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871.
Man’s increased demand for food and better living conditions has led to over exploitation of resources and the consequent generation of enormous amounts of liquid and solid waste materials. This is one of the global challenges for mankind. In Malaysia, palm oil mill waste (POMW) contributes the highest proportion of industrial solid wastes produced yearly. Wastes from the mills include palm oil mill effluent, decanter cake, empty fruit bunches, seed shells and the fibre from the mesocarp. Direct application of POMW into agricultural soil has resulted in a number of problems such as water pollution, leaching. However, with application rates specific for targeted plant species, land application can be employed as a permanent solution to the problem of waste from palm oil mills. This review examines the characteristics of each of the palm oil wastes and their potential for use as a future fertilizer supplement.  相似文献   
872.
The aim of the present study is to study the effect of γ-dose rate on the biodegradation of γ-sterilized polyolefins. Films of isotactic polypropylene, high density polyethylene and ethylene-propylene (EP) copolymer were sterilized under γ-radiation with doses of 10 and 25 kGy. Two different 60Co sources were used with dose rate 600 and 780 Gy h−1. Neat and sterilized samples were incubated in compost and fungal culture environments. The changes in functional groups, surface morphology and intrinsic viscosity in polymer chains were characterized by FT-IR spectroscopy, SEM and viscometric measurements, respectively. It was observed that both γ-degradation and biodegradation processes depend on the dose rate of γ-source. It was found that the biodegradation of γ-sterilized polyolefins in composting and microbial culture environments increased with decreasing the γ-dose rate.  相似文献   
873.
ABSTRACT

In the era of developing technologies, there is always been a crisis of rising demands of energy. There is no skepticism that a lot of energy is being produced every hour for almost each and every field, but still an exploration is needed to come up with new and viable options for energy creation. The same is the objective of this paper which proposes the use of waste biomaterials in association with organic and inorganic materials as a source of energy to power up small electronic devices. In this research egg shell membrane (ESM)-based triboelectric nanogenerator (TENG) is proposed in combination with calotropis (Calo), cellulose from fruit of Bombax Ceiba (BOM), cellulose in form of tissue paper (TISU), dog hair (DH), polytetrafluoroethylene (PTFE), aluminum (Al), and copper (Cu). ESM is eco-friendly waste food by-product and available in abundance. Characterization of ESM is done by scanning electron microscope (SEM), atomic force microscope (AFM), X-ray diffraction (XRD), and Fourier transform infrared spectrophotometer (FTIR). The proposed ESM-PTFE-based TENG power up 462 green LEDs (462 × 2 V = 924 V ~ 1 kV) without rectifier and produced up to 7.61 µJ energy with 4.7 µF capacitor at 200 tapings. All the proposed ESM-based TENG combinations generate sufficient voltage to turn ON the wrist watch. This green-energy-based TENG has potential application in various fields especially related to medical devices.  相似文献   
874.
India is the first country to introduce environmental legislation in the constitution but because of lengthy legal procedures, it is very difficult to control environmental deterioration. There are many factors responsible for this deterioration. Coal mining is one such activity where deterioration is very severe and the present communication aims this aspect. Coal is the one of the most essential mineral having large reserves in India. It’s mining and beneficiation produce a variety of pollutants. The main pollutants emitted during the processing of coal are green house gases, coal dust and acid mine drainage. Many reports on different aspects of coal mining are available including reports on emission of different pollutants but the present work is probably only of it’s kind in which the authors have tried to determine environment liability directly in terms of economy. It was found that greenhouse liabilities, coal dust liability and sulphur liability are accounted for 12.07, 5.0 and 101.97 US$, making an overall 2.4% of the total economic gains due to coal mining. During the calculations approximate number of total workers and other parameters have been taken into consideration. Who pays for this irreversible damage is a question. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
875.
Open crop stubble burning events were observed in and around Patiala city, India. A ground level study was deliberated to analyze the contribution of wheat (Triticum aestivum) and rice (Oriza sativa) crop stubble burning practices on concentration levels of aerosol, SO2 and NO2 in ambient air at five different sites in and around Patiala city covering agricultural, commercial and residential areas. Aerosols were collected on GMF/A and QMF/A (Whatman) sheets for a 24 h period throughout the year in 2007. Simultaneously, sampling of SO2 and NO2 was conducted and results obtained during stubble burning periods were compared to the non-stubble burning periods. Results clearly pointed out a distinct increase in aerosol, SO2 and NO2 levels during the crop stubble burning periods.  相似文献   
876.
The cultivation of white rot edible fungus Pleurotus florida was performed in polybags. The corn cob was employed as basal substrate while eight different additives such as urea, ammonium sulphate, gram flour, soybean meal, ground nut cake and molasses were used with corn cob. Three different levels of variable combinations with corn cob were evaluated in response to different parameters of mushroom viz., mycelial growth, spawn running, primordial initiation, fruit body yield and its biological efficiency. Each additive at different combinations showed variable impact on the different stages of mushroom life cycle. The primordial initiation was observed for the first time during 20.2–35.1 days. The biological efficiencies in every supplemented set were increased over un-supplemented control set. Increasing the level of additives, the biological efficiency was negatively affected at higher levels. The cotton seed cake was found the best supplement producing 93.75% biological efficiency while soybean meal was the second best additive producing 93.00% yield. The highest growth rate, rapid mycelia run, early primordial initiation, highest yield and biological efficiency were recorded in the combination of corn cob and cotton seed cake at 2% (98 + 2) level.  相似文献   
877.
Review of fluoride removal from drinking water   总被引:9,自引:0,他引:9  
Fluoride in drinking water has a profound effect on teeth and bones. Up to a small level (1–1.5 mg/L) this strengthens the enamel. Concentrations in the range of 1.5–4 mg/L result in dental fluorosis whereas with prolonged exposure at still higher fluoride concentrations (4–10 mg/L) dental fluorosis progresses to skeletal fluorosis. High fluoride concentrations in groundwater, up to more than 30 mg/L, occur widely, in many parts of the world. This review article is aimed at providing precise information on efforts made by various researchers in the field of fluoride removal for drinking water. The fluoride removal has been broadly divided in two sections dealing with membrane and adsorption techniques. Under the membrane techniques reverse osmosis, nanofiltration, dialysis and electro-dialysis have been discussed. Adsorption, which is a conventional technique, deals with adsorbents such as: alumina/aluminium based materials, clays and soils, calcium based minerals, synthetic compounds and carbon based materials. Studies on fluoride removal from aqueous solutions using various reversed zeolites, modified zeolites and ion exchange resins based on cross-linked polystyrene are reviewed. During the last few years, layered double oxides have been of interest as adsorbents for fluoride removal. Such recent developments have been briefly discussed.  相似文献   
878.
This study investigated phosphate-induced lead immobilization from different Pb minerals in soils under varying pHs. Four soils were used, including one Pb-contaminated soil (NC-Soil) and three soils spiked with litharge (PbO), cerrusite (PbCO3), or anglesite (PbSO4), referred to as PbO-soil, PbCO3-soil, and PbSO4-soil, respectively. The soils were equilibrated with KCl and Ca(H2PO4)(2).H2O under pH of 3-7. At low pH (3 and 5), Pb solubility followed PbO-soil>PbCO3-soil>PbSO4-soil; while at pH=7, it was PbSO4-soil>PbO-soil>PbCO3-soil. Phosphate decreased Pb dissolution time from >180 to <60 min and reduced soluble Pb by 67-100%. This was mostly via transformation of Pb minerals into chloropyromorphite [Pb(5)(PO(4))(3)Cl]. Our results indicated that P addition can effectively transform various Pb minerals into insoluble chloropyromorphite in soils. This transformation was more significant at acidic condition (e.g., pH相似文献   
879.
Arunachal Pradesh in northeastern India is considered a biocultural diversity hotspot, with diverse tribal peoples and immense floral and faunal diversity. This rich diversity, sustained through the morang (community forests) and jhum (slash and burn) cultivation systems, is the backbone of native communities’ livelihood security. Kebung (Ratufa bicolor) and other squirrel species are intricately related to biocultural systems of the Adi people of Arunachal Pradesh. Primary surveys and participatory rural appraisals were carried out in 20 villages of East Siang and Upper Siang districts of the state. Results indicated that Kebung squirrels are hunted from successional forests, including from morang and jhum lands. They are an integral part of the Adi sociocultural, economic and livelihood systems, being used for food, medicinal, ceremonial and other purposes. Hunting methods vary in the traditional and transitional Adi villages. Recently, kebung populations have diminished, and this is attributed to overhunting. In particular, a decrease in kebung populations in some morang and jhum habitats has threatened the biocultural resources of the Adi. Knowledge and management practices relating to kebung hunting are gradually eroding among the younger Adi generations. However, the community recently passed a resolution for kebung conservation, supported by the customary norms. We conclude with a discussion of policy requirements for sustainable management of kebung populations to maintain Adi biocultural and livelihood security.  相似文献   
880.
Rapid industrialization and economic developments have increased the tropospheric ozone (O3) budget since preindustrial times, and presently, it is supposed to be a major threat to crop productivity. Maize (Zea mays L.), a C4 plant is the third most important staple crop at global level with a great deal of economic importance. The present study was conducted to evaluate the performance of two maize cultivars [HQPM1: quality protein maize (QPM)] and [DHM117: nonquality protein maize (NQPM)] to variable O3 doses. Experimental setup included filtered chambers, nonfiltered chambers (NFC), and two elevated doses of O3 viz. NFC+15 ppb O3 (NFC+15) and NFC+30 ppb O3 (NFC+30). During initial growth period, both QPM and NQPM plants showed hormetic effect that is beneficial due to exposure of low doses of a toxicant (NFC and NFC+15 ppb O3), but at later stages, growth attributes were negatively affected by O3. Growth indices showed the variable pattern of photosynthate translocation under O3 stress. Foliar injury in the form of interveinal chlorosis and reddening of leaves due to increased production of anthocyanin pigments was observed at higher concentrations of O3. One-dimensional gel electrophoresis of leaves taken from NFC+30 showed reductions of major photosynthetic proteins, and differential response was observed between the two test cultivars. Decline in the number of male flowers at elevated O3 doses suggested damaging effect of O3 on reproductive structures which might be a cause of productivity losses. Variable carbon allocation pattern particularly to husk leaves, foliar injury, and damage of photosynthetic proteins led to significant reductions in economic yield at higher O3 doses. PCA showed that both the cultivars responded more or less similarly to O3 stress in their respective groupings of growth and yield parameters, but magnitude of their response was variable. It is further supported by difference in the significance of correlations between variables of yield and AOT40. Cultivar response reflects that QPM performed better than NQPM against elevated O3.  相似文献   
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