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Communications in Theoretical Physics 2006年第5X期46卷 843-844页

作者： LAI mei-mei wang Xin XIAO Yan-Ping LIU Quan-Hui School for Theoretical Physics and Department of Applied Physics Hunan University Changsha 410082 China

When the motion of a particle is constrained, excess terms exist using hermitian form of Cartesian momentum pi （i=1, 2,3） in usual kinetic energy （1/2/μ）∑ pi^2 , and the correct kinetic energy turns out to be （1/2μ） ∑1/ fipi f ipi, where fi are dummy factors in classical mechanics and nontrivial in quantum mechanics. In this paper the explicit form of the dummy functions fi is given for a charged rigid planar rotator in the uniform magnetic field with different gauge chosen. Under different gauges, we have different sets of dummy factors. It means that these factors do not have direct observable effect.

关键词： operator ordering gauge transformation quantum mechanics

Characterizations of semihoops based on derivations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 291-310页

作者： wang mei ZHANG Xiao-hong School of Electrical and Control Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Arts and Sciences Shaanxi University of Science and TechnologyXi'an 710021China School of Mathematics and Statistics Weinan Normal UniversityWeinan 714099China

In this paper,we discuss the related properties of some particular derivations in semihoops and give some characterizations of ***,we prove that every Heyting algebra is isomorphic to the algebra of all multiplicative derivations and show that every Boolean algebra is isomorphic to the algebra of all implicative ***,we show that the sets of multiplicative and implicative derivations on bounded regular idempotent semihoops are in oneto-one correspondence.

关键词： (prelinear)semihoop derivation Heyting algebra Galois connection

Compensation temperatures and hysteresis behaviors of a graphene-like trilayer

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Communications in Theoretical Physics 2024年第5期76卷 166-179页

作者： Ying An Ji Liang Wei wang mei-mei Du Feng-ge Zhang School of Science Shenyang University of TechnologyShenyang 110870China School of Electrical Engineering Shenyang University of TechnologyShenyang 110870China

This work focuses on the ground-state phase diagram,the compensation temperatures and the critical behaviors of a ferrimagnetic graphene-like trilayer induced by crystal fields and exchange *** simulation results show that a negative decrease in crystal field or an increase in exchange coupling can increase the critical *** importantly,an M curve with double compensation temperatures can be observed,which is not predicted by the Neel *** remarkable compensation phenomenon has potential application value in the field of magnetic recording.

关键词： graphene-like trilayer mixed-spin Ising model magnetization double compensation temperatures triple-loop hysteresis monte Carlo

Metadherin promotes stem cell phenotypes and correlated with immune infiltration in hepatocellular carcinoma

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World Journal of Gastroenterology 2024年第8期30卷 901-918页

作者： Yi-Ying wang mei-mei Shen Jian Gao Department of Gastroenterology The Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010China Department of Gastroenterology and Hepatology The Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010China

BACKGROUND Metadherin(MTDH)is a key oncogene in most cancer types,including hepato-cellular carcinoma(HCC).Notably,MTDH does not affect the stemness pheno-type or immune infiltration of *** To explore the role of MTDH on stemness and immune infiltration in *** MTDH expression in HCC tissues was detected using TCGA and GEO *** was used to analyze the tissue *** was stably knocked down or overexpressed by lentiviral transfection in the two HCC cell *** invasion and migration abilities of HCC cells were evaluated using Matrigel invasion and wound healing ***,we obtained liver cancer stem cells from the spheroids by culturing them in a serum-free *** expression was determined by western blotting and quantitative reverse transcri-ption *** cytometry,immunofluorescence,and tumor sphere formation assays were used to characterize stem-like *** effects of MTDH inhibition on tumor growth were evaluated in *** correlation of MTDH with immune cells,immunomodulators,and chemokines was analyzed using ssGSEA and TISIDB *** HCC tissues expressed higher levels of MTDH than normal liver *** MTDH expression was associated with a poor *** cells overex-pressing MTDH exhibited stronger invasion and migration abilities,exhibited a stem cell-like phenotype,and formed spheres;however,MTDH inhibition attenuated these *** inhibition suppressed HCC progression and CD133 expression in *** was positively correlated with immature dendritic,T helper 2 cells,central memory CD8^(+)T,memory B,activated dendritic,natural killer(NK)T,NK,activated CD4^(+)T,and central memory CD4^(+)T *** was negatively correlated with activated CD8^(+)T cells,eosinophils,activated B cells,monocytes,macrophages,and mast cells.A positive correlation was observed between the MTDH level and CXCL2 expression,whereas a negative correlation was observed between the MTDH level and CX3CL1 a

关键词： Metadherin Hepatocellular carcinoma Cancer stem cells Immune infiltration

Graphdiyne(C_(n)H_(2n-2))as an"electron transfer bridge"boosting photocatalytic hydrogen evolution over Zn_(0.5)Co_(0.5)S/MoS_(2)S-scheme heterojunction

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Rare Metals 2024年第5期43卷 1999-2014页

作者： mei Li Jing-Zhi wang Zhi-Liang Jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyKey Laboratory for Chemical Engineering and TechnologyState Ethnic Affairs CommissionNorth Minzu UniversityYinchuan 750021China

In the process of photocatalytic water cracking,the migration rate and utilization rate of photogenerated charges determine the hydrogen evolution performance of the *** this paper,a carbon isotope superconducting material graphdiyne(GDY)is prepared by mechanical ball milling and introduced into the S-scheme heterojunction Zn_(0.5)Co_(0.5)S/MoS_(2)inorganic *** terms of hydrogen evolution kinetics,GDY acts as an electron bridge,not only accelerating the migration of photogenerated carriers but also improving the utilization of photogenerated ***,the large twodimensional layer provides more loading and anchoring points for Zn_(0.5)Co_(0.5)S/MoS_(2),which increases the number of active *** ternary composite catalyst 20%GDY/Zn_(0.5)Co_(0.5)S/MoS_(2)(20-GCSM)generates 69.94μmol of hydrogen(5 h)in triethanolamine *** is 2.97 and1.80 times higher than Zn_(0.5)Co_(0.5)S and Zn_(0.5)Co_(0.5)S/MoS_(2),*** the cyclic experiment,it still has stable hydrogen evolution performance after standing for24 h(under dark conditions).In addition,the potential mechanism of photocatalytic hydrogen evolution is demonstrated through in-situ X-ray photoelectron *** work provides a reference for further research in the field of introducing carbon materials into photocatalytic systems and improving the utilization of photogenerated charges.

关键词： Graphdiyne S-scheme heterojunction Electron transfer bridge Hydrogen production

A new method for identifying flow pattern of spouted fluidized bed by coupling Hilbert-Huang transform characteristics of differential pressure signals in different zones

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Particuology 2024年第6期89卷 67-78页

作者： Yongzhi mei Yang wang Lihui Zhang Feng Duan School of Energy and Environment Anhui University of TechnologyMaanshan243002China Wuhu Technology and Innovation Research Institute Wuhu241000China Wuhu Cigarette Factory of China Tobacco Anhui Industrial Co. Ldt.Wuhu241002China

On a cold spouted fluidized bed,this study compares the characteristic differences in intrinsic mode function(IMF)energy and Hilbert–Huang spectrum between the spout zone and annulus zone under different combinations of spouted gas and fluidized gas flow rates for five typical flow *** energy distribution characteristics under different flow patterns are also *** Hilbert–Huang spectrum and IMF energy of pressure difference signals exhibit distinct variations in different zones as the flow pattern ***,there exists a correlation between the energy in the middle-frequency range and the flow *** the K-means algorithm,the middle-frequency range energy of IMFs in the spout zone and annulus zone is subjected to clustering analysis,leading to the identification of partition boundaries for each flow *** on this,a flow pattern identification method of spouted fluidized bed coupled with middle-frequency range energy in spout zone and annulus zone is proposed,which has very high identification accuracy.

关键词： Spouted fluidized bed Flow pattern Zoning signal Flow pattern transition Hilbert-Huang transform

Photocatalytic reduction of CO_(2) with H_(2)O into C_(2)H_(6) mediated by dual metalation strategy

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Science China Chemistry 2024年第5期67卷 1381-1383页

作者： mei wang Tong-Bu Lu School of Materials Science and Engineering Institute for New Energy Materials&Low Carbon TechnologiesTianjin University of TechnologyTianjin 300384China

Artificial solar-energy-driven CO_(2) reduction into value-added fuels under mild conditions provides a promising strategy to mitigate energy crisis and alleviate environmental issues around the world. Among diverse products of CO_(2) reduction reaction, C_(2+) compounds are more desirable in terms of their high energy density and commercial value [1].Thus far, various photocatalysts have been constructed for CO_(2) reduction.

关键词： reduction desirable value

Multiscale Characteristics and Connection Mechanisms of Attraction Networks:A Trajectory Data Mining Approach Leveraging Geotagged Data

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Chinese Geographical Science 2024年第3期34卷 533-547页

作者： JIANG Hongqiang WEI Ye mei Lin wang Zhaobo School of Resource and Environment Engineering Ludong UniversityYantai 264025China School of Geographical Sciences Northeast Normal UniversityChangchun 130024China Changchun University of Finance and Economics Changchun 130122China Jilin Jizhi City Architectural Design Co. LTDChangchun 130012China

Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and connection mechanisms of attraction networks is important for understanding the linkages between attractions and even the future destination *** paper uses geotagging data to compare the links between attractions in Beijing,China during four different periods:the pre-Olympic period(2004–2007),the Olympic Games and subsequent‘heat period’(2008–2013),the post-Olympic period(2014–2019),and the COVID-19(Corona Virus Disease 2019)pandemic period(2020–2021).The aim is to better understand the evolution and patterns of attraction networks at different scales in Beijing and to provide insights for tourism planning in the *** results show that the macro,meso-,and microscales network characteristics of attraction networks have inherent logical relationships that can explain the commonalities and differences in the development process of tourism *** macroscale attraction network degree Matthew effect is significant in the four different periods and exhibits a morphological monocentric structure,suggesting that new entrants are more likely to be associated with attractions that already have high *** mesoscale links attractions according to the common purpose of tourists,and the results of the community segmentation of the attraction networks in the four different periods suggest that the functional polycentric structure describes their clustering effect,and the weak links between clusters result from attractions bound by incomplete information and distance,and the functional polycentric structure with a generally more efficient network of *** pattern structure at the microscale reveals the topological transformation relationship of the regional collaboration pattern,and the attraction network structure in the four diff

关键词： attraction network travel mobility polycentric structure network motif connectivity mechanism destination management organization(DMO) destination planning Beijing,China

Asymmetric two-dimensional diffraction grating via a vortex field in an inverted-Ytype atomic system

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Communications in Theoretical Physics 2024年第5期76卷 77-85页

作者： Duo Zhang Ke wang Kunpeng Zhao mei wang Zhaoyu Sun School of Electrical and Electronic Engineering Wuhan Polytechnic UniversityWuhan 430023China

We propose a theoretical scheme to realize a two-dimensional(2D)diffraction grating in a four-level inverted-Y-type atomic system coupled by a standing-wave(SW)field and a Laguerre-Gaussian(LG)vortex *** to asymmetric spatial modulation of the LG vortex field,the incident probe field can be lopsidedly diffracted into four domains and an asymmetric 2D electromagnetically induced grating is *** adjusting the detunings of the probe field and the LG vortex field,the intensities of the LG vortex field and the coherent SW field,as well as the interaction length,the diffraction properties and efficiency,can be effectively *** addition,the effect of the azimuthal parameter on the Fraunhofer diffraction of the probe field is also *** asymmetric 2D diffraction grating scheme may provide a versatile platform for designing quantum devices that require asymmetric light transmission.

关键词： asymmetric diffraction grating standing-wave field Laguerre-Gaussian vortex field diffraction property

Thermal runaway evolution of a 280 Ah lithium-ion battery with LiFePO_(4) as the cathode for different heat transfer modes constructed by mechanical abuse

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Journal of Energy Chemistry 2024年第6期93卷 32-45,I0002页

作者： Zhixiang Cheng Chengdong wang Wenxin mei Peng Qin Junyuan Li Qingsong wang State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026AnhuiChina

Lithium iron phosphate batteries have been increasingly utilized in recent years because their higher safety performance can improve the increasing trend of recurring thermal runaway ***,the safety performance and mechanism of high-capacity lithium iron phosphate batteries under internal short-circuit challenges remain to be *** work analyzes the thermal runaway evolution of high-capacity LiFePO_(4) batteries under different internal heat transfer modes,which are controlled by different penetration *** penetration cases involving complete penetration and incomplete penetration were detected during the test,and two modes were performed incorporating nails that either remained or were removed after penetration to comprehensively reveal the thermal runaway mechanism.A theoretical model of microcircuits and internal heat conduction is also *** results indicated three thermal runaway evolution processes for high-capacity batteries,which corresponded to the experimental results of thermal equilibrium,single thermal runaway,and two thermal runaway *** difference in heat distribution in the three phenomena is determined based on the microstructure and material structure near the *** controlling the heat dissipation conditions,the time interval between two thermal runaway events can be delayed from 558 to 1417 s,accompanied by a decrease in the concentration of in-situ gas production during the second thermal runaway event.

关键词： Lithium-ion battery safety Micro short-circuit cell Heat transfer modes Internal short circuit Nail-penetration test