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141.
Influence of inulin on physical characteristics and staling rate of gluten-free bread 总被引:2,自引:0,他引:2
Inulin preparations with different degree of polymerization (HSI with a DP < 10, GR − DP ? 10 and HPX − DP > 23) were used for the production of gluten-free bread. It was found that an addition of investigated compounds resulted in an increase of loaf volume and reduction of crumb hardness. However, internal structure of the obtained loaves was less uniform and more open than in control bread. Generally, inulin preparations with lower degree of polymerization had stronger effect on all analyzed parameters than that with higher DP. A decrease in staling was observed (measured as the rate of crumb hardening), which was caused by the presence of inulin. The highest content of retrograded amylopectin was found for crumb with HSI, and the lowest for samples with HPX. 相似文献
142.
Potatoes are the world’s third largest food crop and the most extensively consumed root vegetable. They have high starch content and are a major source of dietary carbohydrate in human nutrition. This review article considers potatoes as a food crop, the properties of potato starch, and methods of preparing potatoes domestically for consumption, before considering the effects of potatoes on postprandial glycemia. Potatoes have been classified as a food that causes high postprandial glycemia, which over the long term may increase the risk of obesity and chronic diseases such as type-2 diabetes and cardiovascular disease. Methods for measuring the glycemic effects of potatoes are considered. In vivo methods, such as the glycemic index are discussed and compared with in vitro tests that measure the breakdown of available carbohydrates in potatoes. The potential for developing potato varieties that have more slowly-digestible starch, and hence a lower glycemic effect, is considered. 相似文献
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With the development of a knowledge economy, it is reasonable to assume that the level of innovation should be particularly high and that it should have a major effect on investment and productivity across all sectors, including the construction industry. For a valid assessment of the economic performance of the construction sector in terms of its productivity, it is important that the economic benefits for the sector from technological change are properly recognized but the impact of such benefits may be ‘hidden’ due to measurement issues, as innovative activity and investment in intangible assets have both gone unrecognized in official statistics. Much of the innovation in the construction sector is hidden from conventional measures and, for the UK economy, there is evidence that investment in intangibles may be even greater than tangible investment, if a definition of intangible assets incorporating spending on a broad range of knowledge‐based assets including organizational capital, human capital, etc. is taken. While accurate data are difficult to determine, an appraisal of the potential for utilizing existing data sources and for improved measurement is presented. 相似文献
145.
Les Bennett Joeol Le Calvez David R. 《国外测井技术》2007,22(4):53-67
深入了解水力压裂裂缝的几何形态和延伸情况有助于改善低渗油气藏压裂增产作业效果,改善油气井产能并提高油气采收率。应用地震方法对水力压裂裂缝进行监测和描述已经有多年了,而新的地震硬件和处理技术的出现使得这类监测更加有效、可靠。 相似文献
146.
Assessing stream condition is a foundation of adaptive management. But, summarizing stream condition in ways that smooth over the variance that is inherent within a watershed may lead to erroneous conclusions about its condition. This study compared stream condition summarized at a variety of spatial scales from segments to tertiary watersheds in order to evaluate the effect of summarization procedures on map interpretation. Sites were classified as to their degree of impairment from a reference state; a rank sum approach based on the length of stream sampled and simple scoring criteria (e.g., scores < 50 = F) was used to grade each reporting area. This study determined that scaling effects, choice of mapping thresholds and the size of reporting areas all affect the interpretation of results. Larger reporting areas were generally ranked lower; the source of this tendency is that larger stream segments are generally in a more degraded condition. There was a good correlation between predicted and observed stream segment condition, which indicates that the segment scale is the most reliable and informative of the reporting units tested. Providing categorized site conditions and confidence rankings on all larger scale maps offers a partial solution to these challenges. Where multiple sites collected on one segment were available, dramatic changes in condition indicate potential areas for restoration. This study confirmed the incremental nature of stream degradation associated with intensive land use, and demonstrated how inclusion of anything but the smallest units of stream area and confidence rankings in the results can generate biased interpretations of stream condition. 相似文献
147.
Hengyun Ma Les Oxley John Gibson Bonggeun Kim 《Environmental Modelling & Software》2009,24(11):1293-1301
China's demand for energy has grown to fuel its rapidly expanding industrial, commercial and consumer sectors. At the same time, China has become the second largest consumer of petroleum products having surpassed Japan for the first time in 2003. The environmental consequences of a continuation of these trends will have global implications. Government policies and consumers have become more environmentally aware, but the ability of governments to formulate policies has been hindered by the lack of data on inter-factor and inter-fuel substitution possibilities. In this paper Allen partial elasticities of factor and energy substitution, and price elasticities of energy demand are calculated for China's industrial economy using a two-stage translog cost function approach for the period 1995–2004. The results suggest that energy is substitutable with both capital and labor. Coal is significantly substitutable with electricity and slightly complementary with oil, while oil and electricity are slightly substitutable. China's energy intensity is increasing during the study period and the major driver appears to be due to the increased use of energy-intensive technology. 相似文献
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Z Mallat T Nakamura J Ohan G Lesèche A Tedgui J Maclouf RC Murphy 《Canadian Metallurgical Quarterly》1999,103(3):421-427
Evidence for increased oxidant stress has been reported in human atherosclerosis. However, no information is available about the importance of in situ oxidant stress in relation to plaque stability. This information is relevant because the morbidity and mortality of atherosclerosis are essentially the consequences of acute ischemic syndromes due to unstable plaques. We studied 30 carotid atherosclerotic plaques retrieved by endarterectomy from 18 asymptomatic (stable plaques) and 12 symptomatic patients (unstable plaques). Four normal arteries served as controls. After lipid extraction and ester hydrolysis, quantitation of different indices of oxidant stress were analyzed, including hydroxyeicosatetraenoic acids (HETEs), epoxyeicosatetraenoic acids (EETs), ketoeicosatetraenoic acids (oxo-ETEs), and F2-isoprostanes using online reverse-phase high-performance liquid chromatography tandem mass spectrometry (LC/MS/MS). All measurements were carried out in a strictly double-blind procedure. We found elevated levels of the different compounds in atherosclerotic plaques. Levels of HETEs were 24 times higher than EETs, oxo-ETEs, or F2-isoprostanes. Levels of HETEs, but not those of EETs, oxo-ETEs or F2-isoprostanes, were significantly elevated in plaques retrieved from symptomatic patients compared with those retrieved from asymptomatic patients (1, 738 +/- 274 vs. 1,002 +/- 107 pmol/ micromol lipid phosphorous, respectively; P < 0.01). One monooxygenated arachidonate species, 9-HETE, which cannot be derived from known enzymatic reactions, was the most abundant and significant compound observed in plaques, suggesting that nonenzymatic lipid peroxidation predominates in advanced atherosclerosis and may promote plaque instability. 相似文献