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1云南宣威晚二叠世末生物灭绝期C1煤的地球化学特征显示文摘云南宣威雁塘煤矿晚二叠世末期C1煤层蕴含了二叠纪—三叠纪界线事件演化以及宣威肺癌高发原因方面的重要信息。本文对该矿C1煤层(包括三个分层——B1、B2和B3)进行了刻槽分层采样,采用X射线荧光光谱和电感耦合等离子体质谱测试了24个样品中常量和微量元素。利用偏光显微镜和带能谱的扫描电镜(SEMEDX)对煤中的显微组分及矿物组成进行微区分析,利用X射线衍射对低温灰化后的煤样作了矿物的半定量分析。结果表明,雁塘矿C1煤中常量元素Ca、Mn、Si含量明显高于中国煤均值;与华南二叠纪煤平均值、中国煤平均值、世界煤平均值以及地壳元素丰度相比较,雁塘矿C1煤中的W、Co、Mo、Cd、Pb、Be、Sb、Cu、Ni、Zn、Zr和V等12种微量元素相对比较富集。结合相关分析和SEM-EDX微区分析方法,对C1煤中微量元素的赋存状态进行分析发现Cs、Ga、Nb、Ba、Rb、Th、Tl、U与灰分显著正相关,表明这些元素主要以无机矿物态赋存,其它元素赋存状态复杂。结合C1煤中12种富集元素在垂向上的含量分布特征,推断Co、Cu、V、Zn应主要来源于峨眉山玄武岩风化产物;Be和Zr主要受同沉积火山灰影响;Ni则可能受峨眉山玄武岩风化及同沉积火山灰的共同影响;同沉积火山灰是C1煤中W来源之一;Sb可能受中低温热液的影响。C1煤中Zr与我国南方其他地区P/T界线粘土岩中Zr的富集规律一致。C1煤中富集的微量元素与宣威肺癌高发区可吸入颗粒物中的高含量元素一致,推断C1煤的燃烧可能与宣威肺癌高发有关。C1煤中富集的有毒有害微量元素可能与二叠纪—三叠纪之交生物大灭绝期的独特环境有密切关系。邵龙义 王娟 侯海海 张名泉 汪浩 SPIRO Baruch LARGE David 周义平 2015地质学报2015,89,1:17
2Performance prediction and flow analysis in the vaned distributor of a pump turbine under low flow rate in pump mode显示文摘The main goal of this work is to investigate the possible different flow patterns existing in pump turbine under off-design conditions in pump mode. Numerical simulations by solving the Navier-Stokes equation, coupled with the 'SST k-ω' turbulence model, were carried out. Flow characteristics were assumed to be stalled in the appropriate region of ?ow rate levels of Q/QD=0.15–0.61. The simulation result was compared with experimental data and they showed good agreement. Consequently, velocity fields in three axial locations in stay vanes and guide vanes were analysed in details. It was shown that 'jet-wake' flow pattern exists near the band, which changes little in the whole shape with flow rate increasing; to the middle location of vanes, reverse flow begins to appear on the interface between the runner and guide vanes, which will disappear gradually as the flow rate increases; massive reverse flow is captured near the crown, whose intensity will be weakened as the flow rate increases. Ultimately, it was found that the special head-flow profile can be ascribed to the special hydraulic loss characteristics of the stay vanes and guide vanes.YIN JunLian1, LIU JinTao1, WANG LeQin1, JIAO Lei1, WU DaZhuan1 & QIN DaQing2 1 Institute of Chemical Machinery, Department of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China 2 Harbin Institute of Large Electrical Machinery, Harbin 150001, China 2010Science China(Technological Sciences)2010,53,12:17
3中国西南地区晚二叠世泥炭地净初级生产力及其控制因素显示文摘米兰科维奇旋回理论是古环境研究中重要的时间'度量'工具。文中以贵州普安糯东17号煤层和云南富源天佑10号煤层为例,对晚二叠世煤层的地球物理测井信号进行频谱分析,以获得其中的米兰科维奇轨道周期参数。研究发现,测井信号所反映出的煤层灰分含量变化受泥炭地发育时期的米兰科维奇轨道周期(123ka(偏心率):35.6ka(斜率):21.2ka(岁差))驱动。以煤层剖面中的轨道周期为时间尺度,进一步计算出晚二叠世泥炭地的碳聚集速率为54.3~77.0gC/(m2.a),对应的净初级生产力(NPP)为543~1540gC/(m2.a)。基于晚二叠世、晚石炭世和现代热带泥炭地的NPP与各个时期大气成分的对比结果显示,大气中的二氧化碳和氧气含量对陆相生态系统的净初级生产力具有关键性的控制作用。邵龙义 汪浩 Large D J 2011古地理学报2011,13,5:14
4早白垩世泥炭地净初级生产力及其控制因素——来自二连盆地吉尔嘎郎图凹陷6号煤的证据显示文摘现代泥炭地中蕴藏着巨量的碳,泥炭地生产力的高低会影响全球碳循环及全球气候变化。前人对全新世以来泥炭地生产力做了大量研究,但对前第四纪的'深时'阶段的泥炭地生产力则极少涉及,其主要原因是缺少精确的定年方法。以二连盆地吉尔嘎郎图凹陷早白垩世6号煤为例,利用地球物理测井信号进行频谱分析并获得煤层中米兰科维奇旋回周期参数(123 ka(偏心率):38.1 ka(斜率):22.1 ka(岁差)),将米兰科维奇旋回作为'深时'地层时间的'度量'工具,计算出6号煤层碳的聚集速率为35.1~38.9 gC/(m^2·a),进一步推算出其所代表的泥炭地的碳聚集速率为46.2~51.2 gC/(m^2·a),净初级生产力(NPP)为231~256 gC/(m^2·a)。将该计算结果与全新世同一纬度带泥炭地生产力水平比较,并结合前人研究成果综合分析影响因素,得出早白垩世泥炭地生产力水平主要受温度和大气中二氧化碳含量控制,而这两种因素又与气候相关联,则泥炭地生产力的研究可能对进一步了解古气候提供帮助。闫志明 邵龙义 王帅 Large D J 汪浩 孙钦平 2016沉积学报2016,34,6:8
5Three-dimensional perfused human in vitro model of nonalcoholic fatty liver disease显示文摘AIM To develop a human in vitro model of non-alcoholic fatty liver disease(NAFLD), utilising primary hepatocytes cultured in a three-dimensional(3D) perfused platform. METHODS Fat and lean culture media were developed to directly investigate the effects of fat loading on primary hepatocytes cultured in a 3D perfused culture system. Oil Red O staining was used to measure fat loading in the hepatocytes and the consumption of free fatty acids(FFA) from culture medium was monitored. Hepatic functions, gene expression profiles and adipokine release were compared for cells cultured in fat and lean conditions. To determine if fat loading in the system could be modulated hepatocytes were treated with known anti-steatotic compounds. RESULTS Hepatocytes cultured in fat medium were found to accumulate three times more fat than lean cells and fat uptake was continuous over a 14-d culture. Fat loading of hepatocytes did not cause any hepatotoxicity and significantly increased albumin production. Numerous adipokines were expressed by fatty cells and genes associated with NAFLD and liver disease were upregulated including: Insulin-like growth factorbinding protein 1, fatty acid-binding protein 3 and CYP7A1. The metabolic activity of hepatocytes cultured in fatty conditions was found to be impaired and the activities of CYP3A4 and CYP2C9 were significantlyreduced, similar to observations made in NAFLD patients. The utility of the model for drug screening was demonstrated by measuring the effects of known antisteatotic compounds. Hepatocytes, cultured under fatty conditions and treated with metformin, had a reduced cellular fat content compared to untreated controls and consumed less FFA from cell culture medium.CONCLUSION The 3D in vitro NAFLD model recapitulates many features of clinical NAFLD and is an ideal tool for analysing the efficacy of anti-steatotic compounds.Tomasz Kostrzewski Terri Cornforth Sophie A Snow Larissa Ouro-Gnao Cliff Rowe Emma M Large David J Hughes 2017World Journal of Gastroenterology2017,23,2:6
6活性氧化铝除氟研究显示文摘针对目前活性氧化铝饮水除氟中存在的问题,进行了生产性试验研究,通过采用原水投加CO_2气体降低pH值、小颗粒活性氧化铝、大流量短历时的NaOH循环再生法等新技术,提高了活性氧化铝的吸附容量和处理水的能力,克服滤料板结和假疲劳,除氟效果稳定可靠,水质好,再生时间短,用药省,降低了基建投资和运转费用。North China Municipal Engineering Design Institute A full-scale plant was set up for studying the existing problems on the fluoride removal from drinking water by activated alumina. Some new methods was adopted,such as the addition of CO2to reduce water pH value,the use of small-sized activated alumina,and the employment of a cyclic regeneration at large flow rate with NaOH as regenerant,which result in the improvement of adsorption capacity of activated alumina and treatment capacity, the elimination of the hardening of filtration materials and false fatigue,stable and reliable effectiveness,good quality in water,short regeneration time,small consumption of regenerant. And then the capital and openational costs were reduced. 1989中国给水排水1989,5,3:5
7FOLFIRINOX and translational studies: Towards personalized therapy in pancreatic cancer显示文摘Pancreatic cancer is an extremely aggressive disease; although progress has been made in the last few years, the prognosis of these patients remains dismal. FOLFIRINOX is now considered a standard treatment in first-line setting, since it demonstrated an improved overall and progression-free survival vs gemcitabine alone. However, the enthusiasm over the benefit of this three-drug regimen is tempered by the associated increased toxicity profile, and many efforts have been made to improve the feasibility of this schedule. After a more recent phase Ⅲ trial showing an improved outcome over gemcitabine, the combination of gemcitabine/nab-paclitaxel emerged as another standard first-line treatment. However, this treatment is also associated with more side effects. In addition, despite initial promising data on the predictive role of SPARClevels, recent studies showed that these levels are not associated with nab-paclitaxel efficacy. The choice to use this treatment over FOLFIRINOX is therefore a topic of debate, also because no validated biomarkers to guide FOLFIRINOX treatment are available. In the era of actionable mutations and target agents it would be desirable to identify molecular factors or biomarkers to predict response to therapy in order to maximize the efficacy of treatment and avoid useless toxic effects for non-responding patients. However, until today the milestone of treatment for pancreatic cancer remains chemotherapy combinations, without predictive or monitoring tools existing to optimize therapy. This review analyzes the state-of-the-art treatments, promises and limitations of targeted therapies, ongoing trials and future perspectives, including potential role of microR NAs as predictive biomarkers.Chiara Caparello Laura L Meijer Ingrid Garajova Alfredo Falcone Tessa Y Le Large Niccola Funel Geert Kazemier Godefridus J Peters Enrico Vasile Elisa Giovannetti 2016World Journal of Gastroenterology2016,22,31:4
8SHRIMP zircon U-Pb ages from coal beds across the Permian-Triassic boundary, eastern Yunnan, southwestern China显示文摘The first SHRIMP zircon U e Pb ages from coal beds close to the end-Permian mass extinction are reported from the C_1 coal seam in the Yantang Mine in Laibin Town, Xuanwei County, eastern Yunnan Province.Zircons were extracted from kaolinite claystone layers, defined as tonsteins(volcanic ash deposits), in the subseam B_1 and B_3 of the coal seam C_1.The U-Pb ages are 252.0 ± 2.3 Ma and 250.3 ± 2.1 Ma for the sub-seam B_1 and B_3, respectively. Within analytical uncertainties, these U-Pb ages include the time period of the onset of the mass extinction at 251.941 ± 0.037 Ma, which was obtained from the marine Meishan section in Zhejiang Province, ~1600 km away from the Yantang Mine. These new ages represent not only the first and closest ages to the PTB mass extinction in terrestrial coal beds, but also ages from the nearest site to the Emeishan volcanoes investigated so far. Therefore these new data provide the most accurate stratigraphic horizon of terrestrial facies of the end-Permian extinction in South China. The Emeishan volcanoes were likely the source of volcanic ash in the coal seams at the Xuanwei County and broader areas in South China. Furthermore, the minerals and geochemistry characteristics of the C_1 coal seam also implied the influences of contemporaneous volcanic activities.Juan Wang Long-Yi Shao Hao Wang Baruch Spiro David Large 2018Journal of Palaeogeography2018,7,2:4
9The Cosmic Dust in Suzhou Granite:Ablated Products of a Cometary ExplosionHu Zhong-wei,Wang Er-kang,Wan Yu-qiuDepartement of Astronomy,Nanjing University,Nanjing 210093,China Department of Earth Sdence,Nanjing University,Nanjing 210093,China Cosmic dust has been collected in large number from deap-sea sediments,Greenland ice deposits,the stratosphere and space,of cosmic dust,some are the unmelted micrometeorite,and most are the ablated products of me-teoroids in the atmosphere.Cosmic dusts were recovered from two sites of the 1908 Tunguska explosion and the 1965 Revelstoks explosion Since 1987,a large number of microspherules have been extracted from Suzhou granite of China Their suface and section structures,mineral and chemical composition show that these microspherules are of the ablated cosmic dust.The microspherules occurred in the inner contact complex intrusion.It suggests that the microspherules may be products of the same event and were aggergated in some strata and then captured by the emplacement of granitic magma.Although the microspherules are similare to other ablated cosmic dusts,there are some diferences.Our calculated results of cometary motion through the atmosphere and explosion show that the microspherules may be the ablated dust of a comet with mass above 1015g at its explosion near the ground. 1996紫金山天文台台刊1996,15,3:2
10大型化肥厂尿素造粒测定报告显示文摘调查与测定了6个大化肥厂造粒和储运包装的运行情况。结果表明:锥形与斜孔喷头所造粒的合格率均在98%以上,横向喷洒密度分布均呈突出的驼峰状,斜孔喷头更为突出,两种喷头颗粒分布均呈现喷洒带外区为大颗粒,斜孔喷头所造颗粒在储运包装过程易粉化,锥形喷头塔顶排尘较大。Wang Shizhen (The Group of Report on Prilling Measurement of Large Scale Urea of Ministry of Chemical Industry and SINOPEC,Wuhan,430073) 1996大氮肥1996,19,6:2
11Suppression of host immune response by the core protein of hepatitis C virus: possible implications for hepatiits C virus persistence显示文摘Large M K Kittlesen D J Hahn Y S 1999J Immunol1999,162,2:2
12The inorganic geochemistry of a peat deposit on the eastern Qinghai-Tibetan Plateau and insights into changing atmospheric circulation in central Asia during the Holocene显示文摘Marion Ferrat Dominik J. Weiss Baruch Spiro David Large 2012Geochimica et Cosmochimica Acta2012,,:2
13Using geophysical logs to identify Milankovitch cycles and to calculate net primary productivity(NPP) of the Late Permian coals,western Guizhou,China显示文摘Milankovitch periodicities of 123 kyr(eccentricity), 35.6 kyr(obliquity), and 21.2 kyr(precession) were identified in geophysical logs of three Late Permian coals: 17#, 18#, and 17 + 18#, from the Songhe mining area in western Guizhou Province. Based on the astronomic temporal framework, the periods of deposition of the 17#(5.6 m), 18#(6.4 m), and 17 + 18#(5.4 m) coals were constrained to 140.8–119.8 kyr, 160–136.2 kyr, and 135–114.9 kyr,respectively. The overall depositional period of the 18# coal of 160–136.2 kyr was further subdivided using the wavelet analysis method, into short and precise periods corresponding to the Milankovitch periodicities. It includes one eccentricity periodicity(123 kyr), three obliquity periodicities(35.6 kyr), and five precession periodicities(21.2 kyr). Different thicknesses of the subdivided coal sections, equivalent to the same time span of deposition, indicate different rates of coal deposition, i.e., thicker sections imply higher rates while the thinner sections represent lower rates. The combination of the measured average carbon concentration with the density of the coals gave rise to long-term average values of carbon accumulation rates for the Late Permian coals, in the range of 42.4–50.6 g?C?m^(-2)?a^(-1). This range corresponds to the long-term average carbon accumulation rates for the initial peat in the range of 60.6–72.3 g?C?m^(-2)?a^(-1). Based on the known quantitative relation between net primary productivity(NPP)values and long-term average carbon accumulation rates for the Holocene tropical peatlands, the range of NPP values for the Late Permian tropical peatlands was estimated as 242.4–433.8 g?C?m^(-2)?a^(-1).A comparison of existing information about peatland NPP levels of various ages and latitudes indicated that when conditions of high rain and high humidity prevail in the palaeo-peatland at given latitude, the NPP rates will vary with changes in atmospheric concentration of CO_2 and O_2. This relationship may lead to the use of coals as an indicator for the concentration of these gases(CO_2 and O_2) in the contemporaneous atmosphere encompassing the long records of coal deposition.Zhi-Ming Yan Long-Yi Shao David Large Hao Wang Baruch Spiro 2019Journal of Palaeogeography2019,8,1:2
14Oceanic vertical mixing: a review and a model with a nonlocal boundary layer parameteriza tion显示文摘LARGE W MCWILLIAMS J DONEY S 1994Rev Geophys1994,32,4:1
15Striatal GDNF administration increases tyrosine hydroxylase phosphorylation in the rat striatum and substantia nigra显示文摘Salvatore MF Zhang JL Large DM 2004J Neurochem2004,90,1:1
16Measuring glycerol turnover,glu-coneogenesis from glycerol,and total gluconeogenesis withglycerol:role of the infusion-sampling mode显示文摘Peroni 0 Large V Odeon M 1996Metabolism1996,45,7:1
17Gold and trace element zonation in pyrite using a laser imaging technique: Implications for the timing of gold in orogenic and Carlin- style sediment- hosted deposits 显示文摘R R Large L Danyushevsky C Hollit V Maslennikov S Meffer S Gilbert S Bull R Scott P Emsbo H Thomas B Singh J Foster 2009Economic Geology2009,104,5:1
18Isoprenoid biosynthesis via a mevalonateindependent pathway in plants: cloning and heterologous expression of 1-deoxy-D-xylulose-5-phosphate reductoisomerase from peppermint显示文摘 Croteau R 1999Arch Biochem Biophys1999,365,:1
19Radio transmission to and from underground coal mines-theory and measurement 显示文摘LARGE B D BALL L 1973IEEE Transactions on Communications1973,21,3:1
20Comparison of the expression and activity of the lipogenic pathway in human and rat adipose tissue显示文摘Letexier D Pinteur C Large V 2003J Lipid Res2003,44,:1
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