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Restricted Arc-Connectivity of Harary Digraphs

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Journal of the Operations Research Society of China 2024年第2期12卷 540-547页

作者： Jun-Hao Zhang ji-xiang Meng College of Mathematics and System Science Xinjiang UniversityUrumqi 830046XinJiangChina

The h-restricted arc-connectivity of a digraph is an important parameter to measure fault-tolerance of interconnection *** paper determines that the h-restricted arc-connectivity of the Harary digraph D=G(n;1,2,.:,k)i... 详细信息

关键词： Restricted arc-connectivity λ_(h)(D) Super-λ_(h) λ_(h)-Atom λ_(h)-Superatom

The silicate and carbon-rich models of CoRoT-7b,Kepler-9d and Kepler-10b

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Research in Astronomy and Astrophysics 2012年第6期12卷 678-692页

作者： Yan-xiang Gong ji-Lin Zhou Department of Astronomy ＆ Key Laboratory of Modern Astronomy and Astrophysics inMinistry of Education Nanjing University Nanjing 210093 China College of Physics and Electronic Engineering Taishan University Taian 271021 China

Possible bulk compositions of the super-Earth exoplanets CoRoT-7b, Kepler-9d, and Kepler-10b are investigated by applying a commonly used silicate model and a non-standard carbon model. Their internal structures are deduced using a suitable equation of state for the materials. The degeneracy problems of their compo- sitions can be partly overcome, based on the fact that all three planets are extremely close to their host stars. By analyzing the numerical results, we conclude： 1） the iron core of CoRoT-7b is not more than 27% of its total mass within lc~ mass-radius error bars, so an Earth-like composition is less likely, but its carbon rich model can be com- patible with an Earth-like core/mantle mass fraction; 2） Kepler-10b is more likely to have a Mercury-like composition, with its old age implying that its high iron content may be a result of strong solar wind or giant impact; 3） the transiting-only super-Earth Kepler-9d is also discussed. Combining its possible composition with the formation theory, we can place some constraints on its mass and bulk composition.

关键词： planets and satellites: general -- methods: numerical -- planets andsatellites: individual (CoRoT-7b Kepler-9d Kepler- 10b)

Optimal Dividend Strategy in Compound Binomial Model with Bounded Dividend Rates

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 859-870页

作者： ji-yang TAN xiang-qun YANG School of Mathematics and Computational Science Xiangtan University College of Mathematics and Computer Science Hunan Normal University

We consider the compound binomial model, and assume that dividends are paid to the shareholders according to an admissible strategy with dividend rates bounded by a *** company controls the amount of dividends in order to maximize the cumulative expected discounted dividends prior to ruin. We show that the optimal value function is the unique solution of a discrete HJB equation. Moreover, we obtain some properties of the optimal payment strategy, and offer a simple algorithm for obtaining the optimal strategy. The key of our method is to transform the value function. Numerical examples are presented to illustrate the transformation method.

关键词： compound binomial model optimal dividend strategy transformation

3-restricted connectivity of graphs with given girth

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Applied Mathematics(A Journal of Chinese Universities) 2008年第3期23卷 351-358页

作者： GUO Li-tao MENG ji-xiang College of Math. and Sys. Sci. Xinjiang Univ. Xinjiang 830046 China

Let G = （V, E） be a connected graph. X belong to V（G） is a vertex set. X is a 3-restricted cut of G, if G- X is not connected and every component of G- X has at least three vertices. The 3-restricted connectivity κ3（G）（in short κ3） of G is the cardinality of a minimum 3-restricted cut of G. X is called κ3-cut, if ｜X｜ = κ3. A graph G is κ3-connected, if a 3-restricted cut exists. Let G be a graph girth g ≥ 4, κ3（G） is min{d（x）＋ d（y）＋ d（z） - 4 ： xyz is a 2-path of G}. It will be shown that κ3（G） = ξ3（G） under the condition of girth.

关键词： 3-restricted cut 3-restricted connectivity girth

On all-propulsion design of integrated orbit and attitude control for inner-formation gravity field measurement satellite

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Science China(Technological Sciences) 2011年第12期54卷 3233-3242页

作者： ji Li LIU Kun xiang JunHua Institute of Aerospace and Material Engineering National Universitry of Defense Technology Changsha 410073 China

The inner-formation gravity field measurement satellite （IFS） is a novel pure gravitational orbiter. It aims to measure the Earth＇s gravity field with unprecedented accuracy and spatial resolution by means of precise orbit determination （POD） and relative state measurement. One of the key factors determining the measurement level is the outer-satellite control used for keeping the inner-satellite flying in a pure gravitational orbit stably. In this paper the integrated orbit and attitude control of IFS during steady-state phase was investigated using only thrusters. A six degree-of-freedom translational and rotational dynamics model was constructed considering nonlinearity resulted from quaternion expression and coupling induced by community thrusters. A feasible quadratic optimization model was established for the integrated orbit and attitude control using con- strained nonlinear model predictive control （CNMPC） techniques. Simulation experiment demonstrated that the presented CNMPC aigorithm can achieve rapid calculation and overcome the non-convexity of partial constraints. The thruster layout is rational with low thrust consumption, and the mission requirements of IFS are fully satisfied.

关键词： gravity field measurement satellite inner-formation integrated orbit and attitude control model predictive techniques

A comparison between magnetic shear and flare shear in a well-observed M-class flare

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Chinese Journal of Astronomy and Astrophysics 2009年第3期9卷 323-332页

作者： Tuan-Hui Zhou Hai-sheng ji Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

We give an extensive multi-wavelength analysis of an eruptive M1.0/1N class solar flare, which occurred in the active region NOAA 10044 on 2002 July 26. Our emphasis is on the relationship between magnetic shear and flare shear. Flare shear is defined as the angle formed between the line connecting the centroids of the two ribbons of the flare and the line perpendicular to the magnetic neutral line. The magnetic shear is computed from vector magnetograms observed at Big Bear Solar Observatory （BBSO）, while the flare shear is computed from Transition Region and Coronal Explorer （TRACE） 1700A images. By a detailed comparison, we find that; 1） The magnetic shear and the flare shear of this event are basically consistent, as judged from the directions of the transverse magnetic field and the line connecting the two ribbons＇ centroids. 2） During the period of the enhancement of magnetic shear, flare shear had a fast increase followed by a fluctuated decrease. 3） When the magnetic shear stopped its enhancement, the fluctuated decreasing behavior of the flare shear became very smooth. 4） Hard X-ray （HXR） spikes are well correlated with the unshearing peaks on the time profile of the rate of change of the flare shear. We give a discussion of the above phenomena.

关键词： Sun flare - Sun magnetic field - Sun sunspot

Improved and efficient synthesis of Maxacalcitol

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Chinese Chemical Letters 2014年第5期25卷 771-774页

作者： Shi Feng Li-Fei Cui He-Geng Wei Guo-Jun Zheng Ya-Ping Wang xiang-jing Wang ji Zhang Wen-sheng xiang College of Science Northeast Agricultural University School of Life Science Northeast Agricultural University Harbin FRP Institute Zhejiang Hisun Pharmaceutical Co. Ltd.

Maxacalcitol,the 22-oxa-derivative of 1a,25-dihydroxyvitamin D3,has been used as an antihyperparathyroidism and antipsoriatic *** this paper,an alternative synthetic route has been developed using commercially available vitamin D2as the starting *** addition,as a key intermediate,the asymmetric synthesis of 20（S）-alcohol 14 with the chiral auxiliary（R-CBS） was described for the first *** new synthetic route afforded Maxacalcitol with improved overall yield（13.9%） in eleven steps.

关键词： Vitamin D3 derivative Maxacalcitol Synthesis Asymmetric reduction

An ROS-Responsive Antioxidative Macromolecular Prodrug of Caffeate for Uveitis Treatment

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Chinese Journal of Polymer Science 2022年第9期40卷 1101-1109页

作者： Yu-Tong Li Si-Ting sheng Bo Yu Fan jia Kai Wang Hai-jie Han Qiao jin You-xiang Wang jian ji MOE Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China Eye Center the Second Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310009China

Uveitis is a sophisticated syndrome showing a high relevance with reactive oxygen species(ROS).Herein,an ROS-responsive PEGylated polypeptide based macromolecular prodrug of herbaceous antioxidant ethyl caffeate(EC)is designed via phenylboronic esters with improved solubility for the alleviation of *** antioxidative 4-hydroxybenzyl alcohol(HBA)and EC can be released from the macromolecular EC prodrug under the stimulation of ROS,which can effectively protect cells against oxidative stress-induced injury in an ROS-depletion *** antioxidative and protective effects of the macromolecular EC prodrug in vivo are further verified in a uveitis mouse ***,this work not only provides a handy method to synthesize a phenylboronic ester-bearing EC prodrug which is highly sensitive to pathological ROS,but also depicts a promising future to apply macromolecular antioxidative prodrugs in the treatment of uveitis as well as other ROS-related diseases.

关键词： Antioxidative therapy Macromolecular prodrug Uveitis Ethyl caffeate(EC) Phenylboronic acid esters

High-performance sodium storage for cobalt phosphide composite array electrodes

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Rare Metals 2024年第8期43卷 3724-3734页

作者： Man Zhang Xiao-Xu Liu Tian-Yi ji Yang Li Da-Wei sheng Shao-Dong Li Pei-Pei Ren Ze-xiang Shen School of Material Science and Engineering Shaanxi University of Science and TechnologyXi'an 710021China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore 637371Singapore

Transition metal phosphides hold great potential as sodium-ion batteries anode materials owing to their high theoretical capacity and modest ***,volume changes and low intrinsic conductivity seriously largely hinder the further development of metal phosphide *** design of phosphide anode materials with reasonable structure is conducive to solving the problems of volume expansion and slow reaction kinetics during the *** this work,a composite material integrating zeolite imidazolate backbone(ZIF) and carbon materials was synthesized by the original growth ***,by the oxidation-phosphating process,CoP nanoarray composites riveted to carbon fiber(CoP@CF) were *** the CoP@CF,CoP nanoparticles are uniformly distributed on ZIF-derived carbon,reducing agglomeration and volume change during *** also provides a highly conductive network for the active material,improving the electrode ***,when evaluated as an anode for sodium-ion batteries,CoP@CF electrode displays enhanced reversible capacity(262 mAh·g^(-1) at 0.1 A·g^(-1)after 100 cycles),which is much better than that of pure CF electrode(57 mAh·g^(-1) at 0.1 A·g^(-1) after 100 cycles)prepared without the addition of *** rate performance of CoP@CF electrode is also superior to that of pure CF electrode at various current densities from 0.05 to1 A·g^(-1).The sodium storage behavior of CoP@CF was revealed by ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,and synchrotron radiation absorption *** method provides a reference for the design and synthesis of anode materials in sodium-ion batteries.

关键词： Cobalt phosphide Array structure Freestanding anodes Sodium-ion batteries