The Experts below are selected from a list of 410811 Experts worldwide ranked by ideXlab platform
H. Wang - One of the best experts on this subject based on the ideXlab platform.
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Resilient ZnO nanowires In an irradiation environment: An In Situ Study
Acta Materialia, 2015Co-Authors: Cheng Sun, Blas P. Uberuaga, L. Yin, Youxing Chen, A. Kirk, Stuart A. Maloy, H. WangAbstract:Abstract ZnO nanowires (NWs) have been extensively studied for various device applications. Although these nanowires are often suspected to be impractical and highly unstable under hostile radiation environments, to date little is known on their radiation tolerance. Here, we show outstandIng resilience of ZnO NWs by usIng In Situ Kr ion irradiation at room temperature Inside a transmission electron microscope. Our studies show that ZnO nanowires with certaIn diameters become nearly immune to radiation damage due to the existence of dislocation loop denuded zones. A remarkable size effect also holds: the smaller the nanowire diameter, the lower the defect density. Rate theory modelIng suggests that the size effect arises from fast Interstitial migration and a limit In size to which Interstitial loops can grow. In Situ studies also revealed a surprisIng phenomenon: the pristIne prismatic loops can prevail over the strongest known defect sInks, free surfaces, to trap radiation-Induced defect clusters. This Study comprises the first critical step toward In-depth understandIng of radiation response of functional oxide nanowires for electronic device applications In extreme environments.
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In Situ Study of defect migration kInetics In nanoporous Ag with enhanced radiation tolerance
Scientific Reports, 2014Co-Authors: D. Bufford, Stuart A. Maloy, H. Wang, Y. Chen, M. A. Kirk, Y. Q. Wang, M. Li, X. ZhangAbstract:Defect sInks, such as graIn boundaries and phase boundaries, have been widely accepted to improve the irradiation resistance of metallic materials. However, free surface, an ideal defect sInk, has received little attention In bulk materials as surface-to-volume ratio is typically low. Here by usIng In Situ Kr ion irradiation technique In a transmission electron microscope, we show that nanoporous (NP) Ag has enhanced radiation tolerance. Besides direct evidence of free surface Induced frequent removal of various types of defect clusters, we determIned, for the first time, the global and Instantaneous diffusivity of defect clusters In both coarse-graIned (CG) and NP Ag. Opposite to conventional wisdom, both types of diffusivities are lower In NP Ag. Such a surprise is largely related to the reduced Interaction energy between isolated defect clusters In NP Ag. DetermInation of kInetics of defect clusters is essential to understand and model their migration and clusterIng In irradiated materials.
Stuart A. Maloy - One of the best experts on this subject based on the ideXlab platform.
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Resilient ZnO nanowires In an irradiation environment: An In Situ Study
Acta Materialia, 2015Co-Authors: Cheng Sun, Blas P. Uberuaga, L. Yin, Youxing Chen, A. Kirk, Stuart A. Maloy, H. WangAbstract:Abstract ZnO nanowires (NWs) have been extensively studied for various device applications. Although these nanowires are often suspected to be impractical and highly unstable under hostile radiation environments, to date little is known on their radiation tolerance. Here, we show outstandIng resilience of ZnO NWs by usIng In Situ Kr ion irradiation at room temperature Inside a transmission electron microscope. Our studies show that ZnO nanowires with certaIn diameters become nearly immune to radiation damage due to the existence of dislocation loop denuded zones. A remarkable size effect also holds: the smaller the nanowire diameter, the lower the defect density. Rate theory modelIng suggests that the size effect arises from fast Interstitial migration and a limit In size to which Interstitial loops can grow. In Situ studies also revealed a surprisIng phenomenon: the pristIne prismatic loops can prevail over the strongest known defect sInks, free surfaces, to trap radiation-Induced defect clusters. This Study comprises the first critical step toward In-depth understandIng of radiation response of functional oxide nanowires for electronic device applications In extreme environments.
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In Situ Study of defect migration kInetics In nanoporous Ag with enhanced radiation tolerance
Scientific Reports, 2014Co-Authors: D. Bufford, Stuart A. Maloy, H. Wang, Y. Chen, M. A. Kirk, Y. Q. Wang, M. Li, X. ZhangAbstract:Defect sInks, such as graIn boundaries and phase boundaries, have been widely accepted to improve the irradiation resistance of metallic materials. However, free surface, an ideal defect sInk, has received little attention In bulk materials as surface-to-volume ratio is typically low. Here by usIng In Situ Kr ion irradiation technique In a transmission electron microscope, we show that nanoporous (NP) Ag has enhanced radiation tolerance. Besides direct evidence of free surface Induced frequent removal of various types of defect clusters, we determIned, for the first time, the global and Instantaneous diffusivity of defect clusters In both coarse-graIned (CG) and NP Ag. Opposite to conventional wisdom, both types of diffusivities are lower In NP Ag. Such a surprise is largely related to the reduced Interaction energy between isolated defect clusters In NP Ag. DetermInation of kInetics of defect clusters is essential to understand and model their migration and clusterIng In irradiated materials.
Cheng Sun - One of the best experts on this subject based on the ideXlab platform.
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Resilient ZnO nanowires In an irradiation environment: An In Situ Study
Acta Materialia, 2015Co-Authors: Cheng Sun, Blas P. Uberuaga, L. Yin, Youxing Chen, A. Kirk, Stuart A. Maloy, H. WangAbstract:Abstract ZnO nanowires (NWs) have been extensively studied for various device applications. Although these nanowires are often suspected to be impractical and highly unstable under hostile radiation environments, to date little is known on their radiation tolerance. Here, we show outstandIng resilience of ZnO NWs by usIng In Situ Kr ion irradiation at room temperature Inside a transmission electron microscope. Our studies show that ZnO nanowires with certaIn diameters become nearly immune to radiation damage due to the existence of dislocation loop denuded zones. A remarkable size effect also holds: the smaller the nanowire diameter, the lower the defect density. Rate theory modelIng suggests that the size effect arises from fast Interstitial migration and a limit In size to which Interstitial loops can grow. In Situ studies also revealed a surprisIng phenomenon: the pristIne prismatic loops can prevail over the strongest known defect sInks, free surfaces, to trap radiation-Induced defect clusters. This Study comprises the first critical step toward In-depth understandIng of radiation response of functional oxide nanowires for electronic device applications In extreme environments.
Raj Suryanarayanan - One of the best experts on this subject based on the ideXlab platform.
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DetermInation of glass transition temperature and In Situ Study of the plasticizIng effect of water by Inverse gas chromatography.
Pharmaceutical Research, 2003Co-Authors: Rahul Surana, Linda Randall, Abira Pyne, N. Murti Vemuri, Raj SuryanarayananAbstract:Purpose. To use an Inverse gas chromatographic (IGC) method to determIne the glass transition temperature (Tg) of some amorphous pharmaceuticals and to extend this technique for the In Situ Study of the plasticizIng effect of water on these materials.
Marcella Esteves-oliveira - One of the best experts on this subject based on the ideXlab platform.
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Randomized In Situ Study on the efficacy of CO_2 laser irradiation In IncreasIng enamel erosion resistance
Clinical Oral Investigations, 2019Co-Authors: Karen Mueller Ramalho, Cp Eduardo, Nicole Heussen, Rodney Garcia Rocha, Hendrik Meyer-lueckel, Friedrich Lampert, Christian Apel, Marcella Esteves-oliveiraAbstract:Objectives The aim of this double-blInd, randomized In Situ Study was to evaluate the erosion-preventive effect of a specific set of CO_2 laser parameters, associated or not with fluoride . Methods Two hundred forty bovIne enamel blocks were prepared for Individual palatal appliances ( n = 6 samples/appliance). The Study had four phases of 5 days each, with ten volunteers and the followIng treatments: CO_2 laser irradiation (L), fluoride treatment (F), combIned fluoride and laser treatment (FL), and no treatment, control (C). Laser irradiation was performed at 0.3 J/cm^2 (5 μs/226 Hz/10.6 μm) and the fluoride gel contaIned AmF/NaF (12′500 ppm F^−/pH = 4.8–6). For erosive demIneralization, the appliances were immersed extra-orally In citric acid (0.05 M/20 mIn/pH = 2.3) twice daily. Analysis of enamel surface loss was done usIng a 3D-laser profilometer on 3 days. Additionally, fluoride uptake was quantified and scannIng electron microscopies were done. Data were analyzed with repeated measures ANOVA and post hoc pairwise comparisons (α = 0.05). Results At all analyzIng days, both laser groups caused the lowest means of enamel loss, which were also statistically significant lower than C ( p
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Randomized In Situ Study on the efficacy of CO2 laser irradiation In IncreasIng enamel erosion resistance.
Clinical Oral Investigations, 2018Co-Authors: Karen Mueller Ramalho, Cp Eduardo, Nicole Heussen, Rodney Garcia Rocha, Hendrik Meyer-lueckel, Friedrich Lampert, Christian Apel, Marcella Esteves-oliveiraAbstract:Objectives The aim of this double-blInd, randomized In Situ Study was to evaluate the erosion-preventive effect of a specific set of CO2 laser parameters, associated or not with fluoride.
