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101.
Current brief aims to introduce the concept of safety in European industrial sectors, particularly in mechanics and machinery industry. It also highlights the importance to ensure an even level of machinery safety along the European Union, setting up the appropriate frame and procedures to keep it under control. An overview over market surveillance activities for machinery (regulations, main actors and their roles) first at Community level, and secondly an approach to one of the Member States is also introduced.  相似文献   
102.
In this article, energy and exergy analyses are conducted for two integrated systems which can be used in HVAC applications. These two systems are analyzed for the cases of single generation, cogeneration and trigeneration, and their performances are evaluated through energy and exergy efficiencies. The parametric studies are performed to investigate the effects of using cogeneration and extended to trigeneration on the system performance. To perform the comparisons between the systems for multiple options, the same amounts of outputs (in terms of electricity, heating, cooling) are produced for all systems. The energy analyses of systems 1 and 2 show a great benefit for moving from single generation to trigeneration, with the trigeneration efficiencies of 83.5% and 87.2%, respectively, and single generation efficiencies of 47% for both systems. However, the exergy analyses show that trigeneration may not always become more efficient than single generation, particularly for system 1, due to the fact that the trigeneration exergy efficiency is 38.7% and the corresponding single generation efficiency is 44.3%. For system 2, the trigeneration exergy efficiency is 52.7% while the single generation efficiency becomes 44.3%. Depending on the type of cogeneration or cogeneration design, the system can be more efficient.  相似文献   
103.
Strongyloidiasis presents a major health hazard when reusing wastewater. Albendazol with a concentration of 4 mg/l, a contact time of 45 min, pH 1.2 and pH 10.2, killed the larva. The larva was also killed with a 0.03% concentration of iodine and a detention time of 30 min or a 0.04% concentration of iodine and a contact time of 10 min. The required detention time to inactivate larva in water was found to be 17 days. The minimum revealed residual chlorine to kill the larvae was 4 mg/l with 120 min of detention time, and a minimum contact time was found to be 80 min with a residual of 23 mg/l. Many methods are available to inactivate the Strongyloides stercoralis, which could be acids, alkaline chemicals, larvicidal chemicals, super chlorination, or just detention time. The best method must be determined according to the prevailing specific environmental site and the feasibility of the selected method(s).  相似文献   
104.
105.
In its role as a competitive producer of phosphate and potash Jordan has not suffered noticeably from the Resource Curse over the past 50 years. However, the effects on its economy because of its geographical proximity to major oil-producing states have been both positive and negative. It is arguable that an oil resource curse has applied to Jordan.  相似文献   
106.
The concentrations and chemical distributions of heavy metals (Cd, Cr, Ni, Zn, U, and V) in the Al-Jiza phosphate ores were investigated. Typically, the mean concentration values of Cd, Cr, Ni, U, and Zn are 15 ± 8, 109 ± 21, 34 ± 6, 211 ± 55, 142 ± 55, and 161 ± 57 mg kg?1, respectively. On the other hand, the encountered average concentration values of Cd, Cr, Ni, Zn, U, and V in the phosphate dust particles (<0.053) were found to be 22 ± 5, 179 ± 5, 67 ± 11, 441 ± 14, 225 ± 58, and 311 ± 9 mg kg?1, respectively. The contamination factors of U and Cr are greater than 1, indicating that these heavy metals could be potentially hazardous, if released to the environment. Multivariate statistical analysis allowed the identification of three main factors controlling the distribution of these heavy metals and the other chemical constituents. The extracted factors are as follows: francolite mineral factor, clay minerals factor, and diagenesis factor. Health risk assessments of non-cancerous effects in finer-grained size fraction that might be caused by contamination with the heavy elements have been calculated for both children and adults. The risk assessments in case of children for non-cancerous effects showed that U has values greater than the safe level of hazard index (HI = 1). In case of adults, the value of risk for U is also higher as compared to those of Cd, Ni, Cr, and Zn where it lies within the safe range of hazard index (HI < 1). Child health risk assessment indicates that children are more vulnerable to contaminants from phosphate mining than adults.  相似文献   
107.
Experiments were performed in a single cylinder common-rail diesel engine that adopts a low temperature premixed charge compression ignition (PCCI) mode. Combustion features of dimethyl carbonate (DMC)-diesel blends under various centers of heat release (COHRs) were revealed in details. With retarding of COHR, all the peaks of pressure and pressure rise rate and bulk gas temperature are postponed and declined in sequence. Normally, the crank angle of peak pressure is quite close to the COHR, while the peak of bulk gas temperature appears about 7°CA after COHR as a rule. The prolongation can be demonstrated at every stage of combustion such as q10 and q90 with the COHR being put backward. In addition, the heat release of diesel is completely slower than that of D10 fuel at various stages. Unfortunately, retarding of COHR implies a declining thermal efficiency of engines as well as a higher cyclic variation in general. Nevertheless, D10 blend has higher thermal efficiency than diesel thanks to high oxygen content of DMC and low boiling point that prompts better fuel atomization and complete combustion. Meanwhile, the cyclical variation of D10 is greater than diesel fuel owing to the low heat value, high latent heat of vaporization, and poor flammability of DMC. As a total, a comprehensive understanding of PCCI combustion features under different COHRs can be conducive to conducting effective management of combustion process and manipulating the subsequent emission performance to a favorable level.  相似文献   
108.
There are numerous small populated islands near western Sumatra in Indonesia. The Weh, Banyak, Mentawai, and Enggano islands are home to many Indonesians. These small islands have been found to be effective at reducing tsunami wave energy on several occasions. At the same time, they are situated around Sumatras active subduction zone and are often among the areas most affected by tsunamisas in the case of Pulo Raya Island, in the western Aceh Jaya district about 800 m from Sumatra. Pulo Raya was devastated by the 2004 Indian Ocean tsunami. This study investigates the hydrodynamic processes of reflected tsunami waves and their impact on Pulo Raya, using a Cornell Multi-grid COupled Tsunami (COMCOT) model to simulate the tsunami wave runup and subsequent hydrodynamic processes. The simulation confirms eyewitness accounts that it was not the initial runup, but the reflected waves that devastated the worst-hit areas of the island. As a result, we can recommend that governments and communities on small islands need to anticipate the impacts of reflected waves following a tsunami, especially at lee side of of the island that was perceived to be a safer place by the island community before the 2004 Indian Ocean tsunami.  相似文献   
109.
Gillnet fisheries are widely thought to pose a conservation threat to many populations of marine mammals, seabirds, and turtles. Gillnet fisheries also support a significant proportion of small‐scale fishing communities worldwide. Despite a large number of studies on protected‐species bycatch in recent decades, relatively few have examined the underlying causes of bycatch and fewer still have considered the issue from a multitaxon perspective. We used 3 bibliographic databases and one search engine to identify studies by year of publication and taxon. The majority of studies on the mechanisms of gillnet bycatch are not accessible through the mainstream published literature. Many are reported in technical papers, government reports, and university theses. We reviewed over 600 published and unpublished studies of bycatch in which causal or correlative factors were considered and identified therein 28 environmental, operational, technical, and behavioral factors that may be associated with high or low bycatch rates of the taxa. Of the factors considered, 11 were associated with potential bycatch reduction in 2 out of the 3 taxa, and 3 factors (water depth, mesh size, and net height) were associated with trends in bycatch rate for all 3 taxa. These findings provide a basis to guide further experimental work to test hypotheses about which factors most influence bycatch rates and to explore ways of managing fishing activities and improving gear design to minimize the incidental capture of species of conservation concern while ensuring the viability of the fisheries concerned.  相似文献   
110.
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