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Journal of Environmental Sciences 2014年第8期26卷 1763-1768页

作者： Huirong Lin Chengsong Ye Lu Lv clark renjun zheng Shenghua Zhang Lei zheng Yidong Zhao Xin Yu Institute of Urban Environment Chinese Academy of Science Beijing No.4 High School Institute of High Energy Physics Chinese Academy of ScienceBeijing Synchrotron Radiation Facility

A combined approach of physicochemical extraction and sulfur K-edge X-ray absorption near-edge structure（XANES） spectroscopy was applied to characterize the extracellular polymeric substances（EPS） of typical bacterial biofilms in this study. Physicochemical analysis showed variation of the contents of DNA,polysaccharide and protein in different fractions of EPS in different mediums. The sulfur K-edge XANES analysis yielded a variety of *** fitting of the XANES spectra utilizing a large set of model compounds showed that there was more reduced sulfur in both LB-EPS（loosely bound EPS） and TB-EPS（tightly bound EPS） of all the biofilms in LB medium than in R2 A medium. More oxidized sulfur was identified in LB-EPS than that in TB-EPS,suggesting different niches and physiological heterogeneity in the biofilms. Our results suggested that the sulfur K-edge XANES can be a useful tool to analyze the sulfur speciation in EPS of biofilms.

关键词： Biofilms Characterization EPS Sulfur XANES

Highly efficient NHC-iridium-catalyzedβ-methylation of alcohols with methanol at low catalyst loadings

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Science China Chemistry 2021年第8期64卷 1361-1366页

作者： Zeye Lu Qingshu zheng Guangkuo Zeng Yunyan Kuang James H.clark Tao Tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou450001China Green Chemistry Centre of Excellence University of YorkYorkYO 105DDUK

The methylation of alcohols is of great importance since a broad number of bioactive and pharmaceutical alcohols contain methyl ***,a highly efficientβ-methylation of primary and secondary alcohols with methanol has been achieved by using bis-N-heterocyclic carbene iridium(bis-NHC-Ir)*** substrate scope and up to quantitative yields were achieved at low catalyst loadings with only hydrogen and water as *** protocol was readily extended to theβ-alkylation of alcohols with several primary *** experiments,along with DFT calculations and crystallographic studies,revealed that the ligand effect is critical to their excellent catalytic performance,shedding light on more challenging Guerbet reactions with simple alcohols.

关键词： hydrogen-borrowing ligand effect iridium N-heterocyclic carbene methylation

2000—2018年长株潭城市群城市扩张及其热岛响应

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自然资源遥感 2024年第1期36卷 162-168页

作者：姚灵筠王力牛铮尹子琪付雨文中国科学院空天信息创新研究院遥感科学国家重点实验室北京100094 中国科学院大学北京100049

城市热岛效应同城市居民福祉息息相关,特别是近20 a我国的中西部城市在快速城市化的背景下,城市扩张进程进一步加快,城市热岛效应的影响也随之不断增加。为探究城市及城市群扩张与城市热岛效应变化的关系,以长株潭城市群为研究区域,利用... 详细信息

城市热岛效应同城市居民福祉息息相关,特别是近20 a我国的中西部城市在快速城市化的背景下,城市扩张进程进一步加快,城市热岛效应的影响也随之不断增加。为探究城市及城市群扩张与城市热岛效应变化的关系,以长株潭城市群为研究区域,利用Boyce-clark形状指数分析城市扩张进程及空间形态变化。首先,利用基于Google Earth Engine(GEE)平台的实用单通道算法进行温度反演;然后,使用均值-标准差法划分温度等级区并定义和提取城市热岛范围;最后,提取城市重心和热岛重心,采用重心迁移方法分析城市扩张与热岛效应之间的变化趋势。结果表明城市热岛变化与城市群城市扩张趋势一致,研究结论如下:①2015年后长株潭城市群进入高速发展关键时期;②城市扩张是热岛面积增加的主要原因;③城市热岛重心与城市重心迁移趋势基本一致,城市热岛范围增加的方向也同城市扩张方向基本一致。

关键词：城市热岛效应城市空间形态地表温度 Boyce-clark形状指数重心迁移

FTIR Analysis of Protein Secondary Structure in Cheddar Cheese during Ripening

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光谱学与光谱分析 2011年第7期31卷 1786-1789页

作者： WANG Fang LIU Ai-ping REN Fa-zheng ZHANG Xiao-ying Stephanie clark ZHANG Lu-da GUO Hui-yuan College of Food Science ＆ Nutritional Engineering China Agricultural University Key Laboratory of Functional Dairy Ministry of Education Beijing 100083 China Beijing Higher Institution Engineering Research Center of Animal Product Beijing 100083 China Department of Food Science and Human Nutrition Iowa State University Iowa 50011 USA College of Science China Agricultural University Beijing 100094 China

Proteolysis is one of the most important biochemical reactions during cheese *** on the secondary structure of proteins during ripening would be helpful for characterizing protein changes for assessing cheese *** transform infrared spectroscopy(FTIR),with self-deconvolution,second derivative analysis and band curve-fitting,was used to characterize the secondary structure of proteins in Cheddar cheese during *** spectra of the amide I region showed great similarity,while the relative contents of the secondary structures underwent a series of *** ripening progressed,the α-helix content decreased and the β-sheet content *** structural shift was attributed to the strengthening of hydrogen bonds that resulted from hydrolysis of *** summary,FTIR could provide the basis for rapid characterization of cheese that is undergoing ripening.

关键词： FTIR Cheddar cheese Ripening Protein secondary structure

Relationships between interspecific differences in the mass of internal organs,biochemical markers of metabolic activity,and the thermogenic properties of three smallpasserines

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Chinese Birds 2016年第2期7卷 116-124页

作者： Minlan Bai Xujian Wu Kejing Cai Weihong zheng Jinsong Liu School of Life and Environmental Sciences Wenzhou University Zhejiang Provincial Key Lab for Subtropical Water Environment and Marine Biological Resources Protection

Background:The capacity for thermogenesis is considered part of an animal's adaptive strategy for survival,and basal metabolic rate(BMR) is one of the fundamental physiological standards for assessing the energy cost of thermoregulation in *** has been shown to be a highly flexible phenotypic trait both between,and within,species,but the metabolic mechanisms involved in the regulation of BMR,which range from variation in organ mass to biochemical adjustments,remain *** this study,we investigated the relationship between organ mass,biochemical markers of metabolic tissue activity,and thermogenesis,in three species of small passerines:wild Bramblings(Fringilla montifringilla),Little Buntings(Emberiza pusilla) and Eurasian Tree Sparrows(Passer montanus),caught in Wenzhou,southeastern ***:Oxygen consumption was measured using an open-circuit respirometry *** state-4 respiration and cytochrome c oxidase(COX) activity in liver and pectoral muscle were measured with a clark ***:Our results show that Eurasian Tree Sparrows had significantly higher BMR,digestive organ mass,mitochondrial state-4 respiration capacity and COX activity in liver and muscle,than Bramblings and Little ***,interspecific differences in BMR were strongly correlated with those indigestive tract mass,state-4 respiration and COX ***:Our findings suggest that the digestive organ mass,state-4 respiration and COX activity play an important role in determining interspecific differences in BMR.

关键词： Basal metabolic rate(BMR) Cytochrome c oxidase(COX) State-4 respiration Fringilla montifringilla Emberiza pusilla Passer montanus

Food restriction decreases BMR,body and organ mass,and cellular energetics,in the Chinese Bulbul(Pycnonotus sinensis)

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Avian Research 2018年第4期9卷 370-380页

作者： Yiying Zhang Ke Yang Peipei Yang Yingshi Su Weihong zheng Jinsong Liu School of Life and Environmental Sciences Wenzhou UniversityWenzhou’s Chashan University TownWenzhou 325035China Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection Wenzhou 325035China

Background: Food is an important environmental factor that affects animals' energy metabolism and food shortage has significant effects on animals' behavior, physiology and biochemistry. However, to date few studies have focused on the thermogenesis and its effects on the body condition of birds. In this study, we examined the effects of food restriction on the body mass, basal metabolic rate(BMR) and body composition, and several physiological, biochemical and molecular markers potentially related to thermogenesis, in the Chinese Bulbul(Pycnonotus sinensis).Methods: Birds in the control group were provided with food ad libitum whereas those in the food restriction group were provided with one-half of the usual quantity of food for 12 days. Oxygen consumption was measured using an open-circuit respirometry system. Mitochondrial state 4 respiration and cytochrome c oxidase(COX) activity in the liver and pectoral muscle were measured with a clark electrode. Avian uncoupling protein(avUCP) mRNA expression was determined in pectorals muscle with quantitative Real-time ***:Chinese Bulbuls in food restriction group decreased in body mass,BMR and internal organ(heart,kidneys,small intestine and total digestive tract)mass compared with the control group over the 12-day period of food *** in the food restriction group also had lower levels of state-4 respiration,COX activity in the liver and muscle,and mitochondrial avUCP gene expression in muscle compared to the control *** was positively correlated with body mass,state 4 respiration in the liver and COX activity in the ***:Our data indicate that Chinese Bulbuls not only sustain food shortage through simple passive mechanisms,such as reducing body and organ mass and energy expenditure,but also by reducing energetic metabolism in the liver and muscle.

关键词： Avian uncoupling protein Basal metabolic rate Cytochrome c oxidase Food restriction Pycnonotus sinensis State-4 respiration

Seasonal phenotypic flexibility in body mass,basal thermogenesis,and tissue oxidative capacity in the male Silky Starling(Sturnus sericeus)

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Avian Research 2017年第4期8卷 243-254页

作者： Min Li Yingqiao Sun Hongzhen Mao Jinhua Xu Weihong zheng Jinsong Liu School of Life and Environmental Sciences Wenzhou UniversityWenzhou 325035China Zhejiang Provincial Key Lab for Subtropical Water Environment and Marine Biological Resources Protection Wenzhou 325035China

Background: Acclimatization to winter conditions is an essential prerequisite for the survival of small birds in the northern temperate *** in photoperiod,ambient temperature and food availability trigger seasonal physiological and behavioral acclimatization in many *** trends in metabolic parameters are well known in avian populations from temperate environments;however,the physiological and biochemical mechanisms underlying these trends are incompletely *** this study,we used an integrative approach to measure variation in the thermogenic properties of the male Silky Starling(Sturnus sericeus) at different levels or organization,from the whole organism to the *** measured body mass(Mb),basal metabolic rate(BMR),energy budget,the mass of selected internal organs,state 4 respiration and cytochrome c oxidase(COX) activity in the heart,liver and ***: Oxygen consumption was measured using an open-circuit respirometry *** energy intake of the birds were then determined using an oxygen bomb *** state 4 respiration and COX activity in heart,liver and pectoral muscle were measured with a clark ***: The results suggest that acclimatization to winter conditions caused significant change in each of the measured variables,specifically,increases in Mb,organ mass,BMR,energy intake and cellular enzyme ***,BMR was positively correlated with body mass,energy intake,the mass of selected internal organs,state 4 respiration in the heart,liver and muscle,and COX activity in the heart and ***: These results suggest that the male Silky Starling's enhanced basal thermogenesis under winter conditions is achieved by making a suite of adjustments from the whole organism to the biochemical level,and provide further evidence to support the notion that small birds have high phenotypic plasticity with respect to seasonal changes.

关键词： Basal metabolic rate(BMR) Cytochrome c oxidase(COX) Organ mass Seasonal variation Sturnus sericeus State 4 respiration

The role of temperature as a driver of metabolic flexibility in the Red-billed Leiothrix(Leiothrix lutea)

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Avian Research 2019年第4期10卷 485-496页

作者： Danqi Cui Na Wang Jingru Ge Jiaying Xu Weihong zheng Jinsong Liu School of Life and Environmental Sciences Wenzhou UniversityWenzhou 325035China Zhejiang Provincial Key Lab for Subtropical Water Environment and Marine Biological Resources Protection Wenzhou 325035China

Background:The thermoregulatory ability of animals is strongly influenced by the temperature of their *** to cold requires a range of physiological and morphological *** this study,we tested the hypothesis that a small passerine,the Red-billed Leiothrix(Leiothrix lutea),can maintain homeothermy in cold conditions by adjusting the physiology and biochemistry of its tissue and organs and return to its former physiological and biochemical state when moved to a warm ***:Phenotypic variation in thermogenic activity of the Red-billed Leiothrixs(Leiothrix lutea)was investigated under warm(35℃),normal(25℃)or cold(15℃)ambient temperature *** consumption was measured using an open-circuit respirometry *** state-4 respiration and cytochrome-c oxidase(COX)activity in liver,kidney heart and pectoral muscle were measured with a clark ***:Birds acclimated to an ambient temperature of 15℃ for 4 weeks significantly increased their basal metabolic rate(BMR)compared to a control group kept at 25℃.Birds acclimated to 35℃ decreased their BMR,gross energy intake(GEI)and digestible energy intake(DEI).Furthermore,birds acclimated to 15℃ increased state-4 respiration in their pectoral muscles and cytochrome-c oxidase(COX)activity in their liver and pectoral muscle,compared to the 25℃ control *** acclimated to 35℃ also displayed lower state-4 respiration and COX activity in the liver,heart and pectoral muscles,compared to those kept at 25℃.There was a positive correlation between BMR and state-4 respiration,and between BMR and COX activity,in all of the above organs except the liver and ***:Our study illustrates that the morphological,physiological,and enzymatic changes are associated with temperature acclimation in the Red-billed Leiothrix,and supports the notion that the primary means by which small birds meet the energetic challenges of cold conditions is through metabolic adj

关键词： Basal metabolic rate Cold acclimation Cytochrome C oxidase Leiothrix lutea State-4 respiration

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壳牌对未来车用能源多元化发展趋势的思考

汽车安全与节能学报 2020年第1期11卷 17-35页

作者：贾恬郑彬 Warnecke W Kolbeck A Aradi A Kofod M clark R Wilbrand K 壳牌(上海)技术有限公司上海201210 Shell Global Solutions(Germany)GmbH Hamburg 21107Germany Shell Global Solutions US Inc Houston 77082-3101USA Shell Global Solutions(UK)Ltd London SE17NAUK

面对能源短缺和环境污染的双重挑战,交通领域的转型升级不可避免。本文结合未来车用动力系统的发展趋势,对交通运输领域中应用的多种先进动力系统、清洁能源及替代燃料进行综述和评价,包括目前主要使用的传统液态化石燃料即汽、柴油及... 详细信息

面对能源短缺和环境污染的双重挑战,交通领域的转型升级不可避免。本文结合未来车用动力系统的发展趋势,对交通运输领域中应用的多种先进动力系统、清洁能源及替代燃料进行综述和评价,包括目前主要使用的传统液态化石燃料即汽、柴油及先进内燃机技术,清洁替代燃料(如生物燃料、天然气合成油(GTL)燃料、电转液(PTL)燃料、液化天然气(LNG)等),以及电气化动力系统(包括混合动力、纯电动和燃料电池)等,并着重讨论液体燃料。壳牌认为没有一种单一的解决方案可以解决复杂的能源问题,未来交通能源结构将呈现多种能源并存的特点,并分别适用于不同的场景。该文还介绍了壳牌近期基于不同政治、经济和社会发展程度提出的3种远景(壳牌“高山”、“海洋”和“天空”远景),提出壳牌对未来车用能源领域转型脱碳发展情景的思考。

关键词：清洁替代燃料内燃机技术生物燃料天然气合成油(GTL) 电转液(PTL)燃料液化天然气(LNG) 电气化动力总成远景预测

3D RNA nanocage for encapsulation and shielding of hydrophobic biomolecules to improve the in vivo biodistribution

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Nano Research 2020年第12期13卷 3241-3247页

作者： Congcong Xu Kaiming Zhang Hongran Yin Zhefeng Li Alexey Krasnoslobodtsev Zhen zheng Zhouxiang Ji Sijin Guo Shanshan Li Wah Chiu Peixuan Guo Center for RNA Nanobiotechnology and Nanomedicine College of PharmacyDivision of Pharmaceutics and Pharmaceutical ChemistryCollege of MedicineDorothy M.Davis Heart and Lung Research InstituteJames Comprehensive Cancer CenterThe Ohio State UniversityColumbusOH43210USA Department of Bioengineering James H.Clark CenterStanford UniversityStanfordCA94305USA Department of Physics University of Nebraska at OmahaOmahaNE68182USA Nanoimaging Core Facility Office of Vice-Chancellor for ResearchUniversity of Nebraska Medical CenterOmahaNE68198USA SLAC National Accelerator Laboratory Stanford UniversityMenlo ParkCA94025USA

Ribonucleic acid(RNA)nanotechnology platforms have the potential of harboring therapeutics for in vivo delivery in disease ***,the nonspecific interaction between the harbored hydrophobic drugs and cells or other components before reaching the diseased site has been an obstacle in drug *** we report an encapsulation strategy to prevent such nonspecific hydrophobic interactions in vitro and in vivo based on a self-assembled three-dimensional(3D)RNA *** placing an RNA three-way junction(3WJ)in the cavity of the nanocage,the conjugated hydrophobic molecules were specifically positioned within the nanocage,preventing their exposure to the biological *** assembly of the nanocages was characterized by native polyacrylamide gel electrophoresis(PAGE),atomic force microscopy(AFM),and cryogenic electron microscopy(cryo-EM)*** stealth effect of the nanocage for hydrophobic molecules in vitro was evaluated by gel electrophoresis,flow cytometry,and confocal *** in vivo sheathing effect of the nanocage for hydrophobic molecules was assessed by biodistribution profiling in *** RNA nanocages with hydrophobic biomolecules underwent faster clearance in liver and spleen in comparison to their ***,this encapsulation strategy holds promise for in vivo delivery of hydrophobic drugs for disease treatment.

关键词： ribonucleic acid(RNA)nanocage three-way junction(3WJ) encapsulation hydrophobic biomolecule RNA nanotechnology