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NEW LABELLING sCHEME OF ROTATION-VIBRATION sTATEs IN A LINEAR POLYATOMIC MOLECuLE-LIE ALGEBRAIC POINT OF VIEW

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分子科学与化学研究 1982年第4期 71-77页

作者：张锦辉潘毓刚 department of chemistry boston college chestnut hill ma 02167 u.s.a.

THE results of a study on Clebsh-Gordan coefficients of polarharmonics have been reported.A labelling scheme has *** the new scheme,some rotation-vibration stateof a molecule will be labelled with *** doesnot mean they have double *** using the concept ofspace-time symmetry and the dynamical symmetry of a doublydegenerate vibration-su(2),the rotation and vibration inmolecular spectroscopy can be treated as one *** realization of Lie group,and can be greatly simplifiedby use of Racah-Wigner algebra,as is done in atomic,nu-clear and molecular electronic spectroscopies.

关键词： NEW LABELLING sCHEME OF ROTATION-VIBRATION sTATEs IN A LINEAR POLYATOMIC MOLECuLE-LIE ALGEBRAIC POINT OF VIEW

How dopants limit the ultrahigh thermal conductivity of boron arsenide:a first principles study

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npj Computational materials 2021年第1期7卷 491-497页

作者： mauro Fava Nakib Haider Protik Chunhua Li Navaneetha Krishnan Ravichandran Jesús Carrete Ambroise van Roekeghem Georg K.H.madsen Natalio Mingo David Broido universitéGrenoble Alpes Saint-Martin-d’HèresFrance John A.Paulson school of Engineering and Applied sciences Harvard UniversityCambridgeMAUSA department of Physics Boston CollegeChestnut HillMAUSA department of Mechanical Engineering Indian Institute of ScienceBangaloreIndia Institute of materials chemistry TU WienViennaAustria CEA LITENGrenobleFrance

The promise enabled by boron arsenide’s(BAs)high thermal conductivity(κ)in power electronics cannot be assessed without taking into account the reduction incurred when doping the *** first principles calculations,we determine theκreduction induced by different group IV impurities in BAs as a function of concentration and charge *** unveil a general trend,where neutral impurities scatter phonons more strongly than the charged *** and GeAs impurities show by far the weakest phonon scattering and retain BAsκvalues of over~1000W⋅K^(−1)⋅m^(−1) even at high *** si and Ge achieve large hole concentrations while maintaining highκ.Furthermore,going beyond the doping compensation threshold associated to Fermi level pinning triggers observable changes in the thermal *** informs design considerations on the doping of BAs,and it also suggests a direct way to determine the onset of compensation doping in experimental samples.

关键词： principles boron scatter

Response patterns of simulated corn yield and soil nitrous oxide emission to precipitation change

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Ecological Processes 2023年第1期12卷 247-259页

作者： Navneet Kaur Dafeng Hui Daniel M.Riccuito Melanie A.mayes Hanqin Tian department of Biological sciences Tennessee State UniversityNashvilleTN 37209USA Environmental sciences Division and Climate Change science Institute Oak Ridge National LaboratoryOak RidgeTNUSA schiller Institute for Integrated science and society Department of Earth and Environmental SciencesBoston CollegeChestnut HillMAUSA

Background Precipitation plays an important role in crop production and soil greenhouse gas ***,how crop yield and soil nitrous oxide(N_(2)O)emission respond to precipitation change,particularly with different background precipitations(dry,normal,and wet years),has not been well *** this study,we examined the impacts of precipitation changes on corn yield and soil N_(2)O emission using a long-term(1981-2020,40 years)climate dataset as well as seven manipulated precipitation treatments with different background precipitations using the DeNitrification-DeComposition(DNDC)*** Results showed large variations of corn yield and precipitation but small variation of soil N_(2)O emission among 40 *** corn yield and soil N_(2)O emission showed near linear relationships with precipitation based on the long-term precipitation data,but with different response patters of corn yield and soil N_(2)O emission to precipitation *** yield showed a positive linear response to precipitation manipulations in the dry year,but no response to increases in precipitation in the normal year,and a trend of decrease in the wet *** extreme drought treatments reduced corn yield sharply in both normal and wet *** contrast,soil N_(2)O emission mostly responded linearly to precipitation *** in precipitation in the dry year reduced more soil N_(2)O emission than those in the normal and wet years,while increases in precipitation increased more soil N_(2)O emission in the normal and wet years than in the dry *** This study revealed different response patterns of corn yield and soil N_(2)O emission to precipitation and highlights that mitigation strategy for soil N_(2)O emission reduction should consider different background climate conditions.

关键词： Background precipitation DNDC model Precipitation change Response pattern Yield soil N_(2)O emission

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Dependence of interface energetics and kinetics on catalyst loading in a photoelectrochemical system

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Nano Research 2019年第9期12卷 2378-2384页

作者： Yumin He srin ivas Vanka Tianyue Gao Da He Jeremy Espano Yanyan Zhao Qi Dong Chaochao Lang Yongjie Wang Thomas W. Hamann Zetian Mi Dunwei Wang department of chemistry Merkert Chemistry CenterBoston College2609 Beacon StreetChestnut HillMassachusetts 02467USA department of Electrical Engineering and Computer science University of Michigan1301 Beal AvenueAnn ArborMichigan 48109USA department of chemistry Michigan State UniversityEast LansingMichigan 48824USA department of Electrical and Computer Engineering McGill University3480 University StreetMontrealQuebecH3A 0E9Canada

solar hydrogen production by the photoelectrochemical method promises a means to store solar *** it is generally understood that the process is highly sensitive to the nature of the interface between the semiconductor and the electrolyte,a detailed understanding of this interface is still *** instance,few prior studies have established a clear relationship between the interface energetics and the catalyst loading *** we aim to study this relationship on a prototypical si-based photoelectrochemical *** types of interfaces were examined,one with GaN nanowires as a protection layer and one *** was found that when GaN was present,higher Pt loading (> 0.1 μg/cm2) led to not only better water reduction (and,hence,hydrogen evolution) kinetics but also more favorable interface energetics for greater *** the absence of the protection layer,by stark contrast,increased Pt loading exhibited no measurable influence on the interface energetics,and the main difference was observed only in the hydrogen evolution *** study sheds new light on the importance of interface engineering for further improvement of photoelectrochemical systems,especially concerning the role of catalysts and protection layers.

关键词： photoelectrochemistry water splitt ing si hydroge n evolutio n catalyst nano wires

Anomalous CDW ground state in Cu_(2)se:A wave-like fluctuation of the dc I-v curve near 50 K

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Journal of materiomics 2017年第2期3卷 150-157页

作者： Mengliang Yao Weishu Liu Xiang Chen Zhensong Ren stephen Wilson Zhifeng Ren Cyril P.Opeil department of Physics Boston CollegeChestnut HillMA 02467USA department of Physics and TcsuH University of HoustonTX 77204USA department of materials University of CaliforniaSanta BarbaraCA 93106USA department of materials science and Engineering Southern University of Science and TechnologyShenzhenGuangdong 518055China

A charge density wave(CDW)ground state is observed in polycrystalline Cu_(2)se below 125 K,which corresponds to an energy gap of 40.9 meV and an electron-phonon coupling constant of *** to the polycrystalline structure,the Peierls transition process has been expanded to a wide temperature range from 90 K to 160 *** Hall carrier concentration shows a continuous decrease from 2.1×10^(20)to 1.6×10^(20)cm^(-3)in the temperature range from 160 K to 90 K,while almost unchanged above 160 K and below 90 *** entering the CDW ground state,a wave-like fluctuation was observed in theI-Vcurve near 50 K,which exhibits a periodic negative differential resistivity in an applied electric field due to the *** also investigated the doping effect of Zn,Ni,and Te on the CDWground *** Zn and Ni doped Cu_(2)se show a CDW character with increased energy gap and electron-phonon coupling constant,but no notable Peierls transition was observed in Te doped Cu_(2)*** wave-likeI-Vcurve was also seen in Cu_(1.98)Zn_(0.02)se near 40 *** regular fluctuation in the dcI-Vcurve was not magnetic field sensitive,but temperature and sample size sensitive.

关键词： Peierls transition CDW dc I-V curve Wave-like fluctuation Copper selenide

PREDICTION OF WATER AROuND POLAR PROTEIN sIDE CHAINs:AN AID TO sTRuCTuRE REFINEMENT

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PREDICTION OF WATER AROUND POLAR PROTEIN SIDE CHAINS:AN AID ...

Direct observation of Pt nanocrystal coalescence induced by electron-excitation-enhanced van der Waals interactions

sixteenth Congress of the International union of Crystallography

作者： s.M.Roe M.M.Teeter The Nitrogen Fixation Lab The University of SussexBrightonBN1 9RQEngland department of chemistry Boston CollegeChestnut HillMA 02167.USA

＜正＞Water is important in stabilizing the folded conformation of a protein and also is necessary for enzyme *** inclusion in a crystallographic model can be beneficial during refinement or understanding the mechanism of enzyme *** have analyzed the patterns in hydration of polar side chains around crambin and 6 other proteins which diffract to bettter than 1.4A

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Nano Research 2014年第3期7卷 308-314页

作者： Ying Jiang Yong Wang Yu Yang Zhang Zhengfei Zhang Wentao Yuan Chenghua sun Xiao Wei Casey N. Brodsky Chia-Kuang Tsung Jixue Li Xiaofeng Zhang scott X. mao shengbai Zhang Ze Zhang Center of Electron Microscopy and state Key Laboratory of silicon materials Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China department of Physics Applied Physics and Astronomy Rensselaer Polytechnic Institute Troy New York 12180 USA Centre for Computational Molecular science Australian Institute for Bioengineering and Nanotechnology University of Queensland St Lucia QLD 4072 Australia department of chemistry Boston College Chestnut Hill MA 02467 USA Hitachi High Technologies America Pleasanton CA 94588 USA department of Mechanical Engineering and materials science University of Pittsburgh Pittsburgh PA 15261 USA

Nanocrystal coalescence has attracted paramount attention in nanostructure fabrication in the past decades. Tremendous endeavor and progress have been made in understanding its mechanisms, benefiting from the development of transmission electron microscopy. However, many mechanisms still remain unclear, especially for nanocrystals that lack a permanent dipole moment standing on a solid substrate. Here, we report an in situ coalescence of Pt nanocrystals on an amorphous carbon substrate induced by electron-excitation- enhanced van der Waals interactions studied by transmission electron microscopy and first principles calculations. It is found that the electron-beam-induced excitation can significantly enhance the van der Waals interaction between Pt nanocrystals and reduce the binding energy between Pt nanocrystals and the carbon substrate, both of which promote the coalescence. This work extends our understanding of the nanocrystal coalescence observed in a transmission electron microscope and sheds light on a potential pathway toward practical electron- beam-controlled nanofabrication.

关键词： Pt nanocrystals coalescence electron excitation van der Waals interactions

Chiral flux phase in the Kagome superconductor AV_(3)sb_(5)

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science Bulletin 2021年第14期66卷 1384-1388,M0003页

作者： Xilin Feng Kun Jiang Ziqiang Wang Jiangping Hu Beijing National Laboratory for Condensed matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China school of Physical sciences University of Chinese Academy of SciencesBeijing 100190China department of Physics Boston CollegeChestnut HillMA 02467USA Kavli Institute of Theoretical sciences University of Chinese Academy of SciencesBeijing 100190China

We argue that the topological charge density wave phase in the quasi-2D Kagome superconductor AV3sb5 is a chiral flux *** the symmetry of the Kagome lattice,we show that the chiral flux phase has the lowest energy among those states which exhibit 2×2 charge orders observed *** state breaks the time-reversal symmetry and displays anomalous Hall *** explicit pattern of the density of state in real space is *** results are supported by recent experiments and suggest that these materials are new platforms to investigate the interplay between topology,superconductivity and electron–electron correlations.

关键词： Kagome superconductor Charge density wave Time-reversal symmetry breaking Chiral flux phase

A flexible adhesive with a conductivity of 5240 s/cm

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science Bulletin 2021年第7期66卷 657-660,M0003页

作者： Dongwei Zhang sai Liu Yue Jiang Yuxin Yin Zhengjie Xu Xiangyu Kong Guofu Zhou Jun-Ming Liu Krzysztof Kempa Liming Ding Jinwei Gao Guangdong Provincial Key Laboratory of Optical Information materials and Technology Academy of Advanced OptoelectronicsSouth China Normal UniversityGuangzhou 510006China Laboratory of solid state Microstructures Nanjing UniversityNanjing 210093China department of Physics Boston CollegeChestnut Hill MA 02467USA Center for Excellence in Nanoscience(CAs) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing WO 190China Guangdong Provincial Engineering Technology Research Center for Transparent Conductive materials Guangzhou 510006China

Conductive adhesives(CAs)providing reliable connectionsbetween electronic *** been widely used in solarcells[1],light emitting diodes(LED5)[2],radio frequency compo-nents[3],and printed&wearable ***.[4-6].Basically,CAs are mainly composed of conductive fillers and resin,whichgive the *** *** the conductive path,respectively[7].Among conductive fillers with high conductivity,such as carbon materials[7,8].and metals[4,5.9.10],are the keycomponent[9,10],determining the feature and cost of the CAs.

关键词：导电银胶柔性薄膜光滑表面渗流阈值导电介质电导率导电网络高电导