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The open source approach to software development has been used by software organizations in tandem with their existing business models, which are based on proprietary software licensing. This led to the creation of hybrid business models that merge open source and proprietary paradigms. This paper explores the practices used by software product vendors using hybrid business models and proposes strategies emerging out of these practices using interpretive, single case study research design.  相似文献   
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From 2002 to 2007, more than 400,000 photovoltaic (PV) solar home systems (SHS) were sold in northwestern China under the US$316 million World Bank/Global Environment Facility-supported Renewable Energy Development Project (REDP). REDP has been hailed as a best practice example in SHS deployment for its unprecedented scale and the combination of technology improvement and market development support components to strengthen the country’s renewable energy industry. While the World Bank has itself conducted post-project evaluations, our paper presents the first independent review with the intent of determining if anticipated project impacts have been sustained. We adopt a case study format supported by in-depth interviews with the project’s relevant stakeholder groups and find that solar home systems (SHS) provide monetary and non-monetary benefits to users and that their portability complements the lifestyle of the region’s nomadic herders. However, we also find that purchasing decisions are still based on price more than quality, after-sales service networks remain weak, and households in REDP’s coverage area are gradually gaining access to hydropower-based grid electricity.  相似文献   
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Judging by WHO criteria, there was not a single case in India in 1994 that could be taken as a confirmed case of plague. Both clinical and epidemiological features of the illness alleged to be plague were not at all compatible with those of plague-both bubonic and pneumonic types. The bacteriologic and serological evidence was limited to a few cases, and doubtful. PCR is a highly sensitive test, but the specificity of PCR for plague was not verified under field conditions in India. Just by the demonstration of the presence of a causative organism in the environment or in the body tissue, one cannot substantiate occurrence of an infection or disease in man. In view of the assessment and review presented in this paper, one can conclude that the outbreaks of illness that resembled plague during late 1994 in Beed District and Surat were certainly not due to plague. If the Mamla outbreak had not been declared to be plague, the probability of the Surat illness being labeled as plague was negligible. Whatever happened provides a very important lesson of the harm that can occur nationally and globally from decisions based on inadequate or incorrect information.  相似文献   
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Natural polysaccharides like chitosan and dextran have garnered considerable interest in biomedical applications due to their biocompatibility, biodegradability, and nontoxicity. Nonetheless, the development of a reproducible class of medical devices from these materials is challenging and has had limited success. Chitosan and dextran are inherently variable and synthesis using these materials is prone to inconsistencies. In this study, we put forward a robust product development regimen that allows these natural materials to be developed into a reproducible class of biomaterials. First, an array of validated characterization methods (Proton Nuclear Magnetic Resonance, titrations, Ultraviolet spectroscopy, Size Exclusion Chromatography—Multi-Angle Light Scattering, Size Exclusion Chromatography—Refractive Index, and proprietary methods) were developed that allowed rigorous specifications to be set for unprocessed chitosan and dextran, chitosan and dextran intermediates, and chemically modified materials—acrylated chitosan (aCHN) and oxidized dextran (oDEX). Second, a robust and reproducible synthesis scheme involving various in-process controls was developed to chemically modify the unprocessed polysaccharides. Third, purification methods to remove byproducts and low-molecular-weight impurities for both aCHN and oDEX were developed. The study presents a viable strategy for converting variable, natural materials into a reproducible class of biomaterials that can be applied in various biomedical applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48454.  相似文献   
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For better blast furnace performance, there has always been a need for better quality raw materials like sinter, lump ore, and pellets. Among these raw materials the usage of sinter in blast furnace is at higher side compared to other iron bearing materials. As the quality of sinter product improves, its usage in blast furnaces also increases. Iron ore fines are the main source for sinter making. To improve the sinter properties it is necessary to provide good quality of iron ore fines. Due to depletion of high grade iron ore resources, goethite and limonitic ore content in iron ore fines is expected to increase gradually. Usually limonitic and goethite ore are associated with higher alumina and LOI. The conventional sintering process is one of the well established processes for high quality hematite ore. It does not fully respond to the low grade iron ore associated with goethite and limonite. This has led to deterioration in sinter properties and productivity. In recent years the improvement in the quasi‐particle structure with the granulation process is an effective method for improving sinter quality and productivity. To improve the sinter quality and productivity for low grade iron ore fines, different granulation processes like the conventional one, and other two advanced granulation processes like coke breeze, and flux & coke breeze coating granulation were studied in detail by conducting laboratory pot grate sintering experiments. From the test results it was found that sinter productivity, physical and metallurgical properties of the sinter improved with flux & coke breeze coating granulation process compared to conventional and coke breeze coating granulation process. Proper selection of the granulation time is very important to achieve the desired sinter properties. In the present work detailed laboratory experiments have been carried out by varying the coating time from 30s to 110s to study the influence of flux & coke breeze coating granulation time on mineralogy, productivity, physical, and metallurgical properties of sinter. With a coating granulation time of 50s, higher productivity, higher yield, and stronger sinter (higher T.I) with lower RDI and ‐5mm size sinter were achieved.  相似文献   
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The article explores the energy security concerns faced by China from the point of view of energy users working in government, university, civil society and business sectors. The authors first derive a set of seven hypotheses related to Chinese energy security drawn from a review of the recent academic literature. We then explain each of these seven hypotheses, relating to (1) security of energy supply, (2) geopolitics, (3) climate change, (4) decentralization, (5) energy efficiency, (6) research and innovation of new energy technologies, and (7) self sufficiency and trade. Lastly, the article tests these hypotheses through a survey distributed in English and Mandarin completed by 312 Chinese participants. The conclusion presents insights for policymakers and energy scholars.  相似文献   
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BACKGROUND: Iron and iodine deficiencies affect more than 30% of the world's population. Typical Indian diets contain adequate amounts of iron, but the bioavailability is poor. This serious limiting factor is caused by low intake of meat products rich in heme iron and intake of phytates in staple foods in the Indian diet, which inhibits iron absorption. OBJECTIVE: To test the stability of double-fortified salt (DFS) during storage and to assess its efficacy in improving the iron and iodine status of the communities. METHODS: The stability of both iodized salt and DFS during storage for a 2-year period was determined. The bioefficacy of DFS was assessed in communities covering three states of the country for a period of 1 year. This was a multicenter, single-blind trial covering seven clusters. The experimental group used DFS and the control group used iodized salt. The salts were used in all meals prepared for family members, but determination of hemoglobin by the cyanmethemoglobin method was performed in only two or three members per family, and not in children under 10 years of age (n = 393 and 436 in the experimental and control groups, respectively). The family size was usually four or five, with a male: female ratio of 1:1, consisting of two parents with two or three children. Hemoglobin was measured at baseline, 6 months (midpoint), and 12 months (endpoint). Urinary iodine was measured in only one cluster at baseline and endpoint. All the participants were dewormed at baseline, 6 months, and 12 months. RESULTS: The iron and iodine in the DFS were stable during storage for 2 years. Over a period of 1 year, there was an increase of 1.98 g/dL of hemoglobin in the experimental group and 0.77 g/dL of hemoglobin in the control group; the latter increase may have been due to deworming. The median urinary iodine changed from 200 microg/dL at baseline to 205 microg/dL at the end of the study in the experimental group and from 225 microg/dL to 220 microg/dL in the control group. There was a statistically significant (p < .05) improvement in the median urinary iodine status of subjects who were iodine deficient (urinary iodine < 100 microg/L) in both the experimental and the control groups, a result showing that DFS was as efficient as iodized salt in increasing urinary iodine from a deficient to sufficient status. There was a statistically significant increase (p < .05) in hemoglobin in all seven clusters in the experimental group compared with the control. CONCLUSIONS: The iron and iodine in the DFS are stable in storage for 2 years. The DFS has proved beneficial in the delivery of bioavailable iron and iodine.  相似文献   
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Arachidonic acid is suggested to play a role in the expression of long-term potentiation (LTP), a synaptic analog of memory and learning. However, it is unknown whether this free fatty acid is actually released during LTP or not. To address this question, we assayed arachidonic acid with an HPLC system using 9-anthryldiazomethane (ADAM) as a fluorescent probe. High frequency stimulation (tetanic stimulation) to a hippocampal slice from the guinea pig brain caused a huge increase in the release of glutamate from presynaptic terminals and in turn, a gradual increase in the release of arachidonic acid. A similar increase in the release of arachidonic acid was induced by application of glutamate and the increase was inhibited by either the selective AMPA/kainate receptor antagonist, DNQX, or to a lesser extent by the selective NMDA receptor antagonist, APV. These findings suggest that arachidonic acid is produced by activation of ionotropic glutamate receptors involving expression of LTP. Arachidonic acid exerted a long-lasting facilitatory action on synaptic transmission in the CA1 region of rat hippocampal slices and the facilitation occluded the tetanic LTP. Arachidonic acid, thus, appears to be a significant factor for the expression of LTP.  相似文献   
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