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| 1 | Mechanism for the formation of the January 2013 heavy haze pollution episode over central and eastern China显示文摘In January 2013,a long-lasting episode of severe haze occurred in central and eastern China,and it attracted attention from all sectors of society.The process and evolution of haze pollution episodes were observed by the'Forming Mechanism and Control Strategies of Haze in China'group using an intensive aerosol and trace gases campaign that simultaneously obtained data at 11 ground-based observing sites in the CARE-China network.The characteristics and formation mechanism of haze pollution episodes were discussed.Five haze pollution episodes were identified in the Beijing-Tianjin-Hebei(Jing-Jin-Ji)area;the two most severe episodes occurred during 9–15 January and 25–31 January.During these two haze pollution episodes,the maximum hourly PM2.5mass concentrations in Beijing were 680 and 530μg m 3,respectively.The process and evolution of haze pollution episodes in other major cities in the Jing-Jin-Ji area,such as Shijiazhuang and Tianjin were almost the same as those observed in Beijing.The external cause of the severe haze episodes was the unusual atmospheric circulation,the depression of strong cold air activities and the very unfavorable dispersion due to geographical and meteorological conditions.However,the internal cause was the quick secondary transformation of primary gaseous pollutants to secondary aerosols,which contributed to the'explosive growth'and'sustained growth'of PM2.5.Particularly,the abnormally high amount of nitric oxide(NOx)in the haze episodes,produced by fossil fuel combustion and vehicle emissions,played a direct or indirect role in the quick secondary transformation of coal-burning sulphur dioxide(SO2)to sulphate aerosols.Furthermore,gaseous pollutants were transformed into secondary aerosols through heterogeneous reactions on the surface of fine particles,which can change the particle’s size and chemical composition.Consequently,the proportion of secondary inorganic ions,such as sulphate and nitrate,gradually increased,which enhances particle hygroscopicity and thereby accelerating formation of the haze pollution. | WANG YueSi YAO Li WANG LiLi LIU ZiRui JI DongSheng TANG GuiQian ZHANG JunKe SUN Yang HU Bo XIN JinYuan | 2014 | Science China Earth Sciences2014,57,1: | 189 |
| 2 | Role of Epstein-Barr Virus Encoded Latent Membrane Protein 1 in the Carcinogenesis of Nasopharyngeal Carcinoma显示文摘Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1) has been known to have oncogenic properties during latent infection in nasopharyngeal carcinoma (NPC). Our studies focused on the role of LMP1 in NPC, and showed that LMP1 triggers the NF-κB, AP-1 and STAT signaling pathways. Strikingly, LMP1 was found to mediate the formation of a new heterodimer between c-Jun and JunB. Also, we have identified JAK/STAT and PI-PLC-PKC activation triggered by LMP1 through upregulating the expression of JAK3 and enhancing the phosphorylation of STAT. The constitutive activation of these signaling cascades explains LMP1’s ability to induce such a diverse array of morphological and phenotypic effects in cells and provides insight into how LMP1 may induce cell transformation, in which multihit targeted genes in the downstream play an essential role. All signaling cascades triggered by LMP1 ultimately lead to the disruption of the cell cycle: the acceleration of G1/S phase and the arrest of G2/M phase. We also found that LMP1 induced the expression of hTERT and promoted cell immortalization. Importantly, by intervening physical intracellular signal transduction pathways and disturbing the progression of the cell cycle, LMP1, an important oncoprotein encoded by EBV, is thought to be a key modulator in the pathogenesis of NPC. Interfering LMP1 signaling could be a promising strategy to target the malignant phenotype of NPC. | Hui Zheng Lili Li Duosha Hu Xiyun Deng Ya Cao | 2007 | Cellular & Molecular Immunology2007,4,3: | 34 |
| 3 | Variability and reduction of atmospheric pollutants in Beijing and its surrounding area during the Beijing 2008 Olympic Games显示文摘The Beijing-Tianjin-Hebei Atmospheric Environment Monitoring Network was established by the Institute of Atmospheric Physics,Chinese Academy of Sciences.The goals of the network were to monitor and provide warnings of the atmospheric quality in Beijing and its surrounding area during the Beijing 2008 Olympic Games.The results showed that the atmospheric complex pollution exhibited high concentrations of ozone and fine particles and oxidation in summer,with a ubiquitous regional source.The regional mean concentrations of SO2,PM2.5,NO2,and O3_8h max(the maximum daily 8 h mean) and Ox were 22±11,90±40,25±5,136±35 and 112±21 μg/m3 in summer,respectively.During the Olympic Games,the mean concentration of SO2,PM2.5,NO2,O3_8h max,and Ox were 12.5±4,56±28,23±4,114±29,95±17 μg/m3 in the region,respectively,and fell by 51.0%,43.7%,13%,20.2%,and 18.9%,respectively,compared to the prophase mean before the Olympic Games.The concentration of atmospheric pollutants declined significantly and achieved the 'Green Olympics' control goal of air quality.After the Olympic Games,SO2,PM2.5 and NOx increased significantly as the temporary atmospheric pollution control measures were terminated. | XIN JinYuan WANG YueSi TANG GuiQian WANG LiLi SUN Yang WANG YingHong HU Bo SONG Tao JI DongSheng WANG WeiFeng LI Liang LIU GuangRen | 2010 | Chinese Science Bulletin2010,55,18: | 30 |
| 4 | Isolation and Identification of Cancer Stem-Like Cells from Murine Melanoma Cell Lines显示文摘In current study,cancer stem-like cells in the murine melanoma B16F10 cells were investigated.CD phenotypes of the B16F10 cells were analyzed by flow cytometry,and the specific CD phenotype cells from the B16F10 cells were isolated by MACS.Then we used colony formation assay in soft agar media,the cell growth assay in serum-free culture media as well as the tumorigenicity investigation of the specific CD phenotype cells in C57BL/6 mice, respectively,to identify cancer stem-like cells in the B16F10 cells.The results showed that the B16F10 cells could form spherical clones in serum-free culture media,and the rate of clonegenesis of CD133 + ,CD44 + and CD44 + CD133 + cells was higher than that of CD133 - ,CD44 - and CD44 + CD133 - cells in soft agar media,respectively. The tumorigenic potential of CD133 + ,CD44 + ,CD44 + CD133 + cells and CD44 + CD133 + CD24 + cells was stronger than that of CD133 - ,CD44 - ,CD44 + CD133 - cells and CD44 + CD133 + CD24 - cells in mice,respectively.In conclusion,the CD44 + CD133 + CD24 + cells have some biological properties of cancer stem-like cells or are highly similar to the characteristics of cancer stem cells(CSC).These results provide an important method for identifying cancer stem-like cells in B16F10 cells and for further cancer target therapy. | Jun Dou Meng Pan Ping Wen Yating Li Quan Tang Lili Chu Fengshu Zhao Chuilian Jiang Weihua Hu Kai Hu Ning Gu | 2007 | Cellular & Molecular Immunology2007,4,6: | 25 |
| 5 | Effect of seawater on incident plane P and SV waves at ocean bottom and engineering characteristics of offshore ground motion records off the coast of southern California, USA显示文摘The effect of seawater on vertical ground motions is studied via a theoretical method and then actual offshore ground motion records are analyzed using a statistical method. A theoretical analysis of the effect of seawater on incident plane P and SV waves at ocean bottom indicate that on one hand, the affected frequency range of vertical ground motions is prominent due to P wave resonance in the water layer if the impedance ratio between the seawater and the underlying medium is large, but it is greatly suppressed if the impedance ratio is small; on the other hand, for the ocean bottom interface model selected herein, vertical ground motions consisting of mostly P waves are more easily affected by seawater than those dominated by SV waves. The statistical analysis of engineering parameters of offshore ground motion records indicate that:(1) Under the infl uence of softer surface soil at the seafl oor, both horizontal and vertical spectral accelerations of offshore motions are exaggerated at long period components, which leads to the peak spectral values moving to a longer period.(2) The spectral ratios(V/H) of offshore ground motions are much smaller than onshore ground motions near the P wave resonant frequencies in the water layer; and as the period becomes larger, the effect of seawater becomes smaller, which leads to a similar V/H at intermediate periods(near 2 s). These results are consistent with the conclusions of Boore and Smith(1999), but the V/H of offshore motion may be smaller than the onshore ground motions at longer periods(more than 5 s). | Diao Hongqi Hu Jinjun Xie Lili | 2014 | Earthquake Engineering and Engineering Vibration2014,13,2: | 24 |
| 6 | A Chromosome-Scale Genome Assembly of Paper Mulberry(Bmussonetia papyrifera)Provides New Insights into Its Forage and Papermaking Usage显示文摘Paper mulberry(Broussonetia papyrifera)is a well-known woody tree historically used for Cai Lun papermaking,one of the four great inventions of ancient China.More recently,Paper mulberry has also been used as forage to address the shortage of feedstuff because of its digestible crude fiber and high protein contents.In this study,we obtained a chromosome-scale genome assembly for Paper mulberry using integrated approaches,including Illumina and PacBio sequencing platform as well as Hi-C,optical,and genetic maps.The assembled Paper mulberry genome consists of 386.83 Mb,which is close to the estimated size,and 99.25%(383.93 Mb)of the assembly was assigned to 13 pseudochromosomes.Comparative genomic analysis revealed the expansion and contraction in the flavonoid and lignin biosynthetic gene families,respectively,accounting for the enhanced flavonoid and decreased lignin biosynthesis in Paper mulberry.Moreover,the increased ratio of syringyl-lignin to guaiacyl-lignin in Paper mulberry underscores its suitability for use in medicine,forage,papermaking,and barkcloth making.We also identified the rootassociated microbiota of Paper mulberry and found that Pseudomonas and Rhizobia were enriched in its roots and may provide the source of nitrogen for its stems and leaves via symbiotic nitrogen fixation.Collectively,these results suggest that Paper mulberry might have undergone adaptive evolution and recruited nitrogen-fixing microbes to promote growth by enhancing flavonoid production and altering lignin monomer composition.Our study provides significant insights into genetic basis of the usefulness of Paper mulberry in papermaking and barkcloth making,and as forage.These insights will facilitate further domestication and selection as well as industrial utilization of Paper mulberry worldwide. | Xianjun Peng Hui Liu Peilin Chen Feng Tang Yanmin Hu Fenfen Wang Zhi Pi Meiling Zhao Naizhi Chen Hui Chen Xiaokang Zhang Xueqing Yan Min Liu Xiaojun Fu Guofeng Zhao Pu Yao Lili Wang He Dai Xuming Li Wei Xiong Wencai Xu Hongkun Zheng Haiyan Yu Shihua Shen | 2019 | Molecular Plant2019,12,5: | 18 |
| 7 | Neuroprotective effect of ischemic preconditioning in focal cerebral infarction: relationship with upregulation of vascular endothelial growth factor显示文摘Neuroprotection by ischemic preconditioning has been confirmed by many studies, but the precise mechanism remains unclear. In the present study, we performed cerebral ischemic preconditioning in rats by simulating a transient ischemic attack twice(each a 20-minute occlusion of the middle cerebral artery) before inducing focal cerebral infarction(2 hour occlusion-reperfusion in the same artery). We also explored the mechanism underlying the neuroprotective effect of ischemic preconditioning. Seven days after occlusion-reperfusion, tetrazolium chloride staining and immunohistochemistry revealed that the infarct volume was significantly smaller in the group that underwent preconditioning than in the model group. Furthermore, vascular endothelial growth factor immunoreactivity was considerably greater in the hippocampal CA3 region of preconditioned rats than model rats. Our results suggest that the protective effects of ischemic preconditioning on focal cerebral infarction are associated with upregulation of vascular endothelial growth factor. | Yong Liu Suiqiang Zhu Yunfu Wang Jingquan Hu Lili Xu Li Ding Guangjian Liu | 2014 | Neural Regeneration Research2014,9,11: | 15 |
| 8 | Evolution of boundary layer ozone in Shijiazhuang,a suburban site on the North China Plain显示文摘The structure of the boundary layer affects the evolution of ozone(O3), and research into this structure will provide important insights for understanding photochemical pollution.In this study, we conducted a one-month observation(from June 15 to July 14, 2016) of the boundary layer meteorological factors as well as O3 and its precursors in Luancheng County,Shijiazhuang(37°53′N, 114°38′E). Our research showed that photochemical pollution in Shijiazhuang is serious, and the mean hourly maximum and mean 8-hr maximum O3 concentrations are 97.9 ± 26.1 and 84.4 ± 22.4 ppbV, respectively. Meteorological factors play a significant role in the formation of O3. High temperatures and southeasterly winds lead to elevated O3 values, and at moderate relative humidity(40%–50%) and medium boundary layer heights(1200–1500 m), O3 production sensitivity occurred in the transitional region between volatile organic compounds(VOC) and nitrogen oxides(NOx) limitations,and the O3 concentration was the highest. The vertical profiles of O3 were also measured by a tethered balloon. The results showed that a large amount of O3 was stored in the residual layer, and the concentration was positively correlated with the O3 concentration measured the previous day. During the daytime of the following day, the contribution of O3 stored in the residual layer to the boundary layer reached 27%± 7% on average. | Wei Zhao Guiqian Tang Huan Yu Yang Yang Yinghong Wang Lili Wang Junlin An Wenkang Gao Bo Hu Mengtian Cheng Xingqin An Xin Li Yuesi Wang | 2019 | Journal of Environmental Sciences2019,31,9: | 15 |
| 9 | Optimizing aerobic biodegradation of dichloromethane using response surface methodology显示文摘Response surface methodology(RSM) was employed to evaluate the optimum aerobic biodegradation of dichloromethane(DCM) in pure culture.The parameters investigated include the initial DCM concentration,glucose as an inducer and hydrogen peroxide as terminal electron acceptor(TEA) .Maximum aerobic biodegradation effciency was predicted to occur when the initial DCM concentration was 380 mg/L,glucose 13.72 mg/L,and H2O2 115 mg/L.Under these conditions the aerobic biodegradation rate reached up to 93.18%,which was significantly higher than that obtained under original conditions.Without addition of glucose,degradation effciencies were 80%at DCM concentrations<326 mg/L.When concentrations of DCM were more than 480 mg/L,the addition of hydrogen peroxide did not help to significantly increase DCM degradation effciency.When DCM concentrations increased from 240 to 480 mg/L,the overall DCM degradation effciency decreased from 91%to 60%in the presence of H2O2 for 120 mg/L. | WU Shijin,YU Xiang,HU Zhihang,ZHANG Lili,CHEN Jianmeng College of Biological and Environmental Engineering,Zhejiang University of Technology,Hangzhou 310032,China | 2009 | Journal of Environmental Sciences2009,21,9: | 13 |
| 10 | COVID-19: Challenges to GIS with Big Data显示文摘The outbreak of the 2019 novel coronavirus disease(COVID-19)has caused more than 100,000 people infected and thousands of deaths.Currently,the number of infections and deaths is still increasing rapidly.COVID-19 seriously threatens human health,production,life,social functioning and international relations.In the fight against COVID-19,Geographic Information Systems(GIS)and big data technologies have played an important role in many aspects,including the rapid aggregation of multi-source big data,rapid visualization of epidemic information,spatial tracking of confirmed cases,prediction of regional transmission,spatial segmentation of the epidemic risk and prevention level,balancing and management of the supply and demand of material resources,and socialemotional guidance and panic elimination,which provided solid spatial information support for decision-making,measures formulation,and effectiveness assessment of COVID-19 prevention and control.GIS has developed and matured relatively quickly and has a complete technological route for data preparation,platform construction,model construction,and map production.However,for the struggle against the widespread epidemic,the main challenge is finding strategies to adjust traditional technical methods and improve speed and accuracy of information provision for social management.At the data level,in the era of big data,data no longer come mainly from the government but are gathered from more diverse enterprises.As a result,the use of GIS faces difficulties in data acquisition and the integration of heterogeneous data,which requires governments,businesses,and academic institutions to jointly promote the formulation of relevant policies.At the technical level,spatial analysis methods for big data are in the ascendancy.Currently and for a long time in the future,the development of GIS should be strengthened to form a data-driven system for rapid knowledge acquisition,which signifies ts that GIS should be used to reinforce the social operation parameterization of models and methods,especially when providing support for social management. | Chenghu Zhou Fenzhen Su Tao Pei An Zhang Yunyan Du Bin Luo Zhidong Cao Juanle Wang Wen Yuan Yunqiang Zhu Ci Song Jie Chen Jun Xu Fujia Li Ting Ma Lili Jiang Fengqin Yan Jiawei Yi Yunfeng Hu Yilan Liao Han Xiao | 2020 | Geography and Sustainability2020,1,1: | 13 |
| 11 | Rice Expression Database(RED):An integrated RNA-Seq-derived gene expression database for rice显示文摘Rice is one of the most important stable food as well as a monocotyledonous model organism for the plant research community.Here,we present RED(Rice Expression Database;http://gffzzd1bc3ab4bbbc4005hqbxu5bpbk5xf600u.ffgz.tsg.suse.edu.cn),an integrated database of rice gene expression profiles derived entirely from RNA-Seq data.RED features a comprehensive collection of 284 high-quality RNA-Seq experiments,integrates a large number of gene expression profiles and covers a wide range of rice growth stages as well as various treatments.Based on massive expression profiles,RED provides a list of housekeeping and tissue-specific genes and dynamically constructs co-expression networks for gene(s) of interest.Besides,it provides user-friendly web interfaces for querying,browsing and visualizing expression profiles of concerned genes.Together,as a core resource in BIG Data Center,RED bears great utility for characterizing the function of rice genes and better understanding important biological processes and mechanisms underlying complex agronomic traits in rice. | Lin Xia Dong Zou Jian Sang Xingjian Xu Hongyan Yin Mengwei Li Shuangyang Wu Songnian Hu Lili Hao Zhang Zhang | 2017 | Journal of Genetics and Genomics2017,44,5: | 12 |
| 12 | Fine-Tuning of MiR528 Accumulation Modulates Flowering Time in Rice显示文摘In plants,microRNA (miRNA) functions in the post-transcriptional repression of target mRNAs have been well explored.However,the mechanisms regulating the accumulation of miRNAs remain poorly under.stood.Here,we report that distinct mechanisms regulate accumulation of a monocot-specific miRNA,rice (Oryza sativa) miR528.At the transcriptional level,miR528 accumulated to higher levels in older plants than in young seedlings and exhibited aging-modulated gradual accumulation and diurnal rhythms in leaves;at the post-transcriptional level,aging also modulated miR528 levels by enhancing pri-miR528 alter.native splicing.We found that miR528 promotes rice flowering under long-day conditions by targeting RED AND FAR-RED INSENSITIVE2 (OsRFI2).Moreover,natural variations in the MIR528 promoter region caused differences in miR528 expression among rice varieties,which are correlated with their different binding affinities with the transcription factor OsSPL9 that activates the expression of miR528.Taken together,our findings reveal rice plants have evolved sophisticated modes fine-tuning miR528 levels and provide insight into the mechanisms that regulate MIRNA expression in plants. | Rongxin Yang Pingchuan Li Hailiang Mei Dong Wang Jing Sun Chao Yang Lili Hao Shouyun Cao Chengcai Chu Songnian Hu Xianwei Song Xiaofeng Cao | 2019 | Molecular Plant2019,12,8: | 12 |
| 13 | Overexpressed miR-9 promotes tumor metastasis via targeting E-cadherin in serous ovarian cancer显示文摘MicroRNAs (miRNAs ) 玩在在各种各样的癌症的发展和前进的关键角色。不正常的 miR-9 表示仍然保持模糊,并且卵巢的癌症的变形前进上的一致都没被到达。在这研究,从生物信息学分析的结果证明 E-cadherin mRNA 的 3-UTR 被 miR-9 直接调整。酶记者试金结果证实 miR-9 能直接指向这 3-UTR。在卵巢的癌症织物的 miR-9 和 E-cadherin 表示被 qRT-PCR 确定。移植和侵略被在 SKOV3 和 A2780 愈合弯屈和 Transwell 系统试金检测。qRT-PCR 和西方的污点被执行检测上皮 ? 间充质的联系转变的 mRNA 和蛋白质。Immunofluorescence 技术被用来分析表示和 E-cadherin, N-cadherin,和 vimentin 的 subcellular 本地化。结果证明 miR-9 经常与配对的主要的相比是在变形浆液的卵巢的癌症织物的 upregulated。miR-9 的 Upregulation 能 downregulate E-cadherin 的表示但是 upregulate 间充质的标记(N-cadherin 和 vimentin ) 的表示。miR-9 的 Overexpression 能在卵巢的癌症支持房间移植和侵略,并且这些进程能有效地经由 miR-9 禁止者被禁止。因此,我们的学习证明 miR-9 可以经由指向 E-cadherin 和一条新奇潜在的治疗学的途径控制卵巢的癌症的转移支持卵巢的癌症转移。 | Bo Zhou Hongbin Xu Meng Xia Chaoyang Sun Na Li Ensong Guo Lili Guo Wanying Shan Hao Lu Yifan Wu Yuan Li Degui Yang Danhui Weng Li Meng Junbo Hu Ding Ma Gang Chen Kezhen Li | 2017 | Frontiers of Medicine2017,11,2: | 10 |
| 14 | Multiple transgenes Populus xeuramericana 'Guariento' plants obtained by biolistic bombardment显示文摘A JERF36 regulation gene, a selection marker gene (NPT-II), and the foreign genes levansucrase (SacB), Vitreoscilla hemoglobin (vgb), and Binary coleopterus insect resistance (BtCry3A+OC-I) were co-transferred into Populus xeuramericana 'Guariento' using biolistic bombardment; 25 kanamycin resistant plants were obtained. The results of PCR and Southern hybridization showed that the foreign genes had been integrated into the genome of P. xeuramericana 'Guariento' and 5 genes were all transferred into 7 poplar plants. The results of a BtCry3A ELISA experiment indicated that the BtCry3A gene was expressed in the 7 transgenic poplar plants, and these plants grew well on coastal saline land. | Wang JianGe Su XiaoHua Ji LiLi Zhang BingYu Hu ZanMin Huang RongFeng Tian YingChuan | 2007 | Chinese Science Bulletin2007,52,2: | 10 |
| 15 | Long Non-coding RNAs and Their Biological Roles in Plants显示文摘With the development of genomics and bioinformatics, especially the extensive applications of high-throughput sequencing technology, more transcriptional units with little or no protein-coding potential have been discovered. Such RNA molecules are called nonprotein-coding RNAs(npc RNAs or nc RNAs). Among them, long npc RNAs or nc RNAs(lnpc RNAs or lnc RNAs) represent diverse classes of transcripts longer than 200 nucleotides. In recent years, the lnc RNAs have been considered as important regulators in many essential biological processes. In plants, although a large number of lnc RNA transcripts have been predicted and identified in few species, our current knowledge of their biological functions is still limited.Here, we have summarized recent studies on their identification, characteristics, classification,bioinformatics, resources, and current exploration of their biological functions in plants. | Xue Liu Lili Hao Dayong Li Lihuang Zhu Songnian Hu | 2015 | Genomics, Proteomics & Bioinformatics2015,13,3: | 9 |
| 16 | Synergistic immunoreaction of acupuncture-like dissolving microneedles containing thymopentin at acupoints in immune-suppressed rats显示文摘Dissolving microneedles carried drug molecules can effectively penetrate the stratum corneum of skin to improve the transdermal drug delivery. The traditional Chinese medicine acupuncture is based on the needle stimulation at a specific location(acupoint) to generate and transmit biochemical and physiological signals which alter the pathophysiological state of patients. However, the pain associated with conventional acupuncture needles and the requirement of highly trained professionals limit the development of acupuncture in non-Asian countries. The purpose of this study is to investigate whether the dissolving microneedles can be utilized as a self-administered painless replacement for acupuncture and locally released drug molecules can achieve expected therapeutic outcomes. Immunosuppressive rats were treated with acupuncture at Zusanli(ST36) acupoint using microneedles containing thymopentin.The immune functions and psychological mood of the immunosuppressed animals were examined. The proliferation of splenocytes was examined by CCK-8 assay. CD4 and CD8 expression patterns in spleen cells were detected by flow cytometry. The current study showed that use of either microneedles containing thymopentin or conventional acupuncture both resulted in immune cell proliferation, which was confirmed by flow cytometry. Furthermore, either conventional acupuncture or microneedles were able to effectively mitigate the anxiety caused by immune-suppression when applied on the ST36. | Qian Zhang Chuncao Xu Shiqi Lin Huanbin Zhou Gangtao Yao Hu Liu Lili Wang Xin Pan Guilan Quan Chuanbin Wu | 2018 | Acta Pharmaceutica Sinica B2018,8,3: | 9 |
| 17 | Branched glycerol dialkyl glycerol tetraethers and paleoenvironmental reconstruction in Zoigê peat sediments during the last 150 years显示文摘Branched glycerol dialkyl glycerol tetraethers (GDGTs) were analyzed in peat samples taken from the Zoigê grassland, located on the eastern margin of the Qinghai-Tibetan Plateau. The mean annual air temperature (MAAT) and pH in the 210 Pb-dating peat core were reconstructed based on the cyclization of branched tetraethers (CBT) and methylation of branched tetraethers (MBT) indices for the last 150 years. The results showed that the MAAT and pH values involved three stages of variation over the last 150 years. The pH was stable and the MAAT decreased slowly by about 1°C from 1851 to 1927. The pH decreased rapidly by 0.6 and the MAAT decreased significantly by 2.5°C between 1927 and 1979. The pH and MAAT increased by 0.8 and 5°C, respectively, since the 1980s. The reconstructed temperatures correspond well to the mean winter temperatures reconstructed using tree-rings from the Jiuzhaigou Valley, situated at the boundary between the Qinghai-Tibetan Plateau and the Sichuan Basin. The estimated MAAT was similar to the temperatures reconstructed using tree-rings, indicating an increasing trend, as shown by local instrumental records from 1957 to 2001. These results provide further confidence in the application of proxies based on glycerol dialkyl glycerol tetraethers in peat records for continental paleoclimate reconstruction. | ZHOU HaoDa HU JianFang MING LiLi PENG PingAn ZHANG Gan | 2011 | Chinese Science Bulletin2011,56,23: | 9 |
| 18 | DEVELOPMENT OF EXPERIMENTAL METHODS FOR IMPACT TESTING BY COMBINING HOPKINSON PRESSURE BAR WITH OTHER TECHNIQUES显示文摘The split Hopkinson pressure bar(SHPB) technique and the wave propagation inverse analysis(WPIA) technique are both extensively used to experimentally investigate the impact behavior of materials, although neither of them alone provides a fully satisfactory analysis. In the present paper, attention is given to new experimental techniques by incorporating a damagemodified constitutive model into the SHPB technique and combining the Hopkinson pressure bar(HPB) technique with WPIA. First, to distinguish the response due to dynamic constitutive behavior and the response due to dynamic damage evolution, the SHPB method incorporating a damage-modified constitutive model is developed, including an explicit damage-modified Zhu–Wang–Tang model and an implicit damage-modified constitutive model. Second, when the SHPB results become invalid, a method of combining new Lagrange inverse analyses with the HPB technique is developed, including cases of the HPB arranged in front of a long specimen and behind the specimen. As examples of these new methods, typical results are given for nonlinear viscoelastic polymers and concretes considering damage evolution, a super-elastic Ti–Ni alloy with phase transformation and an aluminum foam with shock waves propagating within it. | Lili Wang Shisheng Hu Liming Yang Zijian Sun Jue Zhu Huawei Lai Yuanyuan Ding | 2014 | Acta Mechanica Solida Sinica2014,27,4: | 9 |
| 19 | Spatial distribution of heavy metals(Cu, Pb, Zn, and Cd)in sediments of a coastal wetlands in eastern Fujian, China显示文摘We investigated the spatial distribution(horizontal and vertical concentrations) of copper(Cu),lead(Pb), zinc(Zn), and cadmium(Cd) in five wetland types(mudflat, aquaculture wetland, water area, farmland wetland and mangrove) from three areas(Ningde, Fuding,and Xiapu), China. Cu concentrations in five wetland types descended in the order: farm wetland, mudflat, aquaculture,water area and mangrove. Pb concentrations decreased in the order: aquaculture, mangrove, farm wetland, mudflat,and water area. Zn content decreased in the order: farm wetland, water area, aquaculture, mudflat and mangrove,and Cd content decreased as follows: mangrove, aquaculture, water area, mudflat, and farm wetland. Comparison of the concentrations of the same heavy metals in different areas showed that the highest Cu(63.75 mg kg^-1) and Zn(152.32 mg kg^-1) concentrations occurred in Ningde coastal wetlands; Pb(110.58 mg kg^-1) and Cd(2.81 mg kg^-1) contents were highest in Fuding wetlands,and the average contents of all heavy metals were very low in Xiapu wetlands. Examination of the vertical distribution showed that the Cu content was high in all mudflat layers;Pb and Cd concentrations were highest in aquaculture and mangrove wetlands, respectively, and Zn content was highest in farm wetlands. The spatial distribution of Cu and Zn contents for different areas decreased as follows:Ningde [ Fuding [ Xiapu, for Pb and Cd were most concentrated in Fuding coastal wetlands. Concentrations of Zn and Cu were highly correlated, while Zn and Cu were not significantly correlated with Pb. | Lili Zhao Weibin You Haiqing Hu Wei Hong Xiaojuan LIAO Shihong Xiao Ren Wang Jinbiao Cai Xuncheng Fan Yong Tan Dongjin He | 2015 | Journal of Forestry Research2015,26,3: | 8 |
| 20 | Large aperture N31 neodymium phosphate laser glass for use in a high power laser facility显示文摘Large aperture Nd:phosphate laser glass is a key optical element for an inertial confinement fusion(ICF) facility. N31,one type of neodymium doped phosphate glasses, was developed for high peak power laser facility applications in China. The composition and main properties of N31 glass are given, together with those of LHG-8, LG-770, and KGSS-0180 Nd:phosphate laser glasses, from Hoya and Schott, and from Russia. The technologies of pot melting, continuous melting, and edge cladding of large size N31 phosphate laser glass are briefly described. The small signal gain profiles of N31 glass slabs from both pot melting and continuous melting at various values of the pumping energy of the xenon lamp are presented. N31 glass is characterized by a stimulated emission cross section of 3.8 × 10-20cm2 at 1053 nm,an absorption coefficient of 0.10–0.15% cm-1at laser wavelength, small residual stress around the interface between the cladding glass and the laser glass, optical homogeneity of ~2 × 10-6in a 400 mm aperture, and laser damage threshold larger than 42 J/cm2 for a 3 ns pulse width at 1064 nm wavelength. | Lili Hu Shubin Chen Jingping Tang Biao Wang Tao Meng Wei Chen Lei Wen Junjiang Hu Shunguang Li Yongchun Xu Yasi Jiang Junzhou Zhang Zhonghong Jiang | 2014 | High Power Laser Science and Engineering2014,2,1: | 8 |