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101.
102.
Gluon propagator is investigated for pure Yang-Mills SU(3) gauge theory in field-strength approach. It isfound that instantohs provide a homogeneous solid-like medium background which generates finite nonzero momentumgluon propagator and gluon receives effective mass.  相似文献   
103.
Carbon nanotubes (CNTs) were synthesized by the catalytic decomposition of methane at 773, 873 and 973 K. Structures of these carbon nanotubes were characterized by TEM, HRTEM, XRD and Raman spectra, respectively. The results showed that with the increase of preparation temperature, the d 002 value of the CNTs decreased, while the L a values and the degree of crystallinity of the samples increased. Electrochemical lithium insertion properties of the CNTs used as positive electrodes in CNTs/Li cells were also investigated. The first charge capacities of CNTs/Li cells were 290, 254 and 202 mAh/g for samples produced at 773, 873 and 973 K, respectively. The sample from 773 K showed a larger charge capacity, which is attributed to the accommodation of lithium at microcavities, at edges of graphitic layers and at the surface of single graphitic layers. Its potential hysteresis during Li insertion and deinsertion processes may be related to the interstitial carbon atoms. Electronic Publication  相似文献   
104.
对化学反应进行模拟的关键是找到准确的化学反应抽样几率及位阻因子.本文对国内外应用较普遍的两种计算复合反应位阻因子的方法,即正、逆反应速率法进行了详细的比较,并用不同的分子对这两种方法分别进行了模拟.最后将模拟结果与理论计算结果进行了比较,发现随着稀薄程度的增加;正反应速率法的模拟结果与理论吻合较好.  相似文献   
105.
建立一种测定噻菌灵的荧光分析新方法.铽(Ⅲ)为弱荧光物质,噻菌灵的加入对其荧光强度有显著的增强效应.实验结果表明,荧光增强值△F与噻菌灵的浓度在2-200nmol/L内呈良好的线性关系,r=0.9970,检出限为0.83nmol/L.本法用于实际样本中噻菌灵的测定,结果令人满意.  相似文献   
106.
Starting from famous Schr\"{o}dinger equation within the framework of semi-classical theory of light-matter interaction, we firstly obtain the analytical non-resonant solutions of the driven bipartite system's entanglement dynamics in independent and coherent double pathways. Numerical simulations show that under non-resonant condition, entanglement sudden death and revival between these transition patterns behave quite differently, indicating the utmost importance of transition pathways' interference. Furthermore, the laser pulse's area and detuning exert significant but quite distinct influences on the entanglement dynamics. Our analyses are helpful in manipulating entanglement in current experimental technology.  相似文献   
107.
Data quality monitoring (DQM) plays an important role in data taking at the BESⅢ experiments. DQM is used to monitor detector status and data quality. A DQM framework (DQMF) has been developed to make it possible to reuse the BESⅢ offline reconstruction system in the online environment. In this framework, the DQMF can also simulate a virtual data taking environment, transfer events to the event display, publish histograms to a histogram presenter in a fixed interval, and dump histograms into a ROOT file. The DQMF has been stably running throughout BESⅢ data taking.  相似文献   
108.
The VUV double photoionizations of small molecules (NO,CO,CO2 ,CS2 ,OSC and NH3 ) were investigated with photoionization mass spectroscopy using synchrotron radiation. The double ionization energies of molecules were determined with photoionization efficiency spectroscopy. The total energies of these molecules and their parent dications (NO2+ ,CO2+ ,CO2+2 ,CS2+2 ,OSC2+ and NH2+3 ) were calculated using the Gaussian 03 program and Gaussian 2 calculations. Then,the adiabatic double ionization energies of the molecules were predicated by using high accuracy energy mode. The experimental double ionization energies of these small molecules were all in reasonable agreement with their respective calculated adiabatic double ionization energies. The mechanisms of double photoionization of these molecules were discussed based on a comparison of our experimental results with those predicted theoretically. The equilibrium geometries and harmonic vibrational frequencies of molecules and their parent dications were calculated by using the MP2 (full) method. The differences in configurations between these molecules and their parent dications were also discussed on the basis of theoretical calculations.  相似文献   
109.
Abstract  The adduct of di-triethylammonium, tetrachlorobenzene-1,4-dicarboxylate and tetrachlorobenzene-1,4-dicarboxylic acid, i.e. {2(C2H5)3NH+ C8Cl4O42− H2C8Cl4O4}, crystallizes in triclinic, P-1 with cell dimensions of a = 8.5080(5) ?, b = 8.9789(6) ?, c = 12.5212(8) ?, α = 93.301(1)°, β = 109.107(1)°, γ = 103.565(1)°, V = 869.2(1) ?3 and Z = 2. The C8Cl4O42− and H2C8Cl4O4 moieties link with each other by O–H···O along c axis, C–Cl···O=C along b axis and C–Cl···Cl–C along a axis to form the 3D framework of the crystal structure. The (C2H5)3NH+ cations reside in the cavities of the 3D framework via various intermolecular interactions such as N–H···O, C–H···O and C–H···π. Index Abstract  In the title compound, tetrachlorobenzene-1,4-dicarboxylates and tetrachlorobenzene-1,4-dicarboxylic acids form 3D framework by hydrogen bonds and halogen bonds, and triethylammoniums reside in the voids of the framework via supramolecular interactions .  相似文献   
110.
Primary vertex reconstruction is crucial to estimate the beam profile in collision experiments. We study the principle of an iterative process, called the Kalman filter method, and apply it to primary vertex reconstruction at BESⅢ. A Newton procedure to find the zero point of the distance function's gradient is used for primary vertex finding in 3-dimensional space. Results are obtained based on raw data at BESⅢ.  相似文献   
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