黄渤海气溶胶光学厚度的多源卫星遥感产品精度分析和时空分布特征研究

以黄渤海上空大气为目标研究区,基于AERONET观测网,获取该区域2015-2017年的气溶胶光学厚度(AOD)实测数据,并对可见红外成像辐射计VIIRS,中分辨率成像光谱仪MODIS,静止水色卫星成像仪GOCI与新一代地球同步气象卫星AHI H8的AOD遥感产品展开精度验证.同时,利用长时间的遥感影像探究并分析AOD...     

Enhanced catalytic complete oxidation of 1,2-dichloroethane over mesoporous transition metal-doped γ-Al2O3

High-surface-area mesoprous powders of γ-Al₂O₃ doped with Cu^2 +, Cr^3 +, and V^3 + ions were prepared via a modified sol–gel method and were investigated as catalysts for the oxidation of chlorinated organic compounds. The composites retained high surface areas and pore volumes comparable with those of undoped γ-Al₂O₃ and the presence of the transition metal ions enhanced their surface acidic properties. The catalytic activity of the prepared catalysts in the oxidation of 1,2-dichloroethane (DCE) was studied in the temperature range of 250–400°C. The catalytic activity and product selectivity were strongly dependent on the presence and the type of dopant ion. While Cu^2 +- and Cr^3 +-containing catalysts showed 100% conversion at 300°C and 350°C, V^3 +-containing catalyst showed considerably lower conversion. Furthermore, while the major products of the reactions over γ-alumina were vinyl chloride (C₂H₃Cl) and hydrogen chloride (HCl) at all temperatures, Cu- and Cr-doped catalysts showed significantly stronger capability for deep oxidation to CO₂.     

Effect of calcium against salinity-induced inhibition in growth, ion accumulation and proline contents in Cichorium intybus L

This study assesses the effect of NaCl (80 and 160 mM) and CaCl2 (10 mM) solutions, alone and in combination, to 30-day-old seedlings of Cichorium intybus L. Observations were made at 30 day intervals from the time of treatment till harvest (180 days after sowing). Application of NaCI resulted in significant decreases in lengths of root and stem, in dry weights of root, stem and leaves and in the leaf area, as compared with control. The reduction was less with the combined application of NaCI and CaCI2 than with the NaCI treatment alone. On the contrary treatment of CaCl2, alone promoted the above variables. Proline content in the leaves was enhanced with NaCl and CaCI, alone as well as with the NaCI + CaCI2 treatments; the maximum (six-fold) enhancement was observed with the combined treatments, compared with NaCl (four-fold increase) and CaCl2 (two-fold increase) alone. The sodium (Na+) and Chloride (CI) contents in different plant parts increased both with NaCI and with NaCI+ CaCI2 treatments. The maximum accumulation was observed in leaves, followed by that in stem and root. The potassium (K+) and calcium (Ca2+) contents decreased under NaCl stress, but increased with CaCI2 treatment. Thus, calcium ameliorated the deleterious effects of NaCI stress and stimulated the plant metabolism and growth.     

Effect of Pb,Cd and Cu on survival and development of Culex quinquefasciatus (Diptera: Culicidae)

ABSTRACT

The present research aimed to determine the lowest levels of three heavy metals (Pb, Cd and Cu) to which the larvae of Southern House Mosquito, Culex quinquefasciatus are susceptible in water. The study also aimed to investigate the effects of these heavy metals on the development of Cx. quinquefasciatus at concentrations set by Pakistan Environmental Protection Agency (Pak-EPA) as permissible levels for liquid industrial effluents. The 2nd instar larvae of Cx. quinquefasciatus were exposed to different concentrations of Pb, Cd and Cu and their effects on oviposition preference, egg hatching rate and larval development were studied. The LC₅₀ values of Pb, Cd and Cu were 12.6, 6.3 and 2.6?ppm, respectively. Gravid female mosquito adults deposited a significantly lower number of egg rafts in containers containing 0.50?ppm Pb or 1.0?ppm Cu in water. Each of the heavy metals in water resulted in significantly (p?<?0.05) lower egg hatching rate, prolonged time to pupation, lower pupation rate, prolonged time to adult emergence, lower adult emergence rate and higher female to male ratio. It is concluded that the 2nd instar larvae of Cx. quinquefasciatus are susceptible to Pak-EPA permissible levels of Pb, Cd and Cu in municipal and liquid industrial effluents.     

Silica nanoparticles synthesis and applications in agriculture for plant fertilization and protection: a review

Environmental Chemistry Letters - The rapidly rising population is calling for the production of more food, yet biotic and abiotic stresses caused by pests and climate change...     

Survey on readability of online information for upgrading understandability of biomass energy technology

Waste management contributes to renewable energy such as biodiesel production from processes of various types of biomass including vegetable oils, animal fats, and waste of edible oil. Successful waste management effort is influenced by people concern about benefit of waste management including for renewable energy from biomass. It involves their understanding initiated by literacy on biomass energy. To help increase literacy on waste recycle and biomass energy technology, we study readability of online information regarding biomass energy in Indonesian language (Bahasa Indonesia). Indonesia is considered as one of biomass-rich country with a little utilization for energy. The readability is studied by combining two approaches: measurement by readability standard and survey on readability confirming measurement by the standard. This study focuses on the confirmation survey readability standard measured on biomass online information in Indonesian language. In the survey, 19 online text materials were read by respondents and they were asked to give their impression whether the texts are easy or difficult to understand. From this study, what factors influence understandability of text information are shown. The results could be a guidance for preparing text information to raise people concern on waste recycle and renewable energy in general.     

Selection of palm oil mill effluent treatment for biogas generation or compost production using an analytic hierarchy process

Palm oil mill effluent (POME) is the liquid waste from palm oil mills, and is generally treated using open lagoon technology. However, open lagoons can also be combined with more environmentally friendly technologies. In this study, the analytic hierarchy process (AHP) was used to determine the best combination open lagoon of technology (COLT) for POME treatment. The selected criteria were benefit, opportunity, risk, and cost, with sub-criteria further determined based on these criteria. The sub-criteria were revenue, greenhouse gas reduction, employment absorption, corporate social responsibility, co-processing, environmental risk, marketing risk, technology reliability, investment cost, operation and maintenance cost, and opportunity cost. The alternatives were COLT-composting for fertilizer purpose and COLT-biogas for energy generation purpose. Calculation and analysis was performed on questionnaire data using Expert Choice^®. COLT-composting proved to be the superior COLT using tentative performance of alternative in this research, with advantages in benefit, opportunity, and risk. The priority weight for COLT-composting was 0.636. Sensitivity analysis was performed by changing criteria priorities. For COLT-biogas to be considered better than COLT-composting, the cost would need to be weighted more than 0.954.     

The impact of municipal solid waste treatment methods on greenhouse gas emissions in Lahore, Pakistan

The contribution of existing municipal solid waste management to emission of greenhouse gases and the alternative scenarios to reduce emissions were analyzed for Data Ganj Bukhsh Town (DGBT) in Lahore, Pakistan using the life cycle assessment methodology. DGBT has a population of 1,624,169 people living in 232,024 dwellings. Total waste generated is 500,000 tons per year with an average per capita rate of 0.84kg per day. Alternative scenarios were developed and evaluated according to the environmental, economic, and social atmosphere of the study area. Solid waste management options considered include the collection and transportation of waste, collection of recyclables with single and mixed material bank container systems (SMBCS, MMBCS), material recovery facilities (MRF), composting, biogasification and landfilling. A life cycle inventory (LCI) of the six scenarios along with the baseline scenario was completed; this helped to quantify the CO2 equivalents, emitted and avoided, for energy consumption, production, fuel consumption, and methane (CH4) emissions. LCI results showed that the contribution of the baseline scenario to the global warming potential as CO2 equivalents was a maximum of 838,116 tons. The sixth scenario had a maximum reduction of GHG emissions in terms of CO2 equivalents of -33,773 tons, but the most workable scenario for the current situation in the study area is scenario 5. It saves 25% in CO2 equivalents compared to the baseline scenario.     

Emergency preparedness through game playing

The lack of emergency preparedness in Mauritius has been the cause of many tragedies. Our approach to tackle this problem was by developing an emergency preparedness game layered and fused with a disaster warning and guidance system that emanates clarity to the unfathomable bearings of emergencies and natural disasters. The emergency preparedness game is based on a selection of diverse real life-threatening difficulties that entail different strategies aimed at bettering the survival instincts of users. It uses story-telling scenarios along with in-game footnotes that yield directives on how to brave fierce and unpredictable calamities. The game reinforces a sense of self-composedness and suppressing untimely fears of users in horrendous circumstances. With regard to the warning system, it unremittingly feeds users with notifications during emergencies, that encases shortest escape routes to lead them to safe locations via a fully functional GPS map. This application brings some novelties that are virtually non-existent in related applications. For instance, this application includes a warning and guidance system, a 3D scenario game to prepare its users for disasters, an interactive survival toolkit selection, an SMS rescue feature and a mass notification system via the web.     

Recycling polymeric waste from electronic and automotive sectors into value added products

The environmentally sustainable disposal and recycling of ever increasing volumes of electronic waste has become a global waste management issue. The addition of up to 25% polymeric waste PCBs (printed circuit boards) as fillers in polypropylene (PP) composites was partially successful: while the tensile modulus, flexural strength and flexural modulus of composites were enhanced, the tensile and impact strengths were found to decrease. As a lowering of impact strength can significantly limit the application of PP based composites, it is necessary to incorporate impact modifying polymers such as rubbery particles in the mix. We report on a novel investigation on the simultaneous utilization of electronic and automotive rubber waste as fillers in PP composites. These composites were prepared by using 25 wt.% polymeric PCB powder, up to 9% of ethylene propylene rubber (EPR), and PP: balance. The influence of EPR on the structural, thermal, mechanical and rheological properties of PP/PCB/ EPR composites was investigated. While the addition of EPR caused the nucleation of the β crystalline phase of PP, the onset temperature for thermal degradation was found to decrease by 8%. The tensile modulus and strength decreased by 16% and 19%, respectively; and the elongation at break increased by ~71%. The impact strength showed a maximum increase of ~18% at 7 wt.%–9 wt.% EPR content. Various rheological properties were found to be well within the range of processing limits. This novel eco-friendly approach could help utilize significant amounts of polymeric electronic and automotive waste for fabricating valuable polymer composites.

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