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| 1 | Influence of Atmospheric Particulate Matter on Ozone in Nanjing,China:Observational Study and Mechanistic Analysis显示文摘Particulate matter with diameters of 2.5 μm or smaller(PM_(2.5)) and ozone(O_3) are major pollutants in the urban atmosphere. PM_(2.5) can affect O_3 by altering the photolysis rate and heterogeneous reactions. However, these two processes and their relative importance remain uncertain. In this paper, with Nanjing in China as the target city, we investigate the characteristics and mechanism of interactions between particles and O_3 based on ground observations and numerical modeling.In 2008, the average concentrations of PM_(2.5) and O_3 at Caochangmen station are 64.6 ± 47.4 μg m^(-3) and 24.6 ± 22.8 ppb,respectively, while at Pukou station they are 94.1 ± 63.4 μg m^(-3) and 16.9 ± 14.9 ppb. The correlation coefficient between PM_(2.5) and O_3 is -0.46. In order to understand the reaction between PM_(2.5) and O_3, we construct a box model, in which an aerosol optical property model, ultraviolet radiation model, gas phase chemistry model, and heterogeneous chemistry model,are coupled. The model is employed to investigate the relative contribution of the aforementioned two processes, which vary under different particle concentrations, scattering capability and VOCs/NOxratios(VOCs: volatile organic compounds;NOx: nitric oxide and nitrogen dioxide). Generally, photolysis rate effect can cause a greater O_3 reduction when the particle concentrations are higher, while heterogeneous reactions dominate O_3 reduction with low-level particle concentrations.Moreover, in typical VOC-sensitive regions, O_3 can even be increased by heterogeneous reactions. In Nanjing, both processes lead to O_3 reduction, and photolysis rate effect is dominant. Our study underscores the importance of photolysis rate effect and heterogeneous reactions for O_3, and such interaction processes should be fully considered in future atmospheric chemistry modeling. | Yawei QU Tijian WANG Yanfeng CAI Shekou WANG Pulong CHEN Shu LI Mengmeng LI Cheng YUAN Jing WANG Shaocai XU | 2018 | Advances in Atmospheric Sciences2018，35，11： | 33 |
| 2 | Encapsulating soluble active species into hollow crystalline porous capsules beyond integration of homogeneous and heterogeneous catalysis显示文摘Homogeneous molecular catalysts and heterogeneous catalysts possess complementary strengths,and are of great importance in laboratory/commercial procedures.While various porous hosts,such as polymers,carbons,silica,metal oxides and zeolites,have been used in an attempt to heterogenize homogeneous catalysts,realizing the integration of both functions at the expense of discounting their respective advantages,it remains a significant challenge to truly combine their intrinsic strengths in a single catalyst without compromise.Here,we describe a general template-assisted approach to incorporating soluble molecular catalysts into the hollow porous capsule,which prevents their leaching due to the absence of large intergranular space.In the resultant yolk(soluble)–shell(crystalline)capsules,the soluble yolks can perform their intrinsic activity in a mimetic homogeneous environment,and the crystalline porous shells endow the former with selective permeability,substrate enrichment,size-selective and heterogeneous cascade catalysis,beyond the integration of the respective advantages of homogeneous and heterogeneous catalysts. | Guorui Cai Meili Ding Qianye Wu Hai-Long Jiang | 2020 | National Science Review2020，7，1： | 12 |
| 3 | Heterogeneous reaction of NO_2 on the surface of NaCl particles显示文摘The heterogeneous reaction of NO2 on NaCl particles has been investigated with the new sample preparation and the mode of gas-solid free diffusion. Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) is used to characterize the adsorbed products in situ, combined with Ion Chromatographic (IC), X-ray Photoelectron Spectroscopy (XPS) and Scan Electron Micros- copy (SEM). Our results indicate that the reaction is not limited to the surface of the NaCl particles, but penetrated into the upper layers. Surface reactive sites determine the reaction. Kinetic measurements show that nitrate formation on sodium chloride is second order in NO2 concentration and reactive uptake coefficient is (1.54 ± 0.70) × 10?5. | LI Hongjun ZHU Tong DING Jie CHEN Qi XU Bingye | 2006 | Science China Chemistry2006，49，4： | 9 |
| 4 | Heterogeneous reactions of gaseous methanesulfonic acid with NaCl and sea salt particles显示文摘Methanesulfonic acid(MSA) has been identified as one of the most important intermediate products of DMS reactions in the atmosphere.Although considerable amounts of MSA have been found in the ma-rine boundary layer,little is known about the interaction of gaseous MSA with sea salt particles.To understand the fate of MSA in the atmosphere and its potential importance in atmospheric chemistry,the heterogeneous reactions of gaseous MSA with micron-scale NaCl and sea salt particles were studied using diffuse reflectance infrared Fourier transform spectrometry,X-ray photoelectron spectroscopy,and scanning electron microscopy.The CH3SO3Na and CH3SO3-were the major products of the condensed phase of the reaction of gaseous MSA with NaCl and with sea salt particles.The steady-state uptake coefficient was determined to be(5.94±2.32)×10-7(1 σ) for the reaction of gaseous MSA with NaCl particles and(2.23±1.25)×10-7(1 σ) for the reaction of gaseous MSA with sea salt parti-cles.The heterogeneous reaction of MSA with NaCl particles was found to be first-order for MSA.The reaction mechanisms were discussed. | TANG MingJin ZHU Tong | 2009 | Science China Chemistry2009，52，1： | 7 |
| 5 | Heterogeneous reaction of formaldehyde on the surface of TiO_2 particles显示文摘The heterogeneous reaction of formaldehyde (HCHO) on the surface of titanium dioxide (TiO2) was investigated in situ using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) combined with ion chromatography (IC),X-ray diffraction (XRD),and transmission electron microscopy (TEM).Formate,dioxymethylene,methoxy,and polyoxymethylene were observed in the infrared spectra of TiO2 particles during the reaction.On the surface of TiO2,the adsorbed HCHO was first oxidized to dioxymethylene and further oxidized to formate.The effects of temperature and ultraviolet radiation (UV) on the reaction products and reactive uptake coefficients were studied,and the results indicate that the reaction rate can be accelerated at increasing temperatures as well as under UV.The heterogeneous reaction mechanisms of HCHO on the surface of TiO2 in the dark and under UV irradiation are proposed.Kinetic measurements show that formate formation on TiO2 is second order in HCHO concentration and the initial reactive uptake coefficients at room temperature calculated with the Brunauer-EmmettTeller specific surface area are (0.5-5) × 10-8 ([HCHO]:1 × 1013-2 × 10 14 molecules/cm3).A linear function relationship exists between the uptake coefficient and the concentration.The apparent activation energy of the reaction was also determined. | XU BingYe 1,2,ZHU Tong 1,TANG XiaoYan 1 & SHANG Jing 1 1 State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China 2 Zhejiang Province Environmental Monitoring Center,Hangzhou 310012,China | 2010 | Science China Chemistry2010，53，12： | 5 |
| 6 | Heterogeneous reactions of gaseous methanesulfonic acid with calcium carbonate and kaolinite particles显示文摘Heterogeneous reactions of gaseous methanesulfonic acid (MSA) with calcium carbonate (CaCO3) and kaolinite particles at room temperature were investigated using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Methanesulfonate (MS-) was identified as the product in the condensed phase,in accordance with the product of the reaction of gaseous MSA with NaCl and sea salt particles.When the concentration of gaseous MSA was 1.34 × 10-13 molecules cm-3,the uptake coefficient was (1.21 ± 0.06) × 10-8 (1) for the reaction of gaseous MSA with CaCO3 and (4.10 ± 0.65) × 10 10 (1) for the reaction with kaolinite.Both uptake coefficients were significantly smaller than those of the reactions of gaseous MSA with NaCl and sea salt particles. | TANG MingJin,LI MengQiu & ZHU Tong State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China | 2010 | Science China Chemistry2010，53，12： | 1 |
| 7 | Fabrication of zinc-based coordination polymer nano-cubes and post-modification through copper decoration显示文摘Coordination polymer particles (CPPs) with a high degree of porosity andmulti-functional reaction sites are promising for diverse applications. Theintegration of open sites favorable for the post-modification of CPPs presents aunique opportunity for the rational design of inorganic materials with target-oriented functions. Herein, we report a shape-controllable synthetic protocolfor zinc-based coordination polymer nanocubes (Zn-CPNs). In the synthesis,2,6-bis[(4-carboxyanilino)carbonyl] pyridine ([N3]) ligand is employed as anefficient shape-directing modulator to control the size and shape of Zn-CPNs.More importantly, the [N3] ligand provides metal binding sites suitable for thedecoration of other functional metals such as copper ions. The copper-modifiedZn-CPNs (Cu_Zn-CPNs) show good activities in a heterogeneous catalyticreaction. | Ngoc Minh Tran Hien Duy Mai Hyojong Yoo | 2018 | Nano Research2018，11，11： | 1 |
| 8 | Fenton-like oxidation of azo dye in aqueous solution using magnetic Fe3O4-MnO2 nanocomposites as catalysts显示文摘In order to overcome the drawback of the low degree of separation from an aqueous solution of MnO_2, Fe_3 O_4-MnO_2 core-shell nanocomposites were used as heterogeneous Fenton-like catalysts for the removal of acid orange 7. On the basis of the catalyst characterization, the catalytic ability of the as-synthesized nanocomposites was examined. The results showed that Fe304-Mn02 core-shell nanocomposites had greater catalytic ability than Fe_3 O_4 or MnO_2 used alone. Meanwhile, the catalyst dosage, H_2 O_2 dosage, temperature, and initial pH had significant effects on the removal of acid orange 7. A high degree of stability and reusability were exhibited by Fe_3 O_4-MnO_2 core-shell nanocomposites. Both HO· and HO_2· were generated in the reaction and HO· was the main radical for the removal of acid orange 7. A mechanism for H_2 O_2 catalytic decomposition using Fe_3 O_4-MnO_2 core-shell nanocomposites to produce HO·is proposed. | Zhen-dong Fang Kai Zhang Jie Liu Jun-yu Fan Zhi-wei Zhao | 2017 | Water Science and Engineering2017，10，4： | 1 |
| 9 | Chemistry and Application of Phosphonium and Arsonium Ylides (XV——A Facile Synthesis of Dimethyl 3,7-Diperfluoroalkyl-2,4,7-Nonatriendioates显示文摘We reported the stereoselectlve synthesis of fluorine-containing trisubstituted ethylenes(4) by hydrolysis of the adducts(3) which are the products of the reactions of some stable phosphonium or arsonium ylides with methyl 2-perfluoroalkynoates(2). | Zhang Pingsheng, Ding Weiyu and Cao Weiguo (Department of Chemistry, Shanghai University of Science and Technology, Shanghai) | 1990 | Chemical Research in Chinese Universities1990，6，2： | 0 |
| 10 | Using Goethite as a Heterogeneous Fenton Catalyst for The Removal of Tetracycline Hydrochloride: Effects of Its Adsorptive and Reductive Activities显示文摘The removal of the antibiotic compound tetracycline hydrochloride (TC) was investigated by using goethite/H2O2 as a heterogeneous Fenton reagent. Five principle operational parameters, especially solution pH value, were taken into account to investigate how the heterogeneous Fenton process factors mediated the TC removal. This process was effective but seriously impacted by the pH value and temperature, as well as the dosages of α-FeOOH, TC and H2O2. Very interestingly, the acidic and alkaline aqueous medium conditions were both very favorable due to the occurrence of transformation of Fe(III) to Fe(II) on goethite surfaces reduced by TC at pH 3.0~4.0 even though with a low adsorption capacity of TC because its maximum adsorption of negatively charged form occurred at pH around 8.0[1], thereby greatly promoting the TC Fenton oxidative elimination. However, a rapid initial TC decay was observed at the first 5 min, followed by a much slower retardation stage, which was likely because the reductive transformation of Fe(III) to Fe(II) by TC in the solution was inhibited as the Fenton reaction proceeded. Moreover, the hydroxyl radical scavenger t-butanol addition can decrease the removal rate of TC in the goethite/H2O2 system to a certain extent. This further indicated that the main reactive species in this process were hydroxyl radicals[2]. All the goethite-catalysed heterogeneous Fenton reactions are responsible for the TC removal following the Langmuir-Hinshelwood model, were well fitted to pseudo-first order kinetics (R2>0.99), and their apparent activation energy (E) for this Fenton-like reaction was 31.86 kJ mol 1, a low value that is highly consistent with the ease of TC decay greatly enhanced by the temperature rise, indicated that the interfacial controlling interactions such as a proton induced solubilization and a reductive dissolution of goethite can clearly improve its Fenton catalytic activity[3], and these dissolution processes may not be effective in some cases, while the TC adsorption process may always play an important role to control the TC removal rate during the Fenton reaction. | WU Honghai JIANG Fenfen GUAN Yufeng CHEN Xiaoling | 2013 | 矿物学报2013，33，S1： | 0 |
| 11 | Lattice Boltzmann Simulation of a Gas-to-Solid Reaction and Precipitation Process in a Circular Tube显示文摘The lattice Boltzmann method(LBM)is used to simulate the growth of a solid-deposit on the walls of a circular tube resulting from a gas-to-solid reaction and precipitation process.This process is of particular interest for the design of reactors for the production of hydrogen by the heterogeneous hydrolysis of steam with Zn vapor in the Zn/ZnO thermochemical cycle.The solid deposit of ZnO product on the tube wall evolves in time according to the temporally-and axially-varying convective-diffusive transport and reaction of Zn vapor with steam on the solid surface.The LBM is wellsuited to solving problems with coupled flow,heat and mass transfer in a time-evolving domain.Here,a D2Q9 axisymmetric multiple-relaxation-time(MRT)lattice Boltzmann scheme is used to simulate incompressible fluid transport while a D2Q5 axisymmetric MRT lattice Boltzmann scheme is used to simulate the convective-diffusive transport of Zn vapor.The model is first validated against several analytical solutions,followed by a parametric study to understand the effect of Reynolds,Schmidt,and Damk?hler numbers on the time evolution of the ZnO deposition profile along the tube axis.The axial location of the fastest deposition is found to increase with increasing Peclet number,and decrease with increasing Damk?hler number,with no independent effect from the Schmidt number.When the reaction kinetics are assumed to increase along the tube axis due to nonisothermal tube wall temperature,a second peak in the deposition profile can be observed for sufficiently low values of Da/Pe. | Matthew D.Lindemer Suresh G.Advani Ajay K.Prasad | 2018 | Computer Modeling in Engineering & Sciences2018，，12： | 0 |
| 12 | KINETIC EQUATIONS WITH VARIATION OF LIQUID REACTANT CONCENTRATION显示文摘For two common types of liquid-solid heterogeneous reactions,the kinetic equations havebeen established which involved both the variation of liquid reactant concentration and the va-riation of solid reactant geornetry with the reaction time.The experimental results show thatthe kinetic equations are more accurate and reasonable than those appeared in previous litera-tures.Moreover,they are also suitable for gas-solid heterogeneous reactions in principle. | YIN Qunsheng ZHAO Tiancong ZHONG Tingke LIN Ruoya Central South University of Technology,Changsha,China YIN Qunsheng Lecturer Dept.of Metallurgy,Central South University of Technology Changsha 410083,China | 1990 | Acta Metallurgica Sinica(English Letters)1990，3，10： | 0 |
| 13 | Kinetics of α-FeO(OH)Formation in Weak Acidic Medium显示文摘The kinetics of α-FeO(OH) formation in weakacidic medium was studied.The effects of the initialconcentration,temperature,pH value,partial pres-sure of oxygen,air flow rate and agitating intensityon the oxidation rate of Fe(OH)2 suspensions havebeen investigated.It is confirmed that the reactionorder for Fe(Ⅱ) is zero at the stage of α-FeO(OH)seeds formation,and about 0.5 at the stage of theseeds growth,and in the whole process partial pres-sure of oxygen appears in first order.The activationenergy is determined.The dissolution-oxidationequilibrium which exists in the process of seedsformation has been suggested,by which the zeroorder reaction for Fe(Ⅱ) and the plateau in thepH-t curve were explained.Physical process is therate-determining step of the heterogeneousreaction.The study on the kinetics of α-FeO(OH)formation may provide some fundamental informa-tion for the reactor design,the engineering amplifi-cation and the optimization control in the industrialprocess. | 张懿 王颖霞 华彤文 | 1991 | Journal of Materials Science & Technology1991，7，1： | 0 |
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