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91.
用于三发弹丸同时着靶的密集度测量方法   总被引:3,自引:0,他引:3  
董涛  华灯鑫  李言  倪晋平 《光子学报》2014,42(11):1329-1333
  相似文献   
92.
This paper studies vertical integration in serial supply chains with a wholesale price contract. We consider a business environment where the contracting leader may be endogenously changed before and after forming the integration. A cooperative game is formulated to normatively analyze the stable and fair profit allocations under the grand coalition in such an environment. Our main result demonstrates that vertical integration is stable when all members are pessimistic in the sense that they are sure that they will not become the contracting leader if they deviate from the grand coalition. We find that in this case, the grand coalition’s profit must be allocated more to the retailer and the members with higher costs. Nevertheless, we also show the conditions under which the upstream manufacturer can have strong power as in traditional supply chains.  相似文献   
93.
A sensitive way to determine levofloxacin using a sensor based on vertical aligned carbon nanotubes is described. The morphology and the electrochemical performance of the electrodes were characterised by atomic force microscopy, cyclic voltammetry and square wave voltammetry. A scan‐rate study and electrochemical impedance spectroscopy showed that the levofloxacin oxidation product is adsorbed on the electrode surface. Differential pulse voltammetry in phosphate‐buffer solution allowed the development of a method to determine levofloxacin levels in the range of 1.0–10.0 µmol L?1, with a detection limit of 75.2 nmol L?1. The proposed sensor was successfully applied in the determination of levofloxacin in urine, and the obtained results were in full agreement with those from the HPLC procedure.  相似文献   
94.
Laser interferometry based on self-mixing effect widely used to measure displacement, velocity, vibration and distance due to compactness, non-contact, as well as low cost. An important use of the self-mixing effect inside a laser diode is in optical self-mixing vibrometer. We have experimentally investigated self-mixing interference produced by the feedback of light from a vibrated target into a vertical-cavity surface-emitting laser for sensing applications. In this paper, the self-mixing vibrometer employing different feedback regime is discussed and a theoretical analysis is also proposed. Numerical analysis focused on the distortion self-mixing waveform. Numerical analysis and experimental results show that mode-hop occurs when the laser self-mixing vibrometer employing at high feedback level.  相似文献   
95.
For modeling multi-phase where the dispersed phase plays a major role in determining the flow structure and inter phase transfer quantities, the size distribution of the bubbles has to be considered. This can be done by extension of the mass balance equation to a population balance equation. In this work, a least squares spectral method is tested for predicting the evolution of the dispersed phase in a vertical two-phase bubbly flow. The least squares spectral method consists in minimizing the L2 norm of the residual over the simulation domain. The results are compared with experimental data obtained for two different initial bubble distributions.  相似文献   
96.
基态Se2x(x=0,-1,+1,+2)分子离子的势能函数与垂直电离势   总被引:2,自引:0,他引:2  
用原子分子反应静力学原理推导出了Se2x(x=0,+1,-1,+2)分子离子的基态电子状态及其离解极限.在6-311G**水平基础上,用B3LYP方法计算了Se2x(x=0,-1,+1,+2)分子离子的基态电子状态的平衡几何Re和离解能De及谐振频率;并在计算出来的一系列单点能基础上,用正规方程组拟合Murrell-Sorbie(M-S)势能函数,得到相应态的解析势能函数,由此计算对应的光谱参数和力学性质;计算了Se2+、Se22+的垂直电离势;计算表明Se2x(x=0,+1,-1,+2)分子离子是可稳定存在的.  相似文献   
97.
The purpose of this paper is to study the problem of detection of vertical and oblique faults in explicit surfaces. First, we characterize the finite jump discontinuities of a univariate function in terms of the divergence of sequences related to the slopes of least-squares polynomial approximations of the function. Then, we propose an algorithm to locate the finite jump discontinuities of a univariate function and its first derivative from a finite set of scattered data values of the function. As a consequence, we derive a method to detect vertical and oblique faults in explicit surfaces when the data sets are distributed along lines. We finally present some numerical and graphical examples.  相似文献   
98.
This review describes the recent advancements in the field of the vertical aligned (VA) liquid crystal displays. The process and formation of different vertical alignment modes such as conventional VA, patterned VA, multi-domain VA, and polymer stabilised VA etc are widely discussed. Vertical alignment of liquid crystal due to nano particle dispersion in LC host, bifunctional PR-SAM formed by silane coupling reaction to oxide surfaces, azo dye etc., are also highlighted and discussed. Overall, the article highlights the advances in the research of vertical aligned liquid crystal in terms of their scientific and technological aspects.  相似文献   
99.
《印度化学会志》2023,100(1):100818
In the present paper, the heat generating and/or absorption as well as thermo-diffusion on the unsteady free convection MHD gyrating flow of radiation and chemical reactive second grade fluid past an unbounded perpendicular plate during absorbent medium have been discussed. Here, it is assumed that, the confining plate has the ramped wall temperature with ramped surface concentration and isothermal temperature with ramped surface concentration. The analytical solutions for the governing equations are found by utilization of Laplace transformation methodology. The velocity, temperature and concentration profiles are analyzed with quite few figures. It is determined that, velocity, temperature and concentration distribution sketches in case of ramped temperature as well as ramped surface concentration are not as much of as those of isothermal temperature as well as ramped surface concentration. In addition to the idioms of skin friction, Nusselt number as well as Sherwood number are achieved and characterized numerically with tabular format.  相似文献   
100.
由于二氧化氮(NO2)在大气的物理和化学机制进程中有着十分重要的作用,并且对环境、气候以及人体健康产生影响,合理、有效地监测和控制大气中NO2浓度已成为十分重要的课题。地基多轴差分吸收光谱(MAX-DOAS)仪是利用太阳散射光的被动DOAS仪器,相较于小范围测量的点式仪器、利用光源和反射装置的主动DOAS仪器,具有时间分辨率高、高灵敏度、测量范围广和不受搭建平台制约等优势特点。2018年在北京中国气象科学研究院(116.32°E,39.95°N)开展了基于地基MAX-DOAS的对流层NO2全年连续观测,采集得到原始吸收光谱并运用光谱处理软件QDOAS进行反演得到NO2斜柱浓度(SCD),选择较为简单的几何近似方法计算求出大气质量因子(AMF),从而将NO2SCD转换为垂直柱浓度(VCD),据此研究分析了北京地区NO2VCD月均值和季节均值变化、季节的日平均变化以及一周内日平均变化的特征。结果表明,北京地区对流层NO2VCD随季节变化较为明显,呈现冬季最高而夏季最低的趋势,其中冬季季节均值达到2.94×1016 molec·cm-2,为夏季的1.6倍,不同季节的日均变化一般在下午表现出明显的差异,最大相差为2.17×1016 molec·cm-2。一周内每日的浓度变化有一定规律性,周日平均浓度较其他时间降低17%左右,出现了一定程度的周末效应。通过将地基MAX-DOAS观测结果和地面国控站点官园监测站(116.339°E,39.929°N)2018全年数据结果进行对比,显示出两者变化趋势具有好的一致性,相关系数r可达0.81。研究表明,地基MAX-DOAS不仅可以对区域污染气体如NO2的实时快速监测及变化规律的研究分析提供一种有效手段,也可以对其他数据来源进行校验。  相似文献   
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