Study on Kinetic Characteristics of Alliinase

[Objective] The kinetic characteristics of alliinase was studied to select the optimum reaction performance. [Method] Alliinase activity was measured to analysis the influence of temperature, pH, substrate concentration and metal iron. [Result] Alliinase was an enzyme with thermal instability. Its optimum reaction temperature was 29℃ and pH value was 6.1. The Vmax was 0. 439 IU/mg and Km was 0.483 mmol/L by using natural extract as substrate. Alliinase activity was activated when the K^＋ , Mg^2＋ , Na^＋ and Cd^2＋ existed and alliinase activity was inhibited when Cu^2＋ existed. [Condusion] Results showed that the kinetic characteristics of alliinase supply the academic foundation for development and application of garlic medical products.

Hydrocarbon Generation Kinetic Characteristics from Different Types of Organic Matter

In order to contrast the hydrocarbon generation kinetic characteristics from different types of organic matter（OM）,18 samples from different basins were pyrolyzed using Rock-Eval-Ⅱapparatus under the open system.From the experimental results,the curve of hydrocarbon generation rate vs.temperature can be easily obtained,which usually can be used to optimize kinetic parameters （A,E,F）of the hydrocarbon generation model.In this paper,the parallel first-order reaction with a single frequency factor model is selected to describe the hydrocarbon generation kinetic characteristics. The hydrocarbon generation kinetic parameters reveal that the types of compound structures and chemical bonds of the lacustrine fades typeⅠOM are relatively homogeneous,with one dominating activation energy.The types of chemical bonds of the lacustrine facies typeⅡ2 OM and the terrestrial facies typeⅢOM are relative complex,with a broad activation energy distribution,and the reaction fraction of the preponderant activation energy drops with the decrease of hydrogen index.The impact of the activation energy distribution spaces on the geological extrapolation of kinetic parameters is also investigated.The results show that it has little effect on the hydrocarbon transformation ratio（TR）and therefore,the parallel first-order reaction model with proper number of activation energies can be better used to describe the hydrocarbon generation process.The geological extrapolation results of 18 samples of kinetic parameters show that the distribution range of the hydrocarbon generation rate of the typeⅠOM is relatively narrow and the hydrocarbon generation curve is smooth.In comparison,the distribution range of the hydrocarbon generation for typeⅢand typeⅡ2-ⅢOM are quite wide,and the hydrocarbon generation curves have fluctuation phenomena.The distribution range of the hydrocarbon generation rate and the fluctuation phenomena are related to the kinetic parameters of OM;the narrower the activation energy distribution,the narrower the hydrocarbon generation rate distribution,and the smoother the hydrocarbon generation curve,and vice versa.

Kinetic characteristics of coal gas desorption based on the pulsating injection

In order to understand the kinetic characteristics of coal gas desorption based on the pulsating injection （PI）, the research experimentally studied the kinetic process of methane desorption in terms of the PI and hydrostatic injection （HI）. The results show that the kinetic curves of methane desorption based on PI and HI are consistent with each other, and the diffusion model can best describe the characteristics of meth- ane desorption. Initial velocity, diffusion capacity and ultimate desorption amount of methane desorption after P! are greater than those after HI, and the ultimate desorption amount increases by 16.7-39.7%. Methane decay rate over the time is less than that of the HI. The PI influences the diffusion model param- eters, and it makes the mass transfer Biot number B＇_i decrease and the mass transfer Fourier series F＇_0 increase. As a result, PI makes the methane diffusion resistance in the coal smaller, methane diffusion rate greater, mass transfer velocity faster and the disturbance range of methane concentration wider than HI. Therefore, the effect of methane desorption based on PI is better than that of HI.

Kinetic Characteristics in Pyrolysis of RPF with Additives

PVC（polyvinyl chloride） was isolated from waste plastic before manufacturing RPF（refuse paper ＆ plastic fuel）, and the characteristics of manufactured RPF including properties, calorific value, pyrolysis, chlorine content and kinetics analysis were analyzed. Based on the result of TGA（Thermogravimetric analysis）, the kinetics characteristics was analyzed by using Kissinger method and Ozawa method which are the most common methods for obtaining activation energy, and the experimental conditions of TGA were set as follows： in a nitrogen atmosphere, with gas flow rate of 20mL/min, heating rate of 5-50 ℃/min, and maximum temperature of 800 ℃. In conclusion, the activation energy showed a tendency to gradually increase by a rise of reaction rate. Although the activation energy with pyrolysis of RPF was irregularly scattered, it was shown that the activation energy was stabilized by co-pyrolysis of RPF and additives（rice bran and sawdust）.

Medium-low temperature hydrothermal hydrolysis kinetic characteristics of concentrated wet microalgae biomass

To improve microalgae biomass utilization efficiency during biofuel production process,medium-low temperature hydrothermal hydrolysis pretreatment was adopted in this study.The pretreatment kinetic characteristics of concentrated wet microalgae Chlorella vulgaris biomass(50 g/L)under medium-low temperature hydrolysis(100°C-200°C)were experimentally investigated.The hydrothermal hydrolysis kinetics describing the coupled effects of temperature,initial pressure and retention time then were proposed using response surface methodology(RSM).The maximum carbohydrate yield reached 327.3 mg/g dried biomass under initial pressure of 4 MPa at reaction temperature of 150°C for 120 min.The maximum protein yield(321.5 mg/g dried biomass)was obtained under initial pressure of 4 MPa at reaction temperature of 200°C for 60 min.Based on the hydrothermal hydrolysis kinetic models,it was confirmed that temperature was the most important factor affecting both carbohydrate and protein release during hydrothermal hydrolysis process.Hydrothermal initial pressure and retention time were significant to carbohydrate release,but not to protein release.While,lipid was mainly distributed in microalgae residual and almost did not exist in supernatant(about 8.03 mg/g).And with assistance of mixed hexane and methanol(the ratio of hexane to methanol was 7:3),67.69%of microalgae lipid was extracted out from hydrothermal hydrolysed microalgae residual(123.3 mg/g dried biomass).

DEBRIS FLOW KINETIC CHARACTERISTICS UNDER NATURAL CONDITIONS

The study for debris flow kinetic characteristics can not be approached by experiments due to their complexity and distransparency,etc.This paper is a picture of debris flow kinetic characteristics based on the natural debris flow observation and experiments.The kinetic characteristics of viscous debris flow are obtained by radar veloeimeter and ultrasonic level meter in jiangjia ravine.From those,the following are suggested:in natural channel, debris flow can be classified as three kinds of type:strong turbulent debris flow;turbulent debris flow;weak turbulent debris flow:meanwhile the Reynolds number(Re)is chosen as an index for the classification.

Combustion characteristics and kinetics of anthracite with added chlorine

The combustion process of Yangquan anthracite（YQ） with the addition of 0.045wt%, 0.211wt%, 1.026wt%, and 2.982wt% chlorine was investigated using a thermogravimetric method from an ambient temperature to 1173 K in an air atmosphere. Results show that the YQ combustion characteristics are not significantly affected by an increase in chlorine content. Data acquired for combustion conversion are then further processed for kinetic analysis. Average apparent activation energies determined using the model-free method（specifically the KAS method） are 103.025, 110.250, 99.906, and 110.641 k J/mol, respectively, and the optimal kinetic model for describing the combustion process of chlorine-containing YQ is the nucleation kinetic model, as determined by the z（α） master plot method. The mechanism function of the nucleation kinetic model is then employed to estimate the pre-exponential factor, by making use of the compensation effect. The kinetic models to describe chlorine-containing YQ combustion are thus obtained through advanced determination of the optimal mechanism function, average apparent activation energy, and the pre-exponential factor.

Pyrolysis Characteristics and Kinetics of Municipal Solid Waste

Based on a systemic survey, the pyrolysis characteristics and apparent kinetics of the municipal solid waste （ MSW） under different conditions were researched using a special pyrolysis reactor, which could overcome the disadvantage of thermo-gravimetric analyzer. The thermal decomposition behaviour of MSW was investigated using thermo-gravimetric （ TG ） analysis at rates of 4.8,6.6,8.4, 12.0 and 13. 2 K/min. The pyrolysis characteristics of MSW were also studied in different function districts. The pyrolysis of MSW is a complex reaction process and three main stages are found according to the results. The first stage represents the degradation of cellulose and hemicellulose, with the maximum degradation rate occuring at 150℃ -200 ℃： the second stage represents dehydrochlorination and depolymerization of intermediate products and the differential thermogravimetric （ DTG ） curves have shoulder peaks at about 300℃： the third stage is the decomposition of the residual big molecular organic substance and lignin at 400 ℃- 600 ℃. Within the range of given experimental conditions, the results of non-linear fitting algorithm and experiment are in agreement with each other and the correlation coefficients are over0. 99. The kinetic characteristics are concerned with the material component and heating rate. The activation energy of reaction decreases with the increase of heating rate.

Thermal decomposition characteristics and kinetics of methyl linoleate under nitrogen and oxygen atmospheres

The thermal decomposition characteristics of methyl linoleate （ML） under nitrogen and oxygen atmo- spheres were investigated, using a thermogravimetric analyzer at a heating rate of 10 ~C/min from room tem- perature to 600℃. Furthermore, the pyrolytic and kinetic characteristics of ML at different heating rates were stud- ied. The results showed that the thermal decomposition characteristics of ML under nitrogen and oxygen atmo- spheres were macroscopically similar, although ML exhibited relatively lower thermal stability under an oxy- gen atmosphere than under a nitrogen atmosphere. The initial decomposition temperature, the maximum weight loss temperature, the peak decomposition temperature, and the rate of maximum weight loss of ML under an oxygen atmosphere were much lower than those under a nitrogen atmosphere and increased with increasing heating rates under either oxygen or nitrogen atmosphere. In addition, the kinetic characteristics of thermal decomposition of ML were elucidated based on the experimental results and by the multiple linear regression method. The activation energy, pre-exponential factor, reaction order, and the kinetic equation for thermal decomposition of ML were obtained. The comparison of experimental and calculated data and the analysis of statistical errors of pyrolysis ratios demonstrated that the kinetic model was reliable for pyrolysis of ML with relative errors of about 1%. Finally, the kinetic compensation effect between the pre-exponential factors and the activation energy in the pyrolysis of ML was also confirmed.

The Kinetic Energy Budget and Circulation Characteristics of the Tropical Storm Irma during AMEX Phase Ⅱ

By using the data from observation on the Chinese research vessel Xiang Yang Hong No.5 and other sources during AMEX phase II, the kinetic energy budget and circulation characteristics of the tropical storm Irma were analyzed.Irma formed on the ITCZ of the Southern Hemisphere. During the formative stage of the storm, the SE trades and monsoon westerlies on both sides of the ITCZ strengthened, and more importantly, there was a strong divergent flow in upper troposphere. These contributed to the intensification of Irma. At the time when Irma formed, the Richardson number (Ri) in middle and lower troposphere was much smaller than that prior to and post the formation.When Irma intensified rapidly, the area-averaged kinetic energy in the general flow increased in the whole troposphere . The largest contribution came from kinetic energy generation term, -[v.(?)(?)] .indicates that there existed a strong ageostrophic accetration. As to the generation term , the conversion of available potential energy to kinetic energy, - |ωα|, made the largest contribution. This illustrates the importance of internal sources and of the ensemble effect of cumulus convection to the kinetic energy.To the increase of area-averaged eddy kinetic energy during the rapid intensification of Irma, the most impor tant source in the whole troposphere was the dissipation term - [E'], that should be interpreted as the. feeding of eddy kinetic energy from smaller to larger scale disturbances. Another important source was generation term, - [v' (?)(?)'], in the lower troposphere. Rather small contribution came from the energy conversion from the kinetic energy of area-mean flow to eddy kinetic energy. Therefore, the eddy kinetic energy of the developing tropical disturbance extracted both from smaller an, .arger scale motions. The former was much more important than the latter In addition, the disturbance acting as a generator and exporter, generated and exported eddy kinetic energy to the environmental atmosphere.

Kinetic Investigation of Ce,Y-CPAmA Systems and Simultaneous Determination of Sc,Y,Ce via Complementary Tristimulus Spectrophotometry

In the past ten years the eomplementary tristimulus speetrophotometryll],eTs,has seen its diverse appli-eations{2一61 though most researehes remain in relatively simpe systems,and less work has been involvinkinetie reaetions. An attemPt has been made on the investigation of some comPlieated systems eontainingrare earths and meta一acetylchloroPhosPhonaz

Kinetic characteristic for a synchronal rotary compressor

An angular speed,acceleration and tangential leakage of a synchronal rotary compressor in which both bladed rotor and a cylinder are discussed.The calculation formulae of revolving speed of cylinder and relative speed between the cylinder and bladed rotor are deduced detailedly in this paper.The variation of tangential speed and cylinder acceleration with angular position is investigated for a complete cycle.And some key parameters affected the relative speed are found out,viz,the relative speed depends on the radius of the cylinder and rotary speed of the axis,and the ratio of the cylinder to bladed rotor has not too much influence.It is the theoretic basis of designing and optimizing of structure characteristic of a synchronal rotary compressor.Also a computing formula of leakage related with rotary speed is deduced.It could supply references to thermodynamic calculating.

Alteration of glutathione S-transferase properties during the development of Micromelalopha troglodyta larvae (Lepidoptera: Notodontidae)

Micromelalopha troglodyta （Graeser） is an important pest of poplar in China. Glutathione S-transferases （GSTs） are known to be responsible for adaptation mechanisms of M. troglodyta. The activities and kinetic constants of glutathione S-transferases in M. troglodyta were studied. Significant differences in glutathione S-transferase activity and kinetic characteristics were observed among five instars of M. troglodyta larvae. Furthermore, the inhibition of glutathione S-transferase activity in five instars by 24 inhibitors was conducted. The results show the inhibition of GST activity of different instars by 24 inhibitors was different. For GST activity in the 1st instar, chlorpyrifos, lambda-cyhalothrin, endosulfan, abamectin, fipronil and pyridaben were the best inhibitors tested, and for GST activity in the 2nd instar, tannic acid and quercetin were the most potent inhibitors tested, and for GST activity in the 3rd instar, the inhibitory effects of quercetin, chlorpyrifos and lambda-cyhalothrin were the highest, and for GST activity in the 4th instar, quercetin and lambda-cyhalothrin were the best inhibitors, and the inhibitory effect of phoxim was the highest for GST activity in the 5th instar. Our results show that glutathione S-transferases in different instars are qualitatively different in isozyme composition and thus different in sensitivity to inhibitors.

Design of Synchronous Drive Mechanism of Opposed-Piston Hydraulic-Output Engine

In order to improve the thermal power conversion capacity of the internal combustion engine,combined with existing opposed-piston two-stroke engine（ OP2S） and hydraulic free piston engine（HFPE）,the integral structure for a newtype of opposed-piston hydraulic-output（ OPHO） engine has been designed,an operating principle has been introduced,the composition of its synchronous drive mechanism has been carefully analyzed,and a mathematical model has been built. In addition,the kinematics models of both the mechanism and the conventional crank-link mechanism have been established by utilizing MATLAB,and the movement rules of the pivotal moving components have been obtained. According to the simulation results,the piston movement of this newtype of opposed-piston hydraulic-output engine reveals a prominent asymmetry compared to the conventional crank-link engine. Under a fixed engine revolving speed,the compression time of the opposedpiston hydraulic-output engine is shortened while the expanding time is lengthened,thus the gas turbulence intensity is strengthened around the top dead center（ TDC） position. Meanwhile,the piston obtains a longer isometric process compared to conventional engines,which could be benefitial to enhance the combustion efficiency.

Low-temperature oxidation of light crude oil in oxygen-reduced air flooding

Light crude oil from the lower member of the Paleogene Xiaganchaigou Formation of Gaskule in Qinghai Oilfield was selected to carry out thermal kinetic analysis experiments and calculate the activation energy during the oil oxidation process.The oxidation process of crude oi l in porous medium was modeled by crude oil static oxidation experiment,and the component changes of crude oil before and after low-temperature oxidation were compared through Fourier transform ion cy-clotron resonance mass spectrometry and gas chromatography;the dynamic displacement experiment of oxygen-reduced air was combined with NMR technology to analyze the oil recovery degree of oxygen-reduced air flooding.The whole process of crude oil oxidation can be divided into four stages:light hydrocarbon volatilization,low-temperature oxidation,fuel deposition,and high temperature oxidation;the high temperature oxidation stage needs the highest activation energy,followed by the fuel deposition stage,and the low-temperature oxidation stage needs the lowest activation energy;the concentration of oxygen in the reaction is negatively correlated with the activation energy required for the reaction;the higher the oxygen concentration,the lower the average activation energy required for oxidation reaction is;the low-temperature oxidation reaction between crude oil and air generates a large amount of heat and CO,CO_(2) and CH4,forming flue gas drive in the reservoir,which has certain effects of mixing phases,reducing viscosity,lowering interfacial tension and promoting expansion of crude oil,and thus helps enhance the oil recovery rate.Under suitable reservoir temperature condition,the degree of recovery of oxygen-reduced air flooding is higher than that of nitrogen flooding for all scales of pore throat,and the air/oxygen-reduced air flooding de-velopment should be preferred.

Modeling and simulation of dynamic performance of horizontal steam-launch system

Based on theory of variable-mass system thermodynamics, the dynamic mathematic models of each component of the horizontal steam-launch system were established, and by the numerical simulation of the system launching process, the thermodynamics and kinetics characteristics of the system with three valves of different flow characteristics were got. The simulation results show that the values of the peak-to-average ratios of dimensionless acceleration with the equal percentage valve, the linear valve and the quick opening valve are 1.355, 1.614 and 1.722, respectively, and the final values of the dimensionless velocities are 0.843, 0.957 and 1.0, respectively. In conclusion, the value of the dimensionless velocity with the equal percentage valve doesn't reach the set value of 0.90 when the dimensionless displacement is 0.82, while the system with the linear valve can meet the launching requirement, as well as the fluctuation range of dimensionless acceleration is less than that of the quick opening valve. Therefore, the system with the linear valve has the best performance among the three kinds of valves.

Influences of molybdenum substitution for cobalt on the phase structure and electrochemical kinetic properties of AB_5-type hydrogen storage alloys

The effects of the partial replacement of Co with Mo on the phase structure and electrochemical kinetic properties of La0.35Ce0.65Ni3.54Co0.80-xMn0.35Al0.32Mox （x=0.00, 0.10, 0.15, 0.20, 0.25） hydrogen storage alloys prepared by arc-melting method were sys-tematically studied in this paper. The X-ray diffraction （XRD） showed that after partial substitution of Mo for Co, the alloys remained a single LaNi5 phase with a hexagonal CaCu5-type structure. The P-C isotherms indicated that the equilibrium pressure gradually decreased with in-creasing of Mo content. Electrochemical studies showed that the substitution of Mo for Co could greatly increase discharge capacity, improve activation ability and reduce self-discharge of alloy electrodes. The alloy with x=0.25 exhibited a higher rate dischargeability （HRD1200= 50.9%）. Moreover, Mo is a vital element in favor of kinetic properties of AB5-type hydrogen storage alloys. As Mo content increased, the ex-change current density I0, the hydrogen diffusion rate gradually increased.

Cu_(2)Se@C thin film with three-dimensional braided structure as a cathode material for enhanced Cu^(2+) storage

In the face of multiple challenges brought by the changes of global climate and environment,developing clean energy and updating green energy storage equipment are important ways to achieve carbon peak and carbon neutrality.Aqueous batteries have become a research hotspot due to their advantages of using the multivalent charge carrier,high ionic conductivity,environmental friendliness and cost effectiveness.In this work,the Cu_(2)Se@C(Cu_(2)Se coated on carbon clothes)thin film with a three-dimensional braided structure is fabricated by a simple electrochemical deposition method for Cu^(2+)storage for the first time.Compared with the commercial Cu_(2)Se powder,the well-designed Cu_(2)Se@C film shows enhanced specific capacity(640 mAh/g at 0.5 A/g)and rate performance(542 mAh/g at 5 A/g)as well as superior cycling stability(82.7%capacity retention after 1000 cycles at 1 A/g).The Cu^(2+)storage mechanism of the Cu_(2)Se@C electrode is based on a reversible phase transition process of Cu_(2)Se←→Cu_(2-x)Se←→CuSe←→CuSe_(2).In kinetic characteristic analysis,the Cu_(2)Se@C electrode demonstrates faster Cu^(2+)diffusion in discharge process than charge process resulting from the phase transition and the variation of interplanar spacing.This work highlights a facile one-piece design strategy and opens a new gateway for the exploration of advanced aqueous energy storage systems.