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Chinese Journal of Chemistry 2023年第13期41卷 1566-1574页

作者： Han Yi Yuesheng Li Dong-po song Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin300350 China

Organized spontaneous emulsification (OSE) produces ordered water-in-oil-in-water (W/O/W) multiple emulsion droplets stabilized by bottlebrush block copolymer (BBCP) surfactants, such as (polynorbornene-g-polystyrene)-b-(polynorbornene-g-polyethylene oxide) (PS-b-PEO), templating ordered porous particles with visible structural colors. Here, homopolymer polystyrenes (hPS) were used to swell the PS domain and thus to effectively increase the W/O interfacial curvature of the internal droplets. By variation of hPS concentration, pore diameter is largely tunable from 34 to over 210 nm, leading to tunable photonic bandgaps in the whole visible spectrum. The ratio (α) of molecular weight of hPS relative to that of the PS side chains of the BBCP can greatly influence their spatial distribution within the PS domain. For α ≤ 1, uniform solubilization of the hPS chains into the side chains of BBCP is achieved leading to a homogeneous porous structure. For α > 1, local solubilization of the hPS chains at interface of the internal droplets is disclosed at relatively low concentrations of hPS (≤ 42 wt%), resulting in a small change in pore diameter. For contrast, a rapid increase of the W/O interfacial curvature was observed upon further increase of the hPS content (> 42 wt%) through an evident influence on the OSE procedure.

关键词： Block copolymer Self-assembly porous polymers Copolymers Microstructures

An experimental study of in-plane arch-shaped dampers

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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 849-867页

作者： Chien-Liang Lee Yen-po Wang Meng-yan Cai School of Civil Engineering and Architecture Xiamen University of Technology Xiamen 361024 Fujian China Department of Civil Engineering Chiao-Tung University Hsinchu 30010 Chinese Taipei

As an effort to minimize material utilization, seismic steel dampers designed to deform inelastically in an in-plane flexural mode have attracted serious attention recently. This paper presents a new type of metallic yielding damper referred to as the in-plane arch-shaped damper modified from its portal frame-shaped counterpart by replacing the straight beam with a circular arch to minimize the effects of stress concentration and warping, and therefore to avoid premature failure. Component tests of both the portal frame-shaped and arch-shaped in-plane dampers were conducted for comparison. Hysteresis loops obtained from the component tests under cyclic loads indicate substantial improvement on the energydissipative characteristics of the proposed damper. Moreover, seismic performance assessment of the proposed damper was carried out further via shaking table tests of a five-story model frame. Encouraging results have been achieved in terms of acceleration reduction, damping enhancement and peak suppression of the frequency response functions, suggesting the potential of the proposed device to be used in earthquake-resisting systems.

关键词： seismic metallic yielding damper in-plane arch-shaped damper hysteresis loop shaking table test

Relationship Between Individuals’Epidemic Risk Perception Within Living Space and Subjective Well-Being:Empirical Evidence from China after the First Wave of COVID-19

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Chinese Geographical Science 2024年第2期34卷 369-382页

作者： song Jiangyu ZHOU Suhong KWAN Mei-po ZHENG Zhong School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China Guangdong Provincial Engineering Research Center for Public Security and Disaster Guangzhou 510275China Institute of Space and Earth Information Science the Chinese University of Hong KongHong Kong 999077China Department of Geography and Resource Management the Chinese University of Hong KongHong Kong 999077China Institute of Future Cities the Chinese University of Hong KongHong Kong 999077China Center for Territorial Spatial Planning and Real Estate Studies Beijing Normal UniversityZhuhai 519000China

It is common to observe the epidemic risk perception(ERP)and a decline in subjective well-being(SWB)in the context of public health events,such as Corona Virus Disease 2019(COVID-19).However,there have been few studies exploring the impact of individuals’ERP within living space on their SWB,especially from a geographical and daily activity perspective after the resumption of work and other activities following a wave of the *** this paper,we conducted a study with 789 participants in urban China,measuring their ERP within living space and examining its influence on their SWB using path *** results indicated that individuals’ERP within their living space had a significant negative effect on their *** density of certain types of facilities within their living space,such as bus stops,subway stations,restaurants,fast food shops,convenience shops,hospitals,and public toilets,had a significantly negative impact on their SWB,mediated by their ERP within living ***,participation in out-of-home work and other activities not only increased individuals’ERP within living space,but also strengthened its negative effect on their SWB.

关键词： subjective well-being epidemic risk perception living space the density of facilities out-of-home activities

Theoretical Study on Photoisomerization of 2-Methylfuran to 3-Methylfuran

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Chinese Journal of Structural Chemistry 2006年第6期25卷 681-688页

作者： WANG yan-Xia YE song Department of Chemistry Yunnan University Kunming 650091 China

In the present work, the photoisomerization of 2-methylfuran to 3-methylfuran is investigated with the complete active space SCF （CASSCF） molecular orbital method. Geometries of minima and transition states on the excited and ground states are fully optimized at the CAS level with a 6-3 IG＊ basis set. A multireference MP2 algorithm that has been implemented in Gaussian is used to correct the energetics for dynamic correlation. The topology and reaction funnels of the singlet, triplet （S0, T1, T2） and potential energy surfaces have been characterized along the reaction coordinates corresponding to the mechanism. The reaction proceeds via two diradical intermediates, one intermediate product and four transition states. The two diradical S 1/T2 and T1/S0 energy surface crossing points are located along the reaction path and a T1/T2 conical intersection is also located. From this point the reaction soon returns to T1 surface. It is the most reasonable that the intersystem crossing from T1 to S0 takes place.

关键词： CASSCF photoisomerization intersystem crossing point reaction path

Theoretical Study on the Triplet-sensitized Photolysis of 2,5-Dimethylfuran

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1145-1151页

作者： WANG yan-Xia YE song Department of Chemistry Yunnan University Kunming 650091 China

In the present work, the triplet-sensitized photolysis of 2,5-dimethylfuran has been investigated with the complete active space SCF （CASSCF） molecular orbital method. Two different reaction routes through diradical and carbene intermediates respectively have been systematically studied, and the reaction via carbene intermediate is the major part well compatible with experiment. Geometries of minima and transition states on S0T1 surface were fully optimized at the CAS level with a 6-31G^＊ basis set. A multireference MP2 algorithm that has been implemented in Gaussian was used to correct the energetics for dynamic correlation. Four intersystem crossing points have been located and discussed, and two of them are efficient. Our computation indicates that the reaction must occur on the triplet-excited state.

关键词： CASSCF photolysis intersystem crossing point reaction path

possible Involvement of Reactive Oxygen Species Scavenging Enzymes in Desiccation Sensitivity of Antiaris toxicaria Seeds and Axes

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Journal of Integrative Plant Biology 2008年第12期50卷 1549-1556页

作者： Hong-yan Cheng song-Quan song Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

The relationships among desiccation sensitivities of Antiaris toxicaria seeds and axes, changes in activities of superoxide dismutase （SOD）, ascorbate peroxidase （APX）, catalase （CAT）, glutathione reductase （GR） and dehydroascorbate reductase, （DHAR）, production rate of superoxide radical （.O2^-）, and the contents of hydrogen peroxide （H2O2） and thiobarbituric acid （TBA）-reactive substance were studied. Desiccation tolerance of seeds and axes decreased with dehydration. Desiccation tolerance of axes was higher than that of seeds, and that of epicotyls was higher than radicles. Activities of SOD, CAT and DHAR of seeds increased during the initial phase of dehydration, and then decreased with further dehydration, whereas activities of APX and GR decreased with dehydration. These five enzyme activities of axes, however, increased during the initial phase of dehydration, and then decreased with further dehydration. The rate of superoxide radical production, and the contents of H2O2 and TBA-reacUve products of seeds and axes gradually increased with dehydration. These results show that the A. toxicaria seed is a typical recalcitrant seed. Loss of desiccation tolerance in seeds and axes was correlated with the increase in .O2- production rate, content of H2O2 and TBA-reactive products, and the decline of antioxidant enzyme activities of seeds and axes.

关键词： Antiaris toxicaria antioxidant enzyme content of H2O2 and thiobarbituric acid-reactive product O2^- production rate recalcitrant seed.

Species and Organ Diversity in the Effects of Hydrogen Peroxide on Superoxide Dismutase Activity In Vitro

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Journal of Integrative Plant Biology 2006年第6期48卷 672-678页

作者： Hong-yan Cheng song-Quan song Xishuangbanna Tropical Botanical Garden the Chinese Academy of Sciences Mengla Yunnan 666303 China Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

Superoxlde dlsmutase （SOD） is ubiquitous in aerobic organisms and constitutes the first link In the enzyme scavenging system of reactive oxygen species. In the present study, species and organ diversity of SOD activity In a solution and In an in-gel assay system, as well as the effects of hydrogen peroxide （H202） on SOD activity, were Investigated. In a solution assay system, SOD activity of jackfruIt root, shoot, leaves, axes, and cotyledons, of maize embryos and endosperms, of mung bean leaves and seeds, of sacred lotus axes and cotyledons, and of rice and wheat leaves was Increased by 1-15 mmol/L H2O2. However, SOD activity In rice root and seeds, maize roots and leaves, mung bean roots and shoots, and wheat seeds was decreased by 1-15 mmol/L H2O2. The SOD activity of wheat root and soybean roots, leaves, axes, and cotyledons was Increased by 1-4 mmol/L H2O2, but was decreased by concentrations of H2O2 〉4 mmol/L. The SOD activity of soybean shoots was not affected by 1-15 mmol/L H2O2. The SOD activity In crude mltochondrla of jackfruIt, maize, and upas seeds, as well as In purified mitochondria of jackfruIt, was also Increased by 1-15 mmol/L H2O2. In the In-gel assay system, the SOD In jackfruIt cotyledons was comprised of Mn-SOD, Cu/Zn-SOD, and Fe-SOD, the crude mltochondria of jackfruit seeds and maizes embryo was comprised of Mn-SOD and Cu/ Zn-SOD, and the crude mltochondria of maize seeds was comprised of Mn-SOD only. In the present study, H2O2 markedly Inhibited Cu/Zn-SOD and Fe-SOD activity.

关键词： hydrogen peroxide inhibitor informative in-gel assay system solution assay system species and organ diversity superoxide dismutase activity.

A TVD Type Wavelet-Galerkin Method for Hamilton-Jacobi Equations

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 303-310页

作者： Ling-yan Tang song-he song Department of Mathematics and System Science Science School National University of Defense Technology Hunan 410073 China

In this paper, we use Daubechies scaling functions as test functions for the Galerkin method, and discuss Wavelet-Galerkin solutions for the Hamilton-Jacobi equations. It can be proved that the schemes are TVD schemes. Numerical tests indicate that the schemes are suitable for the Hamilton-Jacobi equations. Furthermore, they have high-order accuracy in smooth regions and good resolution of singularities.

关键词： Hamilton-jacobi equation wavelet-galerkin method daubechies wavelet TVD method

Properties of off-axis hollow Gaussian–Schell model vortex beam propagating in turbulent atmosphere

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Chinese Physics B 2020年第6期29卷 230-236页

作者： yan-song song Ke-yan Dong Shuai Chang yan Dong Lei Zhang National and Local Joint Engineering Research Center of Space Optoelectronics Technology Changchun University of Science and TechnologyChangchun 130022China

The analytical expression of off-axis hollow Gaussian–Schell model vortex beam(HGSMVB)generated by anisotropic Gaussian–Schell model source is first *** evolution properties of off-axis HGSMVB propagating in turbulent atmosphere are *** results show that the off-axis HGSMVB with smaller coherence length or propagating in stronger turbulent atmosphere will evolve from dark hollow beam into Gaussian-like beam with a larger beam spot *** beams with different values of integer order N or the position for hollow and vortex factor R will have almost the same Gaussian-like spot distribution at the longer propagation distance.

关键词： vortex beam off-axis beam Gaussian-Schell model sources laser propagation intensity

Comparative study of performance comparison of AlSi10Mg alloy prepared by selective laser melting and casting

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Journal of Materials Science & Technology 2020年第6期41卷 199-208页

作者： Qian yan Bo song Yusheng Shi State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China

The influence of the microstructure on mechanical properties of AlSi10Mg fabricated by casting and selective laser melting(SLM)were investigated and contrasted in this work,with an emphasis on understanding the forming *** microstructure,phase structure and mechanical properties were characterized by scanning electron microscopy/field-emission Transmission Electron Microscopy(SEM/TEM),X-Ray Diffraction(XRD),tensile and fatigue *** results indicated that the SLM AlSi10Mg exhibited a supersaturated Si network structure precipitated alongα-Al ***β-Al5FeSi andπ-Al8FeMg3Si6 phases were found in the as-cast and SLM AlSi10Mg respectively due to different thermal histories during *** SLM AlSi10Mg showed higher tensile strength but lower elongation than the casting,as the result of grain refinement and tortuous crack *** fatigue results revealed that unmelted powder,oxide inclusion and pores can considerably degrade the fatigue properties for the SLM *** SLM process offered a new method for material processing that would avoid harmful Fe-bearing intermetallic compounds and refine the microstructures for enhancing strength.

关键词： Selective laser melting Casting AlSi10Mg Intermetallic compound Mechanical properties