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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 | Pathogenic T-cells and inflammatory monocytes incite inflammatory storms in severe COVID-19 patients显示文摘Pathogenic human coronavirus infections,such as severe acute respiratory syndrome CoV(SARS-CoV)and Middle East respiratory syndrome CoV(MERS-CoV),cause high morbidity and mortality[1,2].Recently,a severe pneumonia-associated respiratory syndrome caused by a new coronavirus(SARS-CoV-2)was reported in December 2019 in the city of Wuhan,Hubei province,China[3-5],which was also named as pneumonia-associated respiratory syndrome(PARS)[6]and can cause coronavirus disease 2019(COVID-19)to seriously endanger human health. | Yonggang Zhou Binqing Fu Xiaohu Zheng Dongsheng Wang Changcheng Zhao Yingjie Qi Rui Sun Zhigang Tian Xiaoling Xu Haiming Wei | 2020 | National Science Review2020,7,6: | 54 |
| 3 | Correlation of E-selectin gene polymorphisms with risk of ischemic stroke A meta-analysis显示文摘OBJECTIVE: To investigate the association of E-selectin S128R polymorphisms with ischemic stroke. DATA SOURCES: A computer-based online search was conducted in PubMed, Elsevier, Ovid Database, the China National Knowledge Infrastructure, and Wanfang Database between January 1998 and December 2010. STUDY SELECTION: Case-controlled studies addressing the association of the E-selectin polymorphism and ischemic stroke were included in this review. The genotype distribution complied with the Hardy-Weinberg genetic equilibrium. The included reports were evaluated by two authors for strict quality screening. Meta-analysis software, REVMAN 5.1, was used to investigate heterogeneity, pooled odds ratio (OR) and 95% confidence interval (CI) in individual studies. MAIN OUTCOME MEASURES: Genotype and allele distributions at the E-selectin S128R site. RESULTS: Six case-controlled studies were included after screening and application of inclusion and exclusion criteria. There was no heterogeneity in the genotype and allele frequencies, and no publication bias was found. Meta-analysis of the pooled data showed that the OR value of the (AC+CC)/AA genotype was 1.93 (95% CI: 1.55-2.41, Z = 5.80, P < 0.000 01), and the OR for the C/A allele was 1.80 (95% CI: 1.47-2.22, Z = 5.59, P < 0.000 01) in the ischemic stroke group, compared with control group. Results of pooled data in Chinese subjects showed that the OR value of (AC+CC)/AA was 2.36 (95% CI: 1.68-3.31, Z = 4.99, P < 0.000 01), and the OR value of the C/A allele was 2.25 (95% CI: 1.63-3.12, Z = 4.89, P < 0.000 01). CONCLUSION: Polymorphism of E-selectin S128R was significantly associated with susceptibility to ischemic stroke; the AC and CC genotypes as well as the C allele may be factors associated with susceptibility to ischemic stroke. | Qingli Sun Yu Fu Aping Sun Yanhong Shou Mei Zheng Xiaogang Li Dongsheng Fan | 2011 | Neural Regeneration Research2011,6,22: | 46 |
| 4 | In vitro derivation of functional insulin-producing cells from human embryonic stem cells显示文摘为人的胚胎的茎(ES ) 的自强和区别的能力细胞为对待类型 Idiabetes mellitus 为胰腺的贝它细胞的产生使他们成为潜在的来源。这里,我们报导一最新发展了并且有效方法,在aserum免费的系统执行了,区分进生产胰岛素的 cells.Activin A 的导致的人的 ES 房间它在起始的阶段被使用从人的 EScells 导致权威的内胚叶区别,是由权威的内胚叶标记 Sox17 和 Brachyury.Further 的表示检测了, all-trans retinoic 酸( RA )被用来支持胰腺的区别,由早胰腺的抄写因素 pdx1 和 hlxb9 的表示显示了。在成熟 inDMEM/F12 以后有 bFGF 和菸碱的没有浆液的媒介,区分的房间表示了小岛特定的标记象 C 肽,胰岛素,胰高血糖素和 glut2 那样。百分比 ofC-peptide-positive 房间超过了 15% 。由这些房间的胰岛素和 C 肽的分泌物在葡萄糖层次对应于变化。当移植了进肾的囊时, ofStreptozotocin (STZ ) 对待裸体老鼠,这些区分的人的 ES 房间熬过并且维持贝它房间标记基因的表示包括 C 肽, pdx1, glucokinase, nkx6.1, IAPP, pax6and Tcf1。百分之三十只移植裸体老鼠展出了 stableeuglycemia 的明显的恢复;并且改正的显型被支撑超过六个星期。我们的新方法为学习人的胰开发的机制提供一个有希望的试管内区别模特儿并且说明为类型 Idiabetes mellitus 的处理使用人的 ES 房间的潜力。 | Wei Jiang Yan Shi Dongxin Zhao Song Chen Jun Yong Jing Zhang Tingting Qing Xiaoning Sun Peng Zhang Mingxiao Ding Dongsheng Li Hongkui Deng | 2007 | Cell Research2007,17,4: | 38 |
| 5 | 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 |
| 6 | Characterization of volatile organic compounds in the urban area of Beijing from 2000 to 2007显示文摘Beijing is one of the most polluted cities in the world.In this study,the long-term and continuous measurements of volatile organic compounds (VOCs) in the urban area of Beijing,specifically at Beijing 325 m Meteorological Tower,were conducted from 2000 to 2007.The annual record of VOC trends exhibited in two different phases was separated in 2003.Records show that VOC concentrations increased from 2000 to 2003 due to the abrupt increase in vehicle number.Contrarily,since 2003,there had been a decrease in VOCs concentrations as the policy on gasoline and air pollution was implemented.Toluene,benzene,and i-pentane are the chemicals that abound in and are directly related to vehicle activity,such as in vehicle exhaust and gasoline evaporation.Furthermore,records indicate that there had been seasonal variation in VOCs levels in that VOCs level in summer is higher than that in winter.As such,temperature is considered to significantly contribute to VOCs in Beijing.Records also show that VOCs level was high in the morning and during rush hours in the evening.In contrast,VOCs level was low during midday due to photochemical destruction with OH radical and dilution effect.In this study,a particular benzene to toluene ratio range (0.4-1.0) was used as the indicator of air propelled by vehicular exhaust.We also applied the correlation coefficients between BTEX and i-pentane to evaluate evaporation influence to ambient BTEX in the Beijing urban area. | Yuesi Wang Xiyan Ren Dongsheng Ji Junqang Zhang Jie Sun Fankun Wu | 2012 | Journal of Environmental Sciences2012,24,1: | 21 |
| 7 | Dynamic recrystallization behavior of GH4169G alloy during hot compressive deformation显示文摘The microstructure evolutions and nucleation mechanisms of GH4169G alloy were studied by optical microscope, electron backscatter diffraction (EBSD) and transmission electron microscope (TEM). The hot compression tests were performed different imposed reductions in the range of true strain from 0.12 to 1.2 at the temperatures of 930 °-1050 ° with strain rates of 0.01 s^-1-l s^-1. It is found that cumulative and local misorientation increase firstly and then decrease when the strain is increased due to the progress of dynamic recrystallization (DRX). The low angle boundaries (LAGBs) rapidly develop to high angle boundaries (HAGBs) at relatively high deformation temperature or the low strain rate. There are three DRX mechanisms observed for GH4169 G alloy during hot deformation. Discontinuous dynamic recrystallization (DDRX) as the dominant mechanism for GH4169 G alloy is characterized by typical necklace structures and bulged-original boundaries. Besides, different deformation bands with dislocation cells formed in deformed matrix at low temperature and large strain, which indicates that continuous dynamic recrystallization (CDRX) contributed to the DRX process. The twin boundaries lost their coherent characteristics and provide sites for nucleation, which also accelerates the nucleation of DRX. | Dan Jia Wenru Sun Dongsheng Xu Fang Liu | 2019 | Journal of Materials Science & Technology2019,35,9: | 13 |
| 8 | Stepwise advance of the Mu Us Desert since late Pliocene:Evidence from a red clay-loess record显示文摘Analyses of paleomagnetic polarity reversals, magnetic susceptibility and grain size on the red clay-loess sequence, about 280 m thick, at Jingbian show that this sequence contains most of the stratigraphic units recorded in the standard red clay-loess sections of the Loess Plateau over the past 3.5 Ma. Using sand particle percentage ( > 63 μm%) of the eolian sequence as a proxy indicator of desert extent and aridity in the dust source regions, it is found that during the past 3.5 Ma, there are three important climatic events indicating the advance of the Mu Us Desert. The events occurred at about 2.6, 1.1 and 0.6 MaBP, respectively. The stepwise advance of the Mu Us Desert may be linked closely to increase in global ice volume and uplift of the Tibetan Plateau in the late Cenozoic. | Zhongli Ding Jimin Sun Dongsheng Liu | 1999 | Chinese Science Bulletin1999,44,13: | 12 |
| 9 | The influence of particle size and concentration combined with pH on coagulation mechanisms显示文摘In order to evaluate the influence of particle size and particle concentration on the coagulation process, two kinds of particle suspensions, nanoparticles and microparticles,were employed to investigate the effect of particle size on coagulation mechanisms with varying coagulation parameters. Results showed that it is easier for nanoparticles to cause self-aggregation because of Brownian motion, while interception and sedimentation are the mainly physical processes affecting particle transport for microparticles, so they are more stable and disperse more easily. The particle size distribution and particle concentration had distinct influence on the coagulation mechanisms. Under neutral conditions, as the amount of coagulant increased, the coagulation mechanism for nanoparticles changed from charge neutralization to sweep flocculation and the nanoparticles became destabilized, re-stabilized and again destabilized. For microparticles, although the coagulation mechanism was the same as that of nanoparticles, the increased rate of aluminum hydroxide precipitation exceeded the adsorption of incipiently formed soluble alum species, resulting in the disappearance of the re-stabilization zone. Under acidic conditions, Brownian motion dominates for nanoparticles at low particle concentrations, while sweep flocculation is predominant at high particle concentrations. As for microparticles, charge neutralization and sweep flocculation are the mechanisms for low and high particle concentrations respectively.Under alkaline condition, although the mechanisms for both nano-and microparticles are the same, the morphology of flocs and the kinetics of floc formation are different. At low particle concentrations, nanoparticles have larger growth rate and final size of flocs, while at high particle concentrations, nanoparticles have higher fractal dimension and recovery factors. | Hongyan Sun Ruyuan Jiao Hui Xu Guangyu An Dongsheng Wang | 2019 | Journal of Environmental Sciences2019,31,8: | 12 |
| 10 | Porosity and permeability evolution and evaluation in anisotropic porosity multiscale-multiphase-multicomponent structure显示文摘Based on the hybrid hypersingular integral equation-lattice Boltzmann methods (HHIE-LBM), the porosity and permeability evolution and evaluation process in anisotropic saturated porosity multiscale-multiphase-multicomponent (ASP-MS-MP-MC) structures under ultra high temperature and pressure conditions was analyzed on parallel CPU and GPU platforms. First, virtual physical models at multi-spatial scales (2 μm, 5 μm and 10 μm) were restructured by computerized microtomography technology and data. Second, using HHIE-LBM methods, the anisotropic porosity and permeability tensor at core level and pore level under ultra high temperature and pressure conditions were calculated. Third, the evolution and evaluation process of the porosity and permeability as a function of multi temporal spatial scales was investigated. Finally, the relationship between porosity and permeability and ASP-MS-MP-MC structures (micro-meso-macro-scale) was explored. | ZHU BoJing CHENG HuiHong QIAO YanChao LIU Chang SHI YaoLin ZHANG Kai SUN DongSheng LIN WeiRen | 2012 | Chinese Science Bulletin2012,57,4: | 11 |
| 11 | Three-dimensional in situ stress determination by anelastic strain recovery and its application at the Wenchuan Earthquake Fault Scientific Drilling Hole-1(WFSD-1)显示文摘In situ stress state becomes more and more significant with in-depth research on geodynamics and energy development.However,there has not been an economic and effective method developed to determine deep three-dimensional in situ stress.The Anelastic Strain Recovery(ASR)method is a newly developed technique that can determine three-dimensional in situ stresses.After the 12 May 2008 Ms8.0 Wenchuan earthquake,the ASR method was used for the first time in China's Mainland to measure the in situ stresses in the WFSD scientific boreholes in Sichuan Province,China.In this paper,the basic procedure of the ASR method is introduced in detail and the compliances of ASR for boring cores are investigated.The results show that the maximum principal stress direction was NW64°at a measured depth(MD)of 1173 m(vertical depth 1151 m)in WFSD-1.The ratio of shear mode to the volume mode compliance of ASR was 2.9.And the three principal stresses at 1173 m MD in WFSD-1are 43,28 and 25 MPa.Combined with stress measurement results determined using other in situ measurement methods along the Longmenshan fault zone,the directions of the maximum horizontal principal stress changes from E-W to NEE-SWW to NWW-SEE when moving from NE to SW along the Longmenshan fault zone.This change is in agreement with the stress regime of the Longmenshan fault zone of the Wenchuan Earthquake,which supports a stress regime consisting predominantly of thrusts in the southwest and strike-slip in the northeast. | SUN DongSheng LIN WeiRen CUI JunWen WANG HongCai CHEN QunCe MA YinSheng WANG LianJie | 2014 | Science China Earth Sciences2014,57,6: | 10 |
| 12 | Analysis of the Wenchuan Ms8.0 Earthquake's Co-seismic Stress and Displacement Change by Using the Finite Element Method显示文摘The variation of in situ stress before and after earthquakes is an issue studied by geologists. In this paper, on the basis of the fault slip dislocation model of Wenchuan Ms8.0 earthquake, the changes of co-seismic displacement and the distribution functions of stress tensor around the Longmen Shan fault zone are calculated. The results show that the co-seismic maximum surface displacement is 4.9 m in the horizontal direction and 6.5 m in the vertical direction, which is almost consistent with the on-site survey and GPS observations. The co-seismic maximum horizontal stress in the hanging wall and footwall decreased sharply as the distance from the Longmen Shan fault zone increased. However, the vertical stress and minimum horizontal stress increased in the footwall and in some areas of the hanging wall. The study of the co-seismic displacement and stress was mainly focused on the long and narrow region along the Longmen Shan fault zone, which coincides with the distribution of the earthquake aftershocks. Therefore, the co-seismic stress only affects the aftershocks, and does not affect distant faults and seismic activities. The results are almost consistent with in situ stress measurements at the two sites before and after Wenchuan Ms8.0 earthquake. Along the fault plane, the co-seismic shear stress in the dip direction is larger than that in the strike direction, which indicates that the faulting mechanism of the Longmen Shan fault zone is a dominant thrust with minor strike-slipping. The results can be used as a reference value for future studies of earthquake mechanisms. | SUN Dongsheng WANG Lianjie WANG Hongcai MA Yinsheng ZHOU Chunjing CUI Junwen | 2013 | Acta Geologica Sinica(English Edition)2013,87,4: | 9 |
| 13 | Emission Trading Based Optimal Scheduling Strategy of Energy Hub with Energy Storage and Integrated Electric Vehicles显示文摘This paper focuses on the optimal scheduling of the district energy system with multiple energy supply modes and flexible loads.For multi-energy system(MES),the energy hub(EH)model including energy storage system and integrated electric vehicle(EV)is established.Based on the model,the influence of pollutant trading market on total operation cost is analyzed,and the optimal scheduling strategy is further put forward to realize the minimum purchase cost and emission tax cost of the MES.Finally,this paper compares the economic benefit of the fixed mode and the response mode,and discusses the contribution of the energy storage device and the multi-energy complementary mode to energy utilization efficiency.The simulation results indicate that optimal scheduling strategy of the EH can coordinate various energy complementary modes reasonably.Meanwhile,the proposed strategy is able to improve the operation economy of the EH,and ensure the better response effect of the demand side.The sensitivity analysis demonstrates the impact of pollutant emission price change on emission reduction. | Yanhong Luo Xinwen Zhang Dongsheng Yang Qiuye Sun | 2020 | Journal of Modern Power Systems and Clean Energy2020,8,2: | 8 |
| 14 | Impending HRT wave precursors to the Wenchuan M_s8.0 earthquake and methods of earthquake impending prediction by using HRT wave显示文摘We deployed four geo-electric monitoring stations in Sichuan and Yunnan provinces from 2004, using the new generation of equipment (PS-100) and technologies to capture the HRT wave earthquake precursor. Before the Wenchuan Ms8.0 earthquake, we recorded the HRT wave precursor at the only operating station in Hongge (HG, Δ=465 km) and found that significant impending signal had been recorded at the station in the early morning ( 0―5 am) of 12th of May, 2008. The precursor for this earthquake is consistent with precursors recorded for other strong earthquakes. The measured physical properties (geo-resistivity and telluric-current) show tidal wave period oscillations from several days to several months before the earthquakes and the amplitude of such HT oscillation increases significantly towards the occurrence of an earthquake. These HT and RT waves from the epicenter have a causal relationship with the earthquakes that happened several days later. The arrival time of two RT waves is proportional to the distance from the station to the epicenter. The estimated natural decay of the amplitude is correlated with the natural period (T0) of the earthquake fault, which is proportional to the fault length. From this relationship, we can predict the earthquake magnitude. For magnitude 6―9 earthquakes, the natural period is about 1―6 hours. Such oscillation comes from the epicenter area and they can propagate several thousand kilometers in the Earth's crust. Before a strong earthquake in the shallow crust, the conductive pore fluid will experience major changes before the fault rapture. Such fluid change will emit an oscillation in the pore fluid pressure. This is the mechanism for the HRT wave generation. Since the China Earthquake Administration funded the HRT wave short-term earth-quake prediction project in 2003, the first record of HRT precursor wave has been recorded from the 2004-12-26 Sumatra Mw9.0 earthquake with the largest epicentre distance Δ=2900 km. Thereafter, we have captured HRT waves from more than twenty strong earthquakes, which are well-matched and show repeatability, consistency and regularity. All our observation with the HRT waves demonstrate that HRT wave precursors to earthquakes indeed exist. Strong earthquakes can be predicted and short-term and impending earthquake prediction is achievable in the very near future. From all the observations, including the ones at HG station from Wenchuan Ms8.0 earthquake, we conclude that using HRT wave to predict earthquakes is feasible. | QIAN FuYe ZHAO BiRu QIAN Wei ZHAO Jian HE ShiGen ZHANG HongKui LI ShiYu LI ShaoKun YAN GuLiang WANG ChengMin SUN ZhenKai ZHANG DongNing LU Jun ZHANG Ping YANG GuoJun SUN JiaLin GUO ChunSheng TANG YuXiong XU JianMing XIA KunTao JU Hang YIN BangHong LI Ming YANG DongSheng QI WeiLuo HE TaiMing GUAN HuaPing ZHAO YuLin | 2009 | Science China Earth Sciences2009,52,10: | 8 |
| 15 | Rapid repair techniques for severely earthquake-damaged circular bridge piers with flexural failure mode显示文摘In this study, three rapid repair techniques are proposed to retrofit circular bridge piers that are severely damaged by the flexural failure mode in major earthquakes. The quasi-static tests on three 1:2.5 scaled circular pier specimens are conducted to evaluate the efficiency of the proposed repair techniques. For the purpose of rapid repair, the repair procedure for all the specimens is conducted within four days, and the behavior of the repaired specimens is evaluated and compared with the original ones. A finite element model is developed to predict the cyclic behavior of the repaired specimens and the numerical results are compared with the test data. It is found that all the repaired specimens exhibit similar or larger lateral strength and deformation capacity than the original ones. The initial lateral stiffness of all the repaired specimens is lower than that of the original ones, while they show a higher lateral stiffness at the later stage of the test. No noticeable difference is observed for the energy dissipation capacity between the original and repaired pier specimens. It is suggested that the repair technique using the early-strength concrete jacket confined by carbon fiber reinforced polymer(CFRP) sheets can be an optimal method for the rapid repair of severely earthquake-damaged circular bridge piers with flexural failure mode. | Sun Zhiguo Li Hongnan Bi Kaiming Si Bingjun Wang Dongsheng | 2017 | Earthquake Engineering and Engineering Vibration2017,16,2: | 8 |
| 16 | Application of flow driven pore-network crack model to Zipingpu reservoir and Longmenshan slip显示文摘The study has analyzed the relationship between the water-drainage sluice process of reservoir, stress triggers and shadows of earthquake and porosity variability of fault slip zone. First, the pore pressure, pressure gradient, viscous stress and Reynolds stress to reservoir-earthquake fault slip problem are analyzed, and these are un-negligible factors of the extended coulomb failure stress under ultra-high temperature and pressure condition. Second, the porosity tensor and permeability tensor are studied, the relationship between Zipingpu reservoir and Longmenshan slip has been analyzed, and the extended viscous stress and Reynolds stress as function of time and infiltration process are obtained. Last, some primary conclusions about the flow-solid coupled facture mechanism to the Zipingpu reservoir and Longmenshan slip problem are presented, which can help understand the flow-solid coupled facture mechanism of reservoir-coseismic fault slip problem. | ZHU BoJing LIU Chang SHI YaoLin SUN DongSheng ZHANG Kai | 2011 | Science China(Physics,Mechanics & Astronomy)2011,54,8: | 8 |
| 17 | Cap-specific, terminal N^6-methylation by a mammalian m6Am methyltransferase显示文摘Dear Editor,Dynamic and reversible N6-methyladenosine (m6A) RNA methylation has been found to greatly impact gene expression, leading to the field of epitranscriptomics.1 Unlike m6A that is an internal modification, a terminal modification at mRNA cap in higher eukaryotes exists, termed as N6,2′-O-dimethyladenosine (m6Am) (Fig. 1a). | Hanxiao Sun Meiling Zhang Kai Li Dongsheng Bai Chengqi Yi | 2019 | Cell Research2019,29,1: | 7 |
| 18 | Rapid repair of severely earthquake-damaged bridge piers with flexural-shear failure mode显示文摘An experimental study was conducted to investigate the feasibility of a proposed rapid repair technique for severely earthquake-damaged bridge piers with flexural-shear failure mode. Six circular pier specimens were first tested to severe damage in flexural-shear mode and repaired using early-strength concrete with high-fluidity and carbon fiber reinforced polymers (CFRP). After about four days, the repaired specimens were tested to failure again. The seismic behavior of the repaired specimens was evaluated and compared to the original specimens. Test results indicate that the proposed repair technique is highly effective. Both shear strength and lateral displacement of the repaired piers increased when compared to the original specimens, and the failure mechanism of the piers shifted from flexural-shear failure to ductile flexural failure. Finally, a simple design model based on the Seible formulation for post-earthquake repair design was compared to the experimental results. It is concluded that the design equation for bridge pier strengthening before an earthquake could be applicable to seismic repairs after an earthquake if the shear strength contribution of the spiral bars in the repaired piers is disregarded and 1.5 times more FRP sheets is provided. | Sun Zhiguo Wang Dongsheng Du Xiuli Si Bingjun | 2011 | Earthquake Engineering and Engineering Vibration2011,10,4: | 7 |
| 19 | ^(14)C measurement of forest soils in Dinghushan Biosphere Reserve显示文摘Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14C values of these profiles decrease with increasing of depth. The Δ14C values in 30—40 cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 560 years ago. The 14C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 425 a BP, which is consistent with historical documents. The penetrating depths of 'bomb 14C' in Qingyunsi and Wukesong profiles are 10 and 20 cm, respectively. | SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi Guangzhou Institute of Geochemisry, Chinese Academy of Sciences, Guangzhou 510640, China Institute of Geology, Chinese Academy of Sciences , Beijing 100029, China South China Institute of Botany, Chinese Academy of Sciences, Guangzhou 510650, China | 1999 | Chinese Science Bulletin1999,44,3: | 7 |
| 20 | Chronology of environmental events over East Asia during the past 130 ka显示文摘In the transitional region between the Loess Plateau and deserts, 4 sections located respectively at Yuling, Hengshan, Dingbian and Huining of China are studied. The high-resolution paleoclimatic records obtained show that environmental events on varying time scales have happened over East Asia. These events are dated with the time scales established using the recently-developed approach of Automatic Orbital Tuning. This leads to the establishment of the chronology of the environmental events. | Zhongli Ding Jimin Sun Zhiwei Yu Dongsheng Liu | 1998 | Chinese Science Bulletin1998,43,21: | 6 |