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用发生炉煤气进行快速热风烤窑的应用王善波,王志军(山东荣成市玻搪工程有限公司264309)ProducerGasUsedforFastHeatingupTankFurnace¥WangShanbo;WangZhijun(ShandongRongche... 相似文献
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本文从民用角度主要介绍了发生炉煤气站工艺流程,讨论了煤气站的经济性、存在问题及对策,从而确定发生炉煤气作为民用煤气的可行性。 相似文献
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缪良 《中国铸造装备与技术》2006,(3):10-13
中国已是铸件生产大国,但要成为铸造工业强国,还任重道远。从新中国成立以来,铸造工业取得的辉煌成就和现状谈起,分析了同工业先进国家相比,有那些主要差距,展望了中国铸造工业今后5~10年间的发展前景;提出了为促进铸造强国早日实现的六点建议。中国铸造工业的前景光明灿烂,为制造业提供一流铸件的时间已不遥远。 相似文献
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针对由两个制造商、两个回收商、当地政府和消费者构成的物流系统,研究了非合作条件下电子废弃物回收主体的利益博弈.在责任延伸制前提下,以回收商为斯坦伯格主导者,分别构建了非合作条件下的垄断回收模型和竞争回收模型,并采用逆推法求解了模型的纳什均衡条件.最后进行灵敏度分析,探讨了产品替代率和回收率对两种模式下产品销售价格和回收费用的影响.结果表明,对于回收商,垄断回收模式下的平均回收费用总比竞争回收模式高,且回收商需根据临界值选择回收模式;对于制造商,垄断回收模式下设定的价格总比竞争回收模式高,且制造商总是偏好竞争回收模式.研究结果可为决策者对回收模式的选择提供理论依据. 相似文献
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Arturo J. Fernández Carlos J. Pérez-González 《Computational statistics & data analysis》2012,56(3):719-731
Assuming that the probability of obtaining a defective unit in a production process, p, is not constant, a versatile methodology is presented for determining optimal failure-censored reliability sampling plans for log-location-scale lifetime models. The optimization procedure to decide the acceptability of a product is usually sufficiently accurate for the most widely used parametric lifetime models, such as the Weibull and lognormal distributions, and fairly robust to small deviations in the prior knowledge. Moreover, lower and upper bounds on the optimal sample size, and the corresponding acceptance constants, are derived in closed-forms. The proposed approach extends the traditional sampling plans to those cases in which appreciable prior information on p exists, and also allows the analyst the flexibility to delimitate the range of p and to incorporate into the reliability analysis prior impartiality between the producer and the consumer. In addition, the practitioners may achieve substantial savings in sample size, better information on the production process and better assessment of the true producer and consumer risks. An example related to the acceptability of a certain kind of gyroscope is included for illustrative purposes. Various practical prior distributions are considered to describe the random fluctuations in the proportion defective. 相似文献
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Xylanases (EC 3.2.1.8) hydrolyze the hemicellulose of plant cell walls. Xylanases are used in the food and paper industries and for bioconversion of lignocellulose to biofuel. In this work, the producer-strain with four copies of the xAor xylanase gene was organized in two tandem copies for optimal expression in Komagataella phaffii T07 yeast. The secreted 35 kDa xylanase was purified from culture medium by gel filtration on Sephadex G-25 and anion exchange chromatography on DEAE-Sepharose 6HF. Tryptic peptides of the recombinant enzyme were analyzed by liquid chromatography-tandem mass spectrometry where the amino acid sequence corresponded to Protein Accession # for Endo-1,4-beta-xylanase from Aspergillus oryzae RIB40. The recombinant xylanase was produced in a bioreactor where the secreted enzyme hydrolyzed oat xylane with an activity of 258240 IU/mL. High activity in the culture medium suggested xylanase could be used for industrial applications without being purified or concentrated. The pH optimum for xylanase xAor was 7.5, though the enzyme was active from pH 2.5 to pH 10. Xylanase was active at temperatures from 35 °C to 85 °C with a maximum at 60 °C. In conclusion, this protocol yields soluble, secreted xylanase suitable for industrial scale production. O94163相似文献
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The public has become increasingly interested in the welfare of food animals, but the food animal industries possess few mechanisms for public engagement. Here we present results from a web-based forum designed to allow stakeholders to share views on controversial issues in dairying. In response to the question “Should dairy calves be separated from the cow within the first few hours after birth?” participants were able to indicate “yes,” “no,” or “neutral” and either write a reason in support of their view or select reasons provided by other participants. Four independent groups of participants were recruited (a total of 163 people); 31% said they had no involvement in the dairy industry; the remaining 69% (with some involvement in the industry) were students or teachers (33%), animal advocates (13%), producers (11%), veterinarians (9%) and other dairy industry professionals (3%). Overall, little consensus existed among participants across groups; 44% chose “yes,” 48% “no,” and 9% “neutral.” Responses varied with demographics, with opposition to early separation higher among females, animal advocates, and those with no involvement with the dairy industry. A fifth group was recruited at a dairy industry conference (an additional 28 participants); 46% chose “yes,” 32% “no,” and 21% “neutral.” Across all 5 groups, opponents and supporters often referenced similar issues in the reasons they provided. Opponents of early separation contended that it is emotionally stressful for the calf and cow, it compromises calf and cow health, it is unnatural, and the industry can and should accommodate cow-calf pairs. In contrast, supporters of early separation reasoned that emotional distress is minimized by separating before bonds develop, that it promotes calf and cow health, and that the industry is limited in its ability to accommodate cow-calf pairs. These results illustrate the potential of web-based forums to identify areas of agreement and conflict among stakeholders, providing a basis for the development of practices that address shared concerns. 相似文献