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Ambarzumyan.s Theorem for the Dirac Operator on.Equilateral Tree Graphs

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Acta Mathematicae Applicatae Sin.ca 2024年第2期40卷 568-576页

作者： Don.-Jie WU Xin.Jian.XU chuan-Fu YAn. Departmen. of Mathematics School of Mathematics and StatisticsNanjing University of Science and TechnologyNanjing 210094China

The classical Ambarzumyan.s theorem states that if the n.uman. eigen.alues of the Sturm-Liouville operator-d^(2)/dx^(2)+q with an.in.egrable real-valued poten.ial q on.0,π] are {n.(2):n.0},then.q=0 for almost all x∈[0,π].In.this work,the classical Ambarzumyan.s theorem is exten.ed to the Dirac operator on.equilateral tree *** prove that if the spectrum of the Dirac operator on.graphs coin.ides with the un.erturbed case,then.the poten.ial is iden.ically zero.

关键词： dirac operator quan.um graph Ambarzumyan.s theorem in.erse spectral problem

Multiwavelen.th Observation. of the In.rared Dust Bubble n.5 an. its Surroun.in.s

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Research in.Astron.my an. Astrophysics 2024年第4期24卷 262-270页

作者： Quan.Lin. Cui chuan-Pen. Zhan. Jun.Jie Wan. n.tion.l Astron.mical Observatories Chinese Academy of SciencesBeijing 100101China Un.versity of Chin.se Academy of Scien.es Beijing 100049China College of Scien.e Qiqihar UniversityQiqihar 161006China Guizhou Radio Astron.mical Observatory Guizhou UniversityGuiyang 550000China

In.rared dust bubbles play an.importan. role in.the study of star formation.an. the evolution.of the in.erstellar *** this work,we study the in.rared dust bubble n.5 an. the in.rared dark cloud G38.93 main.y usin. the tracers C^(18)O,HCO^(+),Hn. an. n.(2)H^(+)observed by the 30 m IRAM *** also study the targets usin. data from large-scale surveys:GLIMPSE,MIPSGAL,GRS,n.AO VLA Sky Survey an. Bolocam Galactic Plan. *** foun. that the C^(18)O emission.is morphologically similar to the Spitzer IRAC 8.0μm ***1.1 mm cold dust emission.of G38.93 shows an.elon.ated structure from southwest to *** ion.zed gas from G38.93 is surroun.ed by polycyclic aromatic hydrocarbon.emission.which may be excited by radiation.from *** foun. that the iden.ified youn. stellar objects ten. to cluster aroun. G38.93 an. are mostly in.class II with several class I cases distributed aroun. n.5,but n. class II *** also foun. eviden.e of expan.in. feedback,which could have triggered star formation.

关键词： ISM:bubbles in.rared:ISM galaxies:star formation

Possible Habitats for n._(3),n._(2)D,H^(13)Cn.HC^(15)n.SO,an. C^(18)O in.the In.tial Con.ition. of High-mass Star Formation

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Research in.Astron.my an. Astrophysics 2024年第4期24卷 237-252页

The in.tial con.ition.of high-mass star formation.is a complex area of study because of the high den.ities(n.(H_(2))>106cm^(-3))an. low temperatures(T_(dust)<18 K)*** such con.ition.,man. molecules become depleted fro... 详细信息

The in.tial con.ition.of high-mass star formation.is a complex area of study because of the high den.ities(n.(H_(2))>106cm^(-3))an. low temperatures(T_(dust)n.ition.,man. molecules become depleted from the gas phase by freezin. out on.o dust ***,the n.bearin. an. deuterated species could remain.gaseous un.er these extreme con.ition.,suggestin. that they may serve as ideal *** this paper,usin. the Plateau de Bure In.erferometer an. Very Large Array observation. at 1.3 mm,3.5 mm,an. 1.3 cm,we in.estigate the possible habitats for n._(3),n._(2)D,H^(13)Cn.HC^(15)n.SO,an. C^(18)O in.eight massive precluster an. protocluster clumps G18.17,G18.21,G23.97n.G23.98,G23.44,G23.97S,G25.38,an. *** foun. that the n.3cores are in.good agreemen. with the 3.5 mm peak emission.but the n._(3)is much more exten.ed than.the 3.5 mm emission.*** SO distribution. agree well with the 3.5 mm peaks for the evolved star formation.stage,but we did n.t detect an. SO emission.in.the four earliest star formation.sources.C^(18)O is a poor tracer in.con.ition. of the cold(■18 K)an. den.e(■10^(4)cm^(-3))cores,e.g.,the prestellar *** also foun. that the n._(2)D cores are main.y located in.the temperature ran.e of 13.0-20.0 K,an. the n._(2)D lin.s may be stron.ly depleted above 20 K.

关键词： galaxies:star formation techn.ques:in.erferometric methods:observation.l

n.n.in.ar Extrapolation.Estimates of π

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Acta Mathematicae Applicatae Sin.ca 2024年第1期40卷 91-108页

作者： Wen.qin. Xu Sha-sha Wan. Da-chuan Xu Beijin. In.titute for Scien.ific an. En.in.erin. Computin. Beijing University of TechnologyBeijing100124China Departmen. of Mathematics an. Statistics California State UniversityLong BeachCalifornia90840USA Departmen. of Mathematics an. Physics Shijiazhuang Tiedao UniversityShijiazhuang050043China

The classical Archimedean.approximation.of π uses the semiperimeter or area of regular polygon. in.cribed in.or circumscribed about a un.t circle in.R~2 an. it is well-kn.wn.that by usin. lin.ar combin.tion. of these basic estimates,modern.extrapolation.techn.ques can.greatly speed up the approximation.***,when.n.vertices are ran.omly selected on.the circle,the semiperimeter an. area of the correspon.in. ran.om in.cribed an. circumscribin. polygon. are kn.wn.to con.erge to π almost surely as n.∞,an. by further applyin. extrapolation.processes,faster con.ergen.e rates can.also be achieved through similar lin.ar combin.tion. of the semiperimeter an. area of these ran.om *** this paper,we further develop n.n.in.ar extrapolation.methods for approximatin. π through certain.n.n.in.ar fun.tion. of the semiperimeter an. area of such *** focus on.two types of extrapolation.estimates of the forms χ_n.S_n.αA_n.β an. Y_n.p)=(αS_n.p+βA_n.p)~(1/p) where α+β=1,p≠0,an. Sn.an. An.respectively represen.s the semiperimeter an. area of a ran.om n.gon.in.cribed in.the un.t circle in.R~2,an. Xn.may be viewed as the limit of Y_n.p) when.p→*** derivin. probabilistic asymptotic expan.ion. with carefully con.rolled error estimates for Xn.an. Y_n.p),we show that the choice α=4/3,β=-1/3 min.mizes the approximation.error in.both cases,an. their distribution. are also asymptotically n.rmal.

关键词： Archimedean.polygon. ran.om polygon. approximation. ofπ extrapolation.processes asymptotic con.ergen.e

Crystallin.-amorphous M@Mn.x(M=Co,Fe,n.)en.apsulated in.n.trogen.doped carbon.for en.an.ed efficien. an. durable hydrogen.evolution.reaction

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Rare Metals 2024年第4期43卷 1547-1556页

作者： Yan. Yan. Xiao-chuan Duan.Shao-Hui Guo Xian.Min. Zhan. College of Materials Scien.e an. En.in.erin. College of ChemistryKey Laboratory of Interface Science and Engineering in Advanced MaterialsTaiyuan University of TechnologyYuci030600China

Developin. earth-abun.an. electrocatalysts for hydrogen.evolution.reaction.HER)is importan. for the sustain.ble en.rgy ***,efficien. an. stable heterocatalysts con.istin. of crystallin.-amorphous M@Mn.(x)(M=Co,Fe,n.)en.apsulated in.n.doped carbon.layers supported with n.doped graphen. sheets(den.ted as M@Mn.(x)@n.-n.)are syn.hesized by facile hydrothermal reaction.an. n.tridation.*** the n.tridin. process,metal ion. in.M(tzbc)_2(H_(2)O)_4(tzbc=4-(1H-1,2,4-triazol-1-yl)ben.oic acid)complexes are reduced to crystallin. M cores,accompan.ed by the formation.of amorphous Mn.(x)shells;the tzbc ligan.s are in.itu carbon.zed to form outermost n.doped carbon.n.)layers that con.ect with in.er Mn.(x)via M-n.C motifs in.erited from the complex precursors an. in.ibit the tran.ition.of Mn.(x)from amorphous to crystallin. *** Co@Con.(x)@n.-n. catalyst exhibits excellen. HER activity with small overpoten.ials of 45 an. 64 mV at a cathode curren. den.ity of 10 mA·cm^(-2)an. low Tafel slopes of 40 an. 85 mV·dec^(-1)in.0.5 mol·L^(-1)H_(2)SO_4 an.1.0 mol·L^(-1)KOH electrolytes,*** Co@Con.(x)@n.-n. retain. 97%of the in.tial overpoten.ial after 100,000 s in.both acidic an. alkalin. *** outstan.in. HER performan.e origin.tes from the crystallin.-amorphous Co@Con.(x)that redistributes electron. aroun. the heteroin.erfaces,facilitatin. the con.ersion.process of H^(+)/H_(2)O to hydrogen.an. thereby promotin. HER *** outermost n. layers serve as the armor of Co@Con.(x),an. graphen. n.n.sheets act as carriers of egg-like Co@Con.(x)@n. an. con.uction.paths for electron.shuttles,en.urin. stable an. con.in.ous electrocatalytic hydrogen.production.

关键词： Hydrogen.evolution.reaction Electrocatalysts Iron.group metals Heterojun.tion Crystallin.-amorphous structure

Elimin.tion.of methicillin.resistan. Staphylococcus aureus biofilms on.titan.um implan.s via photothermally‑triggered n.tric oxide an. immun.therapy for en.an.ed osseoin.egration

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Military Medical Research 2024年第2期11卷 157-179页

作者： Yon.‑Lin.Yu Jun.Jie Wu chuan‑chuan Lin.Xian.Qin.Fran.lin.R.Tay Li Miao Bai‑Lon. Tao Yan. Jiao Departmen. of Pathology Affiliated Hospital of Zunyi Medical UniversityZunyi 563003GuizhouChina Laboratory Research Cen.er the First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Departmen. of Blood Tran.fusion Laboratory of Radiation Biologythe Second Affiliated HospitalArmy Military Medical UniversityChongqing 400037China Departmen. of Reproductive En.ocrin.logy Chongqing Health Center for Women and ChildrenChongqing 401147China The Graduate School Augusta UniversityAugustaGA 30912USA Departmen. of Stomatology the Seventh Medical Center of PLA General HospitalBeijing 100700China

Backgroun.:Treatmen. of methicillin.resistan. Staphylococcus aureus(MRSA)biofilm in.ection. in.implan. placemen. surgery is limited by the lack of an.imicrobial activity of titan.um(Ti)*** is a n.ed to explore more effective approaches for the treatmen. of MRSA biofilm ***:Herein.an.in.erfacial fun.tion.lization.strategy is proposed by the in.egration.of mesoporous polydopamin. n.n.particles(PDA),n.tric oxide(n.)release don.r sodium n.troprusside(Sn.)an. osteogen.c growth peptide(OGP)on.o Ti implan.s,den.ted as Ti-PDA@*** physical an. chemical properties of Ti-PDA@Sn.-OGP were assessed by scan.in. electron.microscopy,X-ray photoelectron.spectroscope,water con.act an.le,photothermal property an. n. release *** syn.rgistic an.ibacterial effect an. elimin.tion.of the MRSA biofilms were evaluated by 2′,7′-dichlorofluorescein.diacetate probe,1-n.phen.ln.phthylamin. assay,aden.sin. triphosphate in.en.ity,O-n.trophen.l-β-D-galactopyran.side hydrolysis activity,bicin.hon.n.c acid *** stain.n.,assays for alkalin. phosphatase activity,collagen.secretion.an. extracellular matrix min.ralization.quan.itative real‑time reverse tran.cription.polymerase chain.reaction.an. en.yme-lin.ed immun.sorben. assay(ELISA)were used to evaluate the in.lammatory respon.e an. osteogen.c ability in.bon. marrow stromal cells(MSCs),RAW264.7 cells an. their co-culture *** stain.n.,ELISA,micro-CT,hematoxylin.an. eosin.Masson.s trichrome an. immun.histochemistry stain.n. were used to evaluate the eradication.of MRSA biofilms,in.ibition.of in.lammatory respon.e,an. promotion.of osseoin.egration.of Ti-PDA@Sn.-OGP in.***:Ti-PDA@Sn.-OGP displayed a syn.rgistic photothermal an. n.-depen.en. an.ibacterial effect again.t MRSA followin. n.ar-in.rared light(n.R)irradiation.an. effectively elimin.ted the formed MRSA biofilms by in.ucin. reactive oxygen.species(ROS)-mediated oxidative stress,destroyin. bacterial membran. in.egrity an.

关键词： Polydopamin. n.n.particles Methicillin.resistan. Staphylococcus aureus n.tric oxide Osseoin.egration Osteo-immun.modulation Photothermal effect Titan.um implan.s

En.n.ioselective Syn.hesis of Ben.imidazole Atropisomers Featurin. a n.n.Axis

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Chin.se Journ.l of Chemistry 2024年第7期42卷 711-718页

作者： Fan.-Bei Ge Qi-Kun.Yin.chuan-Jun.Lu Xuan.Xuan.Jia Fen. Ren.Ron. Liu College of Chemistry an. Chemical En.in.erin. Qingdao UniversityQingdaoShandong 266071China School of Pharmacy Key Laboratory of Molecular Pharmacology and Drug EvaluationMinistry of EducationYantai UniversityYantaiShandong 264005China

Atroposelective syn.hesis of n.n.atropisomers is an.emergin. area but remain. un.erexplored;in.particular,the syn.hesis of n.n.ben.imidazole atropisomers is still ***,the first en.n.ioselective syn.hesis of n.n.ben.imidazole atropisomers via the palladium-catalyzed de n.vo con.truction.of ben.imidazole skeleton.is *** readily available palladium catalyst an. biphosphin. ligan.,a broad ran.e of n.n.iaryl ben.imidazole an. in.ole-ben.imidazole atropisomers were con.en.en.ly ac-cessed in.high yields an. with excellen. ***,these n.n.ben.imidazole atropisomers showed great an.i-tumor activity an. selectivity to breast can.er MCF-7 *** simple catalytic system,broad substrate scope,high en.n.ioselectivi-ty,an. good bioactivity make this approach highly attractive.

关键词： Asymmetric syn.hesis Atropisomerism Palladium Ben.imidazole An.itumor

n.glycosylation.of Wn.3 regulates the progression.of hepatocellular carcin.ma by affectin. Wn./β-caten.n.sign.l pathway

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World Journ.l of Gastroin.estin.l On.ology 2024年第6期16卷 2769-2780页

作者： Xin.Zhan.Zhan. Xiao-chuan Mo Zhu-Tin. Wan. Ron. Sun.Da-Quan.Sun Departmen. of Biochemistry an. Molecular Biology&Research Cen.er for Basic Medical Scien.es Guizhou Medical UniversityGuiyang 550025Guizhou ProvinceChina

BACKGROUn. Wn./FZD-mediated sign.lin. pathways are activated in.more than.90%of hepatocellular carcin.ma(HCC)cell *** a well-kn.wn.secretory glycoprotein.Wn.3 can.in.eract with FZD receptors on.the cell surface,thereby activatin. the Wn./β-caten.n.sign.lin. ***,the n.glycosylation.modification.site of Wn.3 an. the effect of this modification.on.the biological fun.tion.of the protein.are still *** To in.estigate the effect of Wn.3 n.glycosylation.on.the biological fun.tion.of HCC *** Site-directed mutagen.sis was used to verify the Wn.3 n.glycosylation.sites,actin.mycin.D treatmen. was used to detect the stability of Wn.3 after site-directed mutation.the bin.in. of the n.glycosylation.site-directed mutan. Wn.3 to FZD7 was observed by laser con.ocal microscopy,an. the effects of the n.glycosylation.site-directed mutation.of Wn.3 on.the Wn./β-caten.n.sign.lin. pathway an. the progression.of HCC cells were detected by western.blot an. cell fun.tion.*** Wn.3 has two n.glycosylation.modified sites(Asn.0 an. Asn.01);when.a sin.le site at amin. acid 301 is mutated,the stability of Wn.3 is weaken.d;the bin.in. ability of Wn.3 to FZD7 decreases when.both sites are mutated simultan.ously;an. the level of protein. related to the Wn./β-caten.n.sign.lin. pathway is *** proliferation.migration.an. in.asion.are also weaken.d in.the case of sin.le 301 site an. double-site *** These results in.icate that by in.ibitin. the n.glycosylation.of Wn.3,the proliferation.migration.in.asion.an. colon. formation.abilities of liver can.er cells can.be weaken.d,which might provide n.w therapeutic strategies for clin.cal liver can.er in.the future.

关键词： Wn.3 n.glycosylation Hepatocellular carcin.ma Liver can.er Wn./β-caten.n FZD7

Electron.c structure regulation.an. built-in.electric field syn.rgistically stren.then.photocatalytic n.trogen.fixation.performan.e on.Ti-BiOBr/TiO_(2)heterostructure

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Rare Metals 2024年第3期43卷 1125-1138页

作者： Ru-Qi Li Yu-Jie Bian.Chun.Min. Yan. Li Guo Tao-Xia Ma chuan-Tao Wan. Fen. Fu Dan.Jun.Wan. College of Chemistry an. Chemical En.in.erin. Yan’an UniversityYan’an Key Laboratory of Green Catalysis and Quality Improvement and Utilization of Low Rank CoalYan’an716000China

At presen.,in.ustrial syn.hetic ammon.a was still obtain.d through the Hubble-Bosch process,with large en.rgy *** is a research hotspot to realize green.syn.hetic ammon.a by usin. solar *** difficulty of photocatalytic ammon.a syn.hesis was that the photo-excited electron. have n.t en.ugh en.rgy to active n.*** this study,Ti was doped in.o BiOBr by on.-step hydrothermal method,which was oxidized in.o TiO_(2)when.the dopin. amoun. reaches the maximum,in.situ formin. Ti_(0.31)B_(0.69)OB/TiO_(2)*** from the syn.rgistic effect of Ti dopin. an. S-scheme heterojun.tion.the syn.hetic ammon.a efficien.y of Ti_(0.31)B_(0.69)OB/TiO_(2)-11.96 reached 1.643 mmol·g_(cat)^(-1)at mild con.ition. an. without hole scaven.er for up to 7 h,the efficien.y of syn.hetic ammon.a is 115 times,10.5 times an. 3.3 times of that of BiOBr,Ti_(0.31)B_(0.69)OB an. TiO_(2),***,DFT calculation.con.irms that Ti dopin. accurately refin. the electron.c structure of BiOBr,facilitate n.trogen.adsorption.activation.an. reduce hydrogen.tion.reaction.en.rgy barrier,thus acceleratin. the reaction.kin.tics of photocatalytic n.trogen.reduction.n.R),Mean.hile,con.tructin. S-scheme heterojun.tion.boosts the separation.an. tran.fer of photogen.rated electron.hole pairs,improvin. the reduction.ability of electron. in.the con.uction.ban. of TiO_(2)an. the oxidation.ability of holes in.the valen.e ban. of Ti_(0.31)B_(0.69)OB.

关键词： S-scheme heterostructure Electron.c structure regulation Built-in.electric field Syn.rgistical stren.gthen.n. Photocatalytic n.trogen.fixation