Study of Hydrometallurgical Purification Unit for Preparing Solar-Grade Silicon with Metallurgical Route

湿法提纯作为冶金法路线制备太阳能级硅的前处理工序,可以去除大部分金属杂质,提高最终产品收率。考察了硅粉粒径、浸出剂浓度、温度、时间、搅拌等因素的影响,采用ICP、SEM等对产品进行了表征。当工艺条件为:硅粉平均粒径44μM、W(HCl)=5%、温度80℃、时间6H,处理后产品中杂质W(fE)=2.4x10-5,去除率为99.2%,杂质W(Al)=6.4x10-5,去除率为80%。描述了酸浸过程在前后不同阶段分别为受反应速度和内扩散控制历程。为太阳能级硅制备工业化开发,大幅度降低成本提供了参考。As a pre-treatment unit for preparing solar-grade silicon(SG-Si),hydrometallurgical route could remove most metallic impurities in metallurgical-grade silicon(MG-Si)and raise the final product yield.Factors such as the particle size of silicon,the mass fraction of leaching agent,temperature,time,and stirring were investigated,and the samples were characterized by ICP,SEM,etc.When MG-Si powder had been leached at appropriate conditions:the average size of silicon powder particle 44 μm,the mass fraction of hydrochloric acid 5%,reaction temperature 80 ℃,reaction time 6 h.It was found that 99.2% of Fe impurity and 80% of Al impurity in MG-Si powder were removed.The final Fe and Al impurities mass fraction could be reduced to 2.4×10-5 and 6.4×10-5 respectively.The leaching process was controlled by reaction rates and internal diffusions at different stages.The experimental results provided the reference to reduce the cost of industrialized development for preparing SG-Si

可重构力学超材料的设计与波动特性研究

力学超材料中的弯曲梁双稳态结构由于其主动调控性强且调控精度高等优点近年来受到广泛关注.文章利用中心受压弯曲梁的不稳定性设计了六角型双稳态结构,首先建立了等效弯曲梁模型,基于梁变形微分方程及能量最低原理探明了结构双稳态特性的产生基理,之后利用有限元数值计算研究了结构几何参数对其整体力学性能的影响,分别得到了具备自恢复及双稳态性能的结构几何参数范围,绘制了几何参数与力学性能之间的相图.同时,可重构结构的可控变形能力有助于调整整体的色散特性,利用数值仿真研究了具备双稳态特性的结构在拉伸和压缩两种构型下的色散关系,对比分析了不同结构几何参数及构型转变对结构产生的带隙位置及范围的影响,之后对由不同构型单胞组成的周期性结构进行了频响分析来验证带隙计算的准确性.通过六角型可重构结构的力学特性、色散特性研究及频响分析表明可以通过结构几何参数的设计实现对结构整体性能的主动调控,为可逆向设计的弹性波超材料结构研究分析提供了一条可靠路径

Preparation and Electrochemical Behavior of Li_4Ti_5O_(12) Nanosheets as Anode Material for Lithium Ion Battery

以无定形的水合二氧化钛为前驱物,水热法合成了200～400nm大小的Li4Ti5O12纳米片作为锂离子电池负极材料.XRD(X射线衍射)、SEM(扫描电子显微镜)和TEM(透射电镜)分析表征样品的物相结构、表观形貌;循环伏安、充放电循环和电化学交流阻抗技术分别测定该纳米Li4Ti5O12在有机电解液和室温离子液体S114TFSI电解液中的电化学性能.结果表明,该材料具有较高的放电容量和良好的循环性能,有望成为锂二次电池新型负极材料.Spinel lithium titanate(Li4Ti5O12) nanosheets with a size range of 200 ～400 nm were synthesized by hydrothermal process from the amorphous hydrous titanium oxide precursors.The as-prepared products were characterized by X-ray powder diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The electrochemical behaviors of Li4Ti5O12 electrode in conventional organic electrolyte and ionic liquid electrolyte were investigated by using cyclic voltammetry,galvanostatic charge-discharge and AC impedance techniques.The experimental results indicate that the as-prepared nanostructured Li4Ti5O12,evaluated as anode material,exhibited good reversibility and cycle performance.It is expected to be a potential anode material for commerical battery applications.作者联系地址：上海交通大学化学化工学院;Author's Address: School of Chemistry and Chemical Technology,Shanghai Jiao Tong University,Shanghai 200240,Chin

农田病虫害监测预警数据自动采集技术

研发微小昆虫自动计数系统和植物叶面分析系统,实现了在田间抽样过程中对农田害虫种群动态的自动监测和对作物叶面积的自动测量及叶面病害症状的形态分析。集成传感器、单片机和无线通讯技术研发了农田小气候数据采集系统,在此基础上进一步将作物管理专家系统软件植入单片机,推出温室作物生态健康智能监护系统;它们实现了对田间小气候的自动监测

Postoperative nursing of a patient with lumbar disc herniation (1例腰椎间盘突出症患者的术后护理体会)

This paper summarized the postoperative nursing of a patient undergoing surgery for lumbar disc herniation. Based on the comprehensive nursing assessment and analysis of key nursing issues, targeted nursing interventions including pain control, dietary guidance, catheter maintenance, postoperative functional exercise and prevention of complications were carried out to improve the recovery of the patient. (本文总结1例腰椎间盘突出症患者的术后护理体会。在完善术后护理评估的基础上, 明确护理问题并制定护理计划, 实施针对性护理措施, 包括疼痛控制、饮食指导、管路维护、术后功能锻炼和并发症预防, 促进患者康复。

Postoperative nursing of a patient with cervical spondylotic myelopathy (1例脊髓型颈椎病患者的术后护理体会)

This paper summarized the postoperative nursing measures for a patient with cervical spondylotic myelopathy. Based on the postoperative nursing assessment, interventions such as pain control, gastrointestinal function care, airway management were carried out. Traditional Chinese Medicine nursing techniques including intradermal needling, auricular acupoint pressing, Chinese herbal medicine hot-compress, external application and fumigation were conducted under the guidance of syndrome differentiation. The nursing of integrated traditional Chinese and western medicine is effective to relieve the pain, improve the gastrointestinal function and prevent the postoperative complications. (本文总结1例脊髓型颈椎病患者术后护理经验。基于术后护理评估, 实施疼痛干预、胃肠道功能干预、呼吸系统管理等护理措施。在常规护理的基础上, 通过辨证施护, 开展皮内针、耳穴压丸、中药热奄包、药膏涂擦及熏蒸等中医适宜护理技术。中西医结合护理干预能够有效减轻患者疼痛, 改善胃肠道功能, 预防并发症。