检索结果-南通市图书馆

Predictions of the P1 approximation for radiative heat transfer in heterogeneous granular.media

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

Particuology 2023年第11期82卷 25-47页

作者： Jelena macak christoph Goniva Stefan radl DCS Computing GmbH 4020LinzAustria Graz University of Technology Institute of Process and Particle Engineering8010GrazAustria

The P1 approximation is a computationally efficient model for thermal ***,we present a P1 formulation in the context of the combined computational fluid dynamics and discrete element method(CFD-DEm),including closures for dependent scattering and *** available analytical and semi-analytical solutions,we find agreement for steady-state and transient quantities in sizedisperse *** flux is identified as the most sensitive quantity to predict,displaying unphysical spatial *** oscillations are due to a temperature slip at the locations of abrupt change in solid *** propose two techniques that mitigate this effect:smoothing of the radiative properties,and ***,using up to a million times enlarged particles,we demonstrate practically limitless compatibility with ***,we compare predictions made with our code to exper.mental data for a pebble bed under vacuum conditions,and in presence of *** find that a carefully calibrated simulation can replicate trends observed in exper.ments,with relative temperature error of less than 10%.

关键词： CFD-DEm Thermal radiation Coarse-graining P1 Pebble bed nuclear reactor

ANALYSIS OF mULTI-INDEX mONTE CArLO ESTImATOrS FOr A ZAKAI SPDE

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Computational mathematics 2018年第2期36卷 202-236页

作者： christoph reisinger Zhenru Wang mathematical Institute University of Oxford Woodstock Road Oxford OX2 6GG UK

In this article, we propose a space-time multi-Index monte Carlo （mImC） estimator for a one-dimensional parabolic stochastic partial differential equation （SPDE） of Zakai type. We compare the complexity with the multilevel monte Carlo （mLmC） method of Giles and reisinger （2012）, and find, by means of Fourier analysis, that the mImC method：（i） has suboptimal complexity of 0（ε^-21 ｜ogε｜） for a root mean square error （rmSE） z if the same spatial discretisation as in the mLmC method is used; （ii） has a better complexity of 0（ε^-21 ｜ogε｜） if a carefully adapted discretisation is used; （iii） has to be adapted for non-smooth functionals. Numerical tests confirm these findings empirically.

关键词： Parabolic stochastic partial differential equations multilevel monte Carlo,multi-index monte Carlo Stochastic finite differences Zakai equation.

Weather or weathering?Growth of Nothofagus dombeyi on volcanic soils differing in nitrogen and phosphorus concentrations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Plant Ecology 2016年第5期9卷 596-607页

作者： christoph Walter Cecilia A.Pérez Frank m.Thomas Faculty of regional and Environmental Sciences GeobotanyUniversity of TrierBehringstraße 2154296 TrierGermany Departamento de Ecología de Ecosistemas Instituto de Ecología y Biodiversidad(IEB)Alameda 340SantiagoChile

Aims We tested whether—in addition to weather conditions—the concentrations of nitrogen and phosphorus in the substrate have an effect on the radial stem incr.ment of Nothofagus dombeyi trees in old-growth forest stands on volcanic soil at the western slopes of the Andes in South-Central *** We took soil samples and tree incr.ment cores fr.m five proximate sites(1000-1300 m a.s.l.)that are located in the volcanic region of the Conguillío National Park and differ in the age of the substrate(miocene—3500 years B.P.)and in its concentrations of nitrogen(N)and phosphorus(P).The soil samples were also analysed on their concentrations of other plant mineral nutrients,carbon(C)and nitrogen isotope ratios(δ^(15)N).Tree-ring widths and the stem basal area incr.ment(BAI)were related to climate *** selected tree rings,the stable isotope ratios of carbon(δ^(13)C)and oxygen(δ^(18)O)were determined and related to growth and climate *** FindingsConsistent with theory,the soils on the oldest substrate showed the highest(least negative)δ^(15)N values,but mineral N was the only nutrient whose concentration exhibited a straightforward(increasing)relationship with increasing substrate *** BAI was largest on the soil with the highest concentration of plant-available *** contrast to BAI,tree-ring chronologies did not differ among the study ***,tree-ring chronologies and BAI exhibited significantly positive correlations with summer precipitation,and negative correlations,with summer(December)temperature.A negative correlation was found betweenδ^(13)C and precipitation anomalies in the growing season(November.march).We interpret the negative correlations between growth and temperature,and betweenδ^(13)C andδ^(18)O in the tree rings,as an impairment of net carbon assimilation by anomalously warm weather conditions during the growing *** conclude that the growth of *** is mainly affected by high temperature and low precipitation

关键词： Andisol annual ring dendroecology temperate broadleaf forest weather anomalies

Evaluation of Par.metric Limitations in Simulating Greenhouse Gas Fluxes fr.m Irish Arable Soils Using Three Process-Based models

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural Sciences 2016年第8期7卷 503-520页

作者： mohammad I. Khalil mohamed Abdalla Gary Lanigan Bruce Osborne christoph müller UCD School of Biology & Environmental Science and UCD Earth Institute University College Dublin Dublin Ireland Institute of Biological & Environmental Sciences University of Aberdeen Scotland UK Teagasc Environment research Centre Johnstown Castle Wexford Ireland Depar.ment of Plant Ecology Justus-Liebig-University Giessen Giessen Germany

Globally a large number of process-based models have been assessed for quantification of agricultural greenhouse gas (GHG) emissions. modelling approaches minimize the presence of spatial variability of biogeochemical processes, leading to improved estimates of GHGs as well as identifying mitigation and policy options. The comparative performance of the three dynamic models (e.g., DNDC v9.4, DailyDayCent and ECOSSE v5+) with minimum numbers of common input par.meters was evaluated against measured variables. Simulations were performed on conventionally-tilled spring barley crops receiving N fertilizer at 135 - 159 kg·N·ha-1·yr-1 and crop residues at 3 t·ha-1·yr-1. For surface soil nitrate (0 - 10 cm), the ECOSSE and DNDC simulated values showed significant correlations with measured values (r2 = 0.31 - 0.55, p 0.05). Only the ECOSSE-simulated N2O fluxes showed a significant relationship (r2 = 0.33, p 0.05) with values measured fr.m fertilized fields, but not with unfertilized ones. The DNDC and DailyDayCent models significantly underestimated seasonal/annual N2O fluxes compared to ECOSSE, with emission factors (EFs), based on an 8-year average, were 0.09%, 0.31% and 0.52%, respectively. Predictions of ecosystem respiration by both DailyDayCent and DNDC showed reasonable agreement with Eddy Covariance data (r2 = 0.34 - 0.41, p 0.05). Compared to the measured value (3624 kg·C·ha-1·yr-1), the ECOSSE underestimated annual heterotrophic respiration by 7% but this was smaller than the DNDC (50%) and DailyDayCent (24%) estimates. All models simulated CH4 uptake we

关键词： Greenhouse Gases Arable Lands Input Par.meters Process-Based models Ireland

Branched side chains improve molecular packing of non-fullerene acceptors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2021年第9期64卷 1435-1436页

作者： Ning Li christoph J.Brabec Institute of materials for Electronics and Energy Technology(i-mEET) Friedrich-Alexander University Erlangen-NürnbergMartensstraße 7Erlangen91058Germany Helmholtz-Institute Erlangen-Nürnberg(HI ErN) Immerwahrstraße 2Erlangen91058Germany

As one of the pr.mising emerging photovoltaic technologies(PVs),organic solar cells(OSCs)have received extensive attention fr.m both scientific and industry *** advantages of OSCs,such as low toxicity,high power-toweight ratio,and easy manufacturing and upscaling,guarantee their contribution to versatile applications powered by clean and renewable solar energy,for instance.

关键词： chains packing versatile

Deciphering the Origins of P1-Induced Power Losses in Cu(In_(x),Ga_(1–x))Se2(CIGS)modules Through Hyperspectral Luminescence

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

Engineering 2020年第12期6卷 1395-1402页

作者： César Omar r.mírez Quiroz Laura-Isabelle Dion-Bertrand christoph J.Brabec Joachim müller Kay Orgassa NICE Solar Energy GmbH Schwaebisch Hall 74523Germany Photon Etc.Inc. MontréalQC H2S 2X3Canada Institute of materials for Electronics and Energy Technology(i-mEET) Department for Material ScienceFriedrich-Alexander-Universität Erlangen-Nürnberg(FAU)Erlangen 91058Germany Helmholtz Institute Erlangen-Nürnberg for renewable Energy Production Energy(IEK-11)Forschungszentrum Jülich GmbHErlangen 91058Germany

In this report,we show that hyperspectral high-resolution photoluminescence mapping is a powerful tool for the selection and optimiz1ation of the laser ablation processes used for the patterning interconnections of subcells on Cu(Inx,Ga1-x)Se2(CIGS)*** this way,we show that in-depth monitoring of material degradation in the vicinity of the ablation region and the identification of the underlying mechanisms can be ***,by analyzing the standard P1 patterning line ablated before the CIGS deposition,we reveal an anomalous emission-quenching effect that follows the edge of the molybdenum groove *** further rationalize the origins of this effect by comparing the topography of the P1 edge through a scanning electron microscope(SEm)cross-section,where a reduction of the photoemission cannot be explained by a thickness *** also investigate the laser-induced damage on P1 patterning lines performed after the deposition of *** then document,for the first time,the existence of a short-range damaged area,which is independent of the application of an optical aperture on the laser *** findings pave the way for a better understanding of P1-induced power losses and introduce new insights into the improvement of current strategies for industry-relevant module interconnection schemes.

关键词： Cu(In_(x),Ga_(1-x))Se2 Cell-to-module efficiency gap P1-induced power losses Hyperspectral photoluminescence Laser ablation short-range heat effect

Epigenetic changes of DNA repair genes in cancer

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

分子细胞生物学报:英文版 2011年第1期3卷 51-58页

作者： christoph Lahtz Gerd P.Pfeifer Depar.ment of Cancer Biology Beckman Research InstituteCity of HopeDuarteCA 91010USA

‘Every Hour Hurts,The Last One Kills’.That is an old saying about getting *** day,thousands of DNA damaging events take place in each cell of our body,but efficient DNA repair systems have evolved to prevent ***,our DNA repair system and that of most other organisms are not as perfect as that of Deinococcus radiodurans,for example,which is able to repair.massive amounts of DNA damage at one *** many instances,accumulation of DNA damage has been linked to cancer,and genetic deficiencies in specific DNA repair genes are associated with tumor-prone *** addition to mutations,which can be either inherited or somatically acquired,epigenetic silencing of DNA repair genes may pr.mote *** review will summarize current knowledge of the epigenetic inactivation of different DNA repair components in human cancer.

关键词： DNA methylation DNA repair epigenetics

Aberrant DNA methylation reprogr.mming during induced pluripotent stem cell generation is dependent on the choice of reprogr.mming factors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cell regeneration 2014年第1期3卷 30-43页

作者： Aline C Planello Junfeng Ji Vivek Sharma rajat Singhania Faridah mbabaali Fabian müller Javier A Alfaro christoph Bock Daniel D De Carvalho Nizar N Batada Campbell Family Cancer research Institute Ontario Cancer InstitutePrincess Margaret Cancer CentreUniversity Health NetworkTorontoON M5G 2 M9Canada Depar.ment of morphology Piracicaba Dental SchoolUniversity of CampinasPiracicabaSPBrazil Ontario Institute for Cancer research TorontoOntario M4G 0A3Canada Center of Stem Cell and Developmental Biology Zhejiang UniversityHangzhouZhejiang Province 310058China National Cancer Institute NIHBethesdaMD 20892USA Depar.ment of medical Biophysics University of TorontoTorontoON M5G 2 M9Canada max Planck Institute for Informatics Campus E1.466123 SaarbrückenGermany Cemm research Center for.molecular.medicine of the Austrian Academy of Sciences Lazarettgasse 141090 ViennaAustria Depar.ment of Laboratory medicine Medical University of ViennaWähringer Gürtel 18-201090 ViennaAustria

The conversion of somatic cells into pluripotent stem cells via overexpression of reprogr.mming factors involvesepigenetic r.modeling. DNA methylation at a significant proportion of CpG sites in induced pluripotent stem cells(iPSCs) differs fr.m that of embryonic stem cells (ESCs). Whether different sets of reprogr.mming factors influencethe type and extent of aberrant DNA methylation in iPSCs differently r.mains unknown. In order to help resolvethis critical question, we generated human iPSCs fr.m a common fibroblast cell source using either the Yamanakafactors (OCT4, SOX2, KLF4 and cmYC) or the Thomson factors (OCT4, SOX2, NANOG and LIN28), and determinedtheir genome-wide DNA methylation profiles. In addition to shared DNA methylation aberrations present in all ouriPSCs, we identified Yamanaka-iPSC (Y-iPSC)-specific and Thomson-iPSC (T-iPSC)-specific recurrent ***, not only were the genomic locations of the aberrations different but also their types: reprogr.mmingwith Yamanaka factors mainly resulted in failure to demethylate CpGs, whereas reprogr.mming with Thomsonfactors mainly resulted in failure to methylate CpGs. Differences in the level of transcripts encoding DNmT3b andTET3 between Y-iPSCs and T-iPSCs may contribute partially to the distinct types of aberrations. Finally, de novoaberrantly methylated genes in Y-iPSCs were enriched for NANOG targets that are also aberrantly methylated insome cancers. Our study thus reveals that the choice of reprogr.mming factors influences the amount, location,and class of DNA methylation aberrations in iPSCs. These findings may provide clues into how to produce humaniPSCs with fewer DNA methylation abnormalities.

关键词： SOX2 progr.mming Thomson

Trunk Flexion to Extension Strength ratio of 11- to 18- Year Old Youth Ski racers: Data fr.m 15 Years of Talent Development in Austria

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Science in Sport and Exercise 2021年第3期3卷 I0001-I0009页

作者： Lisa Steidl-muller Carson Patterson roland Luchner christoph Ebenbichler Carolin Hildebrandt Christian raschner Depar.ment of Sport Science University of InnsbruckInnsbruckAustria

Purpose The aim of the present study was to evaluate the trunk strength capacity of alpine ski racers aged 10-18 years,who were tested during the last 15 years,to identify reference values for trunk flexor to extensor strength ratios according to age and *** In total,2841 participants(1605 males,1236 females;10-18 years)were included,who were pupils of a famous skiing-specific secondary modern school or.members of the provincial ski team between 2006 and *** maximum isometric trunk flexion and extension strength was measured using the slightly modified Back ***-specific differ-ences were assessed with Student’s t test or.mann-Whitney-U *** analyses of variance or Kruskal-Wallis-H tests were used to assess differences between age *** sex-and age-specific reference values were calculated(norm area:mean±½standard deviation).results Sex-specific differences were found for both flexion(starting at 11 years)and extension strength(starting at 12 years)(Pr flexion to extension strength ratios were identified for.males(0.89±0.18)compared with females(0.82±0.15),but the ratios r.mained constant across age groups for both *** The present study provides age-and sex-specific reference values for trunk flexion to extension strength ratios for 10-to 18-year old youth and adolescent ski *** data of the present study represent a large data pool of youth ski racers at a high-performance level;thus,coaches can use the reference values for comparing the ratios of their athletes.

关键词： Core strength Youth athletes Alpine ski racing Talent development