifang Zhao Xiao‐Jing Xie Jian‐Ping Bai Meng‐Yan Wan Rajamani Krishna Weigang Lu Dan Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(25):8603-8607
Porous materials that can undergo pore‐structure adjustment to better accommodate specific molecules are ideal for separation and purification. Here, we report a stable microporous metal‐organic framework, JNU‐1, featuring one‐dimensional diamond‐shaped channels with a high density of open metal sites arranged on the surface for the cooperative binding of acetylene. Together with its framework flexibility and appropriate pore geometry, JNU‐1 exhibits an induced‐fit behavior for acetylene. The specific binding sites and continuous framework adaptation upon increased acetylene pressure are validated by molecular modeling and in situ X‐ray diffraction study. This unique induced‐fit behavior endows JNU‐1 with an unprecedented increase in the acetylene binding affinity (adsorption enthalpy: up to 47.6 kJ mol?1 at ca. 2.0 mmol g?1 loading). 相似文献