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121.
In order to achieve sustainable development in agriculture, it is necessary to quantify and compare the energy, economic, and environmental aspects of products. This paper studied the energy, economic, and greenhouse gas (GHG) emission patterns in broiler chicken farms in the Alborz province of Iran. We studied the effect of the broiler farm size as different production systems on the energy, economic, and environmental indices. Energy use efficiency (EUE) and benefit-cost ratio (BCR) were 0.16 and 1.11, respectively. Diesel fuel and feed contributed the most in total energy inputs, while feed and chicks were the most important inputs in economic analysis. GHG emission calculations showed that production of 1000 birds produces 19.13 t CO2-eq and feed had the highest share in total GHG emission. Total GHG emissions based on different functional units were 8.5 t CO2-eq per t of carcass and 6.83 kg CO2-eq per kg live weight. Results of farm size effect on EUE revealed that large farms had better energy management. For BCR, there was no significant difference between farms. Lower total GHG emissions were reported for large farms, caused by better management of inputs and fewer bird losses. Large farms with more investment had more efficient equipment, resulting in a decrease of the input consumption. In view of our study, it is recommended to support the small-scale broiler industry by providing subsidies to promote the use of high-efficiency equipment. To decrease the amount of energy usage and GHG emissions, replacing heaters (which use diesel fuel) with natural gas heaters can be considered. In addition to the above recommendations, the use of energy saving light bulbs may reduce broiler farm electricity consumption.  相似文献   
122.
Traditional and indigenous knowledge on plants usage is a valuable source of information from cultural and natural perspectives, reflecting society’s complicated and close relationship with the environment. Communities have a valuable source of traditional knowledge on the utilization of natural resources, and it is worth to be documented and preserved for current and future applications. We conducted this research to collect and identify plant species of Karvan District and document the traditional knowledge on their use and consumption values. Regarding the results, 150 plant species are used by local communities, more than 30 % of which are directly consumed as food, 24 % (37 species) are used as medicinal plants, and 16.3 % are applied for decoration purposes; 58.6 % of the species are consumed in the raw form, and the remaining is processed before consumption. Leaves (35 %), seeds (21 %) and flowers (21 %) are the most frequent parts of the plants that are used. High number of young emigrants to industrialized areas in seek of job opportunities is threatening this precious source of indigenous knowledge. Attempts to preserve this empirical source of information by encouraging trans-generational knowledge transmission would help to maintain it for future applications.  相似文献   
123.
Among the methods that are being developed to date for CO2 capture and separation, carbon dioxide adsorption is of great interest due to its low energy consumption, low equipment cost and easiness for application. In this work, a simple method which is easier than existing approaches requiring more complicated and longer computations is presented to accurately predict the carbon dioxide adsorption isotherms for a microporous material as a function of temperature and partial pressure of carbon dioxide. The method appears promising and can be extended for CO2 capture as well as for separation of wide range of adsorbents and microporous materials including several molecular sieves merely by the quick readjustment of tuned coefficients. The proposed method showed consistently accurate results across the proposed pressure and temperature ranges. Predictions showed an average absolute deviation of 1.4% compared to existing Sips and Langmuir equations which show an average absolute deviations of 2.3% and 4%, respectively. The proposed method is superior owing to its accuracy and clear numerical background, wherein the relevant coefficients can be retuned quickly for various cases. This simple-to-use approach can be of immense practical value for the engineers and scientists to have a quick check on adsorption capacities of a given adsorbent at various temperatures and pressures without the necessity of any experimental measurements. In particular, personnel dealing with regulatory bodies of greenhouse gas control and process industries would find the proposed approach to be user friendly involving transparent calculations with no complex expressions.  相似文献   
124.
125.
Heterotopic pregnancy occurs rarely following natural conception; however, intrauterine embryo transfer following in vitro fertilization is a known risk factor for its occurrence. A 29-year-old woman presented with acute abdomen at 14w5d gestation following in vitro fertilization–embryo treatment. A ruptured heterotopic gestation in the left fallopian tube was identified at laparoscopy and treated by salpingectomy. Subsequently, at 21-week gestation, routine sonogram demonstrated bilateral ventriculomegaly in the intrauterine fetus. Fetal magnetic resonance imaging was highly suggestive of ischemic brain injury, most likely attributable to the maternal hypovolemic shock because of ruptured heterotopic gestation. The pregnancy was terminated by intracardiac injection and induction of labor. Timely diagnosis of heterotopic pregnancy requires a high index of suspicion as diagnostic delays can have catastrophic consequences for the mother and/or the intrauterine fetus. © 2015 John Wiley & Sons, Ltd.  相似文献   
126.
This study investigates the feasibility of using recycled high density polyethylene (rHDPE), polypropylene (rPP) and old newspaper (rONP) fiber to manufacture experimental composite panels. The panels were made through air-forming and hot press. The effects of the fiber and coupling agent concentration on tensile, flexural, internal bond properties and water absorption and thickness swelling of wood–fiber plastic composites were studied. The use of maleated polypropylene as coupling agent improved the compatibility between the fiber and both plastic matrices and mechanical properties of the resultant composites compared well with those of non-coupled ones. Based on the findings in this work, it appears that recycled materials can be used to manufacture value-added panels without having any significant adverse influence on board properties. It was also found that composites with rHDPE provided moderately superior properties, compared with rPP samples.  相似文献   
127.
Environmental Science and Pollution Research - Gasoline station attendants spend a great deal of their time in the direct exposure to noxious substances such as benzene and byproducts of gasoline...  相似文献   
128.
The concentration of Cd, Co, Cu, Ni, and Pb was measured in sediment and three fish species collected from Musa Estuary, Persian Gulf. The concentration order of heavy metals in sediment were Ni > Co > Cu > Pb > Cd >. Concentrations of the heavy metals in the fish were apparently different among the three species. The concentrations of Cd and Ni in fish were Johnius belangerii > Euryglossa orientalis > Liza abu, while the Co and Cu levels were L. abu > E. orientalis > J. belangerii and E. orientalis > L. abu > J. belangerii, respectively. Result of regression analysis showed that there were no significant relationships between metal concentration in fish tissues and sediment, except for Ni concentration in the J. belangerii liver. The concentrations of studied metals in fish muscle were below the permissible limits proposed by FAO, WHO, and EC.  相似文献   
129.
Journal of Polymers and the Environment - Chitosan (CS) is a natural biopolymer that due to its excellent properties such as biocompatibility and biodegradability is suitable for use in many...  相似文献   
130.
Environmental Science and Pollution Research - Iran’s agricultural production has expanded significantly in recent years. Environmental pollution caused by the use of energy and chemical...  相似文献   
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