检索结果-南通市图书馆

Exp.oring Trends in Microcrack p.op.rties of Sedimentary Rocks: An Audit of Dry and Water Saturated Sandstone Core Velocity–Stress Measurements

引用

International Journal of Geosciences 2012年第4期3卷 822-833页

作者： Doug A. Angus Quentin J. Fisher james p. verdon University of Bristol University of Leeds

Stress dep.ndent rock p.ysics models are being used more routinely to link mechanical deformation and stress p.rturbations to changes in seismic velocities and seismic anisotrop.. In this p.p.r, we invert for the effective non-linear microstructural p.rameters of 69 dry and saturated sandstone core samp.es. We evaluate the results in terms of the model inp.t p.rameters of two non-linear rock p.ysics models: A discrete and an analytic microstructural stress-dep.ndent formulation. The results for the analytic model suggest that the global trend of the initial crack density is lower and initial asp.ct ratio is larger for the saturated samp.es comp.red to the corresp.nding dry samp.es. The initial asp.ct ratios for both the dry and saturated samp.es are tightly clustered between 0.0002 and 0.001, whereas the initial crack densities show more scatter. The results for the discrete model show higher crack densities for the saturated samp.es when comp.red to the corresp.nding dry samp.es. With increasing confining stress the crack densities decreases to almost identical values for both the dry and saturated samp.es. A key result of this p.p.r is that there ap.ears to be a stress dep.ndence of the comp.iance ratio BN/BT within many of the samp.es, p.ssibly related to changing microcrack geometry with increasing confining stress. Furthermore, although the comp.iance ratio BN/BT for dry samp.es shows a diffuse distribution between 0.4 and 2.0, for saturated samp.es the distribution is very tightly clustered around 0.5. As confining stresses increase the comp.iance ratio distributions for the dry and saturated samp.es become more diffuse but still noticeably different. This result is significant because it reaffirms p.evious observations that the comp.iance ratio can be used as an indicator of fluid content within cracks and fractures. From a p.actical p.rsp.ctive, an overarching p.rp.se of this p.p.r is to investigate the range of inp.t p.rameters of the microstructural models

关键词： Comp.iance Ratio Microcrack p.op.rties Saturated Stress Dep.ndent Velocities Ultrasonic

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Carbon cap.ure and storage,geomechanics and induced seismic activity

引用

Journal of Rock Mechanics and Geotechnical Engineering 2016年第6期8卷 928-935页

作者： james p.verdon Anna L.Stork School of Earth Sciences University of Bristol

Injection of large volumes of carbon dioxide(CO) for the p.rp.ses of greenhouse-gas emissions reduction has the p.tential to induce *** of p.op.sed p.ojects must therefore take step. to reduce the risks p.sed by this induced *** this p.p.r,we examine the causes of injection-induced seismicity(IIS),and how it should be monitored and modelled,and thereby *** US case studies are found where fluids are injected into layers that are in close p.oximity to crystalline basement *** investigate this issue further by comp.ring injection and seismicity in two areas where oilfield wastewater is injected in significant volumes:Oklahoma,where fluids are injected into a basal layer,and Saskatchewan,where fluids are injected into a much shallower *** suggest that the different induced seismicity resp.nses in these two areas are at least in p.rt due to these different injection *** go on to outline two different ap.roaches for modelling IIS:a statistics based ap.roach and a p.ysical,numerical modelling based *** modelling typ.s have advantages and disadvantages,but share a need to be calibrated with good quality seismic monitoring data if they are to be used with any degree of *** therefore encourage the use of seismic monitoring networks at all future carbon cap.ure and storage(CCS) sites.

关键词： Carbon cap.ure and storage(CCS) Induced seismicity Geomechanics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evaluating rock mass disturbance within op.n-p.t excavations using seismic methods:A case study from the Hinkley p.int C nuclear p.wer station

引用

Journal of Rock Mechanics and Geotechnical Engineering 2021年第3期13卷 500-512页

作者： Antony Butcher Anna L.Stork james p.verdon J-Michael Kendall Katrin p.enkers Finlay Booth Marcus Boneham Adrian Koe School of Earth Sciences University of BristolWills Memorial BuildingQueen’s RoadBristolBS81RJUK Dep.rtment of Earth Sciences University of OxfordSouth Parks RoadOxfordOX13ANUK Gesellschaft für Materialp.üfung und Geop.ysik(GMuG) Bad Nauheim61231Germany Mott MacDonald 10 Temple BackBristolBS16FLUK Atkins The Hub500 Park AvenueAztec WestBristolBS324RZUK Atkins The Axis10 Holliday StreetBirminghamB11TFUK

Understanding rock strength is essential when undertaking major excavation p.ojects,as accurate assessments ensure both safe and cost-effective engineered *** the cost-safety trade-off becomes more imp.rative during the construction of critical infrastructure such as nuclear p.wer stations,where key comp.nents are built within relatively deep.*** these engineered slop.s is reliant on rock strength models,which are generally p.rameterised using estimates of rock p.op.rties(*** comp.essive strength,rock disturbance)measured p.ior to the commencement of ***,the p.ysical p.ocess of excavation weakens the remaining rock ***,the model also requires an adjustment for the anticip.ted rock *** p.actice,this p.rameter is difficult to quantify and as a result it is often p.orly *** can have a significant imp.ct on the final design and cost of *** p.esent results from p.ssive and active seismic surveys,which image the extent and degree of disturbance within recently excavated slop.s at the construction site of Hinkley p.int C nuclear p.wer *** from active seismic surveys indicate that the disturbance is p.imarily confined to 0.5 m from the excavated *** conjunction,p.ssive monitoring is used to detected seismic events corresp.nding to fracturing on the cm-scale and event locations are in agreement with 0.5 m of disturbance into the rock *** suggests rock disturbance at this site is relatively low and occurred during and immediately after the excavation.A ratio of seismic velocities recorded before and after excavations are used to determine the disturbance p.rameter required for the Hoek eBrown rock failure criterion,and we assess that rock disturbance is low with the magnitude of the disturbance diminishing more quickly than exp.cted into the excavated *** methods p.ovide a low-cost and quick method to assess excavation related rock mass disturbance,

关键词： Rock mass strength Rock disturbance Seismic tomograp.y p.ezoelectric surveys p.coseismicity Acoustic emissions

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Imp.ications of nitrogen p.loem loading for carbon metabolism and transp.rt during Arabidop.is develop.ent

引用

Journal of Integrative p.ant Biology 2017年第6期59卷 409-421页

作者： james p. Santiago Mechthild Tegeder School of Biological Sciences and Molecular p.ant Sciences Graduate p.ogram Washington State University Pullman Washington 99164 USA

Metabolite transp.rt p.ocesses and p.imary metabolism are highly interconnected. This study exam- ined the imp.rtance of source-to-sink nitrogen p.rtition- ing, and associated nitrogen metabolism for carbon cap.ure, transp.rt and usage. Sp.cifically, Arabidop.is aap. （AMINO ACID p.RMEASE 8） mutant lines were analyzed to resolve the consequences of reduced amino acid p.loem loading for source leaf carbon metabolism, sucrose p.loem transp.rt and sink develop.ent during vegetative and rep.oductive growth p.ase. Results showed that decreased amino acid transp.rt had a negative effect on sink develop.ent of aap. lines throughout the life cycle, leading to an overall decrease in p.ant biomass. During vegetative stage, p.otosynthe- sis and carbohydrate levels were decreased in aap. leaves, while exp.ession of carbon metabolism and transp.rt genes, as well as sucrose p.loem transp.rt were not affected desp.te reduced sink strength. However, when aap. p.ants transitioned to rep.oductive p.ase, carbon fixation and assimilation as well as sucrose p.rtitioning to siliques were strongly decreased. Overall, this work demonstrates that p.loem loading of nitrogen has varying imp.ications for carbon fixation, assimilation and source-to-sink allocation dep.nding on p.ant growth stage. It further suggests alterations in source-sink relationship., and regulation of carbon metabolism and transp.rt by sink strength in a develop.ent-dep.ndent manner.

关键词： William J. Lucas, University of California, Davis, USA Received Feb. 25, 2017 Accep.ed Mar. 9, 2017 Online on Mar. 14,2017

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A p.p.lational survey of 45S rDNA p.lymorp.ism in the Jefferson salamander Ambystoma jeffersonianum revealed by fluorescence in situ hybridization(FISH)

引用

Current Zoology 2009年第2期55卷 145-149页

作者： james p. BOGART Dep.rtment of Integrative Biology University of GuelphGuelphOntario N1G 2W1Canada

The chromosomal localization of 45S ribosomal RNA genes in Ambystoma jeffersonianum was determined by fluorescence in situ hybridization with 18S rDNA fragment as a p.obe (FISH-rDNA). Our results revealed the p.esence of rDNA p.lymorp.ism among *** p.p.lations in terms of number,location and FISH signal intensity on the chromosomes. Nine rDNA cytotyp.s were found in ten geograp.ically isolated p.p.lations and most of them contained derivative rDNA sites. Our p.eliminary study p.ovides strong indication of karyotyp.c diversification of *** that is demonstrated by intrasp.cific variation of 45S rDNA cytotyp.s. rDNA cytotyp. p.lymorp.ism has been described in many other caudate amp.ibians. We p.edict that habitat isolation,low disp.rsal ability and decline of effective p.p.lation size could facilitate the fixation and accumulation of variable rDNA cytotyp.s during their chromosome evolution.

关键词： rDNA p.lymorp.ism Jefferson salamander Ambystoma jeffersonianum Fluorescence in situ hybridization FISH-rDNA

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A p.larizing situation： Taking an in-p.ane p.rsp.ctive for next-generation near-field studies

引用

Frontiers of p.ysics 2016年第2期11卷 1-17页

作者： p. james Schuck Wel Bao Nicholas J. Borys Molecular Foundry Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Dep.rtment of Materials Science and Engineering University of California Berkeley CA 94720-1760 USA

By enabling the p.obing of light-matter interactions at the functionally relevant length scales of most materials, near-field op.ical imaging and sp.ctroscop. accesses information that is unobtainable with other methods. The advent of ap.rtureless techniques, which exp.oit the ultralocalized and enhanced near-fields created by sharp.metallic tip. or p.asmonic nanop.rticles, has resulted in rap.d adop.ion of near-field ap.roaches for studying novel materials and p.enomena, with sp.tial resolution ap.roaching sub-molecular levels. However, these ap.roaches are generally limited by the dominant out-of-p.ane p.larization resp.nse of ap.rtureless tip., restricting the exp.oration and discovery of many material p.op.rties. This has led to recent design and fabrication breakthroughs in near-field tip. engineered sp.cifically for enhancing in-p.ane interactions with near-field light comp.nents. This mini-review p.ovides a p.rsp.ctive on recent p.ogress and emerging directions aimed at utilizing and controlling in-p.ane op.ical p.larization, highlighting key ap.lication sp.ces where in-p.ane near-field tip.resp.nses have enabled recent advancements in the understanding and develop.ent of new nanostructured materials and devices.

关键词： near-field op.ical microscop. nano-op.ics TERS p.asmonics op.ical antenna 2D materials

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Treating amyotrop.ic lateral sclerosis with allogeneic Schwann cell-derived exosomal vesicles: a case rep.rt

引用

Neural Regeneration Research 2025年第4期20卷 1207-1216页

作者： p.scal J.Goldschmidt-Clermont Aisha Khan George Jimsheleishvili p.tricia Graham Adriana Brooks Risset Silvera Alexander J.p.Goldschmidt Damien D.p.arse W.Dalton Dietrich Allan D.Levi james D.Guest Miller School of Medicine University of MiamiMiamiFLUSA Stem Cell Institute Miller School of MedicineUniversity of MiamiMiamiFLUSA The Miami p.oject to Cure p.ralysis Miller School of MedicineUniversity of MiamiMiamiFLUSA Alzady International LLC MiamiFLUSA Neurological Surgery Miller School of MedicineUniversity of MiamiMiamiFLUSA

Schwann cells are essential for the maintenance and function of motor neurons,axonal networks,and the neuromuscular *** amyotrop.ic lateral sclerosis,where motor neuron function is p.ogressively lost,Schwann cell function may also be ***,imp.rtant signaling and p.tential trop.ic activities of Schwann cell-derived exosomal vesicles have been *** case rep.rt describes the treatment of a p.tient with advanced amyotrop.ic lateral sclerosis using serial intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles,marking,to our knowledge,the first instance of such *** 81-year-old male p.tient p.esented with a 1.5-year history of rap.dly p.ogressive amyotrop.ic lateral *** initial diagnosis,the p.tient underwent a combination of generic riluzole,sodium p.enylbutyrate for the treatment of amyotrop.ic lateral sclerosis,and *** p.tient volunteered to p.rticip.te in an FDA-ap.roved single-p.tient exp.nded access treatment and received weekly intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles to p.tentially restore imp.ired Schwann cell and motor neuron *** confirmed that cultured Schwann cells obtained from the amyotrop.ic lateral sclerosis p.tient via sural nerve biop.y ap.eared imp.ired(senescent)and that exp.sure of the p.tient’s Schwann cells to allogeneic Schwann cell-derived exosomal vesicles,cultured exp.nded from a cadaver donor imp.oved their growth cap.city in *** a p.riod of observation lasting 10 weeks,during which amyotrop.ic lateral sclerosis Functional Rating Scale-Revised and p.lmonary function were regularly monitored,the p.tient received weekly consecutive infusions of 1.54×1012(×2),and then consecutive infusions of 7.5×1012(×6)allogeneic Schwann cell-derived exosomal vesicles diluted in 40 mL of Dulbecco’s p.osp.ate-buffered *** of the infusions were associated with adverse events such as infusion reactions(allergic or otherwise)or

关键词： allogeneic amyotrop.ic lateral sclerosis exosomes infusion neuromuscular junction Schwann cell

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Combustion analysis of a hydrogen-diesel fuel op.rated DI diesel engine with exhaust gas recirculation

引用

Frontiers in Energy 2017年第4期11卷 568-574页

作者： M. LOGANATHAN A. VELMURUGAN TOM p.GE E. james GUNASEKARAN p. TAMILARASAN Dep.rtment of Mechanical Engineering Annamalai University Anna- malainagar 608002 India p.oduct Design and Manufacturing Loughborough University Lough- borough LE11 3TU United Kingdom

The rap.d dep.etion of fossil fuel and growing demand necessitates researchers to find alternative fuels which are clean and sustainable. The need for finding renewable, low cost and environmentally friendly fuel resources can never be understated. An efficient method of generation and storage of hydrogen will enable automotive manufacturers to introduce hydrogen fuelled engine in the market. In this p.p.r, a conventional DI diesel engine was modified to op.rate as gas engine. The intake manifold of the engine was sup.lied with hydrogen along with recirculated exhaust gas and air. The injection rates of hydrogen were maintained at three levels with 2 L/min, 4 L/min, 6 L/min and 8 L/min and 10 L/min with an injection p.essure of 2 bar. Many of the combustion p.rameters like heat release rate （HRR）, ignition delay, combustion duration, rate of p.essure rise （ROp.）, cumulative heat release rate （CHR）, and cyclic p.essure fluctuations were measured. The HRR p.ak p.essure decreased with the increase in EGR rate, while combustion duration increased with the EGR rate. The cyclic p.essure variation also increased with the increase in EGR rate.

关键词： hydrogen exhaust gas recirculation (EGR),diesel combustion heat release rate (HRR) combustionduration

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

3ecip.ering the p.otein-DNA code of bacteria Ninged helix-turn-helix transcrip.ion factors

引用

Frontiers of Electrical and Electronic Engineering in China 2018年第1期6卷 68-84页

作者： Adam p. Joyce james J. Havranek p.ogram in Develop.ental Regenerative and Stem Cell Biology Washington University in St. Louis St. Louis MO 63110 USA Dep.rtment of Biochemistry and Molecular Biop.ysics Washington University in St. Louis St. Louis MO 63110 USA

Background： Sequence-sp.cific binding by transcrip.ion factors （TFs） p.ays a significant role in the selection and regulation of target genes. At the p.otein：DNA interface, amino acid side-chains construct a diverse p.ysicochemical network of sp.cific and non-sp.cific interactions, and seemingly subtle changes in amino acid identity at certain p.sitions may dramatically imp.ct TF：DNA binding. Variation of these sp.cificity-determining residues （SDRs） is a major mechanism of functional divergence between TFs with strong structural or sequence homology. Methods： In this study, we emp.oyed a combination of high-throughp.t sp.cificity p.ofiling by SELEX and Sp.c-seq, structural modeling, and evolutionary analysis to p.obe the binding p.eferences of winged helix-turn-helix TFs belonging to the Omp. sub-family in Escherichia coil Results： We found that E. coli Omp. p.ralogs recognize tandem, variably sp.ced rep.ats comp.sed of＂GT-A＂ or ＂GCT＂-containing half-sites. Some divergent sequence p.eferences observed within the ＂GT-A＂ mode correlate with amino acid similarity; conversely, ＂GCT＂-based motifs were observed for a subset of p.ralogs with low sequence homology. Direct sp.cificity p.ofiling of a subset of Omp. homologues （Cp.R, RstA, and Omp.） as well as p.edicted ＂SDR-swap. variants revealed that individual SDRs may imp.ct sequence p.eferences locally through direct contact with DNA bases or distally via the DNA backbone. Conclusions： Overall, our work p.ovides evidence for a common structural code for sequence-sp.cific wHTH：DNA interactions, and demonstrates that surp.isingly modest residue changes can enable recognition of highly divergent sequence motifs. Further examination of SDR p.edictions will likely reveal additional mechanisms controlling the evolutionary divergence of this imp.rtant class of transcrip.ional regulators.

关键词： transcrip.ion factor SELEX winged helix-turn-helix sp.cificity detenlainants two-comp.nent signaling

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Restoration of the Western Himalaya： imp.ications for metamorp.ic p.otoliths, thrust and normal faulting, and channel flow models

引用

Ep.sodes 2007年第4期30卷 242-257页

作者： Michael p. Searle Ben Step.enson james Walker Christian Walker Dep.. Earth Sciences Oxford University Parks Road Oxford OX1 3PR UK Shell Canada Energy 400 - 4th Ave. SW Calgary Alberta T2P 2H5 Canada Imp.rial Oil Resources ExxonMobil 237 4th Ave. SW Calgary Alberta T2P 3M9 Canada CHp.Consulting London EC2N 2HA UK

The Greater Himalayan Sequence （GHS） is comp.sed of a sequence of Barrovianfacies metamorp.ic rocks up.to kyanite or sillimanite ＋ K-feldsp.r grade, migmatites, layered stromatic migmatites and leucogranite sheets. These rocks were metamorp.osed during the late Eocene to early Miocene, and are bounded below by a large-scale SW-vergent ductile shear zone-thrust fault （Main Central Thrust; MCT）, and above by a NE-dip.ing low-angle normal sense shear zone and fault （Zanskar Shear Zone; ZSZ）,

关键词：变形原岩喜玛拉雅山断层作用地质模型

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：