检索结果-南通市图书馆

Binding energies and interaction origins between nonclassical single-electron hydrogen,sodium and lithium bonds and neutral boron-containing radicals:a theoretical investigation

引用

Chinese Science Bulletin 2014年第21期59卷 2597-2607页

作者： Zhifeng Li Xiaoping Yang nathan j.deyonker Xianyan Xu Zhen Guo Cunyuan Zhao Key Laboratory for New Molecule Design and Function of Gansu Universities College of Life Science and ChemistryTianshui Normal University Department of Chemistry The University of MemphisMemphisTN 38152-3550USA School of Chemistry and Chemical Engineering Sun Yat-Sen University Department of Chemistry State Key Laboratory of Synthetic ChemistryThe University of Hong Kong

Nonclassical single electron hydrogen,sodium and lithium bonds(SEHBs,SENaBs and SELiBs)between single electron acceptors X–A(A=H,Na,Li;X=CN,HCC,HO,NC,CF3)and neutral radicals BY2(Y=H,OH,CH3)and have been systematically investigated by high level theoretical methods,such as second-order Mφller-Plesset perturbation theory(MP2),spin-component-scaled MφllerPlesset theory(SCS-MP2),the coupled cluster method with perturbative triples(CCSD(T)),and the correlation consistent composite approach(ccCA).Binding energies have been corrected for zero-point vibrational effects and(when applicable)basis set superposition *** quantum theory of atoms in molecules(AIM)and natural bond orbital(NBO)analyses were also employed to qualitatively characterize the single electron bond *** stabilization energy was partitioned via the localized molecular orbital energy decomposition analysis(LMOEDA)method,and both electrostatic and exchange interactions were seen to be major driving forces for the complex ***,the sum of the energy contributors of exchange(EEX),repulsion(EREP),polarization(EPOL),dispersion(EDIS)is close to zero and the changes in the interaction energy follow the trend of the electrostatic energy(EES).We observe several linear relationships among the optimized intermolecular parameters and the interaction energies of the various complexes.

关键词：相互作用能单电子非经典结合能中性债券能量分解分析 CCSD(T)

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

Validating neural networks for spectroscopic classification on a universal synthetic dataset

引用

npj Computational Materials 2023年第1期9卷 1325-1336页

作者： jan Schuetzke nathan j.Szymanski Markus Reischl Institute for Automation and Applied Informatics Karlsruhe Institute of TechnologyKarlsruhe 76131Germany Department of Materials Science&Engineering Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA Department of Materials Science&Engineering UC BerkeleyBerkeleyCA 94720USA

To aid the development of machine learning models for automated spectroscopic data classification,we created a universal synthetic dataset for the validation of their *** dataset mimics the characteristic appearance of experimental measurements from techniques such as X-ray diffraction,nuclear magnetic resonance,and Raman spectroscopy among *** applied eight neural network architectures to classify artificial spectra,evaluating their ability to handle common experimental *** all models achieved over 98%accuracy on the synthetic dataset,misclassifications occurred when spectra had overlapping peaks or *** found that non-linear activation functions,specifically ReLU in the fully-connected layers,were crucial for distinguishing between these classes,while adding more sophisticated components,such as residual blocks or normalization layers,provided no performance *** on these findings,we summarize key design principles for neural networks in spectroscopic data classification and publicly share all scripts used in this study.

关键词： spectroscopic adding classify

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

Functional perspectives on tropical tree demography and forest dynamics

引用

Ecological Processes 2019年第1期8卷 1-11页

作者： Samantha j.Worthy nathan G.Swenson Department of Biology University of MarylandCollege ParkMD 20742USA

Disentangling the processes that drive population,community and whole forest structure and dynamics is a *** becomes a grand challenge in the tropics where there are a large number of species,small population sizes,less research infrastructure,and a relatively smaller number of researchers compared to the temperate *** this grand challenge,we argue,requires detailed knowledge of the functioning of individuals and *** this end,researchers frequently employ plant functional traits to study tree populations and ***,we review this approach by first providing a basic background regarding the major trait axes generally of *** then discuss how these axes may be or have been applied from ecosystem to community and population *** doing so,we highlight where the functional trait research program has failed in tropical tree ecology and where it can be improved or ***,we provide a perspective regarding how functional trait and emerging‘omics approaches can be integrated to address large questions facing the *** intention throughout is to provide an entryway into this literature for an early career researcher rather than a comprehensive review of all possible studies that have taken place in tropical forests.

关键词： Demographic rate Functional diversity Functional trait Transcriptome Tropical forest Tropical rain forest

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

Adaptively driven X-ray diffraction guided by machine learning for autonomous phase identification

引用

npj Computational Materials 2023年第1期9卷 2036-2043页

作者： nathan j.Szymanski Christopher j.Bartel Yan Zeng Mouhamad Diallo Haegyeom Kim Gerbrand Ceder Department of Materials Science&Engineering UC BerkeleyBerkeleyCA 94720USA Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Machine learning(ML)has become a valuable tool to assist and improve materials characterization,enabling automated interpretation of experimental results with techniques such as X-ray diffraction(XRD)and electron *** ML models are fast once trained,there is a key opportunity to bring interpretation in-line with experiments and make on-the-fly decisions to achieve optimal measurement effectiveness,which creates broad opportunities for rapid learning and information extraction from ***,we demonstrate such a capability with the development of autonomous and adaptive *** coupling an ML algorithm with a physical diffractometer,this method integrates diffraction and analysis such that early experimental information is leveraged to steer measurements toward features that improve the confidence of a model trained to identify crystalline *** validate the effectiveness of an adaptive approach by showing that ML-driven XRD can accurately detect trace amounts of materials in multi-phase mixtures with short measurement *** improved speed of phase detection also enables in situ identification of short-lived intermediate phases formed during solid-state reactions using a standard in-house *** findings showcase the advantages of in-line ML for materials characterization and point to the possibility of more general approaches for adaptive experimentation.

关键词： phase diffraction autonomous

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

Iron and non-alcoholic fatty liver disease

引用

World journal of Gastroenterology 2016年第36期22卷 8112-8122页

作者： Laurence j Britton V nathan Subramaniam Darrell HG Crawford Gallipoli Medical Research Institute The University of Queensland Greenslopes Private Hospital Brisbance Queensland 4120 Australia The Princess Alexandra Hospital Queensland 4120 Australia QIMR Berghofer Medical Research Institute Queensland 4120 Australia

The mechanisms that promote liver injury in non-alcoholic fatty liver disease(NAFLD) are yet to be thoroughly elucidated. As such, effective treatment strategies are lacking and novel therapeutic targets are required. Iron has been widely implicated in the pathogenesis of NAFLD and represents a potential target for treatment. Relationships between serum ferritin concentration and NAFLD are noted in a majority of studies, although serum ferritin is an imprecise measure of iron loading. Numerous mechanisms for a pathogenic role of hepatic iron in NAFLD have been demonstrated in animal and cell culture models. However, the human data linking hepatic iron to liver injury in NAFLD is less clear, with seemingly conflicting evidence, supporting either an effect of iron in hepatocytes or within reticulo-endothelial cells. Adipose tissue has emerged as a key site at which iron may have a pathogenic role in NAFLD. Evidence for this comes indirectly from studies that have evaluated the role of adipose tissue iron with respect to insulin resistance. Adding further complexity, multiple strands of evidence support an effect of NAFLD itself on iron metabolism. In this review, we summarise the human and basic science data that has evaluated the role of iron in NAFLD pathogenesis.

关键词： Iron Fatty liver Liver steatosis Insulin resistance Steatohepatitis Diabetes mellitus Adipose tissue

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

Use of donepezil for neurocognitive recovery after brain injury in adult and pediatric populations:a scoping review

引用

Neural Regeneration Research 2024年第8期19卷 1686-1695页

作者： Avery L.Miller nathan K.Evanson j.Michael Taylor University of Cincinnati College of Medicine CincinnatiOHUSA Department of Pediatrics University of CincinnatiCincinnatiOHUSA Department of Neurology and Rehabilitation Medicine University of CincinnatiCincinnatiOHUSA Division of Pediatric Rehabilitation Medicine Cincinnati Children’s Hospital Medical CenterCincinnatiOHUSA Division of Neurology Cincinnati Children’s Hospital Medical CenterCincinnatiOHUSA

There are few pharmacologic options for the treatment of cognitive deficits associated with traumatic brain injury in pediatric *** inhibitors such as donepezil have been evaluated in adult patients after traumatic brain injury,but relatively less is known about the effect in pediatric *** goal of this review is to identify knowledge gaps in the efficacy and safety of acetylcholinesterase inhibito rs as a potential a djuvant treatment fo r neurocognitive decline in pediatric patients with traumatic brain *** queried PubMed to identify literature published from database inception thro ugh june 2023 desc ribing the use of donepezil in young adult traumatic brain injury and pediatric patients with predefined *** on preselected search criteria,340 unique papers we re selected for title and abstra ct ***-two reco rds were reviewed in full after eliminating preclinical studies and pape rs outside the scope of the *** adult traumatic brain injury,we review results from 14 papers detailing 227 subjects where evidence suggests donepezil is well tole rated and shows both objective and patient-reported efficacy for reducing cognitive *** children,3 pape rs report on 5 children recovering from traumatic brain injury,showing limited *** additional 15 pediatric studies conducted in populations at risk for cognitive dysfunction provide a broader look at safety and efficacy in 210 patients in the pediatric age *** its promise for efficacy in adults with traumatic brain injury and tole rability in pediatric patients,we believe further study of donepezil for children and adolescents with traumatic brain injury is warranted.

关键词： acetylcholinesterase inhibitor adult cognition donepezil pediatrics traumatic brain injury

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

Differential effects of two dominant plant species on community structure and invasibility in an old-field ecosystem

引用

journal of Plant Ecology 2011年第3期4卷 123-131页

作者： Lara Souza jake F.Weltzin nathan j.Sanders Department of Ecology and Evolutionary Biology University of Tennessee1416 Circle DriveKnoxvilleTN 37996USA USA National Phenology Network National Coordinating Office1955 East 6th StreetTucsonAZ 85719USA

Aims In this study,we examined the effects of Solidago altissima(hereafter Solidago)and two species in the genus Verbesina,Verbesina virginica and Verbesina occidentalis(hereafter Verbesina),on the structure of an old-field plant community and establishment by an invasive plant species,Lespedeza cuneata(hereafter Lespedeza).Methods We removed Solidago,Verbesina and both Solidago and Verbesina from 4m^(-2)plots in an intact old-field community during two growing *** then quantified the effects of these removals on richness,evenness,diversity and composition of the subdominant plant *** also measured the total aboveground biomass and the aboveground biomass of the subdominant *** assess how these removals affected establishment by Lespedeza,we planted 20 seeds in each plot and tracked seedling emergence and survival for one growing *** Findings Subdominant community evenness and Shannon diversity were higher in plots from which Solidago and Verbesina were removed relative to control ***,there were no effects of dominant species removal on species richness or composition of the subdominant *** aboveground biomass was not affected by dominant species removal,suggesting that the community of subdominant species exhibited *** fact,subdominant community biomass was greater when Solidago,but not Verbesina,was *** availability was also greater in plots where Solidago was removed relative to control plots throughout the growing *** addition,removal of dominant species,in particular Solidago,indirectly reduced the emergence,but not survival,of Lespedeza seedlings by directly promoting subdominant community *** together,our results suggest that dominant old-field plant species affect subdominant community structure and indirectly promote establishment by Lespedeza.

关键词： compensation establishment invasive Lespedeza cuneata Solidago Verbesina

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

PIV measurements of turbulent jets issuing from triangular and circular orifice plates

引用

Science China(Physics,Mechanics & Astronomy) 2013年第6期56卷 1176-1186页

作者： XU MinYi ZHANG jianPeng MI jianChun nathan G j KALT P A M Marine Engineering College Dalian Maritime University State Key Laboratory of Turbulence & Complex Systems College of EngineeringPeking University Centre for Energy Technology and School of Mechanical Engineering University of AdelaideSA 5005Australia

The present study experimentally investigated the near-field flow mixing characteristics of two turbulent jets issuing from equilateral triangular and circular orifice plates into effectively unbounded surroundings,*** particle image velocimetry(PIV) was applied to measure the velocity field at the same Reynolds number of Re=50,000,where Re = UeDe /with Ue being the exit bulk velocity and the kinematic viscosity of fluid,D e the equivalent *** instantaneous velocity,mean velocity,Reynolds stresses were *** the mean velocity field,the centreline velocity decay rate and half-velocity width were *** the mixing characteristics of the two jets,it is found that the triangular jet has a faster mixing rate than the circular *** triangular jet entrainments with the ambient fluid at a higher rate in the near *** is evidenced by a shorter unmixed core,faster Reynolds stress and centreline turbulence intensity *** primary coherent structures in the near field are found to break down more rapidly in the triangular jet as compared to the circular *** the entire measurement region,the triangular jet maintained a higher rate of decay and ***,all components of Reynolds stress of the triangular jet appear to reach their peaks earlier,and then decay more rapidly than those of the circular *** addition,the axis-switching phenomenon is observed in the triangular jet.

关键词： triangular jet turbulent mixing coherent structures axis-switching

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

Metamaterial-based graphene thermal emitter

引用

Nano Research 2018年第7期11卷 3567-3573页

作者： Cheng Shi nathan H. Mahlmeister Isaac j. Luxmoore Geoffrey R. Nash College of Engineering Mathematics and PhysicaI Sciences University of Exeter Exeter EX4 4QF UK

A thermal emitter composed of a frequency-selective surface metamaterial layer and a hexagonal boron nitride-encapsulated graphene filament is demonstrated. The broadband thermal emission of the metamaterial （consisting of ring resonators） was tailored into two discrete bands, and the measured reflection and emission spectra agreed well with the simulation results. The high modulation frequencies that can be obtained in these devices, coupled with their operation in air, confirm their feasibility for use in applications such as gas sensing.

关键词： graphene hexagonal boron nitride thermal emitter infrared metamaterial

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

Photocatalytic OH radical formation and quantification over TiO_2 P25:Producing a robust and optimised screening method

引用

Chinese Chemical Letters 2018年第6期29卷 773-777页

作者： Caitlin Buck nathan Skillen jeanette Robertson Peter K.j.Robertson School of Chemistry and Chemical Engineering Queen's University Belfast School of Biological Sciences Queen's University Belfast Medical Biology Centre

The development of photocatalytic technology has grown significantly since its initial report and as such,a number of screening methods have been developed to assess activity. In the field of environmental remediation, a crucial factor is the formation of highly oxidising species such as OH radicals. These radicals are often the primary driving force for the removal and breakdown of organic and inorganic contaminants. The quantification of such compounds is challenging due to the nature of the radical,however indirect methods which deploy a chemical probe to essentially capture the radical have been shown to be effective. As discussed in the work presented here, optimisation of such a method is fundamental to the efficiency of the method. A starting concentration range of coumarin from 50 mmol/L to 1000 mmol/L was used along with a catalyst loading of 0.01 g/L to 1 g/L Ti TiO2 to identify that 250 mmol/L and 0.5 g/L Ti TiO2 were the optimum conditions for production. Under these parameters a maximum production rate of 35.91 mmol/L（Rmax= 0.4 mmol/L OH＊ min-1） was achieved which yielded at photonic efficiency of 4.88 OH＊moles photon-1 under UV irradiation. The data set presented also highlighted the limitations which are associated with the method which included; rapid exhaustion of the probe molecule and process inhibition through UV light saturation. Identifying both the optimum conditions and the potential limitations of the process were concluded to be key for the efficient deployment of the photocatalytic screening method.

关键词： Photocatalytic screening OH radical quantification Coumarin Environmental remediation Method optimisation

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

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：