Applications of Thermoelectric Power Measurement to Deterioration Diagnosis of Nuclear Material and Its Principle

In order to non-destructively evaluate changes in toughness of cast duplex stainless steel, which is frequently used in main coolant pipes of PWR type nuclear power plants, due to thermal aging, we tried to apply thermoelectric power (TEP) measurement. because TEP is sensitive to microstructural material changes, and to clarify the mechanism behind TEP changes due to thermal aging. As a result, TEP of cast duplex stainless steel increased with aging time, and good correlations were found between TEP and toughness. Concerning the mechanism, TEP of high and low Cr content alloys was higher than that of intermediate Cr content alloys. Because high and low Cr areas are created in the ferrite phase due to thermal aging. TEP of the entire material increased. Furthermore, when each Cr fluctuating area acted in parallel, the increase in TEP became larger. According to the Mott-Jones theory, TEP is largely related to the electron density of states at the Fermi level. The electron density of states of Fe–Cr–Ni alloys in the valence band was measured with X-ray photoelectron spectroscopy (XPS). As a result, there was a high correlation between the TEP calculated from the XPS spectrum and the measured TEP. Therefore, we showed experimentally that the electron density of states changed due to variations in Cr concentration, which also affect TEP.     

Two Pseudogap Behavior in La2?xSrxCuO4: Thermoelectric Power at High Temperature

Thermoelectric power (TEP) of high-T _C superconductors has been investigated in a wide range of temperature (T _C < T < 700 K) for La_2–x Sr _x CuO₄. TEP of La_2–x Sr _x CuO₄ shows different temperature dependences in three temperature regions. In the low-temperature region, a positive broad TEP peak is observed near T _p, which shifts to lower temperature upon doping. As temperature increases, TEP decreases linearly at intermediate temperature. In the high-temperature region, TEP deviates from the linear temperature dependence at a certain temperature, T _h showing a saturation behavior. As the doping concentration increases, the characteristic temperatures, T _C, T _p, and T _h, show systematic changes. In comparison with pseudogap temperature estimated from other experiments, the large pseudogap behavior in TEP at high temperature has been discussed and distinguished from the small pseudogap observed at lower temperature. A possibility of bound pairs formation in the normal state opening the pseudogap at high temperature is discussed briefly. The coexistence of bound pairs and the normal independent carriers for T _C < T < T_h could be the origin of the intrinsic inhomogeneity.     

Mathematical Simulation of Radiation Instability and a Possible Method of Taking Instability into Account in Realization of the Unit of Power of Laser Radiation and Dissemination of the Unit of Power

The present study is devoted to mathematical simulation of the instability of laser radiation. An algorithm for establishing the shape of continuous laser radiation received at the input of a measuring system is presented.     

Microstructure of Nanostructured WC-Co Coating Prepared by Thermal Spraying

Nanostructured WC-Co coatings were produced with Atmospheric Plasma Spraying (APS) and Low Pressure Plasma Spraying (LPPS). Microstructure characteristics and phase compositions of the coatings were studied by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD) respectively. The microstructure compositions were analyzed with EDS. During APS deposition the existence of oxygen causes the decarburization of the coating, and the coating was composed of melted area and the WC/12Co powder. Besides WC phase, there was W2C phase. However in the coating deposited by LPPS the content of oxygen was so low that there were a limit degradation of the WC/12Co powder. The coatings were made up of compact block and loosen porosity area. There were large quantities of nanostructure WC grains and a small quantity of microstructure WC grains presented in the coating. Besides WC phase, a little W2C and WC1-x or Co6W6C phases occured. Consideration of the characteristics of the highly porous, spherical-shell morphology of nano-WC/12Co power, heterogeneous melting and localized superheating of the power were two main factors which caused the microstructure and phase composition of nano-WC-Co coatings.     

Effect of Magnetic Field on the Deposition of Transparent Diamond-Like Carbon ( DLC ) Films by RF-PCVD

In order to deposit transparent and hard DLC films, magnetic field was introduced to enhance the plasma density of radiofrequency plasma chemical vapor deposition (RF-PCVD). In this paper, the configuration and computation of external magnetic field B are introduced. The restriction effect of magnetic field B on the charged particles and the effect of magnetic field B on the primary parameters-nonindependent power Pf and self-bias Uz were also studied. The mechanism of how magnetic field B affects self-bias Uz was analyzed.     

Axial power flow distributions of ultrasonic guided waves in viscous liquid-filled pipes

The axial power flow (APF) magnitude and attenuation distributions of ultrasonic longitudinal guided waves in viscous liquid-filled elastic pipes are investigated. The optimal location, optimal mode and its frequency-thickness product (fd) for the test of pipes filled with viscous liquid are chosen according to APF and attenuation distributions. The results show that the APF magnitude distribution is an important parameter in choosing the modes and parameters. A particular mode has weak dispersion in ranges of fd values with large group velocity, while other modes with smaller group velocity in the same fd ranges have stronger dispersion. It has been observed that, within these ranges, the chosen mode has a larger APF on the pipe's wall. Therefore, in the region of fd values where a particular mode has a large group velocity, this mode will be effective to be used in testing elastic pipes filled with viscous liquid. The results obtained from both the APF analysis and attenuation distribution are consistent.     

莱钢创建学习型企业实践

莱钢在学习型企业创建过程中，通过建立团队学习、注重能力培养、将工作与学习相融合、形成培训立体网络，解决了发展能力问题；为释放职工潜能，莱钢积极倡导自省、号召挑战传统和极限，解决了发展动力问题；通过系统思考，解决了发展过程中的瓶颈和重大改革问题，提升了企业的核心竞争力。     

降低供电系统线损提高电能利用率

本文通过对线损的概念、产生原因、如何计算进行阐述,从技术降损和管理线损两个方面提出了降低线损的措施,使线损率长期保持在4%以下,提高了电能利用率。     

加强综合管理降低生产电耗

本文对矿山生产的特点进行了分析,找到了生产能源消耗高的原因,通过加强综合管理,取得了明显的经济效益。     

宝钢马迹山港供电系统无功补偿分析

针对宝钢马迹山港原供电系统功率因数低下的问题，提出了一种新的无功补偿容量计算方法。此方法结合TCR FC的补偿方案，成功实现了该供电系统在冲击性负荷下功率因数大于0．9的目标。