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排序方式: 共有622条查询结果,搜索用时 15 毫秒
101.
Abstract Application of fungal agents to develop eco-friendly and cost-effective dye removal from textile effluent was studied. A fungal strain Neurospora sp has been isolated from effluent site and tested for its ability to biosorption and biodegrade azodyes. Biosorption of azo dyes by live and dead fungal biomass was evaluated. Percentage of decolorization was found to be effective against all tested azodyes and ranges between 33 and 76%. Nearly 72% of azo dyes were removed by dead Neurospora sp biomass and 86% respectively by live active biomass. Biodegradation of textile effluent by Neurospora sp showed changes in BOD, COD and TOC indicates that isolated Neurospora sp effectively degrade and utilize the dye as a sole carbon source. The initial TOC of 2600?mg/L was approximately reduced to almost its three fourth within a week. Research works on application of fungal biomass on textile effluent treatment have proven decolorizing potential among a wide range of anionic and cationic dyes. Based on the results, the biosorption mechanism by Neurospora sp was observed as effective, economic and eco-friendly decontaminant. 相似文献
102.
In this study, a novel film structure of corn zein coated on polypropylene (PP) synthetic films for food packaging applications was developed, and the mechanical properties of the resulting coated film, as affected by the coating formulation, were investigated. Composite structures of PP films coated with corn zein were obtained through a simple solvent casting method. Different amounts of corn zein (5 and 15%) were dissolved in 70 and 95% aqueous ethanol solution at 50°C. Solutions of corn zein plasticized with poly(ethylene glycol) and glycerol (GLY) at various levels (20 and 50%) were applied on corona‐discharge‐treated PP. A statistical analysis based on full factorial design was performed to examine the influence of the coating formulation on the final properties of the corn‐zein‐coated PP films. A significant (p < 0.05) improvement in the coated film's mechanical properties was observed compared to those of the uncoated PP. The effect of the plasticization of the coating solutions was also quite significant. In general, GLY provided better improvements in the mechanical properties of the corn‐zein‐coated PP films. The statistical analysis of the results showed that the corn‐zein and plasticizer concentrations and plasticizer type used in the coating formulations were more effective parameters and had significant effects on the mechanical behavior of the coated PP films. In conclusion, corn‐zein coatings could have potential as alternatives to conventional synthetic polymers used in composite multilayer structures for food packaging applications. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
103.
Vinod N. DhageM.L. Mane M.K. BabrekarC.M. Kale K.M. Jadhav 《Journal of Alloys and Compounds》2011,509(12):4394-4398
The nanocrystalline Cr3+ substituted barium hexaferrite having generic formula BaFe12−xCrxO19 (where x = 0.00, 0.25, 0.50, 0.75, and 1.00) samples were synthesized by sol-gel auto-combustion technique. The precursors were prepared by using stoichiometric amounts of Ba2+, Fe3+ and Cr3+ nitrate solutions with citric acid as a chelating agent. The metal nitrate to citric acid ratio was taken as 1:2 while pH of the solution was kept at 8. The thermal decomposition of nitrate-citrate gels of as-prepared powder was investigated by TG/DTA. The as-prepared powder of BaFe12−xCrxO19 was sintered at 900 °C for 8 h. The sintered powder was characterized by XRD, EDAX, SEM and VSM technique. The pure barium hexaferrite shows only single phase hexagonal structure, while for the samples at x = 0.25, 0.50, 0.75 and 1.00 shows α-Fe2O3 peaks with M-phase of barium hexaferrite. The lattice parameters (a and c) decreases with increase in chromium content x. The particle size obtained from XRD data is in the range of 30-40 nm which confirms the nanocrystalline nature of the samples. The magnetic properties were investigated by means of vibrating sample magnetometer (VSM) technique. The saturation magnetization (Ms), remanence magnetization (Mr), coercivity (Hc) and magneton number (nB) decreases with increase in chromium content x. 相似文献
104.
Chemical looping reforming (CLR) is a new technology for syngas generation. The theoretical process design aspects of syngas generation using CLR of isooctane (gasoline) are studied in this paper to assess its ability for fuel processor development for solid oxide fuel cells. The fuel processor operating conditions for maximum syngas generation at thermoneutral conditions are determined in this study using nickel oxide as oxygen carrier for different inputs of oxygen carrier within the temperature range of 600–1,000 °C at 1 bar pressure. The thermoneutral temperatures for the dual reactor fuel processor were calculated using the hot product gas stream and exothermic CLR process enthalpy to completely balance the endothermic process requirements. The thermoneutral point of 879.5 °C (NiO input of 7 moles) delivered maximum syngas (13.92 moles) using lowest amount of air (26.13 moles) in the process was found to be the most suitable thermoneutral temperature for the fuel processor operation. The novel fuel processor design can also be used for other fuels and oxygen carriers. 相似文献
105.
See Wan Yan Rajesh Ramasamy Noorjahan Banu Mohamed Alitheen Asmah Rahmat 《International Journal of Food Properties》2013,16(6):1231-1244
Nutritional composition, total phenolic content, total flavonoid, antioxidant capacity, and antioxidant vitamins of bilimbi (Averrhoa bilimbi) and carambola (Averrhoa carambola) were determined and compared in this study. Bilimbi was found to contain higher moisture, ash, carbohydrate, protein, fat, and dietary fiber compared to carambola. Total phenolic content was higher in carambola although bilimbi yielded more total flavonoid. Vitamins A, C, and E contents of bilimbi were also higher than carambola. Antioxidant and scavenging activity as determined by β-carotene bleaching assay and DPPH radical scavenging assay of carambola were significantly (p < 0.05) higher than bilimbi. These results suggested that carambola was a potent natural antioxidant food and that contribution of phenolic compounds to its antioxidant capacity was greater than that of antioxidant vitamins. 相似文献
106.
Ayça Bal Tülin Banu İyim Saadet Özgümüş 《Polymer-Plastics Technology and Engineering》2013,52(10):990-995
Waterborne acrylic emulsion was obtained by using methyl methacrylate, ethyl and butyl acrylate monomers. Emulsions containing nanoparticles were prepared by blending the stable dispersions containing SiO2 or MMT nanoparticles. The films were prepared from emulsions and coating tests were applied. The physical properties of prepared emulsions are better than the commercial emulsions. The addition of the nanoparticles especially SiO2 have positive effect on the resistance to environmental conditions of emulsions. Waterborne acrylic emulsions containing nanoparticles prepared in this study can be used in the manufacturing of the semi-lustrous emulsion type nano paint with low cost, high performance and environmentally friendly. 相似文献
107.
SiO2 thin films are in high demand for wide range of applications including microelectronics, optoelectronics, solar energy conversion, photocatalysis, and self-cleaning coatings. The performance of thin film is strongly influenced by surface properties like surface roughness, thickness, morphology, wetting behavior, and thermal stability. In these applications, the SiO2 sols were prepared using tetraethylorthosilicate as a source of SiO2 and deposited on 100?×?40?×?2?mm3 glass slide using dip-coating method for 2?min and calcined at 250?°C for 30?min. The SiO2 thin films were obtained using DTAB, SDS, and Tween 20 (Tw 20) surfactants with the thickness of 36.92, 47.15, and 52.39?nm, respectively. Surface morphology was studied with AFM and surface roughness was depicted with 0.9528, 3.6534, and 0.9294?nm. Contact angle measurements have been performed with goniometer to evaluate the wetting behavior of the film. The contact angle of 58.01°, 48.40°, and 37.88° was observed with SDS, DTAB, and Tw 20 film, respectively. The SiO2 thin films with SDS showed more surface roughness and water repelling ability when compared to DTAB and least with Tw 20. 相似文献
108.
This paper aims to show the use of the response surface methodology (RSM) in size optimization of an autonomous PV/wind integrated hybrid energy system with battery storage. RSM is a collection of statistical and mathematical methods which relies on optimization of response surface with design parameters. In this study, the response surface, output performance measure, is the hybrid system cost, and the design parameters are the PV size, wind turbine rotor swept area and the battery capacity. The case study is realized in ARENA 10.0, a commercial simulation software, for satisfaction of electricity consumption of the global system for mobile communications (GSM) base station at Izmir Institute of Technology Campus Area, Urla, Turkey. As a result, the optimum PV area, wind turbine rotor swept area, and battery capacity are obtained to be 3.95 m2, 29.4 m2, 31.92 kWh, respectively. These results led to $37,033.9 hybrid energy system cost, including auxiliary energy cost. The optimum result obtained by RSM is confirmed using loss of load probability (LLP) and autonomy analysis. 相似文献
109.
Mg–Ni multilayers and Ni-rich Mg thin films were deposited by electron gun and pulsed laser deposition, respectively. Samples were submitted to thermal treatment in deuterium or hydrogen atmosphere at 423 K and 105 Pa pressure to promote the metal to hydride phase transition.The H chemical bonding in the multilayer samples, after annealing in H2 atmosphere, was examined by Fourier transform infrared spectroscopy: the obtained spectra suggest that the samples with the Mg:Ni=2:1 atomic ratio contain the Mg2NiH4 phase while the samples with lower Ni concentration contain both the MgH2 and the Mg2NiH4 phases.The effect of the Ni additive on the stability of the deuteride phase was studied by thermal desorption spectroscopy (TDS). The TDS spectra of the single-phase Mg2NiD4 samples show a TDS peak at 400 K. The TDS spectra of the two-phase samples show both the D2 desorption peak at 400 K and a second peak at higher temperature that we attributed to the dissociation of the MgD2 phase. The high-temperature peak shifts to lower temperatures by increasing the Ni content.It is suggested that in the two-phase samples, the lattice volumes having the Mg2Ni structure resulting from the dissociation of the Mg2NiD4 phase reduce the thermodynamic stability of the MgD2 phase. 相似文献
110.
Methods of bio-functionalize silicon nitride involve process steps to convert it into an oxynitride via plasma implantation
techniques. Such methods can potentially damage microstructures such as cantilevers. In this paper, we report successful bio-functionalization
of Hotwire CVD silicon nitride-based piezo-resistive cantilevers without any oxygen plasma treatment. Process to fabricate
such structures and to bio-functionalize them is discussed in detail. 相似文献