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1.
Abstract The main brackish groundwater resources in the State of Kuwait are the groundwater located in the Kuwait Group and the Dammam limestone aquifers. Most of the groundwater used in the State of Kuwait is for irrigation, some part of it is used for domestic purposes and for small scale industries. Since rainfall is seasonal and is less than the annual evaporation, the recharge from rainfall is negligible. Water levels in both the aquifers are highly affected by the pumping rate from each well. The groundwater is extracted heavily resulting in decline of water levels and the deterioration of groundwater quality though there is underflow from Saudi Arabia. Improvement of the groundwater management is essential for maintaining long-term productivity of the aquifers in the State of Kuwait. 相似文献
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Abdel Monem Mohamed Soltan Hassan Elshimy Fawzia Abd EL-Raoof Florian Fuchs Andreas Köenig Ahmed Mohamed Yahya Mohamed Mostafa AbdelFattah Mohamed Serry Herbert Pöllmann 《Ceramics International》2018,44(6):5855-5866
The aim of this work is to study the effect of phase composition and microstructure of cordierite-based co-clinkers on the electrical properties and coefficient of thermal expansion of cordierite briquettes. To achieve this aim talc and kaolinite samples were collected from quarries in the Egyptian desert. The samples are characterized using XRD, XRF, polarized light, cathodoluminescence and SEM microscopy attached with EDAX, in addition to X-ray micro-computed tomography (3D- µXCT). The electrical properties and coefficient of thermal expansion of the cordierite briquettes are determined using HiTESTER instrument and automatic Netzsch DIL402 PC dilatometer, respectively.Five talc-based batches were shaped and fired in the temperature range 1000–1350 °C for 2 h. The microstructural and physical characteristics of the resulted cordierite-based co-clinkers depend mainly on the viscosity of the liquid phase developed during firing. The microchemistry of the cordierite briquettes confirms their enrichment of both cordierite and ferroan-cordierite crystallized directly from locally developed melts. The dielectric constant and loss factor values for cordierite briquettes allow their possible use as insulator components in electronic applications. 相似文献
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Salsabeel Al-Sodies Nadjet Rezki Fawzia Faleh Albelwi Mouslim Messali Mohamed R. Aouad Sanaa K. Bardaweel Mohamed Hagar 《International journal of molecular sciences》2021,22(19)
Novel dicationic pyridinium ionic liquids tethering amphiphilic long alkyl side chains and fluorinated counter anions have been successfully synthesized by means of the quaternization of the dipyridinium hydrazone through its alkylation with different alkyl halides. The resulting halogenated di-ionic liquids underwent a metathesis reaction in order to incorporate some fluorinated counter anions in their structures. The structures of all the resulting di-ionic liquids were characterized by several spectroscopic experiments. The antitumorigenic activities of the investigated compounds were further studied against three different human lung cancer cell lines. Compared to the standard chemotherapeutic agent, cisplatin, the synthesized di-ionic liquids exerted equal, even more active, moderate, or weak anticancer activities against the various lung cancer cell lines under investigation. The observed anticancer activity appears to be enhanced by increasing the length of the aliphatic side chains. Moreover, dicationic pyridinium bearing a nine carbon chain as counter cation and hexafluoro phosphate and/or tetrafluoro bororate as counter anion were selected for further evaluation and demonstrated effective and significant antimetastatic effects and suppressed the colonization ability of the lung cancer cells, suggesting a therapeutic potential for the synthesized compounds in lung cancer treatment. 相似文献
5.
F. Al-Ruwaih 《Bulletin of Engineering Geology and the Environment》2001,60(4):301-314
The field pH and contents of basic cations, anions, total alkalinity and other aqueous species have been measured in 89 groundwater
samples collected from clastic sediments and carbonate aquifers of Kuwait. The mean molar ratio of Mg2+/Ca2+ is 0.63 and 0.48 for the carbonate and clastic aquifers respectively, indicating that the groundwater of the carbonate aquifer
is in equilibrium with calcite and dolomite, the calculated mean PCO2 of the clastic and carbonate aquifers suggesting a deep closed environment system. The clastic aquifer is supersaturated
with respect to calcite, aragonite, quartz and chalcedony, undersaturated to near-saturated with dolomite and undersaturated
with respect to gypsum, anhydrite and halite, whereas the carbonate aquifer is supersaturated with respect to dolomite, calcite,
aragonite and quartz but undersaturated with anhydrite, gypsum and halite. The salinity of both aquifers increases in the
direction of flow. The water types are dominantly NaCl and Na2SO4 in the clastic aquifer and Na2SO4, CaSO4 and NaCl in the carbonate aquifer.
Electronic Publication 相似文献
6.
Fawzia Bardag-Gorce Alissa Diaz Robert Niihara Jeremy Stark Daileen Cortez Alexander Lee Richard Hoft Yutaka Niihara 《International journal of molecular sciences》2022,23(7)
Purpose: The purpose of the present study is to investigate the expression of aldehyde dehydrogenases (ALDHs) in rabbit corneas with limbal stem cell deficiency (LSCD) and corneas treated with cultured autologous oral mucosa epithelial cell sheet CAOMECS designed to reconstruct the ocular surface with LSCD. Methods: New Zealand white rabbit autologous oral mucosal epithelial cells were isolated from a buccal biopsy and cultured to be grafted back onto corneas of rabbit model of LSCD. Immunofluorescent staining and Western blot analysis were used to compare the expression of ALDH1A1 and ALDH1A3 in healthy, LSCD-diseased, CAOMECS treated corneas. Human oral mucosal and corneal epithelial cells (OMECS and CECs) were cultured and treated with retinoic acid (RA) to further investigate the expression of ALDHs. Results: In healthy corneas, ALDH1A1 and ALDH1A3 were markedly expressed in basal cells of corneal epithelium. In LSCD diseased corneas, ALDH1A1 and ALDH1A3 were markedly expressed in the conjunctivalized apical epithelial cells, the goblet cells, and the stroma. CAOMECS grafted corneas showed a decreased expression of ALDHs as compared to LSCD diseased corneas. Western blot analysis confirmed the up regulation of ALDH1A1 and ALDH1A3 expression in LSCD-diseased corneal epithelial cells. CAOMECS expressed low levels of ALDH1A1 and ALDH1A3, as compared to diseased CECs (D-CEC). When ALDH1A3 was up regulated by retinoic acid treatment in OMECS, Pax-6 expression was down regulated, suggesting a decrease in regenerative capacity when ALDH enzymes are up regulated. Conclusions: These findings report for the first time the up regulation of ALDH1A1 and ALDH1A3 in rabbit corneas with LSCD and document that CAOMECS grafting used to reconstruct corneal epithelium may reduce the expression levels of ALDH enzymes. 相似文献
7.
F. M. Al-Ruwaih H. A. Qabazard 《Bulletin of Engineering Geology and the Environment》2005,64(2):175-191
Al-Atraf is one of the water well fields of Kuwait supplying Kuwait City with the brackish groundwater obtained from the Kuwait Group aquifer of Miocene–Pleistocene age. The study determined the hydrogeological and hydrochemical characteristics of the groundwater in order to identify the major chemical processes that influence the groundwater quality of the study area. The results of the aquifer test analyses indicate that the Kuwait Group is a confined to semi-confined aquifer, with a transmissivity ranging between 62 and 321 m2/day. The flow net analysis implied that the groundwater moves from southwest to northeast. The estimated transmissivity values agree well with those calculated from the aquifer test. The results of the chemical analyses data of the Al-Atraf field show that the groundwater is mainly brackish, of NaCl and Na2SO4 water types. The groundwater is undersaturated with respect to halite, gypsum and anhydrite and supersaturated with respect to quartz, dolomite and calcite in the direction of groundwater flow. The average Pco2 of the groundwater is higher than the Pco2 of the earths atmosphere indicating that the groundwater is supplied with CO2 during the infiltration processes and dissolves the carbonate minerals under closed-system conditions. 相似文献
8.
The Kuwait Group aquifer is a major source of brackish groundwater in the State of Kuwait. The aquifer ranges in thickness
from 150–400 m. In the Umm Gudair well field, the water has total dissolved solids ranging from 3,130 to 4,790 mg/l. According
to the Sulin classification, all the Kuwait Group aquifer samples are characterized as Cl–Mg or Cl–Ca genetic water types.
The chemical data indicate that the aquifer is generally in equilibrium with respect to calcite, dolomite and gypsum but undersaturated
with respect to halite and polygorskite. The study has indicated that de-dolomitization is the major geochemical process controlling
the chemistry of this aquifer, increasing the major complexes of sulphate and carbonate due to the dissolution of gypsum.
The ratio of Cl/Na indicates that the Na+ ions have been taken from the Kuwait Group aquifer by reverse ion exchange.
相似文献
9.
F. M. Al-Ruwaih S. A. Ben-Essa 《Bulletin of Engineering Geology and the Environment》2004,63(1):57-70
The study area, Al-Shagaya Field-F, is located at the south western part of Kuwait and includes twenty-seven production water wells, tapping the Kuwait Group aquifer. The main objectives of this study were to identify the aquifer type, determine its properties, outline the geological factors and the hydrochemical processes that control the quality of the groundwater of the study area, and to assess the water quality of the Kuwait Group aquifer. Analyses of aquifer test data revealed that the Kuwait Group aquifer acts as a semi-confined to confined aquifer, with a range of transmissivity values between 103 and 1,198 m2/day. The initial water level ranges from 70 to 146 m (M.S.L). The estimated quantity of groundwater entering the study area is about 12,950 m3/day. The chemical analyses show that the groundwater of the study area is a brackish water type, with total dissolved solids ranging from 3,586 to 5,334 mg/l. The aquifer salinity increases in the direction of regional flow towards the NE. The average pH value is 7.7 and the average electrical conductivity is 5,349 s/cm. Groundwater is highly concentrated with Na+, Ca2+, Cl- and SO42- and is depleted in HCO3- and Mg2+ ions. It is characterized by secondary salinity, where the alkaline earths exceed the alkalies and strong acids exceed weak acids. Three groundwater chemical types are recognized: NaCl, Na2SO4 and CaCl2. The NaCl water type is the most abundant in the study area. The main genetic types of water are: MgCl2 and Na2SO4. It is found that the groundwater is oversaturated with respect to aragonite and calcite and undersaturated with respect to anhydrite, gypsum, halite and dolomite. A comparison of the hydrochemical coefficients of Na+/Cl-, SO42-/Cl- and Ca2+/Mg2+ in the study area with those of seawater and river water shows that the groundwater of the study area is a mixture of marine and continental water. 相似文献
10.
Strengthening of steel structures using externally-bonded carbon fibre reinforced polymers ‘CFRP’ is a rapidly developing technique. This paper describes the behaviour of axially loaded flat steel plates strengthened using carbon fibre reinforced polymer sheets. Two steel plates were joined together with adhesive and followed by the application of carbon fibre sheet double strap joint with different bond lengths. The behaviour of the specimens was further investigated by using nonlinear finite element analysis to predict the failure modes and load capacity. In this study, bond failure is the dominant failure mode for normal modulus (240 GPa) CFRP bonding which closely matched the results of finite elements. The predicted ultimate loads from the FE analysis are found to be in good agreement with experimental values. 相似文献