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CPL-active hybrid copper(Ⅰ) halides enabled by cation inclusion with chiral crown-ether

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Science China Chemistry 2024年第10期67卷 3283-3290页

作者： peng Fan Li-xuan Cai xiao-Fang Duan Fan Yin Chen-Chen Li Zhong-Hua Deng xiao-Zhen Li Qing-Fu Sun College of Chemistry and Materials Science Fujian Normal University State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences Fujian College University of Chinese Academy of Sciences Strait Institute of Flexible Electronics (Future Technologies) Fujian Key Laboratory of Flexible ElectronicsFujian Normal University and Strait Laboratory of Flexible Electronics

Chiral hybrid metal halides with high photoluminescence quantum yield（PLQY） and superior dissymmetry factor(glum) are promising candidates for circularly polarized luminescence（CPL） emitting ***,it is a great challenge to achieve both high glumand large ***,we report a new supramolecular strategy to fabricate chiral hybrid Cu（Ⅰ）-halides with nearunity quantum yields and intense CPL *** dissymmetry factor can be dramatically modulated by tuning the hostguest *** to the chirality and variable conformations of the host-guest complexes,a series of chiral[G@LR/S]2Cu4I6have been *** incorporation of different cations within the chiral LR/Shosts leads to variations of packing modes along the c-axis and different extent of distortions in the[Cu4I6]*** them,[H3O@LR/S]+cations are stacked based on Van der Waals interactions and hierarchically self-assemble into a right/left-handed helix in[H3O@LR/S]2Cu4I6,which results in a high glumof-7×10-3and a large PLQY of 96.92%.Notably,[G@LR/S]2Cu4I6shows promising applications in single-component white light emitting diodes（WLEDs）,exhibiting a maximum dissymmetry factor of -1.2×*** effective host-guest complexation and oriented hierarchical self-assembly provide an effective strategy for the development of high-performance CPL materials.

关键词： host-guest interaction circularly polarized luminescence copper iodide cluster hierarchical self-assembly chirality

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高氯酸根及其离子对光谱指认的量子化学研究

光谱学与光谱分析 2010年第9期30卷 2537-2540页

作者：轩小朋谢友海赵扬河南师范大学化学与环境科学学院河南新乡453007

利用红外和拉曼光谱研究了不同浓度下高氯酸锂在N,N-二甲基甲酰胺、乙腈、四氢呋喃、丙酮、二甲亚砜、乙酸甲酯等有机溶剂中的缔合情况,分析了高氯酸根ν1谱带的变化,指认了溶液中光谱自由离子、直接接触离子对和离子对二聚体。使用量... 详细信息

利用红外和拉曼光谱研究了不同浓度下高氯酸锂在N,N-二甲基甲酰胺、乙腈、四氢呋喃、丙酮、二甲亚砜、乙酸甲酯等有机溶剂中的缔合情况,分析了高氯酸根ν1谱带的变化,指认了溶液中光谱自由离子、直接接触离子对和离子对二聚体。使用量子化学方法计算了不同结构直接接触离子对和离子对二聚体的稳定构型和光谱行为,并和实验值进行了比较,考察了溶剂化模型、溶剂分子对直接接触离子对或离子对二聚体结构的影响,探讨了量子化学方法指认离子对的可能性和正确性。

关键词：高氯酸根离子缔合直接接触离子对离子对二聚体振动光谱

Characterization of size-resolved effective density of atmospheric particles in an urban atmosphere in Southern China

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Journal of Environmental Sciences 2024年第7期141卷 194-204页

作者： Tingting Xie Liming Cao Jinyi Zheng peng xuan xiaofeng Huang Laboratory of Atmospheric Observation Supersite School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China

Effective density(ρ_(eff))is one of the most important physical properties of atmospheric particles,providing important references in exploring the emissions and aging processes of fresh *** this study,a combined system of differential mobility analyzer,centrifugal particle mass analyzer,and condensation particle counter was used to periodically measure theρ_(eff)of atmospheric particles in Shenzhen from Oct.2021 to *** showed that theρ_(eff)of particles with various size presented a bimodal distribution,which could be divided into main density(ρ_(m),main peak,corresponding to relatively dense particles after aging)and sub density(ρ_(s),sub peak,corresponding to fresh particles).The occurrence frequencies ofρ_(s)of particles with diameters of 50 and 80 nm were less than 20%,but were as high as about 40%of that with diameters from 120 to 350 ***ρ_(m)showed increasing trend with the size of particles,whileρ_(s)decreased as the increasing of the size of ***ρ_(eff)on pollution day varied significantly with chemical *** increasing of the proportion of sulfate could promote the increasing ofρ_(eff),while black carbon and organic matter caused opposite effects,which may be related to various factors,including the difference of the material density and morphology of various chemical ***ρ_(eff)of 50,80 and 120 nm particles decreased considerably during the new particle formation event,indicating that organic condensation was an important contributor to new particle growth.

关键词： DMA-CPMA-CPC Effective density Main/sub density Size distribution

Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains,China

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Journal of Forestry Research 2024年第3期35卷 197-208页

作者： Jinkuan Li Jianfeng peng xiaoxu Wei Meng peng xuan Li Yameng Liu Jiaxin Li College of Geography and Environmental Science Henan UniversityKaifeng 475004People’s Republic of China Key Laboratory of Earth System Observation and Simulation of Henan Province Kaifeng 475004People’s Republic of China

Global warming will affect growth strategies and how trees will *** compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and treering chronologies developed on northern and western slopes from the Lubanling in the Funiu *** analyses showed that two chronologies were mainly limited by temperatures in the previous June–August and the combination of temperatures and moisture in the current May–*** difference of the climate response to slopes was small but not *** growth of the LBL01 site on the northern slope was affected by the combined maximum and minimum temperatures,while that of the LBL02 site was affected by maximum *** regards to moisture,radial growth of the trees on the north slope was influenced by the relative humidity in the current May–July,while on the western slope,it was affected by the relative humidity in the previous June–August,the current May–July and the precipitation in the current May–*** the change in climate,the effects of the main limiting factors on growth on different slopes were visible to a certain extent,but the differences in response of trees on different slopes gradually decreased,which might be caused by factors such as different slope directions and the change in diurnal temperature *** results may provide information for forest protection and ecological construction in this region,and a scientific reference for future climate reconstruction.

关键词： Tree ring width Lubanling Pinus armandii Franch Slope direction Climate response

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Holographic Polymer Nanocomposites with High Refractive Index Modulation by Doping Liquid Crystal E6M

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Chinese Journal of Polymer Science 2024年第7期42卷 926-935,I0006页

作者： Meng-Yun Wang Yue Zhang Dan Wang Ming Yao Yi-xuan Wang Xing-Ping Zhou Hai-Yan peng xiao-Lin Xie Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China National Anti-counterfeit Engineering Research Center Huazhong University of Science and TechnologyWuhan430074China

Holographic optical elements(HOEs)based on polymer composites have become a research hot spot in recent years for augmented reality(AR)due to the significant improvement of optical performance,dynamic range,ease of processing and high yield ***,it remains a formidable challenge to obtain a large field of view(FOV)and brightness due to the limited refractive index ***,we report an effective method to tackle the challenge by doping an epoxy liquid crystal termed E6M,which enables a large refractive index modulation of 0.050@633 nm and low haze of 5.0%at a doping concentration of 5 wt%.This achievement may be ascribed to the improved molecular ordering of liquid crystals within the holographic polymer *** high refractive index modulation can endow transmission-type holographic polymer composites with a high diffraction efficiency of 96.2%at a small thickness of 5μm,which would promise the design of thin and lightweight AR devices.

关键词： Polymer nanocomposites Holography AR/VR Refractive index modulation Liquid crystal

Realizing high initial Coulombic efficiency in manganese-based layered oxide cathodes for sodium-ion batteries via P2/O'3 biphasic structure optimization

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Rare Metals 2024年第5期43卷 2093-2102页

作者： Bo peng Zi-Hao Zhou Ping xuan Jie Xu Lian-Bo Ma School of Materials Science and Engineering Anhui University ofTechnologyMa'anshan 243002China Anhui Product Quality Supervision&Inspection Research Institute Hefei 230051China

Mn-based layered oxides are among the most promising cathode materials for sodium-ion batteries owing to the advantages of abundance,environmenta friendliness,low cost and high specific capacity.P2 and O'3 are two representative structures of Mn-based layered ***,the P2 structure containing insufficien Na generally exhibits low initial charge capacity,while O'3structure with sufficient Na delivers high initial charge capacity but poor cycle *** study prepared a multitude of Na_(x)MnO_(2)(x=0.7,0.8,0.9)cathode materials with varying P2/O'3 ratios and further investigated their electrochemical *** optimized Na_(0.8)MnO_(2) comprising 69.9 wt%O'3 and 30.1 wt%P2 phase,exhibited relatively balanced specific capacity,Coulombic efficiency and cycle ***,it achieved a high specific capacity of 128.9 mAh·g^(-1) with an initia Coulombic efficiency of 98.2%in half-cell configuration The Na_(0.8)MnO_(2)//hard carbon full cell also achieved a high specific capacity of 126.7 mAh·g^(-1) with an initia Coulombic efficiency of 98.9%.Moreover,the capacity fading mechanism was revealed by combining in-situ and ex-situ X-ray *** findings of this study provide theoretical guidance for further modification design of Mnbased layered cathodes.

关键词： Sodium-ion batteries Cathode materials Mn-based layered oxides P2/0'3 composites

Effects of long-term fencing on soil microbial community structure and function in the desert steppe,China

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Journal of Arid Land 2024年第3期16卷 431-446页

作者： PAN Yaqing KANG peng QU xuan RAN Yichao LI Xinrong Shapotou Desert Research and Experiment Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Biological Science and Engineering North Minzu UniversityYinchuan 750021China

One of the goals of grazing management in the desert steppe is to improve its ***,relatively little is known about soil microbe communities in the desert steppe ecosystem under grazing *** this study,we investigated the diversity and aboveground biomass of Caragana korshinskii *** communities in long-term fencing and grazing areas,combined with an analysis of soil physical-chemical properties and genomics,with the aim of understanding how fence management affects plant-soil-microbial inter-relationships in the desert steppe,*** results showed that fence management(exclosure)increased plant diversity and aboveground biomass in *** shrub area and effectively enhanced soil organic carbon(233.94%),available nitrogen(87.77%),and available phosphorus(53.67%)*** well,the Shannon indices of soil bacteria and fungi were greater in the fenced ***-soil changes profoundly affected the alpha-and beta-diversity of soil *** management also altered the soil microbial community structure,significantly increasing the relative abundances of Acidobacteriota(5.31%-8.99%),Chloroflexi(3.99%-5.58%),and Glomeromycota(1.37%-3.28%).The soil bacterial-fungal co-occurrence networks under fence management had higher complexity and *** on functional predictions,fence management significantly increased the relative abundance of bacteria with nitrification and nitrate reduction functions and decreased the relative abundance of bacteria with nitrate and nitrite respiration *** relative abundances of ecologically functional fungi with arbuscular mycorrhizal fungi,ectomycorrhizal fungi,and saprotrophs also significantly increased under fence *** addition,the differential functional groups of bacteria and fungi were closely related to plant-soil *** results of this study have significant positive implications for the ecological restoration and reconstruction of dry desert steppe and simila

关键词： desert steppe fence management Caragana korshinskii soil physical-chemical property soil microorganism

The Role of Renewable Protocatechol Acid in Epoxy Coating Modification: Significantly Improved Antibacterial and Adhesive Properties

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Chinese Journal of Polymer Science 2024年第1期42卷 63-72,I0008页

作者： Ming-xuan Chen Jin-Yue Dai Li-Yue Zhang Shuai-peng Wang Jing-Kai Liu Yong-Gang Wu Xin-Wu Ba xiao-Qing Liu School of Chemistry and Materials Science Hebei UniversityBaoding 071000China Ningbo Institute of Materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China Key Laboratory of Marine Materials and Related Technologies Chinese Academy of SciencesNingbo 315201China

It is of great significance to design epoxy coatings with superior antibacterial properties and high adhesive properties, as well as excellent processing, superior durability, and high transparency. However, it is still a challenge because of the common complex design and synthesis. Herein, the bio-based monomer protocatechuic acid(PCA) was used as raw material, the catechol structure with high bonding and antibacterial properties was introduced into the flexible alkane segment of ethylene glycol diglycidyl ether(EGDE) through an efficient, and green method, and it was cured with isophorone diamine(IPDA) to prepare corresponding thermosets. The cured resins exhibited excellent allaround qualities, particularly in bonding and antibacterial. When 30% PCA was added to pure epoxy resin, the adhesion between substrate and coating increased from 4.40 MPa to 13.60 MPa and the antibacterial rate of coating against E. coli and S. aureus could approach 100%. All of this is due to the fact that the catechol structure present in PCA has the ability to interact with various substrates and alter the permeability of bacterial cell membranes. The architecture of this method offers a fresh approach to dealing with the issues of challenging raw material selection and complex synthesis techniques.

关键词： Epoxy coatings Thermosets Catechol structure Antibacterial High adhesion

mRNA vaccine technology for infectious diseases and beyond

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Science China Life Sciences 2024年第10期67卷 2267-2270页

作者： Pei Hao xiao Li xuan Li Wu Zhong Key Laboratory of Molecular Virology and Immunology Shanghai Institute of Immunity and InfectionChinese Academy of Sciences University of Chinese Academy of Sciences Changchun Veterinary Research Institute Chinese Academy of Agricultural Sciences Key Laboratory of Synthetic Biology CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of Sciences National Engineering Research Center for the Emergency Drug Beijing Institute of Pharmacology and Toxicology

The rise of mRNA vaccine technology Vaccines stand as one of the most significant medical advancements, playing a crucial role in the prevention of infectious diseases and the improvement of global health. The triumph of smallpox vaccination stands as a towering achievement in the annals of healthcare, leading to the complete elimination of a oncedevastating disease and showcasing the efficacy of vaccination methods.

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