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21.
Lung adenocarcinoma is the most common cell type in females (smokers or non-smokers) and in non-smoking males. Its incidence has been increasing in younger cohorts of males and females until very recent years. Changes in classification and in pathological techniques account for some of this increase. In females and non-smoker males, the increase could be partly due to a detection bias in former studies. Nevertheless, successive cohorts over time seem more likely to develop adenocarcinoma and less likely to develop squamous cell carcinoma. These differences between birth cohorts suggest that the increasing incidence of adenocarcinoma is not only due to changes in pathological diagnosis. Geographical differences are also observed: in Europe, the squamous cell type still predominates and an increase in incidence of adenocarcinoma has only been reported in the Netherlands. In Asia, in the 1960s and 1970s, the proportion of adenocarcinoma was higher than in North America or Europe and seems to be increasing. To what extent these differences are due to differences. In establishing diagnosis remains unknown. Despite these biases in temporal and geographical trends detailed in this review, there has probably been a true increase in incidence of adenocarcinoma. An explanation for this should be sought in studies on detailed smoking history and passive smoking exposure, occupational exposure, diet and cooking, pollution and other environmental factors.  相似文献   
22.
The effects of a NK1 antagonist, GR205171, and a 5-HT3 antagonist, ondansetron, in a novel model of post-anaesthesia-induced emesis in Suncus murinus is described. GR205171 (1 and 3 mg k(-1) s.c) and ondansetron (3 mg kg(-1) s.c.) each significantly inhibited emesis. This model may be useful for studying drugs to treat post-operative nausea and vomiting in man.  相似文献   
23.
The modeling and optimal flow control of a Jacksonian network in equilibrium is investigated. The model employed consists of a controller node cascaded with the Jacksonian network. Input packets arrive at the controller node with a Poissonian rate δ. For a blocking type strategy for accessing the network it is shown that the control which maximizes the average throughput of the network subject to a bounded average time delay constraint is a window flow control mechansim. The window size depends on the offered load δ, the maximum service rate of the controlling queueing system, c, and the Norton equivalent service rate of the network μ. The dependence of the average throughput and the average time delay on the control is also analyzed.  相似文献   
24.
In this article, poly(vinyl chloride) (PVC) sandwich‐structured hybrid composites with amorphous calcium carbonate and wood‐filled cores were obtained by compression molding. It has been determined that wood addition up to a weight ratio of 33% reported to the total filler amount is beneficial in improving both the inter‐filler and filler‐matrix interfacial adhesion, which alongside with the promoting of the amorphous PVC matrix crystallization is responsible for an increase up to 34% in the flexural strength of the composites, compared to unfilled PVC. The hybrid filled composites present up to 35% lower friction coefficients and up to 20% higher Brinell hardness values than the composites filled with calcium carbonate alone. Subsequently, wood addition determines an increase in the oxidation onset temperature for PVC and an increase with up to 20% in the sound and thermal‐insulative properties of the composites, compared to unfilled PVC. The dominating dispersive part of the composites surface energy aids in improving the mass and dimensional stability of the assembly to both water and dilute hydrochloric acid aqueous solutions. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46317.  相似文献   
25.
The study presents the effects of different calcination temperatures on the size and morphology of mixed Co‐Ni ferrites, and the respective changes in the magnetic and electrical properties, with emphasis on their applicability as humidity sensors. The data suggests that the heat treatment does not significantly change the magnetic properties, but significant variations on the morphology of the nanoparticles, correlated with large changes in the electrical properties of the nanoparticles in terms of electrical permittivity and resistivity with electrical field frequency and humidity, with a clear influence of the calcination temperature over the sensibility of the materials to humidity.  相似文献   
26.
Sparse representations provide a powerful framework for various image processing tasks, among which image recovery seems to be an already classical application. While most developments of image recovery applications are focused on finding the best dictionary, the possibility of using already existing sparse image representations tends to be ignored. This is the case of the JPEG compressed image representation, which is a sparse image representation in terms of the discrete cosine transform (DCT) dictionary. The development of sparse frameworks directly on the JPEG encoded image representation can lead to computationally efficient approaches. Here we introduce a DCT-based JPEG compressed domain formulation of the color image recovery process within a sparse representation framework and we prove mathematically and experimentally not only its numerical efficiency as compared to the pixel level formulation (the processing time is reduced up to 40 %), but also the good quality of the restoration results.  相似文献   
27.
We present a tailored load balancing technique that addresses specific performance issues in the boundary data accumulation algorithm for non-overlapping domain decompositions. The technique is used to speed up a parallel conjugate gradient algorithm with an algebraic multigrid preconditioner to solve a potential problem on an unstructured tetrahedral finite element mesh. The optimized accumulation algorithm significantly improves the performance of the parallel solver and we show up to 50 % runtime improvements over the standard approach in benchmark runs with up to 48 MPI processes. The load balancing problem itself is a global optimization problem that is solved approximately by local optimization algorithms in parallel that require no communication during the optimization process.  相似文献   
28.
The present paper aims to investigate the electrodeposition on steel substrate and the corrosion behavior of Zn–TiO2 nanocomposite coatings. Zn–TiO2 composite coatings were electrodeposited on OL 37 steel from an electrolyte containing ZnCl2, KCl, HBO3 (pH 5.7) brightening agents and dispersed nanosized TiO2. Corrosion measurements were performed in 0.2 g L−1 (NH4)2SO4 solution (pH 3) by using electrochemical methods (open-circuit potential measurements, polarization curves, electrochemical impedance spectroscopy). The results of electrochemical measurements were corroborated with those obtained by using non-electrochemical methods (X-ray diffraction, atomic force microscopy and scanning electron microscopy). The results indicate that the composite coatings exhibit higher corrosion resistance as compared to pure Zn coatings and a non-linear dependence of their polarization resistance on TiO2 concentration in the plating bath was found. The importance of TiO2 nature and concentration regarding the properties of the composite coatings was demonstrated.  相似文献   
29.
Polyethers based on bis(2-chloroethyl) ether and various bisphenols were obtained using a phase transfer catalysis technique in a liquid/liquid system. 4,4′-Dihydroxyazobenzene, 4,4′-dihydroxybiphenyl, bisphenol A, 2,7-dihydroxynaphthalene and 4,4′-dihydroxydiphenyl) sulfide were used. Only the polymers with azobenzene and biphenyl units exhibited mesophases, since the others have semi-crystalline or amorphous structures. The polymers were characterized by 1H NMR, DSC and optical microscopy in polarized light. The molecular weights of the samples were low, situated in the oligomeric domain. The various transfer rates of the bisphenols from the aqueous to the organic phase, in some cases, led to very different copolymerization ratios as compared to the feed ratios. The LC polymers exhibited monotropic mesophases, probably for conformational reasons. A comparison between similar polyether structures containing the diethyletheric spacer and an oxetanic one was effectuated.  相似文献   
30.
Prognosis after myocardial infarction (MI) varies greatly depending on the extent of damaged area and the management of biological processes during recovery. Reportedly, the inhibition of the pro-inflammatory S100A9 reduces myocardial damage after MI. We hypothesize that a S100A9 blockade induces changes of major signaling pathways implicated in post-MI healing. Mass spectrometry-based proteomics and gene analyses of infarcted mice left ventricle were performed. The S100A9 blocker (ABR-23890) was given for 3 days after coronary ligation. At 3 and 7 days post-MI, ventricle samples were analyzed versus control and Sham-operated mice. Blockade of S100A9 modulated the expressed proteins involved in five biological processes: leukocyte cell–cell adhesion, regulation of the muscle cell apoptotic process, regulation of the intrinsic apoptotic signaling pathway, sarcomere organization and cardiac muscle hypertrophy. The blocker induced regulation of 36 proteins interacting with or targeted by the cellular tumor antigen p53, prevented myocardial compensatory hypertrophy, and reduced cardiac markers of post-ischemic stress. The blockade effect was prominent at day 7 post-MI when the quantitative features of the ventricle proteome were closer to controls. Blockade of S100A9 restores key biological processes altered post-MI. These processes could be valuable new pharmacological targets for the treatment of ischemic heart. Mass spectrometry data are available via ProteomeXchange with identifier PXD033683.  相似文献   
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