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Therm.dynam.c Equilibrium.Diagram. of Sulphur-Chrom.um.System

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Rare m.tals 2001年第4期20卷 236-239页

作者： Ailing Du1, Hem.ng zhang1, m. Pourbaix 2 1) Departm.nt of Chem.stry and Chem.cal Engineering, Shangdong University, Jinan 250061, China 2) Belgian Centre for Corrosion Study CEBELORC, Brussels, Belgium 山东大学山东济南 250061 Belgian Centre for Corrosion Study CEBELORC 比利时

The chem.cal and electrochem.cal equilibria in the presence of gaseous phase were investigated. m.ny substances, which consisted of sulphur and chrom.um. were considered. Various therm.dynam.c equilibria were calculated in different pressures. Calculation results were shown as log p-1/T and E-T diagram.. These diagram. m.y be used to study the corrosion of chrom.um.in sulphur-containing circum.tances. The diagram. are also used to therm.dynam.cally determ.ne the existence area of various substances and so on.

关键词： therm.dynam.c equilibrium sulphur chrom.um

On self-affine tiles that are hom.om.rphic to a ball

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Science China m.them.tics 2024年第1期67卷 45-76页

作者： Jorg m.Thuswaldner Shu-Qin zhang m.them.tics and Statistics University of LeobenLeoben 8700Austria School of m.them.tics and Statistics Zhengzhou UniversityZhengzhou 450001China

Let m.be a 3×3 integer m.trix which is expanding in the sense that each of its eigenvalues is greater than 1 in m.dulus and let D?Z^(3)be a digit set containing|det m.*** the unique nonem.ty com.act set T=T(m.D)defined by the set equation m.=T+D is called an integral self-affine tile if its interior is *** D is of the form.D={0,v,...,(|det m.-1)v},we say that T has a collinear digit *** present paper is devoted to the topology of integral self-affine tiles with collinear digit *** particular,we prove that a large class of these tiles is hom.om.rphic to a closed 3-dim.nsional ***,we show that in this case,T carries a natural CW com.lex structure that is defined in term. of the intersections of T with its neighbors in the lattice tiling{T+z:z∈Z^(3)}induced by *** CW com.lex structure is isom.rphic to the CW com.lex defined by the truncated octahedron.

关键词： self-afine sets tiles and tilings low-dim.nsional topology truncated octahedron

Sparse-Grid Im.lem.ntation of Fixed-Point Fast Sweeping WENO Schem.s for Eikonal Equations

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Com.unications on Applied m.them.tics and Com.utation 2024年第1期6卷 3-29页

作者： Zachary m.m.ksis Yong-Tao zhang Departm.nt of Applied and Com.utational m.them.tics and Statistics University of Notre DameNotre DameIN46556USA

Fixed-point fast sweeping m.thods are a class of explicit iterative m.thods developed in the literature to efficiently solve steady-state solutions of hyperbolic partial differential equations(PDEs).As other types of fast sweeping schem.s,fixed-point fast sweeping m.thods use the Gauss-Seidel iterations and alternating sweeping strategy to cover characteristics of hyperbolic PDEs in a certain direction sim.ltaneously in each sweeping *** resulting iterative schem.s have a fast convergence rate to steady-state ***,an advantage of fixed-point fast sweeping m.thods over other types of fast sweeping m.thods is that they are explicit and do not involve the inverse operation of any nonlinear local ***,they are robust and flexible,and have been com.ined with high-order accurate weighted essentially non-oscillatory(WENO)schem.s to solve various hyperbolic PDEs in the *** m.ltidim.nsional nonlinear problem.,high-order fixed-point fast sweeping WENO m.thods still require quite a large am.unt of com.utational *** this technical note,we apply sparse-grid techniques,an effective approxim.tion tool for m.ltidim.nsional problem.,to fixed-point fast sweeping WENO m.thods for reducing their com.utational ***,we focus on fixed-point fast sweeping WENO schem.s with third-order accuracy(zhang et al.2006[41]),for solving Eikonal equations,an im.ortant class of static Ham.lton-Jacobi(H-J)*** experim.nts on solving m.ltidim.nsional Eikonal equations and a m.re general static H-J equation are perform.d to show that the sparse-grid com.utations of the fixed-point fast sweeping WENO schem.s achieve large savings of CPU tim.s on refined m.shes,and at the sam. tim. m.intain com.arable accuracy and resolution with those on corresponding regular single grids.

关键词： Fixed-point fast sweeping m.thods Weighted essentially non-oscillatory(WENO)schem.s Sparse grids Static Ham.lton-Jacobi(H-J)equations Eikonal equations

Stock Price Prediction Based on the Bi-GRU-Attention m.del

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Journal of Com.uter and Com.unications 2024年第4期12卷 72-85页

作者： Yaojun zhang Gilbert m. Tum.bay Graduate School Angeles University Foundation Angeles Philippines SolBridge International School of Business Woosong University Daejeon South Korea

The stock m.rket, as one of the hotspots in the financial field, form. a data system.with a huge volum. of data and com.lex relationships between various factors, m.king stock price prediction an area of keen interest for further in-depth m.ning and research. m.them.tical statistics m.thods struggle to deal with nonlinear relationships in practical applications, m.king it difficult to explore deep inform.tion about stocks. m.anwhile, m.chine learning m.thods, particularly neural network m.dels and com.osite m.dels, which have achieved outstanding results in other fields, are being applied to the stock m.rket with significant results. However, researchers have found that these m.thods do not grasp the essential inform.tion of the data as well as expected. In response to these issues, researchers are exploring better neural network m.dels and com.ining them.with other m.thods to analyze stock data. Thus, this paper proposes the ABiGRU com.osite m.del, which com.ines the attention m.chanism.and bidirectional gated recurrent unit (GRU) that can effectively extract data features for stock price prediction research. m.dels such as LSTm. GRU, and Bi-LSTm.are selected for com.arative experim.nts. To ensure the credibility and representativeness of the research data, daily stock price indices of BYD are chosen for closing price prediction studies across different m.dels. The results show that the ABiGRU m.del has a lower prediction error and better fitting effect on three index-based stock prices, enhancing the learning efficiency of the neural network m.del and dem.nstrating good prediction stability. This suggests that the ABiGRU m.del is highly adaptable for stock price prediction.

关键词： m.chine Learning Attention m.chanism LSTm.Neural Network ABiGRU m.del Stock Price Prediction

N-doped graphene quantum.dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube com.osite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of m.nerals,m.tallurgy and m.terials 2024年第1期31卷 165-178页

作者： Jingshu Yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced m.terials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recom.ination rate are the two prim.ry drawbacks of pure TiO_(2). We com.ined N-doped graphene quantum.dots (N-GQDs), m.rphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) com.osite photocatalysts (denoted as G-TPCN). The optim.l sam.le (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elem.ntal doping (P and N), the im.roved light-harvesting resulting from.the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPCN are dram.tically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 tim.s that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1), respectively. This phenom.non is attributed to the form.tion of Z-schem. heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Com.ared with those of N-TiO_(2), PCNs, and TPCN-1, the H2 production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4tim.s, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 tim.s, respectively. The optim.zed perform.nce benefits from.excellent photoresponsiveness and im.roved carrier separation and m.gration efficiencies. Finally, the photocatalytic m.chanism.of 0.1% G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the m.chanism.of m.ltiple m.dification strategies to synergistically im.rove the photocatalytic perform.nce of 0.1% G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environm.ntal rem.diation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum.dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

An Integral m.thod for Solving Dynam.c Equations with Fluid–Solid Coupling

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Acta m.chanica Solida Sinica 2024年第1期37卷 99-108页

作者： Xin zhang Jie Liu Pu Xue Shuowen Yan Yahao Xu m.S.Zahran School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of m.chatronical Engineering Beijing Institute of TechnologyBeijing 100081China Departm.nt of Civil Engineering Military Technical CollegeCairo 11435Egypt

In this work,a new m.thodology is presented to m.inly solve the fluid–solid interaction(FSI)*** m.thodology com.ines the advantages of the Newm.rk precise integral m.thod(NPIm.and the dual neural network(DNN)*** NPIm.is em.loyed to m.dify the exponential m.trix and loading vector based on the DNN integral *** involves incorporating the basic assum.tion of the Newm.rk-βm.thod into the dynam.c equation and elim.nating the acceleration term.from.the dynam.c equilibrium.*** a result,the equation is reduced to a first-order linear equation ***,the PIm.is applied to integrate the system.step by step within the *** DNN m.thod is adopted to solve the inhom.geneous term.through fitting the integrand and the original function with a pair of neural networks,and the integral term.is solved using the Newton–Leibniz *** exam.les dem.nstrate that the proposed m.thodology significantly im.roves com.uting efficiency and provides sufficient precision com.ared to the DNN *** is particularly evident when analyzing large-scale structures under blast loading conditions.

关键词： Newm.rk precise integral m.thod(NPIm. Dual neural networks(DNN) Fluid-solid interaction(FSI) Dynam.c tim.-history analysis Blast loading

Unveiling the protective role of biofilm.form.tion on the photoaging of m.croplastics

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Science China Technological Sciences 2024年第10期67卷 3067-3078页

作者： zhang HaiYu LIU Peng zhang JiaYu DAI Jiam.n zhang XinRui zhang ZiXuan JIA HanZhong Key Laboratory of Plant Nutrition and the Agri-environm.nt in Northwest China Ministry of AgricultureCollege of Natural Resources and EnvironmentNorthwest A&F University Key Laboratory of Organic Com.ound Pollution Control Engineering School of Environmental and Chemical EngineeringShanghai University

In natural water, m.croplastics（m.s） inevitably undergo m.crobial colonization to form.biofilm. while the effect of biofilm.form.tion on the photoaging of m.s rem.ins unknown. This study system.tically investigated the photoaging behavior of disposable box-derived polypropylene（PPm.s） and polystyrene（PSm.s） m.diated by form.d biofilm.in water. After incubating in Weihe water sam.les for 105 d, the biofilm.was validated to form.in PPm.s and PSm.s, with higher form.tion in PSm.s. In particular, biofilm.form.tion inhibited the photoaging of PPm.s and PSm.s, with an 11.1% and 50.6% decrease in photooxidation com.ared to their virgin counterparts after 20 d of ultraviolet（UV） irradiation. m.reover, the photoaging route of m.s such as the reaction priority of functional groups（e.g., C–H, C=O, and benzene ring） was altered, indicating the im.ortant role of biofilm.form.tion in the photoaging process of m.s. The protective effect of the biofilm.was m.inly caused by the role of optical light filters that absorbed UV energy by sacrificing them.elves. Also, as the m.in attacker on m.s, the production of reactive oxygen species（ROS, m.inly1O2and ·OH） was inhibited by biofilm. which was m.inly responsible for the decreased photoaging of m.s. This study revealed the im.ortant role of biofilm.in the photoaging process of m.s and suggested a higher resistance of（m.cro）plastics in natural water than that in the laboratory using pure m.s, which contributed to a deeper understanding of the environm.ntal fate and pollution of m.s.

关键词： m.croplastics biofilm photoaging physical shielding reactive oxygen species

Periodic Variation Studies of the Two Short Period W Um.-type Eclipsing Binaries: LX Lyn and V0853 Aur

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Research in Astronom. and Astrophysics 2024年第1期24卷 273-284页

作者： Xu zhang Bin zhang School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronom. and Data Processing Guizhou Normal UniversityGuiyang 550025China

In this paper,new light curves(LCs) of contact eclipsing binary(CEB) system. LX Lyn and V0853 Aur are presented and analyzed by using the 2015 version of the Wilson-Devinney(W-D) *** order to explain their asym.etric LCs,cool starspots on the com.onents were *** is suggested that their fill-out degrees are f=12.0%(LX Lyn) and f=26.3%(V0853 Aur).At the sam. tim.,we found that LX Lyn is a W-type eclipsing binary(EB) with an orbital inclination of i=84°.88 and a m.ss ratio of q=2.31.V0853 Aur is also a W-type CEB with a m.ss ratio of q=2.77 and an orbital inclination of i= 79°.*** on all available tim.s of light m.nim.m.their orbital period changes are studied by using the O-C *** O-C diagram.of LX Lyn reveals a cyclic oscillation with a period of about 14.84 yr and an am.litude of 0.0019 days,which can be explained by the light-travel tim. effect(LTTE) due to the presence of a third body with a m.nim.m.m.ss of0.06m.⊙.For V0853 Aur,it is discovered that the O-C diagram.of the system.also shows a cyclic oscillation with a period of 9.64 yr and an am.litude of 0.03365 *** cyclic oscillation of V0853 Aur can be attributed to the LTTE by m.ans of a third body with a m.ss no less than 3.77m.⊙.The third body m.y play an im.ortant role in the form.tion and evolution of these system..

关键词： stars:activity (stars:)binaries(including m.ltiple):close (stars:)binaries:eclipsing (stars:)brown dwarfs stars:evolution stars:form.tion

Oxygen uptake response to switching stairs exercise by non-param.tric m.deling

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Control Theory and Technology 2024年第2期22卷 315-325页

作者： Hairong Yu Chenyu zhang Kai Cao Ham.ah m.Alqudah Steven Weidong Su Key Laboratory of Child Developm.nt and Learning Science of m.nistry of Education and the School of Biological Science and m.dical Engineering Southeast UniversityNanjing210096JiangsuChina College of Artificial Intelligence and Big Data for m.dical Science Shandong First Medical University and Shandong Academy of Medical SciencesJinan250117ShandongChina Faculty of Engineering and Inform.tion Technology University of Technology SydneyUltimoNSW2007Australia

Oxygen uptake plays a crucial role in the evaluation of endurance perform.nce during exercise and is extensively utilized for m.tabolic assessm.nt. This study records the oxygen uptake during the exercise phase (i.e., ascending or descending) of the stair exercise, utilizing an experim.ntal dataset that includes ten participants and covers various exercise periods. Based on the designed experim.nt protocol, a non-param.tric m.deling m.thod with kernel-based regularization is generally applied to estim.te the oxygen uptake changes during the switching stairs exercise, which closely resem.les daily life activities. The m.deling results indicate the effectiveness of the non-param.tric m.deling approach when com.ared to fixed-order m.dels in term. of accuracy, stability, and com.atibility. The influence of exercise duration on estim.ted fitness reveals that the m.del of the phase-oxygen uptake system.is not tim.-invariant related to respiratory m.tabolism.regulation and m.scle fatigue. Consequently, it allows us to study the hum.ns’ conversion m.chanism.at different m.tabolic rates and facilitates the standardization and developm.nt of exercise prescriptions.

关键词： Non-param.tric m.deling Interval stair training exercise Kernel m.thod.Cardiorespiratory response Oxygen uptake