维普中文期刊产品整合服务
64篇 您的检索式:作者名="Jingyun Yang"
    题名 作者 年代 出处 被引量
1Terrestrial carbon sinks in China and around the world and their contribution to carbon neutrality显示文摘Enhancing the terrestrial ecosystem carbon sink(referred to as terrestrial C sink) is an important way to slow down the continuous increase in atmospheric carbon dioxide(CO_(2)) concentration and to achieve carbon neutrality target.To better understand the characteristics of terrestrial C sinks and their contribution to carbon neutrality,this review summarizes major progress in terrestrial C budget researches during the past decades,clarifies spatial patterns and drivers of terrestrial C sources and sinks in China and around the world,and examines the role of terrestrial C sinks in achieving carbon neutrality target.According to recent studies,the global terrestrial C sink has been increasing from a source of (-0.2±0.9) Pg C yr^(-1)(1 Pg=1015g)in the 1960s to a sink of (1.9±1.1) Pg C yr^(-1) in the 2010s.By synthesizing the published data,we estimate terrestrial C sink of 0.20–0.25 Pg C yr^(-1) in China during the past decades,and predict it to be 0.15–0.52 Pg C yr^(-1) by 2060.The terrestrial C sinks are mainly located in the mid-and high latitudes of the Northern Hemisphere,while tropical regions act as a weak C sink or source.The C balance differs much among ecosystem types:forest is the major C sink;shrubland,wetland and farmland soil act as C sinks;and whether the grassland functions as C sink or source remains unclear.Desert might be a C sink,but the magnitude and the associated mechanisms are still controversial.Elevated atmospheric CO_(2) concentration,nitrogen deposition,climate change,and land cover change are the main drivers of terrestrial C sinks,while other factors such as fires and aerosols would also affect ecosystem C balance.The driving factors of terrestrial C sink differ among regions.Elevated CO_(2) concentration and climate change are major drivers of the C sinks in North America and Europe,while afforestation and ecological restoration are additionally important forcing factors of terrestrial C sinks in China.For future studies,we recommend the necessity for intensive and long-term ecosystem C monitoring over broad geographic scale to improve terrestrial biosphere models for accurately evaluating terrestrial C budget and its dynamics under various climate change and policy scenarios.Yuanhe Yang Yue Shi Wenjuan Sun Jinfeng Chang Jianxiao Zhu Leiyi Chen Xin Wang Yanpei Guo Hongtu Zhang Lingfei Yu Shuqing Zhao Kang Xu Jiangling Zhu Haihua Shen Yuanyuan Wang Yunfeng Peng Xia Zhao Xiangping Wang Huifeng Hu Shiping Chen Mei Huang Xuefa Wen Shaopeng Wang Biao Zhu Shuli Niu Zhiyao Tang Lingli Liu Jingyun Fang 2022Science China(Life Sciences)2022,65,5:32
2Variations of root and heterotrophic respiration along environmental gradients in China’s forests显示文摘Aims Root and heterotrophic respiration may respond differently to environmental variability,but little evidence is available from largescale observations.Here we aimed to examine variations of root and heterotrophic respiration across broad geographic,climatic,soil and biotic gradients.Methods We conducted a synthesis of 59 field measurements on root and heterotrophic respiration across China’s forests.Important Findings Root and heterotrophic respiration varied differently with forest types,of which evergreen broadleaf forest was significantly different from those in other forest types on heterotrophic respiration but without statistically significant differences on root respiration.The results also indicated that root and heterotrophic respiration exhibited similar trends along gradients of precipitation,soil organic carbon and satellite-indicated vegetation growth.However,they exhibited different relationships with temperature:root respiration exhibited bimodal patterns along the temperature gradient,while heterotrophic respiration increased monotonically with temperature.Moreover,they showed different relationships with MOD17 GPP,with increasing trend observed for root respiration whereas insignificant change for heterotrophic respiration.In addition,root and heterotrophic respiration exhibited different changes along the age sequence,with insignificant change for root respiration and decreasing trend for heterotrophic respiration.Overall,these results suggest that root and heterotrophic respiration may respond differently to environmental variability.Our findings could advance our understanding on the different environmental controls of root and heterotrophic respiration and also improve our ability to predict soil CO_(2) flux under a changing environment.Pin Li Yuanhe Yang Jingyun Fang 2013Journal of Plant Ecology2013,6,5:11
3Major advances in studies of the physical geography and living environment of China during the past 70 years and future prospects显示文摘The natural environment provides material essentials for human survival and development. The characteristics,processes, regional differentiation and forcing mechanisms of the elements of the natural environment(e.g. geomorphology,climate, hydrology, soil, etc.) are the main objects of research in physical geography. China has a complex natural environment and huge regional differentiation and therefore it provides outstanding reserach opportunities in physical geography. This review summarizes the most important developments and the main contributions of research in the physical geography and human living environment in China during the past 70 years. The major topics addressed are the uplift of the Tibetan Plateau and the evolution of its cryosphere, the development of fluvial systems, the acidification of the vast arid region of the Asian interior, variations in the monsoon and westerly climate systems on multiple timescales, the development of lakes and wetlands, the watershed system model, soil erosion, past human-environment interactions, biogeography, and physical geographic zonality. After briefly introducing international research developments, we review the history of research in physical geography in China, focusing on the major achievements and major academic debates, and finally we summarize the status of current research and the future prospects. We propose that in the context of the national demand for the construction of an ecological civilization, we should make full use of the research findings of physical geography, and determine the patterns and mechanisms of natural environmental processes in order to continue to promote the continued contribution of physical geography to national development strategies, and to further contribute to the theory of physical geography from a global perspective.Fahu CHEN Bojie FU Jun XIA Duo WU Shaohong WU Yili ZHANG Hang SUN Yu LIU Xiaomin FANG Boqiang QIN Xin LI Tingjun ZHANG Baoyuan LIU Zhibao DONG Shugui HOU Lide TIAN Baiqing XU Guanghui DONG Jingyun ZHENG Wei YANG Xin WANG Zaijun LI Fei Wang Zhenbo HU Jie WANG Jianbao LIU Jianhui CHEN Wei HUANG Juzhi HOU Qiufang CAI Hao LONG Ming JIANG Yaxian HU Xiaoming FENG Xingguo MO Xiaoyan YANG Dongju ZHANG Xiuhong WANG Yunhe YIN Xiaochen LIU 2019Science China Earth Sciences2019,62,11:11
4The binding of a monoclonal antibody to the apical region of SCARB2 blocks EV71 infection显示文摘(EV71 ) Entero 病毒 71 引起手,脚,和嘴疾病(HFMD ) 并且偶尔导致严重神经病学的复杂并发症甚至死亡。(SCARB2 ) Scavenger 受体班 B 成员 2 是为 EV71 的功能的受体,调停病毒的附件,成为主观,和 uncoating。然而, SCARB2 上的 EV71 的准确有约束力的地点是未知的。在这研究,我们产生了绑在人然而并非老鼠 SCARB2 的 monoclonal 抗体(mAb ) 。它被称为 JL2,并且它能有效地禁止目标房间的 EV71 感染。用人和老鼠 SCARB2 的一套怪物,我们鉴别包含人的 SCARB2 的残余 77-113 的区域显著地作出贡献到 JL2 绑定。SCARB2-JL2 建筑群的结构表明 JL2 绑在包含 -helices 的 SCARB2 的顶端的区域 2, 5,和 14。我们的结果在 SCARB2 和 EV71 入口的分子的机制上为 EV71 提供新卓见进潜在的有约束力的地点。Xuyuan Zhang Pan Yang Nan Wang Jialong Zhang Jingyun Li Hao Guo Xiangyun Yin Zihe Rao Xiangxi wang Liguo Zhang 2017Protein & Cell2017,8,8:10
5A facile surfactant-free synthesis of Rh flower-like nanostructures constructed from ultrathin nanosheets and their enhanced catalytic properties显示文摘Rh 是广泛地在许多器官的反应被使用的重要催化剂。在最近的年里,许多努力集中了于由与控制尺寸和形态学制作催化剂 nanoparticles 改进它的催化效率。然而,也把有机化合物用作反应媒介或盖住代理人的经常采用的合成线路经常在催化剂表面上导致剩余分子,它急速地接着减少催化表演。此处,我们报导甲醛经由 Rh (acac )3 的热水的减小获得的新奇 Rh 象花的结构的灵巧的、水的、没有表面活化剂的合成。唯一的 Rh nanoflowers 从 ultrathin nanosheets 被构造,其基础表面包括了 { 111 } 有 ~ 的平均厚度的方面 1.1 nm。特定的表面区域由公司脱衣测量了 79.3 是 m 2 钟声到 134.4 食火鸟的浸透的磁化 ???? 愠汬祯湩吗??Yaqi Jiang Jingyun Su Yanan Yang Yanyan Jia Qiaoli Chen Zhaoxiong Xie Lansun Zheng 2016Nano Research2016,9,3:7
6Spontaneous apoptosis of cells in therapeutic stem cell preparation exert immunomodulatory effects through release of phosphatidylserine显示文摘Mesenchymal stem cell(MSC)-mediated immunomodulation has been harnessed for the treatment of human diseases,but its underlying mechanism has not been fully understood.Dead cells,including apoptotic cells have immunomodulatory properties.It has been repeatedly reported that the proportion of nonviable MSCs in a MSC therapeutic preparation varied from 5-50%in the ongoing clinical trials.It is conceivable that the nonviable cells in a MSC therapeutic preparation may play a role in the therapeutic effects of MSCs.We found that the MSC therapeutic preparation in the present study had about 5%dead MSCs(DMSCs),characterized by apoptotic cells.Namely,1×10^(6) MSCs in the preparation contained about 5×10^(4) DMSCs.We found that the treatment with even 5×10^(4) DMSCs alone had the equal therapeutic effects as with 1×10^(6) MSCs.This protective effect of the dead MSCs alone was confirmed in four mouse models,including concanavalin A(ConA)-and carbon tetrachloride(CCI4)-induced acute liver injury,LPS-induced lung injury and spinal cord injury.We also found that the infused MSCs died by apoptosis in vivo.Furthermore,the therapeutic effect was attributed to the elevated level of phosphatidylserine(PS)upon the injection of MSCs or DMSCs.The direct administration of PS liposomes(PSLs)mimic apoptotic cell fragments also exerted the protective effects as MSCs and DMSCs.The Mer tyrosine kinase(MerTK)deficiency or the knockout of chemokine receptor C-C motif chemokine receptor 2(CCR2)reversed these protective effects of MSCs or DMSCs.These results revealed that DMSCs alone in the therapeutic stem cell preparation or the apoptotic cells induced in vivo may exert the same immunomodulatory property as the'living MSCs preparation'through releasing PS,which was further recognized by MerTK and participated in modulating immune cells.Xuemei He Weiqi Hong Jingyun Yang Hong Lei Tianqi Lu Cai He Zhenfei Bi Xiangyu Pan Yu Liu Lunzhi Dai Wei Wang Canhua Huang Hongxin Deng Xiawei Wei 2021Signal Transduction and Targeted Therapy2021,6,8:6
7Plant microremains provide direct evidence for the functions of stone knives from the Lajia site, northwestern China显示文摘A large number of stone knives have been recovered from Neolithic archaeological sites in East Asia.However, direct evidence regarding the functions of the stone knives has been scarce, and hence, their functions have remained controversial. In this study, we recovered and analysed ancient starch grains and phytoliths from residues adhering to stone knives excavated from the Lajia site, Qinghai Province, northwest China, thus providing direct evidence for the functions of the knives. Our analyses were based on the following:(1) an assemblage of 278identifiable starch grains, representing grains from the stems of foxtail millet(Setaria italica) and broomcorn millet(Panicum miliaceum)(65.1 % of the total) and the stems of Hordeum and Triticum species(3.6 % of the total), and(2) an assemblage of 361 identifiable phytoliths,the majority of which were from the stems and leaves of plants such as Panicoideae and related taxa(96 % of the total). Our study demonstrates that one of the functions of the stone knives was the harvesting crops. In addition, a few starch grains from food legumes and roots(3.4 % of the total) indicate that the stone knives were also likely used to process, peel and cut some foods.Zhikun Ma Quan Li Xiujia Huan Xiaoyan Yang Jingyun Zheng Maolin Ye 2014Chinese Science Bulletin2014,59,11:5
8Targeting folate receptorβpositive tumor-associated macrophages in lung cancer with a folate-modified liposomal complex显示文摘Tumor-associated macrophages(TAMs)facilitate cancer progression by promoting tumor invasion,angiogenesis,metastasis,inflammatory responses,and immunosuppression.Folate receptorβ(FRβ)is overexpressed in TAMs.However,the clinical significance of FRβ-positive macrophages in lung cancer remains poorly understood.In this study,we verified that FRβoverexpression in lung cancer TAMs was associated with poor prognosis.We utilized a folate-modified lipoplex comprising a folatemodified liposome(F-PLP)delivering a BIM-S plasmid to target both lung cancer cells and FRβ-positive macrophages in the tumor microenvironment.Transfection of LL/2 cells and MH-S cells with F-PLP/pBIM induced cell apoptosis.Injection of F-PLP/pBIM into LL/2 and A549 lung cancer models significantly depleted FRβ-positive macrophages and reduced tumor growth.Treatment of tumor-bearing mice with F-PLP/pBIM significantly inhibited tumor growth in vivo by inducing tumor cell and macrophage apoptosis,reducing tumor proliferation,and inhibiting tumor angiogenesis.In addition,a preliminary safety evaluation demonstrated a good safety profile of F-PLP/pBIM as a gene therapy administered intravenously.This work describes a novel application of lipoplexes in lung cancer targeted therapy that influences the tumor microenvironment by targeting TAMs.Yan Tie Heng Zheng Zhiyao He Jingyun Yang Bin Shao Li Liu Min Luo Xia Yuan Yu Liu Xiangxian Zhang Hongyi Li Min Wu Xiawei Wei 2020Signal Transduction and Targeted Therapy2020,5,1:4
9Identification and characterization of two human immunodeficiency virus type 1 unique recombinant forms from Yunnan, China显示文摘Dear Editor,Recombination contributes greatly to the diversity of human immunodeficiency virus type 1(HIV-1).A large number of recombinant strains have been found in China,particularly in Yunnan,which is considered the HIV-1 epicenter of China.Surveillance of unique recombinant forms is helpful for prediction of new circulating recombinant forms.In this study,we identified twoJianjian Li Lin Li Shaomin Yang Jingyun Li Mi Zhang Cuixian Yang Jiafa Liu Huiqin Li 2016Virologica Sinica2016,31,2:4
10DBP formation from degradation of DEET and ibuprofen by UV/chlorine process and subsequent post-chlorination显示文摘The formation of disinfection by-products(DBPs) from the degradation of N,N-diethyl-3-methyl benzoyl amide(DEET) and ibuprofen(IBP) by the ultraviolet irradiation(UV)/chlorine process and subsequent post-chlorination was investigated and compared with the UV/H_2O_2 process.The pseudo first-order rate constants of the degradation of DEET and IBP by the UV/chlorine process were 2 and 3.1 times higher than those by the UV/H_2O_2 process, respectively, under the tested conditions. This was due to the significant contributions of both reactive chlorine species U(RCS) and hydroxyl radicals(HO) in the UV/chlorine process. Trichloromethane, 1,1,1-trichloro-2-propanone and dichloroacetic acid were the major known DBPs formed after 90% of both DEET and IBP that were degraded by the UV/chlorine process. Their yields increased by over 50%after subsequent 1-day post-chlorination. The detected DBPs after the degradation of DEET and IBP comprised 13.5% and 19.8% of total organic chlorine(TOCl), respectively, and the proportions increased to 19.8% and 33.9% after subsequent chlorination, respectively. In comparison to the UV/H_2O_2 process accompanied with post-chlorination, the formation of DBPs and TOCl in the UV/chlorine process together with post-chlorination was 5%–63% higher,Ulikely due to the generation of more DBP precursors from the attack of RCS, in addition to HO.Ehsan Aghdam Yingying Xiang Jianliang Sun Chii Shang Xin Yang Jingyun Fang 2017Journal of Environmental Sciences2017,29,8:3
11Evaluation of multidecadal and longer-term temperature changes since 850 CE based on Northern Hemisphere proxy-based reconstructions and model simulations显示文摘The temperature variability over multidecadal and longer timescales(e.g., the cold epochs in the late 15 th, 17 th, and early 19 th centuries) is significant and dominant in the millennium-long, large-scale reconstructions and model simulations;however, their temporal patterns in the reconstructed and simulated temperature series are not well understood and require a detailed assessment and comparison. Here, we compare the reconstructed and simulated temperature series for the Northern Hemisphere(NH) at multidecadal and longer-term timescales(>30 years) by evaluating their covariance, climate sensitivity and amplitude of temperature changes. We found that covariances between different reconstructions or between reconstructions and simulations are generally high for the whole period of 850–1999 CE, due to their similar long-term temporal patterns. However,covariances between different reconstructions or between reconstructions and simulations steadily decline as time series extends further back in time, becoming particularly small during Medieval times. This is related to the large uncetainties in the reconstructions caused by the decreased number of proxy records and sample duplication during the pre-instrumental periods.Reconstructions based solely on tree-ring data show higher skill than multiproxy reconstructions in capturing the amplitude of volcanic cooling simulated by models. Meanwhile, climate models have a shorter recovery(i.e., lag) in response to the cooling caused by volcanic eruptions and solar activity minima, implying the lack of some important feedback mechanisms between external forcing and internal climate processes in climate models. Amplitudes of temperature variations in the latest published tree-ring reconstructions are comparable to those of the multiproxy reconstructions. We found that the temperature difference between the Medieval Climate Anomaly(950–1250 CE) and the Little Ice Age(1450–1850 CE) is generally larger in proxybased reconstructions than in model simulations, but the reason is unclear.Jianglin WANG Bao YANG Jingyun ZHENG Xuezhen ZHANG Zhiyuan WANG Miao FANG Feng SHI Jingjing LIU 2020Science China Earth Sciences2020,63,8:3
12Reconstruction of the starting time series of rainy season in Yunnan and the evolvement of summer monsoon during 1711-1982显示文摘According to the textual research into the historical documents dominated by ar- chives yearly, as well as the verification with several other kinds of data, the later or earlier starting time of the rainy seasons in Yunnan during 1711–1982 has been reconstructed. The analysis indicates that there are obvious fluctuations in the starting date of the rainy seasons in Yunnan in a year or years, and long fluctuation on the decadal scale. The rainy season comes earlier in the early 18th century, later in the 19th century and earlier again in the 20th century. This reflects to a certain degree the gradual change of the summer monsoon in Yunnan. There exists an obvious quasi-3 years cycle, which is related to El-Nino’s quasi-3 years cycle, and a 11.3-year cycle which is notably related to the 11-year cycle of the solar activity of starting date of the rainy seasons in Yunnan. Meanwhile, the dissertation finds that the El-Nino is very important to the starting date of the rainy seasons in Yunnan. The starting date of the rainy seasons in Yunnan often comes later or normally in the year of El-Nino. However, there is an obvious imperfect period in such influence, which in turn may mean that there is a certain fluctuation in the effect of ENSO on Asian summer monsoon.YANG Yuda MAN Zhimin ZHENG Jingyun 2007Journal of Geographical Sciences2007,17,2:2
13Artificial intelligence-assisted automatic and index-based microbial single-cell sorting system for One-Cell-One-Tube显示文摘Identification,sorting,and sequencing of individual cells directly from in situ samples have great potential for in-depth analysis of the structure and function of microbiomes.In this work,based on an artificial intelligence(AI)-assisted object detection model for cell phenotype screening and a cross-interface contact method for single-cell exporting,we developed an automatic and index-based system called EasySort AUTO,where individual microbial cells are sorted and then packaged in a microdroplet and automatically exported in a precisely indexed,“One-Cell-One-Tube”manner.The target cell is automatically identified based on an AI-assisted object detection model and then mobilized via an optical tweezer for sorting.Then,a crossinterface contact microfluidic printing method that we developed enables the automated transfer of cells from the chip to the tube,which leads to coupling with subsequent single-cell culture or sequencing.The efficiency of the system for single-cell printing is>93%.The throughput of the system for single-cell printing is~120 cells/h.Moreover,>80%of single cells of both yeast and Escherichia coli are culturable,suggesting the superior preservation of cell viability during sorting.Finally,AI-assisted object detection supports automated sorting of target cells with high accuracy from mixed yeast samples,which was validated by downstream single-cell proliferation assays.The automation,index maintenance,and vitality preservation of EasySort AUTO suggest its excellent application potential for single-cell sorting.Zhidian Diao Lingyan Kan Yilong Zhao Jingyun Song Chen Wang Yang Liu Fengli Zhang Teng Xu Rongze Chen Xixian Wang Xiaoyan Jing Jian Xu Yuandong Li Bo Ma 2022mLife2022,1,4:2
14Hollow Gradient-Structured Iron-Anchored Carbon Nanospheres for Enhanced Electromagnetic Wave Absorption显示文摘In the present paper,a microwave absorber with nanoscale gradient structure was proposed for enhancing the electromagnetic absorption performance.The inorganic-organic competitive coating strategy was employed,which can effectively adjust the thermodynamic and kinetic reactions of iron ions during the solvothermal process.As a result,Fe nanoparticles can be gradually decreased from the inner side to the surface across the hollow carbon shell.The results reveal that it offers an outstanding reflection loss value in combination with broadband wave absorption and flexible adjustment ability,which is superior to other relative graded distribution structures and satisfied with the requirements of lightweight equipment.In addition,this work elucidates the intrinsic microwave regulation mechanism of the multiscale hybrid electromagnetic wave absorber.The excellent impedance matching and moderate dielectric parameters are exhibited to be the dominative factors for the promotion of microwave absorption performance of the optimized materials.This strategy to prepare gradient-distributed microwave absorbing materials initiates a new way for designing and fabricating wave absorber with excellent impedance matching property in practical applications.Cao Wu Jing Wang Xiaohang Zhang Lixing Kang Xun Cao Yongyi Zhang Yutao Niu Yingying Yu Huili Fu Zongjie Shen Kunjie Wu Zhenzhong Yong Jingyun Zou Bin Wang Zhou Chen Zhengpeng Yang Qingwen Li 2023Nano-Micro Letters2023,15,1:2
15Diagnosis of pancreatic neoplasia with EUS and FNA: a report of accuracy显示文摘Brian G. Turner Sevdenur Cizginer Deepak Agarwal Jingyun Yang Martha Bishop Pitman William R. Brugge 2010Gastrointestinal Endoscopy2010,,1:2
16Histones released by NETosis enhance the infectivity of SARS-CoV-2 by bridging the spike protein subunit 2 and sialic acid on host cells显示文摘Neutrophil extracellular traps(NETs)can capture and kill viruses,such as influenza viruses,human immunodeficiency virus(HIV),and respiratory syncytial virus(RSV),thus contributing to host defense.Contrary to our expectation,we show here that the histones released by NETosis enhance the infectivity of SARS-CoV-2,as found by using live SARS-CoV-2 and two pseudovirus systems as well as a mouse model.The histone H3 or H4 selectively binds to subunit 2 of the spike(S)protein,as shown by a biochemical binding assay,surface plasmon resonance and binding energy calculation as well as the construction of a mutant S protein by replacing four acidic amino acids.Sialic acid on the host cell surface is the key molecule to which histones bridge subunit 2 of the S protein.Moreover,histones enhance cell-cell fusion.Finally,treatment with an inhibitor of NETosis,histone H3 or H4,or sialic acid notably affected the levels of sgRNA copies and the number of apoptotic cells in a mouse model.These findings suggest that SARS-CoV-2 could hijack histones from neutrophil NETosis to promote its host cell attachment and entry process and may be important in exploring pathogenesis and possible strategies to develop new effective therapies for COVID-19.Weiqi Hong Jingyun Yang Jun Zou Zhenfei Bi Cai He Hong Lei Xuemei He Xue Li Aqu Alu Wenyan Ren Zeng Wang Xiaohua Jiang Kunhong Zhong Guowen Jia Yun Yang Wenhai Yu Qing Huang Mengli Yang Yanan Zhou Yuan Zhao Dexuan Kuang Junbin Wang Haixuan Wang Siyuan Chen Min Luo Ziqi Zhang Tiangi Lu Li Chen Haiying Que Zhiyao He Qiu Sun Wei Wang Guobo Shen Guangwen Lu Zhiwei Zhao Li Yang Jinliang Yang Zhenling Wang Jiong Li Xiangrong Song Lunzhi Dai Chong Chen Jia Geng Maling Gou Lu Chen Haohao Dong Yong Peng Canhua Huang Zhiyong Qian Wei Cheng Changfa Fan Yuquan Wei Zhaoming Su Aiping Tong Shuaiyao Lu Xiaozhong Peng Xiawei Wei 2022Cellular & Molecular Immunology2022,19,5:2
17Two novel terpyridine-based chromophores with donor-acceptor structural model containing modified triphenylamine moiety: Synthesis, crystal structures and two-photon absorption properties显示文摘Two novel terpyridine-based chromophores with D-A (D = donor, A = acceptor) structural model containing modified triphenylamine moiety (L1 and L2 ) have been conveniently synthesized via formylation and reduction in satisfactory yields, and fully characterized. The single crystals of them were obtained and determined by X-ray diffraction analysis. The relationships between structure and photophysical properties of the two chromophores were investigated both experimentally and theoretically. The measured maximum TPA cross-sections per molecular weight (δmax /MW) of the chromophores are 0.63 GM/(g mol) (L1) and 0.72 GM/(g mol) (L2), respectively, in DMF as a high polar solvent. The results indicate that the value of δmax/MW could be well tuned by the intramolecular charge transfer (ICT), which could be realized by introducing additional elecron-donor/acceptor groups.LIU Jie ZHANG Qiong DING HongJuan ZHANG Jun TAN JingYun WANG ChuanKui WU JieYing LI ShengLi ZHOU HongPing YANG JiaXiang TIAN YuPeng 2013Science China Chemistry2013,56,9:2
18Global patterns and climatic drivers of above-and belowground net primary productivity in grasslands显示文摘Understanding patterns and determinants of net primary productivity(NPP)in global grasslands is ongoing challenges,especially for belowground NPP(BNPP)and its fraction(fBNPP).By developing a comprehensive field-based dataset,we revealed that,along with gradients of mean annual precipitation,actual evapotranspiration,and aridity,aboveground NPP(ANPP),BNPP,and total NPP(TNPP)exhibited hump-shaped patterns,whereas fBNPPshowed an opposite trend.ANPP and TNPP showed positive correlations with mean annual temperature,but fBNPPwas negatively correlated with it.The relationship between BNPP and climatic factors was considerably weak,indicating that BNPP was relatively stable regardless of the climate conditions.We also observed that the sensitivities of ANPP and BNPP to interannual temperature variability and those of BNPP to interannual precipitation fluctuations exhibited large variations among different study sites,and differed from those at the spatial scale.In contrast,the temporal sensitivities of ANPP to interannual precipitation variability were highly similar across all the individual sites and much smaller than those at the spatial scale.Overall,these results highlight that precipitation,temperature and evapotranspiration all play vital roles in shaping ANPP pattern and its partitioning to belowground and that the patterns of BNPP along climatic gradients do not mirror those of the ANPP.Yuanfeng Sun Yuanhe Yang Xia Zhao Zhiyao Tang Shaopeng Wang Jingyun Fang 2021Science China(Life Sciences)2021,64,5:2
19Identifying factors that influence soil heavy metals by using categorical regression analysis:A case study in Beijing,China显示文摘Identifying the factors that influence the heavy metal contents of soil could reveal the sources of soil heavy metal pollution.In this study,a categorical regression was used to identify the factors that influence soil heavy metals.First,environmental factors were associated with soil heavy metal data,and then,the degree of influence of different factors on the soil heavy metal contents in Beijing was analyzed using a categorical regression.The results showed that the soil parent material,soil type,land use type,and industrial activity were the main influencing factors,which suggested that these four factors were important sources of soil heavy metals in Beijing.In addition,population density had a certain influence on the soil Pb and Zn contents.The distribution of soil As,Cd,Pb,and Zn was markedly influenced by interactions,such as traffic activity and land use type,industrial activity and population density.The spatial distribution of soil heavy metal hotspots corresponded well with the influencing factors,such as industrial activity,population density,and soil parent material.In this study,the main factors affecting soil heavy metals were identified,and the degree of their influence was ranked.A categorical regression represents a suitable method for identifying the factors that influence soil heavy metal contents and could be used to study the genetic process of regional soil heavy metal pollution.Jun Yang Jingyun Wang Pengwei Qiao Yuanming Zheng Junxing Yang Tongbin Chen Mei Lei Xiaoming Wan Xiaoyong Zhou 2020Frontiers of Environmental Science & Engineering2020,14,3:1
20Formation of carbonaceous and nitrogenous disinfection by - products from the chlorination of Microcystis aeruginosa显示文摘Fang Jingyun Ma Jun Yang Xin 2010Water Research2010,44,6:1
返回顶部 每页显示:
共4页 首页 上一页 第1页 下一页 末页 /4 跳转

网站首页 | 关于我们 | 联系我们 | 产品服务 | 客服中心 | 广告服务 | 版权声明 | 网站联盟 | 友情链接 | 售卡网点

版权所有© 渝B2-20050021-1 渝公网安备 50019002500403号 违法和不良信息举报中心

互联网出版许可证 新出网证(渝)字10号 全国400电话 - 免长途话费