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The growth of Sb nanowires on GaSb(111)A substrates is studied by in?situ azimuthal scan reflection high-energy electron diffraction (ARHEED). Bulk and layer contributions can be distinguished in the ARHEED transmission pattern through the Sb nanowires. The three-dimensional structure of the growing Sb nanowires is identified by post-growth atomic force microscopy (AFM) and x-ray diffraction (XRD). The lattice match of the Sb crystal along the [Formula: see text] and the GaSb crystal along [Formula: see text] directions lead to a preferential orientation of the Sb nanowires. The Sb adsorption and desorption kinetics is studied by thermal desorption spectroscopy.  相似文献   
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This paper presents ongoing research into using Artificial Intelligence (AI) techniques to intelligently control finite element thermal analyses. These techniques are used to implement component level decomposition of the physical domain, and to integrate domain information into the analysis process to increase computational efficiency. We have implemented these techniques into a new proof-of-concept finite element program which employs a blackboard architecture to integrate the various numerical and symbolic knowledge sources. The blackboard architecture also supports the storage (and retrieval) of data in an object-oriented form. A test problem involving transient thermal analysis of an integrated circuit package is presented. Use of the proposed method showed a significant decrease in the number of floating point operations required compared to conventional solution technologies. The penalty associated with this saving was approximately a 4% difference in the calculated temperature in the critical region of interest.  相似文献   
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Motivational attunement is presented here as a set of guiding principles that can be used to foster the therapeutic alliance in cognitive-behavioral therapy (CBT). The overarching goal of motivational attunement is to provide the client with need-satisfying experiences. In order to do so, the therapist must attune his or her interventions to the client's motivational goals. The authors attempt to demonstrate how therapists can assess motivational goals and use this information to foster the central components of the alliance. The authors also outline how motivational attunement can be used to prevent and resolve alliance ruptures. Finally, empirical support for the effects of motivational attunement is briefly described. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The fast and non-destructive character of neutron radiography provides the possibility of in-situ investigations of hydrogen uptake and diffusion in zirconium alloys. A special reaction furnace with neutron transparent windows was constructed. The method of quantitative hydrogen determination by neutron transmission measurements was calibrated for each experimental run. Additionally, oxygen is absorbed in the α-Zr phase and precipitated in the oxide layer. The calibration of the correlation between hydrogen and oxygen concentrations and total neutron cross-sections at room temperature and between 1123 and 1623 K are described.Results of in-situ neutron radiography investigations of hydrogen diffusion and absorption are presented in this paper. A linear dependence of the total macroscopic neutron cross section on the H/Zr atomic ratio as well as on the oxygen concentration was found. No significant temperature dependence of the total neutron cross-sections of hydrogen dissolved in β-Zr or oxygen dissolved in the α-Zr or precipitated in the oxide layer was found.  相似文献   
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Cryptococcosis is an epidemiological and immunological indicator due to the absence of Cryptococcus neoformans as a saprophyte in immunocompetent humans and the advantage of specific C. neoformans culture. On this basis, a report is presented on the CD4 lymphocyte count of 36 AIDS patients suffering from cryptococcosis and other concomitant or missing opportunistic AIDS-defining infections. In 26 out of 36 patients, i.e. 72%, a CD4 lymphocyte count of < or = 50/microL (mean value 39.5%) was found. Cryptococcosis as the sole opportunistic infection was diagnosed in 5 cases (13.9%). In 31 cases, various combinations of AIDS-associated diseases were found: Pneumocystis carinii pneumonia (PCP) (n = 19), cytomegalovirus infection (CMV) (n = 10), Kaposi's sarcoma (n = 6), Mycobacterium avium intracellulare infection (MAI) (n = 5), pneumonia (n = 2), toxoplasmosis (n = 2), Candida esophagitis (n = 1), tuberculosis (n = 1), lambliasis (n = 1), salmonellosis (n = 1) and wasting syndrome (n = 5). The conspicuous simultaneous occurrence or succession of pneumocystosis and cryptococcosis and the contrasting absence of aspergillosis and mucormycosis (zygomycosis) are commented. Based on the present observations in HIV-infected persons in Berlin, a CD4 lymphocyte count of < 150/microL may be used as a parameter indicating a predisposition for cryptococcosis as an airborne AIDS-defining infection. Attention is drawn to bird droppings as the sole habitat of C. neoformans and accidental niche of various other microorganisms.  相似文献   
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Male and female B6C3F1 mice from 12 National Toxicology Program (NTP) 2-yr carcinogenesis studies were found to be infected with Helicobacter hepaticus. Many of the male mice from 9 of these studies had an associated hepatitis (affected studies). Helicobacter hepaticus has been reported to be associated with an increased incidence of hepatitis and hepatocellular neoplasms in the A/JCr male mouse. We attempted to determine if the data from the Helicobacter-affected NTP B6C3F1 mouse studies were compromised and unsuitable for cancer hazard identification. The incidences of neoplasms of the liver (both hepatocellular and hemangiosarcoma) but not of other organs in control male B6C3F1 mice were increased in affected studies as compared with control males from unaffected studies. The increased incidence of hepatocellular neoplasms was observed in those males exhibiting H. hepaticus-associated hepatitis. Other observations further differentiated control male mice from affected and unaffected studies. H-ras codon 61 CAA to AAA mutations were less common in liver neoplasms from males from affected studies as compared with historical and study controls. In addition, increases in cell proliferation rates and apoptosis were observed in the livers of male mice with H. hepaticus-associated hepatitis. These data support the hypothesis that the increased incidence of liver neoplasms is associated with H. hepaticus and that hepatitis may be important in the pathogenesis. Therefore, interpretation of carcinogenic effects in the liver of B6C3F1 mice may be confounded if there is H. hepaticus-associated hepatitis.  相似文献   
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