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161.
A simple chemical method for stabilization of rice bran   总被引:11,自引:0,他引:11  
A new simple chemical method for stabilization of rice bran is described. The process, based on the principle that lipase activity will be low at low pH, uses hydrochloric acid at 40 l/ton of bran for lowering the pH of rice bran from 6.9–6.0 to 4.0. The acid can be applied easily by sprinkling or spraying. The operation on small lots can be done by hand mixing of bran, but it is more efficient and effective if mechanical mixing, like a rotary or a trough mixer, is used. This simple method, which takes less than 4 min for a batch of 15 kg, will be useful for stabilization of rice bran in rice mills or where steam or electricity is unavailable. The process is being evaluated in commercial trials.  相似文献   
162.
This paper focuses on space efficient representations of rooted trees that permit basic navigation in constant time. While most of the previous work has focused on binary trees, we turn our attention to trees of higher degree. We consider both cardinal trees (or k-ary tries), where each node has k slots, labelled {1,...,k}, each of which may have a reference to a child, and ordinal trees, where the children of each node are simply ordered. Our representations use a number of bits close to the information theoretic lower bound and support operations in constant time. For ordinal trees we support the operations of finding the degree, parent, ith child, and subtree size. For cardinal trees the structure also supports finding the child labelled i of a given node apart from the ordinal tree operations. These representations also provide a mapping from the n nodes of the tree onto the integers {1, ..., n}, giving unique labels to the nodes of the tree. This labelling can be used to store satellite information with the nodes efficiently.  相似文献   
163.
Optimal reconfiguration of Radial Distribution System (RDS) is done under the umbrella of Supervisory Control and Data Acquisition (SCADA) systems to achieve the best voltage profile and minimal kW losses amongst several objectives. This problem requires the determination of the best combination of feeders from each loop in the RDS to be switched out such that the resulting RDS gives the optimal performance in the chosen circumstance. The problem has a discontinuous solution space and certain problem variables assume discrete values of zero or one. This paper proposes a method that uses fuzzy adaptation of Evolutionary Programming (FEP) as a solution technique. FEP technique has been chosen as it is particularly suited while solving optimization problems with discontinuous solution space and when the global optimum is desired. Fuzzy adaptation of EP is necessitated while considering optimization of multiple objectives. The proposed method is tested on established RDS and results are presented.  相似文献   
164.
ABSTRACT

Chlorinated water from River Ganga is the main source of drinking water in Kanpur, India. But, this water contains a significant amount of disinfection by-products (DBPs) that include haloacetic acids (HAAs) as a major contributor, which pose a carcinogenic risk on long-term ingestion. Therefore, in order to control HAAs formation, different combinations of ozonation and bio-activated carbon filtration (BAC-filtration) were studied. The results elucidate that slight ozonation followed by BAC-filtration proved effective in reducing (75.8%) HAAs formation and meet the USEPA drinking standards. These findings open a path to explore cost-effective treatment techniques in continuous mode for safe drinking water.  相似文献   
165.
Background: Autologous fat transfer in the form of lipoaspirates for the reconstruction of the breast after breast cancer surgery is a commonly used procedure in plastic surgery. However, concerns regarding the oncologic risk of nutrient-rich fat tissue are widely debated. Previous studies have primarily focused on studying the interaction between adipose-derived stem cells (ASCs) and breast cancer cells. Methods: In this study, we performed a comprehensive analysis of the paracrine- and contact-based interactions between lipoaspirates, ASCs and breast cancer cell lines. An inverted flask culture method was used to study the contact-based interaction between lipoaspirates and breast cancer cells, while GFP-expressing breast cancer cell lines were generated to study the cell–cell contact interaction with ASCs. Three different human breast cancer cell lines, MCF-7, MDA-MB-231 and BT-474, were studied. We analyzed the impact of these interactions on the proliferation, cell cycle and epithelial-to-mesenchymal (EMT) transition of the breast cancer cells. Results: Our results revealed that both lipoaspirates and ASCs do not increase the proliferation rate of the breast cancer cells either through paracrine- or contact-dependent interactions. We observed that lipoaspirates selectively inhibit the proliferation of MCF-7 cells in contact co-culture, driven by the retinoblastoma (Rb) protein activity mediating cell cycle arrest. Additionally, ASCs inhibited MDA-MB-231 breast cancer cell proliferation in cell–cell contact-dependent interactions. Quantitative real-time PCR revealed no significant increase in the EMT-related genes in breast cancer cells upon co-culture with ASCs. Conclusion: In conclusion, this study provides evidence of the non-oncogenic character of lipoaspirates and supports the safety of clinical fat grafting in breast reconstruction after oncological surgical procedures. In vivo studies in appropriate animal models and long-term post-operative clinical data from patients are essential to reach the final safety recommendations.  相似文献   
166.
The present study describes the effect of thermally assisted machining (TAM) parameters on the cutting force, tool wear and surface integrity characteristics (surface roughness, surface topography, and microhardness) of Inconel 718. An inexpensive flame heating technique using oxy-acetylene flame is used to heat the workpiece material. The TAM parameters such as cutting speed, feed rate, depth of cut, and workpiece temperature were selected as process parameters over cutting force, tool wear and surface integrity characteristics.The experimental results reveal that the cutting forces and surface roughness decrease with increases in cutting speed and workpiece temperature, while the workpiece temperature increases as tool wear decreases. The tool wear mechanisms observed were abrasive, adhesive, diffusion and notch wear. The XRD results of thermally assisted machining reveal that neither phase change nor broadening of the peaks were observed at different machining conditions.  相似文献   
167.
Modeling edges at subpixel accuracy using the local energy approach   总被引:8,自引:0,他引:8  
In this paper we describe a new technique for ID and 2D edge feature extraction to subpixel accuracy using edge models and the local energy approach. A candidate edge is modeled as one of a number of parametric edge models, and the fit is refined by a least-squared error fitting technique  相似文献   
168.
169.
为了满足市场对更高性能、更小体积及更低成本和功耗不断增长的需求,系统设计人员需要将更高级别的混合信号功能集成到系统级芯片(SoC)中。随着这些SoC设计中混合信号器件的增加,基本的功能验证在半导体的早期制备中变得十分重要。没有这种验证,系统设计人员将需要为半导体制备  相似文献   
170.
Recent developments in grinding of advanced materials   总被引:2,自引:2,他引:0  
This article discusses the recent developments in grinding of advanced materials. Eighty-four journal papers published recently are briefly introduced. The topics are advances in grinding of brittle materials, grinding of silicon, dressing/truing of grinding wheels, grinding fluids, grinding of mirrors and vibration-assisted grinding, measuring/monitoring of grinding, optimization of grinding, modelling and simulation of grinding, and size effect. Ductile mode grinding of brittle materials has been and will continue to be an intensive research area because of its increasing industrial applications and academic demands for fundamental understanding of the ductile mode grinding mechanism. Highly precision manufacturing of silicon substrates faces more and more new challenges. Grinding of silicon continues to be a popular research topic. Using lasers to true and dress grinding wheels has attracted great research interest, because it has significant advantages over mechanical processes. Environmentally friendly grinding fluids are increasingly highly demanded. Vibration-assisted grinding is promising. Monitoring, modelling and optimization of grinding processes help to understand grinding mechanisms and achieve better grinding performance. The size effect is more prominent in grinding than turning and can be used for obtaining a controlled work-hardening surface layer with higher wear resistance and hardness.  相似文献   
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