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101.
用于处理高浓度钨酸钠溶液的离子交换新工艺 总被引:3,自引:0,他引:3
开发了离子交换新工艺用于处理高浓度钨酸钠溶液。与传统工艺相比,新工艺既保持了传统工艺的优点,又突破了对交前液浓度的限制,可在高的WO3浓度、高的NaOH浓度的条件下实现钨的吸附、净化和转型。吸附时对溶液流速的限制也大幅度放宽。由于采用高浓度溶液进行离子交换,稀释用水可以大幅度削减。相应车间建筑空间和动力消耗也得以下降,设备的处理能力则相对上升。另外交后液体积锐减,易于处理甚至处理后回用以降低化工原料NaOH的消耗和环境污染。 相似文献
102.
T. AGODA E. MACHA A. NIESONY 《Fatigue & Fracture of Engineering Materials & Structures》2005,28(4):409-420
The paper contains a new algorithm for estimation of fatigue life in HCF regime under multiaxial random loading using spectral methods. Loading of Gaussian distribution and narrow‐ and broad‐band frequency spectra were assumed. Various characteristic states of multiaxial loading were considered. The equivalent stress history was determined with use of the failure criteria of multiaxial fatigue based on the critical plane. For determination of the critical plane position, the method of variance was applied. During simulation, the authors compared the results obtained by a spectral method in the frequency domain with those from the rain‐flow algorithm in the time domain. The paper also contains the results of fatigue tests for 18G2A structural steel subjected to bending and combined bending with torsion. The tests were performed in order to verify the proposed algorithms for determination of fatigue life. It has been shown that under multiaxial random loading results of fatigue life calculated according to the considered algorithms in frequency and time domains are well correlated with the results of experiments. 相似文献
103.
本文介绍了一种以新型智能功率模块IPM,SPWM专用控制芯片80C196MC为基础构成的交流牵引变频调速控制系统,介绍了系统的控制原理及软硬件的设计方案。 相似文献
104.
张彩霞 《南通纺织职业技术学院学报》2003,3(4):72-74
通过对高职学生中存在的网络成瘾问题的长期关注,对其危害深有感触,着重分析其内外诱因,讨论了用团体辅导的方式等进行调适的办法。 相似文献
105.
机械设计制造及其自动化专业高素质人才培养探讨 总被引:1,自引:1,他引:1
简要介绍机械设计制造及其自动化专业人才的培养目标和业务规格,特别对如何培养专业水平高、实践能力强、综合素质全面的高层次专业人才进行详细探讨。 相似文献
106.
Pingguang Xu Bingzhe Bai Hongsheng Fang Zhenjia Wang Jianping Wang Yongkun Pan 《北京科技大学学报(英文版)》2003,10(2)
A new hot-rolled low alloy high strength steel with grain boundary allotriomorphic ferrite/granular bainite duplex micro-structure has been developed through novel microstructure and alloying designs without any noble metal elements such as nickel and molybdenum. Its as-rolled microstructure and mechanical properties, fatigue crack propagation behavior compared with single granular bainitic steel as well as continuous cooling transformation, were investigated in detail. The measured result of CCT (continuous cooling transformation) curve shows that such duplex microstructure can be easily obtained within a wide air-cooling rate range. More importantly, this duplex microstructure has much better combination of toughness and strength than the single granular bainite microstructure. It is found that the grain boundary allotriomorphic ferrite in this duplex microstructure can blunt the rni-crocrack tip, cause fatigue crack propagation route branching and curving, and thus it increases the resistance to fati 相似文献
107.
刘军 《武汉理工大学学报(材料科学英文版)》2003,18(1):61-64
1 IntroductionThehighmechanicalproperties ,gooddurabilityandappropriateworkabilityarenecessaryforhighperformanceconcretetosatisfytheconstructionrequirementoflarge scaleconcreteengineering .Accordingtodifferentapplica tionsandpurposes ,inordertoimprovethe… 相似文献
108.
SABUL: A Transport Protocol for Grid Computing 总被引:5,自引:0,他引:5
This paper describes SABUL, an application-level data transfer protocol for data-intensive applications over high bandwidth-delay product networks. SABUL is designed for reliability, high performance, fairness and stability. It uses UDP to transfer data and TCP to return control messages. A rate-based congestion control that tunes the inter-packet transmission time helps achieve both efficiency and fairness. In order to remove the fairness bias between flows with different network delays, SABUL adjusts its sending rate at uniform intervals, instead of at intervals determined by round trip time. This protocol has demonstrated its efficiency and fairness in both experimental and practical applications. SABUL has been implemented as an open source C++ library, which has been successfully used in several Grid computing applications. 相似文献
109.
Electromagnetic wave propagation close to a material discontinuity is simulated by using summation by part operators of second, fourth and sixth order accuracy. The interface conditions at the discontinuity are imposed by the simultaneous approximation term procedure. Stability is shown and the order of accuracy is verified numerically. 相似文献
110.
多通道同步高速数据采集系统研制 总被引:3,自引:2,他引:3
介绍了一个最高采样率为100MHz,采样精度为8bit,基于PCI总线和计算机并口的8通道同步高速数据采集系统的设计,整套系统具有同步误差小、触发方式多样、操作灵活等特点。 相似文献