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61.
新一代无变压器技术降低了电力集成商(integrators)和公用电力事业机构的系统复杂性,针对两种最常见的大型光伏安装项目——大楼逆变器直接连接项目和用于并网发电输电的公用安装项目,该技术最大限度地提高了其电力传输能力。  相似文献   
62.
The forces produced by small moving organisms have been quantitatively measured by having the organisms move on a polymeric substrate which transduces the applied stress into an optical birefringence signal (photoelastic effect). The optical signal can be rigorously interpreted to give static force measurements, and by calibrating the substrate empirically, dynamic measurements are obtained. The technique measures stresses, forces applied to an area, so it is not possible to determine ultimate sensitivity of the technique for measurements of forces without regard to area. The technique is especially useful when small forces are exerted over very small areas as, for example, may be the situation with moving tissue cells. The technique is noninvasive, requires minimal equipment, and is easily performed on microscopes adapted for polarized light measurements. Gelatin has the highest sensitivity and adaptability as a photoelastic substrate.  相似文献   
63.
The increased need for accurate and repeatable impurity profiling of shallow junction devices places stringent requirements on the profiling procedures and subsequent data reduction. A computer algorithm is described which simplifies the conversion of sheet resistance to impurity profile as required by the anodization and stripping technique. Error magnification commonly found in discrete data differentiation is avoided. Empirical mobility vs carrier concentration expressions are derived from several sources, and a self-contained computer algorithm is given which allows for data reduction on commonly available minicomputers using Fortran. The experimenter is provided with a check on the accuracy of the profile information.  相似文献   
64.
Isothermal melt-spinning of two thermotropic liquid crystalline polymers (TLCPs), a wholly aromatic copolyester KU-9211 (also named K161 from Bayer AG) and an aliphatic containing TLCP, PET/PHB60 (Tennessee Eastman), was studied to analyze the effect of processing conditions on fiber properties. Fibers were melt-spun from a capillary rheometer equipped with an isothermal chamber in which cross-flowed air was used as the cooling medium. The processing variables studied included the extrusion temperature, the extrusion rate, the cooling conditions, and the draw ratio. As-spun fibers were characterized by measuring storage moduli and molecular orientation parameters as a function of draw ratio under various processing conditions. Among the processing variables studied, the draw ratio was the primary factor in determining both the fiber modulus and the molecular orientation. The extrusion rate did not appear to affect the fiber properties within the range studied. The properties of K161 fibers were also dependent on the extrusion and cooling temperatures, while PET/PHB60 fibers were rather insensitive to the processing temperatures within data scatter and temperatures studied. A composite model based on a rigid-rod rotation mechanism and the deformation of nematic domains in an elongational flow field was used to model the experimental results and was compared with other theories available. Conformance of data to the composite model was obtained by use of a single temperature dependent parameter n, suggesting that the rigid-rod rotation mechanism could be used to predict the orientation development of TLCPs. The Halpin-Tsai equations and the orthotropic equation for angular dependence were used to describe the elastic properties of the TLCP fibers.  相似文献   
65.
This commentary reports on a project to explore and evaluate options for Great Lakes governance renewal in anticipation of the 2006–2007 review of the Canada–US Great Lakes Water Quality Agreement (GLWQA). The research included expert interviews and scholarly analysis of governance regimes in 2006, leading to a Great Lakes St. Lawrence River Governance Expert Workshop held in June 2007 (Krantzberg et al. 2007). The two authors have been participants and at times leaders in the institutions this commentary addresses, Krantzberg with the International Joint Commission and Ontario Ministry of the Environment and Manno with the New York Great Lakes Research Consortium and Great Lakes United. Our familiarity with the topic and many of the people involved was helpful in gaining participation and is in itself a rich source of knowledge and experience. In discussing a topic of contemporary controversy, it also understandably can make readers question the objectivity of our assessment. We are also trained in social science scholarship and have taken precautions against biasing the outcomes. This is not intended to be merely a presentation of data. We believe our experience is a net asset in addressing these questions but we leave it to the interested reader to review the reports referenced herein and judge for themselves whether our findings are fairly presented.  相似文献   
66.
Investigated various aspects of eyewitness testimony in a simulated courtroom setting. 80 undergraduates were shown a filmed murder and then testified about their observations in one of several experimental conditions. Testimony was rated for accuracy and quantity. Significant main effects were found for sex of witness, immediacy of testimony (immediately or after a 1-wk delay), testimony structure (unstructured free recall or response to questions), question type (open-ended, leading, and multiple choice), and question bias (positive, negative, and neutral). Results also support a predicted cognitive-set hypothesis, relating accuracy and quantity of testimony to the specificity of the questioning situation. The strong findings attest to the efficacy of empirically investigating aspects of courtroom procedures as a viable research paradigm. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
    
We propose two acceleration methods, namely, Fused and Gram, for reducing out‐of‐core data access when performing randomized singular value decomposition (RSVD) on graphics processing units (GPUs). Out‐of‐core data here are data that are too large to fit into the GPU memory at once. Both methods accelerate GPU‐enabled RSVD using the following three schemes: (1) a highly tuned general matrix‐matrix multiplication (GEMM) scheme for processing out‐of‐core data on GPUs; (2) a data‐access reduction scheme based on one‐dimensional data partition; and (3) a first‐in, first‐out scheme that reduces CPU‐GPU data transfer using the reverse iteration. The Fused method further reduces the amount of out‐of‐core data access by merging two GEMM operations into a single operation. By contrast, the Gram method reduces both in‐core and out‐of‐core data access by explicitly forming the Gram matrix. According to our experimental results, the Fused and Gram methods improved the RSVD performance up to 1.7× and 5.2×, respectively, compared with a straightforward method that deploys schemes (1) and (2) on the GPU. In addition, we present a case study of deploying the Gram method for accelerating robust principal component analysis, a convex optimization problem in machine learning.  相似文献   
68.
    
Efficient modal decomposition of high-dimensional turbulent flow data is an important first step for data reduction, analysis, and low-dimensional predictive modeling. The conventional modal decomposition techniques, such as proper orthogonal and dynamic mode decompositions, aim to represent the system response using spatially global basis vectors that span a broad spatial domain. A significant challenge facing approaches based on global domain decomposition is the rapid increase in both the amount of training data and the number of modes that must be retained for an accurate representation of convection dominated turbulent flows. An alternative generalized finite element (GFEM) based approach is explored for efficient representation of high-dimensional fluid flow data. Here, the standard finite element interpolation method is enriched with numerical functions that are learned from a small amount of high-fidelity training data over spatially localized subdomains. The GFEM approach is demonstrated on a 3D flow past a cylinder at Reynolds number of 100 000 and flows inside a 2D lid-driven cavity over a range of Reynolds numbers. Compared with a global proper orthogonal decomposition, the GFEM-based approach increases efficiency in reconstructing the datasets while also substantially reducing the amounts of training data.  相似文献   
69.
    
Chimeric antigen receptor (CAR) T cell therapy is an innovative immunotherapy for treating cancers in both children and adults with proven utility in numerous clinical trials. Significantly, some CAR T cell therapies have now been approved by relevant national regulatory bodies across numerous countries for clinical therapeutic use outside of clinical trials. One such recently licensed product is tisagenlecleucel, a CAR T therapy approved for the treatment of B-cell acute lymphoblastic leukemia (B-ALL) using autologous T cells from the patient. The genetically engineered T cells target a protein called CD19, common to B cells, through a CAR incorporating a 4-1BB costimulatory domain to improve response. Since tisagenlecleucel is now a standard of care treatment for B-ALL, it is clinically essential to be able to accurately monitor these CAR T cells in patients. Assessment of the copy number variant (CNV) of the CAR T cell products allows this within a clinically acceptable timeframe for optimal patient benefit. However, no standardized method with high reproducibility and efficiency has been described within a routine clinical laboratory setting. Here, we demonstrated a novel digital droplet PCR (ddPCR)-based methodology for the study of CNV (ddPCR-CNV) in 4-1BB CD19-specific CAR T cells with universal applicability across clinical diagnostic laboratories.  相似文献   
70.
    
The HER2/neu signaling pathway is one of the most frequently mutated in human cancer. Although therapeutics targeting this pathway have good efficacy, cancer cells frequently develop resistance. The HER2 gene encodes the full-length HER2 protein, as well as smaller c-terminal fragments (CTFs), which have been shown to be a cause of resistance. Here, we show that HER2 CTFs, exclusive from the full-length HER2 protein, are generated via internal translation of the full-length HER2 mRNA and identify regions which are required for this mechanism to occur. These regions of the HER2 mRNA may present novel sites for therapeutic intervention via small molecules or antisense oligonucleotides (ASOs).  相似文献   
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