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71.
由于高能激光能量计标定过程中没有标准的能量测量装置和标准的激光源,无法采用常规方法对其进行标校。提出了一种利用现有小能量计从低到高逐级多次传递不确定度的方法,以及一种利用能量等效原理对激光能量计进行标校的方法。不确定度传递法方法简单,但环节较多导致不确定度较大。等效标定法包括电标法和光标法,电标法对设计要求较高,但求解过程相对简单。光标法工程实现难度要低得多,但必须事先对灯组余热及热损失进行测算。等效法的三个条件与误差大小关系紧密,在结构设计中必须严格考虑,它是提高测量准确性的根本,其次要尽量减少不确定度传递的中间环节,最后需要对误差项进行科学分析和测定,在此基础上对这些项进行相应的修正和补偿。 相似文献
72.
挠性陀螺捷联系统场地快速标定 总被引:1,自引:0,他引:1
本文给出了捷联式惯性导航系统一种简单实用的场地标定方法。在系统中,对挠性陀螺仪采用特殊安装,把组合件旋转180°,用两位置数据测出陀螺的标度系数、常值漂移、加速度计零位和系统真方位。在标定过程中不需要对惯性组合件做水平调整。 相似文献
73.
Information on available polystyrene calibration spheres is presented regarding the particle diameter, uncertainty in the size, and the width of the size distribution for particles in a size range between 20 and 100nm. The use of differential mobility analysis for measuring the single primary calibration standard in this size range, 100nm NIST Standard Reference Material®1963, is described along with the key factors in the uncertainty assessment. The issues of differences between international standards and traceability to the NIST Standard are presented. The lack of suitable polystyrene spheres in the 20–40nm size range will be discussed in terms of measurement uncertainty and width of the size distributions. Results on characterizing a new class of molecular particles known as dendrimers will be described and the possibilities of using these as size calibration standards for the size range from 3 to 15nm will be discussed. 相似文献
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The paper presents a novel radial lens distortion modelling method for vision systems. It is based on single images of chessboard
planar pattern, in which calibration points (corners of chessboard squares) are localised. The points, which are situated
near the image centre, where the distortion is negligible, are used to determine undistorted grid of calibration points by
the estimation of homographic matrix. The differences in the localisation of undistorted and distorted points are used to
find parameters of radial model by the linear least square method. Having the distortion model, the dense compensation is
performed with support of bilinear interpolation and a sparse compensation by Newton iterative scheme providing subpixel accuracy. 相似文献
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79.
André Toom 《Journal of statistical physics》2007,129(3):555-566
We prove the existence of an invariant measure for a large class of random processes with discrete time without assuming their
linearity. Our main examples are “processes with variable length”, in which components may appear and disappear in the course
of functioning. One of these examples displays non-uniqueness of invariant measure in a 1-D process. 相似文献
80.
Bahram Hemmateenejad Saeed Yousefinejad 《Analytical and bioanalytical chemistry》2009,394(7):1965-1975
This article describes the use of the net analyte signal (NAS) concept and rank annihilation factor analysis (RAFA) for building
two different multivariate standard addition models called “SANAS” and “SARAF.” In the former, by the definition of a new
subspace, the NAS vector of the analyte of interest in an unknown sample as well as the NAS vectors of samples spiked with
various amounts of the standard solutions are calculated and then their Euclidean norms are plotted against the concentration
of added standard. In this way, a simple linear standard addition graph similar to that in univariate calibration is obtained,
from which the concentration of the analyte in the unknown sample and the analytical figures of merit are readily calculated.
In the SARAF method, the concentration of the analyte in the unknown sample is varied iteratively until the contribution of
the analyte in the response data matrix is completely annihilated. The proposed methods were evaluated by analyzing simulated
absorbance data as well as by the analysis of two indicators in synthetic matrices as experimental data. The resultant predicted
concentrations of unknown samples showed that the SANAS and SARAF methods both produced accurate results with relative errors
of prediction lower than 5% in most cases. 相似文献