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MicroRNAs as possible biomarkers for diagnosis and prognosis of hepatitis b- and c-related-hepatocellularcarcinoma 被引量:25
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作者 Sirio Fiorino Maria Letizia Bacchi-Reggiani +17 位作者 Michela Visani Giorgia Acquaviva Adele Fornelli Michele Masetti Andrea Tura Fabio Grizzi Matteo Zanello Laura Mastrangelo Raffaele Lombardi Luca Di Tommaso Arrigo Bondi Sergio Sabbatani Andrea Domanico Carlo Fabbri Paolo Leandri Annalisa Pession Elio Jovine Dario de Biase 《World Journal of Gastroenterology》 SCIE CAS 2016年第15期3907-3936,共30页
Aim of the present review is to summarize the current knowledge about the potential relationship between mi RNAs and hepatitis B virus(HBV)-hepatitis C virus(HCV) related liver diseases. A systematic computerbased sea... Aim of the present review is to summarize the current knowledge about the potential relationship between mi RNAs and hepatitis B virus(HBV)-hepatitis C virus(HCV) related liver diseases. A systematic computerbased search of published articles, according to the Preferred Reporting Items for Systematic reviews and Meta-Analysis Statement, was performed to identify relevant studies on usefulness of serum/plasma/urine mi RNAs, as noninvasive biomarkers for early detection of HBV and HCV-induced hepatocellular carcinoma(HCC) development, as well as for its prognostic evaluation. The used Medical Subject Headings terms and keywords were: "HBV", "HCV", "hepatocellular carcinoma", "micro RNAs", "mi RNAs", "diagnosis", "prognosis", "therapy", "treatment". Some serum/plasma mi RNAs, including mi R-21, mi R-122, mi-125a/b, mi R-199a/b, mi R-221, mi R-222, mi R-223, mi R-224 might serve as biomarkers for early diagnosis/prognosis of HCC, but, to date, not definitive results or well-defined panels of mi RNAs have been obtained. More well-designed studies, focusing on populations of different geographical areas and involving larger series of patients, should be carried out to improve our knowledge on the potential role of mi RNAs for HCC early detection and prognosis. 展开更多
关键词 HEPATITIS B VIRUS HEPATITIS C VIRUS HEPATOCELLULAR CARCINOMAS Liver diseases MICRORNAS Review
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Calabrian and Ionian: A proposal for the definition of Mediterranean stages for the Lower and Middle Pleistocene 被引量:1
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作者 Maria Bianca Cita Luca Capraro +5 位作者 Neri Ciaranfi Enrico Di Stefano Maria Marino Domenico Rio Rodolfo Sprovieri Gian Battista Vai 《Episodes》 SCIE 2006年第2期107-114,共8页
关键词 卡拉布里亚 爱奥尼亚 地中海 更新世
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Functional group resolved NMR relaxation of 3-carbon adsorbates in mesoporous alumina
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作者 Neil Robinson Carmine D’Agostino Michael LJohns 《Magnetic Resonance Letters》 2023年第3期248-255,I0004,共9页
NMR relaxation analysis provides a unique and non-invasive probe of fluid dynamics within porous materials,and may be applied to the interpretation of a wide variety of material and interfacial characteristics.Here,we... NMR relaxation analysis provides a unique and non-invasive probe of fluid dynamics within porous materials,and may be applied to the interpretation of a wide variety of material and interfacial characteristics.Here,we report two-dimensional^(1)H T_(1)-T_(2)relaxation correlation measurements of a range of three-carbon adsorbates(1-propanol,2-propanol and propanoic acid)imbibed within the mesoporous metal oxide gamma-alumina.Our data,acquired across field strengths of 2 MHz,12.7 MHz and 43 MHz,clearly reveal two populations in each measurement,identified as the alkyl and hydroxyl moieties of each adsorbate.These results expand the range of materials in which such functional group resolved relaxation is known to occur,and demonstrate the clear persistence of such phenomena using a range of typical benchtop NMR systems employed to study fluid-saturated porous media. 展开更多
关键词 NMR relaxation ADSORPTION Porous media Low-field NMR
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致密陡谱源的甚长基线50厘米“快拍”观测 被引量:1
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作者 南仁东 R.T.Schilizzi C.and R.Fanti 《天文学报》 CSCD 北大核心 1990年第3期260-266,共7页
甚长基线干涉50 cm24个致密陡谱源的观测是我们小组近年来主要的研究课题之一.此文报导了使用全球网进行快拍观测的课题提出、观测程序设计以及观测的运行结果,同时也对残缺uv覆盖的图象恢复技术方法进行了研究.
关键词 甚长基线干涉 致密陡谱源 快拍模式
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5个CSS源50cm VLBI观测数据的再处理
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作者 蔡正东 彭勃 +5 位作者 南仁东 R. T. Schilizzi C. Fanti R. Fanti M. Inoue S. Kameno 《天体物理学报》 CSCD 1992年第4期332-339,共8页
本文给出了全球VLBI网50cm数据成图再处理的部分结果.样本包括5个CSS射电源:3C43、3C138、3C186、3C216和3C237.为了便于比较,同时给出了二次成图处理后的图象.通过对这些源的形态描述,并且通过与其它波段高分辨率图的对照,核实了再处... 本文给出了全球VLBI网50cm数据成图再处理的部分结果.样本包括5个CSS射电源:3C43、3C138、3C186、3C216和3C237.为了便于比较,同时给出了二次成图处理后的图象.通过对这些源的形态描述,并且通过与其它波段高分辨率图的对照,核实了再处理图上各子源的位置,这些低频观测细节,对更好地了解CSS源的本质无疑是十分有益的。 展开更多
关键词 射电源 VLBI 观测 图象处理
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VLBI总体条纹拟合方法的应用及其效果
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作者 蔡正东 彭勃 +5 位作者 南仁东 R.T.Schilizzi C.Fanti R.Fanti M.Inoue S.Kameno 《天体物理学报》 CSCD 1993年第2期184-192,共9页
用总体条纹拟合求解各天线的延迟量和条纹率参数,可以提高与小天线相关基线的灵敏度。本文以射电致密陡谱源(CSS)3C43为例,就如何提高数据的信噪比,尽可能多地保留有效数据方面做了成功的尝试.从而十分有效地使用了总体条纹拟合方法.我... 用总体条纹拟合求解各天线的延迟量和条纹率参数,可以提高与小天线相关基线的灵敏度。本文以射电致密陡谱源(CSS)3C43为例,就如何提高数据的信噪比,尽可能多地保留有效数据方面做了成功的尝试.从而十分有效地使用了总体条纹拟合方法.我们认为:对源结构的预知,配以恰当的处理技巧,能获取更多射电源结构信息,改善成图质量. 展开更多
关键词 天体物理方法 VLBI 数据处理
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不稳定粘土斜坡孔隙水监测初步分析
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作者 A. Simoni M. Berti +4 位作者 M. Generali C. Elmi M. Ghirotti 史二岭(翻译) 文宝萍(翻译) 《水文地质工程地质技术方法动态》 2006年第1期24-32,23,共10页
我们通过监测位于亚平宁地区的一个粘土斜坡内正孔隙水压力来分析降水如何影响沿土体剖面的孔隙压力分布,从而影响斜坡稳定性。监测数据在监测滑坡活动的第一个季节(2001年8月-2002年6月)获得。研究地点位于一个复杂滑坡后缘,该处... 我们通过监测位于亚平宁地区的一个粘土斜坡内正孔隙水压力来分析降水如何影响沿土体剖面的孔隙压力分布,从而影响斜坡稳定性。监测数据在监测滑坡活动的第一个季节(2001年8月-2002年6月)获得。研究地点位于一个复杂滑坡后缘,该处斜坡即将发生浅层滑坡,斜坡变形特征非常明显。 孔隙水压力数据的初步分析显示,过去11个月其变化呈现稳定的趋势。在寒冷潮湿的季节里,饱和带通常延伸到接近地表(小于1m)。孔隙水压力测量显示,任何条件下,整个斜坡内存存明显的垂直向下水流,但其在很大程度上受顺坡水流控制。与降雨对应,浅层地表(1—3m)存在压力脉冲,与低渗透性土体相比,其滞后过程很短,并且水流有瞬时水流的特征。斜坡在观察期问破坏,孔隙水压力的瞬时反应说明其为孔隙水压力型滑坡。 地下水流存在优势路径,这种现象可以解释在同样深度内一些传感器的异常反应。 展开更多
关键词 监测 孔隙水压力 粘土斜坡 滑坡 亚平宁山区
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The Calabrian Stage redefined
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作者 Maria Bianca Cita Luca Capraro +9 位作者 Neri Ciaranfi Enrico Di Stefano Fabrizio Lirer Patrizia Maiorano Maria Marino Isabella Raffi Domenico Rio Rodolfo Sprovieri Simona Stefanelli Gian Battista Vai 《Episodes》 SCIE 2008年第4期408-419,共12页
关键词 意大利 卡拉布里亚 地质学 地层
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A triplet of the only pulsation mode detected in the DAV star G132–12
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作者 Wen-Chao Su Jian-Ning Fu +5 位作者 Jian-Xing Chen Lester Fox-Machado Shi-Jie Zhao Carmen Ayala-Loera Jiang-Tao Wang Yang Pan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第6期276-280,共5页
Hydrogen atmosphere pulsating white dwarfs,also known as DAV stars,are the most abundant type of pulsating white dwarfs.High-temperature DAV stars in general exhibit a small number of pulsation modes and stable freque... Hydrogen atmosphere pulsating white dwarfs,also known as DAV stars,are the most abundant type of pulsating white dwarfs.High-temperature DAV stars in general exhibit a small number of pulsation modes and stable frequencies.G132-12 is one of the pulsating hydrogen atmosphere white dwarf stars which lies close to the blue edge of the instability strip.Previous researches reported that G132-12 might have only one pulsation mode with the period of 212.69 s.To study the pulsation properties of G132-12 in detail,we carried out a bi-site observation campaign in October 2019.Time series photometric data were collected during around 154 h in total.A Fourier analysis reveals three frequencies which are identified as the triplet of an l=1 g-mode pulsation with the period of 212.499 s.The rotational period is derived as Prot=35.0±6.7 h and the inclination of the rotational axis to the line of sight is 70°.G132-12 could be an ideal target for measuring the cooling scale of this white dwarf star with only one excited pulsation mode detected. 展开更多
关键词 white dwarfs OSCILLATIONS PHOTOMETRIC
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OPA1相关显性遗传视神经萎缩患者体内线粒体ATP产量不足
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作者 Lodi R. Tonon C. +1 位作者 Valentino M.L. 黄卫东 《世界核心医学期刊文摘(神经病学分册)》 2005年第4期12-12,共1页
Dominant optic atrophy has been associated with mutations in the OPA1 gene, which encodes for a dynamin- related GTPase, a mitochondrial protein implicated in the formation and maintenance of mitochondrial network and... Dominant optic atrophy has been associated with mutations in the OPA1 gene, which encodes for a dynamin- related GTPase, a mitochondrial protein implicated in the formation and maintenance of mitochondrial network and morphology. We used phosphorus magnetic resonance spectroscopy to assess calf muscle oxidative metabolism in six patients from two unrelated families carrying the c.2708- 2711delTTAG deletion in exon 27 of the OPA1 gene. The rate of postexercise phosphocreatine resynthesis, a measure of mitochondrial adenosine triphosphate production rate, was significantly delayed in the patients. Our in vivo results show for the first time to our knowledge a deficit of oxidative phosphorylation in OPA1- related DOA. 展开更多
关键词 视神经萎缩 ATP OPA1 显性遗传 合成速率 磷酸肌酸 在体研究 碱基缺失 氧化磷酸化 dynam
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Transcranial Direct Current Stimulation in ADHD:A Systematic Review of Efficacy,Safety,and Protocol-induced Electrical Field Modeling Results 被引量:4
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作者 Mohammad Ali Salehinejad Vahid Nejati +6 位作者 Mohsen Mosayebi-Samani Ali Mohammadi Miles Wischnewski Min-Fang Kuo Alessio Avenanti Carmelo M・Vicario Michael A.Nitsche 《Neuroscience Bulletin》 SCIE CAS CSCD 2020年第10期1191-1212,共22页
Transcranial direct current stimulation(tDCS)is a promising method for altering cortical excitability with clinical implications.It has been increasingly used in neurodevelopmental disorders,especially attention-defic... Transcranial direct current stimulation(tDCS)is a promising method for altering cortical excitability with clinical implications.It has been increasingly used in neurodevelopmental disorders,especially attention-deficit hyperactivity disorder(ADHD),but its efficacy(based on effect size calculations),safety,and stimulation parameters have not been systematically examined.In this systematic review,we aimed to(1)explore the effectiveness of tDCS on the clinical symptoms and neuropsychological deficits of ADHD patients,(2)evaluate the safety of tDCS application,especially in children with ADHD,(3)model the electrical field intensity in the target regions based on the commonly-applied and effective versus less-effective protocols,and(4)discuss and propose advanced tDCS parameters.Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses approach,a literature search identified 14 empirical experiments investigating tDCS effects in ADHD.Partial improving effects of tDCS on cognitive deficits(response inhibition,working memory,attention,and cognitive flexibility)or clinical symptoms(e.g.,impulsivity and inattention)are reported in10 studies.No serious adverse effects are reported in 747 sessions of tDCS.The left and right dorsolateral prefrontal cortex are the regions most often targeted,and anodal tDCS the protocol most often applied.An intensity of 2 mA induced stronger electrical fields than 1 mA in adults with ADHD and was associated with significant behavioral changes.In ADHD children,however,the electrical field induced by 1 mA,which is likely larger than the electrical field induced by 1 mA in adults due to the smaller head size of children,was sufficient to result in significant behavioral change.Overall,tDCS seems to be a promising method for improving ADHD deficits.However,the clinical utility of tDCS in ADHD cannot yet be concluded and requires further systematic investigation in larger sample sizes.Cortical regions involved in ADHD pathophysiology,stimulation parameters(e.g.intensity,duration,polarity,and electrode size),and types of symptom/deficit are potential determinants of tDCS efficacy in ADHD.Developmental aspects of tDCS in childhood ADHD should be considered as well. 展开更多
关键词 Transcranial direct current stimulation Attention-deficit hyperactivity disorder Dorsolateral prefrontal cortex Executive function Systematic review Brain modeling Non-invasive brain stimulation PEDIATRIC
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Evaluation of the potential exposure of butterflies to genetically modified maize pollen in protected areas in Italy
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作者 Salvatore Arpaia Ferdinando Baldacchino +5 位作者 Sara Bosi Giovanni Burgio Simona Errico Rosaria Alessandra Magarelli Antonio Masetti Salvatore Santorsola 《Insect Science》 SCIE CAS CSCD 2018年第4期549-561,共13页
Environmental impacts of genetically modified crops are mandatorily assessed during their premarket phase. One of the areas of concern is the possible impact on nontar- get organisms. Crops expressing Cry toxins might... Environmental impacts of genetically modified crops are mandatorily assessed during their premarket phase. One of the areas of concern is the possible impact on nontar- get organisms. Crops expressing Cry toxins might affect Lepidoptera larvae living outside cultivated fields, through pollen deposition on wild plants, which constitute their food source. While pollen toxicity varies among different events, possible exposure ofnontarget species depends on the agro-environmental conditions. This study was conducted in two protected areas in Italy, characterized by different climatic conditions, where many Lepi- doptera species thrive in proximity to maize cultivations. To estimate the possible exposure in absence of the actual stressor (e.g., Cryl-expressing maize plants), we conducted a two-year field survey of butterflies and weeds. Indicator species were selected--Aglais (Inachis) io in the Northern site and Vanessa cardui in the Southern site--and their phe- nology was investigated. Pollen dispersal from maize fields was measured by collection in Petri dishes. Duration and frequency of exposure was defined by the overlap between pollen emission and presence of larvae on host plants. Different risk scenarios are expected in the two regions: highest exposure is foreseen forA. io in the Northern site, while minimal exposure is estimated for V. cardui in the Southern site. In the latter case, locally grown maize cultivars flower in mid-summer in coincidence with an aestivation period for several butterfly species due to hot and dry conditions. Moreover, host plants of V. cardui are at the end of their life cycle thus limiting food availability. 展开更多
关键词 environmental risk assessment exposure assessment genetically modified plants LEPIDOPTERA nontarget organisms receiving environment
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A NEW APPROXIMATION ALGORITHM FOR THE MATCHING DISTANCE IN MULTIDIMENSIONAL PERSISTENCE
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作者 Andrea Cerri Patrizio Frosini 《Journal of Computational Mathematics》 SCIE CSCD 2020年第2期291-309,共19页
Topological Persistence has proven to be a promising framework for dealing with problems concerning shape analysis and comparison.In this contexts,it was originally introduced by taking into account 1-dimensional prop... Topological Persistence has proven to be a promising framework for dealing with problems concerning shape analysis and comparison.In this contexts,it was originally introduced by taking into account 1-dimensional properties of shapes,modeled by real-valued functions.More recently,Topological Persistence has been generalized to consider multidimensional proper ties of shapes,coded by vect or-valued functions.This extension has led to int roduce suitable shape descrip tors,named the multidimensional persis tence Betti numbers functions,and a distance to compare them,the so-called multidimensional matching distance.In this paper we propose a new computational framework to deal with the multidimensional matching distance.We start by proving some new theoretical results,and then we use them to formulate an algorithm for computing such a distance up to an arbitrary threshold error. 展开更多
关键词 Multidimensional persistent topology Matching distance Shape comparison.
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Nickel Catalyzed Functionalization of Allenes 被引量:8
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作者 Yang Liu Marco Bandini 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2019年第5期431-441,共11页
What is the most favorite and original chemistry developed in your research group?The stereoselective gold catalyzed manipulation of in doles with n-alcohols.How do you get into this specific field? Could you please s... What is the most favorite and original chemistry developed in your research group?The stereoselective gold catalyzed manipulation of in doles with n-alcohols.How do you get into this specific field? Could you please share some experiences with our readers?Step-by-step. Specifically, by merging our background on catalytic alkylation of arenes with an emerging area (at that time) such as homogeneous gold catalysis.What is the most important personality for a researcher?? Leadership, attitude in motivating early-stage scientists and capability of combining scientific inputs of different heritage for a single and ultimate goal. 展开更多
关键词 FAVORITE CHEMISTRY GOAL
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Recent Advances in the Catalytic Functionalization of “Electrophilic” Indoles 被引量:6
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作者 Alessandro Cerveri Marco Bandini 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2020年第3期287-294,共8页
When "dark"is bright:the scarcely explored electrophilic profile of the indolyl core(dark side)continues to inspire developments in organic synthesis by means of new catalytic methodologies.Recent advancemen... When "dark"is bright:the scarcely explored electrophilic profile of the indolyl core(dark side)continues to inspire developments in organic synthesis by means of new catalytic methodologies.Recent advancements in the field enabled molecular diversity and complexity to be effectively realized within heterocyclic chemistry. 展开更多
关键词 chemistry. CATALYTIC HETEROCYCLIC
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The HEPD particle detector of the CSES satellite mission for investigating seismo-associated perturbations of the Van Allen belts 被引量:6
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作者 AMBROSI Giovanni BARTOCCI Simona +39 位作者 BASARA Laurent BATTISTON Roberto BURGER William J. CARFORA Luca CASTELLINI Guido CIPOLLONE Piero CONTI Livio CONTIN Andrea DE DONATO Cinzia DE SANTIS Cristian FOLLEGA Francesco M. GUANDALINI Cristina IONICA Maria IUPPA Roberto LAURENTI Giuliano LAZZIZZERA Ignazio LOLLI Mauro MANEA Christian MARCELLI Laura MASCIANTONIO Giuseppe MERGE Matteo OSTERIA Giuseppe PACINI Lorenzo PALMA Francesco PALMONARI Federico PANICO Beatrice PATRIZII Laura PERFETTO Francesco PICOZZA Piergiorgio POZZATO Michele PUEL Matteo RASHEVSKAYA Irina RICCI Ester RICCI Marco RICCIARINI Sergio Bruno SCOTTI Valentina SOTGIU Alessando SPARVOLI Roberta SPATARO Bruno VITALE Vincenzo 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2018年第5期643-652,共10页
CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle envi... CSES(China Seismo-Electromagnetic Satellite) is a mission developed by CNSA(Chinese National Space Administration) and ASI(Italian Space Agency), to investigate the near-Earth electromagnetic, plasma and particle environment, for studying the seismo-associated disturbances in the ionosphere-magnetosphere transition zone. The anthropogenic and electromagnetic noise,as well as the natural non-seismic electromagnetic emissions is mainly due to tropospheric activity. In particular, the mission aims to confirming the existence of possible temporal correlations between the occurrence of earthquakes for medium and strong magnitude and the observation in space of electromagnetic perturbations, plasma variations and precipitation of bursts with highenergy charged particles from the inner Van Allen belt. In this framework, the high energy particle detector(HEPD) of the CSES mission has been developed by the Italian LIMADOU Collaboration. HEPD is an advanced detector based on a tower of scintillators and a silicon tracker that provides good energy and angular resolution and a wide angular acceptance, for electrons of 3–100 Me V, protons of 30–200 Me V and light nuclei up to the oxygen. CSES satellite has been launched on February 2^(nd), 2018 from the Jiuquan Satellite Launch Center(China). 展开更多
关键词 卫星发射中心 粒子 带子 空间管理 合作开发 空间机构 轻原子核 意大利
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Stormwater treatment: examples of computational fluid dynamics modeling
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作者 Gaoxiang YING John SANSALONE +4 位作者 Srikanth PATHAPATI Giuseppina GAROFALO Marco MAGLIONICO Andrea BOLOGNESI Alessandro ARTINA 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2012年第5期638-648,共11页
Control of rainfall-runoff particulate matter (PM) and PM-bound chemical loads is challenging; in part due to the wide gradation of PM complex geometries of many unit operations and variable flow rates. Such challen... Control of rainfall-runoff particulate matter (PM) and PM-bound chemical loads is challenging; in part due to the wide gradation of PM complex geometries of many unit operations and variable flow rates. Such challenges and the expense associated with resolving such challenges have led to the relatively common examination of a spectrum of unit operations and processes. This study applies the principles of computa- tional fluid dynamics (CFD) to predict the particle and pollutant clarification behavior of these systems subject to dilute multiphase flows, typical of rainfall-runoff, within computationally reasonable limits, to a scientifically acceptable degree of accuracy. The Navier-Stokes (NS) system of nonlinear partial differential equations for multi- phase hydrodynamics and separation of entrained particles are solved numerically over the unit operation control volume with the boundary and initial conditions defined and then solved numerically until the desired convergence criteria are met. Flow rates examined are scaled based on sizing of common unit operations such as hydrodynamic separators (HS), wet basins, or filters, and are examined from 1 to 100 percent of the system maximum hydraulic operating flow rate. A standard turbulence model is used to resolve flow, and a discrete phase model (DPM) is utilized to examine the particle clarification response. CFD results closely follow physical model results across the entire range of flow rates. Post-processing the CFD predictions provides an in-depth insight into the mechanistic behavior of unit operations by means of three dimensional (3-D) hydraulic profiles and particle trajectories. Results demon- strate the role of scour in the rapid degradation of unit operations that are not maintained. Comparisons are provided between measured and CFD modeled results and a mass balance error is identified. CFD is arguably the most powerful tool available for our profession since continuous simulation modeling. 展开更多
关键词 STORMWATER unit operations and processes(UOPs) hydrodynamic separation filtration adsorption computational fluid dynamics (CFD) turbulence modeling discrete phase model particle separation detention/reten-tion basins CLARIFICATION
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DATA REDUCTION OF SNAPSHOT VLBI OBSERVATIONS
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作者 南仁东 R.T.SCHILIZZI +2 位作者 C. R.FANTI 邓杰 《Science China Mathematics》 SCIE 1991年第5期590-597,共8页
Data reduction techniques have been developed for generating images of radio sourcesfrom snapshot very long baseline interferometry (VLBI) observations with poor u-v coverage.The reliability of the radio source struct... Data reduction techniques have been developed for generating images of radio sourcesfrom snapshot very long baseline interferometry (VLBI) observations with poor u-v coverage.The reliability of the radio source structures is discussed. Reference is made to 3C48, observedat 50 cm with a global array in a snapshot mode. 展开更多
关键词 VLBI CSS SNAPSHOT observation.
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Sensitivity of a solid Eu(Ⅲ) complex towards acetonitrile vapor:Structural and spectroscopic characterization
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作者 Fabio Piccinelli Veronica Paterlini +1 位作者 Magda Monari Marco Bettinelli 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第5期571-576,共6页
The Eu(Ⅲ)nitrate complex of the meso-N,N’-bis(2-pyridylmethylene)-1,2-(R,S)-cyclohexanediamine ligand was synthesized and characterized by single crystal and powder X-ray diffraction.The crystal lattice of the compl... The Eu(Ⅲ)nitrate complex of the meso-N,N’-bis(2-pyridylmethylene)-1,2-(R,S)-cyclohexanediamine ligand was synthesized and characterized by single crystal and powder X-ray diffraction.The crystal lattice of the complex is capable of absorbing and desorbing selectively acetonitrile molecules,at 293 K upon an acetonitrile vapor pressure of^0.1×10^5 Pa.This process,which is partially reversible,can be easily followed by both powder X-ray diffraction(P-XRD)and Eu(III)luminescence spectroscopy.The acetonitrile molecule,located in the outer coordination sphere of the metal ion,does not affect the radiative transition probability of 5 D0 level of Eu(Ⅲ)and also it does not activate further non-radiative channels from this level.On the other hand,this molecule is capable of affecting the energy position and intensities of the crystal field components of the 5 D0→7 F2 transition.The complex in solid form can be considered a promising material for the optical sensing of acetonitrile vapors. 展开更多
关键词 Eu(Ⅲ) X-ray diffraction Crystal structure Luminescence spectroscopy Rare earths
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Compact n-Manifolds via(n+l)-Colored Graphs:a New Approach
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作者 Luigi Grasselli Michele Mulazzani 《Algebra Colloquium》 SCIE CSCD 2020年第1期95-120,共26页
We introduce a representation via(n+l)-colored graphs of compact n-manifolds with(possibly empty)boundary,which appears to be very convenient for computer aided study and tabulation.Our construction is a generalizatio... We introduce a representation via(n+l)-colored graphs of compact n-manifolds with(possibly empty)boundary,which appears to be very convenient for computer aided study and tabulation.Our construction is a generalization to arbitrary dimension of the one recently given by Cristofori and Mulazzani in dimension three,and it is dual to the one given by Pezzana in the 1970s.In this context we establish some results concerning the topology of the represented manifolds:suspensions,fundamental groups,connected sums and moves between graphs representing the same manifold.Classification results of compact orientable 4-manifolds representable by graphs up to six vertices are obtained,together with some properties of the G-degree of 5-colored graphs relating this approach to tensor models theory. 展开更多
关键词 compact manifolds colored graphs fundamental groups dipole moves
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