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kinetic and thermodynamic effects of moisture content and temperature on the ammonia volatilization of soil fertilized with urea

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International Journal of Agricultural and Biological Engineering 2017年第6期10卷 134-143页

作者： Lei Tao Guo Xianghong Ma Juanjuan Sun Xihuan Feng Yang Wang Hongyu College of Water Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Jinzhong University Jinzhong 030600ShanxiChina

The traditional qualitative analysis of the individual factors on the kinetic and thermodynamic parameters cannot sufficiently reveal the mechanism underlying ammonia volatilization in *** study aimed to determine the effects of temperature,moisture content,and their interaction on the kinetic and thermodynamic parameters,which revealed the key control mechanism underlying ammonia volatilization,modified the traditional Arrhenius model,and established a quantitative prediction model of cumulative NH_(3)-N loss(CNL).Laboratory culture experiments were conducted under different temperatures(T)(15℃,20℃,25℃and 35℃)and moisture contents(θ)(60%,80%,and 100%field capacities).Soil ammonia volatilization was also measured every 2 *** showed that the effects of individual factors and their interaction on the values of reaction rate(K_(N)),Activation free energy(ΔG),and activation entropy(ΔS)followed the descending order of T>θ>T·θ,whereas those of activation enthalpy(ΔH)and activation degree(lgN)followed the descending order ofθ>T>T·θ.The interaction showed significant effect on K_(N)value and insignificant effect on all the thermodynamic *** effects of water and temperature were mainly observed during the preparatory stage and the most critical transition state stage of the chemical reaction,*** thatΔH>0,ΔG>0,andΔS>0,ammonia volatilization is found to be an endothermic reaction controlled by *** new K_(N)(T)-2 model with the determination coefficient(R^(2))of 0.999 was more accurate than the traditional Arrhenius model with the R^(2)of *** new NH_(3)(T,θ)model with the mean absolute percentage error(MAPE)of 4.17%was more accurate than the traditional NH_(3)(T)model with the MAPE of 7.11%.These results supplemented the control mechanism underlying ammonia volatilization in soil fertilized with urea and improved the prediction accuracy of CNL.

关键词： soil ammonia volatilization kinetic parameters thermodynamic parameters soil moisture content urea fertilizer Arrhenius model NH3(T,θ)model

Thermal decomposition analysis of coal-waste sludge and coal-sunflower seed husk blends

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Journal of Harbin Institute of Technology(New Series) 2010年第5期17卷 641-646页

作者：王淑彦李晓琦刘文铁宋承毅王春生董群 School of Petroleum Engineering Northeast Petroleum University School of Energy Science and Engineering Harbin Institute of Technology Daqing Oil Field Design Institute School of Chemistry and Chemical Engineering Northeast Petroleum University

The thermal decomposition analysis of coal-pharmaceutical waste sludge,coal-sewage waste sludge blends and coal-sunflower seed husk blends are studied by TG dynamic runs at the heating rate of 20 ℃/min within the temperature range of 25 ℃-900 ℃.The effect of different kinetic models on the determination of kinetic parameters of thermal decomposition has been *** show that for coal-pharmaceutical sludge blend,coal-sewage sludge blend and coal-sunflower seed husk blend the optimal model functions are the three-dimensional diffusion reaction,2-dimensional and 3-diemensional nucleation and growth reactions,*** Arrhenius kinetic parameters of the pre-exponential factor and activation energy of blends,as well waste sludge and sunflower seed husk only are proposed.

关键词： pyrolysis coal-waste sludge blends thermogravimetric analysis model function kinetic parameters

Comparative Studies of Substrate and Inhibitor Specificity of Glutathione S-Transferases in Six Tissues of Oxya chinensis(Thunberg)(Orthoptera:Acrididae)

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Agricultural Sciences in China 2008年第4期7卷 462-468页

作者： WU Hai-hua ZHU Kun-yan GUO Ya-ping ZHANG Xiao-min MA En-bo Institute of Applied Biology Shanxi University Taiyuan 030006 P.R.China Department of Entomology Kansas State University Manhattan 66506 USA

Specific activity, substrate specificity, and kinetic parameters （Km and Vmax） of glutathione S-transferases （GSTs） towards three substrates, 1-chloro-2,4-dinitrobenzene （CDNB）, 1,2-dichloro-4-nitrobenzene （DCNB）, and p-nitrobenzene chloride （pNBC） were investigated in six tissues （foregut, midgut, hindgut, fat body, hemolymph, and muscle） of Oxya chinensis. In addition, the inhibition in vitro （ethacrynic acid, and Cibacron Blue 3GA） of Oxya chinensis in the six tissues was also investigated. Glutathione S-transferase activity was detected in all the six tissues examined. The rank order of GST activities towards CDNB was fat body 〉 midgut 〉 hindgut 〉 muscle 〉 foregut 〉 hemolymph both in females and males. Glutathione S-transferase activities in the fat body in females and males were 1.3- to 10.4-fold and 1.1- to 10.0- fold higher than those in the other tissues. The rank order of GST activities towards the other substrates changed slightly. From these results, it was inferred that GSTs in the fat body and midgut played important roles in detoxifying xenobiotics including insecticides and plant allelochemicals in O. chinensis. In the three substrates examined, CDNB seemed to be the best substrate, followed by pNBC and DCNB. The kinetic parameters of GSTs were different among the six tissues. This suggested that GSTs in different tissues have various affinities and catalytic efficiency to substrates. In vitro inhibition study showed that the median inhibition concentration （IC50） values of the two inhibitors to GSTs from the six tissues were different. The results suggested that the two inhibitors have different inhibition potency to GSTs from the different tissues. The observed changes in kinetic parameters and inhibition in vitro among the six tissues of the insect might suggest that the number and structure of isoenzymes and their rate of expression varied for the different tissues.

关键词： Oxya chinensis glutathione S-transferase (GST) tissue distribution kinetic parameters inhibition in vitro

Conductive proteins-based extracellular electron transfer of electroactive microorganisms

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Quantitative Biology 2023年第4期11卷 405-420页

作者： Junqi Zhang Zixuan You Dingyuan Liu Rui Tang Chao Zhao Yingxiu Cao Feng Li Hao Song Frontier Science Center for Synthetic Biology(Ministry of Education) Key Laboratory of Systems Bioengineeringand School of Chemical Engineering and TechnologyTianjin UniversityTianjinChina

Electroactive microorganisms(EAMs)could utilize extracellular electron transfer(EET)pathways to exchange electrons and energy with their external *** cytochrome proteins and nanowires play crucial roles in controlling electron transfer rate from cytosol to extracellular *** previous studies elucidated how the c-type cytochrome proteins and conductive nanowires are synthesized,assembled,and engineered to manipulate the EET rate,and quantified the kinetic processes of electron generation and ***,we firstly overview the electron transfer pathways of EAMs and quantify the kinetic parameters that dictating intracellular electron production and ***,we systematically review the structure,conductivity mechanisms,and engineering strategies to manipulate conductive cytochromes and nanowire in ***,we outlook potential directions for future research in cytochromes and conductive nanowires for enhanced electron *** article reviews the quantitative kinetics of intracellular electron production and EET,and the contribution of engineered c-type cytochromes and conductive nanowire in enhancing the EET rate,which lay the foundation for enhancing electron transfer capacity of EAMs.

关键词： c-type cytochromes conductive nanowires extracellular electron transfer kinetic parameters synthetic biology

Determination of hydrocarbon generation potential of a non-isothermal pyrolysis of Faraghun and Sarchahan Formations in Coastal Fars and the Persian Gulf,Iran

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China Geology 2021年第4期4卷 644-657页

作者： Younes Jalilian Mohammad Hossein Saberi Faculty of New Science and Technology Department of Petroleum EngineeringSemnan UniversitySemnan 35131-19111Iran

Source rock assessment is a key step in any petroleum exploration *** results of Rock-Eval analysis showed that Sarchahan Formation was in the late oil window,while the Faraghun and Zakeen Formations were just in the early stages of the oil ***,Sarchahan,Zakeen and Faraghun Formations exhibited different kerogen types(types-Ⅱ,types-Ⅲand type-Ⅲ,respectively).Refining the kinetic parameters using the OPTKIN software,the error function returned error values below 0.1,indicating accurate optimization of the kinetic *** on the obtained values of activation energy,it was clear that Sarchahan Formation contained type-Ⅱkerogen with an activation energy of 48-52 kcal/mol,while Zakeen and Faraghun Formations contained type-III kerogen with activation energies of 70-80 kcal/mol and 44-56 kcal/mol,*** geographical distribution of the samples studied in this work,it was found that the organic matter(OM)quantity and quality increased as one moved toward the Coastal Fars in Sarchahan *** same trend was observed as one moved from the southern coasts of Iran toward the shaly and coaly portions of Faraghun Formation in the center of the Persian Gulf.

关键词： kinetic parameters Rock-Eval pyrolysis Hydrocarbon potential Source rock Sarchahan Formation Faraghun Formation Zagros Basin Persian Gulf Iran

Study on the Atomization Process of Lithium in Electrothermal Atomic Absorption Spectrometry

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Chemical Research in Chinese Universities 1989年第1期5卷 26-33页

作者： Yan Xiuping(Department of Chemistry, Taizhou Teachers College, Taizhou)Lin Tiezheng(Dalian Institute of Chemical Physics, Academia Sinica)

A new method for determining the kinetic order and activation energy for atom formation in electrothermal atomic absorption spec-trometry is proposed. The assumption of first order kinetics for atom formation and the steady-state approximation which appeared in the previous models is avoided in the proposed method. The kinetic parameters for atom formation of Li have been obtained, and the effect of the amount of analysed sample, ashing temperature, atomization temperature, heating rate, gas flow and tube surface on the atomization of Li has also been investigated.

关键词： Atomic absorption Atomization peocess kinetic parameters

A new kinetic model for direct CO2 hydrogenation to higher hydrocarbons on a precipitated iron catalyst:Effect of catalyst particle size

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Journal of Energy Chemistry 2017年第3期26卷 359-367页

作者： Ali Nakhaei Pour Mohammad Reza Housaindokht Department of Chemistry Faculty of ScienceFerdowsi University of MashhadP.O.Box:***MashhadIran

The kinetic of the direct COhydrogenation to higher hydrocarbons via Fischer–Tropsch synthesis（FTS）and reverse water-gas shift reaction（RWGS） mechanisms over a series of precipitated Fe/Cu/K catalysts with various particle sizes was studied in a well mixed, continuous spinning basket reactor. The iron catalysts promoted with copper and potassium were prepared via precipitation technique in various alcohol/water mixtures to achieve a series of catalyst particle sizes between 38 and 14 nm. A new kinetic model for direct COhydrogenation was developed with combination of kinetic model for FTS reaction and RWGS equilibrium condition. For estimate of structure sensitivity of indirect COhydrogenation to higher hydrocarbons, the kinetic parameters of developed model are evaluated for a series of iron catalysts with various particle sizes. For kinetic study a wide range of syngas conversions have been obtained by varying experimental conditions. The results show that the new developed model fits favorably with experimental data. The values of activation energies for indirect COhydrogenation reaction are fall within the narrow range of 23–16 kJ/mol.

关键词： Fischer–Tropsch synthesis Carbon dioxide hydrogenation Iron-based catalyst kinetic parameters

kinetics of celestite conversion to acidic strontium oxalate hydrate in aqueous solution of oxalic acid

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Transactions of Nonferrous Metals Society of China 2019年第6期29卷 1332-1345页

作者： Mert ZORAGA Cem KAHRUMAN Ibrahim YUSUFOGLU Istanbul University-Cerrahpasa Engineering FacultyMetallurgical and Materials Engineering Department

Conversion of SrSO4 to acidic strontium oxalate hydrate(H[Sr(C2O4)1.5(H2O)]) in aqueous H2C2O4 solutions proceeds as a consecutive reaction. In the first step of the consecutive reaction, SrSO4 reacts with H2C2O4 and pseudomorphic conversion to SrC2 O4·H2O occurs. In the second step, SrC2 O4·H2O reacts with H2C2O4 to form H[Sr(C2 O4)1.5(H2O)]. Sr(HC2 O4)(C2 O4)0.5·H2 O crystallizes during cooling of the reaction mixture to room temperature if the solution reaches the saturation concentration of (H[Sr(C2O4)1.5(H2O)]. The aims of this study are the derivation of reaction rate equations and the determination of the kinetic parameters such as pre-exponential factor, apparent activation energy and order of H2C2O4 concentration for each reaction *** conversions of SrSO4 were calculated using the quantitative amounts of dissolved S and Sr. It was determined that the reaction rate increased at the initial time of reaction by increasing the temperature using solutions with approximately same H2C2O4 concentrations. The reaction extends very slowly after a certain time in solutions with low H2C2O4 concentration and ends by the formation of a protective layer of SrC2O4-H2O around the surfaces of solid particles. Fractional conversion of SrSO4 is increased by increasing concentration of H2C2O4 at constant temperature. kinetic model equations were derived using shrinking core model for each step.

关键词： celestite concentrate pseudomorphic conversion rate equations kinetic parameters conversion reaction

Full-scale application of microbial agent on in-situ sludge reduction

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Journal of Southeast University(English Edition) 2016年第4期32卷 502-507页

作者：谢慧芳张晋华辛文力胡灿洋严梅张青贺启环周建成南京理工大学环境与生物工程学院南京210094 东南大学化学化工学院南京211189

The full-scale application of Tx-1, a multifunctional microbial agent, was carried out for 8 months in an anoxic/oxic（A/O） municipal wastewater treatment process. The results show that the Tx-1 dosed system can obtain good effluent characteristics while minimizing sludge production and energy consumption. The total phosphorus（TP） is lower than0. 5 mg/L in effluent without any chemical regent added. The discharged dry sludge per 10 000 m^3 wastewater Dwat decreases from 1. 4 to 0. 5 t. For per cubic meter wastewater, the air supply decreases from 6. 0 to 5. 1 m^3 and the electricity consumption decreases from 0. 412- 0. 425 kW·h to 0. 331 kW·h. The addition of Tx-1 can improve the substrate removal constant and decrease the microorganism growth yield coefficient of activated sludge. At the same time,the structure of the microbial community changes and the biodiversity increases by adding Tx-1. The abundance of polyphosphate accumulating organisms（PAO）, Comamonadaceae and Tetrasphaera, increased. Effective microbial agent is a potential way to combine in-situ sludge minimization with contaminants removal.

关键词： wastewater treatment dosed anoxic/oxic(A/O) process diversity of microbial community kinetic parameters