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1.
Fish is a key source of protein for many households in Ghana. It is also an essential source of income to many households in the coastal communities of Ghana. The importance of the fisheries sector to the socio-economic development of the country cannot be over emphasised. Women dominate the fishing value chain in Ghana but paradoxically, the study of their activities has not attracted the attention of researchers and policy makers. This study examined the processing and sale of smoked marine fish and its effects on the livelihood of women in Mfantseman Municipality. The survey was conducted in four communities. A sample size of 363 was drawn from women in the industry and institutions whose activities are related to the industry. The data were analysed using quantitative and qualitative methods. Findings from the study revealed that the industry offers employment opportunity for the majority of women in the municipality, and it is an important source of income to them. Further, the industry has potentials for reducing poverty and enhancing economic empowerment of women in the district. However, women in the industry are confronted with challenges which include health risks that erode whatever gains made by them. The study concludes that the municipal assembly must spearhead and provide a conducive environment for this economic activity to flourish as a way of reducing poverty among women in the municipality.  相似文献   
2.
Biohythane production via single-stage anaerobic digestion (AD) is an effective way for sustainable energy recovery from lignocellulosic biomass. In this paper, biohythane was produced through the AD process from pineapple peel waste substrate using purely cultured Methanosarcina mazei with the enhancement of palm oil mill effluent (POME) sludge as the inoculum. This study focuses on the effects of the lignocellulosic pre-treatment method, the addition of POME sludge into M. mazei culture medium as inoculum, and various operational conditions (food to microorganisms (F/M) ratios, temperature, pH) on gas production performances. The experimental results indicate that these parameters influenced the efficiency of biohythane production by producing the peak maximum biohythane production rate values (HPRmax) and (MPRmax), H2:CH4 = 1.93:0.67 L/L-d, and biohythane yield (HY) and (MY), H2:CH4 = 1.18:0.55 mL/L-substrate. This study demonstrates that biohythane gas (H2 + CH4 + CO2) production from pineapple waste can be accelerated by M. mazei only with the enhancement of POME sludge through single-stage AD system under mesophilic batch process conditions.  相似文献   
3.
Abstract

Cement manufacturing is a process that results in the emission of significant quantities of suspended particulate matter (SPM) to the ambient air. An environmental forensic investigation was carried out in the surroundings of a major cement manufacturing unit at a place called Coimbatore in the southern Indian state of Tamil Nadu. The investigation was carried out to identify the contribution of the cement manufacturing unit to the SPM concentration of the surrounding air environment. The sampling points’ selection and sample collection were done following the principles outlined in the INTERPOL Manual for Pollution Crime Forensic Investigation. On-site monitoring of the air samples was carried out using Mini Laser Aerosol Spectrometer (GRIMM, Mini-LAS Model 11R). The instrument was capable of measuring particles ranging from 0.25 to 32 µm and classifying them into 31 size channels. The test results at majority of the monitoring locations were well above the limits specified in the National Ambient Air Quality Standards of India. Microscopic studies of the dust samples were carried out for surface texture and particle shape. The spatial distribution of particles was analysed using geographic information system (GIS) for the visual identification of the extent of the pollution by keeping the cement factory as the focal point. The results from the GIS and microscopic analysis established the role of the cement factory in the particulate matter pollution of its surroundings, specifically in the areas North-West of the factory. The successfully adopted procedure can serve as a guideline for the environmental forensic investigation of similar pollution incidences.  相似文献   
4.
The present study is aimed at assessing the ability of Bacillus sp.JDM-2-1 and Staphylococcus capitis to reduce hexavalent chromium into its trivalent form.Bacillus sp.JDM-2-1 could tolerate Cr(Ⅵ) (4800 μg/mL) and S.capitis could tolerate Cr(Ⅵ) (2800 μg/mL).Both organisms were able to resist Cd2+ (50 μg/mL),Cu2+ (200 μg/mL),Pb2+ (800 μg/mL),Hg2+ (50 μg/mL) and Ni2+ (4000 μg/mL).S.capitis resisted Zn2+ at 700 μg/mL while Bacillus sp.JDM-2-1 only showed resistance up to 50 μg/mL.Bacillus sp.JDM-2-1 and S.capitis showed optimum growth at pH 6 and 7,respectively,while both bacteria showed optimum growth at 37℃.Bacillus sp.JDM-2-1 and S.capitis could reduce 85% and 81% of hexavalent chromium from the medium after 96 h and were also capable of reducing hexavalent chromium 86% and 89%,respectively,from the industrial effluents after 144 h.Cell free extracts of Bacillus sp.JDM-2-1 and S.capitis showed reduction of 83% and 70% at concentration of 10 μg Cr(Ⅵ)/mL,respectively.The presence of an induced protein having molecular weight around 25 kDa in the presence of chromium points out a possible role of this protein in chromium reduction.The bacterial isolates can be exploited for bioremediation of hexavalent chromium containing wastes,since they seem to have the potential to reduce the toxic hexavalent form to its nontoxic trivalent form.  相似文献   
5.
The building sector has been regarded as a potential sector where there is large capacity to reduce the climate change effect. This study has proposed solutions to mitigate environmental impacts and achieve low CO2 emission from residential sector. Therefore, full life cycle assessment (LCA) has been run to assess the CO2 emission and its effect on the atmosphere and climate change. Based on the result, timber scheme is the best choice due to releasing less CO2 emissions to the atmosphere. However, house builders in Malaysia have almost completely neglected timber as a building material, with timber use as building components reduced to 5%. In this study, LCA Software was used to assess CO2 emissions from different wall construction. The alternative building scheme has been made by reinforce steel stud, wooden beam and timber wall (S8) to improve the scheme deficiency while releasing less CO2 emissions compared to other schemes. Therefore, S8 has a decreased CO2 effect by 85% less than precast concrete frame and 90% less than brick over their lifetime. (S8) increased the load bearing compared to conventional timber beam. Thus, new scheme S8 could be replaced by current scheme and promote more adjustable scheme for Malaysian housing.  相似文献   
6.
7.

Yearly, huge amounts of sock refuse are discarded into the environment. Socks contain many molecules, and worn ones, which are rich in smell-causing bacteria, have a strong influence on animals’ behaviors. But the impacts of sock odor on the oviposition behavior of dengue vectors are unknown. We assessed whether Aedes albopictus changes its oviposition activity in response to the presence of used socks extract (USEx) in potential breeding grounds, using choice and no-choice bioassays (NCB). When furnished even chances to oviposit in two sites holding USEx and two others containing water (control), Ae. albopictus deposited significantly less eggs in USEx than in water sites. A similar pattern of oviposition preference was also observed when there were more oviposition options in water. When there were greater oviposition opportunities in USEx sites, Ae. albopictus oviposited preferentially in water. Females laid significantly more eggs during the NCB involving water than USEx. Also, significantly more mature eggs were retained by females in the NCB with USEx than in that with water. These observations strongly suggest the presence of molecules with either repellent or deterrent activities against Ae. albopictus females and provide an impetus to advocate the integration of used socks in dengue control programs. Such applications could be a realistic end-of-life recourse to reroute this waste from landfills.

  相似文献   
8.
Environmental Science and Pollution Research - The aim of this study is to investigate the effect of the polymethyl acrylate (PMA) additive on the formation of particulate matter (PM) and nitrogen...  相似文献   
9.
The objective of this work was to isolate cellulose nanocrystal (CNC) from oil palm fronds (Elaeis guineensis) and its subsequent characterization. Isolation involves sodium hydroxide/anthraquinone pulping with mechanical refining followed by total chlorine free bleaching (includes oxygen delignification, hydrogen peroxide oxidation and peracetic acid treatment) before acid hydrolysis. Bleaching significantly decreased kappa number and increased α-cellulose percentage of fibers as confirmed by Technical Association of the Pulp and Paper Industry standards. Transmission electron microscopy (TEM), X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetric analysis revealed that acid hydrolysis along with bleaching improved crystallinity index and thermal stability of the extracted nanocrystals. It was observed that CNC maintained its cellulose 1 polymorph despite hydrolysis treatment. Mean diameter as observed by TEM and average fiber aspect ratio of obtained CNC was 7.44 ± 0.17 nm and 16.53 ± 3.52, respectively making it suitable as a reinforcing material for nanocomposite.  相似文献   
10.
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