Search results for "Env"

Parametric Models for Predicting the Performance of Wind Turbines

2020

Abstract Performances of eight parametric power curve models for wind turbines, which can be used for the planning and management of wind energy projects, are compared in this study. Initially, the manufacturer’s power curves of four wind turbines are compared with their field performances. Then, the parametric models are developed for these turbines which are tested with their site performances. Out of the models, WERA showed the best performance in case of all the turbines. Finally, a method for using WERA in extrapolating the performance of turbines with limited test data is demonstrated with the case of a 1 kW turbine.

Experimental investigation of the effect of moisture on the acoustic properties of lightweight substrates used in green envelopes

2021

International audience; Substrates are used in green walls and roofs to supply air and water to the roots of the growing plants. These substrates are porous with micropores which store water and macropores which facilitate drainage and air entry. Effect of moisture on acoustic absorption is studied for two lightweight substrates: coir dust and perlite. Measurement of dry and moistened substrates are conducted to evaluate their effective speed of sound, attenuation, characteristic impedance, compressibility and density between 100 Hz and 1000 Hz using an impedance tube and the three microphone-two load method. Effect of moisture on these quantities is found to depend strongly upon the intera…

Review of the PEA Method for Space Charge Measurements on HVDC Cables and Mini-Cables

2019

This review takes into account articles and standards published in recent years concerning the application of the Pulsed Electro Acoustic (PEA) method for space charge measurement on High Voltage Direct Current (HVDC) cables and mini-cables. Since the 80s, the PEA method has been implemented for space charge measurements on flat specimens in order to investigate space charge phenomena and to evaluate the ageing of dielectrics. In recent years, this technique has been adapted to cylindrical geometry. Several studies and experiments have been carried out on the use of the PEA method for full size cables and HVDC cable models. The experiments have been conducted using different arrangements of…

High-Resolution Stimulated Raman Spectroscopy and Analysis of the ν1 Stretching Band of GeD4

2007

The high-resolution stimulated Raman spectrum of the ν1 band of GeD4 with natural isotopic abundance germanium has been recorded. It has been analyzed as part of the ν1/ν3 stretching dyad. The ν1 and ν3 band centers have been deduced for all the isotopologues. Copyright © 2006 John Wiley & Sons, Ltd.

Introduction to the special issue on molecular spectroscopy, atmospheric composition and climate change

2018

International audience

Antineutrino monitoring of spent nuclear fuel

2016

Military and civilian applications of nuclear energy have left a significant amount of spent nuclear fuel over the past 70 years. Currently, in many countries world wide, the use of nuclear energy is on the rise. Therefore, the management of highly radioactive nuclear waste is a pressing issue. In this letter, we explore antineutrino detectors as a tool for monitoring and safeguarding nuclear waste material. We compute the flux and spectrum of antineutrinos emitted by spent nuclear fuel elements as a function of time, and we illustrate the usefulness of antineutrino detectors in several benchmark scenarios. In particular, we demonstrate how a measurement of the antineutrino flux can help to…

Models for supercontinuum generation beyond the slowly-varying-envelope approximation

2014

International audience; We show numerically that both the modified Korteweg–de Vries and the sine-Gordon models are conducive to the generation of supercontinua with spectral bandwidths of several octaves, when an intense short pulse is launched as the initial condition. These models beyond the slowly-varying-envelope approximation could play an important role in modeling supercontinuum generation in gas-filled hollow waveguides.

The Challenges of Air Protection and Control

2016

A New LA ‐ ICP ‐ MS Method for Ti in Quartz: Implications and Application to High Pressure Rutile‐Quartz Veins from the Czech Erzgebirge

2016

Experimental determination of the pressure and temperature controls on Ti solubility in quartz provides a calibration of the Ti-in-quartz (TitaniQ) geothermometer applicable to geological conditions up to ~ 20 kbar. We present a new method for determining 48Ti mass fractions in quartz by LA-ICP-MS at the 1 μg g−1 level, relevant to quartz in HP-LT terranes. We suggest that natural quartz such as the low-CL rims of the Bishop Tuff quartz (determined by EPMA; 41 ± 2 μg g−1 Ti, 2s) is more suitable than NIST reference glasses as a reference material for low Ti mass fractions because matrix effects are limited, Ca isobaric interferences are avoided, and polyatomic interferences at mass 48 are i…

Immunostimulatory Potential of Natural Compounds and Extracts: A Review

2020

The proper functioning of human immune system is essential for organism survival against infectious, toxic and oncogenic agents. The present study aimed to describe the scientific evidence regarding the immunomodulatory properties of the main micronutrients and specific phytochemicals. Plants of food interest have the ability to dynamically affect the immune system through particular molecules. Plant species, type of compounds and biological effects were herein reviewed mainly focusing on plants which are not commonly used in food supplements. Several efficient phytoproducts showed significant advantages compared to synthetic immunomodulators, being good candidates for the development of i…