Elastic constants of face-centered cubic and L1<Subscript>2</Subscript> Ni-Si alloys: Composition and temperature dependence

The adiabatic elastic stiffness constants C _ij of Ni-Si single-crystal solid-solution alloys of two slightly different compositions, 10.78 and 11.17 at. pct Si, were measured over the temperature range from 20 °C to 900 °C using the rectangular parallelepiped resonance method. The isotropic elastic constants of the polycrystalline ordered intermetallic compound Ni₃Si containing 23 at. pct Si were also measured over this temperature range. Values of the C _ij for Ni₃Si were estimated from the data on the polycrystalline alloy, as well as from published data in the literature on isomorphous ternary ordered intermetallic compounds containing different amounts of Si. Using measured values and previously published data, the stiffness constants of Ni₃Ti were estimated; these are the only available data on this alloy. The estimated single-crystal elastic constants of Ni₃Si, as well as the experimentally measured bulk modulus, are considerably smaller than published values calculated from first-principles methods. The same is true for the C _ij of Ni₃Ti, but the discrepancies are smaller.     

煤基链篦机-回转窑一步法直接还原设备改造及技术操作要点

本文主要论述了煤基链篦机-回转窑一步法直接还原关键设备改造及有关技术操作要点，并提出了进一步提高产量，稳定操作，延长作业周期，降低生产成本的技术改造方案。     

TPS/TDC3000系统串口通讯的规划与应用

针对TPS/TDC30 0 0系统串口通讯方式、机理进行了一般性的介绍 ,对规划与应用中常见的的问题 ,根据实际工程应用经验提出了解决方案。     

Transcutaneous balloon angioplasty in the treatment of subclavian steal syndrome. Characteristics of vertebral basal flow with transcranial Doppler technique

Subclavian steal syndrome (SSS) appears when the origin of the subclavian artery (SA) is occluded or stenosed. Introduction of transcranial Doppler sonography (TCD) provided an opportunity to evaluate parameters of the blood flow in the vertebral (VA) and basilar artery (BA). Measurements of blood flow velocities performed at rest and after the brachial hyperemia test allow one to classify hemodynamic types of SSS. The aim of the study was to categorize types of steal and to compare the differences of flow patterns before and after percutaneous transluminal SA balloon angioplasty (SA-PTA). Fourty-eight patients with angiographically confirmed SSS (aged from 27 to 68 years, mean 53; 2/1 f/m ratio) were examined with 2 MHz range-gated, pulsed transcranial Doppler device (TC 2-64B EME). Both VA and BA were evaluated by the transoccipital approach at rest and during the brachial hyperemia. In 5 cases (10.4%) permanent reversal blood flow in the BA was observed (complete basilar steal). In flow in the BA blood flow was in the normal direction at rest and altered (reversed or decreased) when induced with brachial hyperemia test (transient basilar steal). In the next 14 patients (29.2%) permanently reversed VA blood flow was observed with only a slight or no alterations of the BA flow after the hyperemia test (complete vertebral steal). In the last 19 cases (39.6%) alterations of the VA blood flow without changes in BA flow were observed (latent vertebral steal). Between 1991 and 1994 twenty seven symptomatic patients with different hemodynamic types of SSS were treated with SA-PTA. TCD evaluation of VA's and BA using the hyperemia test was performed before, 3 to 7 days and 3 months after morphologically and hemodynamically successful subclavian artery balloon PTA. Normal results of vertebrobasilar examinations were obtained in 26 cases after this procedure. In one case the latent vertebral steal was detected. The 28 months mean follow-up revealed no significant changes in TCD flow patterns recorded from VA's and BA. After collecting data of about 60 patients with SSS we examined with TCD we conclude that: in patients with a hemodynamically significant SA stenosis the presence of reversed ipsilateral VA blood flow (a radiologic steal) its not a good determinant of either the presence or type of presenting symptoms and after successful PTA or recanalisation and PTA of SA in almost all cases we examined close to normal TCD recordings in BA and VA.     

多冗余点到点链路下OSPF扩散算法的一种改进方案

文章讨论了OSPF路由协议的扩散算法在多冗余点到点链路情况下存在的缺陷,提出了一种基于扩散接口选举的改进方案。     

部分种子成分的特征X射线在等效生物材料中衰减的测定

用Ｓｉ（Ｌｉ）探测器实现了Ｎａ、Ｍｇ、Ｓ、Ｃｌ的特征Ｘ射线在有机膜中的相对衰减以及与Ｏ、Ｋ元素的特征Ｘ射线能量相当的Ｘ射线或轫致辐射在有机膜中的相对衰减，分别得出了它们减的数学描述，并把实验得到不同能量的Ｘ射线在有机膜中的质量吸收系数与Ｂｅｒｋｅｌｅｙ的ＯＣＧ软件计算出的结果相比，相关都小于３０％。     

金属－橡胶硫化粘接过程中分子取向行为的间接证据

对金属－橡胶热硫化粘接复合体的剥离行为进行了研究，同一粘接试样的双向１８０°剥离试验显示出了巨大的差异。本文分析了弹性材料在硫化过程中的分子行为，并提出了相应的新假设，认为这是由于金属－橡胶在硫化粘接过程中分子取向交联行为所致。这种双向１８０°剥离破坏现象可被看作是金属－橡胶硫化粘接过程中分子取向行为的间接证据。     

VAX机分布式电网调度自动化系统的实现

本文介绍作者开发的一个电网调度自动化系统ＥＰＧＣ。首先介绍ＥＰＧＣ的系统结构，然后介绍系统的软件结构，并着重介绍主机软件数据库，以机监视与切换，网络通信子系统的实现方法。最后对系统的安全可靠性进行简要分析。     

Nedocromil sodium in treatment of bronchial asthma

Clinical study on efficiency of the nedocromil sodium (Tilade, Fisons) was performed in 20 patients with atopic and nonatopic bronchial asthma. The drug was administrated in dose of 8 mg per day for 2 months which allowed to renounce regular using of Beclocort forte after 7 days of the treatment. In both types of bronchial asthma the positive effect of nedocromil sodium was confirmed, causing increase of pulmonary ventilation and decrease of bronchial hyperactivity. Especially profitably effect was noticed in atopic bronchial asthma in which statistically important increase of peak expiratory flow (PEF) was obtained and decrease of bronchial hyperreactivity by PC20 for histamine was observed (p < 0.05). Mentioned above spirometric parameters did not differ in statistically important pattern in patients with nonatopic bronchial asthma, when Beclocort forte group with Tilade group compared. Neither important differences in general number of cells nor percentage composition of cell smears were observed in bronchoalveolar lavage fluid.     

叠轧薄板轧机轧辊轴承的改进

本文针对安阳钢铁公司薄板厂叠轧薄板轧机轧辊轴承轴瓦容易损坏、沥清润滑油冒烟起火这一问题，通过实验方法，找出了原因，并对大铜瓦进行了改进，取得了良好效果。