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91.
Based on an existing three-dimensional (3-D) channel model developed by WINNER II/+, we propose an extended 3-D channel model, which takes the vertical velocity component and polarized array structure into account. The distributions of several channel parameters are verified through simulation. Furthermore, initial system-level simulation results for a 3D-MIMO transmission scheme are presented in this paper.  相似文献   
92.
Supply contract helps in coordinating the supply of quantities from different suppliers in order to meet the demand for a product. In this paper, supply contract models are developed by considering an assembly system operated under a centralized and a decentralized control modes. The centralized control mode considers a single decision maker and offers a global optimal solution. However, the decentralized control mode considers each player in the contract as a decision maker and offers local optimal solutions based on the production and cost characteristics of each player. Such local optimal solutions are adjusted through coordinating parameters to obtain global optimal solutions. If a contract developed for a decentralized control mode achieves the global optimal solution, then the supply chain (or channel) is said to be coordinated.  相似文献   
93.
Recent studies have focused on the structural features of DNA-lipid assemblies. In this paper, we take methyl green (MG) as a probe molecule to detect the conformational change of DNA molecule induced by dimethyldioctadecylammonium bromide (DDAB) liposomes before the condensation process of DNA begins. DDAB-induced DNA topology changes were investigated by cyclic voltammetry (CV), circular dichroism (CD) and UV-VIS spectrometry. We find that upon binding to DNA, positively charged liposomes induce a conformational transition of DNA molecules from the native B-form to the C motif. Conformational transition in DNA results in the binding modes of MG to DNA, changing and being isolated from DNA to the solution. More stable complexes are formed between DNA and DDAB. That is also proved by the melting study of DNA.  相似文献   
94.
A gallophosphate, Ga3 P3O12 H2O · H2NCH2CH NH2, named GaPO -C4 was hydrothermally synthesized from EDA(ethylenediamine)-Ga2O3-P2O5-H2O systems. The crystal structure of GaPO4-C4 was determined by single crystal X-ray diffraction. The compound crystallizes in monoclinic system with space group P21/n, a=8.688(4)A, b = 17.952(6)A, c=9.104(3)A, β=108.27(3), V=1348.3A3 . The framework of GaPO4-C4 contains three types of P atoms and three types of Ga atoms. Of the three types of gallium atoms, two types are located in distorted trigonal bipyramids and the third type lies at tetrahedral centre. The three-dimensional framework is built of two-dimensional nets which consist of irregular 3-, 4-, 5- and 8-rings and contains 8-ring channels running along [101], in which ethylenediamine templates are located.  相似文献   
95.
Host-guest type complexes of 3,5-dinitrobenzonitrile, 1, with some hydrocarbons like benzene, naphthalene, p-xylene, o-xylene, and aza donor molecules (acridine, phenazine and phenothiazine) have been reported. In all the complexes, 1 forms a host network, yielding channels (in three-dimensional arrangement), which are filled by guest molecules, except in the complex of 1 with p-xylene. In this complex, although a host-guest type network is observed, the molecules of 1 and p-xylene are arranged in such a manner that the hydrocarbon is embedded between the layers of 1, like in inorganic clay structures. All the complexes have been characterized by single crystal X-ray diffraction methods.  相似文献   
96.
雷电回击参数对回击电磁场计算的影响研究   总被引:2,自引:0,他引:2       下载免费PDF全文
 基于BG,TL,MTLL,MTLE和TCS 5种模型,研究了雷电回击通道高度、回击速度和大地电容率对雷电回击电磁场的影响。计算中5种模型采用相同的通道基电流波形,通过计算总结了几种参数对回击电磁场的影响。  相似文献   
97.
漆晓琼  张晓萍 《光子学报》2007,36(B06):14-17
为了计算非线性光纤传输对其信道容量的作用,从信号功率传输特性出发,提出了一种计算非线性光纤信道容量的数值解法,分别得到了非线性信道容量与输入脉冲峰值功率、自发辐射噪音系数、光纤非线性参量及群速色散之间的关系曲线并得出结论:单纯的提高脉冲输入功率并不能提高非线性信道容量,尤其对大功率系统.  相似文献   
98.
Hybrid materials produced by the hydrolytic sol-gel process reveal strong absorption in the spectral region of 1550 nm, mainly due to the high concentration of OH groups. This characteristic constitutes an obstacle to the application of these materials, in particular to telecom integrated optical devices. A simple thermal treatment applied to the device does not contribute to increase the transparency. The real-time influence of temperature and environment humidity on the optical transmission properties of sol-gel organic-inorganic raised channel waveguides is analyzed in order to achieve an understanding of the OH group’s behaviour in the materials. We demonstrate that the level of the optical losses at 1550 nm can significantly be decreased at high temperature. Cooling the sample in dry atmosphere makes it possible to reach a better transparency, which can be useful to improve the performance of hybrid sol-gel optical devices.  相似文献   
99.
A rapid and low-cost means of developing a working prototype for a positive-displacement driven open tubular liquid chromatography (OTLC) analyzer is demonstrated. A novel flow programming and injection strategy was developed and implemented using soft lithography, and evaluated in terms of chromatographic band broadening and efficiency. A separation of two food dyes served as the model sample system. Sample and mobile phase flowed continuously by positive displacement through the OTLC analyzer. Rectangular channels, of dimensions 10 μm deep by 100 μm wide, were micro-fabricated in poly-dimethylsiloxane (PDMS), with the separation portion 6.6 cm long. Using a novel flow programming method, in contrast to electroosmotic flow, sample injection volumes from 0.5 to 10 nl were made in real-time. Band broadening increased substantially for injection volumes over 1 nl. Although underivatized PDMS proved to be a sub-optimal stationary phase, plate heights, H, of 12 μm were experimentally achieved for an unretained analyte with the rectangular channel resulting in a reduced plate height, h, of 1.2. Chromatographic efficiency of the unretained analyte followed the model of an OTLC system limited by mass-transfer in the mobile phase. Flow rates from 6 nl min−1 up to 200 nl min−1 were tested, and van Deemter plots confirmed plate heights were optimum at 6 nl min−1 over the tested flow rate range. Thus, the best separation efficiency, N of 5500 for the 6.6 cm length separation channel, was achieved at the minimum flow rate through the column of 6 nl min−1, or 3 ml year−1. This analyzer is a low-cost sampling and chemical analysis tool that is intended to complement micro-fabricated electrophoretic and related separation devices.  相似文献   
100.
A revised version of Dodge's split-velocity method for numerical calculation of compressible duct flow has been developed. The revision incorporates balancing of mass flow rates on each marching step in order to maintain front-to-back continuity during the calculation. The (chequerboard) zebra algorithm is applied to solution of the three-dimensional continuity equation in conservative form. A second-order A-stable linear multistep method is employed in effecting a marching solution of the parabolized momentum equations. A chequerboard iteration is ued to solve the resulting implicit non-linear systems of finite-difference equations which govern stepwise transition. Qualitive agreement with analytical predictions and experimental results has been obtained for some flows with well-known solutions.  相似文献   
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