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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-Ru Yang jin-dong zhang dong-Ting Gao Gang Liu Chun-Hai Chen Jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing *** effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

Time Modulated Array Antennas: A Review

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Electromagnetic Science 2024年第1期2卷 1-19页

作者： Wen Wu Qiaoyu Chen jin-dong zhang Tongde Huang Da-Gang Fang Laboratory of Near-Range RF Sensing ICs&Microsystems(NJUST) Ministry of EducationSchool of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China

Time-modulated array(TMA)antennas,introduce the dimension of time into antenna design to control the radiation patterns and frequency spectral characteristics,thus improve the reconfigurability of array antennas and provide multiple *** have great application potential in military and civilian fields,such as precision guidance and mobile communication,and are currently a hot spot of academic *** article provides a review on the fundamentals and applications of ***,the basic theory and mathematical formulations of TMAs are ***,the most important applications of TMAs,namely time-modulated phased arrays(TMPA),are discussed from the perspectives of harmonic suppression and harmonic utiliza-tion,which are used for single-beam and multibeam ***,we survey the combination of TMA with various types of novel antenna arrays,such as single-channel digital beamforming(DBF)arrays,frequency diverse arrays(FDAs),and retrodirective arrays,to create new hardware implementation methods and enhance their ***,recent advances in dedicated integrated chips for TMA,which have played a significant role in driving the progress of TMAs from academic research to practical applications,are ***,the challenges and prospects for TMAs are discussed,including new research directions and emerging applica-tion scenarios.

关键词： Time modulated array Phased array Single RF channel digital beam forming Frequency diversity array Retrodi-rective arrays Chips.

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钾同位素示踪地表过程:进展与挑战

矿物岩石地球化学通报 2024年第3期43卷 666-673页

作者：冯琦金章东贺茂勇中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 中国科学院大学北京100049

地表化学风化过程影响着不同时间尺度大气CO_(2)浓度和全球气候变化,因此有效示踪地表风化是表生过程研究的重要科学问题之一。钾(K)元素无化合价变化,主要赋存于硅酸盐岩中,在表生地质过程中其同位素通常会发生显著分馏,因此K同位素体... 详细信息

地表化学风化过程影响着不同时间尺度大气CO_(2)浓度和全球气候变化,因此有效示踪地表风化是表生过程研究的重要科学问题之一。钾(K)元素无化合价变化,主要赋存于硅酸盐岩中,在表生地质过程中其同位素通常会发生显著分馏,因此K同位素体系具有示踪地表过程的巨大潜力。然而,K同位素研究尚在起步阶段,其分馏机制及其控制因素等尚不清楚。本文从K的分布、主要储库的K同位素组成,以及K同位素在风化过程中的分馏行为等方面,系统总结了K同位素示踪地表过程的主要研究进展,提出了大小流域相结合、多同位素体系联用,并量化人类活动对K同位素分馏产生的影响,以此来减少K同位素示踪地表过程的不确定性的建议。

关键词：钾同位素地表过程大陆风化地球化学示踪

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Observation of gapless corner modes of photonic crystal slabs in synthetic translation dimensions

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Photonics Research 2024年第3期12卷 444-455页

作者： WEN-jin zhang HAO-CHANG MO WEN-JIE CHEN XIAO-dong CHEN JIAN-WEN dong School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China

Second-order topological photonic crystals support localized corner modes that deviate from the conventional bulk-edge ***,the frequency shift of corner modes spanning the photonic band gap has not been experimentally ***,we observe the gapless corner modes of photonic crystal slabs within a parameter space by considering translation as an additional synthetic *** corner modes,protected by topological pumping in synthetic translation dimensions,are found to exist independently of the specific corner *** gapless corner modes are experimentally imaged via the near-field scanning measurement and validated numerically by full-wave *** propose a topological rainbow with gradient translation,demonstrating the ability to extract and separate specific frequency components of light into different spatial *** work contributes to the advancement of topological photonics and provides valuable insights into the exploration of gapless corner modes in synthetic dimensions.

关键词： translation dimensions corner

Efficient removal of natural organo-chromium(Ⅲ)through selfcirculating decomplex and immobilization with nanoscale zerovalent iron

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Nano Research 2024年第1期17卷 364-371页

作者： Zhicheng dong Yunyun Xu Can Wu jin Chao Chen Tian zhang Lin School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Changsha 410083China College of Ecology and Environment Chengdu University of TechnologyChengdu 610059China School of Environment and Energy The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters(Ministry of Education)South China University of TechnologyGuangzhou 510006China

Organo-chromium(III)complex is one of the chromium contaminant species,which would transform to high-toxic Cr(VI)during migrating in the *** natural organo-chromium(III)(NOCr)is difficult to remove by traditional degradation or precipitation methods,due to its high stability and ***,we demonstrated a novel NOCr removing method by transforming it to certain structures similar to Cr-Fe minerals in nature,through a self-circulating decomplex and immobilization mechanism with nano zero-valent iron(nZVI).Taking chromium glycinate(Cr-Gly)as a probe,nZVI showed a high Cr removal efficiency of 99.4%under ambient *** removal process included three stages of adsorption,decomplexation,and ***-Gly was first adsorbed on the surface of nZVI by chemisorption of the oxide ***,the adsorbed Cr-Gly was decomplexed and oxidized to Cr(VI)by·OH and 1O_(2),which were generated from molecular oxygen activated by ***,the released Cr(VI)could be in-situ adsorbed and re-reduced to Cr(III),which was further immobilized in form of Cr-O-Fe *** the Cr-O-Fe complexing structure was similar to that of Cr-Fe minerals(such as chromohercynite)in nature,this work explored a novel and efficient NOCr removing method that was potential to weaken chromium pollution in the environment.

关键词： organo-chromium(III) zero-valent iron adsorption decomplexation Cr immobilization

Tuning mechanical and electrical performances of B_(4)C-TiB_(2)ceramics in a two-step spark plasma sintering process

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Journal of Advanced Ceramics 2024年第4期13卷 518-528页

作者： Jun Zhao Xingshuo zhang Zongning Ma dong Wang Xing jin Songlin Ran Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243002China Anhui Engineering Research Center for High Efficiency Intelligent Photovoltaic Module Chaohu UniversityHefei 238024China

B_(4)C–TiB_(2)is an advanced electrically conductive ceramic with excellent mechanical and electrical discharge machinable *** is challenging and rewarding to achieve highly conductive and hard B_(4)C–TiB_(2)composites at a minimum content of conductive TiB2 that has inferior hardness but double specific gravity of the B_(4)C matrix.A novel strategy was used to construct conductive networks in B_(4)C‒15 vol%TiB2 composite ceramics with B_(4)C,TiC,and amorphous B as raw materials by a two-step spark plasma sintering *** influences of particle size matching between B_(4)C and TiC on the conducting of the strategy and the microstructure were discussed based on the selective matrix grain growth *** mechanical and electrical properties were also systematically *** B_(4)C–15 vol%TiB2 composite ceramic prepared from 10.29µm B_(4)C and 0.05µm TiC powders exhibited a perfect three-dimensional interconnected conductive network with a maximum electrical conductivity of 4.25×10^(4)S/m,together with excellent mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 691±58 MPa,30.30±0.61 GPa,and 5.75±0.32 MPa·m^(1/2),respectively,while the composite obtained from 3.12µm B_(4)C and 0.8µm TiC powders had the best mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 827±35 MPa,32.01±0.51 GPa,and 6.45±0.22 MPa·m^(1/2),together with a decent electrical conductivity of 0.65×10^(4)S/m.

关键词： B_(4)C-TiB_(2) mechanical properties electrical conductivity conductive network

Recent advancement of sonogenetics:A promising noninvasive cellular manipulation by ultrasound

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Genes & Diseases 2024年第5期11卷 163-182页

作者： jin Tang Mingxuan Feng dong Wang Liang zhang Ke Yang Pediatric Research Institute Children’s Hospital of Chongqing Medical UniversityNational Clinical Research Center for Child Health and DisordersMinistry of Education Key Laboratory of Child Development and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChongqing Engineering Research Center of Stem Cell TherapyChongqing 400014China Department of Ultrasound The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Tongji Medical College Huazhong University of Science and TechnologyWuhanHubei 430074China

Recent advancements in biomedical research have underscored the importance of noninvasive cellular manipulation ***,a method that uses genetic engineering to produce ultrasound-sensitive proteins in target cells,is gaining prominence along with optogenetics,electrogenetics,and *** stimulation with ultrasound,these proteins trigger a cascade of cellular activities and *** traditional ultrasound modalities,sonogenetics offers enhanced spatial selectivity,improving precision and safety in disease *** technology broadens the scope of non-surgical interventions across a wide range of clinical research and therapeutic applications,including neuromodulation,oncologic treatments,stem cell therapy,and *** current literature predominantly emphasizes ultrasonic neuromodulation,this review offers a comprehensive exploration of *** discuss ultrasound properties,the specific ultrasound-sensitive proteins employed in sonogenetics,and the technique’s potential in managing conditions such as neurological disorders,cancer,and ophthalmic diseases,and in stem cell *** objective is to stimulate fresh perspectives for further research in this promising field.

关键词： Mechanosensitive channel Neuromodulation Sonogenetics Ultrasound Ultrasound-sensitive protein

Directional amine-based solvent extraction for simultaneous enhanced water recovery,salt separation and effective descaling from hypersaline brines

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 83-92页

作者： Yuyao zhang Litao Jia jin Zhao Xuming Liu Shuyu dong Chuanyang Liu Yuanyuan Cui Shougang Research Institute of Technology Beijing 100043China Research Center of Environmental Technology in Water Pollution Source Identification and Precise Supervision School of EnvironmentTsinghua UniversityBeijing 100084China

The feasibility of simultaneous water recovery,salt separation and effective descaling of hypersaline brine was investigated by diisopropylamine(DIPA)-based directional solvent extraction(DSE),using diluted/concentrated seawater with initial saline concentration range of 12–237 g/L at extraction temperatures of 5 and 15℃,*** water recovery shows an obvious boundary at saline concentration of 115 g/L under dual effect of specific water extraction efficiency and extraction *** Cl^(–) ion concentration in product water is in sharp contrast to the nearly complete removal of SO_(4)^(2–)and hardness ions,indicating that DIPA-based DSE process indeed achieved efficient separation and purification of Cl^(–) ion from hypersaline ***,the radical precipitation of Mg^(2+)and Ca^(2+)ions in form of Mg(OH)_(2)and CaCO_(3)demonstrates effective descaling potential,although it leads to more DIPA residues in dewatered raffinate than product ***,an exponential correlation between the Cl^(–) removal efficiency and specific water extraction efficiency further reveals the intrinsic relationship of water extraction process and transfer of Cl^(–) ion to the product ***,the study provides a novel approach for integrating the water recovery and separation of Cl^(–) ion from ultra-high-salinity brines with radical precipitation of Mg^(2+)and Ca^(2+) ions in one step.

关键词： Hypersaline brines Directional solvent extraction Salt separation Ca^(2+)and Mg^(2+)descaling

Morphology evolution of two-phase Cu-Ag alloys under different conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 458-463页

作者： jin-li HU jin-dong zhang Liang MENG Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China Xingtai Xinhui Copper Special Wire. Co. Ltd. Xingtai 055550 China

有不同 Ag 内容的 Cu-Ag 细丝的微 composites 被冷绘画和中间的热处理准备。微观结构描述和细丝的分发在不同条件下面为二阶段的合金被观察。Cu-Ag 合金的微观结构进化上的重绘画紧张的效果被调查。微观结构部件由 Cu 树突，最容易溶... 详细信息

有不同 Ag 内容的 Cu-Ag 细丝的微 composites 被冷绘画和中间的热处理准备。微观结构描述和细丝的分发在不同条件下面为二阶段的合金被观察。Cu-Ag 合金的微观结构进化上的重绘画紧张的效果被调查。微观结构部件由 Cu 树突，最容易溶解的殖民地和第二等的 Ag 组成的结果表演在包含 6%∼24%( 集体部分) 的合金猛抛 Ag。随 Ag 内容的增加，在微观结构的最容易溶解的殖民地增加并且逐渐地变成连续网状的分布。Cu 树突，最容易溶解的殖民地和第二等的 Ag 猛抛在一个轴的方向被伸长并且在冷绘画期间发展成合成细丝的结构变丑。最容易溶解的殖民地趋于演变为细丝的捆。细丝的直径随为二阶段的合金拉紧张度的增加减少，特别地为有低 Ag 内容的合金。一旦绘画紧张超过了某个水平，在细丝的直径的减小变得慢。

关键词：高锰酸钾氯锰去除钱塘江源头

Programmable repulsive potential for tight-binding from Chen-Möbius inversion theorem

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 71-83页

作者： Jian-Gao Li jin-Kun Tang Hong-Quan Song Gotthard Seifert dong-Bo zhang College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875China Department of Physics Beijing Normal UniversityBeijing 100875China College of Physics and Telecommunication Engineering Zhoukou Normal UniversityZhoukou 466001China Theoretische Chemie Technische Universität DresdenDresden D-01062Germany

An accurate total energy calculation is essential in materials *** date,many tight-binding(TB)approaches based on parameterized hopping can produce electronic structures comparable to those obtained using first-principles ***,TB approaches still have limited applicability for determining material properties derived from the total *** is,the predictive power of the TB total energy is impaired by an inaccurate evaluation of the repulsive *** complexity associated with the parametrization of TB repulsive potentials is the weak link in this *** this study,we propose a new method for obtaining the pairwise TB repulsive potential for crystalline materials by employing the Chen-Möbius inversion *** show that the TB-based phonon dispersions,calculated using the resulting repulsive potential,compare well with those obtained by first-principles calculations for various systems,including covalent and ionic bulk materials and twodimensional *** present approach only requires the first-principles total energy and TB electronic band energy as input and does not involve any *** striking feature enables us to generate repulsive potentials programmatically.

关键词： tight binding first-principles calculation total energy repulsive potential phonon dispersion