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81.
This paper compared the life cycle inventory (LCI) obtained from three commercial oil palm biomass composting projects in Malaysia which use the open windrow composting system. The LCI was obtained and calculated based on the functional unit of 1 t of compost produced. The input of the inventory are the feed materials such as empty fruit bunches (EFB) and palm oil mill effluent (POME); and utilities which include electricity generated at palm oil mill and diesel used. Composting 2.0–2.5 t of EFB and 5.0–7.5 t of POME required diesel from 218.7 to 270.2 MJ and electricity from 0 to 6.8 MJ. It is estimated that the composting emitted from 0.01 to 0.02 t CO2eq/tcompost mainly from diesel used to operate machineries. Composting saved 65 % of time required for a complete degradation of POME when compared to ponding system, and 89 % of time required for a complete degradation of EFB compared to mulching. In terms of land required, it required 36 % less land as compared to ponding for POME and 99 % less land as compared to mulching for EFB. Based on the case study, diesel was found to be the main contributor to the environmental impact. There is a potential of upgrading the process to be more economical and environmental friendly. Using electricity as the source of energy has a lower footprint for the composting process. Instead of using raw POME, studies had reported that using treated POME either from anaerobic ponding or digested tank can accelerate the composting process.  相似文献   
82.
Environmental Science and Pollution Research - The bioactivity of nanoparticles has engendered a promise in scientific communities for developing novel therapeutic strategies. This study...  相似文献   
83.
Environmental Science and Pollution Research - The daily utilization of a large amount of raw materials is causing a rapid depletion of natural resources. The growth of the human population is...  相似文献   
84.
The effects of acute exposure to 250 mg/kg malathion and the protective effects of 20 mg/kg oleuropein, both administered intraperitoneally, were evaluated in Wistar male rats. Malathion administration increased malondialdehyde, nitric oxide, 8-hydroxy-2′-deoxyguanosine, total oxidant status, and DNA damage, yet decreased total antioxidant activity, superoxide dismutase, and catalase activities in blood, liver, and kidney. Administration of oleuropein reversed malathion-induced oxidative stress, lipid peroxidation, DNA damage, and antioxidant enzyme activity.  相似文献   
85.
Adult males of the quail Coturnix coturnix were exposed to lead acetate trihydrate in drinking water (0.1, 0.25, 0.5, and 1% for one–six months) to investigate histological and histochemical alterations induced by lead intoxication in the liver. Chronic exposure to subtoxic concentrations of lead produced changes in hepatocytes, portal veins, Kupffer cells, and blood sinusoids. Alterations in hepatocytes mainly involved cytoplasmic vacuolation, necrosis, cytolysis, and glycogen accumulation. Kupffer cell hyperplasia, hemosiderosis, blood sinusoidal dilatation, portal vein congestion, and edema were also observed. No fibrosis or cirrhosis in the liver of any member of the dose groups over the entire period of the study was noted. The findings revealed that chronic exposure to lead produced mild histological and histochemical changes in the liver of the quail Coturnix coturnix.  相似文献   
86.
Coastal areas are among the most highly populated, most exploited areas and vulnerable ecosystems in the world. How these interface areas between terrestrial and marine environments can effectively planned and managed has proved to be extremely challenging. Integrated Coastal Zone Management (ICZM) has been promoted as a potential panacea for the effective planning and management of these areas. However achieving such goals for ICZM is complex because of the many human activities and diverse regulatory regimes in coastal areas requires effective integration along many dimensions. Within the context of the developing world, which is often characterised by highly centralised governance systems combined with a lack of effective public and stakeholder participation in planning delivering an effective ICZM, which is drawn from collaborative planning ideas has proved particularly problematic. Furthermore within these countries there have been few critical and analytical evaluations of why ICZM experiments have failed. This paper seeks to begin to address this gap by suggesting that Actor Network Theory (ANT) is an appropriate analytical framework to critically evaluate why ICZM initiatives in Egypt, at both the national and local level, have been relatively unsuccessful. The critical evaluation leads to some practical recommendations that could help to enhance the implementation of ICZM in Egypt.  相似文献   
87.

Background

Hepatitis B virus (HBV) infection is a global public health problem. It is estimated that there are more than 300 million HBV carriers in the world.

Aim

The study aimed to examine the sero-prevalence of hepatitis B virus (HBV) markers among health care workers (HCWs) in Public Teaching Hospitals in Khartoum State, in the year 2004.

Methods

The study is an observational, cross sectional, facility-based study. It was conducted on stratified two-stage cluster random sample of 843 subjects. The study followed non-parametric statistical methods, using Z-test for single proportion.

Results

Among the 843 subjects tested for all HBV markers (Anti-HBc, HBsAg, HBsAb, and HBeAg), the prevalence of Anti-HBc, HBsAg, HBsAb, and HBeAg was found to be 57% (CI 95%:53-60%), 6% (CI 95%:4.0-8.0%), 37% (CI 95%:34-40%) and 9% (CI 95%:7-11%) respectively. P < 0.05.

Conclusion

Seroprevalence of all HBV markers (P < 0.05) was found to be significantly high, while the rate of immunity against HBV infection was low among health care workers In Public Teaching Hospitals in Khartoum State, Sudan.  相似文献   
88.
This paper presents a fuzzy logic-based tool for assessing the pollution concentration of effluents generated by various industrial and commercial activities. The study proposes a fuzzy overall pollution compliance index (FOPCI) (range 0–100) to classify the wastewater discharged from various types of properties present in Ajman, United Arab Emirates. The work mainly focused on three types of pollution that can occur at the inlets of the wastewater treatment plant of Ajman, due to discharge of industrial and commercial effluents, namely pH pollution, salt pollution, and organic pollution. The proposed FOPCI integrates six characteristics, namely pH, Cl?, SO4 2?, conductivity, chemical oxygen demand (COD), and fats, oils, and greases (FOG) values into a readily understandable scale. The FOPCI is developed by using the Fuzzy Inference System Toolbox available in MATLAB in two steps, in which during the first step, three sub-indices, namely fuzzy pH compliance index, fuzzy salt compliance index, and fuzzy organic compliance index are developed. It is then processed in the second stage to develop the FOPCI. Fuzzy rules are used to classify effluents quality into six categories based on the concentration of pollutant in the effluent, namely “Excellent Quality”, “Good Quality”, “Acceptable Quality”, “Moderately Polluting”, “Highly Polluting”, and “Extremely Polluting”. This linguistic classification using fuzzy logic will be helpful as a decision support system to provide an outline for the prioritization of plans for wastewater management based on the values of the indices developed.  相似文献   
89.
In this paper, some key aspects and definitions of exergy are presented, and practical examples are given in order to highlight its usefulness in design, analysis and performance improvement for various types of energy processes for better environment and sustainable development. The relations between exergy, sustainability and environmental impact are illustrated to show how improving the performance of the process through exergy efficiency affects the environmental impact and sustainable development. Both exergy and energy efficiencies for various systems/processes are also studied for comparison purposes.  相似文献   
90.
This review summarizes the environmental occurrence of new brominated flame retardants (NBFRs) and organophosphate compounds (OPs) in the environment of developing countries since 2000. The ban on the production and use of commercial formulations of polybrominated diphenyl ethers (PBDEs) have paved the way for the high use of NBFRs and OPs in consumer products to fulfill the fire safety regulations. Recent studies have shown that the ever increasing production volumes and extensive use of these chemicals as additive FRs and plasticizers have resulted into their ubiquitous occurrence in all environmental compartments. Although presumed to be safe for use and the environment, recent studies on their occurrence and persistence in the environment have raised questions. Due to the lack of awareness, research interest, and availability of technical facilities, limited scientific data is available on the occurrence of these chemicals in developing countries. In this study, we collected reported data and provide an overview of environmental occurrence of NBFRs and OPs in abiotic and biotic matrices of different developing countries. Finally, research gaps were identified with recommendations for future research work and would be useful towards the environmental management of these toxic chemicals.  相似文献   
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