离心式冷水机组在线监控系统研究

阐述了离心式冷水机且在线监控系统的工作特点以及对监控的要求，说明了在线监控系统的基本配置，关键技术点和功能模块化的软硬件设计。     

MX345芯片及单片机控制

MX345芯片用于产生模拟信令—CTCSS单音.本文在介绍MX345编码/解码器工作原理的基础上,设计出MX345芯片与单片机的接口电路.最后给出控制软件.     

Structure evolution of conductive polymer composites revealed by solvent vapor induced time-dependent percolation

The authors of this paper synthesized a series of amphiphilic triblock copolymers of polystyrene-b-poly(ethylene glycol)-b-polystyrene (PS-PEG-PS) having different PEG/PS ratios with nearly identical molecular weights of the entire copolymers. The interfacial interactions in the composites consisting of carbon black and the copolymers can thus be tailored. When these conducting composites are exposed to certain solvent vapors, their electrical resistances greatly increase, showing the gas sensitivity. The present work indicated that this switching behavior is controlled by the structural relaxation of the composites because matrix swelling acts as the main mechanism. The response time has been correlated with absolute temperature by Arrhenius equation, and the estimated activation energy reflects mobility of the fillers involved in the solvent induced expansion of the surrounding polymer. Therefore, by using the gas sensibility of the conductive composites, the structure evolution of the composite materials in solid state and the effect of filler/matrix interfacial interaction on the relaxation property of the matrix polymer has been inspected. It was found that lower activation energy represents stronger interfacial interaction in case good solvent of the matrix was used for the test.     

Control of Titanium Alloy Thin Plate Welding Distortion by Trailing Peening

The technology of trailing peening is a kind of promisingly bran-new technology which can be used to control weldingstress and distortion of Ti alloy thin plate. Control of TC4 Ti alloy thn plate welding stress and distortion underthe condition of convent     

唐钢一炼铁厂提高烧结矿质量的实践

介绍了唐钢第一炼铁厂近几年来围绕提高烧结矿质量 ,满足高炉冶炼需求所做的大量工作及成效 ,并提出了今后的打算     

Biomimetic synthesis of spherical nano-hydroxyapatite in the presence of polyethylene glycol

Spherical nano-hydroxyapatite (nano-HA) was synthesized successfully by a biomimetic method using Ca(NO₃)₂·4H₂O and (NH₄)₃PO₄·3H₂O as reagents in the presence of polyethylene glycol (PEG). The crystalline phase, microstructure, chemical composition, and morphology of the obtained samples were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). The results show that spherical nano-HA with diameter of 30–50 nm can be synthesized in the presence of a certain concentration (2–6%) of PEG. The crystallinity of HA powder synthesized in the presence of PEG was higher than that synthesized in the absence of PEG, but the crystallinity of HA reduced with increasing the concentration of PEG. The electrical conductivity (EC) of the solution revealed that PEG reduced the transfer rate of Ca²⁺ in the process of HA crystallization, indicating the interaction between PEG and HA. The possible mechanism of formation spherical nano-HA was discussed.     

基于BCM3540的高清晰度数字电视机顶盒的硬件设计

介绍一种基于BCM3540的高清晰度数字电视机顶盒的硬件设计方案,该方案采用1块主芯片BCM3540及1块协处理器BCM7411,能够处理MPEG-2高清、标清以及H.264高清、标清信号,可以直接支持PCMCIA接口实现机卡分离,并具有32位PCI总线,可以很方便地进行功能扩展。     

A new efficient numerical method and the dynamic analysis of composite laminates with piezoelectric layers

Firstly, a numerical method for the inversion of Laplace transform is developed and its accuracy is shown through examples. Then, a state-vector equation for the dynamic problems of piezoelectric plates is deduced directly from a modified mixed variational principle for piezoelectric bodies and its exact solution for the dynamic problems of simply supported rectangle piezoelectric plate is simply given. For multilayered hybrid plates, we derive the solution in terms of the propagator matrices. The techniques accounts for the compatibility of generalized displacements and generalized stresses on the interface both the elastic layers and piezoelectric layers, and the transverse shear deformation and the rotary inertia of laminate are also considered in the global algebraic equation of structure. Meanwhile, there is no restriction on the thickness and the number of layers. As an application of the numerical inversion of Laplace transform presented in this paper, typical numerical examples of the harmonic vibration and transient response are proposed and discussed. Since the highly accurate numerical results, they can serve as benchmarks to test various thick plate theories and various numerical methods, such as the finite and boundary element methods for transient response problems.     

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研究燃料汽车及其氢源系统是当今国内外能源工业与汽车工业的共同课题，而优选制氢能源则是这一课题的关键。章介绍了利用能源、经济、环境(EEE)——生命周期评估(LCA)这一综合评估方法，针对以天然气、煤或石油作为制氢能源的多种燃料电池氢源供应方式以及配套的燃料电池汽车系统，从经济性、能源利用效率和环境影响三个方面进行了生命周期清单分析和EEE综合评价。结果显示：天然气作为发展燃料电池汽车氢源的一次能源，具有氢制取技术路线多样化、经济上竞争力强、能源利用效率高和环境效益好等诸多优势，应为燃料电池汽车的首选制氢能源。对这一评估模型的敏感性分析显示，即使在天然气价格波动较大时，天然气制甲醇--甲醇车载重整车和天然气制氢--纯氢车这两个方案仍然最具优势。     

钢包炉(LF)预熔精炼渣的研究

预熔精炼渣具有成分均匀，性能稳定，储存时不吸水等特点，钢包炉中使用预熔精炼渣时成渣均匀且速度快，具有较强的吸附钢中非金属夹杂的能力。综合脱硫率高等冶金效果。有显著净化钢液作用。