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排序方式: 共有166条查询结果,搜索用时 15 毫秒
161.
Genxiang Luo Qingdao Wang Haoping Wang 《Journal of Dispersion Science and Technology》2013,34(2):257-260
Based on extended Langmuir's method on the dressed micelles, approximate expressions for the calculation of interfacial tension and electrostatic free energy of spherical ionic micelles with high surface potentials have been presented. These expressions are derived from nonlinear Poisson‐Boltzmann equation. The present formulae for the calculation of interfacial tension and electrostatic free energy of spherical ionic micelles are in quite good agreement with Hayter's results. 相似文献
162.
Shutao Wang Changhua An Jie He Zongxian Wang State Key Laboratory of Heavy Oil Processing College of Chemistry Chemical Engineering China University of Petroleum Qingdao Sh ong China 《天然气化学杂志》2011,(4):408-412
Oil-soluble MoS2 nanoparticles with narrow size distribution have been synthesized by a facile composite-surfactants-aided-solvothermal process.The as-prepared nanoparticles can be directly used as hydrogenation nanocatalysts or as precursors to achieve efficient supported nanocatalysts.The surfaces of these nanoparticles are proposed to be encapsulated within a layer of organic modifiers,which are responsible for the enhancement of their solubility in organic solvents.The activated-carbon supported MoS2 nanocatalysts exhibit higher activity than the unsupported ones towards hydrogenation reactions of naphthalene,owing to the synergistic effects between nanoparticles and supports.The advantages of the present nanocatalysts,such as removal of conventional presulfiding requirements and reduction of nanoparticle aggregations,make them become promising applications in related petroleum chemical industry. 相似文献
163.
Hailiang Yin Tongna Zhou Yunqi Liu Yongming Chai Chenguang Liu State Key Laboratory of Heavy Oil Processing Key Laboratory of Catalysis CNPC China University of Petroleum Qingdao Sh ong China 《天然气化学杂志》2011,(4):441-448
Two mixed-matrix NiMo/Al2O3 catalysts containing nano-and micro-sized zeolite Y have been prepared to explore the size effect of zeolite Y particle on the hydrodesulfurization(HDS)and hydrodenitrogenation(HDN)activities of fluid catalytic cracking(FCC)diesel.They were characterized by SEM,BET,XRD,H2-TPR,NH3-TPD and HRTEM.The results show that the catalyst containing nano-sized zeolite Y possesses larger average pore diameter,higher pore volume,weaker and lesser acid sites,more easily reducible metal phases,shorter MoS2 slabs and more slab layers than the catalyst containing micro-sized zeolite Y.The catalysts were also evaluated with a high-pressure fixed-bed reactor using real FCC diesel as feed.The results display that the catalyst containing nano-sized zeolite Y bears higher HDS and HDN activities and exhibits higher relative rate constant for the removal of total sulfur or nitrogen than the one containing micro-sized zeolite. 相似文献
164.
Triangular systems play a fundamental role in matrix computations. It has become commonplace that triangular systems are solved to be more accurate even if they are ill-conditioned. In this paper, we define structured condition number and give structured (forward) perturbation bound. In addition, we derive the representation of optimal structured backward perturbation bound. 相似文献
165.
For symmetric tensors,computing generalized eigenvalues is equivalent to a homogenous polynomial optimization over the unit sphere.In this paper,we present an adaptive trustregion method for generalized eigenvalues of symmetric tensors.One of the features is that the trust-region radius is automatically updated by the adaptive technique to improve the algorithm performance.The other one is that a projection scheme is used to ensure the feasibility of all iteratives.Global convergence and local quadratic convergence of our algorithm are established,respectively.The preliminary numerical results show the efficiency of the proposed algorithm. 相似文献
166.
Jianghua Fang Xiaoyang Zhu Wendi Luo Jianxun Shi Lejia Wang Bin Tu Qingdao Zeng Xunwen Xiao 《中国化学快报》2022,33(2):1100-1104
The self-assembly characteristics of tetrathiafulvalene(TTF) derivatives molecules 1–3 at the 1-phenyloctane/HOPG(HOPG = highly oriented pyrolytic graphite) interface had been carefully studied by scanning tunneling microscopy(STM) method. The number of F atoms on the phenyl group had significantly affected the self-assembly structures. High-resolution STM images make clear the different assembly structures between the molecules 1–3, which attribute to the different F atom numbers and pyridine g... 相似文献