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Utilization of a spiropyran derivative in a polymeric film optode for selective fluorescent sensing of zinc ion

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Science china Chemistry 2006年第3期49卷 246-255页

作者： ZHANG Ying1, SHAO Na1, YANG Ronghua1, LI Ke’an1, LIU Feng1, CHAN Winghong2.& MO Tian2.1. College of Chemistry and Molecular Engineering, Peking university, Beijing 100871, {2. 2. Department of Chemistry, hong kong baptist university, hong kong, {2. College of Chemistry and Molecular Engineering Peking University Beijing China Department of Chemistry Hong Kong Baptist University Hong Kong China

A new spiropyran derivative was synthesized and first utilized in a polymericfilm-based optical sensor for zinc ion. Spiropyrans, combining the characteristics of metal bindingand signal transduction, show potential function in the design of optical chemical sensors(optodes) toward metal ions. When embedded in a plasticized poly (vinyl chloride) (PVC) membrane,the newly synthesized spiropyran derivative 1 exhibits obvious fluorescence enhancement at 630 nm inthe presence of zinc ion in aqueous solution. With the optimum condition described, the optodemembrane responds to zinc ion over a dynamic range of 4.94x10^(-7) to 4.15x10^(-4)mol·L^(-1), witha detection limit of 1.51x10^(-7) mol·L^(-1). The membrane not only displays excellentphotostability, reproducibility and reversibility, but also exhibits high selectivity toward zincion over transition metal ions including Hg^(2.), Cd^(2.), Pb^(2.), Cu^(2.), Fe^(3+) and commoncationic ions presented in the physiological fluids.

关键词： spiropyran, sensor, PVC membrane, zinc ion, fluorescent spectroscopy.

Numerical manifold method for steady-state nonlinear heat conduction using Kirchhoff transformation

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Science china(Technological Sciences) 2024年第4期67卷 992-1006页

作者： ZHANG LiMei kong Heng ZHENG hong Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing 100124China Beijing Municipal Construction Co. Ltd.Beijing 100048China

The numerical manifold method(NMM)introduces the mathematical and physical cover to solve both continuum and discontinuum problems in a unified *** this study,the NMM for solving steady-state nonlinear heat conduction problems is presented,and heat conduction problems consider both convection and radiation boundary ***,the nonlinear governing equation of thermal conductivity,which is dependent on temperature,is transformed into the Laplace equation by introducing the Kirchhoff *** transformation reserves linearity of both the Dirichlet and the Neumann boundary conditions,but the Robin and radiation boundary conditions remain ***,the NMM is employed to solve the Laplace equation using a simple iteration procedure because the nonlinearity focuses on parts of the problem domain ***,the temperature field is retrieved through the inverse Kirchhoff *** examples are analyzed,demonstrating the advantages of the Kirchhoff transformation over the direct solution of nonlinear equations using the NewtonRaphson *** study provides a new method for calculating nonlinear heat conduction.

关键词： numerical manifold method nonlinear heat conduction temperature-dependent thermal conductivity Kirchhoff transformation convection and radiation boundary conditions

铝超积累植物和铝排斥植物吸收和累积铝的机理

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生态学报 2002年第10期22卷 1653-1659页

作者：谢正苗黄铭洪叶志鸿浙江大学土水资源与环境研究所香港浸会大学生物系香港浸会大学生物系杭州31002. 香港

研究了香港茶园天然生态系统中铝超积累植物和铝排斥植物包括茶树 ( Camellia sinensis L.)、多花野牡丹 ( Melas-toma affine L.)、假苹婆 ( Sterculia lanceolata L.)、大罗伞紫金牛 ( Ardisia crenata L.)、相思树 ( Acacia formosa ... 详细信息

研究了香港茶园天然生态系统中铝超积累植物和铝排斥植物包括茶树 ( Camellia sinensis L.)、多花野牡丹 ( Melas-toma affine L.)、假苹婆 ( Sterculia lanceolata L.)、大罗伞紫金牛 ( Ardisia crenata L.)、相思树 ( Acacia formosa L.)和红楠 ( Machilusthunbergii Machilusthunbergii L.)对铝吸收和累积的机理。 6种植物新鲜根和茎的 p H值变化范围为 3～ 6 ,不同部位全铝含量变化幅度为 1 3～ 1 2.81 0 mg/kg(干重 ,下同 )。新鲜植物组织的 p H值是控制植物对铝吸收、转运和累积的最重要的因素。植物中的铝浓度随其 p H值降低而显著增加。供试 6种植物可分成两组 :一组是铝排斥植物 ,其 p H值大约 6 ,叶中含铝量范围为 1 7～ 1 5 1 mg/kg,包括假苹婆、大罗伞紫金牛、相思树和红楠 ;另一组是铝超积累植物 ,其 p H值为 3和 4 .5 ,叶中含铝量范围为 782.0～ 1 2.81 0 mg/kg,包括茶树和多花野牡丹。铝超积累植物新鲜根中水溶性铝与全铝的比例 ( 0 .1 1～ 0 .88)高于铝排斥植物根中的比例 ( 0 .0 4～ 0 .0 7)。相同趋势可见于茎和叶中 ,特别在多花野牡丹茎叶中。结果表明 :新鲜根、茎和叶中水溶性铝与全铝的比例高可以增加植物从土壤 -植物系统中铝的迁移速率 ,导致较高的铝吸收和累积。根际和非根际土

关键词：铝超积累植物排斥植物 pH 根际

Al_(1-x)Sc_(x)Sb_(y)N_(1-y):An opportunity for ferroelectric semiconductor field effect transistor

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Science china(Physics,Mechanics & Astronomy) 2024年第11期67卷 133-140页

作者： Shujin Guo Xianghua kong hong Guo College of Physics and Electronic Engineering Center for Computational SciencesSichuan Normal UniversityChengdu 610068China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Physics McGill UniversityMontreal H3A 2T8Canada

For the in-memory computation architecture,a ferroelectric semiconductor field-effect transistor(FeSFET)incorporates ferroelectric material into the FET channel to realize logic and memory in a single *** emerging groupⅢnitride material Al_(1-x)Sc_(x)N provides an excellent platform to explore FeSFET,as this material has significant electric polarization,ferroelectric switching,and high carrier ***,steps need to be taken to reduce the large band gap of~5 eV of Al_(1-x)Sc_(x)N to improve its transport property for in-memory logic *** state-of-the-art first principles analysis,here we predict that alloying a relatively small amount(less than~5%)of Sb impurities into Al_(1-x)Sc_(x)N very effectively reduces the band gap while maintaining excellent *** show that the co-doped Sb and Sc act cooperatively to give a significant band bowing leading to a small band gap of~1.76 eV and a large polarization parameter~0.87 C/m^(2.,in the quaternary Al_(1-x)Sc_(x)Sb_(y)N_(1-y)*** Sb impurity states become more continuous as a result of interactions with Sc and can be used for impurity-mediated *** on the Landau-Khalatnikov model,the Landau parameters and the corresponding ferroelectric hysteresis loops are obtained for the quaternary *** findings indicate that Al_(1-x)Sc_(x)Sb_(y)N_(1-y)is an excellent candidate as the channel material of FeSFET.

关键词： ferroelectricity Al_(1-x)Sc_(x)N FeSFET

MONOTONICITY CORRECTIONS FOR NINE-POINT SCHEME OF DIFFUSION EQUATIONS

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Journal of Computational Mathematics 2024年第5期42卷 1305-1327页

作者： Wang kong Zhenying hong Guangwei Yuan Zhiqiang Sheng School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Mathematical Modelling and High Performance Computing of Air Vehicles(NUAA) MIITNanjing 211106China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China

In this paper,we present a nonlinear correction technique to modify the nine-point scheme proposed in[SIAM ***.,30:3(2.08),1341-1361]such that the resulted scheme preserves the *** first express the flux by the cell-centered unknowns and edge unknowns based on the stencil of the nine-point ***,we use a nonlinear combination technique to get a monotone *** order to obtain a cell-centered finite volume scheme,we need to use the cell-centered unknowns to locally approximate the auxiliary *** present a new method to approximate the auxiliary unknowns by using the idea of an improved multi-points flux *** numerical results show that the new proposed scheme is robust,can handle some distorted grids that some existing finite volume schemes could not handle,and has higher numerical accuracy than some existing positivity-preserving finite volume schemes.

关键词： Monotonicity corrections Diffusion equation Improved MPFA Distorted meshes

NbB_(2.Modified Al-Cu Alloys Fabricated by Freeze-Ablation Casting under High Cooling Rate Solidification

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 921-938页

作者： Xiang kong Yu Wang hong Xu Haotian Fan Yuewu Zheng Beibei Xie School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

At present,improving the properties of aluminum alloys is generally achieved by increasing the cooling rate of the melt and adding micro-nano *** the cooling rate of the melt to improve the refining effect of grain refiner is still a difficult problem in the aluminum alloy casting *** innovative and environmentally friendly casting process,known as freeze ablation,was introduced during the preparation of an Al–NbB_(2. intermediate *** process significantly enhanced the cooling rate of the *** results indicated that the Al–NbB_(2. intermediate alloy produced under high cooling rates had a noticeable refining effect on Al–Cu alloys,with smaller NbB2.particles demonstrating superior refining *** average grain size of the refined Al–Cu alloy decreased from 154 to 69μm,the tensile strength increased by 12.,the fluidity increased by 18.4%,and the hot tearing index decreased from 144 to *** matching degree between NbB_(2. andα-Al was calculated using high-resolution transmission electron microscopy and the edge-to-edge *** was found that the atomic interplanar spacing and the interatomic spacing mismatch between NbB_(2.’s2.>plane and Al were both less than 10%,which further proved that NbB2.could serve as an effective nucleation site forα-Al grains to achieve grain refinement.

关键词： Grain refinement Freeze ablation Particle size control Mechanical properties Process properties

Dietary Supplementation of β-Carotene Reveals miRNAs Involved in the Regulation of Carotenoid Metabolism in Crassostrea gigas

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Journal of Ocean university of china 2024年第4期23卷 1045-1053页

作者： SUN Dongfang WAN Sai YU hong kong Lingfeng LI Qi Key Laboratory of Mariculture Ministry of EducationOcean University of ChinaQingdao 266003China Laboratory for Marine Fisheries Science and Food Production Processes Laoshan LaboratoryQingdao 266237China

Carotenoids play crucial physiological roles in animals.A comprehensive investigation into the mechanism of carotenoid metabolism in oysters will establish a theoretical foundation for further development of its carotenoid-rich ***,the information on the function of miRNA in β-carotene metabolism in oysters is *** elucidate the mechanisms underlying miRNA regulation of carotenoid metabolism in oysters,we compared the expressions of miRNA in digestive gland tissues of Pacific oyster(Crassostrea gigas)fed with aβ-carotene supplemented diet and a normal diet,respectively.A total of 690 candidate miRNAs in the Pacific oyster digestive gland tissues were identified,including 590 known miRNAs and 111 unknown *** differentially expressed miRNAs were obtained in the carotenoid-fed and normal groups,associated to 137 differentially expressed target ***,the GO enrichment analysis revealed that the differentially expressed target genes were mainly involved in transmembrane transport *** enrichment showed that the differentially expressed target genes were involved in ABC *** of the mRNA-miRNA network revealed that novel002. played a central role in carotenoid metabolism,and it was negatively correlated with the expression of 46 *** addition,down-regulated expression of novel002. upregulated the expression of the lipoprotein gene LOC105342.86,suggesting a potential regulatory role in carotenoid *** results provide useful information for elucidating the miRNA regulation mechanism during carotenoids metabolism in the Pacific oyster.

关键词： Crassostrea gigas β-carotene microRNA carotenoid metabolism

新的β-二酮及其Eu(Ⅲ)三元配合物的合成与发光研究

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中国稀土学报 2004年第6期22卷 871-874页

作者：向能军李狄豪王芸芸龚孟濂梁万里石建新中山大学光电材料与技术国家重点实验室化学与化学工程学院广州5102.5香港浸会大学化学系香港香港浸会大学化学系中山大学光电材料与技术国家重点实验室化学与化学工程学院

合成了一种新的β 二酮,4 甲氧基联苯甲酰三氟丙酮(1 (4′ meothoxybiphenyl 4yl ) 4,4,4, trifluoro butane 1,3 dione,MBPTFA),以元素分析和1H NMR谱确定了其组成;进而以MBPTFA作第一配体和邻菲罗啉(1,10 phenanthroline,Phen)为第二配体,与EuCl3反应,合成了一种三元配合,Eu(MBPTFA)3Phen。用元素分析、红外、紫外可见吸收光谱和荧光光谱进行了表征。荧光分析结果表明:配体本身是一种良好的蓝色发光材料;配合物中的有机配体能够有效地的把吸收的能量传递给中心Eu3+离子,强烈敏化Eu3+发光,且发射谱线很窄,主发射峰为Eu3+的5D0-7F2.射。这对寻找新型稀土配合物发光材料和制备有机电郅发光器件具有一定的价值。

关键词： Eu(Ⅲ) β-二酮三元配合物发光电子传导稀土

Biochar-based composites for removing chlorinated organic pollutants: Applications, mechanisms, and perspectives

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Environmental Science and Ecotechnology 2024年第5期21卷 47-61页

作者： Qingqing Song Fanying kong Bing-Feng Liu Xueting Song hong-Yu Ren State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin150090China School of Water Conservancy and Civil Engineering Northeast Agricultural UniversityHarbin150030China

Chlorinated organic pollutants constitute a significant category of persistent organic pollutants due to their widespread presence in the environment,which is primarily attributed to the expansion of agricultural and industrial *** pollutants are characterized by their persistence,potent toxicity,and capability for long-range dispersion,emphasizing the importance of their eradication to mitigate environmental *** conventional methods for removing chlorinated organic pollutants encompass advanced oxidation,catalytic oxidation,and bioremediation,the utilization of biochar has emerged as a prominent green and efficacious method in recent *** we review biochar's role in remediating typical chlorinated organics,including polychlorinated biphenyls(PCBs),triclosan(TCS),trichloroethene(TCE),tetrachloroethylene(PCE),organochlorine pesticides(OCPs),and chlorobenzenes(CBs).We focus on the impact of biochar material properties on the adsorption mechanisms of chlorinated *** review highlights the use of biochar as a sustainable and eco-friendly method for removing chlorinated organic pollutants,especially when combined with biological or chemical *** facilitates electron transfer efficiency between microorganisms,promoting the growth of dechlorinating bacteria and mitigating the toxicity of chlorinated organics through ***,biochar can activate processes such as advanced oxidation or nano zero-valent iron,generating free radicals to decompose chlorinated organic *** observe a broader application of biochar and bioprocesses for treating chlorinated organic pollutants in soil,reducing environmental ***,for water-based pollutants,integrating biochar with chemical methods proved more effective,leading to superior purification *** review contributes to the theoretical and practical application of biochar for removing environmental chlorinated organic pollutants.

关键词： Biochar Chlorinated organic pollutants Polychlorinated biphenyls Triclosan Trichloroethene