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Rapid sensitive fluorescence detection of cadmium(Ⅱ)with pyrene excimer switching aptasensor

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Journal of Environmental Sciences 2023年第11期133卷 1-7页

作者： Hao Yu qiang Zhao State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 310000China

Heavy metal cadmium(Ⅱ)contamination often occurs,causing great health risk to human due to high toxicity of cadmium(Ⅱ).Rapid,sensitive and simple detection of cadmium(Ⅱ)are of great importance in environmental *** advantage of aptamer in specific recognition,easy modification,and capability of binding-induced structure change,here we reported a simple fluorescent sensor with rapid and sensitive response for Cd^(2+)using aptamer pyrene excimer *** aptamer was labeled with dual pyrene molecules at two ends of the *** binding of Cd^(2+)to this aptamer probe brought the pyrene labels into close proximity and enhanced formation of a pyrene excimer,which generated increased fluorescence at 485 *** measuring the fluorescence of pyrene excimer,we achieved detection of Cd^(2+)with this *** the optimum experimental conditions,the detection limit of Cd^(2+)reached nanomolar *** method was selective and allowed for the detection of Cd^(2+)in tap *** fluorescence aptasensor is promising for rapid detection of Cd^(2+)in broad applications.

关键词： Aptamer Cadmium Pyrene excimer Fluorescence Sensor

A Local Statistical Structural Model for Amorphous Solids

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Chinese Physics Letters 2013年第12期30卷 87-90页

作者： SUN qiang Key Laboratory of Orogenic Belts and Crustal Evolution(Ministry of Education) School of Earth and Planetary SciencesPeking UniversityBeijing 100871

From Raman spectroscopic study on OH stretching bands,the local statistical interpretation for water structure is *** to the closely structural relationship between amorphous solids and liquids,the structural model is extended to investigate the amorphous solids,which indicates that various intensity of potential can be expected around an atom(molecule).From this,a local statistical order parameter is proposed to understand the short-range order and long-range *** order parameter is influenced by the cooling rate in the glass formation,which means that glass is formed with a slower cooling rate,and has higher structural *** amorphous solids,the geometric topology is closely related to chemical bonding type,such as covalent bond and metallic bond.

关键词： amorphous solids structural

The Fixed Subgroups of Homeomorphisms of Seifert Manifolds

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Acta Mathematica Sinica,English Series 2015年第5期31卷 797-810页

作者： qiang ZHANG School of Mathematics and Statistics Xi'an Jiaotong University

Let M be a compact connected orientable Seifert manifold with hyperbolic orbifold BM, and fπ ： π1 （M）→π1 （M） be an automorphism induced by an orientation-reversing homeomorphism f of M. We give a bound on the rank of the fixed subgroup of fπ, namely, rankFix（fπ）〈 2rankπ1（M）, which is an analogue of inequalities on surface groups and hyperbolic 3-manifold groups.

关键词： Seifert manifolds fixed subgroups homeomorphisms

Spontaneous Infection and Periodic Evolving of Domain in a Diffusive SIS Epidemic Model

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 164-191页

作者： qiang Wen Guo-qiang Ren Bin Liu School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan430074China

In this paper, we consider a susceptible-infective-susceptible(SIS) reaction-diffusion epidemic model with spontaneous infection and logistic source in a periodically evolving domain. Using the iterative technique,the uniform boundedness of solution is established. In addition, the spatial-temporal risk index R0(ρ) depending on the domain evolution rate ρ(t) as well as its analytical properties are discussed. The monotonicity of R0(ρ)with respect to the diffusion coefficients of the infected dI, the spontaneous infection rate η(ρ(t)y) and interval length L is investigated under appropriate conditions. Further, the existence and asymptotic behavior of periodic endemic equilibria are explored by upper and lower solution method. Finally, some numerical simulations are presented to illustrate our analytical results. Our results provide valuable information for disease control and prevention.

关键词： diffusive SIS model spontaneous infection periodically evolving domain periodic endemic equilibrium

A Description of Fixed Subgroups of Free Groups

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Chinese Annals of Mathematics,Series B 2016年第5期37卷 713-718页

作者： qiang ZHANG School of Mathematics and Statistics Xi’an Jiaotong University

Let F be a finitely generated free group. Martino and Ventura gave an explicit description for the fixed subgroups of automorphisms of F. The author generalizes their results to injective endomorphisms.

关键词： subgroups Fixed finitely automorphism explicit trivial isomorphic invariant integers argument

Anisotropic and nonlinear metasurface for multiple functions

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Science China(Information Sciences) 2021年第9期64卷 165-174页

作者： Zhangjie LUO Xueyao REN qiang WANG qiang CHENG Tiejun CUI State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast University Pazhou Lab Air and Missile Defense College Air Force Engineering University

We present a novel anisotropic and nonlinear metasurface integrated with multiple functions of diffuse scattering, beam splitting, and normal reflection, which can be switched in real time by tuning the polarization state or power level of the incident microwave. The key lies in the two judiciously designed anisotropic nonlinear particles in subwavelength scales that possess opposite reflection phases under one polarization and the same nonlinear power-dependent reflection phases under the orthogonal polarization. These properties are demonstrated comprehensively via comparisons between their reflection responses, receiving abilities, and nonlinear circuitry behaviors. In addition, both the spatial arrangement and the electrically enabling strategy of the particles are underpinned to pursue the proposed functions, which are verified through numerical simulations and measurements. When the metasurface is illuminated by plane waves coming from the direction perpendicular to it, a significant beam splitting effect is achieved with strong x-polarized incidence,which is switched to a specular reflection when the incoming power decreases. Under y-polarization,a diffuse scattering phenomenon is obtained, which is not dependent on the incident intensity. The study is expected to offer new solutions to many electromagnetic scenarios involving energy transmissions and protections.

关键词： multi-function metasurface nonlinear anisotropic polarization

Embeddings Among Quantum Affine sl_(n)

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Acta Mathematica Sinica,English Series 2024年第3期40卷 792-805页

作者： Yi qiang LI Department of Mathematics University at BuffaloThe State University of New YorkBuffaloNY 14260USA

We establish an explicit embedding of a quantum affine sl_(n) into a quantum affine sl_(n)+*** embedding serves as a common generalization of two natural,but seemingly unrelated,embed-dings,one on the quantum affine Schur algebra level and the other on the non-quantum *** embedding on the quantum affine Schur algebras is used extensively in the analysis of canonical bases of quantum affine sln and gl_(n).The embedding on the non-quantum level is used crucially in a work of Riche and Williamson on the study of modular representation theory of general linear groups over a finite *** same embedding is also used in a work of Maksimau on the categorical representations of affine general linear *** further provide a more natural compatibility statement of the em-bedding on the idempotent version with that on the quantum affine Schur algebra level.A gl_(n)-variant of the embedding is also established.

关键词： Quantum affine sl_(n) embeddings

A p-version embedded model for simulation of concrete temperature fields with cooling pipes

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Water Science and Engineering 2015年第3期8卷 248-256页

作者： Sheng qiang Zhi-qiang Xie Rui Zhong College of Water Conservancy and Hydropower Engineering Hohai University Lyles School of Civil Engineering Purdue University Department of Material and Structure Changjiang River Scientific Research Institute School of Engineering University of Connecticut

Pipe cooling is an effective method of mass concrete temperature control, but its accurate and convenient numerical simulation is still a cumbersome problem. An improved embedded model, considering the water temperature variation along the pipe, was proposed for simulating the temperature field of early-age concrete structures containing cooling pipes. The improved model was verified with an engineering example. Then, the p-version self-adaption algorithm for the improved embedded model was deduced, and the initial values and boundary conditions were examined. Comparison of some numerical samples shows that the proposed model can provide satisfying precision and a higher efficiency. The analysis efficiency can be doubled at the same precision, even for a large-scale element. The p-version algorithm can fit grids of different sizes for the temperature field simulation. The convenience of the proposed algorithm lies in the possibility of locating more pipe segments in one element without the need of so regular a shape as in the explicit model.

关键词： Concrete temperature field Cooling pipe Embedded model p-version Numerical simulation

Juvenile hormone signaling-a mini review

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Insect Science 2019年第4期26卷 600-606页

作者： Kang Li qiang-qiang Jia Sheng Li Guangzhou Key Laboratory of Insect Development Regulation and Application Research Institute of Insect Science and Technology&School of Life SciencesSouth China Normal UniversityGuangzhouChina

Since it was first postulated by Wigglesworth in 1934, juvenile hormone (JH) is considered a status quo hormone in insects because it prevents metamorphosis that is initiated by the molting hormone 20-hydroxyecdysone (20E). During the last decade, significant advances have been made regarding JH signaling. First, the bHLH-PAS transcription factor Met/Gce was identified as the JH intracellular receptor. In the presence of JH, with the assistance of Hsp83, and through physical association with a bHLH?PAS transcriptional co-activator, Met/Gce enters the nucleus and binds to E-box-like motifs in promoter regions of JH primary?response genes for inducing gene expression. Second, the zinc finger transcription factor Kr-hl was identified as the anti-metamorphic factor which transduces JH signaling. Via Kr-hl binding sites, Kr-hl represses expression of 20E primary?response genes (i.e. Bi\ E93 and E5) to prevent 20E-induced metamorphosis. Third, through the intracellular signaling, JH promotes differ ent aspects of female reproduction. Nevertheless, this action varies greatly from species to species. Last, a hypothetical JH membrane receptor has been predicted to be either a GPCR or a tyrosine kinase receptor. In future, it will be a great challenge to understand how the JH intracellular receptor Met/Gce and the yet unidentified JH membrane receptor coordinate to regulate metamorphosis and reproduction in insects.

关键词： intracellular receptor juvenile hormone (JH) Kr-h 1 membrane receptor Met/Gce metamorphosis reproduction