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point process microstructural model of metallic thin films with implications for coarsening

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npj computational materials 2023年第1期9卷 2074-2082页

作者： J.m.Rickman K.Barmak Y.Epshteyn c.Liu Department of materials science and Engineering Lehigh UniversityBethlehemPA 18015USA Department of physics Lehigh UniversityBethlehemPA 18015USA Department of Applied physics and Applied mathematics Columbia UniversityNew YorkNY 10027USA Department of mathematics The University of UtahSalt Lake CityUT 84112USA Department of Applied mathematics Illinois Institute of TechnologyChicagoIL 60616USA

We develop a thin-film microstructural model that represents structural markers(i.e.,triple junctions in the two-dimensional projections of the structure of films with columnar grains)in terms of a stochastic,marked point process and the microstructure itself in terms of a grain-boundary *** advantage of this representation is that it is conveniently applicable to the characterization of microstructures obtained from crystal orientation mapping,leading to a picture of an ensemble of interacting triple junctions,while providing results that inform grain-growth models with experimental *** specifically,calculated quantities such as pair,partial pair and mark correlation functions,along with the microstructural mutual information(entropy),highlight effective triple junction interactions that dictate microstructural *** validate this approach,we characterize microstructures from Al thin films via crystal orientation mapping and formulate an approach,akin to classical density functional theory,to describe grain growth that embodies triple-junction interactions.

关键词： grain microstructure process

Near Earth Vortices Driving of Field Aligned currents Based on magnetosphere multiscale and swarm Observations

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空间科学学报 2019年第1期39卷 9-17页

作者： ZHANG c sHEN c YANG Y Y DuNLOp m W TI s RussELL c T LüHR H BuRcH J L LINDQVIsT p A TORBERT R B FRIIs-cHRIsTENsEN E state Key Laboratory of space Weather National Space Science Center college of Earth science University of Chinese Academy of Sciences college of science Harbin Institute of Technology Institute of china seismological Bureau Crustal Stress space science Institute School of Astronautics Beihang University Rutherford Appleton Laboratory university of california German Research center For Geosciences German Research Center for Geosciences southwest Research Institute Royal Institute of Technology university of New Hampshire Danish National space center

A long-standing mystery in the study of Field-Aligned currents(FAcs) has been that: how the currents are generated and why they appear to be much stronger at high altitudes than in the ionosphere. Here we present two events of magnetotail FAcs observed by the magnetospheric multiscale spacecraft(mms) on 1 st July and 14 th July 2016, to show how the substorm current Wedges(scW) were formed. The results show that particles were transferred heading towards the Earth during the expansion phase of *** azimuthal flow formed clockwise(counter-clockwise) vortex-like motion, and then generated downward(upward) FAcs on the tailward/poleward side of the distorted field with opposite vorticity on their Earthward/equatorward side. We also analyzed the Region 1 FAcs observed by the Earth Explorer swarm spacecraft on 1 st July 2016 and found that they were associated with FAcs observed by mms, although differing by a factor of 10. This difference suggests that either there was the closure of the currents at altitudes above 500 km or the currents were not strictly parallel to B and closed at longitudes away from where they were generated.

关键词： substorm current wedge magnetosphere Field-aligned currents Flow vorticity multiple spacecraft measurements

Anomalous transport of light at the phase transition to localization:strong dependence with incident angle

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光子学研究：英文版 2018年第10期6卷 929-942页

作者： ERNEsTO JImENEZ-VILLAR m.c.s.XAVIER NIKLAus u.WETTER VALDEcI mEsTRE WELITON s.mARTINs GABRIEL F.BAssO V.A.ERmAKOV F.c.mARQuEs GILBERTO F.DE sA Instituto de pesquisas Energeticas e Nucleares CNEN_IPENSao PauloSP 05508-000Brazil Departamento de Ffsica Universidade Federal da ParaibaJoao PessoaPB 58051-970Brazil Departamento de Fisica Universidade Estadual da ParaibaArarunaPB 58233-000Brazil ccEA Universidade Estadual da ParaibaPatosPB 58706-560Brazil Departamento de Fisica Universidade Federal Rural de PernambucoRecifePE 52171-900Brazil Departamento de Informatica Universidade Federal da ParaibaJoao PessoaPB 58055-000Brazil Departamento de Fisica Aplicada Universidade Estadual de CampinasCampinasSP 13083-859Brazil Quimica Fundamental Universidade Federal de PernambucoRecifePE 50670-901Brazil

There has been a growing interest in disordered optical media in recent years due to their potential applications in solar collectors, random lasers, light confinement, and other advanced photonic functions. This paper studies the transport of light for different incidence angles in a strongly disordered optical medium composed of core-shell TiO_2@silica nanoparticles suspended in an ethanol solution. A decrease of optical conductance and an increase of absorption near the input border are reported when the incidence angle increases. The specular reflection, measured for the photons that enter the sample, is lower than the effective internal reflection undergone by the coherently backscattered photons in the exact opposite direction, indicating a nonreciprocal propagation of *** study represents a novel approach in order to understand the complex physics involved at the phase transition to localization.

关键词：光学介质太阳能通讯技术发展现状

Towards critical and supercritical electromagnetic fields

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High power Laser science and Engineering 2023年第2期11卷 26-36页

作者： m.marklund T.G.Blackburn A.Gonoskov J.magnusson s.s.Bulanov A.Ilderton Department of physics University of GothenburgGothenburgSweden Lawrence Berkeley National Laboratory BerkeleyCaliforniaUSA Higgs centre School of Physics and AstronomyUniversity of EdinburghEdinburghUK

The availability of ever stronger,laser-generated electromagnetic fields underpins continuing progress in the study and application of nonlinear phenomena in basic physical systems,ranging from molecules and atoms to relativistic plasmas and quantum *** raises the question:how far will we be able to go with future lasers?One exciting prospect is the attainment of field strengths approaching the schwinger critical field Ecr in the laboratory frame,such that the field invariant E^(2)−c^(2)B^(2)>E_(cr)^(2) is *** feasibility of doing so has been questioned,on the basis that cascade generation of dense electron–positron plasma would inevitably lead to absorption or screening of the incident *** we discuss the potential for future lasers to overcome such obstacles,by combining the concept of multiple colliding laser pulses with that of frequency upshifting via a tailored laser–plasma *** compresses the electromagnetic field energy into a region of nanometre size and attosecond duration,which increases the field magnitude at fixed power but also suppresses pair *** results indicate that laser facilities with peak power of tens of pW could be capable of reaching *** a scenario opens up prospects for the experimental investigation of phenomena previously considered to occur only in the most extreme environments in the universe.

关键词： schwinger effect advanced focusing concepts attosecond pulses dipole wave surface high-order harmonic generation

Amberlyst-15 catalyzed synthesis of alkyl/aryl/heterocyclic phosphonates

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chinese chemical Letters 2011年第8期22卷 895-898页

作者： u.m.Rao Kunda V.N.Reddy mudumala c.s.Reddy Gangireddy B.R.Nemallapudi K.N.sandip s.R.cirandur Department of chemistry Sri Venkateswara UniversityTirupati 517502.India Bio-Organic Division BARCMumbaiIndia

A novel and efficient procedure for the synthesis of alkyl phosphonates through one pot condensation of alkyl halide and trialkyl /aryl phosphite in the presence of Amberlyst-15 as catalyst under solvent free conditions was *** demonstrated several advantages such as good yields of products,simple operation,convenient separation and inexpensive catalyst.

关键词： Dialkyl/aryl alkyl phosphonates Amberlyst-15

Occurrence and fate of endogenous steroid hormones,alkylphenol ethoxylates, bisphenol A and phthalates in municipal sewage treatment systems

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Journal of Environmental sciences 2017年第11期29卷 49-58页

作者： Qian Wu James c.W.Lam Karen Y.Kwok mirabelle m.p.Tsui paul K.s.Lam state Key Laboratory in marine pollution (sKLmp) Department of Biology and Chemistry Research Centre for the Oceans and Human Health Shenzhen Key Laboratory for Sustainable Use of Marine Biodiversity City University of Hong Kong Department of science and Environmental studies The Education University of Hong of Kong

steroid hormones, alkylphenol ethoxylates（ApEOs） and phthalic acid esters（pAEs） are emerging endocrine disrupting chemicals（EDcs） that can interfere with the endocrine function in organisms at low concentrations. The occurrence, distribution behavior, removal rate and the fate of 31 target EDcs in sewage treatment plants, which consist of various treatment facilities and receiving water in Hong Kong, were investigated. Estrone,nonylphenol-di-ethoxylate and diethyl phthalate were found to be dominant in each group of influent samples with concentrations ranging from 11–33, 747–3945 and 445–4635 ng/L,respectively. conversely, progesterone, nonylphenol-mono-ethoxylate and bis（2-ethylhexyl）phthalate were the most abundant in dewatered sludge, with concentrations ranging from 0.9–237, 75–19,743 and 4310–37,016 ng/g（dry weight）. The removal rates of primary sedimentation and disinfection approaches were lower than 30% for most of the chemicals,while those of activated sludge and reverse osmosis were greater than 80% for more than two-thirds of the compounds, noticeably decreasing the estrogenic risk of sewage discharged into the environment. steroid hormones were removed via biological degradation, while some ApEOs and pAEs adsorbed to the sludge. Victoria Harbor poses a low to medium estrogenic risk mainly contributed by estrone and estradiol and deserves attention.

关键词： Endocrine disruptor steroid hormone Alkylphenol ethoxylate phthalic acid ester Risk assessment

Arm psA-certified IoT chip security: A case study

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Tsinghua science and Technology 2023年第2期28卷 244-257页

作者： Fei chen Duming Luo Jianqiang Li Victor c.m.Leung shiqi Li Junfeng Fan college of computer science and software Engineering Shenzhen UniversityShenzhen 518060China Department of Electrical and computer Engineering the University of British ColumbiaVancouverBC V6T 1Z4Canada Open security Research Inc.Shenzhen 518000China

With the large scale adoption of Internet of Things(IoT)applications in people’s lives and industrial manufacturing processes,IoT security has become an important problem *** security significantly relies on the security of the underlying hardware chip,which often contains critical information,such as encryption *** understand existing IoT chip security,this study analyzes the security of an IoT security chip that has obtained an Arm platform security Architecture(psA)Level 2 *** analysis shows that the chip leaks part of the encryption key and presents a considerable security ***,we use commodity equipment to collect electromagnetic traces of the *** a statistical T-test,we find that the target chip has physical leakage during the AEs encryption *** further use correlation analysis to locate the detailed encryption interval in the collected electromagnetic trace for the Advanced Encryption standard(AEs)encryption *** the basis of the intermediate value correlation analysis,we recover half of the 16-byte AEs encryption *** repeat the process for three different tests;in all the tests,we obtain the same result,and we recover around 8 bytes of the 16-byte AEs encryption ***,experimental results indicate that despite the Arm psA Level 2 certification,the target security chip still suffers from physical *** layer application developers should impose strong security mechanisms in addition to those of the chip itself to ensure IoT application security.

关键词： Internet of Things(IoT)security chip Arm platform security Architecture(psA)certification electromagnetic side-channel attack Advanced Encryption standard(AEs)encryption key leakage

chemical, isotopic and amino acid composition of mukundpura cm2.0(cm1) chondrite: Evidence of parent body aqueous alteration

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Geoscience Frontiers 2019年第2期10卷 495-504页

作者： N.G.Rudraswami A.K.Naik R.p.Tripathi N.BhANDari s.G.Karapurkar m.shyam prasad E.V.s.s.K.Babu u.V.R.Vijaya sarathi National Institute of Oceanography (council of scientific and Industrial Research) 78 BGKT Extension science and spirituality Research Institute National Geophysical Research Institute (council of scientific and Industrial Research) Indian Institute of chemical Technology (council of scientific and Industrial Research)

The carbonaceous chondrites are intriguing and unique in the sense that they are the only rocks that provide pristine records of the early solar nebular processes. We report here results of a detailed mineralogical, chemical, amino acid and isotopic studies of a recently observed fall at mukundpura, near Jaipur in Rajasthan, India. Abundance of olivines in this meteorite is low and of serpentine minerals is high. FeO/siO_2 = 1.05 in its poorly characterized phases(pcp) is similar to that observed in other cm2.0 chondrites. The water content of ～9.8 wt.% is similar to that found in many other cm *** examination of matrix shows that its terrestrial weathering grade is WO but aqueous parent body alteration is high, as reflected in low abundance of identifiable chondrules and abundant remnants of chondrules(～7%). Thus, most of the chondrules formed initially have been significantly altered or dissolved by aqueous alterations on their parent bodies. The measured bulk carbon(2.3%) and nitrogen content and their isotopic(δ^(13)c =-5.5‰, δ^(15)N = 23.6%0) composition is consistent with cm2.0 classification probably bordering cm1. several amino acids such as Alanine, serine, proline, Valine, Threonine,Leucine, Isoleucine, Asparagine and Histamine are present. Tyrosine and Tryptophan may occur in trace amounts which could not be precisely determined. All these data show that mukundpura chondrite lies at the boundary of cm2.0 and cm1 type carbonaceous chondrites making it one of the most primitive chondrites.

关键词： carbonaceous chondrite mukundpura cm Isotope Amino acid

Observation of a highly conductive warm dense state of water with ultrafast pump–probe freeelectron-laser measurements

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matter and Radiation at Extremes 2021年第5期6卷 1-12页

作者： Z.chen X.Na c.B.curry s.Liang m.French A.Descamps D.p.Deponte J.D.Koralek J.B.Kim s.Lebovitz m.Nakatsutsumi B.K.Ofori-Okai R.Redmer c.Roedel m.schörner s.skruszewicz p.sperling s.Toleikis m.Z.mo s.H.Glenzer sLAc National Accelerator Laboratory Menlo ParkCalifornia 94025USA university of Alberta EdmontonAlberta T6G 1H9Canada Institute of physics University of RostockD-18051 RostockGermany Aeronautics and Astronautics Department Stanford UniversityStanfordCalifornia 94305USA Northwestern university EvanstonIllinois 60208USA European XFEL 22869 SchenefeldGermany Friedrich schiller university Jena 07743 JenaGermany Technical university Darmstadt 64289 DarmstadtGermany Deutsches Elektronen-synchrotron DEsY 22607 HamburgGermany

The electrical conductivity of water under extreme temperatures and densities plays a central role in modeling planetary magnetic *** data are vital to test theories of high-energy-densitywater and assess the possible development and presence of extraterrestrial *** states are also important in biology and chemistry studies when specimens in water are confined and excited using ultrafast optical or free-electron lasers(FELs).Here we utilize femtosecond optical lasers to measure the transient reflection and transmission of ultrathin water sheet samples uniformly heated by a 13.6 nm FEL approaching a highly conducting state at electron temperatures exceeding 20000 *** experiment probes the trajectory ofwater through the high-energy-density phase space and provides insights into changes in the index of refraction,charge carrier densities,andAcelectrical conductivity at optical *** excitation energy densities exceeding 10mJ/kg,the index of refraction falls to n0.7,and the thermally excited free-carrier density reaches ne531027 m−3,which is over an order of magnitude higher than that of the electron carriers produced by direct *** specular reflection is observed owing to critical electron density shielding of electromagnetic *** optical conductivity reaches 23104 s/m,a value that is one to two orders of magnitude lower than those of simplemetals in a liquid *** electron temperatures below 15000 K,the experimental results agreewell with the theoretical calculations using density-functional theory/molecular-dynamics *** increasing temperature,the electron density increases and the system approaches a Fermi *** this regime,the conductivities agree better with predictions from the Ziman theory of liquid metals.

关键词： pump exceeding state