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701.
In many branches of industry, most of manufacturing efforts are directed toward producing objects of specific forms and dimensions. Dimensional measurement is an important part of the production cycle, to check products compliance with specifications. For this, many substantial improvements in the existing technologies have been made, and new measuring systems have been introduced. This paper briefly introduces a recent measuring system—mobile spatial coordinate measuring system (MScMS)—which is suitable for performing dimensional measurements of large-size objects (dimension on the order of tens of meters). MScMS, thanks to its distributed wireless sensor network nature, is portable and can be easily arranged around the measured object. Furthermore, it does not require complex setup operations before being ready to perform measurements. After describing how the system works, we will compare it with well-tested and widespread instruments such as traditional coordinate measuring machines (CMMs), showing analogies and differences. The comparison is structured on the basis of different criteria, which are analyzed in detail in the first part of the paper. Although being able to perform similar measurements, CMMs and MScMS are different in technological features. CMMs are able to achieve higher level of accuracy, while MScMS is more flexible, cheap, and can be important to simplify the current measuring practices within large-scale industrial metrology. It can be concluded that these systems can easily coexist, as each system is suitable for specific applications.  相似文献   
702.
Samples of two potato cultivars (Agria and Merit), cultivated either conventionally or organically, were analysed to evaluate their suitability to transformation into powder. Agria cultivar potatoes from the conventional farming were selected as the most suitable for drying process both for their high-dry matter and good nutritional value. Blanching resulted in the most effective treatment to prevent potato browning. The potato powder was obtained by means of a drum dryer using different process parameters (temperature, time and product thickness) to minimise thermal damage on the final product. The effects of these different processes were evaluated by analysing some quality indicators, as final moisture, nutrients (carbohydrates, proteins and amino acids) and colour of the powder, and rheological properties of the rehydrated puree. The results of such analyses showed that the lower the process temperature, the better the powder quality.  相似文献   
703.
The design and synthesis of new N1‐substituted 3‐carboxy‐ and 3‐phosphonopyrazoline and pyrazole amino acids that target the glutamate binding site of NMDA receptors are described. An analysis of the stereochemical requirements for high‐affinity interaction with these receptors was performed. We identified two highly potent and selective competitive NMDA receptor antagonists, (5SR)‐ 1 and (5SR)‐ 4 , which exhibit good in vitro neuroprotective activity and in vivo anticonvulsant activity by i.p. administration, suggesting that these molecules may have potential use as therapeutic agents.  相似文献   
704.
As part of the Euratom project TEMPEST (Testing and Enhanced Modelling of Passive Evolutionary Systems Technology for Containment Cooling), a series of five tests was performed in the PANDA facility to experimentally investigate the distribution of hydrogen inside the containment and its impact on the performance of the Passive Containment Cooling System (PCCS) designed for the Economic Simplified Boiling Water Reactor (ESBWR). In a postulated severe accident a large amount of hydrogen could be released in the Reactor Pressure Vessel (RPV) as a consequence of the cladding Metal-Water (M-W) reaction and discharged together with steam to the Drywell (DW) compartment. The retention of hydrogen in the DW, instead to be vented in the Wetwell (WW), has a positive effect toward the mitigation of the system pressure build-up. Hydrogen retention in the DW is a consequence of the stratification phenomena driven by the steam-hydrogen density difference. The paper presents the experimental results of the integral Test T1.2 performed in the PANDA facility. Helium was used to simulate hydrogen and the specific PANDA facility configuration included a dead-end volume, allowing for retaining a portion of the released helium in the DW compartment. The results from Test T1.2 showed that the containment end pressure is mainly determined by the redistribution of non-condensable gas inside the containment system and the temporary deterioration of the PCCS performance during the helium release phase plays a minor role.  相似文献   
705.
This paper deals with the implementation of an innovative measurement instrument for power measurement in Digital Video Broadcasting Terrestrial (DVB-T) systems.  相似文献   
706.
This paper develops a structured comparison among a sample of European researchers in the field of production technology and manufacturing systems on the basis of two research outputs: scientific publications and patents. Researchers are evaluated and compared by a variegated set of indicators concerning (1) the output of individual researchers and (2) that of groups of researchers from the same country. Whilst not claiming to be exhaustive, the results of this preliminary study provide a rough indication of the publishing and patenting activity of European researchers in the field of interest, identifying (dis)similarities between different countries with regard to their inclination to publishing and patenting. Of particular interest is a proposal for aggregating analysis results by means of maps based on publication and patent indicators. A large amount of empirical data are presented and discussed.  相似文献   
707.
708.
Glycosylation is a complex post-translational modification that conveys functional diversity to glycoconjugates. Cell surface glycosylation mediates several biological activities such as induction of the intracellular signaling pathway and pathogen recognition. Red blood cell (RBC) membrane N-glycans determine blood type and influence cell lifespan. Although several proteomic studies have been carried out, the glycosylation of RBC membrane proteins has not been systematically investigated. This work aims at exploring the human RBC N-glycome by high-sensitivity MALDI-MS techniques to outline a fingerprint of RBC N-glycans. To this purpose, the MALDI-TOF spectra of healthy subjects harboring different blood groups were acquired. Results showed the predominant occurrence of neutral and sialylated complex N-glycans with bisected N-acetylglucosamine and core- and/or antennary fucosylation. In the higher mass region, these species presented with multiple N-acetyllactosamine repeating units. Amongst the detected glycoforms, the presence of glycans bearing ABO(H) antigens allowed us to define a distinctive spectrum for each blood group. For the first time, advanced glycomic techniques have been applied to a comprehensive exploration of human RBC N-glycosylation, providing a new tool for the early detection of distinct glycome changes associated with disease conditions as well as for understanding the molecular recognition of pathogens.  相似文献   
709.
710.
In this paper, we are interested in answering the following research question: “Is it possible to form effective groups in virtual communities by exploiting trust information without significant overhead, similarly to real user communities?” In order to answer this question, instead of adopting the largely used approach of exploiting the opinions provided by all the users of the community (called global reputation), we propose to use a particular form of reputation, called local reputation. We also propose an algorithm for group formation able to implement the proposed procedure to form effective groups in virtual communities. Another interesting question is how to measure the effectiveness of groups in virtual communities. To this aim we introduce the \begin{document}$G_k$\end{document} index in a measure of the effectiveness of the group formation. We tested our algorithm by realizing some experimental trials on real data from the real world EPINIONS and CIAO communities, showing the significant advantages of our procedure w.r.t. another prominent approach based on traditional global reputation.  相似文献   
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