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Data-driven Simulations of Magnetic Field Evolution in Active Region 11429:Magneto-frictional Method Using PENCIL CODE
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作者 P.Vemareddy Jorn Warnecke Ph.A.Bourdin 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期74-82,共9页
Coronal magnetic fields evolve quasi-statically over long timescales and dynamically over short timescales.As of now there exist no regular measurements of coronal magnetic fields,and therefore generating the coronal ... Coronal magnetic fields evolve quasi-statically over long timescales and dynamically over short timescales.As of now there exist no regular measurements of coronal magnetic fields,and therefore generating the coronal magnetic field evolution using observations of the magnetic field at the photosphere is a fundamental requirement to understanding the origin of transient phenomena from solar active regions(ARs).Using the magneto-friction(MF)approach,we aim to simulate the coronal field evolution in the solar AR 11429.The MF method is implemented in the open source PENCIL CODE along with a driver module to drive the initial field with different boundary conditions prescribed from observed vector magnetic fields at the photosphere.In order to work with vector potential and the observations,we prescribe three types of bottom boundary drivers with varying free-magnetic energy.The MF simulation reproduces the magnetic structure,which better matches the sigmoidal morphology exhibited by Atmospheric Imaging Assembly(AIA)images at the pre-eruptive time.We found that the already sheared field further driven by the sheared magnetic field will maintain and further build the highly sheared coronal magnetic configuration,as seen in AR 11429.Data-driven MF simulation is a viable tool to generate the coronal magnetic field evolution,capturing the formation of the twisted flux rope and its eruption. 展开更多
关键词 SUN corona-Sun evolution-Sun magnetic fields-Sun photosphere
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Chronic effects of stretching on range of motion with consideration of potential moderating variables:A systematic review with meta-analysis 被引量:1
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作者 Andreas Konrad Shahab Alizadeh +7 位作者 Abdolhamid Daneshjoo Saman Hadjizadeh Anvar Andrew Graham Ali Zahiri Reza Goudini Chris Edwards Carina Scharf David George Behm 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期186-194,共9页
Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence... Background:It is well known that stretch training can induce prolonged increases in joint range of motion(ROM).However,to date more information is needed regarding which training variables might have greater influence on improvements in flexibility.Thus,the purpose of this metaanalysis was to investigate the effects of stretch training on ROM in healthy participants by considering potential moderating variables,such as stretching technique,intensity,duration,frequency,and muscles stretched,as well as sex-specific,age-specific,and/or trained state-specific adaptations to stretch training.Methods:We searched through PubMed,Scopus,Web of Science,and SportDiscus to find eligible studies and,finally,assessed the results from 77 studies and 186 effect sizes by applying a random-effect meta-analysis.Moreover,by applying a mixed-effect model,we performed the respective subgroup analyses.To find potential relationships between stretch duration or age and effect sizes,we performed a meta-regression.Results:We found a significant overall effect,indicating that stretch training can increase ROM with a moderate effect compared to the controls(effect size=-1.002;Z=-12.074;95%confidence interval:-1.165 to-0.840;p<0.001;I^(2)=74.97).Subgroup analysis showed a significant difference between the stretching techniques(p=0.01)indicating that proprioceptive neuromuscular facilitation and static stretching produced greater ROM than did ballistic/dynamic stretching.Moreover,there was a significant effect between the sexes(p=0.04),indicating that females showed higher gains in ROM compared to males.However,further moderating analysis showed no significant relation or difference.Conclusion:When the goal is to maximize ROM in the long term,proprioceptive neuromuscular facilitation or static stretching,rather than ballistic/dynamic stretching,should be applied.Something to consider in future research as well as sports practice is that neither volume,intensity,nor frequency of stretching were found to play a significant role in ROM yields. 展开更多
关键词 FLEXIBILITY Long-term stretching Stretch training
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Geology of the Copper Mineralization in Proterozoic Ajabgarh Meta-Sediments of, Dokan-Dariba Belt, Sikar District Rajasthan Northwestern India
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作者 Rajendra Kumar Sharma 《Open Journal of Geology》 CAS 2023年第5期384-430,共47页
The Khetri copper belt is a well-known metallotect in northern part of Delhi fold belt in Rajasthan. On the eastern margin of the Khetri sub basin of North Delhi basin separated by a basement high, another sub basin A... The Khetri copper belt is a well-known metallotect in northern part of Delhi fold belt in Rajasthan. On the eastern margin of the Khetri sub basin of North Delhi basin separated by a basement high, another sub basin Alwar-Ajabgarh sub basin exposes that a thick sequence of Ajabgarh group of rocks overlies a thick arenaceous sequence of Alwar group of Delhi Super Group of rocks. The Ajabgarh meta sediments here in the Neem Ka thana area are characterized by presence of Bornite dominated copper mineralization with silver association and minor presence of Pb. The mineralization has been described by various workers as strata-bound, hypogene and IOCG. But these inferences are based on part information and the inference drawn is sectorial in nature. The current study includes a holistic study based on exploration over a period of more than two decades and the data generated suggest thereof, that this syngenetic sulphide mineralization associated with the sedimentation of marl and carbonate rocks. Subsequently it has been relocated during 2<sup>nd</sup> deformation accompanied by epigenetic component of mineralization depicted in terms of vein filled coarse grained aggregates of bornite and chalcopyrite disposed across the general disposition of litho-package. The EPMA and fluid inclusion data generated from the area indicate association of typical hydrothermal environment minerals like, Perkrite, Wittchenite, Aguilarite, Molybdnite etc. The mineralizing fluids have been trapped between the temperature ranges of 130°C to 375°C with average being 250°C to 300°C. The fluid salinity also varies from near pure hot water to moderately saline fluid indicative of multi-episodic mineralization of syngenetic nature coupled with epigenetic component. The ore textures indicate 500°C temperature range;certain intergrowths of minerals like specular hematite and bornite suggest the occurrence of hypogene environment induced due to emplacement of granite/pegmatite on the eastern and southern margins of the belt. The strata bound nature suggests the euxogenic environment facilitated by carbonate facies of rocks. The parallelism of sulphide with the rock fabric was attained during first deformation and the epigenetic component coupled with the hypogene assemblage was deposited during the D<sub>2</sub> deformation in the brittle ductile shear zones and limb shears, between the temperature ranges of 130°C to 570°C as deduced from petrochemical data. Hence a comprehensive model is suggested here on evolution of process of mineralization in the Neem Ka Thana belt. 展开更多
关键词 Proterozoic Copper Mineralization Ajabgarh Meta Sediments Dariba-Dokan Belt Neemka Thana. Northwestern India
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Ultra-high-field magnetic resonance:Why and when? 被引量:1
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作者 Ewald Moser 《World Journal of Radiology》 CAS 2010年第1期37-40,共4页
This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current li... This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current limitations are highlighted.Based on the first promising studies,potential clinical applications at 7 Tesla are suggested.Other aims are to stimulate awareness of the potential of ultra-high field magnetic resonance and to stimulate active participation in much needed basic or clinical research at 7 Tesla or higher. 展开更多
关键词 Alzheimer’s disease Brain tumors CARTILAGE Functional MAGNETIC RESONANCE imaging MAGNETIC RESONANCE MAGNETIC RESONANCE spectroscopy Multiple SCLEROSIS Ultra-high field MAGNETIC RESONANCE methods
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Creep Modeling of Magnesia-chromite Bricks in a RH Snorkel During a Process Cycle 被引量:2
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作者 JIN Shengli Harald HARMUTH +1 位作者 Dietmar GRUBER Roman RSSLER 《China's Refractories》 CAS 2015年第1期22-25,共4页
In this paper both experimental and analytical approaches to provide the inputs for creep modeling of refractories including a newly developed high temperature compressive creep machine and an inverse estimation proce... In this paper both experimental and analytical approaches to provide the inputs for creep modeling of refractories including a newly developed high temperature compressive creep machine and an inverse estimation procedure of creep law parameters are briefly introduced.Besides,a modified shear test is applied to determine the cohesion and friction angle of refractories under shear state. A RH snorkel equipped with magnesia- chromite bricks is chosen for a case study of thermomechanical simulation applying the classical creep model and Drucker-Prager creep model available in the finite element code ABAQUS,respectively. Afterwards,thermal stresses and joint opening of magnesia- chromite bricks during a process cycle are compared to distinguish the impact of these two creep models. 展开更多
关键词 creep shear failure thermomechanical modeling RH snorkel
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Characterisation of Submicron-Grain Sized Yttria-Stabilised Zirconia Electrolyte for SOFCs
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作者 Min Nah Tong Jon Binner +2 位作者 Christopher Munnings Bala Vaidhyanathan Hirad Taherparvar 《材料科学与工程(中英文版)》 2011年第2期177-183,共7页
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星载材料极弱剩磁测量方法研究
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作者 孟立飞 徐超群 +4 位作者 陈金刚 肖琦 刘超波 周斌 张铁龙 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2024年第8期1514-1519,共6页
为解决科学探测卫星星载材料微弱磁性测量难题,本文提出了一种卫星部件极弱剩磁的测量方法,并研制了测量系统。利用屏蔽技术去除外界磁场干扰,在屏蔽系统内搭建了测量系统,使用零场原子磁力仪采集旋转试件的磁场频谱信息,通过小波多分... 为解决科学探测卫星星载材料微弱磁性测量难题,本文提出了一种卫星部件极弱剩磁的测量方法,并研制了测量系统。利用屏蔽技术去除外界磁场干扰,在屏蔽系统内搭建了测量系统,使用零场原子磁力仪采集旋转试件的磁场频谱信息,通过小波多分辨分析方法处理得到试件的磁特征数据。研究表明:本文方法可有效提取极弱剩磁信号,且系统稳定度优于1×10^(-12) T/30 min,磁场分辨率优于1×10^(-12) T,磁矩提取分辨量级可达10^(-6) A·m^(2),为整星磁洁净控制和空间磁场高精度探测提供了途径。 展开更多
关键词 卫星 材料 极弱剩磁 磁屏蔽 测量系统 频谱 小波多分辨分析 磁洁净
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黄河流域煤炭-煤电-煤化工场地特征精准智能识别方法及应用
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作者 董霁红 王立兵 +4 位作者 冯晓彤 王蕾 刘峰 翟文 THOMAS Kienberger 《煤炭学报》 EI CAS CSCD 北大核心 2024年第2期1011-1024,共14页
黄河流域是“能源流域”,兼具生态环境治理和经济社会发展的重任,涉煤产业场地类型、数量及特征的精准智能识别是流域能源资源-低碳发展-生态保护的关键基础问题。研究融合多源数据与深度学习算法,从流域-基地-场地尺度对黄河流域13个... 黄河流域是“能源流域”,兼具生态环境治理和经济社会发展的重任,涉煤产业场地类型、数量及特征的精准智能识别是流域能源资源-低碳发展-生态保护的关键基础问题。研究融合多源数据与深度学习算法,从流域-基地-场地尺度对黄河流域13个大型煤电基地的煤基场地特征精准解析,获得煤电基地高精度、高质量的本底信息,提出一种实时实景智能识别涉煤产业空间特征的新方法。(1)筛选Google image、GF-6影像、Sentinel-2影像等多源数据,采集13个大型煤电基地煤基场地样本,构建煤炭场地(露天)、煤炭场地(井工)、煤电场地、煤化工场地4类数据集,涵盖21种样本类型。按照每种样本六面体设定6×10个样本,共计1 260个场地样本,分析得出最适样本数量-最高识别效率-最优识别模型的置信区间为80%~86%。(2)建立了煤基场地类型量化模型(Coal-based Site Classification Quantitative Model, CSCQM)和煤基场地范围特征模型(Coalbased Site Range Characteristic Model, CSRCM),模型平均精准度为0.837。明析了黄河流域涉煤产业场地本底信息,提出Google image底图叠加场地智能识别模型解算结果的高精度场地智能识别方法。(3)解析了流域神东煤炭-煤电产业集聚区精准本底数据,依据遥感生态指数(Remote Sensing Based Ecological Index,IRSE)分析,煤基场地分布2 km核心区地表生态质量受煤炭、煤电产业影响明显,5 km缓冲区则影响不明显,而8 km控制区基本不受煤炭、煤电产业影响,从而给出了“动态修复”与分区域、分阶段重点治理等低碳路径。(4)解析了流域宁东煤炭-煤电-煤化工产业集聚区精准本底数据,2022年煤炭场地17.81 km^(2)、占比34.1%,煤化工场地22.3 km^(2)、占比42.6%,煤电场地12.2 km^(2)、占比23.3%,煤化工场地>煤炭场地>煤电场地。进而采用PSR(Pressure-State-Response)模型得到风险管控综合得分53.93分,较2003年提高了27.2%。划分生态维护区、生产监测预警区、损毁修复重建区、其他调控区的分区管控模式。研究为涉煤产业煤基场地潜在污染控制、场地治理及区域生态修复提供技术方法与实践支撑。 展开更多
关键词 黄河流域 煤基场地 多源数据 AI模型 精准智能识别
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核技术在农业上应用现状和展望 被引量:3
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作者 梁劬 高美须 《核农学报》 CAS CSCD 北大核心 2024年第1期1-10,共10页
近二十年来,核技术应用已经融入农业科学研究和农业生产实践的各个方面,在某些领域是唯一和不可替代的技术手段。该综述全面概述了目前全世界核技术在农业主要领域应用的最新进展及其主要成就。着重介绍了核技术在动物生产和健康、食品... 近二十年来,核技术应用已经融入农业科学研究和农业生产实践的各个方面,在某些领域是唯一和不可替代的技术手段。该综述全面概述了目前全世界核技术在农业主要领域应用的最新进展及其主要成就。着重介绍了核技术在动物生产和健康、食品安全及控制、植物诱变育种和遗传、水土管理及农业环境以及害虫防治等领域的应用现状和创新发展趋势。针对世界农业所面临的诸多全球性严峻挑战,作者探讨并展示了核技术在农业上的应用前景及其优先发展的战略方向。 展开更多
关键词 核技术 同位素 辐照 昆虫不育 农业
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一种高精度星载磁强计系统级标定方法
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作者 孟立飞 徐超群 +5 位作者 肖琦 刘超波 耿晓磊 陈德祥 易忠 张铁龙 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第3期174-179,共6页
星载三轴磁强计经常被用于卫星在轨的姿态确认与修正,为提高其在轨磁场测量精度,提出了一种高精度的星载磁强计系统级标定方法。首先,引入了光学棱镜基准,完成了参照磁强计磁轴的正交性自校准。随后,利用二乘法完成了三轴零磁环境模拟... 星载三轴磁强计经常被用于卫星在轨的姿态确认与修正,为提高其在轨磁场测量精度,提出了一种高精度的星载磁强计系统级标定方法。首先,引入了光学棱镜基准,完成了参照磁强计磁轴的正交性自校准。随后,利用二乘法完成了三轴零磁环境模拟系统线圈系数校准,再利用参照磁强计完成了三轴零磁环境模拟系统磁轴正交性标定,从而获得高精度的空间磁环境地面模拟系统。最后,利用三轴零磁环境模拟系统与卫星正交性对应关系,完成了星载磁强计的标定。试验结果表明:经过标定后,三轴零磁环境模拟系统非正交度优于0.01°,星载磁强计标定误差优于10 nT,为星载磁强计系统地面标定试验验证提供了新途径。 展开更多
关键词 卫星控制 姿态确定 磁强计 自校准装置 棱镜
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一种高磁洁净卫星磁性建模与仿真计算方法
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作者 孟立飞 陈金刚 +3 位作者 肖琦 张琼予 邓佳欣 张铁龙 《航天器环境工程》 CSCD 2024年第3期296-300,共5页
卫星的磁洁净度是影响空间磁场测量精度的关键因素之一。为了在设计阶段预估“张衡一号”卫星的磁洁净度,文章提出一种基于单机多磁偶极子模型的卫星磁性建模与仿真计算方法:首先通过单机磁场测量数据构建单机多磁偶极子模型;然后根据... 卫星的磁洁净度是影响空间磁场测量精度的关键因素之一。为了在设计阶段预估“张衡一号”卫星的磁洁净度,文章提出一种基于单机多磁偶极子模型的卫星磁性建模与仿真计算方法:首先通过单机磁场测量数据构建单机多磁偶极子模型;然后根据单机的安装位置和方向组合成整星磁性模型;进而仿真计算卫星绝对磁场校准装置位置处的磁场。整星磁试验验证结果表明,该仿真方法可信有效,可应用于同类高磁洁净卫星的磁性建模与仿真计算。 展开更多
关键词 “张衡一号”卫星 磁性建模 磁性仿真 多磁偶极子模型 空间磁场探测
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Targeting KRAS in pancreatic cancer
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作者 SANDRA STICKLER BARBARA RATH GERHARD HAMILTON 《Oncology Research》 SCIE 2024年第5期799-805,共7页
Pancreatic cancer has a dismal prognosis due to late detection and lack of efficient therapies.The Kirsten rat sarcoma virus(KRAS)oncogene is mutated in up to 90%of all pancreatic ductal adenocarcinomas(PDACs)and cons... Pancreatic cancer has a dismal prognosis due to late detection and lack of efficient therapies.The Kirsten rat sarcoma virus(KRAS)oncogene is mutated in up to 90%of all pancreatic ductal adenocarcinomas(PDACs)and constitutes an attractive target for therapy.However,the most common KRAS mutations in PDAC are G12D(44%),G12V(34%)and G12R(20%)that are not amenable to treatment by KRAS G12C-directed cysteine-reactive KRAS inhibitors such as Sotorasib and Adagrasib that exhibit clinical efficacy in lung cancer.KRAS G12C mutant pancreatic cancer has been treated with Sotorasib but this mutation is detected only in 2%–3%of PDAC.Recently,the KRAS G12D-directed MRTX1133 inhibitor has entered clinical trials and more of such inhibitors are in development.The other KRAS mutations may be targeted indirectly via inhibition of the cognate guanosine exchange factor(GEF)Son of Sevenless 1 that drives KRAS.These agents seem to provide the means to target the most frequent KRAS mutations in PDAC and to improve patient outcomes. 展开更多
关键词 Pancreatic cancer PDAC KRAS SOS1 PROTAC
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The Soft X-ray Imager(SXI)on the SMILE Mission 被引量:4
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作者 S.Sembay A.L.Alme +83 位作者 D.Agnolon T.Arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin G.Branduardi-Raymont T.Crawford J.P.Breuer T.Buggey G.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Crawford N.Eaton C.Feldman C.Forsyth T.Frantzen G.Galgóczi J.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer M.Guedel Y.Guo M.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland S-Y.Hsieh M.W.J.Hubbard H.Jeszenszky M.Jones T.Kennedy K.Koch-Mehrin S.Kögl S.Krucker K.D.Kuntz C.Lakin G.Laky O.Lylund A.Martindale J.Miguel Mas Hesse R.Nakamura K.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel J.Pearson G.Peikert F.S.Porter T.Pouliantis B.H.Qureshi W.Raab G.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman S.Sachdev A.Samsonov M.Soman D.Sibeck S.Smit J.Søndergaard R.Speight S.Stavland M.Steller TianRan Sun J.Thornhill W.Thomas K.Ullaland B.Walsh D.Walton C.Wang S.Yang 《Earth and Planetary Physics》 EI CSCD 2024年第1期5-14,共10页
The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission.SMILE is a joint science mission between the European Space Agency(ESA)and the Chinese... The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission.SMILE is a joint science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in 2025.SXI is a compact X-ray telescope with a wide field-of-view(FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE orbit.SXI is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s exosphere.SWCX provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field lines.The sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many hours.SXI is led by the University of Leicester in the United Kingdom(UK)with collaborating organisations on hardware,software and science support within the UK,Europe,China and the United States. 展开更多
关键词 Soft X-ray Imaging micropore optics large area CCD
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Recent advancements in thermal conductivity of magnesium alloys
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作者 Hao Lv Jun Tan +7 位作者 Qian Yuan Fanglei Wang Yunxuan Zhou Quan Dong Aitao Tang Jürgen Eckert Bin Jiang Fusheng Pan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1687-1708,共22页
As highly integrated circuits continue to advance,accompanied by a growing demand for energy efficiency and weight reduction,materials are confronted with mounting challenges pertaining to thermal conductivity and lig... As highly integrated circuits continue to advance,accompanied by a growing demand for energy efficiency and weight reduction,materials are confronted with mounting challenges pertaining to thermal conductivity and lightweight properties.By virtue of numerous intrinsic mechanisms,as a result,the thermal conductivity and mechanical properties of the Mg alloys are often inversely related,which becomes a bottleneck limiting the application of Mg alloys.Based on several effective modification methods to improve the thermal conductivity of Mg alloys,this paper describes the law of how they affect the mechanical properties,and clearly indicates that peak aging treatment is one of the best ways to simultaneously enhance an alloy's thermal conductivity and mechanical properties.As the most frequently used Mg alloy,cast alloys exhibit substantial potential for achieving high thermal conductivity.Moreover,recent reports indicate that hot deformation can significantly improve the mechanical properties while maintaining,and potentially slightly enhancing,the alloy's thermal conductivity.This presents a meaningful way to develop Mg alloys for applications in the field of small-volume heat dissipation components that require high strength.This comprehensive review begins by outlining standard testing and prediction methods,followed by the theoretical models used to predict thermal conductivity,and then explores the primary influencing factors affecting thermal conductivity.The review summarizes the current development status of Mg alloys,focusing on the quest for alloys that offer both high thermal conductivity and high strength.It concludes by providing insights into forthcoming prospects and challenges within this field. 展开更多
关键词 Mg alloy Thermal conductivity Mechanical properties Solute atom Second phase
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Diagenetic history and porosity evolution of the Middle Permian clastic-carbonate mixed system,Indus Basin,Pakistan:Implications for reservoir development
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作者 Bilal Wadood Suleman Khan +4 位作者 Michael Wagreich Torsten Vennemann Hong Li Matee Ullah Katerina Schöpfer 《Energy Geoscience》 EI 2024年第4期156-173,共18页
This study deals with unraveling the diagenesis-induced porosity evolution in a mixed clastic-carbonate sequence of the Middle Permian Indus Basin,Pakistan.Multiple data sets including outcrop,petrography,cathodolumin... This study deals with unraveling the diagenesis-induced porosity evolution in a mixed clastic-carbonate sequence of the Middle Permian Indus Basin,Pakistan.Multiple data sets including outcrop,petrography,cathodoluminescence,scanning electron microscopy(SEM),mineralogy,and geochemical isotopic compositions were integrated to establish a link between porosity evolution and diagenesis.The spatial thickness and facies variations of the strata at outcrop scale are inherently controlled by the underlying bathymetry of the basin with deepening westward trend.The low values ofδ^(18)O of the target strata,relative to average values of the Permian carbonate,hints to diagenetic alteration in the strata.The data sets used in this study reveal modification of the strata in four environments,that is,i)early marine diagenesis indicated by micritization,pervasive dolomitization and isopachous fibrous cements,followed by ii)meteoric dissolution,and iii)shallow burial diagenetic processes including the precipitation of blocky cement,compaction of skeletal and non-skeletal allochems,and stylolites,and iv)a deep burial environment,characterized by pressure solution,and micro-fractures.The clastic intervals host subangular to subrounded quartz grains,floating textures,and almost complete absence of deleterious clay minerals,consequently resulting in the preservation of primary porosity.The primary porosity of carbonate intervals is preserved in the form of intercrystalline and intracrystalline porosity.The secondary porosity evolved through various diagenetic phases in the form of fractures and dissolution.The diagenetic solution mediated by organic matter in carbonates may have experienced both bacterial decomposition and thermochemical sulfate reduction,precipitating sulfides within the pores.The plug porosity/permeability analyses generally suggest high porosity in the siliciclastic unit,and carbonates with wackestone fabric while lower values were observed for the inner shelf pure carbonate facies.However,both intervals show very low permeability values probably due to isolated moldic pores and intense micritization.Therefore,clastic intervals may provide an opportunity to serve as a moderate reservoir;however,the carbonate intervals possess very low permeability values and could generally be considered as low-moderate reservoir potential. 展开更多
关键词 Reservoir DIAGENESIS POROSITY PERMIAN Indus Basin
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Training muscles to keep the aging brain fit
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作者 Johannes Burtscher Martin Burtscher 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第6期761-763,共3页
1.Aging and exercise Aging is associated with the decline of cellular,tissue,and systemic functions and is characterized by at least 7 highly interdependent molecular pillars of aging1(Fig.1).Besides compromised genet... 1.Aging and exercise Aging is associated with the decline of cellular,tissue,and systemic functions and is characterized by at least 7 highly interdependent molecular pillars of aging1(Fig.1).Besides compromised genetic functions(telomer shortening and epigenetic dysregulation),metabolic efficiency(impaired mitochondrial functions and nutrient sensing),and cellular stress responses deteriorate.Consequential disruption of normal protein regulation(proteostasis)in combination with impaired cellular waste clearance leads to the accumulation of macromolecular damage(and in some cases to specific protein aggregation pathologies,like in Alzheimer’s dementia brains). 展开更多
关键词 IMPAIRED AGING AGGREGATION
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Boron Nitride-Integrated Lithium Batteries:Exploring Innovations in Longevity and Performance
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作者 Shayan Angizi Sayed Ali Ahmad Alem +3 位作者 Mahdi Torabian Maryam Khalaj Dmitri Golberg Amir Pakdel 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第6期13-40,共28页
The current global warming,coupled with the growing demand for energy in our daily lives,necessitates the development of more efficient and reliable energy storage devices.Lithium batteries(LBs)are at the forefront of... The current global warming,coupled with the growing demand for energy in our daily lives,necessitates the development of more efficient and reliable energy storage devices.Lithium batteries(LBs)are at the forefront of emerging power sources addressing these challenges.Recent studies have shown that integrating hexagonal boron nitride(h-BN)nanomaterials into LBs enhances the safety,longevity,and electrochemical performance of all LB components,including electrodes,electrolytes,and separators,thereby suggesting their potential value in advancing eco-friendly energy solutions.This review provides an overview of the most recent applications of h-BN nanomaterials in LBs.It begins with an informative introduction to h-BN nanomaterials and their relevant properties in the context of LB applications.Subsequently,it addresses the challenges posed by h-BN and discusses existing strategies to overcome these limitations,offering valuable insights into the potential of BN nanomaterials.The review then proceeds to outline the functions of h-BN in LB components,emphasizing the molecular-level mechanisms responsible for performance improvements.Finally,the review concludes by presenting the current challenges and prospects of integrating h-BN nanomaterials into battery research. 展开更多
关键词 ELECTRODE ELECTROLYTE hexagonal boron nitride lithium battery SEPARATOR
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Phylogenetic insights resolve Dacampiaceae(Pleosporales)as polyphyletic:Didymocyrtis(Pleosporales,Phaeosphaeriaceae)with Phoma-like anamorphs resurrected and segregated from Polycoccum(Trypetheliales,Polycoccaceae fam.nov.) 被引量:3
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作者 Damien Ertz Paul Diederich +5 位作者 James D.Lawrey Franz Berger Colin E.Freebury Brian Coppins Alain Gardiennet Josef Hafellner 《Fungal Diversity》 SCIE 2015年第5期53-89,共37页
A phylogenetic analysis of nuLSU and ITS sequences representing genera previously included in Dacampiaceae indicates that the family is strongly polyphyletic and that the type species of Dacampia is placed in Pleospor... A phylogenetic analysis of nuLSU and ITS sequences representing genera previously included in Dacampiaceae indicates that the family is strongly polyphyletic and that the type species of Dacampia is placed in Pleosporales.The genus Munkovalsaria s.str.is placed in Didymosphaeriaceae(Pleosporales).Polycoccum s.str.and two species of Clypeococcum are shown to form a new lineage sister to the Trypetheliaceae in Trypetheliales and described here as Polycoccaceae.Other members of Polycoccum s.lat.are included in the Pleosporales and are closely related to lichenicolous Phoma-like species of the family Phaeosphaeriaceae.The genus Didymocyrtis is resurrected for these species and for lichenicolous species previously assigned to Diederichia,Diederichomyces,Leptosphaeria and Phoma.The genera Diederichia and Diederichomyces are synonymized with Didymocyrtis.The new combinations Didymocyrtis bryonthae,D.cladoniicola,D.foliaceiphila,D.infestans,D.kaernefeltii,D.melanelixiae,D.pseudeverniae,D.ramalinae,D.slaptoniensis and D.xanthomendozae are made,and the new name D.epiphyscia is introduced for Phoma physciicola.Some anamorph-teleomorph relationships are resolved,such as Didymocyrtis ramalinae–Phoma ficuzzae and Didymocyrtis consimilis–Phoma caloplacae,the phylogenetic results being supported by single ascospore cultures that lead to the asexual stage producing pycnidia and conidia in culture.Speciation by host switching is assumed to be important in the genus Didymocyrtis.An identification key to Didymocyrtis species is provided. 展开更多
关键词 DOTHIDEOMYCETES LEPTOSPHAERIA Diederichia Diederichomyces Lichenicolous fungi Phylogeny
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基于多偶极子磁性模型的卫星复杂磁场建模方法 被引量:2
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作者 孟立飞 肖琦 +4 位作者 王国强 陈金刚 易忠 吴明雨 张铁龙 《航天器环境工程》 CSCD 北大核心 2023年第4期356-360,共5页
飞行器、舰船和潜艇等典型可移动平台具有复杂的磁场,获取这些磁场信息对于提高磁场探测精度具有重要意义。文章在简要总结典型可移动平台复杂磁场的建模方法基础上,结合卫星自身特点,提出基于多偶极子磁性模型的卫星复杂磁场快速建模... 飞行器、舰船和潜艇等典型可移动平台具有复杂的磁场,获取这些磁场信息对于提高磁场探测精度具有重要意义。文章在简要总结典型可移动平台复杂磁场的建模方法基础上,结合卫星自身特点,提出基于多偶极子磁性模型的卫星复杂磁场快速建模方法。其技术途径有两种:一是基于单机磁试验数据建立单机磁性模型,再组合成整星多偶极子磁性模型;二是基于卫星磁试验数据直接建立整星多偶极子磁性模型。采用这两种技术途径完成某型号卫星的磁场建模、计算与测量验证,测试结果表明多偶极子法可很好地适用于磁洁净卫星复杂磁场的快速建模计算,精度优于0.2 nT。 展开更多
关键词 卫星 磁试验 磁场建模 多偶极子法
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不同前驱体对β″-Al_(2)O_(3)制备的影响 被引量:2
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作者 车洪生 张阳 +3 位作者 苏静波 石文启 陈留刚 金胜利 《中国有色冶金》 CAS 北大核心 2023年第2期67-72,共6页
钠硫电池是一种优异的电化学储能电源,β″-Al_(2)O_(3)电解质陶瓷是钠硫电池最为核心的材料,直接决定了钠硫电池的性能、生产工艺和成本。片状结构的勃姆石适宜作为制备层状β″-Al_(2)O_(3)的前驱体,本文分别以α-Al_(2)O_(3)、γ-Al_... 钠硫电池是一种优异的电化学储能电源,β″-Al_(2)O_(3)电解质陶瓷是钠硫电池最为核心的材料,直接决定了钠硫电池的性能、生产工艺和成本。片状结构的勃姆石适宜作为制备层状β″-Al_(2)O_(3)的前驱体,本文分别以α-Al_(2)O_(3)、γ-Al_(2)O_(3)和水热反应合成的勃姆石为铝源,NaHCO3为钠源,在1280℃制备了β″-Al_(2)O_(3)。试验过程中考察了不同前驱体对β″-Al_(2)O_(3)的影响,同时探究了不同钠源加入量和温度对制备β″-Al_(2)O_(3)的影响,并采用X射线衍射和扫描电子显微镜分析β″-Al_(2)O_(3)的物相组成和显微结构。结果表明:采用α-Al_(2)O_(3)和γ-Al_(2)O_(3)为前驱体制备的β″-Al_(2)O_(3)中还同时存在α-Al_(2)O_(3),而选取片状勃姆石为铝源,加入22%NaHCO_(3),在1280℃下煅烧,得到了纯相的β″-Al_(2)O_(3),呈1μm左右的片状结构,晶粒之间分散较好,没有团聚现象,是理想的β″-Al_(2)O_(3)前驱体。 展开更多
关键词 β″-Al_(2)O_(3) 勃姆石 氢氧化铝 水热合成 碳酸氢钠 钠硫电池 储能材料
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