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111.
Abstract

Paper electrophoretic movements of a number of pesticides belonging to organophosphorus, organochlorine and pyethroid groups in various acid background electrolytes have been studied. The effect of pH and pKa of the acids on the movement of these pesticides have also been studied. It has been observed that the movement of most of the pesticides is enhanced with increase in the degree of ionisation of the acids (pKa) studied as background electrolytes. The movement also increases with increase in the pH of acids. On the basis of differential movement of pesticides towards cathode and anode, a number of separations have been achieved from binary mixtures. Monocrotophos, rogor and malathion have been determined quantitatively (28.6 ‐ 29.2 μg) in alcoholic extracts of soil samples.  相似文献   
112.
Healthcare waste management (HCWM) options are inconsistent in Bangladesh. One of the first critical steps in the process of developing a reliable waste management plan requires a comprehensive understanding of the quantities and characteristics of the waste that needs to be managed. This study took into consideration both the quantity and quality of the generated waste to determine the generation rates and physical properties of healthcare waste (HCW) in Chittagong Medical College Hospital (CMCH) and also to estimate the amount of infectious and non-infectious waste generated in different wards. CMCH, the second largest hospital in Bangladesh, comprises 34 wards, 12 of which were selected randomly. Waste materials were collected from these wards and then segregated and weighed. Waste generation per day was found to be 73.22 kg/ward, 1.28 kg/bed and 0.57 kg/patient. A total of 2490 kg of HCW was produced each day in CMCH (37% being infectious and the rest being non-infectious waste). Infectious waste was 27.07 kg per ward, 0.47 kg per bed and 0.21 kg per patient and the non-infectious waste was 46.15 kg per ward, 0.81 kg per bed and 0.36 kg per patient per day. HCW comprised eight categories of waste materials with vegetable/food waste being the largest component (50.21%) and varied significantly (P < 0.05) among the 12 different wards studied. The greatest amount of HCW was recorded (154 kg) in Orthopaedics followed by 96.66 kg in the Medicine Unit-3 and the smallest amount was recorded in Casualty (8.79 kg). The amount of HCW was positively correlated with the number of occupied beds (rxy = 0.79, P < 0.01). There is no structured form of medical waste treatment in CMCH and most waste materials are dumped in open areas for natural degradation or re-sold by scavengers. It is essential to develop a national policy and implement a comprehensive action plan for HCWM that will provide environmentally sound technological measures to improve HCWM in Bangladesh.  相似文献   
113.
Environmental Science and Pollution Research - The hydrophobicity of silica and composite aerogels has enabled them to acquire applications in a variety of fields. With remarkable structural,...  相似文献   
114.
Environmental Science and Pollution Research - Carbon dioxide emission and climatic variation have a detrimental influence on the atmosphere as well as on agriculture production. The key aim of the...  相似文献   
115.
In the current study, the chemistry of fresh and stored rainwater of Thar Desert, Pakistan, was estimated during two consecutive monsoon periods. The present research deals with the variation in physicochemical parameters, total arsenic (Ast), inorganic arsenic species (Asi, AsV, AsIII), and fluoride (F?) in stored rainwater (SRW) at different time intervals (1 week to 3 months). The pH of fresh rainwater (FRW) samples showed slightly acidic to neutral in nature (6.08–7.06) which were inconsistent with the reference pH value (5.6) of rainwater. The resulted data indicated that Ast and F? levels in SRW were enhanced with time duration. The levels of Ast and F? in SRW after different time intervals were found in the range of 194–683 μg/L and 10–35.4 mg/L, respectively. The values of Ast and F? were 20–70 and 7–24 times higher than those of WHO permissible limits, 10 μg/L and 1.5 mg/L, respectively. The AsIII was dominant species in SRW, which corresponds to >60 % of Asi. The characteristics of the SRW revealed an unacceptable quality to consume for drinking and agricultural purposes in the studied area.  相似文献   
116.
Creation of food-based nanomaterials for food processing and packaging applications is actually gaining in importance. Indeed, the design of a suitable food carrier system controls the encapsulation efficiency, the product stability and release of bioactives such as micronutrients, antimicrobial compounds and antioxidants. The smaller size of nanomaterials provides higher thermodynamic and kinetic stability. Whereas the higher surface area enhances compound solubility. Nanoemulsions both encapsulate bioactive compounds effectively and address the food safety concerns of the fresh produce associated with foodborne pathogens. Nanoliposomes encapsulate bioactive whey peptides and fat-soluble vitamins with improved functionalities. Encapsulated bioactive molecules are released by diffusion into the surrounding environment after degradation of the surrounding polymeric matrix.  相似文献   
117.
The industrial sector is the biggest electricity consumer in Malaysia. Electric motors account for more than 45% of the electricity consumption in the industrial sector in the country. Therefore, it is very important to implement energy efficiency standards for electric motors to reduce energy consumption growth in this sector. This paper attempts to calculate the cost efficiency analysis and emission reduction by implementing energy efficiency standards for electric motor in Malaysia. The energy efficiency standards are proposed based on the efficiency of electric motors from survey data. The study examines the potential energy, economical and environmental impacts of the implementation of energy efficiency standards for electric motors in three scenarios i.e. 0.5%, 1.0% and 1.5% of standards efficiency improvement. Standards also enable consumers to reduce their electricity bill and contribute to a positive environmental impact.  相似文献   
118.
There is a concern that mismanagement of medical waste in developing countries may be a significant risk factor for disease transmission. Quantitative estimation of medical waste generation is needed to estimate the potential risk and as a basis for any waste management plan. Dhaka City, the capital of Bangladesh, is an example of a major city in a developing country where there has been no rigorous estimation of medical waste generation based upon a thorough scientific study. These estimates were obtained by stringent weighing of waste in a carefully chosen, representative, sample of HCEs, including non-residential diagnostic centres. This study used a statistically designed sampling of waste generation in a broad range of Health Care Establishments (HCEs) to indicate that the amount of waste produced in Dhaka can be estimated to be 37 ± 5 ton per day. The proportion of this waste that would be classified as hazardous waste by World Health Organisation (WHO) guidelines was found to be approximately 21%. The amount of waste, and the proportion of hazardous waste, was found to vary significantly with the size and type of HCE.  相似文献   
119.
120.
This study reports concentrations of polybrominated diphenyl ethers (PBDEs) in dust samples collected from 17 homes in Kuwait. PBDEs were measured in all homes investigated with mean summation operatorPBDEs concentration ranging from 1 to 393 ng g(-1), with a geometric mean of 76 ng g(-1). The dominant congener in all samples was BDE 209 constituting ca. 85% of the summationPBDEs followed by BDE 99 (5%), BDE 47 (4.5%), and BDE 183 (2%). The congener mixture in dust is dominated by those in deca and penta formulations. Using the measured concentrations and estimates of dust ingestion rates for children and adults, estimated human non-dietary exposure based on mean PBDE levels were 14.8 and 1.5 ng day(-1) for children and adults, respectively. The 10-fold difference in exposure estimates between children and adults in this study supports previous reports that children are at greater risk from pollutants that accumulate indoors. The ubiquitous distribution of these chemicals as noted in this study highlights the fact that we are continuously exposed to low doses of chemicals in the indoor environment.  相似文献   
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