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污染土壤电动修复技术研究进展 总被引:3,自引:0,他引:3
《化学研究》2016,(1)
电动修复是一种新兴的原位土壤修复技术,主要用于有机及重金属污染土壤/场地的修复.本文作者介绍了电动修复污染土壤的技术原理;探讨了电动技术与Fenton技术、表面活性剂/助溶剂、超声波技术、微生物技术及渗透性反应屏障技术的联合应用;总结了土壤电动修复中,土壤pH不均衡及有机污染修复效率较低的问题.确定了电动技术与多种技术的联用为土壤修复的研究和应用趋向. 相似文献
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分析了化学课程中化工技术内容的教学价值,发现此类内容不仅是学生获取技术知识的载体,同时也是掌握技术方法、形成技术观念的载体。为更好地发挥化工技术内容的教学价值,构建了基于设计的教学模式。 相似文献
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单分子操作技术,如原子力显微镜技术、光镊技术和单分子荧光光谱技术,能够对单分子局部力进行测量,因而能在单分子水平上研究核酸的弹性性质和机械诱导的结构转变。单分子操作技术已越来越多地应用于相关的核酸研究中,如DNA的打开与修饰、DNA.蛋白质相互作用、DNA凝聚、复制和转录。与经典的分子生物学技术相比,单分子操作技术避免了从大量实验结果中取平均的需要,因而可以提供更为详细的生物信息。本文概述了单分子操作技术的原理及其在核酸研究中的应用。 相似文献
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掌上实验技术(The lab in Hand technology)与中学理科探究 总被引:2,自引:0,他引:2
掌上实验技术是由手持技术(包括数据采集器和传感器或探头)和网络技术组成的现代测量技术。它能便携式地、定量、快速、准确地测量中学理科各种科学数据,而且科学数据及其实验装置能利用多媒体计算机进行处理并能以视频和音频形式在网上传播。本文主要介绍了掌上实验技术的基本组成、主要特点以及自己的课题研究。 相似文献
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环境样品中砷、硒形态分析研究进展 总被引:2,自引:0,他引:2
综述了近年来环境样品中砷、硒形态分析的研究进展,主要内容包括样品的前处理技术、分离技术、检测技术。前处理技术主要是用各种提取液采用各种方式提取样品中的砷、硒形态,分离技术主要有高效液相色谱分离、气相色谱分离、毛细管电泳分离等,检测技术主要有原子吸收光谱法、原子发射光谱法、原子荧光光谱法、电感耦合等离子体质谱法等。最后对其研究前景进行了展望。 相似文献
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本文详细及正确地介绍了放射性元素钷的发现史,特别强调了离子交换技术在钷的分离及鉴定中的重要作用。 相似文献
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DNA分子识别及传感技术 总被引:3,自引:0,他引:3
DNA杂交生物传感器为基因的识别及疾病的诊断提供了一种快速,简便,廉价的方法,此文从DNA的固定及检测技术两个方面,举例介绍了各不同方式的研究应用现状及对传感器灵敏度,杂交专一性,杂交速度及使用寿命的影响,对DNA识别技术的发展前景进行了展望。 相似文献
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辛仁轩 《中国无机分析化学》2013,3(1):1-10
微波等离子体光源是一类重要的有较强激发能力的原子发射光谱光源,主要包括微波感生等离子体光源,电容耦合微波等离子体光源及微波等离子体炬光源。本文是微波等离子体光谱技术发展的第二部分,主要介绍了电容耦合微波等离子体光源及微波等离子体炬光源的结构原理和性能。并对它们的技术特点和进展进行评述。 相似文献
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Contribution of UV light to the decomposition of toluene in dielectric barrier discharge plasma/photocatalysis system 总被引:1,自引:0,他引:1
Hai Bao Huang Dai Qi Ye Ming Li Fu Fa Da Feng 《Plasma Chemistry and Plasma Processing》2007,27(5):577-588
The contribution of UV light from plasma and an external UV lamp to the decomposition of toluene in a dielectric barrier discharge
(DBD) plasma/UV system, as well as in a plasma/photocatalysis system was investigated. It was found that UV light from the
DBD reactor was very weak. Its contribution to the removal of toluene in the plasma/photocatalysis system could be ignored.
Whereas, the introduction of external UV light to the plasma significantly improves the removal efficiency of toluene by 20%.
The removal efficiency of toluene in the plasma/photocatalysis system increased about 22% and 16% when compared with a plasma
only system and plasma driven photocatalyst system, respectively. The increased toluene removal efficiency was mostly attributed
to the contribution of the synergy between plasma and UV light, but not to the synergy between plasma and photocatalysis.
The synergetic effect between plasma and photocatalysis was not significant. 相似文献
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Methods permitting to test the influence of the matrix as well as of its local and temporal distribution on the plasma conditions in laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS) are developed. For this purpose, the MS interface is used as plasma probe allowing to investigate the average plasma condition within the ICP zone observed in terms of temporal and spatial distribution of the matrix. 相似文献
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N. Inagaki S. Tasaka Y. Yamada 《Journal of polymer science. Part A, Polymer chemistry》1992,30(9):2003-2010
Plasma polymerizations of three cyano compounds—acrylonitrile (AN), 1,2-dicyanoethylene (FN), and tetracyanoethylene (TCE)—were investigated by FT IR and XPS, and the transforamtion of cyano groups during the plasma polymerization was discussed. The results pointed out an aspect of the preparation of plasma films with cyano groups. Plasma polymerizations of AN, FN, and TCE deposited brown or dark brown films that contained carbon, nitrogen, and oxygen. The elemental composition of the plasma films, especially N/C atomic ratio, showed a monomer dependence but no rf power dependence. The plasma films contained amide and amino groups, and ketene-imine and conjugated — C = N — structures as well as cyano groups as nitrogen functionalities, and carbonyl and carboxyl groups as oxygen functionalities. For the preparation of plasma films with cyano groups, compounds with more than two cyano groups themselves are not suitable as monomers. The operation of plasma polymerization under mild plasma conditions at low rf power and in no oxygen atmosphere is favorable for the preparation of plasma films with cyano groups. © 1992 John Wiley & Sons, Inc. 相似文献
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Chen Q 《The journal of physical chemistry. B》2006,110(18):9231-9235
Recently, surface plasmon resonance (SPR) has been successfully implemented to characterize the film stability in real time: a radio frequency (RF) plasma polymerized film was monitored by swelling or extracting behaviors in aqueous solution. The high-resolution SPR revealed that film stability strongly depended on the monomers, plasma mode, and substrate locations as well as plasma polymerization conditions: incident power and working pressure. By Fourier transform infrared (FTIR), the possible reasons of film stabilization affected by plasma conditions and sample locations are explained. It is recommended that as an adhesive layer for future applications the plasma polymerized polymer shall be prepared in low working pressure pulsed plasma. 相似文献
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《Journal of membrane science》2001,188(1):97-114
A plasma treatment that renders asymmetric polysulfone membranes permanently hydrophilic is reported. Our modification strategy entails treating these membranes downstream from an inductively coupled rf plasma source. Contact angle measurements confirm that the membranes are completely wettable with water as a result of H2O plasma treatment. More importantly, the hydrophilic modification is permanent as plasma-treated membranes remain wettable for more than 16 months after plasma treatment. This treatment achieves the desired change in wettability for microporous as well as ultrafiltration polysulfone membranes, illustrating the universality of this method. XPS analysis of treated membranes demonstrates this dramatic change in wettability is a result of chemical changes in the membrane induced by plasma treatment. Moreover, the membrane modification is complete as the plasma penetrates the thickness of the membrane, thereby modifying the entire membrane cross-section. 相似文献
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《Spectrochimica Acta Part B: Atomic Spectroscopy》2004,59(4):401-418
A radiation dynamic model is developed for a post-breakdown stage of a laser induced plasma expanding into vacuum. The model describes the plasma formed on a small solid particle, which is completely vaporized by a laser. The symmetry of the expanding plasma is spherical. The time frame for the applicability of the model is somewhat between a hundreds of nanoseconds, after the laser pulse is terminated, and a few microseconds, when the plasma ceases to emit. The model is based on a system of gas dynamic equations coupled with the equation of radiative transfer. Local thermodynamic equilibrium is assumed, allowing the application of the collision-dominated plasma model as well as standard statistical distributions. Calculations are performed for a dual SiC system, although calculations for any arbitrary number of system's components are permitted. The model has two implications. First, an analytical expression for the plasma radiation dynamics is obtained by artificially setting the initial conditions. Second, from experimentally measured plasma parameters, information is deduced about the initial state of the plasma. The main model input parameters are the total number and distribution of plasma species and the initial distribution of temperature. Some of the other model inputs, such as the speed of the plasma front and the temperature profile across the plasma can be directly measured, thus providing valuable experimental feedback to the model. The model outputs are the evolution of plasma temperature, the spatial and temporal distributions of atoms, ions and electron number densities and the evolution of the plasma spectrum in a desirable spectral window (e.g. 280–290 nm for the chosen in this work SiC system). 相似文献
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A plasma reactor based on a plasma generator with meltable electrodes is described. The specific features of the plasma generator, which are the absence of electrode erosion and the possibility of using steam as a plasma gas, extend the range of potential practical application of thermal plasma. The results of study of the arc properties are presented, and examples of industrial implementation of processes run in the plasma reactor based on the meltable-electrode plasma torch are given. 相似文献
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Bacterial infections of medical devices present severe problems connected with long-term antibiotic treatment, implant failure, and high hospital costs. Therefore, there are enormous demands for innovative techniques which would improve the surface properties of implantable materials. Plasma technologies present one of the compelling ways to improve metal’s antibacterial activity; plasma treatment can significantly alter metal surfaces’ physicochemical properties, such as surface chemistry, roughness, wettability, surface charge, and crystallinity, which all play an important role in the biological response of medical materials. Herein, the most common plasma treatment techniques like plasma spraying, plasma immersion ion implantation, plasma vapor deposition, and plasma electrolytic oxidation as well as novel approaches based on gaseous plasma treatment of surfaces are gathered and presented. The latest results of different surface modification approaches and their influence on metals’ antibacterial surface properties are presented and critically discussed. The mechanisms involved in bactericidal effects of plasma-treated surfaces are discussed and novel results of surface modification of metal materials by highly reactive oxygen plasma are presented. 相似文献
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The surface wave produced plasma belongs to a class of RF and microwave induced plasmas. It results from the propagation of an electromagnetic wave which uses the plasma column it sustains and the plasma tube as its sole propagating media. This type of plasma offers several advantages compared to the positive column plasma of dc discharges or to other RF and microwave produced plasmas. Surface wave plasmas require no internal electrodes, and they can be applied over an extremely broad range of wave frequencies (27 MHz to 10 GHz demonstrated) and gas pressures (about 10–4 Torr to a few times the atmospheric pressures). Using the surface wave plasma technique, a large variety of plasma column diameters have been created (0.5–150 mm demonstrated) and no limitation on plasma column length (column up to 6 m long demonstrated) has been found. The surface wave produced plasma is used in elemental analysis and to sustain emission in lasing media. This article is intended as a guide for potential users of surface wave plasmas in the field of plasma processing and plasma chemistry. 相似文献