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An aqueous BiI_(3)-Zn battery with dual mechanisms of Zn^(2+)(de)intercalation and I^(-)/I_(2)redox
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作者 Qi Deng Fangzhong Liu +3 位作者 Xiongwei Wu Changzhu Li Weibin Zhou Bei Long 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期670-678,I0014,共10页
The development of aqueous battery with dual mechanisms is now arousing more and more interest.The dual mechanisms of Zn^(2+)(de)intercalation and I^(-)/I_(2)redox bring unexpected effects.Herein,differing from previo... The development of aqueous battery with dual mechanisms is now arousing more and more interest.The dual mechanisms of Zn^(2+)(de)intercalation and I^(-)/I_(2)redox bring unexpected effects.Herein,differing from previous studies using Zn I_(2)additive,this work designs an aqueous Bi I_(3)-Zn battery with selfsupplied I^(-).Ex situ tests reveal the conversion of Bi I_(3)into Bi(discharge)and Bi OI(charge)at the 1st cycle and the dissolved I^(-)in electrolyte.The active I^(-)species enhances the specific capacity and discharge medium voltage of electrode as well as improves the generation of Zn dendrite and by-product.Furthermore,the porous hard carbon is introduced to enhance the electronic/ionic conductivity and adsorb iodine species,proven by experimental and theoretical studies.Accordingly,the well-designed Bi I_(3)-Zn battery delivers a high reversible capacity of 182 m A h g^(-1)at 0.2 A g^(-1),an excellent rate capability with 88 m A h g^(-1)at 10 A g^(-1),and an impressive cyclability with 63%capacity retention over 20 K cycles at 10 A g^(-1).An excellent electrochemical performance is obtained even at a high mass loading of 6 mg cm^(-2).Moreover,a flexible quasi-solid-state Bi I_(3)-Zn battery exhibits satisfactory battery performances.This work provides a new idea for designing high-performance aqueous battery with dual mechanisms. 展开更多
关键词 Aqueous BiI_(3)-Zn battery Dual mechanisms I^(-)-induced uniform zinc deposition Ultralong cyclic life Flexible quasi-solid-state battery
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Inhibitory Effect of Flavonoid Glycosides from Chlorophytum comosum on Nasopharyngeal Carcinoma 5-8F Cells and Its Mechanism
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作者 Chenliang CHU Xinchen WANG +2 位作者 Kuan LU Liang QIN Lu JIN 《Medicinal Plant》 2024年第1期66-70,共5页
[Objectives]To study the inhibitory activity of two flavonoid glycosides isolated from Chlorophytum comosum Laxum R.Br on human nasopharyngeal carcinoma(NPC)cell line 5-8F in vitro and its mechanism.[Methods]The flavo... [Objectives]To study the inhibitory activity of two flavonoid glycosides isolated from Chlorophytum comosum Laxum R.Br on human nasopharyngeal carcinoma(NPC)cell line 5-8F in vitro and its mechanism.[Methods]The flavonoid glycosides were isolated and purified from the ethanol alcoholic extract of the roots of Liliaceae plant Chlorophytum comosum by silica gel column chromatography,macroporous resin column chromatography,Sephadex LH-20,and reverse column chromatography(ODS).The inhibitory activity of flavonoid glycosides on human nasopharyngeal carcinoma cells was analyzed by CCK-8 method,and the potential mechanism was preliminarily analyzed by molecular docking.[Results]Two flavonoid glycosides were identified as isovitexin 2″-0-rhamnoside and 7-2″-di-O-β-glucopyranosylisovitexin.Two flavonoid glycosides showed promising inhibitory effect on human nasopharyngeal carcinoma cell line 5-8F,with IC_(50) values of 24.8 and 27.5μmol/L,respectively.Molecular docking results showed that the potential targets of two flavonoid glycosides include CyclinD1,Bcl-2β-Catenin,ILK,TGF-β,in addition,two glycosides showed higher predicted binding affinity towards CyclinD1,which verifies the cytotoxicity of the two compounds on human nasopharyngeal carcinoma cell line 5-8F in vitro.[Conclusions]Two flavonoid glycosides are the active molecules in Chlorophytum comosum that can inhibit the proliferation of human nasopharyngeal carcinoma cells,and have the potential to be used in the research and development of anti nasopharyngeal carcinoma drugs. 展开更多
关键词 Chlorophytum comosum Laxum R.Br. Flavonoid glycosides 5-8F cells Antitumor mechanism
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Influence of Non-Natural Ageing Temperature on the Microstructural Characteristics and Mechanical Properties of Cast Aluminum 6063 Alloy
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作者 Oluwole Oladele Ayodele Adedeke +1 位作者 Olajesu Olanrewaju Samuel Olusunle 《Journal of Minerals and Materials Characterization and Engineering》 2024年第2期91-99,共9页
This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and ... This research considered the effect of non-natural aging on the microstructural characteristics and mechanical properties of as-cast aluminum 6063 alloys. The samples were developed through a sand casting process and machined into tensile and impact test samples before carrying out solution heat treatment at 550?C (0.83 T<sub>m</sub>) on two parts of the samples while retaining one part as the control. The two parts were further divided into sets denoted A and B and were aged at 180?C (0.27 T<sub>m</sub>) and 160?C (0.24 T<sub>m</sub>), respectively, for 12 hours. The results showed that sample A has the optimal yield strength and ultimate tensile strength of 192 and 206 MPa, respectively. Likewise, the sample gave the highest impact strength value of about 9.63 J/mm<sup>2</sup>. The observed results were supported by the optical micrograph, which revealed that the sample has evenly dispersed precipitates in its microstructure. This is deemed responsible for the observed increase in strength of the sample. 展开更多
关键词 Aluminum Alloy non-Natural Ageing mechanical Properties Microstructural Features
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Characteristics of Emission Non-nulling Pulsars Through Simulation
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作者 Rai Yuen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期91-102,共12页
We investigate the population and several properties of radio pulsars whose emission does not null(non-nulling)through simulation of a large pulsar sample.Emission from a pulsar is identified as non-nulling if(i)the e... We investigate the population and several properties of radio pulsars whose emission does not null(non-nulling)through simulation of a large pulsar sample.Emission from a pulsar is identified as non-nulling if(i)the emission does not cease across the whole pulse profile,and(ii)the emission is detectable.For(i),we adopt a model for switching in the plasma charge density,and emission persists if the charge density is non-zero.For(ii),we assume that detectable emission originates from source points where it is emitted tangentially to the magnetic field-line and parallel to the line-of-sight.We find that pulsars exhibiting non-nulling emission possess obliquity angles with an average of 42°.5,and almost half the samples maintain a duty cycle between 0.05 and 0.2.Furthermore,the pulsar population is not fixed but dependent on the obliquity angle,with the population peaking at 20°.In addition,three evolutionary phases are identified in the pulsar population as the obliquity angle evolves,with the majority of samples having an obliquity angle between 20°and 65°.Our results also suggest that emission from a pulsar may evolve between nulling and non-nulling during its lifetime. 展开更多
关键词 radiation mechanisms:non THERMAL stars:neutron (stars:)pulsars:general
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Non-isothermal Decomposition Mechanism and Kinetics of LiClO_4 in Nitrogen 被引量:3
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作者 DIAKITE Kahirou 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第2期300-303,共4页
The non-isothermal decomposition kinetics of LiClO4 in flow N2 atmosphere was studied. TG-DTA curves show that the decomposition proceeded through two well-defined steps below 900℃, and the mass loss was in agreement... The non-isothermal decomposition kinetics of LiClO4 in flow N2 atmosphere was studied. TG-DTA curves show that the decomposition proceeded through two well-defined steps below 900℃, and the mass loss was in agreement with the theoretical value. XRD profile demonstrates that the product of the thermal decomposition at 500℃ is LiCI. For the decomposition kinetics study, the activation energies calculated with the Friedman method were considered as the initial values for non-linear regression and were used for verifying the correctness of the fired models. The decomposition process was fitted by a two-step consecutive reaction: extended Prout-Tompkins equation[Bna, f(α) is (1-α)^nα^α] followed by a lth order reaction(F1). The activation energies were (215.6±0.2) and (251.6±3.6) kJ/mol, respectively. The exponentials n and a for Bna reaction were (0.25±0.05) and (0.795±0.005), respectively. The reaction types and activation energies were in agreement with those obtained from the isothermal method, but the exponentials were optimized for better firing and prediction. 展开更多
关键词 LICLO4 Decomposition mechanism non-isothermal kinetics non-linear regression
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The Mechanism of Drag Reduction around Bodies of Revolution Using Bionic Non-Smooth Surfaces 被引量:16
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作者 Li-mei Tian Lu-quan Ren +2 位作者 Qing-ping Liu Zhi-wu Han Xiao Jiang 《Journal of Bionic Engineering》 SCIE EI CSCD 2007年第2期109-116,共8页
Bionic non-smooth surfaces (BNSS) can reduce drag. Much attention has been paid to the mechanism of shear stress reduction by riblets. The mechanism of pressure force reduction by bionic non-smooth surfaces on bodie... Bionic non-smooth surfaces (BNSS) can reduce drag. Much attention has been paid to the mechanism of shear stress reduction by riblets. The mechanism of pressure force reduction by bionic non-smooth surfaces on bodies of revolution has not been well investigated. In this work CFD simulation has revealed the mechanism of drag reduction by BNSS, which may work in three ways. First, BNSS on bodies of revolution may lower the surface velocity of the medium, which prevents the sudden speed up of air on the cross section. So the bottom pressure of the model would not be disturbed sharply, resulting in less energy loss and drag reduction. Second, the magnitude of vorticity induced by the bionic model becomes smaller because, due to the sculpturing, the growth of tiny air bubbles is avoided. Thus the large moment of inertia induced by large air bubble is reduced. The reduction of the vorticity could reduce the dissipation of the eddy. So the pressure force could also be reduced. Third, the thickness of the momentum layer on the model becomes less which, according to the relationship between the drag coefficient and the momentum thickness, reduces drag. 展开更多
关键词 bionic non-smooth surface drag reduction mechanisms boundary layer pressure force
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Design and Experimental Research on Seedling Pick-Up Mechanism of Planetary Gear Train with Combined Non-circular Gear Transmission 被引量:11
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作者 Yaxin Yu Jikun Liu +4 位作者 Bingliang Ye Gaohong Yu Xuejun Jin Liang Sun Junhua Tong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第3期42-54,共13页
Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent ... Currently, transplanting mechanisms for dryland plug seedlings in China are mainly semiautomatic and have low efficiency. The rotary seedling pick-up mechanism with a planetary gear train for non-uniform intermittent transmission, and a concave and convex locking arc device, has a large rigid impact. To solve these problems, according to the design requirements for a dryland plug seedling transplanting mechanism, a rotary seedling pick-up mechanism of a planetary gear train with combined non-circular gear transmission of incomplete eccentric circular and noncircular gears was proposed. This has the characteristics of two-times greater fluctuation of the transmission ratio in a cycle, and can achieve a non-uniform continuous drive. Through analysis of the working principle of the seedling pick-up mechanism, its kinematics model was established. The human–computer interaction optimization method and self-developed computer-aided analysis and optimization software were used to obtain a set of parameters that satisfy the operation requirements of the seedling pick-up mechanism. According to the optimized parameters, the structure of the seedling pick-up mechanism was designed, a virtual prototype of the mechanism was created, and a physical prototype was manufactured. A virtual motion simulation of the mechanism was performed, high-speed photographic kinematics tests were conducted, and the kinematic properties of the physical prototype were investigated, whereby the correctness of the theoretical model and the optimized design of the mechanism were verified. Further, laboratory seedling pick-up tests were conducted. The success ratio of seedling pick-up was 93.8% when the seedling pick-up efficiency of the mechanism was 60 plants per minute per row, indicating that the mechanism has a high efficiency and success ratio for seedling pick-up and can be applied to a dryland plug seedling transplanter. 展开更多
关键词 Dryland plug SEEDLING transplanter Rotary SEEDLING PICK-UP mechanism TRANSMISSION ratio non-uniform continuous TRANSMISSION COMBINED non-CIRCULAR gear TRANSMISSION Optimization design
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Kinematic Modeling and Characteristic Analysis of Eccentric Conjugate Non-circular Gear & Crank-Rocker & Gears Train Weft Insertion Mechanism 被引量:8
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作者 陈建能 赵华成 +2 位作者 王英 徐高欢 周鸣 《Journal of Donghua University(English Edition)》 EI CAS 2013年第1期15-20,共6页
A novel weft insertion mechanism named eccentric conjugate non-circular gear & crank-rocker & gears train weft insertion mechanism was proposed in order to better meet the requirements of rapier loom's wef... A novel weft insertion mechanism named eccentric conjugate non-circular gear & crank-rocker & gears train weft insertion mechanism was proposed in order to better meet the requirements of rapier loom's weft insertion mechanism as well as reduce the manufacturing difficulty. Meanwhile, based on the working principle of this mechanism, kinematical mathematic models of this mechanism were established and an aided analysis and simulation software was compiled. The influences of eccentricity ratio, deformation coefficient, and other important parameters on the kinematics characteristics of this mechanism were analyzed by using the software. A group of preferable parameters which could meet the requirements of weft insertion technology were obtained by means of human-computer interactive optimization method. The maximum velocity, maximum acceleration, and variation of acceleration of this mechanism are smaller than those of the conjugate cam weft insertion mechanism applied on TT96 rapier loom under the conditions of the same unilateral total stroke of rapier head and the same rotary speed of loom spindle; meanwhile the other demands of weaving technology can be met by this novel weft insertion mechanism. 展开更多
关键词 weft insertion mechanism eccentric conjugate non-circular gear crank-rocker kinematics
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Design of a Non-cooperative Target Capture Mechanism 被引量:2
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作者 WANG Chen NIE Hong +1 位作者 CHEN Jinbao PAN Zhengwei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第1期146-153,共8页
A passive compliant non-cooperative target capture mechanism is designed to maintain the non-cooperative target on-orbit. When the relative position between capture mechanism and satellite is confirmed,a pair of four-... A passive compliant non-cooperative target capture mechanism is designed to maintain the non-cooperative target on-orbit. When the relative position between capture mechanism and satellite is confirmed,a pair of four-bar linkages lock the docking ring,which is used for connecting the satellite and the rocket. The mathematical model of capture mechanism and capture space is built by the Denavit-Hartenberg(D-H)method,and the torque of each joint is analyzed by the Lagrange dynamic equation. Besides,the capture condition and the torque of every joint under different capture conditions are analyzed by simulation in MSC. Adams. The results indicate that the mechanism can capture the non-cooperative target satellite in a wide range. During the process of capture,the passive compliant mechanism at the bottom can increase capture space,thereby reducing the difficulty and enhance stability of the capture. 展开更多
关键词 non-COOPERATIVE target passive COMPLIANCE CAPTURE mechanism KINEMATICS ANALYSIS dynamics ANALYSIS
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Molecular signaling mechanisms of apoptosis in hereditary non-polyposis colorectal cancer 被引量:7
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作者 Samar Hassen Nawab Ali Parimal Chowdhury 《World Journal of Gastrointestinal Pathophysiology》 CAS 2012年第3期71-79,共9页
Colorectal cancer is the second most leading cause of cancer related deaths in the western countries. One of the forms of colorectal cancer is hereditary non-polyposis colorectal cancer (HNPCC), also known as "Ly... Colorectal cancer is the second most leading cause of cancer related deaths in the western countries. One of the forms of colorectal cancer is hereditary non-polyposis colorectal cancer (HNPCC), also known as "Lynch syndrome". It is the most common hereditary form of cancer accounting for 5%-10% of all colon cancers. HNPCC is a dominant autosomal genetic disorder caused by germ line mutations in mismatch repair genes. Human mismatch repair genes play a crucial role in genetic stability of DNA, the inactivation of which results in an increased rate of mutation and often a loss of mismatch repair function. Recent studies have shown that certain mismatch repair genes are involved in the regulation of key cellular processes including apoptosis. Thus, differential expression of mismatch repair genes particularly the contributions of MLH1 and MSH2 play important roles in therapeutic resistance to certain cytotoxic drugs such as cisplatin that is used normally as chemoprevention. An understanding of the role of mismatch repair genes in molecular signaling mechanism of apoptosis and its involvement in HNPCC needs attention for further work into this important area of cancer research, and this review article is intended to accomplish that goal of linkage of apoptosis with HNPCC. The current review was not intended to provide a comprehensive enumeration of the entire body of literature in the area of HNPCC or mismatch repair system or apoptosis; it is rather intended to focus primarily on the current state of knowledge of the role of mismatch repair proteins in molecular signaling mechanism of apoptosis as it relates to understanding of HNPCC. 展开更多
关键词 COLORECTAL CANCER HEREDITARY non-polyposis COLORECTAL CANCER APOPTOSIS Molecular signaling mechanismS DNA mismatch repair proteins
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A Mixed-control Mechanism Model of Proeutectoid Ferrite Growth under Non-equilibrium Interface Condition in Fe-C Alloys 被引量:1
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作者 RuihengWU XueyuRUAN +1 位作者 HongbingZHANG T.Y.Hsu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第5期561-566,共6页
By combining the α/γ interface migration and the carbon diffusion at the interface in Fe-C alloys, a mathematical model is constructed to describe the mixed-control mechanism for proeutectoid ferrite formation from ... By combining the α/γ interface migration and the carbon diffusion at the interface in Fe-C alloys, a mathematical model is constructed to describe the mixed-control mechanism for proeutectoid ferrite formation from austenite. In this model, the α/γ interface is treated as non-equilibrium interface, i.e., the carbon concentration of austenite at γ/α interface is obtained through theoretical calculation, instead of that assumed as the local equilibrium concentration. For isothermal precipitation of ferrite in Fe-C alloys, the calculated results show that the rate of interface migration decreases monotonically during the whole process, while the rate of carbon diffusion from γ/α interface into austenite increases to a peak value and then decreases. The process of ferrite growth may be considered as composed of three stages: the period of rapid growth, slow growth and finishing stage. The results also show that the carbon concentration of austenite at γ/α interface could not reach the thermodynamic equilibrium value even at the last stage of ferrite growth. 展开更多
关键词 Proeutectoid ferrite precipitation non-equilibrium interface Phase transformation kinetics Mixed-control mechanism
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Design and Experiment of Non-circular Combined Gear Train Beating-up Mechanism 被引量:1
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作者 CHEN Jianneng YU Chennan +3 位作者 TONG Lin WANG Ying XIA Xudong ZHAO Xiong 《Journal of Donghua University(English Edition)》 EI CAS 2019年第1期8-14,共7页
The most important performance of a beating-up mechanism is that the dwelling time of the sley must ensure the completion of the weft insertion. To meet this requirement, a new non-circular combined gear train beating... The most important performance of a beating-up mechanism is that the dwelling time of the sley must ensure the completion of the weft insertion. To meet this requirement, a new non-circular combined gear train beating-up mechanism which is composed of two-stage planetary gear trains is proposed. The first-stage is a Fourier planetary gear train and the second-stage is a non-circular planetary gear train. For designing of this new mechanism, the ideal kinematic equations of the sley are constructed first. Then the kinematic model of the first-stage Fourier planetary gear train is established and the reverse solution for the pitch curves of the second-stage non-circular gears is deduced. With a computer-aided design program, the influences of several important parameters on the pitch curves of the second-stage non-circular gears are analyzed, and a set of preferable structural parameters are obtained. Finally, a test bed of this mechanism is developed and the experimental results show that this new beating-up mechanism can achieve the designed dwelling time, namely it can meet the requirements of beating-up process. 展开更多
关键词 beating-up mechanism FOURIER GEAR non-CIRCULAR GEAR PLANETARY GEAR train KINEMATIC
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Liquid-liquid Extraction System Based on Non-ionic Surfactant-salt-H_2O and Mechanism of Drug Extraction 被引量:3
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作者 LeiLI FengLIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期349-350,共2页
Extraction behavior of chlorpromazine hydrochloride (CPZ) and procaine hydro- chloride (PCN) in the system described in the title was studied. Research shows that the extraction efficiency of CPZ can amount to 96% by... Extraction behavior of chlorpromazine hydrochloride (CPZ) and procaine hydro- chloride (PCN) in the system described in the title was studied. Research shows that the extraction efficiency of CPZ can amount to 96% by twice extraction, while that of PCN is 77%. This system produces the distribution coefficients (KD) of 12.3 and 2.6 respectively for CPZ and PCN. Extraction mechanism is deduced according to ultraviolet and molecular fluorescence spectra variation of the drugs in the system studied. 展开更多
关键词 non-ionic surfactant-salt-H2O extraction system polyethylene glycol-1000 chlor- promazine hydrochloride procaine hydrochloride mechanism of extraction.
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Thermal decomposition mechanism and non-isothermal kinetics of the polyoxometalate of ciprofloxacin with 12-tungstoboric acid 被引量:1
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作者 WANGDunjia FANGZhengdong HANDeyan 《Rare Metals》 SCIE EI CAS CSCD 2005年第1期15-21,共7页
The polyoxometalate complex (CPFX-HCl)(4)H5BW12O40-12H(2)O was prepared in aqueous solution for the first time, and characterized by elemental analysis, IR spectrum, and TG-DTG. The TG-DTG curves showed that its therm... The polyoxometalate complex (CPFX-HCl)(4)H5BW12O40-12H(2)O was prepared in aqueous solution for the first time, and characterized by elemental analysis, IR spectrum, and TG-DTG. The TG-DTG curves showed that its thermal decomposition was a four-step process consisting of the simultaneous collapse of Keggin anion. The intermediate and residue of the decomposition were identified by mean of TG-DTG, IR, and XRD technique. The non-isothermal kinetic data were analyzed by the Achar method and Coats-Redfern method. The apparent activation energy (E) and the pre-exponential factor (In A) of each decomposition were obtained. The most probable thermal decomposition reaction mechanisms were proposed by comparison of the kinetic parameters. The kinetic equation for both the second stage and the third stage can be expressed as d alpha/dt = Ae(-E/RT) -(1 - alpha)(2), and the fourth stage d alpha/dt = Ae(-E/RT) -(1 - alpha). And their mathematic expressions of the kinetic compensation effects of thermal decomposition reaction were also determined. 展开更多
关键词 physical chemistry thermal decomposition mechanism non-isothermal kinetics TG-DTG polyoxometalate complex CIPROFLOXACIN tungstoborate
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Approximate Solution of Non-Linear Reaction Diffusion Equations in Homogeneous Processes Coupled to Electrode Reactions for CE Mechanism at a Spherical Electrode 被引量:2
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作者 A. Eswari S. Usha L. Rajendran 《American Journal of Analytical Chemistry》 2011年第2期93-103,共11页
A mathematical model of CE reaction schemes under first or pseudo-first order conditions with different diffusion coefficients at a spherical electrode under non-steady-state conditions is described. The model is base... A mathematical model of CE reaction schemes under first or pseudo-first order conditions with different diffusion coefficients at a spherical electrode under non-steady-state conditions is described. The model is based on non-stationary diffusion equation containing a non-linear reaction term. This paper presents the complex numerical method (Homotopy perturbation method) to solve the system of non-linear differential equation that describes the homogeneous processes coupled to electrode reaction. In this paper the approximate analytical expressions of the non-steady-state concentrations and current at spherical electrodes for homogeneous reactions mechanisms are derived for all values of the reaction diffusion parameters. These approximate results are compared with the available analytical results and are found to be in good agreement. 展开更多
关键词 non-LINEAR Reaction/Diffusion Equation HOMOTOPY PERTURBATION Method CE mechanism Reduction of Order SPHERICAL ELECTRODES
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Kinetics and Mechanism of Exothermic First-stage Decomposition Reaction for 2,6-Dinitro-4,8- bis(2,2,2-trinitroethyl)-2,4,6,8-tetra- azabicyclo[3.3.1] nonane-3,7-dionel
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作者 HURong-zu YANGDe-suo +7 位作者 ZHAOFeng-qi CHENPei LUOYang CHENSan-ping ZHAOHong-an SONGJi-rong GAOSheng-li SHIQi-zhen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期821-825,共5页
关键词 Decomposition 2 6-Dinitro-4 8- bis(2 2 2 -trinitroethyl)-2 4 6 8-tetraazabicyclo [3.3.1] nonane-3 7-dionel DSC Kinetics mechanism TG
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Observation of nonconservation characteristics of radio frequency noise mechanism of 40-nm n-MOSFET 被引量:1
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作者 王军 彭小梅 +3 位作者 刘志军 王林 罗震 王丹丹 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期527-532,共6页
Bias non-conservation characteristics of radio-frequency noise mechanism of 40-nm n-MOSFET are observed by modeling and measuring its drain current noise. A compact model for the drain current noise of 40-nm MOSFET is... Bias non-conservation characteristics of radio-frequency noise mechanism of 40-nm n-MOSFET are observed by modeling and measuring its drain current noise. A compact model for the drain current noise of 40-nm MOSFET is proposed through the noise analysis. This model fully describes three kinds of main physical sources that determine the noise mechanism of 40-nm MOSFET, i.e., intrinsic drain current noise, thermal noise induced by the gate parasitic resistance, and coupling thermal noise induced by substrate parasitic effect. The accuracy of the proposed model is verified by noise measurements, and the intrinsic drain current noise is proved to be the suppressed shot noise, and with the decrease of the gate voltage, the suppressed degree gradually decreases until it vanishes. The most important findings of the bias non-conservative nature of noise mechanism of 40-nm n-MOSFET are as follows.(i) In the strong inversion region, the suppressed shot noise is weakly affected by the thermal noise of gate parasitic resistance. Therefore, one can empirically model the channel excess noise as being like the suppressed shot noise.(ii) In the middle inversion region, it is almost full of shot noise.(iii) In the weak inversion region, the thermal noise is strongly frequency-dependent, which is almost controlled by the capacitive coupling of substrate parasitic resistance. Measurement results over a wide temperature range demonstrate that the thermal noise of 40-nm n-MOSFET exists in a region from the weak to strong inversion, contrary to the predictions of suppressed shot noise model only suitable for the strong inversion and middle inversion region. These new findings of the noise mechanism of 40-nm n-MOSFET are very beneficial for its applications in ultra low-voltage and low-power RF, such as novel device electronic structure optimization, integrated circuit design and process technology evaluation. 展开更多
关键词 nanoscale MOSFET non-conservation characteristics noise mechanism radio frequency
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Zincate mechanism on cast Al-Si alloy in non-cyanide multi-metal zincate solutions 被引量:1
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作者 黄晓梅 李宁 +1 位作者 黎德育 蒋丽敏 《中国有色金属学会会刊:英文版》 EI CSCD 2006年第2期414-420,共7页
Arrhenius formula was applied to calculate the apparent activation energy of zincate reaction. The standard electrode potential of all the metal coordinating ions and the order of galvanic couple of different metals i... Arrhenius formula was applied to calculate the apparent activation energy of zincate reaction. The standard electrode potential of all the metal coordinating ions and the order of galvanic couple of different metals in zincate solution were also calculated. Electrochemical behavior of zincate process was studied by Tafel polarization curves, E—t curves, and electrochemical impedance spectroscopy(EIS). The results show that the apparent activation energy of zincate reaction in non-cyanide multi-metal zincate solution is smaller than that in simple zincate solution, and precipitation sequence of all the metals in zincate solution is Cu, Ni, Fe and Zn. Relationship between the potential at 30 s before zincate and coverage was attained according to the change of potential of zincate. EIS shows that inductive reactance is produced during zincate. 展开更多
关键词 AL-SI合金 铸造 铝合金 锌酸盐 表观活化能
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Theoretical Study on the Reaction Mechanism of 2-Methoxybenzaldehyde,4-Bromo-indanone,Malononitrile and Ammonium Acetate One-pot to Form 6-(2-Methoxyphenyl)-2-amino-6-bromo-5H-indeno[1,2-b]pyridine-3-carbonitrile
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作者 张福兰 黄辉胜 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第10期1685-1696,共12页
The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-(2-methoxyphenyl)-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by densit... The reaction mechanism of 2-methoxybenzaldehyde, 4-bromo-indanone, malononitrile and ammonium acetate one-pot to form 6-(2-methoxyphenyl)-2-amino-6-bromo-5 Hindeno[1,2-b]pyridine-3-carbonitrile was studied by density functional theory. The geometries of the reactants, transition states, intermediates and products were optimized at the PW91/DNP level. Vibration analysis was carried out to confirm the transition state structure. Reaction pathways were investigated in this study. The result indicates that the reaction Re→ TSB1→IMB1→ TSB2→ IMB2→TSB3→IMB3→TSB4→IMB4→TSB5→IMB5→TSB6→IMB6→TSB7→IMB7→ TSB8→IMB8→TSB9→IMB9→P2 is the main pathway, the activation energy of which is the lowest. The dominant product predicted theoretically is in agreement with the experiment results. 展开更多
关键词 2-methoxybenzaldehyde 4-bromo-indanone 6-(2-methoxyphenyl)-2-amino-6-bromo-5H-indeno[1 2-b]pyridine-3-carbonitrile density functional reaction mechanism
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Decomposition mechanisms and non-isothermal kinetics of LiHC_2O_4·H_2O
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作者 CHOU Kuo-Chih 《Rare Metals》 SCIE EI CAS CSCD 2012年第6期615-620,共6页
The thermal decomposition process of LiHC2O4·H2O from 30 to 600 ℃ was investigated by the thermogravimetric and differential scanning calorimetry (TG-DSC). The phases decomposited at different temperature were c... The thermal decomposition process of LiHC2O4·H2O from 30 to 600 ℃ was investigated by the thermogravimetric and differential scanning calorimetry (TG-DSC). The phases decomposited at different temperature were characterized by X-ray diffraction (XRD), which indicated the decompositions at 150, 170, and 420℃, relating to LiHC2O4, Li2C2O4, Li2C2O4, and Li2CO3, respectively. Reaction mechanisms in the whole sintering process were determined, and the model fitting kinetic approaches were applied to data for non-isothermal thermal decomposition of LiHC2O4?H2O; finally, the kinetic parameters of each reaction were also calculated herein. 展开更多
关键词 apparent activation energy non-ISOTHERMAL reaction mechanism thermal decomposition
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