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Chinese Physics Letters 2013年第6期30卷 29-33页

作者： LI feng-Bo ZONG feng-De WANG ying Institute of Nonlinear Physics Zhejiang Normal UniversityJinhua 321004

We study Bose–Einstein condensate vortical solitons under both a bichromatic optical lattice and anharmonic *** vortical solitons are built in the form of a layer-chain structure made up of two fundamental vortices along the bichromatic optical lattice direction,which have not been reported before in the three-dimensional Bose–Einstein condensate.A variation approach is applied to find the optimum initial solutions of vortical *** stabilities of the vortical solitons are confirmed by the numerical simulation of the time-dependent Gross–Pitaevskii *** particular,stable Bose–Einstein condensate vortical solitons with fundamental vortices of different atomic numbers in the external potential within a range of experimentally achievable timescales are *** further manipulate the vortical solitons to an arbitrary position by steadily moving the bichromatic optical lattice,and find a stable region for the successful manipulation of vortical solitons without *** results provide insight into controlling and manipulating the Bose–Einstein condensate vortical solitons for macroscopic quantum applications.

关键词： equation. Einstein solitons

First-Principles Investigation on the Fully Compensated Ferrimagnetic Behavior in Ti_2NbSb and TiZrNbSb

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Chinese Physics Letters 2019年第6期36卷 44-48页

作者： Lin feng Xue-ying zhang Department of Physics Taiyuan University of Technology

The electronic structures of Ti_2NbSb with Hg_2CuTi structure and TiZrNbSb with LiMgPdSn structure are investigated using first-principles *** results indicate that Ti_2NbSb is a fully compensated ferrimagnetic spin-gapless semiconductor with an energy gap of 0.13 e V,and TiZrNbSb is a half-metallic fully compensated ferrimagnet with a half-metallic gap of 0.17 e *** Ti_2NbSb,the total energy of the Hg_2CuTi structure is0.62 e V/*** than that of the L2_(1) structure,which is the ground state,and for TiZrNbSb,the total energy of the structure considered in this work is only 0.15 e V/*** than that of the ground *** both of them may be good candidates for spintronic applications.

关键词： First-Principles Investigation Fully Compensated Ferrimagnetic Behavior Ti2NbSb TiZrNbSb

Constrains of eruption environment and hydrothermal fluid on the Permian pyroclastic reservoirs in the Sichuan Basin,SW China

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Petroleum 2022年第1期8卷 17-30页

作者： xiaohong Liu Yiqian zhuo Mingyou feng Benjian zhang Maolong Xia Xingzhi Wang School of Geoscience and Technology Southwest Petroleum UniversityChengdu610500China Natural Gas Geology Key Laboratory of Sichuan Province Chengdu610500China Northwest Sichuan Mining District PetroChina Southwest Oil and Gas Filed CompanyJiangyou621709China PetroChina Southwest Oil and Gas Field Company Exploration and Development Research Institute Chengdu610041China

A breakthrough has been recently made in the hydrocarbon exploration of the Permian pyroclastic rocks in the Jianyang Area,western Sichuan Basin,*** an aim to decipher the impacts of the eruption environment,the temperature of hydrothermal fluids,and the paleo-salinity on the formation of authigenic mineral assemblage and pores,this study implements comprehensive petrographic and geochemical studies through the integrated core and thin section *** data presented demonstrate that the Permian volcanic intervals are intensively affected by an event of Emei *** basaltic magma upward migration,fractional crystallization of anorthose results in slightlyalkaline *** specific pyroclastic rocks are formed by the eruption of slightly-alkaline magma in the sea or a salt lake and subsequent hydrothermal *** deposition and diagenesis,the authigenic mineral association is constrained jointly by the sodium-rich and high salinity water environment,and mid-high temperature,high-salinity hydrothermal ***,the sodium-rich hydrothermal fluid,which may sustain till the late diagenesis stage,caused pervasive albitization of pyroclastic rocks,then leading to mineral transformation and formation of a series of mineral ***,zeolitization of volcanic glass and vesicle-infillings of zeolite is an essential condition for later mineral transformation and *** of analcite,recrystallization induced by deep hydrothermal fluids,and both meteoric and deep burial dissolution expanding the micro-pore space ultimately formed porous pyroclastic reservoirs.

关键词： Permian Pyroclastic rock Eruption environment Hydrothermal fluid Sichuan basin Southwest China

Effects of Exogenous Trehalose on the Metabolism of Sugar and Abscisic Acid in Tomato Seedlings Under Salt Stress

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Transactions of Tianjin University 2019年第5期25卷 451-471页

作者： Yanchun feng Xiuyu Chen Yulong He xiaohong Kou zhaohui Xue School of Chemical Engineering and Technology Tianjin University

Salt stress a ects the growth and development of plants, which results in a decrease in crop quality and yield. In this study, we used tomato seedlings treated with salt and trehalose as experimental materials and analyzed them using the technique for order preference by similarity to ideal solution analysis to select the optimal trehalose concentration for treatment. We also determined the contents of sugar and abscisic acid (ABA) and detected the expression of genes involved in the metabolism of sugar and ABA by quantitative real-time PCR. Results showed that the optimal trehalose concentration was 2 mmol/L for tomato seedlings under salt stress. Exogenous trehalose decreased the starch content and increased the soluble sugar con- tent by a ecting the expression of genes related to the metabolism of starch and soluble sugar. Exogenous trehalose altered the accumulation and distribution of sugar by inducing the upregulation of sugar transporter genes. Furthermore, trehalose increased the ABA content to induce salt stress response by regulating the expression of genes related to the synthesis and metabolism of ABA. In conclusion, trehalose can e ectively alleviate salt stress and enhance salt tolerance of tomato. These ndings provide a novel perspective and a better resource to investigate the salt tolerance mechanism and a new method for alleviating salt stress in tomato.

关键词： Tomato Trehalose Salt stress Sugar metabolism Sugar transporter Abscisic acid

Molecular characterization and expression analysis of a novel dual-CRD C-type lectin in kuruma shrimp(Marsupenaeus japonicus)

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Acta Oceanologica Sinica 2015年第2期34卷 74-83页

作者： zhANG Man MAO Yong WANG Jun feng Wenrong SONG xiaohong SU Yongquan College of Ocean and Earth Sciences Xiamen University

C-type lectins are among the most significant pattern recognition receptors（PRRs） found in invertebrate. They are a class of carbohydrate-binding proteins that can recognize specific sugar moieties on the surface of pathogens. In the present study, a novel C-type lecitn（termed Mj Lectin） from kuruma shrimp Marsupenaeus japonicus was identified. The full-length c DNA of Mj Lectin was 1 245 bp with a 1 011 bp open reading frame（ORF） that encoded a polypeptide of 336 amino acid residues. Mj Lectin consisted of two tandemly arrayed carbohydrate-recognition domains（CRDs）, unlike other reported M. japonicus C-type lectins with only one CRD. It showed a high similarity to other shrimp dual-CRD lectins. Among the Ca2＋-binding Site 2, the tripeptide motif dictating the carbohydrate binding specificity was exhibited as a rare mutant LPN（Leu134-Pro135-Asn136） in CRD1 and a traditional EPN（Glu299-Pro300-Asn301） in CRD2, respectively. Mj Lectin showed a specific expression pattern in both tissue and cellular levels, for its m RNA transcript was mainly expressed in the F-cells of the hepatopancreas. After white spot syndrome virus（WSSV） challenge（3.6×108 virions/μL）, the expression of Mj Lectin in the hepatopancreas was up-regulated significantly at 48 h（P〈0.01） compared with the control group. These results suggested that Mj Lectin might be involved in the innate immune defense against WSSV infection.

关键词： C-type lectin Marsupenaeus japonicus carbohydrate-recognition domain(CRD) gene expression white spot syndrome virus(WSSV)

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InSe单层中点缺陷的第一性原理研究

原子与分子物理学报 2025年第6期42卷 167-173页

作者：何诗颖谢瑞恬刘娟邹代峰赵宇清许英廖雨洁湖南科技大学物理与电子科学学院湘潭411201 智能传感器与新型传感器材料湖南省重点实验室湘潭411201 山西大学化学化工学院太原030006 武汉大学动力与机械学院武汉430072

InSe是Ⅲ-Ⅵ族化合物中的主要成员,由于其具有优异的电学性能,在太阳能电池、固体电池组等领域受到广泛的关注.光电材料及器件的优良特性由电子结构决定,而Ⅲ-Ⅵ族化合物中的点缺陷对电子结构具有重要的调控,且单层InSe中点缺陷的Perdew... 详细信息

InSe是Ⅲ-Ⅵ族化合物中的主要成员,由于其具有优异的电学性能,在太阳能电池、固体电池组等领域受到广泛的关注.光电材料及器件的优良特性由电子结构决定,而Ⅲ-Ⅵ族化合物中的点缺陷对电子结构具有重要的调控,且单层InSe中点缺陷的Perdew-Burke-Ernzerhof(PBE)和Heyd-Scuseria-Ernzerhof(HSE)对比研究尚且缺乏.本文基于密度泛函理论的第一性原理计算,对单层InSe的硒空位、铟空位、溴替代硒、硫替代硒、碲替代硒、镓替代铟、锡替代铟和铊替代铟的缺陷形成能和稳定性进行了研究.结果表明:在缺铟和富铟条件下,硫替代硒和镓替代铟的缺陷形成能低且可以有效的降低体系总能,提高体系的稳定性.溴替代硒具有较小的缺陷形成能,但较大的体系总能表明溴替代硒的缺陷体系不稳定.在缺铟条件下易形成铊替代铟缺陷;在富铟条件下易形成碲替代硒缺陷.上述研究结果有助于理解点缺陷对Ⅲ-Ⅵ族化合物稳定性的影响,同时也为未来实验上设计基于InSe的高效的光电子器件提供理论依据.

关键词：单层InSe 稳定性形成能点缺陷

Lung Nodules Detection in CT Images Using Gestalt-Based Algorithm

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Chinese Journal of Electronics 2016年第4期25卷 711-718页

作者： QIU Shi WEN Desheng CUI ying feng Jun Xi'an Institute of Optics and Precision Mechanics of CAS University of Chinese Academy of Sciences College of Equipment Engineering Engineering University of Chinese Armed Police Force School of Information Science and Technology Northwest University

To overcome low accuracy and high false positive of existing computer-aided lung nodules *** propose a novel lung nodule detection scheme based on the Gestalt visual cognition *** proposed scheme involves two parts which simulate human eyes cognition features such as simplicity,integrity and ***,lung region was segmented from lung Computed tomography(CT) *** local threedimensional information was integrated into the Maximum intensity pro jection(MIP) images from axial,coronal and sagittal *** this way,lung nodules and vascular are strengthened and discriminated based on pathologic image characteristics of lung *** experimental database includes fifty-three high resolution CT images contained lung nodules,which had been confirmed by *** experimental results show that,the accuracy rate of the proposed algorithm achieves 91.29%.The proposed framework improves performance and computation speed for computer aided nodules detection.

关键词： Computer-aided detection(CAD) Lung nodules Maximum intensity pro jection(MIP)

Dynamic Modeling and Analysis of 9-DOF Omnidirectional Legged Vehicle

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 515-521页

作者： GAO feng WANG Guofu CUI ying YANG Xinhong School of Transportation Science ＆ Engineering Beihang University Beijing 100191 China

The omnidirectional legged vehicle with steering-rails has a specific mechanism feature, and it can be controlled flexibly and accurately in omnidirectional motion. Currently there lacks further research in this area. In this paper, the mechanical characteristics of independent walking control and steering control and its kinematics principle are introduced, and a vehicle has a composite motion mode of parallel link mechanism and steering mechanism is presented. The motion direction control of the proposed vehicle is only dependant on its steering rails, so its motion is simple and effective to control. When the relative motion between the walking and steering is controlled cooperatively, the vehicle can walk perfectly. By controlling the steering rails, the vehicle can walk along arbitrary trajectory on the ground. To achieve a good result of motion control, an equivalent manipulator model needs to be built. In terms of the mechanism feature and the kinematic principle, the simplified manipulator model consists of a rail in stance phase, a rail in swing phase, and an equivalent leg. Considering the ground surface slope during walking, a parameter of inclination angle is added. Based on such a RPP manipulator model, the equations of motion are derived by means of Lagrangian dynamic approach. To verify the dynamic equations, the motion of the manipulator model is simulated based on linear and nonlinear motion planning. With the same model and motion parameters, the dynamic equations can be solved by Matlab and the calculation data can be gained. Compared with the simulation data, the result confirms the manipulator dynamic equations are correct. As a result of such special characteristics of the legged mechanism with steering rails, it has a potential broad application prospects. The derivation of dynamics equation could benefit the motion control of the mechanism.

关键词： legged vehicle omnidirectional motion steering rails dynamic modeling dynamic simulation

Crystal Structure and Characterization of Bis(4-isoniazidylthioformyl) Disulfide Hydration Sodium Coordination Polymer:n[(4-Pyridyl-CONHNCS_2)_2^(2-)]·[Na_2(H_2O)_8^(2+)]_n

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Chinese Journal of Structural Chemistry 2006年第6期25卷 740-746页

作者： WANG ying BEI feng-Li YAN Lian-He School of Chemical Engineering Nanjing Universityof Science and Technology Nanjing 210094 China

The title compound has been prepared and characterized by elemental analysis, infrared spectra, NMR and thermal analyses, and its crystal structure was determined by X-ray diffraction method. The crystal crystallizes in the monoclinic system, space group C2/c with a = 2.3066（5）, b = 0.53320（ 11）, c = 2.3236（5） nm,β= 102.76（3）°, V = 2.7872（ 10） nm^3, Mr = 612.67, Z = 4, Dc = 1.460 g/cm^3, R = 0.0570 and wR = 0.1271. In the title compound, two 4-isoniazidylthioformyl units are bridged by S-S bond （0.2037（3） nm）. The Na ions are linked by O（4）, O（4A）, O（1） and O（1A） to form a one-dimensional hydration sodium coordination polymer. The Na ion is coordinated by a meridional arrangement of the six O atoms to assume a slightly distorted octahedron as a result of intermolecular hydrogen bonds. The thermal analytical data indicate that it decomposes completely at the temperature of 609.26 ℃.

关键词： crystal structure bridging isoniazide coordination polymer

Algebraic Solution for the Forward Displacement Analysis of the General 6-6 Stewart Mechanism

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 56-62页

作者： WEI feng WEI Shimin zhANG ying LIAO Qizheng Automation School Beijing University of Posts and Telecommunications School of Mechanical and Power Engineering Henan Polytechnic University

The solution for the forward displacement analysis（FDA） of the general 6-6 Stewart mechanism（i.e., the connection points of the moving and fixed platforms are not restricted to lying in a plane） has been extensively studied, but the efficiency of the solution remains to be effectively addressed. To this end, an algebraic elimination method is proposed for the FDA of the general 6-6 Stewart mechanism. The kinematic constraint equations are built using conformal geometric algebra（CGA）. The kinematic constraint equations are transformed by a substitution of variables into seven equations with seven unknown variables. According to the characteristic of anti-symmetric matrices, the aforementioned seven equations can be further transformed into seven equations with four unknown variables by a substitution of variables using the Grobner basis. Its elimination weight is increased through changing the degree of one variable, and sixteen equations with four unknown variables can be obtained using the Grobner basis. A 40th-degree univariate polynomial equation is derived by constructing a relatively small-sized 9 × 9 Sylvester resultant matrix. Finally, two numerical examples are employed to verify the proposed method. The results indicate that the proposed method can effectively improve the efficiency of solution and reduce the computational burden because of the small-sized resultant matrix.

关键词： general 6-6 Stewart mechanism forward displacement analysis (FDA) conformal geometric algebra (CGA),Gr6bner basis Sylvester resultant