基于自相似通信量输入的带宽分配算法

自相似网络通信量的发现及其对排队系统性能的影响已经得到了大量的研究。该文研究了自相似通信量输入条件下FIFO排队系统的带宽分配问题。首先得到了假设条件下排队系统的所要求带宽的上界。然后在此基础上研究了同种和异种自相似输入通信量输入情况下的带宽分配策略。最后通过仿真分析验证了所得到结果的有效性。     

BFe30-1-1白铜管早期腐蚀失效原因分析

某电厂凝汽器BFe30-1-1白铜管投运后几年内出现较为严重的局部腐蚀和点腐蚀，为此，对材质、水质等诸多因素进行了分析研究，通过宏观、微观检查和电化学试验，认为是微生物及生物粘泥的附着引起了铜管的早期腐蚀失效。     

The Power of the Brown v. Board of Education Decision: Theorizing Threats to Sustainability.

Interviews with African American and White American elders capture the immediate power of the Brown v. Board of Education (1954) decision and the biography of its impact over time. This article reviews the lived experience of the decision and theorizes 3 threats to sustainability that ruthlessly undermined the decision over time: (a) the unacknowledged and enormous sacrifice endured by the African American community in the name of desegregation; b) the violent and relentless resistance to the decision by government officials, educators, and many White community members; and (c) the dramatic shrinkage of the vision of Brown from the dismantling of White supremacy to a technical matter of busing. Implications are drawn for the study of desegregation and for the study of sustainability of social justice more broadly. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Scientific Attack on Brown v. Board of Education, 1954-1964.

Psychologists' work was cited in the Supreme Court case of Brown v. Board of Education (1954). One criticism of the citation was that psychology could be used to overturn the Brown decision and return the country to segregation. A historical examination of such an attempt to overturn Brown in the early 1960s on the basis of new psychological knowledge shows that psychology was not persuasive in the face of the civil rights movement. The failure of segregationists to overturn Brown with psychological experts underscores how psychology is ineluctably bound to the larger society. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

一种新型节能电动油脂润滑泵的设计

设计了一种新型电动油脂润滑泵的结构组成及工作原理,该泵采用微控制器自动控制润滑油脂定时定量输送至各润滑点,并配以液位开关实现低油位报警,大大减少了电机损耗,节省所需的油脂及电力,具有良好的应用前景.     

含钼化合物在润滑脂中的抗磨性能研究

采用四球机考察了二烷基二硫代磷酸钼(MoDDP)、二烷基二硫代氨基甲酸钼(MoDTC)、非硫磷有机钼等3种有机钼化合物以及三氧化钼、钼酸铵2种无机钼化合物在润滑脂中的抗磨性能.结果表明:3种有机钼化合物在润滑脂中都有良好的抗磨性能,特别是高浓度的MoDDP在高负荷下仍具有优良的抗磨性能,非硫磷有机钼在低负荷下的抗磨性能比较突出;2种含钼固体无机化合物在润滑脂中也具有良好的抗磨性能,特别是钼酸铵,这为直接应用于润滑脂中提供了可能.     

WS_2锂基润滑脂的制备及其摩擦学性能研究

采用95 nm、0.74和1.75μm 3种不同粒径WS2粉体作为添加剂制备了锂基润滑脂,并利用四球摩擦磨损试验机分别考察了其摩擦学性能,采用SEM、EDAX、XPS分析了磨损表面的形貌、元素成分及其化学状态。结果表明,WS2作为润滑脂添加剂具有非常优异的摩擦学性能,其中95 nm粒径WS2粉体表现出的性能最优。研究表明WS2添加剂的润滑作用机理是吸附膜,沉积膜或化学反应膜相互作用的结果,不同润滑状态其作用方式也不同,在中高载荷条件下吸附在摩擦副表层的WS2易发生渗镀现象,并可在亚表层内形成致密的WO3化学反应膜。     

高压油脂注油机的研制

分析了手动液压油脂注油机、电动黄油注油机的优、缺点 ,介绍了最新研制的高压油脂注油机的结构特点、工作原理以及参数选择。现场应用表明 ,该装置装油方便、注油压力高、出油率高、性能可靠 ,解决了目前注油机注油量小和不能连续注油的难题。     

The antiwear and extreme pressure action mechanism of CeF3 in grease

Cerium (III) fluoride as an antiwear or extreme pressure additive has been used in grease and bonded solid film lubricant, but its action mechanism has not been clarified. In this paper, the tribological characteristics of lithium grease containing CeF₃, CaF₂, SbF₃, CeO₂ and graphite fluoride ((CF)_n) were evaluated with an SRV tester. The results show that pastes containing CaF₂ and (CF)_n give good antiwear and anti-friction performance, but do not possess extreme pressure properties. Adding CeO₂ to grease offers no benefit to the antiwear and anti-friction performance of the paste. Paste containing SbF₃ has poor lubricating properties. XPS analysis shows that the good antiwear and extreme pressure properties of paste containing CeF₃ can be attributable to the formation of a physically adherent film and a chemical reaction film on the rubbing surface. Thermogravimetry shows that CeF₃ acts as an agent for the slow release of the fluorine element.     

钢厂润滑脂的最近动态

从满足设备的可靠性,提高生产效率,降低生产成本和减少对环境的冲击方面,介绍了使用高性能、长寿命的脲基润滑脂和复合磺酸钙基润滑脂在钢厂的应用情况.