Treatment of simulated wastewater containing Reactive Red 195 by zero-valent iron/activated carbon combined with microwave discharge electrodeless lamp/sodium hypochlorite

A comparative study of treatment of simulated wastewater containing Reactive Red 195 using zero-valent iron/activated carbon （ZVI/AC）, microwave discharge electrodeless lamp/sodium hypochlorite （MDEL/NaCIO） and the combination of ZVI/AC- MDEL/NaCIO was conducted. The preliminary results showed the two steps method of ZVI/AC-MDEL/NaCIO had much higher degradation efficiency than both single steps. The final color removal percentage was nearly up to 100% and the chemical oxygen demand reduction percentage was up to approximately 82%. The effects of operational parameters, including initial pH value of simulated wastewater, ZVI/AC ratio and particle size of ZVI were also investigated. In addition, from the discussion of synergistic effect between ZVI/AC and MEDL/NaCIO, we found that in the ZVI/AC-MEDL/NaCIO process, ZVI/AC could break the azo bond firstly and then MEDLfNaCIO degraded the aromatic amine products effectively. Reversing the order would reduce the degradation efficiency.

Photolysis of H_2S with interior microwave discharge electrodeless lamps

The luminescent properties of microwave discharge electrodeless mercury lamp（MDEL-Hg） which was ignited within the resonant cavity and photolysis of hydrogen sulfide with low concentration were studied in this paper.Experiment results indicated that the Interior MDEL-Hg could be made the best of energy utihzation and the efficiency of photolysis of H2S was very significant under the experimental conditions with the initial H2S concentration of 7.9 mg m^-1.With residence time of 1.5 s,the removal efficiency of hydrogen sulfide was 91%,the absolute removal amount（ARA） was 3.24μg s^-1 and the energy consumption was 58.23 mg（kWh）^-1.

The near-infrared spectra and distribution of excited states of electrodeless discharge rubidium vapour lamps

The population ratio between the excited states of rubidium in the electrodeless discharge rubidium vapour lamp is calculated according to the near-infrared spectra in the region of 780-1550 nm. By using a 1529 nm laser, we measure the density of natural rubidium atoms at the 5P3/2 level. The populations of different excited states are then clarified.

Electrical and Optical Characteristics of Electrodeless Lamp

In order to study the methods to enhance the efficacy of electrodeless lamp,volt-ampere characteristics,illuminance and emission spectrum have been investigated in home-built electrodeless lamp experimental system with an electrodeless lamp in shape like QL 85 lamp.The results show that lamp current increases as lamp voltage increases in non-discharge,the current decreases first and then increases as the voltage increases in discharge.The illuminance of electrodeless lamp increases linearly with discharge power increasing,and it decreases linearly with power decreasing.The emission spectrum is different for different bulb and lighting time.The spectrum of Ar 811.5 nm,76.5 nm,750.4 nm and Hg 313.2 nm decrease with lighting time.While the intensity of Hg 407.8 nm increases with lighting time.

Modelling of Ar-Hg Electrodeless Lamps

A self-consistent model of high-frequency electrodeless lamps with internM coils is developed. Radial distributions of the plasma parameters are obtained. Mercury lines with wavelength of 435.8 nm and 365 nm are measured to testify the model. Based on the model, the population of resonance state 63p1 of mercury in dependence on the argon pressure and driving frequency is calculated. It is shown that the population of 63p1 of mercury is larger when the argon pressure is between 26.6 Pa and 53.2 Pa. Meanwhile the driving frequency has little influence on the population of 63P1.

Low pressure mercury–argon electrodeless fluorescent lamp simulation using the finite volume method

A finite volume model of a low pressure Ar-Hg electrodeless lamp with external coils is established. The physical configuration is similar to the OSRAM/ENDURA 70 W lamp. A Maxwellian energy distribution is assumed. Two dimensional behaviors of the most important plasma parameters such as the electron density, the electron temperature and the most important mercury states are discussed. Results are in good agreement with former studies and the general understanding in this area. Also, the influence of the argon pressure is studied. Based on the simulation, the population of the main resonance state, Hg （63p1） depends on the argon pressure and the optimized value is about 300 mTorr.

Population Distribution of Excited States in Cs Electrodeless Discharge Lamp

We measure the intensity of fluorescence spectral lines of Cs atoms in an electrodeless discharge lamp from visible light to the near-infrared region of 400-100Ohm. To build an excited state Faraday anomalous dispersion optical filter, the population ratios between the excited states are calculated by rate equations and the spontaneous transition probabilities. The electrodeless discharge lamp with populations in the excited states can be used to realize the frequency stabilization reference for lasers at multiwavelength and the excited state Faraday anomalous dispersion optical filter for submarine communication applications in blue-green wavelengths to simplify the system.

The roles of active species in photo-decomposition of organic compounds by microwave powered electrodeless discharge lamps

Knowledge of the effective radiation spectrum irradiating substrates from microwave powered electrodeless discharge lamps（MEDLs）, and the active species that directly oxidize substrates in the photolytic process, is fragmentary and unclear. In this work, we conducted a comparative study using MEDLs made with quartz envelopes（MEDL-quartz） and with borosilicate Pyrex envelopes（MEDL-Pyrex） targeting the degradation of Rhodamine B（Rh B）via radical-extinguishing tests. We found that UVC/UVB radiation is essential to generate·OH and H2O2 in the MEDL-quartz system. The degradation of Rh B mostly originates from·OH species, which account for a contribution of 53.8%, while the remaining contribution is attributed to oxidation by H2O2 and direct photolysis. This degradation is influenced by several parameters. Acidic and neutral p Hs, but not extreme alkaline p H, benefit the degradation. To ensure a high intensity of UVC/UVB, the optimum ratio of the MEDL volume to the aqueous solution volume（VL/VS） is 0.4. Concentrations of 0.15-0.20 mmol/L of Rh B are suitable to obtain an effective quantum absorbance in the MEDL-quartz system,showing a high decomposition rate of 5.6 × 10^-3（mmol/L）min-1. Moreover, two other substrates, Reactive Brilliant Red X-3B and Safranine T, were tested and found to be efficiently degraded in the MEDL-quartz system.

Atomic population distribution of excited states in He electrodeless discharge lamp

Population ratios between excited states are measured to build the excited state Faraday anomalous dispersion optical filter(ESFADOF). We calculate these values between the excited states according to the spontaneous transition probabilities using rate equations and the measured intensities of fluorescence spectral lines of He atoms in an electrodeless discharge lamp in the visible spectral region from 350 to 730 nm. The electrodeless discharge lamp with populations in excited states can be used to realize the frequency stabilization reference of the laser frequency standard. This lamp can also build ESFADOFs for submarine communication application in the blue-green wavelength to simplify the system without the use of a pump laser.

Distribution of populations in excited states of electrodeless discharge lamp of Rb atoms

The intensity of fluorescence spectral lines of Rb atoms in the region of 350-1110nm is measured in eletrodeless discharge lamp. The population ratio between the excited states is calculated according to the spontaneous transition probabilities with rate equations. At the same time, the population density of energy level is also obtained. The results provide the potential applications of electrodeless discharge lamp in atomic filter and optical frequency reference at higher excited states without a pumping laser.

无电极洛伦兹力推力器的电路模型

无电极洛伦兹力推力器(ELF)具有比冲高、无电极腐蚀、推力大、可选工质多等优点,可考虑与其他推力器共同组合成复合推力器,可作为新型大功率推力器的发展方向。本文针对该推力器提出了一种电路模型,其中旋转磁场线圈被等效为相位相差90°的集总参数电感,将等离子体等效为具有电容性和电阻性元件的电感负载。基于基尔霍夫定律和电流连续性方程,推导出了推力器的推力产生公式。结果表明,对于高输入能量,效率与输入能量成反比,比冲和效率都随着耦合的增加而提高,并且随着输入能量的增加,存在一个最佳效率。

场反构型无电极洛伦兹力推力器研究进展

场反构型洛伦兹力推力器利用旋转磁场驱动等离子体产生场反构型等离子体团(Filed Reversed Configuration-FRC),并利用洛伦兹力将其加速产生推力。由于该推力器不使用栅极加速,故不存在栅极溅射问题,大大延长推力器工作寿命。该技术借鉴自磁约束核聚变技术,推力密度大、功率扩展性好(MW级),在未来的深空探测和星际航行中具有广泛的应用前景。文章对场反构型洛伦兹力推力器发展现状进行了综述,并对工作原理、计算模型和技术瓶颈问题作了介绍,为中国等离子体推力器技术发展提供参考。

水溶液中4-氯酚的微波辅助光化学降解

研究了微波辅助无极紫外灯 (MW /UV)光化学降解 4 氯酚 (4CP)模拟废水 ;为了考察溶液中 4CP的降解效果 ,用紫外可见分光光度法 (UV VIS)和离子色谱法 (IC)测定了溶液中 4CP的降解率和Cl-浓度 .结果表明 ,MW /UV体系中 30mg/L 4CP反应 1 2 0min的降解率由紫外 (UV)光解体系的 2 1 5 6 %提高到 5 2 4 0 % .提高溶液的pH值、向体系通入氧气、增强光照度以及外加氧化剂H2 O2 均能增加水溶液中 4CP的降解率 .微波辅助光化学降解

微波辅助光催化降解4-氯酚的研究

采用了一种新的水处理技术微波辅助光催化(MW/UV/P25)降解4-氯酚(4CP)模拟废水。初始质量浓度为30mg/L的4CP在微波光催化下发生了降解,反应120min,4CP的降解率达到82.85%,Cl-质量浓度增加值为7.95mg/L。4CP的降解率与溶液的pH、通气条件、紫外灯光照度等因素有关,外加H2O2氧化剂能够加速4CP的降解。微波辅助光催化降解4CP服从一级反应动力学方程。

无极灯启动特性研究

为了研究提高无极灯光效的方法,本文测量了无极灯启动阶段的电参数和发射光谱,分析了点灯后阻抗、Hg原子光谱强度、Ar原子光谱强度、等离子体参数和放电模式随时间的变化规律。结果表明,在启动阶段,无极灯阻抗发生了升-降-升的变化;Hg原子谱线强度在某稳定位置附近做相对稳定的波动;Ar原子光谱强度迅速下降到某稳定值;电子浓度迅速下降到某稳定值,中能电子温度相对稳定;放电处于H型放电模式。这为进一步设计电子整流器和提高无极灯的光效奠定了基础。

印染废水的深度处理及回用

印染废水经“无极紫外光催化氧化+微波等离子体强化活性炭吸附”工艺深度处理后,水质达到了车间用水要求,回用水与自来水的水质特性无明显差异,使用回用水和新鲜水染色,两者在特性和质量上没有明显的差异。

电阻率法研究矿物掺合料对水泥早期水化的影响

进一步开发利用矿物掺合料潜在的水化活性一直受到关注。有文献表明:水泥浆体的早期水化与其电阻率有着一定的关系,但用电阻率法对水泥浆体早期水化研究较少。基于此,本文研究了掺矿物掺合料浆体的水化过程,并采用一种新型仪器———非接触式电阻率测量仪。试验还通过强度测试和XRD作了定量和定性的分析。结果表明:电阻率曲线不仅表现了掺不同矿物掺合料的浆体的水化过程,也表现了不同矿物掺合料的活性的大小。强度试验和XRD对矿物掺合料的活性作了进一步的证实。

新型微波无极紫外光源用于光化学反应的综合评述

用于光化学反应的光源中,微波无极紫外光源可以完全避免普通紫外光源的一系列问题。由于该类光源没有电极,不会产生像其他放电光源那样由于电极氧化、损耗和封接密封问题引起的发黑现象,而且很少受工作电压、工作频率、工作电流的限制。研究结果表明微波无极紫外光源具有发光强度高,启动快,形状可灵活多变等特性。将微波无极紫外灯取代普通紫外灯,应用于环境治理,能提高处理效果,降低投资和运行成本。

微波紫外无极碘灯降解硫化氢气体

采用微波激发方式使无极碘灯发生放电,产生207 nm紫外辐射,并用于降解H2S气体.考察了初始ρ(H2S)、停留时间和微波电源功率等因素对H2S降解的影响.结果表明:H2S在微波无极碘灯停留时间为1.75 s时,其降解率随初始ρ(H2S)的升高而降低.初始ρ(H2S)为57.5 mg/m3时,H2S降解率为20.5%;初始ρ(H2S)为7.3 mg/m3时,H2S降解率可达到64.2%.在保持初始ρ(H2S)及停留时间不变的情况下,H2S降解率随电源功率的增加而提高.H2S经微波碘灯光解后的最终产物含有SO42-.

新型无极LCD平板背光源

为了降低制作成本,提高生产效率,实现液晶显示器在大尺寸品种上的高画质化,文章介绍研制的一种新型等离子体激发发光平板背光源。该电光源无电极,在两片平板玻璃中间充入纯氙气(气压2.67×104Pa),玻璃的外表面上密封一层透明水膜作为导电介质,以1.1mm厚的玻璃板作为介质阻挡层,在高频交变电压的作用下,产生等离子体,激发荧光粉发光。发光亮度可达3000cd/m2,最佳激发频率10.2kHz,启动电压6kV,发光均匀度大于92%;并综合评价了驱动电压、激发频率和样品厚度等因素对背光源发光特性的影响。