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Decarbonising energy: The developing international activity in hydrogen technologies and fuel cells

journal of Energy Chemistry 2020年第12期29卷 405-415页

作者： john Meurig thomas Peter P.Edwards Peter j.Dobson Gari P.Owend Department of Materials Science&Metallurgy University of CambridgeCambridge CB30FSUK King Abdulaziz City for Science and Technology(KACST)-Oxford Centre of Excellence in Petrochemicals and Inorganic Chemistry Laboratory University of OxfordOxford OX13QRUK The Queen’s College University of OxfordOxford OX14AWUK Annwvyn Solutions(Independent Consultant) BromleyKent BR13DWUK

Hydrogen technologies and fuel cells offer an alternative and improved solution for a decarbonised energy *** cells are electrochemical converters;transforming hydrogen (or energy sources containing hydrogen) and oxygen directly into *** hydrogen fuel cell,invented in 1839,permits the generation of electrical energy with high efficiency through a non-combustion,electrochemical process and,importantly,without the emission ofits point of ***,despite numerous efforts to exploit the obvious attractions of hydrogen technologies and hydrogen fuel cells,various challenges have been encountered,some of which are reviewed ***,however,given the exigent need to urgently seek low-carbon paths for humankind’s energy future,numerous countries are advancing the deployment of hydrogen technologies and hydrogen fuel cells not only for transport,but also as a means of the storage of excess renewable energy from,for example,wind and solar ***,hydrogen is also being blended into the natural gas supplies used in domestic heating and targeted in the decarbonisation of critical,large-scale industrial processes such as steel *** briefly review specific examples in countries such as japan,South Korea and the People’s Republic of China,as well as selected examples from Europe and North America in the utilization of hydrogen technologies and hydrogen fuel cells.

关键词： Decarbonisation Hydrogen Energy Hydrogen Economy Fuel cells Environment Sustainability

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Determination of quantitative structure-property and structure-process relationships for graphene production in water

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Nano Research 2015年第6期8卷 1865-1881页

作者： thomas j. Nacken Cornelia Damm Haichen Xing Andreas ROger Wolfgang Peukert Institute of Particle Technology (LFG) Friedrich-Alexander University Erlangen-NOrnberg (FAU) Cauerstrasse 4 91058 Erlangen Germany

A scalable method for graphene and few-layer graphene （FLG） production by graphite delamination in aqueous solutions of the nonionic surfactant TWEEN 80 （TW80） using stirred-media mills is presented. Delaminated product analysis using statistical Raman spectroscopy yielded extensive processing-structure-property relationships that revealed how stress intensity and specific energy input, i.e., the process parameters, govern the yield of graphene production and defect formation. The dispersed carbon concentration increased but the content and the quality of the FLG product decreased sharply with higher specific energy input. The FLG content of the product was up to 90%, especially for low specific energy input. Moreover, Raman analyses revealed that stress intensities greater than about I nj were related to significant defect formation in the product particles. Another key parameter for graphene production is solvent viscosity. The FLG concentration in the product increased by a factor of 10 when the solvent＇s viscosity was increased from 1 to 6 mPa-s because shear- and friction-induced delamination was enhanced and in-plane fracture was reduced due to dampening of bead motion. Based on the processing-structure-property relationships found, we propose that the delamination process can be designed in such way that the product consists, almost totally, of FLG and that single-layer graphene is produced. The scalability of graphene production by stirred-media delamination was demonstrated when an increase in the batch size from 0.2 to 2 L had no significant effect on product quality.

关键词： graphite delamination few-layer graphene graphene stirred-media millprocess parameters statistical Ramanspectroscopy

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Modeling the oxidative consumption of curcumin from controlled released poly(betaamino ester)microparticles in the presence of a free radical generating system

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Regenerative Biomaterials 2019年第4期6卷 201-210页

作者： Carolyn T.jordan j.Zach Hilt thomas D.Dziubla Department of Chemical and Materials Engineering University of KentuckyLexingtonKY 40506USA

Despite the promise of its therapeutic benefits,curcumin as a free molecule has failed to demonstrate significant clinical ***,its inherently poor stability and rapid clearance is a significant reason for these negative *** incorporation of curcumin into the backbone of a crosslinked hydrogel that utilizes poly(beta-amino ester)(PBAE)chemistry can provide a tunable protective network with the ability to release at a controlled rate while improving its therapeutic *** of curcumin conjugated PBAE microparticles controlled release delivery system in the presence of oxidative environments was studied for the first time,where consumption rates of active curcumin and release products were *** constituent amount of curcumin present in solution was improved by incorporating the active into the network in comparison to curcumin as a free *** curcumin conjugated PBAE microparticles will provide a design platform to improve translation and overall success in delivering a therapeutic agent that matches levels of oxidative stress.

关键词： oxidative stress wound healing oral mucositis drug delivery

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The Chapman-Richards Distribution and its Relationship to the Generalized Beta

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Forest Ecosystems 2019年第3期6卷 219-235页

作者： jeffrey H.Gove thomas B.Lynch Mark j.Ducey USDA Forest Service Northern Research Station271 Mast Road Durham 03824NHUSA Professor Emeritus Department of Natural Resource Ecology and ManagementOklahoma State UniversityAg Hall Room 008CStillwater 74078OKUSA Department of Natural Resources and the Environment University of New Hampshire114 James Hall Durham 03824NHUSA

Background: The Chapman-Richards distribution is developed as a special case of the equilibrium solution to the McKendrick-Von Foerster equation. The Chapman-Richards distribution incorporates the vital rate assumptions of the Chapman-Richards growth function, constant mortality and recruitment into the mathematical form of the distribution. Therefore, unlike 'assumed' distribution models, it is intrinsically linked with the underlying vital rates for the forest area under consideration. Methods: It is shown that the Chapman-Richards distribution can be recast as a subset of the generalized beta distribution of the first kind, a rich family of assumed probability distribution models with known properties. These known properties for the generalized beta are then immediately available for the Chapman-Richards distribution, such as the form of the compatible basal area-size distribution. A simple two-stage procedure is proposed for the estimation of the model parameters and simulation experiments are conducted to validate the procedure for four different possible distribution shapes. Results: The simulations explore the efficacy of the two-stage estimation procedure;these cover the estimation of the growth equation and mortality-recruitment derives from the equilibrium assumption. The parameter estimates are shown to depend on both the sample size and the amount of noise imparted to the synthetic measurements. The results vary somewhat by distribution shape, with the smaller, noisier samples providing less reliable estimates of the vital rates and final distribution forms. Conclusions: The Chapman-Richards distribution in its original form, or recast as a generalized beta form, presents a potentially useful model integrating vital rates and stand diameters into a flexible family of resultant distributions shapes. The data requirements are modest, and parameter estimation is straightforward provided the minimal recommended sample sizes are obtained.

关键词： Diameter distributions Chapman-Richards growth Generalized beta distribution of the first kind Maximum likelihood McKendrick-Von Foerster equation Physiologically structured population model Size-structured distributions

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Felsenstein＇s ＂one-allele model＂ of speciation： The role of philopatry in the initial stages of host plant mediated reproductive isolation in Enchenopa binotata

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Current Zoology 2013年第5期59卷 658-666页

作者： Frank W. STEARNS Kelley j. TILMON thomas K. WOOD Department of Biology Biology-Psychology Building University of Maryland College Park MD 20742 USA Department of Plant Science Plant Science Building South Dakota State University Brookings SD 57007 USA Department of Entomology and Applied Ecology 250 Townsend Hall University of Delaware Newark DE 19716 USA

The study of speciation genetics is primarily concerned with identifying the genetic traits that allow divergent selec- tion to overcome the homogenizing effects of gene flow. Felsenstein reviewed this race between gene flow and selection, con- cluding that speciation with gene flow was unlikely under a ＂two-allele model＂（where two traits were necessary for reproductive isolation） but that divergence could occur quite easily under a ＂one-allele model.＂ Despite this finding, much of the sympatric speciation research involving phytophagous insects has relied on a two-trait model, where insects evolve both preferences for and increased performance on novel host plants. Philopatry （a tendency to remain where one was born） is known to occur in phyto- phagous insects and is a single trait isolation mechanism. However, it is traditionally invoked as simply augmenting reproductive isolation. Species in the Enchenopa binotata complex are believed to have speciated in sympatry. They exhibit host plant prefe- rences, host specific performance advantages and strong philopatry. We experimentally shifted E. binotata to evolutionarily novel host plants. Previous research has demonstrated that the experimental population of insects possesses genetic variation in prefe- rence and performance to the novel host. The degree of philopatry at mating and egg-laying was assayed for the first four years under full choice conditions. Host plant preference and performance was assayed after eight years. Philopatry was an immediate and strong isolating mechanism, while preference for and performance on the novel host lagged. We therefore suggest that philo- patry may be a more important mechanism in the early stages of a host shift than previously believed [Current Zoology 59 （5）： 658-666, 2013].

关键词： Philopatry Enchenopa Ecological Speciation Sympatric Speciation

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Promoting electrochemical reduction of CO_(2) to ethanol by B/N-doped sp^(3)/sp^(2) nanocarbon electrode

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Chinese Chemical Letters 2022年第10期33卷 4691-4694页

作者： Yanming Liu Haolei Yang Xinfei Fan Bing Shan thomas j.Meyer Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China Department of Chemistry University of North Carolina at Chapel HillChapel HillNorth Carolina 27599United States College of Environmental Science and Engineering Dalian Maritime UniversityDalian 116026China

Electrochemical reduction of CO_(2) to value-added chemicals holds promise for carbon utilization and renewable electricity ***,selective CO_(2) reduction to multi-carbon fuels remains a significant ***,we report that B/N-doped sp^(3)/sp^(2) hybridized nanocarbon(BNHC),consisting of ultra-small nanoparticles with a sp^(3) carbon core covered by a sp^(2) carbon shell,is an efficient electrocatalyst for electrochemical reduction of CO_(2) to ethanol at relatively low ***_(2) reduction occurs with a Faradaic efficiency of 58.8%-69.1% for ethanol and acetate production at -0.5∼-0.6 V(***),among which 51.6%-56.0% is for *** high selectivity for ethanol is due to the integrated effect of sp^(3)/sp^(2) carbon and B/N *** sp^(3) carbon and B/N doping contribute to enhanced ethanol production with sp^(2) carbon reducing the overpotential for CO_(2) reduction to ethanol.

关键词： CO_(2)reduction Ethanol B/N-doped sp^(3)/sp^(2)hybridized nanocarbon Electrocatalysis multi-carbon product

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Granular titanite from the Roter Kamm crater in Namibia:Product of regional metamorphism,not meteorite impact

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Geoscience Frontiers 2022年第3期13卷 156-163页

作者： Aaron j.Cavosie Christopher j.Spencer Noreen Evans Kai Rankenburg Robert j.thomas Paul H.Macey Space Science and Technology Centre and The Institute for Geoscience Research School of Earth and Planetary ScienceCurtin UniversityPerthWA 6102Australia Dept.of Geological Sciences and Geological Engineering Queen’s UniversityOntarioCanada john de Laeter Centre Curtin UniversityPerthWA 6102Australia Council for Geoscience BellvilleWestern CapeSouth Africa

Accessory minerals with so-called granular texture have risen in importance as geochronological tools for U-Pb dating of meteorite impact events. Grain-scale recrystallization, typically triggered by a combination of high-strain deformation and post-impact heating, can create a polycrystalline microstructure consisting of neoblasts that expel radiogenic Pb, which are thus ideal for isotopic dating. While granular domains in zircon and monazite from shocked rocks have been demonstrated to preserve impact ages,few U-Pb dating studies have been conducted on granular microstructures in titanite(CaTiSiO;). Here we report the occurrence of granular-textured titanite from ~2020 Ma granite basement rock exposed in the rim of the 4–5 Ma Roter Kamm impact structure in Namibia. Orientation mapping reveals two microstructurally distinct titanite populations: one consisting of strained/deformed grains, and the other consisting of grains that comprise aggregates of strain-free neoblasts. In situ U-Pb geochronology on 37 grains shows that most grains from both titanite populations yield indistinguishable U-Pb dates of ca.1025 Ma, consistent with the observed microstructures forming during the Mesoproterozoic Namaqua Orogeny. Only four grains preserved older age domains, recording ca. 1875 Ma Paleoproterozoic metamorphism. Two significant observations emerge:(1) none of the analyzed titanite grains yield the 2020 Ma igneous crystallization age previously established from zircon in the same sample, and(2) no age-resetting was detected that could be attributed to the 4 to 5 Ma Roter Kamm impact *** the similarity of the neoblastic microstructure to minerals from other sites with an established impact provenance, the granular texture and near-complete Pb-loss in titanite from Roter Kamm granite instead records a Paleo-to Mesoproterozoic polymetamorphic history, rather than Miocene age shockrelated processes. These results highlight the critical importance of grain-scale cont

关键词： Namibia Roter Kamm Titanite EBSD Geochronology

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Critical analysis of feeding jejunostomy following resection of upper gastrointestinal malignancies

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World journal of Gastrointestinal Surgery 2017年第2期9卷 53-60页

作者： Andrew M Blakely Saad Ajmal Rachel E Sargent thomas T Ng thomas j Miner Department of Surgery Rhode Island HospitalProvidence Warren Alpert Medical School of Brown University Providence

AIM To assess nutritional recovery,particularly regarding feeding jejunostomy tube(FjT)utilization,following upper gastrointestinal resection for malignancy. METHODS A retrospective review was performed of a prospectively-maintained database of adult patients who underwent esophagectomy or gastrectomy(subtotal or total)for cancer with curative intent,from january 2001 to june 2014. Patient demographics,the approach to esophagectomy,the extent of gastrectomy,FjT placement and utilization at discharge,administration of parenteral nutrition(PN),and complications were evaluated. All patients were followed for at least ninety days or until *** The 287 patients underwent upper GI resection,comprised of 182 esophagectomy(n=107 transhiatal,58.7%; n=56 Ivor-Lewis,30.7%)and 105 gastrectomy [n=63 subtotal(SG),60.0%; n=42 total(TG),40.0%]. 181 of 182 esophagectomy patients underwent FjT,compared with 47 of 105 gastrectomy patients(99.5% vs 44.8%,P jT placement more often following gastrectomy than esophagectomy(n=11,23.4% vs n=7,3.9%,P=0.0001). FjT-specific complications requiring reoperation within 30 d of resection occurred more commonly in the gastrectomy group(n=6),all after TG,compared to 1 esophagectomy patient(12.8% vs 0.6%,P=0.0003). Six of 7 patients(85.7%)who experienced tube-re

关键词： Feeding jejunostomy Esophagectomy Gastrectomy Nutritional recovery Outcomes

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Field Observations of the Vulnerable Impressed Tortoise, Manouria impressa, from Southern Laos and Notes on Local Chelonian Trade

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Asian Herpetological Research 2013年第2期4卷 151-154页

作者： thomas CALAME thomas N. E. GRAY Martha HURLEY Robert j. TIMMINS Khamhou THONGSAMOUTH WWF Greater Mekong House No. 39Unit 05Ban SaylomVientianeLao PDR Société d'Histoire Naturelle Alcide-d'Orbigny 57rue de Gergovie63170 AubièreFrance Global Wildlife Conservation

Observations of wild chelonians in Indochina are uncommon with most records and specimens coming from the commercial wildlife trade. During the surveys of the Xe Sap National Protected Area in southern Laos between February and May 2012, four impressed tortoises, Manouria impressa(IUCN Red List: Vulnerable) were found in three separate field locations. There are few published observations of this species in the wild. We also present data on threats and local value of chelonians in the wildlife trade.

关键词： Xe Sap National Protected Area Laos Manouria impressa wildlife trade

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Energy and blast performance of beryllium in a model thermobaric composition in comparison with aluminum and magnesium

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Defence technology 2024年第6期 13页

作者： thomas M.Klap?tke Stanis?aw Cudzi?o Waldemar A.Trzciński józef Paszula

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