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221.
222.
Palaniselvam Kuppusamy Solachuddin J.A. Ichwan Narasimha Reddy Parine Mashitah M. Yusoff Gaanty Pragas Maniam Natanamurugaraj Govindan 《环境科学学报(英文版)》2015
In this present study, we reported broccoli (Brassica oleracea L.) as a potential candidate for the synthesis of gold and silver nanoparticles (NPs) in green chemistry method. The synthesized metal nanoparticles are evaluated their antimicrobial efficacy against different human pathogenic organisms. The physico-chemical properties of gold nanoparticles were analyzed using different analytical techniques such as a UV-Vis spectrophotometer, Field Emission Scanning Electron Microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction and a Fourier Transform Infrared spectrophotometer. In addition, gold and silver NP antimicrobial efficacy was checked by disc diffusion assay. UV-Vis color intensity of the nanoparticles was shown at 540 and 450 nm for gold and silver nanoparticles respectively. Higher magnification of the Field Emission Scanning Electron Microscopy image shows the variable morphology of the gold nanoparticles such as spherical, rod and triangular shapes and silver nanoparticles were seen in spherical shapes. The average spherical size of the particles was observed in 24- 38 nm for gold and 30-45 nm for silver NPs. X-ray diffraction pattern confirmed the presence of gold nanoparticles and silver nanoparticles which were crystalline in nature. Additionally, the functionalmetabolites were identified by the Fourier TransformInfrared spectroscopy. IR spectra revealed phenols, alcohols, aldehydes (sugar moieties), vitamins and proteins are present in the broccoli extract which are accountable to synthesize the nanoparticles. The synthesized gold and silver NPs inhibited the growth of the tested bacterial and fungal pathogens at the concentration of 50 μg/mL respectively. In addition, broccoli mediated gold and silver nanoparticles have shown potent antimicrobial activity against human pathogens. © 2015 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. 相似文献
223.
Hideyuki Tagaya Yu-ichi Suzuki Naomi Komuro Jun-ichi Kadokawa 《Journal of Material Cycles and Waste Management》2001,3(1):32-37
Model compounds of phenol resin were reacted in sub- and supercritical water to clarify the mechanism of the decomposition
reaction of plastics in water. Cleavage reaction of methylene bonds was confirmed in the reactions of model compounds of phenol
resin such as bis(hydroxyphenyl)methanes in sub- and supercritical water under an Ar atmosphere, although the methylene bond
was stable in thermal reactions. It was also confirmed that sub- and supercritical water played important roles not only as
a stable solvent thermally, but also as a chemical reagent.
Received: July 19, 2000 / Accepted: September 14, 2000 相似文献
224.
M. L. Shonouda R. M. Farrag O. M. Salama 《Journal of environmental science and health. Part. B》2013,48(3):347-356
Abstract Effects of the botanical extract (myrrh), Commiphora molmol, and the sublethal treatments of profenofos/chlorofluazuron, fenvalerate and pyriproxyfen on the larvae of S. littoralis were investigated. The results showed that myrrh induced the highest activity after 7 days of treatment with concentration of 10000 ppm and the percentage of mortality reached 44.4%. The chemical insecticide profenofos/chlorofluazuron appeared to be the most effective treatment, giving a mortality of 54% after one day of treatment with a concentration of 100 ppm. Different treatments showed adverse effects on pupation, emerging adults and larval duration. The highest concentration of myrrh (10000 ppm) induced 35% pupation. No pupa was obtained with profenofos/chlorofluazuron while fenvalerate and pyriproxyfen gave 13.3% at 50 ppm. At 10000 ppm of myrrh, 25% adult was emerged, also fenvalerate and pyriproxyfen decreased the emerging moth to 13.3% at 50 ppm. For control there was no larval mortality at 7 days and the percentages of pupation and adult emergence were 90%. Bioassays were also conducted to test the joint action of myrrh applied in binary mixtures with each chemical insecticide on Spodoptera larvae. Results of the bioassay of mixtures indicated antagonistic effects on larval mortality. However, combination of myrrh with profenofos/chlorofluazuron showed additive effect. Also, the degree of pupation and emerging moth varied considerably when myrrh combined with the chemical insecticides. The present work shows the strong efficacy of the botanical extract (myrrh) which could be used alone or in combination with sublethal doses of certain insecticides to control the cotton leafworm. 相似文献
225.
《International Journal of Sustainable Engineering》2013,6(4):233-239
ABSTRACTThe high-performance carbon fibres can be recycled from waste carbon fibre/epoxy resin composites by supercritical n-butanol. Recycling experiment designed by response surface method was used to investigate quantitative relation between degradation rate of epoxy resin and process parameters. Thus, the optimum process parameters could be obtained, and effects of process parameters and layers on degradation rate and mechanical performance of the recycled carbon fibres were analysed. The tensile strength of the recycled carbon fibre under the optimum process parameters was 94.53% of that of the original carbon fibre, tensile modulus was 93.57% of that of the original carbon fibre and interfacial shear strength was 90% of that of the original carbon fibre. 相似文献
226.
The power sector in Thailand is the largest contributor to CO2 emissions. There is high potential to mitigate CO2 emission via alternative power generating plants. Alternative plants considered in this study include nuclear plants, integrated gasification combined cycle plants, biomass-based plants and supercritical thermal power plants. The biomass-based plants considered here are fueled with four types of biomass; paddy husk, municipal solid waste (MSW), fuel wood and corncob. The methodology for the optimal expansion plan of the power generating system over the planning horizon is based on the least-cost approach. The results from the least-cost planning analyses show that the nuclear alternative has the highest potential to mitigate not only CO2 but also other airborne emissions. Moreover, the nuclear option is the most effective abatement strategy for CO2 reduction due to its negative incremental cost of CO2 reduction. 相似文献
227.
《International Journal of Green Energy》2013,10(6):423-437
The LCA emissions from four renewable energy routes that convert straw/corn stover into usable energy are examined. The conversion options studied are ethanol by fermentation, syndiesel by oxygen gasification followed by Fischer Tropsch synthesis, and electricity by either direct combustion or biomass integrated gasification and combined cycle (BIGCC). The greenhouse gas (GHG) emissions of these four options are evaluated, drawing on a range of studies, and compared to the conventional technology they would replace in a western North American setting. The net avoided GHG emissions for the four energy conversion processes calculated relative to a “business as usual” case are 830 g CO2e/kWh for direct combustion, 839 g CO2e/kWh for BIGCC, 2,060 g CO2e/L for ethanol production, and 2,440 g CO2e/L for FT synthesis of syndiesel. The largest impact on avoided emissions arises from substitution of biomass for fossil fuel. Relative to this, the impact of emissions from processing of fossil fuel, e.g., refining of oil to produce gasoline or diesel, and processing of biomass to produce electricity or transportation fuels, is minor. 相似文献
228.
Tad?W.?PatzekEmail author S.-M.?Anti R.?Campos K.?W.?ha J.?Lee B.?Li J.?Padnick S.-A.?Yee 《Environment, Development and Sustainability》2005,7(3):319-336
It is shown here that one burns 1 gallon of gasoline equivalent in fossil fuels to produce 1 gallon of gasoline equivalent
as ethanol from corn. When this corn ethanol is burned as a gasoline additive or fuel, its use amounts to burning the same
amount of fuel twice to drive a car once. Therefore, the fuel efficiency of those cars that burn corn ethanol is halved. The
widespread use of corn ethanol will cause manifold damage to air, surface water, soil and aquifers. The overall energy balance
of corn conversion to ethanol demonstrates that 65% of the input energy is lost during the conversion. Carbon dioxide sequestration
by corn is nullified when corn ethanol is burned, and there will be additional carbon dioxide, nitrous oxides, and sulfur
oxide emissions from the fossil fuels used to produce the ethanol.
Students in the Spring 2003 CE24 Freshman Seminar offered at U.C. Berkeley by the Civil and Environmental Engineering Department
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
229.
230.
柑橘皮中果胶提取条件的研究 总被引:7,自引:0,他引:7
利用酸性水解乙醇沉淀法提取果胶,分别测定了不同的浸泡时间、酸碱度及水解温度对果胶产率的影响.结果表明:浸泡时间与水解时间过长或过短,酸碱度及水解温度过高或过低,果胶的产率均不高,只有浸泡时间在2h左右、水解时间在2~2.5h、pH在2~3之间、水解温度在80~95℃时果胶的得率最大. 相似文献