中压汽包法兰断裂失效原因分析及改进措施

本文针对中压汽包法兰断裂失效原因进行分析，指出汽包上两个法兰同时断裂的原因在于安全阀排汽管路设计上的失误，并提出对安全阀排汽系统的改进措施。     

Two possible emission mechanisms involved in the arc discharge method of carbon nanotube preparation

By investigating the morphologies and microstructures of the cathode deposits prepared by self-sustained arc discharge between graphite rods, we consider that there are two electron emission mechanisms occurring on the cathode: field emission and thermionic emission. The former occurs mainly on the edge of the growing surface, by which we can explain the formation of the outer hard shell of the cathode deposit; while the latter occurs mainly on the growing surface except for the edge area and it is the main cause for the growth of carbon nanotubes.     

基于泄洪移民区域分汊河道泄流相互影响的模型试验研究

基于政府的组织行为、政府的协调行为和政府的监督行为与行洪移民区域后期扶持的具体工作的研究,治淮工程移民安置方案产生31.2亿元的投资。移民区域的大小与安全行洪区范围直接相关,分汊河道行洪的最佳分流比决定了行洪的安全与否。为了探讨复杂并联泄洪河道中不同的闸门控制对泄流的影响,论文结合淮河入江水道归江控制段模型试验,对复杂分汊并联河道的分流比及其流态对河道的稳定等进行了分析研究。通过对所采集的水位流量资料进行理论分析,按照不同的闸门开度组合,结合水面流态,系统分析入江水道中下段分汊并联河道在不同的流量下最优闸门开度组合及支汊分流比。单闸控制,主汊河道闸门开度一定时,分流比随着总泄流量增加而减小,两支汊河道分流比基本相同,且随总泄流量增加而增加。双闸控制,主汊河道和支汊河道闸门组合调节时,主汊分流比同单闸控制,支汊分流比变化量来自主汊,不影响其他支汊河道分流比。最优闸门开度为主汊单闸控制2/3开度,最优分流比为76%、12%、12%,在此分流比下行洪,将保持移民后期区域不扩大或缩小。     

Immobilization of biologically active species on PA‐6 foils treated by a dielectric barrier discharge

In the field of biomaterials and biomedical devices, surface activation has been focused on creating functional groups capable of preferential adsorption of biologically active species (proteins, enzymes, cells, drugs, etc.). In this way an interface can be created between the synthetic material and the biological medium, with the aim of increasing the compatibility of the implant with the human organism. In our experiments a dielectric barrier discharge (DBD), in helium at atmospheric pressure, was used as the source of energy capable of creating active centers that render the functionalized surface favorable to immobilization of biological molecules. Retention of immunoglobulin (IgG) and heparin biomolecules on polyamide‐6 (PA‐6) surfaces after treatment by the DBD was analyzed by atomic force microscopy, adhesion evaluation, and measurement of the contact angle titration in order to assess this incorporation on the treated surfaces. The marked adsorption of the biomolecules on the active sites created by DBD on the exposed surfaces also was related to a complex set of processes, such as enhanced roughness, increased surface wettability, and modified distribution of cationic and anionic groups on the treated surfaces. All these factors could promote interfacial interactions between the specific groups of the biomolecules existing in the biological medium and the type of cationic and/or anionic groups present on the surface. The efficiency of the DBD treatment showed that the DBD technique is useful for preactivation of the polymer surface for immobilization of other biologically active species (such as drugs and enzymes). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1985–1990, 2003     

水文监测创新在2016年长江洪水测报中的作用

2016年,长江中下游发生了区域性大洪水。为保证洪水预报的水文资料需求,长江委水文局通过建立的由水文监测管理体系、水文监测服务体系、水文监测技术支撑体系、水文监测质量保障体系等四大部分组成的水文监测体系创新与关键技术,以“巡测优先、驻巡结合、测报自动、应急补充”的新型水文监测模式,大大提升了防洪监测的能力和水平。与往次防洪监测比较,在应对2016年的大洪水的过程中,长江水文测验的新型模式带来了测洪能力、技术水平、准确度、时效性的系统性提升,其中,流量测验时间缩短了73%~83%,水情信息到报率和准确率达到99.95%,远远高于国家标准。     

Synthesis of carbon nanocapsules containing Fe, Ni or Co by arc discharge in aqueous solution

A simple, inexpensive and one-step synthesis method of metal-containing carbon nanocapsules using an arc discharge in aqueous solution is reported. It was found that Ni, Co and Fe nanoparticles could be in situ encapsulated in carbon shells when the arc was performed respectively in aqueous solutions of NiSO₄, CoSO₄ and FeSO₄. Transmission electron microscopy, energy dispersive X-ray spectroscopy and electron diffraction patterns of selected areas were used to determine the crystalline phase of the metal cores. To explain the formation mechanism of metal-containing carbon nanocapsules, a model of discharge in solution is proposed. This result presents a simply controllable way to synthesize metal-containing carbon nanocapsules.     

Charge transfer effects in acid treated single-wall carbon nanotubes

Single-wall carbon nanotubes (SWNTs) prepared by the arc discharge method were oxidized using nitric acid. The samples were analyzed by using Raman scattering and Fourier transformed infrared spectroscopy (FTIR). The FTIR results indicate the presence of -COOH acid groups in the treated samples. The up shifts observed in the radial breathing mode frequencies suggest that SWNTs behave as donors after the acid treatment, with charge transfer occurring from the nanotubes to the -COOH groups. Ab initio calculations of SWNTs interacting with -COOH acid groups support the charge transfer process from the nanotubes to the carboxyl groups.     

环境污染物的电化学处理技术

对电化学技术在环境污染物治理中的应用进行了综述，分析了应用中可能存在的问题，提出了相应的对策。     

水中高压脉冲放电机理与效能

水中高压脉冲放电是一种具有潜力的新型水处理技术，这是由于高压脉冲放电具有许多独特的性质。放电过程中会产生许多有利于去除污染物的复杂的物理以及化学反应。作者介绍了一些基本原理，同时综述了近来国内外高压脉冲放电水处理技术的研究发展状况，高压脉冲放电过程的催化强化去除污染物的机理以及灭菌去除污染物的效能。