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81.
The induced generalized OWA operator 总被引:1,自引:0,他引:1
We present the induced generalized ordered weighted averaging (IGOWA) operator. It is a new aggregation operator that generalizes the OWA operator, including the main characteristics of both the generalized OWA and the induced OWA operator. This operator uses generalized means and order-inducing variables in the reordering process. It provides a very general formulation that includes as special cases a wide range of aggregation operators, including all the particular cases of the IOWA and the GOWA operator, the induced ordered weighted geometric (IOWG) operator and the induced ordered weighted quadratic averaging (IOWQA) operator. We further generalize the IGOWA operator via quasi-arithmetic means. The result is the Quasi-IOWA operator. Finally, we present a numerical example to illustrate the new approach in a financial decision-making problem. 相似文献
82.
The usefulness of Monte Carlo simulation of aggregation phenomena is discussed and applied in analysis of the structure of particle deposits. The structural properties of depositional aggregates in single and multiparticle regimes are obtained and expressed in terms of fractal geometrical concepts. These properties are related to the Peclet number and to the concentration in the non-aggregate (vapour) phase. The topological properties of the aggregates are obtained from random walk simulation, thus confirming the anomalous properties of these structures, even in the case of multiparticle simulations, i.e. for high values of the concentration in the vapour phase. 相似文献
83.
Rocío de Andrés José Luis García-Lapresta Luis Martínez 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2010,14(1):21-34
The performance appraisal is a relevant process to keep and improve the competitiveness of companies in nowadays. In spite
of this relevance, the current performance appraisal models are not sufficiently well-defined either designed for the evaluation
framework in which they are defined. This paper proposes a performance appraisal model where the assessments are modelled
by means of linguistic information provided by different sets of reviewers in order to manage the uncertainty and subjectivity
of such assessments. Therefore, the reviewers could express their assessments in different linguistic scales according to
their knowledge about the evaluated employees, defining a multi-granular linguistic evaluation framework. Additionally, the
proposed model will manage the multi-granular linguistic labels provided by appraisers in order to compute collective assessments
about the employees that will be used by the management team to make the final decision about them. 相似文献
84.
Maren Daschner De Tercero 《Chemical Engineering Communications》2013,200(1-2):234-251
Recent studies have reported that full monolayers of L-α-dilaurylphosphatidylcholine (L-DLPC) and D-α-dipalmitoylphosphatidylcholine (D-DPPC) formed at interfaces between thermotropic liquid crystals (LCs) and aqueous phases lead to homeotropic (perpendicular) orientations of nematic LCs and that specific binding of proteins to these interfaces (such as phospholipase A 2 binding to D-DPPC) can trigger orientational ordering transitions in the liquid crystals. We report on the nonspecific interactions of proteins with aqueous-LC interfaces decorated with partial monolayer coverage of L-DLPC. Whereas nonspecific interactions of four proteins (cytochrome c, bovine serum albumin, immunoglobulins, and neutravidin) do not perturb the ordering of the LC when a full monolayer of L-DLPC is assembled at the aqueous-LC interface, we observe patterned orientational transitions in the LC that reflect penetration of proteins into the interface of the LC with partial monolayer coverage of L-DLPC. The spatial patterns formed by the proteins and lipids at the interface are surprisingly complex, and in some cases the protein domains are found to compartmentalize lipid within the interfaces. These results suggest that phospholipid-decorated interfaces between thermotropic liquid crystals and aqueous phases offer the basis of a simple and versatile tool to study the spatial organization and dynamics of protein networks formed at mobile, lipid-decorated interfaces. 相似文献
85.
油包水型乳化液剪切破乳的实验 总被引:1,自引:0,他引:1
通过设计Couette双圆筒装置形成薄层纯剪切流场,其剪切强度可通过内筒转速调节,对油包水型乳
化液剪切破乳的可行性进行研究。从流体动力学角度分析单个液滴受力,建立其仿射形变模型并经实验验证,与
TaylorGI和CoxRG的理论模型基本一致。实验结果表明,将剪切作用引入流场中有利于液滴聚合,当内筒转速
为50~150r/min(剪应力8.67~26.01Pa)时,液滴最大直径和平均直径比未引入剪切力场时高,说明只有在一定剪
切范围内,剪切才能促进液滴聚合。因此,为了提高油水乳化液分离效率,可在油水分离设备中引入适当的剪切力
场。 相似文献
86.
Weighted voting is the commonly used strategy for combining predictions in pairwise classification. Even though it shows good classification performance in practice, it is often criticized for lacking a sound theoretical justification. In this paper, we study the problem of combining predictions within a formal framework of label ranking and, under some model assumptions, derive a generalized voting strategy in which predictions are properly adapted according to the strengths of the corresponding base classifiers. We call this strategy adaptive voting and show that it is optimal in the sense of yielding a MAP prediction of the class label of a test instance. Moreover, we offer a theoretical justification for weighted voting by showing that it yields a good approximation of the optimal adaptive voting prediction. This result is further corroborated by empirical evidence from experiments with real and synthetic data sets showing that, even though adaptive voting is sometimes able to achieve consistent improvements, weighted voting is in general quite competitive, all the more in cases where the aforementioned model assumptions underlying adaptive voting are not met. In this sense, weighted voting appears to be a more robust aggregation strategy. 相似文献
87.
2-Hydroxy-1,4-napthoquinone(lawsone) natural red-orange dye was extracted from fresh henna(Lawsonia inermis) leaves in an alkaline media.The lawsone-surfactant solubilization constants(K_(LS))were calculated for the first time by using cationic cetyltrimethylammonium bromide(CTAB) and anionic sodium dodecyl sulphate(SDS).The standard free energy,concentration of solubilized lawsone and number of lawsone molecules solubilized into micelles were calculated and discussed.Surface excess,minimum surface area per molecule,surface pressure,free energy(adsorption and aggregation) and equilibrium constants of different states were determined from tensiometry.Different metal ions(Ag~+,Co~(2+),Cu~(2+),Ni~(2+),Fe~(3+),Zn~(2+) and Al~(3+)) were used to determine the complex forming ability with lawsone.Out of these,Ag~+ ions have strong binding capacity with lawsone.The adsorption of lawsone on the surface of glass with silver ions in presence of CTAB was also observed at pH 9.0.The pseudo-first, secondorder kinetic equation,intraparticles diffusion and Elovich models were used to determine the kinetics of lawsone adsorption onto the surface of glass and a probable mechanism has been discussed.Lawsone adsorption followed second-order kinetic equation(k_2=0.019 g·mg~(-1)·min~(-1)). 相似文献
88.
Xiu-Jie Yang Peng Zhang Wenjiao Lv Ting Zhou Peng Li Mingwei Zhao 《Journal of surfactants and detergents》2019,22(3):515-523
Three kinds of imidazolium-based amino acid ionic liquid surfactants (AAILS), 1-tetradecyl-3-methylimidazolium L-aminopropionic acid salt ([C14mim][Ala]), 1-tetradecyl-3-methylimidazolium L-2-pyrrolidinecarboxylic acid salt ([C14mim][Pro]), and 1-tetradecyl-3-methylimidazolium L-aminohydrocinnamic acid salt ([C14mim][Phe]), were synthesized by employing natural amino acids as counterions. Their adsorption and self-aggregation behaviors in aqueous solution were investigated systematically by means of surface tension and electrical conductivity measurements. Surface tension results indicate that surface properties and micellization behavior of AAILS are significantly affected by counterions. The micellization of [C14mim][Pro] and [C14mim][Phe] is entropy-driven at low temperatures but enthalpy-driven at high temperatures, whereas [C14mim][Ala] is enthalpy-driven throughout the whole temperature range, owing to the variation in hydrophobicity and size of amino acid counterions. The surface activity of [C14mim][Phe] is superior to that of conventional imidazolium-based ionic liquid surfactants with the same hydrocarbon chain length, 1-tetradecyl-3-methylimidazolium bromide (C14mimBr), indicating that the aromatic counterion can promote the micellar formation process. 相似文献
89.
The rheological behaviour of calcite suspensions made of particles with different size distributions, obtained by means of a wet comminution process, have been studied versus the operating conditions (volume concentration, use of dispersing agent). The suspension properties (size distribution, specific surface area [SSA]) were investigated in order to characterize the microstructure of the aggregated suspensions. The suspension acts as a thinning fluid with a yield value, and the viscosity increases when the particle size decreases (colloidal dispersions) due to attractive interparticle forces. The use of a polyelectrolyte (sodium polyacrylate [SPA]) during the size-reduction process allows strong reduction of the viscosity of the ground suspensions. The polymer is adsorbed onto the surface of the particles and, consequently, prevents aggregation and allows improvement of the process efficiency. 相似文献
90.