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101.
Over the last years, there has been a change of perspective concerning the management of information systems, since they are no longer isolated and need to communicate with others. However, from a semantic point of view, real communication is difficult to achieve due to the heterogeneity of the systems. We present a proposal which, considering information systems are represented by software agents, provides a framework that favors a semantic communication among them, overcoming the heterogeneity of their agent communication languages. The main components of the framework are a suite of ontologies – conceptualizing communication acts – that will be used for generating the communication conversion, and an Event Calculus interpretation of the communications, which will be used for formalizing the notion of a satisfactory conversion. Moreover, we present a motivating example in order to complete the explanation of the whole picture.  相似文献   
102.
A method to prepare water sensitive composites employing crosslinked poly(vinyl amine) (PVAm) and Cu(II) ions as reticulation agent is disclosed in this work. This article presents in detail, the reticulation reaction and its pH dependence, as well as its electrical, rheological, and thermal properties of the PVAm‐Cu(II) composites obtained. The complex bonds formed between the Cu(II) ions and the amine groups of PVAm produce an interesting network of crosslinked structures that generate a microporous morphology when the material is extruded. This characteristic favors fast absorption of water when it is wetted, and a concomitant decrease in its apparent resistivity in a very short period of time. Furthermore, they present an excellent thermal stability and suitable processability. These characteristics make them interesting candidates to design ultra fast water sensors. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
103.
104.
Use of cysteine to remove mercury from shark muscle   总被引:1,自引:0,他引:1  
The efficiency of cysteine to remove mercury from sliced and minced shark was evaluated. Treatment with 0.5% cysteine at pH 2.0–2.5 and subsequent washing with sodium chloride (5%) failed to remove the mercury from the sliced shark. The efficiency of 0.5% cysteine at pH 7.0 in removing mercury from minced shark was 40–45% (dry material), obtained by two of the three methods studied. This removal rate was considered relatively low for it failed to attend to the practical proposal of decontaminating species of fish highly contaminated by mercury. The need for fuller understanding of the mechanisms involved in the removal of mercury by cysteine was also considered.  相似文献   
105.
测量对地有几十伏电压的电路元件的温度是困难的.而且,随着电压的增加,此工作变得更困难.在高EMI环境中测量温度也是困难的.解决这些难题的一个良好方案是靠红外(IR)信号实现温度探头到读出测定位的连接.  相似文献   
106.
The electricity sector, especially in emerging countries, has experienced several transformations, mainly resulting from the increase of electricity demand. This encourages more investment in the generation sector and causes increasing concerns with the development and improvement of tools for static voltage stability analysis of electrical power systems. This paper presents a new geometric parameterization technique for continuation power flow (CPF) that works based on the addition of a parabola that passes through three points in the plane formed by the variables of total real power losses and loading factor. This technique eliminates the Jacobian matrix singularity at the maximum loading point, which allows obtaining the solution trajectory (PV curve) without any need to change the parameter, which is a very common procedure in the currently available CPFs. Intending to define a simple and efficient step size control procedure, the total real power losses values are normalized by its base case value. The results obtained by applying the proposed technique to the IEEE-300 bus system and two real large systems of 638 and 787 buses show its effectiveness.  相似文献   
107.
Antimicrobial peptides (AMPs) are promising candidates to help circumvent antibiotic resistance, which is an increasing clinical problem. Amino‐terminal copper and nickel (ATCUN) binding motifs are known to actively form reactive oxygen species (ROS) upon metal binding. The combination of these two peptidic constructs could lead to a novel class of dual‐acting antimicrobial agents. To test this hypothesis, a set of ATCUN binding motifs were screened for their ability to induce ROS formation, and the most potent were then used to modify AMPs with different modes of action. ATCUN binding motif‐containing derivatives of anoplin (GLLKRIKTLL‐NH2), pro‐apoptotic peptide (PAP; KLAKLAKKLAKLAK‐NH2), and sh‐buforin (RAGLQFPVGRVHRLLRK‐NH2) were synthesized and found to be more active than the parent AMPs against a panel of clinically relevant bacteria. The lower minimum inhibitory concentration (MIC) values for the ATCUN–anoplin peptides are attributed to the higher pore‐forming activity along with their ability to cause ROS‐induced membrane damage. The addition of the ATCUN motifs to PAP also increases its ability to disrupt membranes. DNA damage is the major contributor to the activity of the ATCUN–sh‐buforin peptides. Our findings indicate that the addition of ATCUN motifs to AMPs is a simple strategy that leads to AMPs with higher antibacterial activity and possibly to more potent, usable antibacterial agents.  相似文献   
108.
This work presents a new approach to model the contact between a circular cross section beam and a flat surface. In a finite element environment, when working with beam elements in contact with surfaces, it is common to consider node or line to surface approaches for describing contact. An offset can be included in normal gap function due to beam cross section dimensions. Such a procedure can give good results in frictionless scenarios, but the friction effects are not usually properly treated. When friction plays a role (e.g., rolling problems or alternating rolling/sliding) more elaboration is necessary. It is proposed here a method that considers an offset not only in normal gap. The basic idea is to modify the classical definition of tangential gap function in order to include the effect of rigid body rotation that occurs in a rolling scenario and, furthermore, consider the moment of friction force. This paper presents the new gap function definition and also its consistent linearization for a direct implementation in a Newton‐Raphson method to solve nonlinear structural problems modeled using beam elements. The methodology can be generalized to any interaction involving elements with rotational degrees of freedom. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
109.
In this paper, the generalized differential quadrature (GDQ) method is applied to study the dynamic behavior of functionally graded materials (FGMs) and laminated doubly curved shells and panels of revolution with a free-form meridian. The First-order Shear Deformation Theory (FSDT) is used to analyze the above mentioned moderately thick structural elements. In order to include the effect of the initial curvature a generalization of the Reissner-Mindlin theory, proposed by Toorani and Lakis, is adopted. The governing equations of motion, written in terms of stress resultants, are expressed as functions of five kinematic parameters, by using the constitutive and kinematic relationships. The solution is given in terms of generalized displacement components of points lying on the middle surface of the shell. Simple Rational Bézier curves are used to define the meridian curve of the revolution structures. Firstly, the differential quadrature (DQ) rule is introduced to determine the geometric parameters of the structures with a free-form meridian. Secondly, the discretization of the system by means of the GDQ technique leads to a standard linear eigenvalue problem, where two independent variables are involved. Results are obtained taking the meridional and circumferential co-ordinates into account, without using the Fourier modal expansion methodology. Comparisons between the Reissner-Mindlin and the Toorani-Lakis theory are presented. Furthermore, GDQ results are compared with those obtained by using commercial programs such as Abaqus, Ansys, Nastran, Straus and Pro/Mechanica. Very good agreement is observed. Finally, different lamination schemes are considered to expand the combination of the two functionally graded four-parameter power-law distributions adopted. The treatment is developed within the theory of linear elasticity, when materials are assumed to be isotropic and inhomogeneous through the lamina thickness direction. A two-constituent functionally graded lamina consists of ceramic and metal those are graded through the lamina thickness. A parametric study is performed to illustrate the influence of the parameters on the mechanical behavior of shell and panel structures considered.  相似文献   
110.
Exploratory Analytics is the process of analyzing data for the purpose of forming hypotheses. Patent data sets, because they are relatively large and diverse and because they consist of a mixture of structured and unstructured information present a formidable challenge and a great opportunity in applying exploratory analytics techniques. In this paper we describe methods we have implemented for effective exploratory analytics on patent data sets using an interactive approach and a web based software tool called SIMPLE. We use real-world case studies to demonstrate the effectiveness of our exploratory analytics approach in the discovery of useful information from the patent corpus.  相似文献   
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