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A dendritic Cu/Cu_(2)O structure with high curvature enables rapid and efficient reduction of carbon dioxide to C_(2) in an H-cell
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作者 Lei shao Bochen Hu +3 位作者 Jinhui Hao Junjie Jin Weidong Shi Min Chen 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期144-153,共10页
Electrocatalytic reduction of CO_(2)(CO_(2)RR)to multicarbon products is an efficient approach for ad-dressing the energy crisis and achieving carbon neutrality.In H-cells,achieving high-current C_(2)products is chall... Electrocatalytic reduction of CO_(2)(CO_(2)RR)to multicarbon products is an efficient approach for ad-dressing the energy crisis and achieving carbon neutrality.In H-cells,achieving high-current C_(2)products is challenging because of the inefficient mass transfer of the catalyst and the presence of the hydrogen evolution reaction(HER).In this study,dendritic Cu/Cu_(2)O with abundant Cu^(0)/Cu^(+)interfaces and numerous dendritic curves was synthesized in a CO_(2)atmosphere,resulting in the high selectivity and current density of the C_(2)products.Dendritic Cu/Cu_(2)O achieved a C_(2)Faradaic efficiency of 69.8%and a C_(2)partial current density of 129.5 mA cm^(-2)in an H-cell.Finite element simulations showed that a dendritic structure with a high curvature generates a strong electric field,leading to a localized CO_(2)concentration.Additionally,DRT analysis showed that a dendritic struc-ture with a high curvature actively adsorbed the surrounding high concentration of CO_(2),enhancing the mass transfer rate and achieving a high current density.During the experiment,the impact of the electronic structure on the performance of the catalyst was investigated by varying the atomic ratio of Cu^(0)/Cu^(+) on the catalyst surface,which resulted in improved ethylene selectivity.Under the optimal atomic ratio of Cu^(0)/Cu^(+),the charge transfer resistance was minimized,and the desorption rate of the intermediates was low,favoring C_(2) generation.Density functional theory calculations indicated that the Cu^(0)/Cu^(+) interfaces exhibited a lower Gibbs free energy for the rate-determining step,enhancing C_(2)H_(4) formation.The Cu/Cu_(2)O catalyst also exhibited a low Cu d-band center,which enhanced the adsorption stability of *CO on the surface and facilitated C_(2)formation.This observa-tion explained the higher yield of C_(2) products at the Cu^(0)/Cu^(+) interface than that of H_(2) under rapid mass transfer.The results of the net present value model showed that the H-cell holds promising industrial prospects,contingent upon it being a catalyst with both high selectivity and high current density.This approach of integrating the structure and composition provides new insights for ad-vancing the CO_(2)RR towards high-current C_(2) products. 展开更多
关键词 Reduction of Co_(2) High current Dendritic structure Cu/Cu_(2)o H-cell
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Decomposition of a β-O-4 lignin model compound over solid Cs-substituted polyoxometalates in anhydrous ethanol: acidity or redox property dependence? 被引量:1
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作者 吴学众 焦文千 +4 位作者 李秉正 黎演明 张亚红 王全瑞 唐颐 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第7期1216-1228,共13页
Production o f aromatics from lignin has attracted much attention. Because of the coexistence of C-O and C-C bonds and their complex combinations in the lignin macromolecular network, a plausible roadmap for de... Production o f aromatics from lignin has attracted much attention. Because of the coexistence of C-O and C-C bonds and their complex combinations in the lignin macromolecular network, a plausible roadmap for developing a lignin catalytic decomposition process could be developed by exploring the transformation mechanisms of various model compounds. Herein, decomposition of a lignin model compound, 2-phenoxyacetophenone (2-PAP), was investigated over several ce-sium-exchanged polyoxometalate (Cs-POM) catalysts. Decomposition of 2-PAP can follow two dif-ferent mechanisms: an active hydrogen transfer mechanism or an oxonium cation mechanism. The mechanism for most reactions depends on the competition between the acidity and redox proper-ties of the catalysts. The catalysts of POMs perform the following functions: promoting active hy-drogen liberated from ethanol and causing formation of and then temporarily stabilizing oxonium cations from 2-PAP. The use of Cs-PMo, which with strong redox ability, enhances hydrogen libera-tion and promotes liberated hydrogen transfer to the reaction intermediates. As a consequence, complete conversion of 2-PAP (〉99%) with excellent selectivities to the desired products (98.6% for phenol and 91.1% for acetophenone) can be achieved. 展开更多
关键词 Lignin model compound β-o-4 ether bond PoLYoXoMETALATE Hydrogen transfer mechanism oxonium cation mechanism Anhydrous ethanol
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Adaptive predictive functional control based on Takagi-Sugeno model and its application to pH process 被引量:5
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作者 苏成利 李平 《Journal of Central South University》 SCIE EI CAS 2010年第2期363-371,共9页
In order to obtain accurate prediction model and compensate for the influence of model mismatch on the control performance of the system and avoid solving nonlinear programming problem,an adaptive fuzzy predictive fun... In order to obtain accurate prediction model and compensate for the influence of model mismatch on the control performance of the system and avoid solving nonlinear programming problem,an adaptive fuzzy predictive functional control(AFPFC) scheme for multivariable nonlinear systems was proposed.Firstly,multivariable nonlinear systems were described based on Takagi-Sugeno(T-S) fuzzy models;assuming that the antecedent parameters of T-S models were kept,the consequent parameters were identified on-line by using the weighted recursive least square(WRLS) method.Secondly,the identified T-S models were linearized to be time-varying state space model at each sampling instant.Finally,by using linear predictive control technique the analysis solution of the optimal control law of AFPFC was established.The application results for pH neutralization process show that the absolute error between the identified T-S model output and the process output is smaller than 0.015;the tracking ability of the proposed AFPFC is superior to that of non-AFPFC(NAFPFC) for pH process without disturbances,the overshoot of the effluent pH value of AFPFC with disturbances is decreased by 50% compared with that of NAFPFC;when the process parameters of AFPFC vary with time the integrated absolute error(IAE) performance index still retains to be less than 200 compared with that of NAFPFC. 展开更多
关键词 Takagi-Sugeno (T-S) model adaptive fuzzy predictive functional control (AFPFC) weighted recursive least square (WRLS) pH process
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B Cell Epitopes within VP1 of Type O Foot-and-mouth Disease Virus for Detection of Viral Antibodies 被引量:2
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作者 Shan-dian GAO Jun-zheng DU Hui-yun CHANG Guo-zheng CONG Jun-jun SHAO Tong LIN Shuai SONG Qing-ge XIE 《Virologica Sinica》 SCIE CAS CSCD 2010年第1期18-26,共9页
In this study, the coding region of type O FMDV capsid protein VP1 and a series of codon optimized DNA sequences coding for VP1 amino acid residues 141-160 (epitopel), tandem repeat 200-213 (epitope2 (+2)) and ... In this study, the coding region of type O FMDV capsid protein VP1 and a series of codon optimized DNA sequences coding for VP1 amino acid residues 141-160 (epitopel), tandem repeat 200-213 (epitope2 (+2)) and the combination of two epitopes (epitopel-2) was genetically cloned into the prokaryotic expression vector PPRoExHTb and pGEX4T-1, respectively. VP1 and the fused epitopes GST-E1, GST-E2 (+2) and GST-E1-2 were successfully solubly expressed in the cytoplasm of Escherichia coli and Western blot analysis demonstrated they retained antigenicity. Indirect VP1-ELISA and epitope ELISAs were subsequently developed to screen a panel of 80 field pig sera using LPB-ELISA as a standard test. For VP1-ELISA and all the epitope ELISAs, there were clear distinctions between the FMDV-positive and the FMDV-negative samples. Cross-reactions with pig sera positive to the viruses of swine vesicular disease virus that produce clinically indistinguishable syndromes in pigs or guinea pig antisera to FMDV strains of type A, C and Asia1 did not occur. The relative sensitivity and specificity for the GST-E1 ELISA, GST-E2 (+2), GST-E1-2 ELISA and VP1-ELISA in comparison with LPB-ELISA were 93.3% and 85.0%, 95.0% and 90%, 100% and 81.8%, 96.6% and 80.9% respectively. This study shows the potential use of the aforementioned epitopes as alternatives to the complex antigens used in current detection for antibody to FMDV structural proteins. 展开更多
关键词 Foot-and-mouth disease virus FMDV) SERoLoGY Epitope ELISA
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EFFICACY OF ACUPUNCTURE THERAPY ON A, B AND O BLOOD GROUPS ──Relationship between A, B, O blood groups and the acupuncture therapy
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作者 Amit Kr. Chakraborty Mrigendranath Gantait Biswapati Mukherjee 《World Journal of Acupuncture-Moxibustion》 2005年第2期18-20,共3页
Efficacy of acupuncture therapy varies in patients with similar ailments. The present study was undertaken to search for a marker for better efficacy of acupuncture therapy. The study was made in 224 patients includin... Efficacy of acupuncture therapy varies in patients with similar ailments. The present study was undertaken to search for a marker for better efficacy of acupuncture therapy. The study was made in 224 patients including osteoarthritis 141 (62.94 %), polyarthritis 23 (10.26 %), Bursitis & synovitis 15 (6.69 %) and others 45 (20.08 %). ABO blood groups were tested for each patient. It appears that patients belonging to group AB and B responded well to acupuncture therapy in proportionately more number. Good result was achieved in 47.82 % cases in group AB and 46.04 % cases in group B, whereas patients of group A and O showed good result in 27.65 % and 26.15 % cases respectively. Apparently it may be concluded that patients of AB & B blood groups would respond comparatively well to acupuncture therapy. 展开更多
关键词 Acupuncture efficacy ABo blood groups Acupuncture therapy
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A Takagi-Sugeno-Kang (TSK) Power Model Using Compressed-sensing Sampling
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作者 郭喜峰 王大志 刘炜 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1161-1166,共6页
More and more information are needed in social life and commercial production, causing significant pressure on the sampling and too much time spent on signal sampling. Compressed sensing is one emerging hotspot in sig... More and more information are needed in social life and commercial production, causing significant pressure on the sampling and too much time spent on signal sampling. Compressed sensing is one emerging hotspot in signal processing which employs a special sampling method to capture and represent compressible signals at a rate significantly below the Nyquist rate. In this paper, a Takagi-Sugeno-Kang (TSK) Model based on compressed-sensing sampling theorem is proposed for grinding power. It is further tested by using the actual production data, and the algorithm performance in grinding power model is also analyzed. The experiments show the validity and effectiveness of the proposed modeling method and its bright application foreground in other fields with similar features, such as power, metallurgy and so on. 展开更多
关键词 BENEFICIATIoN GRINDING Takagi-Sugeno-Kang compressed sensing
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Numerical Evaluation of Longitudinal Motions of Wigley Hulls Advancing in Waves by Using Bessho Form Translating-Pulsating Source Green's Function
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作者 XIAO Wenbin DONG Wencai 《Journal of Ocean University of China》 SCIE CAS 2016年第3期429-437,共9页
In the framework of 3D potential flow theory, Bessho form translating-pulsating source Green's function in frequency domain is chosen as the integral kernel in this study and hybrid source-and-dipole distribution ... In the framework of 3D potential flow theory, Bessho form translating-pulsating source Green's function in frequency domain is chosen as the integral kernel in this study and hybrid source-and-dipole distribution model of the boundary element method is applied to directly solve the velocity potential for advancing ship in regular waves. Numerical characteristics of the Green function show that the contribution of local-flow components to velocity potential is concentrated at the nearby source point area and the wave component dominates the magnitude of velocity potential in the far field. Two kinds of mathematical models, with or without local-flow components taken into account, are adopted to numerically calculate the longitudinal motions of Wigley hulls, which demonstrates the applicability of translating-pulsating source Green's function method for various ship forms. In addition, the mesh analysis of discrete surface is carried out from the perspective of ship-form characteristics. The study shows that the longitudinal motion results by the simplified model are somewhat greater than the experimental data in the resonant zone, and the model can be used as an effective tool to predict ship seakeeping properties. However, translating-pulsating source Green function method is only appropriate for the qualitative analysis of motion response in waves if the ship geometrical shape fails to satisfy the slender-body assumption. 展开更多
关键词 translating-pulsating source local-flow component wave component longitudinal motions Wigley hulls surface mesh
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Preparation and microstructure characterization of poly-sialate-disiloxo type of geopolymeric cement
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作者 张云升 孙伟 李宗津 《Journal of Central South University》 SCIE EI CAS 2009年第6期906-913,共8页
In order to investigate the influence of three key molar ratios (n(SiO2)/n(Al2O3), n(K2O)/n(Al2O3) and n(H2O)/n(K2O)), a total of nine potassium poly-sialate-disiloxo (K-PSDS) geopolymeric cement matri... In order to investigate the influence of three key molar ratios (n(SiO2)/n(Al2O3), n(K2O)/n(Al2O3) and n(H2O)/n(K2O)), a total of nine potassium poly-sialate-disiloxo (K-PSDS) geopolymeric cement matrices were designed according to orthogonal design principle. Subsequently, XRD, ESEM-EDXA and MAS-NMR techniques were employed to further characterize the microstructure of the most fully reacted geopolymeric cement matrix. The experimental results show that n(K2O)/n(Al2O3) has the most significant effect on compressive strength amongst the three ratios. The highest compressive strength (20.1 MPa) can be achieved when n(SiO2)/n(Al2O3)=6.5, n(K2O)/n(Al2O3)=0.8 and n(HEO)/n(K2O)=10.0. The FTIR spectra of nine PSDS geopolymeric cement matrices also indicate that geopolymeric cement matrix with the highest strength is the most fully reacted one and possesses the largest amount of geopolymeric cement products. The microscopic analysis reveals that PSDS geopolymeric cement matrix possesses structural characteristics similar to gel substances in having a wide range of Si endowments, but predominantly the framework molecular chains of Si partially replaced by 4-coordinated Al tetrahedral. 展开更多
关键词 geopolymeric cement poly-sialate-disiloxo PREPARATIoN MICRoSTRUCTURE
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Collective Hamiltonian for Multi-O(4) Model 被引量:1
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作者 GU Jian-Zhong Masato Kobayasi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期309-316,共8页
The collective Bamiltonian up to the fourth order for multi-O(4) model is derived based on the self-consistent collective-coordinate (SCC) method, which is formulated in the framework of the time-dependent Hartree... The collective Bamiltonian up to the fourth order for multi-O(4) model is derived based on the self-consistent collective-coordinate (SCC) method, which is formulated in the framework of the time-dependent Hartree-Bogoliubov (TDHB) theory. The validity of the collective Hamiltonian is checked in the two special cases of the multi-O(4) model: the case where the number of the shells is equal to one (a single j-shell case), and the case where the Hartree-Bogoliubov equilibrium point is spherical (the spherical case). The collective Hamiltonian constitutes a good starting point to study nuclear shape coexistence. 展开更多
关键词 self-consistent collective-coordinate method multi-o(4) model time-dependent Hartree-Bogoliubov theory collective Hamiltonian
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Simulation analysis for O-cell test of pile and the interaction of upper pile and lower pile
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作者 郑英杰 张克绪 张尔其 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第4期541-547,共7页
In this paper,the soil-pile system of O-cell test of pile is simplified as an axi-symmetric problem.By using aggregation of quadrilateral isoparametric elements to simulate pile and soil,setting Goodman's elements... In this paper,the soil-pile system of O-cell test of pile is simplified as an axi-symmetric problem.By using aggregation of quadrilateral isoparametric elements to simulate pile and soil,setting Goodman's elements between pile and soils,a method of numerical simulation analysis on O-cell test of pile is presented with the consideration of nonlinear mechanical behavior of soils and pile-soil interface.The method is applied to the analysis of a case of O-cell test of pile.The load-displacement curves and axial force curves of upper pile and lower pile obtained from the O-cell test of pile are fitted,and parameters of the mechanical model of soils and interface are determined.Analysis results validate that the numerical simulation analysis method put forward in this paper is applicable.Furthermore,the interaction and influence of upper pile and lower pile in the O-cell test are also studied with the method.The result shows that if load box is located in a soil layer with fine mechanical behavior,the interaction of upper pile and lower pile in O-cell test can be ignored generally. 展开更多
关键词 o-cell test of pile simulation analysis nonlinear behavior p-s curve interaction
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Phase Transitions of a Dilute O(n) Model
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作者 GUOWen-An HenkW.J.B1ote LIUYuan-Yuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第6期911-916,共6页
We investigate tricritical behavior of the O(n) model in two dimensions by means of transfer-matrix and finite-size scaling methods. For this purpose we consider an O(n) symmetric spin model on the honeycomb lattice w... We investigate tricritical behavior of the O(n) model in two dimensions by means of transfer-matrix and finite-size scaling methods. For this purpose we consider an O(n) symmetric spin model on the honeycomb lattice with vacancies; the tricritical behavior is associated with the percolation threshold of the vacancies. The vacancies are represented by face variables on the elementary hexagons of thelattice. We apply a mapping of the spin degrees of freedom model on a non-intersecting-loop model, in which the number n of spin components assumes the role of a continuously variable parameter. This loop model serves as a suitable basis for the construction of the transfer matrix.Our results reveal the existence of a tricritical line, parametrized by n, which connects the known universality classes of the tricritical Ising model and the theta point describing the collapse of a polymer. On the other side of theIsing point,the tricritical line extends to the n = 2 point describing a tricritical O(2) model. 展开更多
关键词 phase transition dilute o(n) model tricritical behavior transfer matrix
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关于“O°”型及“∞°”型未定式极限的一个定值方法
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作者 刘剑秋 《吉林广播电视大学学报》 2000年第4期38-,42,共2页
本文对“O°”’型及“∞°”型未定式的极限给出一个充分性定理。该定理在泰勒(Taylor)公式的支持下,经过等价无穷小量的代换,使上述复杂的未定式极限的计算化得简单、且有定量的结果,从而在相当宽泛的条件下,这两种未定式成... 本文对“O°”’型及“∞°”型未定式的极限给出一个充分性定理。该定理在泰勒(Taylor)公式的支持下,经过等价无穷小量的代换,使上述复杂的未定式极限的计算化得简单、且有定量的结果,从而在相当宽泛的条件下,这两种未定式成为定式。 展开更多
关键词 “o′”型 “∞′”型 泰勒(Taylor)公式 等价无穷小量 罗必达(L′Hospital)法则
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Constructing Covalent Triazine Frameworks/N-Doped Carbon-Coated Cu_(2)O S-Scheme Heterojunctions for Boosting Photocatalytic Hydrogen Production
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作者 Kaihui Huang Dejun Chen +4 位作者 Xin Zhang Rongchen Shen Peng Zhang Difa Xu Xin Li 《物理化学学报》 SCIE CAS 2024年第12期19-20,共2页
The development of efficient photocatalysts for hydrogen production is crucial in sustainable energy research.In this study,we designed and prepared a Covalent Triazine Framework(CTF)-Cu_(2)O@NC composite featuring an... The development of efficient photocatalysts for hydrogen production is crucial in sustainable energy research.In this study,we designed and prepared a Covalent Triazine Framework(CTF)-Cu_(2)O@NC composite featuring an S-scheme heterojunction structure aimed at enhancing the photocatalytic hydrogen production.The light absorption capacity,electron-hole separation efficiency and H_(2)-evolution activity of the composite were significantly enhanced due to the synergistic effects of the nitrogen-doped carbon(NC)layer and the S-scheme heterojunction.Structural and photoelectrochemical characterization of the system reveal that the S-scheme heterojunctions not only enhance the separation efficiency of photogenerated carriers but also maintain the strong redox capabilities to further promote the photocatalytic reactions.Moreover,the NC layer could simultaneously reduce the photocorrosion of Cu_(2)O and promote the electron transfer.Experimental results demonstrate that the CTF-7%Cu_(2)O@NC composite shows outstanding hydrogen-production performance under visible light,achieving 15645μmol∙g^(−1)∙h^(−1),significantly surpassing the photocatalytic activity of pure CTF(2673μmol∙g^(−1)∙h^(−1)).This study introduces a novel approach to the development of efficient and innovative photocatalytic materials,strongly supporting the advancement of sustainable hydrogen energy. 展开更多
关键词 Photocatalytic hydrogen evolution Cu_(2)o@NC Covalent triazine frameworks(CTF) S-scheme heterojunction Nitrogen doped carbon
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Chemical synthesis of a cyclotide via intramolecular cyclization of peptide O-esters 被引量:5
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作者 ZHENG Ji-Shen CHANG Hao-Nan +1 位作者 SHI Jing LIU Lei 《Science China Chemistry》 SCIE EI CAS 2012年第1期64-69,共6页
Cyclotides constitute a fascinating family of circular proteins containing ca.30 amino acid residues.They have a unique cyclic cysteine knot topology and exhibit remarkable thermal,chemical and enzymatic stabilities.T... Cyclotides constitute a fascinating family of circular proteins containing ca.30 amino acid residues.They have a unique cyclic cysteine knot topology and exhibit remarkable thermal,chemical and enzymatic stabilities.These characteristics enable them to have a range of biological activities and promising pharmaceutical and agricultural applications.Here,we present a practical strategy for the chemical synthesis of cyclotides through the intramolecular ligation of fully unprotected peptide O-esters.This strategy involves the mild Fmoc solid-phase peptide synthesis of the peptide O-ester backbone,the head-to-tail cyclization of the cyclotide backbone by native chemical ligation,and the oxidative refolding to yield the natural knot protein.The simplicity and high efficiency of the strategy can be employed in the synthesis of artificial cyclotides for pharmaceutical applications. 展开更多
关键词 CYCLoTIDES chemical synthesis peptide o-ester native chemical ligation MACRoLACTAMIZATIoN
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Parameter estimation for generalized diffusion processes with reflected boundary 被引量:2
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作者 ZANG QingPei ZHANG LiXin 《Science China Mathematics》 SCIE CSCD 2016年第6期1163-1174,共12页
Reflected Ornstein-Uhlenbeck process is a process that returns continuously and immediately to the interior of the state space when it attains a certain boundary. It is an extended model of the traditional Ornstein-Uh... Reflected Ornstein-Uhlenbeck process is a process that returns continuously and immediately to the interior of the state space when it attains a certain boundary. It is an extended model of the traditional Ornstein-Uhlenbeck process being extensively used in finance as a one-factor short-term interest rate model. In this paper, under certain constraints, we are concerned with the problem of estimating the unknown parameter in the reflected Ornstein-Uhlenbeck processes with the general drift coefficient. The methodology of estimation is built upon the maximum likelihood approach and the method of stochastic integration. The strong consistency and asymptotic normality of estimator are derived. As a by-product of the use, we also establish Girsanov's theorem of our model in this paper. 展开更多
关键词 reflected ornstein-Uhlenbeck process maximum likelihood estimation Girsanov's formula Sko-rohod embedding Dambis Dubins-Schwartz Brownian motion
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Application of the O-line model to martensite crystallography
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作者 GU XinFu ZHANG WenZheng 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第2期464-469,共6页
The O-line model is usually applied to precipitation crystallography.Its application to investigation of martensite crystallography has received little attention.In this paper,the relationship between O-line model and... The O-line model is usually applied to precipitation crystallography.Its application to investigation of martensite crystallography has received little attention.In this paper,the relationship between O-line model and the prism matching model for martensite crystallography is established.The formulas in the O-line model are applicable to martensite crystallography.Analytical solution of the habit plane corresponding to the minimum shape strain has been derived.A calculation example of {3 10 15}f martensite in a ferrous alloy is provided.While the results are in agreement with the former models for martensite crystallography,the advantage of O-line model is that it offers analytical solutions,facilitating further systematic investigations. 展开更多
关键词 habit plane o-line model martensite crystallography PTMC
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