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1.
Nontuberculous mycobacteria are increasingly recognized as important pathogens in peritonitis associated with continuous ambulatory peritoneal dialysis (CAPD). Mycobacterium gordonae rarely causes human infection and is the least likely mycobacterium to produce clinical infection in CAPD patients. We describe a patient with persistent M. gordonae peritonitis acquired while undergoing CAPD. During 18 months of treatment, clinical improvement occurred but a microbiological cure could not be achieved. Principles of therapy for mycobacterial peritonitis developing during CAPD are reviewed, and potential explanations for our patient's failure to respond to therapy are discussed.  相似文献   
2.
The present study has been divided into two sets. In the first set, the aim of the experiments was to investigate the dose-response effect of selective serotonin re-uptake inhibitor (SSRI) citalopram on rat exploratory behaviour in the elevated plus-maze. In the second set of experiments, the effect of cholecystokinin (CCK) CCKA and CCKB receptor antagonists, devazepide and L 365260, on citalopram-induced decrease of exploratory behaviour in the elevated plus-maze was studied. Citalopram (5 and 10 mg/kg) decreased the number of open and total arm entries, line crossings on open arms, and percentage of time spent exploring in open arm. Dose 15 mg/kg was without any effect on rat exploratory behaviour. Devazepide (0.01 and 1.0 mg/kg) failed to modify any of the citalopram-induced changes observed. L 365260 (1.0 mg/kg) reversed most of the effects of citalopram: the numbers of open and total arm entries, the number of line crossings, and the percentage of time spent exploring in open arms. L 365260 at dose level 0.01 mg/kg was ineffective. These results support the involvement of the CCKB receptor subtype in SSRI-induced anxiogenic-like effects in rodents.  相似文献   
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The suppression of superconductivity of the first kind in a hollow cylindrical superconductor by a strong electric current is studied on the basis of the linear time-dependent Ginzburg-Landau equations. Due to the presence of an electric field, mixed state consisting of superconducting fluctuations is established at the inner surface of the sample close to some critical current. When the inner radiusr 1 of the cylinder is of the order of magnitude of the superconducting coherence length , the magnetic response to a longitudinal magnetic field H a shows an oscillatory dependence of the magnetic flux onr 1/ and H a due to the quantum character of the macroscopic wave function. In the limiting situationsr 1 andr 1=0 we find again the paramagnetic and diamagnetic effect of the two- and one-dimensional mixed states respectively.  相似文献   
5.
The thermodynamics of the mixed state of niobium is reconsidered. Critical fieldsH c (t),H c1(t),and H c2(t), Maki parameters 1 and 2, magnetization, and specific heat are measured with a computer-controlled magnetometer and calorimeter. The results show quantitative discrepancies with the isotropic Gorkov-Brandt theory over almost the whole mixed state. Computations based on Fermi surface anisotropy using a scaling ofH c2 provide a much better agreement with the experimental magnetization curves already in the limit of weak nonlocality, thus suggesting a numerical evaluation of the anisotropic terms in the Gorkov-Brandt theory.  相似文献   
6.
A key issue in crisis communication is the way people process crisis‐relevant information to minimize danger. This paper discusses the impact of previously experienced crises on the public's interpretation of warning messages. People may not have direct experience of a crisis, but they still have acquired mediated experiences of a variety of crises. The present study introduces the term cultural experience of crisis to label the synthesis of mediated crisis experiences, media and fictional narratives, collective memories of societal disasters, conversations, and immediate crisis experiences of witnesses and victims. The proposed model of cultural experience of crisis is elaborated on the basis of a qualitative text analysis derived from four qualitative interviews 16 focus groups interviews carried out in Estonia from 2008 to 2009.  相似文献   
7.
Cucumber plants (Cucumis sativus L.) respond to spider–mite (Tetranychus urticae) damage with the release of specific volatiles that are exploited by predatory mites, the natural enemies of the spider mites, to locate their prey. The production of volatiles also can be induced by exposing plants to the plant hormone jasmonic acid. We analyzed volatile emissions from 15 cucumber accessions upon herbivory by spider mites and upon exposure to jasmonic acid using gas chromatography—mass spectrometry. Upon induction, cucumber plants emitted over 24 different compounds, and the blend of induced volatiles consisted predominantly of terpenoids. The total amount of volatiles was higher in plants treated with jasmonic acid than in those infested with spider mites, with (E)-4,8-dimethyl-1,3,7-nonatriene, (E,E)-α-farnesene, and (E)-β-ocimene as the most abundant compounds in all accessions in both treatments. Significant variation among the accessions was found for the 24 major volatile compounds. The accessions differed strongly in total amount of volatiles emitted, and displayed very different odor profiles. Principal component analysis performed on the relative quantities of particular compounds within the blend revealed clusters of highly correlated volatiles, which is suggestive of common metabolic pathways. A number of cucumber accessions also were tested for their attractiveness to Phytoseiulus persimilis, a specialist predator of spider mites. Differences in the attraction of predatory mites by the various accessions correlated to differences in the individual chemical profiles of these accessions. The presence of genetic variation in induced plant volatile emission in cucumber shows that it is possible to breed for cucumber varieties that are more attractive to predatory mites and other biological control agents.  相似文献   
8.
A primal dual method of Kushner and Sanvicente for a constrained optimization problem with convex regression functions is investigated without a priori bounds. For the stochastic approximation sequence almost sure convergence to a random optimal solution and a random Kuhn-Tucker vector is shown, and for the uniqueness case, a functional central limit theorem is given.  相似文献   
9.
SiC and TiB2 were electrochemically coated with Cr2O3 from a 0.1 M aqueous solution of chromium nitrate hydrate with ethanol additives. On both substrate materials poly-crystalline Cr2O3 was formed at current densities from 5 to 50 mA/cm2 and deposition durations of 5 to 30 min. The coating weight increased with current density and with deposition time. The as-deposited coatings contained microcracks due to drying shrinkage. Microstructural observations indicate that sintering of the Cr2O3 coatings on TiB2 at 1100°C for 1 n in a reducing atmosphere in a closed graphite crucible causes the densification of the coating via a liquid phase, which forms by oxidation of TiB2. Under similar conditions, the Cr2O3 coatings on SiC may be sintered via an evaporation–condensation mechanism.  相似文献   
10.
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