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排序方式: 共有797条查询结果,搜索用时 15 毫秒
51.
韩利凯 《数字社区&智能家居》2006,(4):209-209,217
从课程建设的目标、教学内容、教师队伍和教材建设、教学方法、实践环节等方面阐述了对计算机专业核心课程《数据结构》精品课建设的研究,提出了以教师为主导,以学生为主体,优化教学,深入改革的内容和方法。 相似文献
52.
Intelligent agents in electronic markets for information goods: customization, preference revelation and pricing 总被引:4,自引:0,他引:4
Electronic commerce has enabled the use of intelligent agent technologies that can evaluate buyers, customize products, and price in real-time. Our model of an electronic market with customizable products analyzes the pricing, profitability and welfare implications of agent-based technologies that price dynamically based on product preference information revealed by consumers. We find that in making the trade-off between better prices and better customization, consumers invariably choose less-than-ideal products. Furthermore, this trade-off has a higher impact on buyers on the higher end of the market and causes a transfer of consumer surplus towards buyers with a lower willingness to pay. As buyers adjust their product choices in response to better demand agent technologies, seller revenues decrease since the gains from better buyer information are dominated by the lowering of the total value created from the transactions. We study the strategic and welfare implications of these findings, and discuss managerial and technology development guidelines. 相似文献
53.
对从广州口岸进口的植物及其产品、动物性药材和进口国际邮包随带的仓储害虫,进行系统调查。收集害虫标本,并进行分类整理和鉴定。从来自23个国家和地区的产品中,收集的仓储害虫有2个目、21个科、63种。其中有些为对外植物检疫对象,有些则为内检对象,有些虽然属一般仓储害虫,但含虫量高、密度大。在检疫中发现的疫情,采用熏蒸杀虫等方法处理。 相似文献
54.
危险货物包装种类、材质、规格不一,其性能测试要求也不一样。在不影响检测结果准确性的前提下,可用模拟物替代实际内装物质或物品进行测试。危险货物包装的性能检测主要包括跌落试验、气密试验、液压试验、堆码试验,分别对应于危险货物包装所应具备的抗冲击、密封性、耐内压和强度等性能要求。在检测时,应注意其试验要求、试验条件、合格判定准则及检测关键控制点。检测实践发现,危险货物包装检测不合格主要有:瓦楞纸箱堆码检测不合格,塑料桶液压测试不合格,钢塑复合桶液压测试不合格,钢桶跌落测试及液压测试不合格,纸板桶跌落测试不合格等。未来包装检测应朝着标准化、规范化和科学化方向发展,尽量减少人为因素的影响。 相似文献
55.
In this paper, we study the problem of auctioning a kind of continuous homogeneous divisible goods, and present a multi-stage sequential auction mechanism of divisible goods under uniform price. In this mechanism, the auction process is divided into multiple stages, all bidders satisfy the sequential rationality conditions, all bidders are asymmetric, every bidder is allowed to submit a nonincreasing continuous demand function in each round bidding, every bidder’s valuation to per unit of the goods is independent private information, and if a bidder does not obtain the quantity he wants in former stage auction, he still have another opportunity to obtain some quantity in the later stage auction. For this mechanism, we explore the formation process and composition of equilibrium points in each stage auction, and discuss the optimal strategy selection for bidders, then give the detail steps and an application example to show how to implement this multi-stage sequential auction mechanism. The conclusions can be drawn that our auction mechanism is an efficient incentive mechanism, and can effectively reduce many underpricing equilibrium and can yield higher expected income than a single uniform price auction for the auctioneer. It also can avoid the occurrence of failure auction (equilibrium does not exist), and effectively extend and improve the traditional single stage uniform price auction mechanism. 相似文献
56.
纯棉针织物的活性染料"一次准"染色工艺探讨 总被引:2,自引:0,他引:2
为实现活性染料对纯棉针织物“一次准”染色,在前处理、染色工艺方面进行改进。前处理采用非烧碱氧漂特效助剂+双氧水;染色前采用脱氧酶去除织物上残留的双氧水,减少漂后水洗次数,缩短工艺流程;改进传统染色升温、加料方法。详细论述了生产中各个工序的技术管理要求,加强对染化料助剂库、化验室和染色等工序的严格管理,是实施染色“一次准”的基础。 相似文献
57.
《中国标准化(英文版)》2008,25(1)
Editor's Note: After two decades of development Haier has become the fourth largest white goods manufacturer in the world, and one of the most valuable brands in China. In 2007, Haier's global turnover was more than 100 billion RMB. 相似文献
58.
Berninghaus Siegfried K.; Güth Werner; Kirstein Annette 《Canadian Metallurgical Quarterly》2008,1(1):33
Systematic experiments with distribution games have shown that participants are strongly motivated by considerations of fairness and efficiency. This evidence, however, results mainly from experimental designs in which money is shared directly. Furthermore, fairness does not necessarily require equal payoffs, but may instead require equal allocations. We investigate experimentally the frame dependency of reaching equal (commodity or payoff) splits by systematically comparing net-trade proposals and payoff proposals for the same exchange economy with two traders, two commodities and multi-period negotiations. We can confirm the hypothesis that asking participants to allocate money directly, rather than more naturally via the allocation of commodities, is far from being harmless and likely overstates fairness and efficiency concerns. What is more, we try to apply the insights gained from our experiment to management problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Jan Fritsche Katharina D. Petersen Gerhard Jahreis 《European Journal of Lipid Science and Technology》2010,112(12):1363-1368
In the present study, 122 food samples from the German food market were analysed for their C18:1 trans fatty acid (TFA) content and profile. A particular focus of the survey were baked and fried foods. TFA analysis was performed by means of silver ion SPE (Ag+‐SPE) in combination with high‐resolution GC (HRGC‐FID). Overall, 51 bakery product samples were analysed of which 25 samples were prepacked bakery products purchased from local retail stores and 26 samples of unpacked bakery products purchased from local bakery shops. In addition, 14 French fries samples obtained from small local fast food restaurants as well as from internationally operating fast food chains, 27 potato and tortillas chips, 15 instant soups as well as 15 dry culinary sauces were analysed. The highest amounts of C18:1 TFA isomers were found in deep‐fried bakery products. Prepacked branded cookies and biscuits on the other hand contained only negligible C18:1 TFA amounts. Regarding their C18:1 trans isomer profile most deep‐fried bakery products exhibited a Gaussian‐distributed isomer profile. The analysed prepacked croissants, cookies and biscuits contained predominantly ruminant TFA (TFA) as suggested by the presence of vaccenic acid (C18:1 trans 11), which was the major C18:1 TFA isomer in these products. All non‐bakery samples (n = 71) contained less than 3 g C18:1 TFA per 100 g fat. In conclusion, TFA still occur in considerable amounts in a few German food products, especially in some deep‐fried bakery products (‘Berliner’ type of doughnuts). Practical applications: Trans fatty acids, in particular the trans octadecenoic fatty acid isomers (C18:1), are generally considered from the nutritional point of view as undesirable food components due to their negative health effects. Tremendous efforts have been made by major food processors in order to decrease or even eliminate the presence of TFA in some foodstuffs (e.g. in margarines in European countries). However, some food processors of other food sectors are still applying oils and fats containing partially hydrogenated vegetable oils, whereas others within the same food category have already switched their processing conditions and/or raw materials towards TFA alternatives. Therefore, actual TFA data of foodstuffs determined by means of state‐of‐the‐art analytical procedures (Ag+‐SPE in combination with GC‐FID) is necessary to detect areas of further improvement in the food supply chain and to provide data for an update of dietary TFA intake. 相似文献
60.