Insensitive current/voltage-mode filters using FTFNs

A new configuration for realising insensitive current/voltage-mode filters using two four-terminal floating nullors (FTFNs) is presented. It can provide the curren/voltage-mode filters with reduced sensitivities. Moreover, the current-mode filters can have high output impedance and only grounded capacitors. The proposed universal voltage-mode filter with dual outputs can realise lowpass, bandpass, highpass, notch and allpass filtering functions. Simulation results are given to verify the theoretical analysis     

开发计算机管理信息系统推动设备供应管理现代化

本文介绍了我国冶金大型钢铁联合企业设备供应管理系统计算机应用开发过程及研制方法，并分析了取得的经济效益和在国内的推广价值。     

轧制规程优化设计

介绍了板、带材压下规程及型材的孔型优化设计问题，并指出了设计特点与方法，给出了优化后的效果。为钢材及其它有色金属轧制规程的设计提供了设计方法。     

Photoacoustic ultrasound: pulse production and detection of 0.5% Liposyn

Theoretical predictions and experimental measurements of photoacoustic pulse production within a 0.5% solution of Liposyn, a highly scattering, optical propagation medium, are reported. A simple model for photoacoustic energetics is developed that predicts photoacoustic signal pressure as a function of depth within a turbid medium following surface irradiation from an infrared source. The model is valid for very short irradiation duration. The model predicts that the acoustic pressure produced at a distance r from the center of a small, highly absorbing sphere of radius R consists of two, opposite polarity pulses, one originating from the near and one from the far side of the sphere. The magnitude of these biphasic pulses is expected to be proportional to the energy fluence (E) incident on the surface of the sphere and to the ratio, R/r. Furthermore, the energy fluence (E) that reaches the sphere is roughly proportional to e-mu effZ, where mu eff is the effective attenuation coefficient of the turbid medium and Z is the depth of the embedded sphere below the irradiated surface. The variation of E with depth within the absorber and biphasic acoustic pulse production have been verified experimentally. Further experiments demonstrate that a small (3-mm diameter), highly absorbing sphere can be detected and localized at a depth of 37.5 mm within a 0.5% solution of Liposyn with a spatial resolution of 1 x 6 mm2, using a biologically safe level of infrared irradiation (lambda = 1064 nm) and a conventional ultrasound transducer (frequency = 2.25 MHz). These results suggest that photoacoustic ultrasound imaging may have application to biologic systems such as the human breast.     

工字钢腿腰延伸系数均匀分配的计算方法

对轧制工字钢采用一种新的腿腰划分方法，用计算机迭代计算，使腿腰延伸系数趋于均匀更趋于实际，使孔型设计更为合理。     

meso-四-(4-甲氧基-3-磺酸苯基)卟啉在测定痕量金属的应用—锌的分光光度法测定

本文研究了在咪唑存在下 meso—四—(4—甲氧基—3—磺酸苯基)卟啉(TMPPS_4)与锌显色反应的最佳条件,建立了测定锌的新方法,灵敏度高,锌量在0—1.2μg/10mL 范围内遵守比耳定律,用于测定粮食中的锌时结果满意     

水煤浆分散剂制浆性能和物化性质的研究

选取3种具有代表性分散剂研究其制浆性能和物化性质的相关性得出:分散剂吸附层厚度和制浆性能有较好的相关性,并借助HVO理论讨论分散剂与煤作用机理,揭示出一种理想分散剂在结构上应有的特征。     

QFD质量职能扩展简介

介绍ＱＦＤ（质量职能扩展）的发展历史及其具体的操作过程。     

砼回弹法测强统计分析

简述了砼回弹法测强与抗压强度对比试验的方法，得出了影响砼回弹测强的种种因素，通过统计分析给出了砼回弹测强的实用计算公式，从而就可在结构物上直接进行回弹测强，达到及时，方便，准确地了解结构物的强度．     

焊前处理方式对LF6铝合金扩散焊的影响

利用Ｇｌｅｅｂｌｅ－１５００热／力模拟试验机，研究了ＬＦ６铝合金的扩散焊工艺，通过对焊接温度、压力、时间的调整和选用不同的料前处理方法，确定了最佳的扩散规范，研究结果表明：在一定的温度和时间范围内，ＬＦ６５铝合金扩散焊接头的剪切哟度随焊接温度和时间的增加而提高；化学浸蚀法比机械打磨法能更有效的去除铝合金表面的氧化膜；在现有试验条件下，得到ＬＦ６铝合金扩散焊的最佳规范参数，搭接试扩散焊接头的剪切强度