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991.
In an urban-transit bus,fueled by biodiesel in Toledo,Ohio,single inhalable particle samples in October 2008 were collected and detected by scanning electron microscopy and energy dispersive X-ray spectrometry(SEM/EDS).Particle size analysis found bimodal distribution at 0.2 and 0.5 μm.The particle morphology was characterized by 14 different shape clusters:square,pentagon,hexagon,heptagon,octagon,nonagon,decagon,agglomerate,sphere,triangle,oblong,strip,line or stick,and unknown,by quantitative order.The square particles were common in the samples.Round and triangle particles are more,and pentagon,hexagon,heptagon,octagon,nonagon,decagon,strip,line or sticks are less.Agglomerate particles were found in abundance.The surface of most particles was coarse with a fractal edge that can provide a suitable chemical reaction bed in the polluted atmospheric environment.The three sorts of surface patterns of squares were smooth,semi-smooth,and coarse.The three sorts of square surface patterns represented the morphological characteristics of single inhalable particles in the air inside the bus in Toledo.The size and shape distribution results were compared to those obtained for a bus using ultra low sulfur diesel. 相似文献
992.
Phthalate esters in water and sediments of the Kaveri River,India: environmental levels and ecotoxicological evaluations 总被引:3,自引:0,他引:3
993.
994.
Amesho Kassian T. T. Lin Yuan-Chung Mohan S. Venkata Halder Subham Ponnusamy Vinoth Kumar Jhang Syu-Ruei 《Environmental Chemistry Letters》2023,21(1):183-230
Environmental Chemistry Letters - The global energy demand has been projected to rise over 28% by 2040, calling for more renewable resources such as lignocellulosic biomass to produce biofuels, and... 相似文献
995.
Rajendran Devi Sri Chidambaram Ashok Kumar Ponnusamy Senthil Venkataraman Swethaa Muthusamy Shanmugaprakash Vo Dai-Viet Nguyen Rangasamy Gayathri Vaithyanathan Vasanth Kumar Vaidyanathan Vinoth Kumar 《Environmental Chemistry Letters》2023,21(2):911-934
Environmental Chemistry Letters - Modern biomass and organic waste are becoming major, carbon-neutral sources of fine chemicals, biomolecules and fuels to replace fossil fuel products. As a... 相似文献
996.
Gautam Aparna Khajone Vijay B. Bhagat Pundlik R. Kumar Sushil Patle Dipesh S. 《Environmental Chemistry Letters》2023,21(6):3105-3126
Environmental Chemistry Letters - Diminishing petroleum reserves, increasing carbon emissions, and the growing demand for fuels are calling for alternative fuels. Global diesel consumption... 相似文献
997.
This research examined relationships between alternative measures of affect and supervisory performance ratings. The first study showed that dispositional rather than state affect significantly predicted supervisory ratings of performance over time. Since the measures of affect differed on both content and temporal dimensions, a follow‐up study was conducted to explicate the results. The second study found that a pleasantness‐based measure of dispositional affect (Berkman, 1971a) again predicted rated performance over time, but activation‐based measures of both dispositional and state affect (using PANAS scales) were not predictive of supervisory evaluations of performance. The implications of these findings in terms of research on affect and the longstanding pursuit of the happy–productive worker are discussed. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
998.
Problem
This study considers whether requiring learner drivers to complete a set number of hours while on a learner license affects the amount of hours of supervised practice that they undertake. It compares the amount of practice that learners in Queensland and New South Wales report undertaking. At the time the study was conducted, learner drivers in New South Wales were required to complete 50 hours of supervised practice while those from Queensland were not.Method
Participants were approached outside driver licensing centers after they had just completed their practical driving test to obtain their provisional (intermediate) license. Those agreeing to participate were interviewed over the phone later and asked a range of questions to obtain information including socio-demographic details and amount of supervised practice completed.Results
There was a significant difference in the amount of practice that learners reported undertaking. Participants from New South Wales reported completing a significantly greater amount of practice (M = 73.3 hours, sd = 29.12 hours) on their learner license than those from Queensland (M = 64.1 hours, sd = 51.05 hours). However, the distribution of hours of practice among the Queensland participants was bimodal in nature. Participants from Queensland reported either completing much less or much more practice than the New South Wales average.Summary
While it appears that the requirement that learner drivers complete a set number of hours may increase the average amount of hours of practice obtained, it may also serve to discourage drivers from obtaining additional practice, over and above the required hours.Impact on Industry
The results of this study suggest that the implications of requiring learner drivers to complete a set number of hours of supervised practice are complex. In some cases, policy makers may inadvertently limit the amount of hours learners obtain to the mandated amount rather than encouraging them to obtain as much practice as possible. 相似文献999.
Shrivastava JN Satsangi GP Kumar A 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(1):125-126
Prevalence of keratinophilic fungi was observed in paddy field soil during different stages of cultivation viz., transplanting, tillering, milking and maturation. Out of total 76 soil samples, 65 soil samples were found to be positive for the keratinophilic fungi. Fourteen species belonging to a single genus Chrysosporium were isolated through out the cropping season. C. keratinophilum (17.1%) followed by C. tropicum (13.15%) were found to be the most dominating geophilic species. The highest percent distribution of keratinophilic fungi appeared during the milking stage (100%) of paddy cultivation, followed by the maturation stage (89.47%). 相似文献
1000.
Banu JR Yeom IT Esakkiraj S Kumar N Logakanthi S 《Journal of environmental biology / Academy of Environmental Biology, India》2008,29(2):143-146
Sago, the tapioca starch is manufactured by over 800 small-scale units located in the Salem district, Tamil Nadu, India. During the processing of sago it generates huge quantities of biodegradable solid waste, as crushed tubers. In present study an attempt was made to convert these biodegradable solid sago tubers into value added compost using an exotic earthworm, Eudrilus eugeniae. The experiments were carried out in a plastic tray at various concentrations of sago-sludge (50% 75% and 100%) for a period of 90 days. During the vermicomposting, data were collected on life form (cocoon, non clitellates, clitellates) of earthworm and it was found to be high in 50% followed by 75% and 100% concentrations. Chemical analysis of worked substrates showed a step wise increase of nitrogen and phosphorus. The fold increase of phosphorus and nitrogen were found to be high for sago-sludge undergoing vermicomposting than the control. During the composting period the organic carbon decreased from its initial value of 58, 76 and 107 mg/kg to 21, 24 and 65 mg/kg for 50, 70 and 100%, respectively The microbial analysis showed that after 75 days of composting, their population stabilized and further increase in composting period did not increase their population size. The results indicate that 50% and 75% concentration of sludge mixed with bedding material was ideal for the vermicomposting. 相似文献