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Green River oil shale was supercritically treated with methanol and water and then extracted with benzene and methanol to recover approximately 85% of the organic matter in the shale. The spent shale was then extracted with pyridine to recover an additional 2-31% of the organic matter that remained on the shale. The liquid organic material extracted with pyridine contained some of the compound types most difficult to recover from shale. These materials were characterized. High-molecular nitrogen compounds of the pyridine type were found to be a predominant compound class in the pyridine extract. The pyridine-extracted material contained a higher percentage of nitrogen than a Fischer assay oil and a lower percentage of hydrogen than a Fischer assay oil indicating that more aromatic nitrogen compounds were present in the pyridine extract than in Fischer assay oil. Bonding mechanisms between organic and inorganic components of the shale were studied as were spectroscopic data showing the nature of the organic material remaining on spent shale after extraction with pyridine. 相似文献
165.
Roles of Levies for Sustainable Domestic Water Consumption 总被引:1,自引:1,他引:0
Sustainable development is the modern rhetoric to guide environmental or natural resources management. There are many ways
to do this and one is the wider utilization of economic instruments, such as taxes and levies. Although such levies are becoming
common in Australia and worldwide, the role of the taxes or levies is still limited. In many cases, these taxes/levies -although
environmentally related- have a fiscal rather than a purely environmental motive, for example, the Natural Resources Management
(NRM) Levy in South Australia. This study evaluates the NRM levy policy using one NRM region and focussing on the Adelaide
urban community. Data was collected through a web-based survey with 770 respondents who answered 59 questions. The research
found that community strongly prefers a levy calculated on the volume of water consumed. Respondents also indicated that they
would use less water if the levy were calculated on the volume of water consumed. The clear implications of the results suggest
that if a tax or levy aims to change water consumption behaviour then it should be based on the volume of water consumed not
on property value. 相似文献
166.
Mensinger Janell Lynn; Lynch Kevin G.; TenHave Thomas R.; McKay James R. 《Canadian Metallurgical Quarterly》2007,75(5):775
A previous randomized trial with 224 alcohol and/or cocaine addicts who had completed an initial phase of treatment indicated that 12 weeks of telephone-based continuing care yielded higher abstinence rates over 24 months than did group counseling continuing care. The current study examined mediators of this treatment effect. Results suggested that self-help involvement during treatment and self-efficacy and commitment to abstinence 3 months after treatment mediated subsequent abstinence outcomes. These analyses controlled for substance use prior to the assessment of mediators. Conversely, there was no evidence that self-help beliefs or social support mediated the treatment effect. These results are consistent with a model in which treatment effects are first accounted for by changes in behavior, followed by changes in self-efficacy and in commitment to abstinence. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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A M McKay 《International journal of food microbiology》1992,15(3-4):383-388
Permeation of oxygen through polystyrene packaging is a factor in the growth of yeasts in natural yoghurt. Diffusion of oxygen through the packaging material can permit the growth of non-fermentative yeasts in yoghurt stored at refrigeration temperatures. Yarrowia lipolytica, a non-fermentative yeasts which does not utilize lactose was isolated from yoghurt. The growth in natural yoghurt of Yarrowia lipolytica and the lactose-fermenting yeast Kluyveromyces marxianus was investigated. Both yeasts grew in yoghurt with reduced fat content. Storage of yoghurt in an anaerobic atmosphere eliminated growth of Yarrowia lipolytica but permitted fermentative growth of Kluyveromyces marxianus. 相似文献
170.
Efficacy of high-dose glycine in the treatment of enduring negative symptoms of schizophrenia 总被引:1,自引:0,他引:1
U Heresco-Levy DC Javitt M Ermilov C Mordel G Silipo M Lichtenstein 《Canadian Metallurgical Quarterly》1999,56(1):29-36
PURPOSE: To assess the effectiveness and safety of self-expanding metallic stents as a primary palliative treatment for inoperable malignant colorectal strictures. METHODS: Under radiological guidance 20 self-expanding metallic Wallstents were implanted in 16 consecutive patients with colorectal stenoses caused by malignant neoplasms, when surgical treatment of the condition had been ruled out. The patients were followed up clinically for 1-44 months, until death or termination of this study. RESULTS: The stents were successfully implanted in all cases and resolved the clinical obstruction in all the patients except one, who underwent subsequent colostomy. During follow-up of the remaining 15 patients, clinical complications arising from the procedure were pain (two patients), minor rectal bleeding (one patient), and severe rectal bleeding (one patient) (26%). There were three cases of stent migration and three cases of stent occlusion, and reintervention by us was necessary in 20% of cases (3/15). The mean life span following the procedure was 130 days, and none of the patients exhibited clinical symptoms of obstruction at the time of death (12 patients) or termination of the study (3 patients). CONCLUSION: Deployment of metallic stents under radiologic guidance is an effective alternative as a primary palliative measure in malignant colorectal obstruction, though the possible clinical complications and need for repeat intervention during follow-up should be taken into account. 相似文献