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121.
The condenser is a piece of equipment used to effectively transfer heat from water to the environment. The fin and tube condenser is the most commonly used in commercial applications. The improved performance of heat transfer in the fin and tube condenser is a significant area of study all over the world because optimizing the efficiency of heat transfer in the condenser will contribute to enhancing the effectiveness of system performance. The vapor deposition, plasma spray, and thermal spray techniques are being used, and it is determined that a heat transfer enhancing coating improves condenser performance. This review discusses the nanomaterial coating over the fin and tube condenser in detail. The various nanomaterial coatings with various propositions and coating methods had been discussed with the evidence of previous researchers. At a 50-degree inclination angle on the condensate plate, the condensate over the coating surface increases by more than 30%. The thermal properties of the working fluid are improved over the condenser, and the overall effectiveness of the condenser is increased by approximately 40% over the non-coated condenser. A 1% volumetric concentration of Nanoparticles in the coated material achieves a maximum efficiency increase of 78.7%.  相似文献   
122.
Oral administration of arsenic trioxide(3 and 6 mg/kg body weight/d) for 30 d caused, as compared with vehicle control, dose-dependent significant reductions in body weight, absolute weight, protein, glycogen, as well as, total, dehydro and reduced ascorbic acid contents both in the liver and kidney of arsenic-treated mice. Succinic dehydrogenase(SDH) and phosphorylase only in the liver activities were significantly reduced in a dose-dependent manner. Acid phosphatase activity was significantly decreased in the liver of low dose arsenic-treated animals;however, significant rise in its activity was observed in high dose group. As compared with vehicle control, treatment also caused significant dose-dependent reductions in SDH, alkaline phosphatase and acid phosphatase activities in the kidney of mice. Vitamin E cotreatment as well as, 30 d withdrawal of arsenic trioxide treatment with or without vitamin E caused significant amelioration in arsenic-induced toxicity in mice. Administration of vitamin E during withdrawal of treatment also caused significant amelioration as compared from only withdrawal of the treatment. It is concluded that vitamin E ameliorates arsenic-induced toxicities in the liver and kidney of mice.  相似文献   
123.
It is well known that dilute sulfuric acid pretreatment of the lignicellulosisc biomass is an effective approach used for the production of the ethanol. However, there are less studies on the biogas production from the pretreated lignocellulosics and hardly data available on the codigestion of cattle manure with the pretreated lignocellulosisc material. The aim of this study was to evaluate biomethane production potential of codigestion of cattle manure with dilute acid pretreated lignocellulosic biomass. Sugarcane bagasse and rice husk was pretreated with dilute sulfuric acid or phosphoric acid at 121°C for 20 minutes and subsequently subjected to anaerobic digestion alone or codigested with cattle manure.

The results showed that codigestion of 1% phosphoric acid pretreated rice husk with cattle manure led to the highest methane production of 115 Nmlg?1VS while monodigestion of cattle manure and phosphoric acid pretreated rice husk produced 98 and 87 Nmlg?1VS, respectively. An inhibition was observed in anaerobic digestion of sulfuric acid pretreated rice husk and sugarcane bagasse during monodigestion and codigestion with cattle manure.

The study concludes that dilute phosphoric acid pretreated lignocellulosics like sugarcane bagasse and rice husk can be used as a cosubstrate with cattle manure in anaerobic digestion for enhanced methane production. Dilute sulfuric acid pretreatment, which is effective method for the bioethanol production, causes inhibition during anaerobic digestion of the pretreated lignocellulosics.  相似文献   
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This research deals with the sulfurous spring waters flow along the course of the Euphrates River in western Iraq in the area extended between Haqlaniya and Hit within the Al-Anbar governorate. Eleven springs (3 in Haqlanya, 4 in Kubaysa and 4 in Hit) have been addressed for the purpose of water evaluation for balneology, drinking, irrigation and aquaculture (fish farming). In order to meet the objectives of this research, all springs were sampled and analyzed for the total dissolved solid, electrical conductivity, pH, temperature, major cations (Ca2+, Mg2+, Na+ and K+), major anions (SO4 2?, Cl?, HCO3 ? and CO3 2?), minor anions (PO4 3?and NO3 ?) as well as the trace elements that included Pb, Zn, Cd, Ni, Fe, Mn, Cu, Br, F, Ba, B, Sr, Al, As, Cr, Hg and Se. The International Standards of World Health Organization are used for assessing the water quality. The results revealed that the springs belong to the tepid springs of 27–30 °C and classified as hypothermal to the thermal springs. Lithochemistry and geochemical processes clearly affected the water chemistry. The hydrogeochemical processes are responsible for the element enrichment in water by the chemical dissolution of carbonate and gypsum and evaporation as well. The results of the study indicate the possibility of using spring water for therapeutic purposes, but not allowed for drinking and aquaculture (fish farming), except those free of H2S gas. On the other hand, it can be used for irrigation with risk. However, soil type as well as proper selection of plants should be taken into consideration.  相似文献   
127.
Environmental Science and Pollution Research - Energy is an essential parameter for the economic growth and sustainable development of any country. Due to the rapid increase in energy demand,...  相似文献   
128.
In Malaysia, various efforts have been introduced to increase the knowledge, skills and awareness of citizens to the benefit of the environment by means of a variety of programmes. However, uncertainty about the effectiveness of environmental education programmes and the way they contribute to sustainability still exists. This paper reports on an evaluation of the Kelab Pencinta Alam (KPA) (School Nature Clubs) programme organised by the Malaysia Nature Society and the Forest Research Institute of Malaysia. The Kellogg Logic Model was used as an evaluative instrument as the impact of the programme had to be determined. This was done through questionnaires to teachers and principals in KPA schools. School visits were also undertaken to evaluate workplace success and to validate the findings from the questionnaires. Overall, the evaluation showed a high level of success for the programme.  相似文献   
129.
The tropical rainforest of Malaysia holds one of the richest flora in the world. The favourable climate has produced flora of amazing richness and variety. Terrestrial vegetation of tropical rainforests is an important feature of the environment. Plants play a major role in the environment and conservation of a particular environment depends fundamentally on the maintenance of existing plants and their communities and hierarchies. Interference in the balance of the ecosystem may produce radical changes that lead to progressive deviations from the original situation. Therefore, the application of a computer technology in the form of an expert system (ES) will be able to help in the analysis and management of the EIA information. The ES is named VEGEVIC. Application of the system will lead to greater consistency in the application of EIA through implementation of a standard approach.  相似文献   
130.
This study was conducted to investigate the effectiveness of a continuous free surface flow wetland for removal of heavy metals from industrial wastewater, in Gadoon Amazai Industrial Estate (GAIE), Swabi, Pakistan. Industrial wastewater samples were collected from the in-let, out-let and all cells of the constructed wetland (CW) and analyzed for heavy metals such as lead (Pb), cadmium (Cd), iron (Fe), nickel (Ni), chromium (Cr) and copper (Cu) using standard methods. Similarly, samples of aquatic macrophytes and sediments were also analyzed for selected heavy metals. Results indicate that the removal efficiencies of the CW for Pb, Cd, Fe, Ni, Cr, and Cu were 50%, 91.9%, 74.1%, 40.9%, 89%, and 48.3%, respectively. Furthermore, the performance of the CW was efficient enough to remove the heavy metals, particularly Cd, Fe, and Cu, from the industrial wastewater fed to it. However, it is suggested that the metal removal efficiency of the CW can be further enhanced by using proper management of vegetation and area expansion of the present CW.  相似文献   
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