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On B(5,20)2-Groups

Algebra Colloquium 2024年第3期31卷 429-440页

作者： E.A.Alhassan Y.l.tan Y.li School of Mathematical Sciences Jiangsu UniversityZhenjiangJiangsu 212013China Department of Mathematics Brock UniversitySt.CatharinesOntario L2S 3A1Canada

A finite group G is said to be a B(n,k)group if for any n-element subset[a_(1),…,a_(n)]of G,|{a_(i)a_(j)|1≤i,j≤n}|≤*** is of interest to characterize the structure of B(n,k)groups for n(n+1)/2≤k≤n^(2)-*** B(5,k)groups for 15≤k≤19 have been investigated by several *** this paper,we give a complete characterization of B(5,20)2-groups by showing there are five classes of such groups which are nontrivial and nonabelian.

关键词： B(n,k)groups small squaring property central extension GAP

Creep-induced redistribution of alloying elements in CZ1 zirconium alloys

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Journal of Materials Science & technology 2024年第6期173卷 31-44页

作者： W.t.lin Q.Y.lv D.Jiao l.B.Zhang J.tan G.Sha J.Hu China Nuclear Power technology Research Institute Shenzhen 518026China School of Material Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China

Introducing minor alloying elements is an effective strategy to improve the corrosion and mechanical properties of zirconium alloys for nuclear *** in-reactor service,external environment and stress can affect the distribution of alloying elements,substantially changing the degradation process of zirconium *** date,there is a lack of in-depth understanding of the interaction between creep and microchemistry ***,we conducted systematic transmission electron microscopy(tEM)and atom probe tomography(APt)investigations to address creep-induced redistribution of alloying elements in CZ1(Zr-Sn-Nb-Fe-Cr-Cu)zirconium alloy with different initial ***,Fe,Sn,and Cu are found to co-segregate at grain *** higher the intermediate annealing temperature,the larger the Gibbsian interfacial excesses of solute elements *** further demonstrate that creep can reduce the excess value of Fe at grain boundaries due to the coarsening of Zr-Fe-Cr second phase particles via grain boundary and dislocation pipe *** the same time,the excess value of Sn is increased by diffusing from the matrix to grain ***,Cu as a minor element in the concentration range of 0.05-0.3 wt.%is found to segregate at dislocations to form the Cottrell atmosphere and develop Cu-rich nanoclusters for suppressing dislocation *** new understanding of the segregation and clustering of minor alloying elements provides guidance for developing zirconium alloys with enhanced creep resistance.

关键词： Zirconium alloy thermal creep Grain boundary segregation Dislocation segregation Cu-rich nanoclusters

the Consistency of lSE Estimators in Partial linear Regression Models under Mixing Random Errors

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1244-1272页

作者： Yun Bao YAO Yu tan lÜ Chao lU Wei WANG Xue Jun WANG School of Mathematical Sciences Anhui UniversityHefei 230601P.R.China School of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000P.R.China School of Big Data and Statistics Anhui UniversityHefei 230601P.R.China

In this paper,we consider the partial linear regression model y_(i)=x_(i)β^(*)+g(ti)+ε_(i),i=1,2,...,n,where(x_(i),ti)are known fixed design points,g(·)is an unknown function,andβ^(*)is an unknown parameter to be estimated,random errorsε_(i)are(α,β)-mix_(i)ng random *** p-th(p>1)mean consistency,strong consistency and complete consistency for least squares estimators ofβ^(*)and g(·)are investigated under some mild *** addition,a numerical simulation is carried out to study the finite sample performance of the theoretical ***,a real data analysis is provided to further verify the effect of the model.

关键词： (α,β)-mixing random variables partial linear regression model least squares estimator consistency

An Improved Method for Approximating the Infinite-Horizon Value Function of the Discrete-time Switched lQR Problem

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Journal of Systems Science & Complexity 2024年第1期37卷 22-39页

作者： HOU tan lI Yuanlong lIN Zongli Department of Automation Shanghai Jiao Tong UniversityShanghai 200240China Key laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China Shanghai Engineering Research Center of Intelligent Control and Management Shanghai 200240China Charles l.Brown Department of Electrical and Computer Engineering University of VirginiaCharlottesvilleVA 22904-4743USA

this paper considers the problem of approximating the infinite-horizon value function of the discrete-time switched lQR *** particular,the authors propose a new value iteration method to generate a sequence of monotonically decreasing functions that converges exponentially to the value *** method facilitates us to use coarse approximations resulting from faster but less accurate algorithms for further value iteration,and thus,the proposed approach is capable of achieving a better approximation for a given computation time compared with the existing *** numerical examples are presented in this paper to illustrate the effectiveness of the proposed method.

关键词： Optimal control switched linear systems switched lQR problem.

Recent Advances in Catalytic Carbonylation Reactions in Alternative Reaction Media

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Chinese Journal of Chemistry 2024年第4期42卷 406-429页

作者： Csaba Árvai lászló t.Mika Department of Chemical and Environmental Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformylation(oxo-synthesis or Roelen reaction)and the Reppe-reaction,the transition metal-catalyzed carbonylation reactions,providing versatile,facile,and even atom-economic methods for the selective incorporation of C=O functionality to various skeletons,have gained tremendous importance in synthetic organic chemistry from laboratories to industrial *** carbonylation of carbon-carbon multiple bonds,aromatic halides,triflates,etc.,in the presence of various nucleophiles has led the way to produce aldehydes,carboxylic acids,esters,amides,etc.,in the fine chemical ***,these protocols usually proceed in conventional,fossil-based,and usually toxic reaction ***,several attempts have been directed to developing efficient carbonylation methods in alternative,less harmful,non-fossil-based and even in renewable reaction *** this review,we overview the recent applications of alternative solvents such as water,biomass-based alcohols,γ-valerolactone(GVl),2-methyltetrahydrofuran(2-MetHF),ionic liquids(Ils),deep eutectic solvents(DES),alkyl levulinates,limonene,α-pinene,and dimethyl carbonate as well as fluorous media to improve efficiency,safety and environmentally benign nature of carbonylation protocols.

关键词： Carbonylation Catalysis Solvents Green chemistry Carbon monoxide transition metals Homogeneous catalysis Palladium

Electrical characteristics of a fractional-order 3×n Fan network

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Communications in theoretical Physics 2024年第4期76卷 176-187页

作者： Zhi-Zhong tan Xin Wang Department of Physics Nantong UniversityNantong 226019China

In this article a new achievement of fractional-order 3×n Fan networks is *** the first step,the Rt-I method is used to derive the general formulae of the equivalent impedance of fractional-order 3×n Fan *** the second part,the effects of five system parameters(l,C,n,α and β)on amplitude-frequency and phase-frequency characteristics are *** the same time,the amplitude-frequency and phase-frequency characteristics of the fractional order 3×n Fan network are revealed by Matlab *** work has important theoretical and practical significance for resistor network models in the field of natural science and engineering technology.

关键词： fractional-order circuit amplitude-frequency characteristics phase-frequency characteristics Rt-V theory

Nonlinear-Optical Analogies in Nuclear-like Soliton Reactions:Selection Rules,Nonlinear tunneling and Sub-Barrier Fusion–Fission

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Chinese Physics letters 2024年第8期41卷 1-7页

作者： t.l.Belyaeva V.N.Serkin Universidad Autonoma del Estado de Mexico Av.Instituto Literario 100C.P.50000TolucaMexico Benemerita Universidad Autonoma de Puebla Av.4 Sur 104C.P.72001PueblaMexico

the main goal of our study is to reveal unexpected but intriguing analogies arising between optical solitons and nuclear physics,which still remain hidden from *** consider the main cornerstones of the concept of nonlinear optics of nuclear reactions and the well-dressed repulsive-core *** the base of this model,we reveal the most intriguing properties of the nonlinear tunneling of nucleus-like solitons and the soliton selfinduced sub-barrier transparency *** describe novel interesting and stimulating analogies between the interaction of nucleus-like solitons on the repulsive barrier and nuclear sub-barrier *** main finding of this study concerns the conservation of total number of nucleons(or the baryon number)in nuclear-like soliton *** show that inelastic interactions among well-dressed repulsive-core solitons arise only when a“cloud”of“dressing”spectral side-bands appears in the frequency spectra of the *** property of nucleus-like solitons is directly related to the nuclear density distribution described by the dimensionless small shape-squareness *** the Fourier spectra of nucleus-like solitons are similar to the nuclear form *** show that the nuclear-like reactions between well-dressed solitons are realized by“exchange”between“particle-like”side bands in their spectra.

关键词： solitons soliton Nonlinear

Hydrochemical insights on the signatures and genesis of water resources in a high-altitude city on the Qinghai-Xizang Plateau, South-west China

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 123-140页

作者： Jiutan liu Kexin lou Zongjun Gao Menghan tan College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Water resources have crucial implications for the steady development of the urban social *** study investigated the hydrochemical signatures and genesis of water resources in the urban area of lhasa City(UAlC).to this end,several analyses,such as ion ratio analysis and correlation analysis,were performed by comprehensively applying mathematical statistics and integrated hydrochemical *** results show relatively low concentrations of major ions in the groundwater and surface water(GSW)of the *** primary anions and cations are HCO3-and Ca2+,reflecting the HCOg-Ca water ***,groundwater exhibits higher concentrations of key chemical components compared to surface *** are weakly alkaline,with pH values of 7.78 and 7.61,respectively,and they have low salinity with average concentrations of total dissolved solids being 190.74 and 112.17 mg/l,*** inputs have minimal influence on the hydrochemical features of GSw,whereas rock weathering is the dominant controlling ***,cation *** a significant *** influencing their hydrochemical *** to the isotope analysis(H and 180),the primary source of recharge for GSW is atmospheric precipitation,with some input from melted ice and ***,GSW samples from the UAlC show relatively similar 2H and 18O isotopic compositions,indicating the existence of a discernible hydraulic connection linking the two water *** research findings can serve as a valuable scientific reference and foundation for the sustainable development,effective utilization,and proper safeguarding of regional water resources in high-altitude areas.

关键词： Groundwater and surface water Hydrochemical features Genesis mechanism Water quality Urban area of lhasa City

A review of whole-medical systems and holistic care approach for type 2 diabetes and associated metabolic syndrome

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Journal of Integrative Medicine 2024年第3期22卷 199-209页

作者： loveness Makoni Idah t.Manduna Alaisa l.Mbiriri Department of Health Sciences Faculty of Health and Environmental Health SciencesCentral University of TechnologyFree State20 President Brand StreetPrivate bag X20539Bloemfontein 9300South Africa Centre for Applied Food Sustainability and Biotechnology(CAFSaB) Faculty of Health and Environmental Health SciencesCentral University of TechnologyFree State20 President Brand StreetPrivate bag X20539Bloemfontein 9300South Africa Adventist Development and Relief Agency(ADRA) 5 Cecil RoadGreendaleHarare 0000Zimbabwe

Whole-person care and holistic care approach has been proposed for complementary and integrative health care for type 2 diabetes ***,some doubts still exist on the feasibility of replicating processes followed in clinical trials and observational studies in real-world *** narrative literature review summarized and assessed existing clinical evidence(clinical trials,observational studies,and case reports)describing holistic and integrated care approach in adult and adolescent individuals with type 2 diabetes mellitus in clinical *** goal was to highlight existing evidence for implementation and outcomes of whole-medical systems and holistic integrated care approach for type 2 diabetes mellitus.A nonsystematic literature search was performed on Google Scholar,PubMed,Web of Science,ProQuest and ScienceDirect to identify clinical evidence from different parts of the world,evaluating the use of whole-medical systems and/or holistic care interventions in clinical practice for management of type 2 diabetes *** keywords were used in the *** were analyzed using content analysis and simple descriptive statistics(percentages).Most of the studies(64%)were mainly conducted in Eastern countries(India,China and Israel)while 36%of the studies were conducted in the Western countries(USA,Netherlands,Canada and Mexico).lifestyle medicine and integrated naturopathy were shown to be the commonly used whole-medical systems for type 2 diabetes mellitus *** improvements in type 2 diabetes parameters,medication use,other symptoms,and overall feeling of wellness were observed in all *** review study revealed limited utilization and/or documentation of whole-medical systems or holistic care treatments for type 2 diabetes mellitus in regions of the world other than eastern *** medicine,naturopathy,yoga,Ayurveda and traditional Chinese medicine were shown to be effective for type 2 diabetes mellitu

关键词： Complementary and alternative medicine Holistic care Integrative medicine type 2 diabetes mellitus team-based intervention