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Ganie Showkat Ali Ali Akbar Mir Tariq Ahmad Mazumdar Nasreen 《Journal of Polymers and the Environment》2022,30(2):504-515
Journal of Polymers and the Environment - Niacin, an essential B-complex vitamin, used in the treatment of nonalcoholic fatty liver disease is the first perceived lipid regulating medication,... 相似文献
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《Waste management (New York, N.Y.)》2002,22(6):691
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The exchange of NO, NO2 and O3 at the soil surface wasmeasured with automatic dynamic chambers in a spruce forest and in abeech forest during periods of several months.NO was emitted from the soil at a rate of0–8 ng N m-2 s-1(spruce) and 0–15 ng Nm-2 s-1(beech), but there was no simple relationship between the flux andeither soil temperature or soil moisture. NO2 and O3 weredeposited at the soil surface. Deposition velocities forNO2were on average 0.3 mm s-1 (spruce) and 0.1 mms-1(beech), and the deposition velocities of O3 were on average 1.6 mm s-1 (spruce) and 1.4 mm s-1 (beech). The depositionvelocity of O3 is fairly constant whereas the deposition velocityof NO2 varies greatly, but the reasons remain to be investigated. 相似文献
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This article accounts for the use of mercury (Hg) in differentactivities in Stockholm during the time period 1795–1995.Turnover of Hg is estimated to 122–440 tons, amounts recycled: 27–50 tons and total emissions of Hg are estimated to 90–390 tons. The stock was approximately 4.4–8.1 tons in 1995. 19th century handicraft occupations and medical treatment emitted alarge part of the Hg, emission sources that hitherto have beenunknown in Sweden. Emissions peaked around 1960, thereafter theemissions plummeted, being the result of decreased use of Hg fordental fillings and in products such as batteries, while recycling efforts had a limited effect on reducing total emissions. Based on this finding, the current focus on collectionof Hg containing products for long term storage in bedrock is questioned. If the aim is to reduce the potential for environmental hazards because of Hg it might be better to focusmore attention on the already emitted amounts since these are nearly 30 times greater than the amount of Hg in stock. 相似文献
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I. K. P. Tan E. S. Stuart R. W. Lenz R. C. Fuller 《Journal of Polymers and the Environment》1998,6(2):67-71
It is well known that Pseudomonas oleovorans can utilize sodium octanoate for both cell growth and the synthesis of polyhydroxyalkanoates (PHAs), but it can utilize sodium butyrate only for limited cell growth and not for the polyester formation when this substrate is the sole carbon source. Therefore, these two substrates were evaluated as cofeeds for the possible incorporation of 3-hydroxybutyryl groups in the resulting PHA. When sodium butyrate and sodium octanoate were fed to P. oleovorans as cosubstrates in various proportions, the resultant cell density and polymer content were proportional to the amount of sodium octanoate in the feed. The PHA extracted from cells grown in all combinations of these cosubstrates had similar unit compositions of approximately 8 mole % 3-hydroxyhexanoate, 91 mole % 3-hydroxyoctanoate and 1 mole % 3-hydroxydecanoate. 3-Hydroxybutyrate units were not detected in any of the PHAs isolated, indicating that these units could not be incorporated in the copolymer synthesized by P. oleovorans either because the cell did not synthesize that monomer or, if it did, the PHA synthase could not copolymerize it with the longer chain monomers. 相似文献
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Chung Y. S. Kim H. S. Jugder D. Natsagdorj L. Chen S. J. 《Water, Air, & Soil Pollution: Focus》2003,3(2):5-19
Monitoring of the occurrence of sandstorms and dustfallphenomena from 1997 to 2000 was carried out. We refer tosandstorms, duststorms and blowing sand as the phenomenaoccurring in the source region, while significant dustfall is thephenomenon that occur in the sink area. It was noted that while the sandstorms in deserts and loess in NW-N China and Mongolia occurred any time during the year while severe sandstorms occurred frequently from March to May after the springthaw. The wind erosion in the source region usually occurred withwind speeds greater than 8 ms-1. However, severe sandstorm phenomenon occurred with wind greater than 15 ms-1 for at least 3 hr or more. In the source regions, sandstorms occurred over60–120 days per year. In Mongolia, the observation of thenumber of sandstorm days decreased due to the increase in rainy days.When a dust cloud from a desert reached the sink region,significant dustfall in the Korean Peninsula occurred due tothe lack of strong winds. We defined the episode ofsignificant dustfall (SD) with the following values: TSP250, PM10 190 g m-3 and visibility 6.5 km or less. In Korea, 8–12 episodes of SD occurred per yearwith 12 to 22 SD days. The maximum concentrations of TSP recorded were 989–1396 g m-3 with PM10 values of 861–996 g m-3 and with the lowestvisibility of 1.4–1.6 km. 相似文献
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PCDDs/DF and Co-PCB (dioxin) formations were studied with ash from a newly developed gasification and melting process for
municipal solid waste. Ash samples were heated in a laboratory-scale fixed-bed reactor. Emphasis was placed on the effects
of the type and composition of ash, temperatures, gas residence time, and gaseous organic precursors. Investigations using
macroscopic and homologue distribution analyses led to the following conclusion. The ash from the gasification–melting process
had the ability to generate dioxins in flue gas. A possible carbon source is unburned carbon in the ash samples, although
this was very low (less than 0.01%). An experimental result that the level of dioxins generated from preheated fly ash obtained
from a conventional incinerator was much lower than that from nonheated fly ash supported this conclusion. Dioxin concentrations
obviously showed temperature dependence and peaked at 350°C. Dioxins formed in a gasification–melting process ash were readily
desorbed from the surface, probably because of the low carbon content of the ash. There was no experimental evidence that
gaseous organic precursors fed to the reactor generated dioxins. Therefore, an organic precursor was not essential for the
formation of dioxins. A good linear relationship obtained between PCDDs/DFs and gas residence time also supported the assumption.
Received: February 14, 2000 / Accepted: June 30, 2000 相似文献
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Takashi Fujimori Akifumi Eguchi Tetsuro Agusa Nguyen Minh Tue Go Suzuki Shin Takahashi Pham Hung Viet Shinsuke Tanabe Hidetaka Takigami 《Journal of Material Cycles and Waste Management》2016,18(4):599-607
Used lead–acid battery (ULAB) recycling has caused numerous health and environmental issues in developing countries. Surface soil pollution from ULAB recycling activities has been linked with elevated levels of lead in human blood. We measured surface soil lead in and surrounding the ULAB recycling village of Hung Yen in northern Vietnam in 2011, 2013, and 2014. The data were analyzed statistically and discussed with respect to distance from the contamination source, year of measurement, contamination pathway, and countermeasures against the contamination. Transportation routes from the smelter or collection site displayed the greatest concentration of surface soil lead (median 6400–10,000 mg/kg). Surface soil lead decreased significantly with distance along the road from the ULAB recycling site, although such a decrease was not observed for rice fields, agricultural roads, or garden soil. Re-suspension and adherence by traffic were identified as key pollution pathways. Distance from the source, covering of the surface of roads, construction of walls, and position relative to the source were shown to be the most effective factors in the reduction of surface soil lead pollution. Application of a combination of these measures should result in improvement in the health of residents. 相似文献
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The size and isotopic behavior of sulfur pools in210Pb-dated peat cores were investigated to obtain aninsight into retention mechanisms of pollutant S in twomountain-top peatlands of the Northern Czech Republic, CentralEurope. The bogs were situated 40 km apart in an area whichbetween the years 1985 and 1995 received as much as 130 kg Sha-1 yr-1 from the atmosphere. Vertical peataccretion was faster at Pod Jelení horou (JH) than atVelký moál (VM). Organic carbon-bonded S was themost abundant sulfur pool, constituting 77 and 65 wt. % at JHand VM, respectively. At JH both the S concentration maximumand the highest annual S deposition rate were displaceddownward by more than 20 years (from 1987 to the 1960s)indicating that the buried S is vertically mobile. At VM the Sconcentration was the highest in the topmost 2-cm section eventhough atmospheric S deposition peaked in 1987. Differentmechanisms of S isotope redistribution prevailed in thetopmost peat layers at JH, where a negative 34Sshift occurred, and at VM, where a positive 34Sshift occurred. Bacterial sulfate reduction was responsiblefor the negative 34S shift at JH. One possibleexplanation of the positive 34S shift at VM isrelease of 32S-enriched products of mineralization duringpeat diagenesis. There was a strong positive correlationbetween the abundance of total and pyrite S along the profiles.The presence of pyrite S at VM (526 ± 60 ppm) suggestedthat even at VM bacterial sulfate reduction occurred. Ananaerobic incubation of JH peat indicated sulfate reductionrate of 600 nmol g-1 day-1. The turnover times forinorganic S pools were shorter than for the organic S pools.Cumulative S contents in the Czech peat bogs were found to besignificantly lower than in similar sites in the NortheasternU.S., even though the atmospheric S inputs were more thanthree times higher at the Czech sites. Possible causes of suchdiscrepancy are discussed. 相似文献
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《Spill Science & Technology Bulletin》1999,5(1):75-80
An ongoing chemical and ecotoxicological study of Water Accommodated Fraction of oils is presented and the preliminary findings are discussed. The study aims at obtaining improved and realistic data on potential environmental effects of various oils released and weathered at sea. Such data will be used for improving algorithms in present fate and effect models for damage assessment studies and “Net Environmental Benefit Analysis” of response alternatives in various spill scenarios. Preliminary results show that models used to assess effects in the water column will need to resolve the water soluble fraction of oils into more than one single bulk parameter to produce realistic estimates of effects. 相似文献
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Green composite fibers (339?C612?nm in diameter) have been developed from wood pulp, acetylated wood pulp and polyethylene oxide under various concentrations by electrospinning process. A polymer solution concentration of 7 wt% with 5 wt% wood pulp have been found to produce uniform composite fibers. Scanning electron microscopy micro-images demonstrated that composite fibers diameter and morphology depended on the processing parameters, such as solution concentration and molecular weight of polymer. Transmission electron microscopy and laser confocal microscopy observations indicated that the acetylated wood was well dispersed and oriented along the length of composite fibers axis. X-ray diffraction studies revealed that the structure of electrospun composite fibers became more non-crystalline. 相似文献
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火焰原子吸收法测定底质中总铜,铅,锌,镉,铬的探讨 总被引:1,自引:0,他引:1
采用样品一次消解,直接火焰原子吸收法测定底质中总铜,铅,锌,镉,铬,测定方法的相对偏差≤4.5%,加标回收率为91.8%-106.0%,标准参考样的测定值符合要求。 相似文献
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Ali A. H. Dakroury G. A. Hagag M. S. Abdo Sh. M. Allan K. F. 《Journal of Polymers and the Environment》2022,30(3):1170-1188
Journal of Polymers and the Environment - In this study, Acrylic acid (AA), acrylamide (AM), and 16,16-dimethylheptadecan-1-amine (PJM-T) were copolymerized using gamma irradiation with 60Co... 相似文献
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施粉煤灰农田和作物的锰,镁,锌,镍,钒和锂含量变化及影响评价 总被引:1,自引:0,他引:1
锰和镁是地壳中的常量元素,也是动植物和人体保持生命活动的必需元素,锌,镍,钒则是动植物不可缺少的微量元素,这些元素若含量过高则也会产生危害。施用粉煤灰未使土壤中这些元素的含量发生明显变化,所产植物中也未有异常富集。施灰田作物根部的锂含量较高,但其茎和果实的锂含量很低,不影响安全食用。 相似文献
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