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Hong Guo Yapeng Wang Wei Wang Lixiang Liu Yuanyuan Guo Xiangjun Yang Shixiong Wang 《Particle & Particle Systems Characterization》2014,31(3):374-381
Hollow NiO–carbon hybrid nanoparticle aggregates are fabricated through an environmental template‐free solvothermal alcoholysis route. Controlled hollow structure is achieved by adjusting the ratio of ethylene glycol to water and reaction time of solvothermal alcoholysis. Amorphous carbon can be loaded on the NiO nanoparticles uniformly in the solvothermal alcoholysis process, and the subsequent calcination results in the formation of hollow NiO–C hybrid nanoparticle aggregates. As anode materials for lithium‐ion batteries, it exhibits a stable reversible capacity of 622 mAh g?1, and capacity retention keeps over 90.7% after 100 cycles at constant current density of 200 mA g?1. The NiO–C electrode also exhibits good rate capabilities. The unique hollow structures can shorten the length of Li‐ion diffusion and offer a sufficient void space, which sufficiently alleviates the mechanical stress caused by volume change. The hybrid carbon in the particles renders the electrode having a good electronic conductivity. Here, the hollow NiO‐C hybrid electrode exhibits excellent electrochemical performance. 相似文献
64.
Zuning Zhang Zhen Liu Yong Jiang Huachun Zhu Te Ji Jie Wang Min Chen Weiwei Peng Lihua Wang Xiangjun Wei 《X射线光谱测定》2022,51(4):394-402
Advanced synchrotron radiation light is a powerful tool for archaeometry research. However, its applications to precious cultural relics, especially for color painting, have been hindered to some degree due to potential X-ray radiation damage. Compared to inorganic mineral pigments, organic binders in the painting are easier to be damaged by synchrotron radiation X-ray beam. The radiation damage effect of two typical painting samples, pure rabbit skin glue and the mixed sample of rabbit skin glue and zinc white, has been investigated by in situ time-resolved ED-XAS and IR combined techniques. The results show that the radiation damage effect of pure rabbit skin glue is more serious at low X-ray energy (7775 eV). The radiation damage effect of the mixed sample increases significantly due to more X-ray absorption by inorganic pigments. Furthermore, the radiation damage is more serious at the energy near Zn K-edge and is somewhat slight at higher energy (13,054 eV). These damages are more obvious from the point of view of protein secondary structures. The irradiation damage effects increase more rapidly at the beginning and are not linear with the irradiating time. The results indicate that synchrotron radiation damage can be reduced effectively by using X-ray energy far away from the X-ray absorption edge of the major element in the pigments during XRF, XRD and CT experiments, or by using time-resolved techniques such as QXAFS and ED-XAS during XAFS experiments. 相似文献
65.
Zongying Cai Jie Song Junshou Li Fang Zhao Xiaohe Luo Xiangjun Tang 《Journal of Sol-Gel Science and Technology》2012,61(1):49-55
A facile and economic electrospinning approach has been developed for the synthesis of zinc titanate-rutile composite fibers
as a nanofibrous mat at the first time. The composite fibers with different morphologies were obtained by calcination of the
PVP/Ti(OC4H9)4–Zn(CH3COO)2 fibers. The reaction mechanism was characterized by thermogravimetry-differential thermal analysis (TG-DTA), X-ray diffractometer
(XRD), field emission scanning electron microscopy (FE-SEM) and Fourier transform infraction spectroscopy (FT-IR) spectra
techniques. According to the thermal analysis, the phase of ZnTiO3 occurred at 450 °C and it decomposed at 885 °C. FE-SEM micrographs indicated that the as-spun fibers were round and had a
rather uniform and smooth surface with the diameters in the range of 300–800 nm over its length. Its morphology is greatly
affected by the calcination temperatures. 相似文献
66.
Xiangjun Wu Hongtao Lu 《Communications in Nonlinear Science & Numerical Simulation》2012,17(11):4417-4429
In this paper, projective lag synchronization of the general complex dynamical networks with different nodes is investigated. Combining Barbalat’s lemma with adaptive control technique, the adaptive feedback controllers are constructed to achieve projective lag synchronization between the dynamical network with diverse nodes and arbitrary desired trajectory. The presented synchronization method can be applied to any complex networks. It is discovered that the update gains, the time delay, the network size and the network topology have influence on the synchronization effect. Furthermore, projective lag synchronization of the dynamical networks can still be efficiently realized in presence of noise and parameter perturbations. Corresponding numerical simulations are performed to validate the effectiveness and robustness of the proposed synchronization scheme. 相似文献
67.
The optimized geometries, frequencies, and total electronic energies of two all-metal dianionic clusters Ga42- , In42- are calculated at the B3LYP, B3PW91, and MP2 levels of theory. There are two stable structures for each Ga42- , In42- species. For Ga42- , In42- species the square isomers are the most stable. On the basis of these computed stable structures we focus on two magnetic properties: magnetic susceptibility anisotropy and nucleus-independent chemical shift (NICS) for the square planar Ga42- , In42- isomers, which are calculated with B3LYP and HF methods. The computed results of NICS show that the square planar Ga42- , In42- isomers possess strong aromaticity. The detailed molecular orbital analysis for the two isomers further reveals that the two square planar Ga42- , In42- isomers have multiple-fold aromaticity: one delocalized π MOs and two delocalized σ MOs, which play important role in explaining the special stability of these all-metal square clusters. 相似文献
68.
陕甘宁革命老区是黄土高原和黄河中上游的重点生态治理区,作为重要的生态屏障区,其生态治理意义重大。以陕甘宁革命老区为研究区域,基于改进的生态系统服务价值(ecosystem service value,ESV)当量因子法,利用地理探测器及地理加权回归(geographically weighted regression,GWR)模型,分析1995—2018年各县ESV时空变化特征、影响因素及各主导因素作用强度的空间分异特征。结果表明:(1) 1995—2018年,陕甘宁革命老区ESV呈先下降后上升的特征,整体呈上升趋势,草地与林地对该区域ESV的贡献较大;(2) ESV空间等级转化呈现较显著的两极变化趋势,其中低级、高级ESV区域面积显著扩张,较高级ESV区域面积明显缩减;(3)地被覆盖度、人口密度、垦殖系数是ESV空间分异的主导因素,平均空间解释力超过0.378 0,自然、社会、经济因素间的交互协同增强了其对陕甘宁革命老区ESV的影响程度;(4)各主导因素对ESV的影响程度表现出空间异质性,其中地被覆盖度及垦殖系数的影响程度由东向西递减,人均GDP和人口密度的影响程度则由西向东递减。 相似文献
69.
Fluid Dynamics - A high-order discontinuous Galerkin method is employed to study the evolution of the flow structure in the gap and near wake of two tandem cylinders in the alternating in the gap... 相似文献
70.
Zhou Wang Chunping Zhang Guanghua Fu Xiangjun Yan Hemu Wang Guangying Zhang 《Chinese Journal of Lasers》1992,1(3):229-234
Forces exerted on a small transparent dielectric sphere in a Gaussian beam is an-alyzed.The stable position of the sphere in the Gaussian beam was calculated.The effects ofthe sphere size,the beam radius etc.on the exerted forces,on the equilibrium positions aswell as on other parameters of the sphere are discussed. 相似文献