Sonochemical synthesis of nanostructured nickel hydroxide as an electrode material for improved electrochemical energy storage application

A facile and fast approach for the synthesis of a nanostructured nickel hydroxide(Ni(OH)_2) via sonochemical technique is reported in the present study. The X-ray diffraction results confirmed that the synthesized Ni(OH)_2 was oriented in β-phase of hexagonal brucite structure. The nanostructured Ni(OH)_2 electrode exhibited the maximum specific capacitance of 1256 F/g at a current density of 200 mA/g in 1 M KOH_((aq)). Ni(OH)_2 electrodes exhibited the pseudocapacitive behavior due to the presence of redox reaction. It also exhibited long-term cyclic stability of 85% after 2000 cycles, suggesting that the nanostructured Ni(OH)_2 electrode will play a promising role for high performance supercapacitor application.     

浅议新疆电子档案与纸质档案的并存管理

随着新疆办公自动化、网络化、智能化的发展,给档案工作也带来了巨大的冲击,电子档案的出现对纸质档案产生了深刻的影响。就此对新疆电子档案与纸质档案工作现状进行了比较分析,总结了新疆档案并存管理的途径。说明了电子档案与纸质档案之间是一种相互促进、相互补充不可相互替代的关系,从而得出了电子档案与纸质档案在相当长的一个时期内是并存的关系,它们将各自发挥各自的优势。     

购买爵位 土豪如何快速变身贵族?

正中国已经移民的土豪们要想成为贵族其实有一条捷径——那就是像基督山一样买个"伯爵"称号。玛莎拉蒂首发款、来自威兹曼限量版敞篷跑车、世界最大的紫檀餐桌、瑞士波尔宝马手表、南非、斯里兰卡等矿区直运的顶级钻石宝石等,这就是2013年12月12日在北京举行的国际顶级私人物品展展出的一些昂贵物件。这些奢侈品的亮相进一步表明,中国富豪已经变得越来越富有,而且更有国际经验,现在的欧美冒出了不少旨在迎合中国超级富翁口味的公司,从私密社交俱乐部"亲和中国"咨询公司到会员制网络社区,总有聪明的企业家诱导充满幻想、超级富有而又有点不切实际的中国人去购买他们的西方梦,而成为贵族也是这个西方梦的一部分。欧洲有一句谚语:三天培养出一个富翁,三代培养     

Studies on induction hardening of powder-metallurgy-processed Fe-Cr/Mo alloys

Induction hardening of dense Fe-Cr/Mo alloys processed via the powder-metallurgy route was studied. The Fe-3Cr-0.5Mo, Fe-1.5Cr-0.2Mo, and Fe-0.85Mo pre-alloyed powders were mixed with 0.4wt%, 0.6wt%, and 0.8wt% C and compacted at 500, 600, and 700 MPa, respectively. The compacts were sintered at 1473 K for 1 h and then cooled at 6 K/min. Ferrite with pearlite was mostly observed in the sintered alloys with 0.4wt% C, whereas a carbide network was also present in the alloys with 0.8wt% C. Graphite at prior particle boundaries led to deterioration of the mechanical properties of alloys with 0.8wt% C, whereas no significant induction hardening was achieved in alloys with 0.4wt% C. Among the investigated samples, alloys with 0.6wt% C exhibited the highest strength and ductility and were found to be suitable for induction hardening. The hardening was carried out at a frequency of 2.0 kHz for 2-3 s. A case depth of 2.5 mm was achieved while maintaining the bulk (interior) hardness of approximately HV 230. A martensitic structure was observed on the outer periphery of the samples. The hardness varied from HV 600 to HV 375 from the sample surface to the interior of the case hardened region. The best combination of properties and hardening depth was achieved in case of the Fe-1.5Cr-0.2Mo alloy with 0.6wt% C.     

基于C51单片机课程教学的探索

单片机课程具有较强的综合性与实践性,是高校众多专业的必修课之一。针对传统的单片机课程教学的特点,对单片机理论内容进行了重组,提出了实时动态演示教学方法与项目式教学法,实践表明,教学效果良好。     

Effect of retained austenite and nonmetallic inclusions on the thermal/electrical properties and resistance spot welding nuggets of Si-containing TRIP steels

Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets. Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JMatPro? software. Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques. The nonmetallic inclusions were characterized by scanning electron microscopy. The results show that the contents of Si, C, Al, and Mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents. We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process. The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets.     

具有随机扰动强度的冲击预测模型

基于历史数据信息,提出了具有随机扰动强度的冲击预测模型.在预测步长大于和小于给定模型阶数的情况下,分别给出了冲击强度未来n步的估计值Y_(t+n)|Y_t,Y_(t-1),….在正态假设下,推导出预测值置信水平为1-α的置信区间.     

基于C8051F的多通道模数转换系统的设计与应用

以Silicon Labs公司研发设计的C8051F020芯片为核心,详细剖析了该芯片的12位SAR ADC0模数转换模块,并在Keil uVision4和visual c++6.0环境中实现了仿真模拟.为了在仿真系统中更清晰明了地展现仿真结果,本系统使用UART接口,将仿真结果传输到上位机进行显示.     

新时期教学目的著作权合理使用的实施困境与解决对策

【目的】分析新时期教学目的著作权合理使用的实施困境，提出解决对策。【方法】以教学目的著作权合理使用为研究对象，对比国外相关规定，分析总结我国教学目的著作权合理使用存在的困境。【结果】“课堂教学”的规定难以适应时代的发展，严格限定的合理使用的方式不能满足现代教学需要，合理使用的人员范围不明。【结论】为解决以上困境，需扩大对“课堂教学”的解释，扩充合理使用的方式，进一步明确合理使用的主体，凡从事非营利性教学活动的学校及其他教育机构均可以成为合理使用人，教育对象也应被纳入合理使用的人员范围。