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Every Sub-Riemannian Manifold Is the Gromov–Hausdorff Limit of a Sequence Riemannian Manifolds

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Acta Mathematica Sinica,English Series 2017年第11期33卷 1565-1568页

作者： Yong Hong HUANG School of Mathematical Science Capital Normal UniversityBeijing 100048P.R.China qiannan preschool education college for nationalities Guiding County of Guizhou Province558000P.R.China

In this paper, we will show that every sub-Riemannian manifold is the Gromov-Hausdorff limit of a sequence of Riemannian manifolds.

关键词： Riemannian manifold Sub-Riemannian manifold Gromov-Hausdorff convergence

Validity of extracting photoionization time delay from the first moment of streaking spectrogram

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Chinese Physics B 2019年第1期28卷 330-339页

作者： Chang-Li Wei Xi Zhao School of Physics and Electronics qiannan Normal college for nationalities Department of Physics Kansas State University

Photoionization time delays have been studied in many streaking experiments in which an attosecond pulse is used to ionize the atomic or solid state target in the presence of a dressing infrared laser field. Among the methods of extracting the time delay from the streaking spectrogram, the simplest one is to calculate the first moment of the spectrogram and to measure its offset relative to the vector potential of the infrared field. The first moment method has been used in many theoretical simulations and analysis of experimental data, but the meaning of this offset needs to be investigated. We simulate the spectrograms and compare the extracted time delay from the first moment with the input Wigner delay. In this study, we show that the first moment method is valid only when the group delay dispersions corresponding to both the spectral phase of the attosecond pulse and the phase of the single-photon transition dipole matrix element of the target are small. Under such circumstance, the electron wave packet behaves like a classical particle and the extracted time delay can be related to a group delay in the photoionization process. To avoid ambiguity and confusion, we also suggest that the photoionization time delay be replaced by photoionization group delay and the Wigner time delay be replaced by Wigner group delay.

关键词： photoionization time delay strong laser field attosecond science first moment

A Scheme for Spin Manipulation in a Quantum Dot with Both Charge and Spin Bias

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Communications in Theoretical Physics 2011年第2期55卷 359-361页

作者：赵华张小伟蔡托周光辉 Department of Physics and Electronics Qiannan Normal College for Nationalities Department of Physics Hunan Normal University

We propose a scheme for the effective polarization and manipulation of electron spin by using a quantum dot with both charge and spin bias. Using the equation of motion for Keldysh nonequilibrium Green function, we study the spin accumulation and polarization for the system. Through analytical analysis and a few numerical examples, it is demonstrated that fairly large spin accumulation and polarization can be produced due to the breaking symmetry of the chemical potential for different electron spin in the leads. Moreover, the direction and the strength of the spin polarization can be conveniently controlled and tuned by varying the charge bias or the gate voltage.

关键词： quantum dot spin bias spin polarization nonequilibrium Green function

The transcription factor CsS40 negatively regulates TCS1 expression and caffeine biosynthesis in connection to leaf senescence in Camellia sinensis

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Horticulture Research 2023年第9期10卷 194-206页

作者： Xinzhuan Yao Hufang Chen Antao Ai Fen Wang Shanshan Lian Hu Tang Yihe Jiang Yujie Jiao Yumei He Tong Li Litang Lu college of Tea Sciences Institute of Plant Health&MedicineThe Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region(Ministry of Education)Guizhou UniversityGuiyang 550025China School of Biological Science and Agriculture Qiannan Normal University for NationalitiesDuyun 558000China

Caffeine is considered as one of the most important bioactive components in the popular plant beverages tea,cacao,and coffee,but as a wide-spread plant secondary metabolite its biosynthetic regulation at transcription level remains largely ***,we report a novel transcription factor Camellia sinensis Senescnece 40(CsS40)as a caffeine biosynthesis regulator,which was discovered during screening a yeast expression library constructed from tea leaf cDNAs for activation of tea caffeine synthase(TCS1)*** multiple hits of the non-self-activation CsS40 clones that bound to and activated TCS1 promoter in yeast-one-hybrid assays,a split-luciferase complementation assay demonstrated that CsS40 acts as a transcription factor to activate the CsTCS1 gene and EMSA assay also demonstrated that CsS40 bound to the TCS1 gene ***,immunofluorescence data indicated that CsS40-GFP fusion was localized in the nuclei of tobacco epidermal *** expression pattern of CsS40 in‘Fuding Dabai’developing leaves was opposite to that of TCS1;and knockdown and overexpression of CsS40 in tea leaf calli significantly increased and decreased TCS1 expression levels,*** expression levels of CsS40 were also negatively correlated to caffeine accumulation in developing leaves and transgenic calli of‘Fuding Dabai’.Furthermore,overexpression of CsS40 reduced the accumulation of xanthine and hypoxanthine in tobacco plants,meanwhile,increased their susceptibility to ***40 expression in tea leaves was also induced by senescence-promoting hormones and environmental *** together,we showed that a novel senescence-related factor CsS40 negatively regulates TCS1 and represses caffeine accumulation in tea cultivar‘Fuding Dabai’.The study provides new insights into caffeine biosynthesis regulation by a plant-specific senescence regulator in tea plants in connection to leaf senescence and hormone signaling.

关键词： S40 caffeine TCS

Highly emissive tribenzotriquinacene-based double-rimed nanocube

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Nano Research 2023年第7期16卷 9584-9590页

作者： Zhilong Jiang Zihao Wu Jun Wang Bangtang Chen Min Wang Weiya Liu Wenzhi Lv Rui Miao He Zhao Die Liu Shenghua Chen Mingzhao Chen Pingshan Wang Institute of Environmental Research at Greater Bay Area Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006China Department of Organic and Polymer Chemistry College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China Department of Chemistry Tsinghua UniversityBeijing 100084China college of Chemistry and Chemical Engineering Qiannan Normal University for NationalitiesDuyun 558000China

The study of discrete nanosized cages has gone a long way to seek aesthetically appealing structures and to carry out functional *** the construction of supramolecular cages via a bottom-up self-assembly process has been well developed,the sophisticated synthesis still remains a *** we report the design and assembly of a giant double-rimed nanocube Zn_(24)LH_(8),built with 8 tribenzotriquinacene as six-connected vertices and 24(tpy=terpyridine)connectivities serving as the *** the single-crystal structure of tribenzotriquinacene-based ligand LH,the bowl-shaped ligand defines a suitable rigid platform for the spatially well-defined attachment of three sets of parallel vertices,which promotes the quantitative formation of the desired three-dimensional(3D)double-rimed cubic *** formed nanocube Zn_(24)LH_(8)possesses molecular weight up to 25.6 kDa and side length 5.3 ***,the Zn_(24)LH_(8)exhibits strong cyan light emission with high luminescence quantum yields in solution and in the solid state based on the inherent cage-confinement induced emission *** adding orange-emissive Rhodamine B,emission tuning experiments were achieved including white light *** work presents a new system for the imitation of complex assemblies and provides a promising candidate for emissive materials.

关键词： self-assembly double-rimed nanocube terpyridine coordination light-emitting metallacages

An algorithm for solving satisfiability problem based on the structural information of formulas

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Frontiers of Computer Science 2021年第6期15卷 191-193页

作者： Zaijun ZHANG Daoyun XU Jincheng ZHOU college of Computer Science and Technology Guizhou UniversityGuiyang 550025China Key Laboratory of Complex Systems and Intelligent Computing and School of Mathematics and Statistics Qiannan Normal University for NationalitiesDuyun 558000China School of Computer and Information Qiannan Normal University for NationalitiesDuyun 558000China

1 Introduction The propositional satisfiability(SAT)problem is an important and prototypical NP-hard problem in theoretical computer science[1].Many efforts have been made for designing high-performance SAT *** existing practical techniques for solving SAT problems are mainly divided into two categories:complete search technique and stochastic local search technique.

关键词： satisfiability technique computer

HeTDSE:A GPU based program to solve the full-dimensional time-dependent Schr?dinger equation for two-electron helium subjected to strong laser fields

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Chinese Physics B 2021年第7期30卷 216-225页

作者： Xi Zhao Gangtai Zhang Tingting Bai Jun Wang Wei-Wei Yu School of Physics and Information Technology Shaanxi Normal UniversityXi'an 710062China college of Physics and Optoelectronics Technology Baoji University of Arts and SciencesBaoji 721016China college of Mathematics and Information Science Baoji University of Arts and SciencesBaoji 721013China Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China Department of Physics Kansas State UniversityManhattanKS 66506USA School of Physics and Electronics Qiannan Normal College for NationalitiesDuyun 558000China School of Physics and Electronic Technology Liaoning Normal UniversityDalian 116029China

Electron–electron correlation plays an important role in the underlying dynamics in physics and *** is the simplest and most fundamental two-electron *** dynamic process of helium in a strong laser field is still a challenging issue because of the large calculation *** this study,a graphic processing unit(GPU)open ACC based ab initio numerical simulations package He TDSE is developed to solve the full-dimensional time-dependent Schrodinger equation of helium subjected to a strong laser *** TDSE uses B-spline basis sets expansion method to construct the radial part of the wavefunction,and the spherical harmonic functions is used to express for the angular *** algorithm is employed for the time *** example shows that He TDSE running on an NVIDIA Kepler K20 GPU can outperform the one on an Intel E5-2640 single CPU core by a factor of *** TDSE code package can be obtained from the author or from the author's personal website(doi:10.13140/RG.2.2.15334.45128)directly under the GPL license,so He TDSE can be downloaded,used and modified freely.

关键词： strong field physics TDSE OPENACC GPU electron correlation helium

Analysis on Climate Factors Change in Guizhou from 1981 to 2010

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Analysis on Climate Factors Change in Guizhou from 1981 to 2...

A Hybrid Marine Predator Algorithm for Thermal-aware Routing Scheme in Wireless Body Area Networks

作者： Ziyong YUAN Yufeng XU Hanli XIAO Juan HUANG School of Tourism and Resources Environment Qiannan Normal University for Nationalities School of Geography & Environmental Science Guizhou Normal University

There is no doubt about climate *** ecological environment in the karst region is fragile and climate change needs urgent *** analyzed the temporal and spatial characteristics of temperature and precipitation in Guizhou Province from 1981 to *** results showed that:（1） there is an increase trend of temperature with significant during in the study periods,while there was a decreased trend of the annual average precipitation.（2） The annual precipitation change rate of has significant spatial different,there was an upward trend in the eastern region while there was a downward trend in the western *** annual average temperature change rate has a large spatial variation,which is reflected in the upward trend in the western *** was an increasing trend in Bijie City,Liupanshui City and Qianxinan Prefecture,while there was a downward trend in the eastern regions,especially in the central region of Guiyang and the north of qiannan *** Guizhou Plateau belongs to the typical karst area,which is located in the upper reaches of the Pearl River and the ecological barrier zone in the middle and upper reaches of the Yangtze *** on climate change in the context of global change will help to take concrete measures to promote regional sustainable development.

关键词： climate change temperature precipitation Guizhou province

来源： cnki会议评论

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Journal of Bionic Engineering 2023年第1期20卷 81-104页

作者： Tao Hai Jincheng Zhou Mohammad Masdari Haydar Abdulameer Marhoon School of Computer and Information Qiannan Normal University for NationalitiesDuyun558000GuizhouChina Key Laboratory of Complex Systems and Intelligent Optimization of Guizhou Duyun558000GuizhouChina Institute for Big Data Analytics and Artificial Intelligence(IBDAAI) Universiti Teknologi MARA40450Shah AlamSelangorMalaysia Department of Computer Engineering Islamic Azad UniversityUrmia BranchUrmiaIran Information and Communication Technology Research Group Scientific Research CenterAl-Ayen UniversityThi-QarIraq college of Computer Sciences and Information Technology University of KerbalaKarbalaIraq

Thermal-aware routing protocols in WBANs consider temperature factors in the routing process for preventing overheating of the tissues surrounding the sensor ***,providing an energy-efficient and thermal-aware routing in WBANs is a challenging *** deal with this problem,this article presents a novel temperature-aware routing protocol that applies Mamdani-based Fuzzy Logic Controllers(FLCs)for selecting the next forwarding node in routing data *** FLCs apply five important input factors such as the priority of the packet,and sensor node's remaining energy,temperature,distance,and link path ***,a new hybrid version of the Marine Predator Algorithm(MPA),named MPAOA is presented by combining the exploration and exploitation phases of the MPA and Arithmetic Optimization Algorithm(AOA).This algorithm is effectively applied for selecting the best possible set of fuzzy rules for FLCs and tuning their fuzzy *** experiments conducted in the Castalia simulator exhibit that the proposed temperature and priority-aware routing scheme can outperform other well-known routing schemes such as LATOR,TTRP,TAEO,ATAR,and EOCC-TARA in terms of metrics such as sensor nodes lifetime,the average temperature of the sensor nodes,and the percentage of the packets routed through non-overheated ***,it is shown that the MPAOA outperforms other algorithms such as Bat Algorithm(BA),Genetic Algorithm(GA),AOA,and MPA regarding the specified metrics.

关键词： WBANs Multi-hop routing Temperature Priority Fuzzy logic Bio-inspiration