激光光束质量因子的研究进展

本文详细分析了各种光场下光束质量M2因子。在不同的场中,A.E.Siegman当初所定义的M2因子,已经有了很大的变化,因而M2因子的特性也与当初不同,不仅M2因子可以大于等于1,而且可以小于1,甚至小于0。其反映的物理意义,也从经典场中的衍射极限倍数,变化为非经典场中的准直性量度以及对空间相干性的某些反映。此外还列举并分析了几种特殊的光束质量因子,最后讨论了M2因子应用的问题并指出了其局限性。     

Study on heat conduction and adsorption/desorption characteristic of MIL-101/few layer graphene composite

Journal of Porous Materials - Aiming at the poor heat conduction performance of porous MIL-101 applied in adsorption cooling process, few layer graphene (FLG) was selected as a promising thermal...     

Adsorption characteristics of hexadecyl ammonium with different numbers of carbon chains in montmorillonite and the structure of the prepared composites

Journal of Porous Materials - The dynamics and thermodynamics of adsorption of hexadecyl ammonium with different numbers of carbon chains in montmorillonite (Mt) with different layer charge density...     

含多端口能量路由器的多能互补系统故障保护功能测试研究

针对某区域用电负荷存在严重的季节性过载现象,以及可再生能源存在功率波动大、稳定性较差的问题,研制了多能(含水电、光伏、储能)、多端口的能量路由器装置及其能量管理系统.综合考虑当地多场景运行,解决了季节性过载问题,实现了能量的合理配置与利用.首先,对比分析选定能量路由器各端口变换器的拓扑结构;然后,对多场景下的工作模式进行介绍;最后,对含能量路由器的多能互补系统进行故障保护功能测试.测试结果表明,该系统具有较好的故障保护功能,有效实现了不同场景下的工作模式切换,直流母线电压稳定以及上层功率指令跟踪等功能,解决了当地用电负荷季节性过载和可再生能源功率波动较大的问题.     

苦参生物碱杀虫生物活性测定

以桃蚜等9种试虫为供试靶标，研究了苦参根提取物和苦参碱、氧化苦参碱、槐果碱、野靛碱的杀虫活性。试验结果表明：苦参生物碱具有一定的杀虫活性，9种试虫中，苦参根提取物对蚜虫的活性最高，其对蚕豆蚜的LC50为20．635mg／L；即使在最高剂量为4000mg/L时，也不能直接杀死粘虫、小菜蛾和棉铃虫。4种生物碱对朱砂叶螨活性均较低，LC50均大于2500mg／L。野靛碱是4种生物碱中杀虫活性最高的，对淡色库蚊、桃蚜、蚕豆蚜、褐飞虱和家蝇的LC50分别为172．431mg/L、207．667mg／L、85．212mg／L、266．179mg／L和763．224mg／L；而且对褐飞虱、桃蚜和家蝇的活性高于苦参根提取物，苦参碱对蚜虫的活性高于氧化苦参碱和槐果碱，槐果碱对淡色库蚊、褐飞虱和家蝇的活性高于苦参碱和氧化苦参碱。     

充气压力对充气工况载重斜交轮胎影响的有限元分析

进行了充气压力对充气工况载重斜交轮胎影响的有限元分析.结果表明,充气工况下,充气压力对斜交轮胎外形轮廓尺寸影响明显,其外直径、断面宽度均随充气压力的增大而增加;充气压力的大小对胎圈接触应力分布影响很小,但胎圈最大接触应力随充气压力的增加而增大.     

安全本质的再认识与当代安全问题

从现代科学的角度揭示和分析安全的本质含义。安全本质应该包括：一是预知、预测、分析危险；二是限制、控制、消除危险。当人们讲到危险的时候，实际上是在研究危险。安全的含义随着人类社会经济的发展而变化。当代事故的灾害性、社会性、突发性是由于事故过程的技术密集性和物质高能性引起的。本文从现代科学技术和社会经济发展的基本经济规律出发，分析当代事故的本质特性。     

加压下二氧化碳在二甲基甲酰胺中的溶解度研究

本文报道了二氧化碳在二甲基甲酰胺中的溶解度,实验温度分别为15、20、25、30、35、40、45℃,实验压力为207.21—1684.02kPa.并且提出一个考虑了过量熵的、用溶度参数表示的活度系数方程.     

Seeded Crystallization of Leucite

The leucite crystallization kinetics from a hydrothermally derived precursor seeded with nano-crystalline leucite was investigated by X-ray diffraction and non-isothermal differential thermal analysis. The nano-crystalline leucite was prepared by high-energy milling of high-purity leucite powder and the leucite precursor was prepared by the hydrothermal method of silica sol, aluminum nitrate, and potassium nitrate. After the seeds were introduced, the crystallization temperature of the precursor was lowered by 100°C and the transition phase kalsilite did not appear during the crystallization process. When the seeded precursor was heat treated at 700°C, a small amount of cubic leucite was stabilized to room temperature. The seeded precursor showed an exothermic peak between 800° and 920°C under different heating rates. The activation energy for the growth of leucite from the seeded precursor was 256(SD9) kJ/mol.     

Dynamic response of Ti3SiC2 under shock compression up to 112 GPa

Ti₃SiC₂ is of interest due to its unique dual nature reminiscent of both brittle ceramics and ductile metals at ambient conditions. In this work, plate-impact experiments have been performed to study the dynamic behavior of Ti₃SiC₂ under shock compression up to 112 GPa by using laser velocity interferometer and electric pin techniques. Hugoniot elastic limits (HEL), spall strength, and Hugoniot equations of state have been obtained based on measured particle velocity profiles and shock wave velocities. The ratio of spall strength to HEL for Ti₃SiC₂ is larger than brittle ceramics but smaller than metals. This result indicates that the dual nature of Ti₃SiC₂ remains at least up to 10 GPa. On the other hand, the linearity of the Hugoniot equation of state, $D=6.9\text{0}1(22)+1.153(53)u_{\text{p}}$, suggests that the initial structure of Ti₃SiC₂ should be stable up to 112 GPa, in contrast to the result reported by Jordan et al. [J. Appl. Phys., 93 (2003) 9639].