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Nano Research 2020年第5期13卷 1465-1471页

作者： thomas A.Celano Seokhyoung Kim David j.Hill james F.Cahoon Department of Chemistry University of North Carolina at Chapel HillChapel HillNC 27599-3290USA

Bottom-up synthesis of semiconductor nanowires(NWs)by the vapor-liquid-solid(VLS)mechanism has enabled diverse technological applications for these *** metallic NWs,however,it has been challenging to form large-area interconnected NW ***,we generate centimeter-scale meshes of mechanically and electrically interconnected Si NWs by sequentially growing,collapsing,and joining the NWs using a capillarity-driven welding *** fabricate meshes from VLS-grown NWs ranging in diameter from 20 to 100 nm and find that the meshes are three-dimensional with a thickness ranging from^1 to^10 microns depending on the NW *** extinction measurements reveal that the networks are semi-transparent with a color that depends on the absorption and scattering characteristics of individual ***,active voltage contrast imaging of both centimeter-and micron-scale meshes reveals widespread electrical *** a sacrificial layer,we demonstrate that the mesh can be liberated from the growth substrate,yielding a highly flexible and transparent *** transport measurements both on the growth substrate and on liberated,flexible films reveal electrical conduction across a centimeter scale with a sheet resistance of^160-180 kΩ/square that does not change significantly upon *** the ability to encode complex functionality in semiconductor NWs through the VLS process,we believe these meshes of networked NWs could find application as neuromorphic memory,electrode scaffolds,and bioelectronic interfaces.

关键词： semiconductor nanowire conductive network flexible electronics welding thermal annealing active-voltage contrast

Bemisia tabaci （Hemiptera： Aleyrodidae） nymphal feeding in cotton （Gossypium hirsutum） leaves

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Insect Science 2007年第5期14卷 375-381页

作者： CHANG-CHI CHU DENNIS A. MARGOSAN jAMES S. BUCKNER thomas P. FREEMAN thomas j. HENNEBERRY USDA ARS US Arid Land Agricultural Research Center Maricopa Arizona USDA ARS San Joaquin Valley Agricultural Science Center Parlier California Biosciences Research Laboratory Fargo North Dakota Electron Microscopy Center North Dakota State University Fargo North Dakota USA

We used brightfield electron microscopy （BEM）, differential interference contrast microscopy （DICM）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, and confocal laser scanning microscopy （CLSM） to investigate the stylet pathways of Bemisia tabaci during nymphal feeding behavior in cotton leaves beginning with penetration of the abaxial leaf surface and ending with stylets in sieve tubes in phloem tissues. Most nymphal stylets within salivary sheaths penetrating leaf tissues made complex turns and developed more than one salivary sheath branch before ending in sieve tubes. The external morphology of the salivary sheaths and their routes between and through leaf cells are described during the present study. Results showed the presence of the stylet within the sieve tubes. B. tabaci nymphs may remove stylets and feed in different sieve tubes. Ten short movies showing the progression of the stylet penetrations from adaxial surface to the sieve tubes are attached to Figures 8-15. The report and movies can be viewed from the internet. Download the movies to a local drive in your computer first for fast upload. The movies are posted on the website http：//***/Services/***？docid=14629. The movies can be used as a teaching aid in biology classes.

关键词： Bemisia tabaci microscopy nymphs feeding stylet sheath stylet

Use of Intermetallic Alloys as Reactive Materials for Warhead Applications

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火炸药学报 2015年第6期38卷 8-10页

作者： jürgen Evers thomas M.Klaptke Department of Chemistry Energetic Materials ResearchLMU Munich

With this communication we want to suggest the system ZrW2,a high-density and very hard intermetallic compound that reacts/burns highly exothermic with air at high *** intermetallic phase should provide a very suitabl... 详细信息

关键词： Cermisch metal intermetallic phase thermites reactive structure material warhead

INCIDENCE MATRIX APPROACH FOR CALCULATING READINESS LEVELS

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journal of Systems Science and Systems Engineering 2014年第4期23卷 377-403页

作者： Mark A.London thomas H.Holzer Timothy j.Eveleigh Shahryar Sarkani School of Engineering and Applied Science George Washington University

Contemporary system maturity assessment approaches have failed to provide robust quantitative system evaluations resulting in increased program costs and developmental *** assessment metrics,such as Technology Readiness Levels（TRL）,do not sufficiently evaluate increasingly complex *** System Readiness Level（SRL）is a newly developed system development metric that is a mathematical function of TRL and Integration Readiness Level（IRL） values for the components and connections of a particular *** acceptance has been hindered because of concerns over SRL mathematical operations that may lead to inaccurate system readiness *** inaccurate system readiness assessments are called readiness reversals.A new SRL calculation method using incidence matrices is proposed to alleviate these mathematical *** presence of SRL readiness reversal is modeled for four SRL calculation methods across several system *** regression analysis demonstrates that the proposed Incidence Matrix SRL（IMSRL）method has a decreased presence of readiness reversal than other approaches suggested in the *** SRL methods will foster greater SRL adoption by systems engineering professionals and will support system development risk reduction goals.

关键词： Technology Readiness Level(TRL) integration readiness level(IRL) system readiness level(SRL) system readiness graph theory systems engineering

Skin and composite grafts

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Plastic and Aesthetic Research 2022年第1期9卷 455-465页

作者： Katherine Hicks j.Regan thomas Department of Otolaryngology Head&Neck Surgery University of Texas Medical BranchGalvestonTX 77019USA Department of Otolaryngology Head&Neck Surgery Northwestern McGaw Medical CenterChicagoIL 60611USA

Skin grafts may be used for coverage of facial defects in situations in which alternative methods of reconstruction,such as local flaps,are not an *** may also be beneficial for patients who wish to avoid or who are not good candidates for more complex ***-thickness skin grafts often have a better color and texture match to adjacent skin when compared to split-thickness grafts;however,split-thickness grafts have lower metabolic demand and increased survival *** grafts may be very useful in the repair of defects with unique contour and support requirements,such as the nasal ala and *** all grafts,thoughtful planning and sound surgical technique are critical in achieving the best possible functional and aesthetic result.

关键词： Split-thickness skin grafts full-thickness skin grafts composite grafts nasal reconstruction eyelid reconstruction

Atomic and Close-to-Atomic Scale Manufacturing:A Review on Atomic Layer Removal Methods Using Atomic Force Microscopy

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Nanomanufacturing and Metrology 2020年第3期3卷 167-186页

作者： Paven thomas Mathew Brian j.Rodriguez Fengzhou Fang Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin D04V1W8Ireland School of Physics University College DublinBelfieldDublin D04 V1W8Ireland Conway Institute of Biomolecular and Biomedical Research University College DublinBelfield.Dublin D04V1W8Ireland State Key Laboratory of Precision Measuring Technology and Instruments Centre of Micro/Nano Manufacturing TechnologyMNMT.Tianjin UniversityTianjin 300072China

Manufacturing at the atomic scale is the next generation of the industrial *** and close-to-atomic scalemanufacturing(ACSM)helps to achieve *** force microscopy(AFM)is a promising method for this purposesince an instrument to machine at this small scale has not yet been *** the need for increasing the number ofelectronic components inside an integrated circuit chip is emerging in the present-day scenario,methods should be adoptedto reduce the size of connections inside the *** can be achieved using ***,connecting moleculeswith the electrodes and then to the external world is *** must be laid to make this possible for *** layer removal,down to one atom,can be employed for this ***,theoretical works are beingperformed extensively to study the interactions happening at the molecule-electrode junction,and how electronic transportis affected by the functionality and robustness of the *** theoretical studies can be verified experimentally only if nano electrodes are *** is widely used in the semiconductor industry to fabricate electronic ***,carbon-based materials such as highly oriented pyrolytic graphite,gold,and silicon carbide find applications inthe electronic device manufacturing ***,ACSM of these materials should be developed *** paperpresents a review on the state-of-the-art research performed on material removal at the atomic scale by electrochemical andmechanical methods of the mentioned materials using AFM and provides a roadmap to achieve effective mass productionof these devices.

关键词： Atomic force microscopy Atomic-scale manufacturing Molecular scale devices Electrochemistry ACSM ManufacturingⅢ

Geochronological constraints on the metamorphic sole of the Semail ophiolite in the United Arab Emirates

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Geoscience Frontiers 2016年第4期7卷 609-619页

作者： Nick M.W.Roberts Robert j.thomas joachim jacobs NERC Isotope Geosciences Laboratory British Geological SurveyKeyworthNG12 5GGUK Council for Geoscience P.O.Box 572Bellville 7535South Africa University of Bergen.Department of Earth Science PB 78035020 BergenNorway Norwegian Polar Institute Fram Centre9296 TromsoNorway

The Semail ophiolite of Oman and the United Arab Emirates （UAE） provides the best preserved large slice of oceanic lithosphere exposed on the continental crust, and offers unique opportunities to study processes of ocean crust formation, subduction initiation and obduction. Metamorphic rocks exposed in the eastern UAE have traditionally been interpreted as a metamorphic sole to the Semail ophiolite. However, there has been some debate over the possibility that the exposures contain components of older Arabian continental crust. To help answer this question, presented here are new zircon and futile U-Pb geochronological data from various units of the metamorphic rocks. Zircon was absent in most samples. Those that yielded zircon and futile provide dominant single age populations that are 95-93 Ma, partially overlapping with the known age of oceanic crust formation （96.5-94.5 Ma）, and partially overlapping with cooling ages of the metamorphic rocks （95 90 Ma）. The data are interpreted as dating high-grade metamorphism during subduction burial of the sediments into hot mantle lithosphere, and rapid cooling during their subsequent exhumation. A few discordant zircon ages, interpreted as late Neoproterozoic and younger, represent minor detrital input from the continent. No evidence is found in favour of the existence of older Arabian continental crust within the metamorphic rocks of the UAE.

关键词： Semail ophiolite United Arab Emirates Metamorphic sole U-Pb geochronology Zircon Rutile

Crystallization Study of Cu_(56)Zr_7Ti_(37) Metallic Glass by Electrical Resistivity Measurement

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journal of Materials Science & Technology 2011年第3期27卷 275-279页

作者： Ansu j.Kailath Kalpalata Dutta thomas C. Alex Amitava Mitra National Metallurgical Laboratory

In this paper, the crystallization behaviour of amorphous Cu56Zr7Ti37 alloy using thermal electrical resistivity （TER） and differential scanning calorimetry （DSC） studies has been described. Isochronal TER and DSC measurements indicate that crystallization occurs in two stages. Isothermal crystallization studies of the alloy by TER show that the kinetics conforms to johnson-Mehl-Avrami model. Avrami exponents derived from kinetics, between 1.1 and 1.2, imply that the crystallization processes are diffusion controlled with near zero nucleation. Activation energy has been found to increase with the transformed volume fraction. A plausible explanation has been presented by separating the contributions due to nucleation and crystal growth towards total activation energy.

关键词： Metallic glass Crystallization Electrical resistivity Avrami exponent Activation energy

Improved Interleaved Single-Ended Primary Inductor-Converter forSingle-Phase Grid-Connected System

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Intelligent Automation & Soft Computing 2023年第3期35卷 3459-3478页

作者： T.j.thomas Thangam K.Muthu Vel Noorul Islam Centre for Higher Education Nagarkovil629180TamilnaduIndia

The generation of electricity based on renewable energy sources,parti-cularly Photovoltaic(PV)system has been greatly increased and it is simply insti-gated for both domestic and commercial *** power generated from the PV system is erratic and hence there is a need for an efﬁcient converter to perform the extraction of maximum *** improved interleaved Single-ended Primary Inductor-Converter(SEPIC)converter is employed in proposed work to extricate most of power from renewable *** proposed converter minimizes ripples,reduces electromagnetic interference due toﬁlter elements and the contin-uous input current improves the power output of PV panel.A Crow Search Algo-rithm(CSA)based Proportional Integral(PI)controller is utilized for controlling the converter switches effectively by optimizing the parameters of PI *** optimized PI controller reduces ripples present in Direct Current(DC)vol-tage,maintains constant voltage at proposed converter output and reduces over-shoots with minimum settling and rise *** voltage is given to single phase grid via 1�Voltage Source Inverter(VSI).The command pulses of 1�VSI are produced by simple PI *** response of the proposed converter is thus improved with less input *** implementing CSA based PI the efﬁciency of proposed converter obtained is 96%and the Total Harmonic Distor-tion(THD)is found to be 2:4%.The dynamics and closed loop operation is designed and modeled using MATLAB Simulink tool and its behavior is performed.

关键词： Improved interleaved DC-DC SEPIC converter crow search algorithm PI controller voltage source inverter PV array single phase grid

Regional climate model downscaling may improve the prediction of alien plant species distributions

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Frontiers of Earth Science 2014年第4期8卷 457-471页

作者： Shuyan LIU Xin-Zhong LIANG Wei GAO thomas j. STOHLGREN Earth System Science Interdisciplinary Center University of Maryland College Park MD 20740 USA Department of Atmospheric and Oceanic Sciences University of Maryland College Park MD 20740 USA Department of Ecosystem Science and Sustainability Colorado State University Fort Collins CO 80523 USA Fort Collins Science Center U.S. Geological Survey Fort Collins CO 80526 USA

Distributions of invasive species are commonly predicted with species distribution models that build upon the statistical relationships between observed species presence data and climate data. We used field observations, climate station data, and Maximum Entropy species distribution models for 13 invasive plant species in the United States, and then compared the models with inputs from a General Circulation Model （hereafter GCM-based models） and a downscaled Regional Climate Model （hereafter, RCM-based models）. We also compared species distributions based on either GCM-based or RCM-based models for the present （1990-1999） to the future （2046- 2055）. RCM-based species distribution models replicated observed distributions remarkably better than GCM- based models for all invasive species under the current climate. This was shown for the presence locations of the species, and by using four common statistical metrics to compare modeled distributions. For two widespread invasive taxa （Bromus tectorum or cheatgrass, and Tamarix spp. or tamarisk）, GCM-based models failed miserably to reproduce observed species distributions. In contrast, RCM-based species distribution models closely matched observations. Future species distributions may be significantly affected by using GCM-based inputs. Because invasive plants species often show high resilience and low rates of local extinction, RCM-based species distribution models may perform better than GCM-based species distribution models for planning containment programs for invasive species.

关键词： climate change species distribution model,Maxent downscaling