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Journal of Computational Mathematics 2001年第5期19卷 449-458页

作者： Wan, Z.-s. sun, Z.-Z. Institute of Applied Physics and CM P.O. Box 8009 Beijing 100088 China

In paper (J. Comput. Appl. Math., 76 (1996), 137-146), a difference scheme for a class of nonlocal parabolic equations with natural boundary conditions was derived by the method of reduction of order and the unique solvability and second order convergence in L2-norm are proved. In this paper, we prove that the scheme is second order convergent in L∞ norm and then obtain fourth order accuracy approximation in L∞ norm by extrapolation method. At last, one numerical example is presented.

关键词： Approximation theory Boundary conditions Convergence of numerical methods Extrapolation

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边境上的旅人

青年视觉 2018年第3期 168-185页

作者：韩烨 Yue Zhu Eniac martinez 不详

很少有摄影师像Eniacmartinez一样,如此详细地用相机描绘过一个国家的地理与文化版图。他的足迹遍布墨西哥内陆与海岸,多年来始终如一地记录着这片土地上古老的道路和族群。对Eniac martinez来说,与摄影相关的第一个词汇即是“旅程”。... 详细信息

很少有摄影师像Eniacmartinez一样,如此详细地用相机描绘过一个国家的地理与文化版图。他的足迹遍布墨西哥内陆与海岸,多年来始终如一地记录着这片土地上古老的道路和族群。对Eniac martinez来说,与摄影相关的第一个词汇即是“旅程”。无论是工作室里散落的石头、贝壳、面具,还是将身体与灵魂、生与死一并纳入创作范畴的作品,都是这些旅程的见证。

关键词：工作室文化版图身体与灵魂生与死摄影师墨西哥始终如一

synthesis and characterization of bulk composite Fe-si-B alloys with small concentration of Nb and Mo

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Acta Metallurgica sinica(English Letters) 2010年第6期23卷 401-408页

作者： s.Bez I.Betancourt I.A.Figueroa Institute for Materials Research National Autonomous University of Mexico (UNAM)

The preparation and some mechanical, thermal and magnetic properties of the as cast bulk composite ***4 （M=Nb, Mo） alloys obtained by suction casting are presented and discussed. The microstructrural results showed the existence of a crystalline a-Fe（si） phase embedded in a glassy matrix. The values of microhardness （/Iv） and yield strength （ay） for the Nb-containing alloy are exceptionally high, i.e. （12.65~0.3） GPa and （4.22~0.10） GPa, respectively. The saturation polarization values are found to be as high as 1.24 T for both composite ~11oys. It is thought that the interplay between the secondary crystalline phases and amorphous matrix could be responsible for the mechanical and magnetic behaviour of these alloys.

关键词： Bulk composite alloys Magnetic properties Mechanical proper- ties Thermal stability and suction casting

sexual Morph of Furcasterigmium furcatum (Plectosphaerellaceae) from Magnolia liliifera Collected in Northern Thailand

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Phyton-International Journal of Experimental Botany 2020年第3期89卷 765-777页

作者： Jutamart Monkai Ruvishika s.Jayawardena sajeewa s.N.Maharachchikumbura Kevin D.Hyde Center of Excellence in Fungal Research Mae Fah Luang UniversityChiang Rai57100Thailand school of science Mae Fah Luang UniversityChiang Rai57100Thailand school of Life science and Technology University of Electronic Science and Technology of ChinaChengdu611731China

We isolated an interesting fungus from dead leaves of Magnolia liliifera collected from Chiang Mai,*** novel strain is related to Plectosphaer-ellaceae based on the morphology of its asexual morph and the analysis of sequence *** analyses using a combined gene analysis of LsU and ITs sequence data showed that this strain is clustered in the same clade with Furcasterigmium furcatum with high statistical *** new strains produced the asexual morph in culture which is morphologically similar to ***,we identified this strain as the sexual morph of *** is the first record of sexual morph for the monotypic genus Furcasterigmium and the first record of this genus on Magnolia.

关键词： Acremonium phylogeny sexual morph sordariomycetes taxonomy

A review on recent advancements in biodegradable Mg-Ca alloys

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Journal of Magnesium and Alloys 2022年第8期10卷 2094-2117页

作者： Manas Ranjan sahu T.s.sampath Kumar Uday Chakkingal Department of Metallurgical and Materials Engineering Indian Institute of Technology MadrasChennai 600036India

The binary Mg-Ca alloys are drawing increasing attention as temporary implant materials because of their excellent biocompatibility,biodegradability, and good mechanical properties. However, their applications are limited due to their high degradation rates in the human physiological environment, the consequent release of hydrogen gas, and rapid loss in mechanical properties. Furthermore, biocompatibility depends upon the degradability of the material. Various researchers have demonstrated that these issues can be addressed by control of Ca content, thermo-mechanical processing to obtain suitable microstructures, deposition of surface coatings, etc. In this manuscript, a detailed review of published literature on Mg-Ca alloys is presented. The challenges and future directions of research in this area are also described.

关键词： Mg-Ca alloy Degradation Temporary implant Biocompatibility

Polycrystalline morphology and mechanical strength of nanotube fibers

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npj Computational Materials 2022年第1期8卷 180-185页

作者： Nitant Gupta Evgeni s.Penev Boris I.Yakobson Department of Materials science and NanoEngineering Rice UniversityHoustonTX77005USA

Correlating mechanical performance with mesoscale structure is fundamental for the design and optimization of light and strong fibers(or any composites),most promising being those from carbon *** all forms of nanotube fiber production strategies,due to tubes’mutual affinity,some degree of bundling into liquid crystal-like domains can be expected,causing heterogeneous load transfer within and outside these domains,and having a direct impact on the fiber *** employing large-scale coarse-grained simulations,we demonstrate that the strength s of nanotube fibers with characteristic domain size D scales as s~1/D,while the degree of longitudinal/axial disorder within the domains(akin to a smectic↔nematic phase transition)can substantially mitigate this dependence.

关键词： composites fibers strength

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詹妮弗·劳伦斯:初生牛犊不畏虎

疯狂英语（初中天地） 2012年第8期 8-10页

作者： Patty Adams martinez 芥子

《饥饿游戏》这部畅销小说在传出将改编成电影后，书中的女主角——16岁少女凯特尼斯．伊夫狄恩就成为许多好莱坞女星争夺的目标。最终，詹妮弗·劳伦斯从超过30位新生代女演员（包括海莉．斯坦菲尔德和阿比盖尔·布兰斯林等人）中脱颖... 详细信息

《饥饿游戏》这部畅销小说在传出将改编成电影后，书中的女主角——16岁少女凯特尼斯．伊夫狄恩就成为许多好莱坞女星争夺的目标。最终，詹妮弗·劳伦斯从超过30位新生代女演员（包括海莉．斯坦菲尔德和阿比盖尔·布兰斯林等人）中脱颖而出，出演了这部叫好又叫座的电影。如果你觉得凯特尼斯有惊人的自信，你应该见识一下她的扮演者——

关键词：劳伦斯初生牛犊畅销小说好莱坞女主角女演员新生代扮演者

Eigen-spectra in the Dirac-attractive radial problem plus a tensor interaction under pseudospin and spin symmetry with the sUsY approach

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Chinese Physics B 2013年第10期22卷 112-118页

作者： s.Arbabi Moghadam H.Mehraban M.Eshghi Young Researchers and Elite Club Central Tehran BranchIslamic Azad UniversityTehranIran Physics Department Faculty of SciencesSemnan UniversitySemnanIran Physics Department Imam Hossein Comprehensive UniversityTehranIran

We approximately solve the Dirac equation for attractive radial potential including a Coulomb-like tensor interaction under pseudospin and the spin symmetry limit for any arbitrary spin-orbit quantum number, by employing the supersymmetric （sUsY） quantum mechanics and supersymmetric shape invariance technique. We obtain the energy eigenvalue equation under the pseudospin and spin conditions. some numerical results are compared with those obtained by the Nikiforove-Uvarov （NU） method.

关键词： Dirac equation attractive radial sUsY Coulomb-like tensor potential

Effects of calcination temperature and time on the Ca3Co4O9 purity when synthesized using starch-assisted sol-gel combustion method

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Journal of Advanced Ceramics 2020年第2期9卷 162-172页

作者： M.A.MOHAMMED M.B.UDAY s.IZMAN school of Mechanical Engineering Faculty of EngineeringUniversiti Teknologi Malaysia(UTM)UTM Skudai 81310JohorMalaysia Centre for Advanced Composite Materials(CACM) Institute for Vehicle Systems and EngineeringUniversiti Teknologi MalaysiaUTM Skudai 81310JohorMalaysia Department of Materials Engineering College of EngineeringUniversity of BasrahBasrahIraq

Ca3Co4O9 is a p-type semiconducting material that is well-known for its thermoelectric(TE),magnetic,electronic,and electro-optic *** this study,sol–gel autoignition was used to prepare Ca3Co4O9 at different calcination temperatures(773,873,973,and 1073 K)and time(4,6,8,10,12,and 14 h)using starch as a *** phase and microstructure of the prepared Ca3Co4O9 powder were ***–differential thermal analysis(TGA)confirms that the final weight loss occurred at 1073 K to form Ca3Co4O9 stable *** variable-pressure scanning electron microscopy(VP-sEM)images show that the size of powder particles increases from 1.15 to 1.47μm as calcination time increases from 4 to 12 h,and the size remains almost constant thereafter.A similar pattern is also observed on the increment of the crystallite size and percentage of crystallinity with X-ray diffraction(XRD)*** highest crystallinity is found about 92.9%when the powder was calcinated at 1073 K for 12 and 14 h with 458 and 460Åcrystallite size,*** dispersive X-ray spectroscopy(EDs)analysis demonstrates that the calcinated powder has a high intensity of Ca,Co,and O with uniform ***-resolution transmission electron microscopy(HRTEM)images prove that there is no distinct lattice distortion defect on the crystal structure.

关键词： calcium cobalt oxide sol-gel starch combustion method crystallite size crystallinity

Effect of solid particle loading on nucleophilic addition of epoxy-resin to isophorone diisocyanate

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Particuology 2008年第1期6卷 24-29页

作者： Wei Zhang Richard s. Blackburn Abbas A. Dehghani-sanij Green Chemistry Group Centre for Technical Textiles University of Leeds Leeds LS2 9JT UK school of Mechanical Engineering University of Leeds Leeds LS2 9JT UK

In the preparation of surface coatings made of conductive composites consisting of conductive particulate fillers in a soft matrix, cracks will develop with increase of the particulate loading, which is believed to be related to the nucleophilic addition reaction between glycidyl end-capped poly （bisphenol A-co-epichlorohydrin） and isophorone diisocyanate molecules. This curing reaction is responsible for the generation of crosslinking network throughout the coatings. The influence of solid particle loading on the chemical reaction may be described as a volume-excluded effect, that is, the high solid particle loading will occupy the space between the functional groups thus preventing the chemical reaction to take place. As a direct consequence, the cross-linking network cannot develop properly due to the insufficiency of curing reaction. This will lead to the generation of cracks, as was supported by FT-IR analysis in this work.

关键词： Particle loading Cracks Nucleophilic Addition FT-IR