检索结果-南通市图书馆

Heavy ion ranges from first-principles electron dynamics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2019年第1期5卷 799-805页

作者： Andrea E.Sand Rafi Ullah Alfredo A.correa Department of Physics University of HelsinkiP.O.Box 43FI-00014 HelsinkiFinland Quantum Simulations Group Lawrence Livermore National LaboratoryLivermoreCA 94550USA CIC nanoGUNE Ave.Tolosa 7620018 Donostia-San SebastiánSpain Departamento de Física de Materiales UPV/EHUPaseo Manuel de Lardizabal 320018 Donostia-San SebastiánSpain

The effects of incident energetic particles,and the modification of materials under irradiation,are governed by the mechanisms of energy losses of ions in *** complex processes affecting projectiles spanning many orders of magnitude in energy depend on both ion and electron *** multi-scale modeling methods that correctly capture the relevant processes is crucial for predicting radiation effects in diverse *** this work,we obtain channeling ion ranges for tungsten,a prototypical heavy ion,by explicitly simulating ion trajectories with a method that takes into account both the nuclear and the electronic stopping *** electronic stopping power of self-ion irradiated tungsten is obtained from first-principles timedependent density functional theory(TDDFT).Although the TDDFT calculations predict a lower stopping power than SRIM by a factor of three,our result shows very good agreement in a direct comparison with ion range *** results demonstrate the validity of the TDDFT method for determining electronic energy losses of heavy projectiles,and in turn its viability for the study of radiation damage.

关键词： stopping governed dynamics

Two-tiered reconstruction of Late Pleistocene to Holocene changes in the freezing level height in the largest glacierized areas of the Colombian Andes

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 Mountain Science 2022年第3期19卷 615-636页

作者： Daniel RUIZ-CARRASCAL Daniel GONZALEZ-DUQUE Isabel RESTREPO-correa Department of Ecology Evolution and Environmental BiologyColumbia University in the City of New YorkNew YorkNY 10027USA Department of Civil and Environmental Engineering Vanderbilt University40024th Avenue South269 Jacobs HallNashville TN 3720USA Department of Earth Sciences Universidad EAFITCarrera 49 No.7Sur-50MedellínColombia

One way of deducing vertical shifts in the altitudinal distribution of Colombian high-altitude páramo environments is by inferring fluctuations in the height of the local freezing *** our research,we are implementing two complementary approaches to reconstruct Late Pleistocene to Holocene changes in the freezing level height(FLH)in two of the most extensively glacier-covered areas of the northern *** combined remote sensing and field-based geomorphological mapping with time-series reconstruction of changes in the altitude of the 0°C *** in the FLH were based on alreadypublished~30 kyr paleo-reconstructions of sea surface temperatures(SSTs)of the eastern tropical Pacific and the western tropical Atlantic,as well as on reconstructed long-term sea level changes and empirical orthogonal functions of present-day(historical)Indo-Pacific and tropical Atlantic SST *** also analyzed the probability distribution of air-sea temperature differences and the spatial distribution of grid points with SSTs above the minimum threshold necessary to initiate deep *** considered available historical nearsurface and free air temperature data of ERA-Interim reanalysis products,General Circulation Model(GCM)simulations,weather stations,and(deployed by our group)digital sensors,to assess the normal Environmental Lapse Rates(ELRs)at the regional to local *** combined maps of glacial landforms and our reconstructed FLHs provided us with a wellfounded inference of potential past glacier advances,narrowing down the coarse resolution of ice margins suggested by previous research *** extent of the areas with temperatures below the freezing point suggested here for the summits of our main study site exceeds in magnitude the corresponding glacier icecaps and front advances proposed by previous ***,our average lowest altitudes of the FLH for our comparative site are consistently above the main glacier-front advances previously su

关键词： Glacial events Colombian Andes Climate reconstruction Geomorphology Mountain glaciers Freezing level height

Vascularization in interconnected 3D printed Ti-6Al-4V foams with hydrogel matrix for biomedical bone replacement implants

在线全文

学校读者我要写书评

暂无评论

Science China Materials 2018年第4期61卷 565-578页

作者： Victor L.correa Kristine M.Garza Lawrence E.Murr Department of Metallurgical Materials and Biomedical Engineering University of Texas at El Paso Department of Biological Sciences University of Texas at El Paso

Vascularization on newly implanted metal orthopedic implants has remained a challenge in the field of tissue engineering. To address this challenge, in this research,an interconnected foam structure of Ti-6 Al-4 V was microfabricated by electron beam melting(EBM) technique. The foam in question has a density of 1.77 g cm-3 with 60% porosity and a tensile strength of 18 GPa. An extracellular matrix based hydrogel was added as an aqueous matrix to the *** mimetic stress has been closely related to many wound healing biomedical applications as it increases survival and proliferation molecular signals. To that end, increased expression of hypoxia-inducible factor-1α(Hif-1α) and vascular endothelial growth factor(VEGF) in the aqueous hydrogel matrix was achieved by the addition of a hypoxia mimetic deferoxamine mesylate(DFM). In this study, the formation of an endothelial network was achieved in a hydrogel matrix in the presence of the before mentioned 3 D printed metal foam. Cellular viability, fluorescent microscopy and scanning electron microscopy imaging analysis demonstrate that pre-osteoblasts undergo proliferation and also attach efficiently to the foam when exposed to DFM. Human umbilical vascular endothelial cells(HUVECs) were grown in an extracellular matrix-like 3 D hydrogel and a hypoxia-like stress was achieved. This research demonstrates that pre-osteoblast cells undergo cell differentiation and increase the production of hydroxyapatite on exposure to the hypoxia mimetic molecule. This proposed approach encompasses an ideal prototype for a completely living implanted structure for future orthopedic implants.

关键词： Ti-6Al-4V electron beam melting angiogenesis deferoxamine mesylate hydrogel vascularization

＂Takeaway＂ drug delivery： A new nanomedical paradigm

在线全文

学校读者我要写书评

暂无评论

Nano Research 2017年第7期10卷 2234-2243页

作者： Elena Gonzalez-Domfnguez Benito Rodriguez-Gonzalez Moises Perez-Lorenzo Miguel A. correa-Duarte Department of Physical Chemistry Biomedical Research Center (CINBIO) and Southern Galicia Institute of Health Research (IISGS)Universidade de Vigo 36310 Vigo Spain

An alternative model to the well-established paradigm of the externally switchable drug delivery systems is herein proposed. In contrast to the on--off archetype, here the amount of released drug is pre-set by the application of an external stimulus, and is gradually released after the withdrawal of the exogenous signal. These attributes are achieved through an innovative approach featuring the integration of plasmonic nanovehicles in a polymer-based film. Such a platform is provided with optically responsive capabilities together with multiple diffusional barriers, allowing for an ＂on-demand＂ time-limited release where light acts as a therapeutic ＂starting shot＂. These nanoarchitectured depots have great potential as implantable drug delivery systems in clinical scenarios where a recurrent, sustained, and yet, on--off administration of medication is required. The application of these hybrid materials may extend the implementation of nanomedicine strategies beyond the point-of-care setting.

关键词： release plasmonic nanocapsule hydrogel near infrared (NIR)

Unsupervised full-color cellular image reconstruction through disordered optical fiber

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2023年第6期12卷 1091-1102页

作者： Xiaowen Hu Jian Zhao Jose Enrique Antonio-Lopez Rodrigo Amezcua correa Axel Schülzgen CREOL The College of Optics and PhotonicsUniversity of Central FloridaOrlandoFL 32816USA The Picower Institute for Learning and Memory Massachusetts Institute of TechnologyCambridgeMA 02139USA

Recent years have witnessed the tremendous development of fusing fiber-optic imaging with supervised deep learning to enable high-quality imaging of hard-to-reach ***,the supervised deep learning method imposes strict constraints on fiber-optic imaging systems,where the input objects and the fiber outputs have to be collected in *** unleash the full potential of fiber-optic imaging,unsupervised image reconstruction is in ***,neither optical fiber bundles nor multimode fibers can achieve a point-to-point transmission of the object with a high sampling density,as is a prerequisite for unsupervised image *** recently proposed disordered fibers offer a new solution based on the transverse Anderson ***,we demonstrate unsupervised full-color imaging with a cellular resolution through a meter-long disordered fiber in both transmission and reflection *** unsupervised image reconstruction consists of two *** the first stage,we perform a pixel-wise standardization on the fiber outputs using the statistics of the *** the second stage,we recover the fine details of the reconstructions through a generative adversarial *** image reconstruction does not need paired images,enabling a much more flexible calibration under various *** new solution achieves full-color high-fidelity cell imaging within a working distance of at least 4 mm by only collecting the fiber outputs after an initial *** imaging robustness is also demonstrated when the disordered fiber is bent with a central angle of 60°.Moreover,the cross-domain generality on unseen objects is shown to be enhanced with a diversified object set.

关键词： fiber optical image

Magnetic-gateable valley exciton emission

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2020年第1期6卷 915-923页

作者： Helena Bragança Hao Zeng Alexandre Cavalheiro Dias Jorge Huamani correa Fanyao Qu Instituto de Física Universidade de BrasíliaBrasília-DF 70919-970Brazil Departamento de Física Universidade Federal de Ouro PretoOuro PretoMinas Gerais 35400-000Brazil Department of Physics University at Buffalothe State University of New YorkBuffaloNY 14260USA

The use of valley excitonic states of transition metal dichalcogenides to store and manipulate information is hampered by fast carrier recombination and short valley *** propose theoretically a scheme to overcome such an obstacle,by applying a tilted exchange field through the magnetic proximity effect on monolayer MoS_(2).While the in-plane component of the exchange field brightens the dark exciton by spin mixing,the out-of-plane field can effectively gate the emission with an ON/OFF ratio of ***,the brightening is valley selective,leading to nearly 100% valley and spin polarization at room *** resulting strongly gateable dark-exciton emission with long lifetime and near unity valley polarization makes it convenient to manipulate the valley degree of freedom,which may offer new paradigm for information processing and transmission.

关键词： temperature overcome applying

Photovoltaic-based DC microgrid with partial shading and fault tolerance

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 Modern Power Systems and Clean Energy 2019年第2期7卷 340-349页

作者： Carlos correa-BETANZO Hugo CALLEJA Carlos AGUILAR Adolfo R.LOPEZ-NUNEZ Elías RODRIGUEZ Electronics Department National Center for Research and Development of Technology62490 CuernavacaMorelosMexico Electronics Department Technological Institute of Celaya38010 CelayaGuanajuatoMexico

Partial shading is a common problem that affects bus regulation in DC microgrids with several photovoltaic(PV) modules as energy sources, as a result of reduced solar irradiance reaching the *** problem can be mitigated by incorporating batteries, but if they are not included, appropriate control strategies must be used. This paper presents a new approach in a PV-based DC microgrid, which provides a high-quality bus voltage regulation in islanding mode, without being affected by partial shading or problems associated with PV module connection and disconnection. The solution proposed herein ensures a proper voltage regulation without being affected by problems such as failures in PV modules or mismatch between them. Besides, it can help to prevent PV partial shade stress by disconnecting the affected modules. A further advantage of the approach is the flexibility to connect more PV modules. The advantages of this approach were verified in a 200 W prototype.

关键词： Photovoltaic Microgrid Partial shading Fault Control strategy

Security-constrained model for integrated power and natural-gas system

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2017年第3期5卷 326-336页

作者： Carlos M.correa-POSADA Pedro SáNCHEZ-MARTíN Sara LUMBRERAS XM Compania de Expertos en MercadosMedellı´nColombia Technological Research Institute(IIT) ICAI School of EngineeringComillas Pontifical UniversityMadridSpain

One of the main factors impacting the reliability of energy systems nowadays is the growing interdependence between electricity and gas networks due to the increase in the installation of gas-fired units. Securityconstrained unit commitment(SCUC) models are used to economically schedule generating units without compromising the system reliability. This paper proposes a novel SCUC formulation that includes dynamic gas constraints,such as the line pack, and transmission contingencies in power and gas networks for studying the integrated system reliability. A Benders’ decomposition with linear programming techniques is developed to be able to study large systems. By including dynamic gas constraints into the SCUC, the proposed model accounts for the flexibility and reliability that power systems require from gas systems in the short term. Case studies of different size and complexity are employed to illustrate how the reliability of one system is affected by the reliability of the other. These experiments show how both systems operate in a secure way(by including contingencies) increases operating costs by approximately 9% and also show how these costs can vary by 24% depending on the line pack scheduling.

关键词： Benders’decomposition Natural gas Reliability Security-constrained unit commitment

Assessment of energy consumption,environmental effects and fuel costs of the bus rapid transit system in Bogotá(Colombia)

在线全文

学校读者我要写书评

暂无评论

Clean Energy 2024年第3期8卷 34-47页

作者： Jhon Jairo Pérez Luis Hernando correa Poul AlbergØstergaard Pedro Cabrera Universidad de La Salle-Engineering Faculty Electrical DepartmentCampus La CandelariaBogota D.C.Colombia Aalborg University Department of PlanningRendsburggade 149000 AalborgDenmark University of Las Palmas de Gran Canaria Department of Mechanical EngineeringCampus Universitario de TafiraLas Palmas de Gran CanariaSpain

Colombia aims to boost the utilization of mass transportation systems in its major cities while simultaneously reducing greenhouse gas emissions by 20%,in alignment with the commitments of the COP21 *** 2020,the transport sector in Colombia accounted for 34.4%of the country’s energy demand and was responsible for~49%of its total CO_(2) *** article presents an assessment of energy consumption,environmental effects and the fuel costs of Bogotá’s bus rapid transit system based on the Activity,Share,Intensity,Fuel methodology.A long-term analysis spanning from 2021 to 2040 was developed using the long-range energy alternatives planning *** conduct this assessment,the tool was calibrated using data from 2019 and *** distinct scenarios based on energy policies implemented in Bogotáwere examined:Business as Usual,Fast Transition,High Growth and Low *** energy consumption and environmental effects,the results underscore the pivotal role of diversifying energy sources and reducing reliance on fossil fuels such as ***,the analysis emphasizes the urgent need to accelerate the transition to alternative energy sources such as natural gas and electricity.

关键词： ASIF energy consumption environmental effects LEAP long-term energy model public transport