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Form Invariance and Conserved Quantity for Non-holonomic Systems with Variable Mass and Unilateral Constraints

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Communications in Theoretical Physics 2007年第2期47卷 213-216页

作者： WANG Jing LI Yuan-Cheng hou Qi-bao XIA Li-Li College of Physical Science and Technology University of Petroleum China Dongying 257061 China

The paper studies the form invariance and a type of non-Noether conserved quantity called Mei conserved quantity for non-holonomic systems with variable mass and unilateral constraints. Acoording to the invariance of the form of differential equations of motion under infinitesimal transformations, this paper gives the definition and criterion of the form invariance for non-holonomic systems with variable mass and unilateral constraints. The condition under which a form invariance can lead to Mei conservation quantity and the form of the conservation quantity are deduced. An example is given to illustrate the application of the results.

关键词： variable mass unilateral constraint non-holonomic system form invaxiance conserved quantity

Lie-Form Invariance of a Type of Non-holonomic Singular Systems

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Communications in Theoretical Physics 2007年第3期47卷 409-412页

作者： WANG Jing LI Yuan-Cheng hou Qi-bao XIA Li-Li College of Physical Science and Technology China University of Petroleum Dongying 257061 China

In this paper, the Lie-form invariance of a type of non-holonomic singular systems is studied. The differential equations of motion of the systems are given. The definition and the criterions of the Lie-form invariance for the systems are presented. The Hojman conserved quantity and the Mei conserved quantity are obtained. An example is given to illustrate the application of the results.

关键词： non-holonomic constraint singular system symmetry conserved quantity

Unified Symmetry of Nonholonomic System of Non-Chetaev＇s Type with Variable Mass in Event Space

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Communications in Theoretical Physics 2007年第4X期48卷 619-622页

作者： hou Qi-bao LI Yuan-Cheng XiA Li-Li WANG Jing College of Physics Science and Technology China University of Petroleum Dongying 257061 China

The unified symmetry of a nonholonomic system of non-Chetaev＇s type with variable mass in event space is studied. The differential equations of motion of the system are given. Then the definition and the criterion of the unified symmetry for the system are obtained. Finally, the Noether conserved quantity, the Hojman conserved quantity, and a new type of conserved quantity are deduced from the unified symmetry of the nonholonomic system of non-Chetaev＇s type with variable mass in event space at one time. An example is given to illustrate the application of the results.

关键词： event space nonholonomic system variable mass unified symmetry conserved quantity

Exosomal microRNAs in hepatocellular carcinoma,expanding research field

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World Journal of Gastroenterology 2024年第20期30卷 2618-2620页

作者： Bo-Hao Zheng Xiao-Jian Ni hou-bao Liu Department of Biliary Surgery Zhongshan HospitalFudan UniversityShanghai 200032China Biliary Tract Disease Center of Zhongshan Hospital Fudan UniversityShanghai 200032China Biliary Tract Disease Institute Fudan UniversityShanghai 200032China Cancer Center Zhongshan HospitalFudan UniversityShanghai 200032China Shanghai Biliary Tract Minimal Invasive Surgery and Materials Engineering Research Center Shanghai 200032China

In this editorial we comment on the review by Wang et al published in the recent issue of the World Journal of Gastroenterology in *** extracellular vesicles(exosomes)play important roles in the tumor *** this review,the authors introduce the following points:(1)The composition and function of exosomal microRNAs(miRNAs)of different cell origins in hepatocellular carcinoma(HCC);(2)the crosstalk between exosomal miRNAs from stromal cells and immune cells in the tumor microenvironment and the progression of HCC;and(3)the potential applicability of exosomal miRNAs derived from mesenchymal stem cells in the treatment of *** addition,the potential applicability of exosomal miRNAs derived from mesenchymal stem cells in the treatment of HCC was *** this review,the authors give us an overview of the exosomal RNA and summarize the function of exosomal RNA in HCC,which provides a deeper understanding of exosomal miRNAs to the readers.

关键词： Exosomes MicroRNA Hepatocellular carcinoma Liver cancer Tumor microenvironment

Unified Symmetry of Nonholonomic Mechanical Systems of Non-Chetaev＇s Type with Unilateral Constraints

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Communications in Theoretical Physics 2006年第6X期46卷 1081-1084页

作者： XIA Li-Li LI Yuan-Cheng WANG Jing hou Qi-bao College of Physical Science and Technology China University of Petroleum Dongying 257061 China

The definition and the criterion for a unified symmetry of nonholonomic mechanical systems of non- Chetaev＇s type with unilateral constraints are presented based on the total time derivative along the trajectory of the system. A new conserved quantity, as well as the Noether conserved quantity and the Hojman conserved quantity, deduced froth the unified symmetry, is obtained. An example is given to illustrate the application of the results.

关键词： unilateral constraints nonholonomic mechanical system of non-Chetaev's type unified symmetry conserved quantity

Improved energy storage performance of nanocomposites with Bi_(4.2)K_(0.8)Fe_(2)O_(9+δ) nanobelts

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Journal of Materiomics 2020年第2期6卷 371-376页

作者： Chuangming hou Zhiwei bao Haoyang Sun Yuewei Yin Xiaoguang Li Hefei National Laboratory for Physical Sciences at the Microscale Department of Physicsand CAS Key Laboratory of Strongly-coupled Quantum Matter PhysicsUniversity of Science and Technology of ChinaHefei230026China School of Physics and Materials Science Anhui UniversityHefei230601China Collaborative Innovation Center of Advanced Microstructures Nanjing210093China

Modern electronics and electric power grids require high performance polymer-based dielectric *** realize large-scale applications,the energy density of nanocomposites needs to be further ***,we demonstrate a remarkable improvement in energy density of poly(vinylidene fluoride)(PVDF)matrix upon the incorporation of high-k Bi_(4.2)K_(0.8)Fe_(2)O_(9+δ)(BKFO)*** aspect ratio BKFO nanobelts can enhance the Young's moduli of the nanocomposites and increase the path tortuosity of electrical trees,which are favorable for increasing the breakdown strength of the ***,the dielectric constant and breakdown strength increase simultaneously at a low volume fraction(0.35 vol%)of BKFO nanobelts,and an ultrahigh recoverable energy density of 25.4 J/cm^(3) is *** results provide a strategy to develop high performance flexible high-energy-density devices.

关键词： Dielectric nanocomposite Energy storage Nanobelt Breakdown strength

Lie-Form Invariance of the Nonholonomic System of Relative Motion in Event Space

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Communications in Theoretical Physics 2007年第5X期48卷 795-798页

作者： hou Qi-bao LI Yuan-Cheng WANG Jing XIA Li-Li College of Physics Science and Technology China University of Petroleum Dongying 257061 China

In this paper, the Lie-form invariance of a nonholonomic system of relative motion in event space is studied. Firstly, the definition and the criterion of the Lie-form invariance of the nonholonomic system of relative motion in event space is given. Secondly, the Hojman conserved quantity and a new type of conserved quantity deduced from the Lie-form invariance are obtained. An example is given to illustrate the application of the results.

关键词： event space nonholonomic system relative motion Lie-form invariance conserved quantity

Unified Symmetry of Nonholonomic System of Non-Chetaev＇s Type in Event Space

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Communications in Theoretical Physics 2007年第2期47卷 221-224页

作者： hou Qi-bao LI Yuan-Cheng WANG Jing XIA Li-Li College of Physics Science and Technology China University of Petroleum Dongying 257061 China

The unified symmetry of a nonholonomic system of non-Chetaev＇s type in event space under infinitesimal transformations of group is studied. Firstly, the differential equations of motion of the system are given. Secondly, the definition and the criterion of the unified symmetry for the system are obtained. Thirdly, a new conserved quantity, besides the Noether conserved quantity and the Hojman conserved quantity, is deduced from the unified symmetry of a nonholonomic system of non-Chetaev＇s type. Finally, an example is given to illustrate the application of the result.

关键词： event space nonholonomic system unified symmetry conserved quantity

Crystal Structure and DFT Studies of a Triazole Derivative: 4-(2-Hydrobenzylideneamino)-3-(1,2,4-triazol-4-yl-methyl)1H-1,2,4-triazole-5(4H)-thione

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Chemical Research in Chinese Universities 2007年第3期23卷 343-348页

作者： LI Wei-hua ZHANG Shu-fang LIU Fa-qian hou bao-rong Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 P. R. China Graduate School of the Chinese Academy of Sciences Beijing 100049 P. R. China Key Laboratory of Advanced Materials Qingdao University of Science and Technology Qingdao 266042 P. R. China

A novel triazole derivative 4-（ 2-hydrobenzylideneamino ） -3-（ 1,2,4-triazol-4-ylmethyl ） -1H-1,2,4-triazole-5 （4H）-thione（1） was synthesized and characterized using elemental analysis, FTIR, and 1^H NMR, and its crystal structure was determined via X-ray single crystal diffraction analysis. Crystal data： monoclinic, P2 （ 1 ）/c, a = 0. 83335（9） nm, b = 1. 49777（16） nm, c = 1. 14724（12） nm,β = 107. 990（2）°, D = 1. 470 Mg/m^3, and Z =4. The geometries and the vibrational frequencies were determined using the density functional theory（DFT） method at the B3LYP/6-31G^＊ level. To demonstrate the accuracy of the reaction route of compound 1, one of the important intermediates was also tested using the same method. The structural parameters of the two compounds calculated using the DFT study are close to those of the crystals, and the harmonic vibrations of the two compounds computed via the DFT method are in good agreement with those in the observed IR spectral data. The thermodynamic properties of the title compound were calculated, and the compound shows a good structural stability at normal temperature. The test results of biological activities show that it has a certain bactericidal ability.

关键词： Triazoles Synthesis Crystal structure DFT