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1China’s first deep manned submersible,JIAOLONG显示文摘A deep manned submersible is indispensable to deep ocean exploration. No other equipment can bring scientists to ex-treme sea floor depths to do research in situ. Marine geology, seafloor geophysics,marine biology,and oceanic chemistry are the fields that scientists are particularly eager to study [1-6]. Chinese scientists have long dreamed of using their own submersible to probe the deep sea. China’s recent fast development of a deep manned submersible has realized that dream.Liu, Feng Cui, WeiCheng Li, XiangYang 2010Science China Earth Sciences2010,53,10:24
2Screening for gastric cancer in China:Advances,challenges and visions显示文摘Gastric cancer(GC)is one of the major cancers in China and all over the world.Most GCs are diagnosed at an advanced stage with unfavorable prognosis.Along with some other countries,China has developed the government-funded national screening programs for GC and other major cancers.GC screening has been shown to effectively decrease the incidence of and mortality from GC in countries adopting nationwide screening programs(Japan and Korea)and in studies based on selected Chinese populations.The screening of GC relies mostly on gastroendoscopy,the accuracy,reliability and safety of which have been indicated by previous studies.However,considering its invasive screening approach,requirements on skilled endoscopists and pathologists,and a high cost,developing noninvasive methods to amend endoscopic screening would be highly needed.Numerous studies have examined biomarkers for GC screening and the combination of biomarkers involving pepsinogen,gastrin,and Helicobacter pylori antibodies has been proposed for risk stratification,seeking to narrow down the high-risk populations for further endoscopy.Despite all the achievements of endoscopic screening,evidence on appropriate screening age,intervals for repeated screening,novel biomarkers promoting precision prevention,and health economics need to be accumulated to inform policymakers on endoscopic screening in China.With the guide of Health China 2030 Planning Outline,we have golden opportunities to promote prevention and control of GC.In this review,we summarize the characteristics of screening programs in China and other East Asian countries and introduce the past and current approaches and strategies for GC screening,aiming for featuring the latest advances and key challenges,and illustrating future visions of GC screening.Xiaohan Fan Xiangxiang Qin Yang Zhang Zhexuan Li Tong Zhou Jingying Zhang Weicheng You Wenqing Li Kaifeng Pan 2021Chinese Journal of Cancer Research2021,33,2:21
3Conodont Evidence for the Age of the Panxian Fauna,Guizhou,China显示文摘Detailed conodont analysis on the Yangjuan-Chupiwa section,Xinmin,Panxian County,Guizhou Province,revealed a conodont sequence including four Anisian conodont zones,viz.Nicoraella germanica Zone,Nc.kockeli Zone,Paragondolella bifurcata Zone and Neogondolella constricta Zone.These zones indicate that the upper Guanling Formation consists of strata from the Bithynian to the Illyrian of the Anisian.Appearance of Neogondolella constricta suggests that the Anisian/Ladinian boundary might be in the overlying Yangliujing Formation.The Panxian Fauna with well-preserved marine reptile and fish fossils is proved to belong to the lower part of the conodont Nc.kockeli Zone in the studied area.Thus,the age of the Panxian Fauna could be the early Pelsonian of the Anisian.SUN Zuoyu SUN Yuanlin HAO Weicheng JIANG Dayong 2006Acta Geologica Sinica(English Edition)2006,80,5:19
4A cellular automata evacuation model considering friction and repulsion显示文摘There exist interactions among pedestrians and between pedestrian and environment in evacuation. These interactions include attraction, repulsion and friction that play key roles in human evacuation behaviors, speed and efficiency. Most former evacuation models focus on the attraction force, while repulsion and friction are not well modeled. As a kind of multi-particle self-driven model, the social force model introduced in recent years can represent those three forces but with low simulation efficiency because it is a continuous model with complex rules. Discrete models such as the cellular automata model and the lattice gas model have simple rules and high simulation efficiency, but are not quite suitable for interactions’ simulation. In this paper, a new cellular automata model based on traditional models is introduced in which repulsion and friction are modeled quantitatively. It is indicated that the model can simulate some basic behaviors, e.g. arching and the “faster-is-slower” phenomenon, in evacuation as multi-particle self-driven models, but with high efficiency as the normal cellular automata model and the lattice gas model.SONG Weiguo YU Yanfei FAN Weicheng Zhang Heping 2005Science China(Technological Sciences)2005,48,4:19
5Biodiversity and Sequence of the Middle Triassic Panxian Marine Reptile Fauna,Guizhou Province,China显示文摘中间的三叠纪的 Panxian 动物志是一个物理标记和在结束以后跟随早三叠纪的停滞阶段的三叠纪的海洋的生态系统的快速的恢复的代表性的记录 -- 二叠的集体扑灭。十海洋的爬行动物税一在 Guanling 形成的上面的成员从 1.82 2.10 m 厚的含化石的水平被发现了,它能在石块爬行动物的 stratigraphic 分布上通过分析被细分进三张海洋的爬行动物床。更低的爬行动物床产出 sauropterygians Placodus inexpectatus 江等, 2008 并且 Lariosaurus hongguoensis 江等, 2006, ichthyopterygians Xinminosaurus catactes 江等, 2008 并且 Phalarodon cf。Phalarodon fraasi Merriam, 1910,与 Mixosaurus panxianensis 江等联系了, 2006,代表 durophagous 的优势的一个阶段税一。在这张床上,大完全的骨骼可以在长度到达多达 2.3 m,并且岩相和 chemostratigraphic 分析在底部,以及升起的海水平附近与 oxic 水环境显示一个相对深的碳酸盐平台。中间的爬行动物床产出 sauropterygian Nothosaurus yangjuanensis 江等, 2006 并且祖龙 Qianosuchus mixtus 李等, 2006,把等与 Mixosaurus panxianensis 江联系了, 2006。在这张床上的石块被它的大头针 cering 出牙和大全面身体尺寸描绘,与最大可能在长度超过 3 m。这张床可能在底部附近与相对缺氧的状况代表最深的盆的一时间。上面的爬行动物床产出 sauropterygians Wumengosaurus delicatomandibularis 江等, 2008, Keichousaurus sp, protorosaur Dinocephalosaurus 东方人是李, 2003,并且 ichthyopterygian Mixosaurus panxianensis 江等, 2006。在这张床上,爬虫税一由吸喂描绘了出现,并且最长是不到 1 m。这张床对应于减少的水深度的一个时期。JIANG Dayong Ryosuke MOTANI HAO Weicheng Olivier RIEPPEL SUN Yuanlin Andrea TINTORI SUN Zuoyu Lars SCHMITZ 2009Acta Geologica Sinica(English Edition)2009,83,3:17
6Cellular automata pedestrian movement model considering human behavior显示文摘The pedestrian movement is more complex than vehicular flow for the reason that people are more flexible and intelligent than car. Without the limit of 搇anes?pedestrian movement is loose and free. Furthermore, they are easily affected by other walkers as well as the environ-ment around. In this paper some special technique is intro-duced considering human behavior to make the rules more reasonable. By simulating the two-dimension pedestrian movement, the phase transition phenomena of pedestrian movement, including the up walkers moving from the bottom to the upper boundary and the right walkers moving from the left to the right boundary, are presented. Studying on the effect of the system size on the critical density shows that the critical density is independent of the system size in the scope studied in this paper.YANG Lizhong, FANG Weifeng, LI Jian, HUANG Rui & FAN Weicheng State Key Laboratory of Fire Science, University of Science and Tech-nology of China, Hefei 230026, China Correspondence should be addressed to Yang Lizhong (e-mail:zxd@ustc. edu.cn) 2003Chinese Science Bulletin2003,48,16:16
7A 3D bounding surface model for rockfill materials显示文摘A 3D bounding surface model is established for rockfill materials,which can be applied to appropriately predict the deformation and the stabilization of rockfill dams.Firstly,an associated plastic flow rule for rockfill materials is investigated based on the elaborate data from the large-style triaxial compression tests and the true triaxial tests.Secondly,the constitutive equations of the 3D bounding surface model are established by several steps.These steps include the bounding surface incorporating the general nonlinear strength criterion,stress-dilatancy equations,the evolution of the bounding surface and the bounding surface plasticity.Finally,the 3D bounding surface model is used to predict the mechanical behaviors of rockfill materials from the large-style triaxial compression tests and the true triaxial tests.Consequently,the proposed 3D bounding surface model can well capture such behaviors of rockfill materials as the strain hardening,the post-peak strain softening,and the volumetric strain contraction and expansion in both two-and three-dimensional stress spaces.XIAO Yang LIU HanLong ZHU JunGao SHI WeiCheng LIU MengCheng 2011Science China(Technological Sciences)2011,54,11:16
8Self-organized criticality of forest fires in China显示文摘Self-organized criticality(SOC) of forest fires in China from 1950 to 1989 is studied. The stability, scale-invariant character of SOC and external effects on SOC of forest fires in China are analyzed in detail. Forest-fire cellular automata model is a typical model for the research of SOC. Based on the traditional forest-fire model, an improved model, in which effects of tree species, meteorological conditions and human efforts on forest fires are considered, is introduced. Actual forest fire data in China are compared with simulation results of the two models. It is shown that forest fire data in China have SOC behavior and simulation results of the improved model accord better with actual forest fire data than those of the traditional model.Song Weiguo Fan Weicheng Wang Binghong 2001Chinese Science Bulletin2001,46,13:15
9Laser beam induced current microscopy and photocurrent mapping for junction characterization of infrared photodetectors显示文摘For non-destructive optical characterization, laser beam induced current(LBIC) microscopy has been developed into as a quantitative tool to examine individual photodiodes within a large pixel array. Two-dimensional LBIC microscopy, also generally called photocurrent mapping(PC mapping), can provide spatially resolved information about local electrical properties and p-n junction formation in photovoltaic infrared(including visible light) photodetectors from which it is possible to extract material and device parameters such as junction area, junction depth, diffusion length, leakage current position and minority carrier diffusion length etc. This paper presents a comprehensive review of research background, operating principle, fundamental issues, and applications of LBIC or PC mapping.QIU WeiCheng HU WeiDa 2015Science China(Physics,Mechanics & Astronomy)2015,58,2:15
10Progress in research and application of water mist fire suppression technology显示文摘Water mist technology in fire suppression has been a subject of many investigations over the last decade. This paper introduces the concept of water mist technology and discusses its extinguishment mechanisms in comparison with other fire suppression systems briefly. A survey is made on the recent applications of water mist for (1) Class B spray and pool fires in machinery spaces, gas turbine enclosures, combat vehicles, and flammable liquid storage rooms; (2) Class A fires in residential occupancies, marine accommoda-tions and public spaces, heritage buildings and libraries; (3) Class C fires in electronic equipment and computer rooms; and (4) the fires in aircraft onboard cabin and cargo com-partments. The paper proceeds to review some new applica-tions of water mist for the Class K fires in commercial cook rooms. Use of water mist for total-ship protection as well as the fire protection of heavy goods vehicle shuttle trains is also investigated. At last, the up-to-date development of corresponding test to evaluate the capabilities and limitaions of water mist is discussed.LIU Jianghong, LIAO Guangxuan, LI Peide, FAN Weicheng & LU Qiang State Key Laboratory of fire Science, University of Science and Tech-nology of China, Hefei 230026, China Correspondence should be addressed to Liu Jianghong (e-mail: ljh@ ustc.edu.cn) 2003Chinese Science Bulletin2003,48,8:15
11New primitive ichthyosaurian (Reptilia,Diapsida) from the Middle Triassic of Panxian,Guizhou,southwestern China and its position in the Triassic biotic recovery显示文摘一张新原始 ichthyopterygian Xinminosaurus catactes 情报。et sp。nov。在 Panxian 从 Guanling 形成的中间的三叠纪的上面的成员基于一架完全的骨骼被树立,贵州,西南的中国。它在它的出牙,尺骨,腕骨和 tarsals 有特别地导出的人物的一间套房。它类似于在保留伸长的手足骨头的原始 ichthyopterygians。新税在上和多种水兵在 Panxian 动物志的爬行动物是中间的三叠纪的关於生命的放射的物理标记。这动物志的详细研究将在差异,迁居和中间的三叠纪的 ichthyopterygians 的 paleobiogeographic 亲密关系上供应必要知识。Dayong Jiang Ryosuke Motani Weicheng Hao Lars Schmitz Olivier Rieppel Yuanlin Sun Zuoyu Sun 2008Progress in Natural Science:Materials International2008,18,10:13
12Responses of root growth of Alhagi sparsifolia Shap. (Fabaceae) to different simulated groundwater depths in the southern fringe of the Taklimakan Desert, China显示文摘Alhagi sparsifolia Shap. (Fabaceae) is a spiny, perennial herb. The species grows in the salinized, arid regions in North China. This study investigated the response characteristics of the root growth and the distribution of one-year-old A. sparsifolia seedlings to different groundwater depths in controlled plots. The ecological adaptability of the root systems of A. sparsifolia seedlings was examined using the artificial digging method. Results showed that: (1) A. sparsifolia seedlings adapted to an increase in groundwater depth mainly through increasing the penetration depth and growth rate of vertical roots. The vertical roots grew rapidly when soil moisture content reached 3%-9%, but slowly when soil moisture content was 13%-20%. The vertical roots stopped growing when soil moisture content reached 30% (the critical soil moisture point). (2) The morphological plasticity of roots is an important strategy used by A. sparsifolia seedlings to obtain water and adapt to dry soil conditions. When the groundwater table was shallow, horizontal roots quickly expanded and tillering increased in order to compete for light resources, whereas when the groundwater table was deeper, vertical roots developed quickly to exploit space in the deeper soil layers. (3) The decrease in groundwater depth was probably responsible for the root distribution in the shallow soil layers. Root biomass and surface area both decreased with soil depth. One strategy of A. sparsifolia seedlings in dealing with the increase in groundwater depth is to increase root biomass in the deep soil layers. The relationship between the root growth/distribution of A. sparsifolia and the depth of groundwater table can be used as guidance for harvesting A. sparsifolia biomass and managing water resources for forage grasses. It is also of ecological significance as it reveals how desert plants adapt to arid environments.FanJiang ZENG Cong SONG HaiFeng GUO Bo LIU WeiCheng LUO DongWei GUI Stefan ARNDT DaLi GUO 2013Journal of Arid Land2013,5,2:13
13S phase-dependent interaction with DNMT1 dictates the role of UHRF1 but not UHRF2 in DNA methylation maintenance显示文摘最近的研究证明 UHRF1 被指向 DNMT1 到 DNA 复制 foci 为 DNA methylation 维护要求,大概通过它的唯一的半甲醇化物有 DNMT1 的 DNA 有约束力的活动和相互作用。UHRF2, UHRF 家庭蛋白质的另一个成员,高度类似于在顺序和结构的 UHRF1,关于它在 DNA methylation 的角色的涨的问题。在这研究,我们证明 UHRF2 象 UHRF1 一样,也优先地绑在 methylated histone H3 离氨酸 9 (H3K9 ) 通过它的保存 tudor,通过 SET 和戒指的领域和半甲醇化物 DNA 联系了领域。象 UHRF1 一样, UHRF2 在 pericentric heterochromatin 被充实。heterochromatin 本地化取决于到大程度它的 methylated H3K9 有约束力的活动并且到它的 methylated 上的更少的程度 DNA 有约束力的活动。Coimmunoprecipitation 实验证明 UHRF1 和 UHRF2 与 DNMT1, DNMT3a, DNMT3b 和 G9a 交往。尽管有所有这些保存功能,我们发现 UHRF2 不能在 Uhrf1 空老鼠救 DNA methylation 缺点胚胎的干细胞。这个罐头在房间周期的 S 阶段期间为 UHRF2 被归因于无能到成员 DNMT1 到复制 foci。确实,我们发现当 UHRF1 在房间以一种 S 阶段依赖者方式与 DNMT1 交往时, UHRF2 不做。因此,我们的学习证明 UHRF2 和 UHRF1 不在 DNA methylation 维护是机能上地冗余的并且作为为 DNA methylation 指向 DNMT1 的关键规章的机制揭示在 UHRF1 和 DNMT1 之间的 cell-cycle-dependent 相互作用。Jiqin Zhang Qinqin Gao Pishun Li Xiaoli Liu Yuanhui Jia Weicheng Wu Jiwen Li Shuo Dong Haruhiko Koseki Jiemin Wong 2011Cell Research2011,21,12:12
14Cold acclimation improves photosynthesis by regulating the ascorbate–glutathione cycle in chloroplasts of Kandelia obovata显示文摘As the most northerly mangrove species in China, Kandelia obovata may undergo extreme cold event stress. Enhancing the cold tolerance of this species is crucial to its successful afforestation. This study aimed to determine the resistance of K. obovata seedlings to low temperature stress by cold acclimation and to explain the mechanisms for alleviating cold injury. To understand these mechanisms, seedlings that were acclimatized and not acclimatized were exposed to 5℃/- 2℃(day/night)for 48 h.Results showed that low temperature stress reduced leaf photosynthesis of non-acclimatized seedlings by inducing oxidative stress and structural damage to chloroplasts. These phenomena were shown by increasing levels of malondialdehyde (MDA), O2-and H2O2, as well as decreasing enzyme activities in the ascorbate–glutathione (AsA-GSH) cycle. However, cold-acclimatized seedlings had improved photosynthetic rates and efficiency of photosystem II (PSII) under low temperature stress. Compared with non-acclimatized seedlings, leaves of coldacclimatized seedlings under low temperature stress for 48 h exhibited higher anti-oxidative enzyme activities, lower levels of O2^- and H2O2, less damage to chloroplast structure, and removed 33.7% of MDA at low temperature stress for 48 h. The data indicate that cold acclimation enhances photosynthetic capacity by effectively regulating activation in the PSII electron transport and the AsA–GSH cycle to scavenge excess ROS in chloroplasts, while the latter is more important.Weicheng Liu Chunfang Zheng Jinong Chen Jianbiao Qiu Zhixing Huang Qi Wang Yong Ye 2019Journal of Forestry Research2019,30,3:11
15Guanling Biota: A Marker of Triassic Biotic Recovery from the end-Permian Extinction in the Ancient Guizhou Sea显示文摘After a slow recovery from the end-Permian extinction during the Early Triassic and rapid radiation in the Middle Triassic, evolution of organisms reached a new peak phase in the Late Triassic. The Guanling Biota from the Wayao Member (conodont Paragondolella polygnathiformis Zone), Falang Formation, Xinpu, Guanling County, Guizhou Province, southwestern China corresponds to this peak that marks the full recovery from the end-Permian extinction of marine ecosystems. The biota is of high diversity, containing well preserved and completely articulated skeletons of vertebrates comprising marine reptiles, fishes, and invertebrates including crinoids, ammonites, bivalves, and other fossils, and is one of the best examples of marine ecosystem records in life history. The fossil marine reptiles and crinoids are most significant in this biota, especially the marine reptiles, which provide an important link between the Triassic Pacific and Tethys, and between Triassic basal forms and the Jurassic-Cretaceous marine top predators. The most remarkable fossils are the large completely articulated ichthyosaur skeletons up to and more than 10 m, and the first recorded thalattosaurs and placodonts in China. Following our review, of the 17 named reptilian taxa the eight listed here are considered to be valid: three ichthyosaurs (Qianichthyosaurus zhoui Li, 1999; Guizhouichthyosaurus tangae Cao and Luo in Yin et al., 2000, Guanlingsaurus liangae Yin in Yin et al., 2000), three thalattosaurs (Anshunsaurus huangguoshuensis Liu, 1999, Xinpusaurus suni Yin in Yin et al., 2000, Xinpusaurus kohi Jiang et al., 2004), and two placodonts (Sinocyamodus xinpuensis Li, 2000, Psephochelys polyosteoderma Li and Rieppel, 2002). Mixosaurus guanlingensis Cao in Yin et al., 2000 might be a junior synonym of Qianichthyosaurus zhoui Li, 1999, and Cymbospondylus asiaticus Li and You, 2002 and Panjiangsaurus epicharis Chen and Cheng, 2003 might be junior synonyms of Guizhouichthyosaurus tangae Cao and Luo in Yin et al., 2000. It needs to re-describe the holotypes after a complete preparation for clarifying the taxonomic status of Typicusichthyosaurus tsaihuae Yu in Yin et al., 2000, Xinpusaurus bamaolinensis Cheng, 2003, Neosinosaurus hoangi (Zhou in Yin et al., 2000), Wayaosaurus geei Zhou in Yin et al., 2000, Wayaosaurus bellus Zhou in Yin et al., 2000 and Placochelys ? minutus Yin and Luo in Yin et al., 2000.JIANG Dayong Ryosuke MOTAN LI Chun HAO Weicheng SUN Yuanlin SUN Zuoyu Lars SCHMITZ 2005Acta Geologica Sinica(English Edition)2005,79,6:11
16Precipitation seesaw phenomenon and its formation mechanism in the eastern and western parts of Northwest China during the flood season显示文摘Extending across three major plateaus,namely the Qinghai-Tibetan Plateau,the Inner Mongolia-Xinjiang Plateau and the Loess Plateau,Northwest China has the complex terrain and spatio-temporal climate variations,and is affected by the interactions among different circulation systems,such as the summer monsoon,the westerlies and the plateau monsoon.The understanding of the climate variability,as well as its characteristics and evolution mechanisms in this area has been limited so far.In this paper,the precipitation characteristics and mechanisms in the eastern and western parts of Northwest China during the flood season are compared and analyzed based on the data from 192 national meteorological observational sites in Northwest China in 1961-2016.The results show that,divided by the northern boundary of the East Asian summer monsoon,there are huge differences in the precipitation variation characteristics between the eastern and western parts.The inter-annual variations,interdecadal variations and total trends in the two parts all show a significant seesaw phenomenon.Moreover,it is found that the seesaw phenomenon of precipitation variation is closely related to the opposite variation between the East Asian summer monsoon index(MI)and the westerly circulation index(WI).In addition,the inverse variations on different time scales are only related to the contributions of precipitation at specific grades.Besides,in the two matching patterns of precipitation in the seesaw phenomenon,the middle and high latitudes are occupied by the'high-low-high'wave trains in the precipitation increases in the east of Northwest China(ENWC)and decreases in the west of Northwest China(WNWC)pattern,meaning precipitation increases in ENWC and decreases in WNWC.Whereas the opposite'low-high-low'wave trains at 500 hPa height are observed in the middle and high latitudes in the WH-EA pattern at 500 hPa height,meaning precipitation increases in WNWC and decreases in ENWC.Thus,the atmosphere circulation situation with two wave train types can support both the precipitation seesaw phenomenon and the opposite variation between MI and WI.Moreover,the seesaw phenomenon is shown to be related to the separate or joint effects of the South Asian High,ENSO and the plateau heating on the common but opposite effect on the summer monsoon and the westerlies,in which the South Asian High probably plays a more critical role.This study could deepen the scientific understanding of precipitation mechanisms and improve the weather forecast technology in Northwest China during the flood season.Qiang ZHANG Jingjing LIN Weicheng LIU Lanying HAN 2019Science China Earth Sciences2019,62,12:11
17A systematic review of metabolomic profiling of gastric cancer and esophageal cancer显示文摘Objective:Upper gastrointestinal(UGI)cancers,predominantly gastric cancer(GC)and esophageal cancer(EC),are malignant tumor types with high morbidity and mortality rates.Accumulating studies have focused on metabolomic profiling of UGI cancers in recent years.In this systematic review,we have provided a collective summary of previous findings on metabolites and metabolomic profiling associated with GC and EC.Methods:A systematic search of three databases(Embase,PubMed,and Web of Science)for molecular epidemiologic studies on the metabolomic profiles of GC and EC was conducted.The Newcastle–Ottawa Scale(NOS)was used to assess the quality of the included articles.Results:A total of 52 original studies were included for review.A number of metabolites were differentially distributed between GC and EC cases and non-cases,including those involved in glycolysis,anaerobic respiration,tricarboxylic acid cycle,and protein and lipid metabolism.Lactic acid,glucose,citrate,and fumaric acid were among the most frequently reported metabolites of cellular respiration while glutamine,glutamate,and valine were among the most commonly reported amino acids.The lipid metabolites identified previously included saturated and unsaturated free fatty acids,aldehydes,and ketones.However,the key findings across studies to date have been inconsistent,potentially due to limited sample sizes and the majority being hospital-based case-control analyses lacking an independent replication group.Conclusions:Studies on metabolomics have thus far provided insights into etiological factors and biomarkers for UGI cancers,supporting the potential of applying metabolomic profiling in cancer prevention and management efforts.Sha Huang Yang Guo Zhexuan Li Yang Zhang Tong Zhou Weicheng You Kaifeng Pan Wenqing Li 2020Cancer Biology & Medicine2020,17,1:11
18Modeling and behaviours of rockfill materials in three-dimensional stress space显示文摘A bounding surface model incorporating a unified nonlinear strength criterion is proposed.The proposed bounding surface model contains 9 model parameters,which can be determined from the conventional triaxial tests.The bounding surface model can reproduce such behaviours as the strain hardening,the post-peak strain softening,and the volumetric strain contraction and expansion.Based on the comparisons between the predictions and the test results,the proposed strength criterion and model can well reproduce the experimental results of the strength and stress-strain behaviours of rockfill material in three-dimensional stress space.The strength behaviour of rockfill material is summarized as:(a) the failure stress ratio decreases with the initial confining pressure on the meridian plane;(b) the failure deviatoric stress decreases with the Lode angle from 0o to 60o on the deviatoric plane.The stress ratio decreases with increasing one of such factors as the initial void ratio,the intermediate principal stress ratio and the minor principal stress at the same strain when the other factors are given.XIAO Yang LIU HanLong ZHU JunGao SHI WeiCheng 2012Science China(Technological Sciences)2012,55,10:10
19Adsorption of VOCs on reduced graphene oxide显示文摘A modified Hummer's method was adopted for the synthesis of graphene oxide(GO) and reduced graphene oxide(rGO). It was revealed that the modified method is effective for the production of GO and rGO from graphite. Transmission electron microscopy(TEM) images of GO and rGO showed a sheet-like morphology. Because of the presence of oxygenated functional groups on the carbon surface, the interlayer spacing of the prepared GO was higher than that of rGO. The presence of \OH and C_O groups in the Fourier transform infrared spectra(FTIR) spectrum and G-mode and 2D-mode in Raman spectra confirmed the synthesis of GO and rGO. rGO(292.6 m^2/g) showed higher surface area than that of GO(236.4 m^2/g). The prepared rGO was used as an adsorbent for benzene and toluene(model pollutants of volatile organic compounds(VOCs)) under dynamic adsorption/desorption conditions. rGO showed higher adsorption capacity and breakthrough times than GO. The adsorption capacity of rGO for benzene and toluene was 276.4 and 304.4 mg/g, respectively.Desorption experiments showed that the spent rGO can be successfully regenerated by heating at 150.0°C. Its excellent adsorption/desorption performance for benzene and toluene makes rGO a potential adsorbent for VOC adsorption.Lian Yu Long Wang Weicheng Xu Limin Chen Mingli Fu Junliang Wu Daiqi Ye 2018Journal of Environmental Sciences2018,30,5:10
20Activation of paternally expressed imprinted genes in newly derived germline-competent mouse parthenogenetic embryonic stem cell lines显示文摘单性生殖的胚胎的茎(足) 细胞为学习位于印的 genomic 下面的分子的机制提供一个珍贵试管内模型系统。然而,足房间的 thepluripotency 和父亲一般地表示的印的基因的表示侧面一直不是充分探索了。在这研究,三根老鼠足房间线被建立,在扩大文化的这些房间的区别潜力被评估。无差别的房间有正常核型和同型结合的染色体,并且表示了 ES-cell-specific 分子的标记。房间在超过 50 个段落以后仍然保持无差别并且展出了 pluripotentdifferentiation 能力。确定的 ES 房间的所有三根线生产了 teratomas;ES 房间的二根线生产了怪物和细菌线传播。而且,在这些房间的父亲一般地表示的印的基因 Snrpn, U2af1-rs1, Peg3,影响, Zfp127, Dlk1 和 Mest 的激活被检测。父亲一般地表示的印的基因被发现在单性生殖的联盟者的胚囊阶段被表示的一些激活胚胎试管内,他们的表示水平与扩大的足细胞培养增加了。而且,我们在足房间的这些父亲一般地表示的印的基因的激活在 ther 的甲基化与一个变化被联系的数据表演鼓舞了差别 methylated 区域。这些调查结果为足房间的 thepluripotency 提供直接证据并且在足房间表明在脱氧核糖核酸甲基化模式和父亲一般地表示的印的基因的激活之间的协会。因此,确定的 ES 房间线为在哺乳动物的开发学习 epigenetic 规定提供一个珍贵模型。Hua Jiang Bowen Sun Weicheng Wang Zhihong Zhang Furong Gao Guilai Shi Bing Cui XiangyinKong Zhao He Xiaoyan Ding Ying Kuang Jian Fei Yi Juan Sun Yun Feng Ying Jin 2007Cell Research2007,17,9:10
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