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Lactonization of dyes promoted by a coordination cage facilitates cavity-induced chromism as ion mobile detector

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Science China Chemistry 2024年第5期67卷 1554-1560页

作者： Liangliang Zhang Yu Liang Zhifeng Xiao Yuxuan meng Jinyi Huang Xi Lin Ji Li Hong-Cai Zhou Yu fang Strait Institute of Flexible Electronics(SIFE Future Technologies)Fujian Normal University and Strait Laboratory of Flexible Electronics(SLoFE)Fuzhou 350017China State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China Department of Chemistry Texas A&M UniversityCollege StationTexas 77842-3012USA State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Frontiers Science Center for Flexible Electronics(FSCFE) MIIT Key Laboratory of Flexible Electronics(KLoFE)Northwestern Polytechnical UniversityXi’an 710072China

Dye molecules often change colors(so-called “chromism”) according to the environment variation. However, they are rarely induced by a catalytic amount of cavity. Through encapsulation in the cavity of a porous coordination cage(PCC-2), Rhodamine B(1) is transformed from red quinonoid form(1q) into colorless lactone form(1l) in aprotic polar solutions. The μ4-OH groups in the cavity of PCC-2 are shown to stabilize the uncommon zwitterion intermediate(1z), followed by converting to 1l, thus accelerating the equilibrium. The chromism is catalyzed by 0.25 mol% of PCC-2, and the reaction rate is improved by 80,400times. 1@PCC-2 can be further fabricated to a sol-gel that exhibits ion recognition properties. The resulting encapsulation and stabilization of an unconventional intermediate by a catalytic amount of the coordination cage provides fundamental insights into molecular isomerization and has potential use in chemical sensing.

关键词： porous coordination cage Zwitterion intermediate cavity Rhodamine B chromism

Carbon and oxygen isotopes analyses for the Sinian carbonates in the Helan Mountain, North China

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Chinese Science Bulletin 2013年第4期58卷 3943-3955页

作者： YANG Jie ZENG ZuoXun CAI XiongFei LI ZhiYong LI TianBin meng fang HE WenJian Faculty of Earth Sciences China University of Geosciences Three Gorges Geotechnical Consultants Co. Ltd. Huazhong Tectonomechanical Research Center Ningxia Monitoring Institute of Land Resources Survey Ningxia Institute of Geological Survey Geological Team 292 of the Guangdong Province Nuclear Industry Geological Bureau

We conducted detailed studies of the Sinian carbonates from the Helan Mountain,Ningxia by both field investigation and laboratory analyses of carbon and oxygen *** carbon isotopic compositions of the Sinian Zhengmuguan Formation shows variations with regularity in the five studied sections,theδ13C values all gradually decrease from bottom to top,with a total range from 4.51‰to 0.11‰,and the biggest negative excursion reaches up to 6.88‰.In addition,abundant macro-body fossils were also found from the Tuerkeng Formation in this study,similar to those found from the Dengying Formation in the South China *** observation firmly constrained the age for the Zhengmuguan and Tuerkeng formations to the Sinian *** we interpreted that the Zhengmuguan Formation formed during a glacial period when the extremely cold climate substantially decreased the amount of burial of organic matter in the ocean and thus led to the general negativeδ13C *** increasingδ13C values in the Tuerkeng Formation dolomites imply the ending of the glacial period in the Zhengmuguan epoch,biological recovery and increase of organic matter burial in the ocean occurred during this *** our obtained carbon and oxygen isotopes of the Zhengmuguan and Tuerkeng formations with those of coeval carbonate successions from other places all over the world,the Zhengmuguang-aged glacial deposits might be deposited after the Gaskiers *** study provides important information for paleo-ocean,paleogeographic and biological evolution in the North China Block during the Ediacaran period and adds new carbon and oxygen isotopes data for the global Sinian carbon-oxygen isotopes dataset.

关键词：氧同位素分析中国北方碳酸盐震旦系贺兰山冰川沉积物碳同位素组成生物恢复

Pillar[5]arene based artificial light-harvesting supramolecular polymer for efficient and recyclable photocatalytic applications

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Chinese Chemical Letters 2024年第9期35卷 179-182页

作者： Lei Zhou Youjun Zhou Lizhen fang Yiqiao Bai Yujia meng Liang Li Jie Yang Yong Yao School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai 201418China School of Chemistry and Chemical Engineering Nantong City Key Laboratory of Life-Organic ChemistryNantong UniversityNantong 226019China College of Science Nanjing Forestry UniversityNanjing 210037China

Photosynthesis is the process through which living plants utilize photosynthetic pigments,such as chlorophyll,to convert CO_(2)and water into organic compounds and release O_(2)under visible *** this study,we have successfully constructed a fluorescent supramolecular polymer(P5Py_(2)/Zn/Gen)n by employing orthogonal pillar[5]arene-based molecular recognition and metal ion *** the supramolecular polymer,the guest molecule Gen unit acts as a light-harvesting moiety,as the ACQ effect is inhibited by host-guest interactions,while the(Py)_(2)/Zn center serves as a catalytic *** employing this orthogonal self-assembly strategy,we have enhanced the stability of both the donor and acceptor in catalyzing the reduction of p-nitrophenol to ***,this photocatalyst can be reused at least 5 times without significant conversion *** findings provide a pathway for constructing a recyclable artificial LHS that mimics the entire photosynthesis process.

关键词： Pillararenes Light-harvest Supramolecular polymer Photosynthesis Orthogonal self-assembly

Omicron adopts a different strategy from Delta and other variants to adapt to host

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Signal Transduction and Targeted Therapy 2022年第3期7卷 616-618页

作者： Xiaohong Du Haijun Tang Long Gao Zhao Wu fang meng Ruhong Yan Shigang Qiao Jianzhong An Chen Wang F.Xiao-Feng Qin Institute of Clinical Medicine Research Affiliated Suzhou Science and Technology Town Hospital of Nanjing Medical UniversitySuzhou 215153China Institute of Systems Medicine Chinese Academy of Medical Sciences&Peking Union Medical CollegeSuzhou Institute of Systems MedicineSuzhou 215123China Deportment of Infectious Disease The First Affiliated Hospital of Anhui Medical UniversityHefei 230000China

Dear Editor,With the ongoing of Corona Virus Disease 2019(COVID-19)epidemic,new strains of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)are continuously *** Delta(B.1.617.2)identified in India,Lambda(C.37),Mu(B.1.621),and Omicron(B.1.1.529)were successively found in Peru,Colombia,and Botswana/South Africa,and subsequently defined as variant of interest(VOI)or variant of concern(VOC).

关键词： acute respiratory Delta

基于LOD控制与内外存调度的大型三维点云数据绘制

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计算机辅助设计与图形学学报 2006年第1期18卷 1-8页

作者：孟放查红彬中国传媒大学信息工程学院北京100024 北京大学视觉与听觉信息处理国家重点实验室北京100871

通过结合基于视点的细节层次(level-of-detail,LOD)控制技术和内外存调度的数据控制策略,实现大型三维点云数据在一般配置PC机上的实时交互浏览.首先将输入点云分为大小相等的若干块,然后对每块数据分别建立误差控制下的多分辨率数据结... 详细信息

通过结合基于视点的细节层次(level-of-detail,LOD)控制技术和内外存调度的数据控制策略,实现大型三维点云数据在一般配置PC机上的实时交互浏览.首先将输入点云分为大小相等的若干块,然后对每块数据分别建立误差控制下的多分辨率数据结构,并进行内外存分配.在交互绘制中,通过用户视点来确定当前的感兴趣区域,以控制模型表面的细节层次分布.该算法不但可以实现大型点云数据的实时交互绘制,而且可有效地提高一般点云数据绘制时的内存使用效率.

关键词：大型三维点云数据交互绘制基于视点的细节层次控制内外存调度

Assessment of water level threshold for groundwater restoration and over-exploitation remediation the Beijing-Tianjin-Hebei Plain

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Journal of Groundwater Science and Engineering 2022年第2期10卷 113-127页

作者： Hui-feng Yang Rui-fang meng Xi-lin Bao Wen-geng Cao Ze-yan Li Bu-yun Xu Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China National Field Scientific Observation and Research Station on Groundwater and Ground Subsidence in the Plain Area of Cangzhou Hebei 050061China

The Beijing-Tianjin-Hebei Plain(BTHP)is the political,economic and cultural center of China,where groundwater is the main source of water supply to support social and economic *** overdraft of the resources has caused a persistent decline of groundwater level and formed a huge cone of depression at a regional *** paper addresses current groundwater situation over the BTHP *** paper also delineates the groundwater flow field,using groundwater level data,in order to provide an effective method for the restoration of groundwater level and associated water resources *** on the analysis of multiple factors,such as groundwater level,soil salinization,ground subsidence,groundwater recharge and storage,urban underground space security,formation of fractures,and seawater intrusion,the threshold for groundwater level restoration is defined,and some measures for groundwater over-exploitation management are accordingly *** study shows that:(i)Since the 1980s to 2020,shallow groundwater level in the western part of the BTHP area has dropped by 25 m to 60m,while the cumulative decline of deep groundwater in the central and eastern regions is in the range of 40–80 m;(ii)The water table of the shallow groundwater within the depression zone over the Western Piedmont Plain should be controlled in the range of 15–30 m below ground level(mbgl),while the depth of groundwater level in large and medium-sized urban areas should be controlled within 20–30 *** groundwater level in the resource preservation area should be controlled within 10–15 mbgl,and the groundwater level in the area with identified soil salinization in the central and eastern plain should be controlled within 3–10 ***,for the deep groundwater in the central and eastern plainwater,the main focus of the resources management is to control the land *** water level in the severe land subsidence area should be controlled within 45–60 mbgl,and in the

关键词： Beijing-Tianjin-Hebei Plain Groundwater over-exploitation Groundwater level restoration threshold Groundwater reserve Over-exploitation control

Adhesion property of AlCrNbSiTi high-entropy alloy coating on zirconium:experimental and theoretical studies

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Nuclear Science and Techniques 2024年第8期35卷 79-91页

作者： Bao‑Liang Zhang Wen‑Guan Liu meng‑He Tu Can fang Yan Liu Yu‑Hui Wang Yong Hu Hui Wang China Institute of Atomic Energy Beijing 102413China Sino‑French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China

Experimental scratch tests and first-principles calculations were used to investigate the adhesion property of AlCrNbSiTi high-entropy alloy(HEA)coatings on zirconium *** HEA and Cr coatings were deposited on Zr alloy substrates using multi-arc ion plating technology,and scratch tests were subsequently conducted to estimate the adhesion property of the *** results indicated that Cr coatings had better adhesion strength than HEA coatings,and the HEA coatings showed *** special quasi-random structure approach was used to build HEA models,and Cr/Zr and HEA/Zr interface models were employed to investigate the cohesion between the coatings and Zr substrate using first-principles *** calculated interface energies showed that the cohesion between the Cr coating and the Zr substrate was stronger than that of the HEA coating with *** contrary to Al or Si in the HEA coating,Cr,Nb,and Ti atoms binded strongly with Zr *** on the calculated elastic constants,it was found that low Cr and high Al content decreased the mechanical performances of HEA ***,this study demonstrated the utilization of a combined approach involving first-principles calculations and experimental studies for future HEA coating development.

关键词： High-entropy alloy coating Cr coating Adhesion property Scratch test First-principles calculation

High resistance modulation by the electric field based on La_(0.9)Sr_(0.1)MnO_3/SrTiO_3/Si structure

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Science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1299-1301页

作者： YANG fang, HE meng, WEN Juan, JIN KuiJuan, LU HuiBin & YANG GuoZhen Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

A field-effect configuration based on La0.9Sr0.1MnO3/SrTiO3/Si structure is fabricated on Si substrate by laser molecular-beam epitaxy. The resistance modulation by electric field of the La0.9Sr0.1MnO3/SrTiO3/Si structure is investigated in detail. An evident resistance modulation effect is observed at 80 K. The channel resistance modulation by field effect reaches 1.4×107% and 2.6×106% when VDS are -2 and -6.5 V, respectively. The ON/OFF ratio of approximately 4000 is obtained. The present results are worthy of further investigations for potential applications of resistance modulation by electrostatic field in the heterostructures consisting of perovskite oxides and Si.

关键词： field effect perovskite oxide thin films resistance modulation

Effect of antimicrobial agents on the toll-like receptors and inflammatory cytokines in liver tissue of the alcohol-induced liver disease in rats with Vibrio vulnificus sepsis

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Chinese Medical Journal 2009年第16期122卷 1910-1916页

作者： LU Zhong-qiu LI meng-fang QIU Qiao-meng LIANG Huang ZHOU Tie-li HONG Guang-liang WU Bin Department of Emergency First Affiliated Hospital of Wenzhou Medical College. Wenzhou Zhejiang 325000 China

Background Septicemia and inflammation-mediated septic shock caused by Vibrio vulnificus （VV） is strongly associated with chronic liver disease. This study examined the effects of antimicrobial therapy on expression of hepatic toll-like receptors and inflammatory cytokines in rats with alcohol-induced liver disease complicated by VV sepsis. Methods Male Sprague-Dawley rats were assigned to the following treatment groups： normal control （N）, alcoholic liver disease control （A）, antimicrobial-treated alcoholic liver disease control （AA）, alcoholic liver disease with VV sepsis （AV）, and antimicrobial-treated alcoholic liver disease with VV sepsis （AVA）. Alcohol-induced liver disease was observed in all groups except N. Expression of mRNAs encoding hepatic toll-like receptors 2 and 4, myeloid differentiation protein-2, tumor necrosis factor-α （TNF-α）, interleukin （IL）-1β, IL-6 and IL-10 was determined by RT-PCR. Results mRNAs encoding toll-like receptors 2 and 4 and myeloid differentiation protein-2 were significantly up-regulated in group AV as compared to control groups at 2-24 hours of sepsis; peak expression occurred at 12 hours. These mRNAs were also up-regulated in group AVA but to lesser degrees than in group AV at comparable time post-infection, mRNAs encoding TNF-α, IL-1β and IL-6 were significantly elevated in group AV as a function of infection. In group AVA as compared to AV, expression of TNF-α and IL-1β mRNAs was lower at 12-24 hours post-infection and expression of IL-6 mRNA was lower at 24 hours post-infection. Compared with control groups, IL-10 mRNA expression in group AV was markedly higher at 12-24 hours of sepsis. Expression of IL-10 mRNA was lower in group AVA as compared to AV at 24 hours of sepsis. Conclusions Antimicrobial therapy reduces expression of toll-like receptors and cytokines in rats with alcohol-induced liver disease complicated by VV sepsis. Monitoring hepatic toll-like receptor and cytokine expression during antibiotic therapy may b

关键词： Vibrio vulnificus sepsis toll-like receptors inflammatory cytokines cefoperazone sodium levofloxacin