Technical Note and Brief Overview of the Materials Science and Technology along with Designing Aspects for Development of Spintronic Devices with Optimum Efficiency

One of the major challenges in designing and fabricating Spintronic devices is the choice of both, Materials and the Technology, along with understanding the intricacies of the Designing aspects. In this communication, we have attempted to briefly discuss these factors, with an aim to draw the attention of the Materials Scientists and Technologists to this serious challenge, in the direction of which, though a lot of research and development work has been done, still needs more concerted efforts to be made in order to make the Spintronic devices that can offer good efficiency for maximizing their usefulness.

Gunn器件中畴的静止-渡越-静止模式的实验观察和计算机模拟

本文讨论在GaAs n^+-n-n^+夹层结构的Cunn器件中畴的静止-渡越-静止模式,进行了实验观察和计算机模拟,指出在超过阈值的偏置电压下,当畴的耗尽层进入阳极附近的高掺杂区后,会逐渐停止下来形成准静态畴,这时畴外电场达到最大值.如果这时阴极凹口仍不能形成新畴,则准静态畴将进一步调整成为真正的静止畴,而畴外电场也将由最大值下降到一个与偏压无关的固定值.经过理论分析,得到了静止畴所固有的与外加偏压无关的畴外电场与有源区掺杂浓度的关系式,并和计算机模拟的结果相比较,得到很好的符合.如果偏压的增加使准静态畴所对应的畴外电场最大值已经足够使阴极凹口形成新的畴,则静止畴将转变为渡越畴.如果偏压继续增加,使积累层尾部覆盖了阴极凹口,则畴会再次静止下来,直到偏压增加到畴发生雪崩为止.计算和实验表明,后一个静止区的电压变化范围要比前一个大得多.本文还讨论了两个转变电压和温度的关系及扩散系数对静止畴的影响.

橙红色磷光铱配合物的合成及其性能

合成并表征了配体为苯并噻唑衍生物的2种新型铱配合物,三[N,N-二(4甲苯基)-4-(2-苯并噻唑基)苯胺]合铱(Ir(bpmp)3)和三[N,N-二苯基-4(-2-苯并噻唑基)苯胺]合铱(Ir(bpp)3)。以铱配合物Ir(bpmp)3作为发光层,以聚(3,4亚乙氧基噻吩)(PEDOT)为空穴传输层制备结构为ITO/PEDOT/Ir(bpmp)3/Ca/Al的发光器件,当驱动电压为5V时,可观察到橙红色磷光,最大发射波长在550～650nm之间。当驱动电压为19V时,最大发光亮度为20cd/m2。最大外功率效率仅为9×10-4lm/W,最大电流效率仅为4×10-3cd/A。外功率效率和电流效率极低的原因是由于将Ir(bpmp)3直接当作磷光发光层,导致严重的三线态-三线态淬灭以及浓度淬灭。

Open Surgery for Retrieval of Patent Foramen Ovale Closure Device Embolized into Right Pulmonary Artery

Percutaneous Patent Foramen Ovate PFO/Atrial Septal Defect (ASD) closure has become an increasingly simplified procedure over the past decade. The main advantages of a percutaneous approach include avoidance of surgery, short procedure time and hospital stay. Device embolization is seen rarely but it can be fatal. We report this complication following a percutaneous PFO closure in a 44-year-old man. The device was embolized into the distal part of the right pulmonary artery. We removed the device surgically and closed the PFO/ASD.

A METHOD IN SYSTEM DESIGN OF EJECTING DEVICES OF MISSILES

Anew method in system design of ejecting devices of missiles is first presented.Some important points are dis-cussed,which guid the research and development of new ejecting devices of missileg,amd provid the foundation flr thw design of mew ejecting device is provided.The system design includes the distribution of techmology specifica-tion,3-D solid modeling of ejecting devices of missiles im-ported from abroad,the design of pmeumatic device sys-tem,the design of ejecting mechanism system,the predic-tion of reliability and the experimental analysis,etc.

Investigation of Working Bodies of the Device for Separation of Fibers Suitable for Spinning from Cotton Waste

It is known that fiber wastes (lint, down and seeds) produced at ginneries contain fibers that are suitable for spinning and can be used in industry, and their separation significantly increases the level of fiber production (1.9% - 2.5%). Based on these analyzes, the study aimed to create a new device that separates long fibers from lint and down. As a result, the amount of fiber output in the enterprise will increase and the enterprise will have significant economic benefits. In addition, the introduction of the device will prevent the addition of long fibers (longer than 16 mm) that can be used in the textile industry to the waste. This article focuses on the creation of a fiber separation device suitable for the treatment and spinning of fibrous waste produced in ginneries. The study theoretically examined the main working bodies of the fiber separation device from waste. Theoretical research is devoted to the study of the strength of the main working body of the fiber separation device−the separating saw drum and its shaft. In the study, the sawdust drum is a more stressed steel coating, and it was found that the strength reserve of this drum is [δТ] = 2.03 (where δТ = 0.8 - 2.5) was found to be. As a result of calculating the resistance of the saw drum shaft to stiffness and vibration, it was determined that the shafts are resistant to vibration under periodic loading and that the oscillation frequency along its axis through the critical rotation frequency is vcr=10.3 Gts.

利用硫化碱废渣制备新型多功能悬浮型种衣剂的研究与应用(Ⅰ)——新型多功能悬浮型种衣剂的研究

本文研究了以工业硫化碱废渣与一类丰富的废弃矿物质等为原料,合成新型阴离子表面活性剂--矽力康复合肥在悬浮型种衣剂中的应用,探讨了矽力康复合肥、不同种类的阴离子、非离子表面活性剂对20%的悬浮型种衣剂稳定性的作用及相互作用,确定了最佳复配条件.结果表明:在使用单一组分中,使用矽力康复合肥比其他9种表面活性剂的稳定性高20.2%～141.2%(15 d);在复配体系中,50g/L矽力康复合肥与15g/L乳化剂A复配体系在90 d后的悬浮率仍达到90.4%,比50g/L十二烷基苯磺酸钠与40g/L乳化剂A的复配体系高29%;产品粘度为500～600mpa·s、对种子的包衣均匀度为95.3%,成膜时间为19min,包衣脱落率为7.42%,热贮稳定性均符合标准,并且产品本身还含有大量促进种子生长的必要元素.

THE EFFECT OF THE CBN WHEEL DRESSING AND THE GRAIN HEIGHT PROTRUDING FROM THE BOND ON THE GRINDING PERFORMANCE

CBN (Cubic Boron Nitride) is a highly efficient abrasive and has unique properties (highhardness, high thermal stability and high chemical inertia). As early as 1969 CBN Wheels had al-ready been made and showed excellent performance for grainding high speed steels and othermaterials hard to be ground. So far, however, CBN Wheels are still not popularly utilized in theindustry, the writer considers the main reason being the inadequate study for practical applica-tions and especially the suitable dressing technique. The dressing of resinoid CBN Wheels discussed in the paper, is different from that ofconventional ones. It has to be divided into two operations, truing and sharpening, each of whichhas its specific and independent functions. A simple dressing method with a lot of informationsuitable for production is studied; finally, the grain height protruding from the bond is taken asan index for evaluating the dressing results, and the effect of grain height on the grinding per-formance is discussed. By selecting proper conditions according to the workpiece requirements, abetter technical and economical benifit can be obtained.

Measurement Process of MOSFET Device Parameters with VEE Pro Software for DP4T RF Switch

To design a Double-Pole Four-Throw (DP4T) RF switch, measurement of device parameters is required. In this DP4T RF switch CMOS is a unit cell, so with a thin oxide layer of thickness 628 ? which is measured optically. Some of the material parameters were found by the curve drawn between Capacitance versus Voltage (C-V) and Capacitance versus Frequency (C-F) with the application of Visual Engineering Environment Programming (VEE Pro). To perform the measurement processing at a distance, from the hazardous room, we use VEE Pro software. In this research, to acquire a fine result for RF MOSFET, we vary the voltage with minor increments and perform the measurements by vary the applying voltage from +5 V to –5 V and then back to +5 V again and then save this result in a data sheet with respect to temperature, voltage and frequency using this program. We have investigated the characteristics of RF MOSFET, which will be used for the wireless telecommunication systems.

A Literature Review: Potential Effects That Health Apps on Mobile Devices May Have on Patient Privacy and Confidentiality

Purpose: This research aims to evaluate the potential threats to patient privacy and confidentiality posed by mHealth applications on mobile devices. Methodology: A comprehensive literature review was conducted, selecting eighty-eight articles published over the past fifteen years. The study assessed data gathering and storage practices, regulatory adherence, legal structures, consent procedures, user education, and strategies to mitigate risks. Results: The findings reveal significant advancements in technologies designed to safeguard privacy and facilitate the widespread use of mHealth apps. However, persistent ethical issues related to privacy remain largely unchanged despite these technological strides.

用射流装置消除大型泵机组的汽蚀振动

一大型石化工程中乙烯乙二醇装置用碳酸盐泵投料运行后,泵机组和进出口管线就发生异常的噪声与振动现象,严重影响到生产安全和作业环境。笔者分析了异常噪声、振动的原因,认为是由于泵发生汽蚀所致;提出了在泵进口管线增设射流装置的措施,将泵自身出口的一部分高压液体引入到射流装置,并与来自储罐的液体混合,增加液体压头后提供给泵进口,以提高装置的有效汽蚀余量,消除大型泵机组由于汽蚀引起的噪声、振动;研讨了射流装置的设计参数和结构设计。通过增设射流装置的技术的措施,有效地解决了泵机组及进出口管线的异常噪声、振动问题,消除了化工系统的安全生产隐患。该技术措施还可以用于电厂等有类似问题的其他装置,有广泛的实用价值。

Self-adaptive PID controller of microwave drying rotary device tuning on-line by genetic algorithms

The control design, based on self-adaptive PID with genetic algorithms(GA) tuning on-line was investigated, for the temperature control of industrial microwave drying rotary device with the multi-layer(IMDRDWM) and with multivariable nonlinear interaction of microwave and materials. The conventional PID control strategy incorporated with optimization GA was put forward to maintain the optimum drying temperature in order to keep the moisture content below 1%, whose adaptation ability included the cost function of optimization GA according to the output change. Simulations on five different industrial process models and practical temperature process control system for selenium-enriched slag drying intensively by using IMDRDWM were carried out systematically, indicating the reliability and effectiveness of control design. The parameters of proposed control design are all on-line implemented without iterative predictive calculations, and the closed-loop system stability is guaranteed, which makes the developed scheme simpler in its synthesis and application, providing the practical guidelines for the control implementation and the parameter design.

振荡型波浪能转换装置中两种优化方法研究

该文基于线性波理论,从载体在波浪中的运动方程出发,以两种不同的优化角度推导了波能装置输出能量最大时的表现形式,最后以圆柱体作为波浪能转换的载体分析了两者方法的差异。数值计算表明在同一水深下,波能装置浮体的水线面决定了波能装置最优转换效率的趋势,而吃水深度决定了波能装置可达到的最大转换效率;对波能装置参数优化后运动在共振点的波能装置其转换效率并不是最大,而优化后的最大转换效率并不发生在共振点上。

Optimized cardiac magnetic resonance imaging inversion recovery sequence for metal artifact reduction and accurate myocardial scar assessment in patients with cardiac implantable electronic devices

Late gadolinium enhancement(LGE) cardiovascular magnetic resonance(CMR) is the gold standard for imaging myocardial viability.An important application of LGE CMR is the assessment of the location and extent of the myocardial scar in patients with ventricular tachycardia(VT), which allows for more accurate identification of the ablation targets.However, a large percentage of patients with VT have cardiac implantable electronic devices(CIEDs), which is a relative contraindication for cardiac magnetic resonance imaging due to safety and image artifact concerns.Previous studies showed that these patients can be safely scanned on 1.5 T scanners provided that an adequate imaging protocol is adopted.Nevertheless, imaging patients with a CIED result in metal artifacts due to the strong frequency off-resonance effects near the device; therefore, the spins in the surrounding myocardium are not completely inverted, and thus give rise to hyperintensity artifacts.These artifacts obscure the myocardial scar tissue and limit the ability to study the correlation between the myocardial scar structure and the electro-anatomical map during catheter ablation.In this study, we developed a modified inversion recovery technique to alleviate the CIED-induced metal artifacts and improve the diagnostic image quality of LGE images in patients with CIEDs without increasing scan time or requiring additional hardware.The developed technique was tested in phantom experiments and in vivo scans, which showed its capability for suppressing the hyperintensity artifacts without compromising myocardium nulling in the resulting LGE images.

高功率毫米波辐照对秀丽线虫行为学和细胞形态学的影响

采用角锥喇叭天线,使用不同输出平均功率的毫米波激光辐照秀丽线虫,采用实时显微摄像系统记录线虫行为学变化,并使用体视显微镜观察线虫细胞形态学变化。受照射后自由活动的秀丽线虫能够快速逃离高功率毫米波的辐照区域。当受输出平均功率为10 W和12 W辐照后,线虫先后出现运动速度增加、运动速度减慢直至身体僵直不动的变化过程。当输出平均功率为5 W时,线虫出现热耐受现象。细胞形态学观察结果显示:辐照后的线虫腹中卵细胞核结构出现不同程度的异常。高功率毫米波辐照可显著影响线虫的行为学特征及细胞形态学,同时说明秀丽线虫是可适用于高功率毫米波生物效应研究的模式生物之一。

An Analysis on Position Estimation, Drifting and Accumulated Error Accuracy during 3D Tracking in Electronic Handheld Devices

This work focuses on a brief discussion of new concepts of using smartphone sensors for 3D painting in virtual or augmented reality. Motivation of this research comes from the idea of using different types of sensors which exist in our smartphones such as accelerometer, gyroscope, magnetometer etc. to track the position for painting in virtual reality, like Google Tilt Brush, but cost effectively. Research studies till date on estimating position and localization and tracking have been thoroughly reviewed to find the appropriate algorithm which will provide accurate result with minimum drift error. Sensor fusion, Inertial Measurement Unit (IMU), MEMS inertial sensor, Kalman filter based global translational localization systems are studied. It is observed, prevailing approaches consist issues such as stability, random bias drift, noisy acceleration output, position estimation error, robustness or accuracy, cost effectiveness etc. Moreover, issues with motions that do not follow laws of physics, bandwidth, restrictive nature of assumptions, scale optimization for large space are noticed as well. Advantages of such smartphone sensor based position estimation approaches include, less memory demand, very fast operation, making them well suited for real time problems and embedded systems. Being independent of the size of the system, they can work effectively for high dimensional systems as well. Through study of these approaches it is observed, extended Kalman filter gives the highest accuracy with reduced requirement of excess hardware during tracking. It renders better and faster result when used in accelerometer sensor. With the aid of various software, error accuracy can be increased further as well.

Design of the Control System of Adaptive Balancing Device Based on PLC

Due to the well condition and the un-expected imbalance movement of the pumping unit in use, the energy consumes a lot. The existing balancing equipment cannot adjust and monitor the pumping units in real time. Therefore this paper introduces the new adaptive balancing equipment—fan-shaped adaptive balancing intelligent device, projects a design of such control system based on PLC, and determines the principle of the control system, the execution software and the design flow. Site commissioning effect on Daqing Oilfield shows this fan-shaped adaptive balancing intelligent device can effectively adjust and monitor the pumping unit in real time, the balance even adjusts from 0.787 to 0.901, and integrated energy saving rate is 14.2%. It is approved that this control device is professionally designed, with strong compatibility, and high reliability.

广东交直流混合电网的运行稳定性研究

建立了包含广东220kV及以上电压等级系统和主要互联省网等值系统的详细机电暂态仿真模型,在BPA平台上对2005年处于多回直流馈入交直流混合运行状态的广东电网的运行稳定性问题进行了全面测算和分析。通过计算广东电网的各逆变站在不同运行方式下的短路比分析了广东电网作为直流受端系统的强度。通过负荷中心附近发生单重和多重故障时的暂态稳定计算,分析了多个逆变站同时发生换相失败的可能性及其对广东电网安全稳定性的影响。通过区内外多重故障后果的对比分析,指出了广东电网的薄弱环节,并提出了相应的控制对策。

Determination of Technological Parameters of Fiber Separation Device from Cotton Waste

This article examines the technological parameters of the device for the separation of fibers suitable for spinning by processing fibrous waste from the technological processes of ginneries. Technological processes in the cotton ginning industry include a complex of physical and mechanical advantages, the successful study of which is possible only with the use of modern achievements in science and technology. Therefore, it is advisable to conduct scientific research based on mathematical modeling. To justify the effective operation of the selected design of the cotton fiber separation device, it is necessary to select its optimal technological parameters. Improving the efficiency of the process of separation of spinning fibers from the composition of fibrous waste depends directly on technological parameters. The application of mathematical methods in the planning and conduct of research allows for determining the individual effects of the interaction of several factors that characterize the combined parameters of the optimization parameters, in contrast to traditional computational methods of research. As a result, it will be possible to obtain a mathematical model of the object understudy in a relatively small number of tests, which will simultaneously serve to obtain optimal solutions.

倒装芯片互连技术在光电子器件封装中的应用

分析了倒装芯片技术在光电子器件封装中应用时对基板和焊料的性能要求,在硅基板上设计和制作了用于激光芯片和光电探测器贴片的焊料凸点结构,并应用全自动贴片设备进行了贴片工艺试验.试验结果表明,倒装芯片技术可实现芯片与基板的高精度、高可靠性的互连,这种技术用于光收发器件的封装,可实现光电子器件的小型化和批量化生产,并能大大提高光收发模块的传输速率.