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991.
992.
一种新的膜系设计方法——Needle法 总被引:10,自引:2,他引:8
Needle法是一种先进的膜系设计方法,它克服了传统优化方法容易陷入局部极值的缺点,通过在膜系中插入薄层,使得评价函数降低,优化设计可以从任意给定的一层膜开始,文中给出了其数学模型及详细的推导。 相似文献
993.
The general context of this paper is to support the design of spillways by a direct mathematical approach instead of trial-and-error methods. First, a two-dimensional model is formulated to determine the free surface and the discharge for a stationary, incompressible, homogeneous, non-viscous and irrotational flow over a fixed spillway. The flow satisfies the Laplace equation and the Bernoulli equation (potential flow). An important feature of the model is that it can be extended to design the spillway structure when the spillway is not fixed but the pressure on the spillway is described by a cavitation criterion. Next, the continuous model is discretized by the boundary element method (BEM). We use a non-linear programming algorithm to calculate the pressures and the shape of the spillway. A computer-aided design package is developed on a PC using the equations describing the free surface, the BEM and standard optimization techniques. The input and output of the model are realized using graphical routines. Finally, we discuss the convergence and the computation time of the algorithms. 相似文献
994.
In this paper we consider experimental situations requiring usage of a row-column design where v treatments are to be applied to experimental units arranged in b
1 rows and b
2 columns where row i has size k
1i
, i=1,..., b
1 and column j has size k
2j
, j=1,..., b
2. Conditions analogous to those given in Kunert (1983, Ann. Statis., 11, 247–257) and Cheng (1978, Ann. Statist., 6, 1262–1272) are given which can often be used to establish the optimality of a given row-column design from the optimality of an associated block design. In addition, sufficient conditions are derived which guarantee the existence of an optimal row-column design which can be constructed by appropriately arranging treatments within blocks of an optimal block design.Visiting from the Indian Statistical Institute. 相似文献
995.
Robert Ehrlich 《Physics in Perspective (PIP)》2006,8(1):83-89
I compare the theory of intelligent design to string theory to see on what basis, if any, only the former can be justifiably
excluded as being scientific.We shall see that the classic criterion of testability or falsifiability is sometimes not so
straightforward, and that there are other criteria to help us make such a distinction. 相似文献
996.
We consider the design of multiple transit lines in a network and present a mixed integer formulation for this multiple-route
transit network design problem (MRTNDP). With the introduction of node labels, the formulation can exploit the route structure
and hence attains efficiency in obtaining a cost minimizing transit network design.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
997.
Yury J. Ionin 《Discrete Mathematics》2006,306(14):1557-1568
The first infinite families of symmetric designs were obtained from finite projective geometries, Hadamard matrices, and difference sets. In this paper we describe two general methods of constructing symmetric designs that give rise to the parameters of all other known infinite families of symmetric designs. The method of global decomposition produces an incidence matrix of a symmetric design as a block matrix with each block being a zero matrix or an incidence matrix of a smaller symmetric design. The method of local decomposition represents incidence matrices of a residual and a derived design of a symmetric design as block matrices with each block being a zero matrix or an incidence matrix of a smaller residual or derived design, respectively. 相似文献
998.
There is a growing market for oligosaccharides as sweeteners, prebiotics, anticariogenic compounds, and immunostimulating
agents in both food and pharmaceutical industries. Interest in novel carbohydrate-based products has grown because of their
reduced toxicity and low immune response. Cellobiose is potentially valuable as a nondigestible sugar. The reaction of cellobiose,
as an acceptor with a sucrose as a donor, catalyzed by a dextransucrase from Leuconostoc mesenteroides B-512FMCM, produced a series of cellobio-oligosaccharides. This production system was optimized using a Box–Behnken experimental
design for 289 mM of sucrose and 250 mM of cellobiose and 54 U of the enzyme at pH 5.2 and 30 °C, to produce maximum yields
of oligosaccharide. 相似文献
999.
Summary Moment analysis is used to study two component perturbation chromatography with linear non-equilibrium adsorption. The interference between components is included through the adsorption equilibrium. In this work, the expressions for the first and second moments of two component pertubations have been obtained for the first time. They are just the vectorization of those for the single component system, and they clearly show the interference between components. These results could be applied to establish an experimental procedure to measure adsorption equilibrium and kinetic data. 相似文献
1000.
高分辨方位估计特征分解法是一类性能良好的方法,本文从水下阵列信号处理的实际应用出发,对这类方法进行了C30硬件实验研究,所得结果为高分辨技术的实际应用提供了重要依据文中构造了高分辨方位估计的C30硬件实验系统;并实现了高分辨方位估计的Pisarenko法、MUSIC法、Johnson法和最小摸(Mininorm)法;对高分辨实验系统进行了仿真实验和消声水池实验,并测试了各特征分解法的运行时间.结果表明,高分辨C30实验系统表现了良好的方位估计统计性能和实时性能 相似文献