500 research outputs found
Investigation of how the chemical and physical properties of thermally evaporated SnS vary with source and substrate temperatures
Annealing studies and electrical properties of SnS-based solar cells
Thin films of SnS (tin sulphide) were thermally evaporated onto glass and CdS/ITO (cadmium sulphide/indium tin oxide) coated glass substrates and then annealed in vacuum with the aim of optimising them for use in photovoltaic solar cell device structures. The chemical and physical properties of the layers were determined using scanning electron microscopy, energy dispersive x-ray analysis, x-ray diffraction, and transmittance versus wavelength measurements. “Superstrate configuration” devices were also made using indium tin oxide as the transparent conductive oxide, thermally evaporated cadmium sulphide as the buffer layer and evaporated copper/indium as the back contact material. Capacitance-voltage data are given for the fabricated devices. Capacitance- voltage, spectral response and I-V data are given for the fabricated devices
Towards all-order factorization of QED amplitudes at next-to-leading power
We generalise the factorization of abelian gauge theory amplitudes to
next-to-leading power (NLP) in a soft scale expansion, following a recent
generalisation for Yukawa theory. From an all-order power counting analysis of
leading and next-to-leading regions, we infer the factorized structure for both
a parametrically small and zero fermion mass. This requires the introduction of
new universal jet functions, for non-radiative and single-radiative QED
amplitudes, which we compute at one-loop order. We show that our factorization
formula reproduces the relevant regions in one- and two-loop scattering
amplitudes, appropriately addressing endpoint divergences. It provides a
description of virtual collinear modes and accounts for non-trivial
hard-collinear interplay present beyond the one-loop level, making this a first
step towards a complete all-order factorization framework for gauge-theory
amplitudes at NLP.Comment: 31 pages, 18 figures. v2: as in journal versio
Life cycle assessment of the biofuel production from lignocellulosic biomass in a hydrothermal liquefaction - aqueous phase reforming integrated biorefinery
The use of biofuels in the transport sector is one of the strategies for its decarbonization. Here, the LCA meth-odology was used for the first time to assess the environmental impacts of a biorefinery where hydrothermal liquefaction (HTL) and aqueous phase reforming (APR) were integrated. This novel coupling was proposed to valorize the carbon loss in the HTL-derived aqueous phase, while simultaneously reducing the external H2 de-mand during biocrude upgrading. Corn stover (residue) and lignin-rich stream (waste) were evaluated as possible lignocellulosic feedstocks. The global warming potential (GWP) was 56.1 and 58.4 g CO2 eq/MJbiofuel, respec-tively. Most of the GWP was attributable to the electrolysis step in the lignin-rich stream case and to the thermal duty and platinum use in the corn stover case. Other impact categories were investigated, and an uncertainty analysis was also carried out. A sensitivity analysis on biogenic carbon, electricity/thermal energy source and alternative hydrogen supply was conducted to estimate their influence on the GWP. Finally, the two scenarios were compared with the environmental impact of fossil-and other biomass-derived fuels, also considering fuel utilization. HTL-APR allowed a 37% reduction compared to fossil diesel, further reduced to 80% with the lignin -rich stream when green energy was used
Glutathione-Induced Release of Zeatin From Functionalized Gold Nanovectors
The paper shows our preliminary results on the different spectroscopic behavior of three types of gold nanoparticles (obtained respectively by chemical synthesis, laser ablation in pure water and laser ablation in a citrate solution) modified with trans-zeatin, a plant growth regulator, in presence of glutathione. The reaction of ligand substitution of the adsorbed zeatin with glutathione is studied through surface enhanced Raman spectroscopy and is revealed to occur only when citrate-laser ablated gold nanoparticles are employed, making these particles potentially good candidates as vehicles of zeatin inside plant cells for future agricultural applications
Glutathione-Induced Release of Zeatin From Functionalized Gold Nanovectors
The paper shows our preliminary results on the different spectroscopic behavior of three types of gold nanoparticles (obtained respectively by chemical synthesis, laser ablation in pure water and laser ablation in a citrate solution) modified with trans-zeatin, a plant growth regulator, in presence of glutathione. The reaction of ligand substitution of the adsorbed zeatin with glutathione is studied through surface enhanced Raman spectroscopy and is revealed to occur only when citrate-laser ablated gold nanoparticles are employed, making these particles potentially good candidates as vehicles of zeatin inside plant cells for future agricultural applications
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