Calculation of AC Losses of CICC for Superconducting Outsert Coils in a Hybrid Magnet

This paper is devoted to predict AC loss of Cable in Conduit Conductor (CICC) which is of importance in the design of conductors. The consideration for the conductor’s design and main parameters for the magnets are introduced. In order to attain a good accuracy in the calculation of AC losses, the field distribution within superconducting outsert should be considered. Calculation of the AC losses, including hysteresis losses and coupling losses, is conducted. An emphasis is put on the hysteresis loss during the ramp up of the current to the operational current (15.3 kA) and the coupling loss of the conductor in a power-down condition for insert. The results are obtained to be 74.9kJ and 950J for 40 T hybrid magnets, respectively. Based on the calculation, a brief analysis of losses effect on the conductor design and the operation of magnet is given for the purpose that the capacity of the cryogenertor can be evaluated and the stability regime can be improved in our future work on the hybrid magnets.     

Mechanism of Phase Transition from Liquid to Gas under Dielectric Barrier Discharge Plasma

Liquid gasification phenomenon was observable in liquid-solid dielectric barrier discharge (DBD) experiments. Starting from classical thermodynamics, this study aimed at finding the reason of liquid gasification in the DBD experiments. Fluid statics and electrohydrodynamics were adopted to analyze the mechanism of phase transition from liquid to gas. The Sumoto effect was also employed to visually explain the change in the pressure of fluid due to the electric field. It was concluded from both theoretical analysis and experiment that the change in liquid pressure was a key factor causing liquid to gasify in DBD conditions. Furthermore, it was stressed that the liquid pressure was affected by many parameters including liquid permittivity, voltage, electric intensity, size of the discharge space and uniformity of the electric field distribution, etc. All of them affected DBD liquid gasification. The related results would provide useful theoretical evidence for multi- phase DBD applications.     

Surface Modification of Polypropylene Microporous Membrane by Atmospheric- Pressure Plasma Immobilization of N,N-dimethylamino ethyl methacrylate

Surface modification of polypropylene microporous membrane (PPMM) was performed by atmospheric pressure dielectric barrier discharge plasma immobilization of N,N-dimethylamino ethyl methacrylate (DMAEMA). Structural and morphological changes on the membrane surface were characterized by attenuated total reflection-Fourier transform infrared spectroscopy (FT-IR/ATR), X-ray photoelectron spectroscope (XPS) and field emission scanning electron microscopy (FE-SEM). Water contact angles of the membrane surfaces were also measured by the sessile drop method. Results reveal that both the plasma-treating conditions and the adsorbed DMAEMA amount have remarkable effects on the immobilization degree of DMAEMA. Peroxide determination by 1,1-diphenyl-2-picrvlhydrazyl (DPPH) method verifies the exsistence of radicals induced by plasma, which activize the immobilization reaction. Pure water contact angle on the membrane surface decreased with the increase of DMAEMA immobilization degree, which indicates an enhanced hydrophilicity for the modified membranes. The effects of immobilization degrees on pure water fluxes were also measured. It is shown that pure water fluxes first increased with immobilization degree and then decreased. Finally, permeation of bovine serum albumin (BSA) and lysozyme solution were measured to evaluate the antifouling property of the DMAEMA-modified membranes, from which it is shown that both hydrophilicity and electrostatic repulsion are beneficial for membrane antifouling. Key words: polypropylene microporous membrane, DMAEMA, atmospheric-pressure plasma, immobilization, antifouling     

Experimental Study of the Effect of Applied Magnetic Field on Plasma Properties of Unbalanced Magnetron Sputtering

An experimental study of the effect of applied magnetic field on the properties of the plasma and electrostatic oscillations in an unbalanced magnetron sputtering discharge was carried out. The apparatus consists of a magnetron sputtering target, using the conventional magnetic field configuration, and a coaxial coil around the target for an applied axial magnetic field. The dependencies of plasma parameters on the coil current were studied by two Langmuir probes. The resonance properties of electrostatic oscillations were observed. The results indicate that the applied magnetic field affects the plasma properties for the coil current in a range of 0 to 8 A. The frequency bandwidth of the electrostatic oscillations in the unbalanced magnetron sputtering plasma is in a range of 0 to 300 kHz. From the spectrum analysis, the eigenfrequency near the target is in a range of 20 to 50 kHz under typical experimental conditions where all the magnetic field, pressure, and power etc are able to have full impact on the spectrum characteristics. The calculated value of the electron temperature as per an ion acoustic standing wave pattern inside the magnetic trap is in good agreement with the experimental result.     

矿井下无轨胶轮车的现状及应用研究

无轨胶轮车在矿井中的使用逐渐受到人们的重视，其结构简单、运载能力强，使得无轨胶轮车在逐渐向无轨化、单一化发展，彻底解决了有轨运输时运输效率差、运输麻烦的问题。分析了无轨胶轮车的特点，并以古城煤矿建设管理处无轨胶轮车设备选型配备为例，研究了无轨胶轮车设备选型配备问题，介绍了我国无轨胶轮车发展中遇见的问题以及无轨胶轮车的具体使用情况，研究为我国矿井无轨胶轮车的发展提供了理论基础。     

KNO3-H2O溶液间歇结晶动力学

基于ΔL定律推导了晶体线性生长速率的数学表达式,利用已建立的溶液间歇结晶动力学实验研究手段实现了溶液透光率和浓度的在线测量.利用经验模型关联线性生长速率和相对过饱和度求取了生长动力学参数,并与文献值进行了比较.结果发现：对于自发成核结晶过程,综合动态透光率、过饱和度和经验模型可对成核和生长阶段进行定性识别.     

矿井瓦斯涌出风险态势分析平台研究

为了更好地实现煤矿瓦斯治理及瓦斯涌出风险超前预警,在井下使用不同类型的监控系统数据采集接口来收集原始数据,利用小波理论对数据进行处理,以获得有效数据。对采掘面瓦斯涌出的外在表现、涌出正常特征、涌出异常特征、影响工作面瓦斯涌出因素进行了分析,同时也研究了采掘面风流中的瓦斯分布规律,确定了井下工作面甲烷传感器悬挂的最佳巷道位置。由此得到的监测数据更能真实地反映瓦斯涌出量,便于更好地掌握瓦斯涌出的影响因素,更有效地进行工作面前方的瓦斯灾害或瓦斯超限的预测预报。矿井瓦斯涌出风险态势分析平台就是基于上述理念研究设计的,该平台能够实现数据存储、查询、分析、计算、参数录入等功能,为矿井瓦斯防治工作提供有效的参考。     

神经网络建模方法在维生素C发酵过程中的应用

传统的标准“黑箱”型人工神经网络已较为广泛地应用于生化过程中的状态预估等多个方面,然而结合过程先验知识或部分机理模型的混合神经网络建模方法能给出更令人满意的结果.本文将其应用于2-酮基-l-古龙酸（2-KLG）发酵过程的状态估计,并将其结果与传统神经网络模型进行了比较,混合模型明显优于单一神经网络方法.     

Web-based Logbook System for EAST Experiments

Implementation of a web-based logbook system on EAST is introduced,which can store the comments for the experiments into a database and access the documents via various web browsers. The three-tier software architecture and asynchronous access technology are adopted to improve the system effectively. Authorized users can view the information of real-time discharge, comments from others and signal plots; add, delete, or revise their own comments; search signal data or comments under complicated search conditions; and collect relevant information and output it to an excel file. The web pages can be automatically updated after a new discharge is completed and without refreshment.     

苄青霉素盐结晶过程

本文研究了β-内酰胺类抗菌素药物真空闪蒸结晶过程．以苄青霉素钾盐为例,测定了该物系的结晶热力学相图与介稳区曲线,应用间歇动态法确定了该物系的结晶动力学参数,进而求取了最佳操作时间表.