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1.
Heliyon ; 10(3): e25839, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38356569

RESUMO

This paper provides an evaluation of a 4-kW grid-connected full-bridge PV inverter under three different scenarios to assess its reliability with a fixed PV degradation rate, with a climate-based degradation rate, and without considering PV degradation. The climate-based degradation rates are estimated using a physics-based model that considers the different parameters influencing the PV reliability. Three different locations representing three different climate zones (hot and dry, hot and humid, and moderate climates) have been chosen in this study. The estimated lifetime of the IGBT, the switching device in the PV inverter, varies depending on the location, with the inclusion of fixed and climate-based degradation rates extending the lifespan of the PV inverter in the examined locations. The results demonstrate the significant impact of PV climate-based degradation rates on power electronics' reliability assessment and the importance of considering various factors in predicting device failures. To ensure the PV inverter's lifespan over the desired period in areas with high solar irradiation rates and extremely hot climates, the design parameters should be slightly elevated above the standard value.

2.
Chemistry ; 26(42): 9070-9083, 2020 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-32026520

RESUMO

Solution-based (multi)metal oxide synthesis has been carried out employing a large diversity of precursor routes. The selection of an appropriate synthesis strategy is frequently dictated by the resulting material properties, although this choice should also be based on green chemistry principles, atom economy considerations and energy efficiency. In order to limit the required energy budget to convert the chemical precursor to the target oxide material, various approaches were recently reported. This Review summarizes some frequently encountered low-temperature routes, critically assessing their application window and advantages. More specifically, auto-combustion synthesis, UV-assisted decomposition routes, sol-gel network adjustments and precursor complex design concepts are discussed. It is expected that this toolbox of low-temperature strategies may assist further progress in the field, stimulating novel applications, such as flexible electronics or organic-oxide hybrid materials, which are very sensitive to the temperature requirements.

3.
J Nanosci Nanotechnol ; 9(6): 3483-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19504872

RESUMO

Detecting nano-gram quantities of analyte in the liquid or gas phase is crucial for pathogen detection, antigen/DNA detection, water monitoring, electrochemical analysis, and many other bio-electrochemical applications. The quartz crystal microbalance (QCM) has become a significant sensor for both liquid and gas phase graviometry due to its high sensitivity, robustness, ease of use and simultaneous electrochemistry capabilities. One key factor plaguing the QCM in most sensor applications is the stability of the surface functionalisation. Diamond offers the most stable surface for functionalisation, the widest electrochemical window and the lowest noise floor. Unfortunately the growth of diamond on QCMs is problematic due to the low curie point of quartz, resulting in the loss of the piezoelectric properties of the QCM. In this work the replacement of the quartz with a high temperature stable piezoelectric material is proposed, and a nanocrystalline diamond coated sensor demonstrated.

4.
J Am Chem Soc ; 130(51): 17218-9, 2008 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-19049309

RESUMO

Boron doped diamond (BDD) thin film was found to exhibit higher photocurrent conversion efficiencies and photostability compared to commonly used transparent conducting oxides (ITO and FTO) owing to the matching energy levels and strong C-C bonding at the organic/diamond interface.

5.
Langmuir ; 24(14): 7269-77, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18558777

RESUMO

Label-free detection of DNA molecules on chemically vapor-deposited diamond surfaces is achieved with spectroscopic ellipsometry in the infrared and vacuum ultraviolet range. This nondestructive method has the potential to yield information on the average orientation of single as well as double-stranded DNA molecules, without restricting the strand length to the persistence length. The orientational analysis based on electronic excitations in combination with information from layer thicknesses provides a deeper understanding of biological layers on diamond. The pi-pi* transition dipole moments, corresponding to a transition at 4.74 eV, originate from the individual bases. They are in a plane perpendicular to the DNA backbone with an associated n-pi* transition at 4.47 eV. For 8-36 bases of single- and double-stranded DNA covalently attached to ultra-nanocrystalline diamond, the ratio between in- and out-of-plane components in the best fit simulations to the ellipsometric spectra yields an average tilt angle of the DNA backbone with respect to the surface plane ranging from 45 degrees to 52 degrees . We comment on the physical meaning of the calculated tilt angles. Additional information is gathered from atomic force microscopy, fluorescence imaging, and wetting experiments. The results reported here are of value in understanding and optimizing the performance of the electronic readout of a diamond-based label-free DNA hybridization sensor.


Assuntos
DNA/química , Diamante/química , Cristalização , DNA/ultraestrutura , Dessecação , Microscopia de Força Atômica , Conformação de Ácido Nucleico , Óptica e Fotônica , Espectrofotometria , Propriedades de Superfície
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