Search results for " Air"
showing 10 items of 703 documents
Energy performance improvements of a DEC system due to wet heat exchangers
2011
This work concerns an innovative desiccant and evaporative cooling (DEC) system for building air conditioning. The original system is an experimental DEC air handling unit installed at the Solar Laboratory of the University of Palermo and recently modified and updated. With the aim to increase the cooling effect due to water evaporation in the return air flow rate, the sensible heat exchanger was replaced with two cross flow flat plate heat exchangers installed in series, with continuous humidification of the secondary air flow. The new thermodynamic cycle is theoretically described and the realization of the real application is shown. Detailed operational data and energy performance indica…
Experimental results on adsorption beds for air dehumidification
2016
Desiccant rotors are commonly used in large scale solar cooling open cycle applications. As is well known, adsorption heat sensibly reduces the dehumidification capacity of the desiccant material and results in lower system performance. The aim of this work is to describe an innovative solution that permits simultaneous mass and heat transfer. In particular, two components working with silica gel fixed beds were studied and compared. The first component is a simple packed bed containing silica gel grains. The second component is a fin and tube heat exchanger commonly used in several air conditioning applications wherein the spaces between the fins are filled with silica gel grains. In this …
Life Cycle Assessment of a compact Desiccant Evaporative Cooling system: The case study of the “Freescoo”
2016
Abstract The paper aims at exploring the performances of a compact Desiccant Evaporative Cooling system called “Freescoo” (Free Solar Cooling) in comparison to standard conventional technologies. The Freescoo – that aims at applications in the residential sector and in small office buildings and includes a photovoltaic–thermal system – is analyzed, its monitored performance discussed and reported: under cooling conditions an Energy Efficiency Ratio of 12.8 is calculated, that reaches 50.7 if also photovoltaic generation is considered. To assess the performance of the proposed system a Life Cycle Assessment study was performed to investigate the system covering all its life, from the product…
ADVANCED SOLAR ASSISTED DESICCANT AND EVAPORATIVE COOLING SYSTEM EQUIPPED WITH WET HEAT EXCHANGERS
2011
Abstract This work concerns an innovative solar assisted desiccant and evaporative cooling (DEC) system for building air conditioning. In this system, air-to-air packaged wet heat exchangers are used to maximize the exploitation of the evaporative cooling potential associated with the exhaust air stream. The thermodynamic cycle is first theoretically described, and then an example of a real application is shown. The system presented is an experimental DEC system originally installed at the beginning of 2008 at the Solar Laboratory of the University of Palermo and recently modified and updated. These modifications have been implemented with the aim to foster some problems related to the conv…
Acetone measurements in the exhaled air by the cavity ring-down spectrometry
2020
Our work is focused to develop sensitive optical diagnostic methods for the detection of Volatile Organic Compounds in the breath. For the breath measurements, we have built a cavity ring-down spectrometer, operated in the UV region. The system was tested and calibrated using a KinTek automated permeation tube system with nitrogen as a carrier gas, as well as self- prepared acetone mixtures in air with known concentrations. In this paper, we present results of the measurements of acetone concentration in the breath for the test group of randomly selected 40 people in the age group over 50. We observed the values of acetone concentration in the breath in the range from 0,1 – 80 ppm, with a m…
RIGA International Airport development in Baltic Sea region aviation industry context
2021
In the paper the authors examined key Latvian economy indicators, specifically focusing on trends in development of aviation industry development. In particular, also attention was paid to passengers and cargo volume transportation dynamics, as well as to RIGA International Airport Development Plan through the year 2036. The authors compared operations of RIGA International Airport with available data from other leading Baltic Sea Region airports, specifically within 300 kilometres zone. Another requirement was, a competing airport had to be in the TOP 100 airports globally to be considered. KEY WORDS: RIGA International Airport, Baltic sea region, development plan. JEL CODES: M160, R110, R…
Digital signal processing for rail monitoring by means of ultrasonic guided waves
2007
Recent train accidents have reaffirmed the need for developing rail defect detection systems that are more effective than those used today. One of the recent developments in rail inspection is the use of ultrasonic guided waves (UGWs) and non-contact probing techniques to target transverse-type defects. Besides the obvious advantages of non-contact probing, that include robustness and a potential for large inspection speed, such a system can theoretically detect transverse defects under horizontal shelling or head checks. This paper demonstrates the effectiveness of digital signal processing to enhance the damage detection sensitivity of the non-contact system. The method proposed here comb…
Calcification is not the Achilles'heel of cold-water corals in an acidifying ocean
2015
Ocean acidification is thought to be a major threat to coral reefs: laboratory evidence and CO2 seep research has shown adverse effects on many coral species, although a few are resilient. There are concerns that cold-water corals are even more vulnerable as they live in areas where aragonite saturation (Omega ara) is lower than in the tropics and is falling rapidly due to CO2 emissions. Here, we provide laboratory evidence that net (gross calcification minus dissolution) and gross calcification rates of three common cold-water corals, Caryophyllia smithii, Dendrophyllia cornigera, and Desmophyllum dianthus, are not affected by pCO2 levels expected for 2100 (pCO2 1058 µatm, Omega ara 1.29),…
Emergence of Aspergillus fumigatus azole resistance in azole-naïve patients with chronic obstructive pulmonary disease and their homes.
2017
Azole-resistant Aspergillus fumigatus (ARAF) has been reported in patients with chronic obstructive pulmonary disease (COPD) but has not been specifically assessed so far. Here, we evaluated ARAF prevalence in azole-naïve COPD patients and their homes, and assessed whether CYP51A mutations were similar in clinical and environmental reservoirs. Sixty respiratory samples from 41 COPD patients with acute exacerbation and environmental samples from 36 of these patient's homes were prospectively collected. A. fumigatus was detected in respiratory samples from 11 of 41 patients (27%) and in 15 of 36 domiciles (42%). Cyp51A sequencing and selection on itraconazole medium of clinical (n = 68) and e…
Asthma Control: The Right Inhaler for the Right Patient
2015
Inhaled therapy is the cornerstone of asthma management in that it optimizes the delivery of the medication to the site of action. The effectiveness of inhaled therapy is affected by the correct choice of the device and proper inhalation technique. In fact, this influences the drug delivery and distribution along the bronchial tree, including the most peripheral airways. In this context, accumulating evidence supports the contribution of small airways in asthma, and these have become an important target of treatment. In reality, the “ideal inhaler” does not exist, and not all inhalers are the same. Advances in technology has highlighted these differences, and have led to the design of new d…