Search results for "flow [Keywords]"
showing 10 items of 469 documents
Impact analysis of MPL and PEM thickness on temperature distribution within PEFC operating at relatively higher temperature
2020
Abstract In Japan, it is recommended to operate Polymer Electrolyte Fuel Cell (PEFC) at temperature around 90 °C for stationary applications during the period from 2020 to 2025. However, the present PEFC is using Nafion polymer electrolyte membrane (PEM) and operated within the temperature range from 60 °C to 80 °C. It is important to understand the temperature distribution in a cell of PEFC for improving the performance and to realize the long life span. This study focuses on use of micro porous layer (MPL), which can promote the moisture transfer in order to control the temperature distribution. The aim of this study is to analyze the impact of MPL on temperature distribution at reaction …
Bronchial thermoplasty in severe asthma: food for thoughts
2014
Asthma is a complex inflammatory disorder of the airways characterized by airway hyper-responsiveness and variable, reversible, airflow obstruction. Bronchial thermoplasty (BT) is a new modality for treating asthma. It targets airway smooth muscles (ASM) by delivering a controlled specific amount of thermal energy (radiofrequency ablation) to the airway wall through a dedicated catheter. The use of bronchial thermoplasty has been widely discussed for its potential in the treatment of asthma, since it seems to be able to reduce the symptoms of asthma. The definitive study for BT (AIR2 trial) employed a randomized, double-blind, sham-controlled design and enrolled 288 subjects with severe per…
Decomposition studies of group 6 hexacarbonyl complexes. Part 1: Production and decomposition of Mo(CO)6 and W(CO)6
2015
Abstract Chemical studies of superheavy elements require fast and efficient techniques, due to short half-lives and low production rates of the investigated nuclides. Here, we advocate for using a tubular flow reactor for assessing the thermal stability of the Sg carbonyl complex – Sg(CO)6. The experimental setup was tested with Mo and W carbonyl complexes, as their properties are established and supported by theoretical predictions. The suggested approach proved to be effective in discriminating between the thermal stabilities of Mo(CO)6 and W(CO)6. Therefore, an experimental verification of the predicted Sg–CO bond dissociation energy seems to be feasible by applying this technique. By in…
Evaluation of two oxygen analyzers by computerized data acquisition and processing
1986
Monitoring of inspired oxygen concentration during anesthesia with nitrous oxide is becoming accepted as essential. This type of monitoring demands accurate monitors that respond rapidly. We evaluated two such devices for their response patterns to rapid changes in oxygen concentration, a galvanic or "fuel cell" unit and a polarographic device. Data were stored after analog-to-digital conversion. The response patterns to stepwise changes in nitrous oxide and oxygen mixtures were recorded at flow rates ranging from 2 to 10 L/min. Both units responded accurately to all changes in the absolute oxygen concentration; the polarographic unit was, on average, twice as fast. Responsiveness to nitrou…
Setting the Stage: How to Perform Intracoronary Pressure Measurements
2016
FFR has become an established technology, and alternative approaches, like the instantaneous flow reserve (iFR), are currently being validated. FFR and iFR are generally easy to perform and interpret, but, as with all other technologies, oversimplification also carries risks. In the first chapter of this book, we present the basics of FFR measurements, including basic tips and tricks, and a short introduction to the devices available on the market.
Advanced techniques for solving groundwater and surface water problems in the context of inverse methods and climate change.
2021
[ES] El tema de la investigación se centra en técnicas avanzadas para manejar problemas de aguas subterráneas y superficiales relacionados con métodos inversos y cambio climático. Los filtros de Kalman, con especial atención en Ensemble Smoother with Multiple Data Assimilation (ES-MDA), se analizan y mejoran para la solución de diferentes tipos de problemas inversos. En particular, la principal novedad es la aplicación de estos métodos para la identificación de series temporales. La primera parte de la tesis, luego de la descripción del método, presenta el desarrollo de un software escrito en Python para la aplicación de la metodología propuesta. El software cuenta con un flujo de trabajo f…
Constructed Wetlands as Sustainable Technology for the Treatment and Reuse of the First-Flush Stormwater in Agriculture—A Case Study in Sicily (Italy)
2020
This paper describes a case study that was carried out on a Sicilian company (Italy) dealing with separate waste collection and recycling of glass. The aims of this study were to evaluate the overall efficiency of a vertical subsurface flow system (VSSFs) constructed wetland (CW) operating for the treatment of first-flush stormwater and the effects of treated wastewater on the morphological and aesthetic characteristics of ornamental pepper and rosemary plants. The system had a total surface area of 46.80 m2 and was planted with common reed and giant reed. Wastewater samples were taken from October 2018 to July 2019 at the CW inlet and outlet for chemical-physical and microbiological charac…
Theoretical prediction of rainfall intensity for a small rainfall simulator
2022
In this contribution, a theoretical approach was developed for predicting rainfall intensity for a small rainfall simulator. The developed equation was tested for two different devices and different pressure head and water temperature values. The proposed relationship was found to have a good predictive ability of rainfall intensity. The proposed theoretical approach could be usable with other devices that operate on the same principles of the simulator considered in this investigation.
Improving transferability strategies for debris flow susceptibility assessment: Application to the Saponara and Itala catchments (Messina, Italy)
2017
Abstract Debris flows can be described as rapid gravity-induced mass movements controlled by topography that are usually triggered as a consequence of storm rainfalls. One of the problems when dealing with debris flow recognition is that the eroded surface is usually very shallow and it can be masked by vegetation or fast weathering as early as one-two years after a landslide has occurred. For this reason, even areas that are highly susceptible to debris flow might suffer of a lack of reliable landslide inventories. However, these inventories are necessary for susceptibility assessment. Model transferability, which is based on calibrating a susceptibility model in a training area in order t…
The measurement of light transmission through an irradiated fluidised bed
1983
Abstract The transmission of light through an irradiated fluidised bed with vertical flat walls containing catalytic particles has been experimentally studied. The amount of light transmitted through the reactor was measured at different levels by a photocell. The experimental variables studied included: (i) gas flow rate, varying from 2 to more than 10 times that required for minimum fluidisation; (ii) mean particle size, ranging from 0.138 to 0.275 mm; and (iii) internal bed thickness from 2.1 to 4.9 mm. The effect of the reflectance of the particles was also examined. Results show that the amount of light transmitted through a flat fluidised bed is low. The average transmitted light has …