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Science China(Technological Sciences) 2015年第2期58卷 258-265页

作者： LIU Meng Qi NIU Sheng Li LU Chun Mei LI Hui HUO Meng Jia School of Energy and Power Engineering Shandong University

The catalytic performance of carbide slag in transesterification is investigated and the reaction kinetic parameters are calculated. After being activated at 650℃, calcium compounds of carbonate and hydroxide in the carbide slag are mainly transformed into calcium oxide. The activated carbide slag utilized as the transesterification catalyst is characterized by X-ray diffraction （XRD）, attenuated total reflectance-Fourier transform infrared spectroscopy （ATR-FTIR）, nitrogen adsorption-desorption and the Hammett indicator method. Compared with the carbide slag activated at 700 and 800℃, the largest surface area of 22.63 m2g^-1, the smallest particle size of 265.12 nm and the highest catalytic efficiency of the carbide slag activated at 650℃ guarantee its capacity in catalyzing transesterification. Then, the influences of activated temperature （Ta）, molar ratio of methanol to oil （γ）, catalyst added amount （ζ）, reaction temperature （Tr） and reaction time （τ） on the catalytic performance are investi- gated. Under the optimal transesterification condition of Ta=650℃, γ=15, ζ=3%, Tr=60℃ and τ=-110 rain, the catalytic efficiency of 92.98% can be achieved. Finally, the kinetic parameters of transesterification catalyzed by the activated carbide slag are calculated, where activation energy （E） is 68.45 kJ mol^-1 and pre-exponential factor （k0） is 1.75×10^9 min^-1. The activated carbide slag shows better reused property than calcium hydroxide.

关键词： transesterification catalyst carbide slag kinetic parameters

Thermochemical Aspects of Activated Ammonium Perchlorates with Superior Thermal Stability,Decomposition Enthalpy,Propagation Index,and Decomposition kinetic parameters

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Journal of Thermal Science 2021年第6期30卷 2196-2201页

作者： SHERIF Elbasuney M.Yehia SHUKRI Ismael SHERIF Farag AHMED Saleh GHARIEB S.El-Sayyad Head of Nanotechnology Research Center Military Technical College(MTC)Cairo 11646Egypt School of Chemical Engineering Military Technical College(MTC)Cairo 11646Egypt Science and Technology Center of Excellence Cairo 11646Egypt Drug Radiation Research Department National Center for Radiation Research and Technology(NCRRT)Egyptian Atomic Energy Authority(EAEA)Cairo 11646Egypt

Ammonium perchlorate(AP)includes oxidizing and reducing elements on the same *** can act as an efficient oxidizer and mono-propellant as *** this study,AP experienced crystallographic phase change from orthorhombic centrosymmetric to non-centrosymmetric under controlled isothermal heat *** diffractograms confirmed this crystallographic phase *** thermal behaviour of activated AP had been investigated using *** AP demonstrated high chemical stability with an increase in endothermic phase transition enthalpy by 170%.The enthalpy of the subsequent two main exothermic decomposition reactions was increased by 250%.Whereas AP demonstrated total decomposition enthalpy of 733 J/g,activated AP showed 2614 J/*** AP can secure self-sustained response at a high *** index(combustion enthalpy/ignition temperature)was employed to assess self-sustained reaction *** AP demonstrated high propagation index of 8.7 compared with 2.5 for un-activated *** decomposition kinetic parameters had investigated using Kissinger and KAS *** AP showed an increase in activation energy by 89%using the Kissinger method;kinetic parameters using the KAS method were in good agreement with the Kissinger *** can have concluded that AP with novel kinetic decomposition parameters for enhanced safety storage and high combustion characteristics has evolved.

关键词： solid propellants oxidizers thermal behavior kinetic parameters activation energy

Thermoluminescence glow curve analysis and kinetic parameters of Dy-doped BaSi_(2)O_(5)phosphor

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Journal of Rare Earths 2022年第2期40卷 234-242,I0002页

作者： Y.Alajlani N.Can Physics Department Jazan UniversityP.O.Box 114Jazan45142Saudi Arabia Department of Physics Faculty of Arts and SciencesManisa Celal Bayar UniversityMuradiye-Manisa45010Turkey

In this paper,Dy^(3+)incorporated BaSi_(2)O_(5)phosphors were synthesized by gel co mbustion method and characterized by X-ray diffraction(XRD).The effects of various heating rate s on thermoluminescence(TL)kinetics and glow peak temperatures of Dy^(3+)incorporated BaSi_(2)O_(5)phosphors exposed toβirradiation at room temperature were *** glow curves of the phosphor exposed toβ-irradiation(0.1-100 Gy)consist of four main peaks located at 87,130,271,and 327℃and exhibit a good linearity between 0.1 and100 *** experimental techniques including variable heating rate(VHR),repeated initial rise(RIR),peak shape(PS)and computerized glow curve deconvolution(CGCD)were employed to determine TL kinetic *** findings indicate that the TL glow peaks of the phosphor obey first-order *** of the main dosimetric peaks through the techniques mentio ned above indicates that activation energies(E)and pre-exponential factor(s)are in the range of 0.80-1.50 eV and 1.15×10^(8)-3.28×10^(13)s^(-1).Additionally,it is found that the temperature of the glow peaks shifts toward the higher temperatures and the TL intensity smoothly decreases as the heating rate *** effect on the TL intensities and glow peak temperatu res of the heating rate is discussed in terms of thermal quenching.

关键词： BaSi_(2)O_(5) Dy^(3+) Gel combustion XRD Thermoluminescence kinetic parameters

Comparison of Seven kinetic Equations for K Release and Application of kinetic parameters

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Pedosphere 2007年第1期17卷 124-129页

作者： Lü Xiao-Nan XU Jian-Ming MA Wan-Zhu LU Yun-Fu Institute of Soils and Fertilizers Zhejiang Academy of Agricultural Sciences Hangzhou 310021 （China） College of Environmental Sciences and Resources Zhejiang University Hangzhou 310029 （China）

Corn field experiments with two treatments, NP and NPK, where N in the form of urea, P in the form of calcium phosphate, and K in the form of KCl were applied at rates of 187.5, 33.3, and 125 kg ha^-1, respectively, on soils derived from Quaternary red clay were conducted in the hilly red soil region of Zhejiang Province, China. Plant grains and stalks were collected for determination of K content. Seven equations were used to describe the kinetics of K release from surface soil samples taken before the corn experiments under electric field strengths of 44.4 and 88.8 V cm^-1 by means of electro-ultrafiltration （EUF） and to determine if their parameters had a practical application. The second-order and Elovich equations excellently described K release; the first-order, power function, and parabolic diffusion equations also described K release well; but the zero-order and exponential equations were not so good at reflecting K release. Five reference standards from the field experiments, including relative grain yield （yield of the NP treatment/yield of the NPK treatment）, relative dry matter yield （dry matter of the NP treatment/dry matter of the NPK treatment）, quantity of K uptake in the NP treatment （no K application）, soil exchangeable K, and soil HNO3-soluble K, were used to test the effectiveness of equation parameters obtained from the slope or intercept of these equations. Correlations of the ymax （the maximum desorbable quantity of K） in the second-order equation and the constant b in the first-order and Elovich equations to all five reference standards were highly significant （P ≤ 0.01）. The constant a in the power function equation was highly significant （P 〈 0.01） for four of the five reference standards with the fifth being significant （P ≤ 0.05）. The constant b in the parabolic equation was also significantly correlated （P ≤ 0.05） to the relative grain yield and soil HNO3-soluble K. These suggested that all of these parameters could be used to estimate t

关键词： corn K release kinetic equation kinetic parameters

Measuring the kinetic parameters of saltating sand grains using a high-speed digital camera

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Science China(Physics,Mechanics & Astronomy) 2014年第6期57卷 1137-1143页

作者： ZHANG Yang WANG Yuan JIA Pan Department of Fluid Machinery and Engineering Xi'an Jiaotong University

A high-speed digital camera is used to record the saltation of three sand samples(diameter range:300–500,200–300 and100–125μm).This is followed by an overlapping particle tracking algorithm to reconstruct the saltating trajectory and the differential scheme to abstract the kinetic parameters of saltating *** velocity results confirm the propagating feature of saltation in maintaining near-face aeolian sand ***,the acceleration of saltating sand grains was obtained directly from the reconstructed trajectory,and the results reveal that the climbing stage of the saltating trajectory represents an critical process of energy transfer while the sand grains travel through air.

关键词： high-speed digital camera sand saltation particle tracking kinetic parameters

Effect of surface dissolution on kinetic parameters in flotation of ilmenite from different gangue minerals

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Transactions of Nonferrous Metals Society of China 2019年第12期29卷 2615-2626页

作者： Omid SALMANI NURI Mehdi IRANNAJAD Akbar MEHDILO Department of Mining and Metallurgical Engineering Amirkabir University of TechnologyTehranIran Department of Engineering University of Mohaghegh ArdabiliArdabiliIran

The effects of acid surface dissolution on the flotation kinetics of ilmenite(IL)and its common accompanied gangue minerals including olivine-pyroxene(Ol-Px),tremolite-clinochlore(Tr-Cch)and quartz were *** results show that through the surface dissolution the adsorption rate constant for ilmenite increases from 5.272 to 8.441 mol/(g·min)while it decreases for Ol-Px,Tr-Cch and quartz from 6.332,7.309 and 7.774 mol/(g·min)to 5.034,6.223 and 7.371 mol/(g·min),***,the flotation experiments on a binary mixture of minerals indicate that after surface dissolution the values of modified rate constant for ilmenite flotation from Ol-Px,Tr-Cch and quartz are enhanced from 36.15,36.52 and 47.86 min-1 to 41.72,45.78 and 56.24 min-1,*** results in the improvement of kinetic selectivity index(SI)in the separation of treated ilmenite from gangue *** evidenced by ICP-MS analysis,the decrease of kinetic parameters for gangue minerals can be due to the removal of Fe^2+,Ca^2+and Mg^2+ions from their surfaces,which results in the lack of enough active sites to interact with collector *** confirmed by contact angle measurements,this prevents the formation of a stable hydrophobic layer on the minerals surfaces for creating stable attachments between minerals and ***,the improvement of ilmenite flotation kinetics has a negative correlation with the iron content in its accompanied gangue minerals.

关键词： surface dissolution flotation kinetic parameters modified rate constant selectivity index collector adsorption

Removal characteristics and kinetic analysis of an aerobic vapor-phase bioreactor for hydrophobic alpha-pinene

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Journal of Environmental Sciences 2012年第8期24卷 1439-1448页

作者： Yifeng Jiang Shanshan Li Zhuowei Cheng Runye Zhu Jianmeng Chen College of Biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China Engineering Research Center of the Ministry of Education for Bioconversion and Biopurification Zhefiang University of Technology Hangzhou 310032 China

Biofiltration is considered an effective method to control volatile organic compounds （VOCs） pollution. This study was conducted to evaluate the potential use of a bacterial biofilter packed with wood chips and peat for the removal of hydrophobic α-pinene. When inoculated with two pure degraders and adapted activated sludge, a removal efficiency （RE） of more than 95% was achieved after a start- up period of 11 days. The maximum elimination capacity （EC） of 50 g/（m^***） with RE of 94% was obtained at empty bed retention time （EBRT） of 102 sec. When higher α-pinene concentrations and shorter EBRTs were applied, the REs and ECs decreased significantly due to mass-transfer and biological reaction limitations. As deduced from the experimental results, approximately 74% of ct-pinene were completely mineralized by the consortiums and the biomass yield was 0.60 g biomass/g α-pinene. Sequence analysis of the selected bands excised from denaturing gradient gel electrophoresis revealed that the inoculated pure cultures could be present during the whole operation, and others were closely related to bacteria being able to degrade hydrocarbons. The kinetic results demonstrated that the whole biofiltration for α-pinene was diffusion-limit controlled owing to its hydrophobic characteristics. These findings indicated that this bacterial biofiltration is a promising technology for the remediation of hydrophobic industrial waste gases containing ct-pinene.

关键词： biofilters gaseous α-pinene removal characteristics microbial community kinetic parameters

kinetics process of Tb(Ⅲ)/Tb couple at liquid Zn electrode and thermodynamic properties of Tb-Zn alloys formation

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Science China Chemistry 2017年第6期60卷 813-821页

作者： LiXia Luo YaLan Liu Ning Liu Kui Liu JinWen Pang LiYong Yuan ZhiFang Chai WeiQun Shi Laboratory of Nuclear Energy Chemistry Institute of High Energy Physics Chinese Academy of Sciences Key Laboratory of Radiation Physics and Technology Ministry of Education Institute of Nuclear Science and Technology Sichuan University

Electrochemical properties of rare-earth elements in the LiCl-KCl eutectic are important for the pyrometallurgical recycling process of spent nuclear fuels. In this work, the electrochemical properties of Tb(Ⅲ)/Tb(0) couple were studied by the cyclic voltammetry(CV) at a liquid Zn pool electrode. The results showed that this electrochemical reaction is quasi-reversible with mixed reversible diffusion control and the charge transfer control. The diffusion coefficient of Tb(Ⅲ) was determined to be in the order of ~10.5 cm2 s.1. Moreover, kinetic parameters, such as the standard rate constants(ks) and charge transfer coefficient(α) for the electroreduction of Tb(Ⅲ) to Tb(0) at the liquid Zn electrode, were calculated by the Nicholson method at 873 K. Additionally, it was found that Tb-Zn intermetallic compounds were easily to be formed in the measurements. Hence, the reduction process of Tb(Ⅲ)/Tb(0) couple on the Zn-coated Mo electrode was also studied to obtain more information of the Tb-Zn intermetallic compounds. Electrochemical signals stemming from various intermetallic compounds associated with TbZn12, Tb2Zn17, Tb13Zn58, Tb3Zn11, TbZn3, TbZn2 and TbZn, were observed. The thermodynamic data were thereafter estimated by applying the emf method at 823–923 K. The standard formation Gibbs energies and the standard equilibrium constant of each Tb-Zn intermetallic compounds were also calculated. Finally, enthalpies and entropies of formation and the apparent standard potentials of various Tb-Zn intermetallic compounds were also obtained.

关键词： Tb liquid Zn electrode kinetic parameters thermodynamic properties molten salt

Luminescence and low temperature trap centers in mixed rare earth borate crystal

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Journal of Rare Earths 2018年第10期36卷 1024-1029页

作者： D.Joseph Danie Indra Raj Panday H.J.Kim Sunghwan Kim U.Fawad Department of Physics Kyungpook National University Department of Radiological Science Cheongju University Department of Physics Kohat University of Science and Technology

The single crystal of this compound has been grown from melt by using a conventional Czochralski technique. The temperature dependent luminescence spectra were measured using a 265 nm laser as an exciting source in the range of 10-300 K. The scintillation decay time profile was measured and found to have three components. The influence of the trap centers on the luminescence properties was studied by means of thermoluminescence（TL） glow peak analysis. Low temperature TL glow peaks were measured in the temperature range of 10-300 K at the heating rate of 0.1 K/s for X-ray irradiated sample. The TL glow peak consists of two dominant peaks at 88 and 109 K. Several glow peaks with a complex nature causes the decrease in the light yield at temperatures below 250 K, and along with long scintillation decay components were observed. The trap parameters such as activation energy（E）, frequency factor（s）and order of kinetics（b） were calculated using various standard methods such as peak shape（PS）,variable heating rate（VHR）, initial rise（IR） and computerized glow curve deconvolution（CGCD）.

关键词： Rare earth Decay time Thermoluminescence kinetic parameters

Multi-time scale identification of key kinetic processes for lithium-ion batteries considering variable characteristic frequency

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Journal of Energy Chemistry 2023年第7期82卷 521-536,I0011页

作者： Haotian Shi Shunli Wang Jianhong Liang Paul Takyi-Aninakwa Xiao Yang Carlos Fernandez Liping Wang School of Information Engineering Southwest University of Science and TechnologyMianyang 621010SichuanChina Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China School of Pharmacy and Life Sciences Robert Gordon UniversityAberdeen AB10-7GJUK

The electrification of vehicles puts forward higher requirements for the power management efficiency of integrated battery management systems as the primary or sole energy *** this paper,an efficient adaptive multi-time scale identification strategy is proposed to achieve high-fidelity modeling of complex kinetic processes inside the *** specifically,a second-order equivalent circuit model network considering variable characteristic frequency is constructed based on the high-frequency,medium-high-frequency,and low-frequency characteristics of the key kinetic ***,two coupled sub-filters are developed based on forgetting factor recursive least squares and extended Kalman filtering methods and decoupled by the corresponding time-scale *** coupled iterative calculation of the two sub-filter modules at different time scales is realized by the voltage response of the kinetic diffusion *** addition,the driver of the low-frequency subalgorithm with the state of charge variation amount as the kernel is designed to realize the adaptive identification of the kinetic diffusion process ***,the concept of dynamical parameter entropy is introduced and advocated to verify the physical meaning of the kinetic *** experimental results under three operating conditions show that the mean absolute error and root-mean-square error metrics of the proposed strategy for voltage tracking can be limited to 13 and 16 mV,***,from the entropy calculation results,the proposed method can reduce the dispersion of parameter identification results by a maximum of 40.72%and 70.05%,respectively,compared with the traditional fixed characteristic frequency *** proposed method paves the way for the subsequent development of adaptive state estimators and efficient embedded applications.

关键词： Lithium-ion battery kinetic parameters Entropy evaluation Parameter identification Frequency characteristic