电子束辐照技术对甲醇-水溶液中艾司唑仑降解研究

利用电子束辐照技术对艾司唑仑(ESL)的甲醇-水溶液进行降解,考察了溶液pH值、溶液初始浓度、不同溶剂等因素对降解效率的影响,并对降解过程进行了回归分析,探讨了艾司唑仑降解中间产物。研究表明,在初始浓度为30 mg·L~(-1)的艾司唑仑甲醇-水溶液中,当pH值为3.0,辐照剂量为6 kGy时,艾司唑仑可以完全降解。溶液pH值超过7.0,降解效率只有50%左右,要完全降解,必须增大辐照剂量。在不同溶剂中,以甲醇-水溶液中降解效率最高。ESL降解过程符合一级动力学反应,降解过程主要以破坏苯环结构为主,形成具有特征碎片离子的稳定的三环共轭体系。     

基于HL-2M 装置的等离子体可见光成像诊断系统的研制

HL-2M 托卡马克初始等离子体放电实验对等离子体可视化诊断有一定的需求,其中可见光成像系统为关键诊断之一,对初始等离子体放电有着十分重要的作用。本研究以HL-2M为平台设计研发了一套可见光成像诊断采集系统,本系统具有切向与广角两套成像诊断,可以直观准确地分析放电过程中的等离子体演化,包括等离子体击穿、维持、破裂和等离子体与壁相互作用等物理现象。系统的两套诊断通过镜头与传像光纤束进行等离子体可见光辐射的成像与传输,并以Lumenera Lt425C相机为采集和控制核心。以远程服务器控制本地并传输至数据库为控制模式,控制软件采用了VC++的多线程技术以及OpenCV软件库的图像处理技术,能够进行实时的可见光图像采集,并在放电结束后进行图像回放,同时系统具备色彩校准标定可以在装置复杂情况还原装置真实运行状态,系统具备参数配置功能,支持炮间更改参数,适应各种情况的物理实验,并有着一定的可移植性。本系统的开发研制可以满足HL-2M 装置初始等离子体放电期间的运行基本要求,在HL-2M初始等离子体放电期间取得了良好的效果,为后续推广至其他的装置提供了解决方法。     

含酚废水的超声-活性炭联合处理

含酚废水对环境具有较大危害,去除废水中的酚含量对环境安全具有重要的意义.活性炭吸附和超声降解技术都被应用于废水处理中,本文首次将这2种技术联合起来处理含酚废水,并比较了活性炭吸附、超声降解和超声-活性炭联合技术3种方浇法的效果,表明超声-活性炭联合技术对苯酚的去除率高于单独使用活性炭吸附或超声降解,探讨了溶液pH值、超声时间、活性炭投加量等因素对联合处理含酚废水效果的影响,发现处理100 ml的0.01 mol/L的模拟含酚废水,溶液pH值为5,超声处理20 mins,0.4 g活性炭振荡吸附20 mins,可使苯酚去除率达到83.9%.联合技术可以综合2种技术的优势,在废水处理中有着广阔的应用前景.     

液态电极发射光谱技术在金属离子检测中应用的研究

研究了采用液态电极等离子体光谱技术来实现金属离子检测的新方法。所建立的测试系统由如下部分组成:被测溶液构成的液态电极、固态对电极、高压发生装置和便携式光谱仪等。液态电极的优点是可以在常温常压下产生放电,并且也不需要复杂的液态样品进样系统,在现场检测等方面具有较大的应用前景。文中研究了放电的各种参数,如放电电压、放电电流、溶液pH值等对元素的光谱发射效率的影响。采用该测试系统,对Na 的检测限为0.1mg/L,而对Li ,K ,Mg2 ,Ca2 等离子的检测限为1mg/L。     

低温等离子体灭活核糖核酸酶研究

该文主要探讨了低温等离子体技术在核糖核酸酶灭活方面的应用,分析了作用气体类型和等 离子体发生器结构对酶灭活性能的影响。实验结果表明,低温等离子体能够有效地灭活核糖核酸酶, 混有氧气或水汽的作用气体能够明显提高对酶的灭活能力,且悬浮式电极介质阻挡放电装置的灭活效 果优于表面介质阻挡放电装置。     

低温等离子体制备天然功能性多糖

天然多糖由于具有天然可再生、价格低廉、生物相容好等优点,受到广泛关注。该文选择具 有代表性的羧甲基纤维素钠和海藻酸钠作为研究对象,探讨了低温等离子体技术应用于多糖改性的可 行性。通过系统地研究等离子体处理对这两种多糖溶液黏度、pH 值、菌落总数及 1,1-二苯基-2-三硝 基苯肼清除率等性能的影响,并在此基础上,分析等离子体处理对两种多糖结构和性质的影响差异及 相关机制。实验结果表明,处理后的多糖具备了一定的抗菌及抗氧化性能。主要机制为：等离子体处 理过程中产生的能量,使多糖内部的分子键断裂;这个过程中,也引入了含氧、含氮等活性官能团, 与断键之后的多糖稳定结合,从而赋予其相应的功能。相较于传统的酸、碱和酶提取法制备功能性多 糖,低温等离子体更为稳定、高效且没有任何化学试剂污染。因此,低温等离子体处理为功能性多糖 的制备提供了新的方法。     

一种工频正弦平顶波功率电源的研究

串补用火花间隙的放电特性试验需要一种工频正弦平顶波高压试验电源。为此设计了一种程控波形发生器和与之相适应的功率放大器。该装置基于单片机控制,采用D/A转换器,用以产生高精度、稳定可靠的工频正弦平顶波信号,通过放大器进行电压和功率放大。介绍了工频正弦平顶波发生器的工作原理,并通过对PA52功率放大芯片特性指标的介绍,分析了功率放大器设计方法。试验结果表明,该装置最大输出电压为80 V,频率稳定度为0.08%,电压幅值稳定度为0.5%,负载调整率为0.375%,满足火花间隙放电特性试验的要求。     

氯离子电极法测定稀土棒材中微量氯

称样2克置于200毫升烧杯中,加水少许以10毫升硝酸和少量过氧化氢溶解,转移入200毫升容量瓶中,加入26%氢氧化钠25毫升,边加边摇动,稀至刻度(pH11～12)摇匀,过滤,弃去初始滤液。吸取此滤液20毫升于50毫升容量瓶中,加1、2滴0.1%甲基     

应用等离子体实现流场主动控制技术的研究

飞行器设计的一个重要目标,就是要优化流场分布,减少阻力,增加升力,提高飞行器的升阻比,飞行器在高、亚音速巡航时,摩擦阻力超过了总阻力的一半,1%阻力的降低,将大约提高10%的有效负荷或飞行距离,传统的方法,特别是先进翼型的普遍采用,大大提高了飞行器的飞行性能,带来了巨大的经济效益和社会效益.但是,随着设计要求的进一步提高,传统的设计方法越来越显示了它的局限性.目前,国际上开始考虑通过等离子体对流场特性的影响来达到减阻这一目的.该文介绍了一个大气压下辉光放电等离子体发生装置的研制方法,并通过已成功研制的等离子体发生装置主动产生表面等离子体,揭示表面等离子体对流场以及电磁场的影响.     

均匀设计法在Pr改性SnO2/Ti电催化电极处理制药厂废水中的应用

为了提高制药厂废水处理效果,采用均匀设计方法优化自制Pr改性SnO_2/Ti电催化电极处理制药厂废水的降解条件。以COD去除率为考察指标,建立了COD去除率与电流强度、时间、Pr的掺杂量、面积比(SnO_2/Ti:Al)之间的数学模型。在回归分析的基础上,筛选出降解条件的优化参数,此时废水的COD去除率达94.9%。实验结果表明,采用均匀设计法得出最佳降解条件的配方,用Pr改性SnO_2/Ti电极和装置处理制药厂废水,处理效果良好。     

超声技术在废水处理中的应用与研究进展

超声技术作为一种新型的氧化方法,能提高难降解有机物的降解率和增强水处理中的生物活性,在废水处理中已经发挥了一定的作用并有广阔的发展前景。超声降解水中有机物主要是通过热分解、·OH自由基氧化和等离子化学和高级氧化。影响降解率的主要因素有:超声波频率、超声波声强、溶液的pH值、溶解气体的物理性质和污染物自身性质。本文介绍了超声降解有机物的机理和主要影响因素对降解水中污染物效果的影响及其机理,并综述了超声技术在废水处理中的应用与研究进展。最后指出了超声技术于废水处理中应用需解决的关键问题以及今后的发展方向。     

Electron‐beam deposition of MgO on plastic substrate and manufacturing flexible flat fluorescent lamp

Abstract— A flexible fluorescent lamp that utilizes the same plasma discharge mode as in PDPs has been manufactured. The structure of the flexible lamp is simple and easy to manufacture. All‐plastic materials including plastic substrates, barrier ribs (spacers), and sealants for low‐temperature manufacturing processing have been adopted except for the phosphor and MgO thin film. The MgO thin films were coated on the plastic substrates as a protection layer against the plasma discharge. The adhesion and biaxial texture of MgO thin film deposited on the plastic substrates, poly‐ethyle‐nenaphthalate (PEN) and polycarbonate (PC), at low temperature (100–180°C) has been characterized. The MgO film on PEN shows good adhesion under a repeated bending test. The manufactured flexible lamp consists of two plastic substrates of about 3 in. on the diagonal, barrier rib (spacer), and external ITO electrodes. The Ne‐Xe (5%) gas mixture at 100–200 Torr was used for the discharge gas. A maximum surface luminance of about 100 cd/m² was achieved for a 1 ‐kHz AC pulse.     

混凝- 膜分离集成工艺处理表面活性剂废水的研究

废水中的表面活性剂成分复杂、分子量小,若不经处理直接排入水体,将造成水体的富营养化。膜分离法处理废水存在膜易污染、清洗困难的问题。针对上述问题,文章提出采用混凝-膜分离集成工艺处理表面活性剂废水。首先,采用相转化法自制二氧化钛改性聚偏氟乙烯超滤膜,并通过扫描电子显微镜、傅里叶红外光谱、接触角测量仪测试膜的结构和性能;然后以十二烷基苯磺酸钠配制表面活性剂废水,以聚合氯化铝作为混凝剂,研究紫外光照强度、进水流量,溶液 pH值对集成工艺处理效果的影响。研究结果表明,改性膜表面具有致密分离层,断面呈指状孔和海绵状结构;傅里叶红外光谱表明聚乙二醇和二氧化钛的加入掩盖了部分聚偏氟乙烯晶型的红外吸收;二氧化钛改性膜具有更小的接触角;紫外光照强度和进水流量对混凝-膜分离工艺影响较小,溶液酸碱性对工艺影响较大,并且当溶液 pH值为4.5时集成工艺对表面活性剂废水处理效果最佳。混凝-膜分离集成工艺作为一种新型解决方案,在大规模、高效、低成本处理生活和工业废水中有望发挥重要作用。     

Space and time evolution of the plasma in a PDP cell: Comparisons between simulations and experiments

We have used a macroscopic discharge cell to study the space and time evolution of the plasma in geometry similar to real matrix and coplanar PDP cells with a scaling factor of around 100 (dimensions 100 times larger, pressure 100 times smaller, i.e., 1‐cm gap length, 5‐torr pressure). Discharges in pure neon and in a xenon‐neon mixture with 10% xenon have been investigated. The measurements have been compared with results from a two‐dimensional fluid model of the discharge.     

Mercury‐free 18‐in. flat fluorescent lamp with good uniformity

We have developed an 18‐in. 287 × 359‐mm flat fluorescent lamp (FFL) that uses a xenon dielectric barrier discharge and analyzed its electro‐optical characteristics. The surface luminance of the lamp having a diffuser sheet thickness of 3 mm was 5600 cd/m² and the luminance uniformity was 92% at an applied voltage of 950 Vrms. The luminous efficacy of the FFL was 24.5 lm/W for a luminance of 4200 cd/m² when driven by a sine‐wave voltage.     

Mercury‐free 18‐in. flat fluorescent lamp with good uniformity

Abstract— We have developed an 18‐in. 287 × 359‐mm mercury‐free flat fluorescent lamp (FFL) having a new structure that utilizes dielectric barrier discharge and contains pure xenon gas. The electro‐optical characteristics have been analyzed. The surface luminance of the lamp having a diffuser sheet is 5600 cd/m² and the luminance uniformity is 92% at an applied voltage of 1050 Vrms and an applied frequency of 20 kHz in the form of a sine wave.     

Model-free control based on reinforcement learning for a wastewater treatment problem

This article presents a proposal, based on the model-free learning control (MFLC) approach, for the control of the advanced oxidation process in wastewater plants. This is prompted by the fact that many organic pollutants in industrial wastewaters are resistant to conventional biological treatments, and the fact that advanced oxidation processes, controlled with learning controllers measuring the oxidation–reduction potential (ORP), give a cost-effective solution. The proposed automation strategy denoted MFLC-MSA is based on the integration of reinforcement learning with multiple step actions. This enables the most adequate control strategy to be learned directly from the process response to selected control inputs. Thus, the proposed methodology is satisfactory for oxidation processes of wastewater treatment plants, where the development of an adequate model for control design is usually too costly. The algorithm proposed has been tested in a lab pilot plant, where phenolic wastewater is oxidized to carboxylic acids and carbon dioxide. The obtained experimental results show that the proposed MFLC-MSA strategy can achieve good performance to guarantee on-specification discharge at maximum degradation rate using readily available measurements such as pH and ORP, inferential measurements of oxidation kinetics and peroxide consumption, respectively.     

常压等离子体射流沉积ZnO及其传感特性研究

提出了一种环保、高效、低成本的传感器制作方法.应用等离子体射流喷枪沉积ZnO半导体材料,其中等离子体射流喷枪的气源为N2,电源采用输出频率为20 kHz的高频高压电源.使用Zn(NO3)2的水溶液作为前驱物,经过雾化装置形成气溶胶,气溶胶在等离子体的氛围中成功在衬底上沉积出一层ZnO半导体材料,通过XRD、SEM、UV-Vis等对其进行表征分析.并对基于该方法制备的ZnO湿度传感器性能进行表征.ZnO沉积时间为5 min时的灵敏度最高,低湿和高湿下分别为0.435 pF/% RH和19.634 pF/% RH,同时该样品的迟滞、响应时间与恢复时间亦是最优.     

Direct observations of vacuum ultraviolet rays for surface‐discharge ac plasma displays by using an ultra‐high‐speed electronic camera

Abstract— Vacuum ultraviolet (VUV) rays emitted from Xe during the operation of surface‐discharge ac plasma‐display panels (PDPs) were observed directly by using a recently developed ultra‐high‐speed electronic camera. It is confirmed that 147‐ and 173‐nm VUV rays are emitted from both the cathode and the anode simultaneously. The direct observation shows that the emitting area for 147‐ and 173‐nm emissions above the cathode and the anode extends outward from the edge of the gap. These emission extensions are considered to be caused by a lowering of the electric field above the area due to the accumulation of wall charges. The intensity of the 147‐ and 173‐nm emissions above the anode decays faster than those above the cathode. It is clarified that the difference in the decay characteristics of VUV rays above the cathode and the anode is caused by the difference in the wall‐charge‐accumulation rates above the cathode and the anode. The major reactions concerning the generation of Xe(1s⁴), a xenon resonant state, which is related to 147‐nm emission, and that of Xe^2Y*, a xenon molecule state, which is related to 173‐nm emission, are discussed.