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Synthesis and characterization of a novel series of unsymmetrical porphyrins

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Chinese Chemical Letters 2007年第9期18卷 1021-1024页

作者： Lei wang Ya qing Feng Jin Qiang Xue Nai Kun Hu School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

A novel series of unsymmetrical porphyrins with aldehyde group at the terminal of the linkage which connected to meso-phenyl through acylamide bond have been synthesized and structurally characterized by IR, (1)H NMR,... 详细信息

关键词： Unsymmetrical porphyrin Synthesis Aldehyde group

Efficient Synthesis of Unsymmetrical Heteroaryl Ethers by a Transition Metal-Free C--O Cross-Coupling Reaction of Activated and Unactivated Heteroaryl Chlorides with Alcohols and Phenols

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Chinese Journal of Chemistry 2013年第6期31卷 764-772页

作者： Quan Liu Zhongxiang Lu Wenfei Ren Kaibo Shen Yu wang qing Xu College of Chemistry and Materials Engineering Wenzhou University Wenzhou Zhejiang 325035 China

By optimizing the reaction conditions via a careful screening of the bases and solvents, we developed an efficient transition metal-free method for C--O cross-coupling of activated and unactivated heteroaryl chlorides with primary and secondary alcohols and phenols, providing a simple, efficient, and practical method for synthesis of the useful unsymmetrical heteroaryl alkyl and heteroaryl aryl ethers.

关键词： alcohols C--O cross coupling heteroaryl ethers heteroaryl halides phenols transition metal-free

Accelerated glacier mass loss in the southeastern Tibetan Plateau since the 1970s

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Advances in Climate Change Research 2023年第3期14卷 372-386页

作者： Lan-Hua LUO Chang-qing KE Yu-Bin FAN Zi-Fei wang Jiangsu Provincial Key Laboratory of Geographic Information Science and Technology Key Laboratory for Land Satellite Remote Sensing Applications of Ministry of Natural ResourcesSchool of Geography and Ocean ScienceNanjing UniversityNanjing 210023China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210023China Collaborative Innovation Center of South China Sea Studies Nanjing 210023China

The southeastern Tibetan Plateau(SETP)is a region in High Mountain Asia with the most serious glacier mass ***,long-term and large regional-scale studies that estimate glacier mass balance in this area remain *** this study,we generated a KH-9 Digital Elevation Model(DEM)(covering 87.6%of the glacier area)for the 1970s from KH-9 Hexagon imagery and quantified geodetic glacier mass over the SETP from the 1970s to 2020 using KH-9 DEM,NASADEM and ICESat-2 ATL06 *** results show that the SETP was in a state of serious mass loss(at a rate of−0.35±0.03 m *** year)from the 1970s to 2020,and the rate of mass loss accelerated from−0.15±0.05 to−0.56±0.10 m *** year between the 1970s–2000 and 2000–*** the SETP,the glacier mass balance revealed a remarkable spatial *** maximum mean glacier mass loss rate was observed in the Hengduan *** exhibited the highest acceleration in the mass loss rate since the *** warming of air temperature and decreasing snowfall can partly explain the accelerated glacier mass loss in the *** study provides a new long-term glacier mass balance estimation covering almost the entire SETP that suggests the acceleration in glacier mass loss observed in the SETP since the 1970s is a regional tendency,which is crucial for understanding the relationship between glaciers and climate changes.

关键词： Glacier mass balance KH-9 hexagon imagery NASADEM ICESat-2 Southeastern Tibetan Plateau

Endogenous Hormone Concentration in Developing Tuberous Roots of Different Sweet Potato Genotypes

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Agricultural Sciences in China 2006年第12期5卷 919-927页

作者： wang qing-mei ZHANG Li-ming GUAN Yah-an wang Zhen-lin Agronomy Faculty Shandong Agricultural University/Shandong Provincial Laboratory of Crop Biology Taian 271018 P.R.China Crop Research Institute Shandong Academy of Agricultural Sciences Jinan 250100 P.R.China

A field trial was conducted to investigate the changes of endogenous hormone concentration （EHC） during formation and thickening of tuberous roots in sweet potato （Ipomoea batatas L.） of different genotypes： Xushu 18, Minamiyutaka, and L trifida-K123. The results of this study suggested that the concentrations of zeatin riboside （ZR）, dihydro-zeatin riboside （DHZR）, abscisic acid （ABA）, indole-3-acetic acid （IAA）, and isopentenyl-adenine （IPA） of Xushu 18 and Minamiyutaka were significantly higher than those of I. trifida-K123. Dry tuberous root yields were positively correlated with the concentration of ABA, ZR, and DHZR at 1 or 5% significant level, but were not obviously correlated with the concentrations of IAA, IPA, and GA4. The concentrations of ABA, ZR and DHZR played very important roles in the tuberous root formation and thickening in sweet potato. The concentrations of ZR, DHZR, ABA, and IAA in the upper or inner portion of tuberous roots were significantly higher than those toward the end of the root or its outer portion. Meanwhile, EHC of large-sized tuberous roots were significantly higher than those of medium- or small-sized tubers during the early thickening period. In the rapid thickening period of tuberous roots, EHC of medium-sized tubers were the highest, However, at the late-thickening period, EHC of small-sized tubers ranked the highest.

关键词： sweet potato tuber endogenous hormone concentration (EHC) formation thickening

First results of BDS positioning for LBS applications in the UK

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Satellite Navigation 2021年第1期2卷 111-129页

作者： Yan Xia Xiaolin Meng Yusong Yang shuguo Pan qing Zhao wang Gao School of Instrument Science and Engineering Southeast UniversityNanjing 210096China Key Laboratory of Micro-Inertial Instrument and Advanced Navigation Technology Ministry of EducationNanjing 210096China Nottingham Geospatial Institute The University of NottinghamNottingham NG72TUUK Global Geospatial Engineering Ltd./Sino-UK Geospatial Engineering Centre Radford Bridge RoadNottingham NG81NAUK State Key Laboratory of Media Convergence Production Technology and Systems Beijing 100031China School of Transportation Southeast UniversityNanjing 210096China.

The last satellite of BeiDou Navigation Satellite System with Global Coverage(BDS-3)constellation was successfully launched on June 23rd,2020,and the entire system began to provide Positioning,Navigation,and Timing(PNT)services *** evaluated the performance of location services using BDS with a smartphone that can track the Global Navigation Satellite System(GNSS)satellites in Nottingham,*** static and kinematic experiments were conducted in an open meadow and a lakeside route covered by trees,*** results show that BDS has good visibility,and its overall signal carrier-to-noise density ratio(C/N0)is comparable to that of Global Positioning System(GPS).The average C/N0 of BDS-3 satellites with elevation angles above 45°on B1 band is the highest among all systems,reaching 40.0 dB·*** noise level of the BDS pseudorange measurements is within 0.5 m,and it has a good consistency among *** the static experiment,the standard deviations of BDS position-ing in the east,north and up directions are 1.09,1.16,and 3.02 m,respectively,and the R95 value of the horizontal position is 2.88 *** harsh environments,the number of BDS satellites tracked by the smartphone is susceptible to environmental *** bias Root Mean Squares(RMS)in the three directions of the whole kinematic positioning are 6.83,6.68,11.67 m,in which the positioning bias RMS values in a semi-open environment are only 2.81,1.11,3.29 ***,the inclusion of BDS in multiple GNSS systems can significantly improve the positioning *** study intends to provide a reference for the further improvements of BDS global PNT services,particularly for Location-Based Services(LBS).

关键词： BDS Android smartphone Observation quality LBS UK

Analyses of temperature and humidity profiles and heat balance of the surface boundary-layer in the hinterland of the Taklimakan Desert

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Chinese Science Bulletin 2008年第S2期53卷 22-30页

作者： WEI WenShou wang MinZhong HE qing LEI JiaQiang ALI Mamtimin Institute of Desert Meteorology China Meteorological AdministrationUrumqi 830002China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

The daily variation regularities of micro-meteorological features, such as the surface layer temperature and humidity profiles of the inner desert in summer, the temperature of sand bed, the radiation of the earth's surface and the heat balance, were analyzed by combination method and logarithm regression according to the data obtained from the Atmospheric Environmental Observation Station of Taklimakan Desert in July―August of 2006 and 2007. It has been shown that temperature inversion occurred near the surface layer at night in summer, the temperature increased with the height within a certain altitude range, and the reverse was true during the daytime. The ground surface radiation balance of the Taklimakan Desert was mainly positive; other radiation components (the global radiation, the reflective radiation, the ground upward long wave radiation and the net radiation) exhibited daily variation char- acteristics evidently and showed normal diurnal cycle, except for the downward atmospheric long-wave radiation. The heat exchange of the surface layer of the desert was dominated by turbulence sensible heat, and only a small portion of heat was transferred to the atmospheric surface layer in the form of latent heat. The surface sensible heat and latent heat changed with the increase and decrease of sun elevation angle, with maximum of the latent heat appearing in wee hours and the peak value of the sensible heat appearing at noon. Observation and analysis showed that heating effect of the underlying surface of the desert was great on the aerosphere; the surface was a high heat source during the day and became a weak cold source at night.

关键词： Taklimakan Desert temperature profile humidity profile radiation balance heat balance

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沈阳现代化都市圈水供给服务供需平衡研究

水生态学杂志 2024年第4期45卷 48-55页

作者：程雨露魏建兵陆庆轩郑泓王阳程全国沈阳大学区域污染环境生态修复教育部重点实验室辽宁沈阳110044 沈阳大学生命科学与工程学院辽宁沈阳110044

以沈阳现代化都市圈为研究区,从地级市尺度上综合自然水文过程和居民生产、生活消费需求,揭示区域水供给服务供需平衡关系,为区域水资源优化管理提供依据。基于GIS平台,采用2000、2010和2020年土地利用数据,耦合InVest模型产水量模块、... 详细信息

以沈阳现代化都市圈为研究区,从地级市尺度上综合自然水文过程和居民生产、生活消费需求,揭示区域水供给服务供需平衡关系,为区域水资源优化管理提供依据。基于GIS平台,采用2000、2010和2020年土地利用数据,耦合InVest模型产水量模块、水需求服务模型、水资源安全指数等多种方法,以空间可视化的方式模拟研究水供给服务格局。研究结果表明:2000-2020年沈阳现代化都市圈水供给量和水需求量均呈现先增多后减少的趋势,供需平衡状况差距较大;2000年沈阳市、鞍山市、辽阳市、铁岭市、阜新市的水资源安全指数以及2010年、2020年沈阳市、辽阳市水资源安全指数均低于0.5;研究区水供给服务的供给与需求在空间分布上呈现显著的不匹配特征,区域东部铁岭市、抚顺市、本溪市为主要供给区,中部沈阳市、辽阳市需大于供,水资源供需矛盾突出。研究框架思路与研究结果能够为都市圈尺度水资源供需矛盾的协调提供一定的决策依据。

关键词：水供给服务 InVest模型水供需平衡水资源安全沈阳现代化都市圈

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Remarkable difference of phospholipid molecular chirality in regulating PrP aggregation and cell responses

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中国化学快报：英文版 2023年第2期34卷 236-243页

作者： Cunli wang Xue wang Dongdong wang Shengxu Qian Fusheng Zhang Mingyang Li Minmin Li Wenqi Lu Bo Liu Guangyan qing School of Biomedical Engineering Dalian University of TechnologyDalian 116024China CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China College of Chemistry and Chemical Engineering Wuhan Textile UniversityWuhan 430200China

Prion diseases are fatal neurodegenerative diseases that can cause severe *** misfolding and accumulation of the prion peptide (PrP)_(106–126) is crucial,and this process is closely relevant to biological ***,how PrP_(106–126)aggregation is affected by the molecular chirality of phospholipid membrane is ***,in this study,a pair of L-and D-aspartic acid (Asp)-modified 1,2-dipalmitoyl-sn–glycero-3-phosphoethanolamine (DPPE) were synthesized to construct chiral *** discover that L-Asp-DPPE liposomes strongly inhibit the oligomerization and amyloidogenesis of PrP_(106–126),whether acting on monomers or oligomers,which rescues cytotoxicity induced by PrP_(106–126).By comparison,D-Asp-DPPE liposomes inhibit peptide oligomerization only at a high concentration and cannot prevent amyloidogenesis when acting on oligomers,which lead to pronounced *** experiment,dynamic change of intracellular Ca^(2+)(_(i)Ca^(2+)) and Ca^(2+)release from endoplasmic reticulum(ER),reactive oxygen species (ROS) production,adsorption dynamics and affinity tests,and fluorescent imaging clearly disclose that molecular chirality of the liposomes dominates conformational transition of PrP_(106–126)from random coil to β-sheet,binding and adsorption of the monomers and oligomers,and subsequent fibrillation process,resulting in distinct inhibition effect in Ca^(2+)overload and release,ROS production and cell *** work is the first to report that interfacial molecular chirality is a potentially crucial influence on the fibrillation process of PrP_(106–126) and its cell responses,whereas the convergence of chiral amino acids and liposomes can be considered potential inhibitors in prion diseases.

关键词： Prion disease Liposome Chirality Interface Cytosolic Ca^(2+)

Relationship between thermal anomalies in Tibetan Plateau and summer dust storm frequency over Tarim Basin,China

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Journal of Arid Land 2013年第1期5卷 25-31页

作者： Yong ZHAO HongJun LI AnNing HUANG qing HE Wen HUO MinZhong wang Institute of Desert Meteorology China Meteorological Administration Urumqi 830002 China School of Atmospheric Sciences Nanjing University Nanjing 210093 China

The dust storm is the most important and frequent meteorological disaster over Tarim Basin, which causes huge damages on local social economics. How to predict the springtime and summertime dust storm oc- currence has become a hot issue for meteorologists. This paper employed the data of dust storm frequency and 10-m wind velocity at 35 stations over Tarim Basin and the reanalysis data from the National Center for Environ- mental Prediction and the National Center for Atmospheric Research （NCEP/NCAR） during 1961-2007 to study the relationship between dust storm frequency （DSF） in summer over Tarim Basin and the thermal anomalies in Tibetan Plateau in May by using the statistical methods, such as Empirical Orthogonal Function （EOF）, correlation and binomial moving average. The results show when negative anomalies in Tibetan Plateau and positive anomalies in its southern region are present along 30~N （the second mode of surface temperature anomalies by EOF decomposition） in May, the time coefficient （PC2） plays an important role in summer DSF variation and has a close relation with the summer DSF at both inter-annual and decadal time scales. When negative anomalies in Tibetan Plateau and positive anomalies are present in its southern region （PC2 in positive phase）, there is an anomalous anticyclone in North China, which weakens the northwest wind and is not beneficial for cold air moving from high latitude to the Tarim Basin, and the circulation pattern is hard to result in dust storm weather. Furthermore, the sea level pressure （SLP） increased over Tarim Basin and the direction of SLP gradient reversed, which resulted in the 10-m wind velocity slowing down, so the DSF decreased. From above all, it can be conclude that the thermal anomalies in Tibetan Plateau in May has important effects on the summertime dust storm frequency over Tarim Basin and the PC2 can be used as a prediction factor for the summertime dust storm occurrence.

关键词： dust storm frequency thermal anomalies Tarim Basin Tibetan Plateau