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High Order block Method for Third Order ODEs

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Computers, Materials & Continua 2021年第4期67卷 1253-1267页

作者： A.I.Asnor S.A.M.Yatim z.b.Ibrahim N.zainuddin School of Distance Education Universiti Sains MalaysiaUSM Penang11800Malaysia Department of Mathematics Faculty of ScienceUniversiti Putra MalaysiaSerdangSelangor Darul Ehsan43400Malaysia Department of Fundamental and Applied Sciences Universiti Teknologi PETRONASSeri IskandarPerak Darul Ridzuan32610Malaysia

Many initial value problems are difficult to be solved using ordinary,explicit step-by-step methods because most of these problems are considered *** implicit methods,however,are capable of solving stiff ordinary differential equations(ODEs)usually found in most applied *** study aims to develop a new numerical method,namely the high order variable step variable order block backward differentiation formula(VSVOHObbDF)for the main purpose of approximating the solutions of third order *** computational work of the VSVO-HObbDF method was carried out using the strategy of varying the step size and order in a single *** order of the proposed method was then discussed in *** advancement of this strategy is intended to enhance the efficiency of the proposed method to approximate solutions *** order to confirm the efficiency of the VSVO-HObbDF method over the two ODE solvers in MATLAb,particularly ode15s and ode23s,a numerical experiment was conducted on a set of stiff *** numerical results prove that for this particular set of problem,the use of the proposed method is more efficient than the comparable ***-HObbDF method is thus recommended as a reliable alternative solver for the third order ODEs.

关键词： block method stiff ODEs third order variable step variable order

Novel one-step synthesis of silica nanoparticles from sugarbeet bagasse by laser ablation and their effects on the growth of freshwater algae culture

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Particuology 2014年第6期12卷 29-35页

作者： Nalan Oya San Canan Kursung?z Yasin Tümtas ?ncay Yasa bülend Orta? Turgay Tekinay Polath Science and Literature Faculty Biology DepartmentGazi University Life Sciences Application and Research Center Gazi University UNAM Institute of Materials Science and Nanotechnology Bilkent University

Scientific research involving nanotechnology has grown exponentially and has led to the development of engineered nanoparticles（NPs）.Silica NPs have been used in numerous scientific and technological applications over the past decade,necessitating the development of efficient methods for their *** studies have explored the potential of laser ablation as a convenient way to prepare metal and oxide *** to its high silica content,low cost,and widespread availability,sugarbeet bagasse is highly suitable as a raw material for producing silica NPs via laser *** this study,two different NP production methods were investigated：laser ablation and NaOH *** developed a novel,one-step method to produce silica NPs from sugarbeet bagasse using laser ablation,and we characterized the silica NPs using environmental scanning electron microscopy（ESEM）,energy dispersive spectrometry（EDS）,dynamic light scattering（DLS）,transmission electron microscopy（TEM）,attenuated total reflectanceFourier transform infrared spectroscopy（ATR-FT1R）,X-ray photoelectron spectroscopy（XPS） and Raman *** analysis and XPS confirmed the presence of silica *** NPs produced by laser ablation were smaller（38-190 nm） than those produced by NaOH treatment（531-825 nm）.Finally,we demonstrated positive effects of silica NPs produced from laser ablation on the growth of microalgae,and thus,our novel method may be beneficial as an environmentally friendly procedure to produce NPs.

关键词： Laser ablation One-step synthesis Raman Silica nanoparticle Microalgae

Effects of Growth Temperature on Structural and Electrical Properties of Li-N-H Codoped znO

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Journal of Materials Science & Technology 2013年第2期29卷 154-156页

作者： Y.F. Lu z.z. Ye L.P. zhu Y.J. zeng J.Y. Huang b.H. zhao State Key Laboratory of Silicon Materials Department of Materials Science and Engineering Zhejiang University

Effects of growth temperature on the structural and electrical properties of Li-N-H codoped znO thin films grown by DC reactive magnetron sputtering were investigated. Scanning electron microscopy and X-ray diffraction results showed that increasing growth temperature could improve the crystalline quality. but Hall measurement results showed that growth temperature had a nonlinear influence on the electrical property. The variation of electrical properties with the growth temperature was found to be related to the activated concentration of N in znO and the evaporation of Li during the growth process, derived from the Hall measurement and the second ion mass spectroscopy measurement.

关键词： znO Codoped Growth temperature Structural property Electrical property

binding Reaction of Hemin with Chloroquine, Quinine and Quinidine in Water-propylene Glycol Mixture

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Chinese Journal of Chemistry 2003年第8期21卷 1022-1025页

作者： MAVAKALA b. K. NLANDU b. b. MPIANA P. T. GUSHIMANA z. Y. 尉志武 Ministry of Education Key Laboratory of bioorganic Phosphorous Chemistry & Chemical biology Department of Chemistry Tsinghua University Department of Chemistry Biomacromolecules Laboratory Kinshasa University B.P. 190 Kinshasa R. D. Congo

The interaction of hemin with chloroquine, quinine and quini-dine wasinvestigated in 50% water-propylene glycol mixture at pH = 9, 8.1, 7.4 and 6.8 using aspectrophotometric method. The data could be well fitted into a model consistent with the formationof a 1:1 complex between the reacting partners. In addition, the results indicated that hemincomplexed more strongly with quinidine than with chloroquine and quinine, and the binding constantswere pH-dependent. Moreover, it was proved that the water-propylene glycol mixture is well suitableto the study of the systems containing hemin and quinoline-based drugs.

关键词： hemin antimalarial drug complex pH-depen- dence propylene glycol

青藏高原及其周边成冰纪-埃迪卡拉纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 936-967页

作者：孙郎 Malik Muhammad Saud Sajid KHAN 杨传孙智新潘兵 Shehryar AHMED 苗兰云孙玮辰胡春林孙晓娟罗翠陈波殷宗军赵方臣李国祥朱茂炎中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学地球与行星科学学院北京100049

青藏高原及其周边的块体,包括印度板块、拉萨地块、羌塘地块、塔里木板块、欧龙布鲁克地块、中祁连地块、阿拉善地块、华北板块、扬子板块、中伊朗地块和阿曼等,以及各块体之间造山带的复杂演化历史是地球科学研究的前沿和热点.成冰系... 详细信息

青藏高原及其周边的块体,包括印度板块、拉萨地块、羌塘地块、塔里木板块、欧龙布鲁克地块、中祁连地块、阿拉善地块、华北板块、扬子板块、中伊朗地块和阿曼等,以及各块体之间造山带的复杂演化历史是地球科学研究的前沿和热点.成冰系和埃迪卡拉系广泛分布于该地区的各个构造单元,其中阿曼、印度板块、扬子板块以及塔里木板块发育有相对完整的成冰系和埃迪卡拉系;而在中伊朗地块、南羌塘地块、中祁连地块、阿拉善地块及华北板块,目前已知仅有埃迪卡拉系发育.基于前人对青藏高原及其周边地区成冰系和埃迪卡拉系的研究,结合第二次青藏高原综合科学考察研究项目开展以来获得的新资料和研究进展,本文建立了该地区成冰系和埃迪卡拉系代表性地层序列对比表.在此基础上,本文梳理了该地区这一时期生物群和重大地质事件的研究现状和存在的问题.结果表明,该地区各板块埃迪卡拉纪化石的保存和组合面貌各具特色,但普遍发现有典型埃迪卡拉纪末期化石分子Cloudina和Shaanxilithes;除成冰纪两次全球性冰期事件外,在青藏高原北缘各块体(华北板块、阿拉善地块、北祁连构造带、中祁连地块、欧龙布鲁克地块、塔里木板块)以及伊朗中南部普遍记录了一次埃迪卡拉纪晚期的冰川事件,但该事件的时限、分布范围和成因有待进一步揭示;同时,埃迪卡拉纪中期DOUNCE/Shruam碳同位素负异常事件在青藏高原周边地区也具有广泛记录.综合现有研究资料发现,在成冰纪-埃迪卡拉纪期间,青藏高原及其周边地区大多数块体从罗迪尼亚超大陆裂解出来后,可能通过泛非运动构成东冈瓦纳大陆的一部分,而部分板块(如华北板块)位于冈瓦纳大陆和劳伦大陆之间.总体而言,该地区的主要块体在成冰纪-埃迪卡拉纪期间具体的古地理演化模型存在较多争议,亟需开展进一步的研究工作.

关键词：青藏高原成冰系埃迪卡拉系地层古地理生物群冈瓦纳大陆

Giant magnetocaloric effect in Tb_5Ge_(2-x)Si_(2-x)Mn_(2x) compounds

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Chinese Physics b 2010年第5期19卷 542-548页

作者： E.Yzak b.Emre Y.Elerman A.Ycel Department of Engineering Physics Faculty of EngineeringAnkara University06100 BesevlerAnkaraTurkey Faculty of Science and Letters Physics DepartmentMugla UniversityKtekli 48000 MuglaTurkey

The crystal structure, magnetic and magnetocaloric characteristics of the pseduo ternary compounds of TbsGe2-xSi2-xMn2x （0 ≤ 2x ≤ 0.1） were investigated by x-ray powder diffraction and magnetization measurements. The x-ray powder diffraction results show that all compounds preserve the monoclinic phase as the majority phase and all the synthesized compounds were observed to be ferromagnetic from magnetization measurements. Magnetic phase transitions were interpreted in terms of Landau theory. Maximum isothermal magnetic entropy change value （20.84 J-kg-1 -K-1） was found for Tb5Ge1.95Si1.95Mn0.1 at around 123 K in the magnetic field change of 5T.

关键词： magnetic properties magnetocaloric effect isothermal magnetic entropy change

邛海国家湿地公园社会生态系统服务价值变化数据集(2009、2019)研发

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全球变化数据学报（中英文） 2024年第1期8卷 98-103,V0098-V0103页

作者：李勇冯晓张予倩赵振斌新疆师范大学地理科学与旅游学院乌鲁木齐830054 陕西师范大学地理科学与旅游学院西安710119

邛海国家湿地公园规划建设引起了征地搬迁和土地利用变化,关注社区居民感知的社会生态系统服务价值变化,对于湿地生态系统的可持续管理和增进居民福祉具有重要意义。作者采用访谈、参与式制图、理论探讨等方法进行数据采集,并进行数据... 详细信息

邛海国家湿地公园规划建设引起了征地搬迁和土地利用变化,关注社区居民感知的社会生态系统服务价值变化,对于湿地生态系统的可持续管理和增进居民福祉具有重要意义。作者采用访谈、参与式制图、理论探讨等方法进行数据采集,并进行数据空间化,得到邛海国家湿地公园社会生态系统服务价值变化数据集(2009、2019)。数据集由29个数据文件组成,内容包括:(1)访谈调查表;(2)调研对象社会经济特征;(3)2009年公园建设前社会生态系统服务价值类型表;(4)2019年公园建设后社会生态系统服务价值类型表;(5)2009年公园建设前社会生态系统服务价值类型点数据;(6)2019年公园建设后社会生态系统服务价值类型点数据;(7)公园土地利用与注记点数据。数据存储为.xlsx和.shp格式,数据量为991 Kb。

关键词：社会生态系统服务价值参与式制图湿地公园邛海

Application of continuous spectra of radii of influence and some other possibilities of generalisation of subsidence trough description

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中国有色金属学会会刊：英文版 2005年第S1期15卷 269-271页

作者： b. Drz■z'la Silesian University of Technology Gliwice Poland

The paper presents some possibilities of improvement in the subsidence trough description in relation to the description provided by influence function methods. These possibilities rely in a new approach to the values of theory parameters. Instead of one value of a certain theory parameter it is assumed that it can vary within an interval (in particular infinite one) and each value within that interval is given a weight. Thus we receive a distribution of the values of the parameter considered analogical to the probability distribution of a random variable.

关键词： continuous spectra knothe’s model subsidence trough

Simulation of Wave-Flow-Cavitation Interaction Using a Compressible Homogenous Flow Method

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Communications in Computational Physics 2013年第7期14卷 328-354页

作者： J.G.zheng b.C.Khoo z.M.Hu Department of Mechanical Engineering National University of SingaporeSingapore 119260 Singapore-MIT Alliance National University of SingaporeSingapore 117576 Temasek Laboratories National University of SingaporeSingapore 117411

A numerical method based on a homogeneous single-phase flow model is presented to simulate the interaction between pressure wave and flow *** account for compressibility effects of liquid water,cavitating flow is assumed to be compressible and governed by time-dependent Euler equations with proper equation of state(EOS).The isentropic one-fluid formulation is employed to model the cavitation inception and evolution,while pure liquid phase is modeled by Tait equation of *** of large stiffness of Tait EOS and great variation of sound speed in flow field,some of conventional compressible gasdynamics solvers are unstable and even not applicable when extended to calculation of flow *** overcome the difficulties,a Godunov-type,cell-centered finite volume method is generalized to numerically integrate the governing equations on triangular *** boundary is treated specially to ensure stability of the *** method proves to be stable,robust,accurate,time-efficient and *** numerical experiments are designed to investigate unsteady dynamics of the cavitating flow impacted by pressure wave,which is of great interest in engineering applications but has not been studied systematically so *** simulation indicates that cavity over cylinder can be induced to collapse if the object is accelerated suddenly and extremely high pressure pulse results almost ***,however,may be avoided by changing the traveling speed *** accompanying huge pressure increasemay damage underwater ***,cavity formed at relatively high upstream speed may be less distorted or affected by shock wave and can recover fully from the initial *** is observed that the cavitating flow starting from a higher freestream velocity is more stable and more resilient with respect to perturbation than the flow with lower background *** findings may shed some light on how to control cavitation development

关键词： Cavitating flow isentropic cavitation model shock-flow-cavitation interaction