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151.
利用车载被动DOAS测量系统,对某钢铁企业进行分装置绕行观测。采用了计算参与拟合截面相关性的方法,确定痕量气体最优反演波段,获取观测路径上的垂直柱浓度后,结合测量时间内的车速以及风速风向信息,计算得出区域内SO2及NO2排放净通量。实验得出某钢铁企业厂区内轧钢冶炼区域SO2与NO2排放净通量均值分别为149kg/h和372kg/h;焦化区域SO2与NO2排放净通量均值分别为260kg/h和286kg/h;电厂区域SO2与NO2排放净通量均值为21kg/h和26kg/h;石灰烧培区域SO2与NO2排放净通量均值为64kg/h和79kg/h;烧结区域SO2与NO2排放净通量均值为34kg/h和99kg/h。 相似文献
152.
A convenient method named wet coordination is used to prepare the sample or carbon-coated Li3V2(PO4)3 in the furnace with a flowing argon atmosphere at 600 °C for 1 h. The sample is characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and energy dispersive analysis of X-rays (EDAX). Galvanostatic charge–discharge between 3.3 and 4.3 V (vs. Li/Li+) shows that the sample exhibits a high discharge capacity of 128 mAh g?1 with a good reversible performance under a current density of 95 mA g?1. It suggests that carbon-coated Li3V2(PO4)3 with good electrochemical performance can be obtained via this method, which is suitable for large-scale production. 相似文献
153.
Highly ordered anodic TiO2 nanotube arrays and their stabilities as photo(electro)catalysts 总被引:1,自引:0,他引:1
Lingjie LiZhuqing Zhou Jinglei Lei Jianxin HeShengtao Zhang Fusheng Pan 《Applied Surface Science》2012,258(8):3647-3651
Highly ordered TiO2 nanotube arrays with an average diameter of 230 nm, a wall thickness of 30 nm and a length of 1.8 μm were fabricated within a large domain by electrochemically anodizing of a titanium foil in a mixed solution of glycerol and NH4F aqueous electrolyte. The TiO2 nanotubes exhibit an anatase structure after annealing at 450 °C in air for 3 h. The direct photolysis (DP), photocatalytic (PC), electrocatalytic (EC) and photoelectrocatalytic (PEC) activities of the TiO2 nanotube arrays were investigated using methyl orange (MO) as the model pollutant. The degradation of MO in PC process is faster than that in DP process, which confirms the photocatalysis of TiO2 nanotube arrays. The degradation rate in PEC process is much higher than those in EC and PC processes, which demonstrates the synergetic effect between PC and EC processes. The synergetic factor is 4.1, which suggests that the synergetic effect is strong. Moreover, the stabilities of morphology, structure and photo(electro)catalytic degradation performance of the TiO2 nanotube arrays were studied in order to evaluate their applicability as photo(electro)catalysts. The photo(electro)catalytic experiments bring neither morphological nor structural modifications to the nanotube arrays. The photo(electro)catalytic degradation rates of the TiO2 nanotube arrays maintain stable in 10 cycles, which indicates that the TiO2 nanotube arrays are appropriate to be applied as photo(electro)catalysts. 相似文献
154.
Multiferroic BiFeO3 nanoparticles and ceramics have been successfully prepared by sol–gel method and following high-pressure synthesis. The denser samples, good crystallization and crystal structure deformation have been obtained via high-pressure synthesis proved by XRD, SEM and Raman spectra. The enhanced magnetization of high-pressure samples attributes to crystal structure deformation; moreover, the enhanced dielectric loss of high-pressure samples results from good crystallization. The better microwave absorption properties can be obtained by high-pressure synthesis, and the minimum reflection loss elevates from ?13 dB at 12.4 GHz to ?17 dB at 11.2 GHz. It means that the high-pressure synthesis can effectively improve microwave absorption properties of multiferroic materials. 相似文献
155.
针对目前普遍采用的DSLAM设备。提出了一种IP接入模块的设计方案和IP over ATM解决方案,实现了基于ATM架构的IP—DSLAM技术,既发挥了ATM的综合业务接入能力,又使得运营商能够利用现有的ATM设备开展IP业务。 相似文献
156.
In this paper, a new multilevel correction scheme is proposed to solve Stokes eigenvalue problems by the finite element method. This new scheme contains a series of correction steps, and the accuracy of eigenpair approximation can be improved after each step. In each correction step, we only need to solve a Stokes problem on the corresponding fine finite element space and a Stokes eigenvalue problem on the coarsest finite element space. This correction scheme can improve the efficiency of solving Stokes eigenvalue problems by the finite element method. As applications of this multilevel correction method, a multigrid method and an adaptive finite element technique are introduced for Stokes eigenvalue problems. Some numerical results are given to validate our schemes. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
157.
Controllable Preparation of Hierarchical ZnO Nanocages and its Oxygen Vacancy through the Nanoscale Kirkendall Process
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Haosen Fan Jiaxin Zheng Jiangtao Hu Yantao Su Ning Zhao Jian Xu Fusheng Liu Feng Pan 《Particle & Particle Systems Characterization》2015,32(7):771-778
The synthesis of ZnO with tailorable shapes and point defects is important for its potential applications. Here, a facile approach is demonstrated to prepare ZnO nanocages with controllable porous shell structures though sintering a Zn‐based cyanide‐bridged coordination polymer under different temperatures. The transformation of ZnCP microspheres into ZnO nanocages is based on two types of nanoscale Kirkendall effect, which are related to low temperature solid–solid interfacial oxidation and high temperature solid–gas interfacial reaction, respectively. At low temperature (around 300 °C) and before the ZnCP decomposition, the novel “hierarchical ZnO bigger nanocages embedded with smaller nanocages with 10 nm nanocrystals” can be generated. By contrast, when coming to the total decomposition of ZnCP at 800 °C, ZnO nanocages with significantly increased sizes and large cavities are generated, and large amounts of oxygen vacancies (VO) are created at the same time, leading to the dramatic increased luminescence intensities of the UV peak due to VO at 540 nm. Thus, the luminescence intensities versus defect concentration in the prepared ZnO nanocages can also be controlled by tuning the sintering temperatures. 相似文献
158.
舰船噪声调制包络谱是水下目标识别的重要特征。本文提出了一种基于小波包分析和ZFFT的高频噪声解调分析(DEMON)方法,对多子带包络谱进行融合,得到了线谱特征明显的DEMON谱;利用倍频算法,对DEMON谱进行了轴频提取。舰船实测数据证明该分析方法的可行性和有效性。 相似文献
159.
本文介绍了反重力充填二维流形的颗粒显示、拍摄和数据测取方法。作为分析实例,给出了充型扩散角随内浇道扩张角变化的实验结果。 相似文献
160.