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differences between amorphous indium oxide thin films

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Progress in Natural Science:Materials International 2013年第5期23卷 475-480页

作者： d.Bruce Buchholz Li Zeng Michael J.Bedzyk Robert P.H.chang department of Materials Science and Engineering Northwestern University

A series of 60~nm thick indium oxide thin-films,all amorphous as determined by x-ray diffraction,were found to have physical and electrical properties that depended on the temperature of *** carrier mobility and flm conductivity decreased with decreasing deposition temperature;the best electrical properties of high mobility and conductivity were observed at a deposition temperature just below the temperature at which crystalline films *** density of the flm also decreased with deposition temperature from 7.2g/cm3 at+50℃ to 5.3g/cm3 at 100℃.

关键词： Transparent conducting oxide Semiconductor Oxide Amorphous deposition temperature

Strictosidine synthase,an indispensable enzyme involved in the biosynthesis of terpenoid indole andβ-carboline alkaloids

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Chinese Journal of Natural Medicines 2021年第8期19卷 591-607页

作者： CAO Ning WANG chang-Hong The MOE Key Laboratory for Standardization of Chinese Medicines Shanghai R&D Centre for Standardization of Chinese MedicinesInstitute of Chinese Materia MedicaShanghai University of Traditional Chinese MedicineShanghai 201203China

Terpenoid indole(TIAs)andβ-carboline alkaloids(BCAs),such as suppressant reserpine,vasodilatory yohimbine,and antimalarial quinine,are natural compounds derived from *** compounds can exert powerful pharmacological effects but be obtained from limited source in *** whole biosynthetic pathway of TIAs and BCAs,The Pictet–Spengler reaction catalyzed by strictosidine synthase(STR;EC:4.***.3.2)is the rate-limiting ***,it is necessary to investigate their biosynthesis pathways,especially the role of STR,and related findings will support the biosynthetic generation of natural and unnatural *** review summarizes the latest studies concerning the function of STR in TIA and BCA biosynthesis,and illustrates the compounds derived from *** substrate specificity of STR based on its structure is also *** that contain sixbladed four-strandedβ-propeller folds in many organisms,other than plants,are *** presence of these folds may lead to similar functions among *** expression of STR gene can greatly influence the production of many *** is mainly applied to product various valuable drugs in plant cell suspension culture and biosynthesis in other carriers.

关键词： Biosynthesis Pictet-Spengler reaction β-Carboline alkaloids Strictosidine synthase Terpenoid indole

On the α-spectra of Uniform Hypergraphs and Its Associated Graphs

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Acta Mathematica Sinica,English Series 2020年第7期36卷 842-850页

作者： Yuan HOU An chang Chao SHI department of Computer Engineering Fuzhou University Zhicheng CollegeFuzhou 350000P.R.China Center for discrete Mathematics and Theoretical Computer Science Fuzhou UniversityFuzhou 350000P.R.China School of Mathematical Sciences Xiamen UniversityXiamen 361000P.R.China

For 0 ≤α < 1 and a k-uniform hypergraph H, the tensor Aα(H) associated with H is defined as Aα(H) = αd(H) +(1-α)A(H), where d(H) and A(H) are the diagonal tensor of degrees and the adjacency tensor of H, respect... 详细信息

For 0 ≤α d a k-uniform hypergraph H, the tensor Aα(H) associated with H is defined as Aα(H) = αd(H) +(1-α)A(H), where d(H) and A(H) are the diagonal tensor of degrees and the adjacency tensor of H, respectively. The α-spectra of H is the set of all eigenvalues of Aα(H) and the α-spectral radius ρα(H) is the largest modulus of the elements in the spectrum of Aα(H). In this paper we define the line graph L(H) of a uniform hypergraph H and prove that ρα(H) ≤■ρα(L(H)) + 1 + α(Δ-1-δ*/k), where Δ and δ* are the maximum degree of H and the minimum degree of L(H), respectively. We also generalize some results on α-spectra of Gk,s, which is obtained from G by blowing up each vertex into an s-set and each edge into a k-set where 1 ≤ s ≤ k/2.

关键词： tensor spectra Uniform

Eight decades of compositional change in a managed northern hardwood landscape

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Forest Ecosystems 2023年第3期10卷 398-410页

作者： Mark J.ducey olivia L.Fraser Mariko Yamasaki Ethan P.Belair William B.Leak University of New Hampshire Department of Natural Resources and the Environment114 James HallDurhamNH03824USA U.S.d.A.Forest Service White Mountain National Forest71 White Mountain DriveCamptonNH03223USA U.S.d.A.Forest Service Northern Research Station271 Mast RoadDurhamNH03824USA The Nature Conservancy Natural Climate SolutionsAfrica Regional Portland Office45 Exchange StSuite 303PortlandME04101USA

We analyzed over 8 decades of change in forest composition(represented by species proportion of basal area)and size class from more than 400 permanent plots located on the Bartlett Experimental Forest in the White Mountains of New *** data represent one of the longest-term landscape-scale records of forest change based on permanent plots in North *** analyzed the plots based on elevation class,land type indicating assumed successional direction(grouped into coniferous and deciduous),and inventory period within managed and unmanaged portions of the *** ongoing shift from small-to large-diameter stems is clear across all species,in response to the overall aging of the forest following exploitative harvesting in the 19th *** compositional changes include a continuing decline in shade-intolerant species(paper birch and aspen),along with the mid-tolerant yellow *** increase in red maple abundance through the early 1990s has leveled off or *** shade-tolerant species,increases in beech and red spruce were largely consistent with assumed land type on unmanaged plots,but heavy marking against diseased beech on managed plots restricted increase of that *** maple declined in abundance except where silvicultural intervention helped maintain *** contrast,eastern hemlock showed a continuing expansion at all elevations below 600 *** data continue to show little or no evidence of upward migration of species,despite evidence of recent regional change in ***,the BEF is poised for substantial changes when emerald ash borer and hemlock woolly adelgid,both of which are known to infest nearby areas,do arrive.

关键词： Northern hardwoods Succession Stand dynamics Silviculture

Level structure of the double-shell closure system with Z=14 and N=20:^(34)Si

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Chinese Physics C 2022年第12期46卷 226-231页

作者： chang-Bum Moon Cenxi Yuan Center for Exotic Nuclear Studies The Institute for Basic Science(IBS)Daejeon 34126Republic of Korea Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China

The level structure of the double-magic nucleus ^(34)Si(Z=14,N=20)was investigated by evaluating the available *** the basis of experimental results from the beta-decay and fusion-evaporation reactions,we established the level scheme by assigning spin-parities up to 6_(1)^(+)at 6233 *** high energy positions of the excited states are consistent with the magicity at ^(34)Si,such as the 2_(2)^(+)state of the spherical ground band at 4.519 MeV and the 3^(-),4^(-),and 5^(-)states of the one-particle one-hole cross-shell states at approximately 4.5 *** nucleus,for a long time,has attracted much attention because of,on one side,a proton bubble structure in the ground state and,on the other side,a deformation in the second 0^(+)state,0_(2)^(+).By a comparison of the constructed level scheme with the shell model calculations,we describe the emerging structures in the ground and second 0+states and the negative-parity 3^(-)states within the framework of the shell model *** propose a deformed rotational band with the cascading 6_(2)^(+)−4_(1)^(+)−2_(1)^(+)transitions built on the 0_(2)^(+)state.

关键词： double shell closure level scheme two particle-two hole excitations large-scale shell model calculations

Integral domains Whose ω-Integral Closures Are Krull domains

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Algebra Colloquium 2020年第2期27卷 287-298页

作者： Gyu Whan chang HwanKoo Kim department of Mathematics Education Incheon National University Incheon 22012Korea division of Computer and Information Engineering Hoseo University Asan 31499Korea

Let d be an integral domain with quotient field K,d be the integral closure of d in K,and d^[w] be the ω-integral closure of d in K;so d ■ d^[w],and equality holds when d is Noetherian or dim(d)=*** Mori-Nagata theorem states that if d is Noetherian,then d is a Krull domain;it has also been investigated when d is a dedekind *** study integral domains d such that d^[w] is a Krull *** also provide an example of an integral domain d such that d ■ d ■ d^[w],t-dim(d)=1,d is a Priifer multiplication domain with v-dim(d)=2,and d^[w] is a UFd.

关键词： Krull domain ω-integral closure PvMd t-Nagata ring weakly dedekind domain

In-Plane Semi-Linear Cloaks with Arbitrary Shape

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Acta Mechanica Solida Sinica 2019年第3期32卷 277-286页

作者： dengke Guo Zheng chang Gengkai Hu Key Laboratory of dynamics and Control of Flight Vehicle Ministry of Education School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China College of Science China Agricultural University Beijing 100083 China

Soft materials with semi-linear strain energy function can be used as smart transformation media to manipulate elastic waves via finite pre-deformation. However, the intrinsic cons train ts involved in such materials limit the shapes of t ransformation devices to very sim - pie cases. In this work, combining theoretical and numerical analyses, we report an approach of achieving the in-plane elastodynamic cloak with arbitrary shape. We demonstrate that with the appropriate out-of^plane st retch applied on the semi-linear material, cloaking effec t can be achieved for both P- and SV-waves in the symmetrie plane of a 3d domain, and the performance of the cloak with arbitrary cross section can be guaranteed for relatively small in-plane rot at ion. In addition, we propose an empirical formula to predic t the deformation limit of the cloaks with semi-linear materials. This work may stimulate the experimental research on softmatter- based transformation devices. Potential applications can be anticipated in nondestructive testing, structure impact protection, biomedical imaging and soft robotics.

关键词： Elastic waves Cloak Hyperelasticity Semi-linear Arbitrary shape

Influence of Co Content on Raman and Photoluminescence Spectra of Co doped ZnO Nanowires

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Journal of Materials Science & Technology 2012年第4期28卷 313-316页

作者： Y.Q. chang P.W. Wang S.L. Ni Y. Long X.d. Li School of Materials Science anti Engineering University of Science and Technology Beijing Beijing 100083 China department of Physics National Key Laboratory of Mesoscopic Physics Peking University Beijing 100871 China

Co doped ZnO nanowires with different Co contents have been fabricated by a chemical vapor deposition method. X-ray diffraction results show that all the samples are of single phase and crystallize in wurtzite ZnO structure. The lattice parameter a increases with increasing Co content, while the parameter c has no obvious change with increasing Co. Raman spectra show that the nonpolar E2（High） mode becomes broad and weak with the doping of Co, which indicates that the incorporation of Co causes structural disorder in the crystalline columnar ZnO lattice. The photolurninescence spectra exhibit that the position of the ultraviolet emission shifts to short wavelength and the intensity decreases with increasing Co. The green emission is affected by two contrary factors. It is increased by the introduced defects, but suppressed by the interaction between Co doping and native defects and the later affects it more significantly.

关键词： Co doped ZnO nanowires Raman Photoluminescence Single phase

On the CR Poincaré–Lelong Equation, Yamabe Steady Solitons and Structures of Complete Noncompact Sasakian Manifolds

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Acta Mathematica Sinica,English Series 2018年第8期34卷 1313-1344页

作者： der Chen chang Shu Cheng chang Ying Bo HAN Chien LIN department of Mathematics and Statistics Georgetown University Washington D. C. 20057 USA Graduate Institute of Applied Science and Engineering Fu Jen Catholic University Taipei 242 Taiwan China Yau Mathematical Sciences Center Tsinghua University Beijing 100084 P. R. China School of Mathematics and Statistics Xinyang Normal University Xinyang 464000 P. R. China department of Mathematics National Tsing Hua University Hsinchu 30013 Taiwan China

In this paper, we solve the so-called CR Poincare-Lelong equation by solving the CR Poisson equation on a complete noncompact CR （2n ＋ 1）-manifold with nonegative pseudohermitian bisectional curvature tensors and vanishing torsion which is an odd dimensional counterpart of Kahler geometry. With applications of this solution plus the CR Liouvelle property, we study the structures of complete noncompact Sasakian manifolds and CR Yamabe steady solitons.

关键词： CR Poisson equation CR Poincare-Lelong equation CR Yamabe solitons