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排序方式: 共有688条查询结果,搜索用时 15 毫秒
41.
何淑明 《重庆理工大学学报(自然科学版)》2007,21(16):16-19
跨国公司技术溢出效应本质上是经济外在性的一种表现,它是推动东道国经济发展的一支重要力量。对该领域的国内外研究状况进行了简要的回顾,并就该领域研究方面存在的不足和发展趋势提出了看法。 相似文献
42.
针对内生信息结构下供应链中阻止信息收集的问题,建立一个非线性规划模型.研究发现,存在一个作为给出不同契约参考点的信息收集成本阈值,进而给出了不同信息收集成本下阻止信息收集的契约,分析比较两种不同契约下供销双方的决策和收益,并且证明了当信息收集成本大于信息收集成本阈值时,供应商更愿意阻止信息收集.此时,供应商获得相对更好的收益,而销售商获得保留收益.最后给出的数值算例验证了主要结论. 相似文献
43.
This paper examines the reaction pathways and the nature of active sites for CO hydrogenation in general and C2+ oxygenate synthesis over Rh catalysts in particular. 相似文献
44.
Graves Franklynn C.; Wallen Kim; Maestripieri Dario 《Canadian Metallurgical Quarterly》2002,116(3):489
This study investigated the role of the endogenous opioid system in maternal and affiliative behavior of group-living rhesus macaque (Macaca mularta) mothers with a history of abusive parenting. 18 mothers received an injection of the opioid antagonist naltrexone or saline for 5 days per wk for the first 4 wks of the infant's life. After treatment, mother-infant pairs were focally observed. Naltrexone did not significantly affect infant abuse or other measures of maternal behavior. Naltrexone increased the amount of grooming received by mothers from other group members and reduced the mothers' rate of displacement activities such as scratching, yawning, and self-grooming. These results concur with previous primate studies in suggesting that opioids mediate the rewarding effects of receiving grooming and affect anxiety-related behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Bruehl Stephen; Burns John W.; Chung Ok Y.; Quartana Phillip 《Canadian Metallurgical Quarterly》2008,27(2):204
Objective: Previous work suggests that elevated trait anger-out exacerbates pain responses in part through endogenous opioid dysfunction. The authors examined whether this opioid dysfunction affects not only perceived pain intensity, but also emotional responses to being hurt. Design: 79 chronic low back pain (LBP) patients and 46 healthy controls received opioid blockade (8 mg naloxone i.v.) and placebo in randomized, counterbalanced order in separate sessions. During each session, participants sequentially experienced finger pressure pain and ischemic forearm pain tasks, with emotional state assessed at baseline and postpain. Main Outcome Measures: Blockade effects indexing opioid modulation of emotional reactivity were derived by subtracting placebo from blockade condition emotional reactivity. Results: Significant Participant Type × Anger-Out interactions on blockade effects indicated that in LBP participants but not in controls, greater anger-out was associated with deficient opioid modulation of anxiety, anger, and fear reactivity to noxious stimulation. Across participant types, greater anger-in was associated with impaired opioid modulation of anxiety and fear reactivity. Anger-in opioid effects were partially due to overlap with general negative affect. Conclusions: Opioid dysfunction associated with trait anger-out may affect not only perceived pain intensity, but also pain-related suffering in individuals with chronic pain conditions. Implications for understanding the health effects of anger management styles are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
D. Scaglione S. Caffaz E. Bettazzi C. Lubello 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(8):1250-1254
This paper describes an experimental method used to evaluate the anaerobic ammonium oxidation (Anammox) decay coefficient by means of a batch test. The test was carried out using an experimental procedure based on manometric measurements of the dinitrogen gas that is produced by the Anammox process. The accuracy of the procedure had previously been assessed, and the method was used to determine the specific Anammox activity (SAA mg N2‐N g VSS?1 d?1,) and the maximum nitrogen production rate (MNPR, NmL N2 L?1 d?1) under several different conditions. A specific batch test, which lasted for 148 days, was performed to assess the decay coefficient. The activity decrease was monitored and the estimated value of the decay coefficient was found to be 0.0048 d?1 at 35 °C, for which the corresponding half‐life time of the Anammox biomass was 145 days. This value is higher than other values reported in the literature, but in accordance with the slow growth rate of the Anammox bacteria. Copyright © 2009 Society of Chemical Industry 相似文献
47.
高校思政课是落实立德树人根本任务的关键课程。要提升高校思政课教学质量,真正实现“课堂革命”,必须探索适应新时代高校思政教育的课堂模式。首先厘清高校思政课内生需求,在此基础上把生态教学思维融入思政课堂,以问题设计为核心,以生态主体享有“获得感”为中心,构建“问题式”生态课堂模式。该模式更能充分实现教师和学生双向的“获得感”,从而更好地实现高校思政课教学模式的创新。 相似文献
48.
49.
食品加工工艺对大豆内源基因降解变化规律的影响 总被引:5,自引:0,他引:5
本文以转基因大豆和非转基因大豆为试验材料,运用定性PCR技术分析了磨浆、煮浆、调配、均质、点浆、杀菌、喷雾干燥等豆腐、豆奶、豆粉三种豆制品中关键加工工艺对大豆内源基因lectin的影响,探讨了转基因大豆加工食品在不同加工过程中DNA降解程度的变化。研究结果表明,大豆内源基因在三种加工食品中的各个加工过程中都会受到不同程度的破坏。在豆腐、豆奶、豆粉的加工过程中,片段大小为1883bp的lectin基因仅能在原料中检测到;磨浆、煮浆、均质等工艺,使lectin基因降解至1000bp以下;随着进行的点浆、高温杀菌或喷雾干燥等工艺对lectin基因的降解产生更显著的影响,豆腐终产品中lectin基因的片段大小在500bp以下,豆奶、豆粉中lectin基因片段大小仅为200bp左右。 相似文献
50.
即食发酵肉制品有着悠久的加工制作历史,因其营养丰富且具有独特的色泽和风味而深受消费者欢迎。迄今为止,未见即食发酵肉制品的熟化过程及其机制的全面综述。本文结合了近年来即食发酵肉制品相关研究进展,系统地阐述了其熟化过程中理化性质的变化,包括蛋白质和脂质的水解氧化、风味物质的形成以及质构的变化等。同时也总结了影响熟化的因素及其作用机制,包括酶的水解、发酵剂的抗氧化等以及腌制剂的呈味和增色的作用机制。最后讨论了现今研究存在的不足,并对未来的研究方向进行了展望,旨在为即食发酵肉制品的深入研究和发展提供理论依据。 相似文献