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161.
A new BIST scheme for on-chip testing of non-volatile memories and based on signature analysis is presented. The signature of the whole memory, whose content can be changed selectively by the user, is dynamically self-learned by the memory and it is saved in a dedicated memory location. Either such a signature can be externally compared with the expected one in order to check for the programming operation, or it can be used for comparison purposes when data retention must be self-tested.  相似文献   
162.
The present work develops the processing and abrasive tests of composites based on the system epoxy–quartz. The objective was to evaluate its technological application as abrasive crowns for the polishing of ornamental rocks, usually made based on the magnesia cement composite SOREL-SiC. Composites were produced with composition epoxy–(70, 75, 80, 85 and 90) % weight of quartz. The compounds were mixed and cured with a catalyst. The composites were submitted to abrasive wearing tests and compressive tests, simulating the polishing operation of ornamental rocks. Surface finishing produced in an ornamental rock and the weight loss of the crowns were evaluated and compared to those obtained for commercial magnesia cement SOREL-SiC. The work concludes for the positive technical viability of this new composite epoxy-silica for use in the ornamental rock industry.  相似文献   
163.
The aim of the experiments performed in this work was to develop a biofilm airlift suspension (BAS) process for the degradation of a mixture of organic sulfonates contained in the infiltration water from a contaminated site. To achieve this goal, active biomass growing on the contaminating xenobiotic organics as the sole source of carbon was obtained by enriching a mixed microbial culture sampled from an activated sludge treatment plant. After kinetic characterisation, the enriched culture was inoculated in the BAS reactor, where it colonised carrier particles and formed stable and uniform biofilms. In spite of the slow growth and degradation kinetics (mu(max)=0.014 h(-1)), due to high biomass concentration (up to 12 g(VS)L(-1)) a high rate process was performed in the BAS reactor, achieving a degradation capacity of 8.7 kg(COD)m(-3)d(-1), with an overall degradation efficiency of 70% based on COD measurements.  相似文献   
164.
The hibernating golden hamster (Mesocricetus auratus) is becoming a useful rodent model to study the neurophysiological role of some neuromediators on vital behaviors such as sleep and thermoregulation. Recent works have shown that the histamine neuroreceptor subtypes (H1-3R) are able to modulate such behaviors. Here, specific subtype(s) and cerebral nuclei that were actively operating on feeding behaviors in pubertal and adult hamsters were identified. Of the subtypes assessed, H?R antagonist (thioperamide) provoked significant ( p  相似文献   
165.
Monumental buildings are by definition unique buildings that cannot be reduced to any standard structural scheme: this makes it difficult to evaluate their seismic reliability, because—in addition to the many uncertainties that are common to all existing (and in particular “old”) buildings—no statistics on the behaviour of similar buildings can be available. To overcome this problem, the macroelement approach has been proposed a few years ago and since then repeatedly used to analyse and compare the seismic response of monumental buildings: the structural organism is considered as the assemblage of few components (e.g. the whole façade of a church) whose behaviour is typical of the behaviour of analogous macroelements in other buildings, and whose possible collapse mechanisms can be identified. In these studies, quasi-static loads have been used, as indeed common in many analyses of the seismic behaviour of masonry structures. This paper accepts these simplifying assumptions, and shows how—assuming appropriate probabilistic properties of the relevant quantities and a “logical diagram” describing the relation between collapse of macroelements and whole building—the probability of collapse and damage of each macroelement and of the whole building under given horizontal loads can be assessed. The procedure is formulated in detail with special reference to churches, and illustrated on two example cases. The same procedure can be used as the basis of a statistical extrapolation aimed at evaluating the probability distributions of collapse and damage among monumental buildings that are similar with regard to both the macroelement typologies and the logical diagram.  相似文献   
166.
This paper presents an industrial case study relevant to a fuzzy logic controller designed via a properly developed genetic algorithm. We consider an example of a fuzzy logic‐based industrial process‐controller. In particular, we deal with the problem of controlling the speed of a belt conveyor for glass containers in a bottling plant. The primary objective of the controller is to guarantee the continuous feed to the filling station, in the presence of frequent gaps between bottles. The secondary objective is to reduce the impact speed between arriving bottles and those standing in the queue, in order to reduce the plant noise. High‐performance parameters of the fuzzy controller are found by a properly developed genetic algorithm. The results provided by Monte Carlo simulations demonstrate that, with such controllers, it is possible to achieve both the objectives mentioned above. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
167.
This paper presents a protection structure built for a bridge pier consisting of six narrow piles. Accumulation of large woody debris upstream of the pile group during high-flow terms might have induced much larger scour depths compared with those expected for the single pile. A phenomenological sketch of the system suggested that accumulation of debris material during peak flows and subsequent descent of the same material during the tail of the events represented a very dangerous two-stage process owing to the high expected scour. Consequently, a countermeasure was designed, consisting of a plate preventing the descent of debris below its elevation. The performance of the plate in reducing local scour was subjected to some preliminary laboratory tests, and satisfactory results were obtained. This paper reports some tentative performance observations for the real structure built on the river, based on the amount of debris trapped during a recent event with moderate flow.  相似文献   
168.
Manufacturing companies are continuously facing the challenge of operating their manufacturing processes and systems in order to deliver the required production rates of high quality products, while minimizing the use of resources. Production quality is proposed in this paper as a new paradigm aiming at going beyond traditional six-sigma approaches. This new paradigm is extremely relevant in technology intensive and emerging strategic manufacturing sectors, such as aeronautics, automotive, energy, medical technology, micro-manufacturing, electronics and mechatronics. Traditional six-sigma techniques show strong limitations in highly changeable production contexts, characterized by small batch productions, customized, or even one-of-a-kind products, and in-line product inspections. Innovative and integrated quality, production logistics and maintenance design, management and control methods as well as advanced technological enablers have a key role to achieve the overall production quality goal. This paper revises problems, methods and tools to support this paradigm and highlights the main challenges and opportunities for manufacturing industries in this context.  相似文献   
169.
Triple-negative breast cancer (TNBC) is an aggressive breast tumor subtype characterized by poor clinical outcome. In recent years, numerous advancements have been made to better understand the biological landscape of TNBC, though appropriate targets still remain to be determined. In the present study, we have determined that the expression levels of FGF2 and S100A4 are higher in TNBC with respect to non-TNBC patients when analyzing “The Invasive Breast Cancer Cohort of The Cancer Genome Atlas” (TCGA) dataset. In addition, we have found that the gene expression of FGF2 is positively correlated with S100A4 in TNBC samples. Performing quantitative PCR, Western blot, CRISPR/Cas9 genome editing, promoter studies, immunofluorescence analysis, subcellular fractionation studies, and ChIP assays, we have also demonstrated that FGF2 induces in TNBC cells the upregulation and secretion of S100A4 via FGFR1, along with the ERK1/2–AKT–c-Rel transduction signaling. Using conditioned medium from TNBC cells stimulated with FGF2, we have also ascertained that the paracrine activation of the S100A4/RAGE pathway triggers angiogenic effects in vascular endothelial cells (HUVECs) and promotes the migration of cancer-associated fibroblasts (CAFs). Collectively, our data provide novel insights into the action of the FGF2/FGFR1 axis through S100A4 toward stimulatory effects elicited in TNBC cells.  相似文献   
170.
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