热处理对Ti-Mo-V-Nb-Al合金微观结构的影响

形状记忆合金由于其优良的超弹性和形状记忆效应而在医学上有着广泛的应用，其中由于NiTi形状记忆合金相较其它形状记忆合金具有更好的超弹性和生物相容性而得到了广泛的应用。但由于镍元素的毒性，使得开发一种生物相容性更好、无镍且具有良好力学性能的形状记忆合金成为必需。Ti-Mo-V-Nb-Al五元合金就是为此而开发的一种新型形状记忆合金。本研究用X射线衍射（XRD）、透射电子显微镜（TEM）和高分辨电子显微镜（HREM）研究了不同热处理条件对Ti-Mo-V-Nb-Al形状记忆合金微观结构的影响。     

按键电话机检修一例

一台香港生产的SHERITONE牌BSY9LDGR4044型收音电话机出现下述故障:当按下号码键后,脉冲信号发不出去,并且切不断通话蜂音,但外面来电话时铃能正常发声,通话也正常。由于该收音     

有线电视干线放大器的种类和选用

在目前的有线电视网中,特别是以电缆为主的网络中,有线电视干线放大器的正确选用不仅可保证传送信号的质量,而且可使干线的性价比最高. 　　……     

Measurement of the Seperation between Atoms beyond Diffraction Limit

We propose a scheme to obtain the distance of two identical atoms placed inside the standing wave field by monitoring the collective resonance fluorescence spectrum emitted by the two particles. We find three different parameter ranges, depending on the distance of the atoms as compared to the transition wavelength. For large interparticle distances, dipole-dipole coupling is negligible, and the main system evolution arises from the interaction with the standing wave field. In the small-distance limit, the dynamics is dominated by the dipole-dipole interaction. Finally, in the intermediate region, a rich interplay of the various couplings arises, which however is lifted for strong driving laser fields. The present measurement procedure allows us to distinguish the three cases. In each of the cases, we show how to determine the distance of the two particles and their respective positions relative to the nodes of the standing wave field with fractional-wavelength precision.     

用80C31和SED1335控制三星320×240LCD模块

本文介绍了一种经过实际应用的使用单片机80C31和SED1335液晶控制器控制LCD显示模块的软硬件设计,为设计各种便携式系统的显示前端提供了一种参考。     

ON THE UNIQUENESS OF THE WEAK SOLUTIONS OF A QUASILINEAR HYPERBOLIC SYSTEM WITH A SINGULAR SOURCE TERM

This paper is a continuation of the authors'previous paper[1].In this paper the authorsprove,assuming additional conditions on the initial data,some results about the existence anduniqueness of the entropy weak solutions of the Cauchy problem for the singular hyperbolicsystem a_t+(au)_x_2au/x=0,u_t+1/2(a~2+u~2)_x=0,x>0,t≥0.     

高衬底温度下溅射淀积二硅化钛膜

我们在室温和600℃下用复合的二硅化钛靶在〈111〉向的裸硅片上溅射淀积了二硅化铁膜。室温下淀积的二硅化钛膜需要在900℃下进行烧结,以使其电阻率降低。而600℃下淀积的二硅化钛膜已经反应充分形成颗粒较大的没有氧沾污的多晶状,而且该膜抗氧化。将该膜在900℃下进行进一步退火,发现其晶体结构、成分、电阻率即晶粒大小没有变化。     

混合Bitsadze-Lavrentév-Tricomi边值问题

It is well known that F. G. Tricomi (1923) is the originator of the theoryof boundary value problems for mixed type equations by establishing the Thicomi equation: y·u_xx+u_yy=0 which is hyperbolic for y < 0, elliptic for y=0. and parabolic for y= 0 and then applied it in the theory of transonic flows.Then A.V.Bitsadze together with M. A . Lavrent′ev (1950) established the Bitsadze Lavre nt′ev equation: sgn( y ) ·u_xx+u_yy=0 where sgn(y) = 1 for y > 0, = -1 for y<0, 0 for y=0 with the discontinuous coefficient sgn( y ) of u_xx, while in the case of Tricomi equation the corre sponding coefficient y is continuous. In this paper we establish the mixed Bitsadze Lavrent′ev Tricomi equation. Lu=K(y)·u_xx+sgn(x) ·u_yy+r(x,y)·u=f(x,y), where the coefficient K=K(y) of u_xx is increasing continuous and coefficient M=sgn(x) of u_yy discontinuous, r=r(x,y) is once continuously differentiable, f=f(x,y) continuous. Finally we prove the uniqueness of quasi regular solutions and observe that these new results can bbe applied in fluid dynamics.     

纪念声表面波器件的奠基人——英国物理学家瑞利发现瑞利波100周年声表面波器件的最新进展(二)

四、带通滤波器由本文第二部分可知,SAW带通滤波器设计的主要问题是推导合适的脉冲函数h(t),h(t)通过傅里叶变换与滤波器频率响应H(f)联系起来.通常,h(t)为无限值,所以必须对它截断,带通滤波器的实现.有限脉冲响应函数(其傅里叶变换给所需的“理想”频率响应以最佳近似值)的推导过程曾经是七十年代的主要研究课题.根据研究,几种非常有用的计算机辅助设计程序在目前已普遍采