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Abstract

Thermo-optic properties enhancement of the bi-stable temperature threshold sensors based on a partially filled photonic crystal fiber was reported. Previously tested transducers filled with a selected group of pure n-alkanes had in most cases differences between switching ON and OFF states. Therefore, the modification of filling material by using additional crystallization centers in the form of gold nanoparticles was applied to minimize this undesirable effect. The evaluation of the thermodynamic properties of pentadecane and its mixtures with 14 nm spherical Au nanoparticles based on the differential scanning calorimetry measurements was presented. Optical properties analysis of sensors prepared with these mixtures has shown that they are bounded with refractive index changes of the filling material. Particular sensor switches ON before melting process begins and switches OFF before crystallization starts. Admixing next group of n-alkanes with these nanoparticles allows to design six sensors transducers which change ON and OFF states at the same temperature. Thus, the transducers with a wider temperature range for fiber-optic multi-threshold temperature sensor tests will be used.

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Authors and Affiliations

N. Przybysz
P. Marć
E. Tomaszewska
J. Grobelny
L.R. Jaroszewicz
ORCID: ORCID
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Abstract

A field survey has been conducted for the study area using the Global Positioning System (GPS) and geological and geomorphological maps of the area. The study area is one of the important areas in Iraq characterized by scarce water resources. The purpose of the study is to determine the hydro-chemical processes and their relationship to groundwater quality carried out in the southwestern desert region of Iraq, where the region lacks extensive studies of water resources. Twenty-eight groundwater samples were collected from wells distributed between the eastern borders of Saudi Arabia and the West Bank of the Euphrates River. For the purpose of hydrogeochemical analyses, the Fetter method was used to collect and examine samples. A large part of the recharge area is located in Saudi Arabia, where the groundwater bearing aquifer represented by the Dammam formation extends to Iraq and Saudi Arabian International borders. The analysis determined the order of cations (Na+ > Ca2+ > Mg2+ > K+) and anions (Cl– > SO42– > HCO3–). High values of the variation coefficient (CV) correspond to the concentration of potassium, sodium and chloride ions (CV: 68.7, 64.7 and 64 respectively). To identify the hydrochemical water facies, the Piper diagram was used. It was found that 53% of the water samples belong to the Na-Cl type and 40% are of the Ca-Mg-Cl type, while the rest of the samples are the Ca-Cl type. To identify geochemical processes, it was found that ion exchange processes via chloroalkaline indices 1 and 2 are prevalent between Ca2+, Mg2+ in the groundwater and Na+, K+ in water bearing rocks. To learn more about the processes that led to the concentration of certain ions, such as sodium, it was found that they tend to be of silicate minerals related to surface runoff of water in recharge areas and carbonic rocks. It was also found that rock / soil-groundwater interaction and evaporation processes were the formal processes in the saturated zone and evaporation in the unsaturated zone are prevalent processes of groundwater ion concentration.
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Authors and Affiliations

Kareem Ghafel Al-Mutawqi
1
ORCID: ORCID
Salam Hussein Ewaid
2
ORCID: ORCID
Salwan Ali Abed
1
ORCID: ORCID
Nadhir Al-Ansari
3
ORCID: ORCID
Mudhafar A. Salim
4
ORCID: ORCID
Ameer J. Kadhim
5
ORCID: ORCID

  1. University of Al-Qadisiyah, College of Science, Iraq
  2. Technical Institute of Shatra, Southern Technical University, Basra, Iraq
  3. Luleå University of Technology, Laboratorievägen 14, 971 87 Luleå, Sweden
  4. Arab Regional Center for World Heritage, Manama, Bahrain
  5. Ministry of Water Resources, General Commission of Groundwater, Baghdad, Iraq
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Abstract

Access to clean and sufficient drinking water is difficult in much of Ethiopia’s Afar Region. It is observed that many schemes in the region are non-functional. The study was conducted to overcome the observed problem in seven selected districts of the region. The study regarded hand-dug wells and roof water collection systems, which are the two most common features in the research areas. Eight hand-dug wells and sixteen roof water harvestings are purposively included in the study. All the water points are constructed by Kelem Ethiopia which is a non-governmental organisation and the foremost local organisation for the communities. As per the research survey, the average functional status of the hand-dug well schemes is 65.75% and the roof water harvesting schemes is 22.94%. The research was based on the qualitative data collected on site. The hand-dug well sites were evaluated using 10 parameters, and the roof water harvesting schemes were analysed using 12 parameters. The main non-functional aspects of the scheme are lack of community ownership, drying up of water sources, lack of maintenance and rehabilitation, poor coordination of beneficiaries and school roofs blowing off. Most schemes still require minor to major maintenance and rehabilitation. According to the research, the solutions for water supply are identified in relation to the desired objective.
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Authors and Affiliations

Melese C. Shumie
1

  1. Debre Berhan University, Department of Civil Engineering, Debre Berhan, PO Box 445, Ethiopia

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