The Experts below are selected from a list of 198 Experts worldwide ranked by ideXlab platform
Filipe Vilela - One of the best experts on this subject based on the ideXlab platform.
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Continuous-flow synthesis and application of polymer-supported BODIPY Photosensitisers for the generation of singlet Oxygen; Process optimised by in-line NMR spectroscopy
Journal of Flow Chemistry, 2020Co-Authors: Christopher G. Thomson, Callum M. S. Jones, Georgina Rosair, David Ellis, Jose Marques-hueso, Filipe VilelaAbstract:Commercial polystyrene Merrifield-type resins have been post-synthetically functionalised with BODIPY photosensitisers via a novel aryl ester linking strategy in continuous-flow. A unique synthetic advantage of post-synthetically modifying heterogeneous materials in flow was identified. The homogeneous analogues of the polymer-supported BODIPYs were synthesised and used as reference to assess photophysical properties altered by the polymer-support and linker. The homogeneous and polymer-supported BODIPYs were applied in visible-light photosensitisation of singlet Oxygen for the conversion of α -terpinene to ascaridole. Materials produced in flow were superior to batch in terms of functional loading and photosensitisation efficiency. Flow photochemical reactions generally outperformed batch by a factor of 4 with respect to rate of reaction. The polymer-supported BODIPY resins could be irradiated for 96 h without loss of photosensitising ability. Additional material synthetic modification and conditions optimisation using an in-line NMR spectrometer resulted in a 24-fold rate enhancement from the initial material and conditions. Graphical abstract Glow with the flow! Metal-free synthesis of polymer-supported BODIPY photosensitisers in flow has been achieved and shown to be superior to conventional batch synthesis. The materials were successfully applied as visible light (>500 nm) photosensitisers for the production of singlet Oxygen and could be recycled multiple times. Pressure and flow rate optimisation was guided by in-line 1H-NMR spectroscopy leading to significant enhancement in Process efficiency.
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Continuous-flow synthesis and application of polymer-supported BODIPY Photosensitisers for the generation of singlet Oxygen; Process optimised by in-line NMR spectroscopy
Journal of Flow Chemistry, 2020Co-Authors: Christopher G. Thomson, Callum M. S. Jones, Georgina Rosair, David Ellis, Jose Marques-hueso, Ai-lan Lee, Filipe VilelaAbstract:Commercial polystyrene Merrifield-type resins have been post-synthetically functionalised with BODIPY photosensitisers via a novel aryl ester linking strategy in continuous-flow. A unique synthetic advantage of post-synthetically modifying heterogeneous materials in flow was identified. The homogeneous analogues of the polymer-supported BODIPYs were synthesised and used as reference to assess photophysical properties altered by the polymer-support and linker. The homogeneous and polymer-supported BODIPYs were applied in visible-light photosensitisation of singlet Oxygen for the conversion of α-terpinene to ascaridole. Materials produced in flow were superior to batch in terms of functional loading and photosensitisation efficiency. Flow photochemical reactions generally outperformed batch by a factor of 4 with respect to rate of reaction. The polymer-supported BODIPY resins could be irradiated for 96 h without loss of photosensitising ability. Additional material synthetic modification and conditions optimisation using an in-line NMR spectrometer resulted in a 24-fold rate enhancement from the initial material and conditions.
Bahram Jalali - One of the best experts on this subject based on the ideXlab platform.
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Add-drop filters utilizing vertically coupled microdisk resonators in silicon
Applied Physics Letters, 2005Co-Authors: Prakash Koonath, Tejaswi K. Indukuri, Bahram JalaliAbstract:Add-drop filters, based on vertically coupled microdisk resonators, have been realized in silicon, using a modified separation by implantation of Oxygen Process. Buried rib waveguides in the bottom-layer silicon, of a two-layer structure, are coupled to microdisk resonators in the top-layer silicon through a silicon dioxide layer formed by Oxygen implantation. The radii of the microdisk structures were varied suitably to obtain resonators with slightly shifted resonance wavelengths. The average adjacent channel crosstalk suppression of these filters exhibits an upper limit of 12.11dB and a lower limit of 6.2dB over the wavelength band under consideration.
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Vertically-coupled micro-resonators realized usingthree-dimensional sculpting in silicon
Applied Physics Letters, 2004Co-Authors: Prakash Koonath, Tejaswi K. Indukuri, Bahram JalaliAbstract:A modified separation by implantation of Oxygen Process has been developed to sculpt vertically coupled microdisk resonators in silicon. The approach involves the implantation of Oxygen ions into a silicon substrate, patterned with thermal oxide, to define waveguides on the bottom silicon layer, and photolithography and reactive ion etching to define the microdisk resonators on the top silicon layer. The top and the bottom silicon layers are separated by the oxide layer that was formed after the Oxygen implantation. Fabricated microdisk resonators show resonances with a Q value of 10 300 and a free spectral range of 5.4nm.
Christopher G. Thomson - One of the best experts on this subject based on the ideXlab platform.
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Continuous-flow synthesis and application of polymer-supported BODIPY Photosensitisers for the generation of singlet Oxygen; Process optimised by in-line NMR spectroscopy
Journal of Flow Chemistry, 2020Co-Authors: Christopher G. Thomson, Callum M. S. Jones, Georgina Rosair, David Ellis, Jose Marques-hueso, Filipe VilelaAbstract:Commercial polystyrene Merrifield-type resins have been post-synthetically functionalised with BODIPY photosensitisers via a novel aryl ester linking strategy in continuous-flow. A unique synthetic advantage of post-synthetically modifying heterogeneous materials in flow was identified. The homogeneous analogues of the polymer-supported BODIPYs were synthesised and used as reference to assess photophysical properties altered by the polymer-support and linker. The homogeneous and polymer-supported BODIPYs were applied in visible-light photosensitisation of singlet Oxygen for the conversion of α -terpinene to ascaridole. Materials produced in flow were superior to batch in terms of functional loading and photosensitisation efficiency. Flow photochemical reactions generally outperformed batch by a factor of 4 with respect to rate of reaction. The polymer-supported BODIPY resins could be irradiated for 96 h without loss of photosensitising ability. Additional material synthetic modification and conditions optimisation using an in-line NMR spectrometer resulted in a 24-fold rate enhancement from the initial material and conditions. Graphical abstract Glow with the flow! Metal-free synthesis of polymer-supported BODIPY photosensitisers in flow has been achieved and shown to be superior to conventional batch synthesis. The materials were successfully applied as visible light (>500 nm) photosensitisers for the production of singlet Oxygen and could be recycled multiple times. Pressure and flow rate optimisation was guided by in-line 1H-NMR spectroscopy leading to significant enhancement in Process efficiency.
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Continuous-flow synthesis and application of polymer-supported BODIPY Photosensitisers for the generation of singlet Oxygen; Process optimised by in-line NMR spectroscopy
Journal of Flow Chemistry, 2020Co-Authors: Christopher G. Thomson, Callum M. S. Jones, Georgina Rosair, David Ellis, Jose Marques-hueso, Ai-lan Lee, Filipe VilelaAbstract:Commercial polystyrene Merrifield-type resins have been post-synthetically functionalised with BODIPY photosensitisers via a novel aryl ester linking strategy in continuous-flow. A unique synthetic advantage of post-synthetically modifying heterogeneous materials in flow was identified. The homogeneous analogues of the polymer-supported BODIPYs were synthesised and used as reference to assess photophysical properties altered by the polymer-support and linker. The homogeneous and polymer-supported BODIPYs were applied in visible-light photosensitisation of singlet Oxygen for the conversion of α-terpinene to ascaridole. Materials produced in flow were superior to batch in terms of functional loading and photosensitisation efficiency. Flow photochemical reactions generally outperformed batch by a factor of 4 with respect to rate of reaction. The polymer-supported BODIPY resins could be irradiated for 96 h without loss of photosensitising ability. Additional material synthetic modification and conditions optimisation using an in-line NMR spectrometer resulted in a 24-fold rate enhancement from the initial material and conditions.
Prakash Koonath - One of the best experts on this subject based on the ideXlab platform.
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Add-drop filters utilizing vertically coupled microdisk resonators in silicon
Applied Physics Letters, 2005Co-Authors: Prakash Koonath, Tejaswi K. Indukuri, Bahram JalaliAbstract:Add-drop filters, based on vertically coupled microdisk resonators, have been realized in silicon, using a modified separation by implantation of Oxygen Process. Buried rib waveguides in the bottom-layer silicon, of a two-layer structure, are coupled to microdisk resonators in the top-layer silicon through a silicon dioxide layer formed by Oxygen implantation. The radii of the microdisk structures were varied suitably to obtain resonators with slightly shifted resonance wavelengths. The average adjacent channel crosstalk suppression of these filters exhibits an upper limit of 12.11dB and a lower limit of 6.2dB over the wavelength band under consideration.
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Vertically-coupled micro-resonators realized usingthree-dimensional sculpting in silicon
Applied Physics Letters, 2004Co-Authors: Prakash Koonath, Tejaswi K. Indukuri, Bahram JalaliAbstract:A modified separation by implantation of Oxygen Process has been developed to sculpt vertically coupled microdisk resonators in silicon. The approach involves the implantation of Oxygen ions into a silicon substrate, patterned with thermal oxide, to define waveguides on the bottom silicon layer, and photolithography and reactive ion etching to define the microdisk resonators on the top silicon layer. The top and the bottom silicon layers are separated by the oxide layer that was formed after the Oxygen implantation. Fabricated microdisk resonators show resonances with a Q value of 10 300 and a free spectral range of 5.4nm.
Rebecca Cortez - One of the best experts on this subject based on the ideXlab platform.
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Reactive sputter-deposition of Oxygenated amorphous carbon thin films in Ar/O2
Diamond and Related Materials, 2011Co-Authors: Travis Mckindra, Matthew J. O'keefe, Rebecca CortezAbstract:Abstract Oxygenated amorphous carbon thin films were deposited by DC magnetron sputtering using various argon and Oxygen Process gas mixtures. The X-ray diffraction data indicated that the predominantly amorphous films had more defined peaks with a higher partial pressure of Oxygen. Results indicated that use of Oxygen in the working gas enhanced the crystalline nature of the films. Scanning electron and atomic force microscopy revealed that the surface roughness and film topography differed with the Oxygen Process gas variations. X-ray photoelectron spectroscopy revealed increased surface Oxygen content with higher Oxygen concentration in the working gas. Raman spectroscopy results suggested that the increased Oxygen in the films may have led to a higher percentage of sp 3 -bonded carbon atoms. The growth rate (deposition rate) of the films decreased as the amount of Oxygen increased. This decreased deposition rate was associated with an Oxygen etching of the film.
