A novel pulsation attenuator for aircraft piston pump

In this paper, a novel pulsation attenuator for pressure-controlled aircraft pump is developed, analyzed and tested. Several key components, such as pistons, the swash plate and the control valve, are modeled and discussed for analysis of the flow and pressure fluctuations. The structure, parameters and the location of the attenuator is investigated. The attenuator can adjust itself to keep its performance when the pump parameters changes within a certain range. The attenuator is also small enough to be integrated into the pump. Test results show that pressure fluctuation can be reduced with up to 80%.     

一种新型智能电子消毒鞋柜的设计与实现

介绍一种新型的消毒智能鞋柜,在采用单片机控制的同时,在杀菌理念上颠覆了传统的臭氧消毒的模式。利用光触媒与紫外线双重杀菌,杀菌消毒理念先进,较传统的臭氧消毒更具环保优势,同时PTC热风循环,使用更安全,再配合生物分解酶除臭,使消毒更彻底。这种技术能够胜任任何材料的消毒鞋柜,特别是板式材料为主的家具生产领域更具有优势。     

新钢1050m~3高炉节能操作实践

通过技术改造,新钢1 050 m3高炉先后实施了干法布袋除尘、TRT余压发电、富氧喷煤、余热回收等技术,并结合优化炉料结构,重视上下部调节,利用高风温、富氧喷煤和低硅冶炼等技术,取得了良好的节能效果。     

一种基于OPNET的多媒体业务半实物仿真平台

在深入研究网络仿真技术的最新发展“系统在环”技术的原理、分类和应用场景的基础上,结合当前应用最广泛的网络仿真软件OPNET及其SITL接口,创新地设计并实现了多媒体业务网络仿真平台,使得用户能够直观感受通过各种类虚拟仿真网络后的多媒体业务,为以音视频为主的多媒体业务网络的研究提供了高效的研究平台.     

基于应变耦合渗流模型的裂隙岩体弹性模量研究

原地直接测定裂隙岩体的弹性模量E_m,由于各种原因,在工程实践中往往有一定的困难。作为一种替代方法,通常人们利用实验室测得的岩石弹性模量E来确定裂隙岩体弹性模量E_m。提出的耦合应变渗流模型,建立了裂隙岩体中裂隙与岩块在应力作用下的变形协调和应力平衡关系,通过考虑裂隙岩体中地下开挖体涌水量大小可直接反映裂隙的贯通情况和密度大小这一事实,用地下开挖体涌水量大小和岩体弹性模量折减系数E_m来计算岩体弹性模量。为计算岩体弹性模量提出了一个可能的新途经。 该模型的结果与实际数据吻合良好。     

地表塌陷中隐伏土洞的形成与扩展机理研究

地表塌陷已成为危害城市安全和矿区生产的重要地质灾害之一,其产生一般经历了土洞的形成、土洞的扩展和顶板岩土层失稳3个过程。分析了土洞形成的机理及其力学机制,研究了土洞扩展的条件。分析了地下水在地表塌陷形成过程中的作用,从力学的角度揭示了地表塌陷的本质。研究结果表明,地下水的活动在土洞的形成到地表塌陷产生的全过程中起着关键性的作用。     

矿山生产数据管理系统的开发分析

运用ASP．NET、ADO．NET、SQL Server2000等最新的计算机编程技术，研究和开发基于Web的矿山生产数据管理系统，实现矿山生产管理的现代化，优化了工艺参数和技术指标，保证了企业生产稳定于最佳或接近最佳状态。系统根据“一次采集、全局共享、分级检索”的原则，通过采集矿山各二级单位的一次原始数据，经过集中分析处理，形成管理决策需要的各种报表及分析结果，以灵活的方式提供给各部门及领导检索，使公司和矿山各级领导能方便及时掌握企业生产状况，从而指导整个公司的生产。     

NuMA distribution and microtubule configuration in rabbit oocytes and cloned embryos

The assembly of microtubules and the distribution of NuMA were analyzed in rabbit oocytes and early cloned embryos. Alpha-tubulin was localized around the periphery of the germinal vesicle (GV). After germinal vesicle breakdown (GVBD), multi-arrayed microtubules were found tightly associated with the condensed chromosomes and assembled into spindles. After the enucleated oocyte was fused with a fibroblast, microtubules were observed around the introduced nucleus in most reconstructed embryos and formed a transient spindle 2-4 h post-fusion (hpf). A mass of microtubules surrounded the swollen pseudo-pronucleus 5 hpf and a normal spindle was formed 13 hpf in cloned embryos. NuMAwas detected in the nucleus in germinal vesicle-stage oocytes, and it was concentrated at the spindle poles in both meiotic and mitotic metaphase. In both donor cell nucleus and enucleated oocyte cytoplasm, NuMA was not detected, while NuMA reappeared in pseudo-pronucleus as reconstructed embryo development proceeded. However, no evident NuMA staining was observed in the poles of transient spindle and first mitotic spindle in nuclear transfer eggs. These results indicate that NuMA localization and its spindle pole tethering function are different during rabbit oocyte meiosis and cloned embryo mitosis.