溶气吹脱法处理钽铌生产氨氮废水

用溶气吹脱法对某公司钽铌生产废水进行处理,分析了pH值、温度、时间和通气量等因素对氨氮去除率的影响。在实验条件为pH=9、温度为50℃、时间为45min、通气量为2.5L/min时,氨氮的去除率达到90%以上。

浮选柱的气溶发泡法

本文描述的这项实验工作是要寻找一种在一个浮选柱中,以适当的方式产生细小气泡,实现较高的充气率的方法。细小气泡对于达到较高的浮选效率十分重要。使用超声波气溶发泡器将气流直接加入有起泡剂的矿液中,采用多孔玻璃和滤布做起泡扩散装置。气溶发泡法产生的气泡直径是传统发泡法的1/3～1/2,起泡剂用量也较低。

超微气泡对铜酞青污水处理的实验研究

气浮法广泛应用于污水处理、气浮选矿、生化反应等领域。气浮法中微气泡的应用相当广泛,但对微气泡生成的机理研究一直是值得探讨的前沿课题。通过微气泡发生装置对微气泡的效果进行实验研究。依据微气泡运动过程中的表面吸附以及传质特性,通过实验观测微气泡对含有氨、邻苯二甲酸及铜酞青类污染物水样的去除效果和主要影响因素,了解微气泡在污水中的处理效果,从而对实际应用起到借鉴作用。

射流加压溶气气浮法的应用

一、概述 水是一种非常宝贵的自然资源,也是自然界一切生命赖以生存、人类赖以生活、生产和发展的物质之一,是一种不可代替的重要资源。随着工农业生产的不断发展,工业废水严重污染水源,使水的供需矛盾越来越突出,节约用水,保护水资源已是刻不容缓。众所周知,造纸工业是一个用量大。

Advances in Supercritical Fluid Crystallization

The supercritical fluid crystallization technique is a novel technology for preparing ultrafine particles. This paper introduced the concept and features of the technique with an emphasis on three kinds of supercritical fluid crystallization techniques, i.e. rapid expansion of supercritical solutions, supercritical fluid anti-solvent and particles from gas saturated solutions Some questions and the prospect of this technique were also discussed.

Gas sensing properties of SnO_2 nanoparticles mixed with gold nanoparticles

SnO2nanoparticles mixed with different amounts of gold nanoparticles(GNPs)were synthesized and their CO sensingproperties were investigated.The sol-gel method was employed to prepare the initial solution.SEM,TEM,XRD,DLS andspectrophotometry were used to characterize the nanoparticles.The pure sensors showed a response of about4to12.8for(20-80)×10-6CO at operating temperature of340°C.The response and recovery time at50×10-6Co is about10and14s,respectively.The amount of GNPs optimized was used to create high performance GNP-SnO2sensors(m(Au)/m(Sn)=3.7663×10-4)and optimal operating temperature was about260°C and the response at concentrations of(20-80)×10-6was8.3to29.5,respectively.

浅议喷射技术在菌体蛋白提取中的优点

味精废水含有丰富的营养物质,通过喷射加热,溶气射流絮凝的方法,达到味精废水的综合利用。

Photocatalytic H_2 evolution activity of CuO/ZrO_2 composite catalyst under simulated sunlight irradiation

Zirconia-supported CuO （CuO/ZrO2） composite photocatalysts were successfully synthesized via citric acid-assisted sol-gel technique. For comparison, CuO/ZrO2 materials were also prepared by solid state reaction and co-precipitation method. The as-prepared powders were characterized by X-ray diffractometry （XRD）, transmission electron microscopy （TEM）, and thermogravimetric-differential thermal analysis （TG-DTA）. The photocatalytic activity of CuO/ZrO2 catalyst was investigated based on the H2 evolution from oxalic acid solution under simulated sunlight irradiation. The effects of molar ratio of CuO to ZrO2, preparation method, phase change with the calcination temperature and the durability on the photocatalytic activity of the photocatalyst were investigated in detail. It is found that the optimal activity of photocatalytic H2 evolution （2.41 mmol.h i.g-~） can be obtained when CuO/ZrO2 composite photocatalyst is synthesized by sol-gel technique and the mole ratio of CuO to ZrO2 is 40%. The activity of copper oxide supported on monoclinic ZrO2 calcined at higher temperature is much higher than that on tetragonal ZrO2 calcined at lower temperature, and the best calcination temperature is 900 ℃.

Determination of Water Content of Water-soluble Paints by Gas Chromatography

This paper describes the determination of water content of water-soluble paints by gas chromatography. The water in paints is extracted by dimethyl formamide (DMF) as a solvent.Isopropanol is used as an internal standard. The mixture is separated by low-speed centrifugation.Then a 1-uL sample of the supernatant from the prepared solution is injected into the gas chromatograph. The water content is determined by internal standard calibration curve. The rate of recovery of added standard of this method is more than 98%. Relative mean deviation is less than 3‰.The linearity of calibration curve is good and relativity coefficient is higher than 0.998.

Measurement of Infinite Diluted Activity Coefficient of Solvents in Polymer by Inverse Gas Chromatography Method

The infinite diluted activity coefficients of solvents in polyisopropyl methylacrylate was measured using inverse gas chromatography. The solvents used were benzene, toluene, ethyl benzene, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methanol, ethanol isopropyl alcohol, butyl alcohol, 1,2-dichloroethane, and chloroform. It was observed that the infinite diluted activity coefficient of alcohols are well above those of the other solvents investigated.

Simulating Deposition of Aerosol Particles on Single Fiber Surface

The stochastic simulation method, based on the concept of control window and the numerical solution of the Langevin equation, is applied to solve the deposition problem of particles from the flowing suspensions onto a fiber collector. Using the Kuwabara model to characterize the flow field, the effects of Stokes number, interception parameter, packing density, particle size distribution on the collection efficioncy, and the deposition morphology of particles onto a collector are i examined. The morphology of deposit obtained in the simulated results agrees Well with experimental observations. The estimation of the initial coUection efficiency through the simulations considers that the deposited particles are in good agreement with published experimental data. In addition, the collection efficiency of particles increases in a wider particle size distribution region.

Study of Dissolved Chlorofluorocarbons in Lake Washington

Measurements of three chlorofluorocarbons (CFCs): trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12) and trichlorotrifluoroethane (CFC-113), along with methyl chloroform (CH 3CCl 3) and carbon tetrachloride (CCl 4) were made in water samples from Lake Washington, using Electron Capture-Gas Chromatography (EC-GC). The samples were collected in mid-autumn, a period when the lake’s upper layer undergoes rapid cooling. At the time of sampling, a strong vertical temperature gradient was present in the lake, with surface temperatures of ～14℃, and near bottom (50 meters) temperatures of ～8℃. The concentrations of dissolved CFC-12 and CFC-11 increased with depth, as expected from the higher solubilities of these gases at lower temperatures. Atmospheric measurements made at the sampling site at the time of the cruise, showed that CFC-11 and CFC-12 saturations in the near surface samples were 100 % and 106%, respectively. For the deepest sample (52 meters) CFC-11 and CFC-12 saturations were 102 % and 126 %. Because the surface layer of the lake responds to changes in atmospheric CFCs on a time scale of several weeks, the higher than equilibrium concentrations of CFC-12 observed at the time of sampling may reflect earlier episodes of elevated levels of atmospheric CFC-12 in this urban area. High concentrations of dissolved CFCs in runoff or industrial effluent might also lead to elevated CFC levels in the lake. The cold, deep water of Lake Washington is relatively isolated from the effects of surface gas exchange except during winter, and the supersaturations observed in the deep layer may reflect periods of elevated atmospheric CFC-12 levels from the previous winter season. These results were compared to summertime profiles of CFC-11 and CFC-12 made in 1994.

Preparation and Application of the Sol–Gel Combustion Synthesis-Made CaO/CaZrO_3 Sorbent for Cyclic CO_2 Capture Through the Severe Calcination Condition

Calcium looping method has been considered as one of the efficient options to capture C02 in the combustion Ilue gas. CaO-based sorbent is the basis for application of calcium looping and should be subjected to the severe calcination condition so as to obtain the concentrated C02 stream. In this research, CaO/CaZrO3 sorbents were synthesized using the sol-gel combustion synthesis （SGCS） method with urea as fuel. The cyclic reaction performance of the synthesized sorbents was evaluated on a lab-scaled reactor system through calcination at 950 ℃ in a pure C02 atmosphere and carbonation at 650 ℃ in the 15% （by volume） C02. The mass ratio of CaO to CaZr03 as 8：2 （designated as CasZr2） was screened as the best option among all the synthesized CaO sorbents for its high CO2 capture capacity and carbonation conversion at the initial cycle. And then a gradual decay in the C02 capture capacity was observed at the following 10 successive cycles, but hereafter stabilized throughout the later cycles. Furthermore, structural evolution of the carbonated CasZr2 over the looping cycles was investigated. With increasing looping cycles, the pore peak and mean grain size of the carbonated CasZr2 sorbent shifted to the bigger direction but both the surface area （SA） ratio and surface fractal dimension Ds decreased. Finally, morphological transformation of the carbonated CasZr2 was observed. Agglomeration and edge rounding of the newly formed CaC03 grains were found as aggravated at the cyclic carbonation stage. As a result, carbonation of CasZr2 with C02 was observed only confined to the external active CaO by the fast formation of the CaC03 shell outside, which occluded the further carbonation of the unreacted CaO inside. Therefore, enough attention should be paid to the carbonation stage and more effective activation measures should be explored to ensure the unreacted active CaO fully carbonatPd river the extended Ioonin cycles.

Separation of arenols from a high-temperature coal tar

A high-temperature coal tar collected from Xuzhou Coking Plant, Saint-Gobain Pipelines （Xuzhou） Co., Ltd. was exhaustively extracted with petroleum ether （PE）. The extract was sequentially eluted through silica gel with PE and PE/ethyl acetate （EA） mixed solvents （volume ratio 2：1 ） to afford two eluted frac- tions. The extract and eluted fractions were analyzed with gas chromatography/mass spectrometry. In total, 14 arenols were detected, including phenol, cresols, xylenols, fluorenols, phenanthren-3-ol and pyren-l-ol.

Aerosol Type Identification Using PARASOL Multichannel Polarized Data

PARASOL(Polarization & Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) multi-channel and multi-directional polarized data for different aerosol types were compared.The PARASOL polarized radiance data at 490 nm,670 nm,and 865 nm increased with aerosol optical thickness(AOT) for fine-mode aerosols;however,the polarized radiances at 490 nm and 670 nm decreased as AOT increased for coarse dust aerosols.Thus,the variation of the polarized radiance with AOT can be used to identify fine or coarse particle-dominated aerosols.Polarized radiances at three wavelengths for fine-and coarse-mode aerosols were analyzed and fitted by linear regression.The slope of the line for 670 nm and 490 nm wavelength pairs is less than 0.35 for dust aerosols.However,the value for fine-mode aerosols is greater than 0.60.The Support Vector Machine method(SVM) based on 12 vector features was used to discriminate clear sky,coarse dust aerosols,fine-mode aerosols,and cloud.Two cases were given and validated by AErosol RObotic NETwork(AERONET) measurements,MODIS(Moderate Resolution Imaging Spectroradiometer) FMF(Fine Mode Fraction at 550 nm) images,PARASOL RGB(Red Green Blue) images,and CALIOP(Cloud-Aerosol Lidar with Orthogonal Polarization) VFM(Vertical Feature Mask) data.

Measurement of aerosol effective density by single particle mass spectrometry

Single particle mass spectrometry has been widely used to determine the size and chemical compositions of at- mospheric aerosols; however, it is still rarely used for the microphysical properties measurement. In this study, two methods were developed for determining aerosol effective density by a single particle aerosol mass spectrometer （SPAMS）. Method I retrieved effective density through comparison between measured light scattering intensities and Mie theoretical modelled par- tial scattering cross section. Method Ⅱ coupled a differential mobility analyzer （DMA） with SPAMS to simultaneously deter- mine the electric mobility and vacuum aerodynamic diameter, and thus the effective density. Polystyrene latex spheres, ammo- nium sulfate and sodium nitrate were tested by these methods to help validate their effectiveness for determining the aerosol effective density. This study effectively extends SPAMS measurements to include particle size, chemical composition, light scattering, and effective density, and thus helps us better understand the environment and climate effects of aerosols.

Advanced partial nucleation for single-phase FA0.92MA0.08PbI3-based high-efficiency perovskite solar cells

To date, extensive research has been carried out,with considerable success, on the development of highperformance perovskite solar cells(PSCs). Owing to its wide absorption range and remarkable thermal stability, the mixedcation perovskite FAxMA1-xPbI3(formamidinium/methylammonium lead iodide) promises high performance. However, the ratio of the mixed cations in the perovskite film has proved difficult to control with precursor solution. In addition, the FAxMA1-xPbI3 films contain a high percentage of MA+and suffer from serious phase separation and high trap states, resulting in inferior photovoltaic performance. In this study, to suppress phase separation, a post-processing method was developed to partially nucleate before annealing, by treating the as-prepared intermediate phase FAI-Pb I2-DMSO(DMSO: dimethylsulfoxide) with mixed FAI/MAI solution. It was found that in the final perovskite, FA0.92MA0.08 PbI3, defects were substantially reduced because the analogous molecular structure initiated ion exchange in the post-processed thin perovskite films, which advanced partial nucleation. As a result, the increased light harvesting and reduced trap states contributed to the enhancement of open-circuit voltage and short-circuit current. The PSCs produced by the post-processing method presented reliable reproducibility, with a maximum power conversion efficiency of 20.80% and a degradation of ~30% for 80 days in standard atmospheric conditions.

XCO_2 satellite retrieval experiments in short-wave infrared spectrum and ground-based validation

Based on the optimal estimation method, a satellite XCO2 retrieval algorithm was constructed by combining LBLRTM with VLIDORT. One-year GOSAT/TANSO observations over four TCCON stations were tested by our algorithm, and retrieval results were compared with GOSAT L2 B products and ground-based FTS measurements. Meanwhile, the influence of CO2 line mixing effect on retrieval was estimated, and the research showed that neglecting CO2 line mixing effect could result in approximately 0.25% XCO2 underestimation. The accuracy of XCO2 retrievals was similar to GOSAT L2 B products at cloud-free footprints with aerosol optical depth less than 0.3, and 1% accuracy of XCO2 retrievals can be reached based on the validation result with TCCON measurements.

Analysis of XCO_2 retrieval sensitivity using simulated Chinese Carbon Satellite(TanSat) measurements

We present a study on the retrieval sensitivity of the column-averaged dry-air mole fraction of CO2(XCO2) for the Chinese carbon dioxide observation satellite(TanSat) with a full physical forward model and the optimal estimation technique. The forward model is based on the vector linearized discrete ordinate radiative transfer model(VLIDORT) and considers surface reflectance, gas absorption, and the scattering of air molecules, aerosol particles, and cloud particles. XCO2 retrieval errors from synthetic TanSat measurements show solar zenith angle(SZA), albedo dependence with values varying from 0.3 to 1 ppm for bright land surface in nadir mode and 2 to 8 ppm for dark surfaces like snow. The use of glint mode over dark oceans significantly improves the CO2 information retrieved. The aerosol type and profile are more important than the aerosol optical depth, and underestimation of aerosol plume height will introduce a bias of 1.5 ppm in XCO2. The systematic errors due to radiometric calibration are also estimated using a forward model simulation approach.