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Chinese Journal of Chemical Physics 2006年第4期19卷 294-300页

作者： xiang-gui ni Yu Wang Zhong Zhang Xiu-xi Wang CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China Hefei 230025 China

Tensile deformation behaviors and the Poisson＇s ratio of single-walled carbon nanotubes （SWCNTs） are numerically studied, using the molecular dynamics （MD） inethod. Effects of several structural features of crystal cells of SWCNTs, i.e., the size, chirality and strain, on their mechanical properties are analyzed systematically. The simulations indicate that Armchair SWCNTs （8, 8）-（22, 22） and Zigzag SWCNTs （9,0）- （29,0） can be stretched by 35%-38% and 20%-27% without sign of plasticity, respectively. The Young＇s modulus of SWCNTs under tension ranges from 960 GPa to 750 GPa as their radii increase. The Young＇s modulus of zigzag SWCNTs is higher than that of armchair SWCNTs. Additionally, three SWCNTs （9,9）, （12,6） and （16,0） are investigated to obtain their Poisson＇s ratio under tensile and compressive loading. The results show that the Poisson＇s ratio of nanotubes decreases generally as the strain increases. Under the same tensile strain, the Poisson＇s ratio decreases as the chiral angles of SWCNTs decrease, while their Polsson＇s ratios increase under the same compressive strain.

关键词： Single-walled carbon nanotube Chiral dependence Size dependence Strain dependence Poisson's ratio

Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao xiang Feng Gao Yu-gui Peng Peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Bioassay of Estrogenic Activity of Effluent and Influent in a Farm Wastewater Treatment Plant Using an in vitro Recombinant Assay with Yeast Cells

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Biomedical and Environmental Sciences 2008年第5期21卷 381-388页

作者： xiang-MING LI FANG-ni LUO gui-XIA LIU AND PING-TING ZHU Department of Preventive Medicine Medical College Yangzhou University Yangzhou 225001 Jiangsu China College of Animal Science and Technology Yangzhou University Yangzhou 225009 Jiangsu China

Objective Environmental estrogens at an elevated concentration are known to produce adverse effects on human and animal life. However, the majority of researches have been focused on industrial discharges, while the impact of livestock wastes as a source of endocrine disrupters in aquatic environments has been rarely elucidated. In order to investigate the contribution of environmental estrogens from livestock, the estrogenic activity in water samples from a farm wastewater treatment plant was analyzed by a recombinant yeast screening method. Methods The extracts prepared from 15 selected water samples from the farm wastewater treatment plant, among which 6 samples were from pre-treatment section （influents） and 9 from post-treatment section （effluents）, were analyzed for estrogenic activity by cellar bioassay. Yeast cells transfected with the expression plasmid of human estrogen receptor and the Lac Z reporter plasmid encoding β-galactossidase, were used to measure the estrogen-like compounds in the farm wastewater treatment plant. Results The wastewater samples from influents showed a higher estrogenic potency than the effluent samples showing a low induction of β-galactossidase relative to solvent control condition. By comparison with a standard curve for 17β-estradiol （E2）, estrogenic potency in water samples from the influents was calculated as E2-equivalent and ranged from 0.1 to 150 pM E2-equivalent. The estrogenic potency in water samples from the effluents was significantly lower than that in the influents, and 7 water samples had less detectable limit in the total of 9 samples. Conclusion Yeast bioassay of estrogenic activity in most of the samples from the farm wastewater after disposal by traditional sewage treatment showed negative results.

关键词： Farm wastewater Bioassay Recombinant gene yeast Environmental estrogens

Experimental isothermal section phase diagram of Ho-Fe-In at 773 K and magnetic properties of Ho_(12)Fe_(2.08)In_(2.92) alloy

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Rare Metals 2021年第4期40卷 987-994页

作者： xiang Chen Chao ni The College of Physics and Electronic Information Engineering Neijiang Normal UniversityNeijiang 641002China The Ames Laboratory U.S.Department of EnergyIowa State UniversityAmesIA 50011-3020USA

The isothermal section of the Ho-Fe-In system at 773 K has been constructed by X-ray powder *** known structure ternary compound Er_(12)Fe_(2) In_(3)-type Ho_(12)Fe_(2) In_(3) has been *** the same time,solid solutions are not detected in Ho-Fe-In system at 773 *** magnetic transition and magnetocaloric effect of Ho_(12)Fe_(2.08)In_(2.92) alloy with Er_(12)Fe_(2) In_(3)-type structure were investigated by magnetic susceptibility and isothermal magnetization *** normal antiferromagnetic-paramagnetic transition and another abnormal one are discovered at 18 and 76 K in ground state,*** to a first-order field-induced metamagnetic transition(antiferromagnetic-ferromagnetic) at/below the Neel temperature of 18 K),the negative entropy changes are observed at corresponding *** is only a second-order ferromagnetic-paramagnetic transition near Curie temperature(TC),the maximum entropy change(Δ_(Smax)) values are-6.14 J·kg^(-1)·K^(-1) at 3 K and 7.88 J·kg^(-1)·K^(-1) at 28 K in a field range of 0-7 *** reversible relative cooling power corresponding to negative entropy change can reach about 600 J·kg^(-1) in an wide operating temperature region Δ_(Tcycl)=74 K from 16 to90 K,which suggests that Ho_(12)Fe_(2.08)In_(2.92) could be a potential material for magnetic refrigeration in the corresponding temperature range.

关键词： Re_(3(x+y))(T2)_(x)X_(y)phase Metamagnetic transition Magnetothermal properties Ho-Fe-In alloy

The Cauchy Problem of the Nonlinear Schr■dinger Equations in R^(1+1)

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Acta Mathematicae Applicatae Sinica 2007年第4期23卷 593-610页

作者： gui-xiang Xu Institute of Applied Physics and Computational Mathematics P.O. Box 8009 Beijing 100088 China

In this paper, we consider the local and global solution for the nonlinear Schrodinger equation with data in the homogeneous and nonhomogeneous Besov space and the scattering result for small data. The techniques to be used are adapted from the Strichartz type estimate, Kato＇s smoothing effect and the maximal function （in time） estimate for the free SchrSdinger operator.

关键词： Schrodinger equation cauchy problem besov space littlewood-paley decomposition self-similar solution

Heading constraint algorithm for foot-mounted PNS using low-cost IMU

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Journal of Systems Engineering and Electronics 2022年第3期33卷 727-736页

作者： gui Jing ZHAO Heming XU xiang School of Electronic and Information Engineering Soochow UniversitySuzhou 215006China

Foot-mounted pedestrian navigation system(PNS)is a common solution to pedestrian navigation using micro-electro mechanical system(MEMS)inertial *** inherent problems of inertial navigation system(INS)by the traditional algorithm,such as the accumulated errors and the lack of observation of heading and altitude information,have become obstacles to the application and development of the *** this paper,we introduce a heuristic heading constraint *** of all,according to the movement characteristics of human gait,we use the generalized likelihood ratio test(GLRT)detector and introduce a time threshold to classify the human gait,so that we can effectively identify the stationary state of the *** addition,based on zero velocity update(ZUPT)and zero angular rate update(ZARU),the cumulative error of the inertial measurement unit(IMU)is limited and corrected,and then a heuristic heading estimation is used to constrain and correct the heading of the *** simulation and experiments with low-cost IMU,the method is proved to reduce the localization error of end-point to less than 1%of the total distance,and it has great value in application.

关键词： pedestrian navigation system(PNS) zero velocity update(ZUPT) gait detection heading constraint

Active control of turbulence for drag reduction based on the detection of near-wall streamwise vortices by wall information

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Acta Mechanica Sinica 2015年第4期31卷 512-522页

作者： Mingwei Ge Chunxiao Xu gui-xiang Cui School of Renewable Energy North China Electric Power University School of Aerospace Tsinghua University

The spatial relations between the measurable wall quantities （streamwise shear stress τwx, spanwise shear stress τwz, and pressure fluctuations Pw） and the near-wall streamwise vortices （NWSV） are investigated via direct numerical simulation （DNS） databases of fully developed turbulent channel flow at a low Reynolds number. In the stan- dard turbulent channel flow, the results show that all the wall measurable variables are closely associated with the NWSV. But after applying a stochastic interference, the relation based on τwx breaks down while the correlations based on Pw and τwz are still robust. Hence, two wall flow quantities based on Pw and τwz are proposed to detect the NWSV. As an appli- cation, two new control schemes are developed to suppress the near-wall vortical structures using the actuation of wall blowing/suction and obtain 16 % and 11% drag reduction, respectively.

关键词： Active control Measurable wall information Near-wall streamwise vortices Turbulent drag reduction

Catalytic performance and reaction mechanisms of NO removal with NH_(3) at low and medium temperatures on Mn-W-Sb modified siderite catalysts

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Journal of Environmental Sciences 2022年第5期34卷 126-139页

作者： guihuan Yao Yuliang Wei Keting gui xiang Ling School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China School of Energy and Environment Southeast UniversityNanjing 210096China

Iron-based catalysts have been explored for selective catalytic reduction(SCR)of NO due to environmentally benign characters and good SCR ***-W-Sb modified siderite catalysts were prepared by impregnation method based on siderite ore,and SCR perfor-mance of the catalysts was *** catalysts were analyzed by X-ray diffrac-tion,H_(2)-temperature-programmed reduction,Brunauer-Emmett-Teller,Thermogravimetry-derivative thermogravimetry and in-situ diffused reflectance infrared Fourier transform spectroscopy(DRIFTS).The modified siderite catalysts calcined at 450℃ mainly consist of Fe_(2)O_(3),and added Mn,W and Sb species are amorphous.3Mn-5W-1.5Sb-siderite catalyst has a wide temperature window of 180-360℃ and good N_(2) selectivity at low ***-situ DRIFTS results show NH_(4)^(+),coordinated NH_(3),NH_(2),NO_(3)^(-)species(bidentate),NO_(2)-species(nitro,nitro-nitrito,monodentate),and adsorbed NO_(2) can be discovered on the sur-face of Mn-W-Sb modified siderite catalysts,and doping of Mn will enhance adsorbed NO_(2) formation by synergistic catalysis with Fe^(3+).In addition,the addition of Sb can inhibit sulfates formation on the surface of the catalyst in the presence of SO_(2) and H_(2)***-dependent in-situ DRIFTS studies also indicate that both of Lewis and Br?nsted acid sites play a role in SCR of NO by ammonia at low *** mechanism of NO removal on the 3Mn-5W-1.5Sb-siderite catalyst can be discovered as a combination of Eley-Rideal and Langmuir-Hinshelwood mechanisms with three reaction *** mechanism of NO,oxidized by synergistic catalysis of Fe^(3+)and Mn^(4+/3+)to form NO_(2) among three pathways,reveals the reason of high NO_(x) conversion of the catalyst at medium and low temperatures.

关键词： Iron-based catalysts Mn-W-Sb In-situ diffused reflectance infrared Fourier transform spectroscopy Reaction mechanism Siderite Low and medium temperature

PCK1 dysregulation in cancer: Metabolic reprogramming, oncogenic activation, and therapeutic opportunities

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Genes & Diseases 2023年第1期10卷 101-112页

作者： Jin xiang Kai Wang ni Tang Key Laboratory of Molecular Biology for Infectious Diseases(Ministry of Education) Institute for Viral HepatitisDepartment of Infectious DiseasesThe Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010China

The last few decades have witnessed an advancement in our understanding of multiple cancer cell pathways related to metabolic *** of the most important cancer hallmarks,including aerobic glycolysis(the Warburg effect),the central carbon pathway,and multiple-branch metabolic pathway remodeling,enables tumor growth,progression,and *** carboxykinase1(PCK1),a key rate-limiting enzyme in gluconeogenesis,catalyzes the conversion of oxaloacetate to ***1 expression in gluconeogenic tissues is tightly regulated during *** tumor cells,PCK1 is regulated in a cell-autonomous manner rather than by hormones or nutrients in the extracellular ***,PCK1has ananti-oncogenic role in gluconeogenic organs(the liver and kidneys),but a tumor-promoting role in cancers arising from non-gluconeogenic *** studies have revealed that PCK1 has metabolic and non-metabolic roles in multiple signaling networks linking metabolic and oncogenic *** PCK1 expression results in the activation of oncogenic pathways,accompanied by metabolic reprogramming,to maintain *** this review,we summarize the mechanisms underlying PCK1 expression and regulation,and clarify the crosstalk between aberrant PCK1 expression,metabolic rewiring,and signaling pathway *** addition,we highlight the clinical relevance of PCK1 and its value as a putative cancer therapeutic target.

关键词： Gluconeogenesis Metabolism Oncogenesis PCK1 Tumor

Long Time Dynamics of the 3D Radial NLS with the Combined Terms

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Acta Mathematica Sinica,English Series 2016年第5期32卷 521-540页

作者： gui xiang XU Jian Wei Yang Institute of Applied Physics and Computational Mathematics P.O.Box 8009Beijing 100088P.R.China Beijing International Center for Mathematical Research Peking UniversityBeijing 100871P.R.China

In this paper, we study the scattering and blow-up dichotomy result of the radial solution to nonlinear Schrodinger equation （NLS） with the combined termsiut＋△u=-｜u｜^4u＋｜u｜^p-1u,1＋4/3〈p〈5in energy space H^1（R^3）. The threshold energy is the energy of the ground state W of the focusing, energy critical NLS, which means that the subcritical perturbation does not affect the determination of threshold, but affects the scattering and blow-up dichotomy result with subcriticM threshold energy. This extends algebraic perturbation in a previous work of Miao, Xu and Zhao [Comm. Math. Phys., 318, 767-808 （2013）] to all mass supercritical, energy subcritical perturbation.

关键词： Blow up dynamics nonlinear SchrSdinger equation scattering threshold energy