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| 1 | Comparison of Ozone and PM2.5 Concentrations over Urban,Suburban,and Background Sites in China显示文摘Surface ozone(O3)and fine particulate matter(PM2.5)are dominant air pollutants in China.Concentrations of these pollutants can show significant differences between urban and nonurban areas.However,such contrast has never been explored on the country level.This study investigates the spatiotemporal characteristics of urban-to-suburban and urban-tobackground difference for O3(Δ[O3])and PM2.5(Δ[PM2.5])concentrations in China using monitoring data from 1171 urban,110 suburban,and 15 background sites built by the China National Environmental Monitoring Center(CNEMC).On the annual mean basis,the urban-to-suburbanΔ[O3]is−3.7 ppbv in Beijing-Tianjin-Hebei,1.0 ppbv in the Yangtze River Delta,−3.5 ppbv in the Pearl River Delta,and−3.8 ppbv in the Sichuan Basin.On the contrary,the urban-to-suburbanΔ[PM2.5]is 15.8,−0.3,3.5 and 2.4μg m^−3 in those areas,respectively.The urban-to-suburban contrast is more significant in winter for bothΔ[O3]andΔ[PM2.5].In eastern China,urban-to-background differences are also moderate during summer,with−5.1 to 6.8 ppbv forΔ[O3]and−0.1 to 22.5μg m^−3 forΔ[PM2.5].However,such contrasts are much larger in winter,with−22.2 to 5.5 ppbv forΔ[O3]and 3.1 to 82.3μg m^−3 forΔ[PM2.5].Since the urban region accounts for only 2%of the whole country’s area,the urban-dominant air quality data from the CNEMC network may overestimate winter[PM2.5]but underestimate winter[O3]over the vast domain of China.The study suggests that the CNEMC monitoring data should be used with caution for evaluating chemical models and assessing ecosystem health,which require more data outside urban areas. | Lan GAO Xu YUE Xiaoyan MENG Li DU Yadong LEI Chenguang TIAN Liang QIU | 2020 | Advances in Atmospheric Sciences2020，37，12： | 5 |
| 2 | The heterogeneity of islet autoantibodies and the progression of islet failure in type 1 diabetic patients显示文摘Type 1 diabetes mellitus is heterogeneous in many facets. The patients suffered from type 1 diabetes present several levels of islet function as well as variable number and type of islet-specific autoantibodies. This study was to investigate prevalence and heterogeneity of the islet autoantibodies and clinical phenotypes of type 1 diabetes mellitus; and also discussed the process of islet failure and its risk factors in Chinese type 1 diabetic patients. A total of 1,291 type 1 diabetic patients were enrolled in this study. Demographic information was collected. Laboratory tests including mixed-meal tolerance test, human leukocyte antigen alleles, hemoglobin A1 c, lipids, thyroid function and islet autoantibodies were conducted. The frequency of islet-specific autoantibody in newly diagnosed T1 DM patients(duration shorter than half year) was 73% in East China. According to binary logistic regressions, autoantibody positivity, longer duration and lower Body Mass Index were the risk factors of islet failure. As the disease developed, autoantibodies against glutamic acid decarboxylase declined as well as the other two autoantibodies against zinc transporter 8 and islet antigen 2. The decrease of autoantibodies was positively correlated with aggressive beta cell destruction. Autoantibodies can facilitate the identification of classic T1 DM from other subtypes and predict the progression of islet failure. As there were obvious heterogeneity in autoantibodies and clinical manifestation in different phenotypes of the disease, we should take more factors into consideration when identifying type 1 diabetes mellitus. | Jin Liu Lingling Bian Li Ji Yang Chen Heng Chen Yong Gu Bingqin Ma Wei Gu Xinyu Xu Yun Shi Jian Wang Dalong Zhu Zilin Sun Jianhua Ma Hui Jin Xing Shi Heng Miao Bing Xin Yan Zhu Zhenwen Zhang Ruifang Bu Lan Xu Guangde Shi Wei Tang Wei Li Dongmei Zhou Jun Liang Xingbo Cheng Bimin Shi Jixiang Dong Ji Hu Chen Fang Shao Zhong Weinan Yu Weiping Lu Chenguang Wu Li Qian Jiancheng Yu Jialin Gao Xiaoqiang Fei Qingqing Zhang Xueqin Wang Shiwei Cui Jinluo Cheng Ning Xu Guofeng Wang Guoqing Han Chunrong Xu Yun Xie Minmin An Wei Zhang Zhixiao Wang Yun Cai Qi Fu Yu Fu Shuai Zheng Fan Yang Qingfang Hu Hao Dai Yu Jin Zheng Zhang Kuanfeng Xu Yifan Li Jie Shen Hongwen Zhou Wei He Xuqin Zheng Xiao Han Liping Yu Jinxiong She Mei Zhang Tao Yang | 2016 | Science China(Life Sciences)2016，59，9： | 5 |
| 3 | Stipa steppes in scantily explored regions of the tibetan Plateau:classification,community characteristics and climatic distribution patterns显示文摘Aims As a unique geographical unit of the earth,the tibetan Plateau is extensively covered by various Stipa communities.However,their vegetation features have not been reported systematically till now,especially in some scantily explored regions.In this study,we endeavor to reveal the community types,quantitative charac-teristics and climatic distribution patterns of Stipa steppes in these areas based on primary relevés obtained from fieldwork.Methods We collected a total of 223 plots in 79 study sites in the Changthang Plateau and the Yarlung Zangbo Valley,ranging from 79°E to 91°E.the categories of Stipa formations were identified according to the classification scheme in Vegetation of China and then verified by Nonmetric Multidimensional Scaling.We performed detrended correspondence analysis and detrended canonical correspondence analysis to hunt for the alteration of Stipa communities along the precipitation gradient.Quantitative characteristics including species richness,coverage,biomass as well as importance values(IV)of dominant species were calcu-lated and visualized,respectively.Important Findings Stipa steppes in scantily explored regions of the tibetan Plateau are classified into 11 formations but major formations are rather limited in number.Formation(form.)Stipa purpurea is the most widespread Stipa assemblages not only in scantily explored regions but also across the whole tibetan Plateau.the characteristics of Stipa com-munities,including coverage,species richness,productivity and IV of dominant species,demonstrate the features of typical alpine steppes on the tibetan Plateau.Precipitation proves to be the prime climatic factor controlling the distribution patterns of Stipa assemblages.Form.Stipa subsessiliflora var.basiplumosa and form.Stipa glareosa normally distribute in arid habitats,but rainfall for the former is of greater variance.Form.Stipa roborowskyi and form.Stipa capillacea favor moderately moist environment.Form.Stipa purpurea and form.Stipa roborowskyi can tolerate a fairly broad range of precipitation. | Haiwei Zhao Ke Guo Yao Yang Changcheng Liu Liqing Zhao Xianguo Qiao Dongjie Hou Chenguang Gao | 2018 | Journal of Plant Ecology2018，11，4： | 4 |
| 4 | Distribution characteristics and indicator significance of Dechloranes in multi-matrices at Ny-lesund in the Arctic显示文摘In recent years, Dechloranes have been widely detected in the environment around the world.However, understanding and knowledge of Dechloranes in remote regions, such as the Arctic,remain lacking. Therefore, the concentrations of 5 Dechloranes in surface seawater, sediment,soil, moss, and dung collected from Ny-lesund in the Arctic were measured with the concentrations 93 pg/L, 342, 325, 1.4, and 258 pg/g, respectively, which were much lower than those in Asian and European regions. The mean ratios of anti-Dechlorane Plus(DP) to total DP(fanti) in seawater, sediment, soil, moss, dung, and atmospheric samples were 0.36, 0.21, 0.18,0.27, 0.66, and 0.43, respectively. Results suggested that the main source of DP in seawater,sediment, soil, and moss was long-range atmospheric transport. However, the ratio identified in dung was different, for which the migration behavior of the organism is probably the main source of DP. | Guangshui Na Wei Wei Shiyao Zhou Hui Gao Xindong Ma Lina Qiu Linke Ge Chenguang Bao Ziwei Yao | 2015 | Journal of Environmental Sciences2015，27，2： | 3 |
| 5 | Recombinant adenovirus-mediated overexpression of 3β-hydroxysteroid-Δ24 reductase显示文摘3β-Hydroxysteroid-Δ24 reductase(DHCR24) is a multifunctional enzyme that localizes to the endoplasmic reticulum and has neuroprotective and cholesterol-synthesizing activities. DHCR24 overexpression confers neuroprotection against apoptosis caused by amyloid β deposition. The present study aimed to construct two recombinant adenoviruses driving DHCR24 expression specifically in neurons. Two SYN1 promoter DNA fragments were obtained from human(h) and rat(r). Recombinant Ad-r(h)SYN1-DHCR24 was transfected into AD-293, N2A(mouse neuroblastoma), and MIN6(mouse pancreatic carcinoma) cells. Western blot analysis showed DHCR24 was specially expressed in 293 and N2A cells, but no specific band was found in MIN6 cells. This demonstrates that the recombinant adenoviruses successfully express DHCR24, and no expression is observed in non-neuronal cells. TUNEL assay results showed apoptosis was inhibited in adenovirus-transfected neurons. Detecting reactive oxygen species by immunofluorescence, we found that adenovirus transfection inhibits apoptosis through scavenging excess reactive oxygen species. Our findings show that the recombinant DHCR24 adenoviruses induce neuron-specific DHCR24 expression, and thereby lay the foundation for further studies on DHCR24 gene therapy for Alzheimer's disease. | Xiuli Lu Dan Jia Chenguang Zhao Weiqi Wang Ting Liu Shuchao Chen Xiaoping Quan Deliang Sun Bing Gao | 2014 | Neural Regeneration Research2014，9，5： | 1 |
| 6 | Exome sequencing identifies rare mutations of LDLR and QTRT1 conferring risk for early-onset coronary artery disease in Chinese显示文摘Despite the advances made over the past decades,the known loci for coronary artery disease(CAD)still only explain<20%of the genetic variation in risk[1,2].The known loci with the strongest effects usually confer a 20%-37%increased CAD risk and the most loci modulate risk by≤10%[1].While most of the current data are from European populations,the use of trans-ethnic analyses could be helpful to identify additional loci.Genetic inheritance may impose a high burden on early-onset coronary artery disease(EOCAD). | Kang Yao Yuxiang Dai Juan Shen Yi Wang Huanjie Yang Runda Wu Qijun Liao Hongyi Wu Xiaodong Fang Shalaimaiti Shali Lili Xu Meng Hao Chenhao Lin Zhonghan Sun Yilian Liu Mengxin Li Zhen Wang Qiang Gao Shuning Zhang Chenguang Li Wei Gao Lei Ge Yunzeng Zou Aijun Sun Juying Qian Li Jin Shangyu Hong Yan Zheng Junbo Ge | 2022 | National Science Review2022，9，8： | 1 |
| 7 | β-decay Study of Tz=-3/2Proton-rich Nucleus 29S显示文摘The exotic decay of nuclei far from the stability has recently become a hot topic of nuclear structure research.The nuclide 29S is not well investigated in the A=4n+1,Tz=-3/2series of strong+β-delayed proton precursors.The decay schemes of these nuclei are characterized | ZHONG Fupeng XU Xinxing LIN Chengjian WANG Jiansong LI Zhihuan YANG Lei MA Nanru WANG Dongxi WEN Peiwei SUN Lijie WU Hongyi LUO Diwen WU Chenguang JIANG Ying LIU Yang ZANG Hongliang LIANG Pengfei LI Pengjie LI Xiaojing ZHAO Qingqing SHI Guozhu MA Junbing MA Peng YU Gongming Dipikap Patel BAI Zhen YANG Feng JIA Huiming ZHANG Huanqiao WANG Jianguo YANG Yanyun MA Weihu HU Qiang JIN Shuya ZHOU Xiaohong LI Ren HOU Dongsheng LIU Minliang HU Zhengguo MA Xinwen YANG Weiqing GAO Zhihao DUAN Fangfang YU Yuechao WANG Yufeng WANG Peng ZHOU Qingwu CUI Danteng WANG Xiang HU Liyuan PAN Min ZHANG Gaolong WANG Xiaoyu | 2017 | Annual Report of China Institute of Atomic Energy2017，，1： | 0 |
| 8 | Seamless Prediction in China: A Review显示文摘Seamless prediction is a weather-climate integrated prediction covering multiple time scales that include days,weeks,months,seasons,years,and decades.Seamless prediction can provide different industries with information such as weather conditions and climate variations from the next few days to years,which have important impacts on economic and social development and important reference value for short-,medium-and long-term decision-making and planning of the country.Therefore,seamless prediction has received widespread attention from the international scientific community recently.As Chinese scientists have also carried out relevant research,this paper reviews the research in China on developments and applications of seamless prediction methods and prediction systems in recent years.Among them,the main progress of seamless prediction methods studies is reviewed from four aspects:short-and medium-range weather forecasting,subseasonal-to-seasonal,seasonal-to-interannual,and decadal climate prediction.In terms of development and application of seamless prediction systems,the main achievements made by meteorological operational departments,scientific institutes,and universities in China in recent years are reviewed.Finally,some of the issues in seamless prediction that need further study are discussed. | Hong-Li REN Qing BAO Chenguang ZHOU Jie WU Li GAO Lin WANG Jieru MA Yao TANG Yangke LIU Yujun WANG Zuosen ZHAO | 2023 | Advances in Atmospheric Sciences2023，40，8： | 0 |
| 9 | Detailed seafloor geomorphology of the western region of the North Yellow Sea,China:The result of Holocene erosional and depositional processes sculpting the offshore continental shelf显示文摘High-resolution multi-beam/single-beam bathymetric data and seismic profiling data from the latest surveys are used to map and interpret the detailed seafloor geomorphology of the western region of the North Yellow Sea(NYS),China.The mapping area covers 156410 km^(2),and incorporates a flat shelf plain,subaqueous accumulation shoals,tidal scouring troughs,and tidal sand ridge groups.Offshore areas with water depths less than 50 m in the western region of the NYS are mainly covered by thick,loose sediments,forming wide spread accumulation geomorphological features;these include the Liaodong Peninsula subaqueous accumulation system containing shoals and rugged scouring troughs,and the large mud wedge of the Shandong Peninsula.In the central part of the NYS,there is a relatively flat residual shelf plain with coarser sediment deposits.This flat shelf plain has a water depth larger than 50 m and a thin layer of sediment,on which there is a large pockmark field caused by seafloor seepage.These geomorphological structures indicate that modern sedimentary processes are the main driving force controlling the sculpture of the current seafloor surface landform.Extensive strong tidal current systems and abundant sediment sources provide the critical external forces and essential conditions for the formation of seafloor geomorphology.The tectonic basement controls the macroscopic morphological shape of the NYS,but is reflected very little in the seafloor geomorphic elements.Our results provide a detailed seafloor geomorphological map of the western region of the NYS,an area that has not previously mapped and also provide a scientific framework for further research into offshore seafloor geomorphology,shelf sedimentary processes,and submarine engineering construction in this region. | Xiaoyu Liu Yilan Chen Chenguang Liu Qiuhua Tang Yanhong Wang Shan Gao | 2022 | Acta Oceanologica Sinica2022，41，12： | 0 |
| 10 | Microstructural evolution and mechanical properties of in situ nano Ta_(4)HfC_(5) reinforced SiBCN composite ceramics显示文摘The in situ nano Ta_(4)HfC_(5) reinforced SiBCN-Ta_(4)HfC_(5) composite ceramics were prepared by a combination of two-step mechanical alloying and reactive hot-pressing sintering.The microstructural evolution and mechanical properties of the resulting SiBCN-Ta_(4)HfC_(5) were studied.After the first-step milling of 30 h,the raw materials of TaC and HfC underwent crushing,cold sintering,and short-range interdiffusion to finally obtain the high pure nano Ta_(4)HfC_(5).A hybrid structure of amorphous SiBCN and nano Ta_(4)HfC_(5) was obtained by adopting a second-step ball-milling.After reactive hot-pressing sintering,amorphous SiBCN has crystallized to 3C-SiC,6H-SiC,and turbostratic BN(C)phases and Ta_(4)HfC_(5) retained the form of the nanostructure.With the in situ generations of 2.5 wt% Ta_(4)HfC_(5),Ta_(4)HfC_(5) is preferentially distributed within the turbostratic BN(C);however,as Ta_(4)HfC_(5) content further raised to 10 wt%,it mainly distributed in the grain-boundary of BN(C) and SiC.The introduction of Ta_(4)HfC_(5) nanocrystals can effectively improve the flexural strength and fracture toughness of SiBCN ceramics,reaching to 344.1 MPa and 4.52 MPa·m^(1/2),respectively.This work has solved the problems of uneven distribution of ultra-high temperature phases in the ceramic matrix,which is beneficial to the real applications of SiBCN ceramics. | Bingzhu WANG Daxin LI Zhihua YANG Dechang JIA Jingyi GUAN Hao PENG Delong CAI Peigang HE Xiaoming DUAN Yu ZHOU Tao ZHANG Chenguang GAO | 2020 | Journal of Advanced Ceramics2020，9，6： | 0 |
| 11 | Highly Fluorescent Semiconducting Two-Dimensional Conjugated Polymer Films Achieved by Side-Chain Engineering Showing Large Exciton Diffusion Length显示文摘Semiconducting two-dimensional conjugated polymers(2DCPs)with strong fluorescence emission have great potential for various optoelectronic applications.However,it is enormously challenging to achieve this goal due to the significant compact interlayerπ-πstacking-induced quenching effect in these systems.In this work,we found that highly fluorescent semiconducting 2DCPs can be prepared through an effective side-chain engineering approach in which interlayer spacers are introduced to reduce the fluorescence quenching effect.The obtained two truxene-based 2DCP films that,along with-C6H13 and-C_(12)H_(25)alkyl side chains as interlayer spacers both demonstrate superior fluorescence properties with a high photoluminescence quantum yield of 5.6%and 14.6%,respectively.These are among the highest values currently reported for 2DCP films.Moreover,an ultralong isotropic quasi-twodimensional exciton diffusion length constrained in the plane with its highest value approaching 110 nm was revealed by the transient photoluminescence microscopy technique,suggesting that theπ-conjugated structure in these truxene-based 2DCP films has effectively been extended.This work can enable a broad exploration of highly fluorescent semiconducting 2DCP films for more deeply fundamental properties and optoelectronic device applications. | Yongshuai Wang Qing Zhang Xiao-Ze Li Zhibin Shu Yihan Zhang Can Gao Yang Li Hao Liu Chenguang Li Hong-Hua Fang Hong-Bo Sun Xiaotao Zhang Wenping Hu Huanli Dong | 2023 | CCS Chemistry2023，5，10： | 0 |
| 12 | Effective and selective separation of perrhenate from acidic wastewater by super-stable,superhydrophobic,and recyclable biosorbent显示文摘The recovery of scattered metal ions such as perrhenate(Re(VII))from industrial effluents has enormous economic benefits and promotes resource reuse.Nanoscale-metal/biochar hybrid biosorbents are attractive for recovery but are limited by their insufficient stability and low selectivity in harsh environments.Herein,a superstable biochar-based biosorbent composed of ZnO nanoparticles with remarkable superhydrophobic features is fabricated,and its adsorption/desorption capabilities toward Re(VII)in strongly acidic aqueous solutions are investigated.The ZnO nanoparticle/biochar hybrid composite(ZBC)exhibits strong acid resistance and high chemical stability,which are attributable to strong C-O-Zn interactions between the biochar and ZnO nanoparticles.Due to the advantages of its hydrolytic stability,superhydrophobicity,and abundance of Zn-O sites,the ZBC proves suitable for the effective and selective separation of Re(VII)from single,binary and multiple ion systems(pH=1),with a maximum sorption capacity of 29.41 mg/g.More importantly,this material also shows good recyclability and reusability,with high adsorption efficiency after six adsorption-desorption cycles.The findings in this work demonstrate that a metal/biochar hybrid composite is a promising sorbent for Re(VII)separation. | Hui Hu Lei Jiang Longli Sun Yanling Gao Tian Wang Chenguang Lv | 2022 | Frontiers of Environmental Science & Engineering2022，16，2： | 0 |
| 13 | PowerDetector:Malicious PowerShell Script Family Classification Based on Multi-Modal Semantic Fusion and Deep Learning显示文摘Power Shell has been widely deployed in fileless malware and advanced persistent threat(APT)attacks due to its high stealthiness and live-off-theland technique.However,existing works mainly focus on deobfuscation and malicious detection,lacking the malicious Power Shell families classification and behavior analysis.Moreover,the state-of-the-art methods fail to capture fine-grained features and semantic relationships,resulting in low robustness and accuracy.To this end,we propose Power Detector,a novel malicious Power Shell script detector based on multimodal semantic fusion and deep learning.Specifically,we design four feature extraction methods to extract key features from character,token,abstract syntax tree(AST),and semantic knowledge graph.Then,we intelligently design four embeddings(i.e.,Char2Vec,Token2Vec,AST2Vec,and Rela2Vec) and construct a multi-modal fusion algorithm to concatenate feature vectors from different views.Finally,we propose a combined model based on transformer and CNN-Bi LSTM to implement Power Shell family detection.Our experiments with five types of Power Shell attacks show that PowerDetector can accurately detect various obfuscated and stealth PowerShell scripts,with a 0.9402 precision,a 0.9358 recall,and a 0.9374 F1-score.Furthermore,through singlemodal and multi-modal comparison experiments,we demonstrate that PowerDetector’s multi-modal embedding and deep learning model can achieve better accuracy and even identify more unknown attacks. | Xiuzhang Yang Guojun Peng Dongni Zhang Yuhang Gao Chenguang Li | 2023 | China Communications2023，20，11： | 0 |
| 14 | Distinct and shared endothermic strategies in the heat producing tissues of tuna and other teleosts显示文摘Although most fishes are ectothermic,some,including tuna and billfish,achieve endothermy through specialized heat producing tissues that are modified muscles.How these heat producing tissues evolved,and whether they share convergent molecular mechanisms,remain unresolved.Here,we generated a high-quality genome from the mackerel tuna(Euthynnus affinis)and investigated the heat producing tissues of this fish by single-nucleus and bulk RNA sequencing.Compared with other teleosts,tuna-specific genetic variation is strongly associated with muscle differentiation.Single-nucleus RNA-seq revealed a high proportion of specific slow skeletal muscle cell subtypes in the heat producing tissues of tuna.Marker genes of this cell subtype are associated with the relative sliding of actin and myosin,suggesting that tuna endothermy is mainly based on shivering thermogenesis.In contrast,cross-species transcriptome analysis indicated that endothermy in billfish relies mainly on nonshivering thermogenesis.Nevertheless,the heat producing tissues of the different species do share some tissue-specific genes,including vascular-related and mitochondrial genes.Overall,although tunas and billfishes differ in their thermogenic strategies,they share similar expression patterns in some respects,highlighting the complexity of convergent evolution. | Baosheng Wu Xueli Gao Mingling Hu Jing Hu Tianming Lan Tingfeng Xue Wenjie Xu Chenglong Zhu Yuan Yuan Jiangmin Zheng Tao Qin Peidong Xin Ye Li Li Gong Chenguang Feng Shunping He Huan Liu Haimeng Li Qing Wang Zhenhua Ma Qiang Qiu Kun Wang | 2023 | Science China(Life Sciences)2023，66，11： | 0 |
| 15 | Assessing the collapse risk of Stipa bungeana grassland in China based on its distribution changes显示文摘The criteria used by International Union for Conservation of Nature(IUCN) for its Red List of Ecosystems(RLE) are the global standards for ecosystem-level risk assessment, and they have been increasingly used for biodiversity conservation. The changed distribution area of an ecosystem is one of the key criteria in such assessments. The Stipa bungeana grassland is one of the most widely distributed grasslands in the warm-temperate semi-arid regions of China. However, the total distribution area of this grassland was noted to have shrunk and become fragmented because of its conversion to cropland and grazing-induced degradation. Following the IUCN-RLE standards, here we analyzed changes in the geographical distribution of this degraded grassland, to evaluate its degradation and risk of collapse. Past(1950-1980) distribution areas were extracted from the Vegetation Map of China(1:1,000,000). Present realizable distribution areas were equated to these past areas minus any habitat area losses. We then predicted the grassland’s present and future(under the Representative Concentration Pathway 8.5 scenario) potential distribution areas using maximum entropy algorithm(MaxEnt), based on field survey data and nine environmental layers. Our results showed that the S. bungeana grassland was mainly distributed in the Loess Plateau, Hexi Corridor, and low altitudes of the Qilian Mountains and Longshou Mountain. This ecosystem occurred mainly on loess soils, kastanozems, steppe aeolian soils and sierozems. Thermal and edaphic factors were the most important factors limiting the distribution of S. bungeana grassland across China. Since 56.1% of its past distribution area(4.9×10~4 km^2) disappeared in the last 50 a, the present realizable distribution area only amounts to 2.2×10~4 km^2. But only 15.7% of its present potential distribution area(14.0×10~4 km^2) is actually occupied by the S. bungeana grassland. The future potential distribution of S. bungeana grassland was predicted to shift towards northwest, and the total area of this ecosystem will shrink by 12.4% over the next 50 a under the most pessimistic climate change scenario. Accordingly, following the IUCN-RLE criteria, we deemed the S. bungeana grassland ecosystem in China to be endangered(EN). Revegetation projects and the establishment of protected areas are recommended as effective ways to avert this looming crisis. This empirical modeling study provides an example of how IUCN-RLE categories and criteria may be valuably used for ecosystem assessments in China and abroad. | QIAO Xianguo GUO Ke LI Guoqing ZHAO Liqing LI Frank Yonghong GAO Chenguang | 2020 | Journal of Arid Land2020，12，2： | 0 |
| 16 | Studies on the rheological, phase morphologic, thermal and mechanical properties of poly(trimethylene terephthalate)/ ethylene propylene diene monomer copolymer grafted with maleic anhydride/metallocene polyethylene blends显示文摘The rheological,phase morphologic,thermal andmechanicalpropertiesofpoly(trimethyleneterephthalate)/metallocene polyethylene(PTT/mPE)blends in the presence of ethylene propylene diene monomer copolymer grafted with maleic anhydride(EPDM-g-MAH)as compatibilizer are studied by means of a capillary rheometer,scanning electron microscopy(SEM),differential scanning calorimetry(DSC)and thermogravimetric analyzer(TGA).Results suggest that the compatibility of PTT/mPE blends is improved greatly after the addition of a compatibilizer.The radius of the dispersed phase in the system decreases greatly when the compatibilizer is added into the blend.When the amount of compatibilizer exceeds 8 wt-%,the size of dispersed phase becomes larger again.This phenomena could be attributed to the higher viscosity of the EPDM-g-MAH phase,which is dispersed more difficulty in the PTT phase of lower viscosity,thus the mixing efficiency is apparently decreased during the melt blending process.Moreover,the melt viscosity of the blend reaches the maximal value in case of 4 wt-%compati-bilizer content,above which it would decrease again.This result is associated with the generation of more and bigger dispersed phase inside the bulk phase,thus the grafting efficiency at the interface is decreased,which could result in lower viscosity.The DSC results suggest that the mPE component shows a nucleating effect,and could increase the overall degree and rate of PTT crystallization,while the addition of a compatibilizer might slightly diminish these effects.In addition,the blend with 4 wt-%compatibilizer shows the best thermal stability.Furthermore,the Izod impact strength and the tensile strength at room temperature of the blend are also markedly improved by the addition of a 4–8 wt-%compatibilizer. | RUN Mingtao SONG Hongzan WANG Yingjin YAO Chenguang GAO Jungang | 2007 | Frontiers of Chemical Science and Engineering2007，1，3： | 0 |
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