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Applying image clustering to phylogenetic analysis:A trial

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Plant Diversity 2023年第2期45卷 234-237页

作者： Li-Dan Tao Wei-Bang Sun Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences 100049 BeijingChina Kunming Botanical Garden Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China

Phylogenetic studies have increased in recent years,largely due to rapid developments in sequencing techniques (Tucker et al.,2017).However,molecular phylogenetic studies rely on collecting biomaterials,which limits t... 详细信息

关键词： image biomaterials limits

Explosion limits estimation and process optimization of direct propylene epoxidation with H2 and O2

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Chinese Journal of Chemical Engineering 2019年第12期27卷 2968-2978页

作者： Mengke Lu Yanqiang Tang Wenyao Chen Guanghua Ye Gang Qian Xuezhi Duan Weikang Yuan Xinggui Zhou State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China

Direct propylene epoxidation with H2 and O2,an attractive process to produce propylene oxide(PO),has a potential explosion danger due to the coexistence of flammable gases(i.e.,C3 H6 and H2)and oxidizer(i.e.,O2).The unknown explosion limits of the multi-component feed gas mixture make it difficult to optimize the reaction process under safe operation conditions.In this work,a distribution method is proposed and verified to be effective by comparing estimated and experimental explosion limits of more than 200 kinds of flammable gas mixture.Then,it is employed to estimate the explosion limits of the feed gas mixture,some results of which are also validated by the classic Le Chatelier’s Rule and flammable resistance method.Based on the estimated explosion limits,process optimization is carried out using commercially high and inherently safe reactant concentrations to enhance reaction performance.The promising results are directly obtained through the interface called gOPT in gPROMS only by using a simple,easy-constructed and mature packed-bed reactor,such as the PO yield of 13.3%,PO selectivity of 85.1%and outlet PO fraction of 1.8%.These results can be rationalized by indepth analyses and discussion about the effects of the decision variables on the operation safety and reaction performance.The insights revealed here could shed new light on the process development of the PO production based on the estimation of the explosion limits of the multi-component feed gas mixture containing flammable gase s,inert gas and O2,followed by process optimization.

关键词： Direct propylene epoxidation with H2/O2 Propylene oxide Safe operation Explosion limits estimation Process optimization

Continuity of functors with respect to generalized inductive limits

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Frontiers of Mathematics in China 2019年第3期14卷 551-566页

作者： Jiajie HUA Xiaochun FANG Xiao-Ming XU School of Mathematics Physics and Information Engineering Jiaxing University Jiaxing 314001 China Department of Mathematics Tongji University Shanghai 200092 China School of Science Shanghai Institute of Technology Shanghai 201418 China

Let(Ai,φi,i+1) be a generalized indue Live system of a sequeiiee (Ai) of unital separable C^*-algebras,with A =limi→∞(Ai,φi,i+1). Set φj,i=φi-1,i^0…0φj+1,j+2^0 φj,j+1 for all i>j. We prove that if φj,i are order zero completely positive contractions for all j and i>j, And L:=inf{λ|λ∈σ(φj,i(1Aj)) for all j uud i>j}>0, where σ(φj,i(1Aj)) is the speetrum of φj,i(1Aj),than limi→∞(Cu(Ai),Cu((φi,i+1))=Cu(A), where Cu(A) is a stable version of the Cuntz semigroup of C^*-algebra A. Let (An,φm,n) be a generalized inductive syfitem of C^*-algahrafl, with the ipmkn order zero completely positive contractions. We also prove that if the decomposition rank (nuclear dimension) of ,4n is no more t han some integer k for each n, then the decompostition rank (nuclear dimension) of A is also no more than k.

关键词： Completely positive map order zero generalized inductive limits classification of C^*-algebra

Periodic Wave Solutions and Their limits for the Modified Kd V–KP Equations

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Acta Mathematica Sinica,English Series 2015年第6期31卷 1043-1056页

作者： Ming SONG Zheng Rong LIU Chen Xi YANG Department of Mathematics Shaoxing University Department of Mathematics Yuxi Normal University Department of Mathematics South China University of Technology

In this paper, we use the bifurcation method of dynamical systems to study the periodic wave solutions and their limits for the modified KdV-KP equations. Some explicit periodic wave solutions are obtained. These solutions contain smooth periodic wave solutions and periodic blow-up solutions. Their limits contain solitary wave solutions, periodic wave solutions, kink wave solutions and unbounded solutions.

关键词： Bifurcation method modified KdV-KP equation periodic wave solutions limits

Steel Design by Advanced Analysis: Material Modeling and Strain limits

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Engineering 2019年第2期5卷 243-249页

作者： Leroy Gardner Xiang Yun Andreas Fieber Lorenzo Macorini Department of Civil and Environmental Engineering Imperial College London London SW7 2AZ UK

Structural analysis of steel frames is typically performed using beam elements. Since these elements are unable to explicitly capture the local buckling behavior of steel cross-sections, traditional steel design specifications use the concept of cross-section classification to determine the extent to which the strength and deformation capacity of a cross-section are affected by local buckling. The use of plastic design methods are restricted to Class 1 cross-sections, which possess sufficient rotation capacity for plastic hinges to develop and a collapse mechanism to form. Local buckling prevents the development of plastic hinges with such rotation capacity for cross-sections of higher classes and, unless computationally demanding shell elements are used, elastic analysis is required. However, this article demonstrates that local buckling can be mimicked effectively in beam elements by incorporating the continuous strength method (CSM) strain limits into the analysis. Furthermore, by performing an advanced analysis that accounts for both geometric and material nonlinearities, no additional design checks are required. The positive influence of the strain hardening observed in stocky cross-sections can also be harnessed, provided a suitably accurate stress–strain relationship is adopted;a quad-linear material model for hot-rolled steels is described for this purpose. The CSM strain limits allow cross-sections of all slenderness to be analyzed in a consistent advanced analysis framework and to benefit from the appropriate level of load redistribution. The proposed approach is applied herein to individual members, continuous beams, and frames, and is shown to bring significant benefits in terms of accuracy and consistency over current steel design specifications.

关键词： Advanced analysis Continuous strength method Local buckling Material modeling Strain limits

Adiabatic limits,vanishing theorems and the noncommutative residue

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Science China Mathematics 2009年第12期52卷 2699-2713页

作者： LIU KeFeng WANG Yong Center of Mathematical Sciences Zhejiang UniversityHangzhou 310027China Department of Mathematics University of California at Los AngelesLos AngelesCA 90095-1555USA School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024China

In this paper,we compute the adiabatic limit of the scalar curvature and prove several vanishing theorems by taking adiabatic limits.As an application,we give a Kastler-Kalau-Walze type theorem for foliations.

关键词： foliations adiabatic limits vanishing theorems noncommutative residue

Health Phys.Abstracts,Volume 124,Number 5

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辐射防护 2023年第4期43卷 384-387页

Aligning Exposure limits for Contact Currents with Exposure limits for Electric Fields Robert Kavet1 and Richard A.Tell2(1.Kavet Consulting LLC,4455 Worden Way,Oakland,CA 94619;2.Richard Tell Associates,Inc.,10037 Long Meadow Road,Madison,AL 35756.)Abstract:The Institute for Electrical and Electronic Engineers(IEEE)and the International Commission on Non-ionizing Radiation Protection(ICNIRP)have established limits for exposures to electromagnetic fields across the 0-300 GHz(non-ionizing)spectrum,including limits on contact currents(CC)specified by IEEE for 0-110 MHz(ICNIRP issued a CC“guidance level”).

关键词： specified limits Number

limits of physical properties and design for GBBL capacitors of semiconducting ceramics

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Chinese Science Bulletin 1995年第6期40卷 463-466页

作者：郑振华陈羽缪容之 Department of Physics Ningbo University Ningbo 315211 China

Grain boundary barrier layer （GBBL） capacitors are widely used for their excellent physical properties. But since the invention of BaTiO3 GBBL capacitor in the 1960s, no theory can quantitatively describe their physical properties, which has resulted in many problems in the design and manufacture of GBBL capacitors. In this note, on the basis of grain-boundary-barrier model, we quantitatively analyze the physical properties and their limits of GBBL capacitors, and thus make designs and study the methods to improve the properties of GBBL capacitors.

关键词： semiconducting ceramics GBBL capacitors limits of physical properties design of device.

Static voltage stability analysis with limits of generators

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Journal of Harbin Institute of Technology(New Series) 2000年第4期7卷 7-11页

作者：包黎昕段献忠何仰赞 Dep. of Electri. Eng. Huazhong Univ. of Sci. Wuhan 430074 China

Presents the equations established for the reactive power output of generators varying with terminal voltage with field and stator current limits taken into consideration, from which an algorithm is developed for calculation of power flow, and the static voltage stability analysis conducted by combining this algorithm with the continuous power flow method, and the comparison of simulation results with those obtained with fixed reactive power limits.

关键词： voltage stability voltage collapse power flow limits