WorldWideScience

Sample records for efficient on-site degradation

  1. Efficient on-site construction

    DEFF Research Database (Denmark)

    Thuesen, Christian Langhoff; Hvam, Lars

    2011-01-01

    selected market – optimising cost and value. Based on the platform, the company has managed to create a high-quality product at low cost. In fact, they have managed to reduce costs by more than 30 per cent, enabling the company to sell houses to people that normally would not be able to afford a house...... from the German platform such as: platform does not imply that “off-site manufacturing” is the most optimal production method, rather it is a matter of handling complexity; strong commitment and loyalty from the whole organization is needed; importance of having a specific customer focus (target...... costing); and incremental rather than radical innovation. Originality/value – The findings challenge the predominant understanding of industrialisation of the construction processes, illustrating how substantial improvements can be achieved through platform thinking, on-site production and traditional...

  2. Enabling Efficient Intelligence Analysis in Degraded Environments

    Science.gov (United States)

    2013-06-01

    When facing decisions in underdeveloped, degraded, and denied environments, commanders are likely to rely even more heavily on efficient intelligence ... analysis . Unfortunately, most of the time, the data gathered in these environments will be uncertain, ambiguous, and incomplete. Tools enabling fast

  3. On-Site Enzyme Production by Trichoderma asperellum for the Degradation of Duckweed

    DEFF Research Database (Denmark)

    Bech, Lasse; Herbst, Florian-Alexander; Grell, Morten Nedergaard

    2015-01-01

    was performed on T. asperellum growing on PDA agar, wheat bran and duckweed, respectively. T. asperellum proved to be able to produce a wide enzyme profile, including both depolymerization and debranching enzymes, mainly consisting of hemi-cellulases. The secretome analysis showed specific glycoside hydrolase......-induction on duckweed compared with growth on wheat bran and PDA, including a GH62 $-L-arabinofuranosidase, a promising candidate enzyme for the degradation of duckweed. The enzyme cocktail from T. asperellum proved capable of degrading pretreated duckweed, obtaining up to 60% of the theoretical glucose yield, making...

  4. Long-term hygienic barrier efficiency of a compact on-site wastewater treatment system.

    Science.gov (United States)

    Heistad, Arve; Seidu, Razak; Flø, Andreas; Paruch, Adam M; Hanssen, Jon F; Stenström, ThorAxel

    2009-01-01

    The long-term use of a filter-based, on-site wastewater treatment system increases nutrient discharge to receiving waters and may reduce its hygienic barrier efficiency. The main purpose of this research was to assess the hygienic barrier efficiency and the associated health risks of an on-site system that had exceeded its 5-yr design capacity with respect to phosphorus (P) removal. The system was investigated for bacteria and virus removal and assessed with respect to potential health risks in relation to reuse of effluent for irrigation. The system consists of a septic tank, a pressure-dosed vertical flow biofilter, and an up-flow filter unit with lightweight clay aggregates. The total P concentration in the effluent had increased gradually from initially <0.1 mg P L(-1) during the first 2 yr of operation to 1.8 mg P L(-1) after 5.3 yr. Escherichia coli was used as an indicator organism for fecal bacteria removal, whereas bacteriophages phiX174 and Salmonella typhimurium phage 28B (S.t. 28B) were used to model enteric virus removal. An overall decrease in E. coli removal occurred from a complete (approximately 5.6 log10) reduction during the first 3 yr of operation to 2.6 log10 reduction. The removal amounts of the bacteriophages phiX174 and S.t. 28B were 3.9 and 3.7 log10, respectively. Based on removal of S.t. 28B, the risks of rotavirus infection and disease for the investigated scenarios were above the acceptable level of 10(-4) and 10(-3), respectively, as defined by the World Health Organization.

  5. Kinetic and degradation efficiency of trichloroethylene (TCE) via ...

    African Journals Online (AJOL)

    Kinetic and degradation efficiency of trichloroethylene (TCE) via photochemical process from contaminated water. S Dobaradaran, R Nabizadeh, AH Mahvi, A Noroozi, M Yunesian, N Rastkari, S Nazmara, S Zarei ...

  6. Highly efficient catalytic reductive degradation of various organic ...

    Indian Academy of Sciences (India)

    CeO₂-TiO₂ nano-hybrid along with NaBH₄ exhibited remarkable catalytic activities towards all the probed dyes, namely Methylene Blue, Methyl Orange, Congo Red, Rhodamine B and Malachite Green, with a degradation efficiency of ~100% in ...

  7. [Growth kinetics and phenol degradation of highly efficient phenol-degrading Ochrobactrum sp. CH10].

    Science.gov (United States)

    Chen, Xiao-Hua; Wei, Gang; Liu, Si-Yuan; Sun, Jiang-Man; Wang, Fang-Fang; Li, Hao-Yuan; Liu, Yu-Jun

    2012-11-01

    The strain Ochrobactrum sp. CH10 was a highly efficient phenol degrading bacterial strain isolated from soil in a constructed wetland in Yuan Dynasty Capital City Wall Relics in Beijing. Growth and biodegradation were investigated in details with phenol as the sole carbon and energy source. The best growth and most efficient phenol biodegradation occurred when the strain was cultured in medium containing 400 mg x L(-1) phenol at initial pH of 7.0 and 30 degrees C, with 5% inoculation volume. The phenol degradation rate was around 100% , 92.3 and 82.2% with an initial concentration of 400, 900 and 1 000 mg x L(-1) phenol in 24, 44 and 48 h, respectively. Phenol degradation kinetic studies indicated that the strain followed Haldane's model, and the parameters were: upsilon(max) (maximum specific rate) = 0.126 h(-1), K(s) (half-saturation constant) = 23.53 mg x L(-1) and K(I) (inhibition constant) = 806.1 mg x L(-1). The phenol-limited growth kinetics of CH10 by Andrews's model also followed a similar trend to that of phenol degradation. Among all the strains belonging to Ochrobactrum genus, this strain is the most efficient at present. The strain has a good application potential for the phenolic wastewater treatment.

  8. Comparison of AOPs Efficiencies on Phenolic Compounds Degradation

    Directory of Open Access Journals (Sweden)

    Lourdes Hurtado

    2016-01-01

    Full Text Available In this work, a comparison of the performances of different AOPs in the phenol and 4-chlorophenol (4-CP degradation at lab and pilot scale is presented. It was found that, in the degradation of phenol, the performance of a coupled electro-oxidation/ozonation process is superior to that observed by a photo-Fenton process. Phenol removal rate was determined to be 0.83 mg L−1 min−1 for the coupled process while the removal rate for photo-Fenton process was only 0.52 mg L−1 min−1. Regarding 4-CP degradation, the complete disappearance of the molecule was achieved and the efficiency decreasing order was as follows: coupled electro-oxidation/ozonation > electro-Fenton-like process > photo-Fenton process > heterogeneous photocatalysis. Total organic carbon was completely removed by the coupled electro-oxidation/ozonation process. Also, it was found that oxalic acid is the most recalcitrant by-product and limits the mineralization degree attained by the technologies not applying ozone. In addition, an analysis on the energy consumption per removed gram of TOC was conducted and it was concluded that the less energy consumption is achieved by the coupled electro-oxidation/ozonation process.

  9. A novel lignin degradation bacterial consortium for efficient pulping.

    Science.gov (United States)

    Wang, Yanxia; Liu, Quan; Yan, Lei; Gao, Yamei; Wang, Yanjie; Wang, Weidong

    2013-07-01

    A lignin degradation bacterial consortium named LDC was screened from the sludge of a reeds pond by a restricted subculture. It could break down 60.9% lignin in reeds at 30°C under conditions of static culture within 15 days. In order to analyze the diversity of LDC, plate isolation, 16S rDNA clone library and ARDRA (Amplified Ribosomal DNA Restriction Analysis) were performed. Six bacterial strains were isolated from LDC and eighteen DNA phylotypes were identified from 230 bacterial analyzed clones. They were classified into Clostridiales(9.1%), Geovibrio thiophilus (5.1%), Desulfomicrobium (10.9%), Pseudomonas sp. (25.2%), Azoarcus sp. (5.1%), Thauera (5.1%), Paenibacillus sp. (5.1%), Cohnella sp. (2.2%), Acinetobacter sp. (3.1%), Microbacterium (7.8%), and uncultured bacterium (21.3%). In addition, physical characteristics of paper hand-sheets between biological pretreatment and chemical pretreatment were compared. The results showed that LDC had the capability of lignin degradation and was efficient for pulping, which would provide a new choice for biopulping. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Development of a dynamic headspace gas chromatography-mass spectrometry method for on-site analysis of sulfur mustard degradation products in sediments.

    Science.gov (United States)

    Magnusson, R; Nordlander, T; Östin, A

    2016-01-15

    Sampling teams performing work at sea in areas where chemical munitions may have been dumped require rapid and reliable analytical methods for verifying sulfur mustard leakage from suspected objects. Here we present such an on-site analysis method based on dynamic headspace GC-MS for analysis of five cyclic sulfur mustard degradation products that have previously been detected in sediments from chemical weapon dumping sites: 1,4-oxathiane, 1,3-dithiolane, 1,4-dithiane, 1,4,5-oxadithiephane, and 1,2,5-trithiephane. An experimental design involving authentic Baltic Sea sediments spiked with the target analytes was used to develop an optimized protocol for sample preparation, headspace extraction and analysis that afforded recoveries of up to 60-90%. The optimized method needs no organic solvents, uses only two grams of sediment on a dry weight basis and involves a unique sample presentation whereby sediment is spread uniformly as a thin layer inside the walls of a glass headspace vial. The method showed good linearity for analyte concentrations of 5-200 ng/g dw, good repeatability, and acceptable carry-over. The method's limits of detection for spiked sediment samples ranged from 2.5 to 11 μg/kg dw, with matrix interference being the main limiting factor. The instrumental detection limits were one to two orders of magnitude lower. Full-scan GC-MS analysis enabled the use of automated mass spectral deconvolution for rapid identification of target analytes. Using this approach, analytes could be identified in spiked sediment samples at concentrations down to 13-65 μg/kg dw. On-site validation experiments conducted aboard the research vessel R/V Oceania demonstrated the method's practical applicability, enabling the successful identification of four cyclic sulfur mustard degradation products at concentrations of 15-308μg/kg in sediments immediately after being collected near a wreck at the Bornholm Deep dumpsite in the Baltic Sea. Copyright © 2015 Elsevier B.V. All

  11. A step towards a holistic assessment of soil degradation in Europe: Coupling on-site erosion with sediment transfer and carbon fluxes.

    Science.gov (United States)

    Borrelli, P; Van Oost, K; Meusburger, K; Alewell, C; Lugato, E; Panagos, P

    2018-02-01

    Soil degradation due to erosion is connected to two serious environmental impacts: (i) on-site soil loss and (ii) off-site effects of sediment transfer through the landscape. The potential impact of soil erosion processes on biogeochemical cycles has received increasing attention in the last two decades. Properly designed modelling assumptions on effective soil loss are a key pre-requisite to improve our understanding of the magnitude of nutrients that are mobilized through soil erosion and the resultant effects. The aim of this study is to quantify the potential spatial displacement and transport of soil sediments due to water erosion at European scale. We computed long-term averages of annual soil loss and deposition rates by means of the extensively tested spatially distributed WaTEM/SEDEM model. Our findings indicate that soil loss from Europe in the riverine systems is about 15% of the estimated gross on-site erosion. The estimated sediment yield totals 0.164 ± 0.013Pgyr -1 (which corresponds to 4.62 ± 0.37Mgha -1 yr -1 in the erosion area). The greatest amount of gross on-site erosion as well as soil loss to rivers occurs in the agricultural land (93.5%). By contrast, forestland and other semi-natural vegetation areas experience an overall surplus of sediments which is driven by a re-deposition of sediments eroded from agricultural land. Combining the predicted soil loss rates with the European soil organic carbon (SOC) stock, we estimate a SOC displacement by water erosion of 14.5Tg yr -1 . The SOC potentially transferred to the riverine system equals to 2.2Tgyr -1 (~15%). Integrated sediment delivery-biogeochemical models need to answer the question on how carbon mineralization during detachment and transport might be balanced or even off-set by carbon sequestration due to dynamic replacement and sediment burial. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Study on degrading graphene oxide in wastewater under different conditions for developing an efficient and economical degradation method.

    Science.gov (United States)

    Li, Ting; Zhang, Chao-Zhi; Gu, Chengyue

    2017-12-01

    With popular application of graphene and graphene oxide (GO), they have been discharged into water. Graphene and GO harm organisms. However, an efficient and economical method for removing graphene and GO in wastewater has seldom been reported. Graphene can be oxidized by hydrogen peroxide to give GO; therefore, degradation of graphene oxide is an important step in the procedure of removal of graphene from water. In this paper, GO degradation via photo-Fenton reaction under different conditions was carried out. Experimental results suggested that GO in wastewater can be efficiently and economically degraded into carbon dioxide and H2O when pH value is 3, concentration of H2O2 and FeCl3 are 35 mM and 5 ppm, respectively. Degradation mechanism of GO was suggested based on UV-vis absorption spectra, scanning electron microscopy, X-ray diffraction and liquid chromatography-mass spectra data of degradation intermediates. This paper suggests an efficient and economical degradation way of GO in wastewater.

  13. Highly efficient catalytic reductive degradation of various organic ...

    Indian Academy of Sciences (India)

    by conventional water treatment processes due to their complex aromatic structures, hydrophilic nature and high stability against light, temperature, water, chem- icals, etc.1,2 In this view, degradation of organic dye molecules in waste water has gained paramount atten- tion.1,3 Till date, several techniques such as physical.

  14. Efficiency of rice straw lignocelluloses degradability by Aspergillus ...

    African Journals Online (AJOL)

    In addition, the solid state fermentation significantly (P < 0.01) reduced the concentrations of NDF, ADF, cellulose and hemicellulose in the rice straw by 19.96, 13.8, 16.32 and 32.87%, respectively. The high degradation of the hemicellulose was reflected by the high activity of xylanase enzyme, which hydrolyses xylan in ...

  15. A highly efficient degradation mechanism of methyl orange using Fe-based metallic glass powders.

    Science.gov (United States)

    Xie, Shenghui; Huang, Ping; Kruzic, Jamie J; Zeng, Xierong; Qian, Haixia

    2016-02-23

    A new Fe-based metallic glass with composition Fe76B12Si9Y3 (at. %) is found to have extraordinary degradation efficiency towards methyl orange (MO, C14H14N3SO3) in strong acidic and near neutral environments compared to crystalline zero-valent iron (ZVI) powders and other Fe-based metallic glasses. The influence of temperature (294-328 K) on the degradation reaction rate was measured using ball-milled metallic glass powders revealing a low thermal activation energy barrier of 22.6 kJ/mol. The excellent properties are mainly attributed to the heterogeneous structure consisting of local Fe-rich and Fe-poor atomic clusters, rather than the large specific surface and strong residual stress in the powders. The metallic glass powders can sustain almost unchanged degradation efficiency after 13 cycles at room temperature, while a drop in degradation efficiency with further cycles is attributed to visible surface oxidation. Triple quadrupole mass spectrometry analysis conducted during the reaction was used to elucidate the underlying degradation mechanism. The present findings may provide a new, highly efficient and low cost commercial method for azo dye wastewater treatment.

  16. Efficient enzymatic degradation used as pre-stage treatment for norfloxacin removal by activated sludge.

    Science.gov (United States)

    Zhao, Ruinan; Li, Xiaohong; Hu, Mancheng; Li, Shuni; Zhai, Quanguo; Jiang, Yucheng

    2017-08-01

    Norfloxacin is often found in wastewater treatment plants, groundwater, and even drinking water causing environmental concerns because of its potential undesirable effects on human health or aquatic ecosystems. However, conventional treatments cannot deal with norfloxacin efficiently. This work proposes an efficiently enzymatic degradation of norfloxacin by chloroperoxidase (CPO). 82.18% degradation efficiency of norfloxacin was achieved after 25 min reaction time at pH 5.0 with an enzyme concentration of 1.5 × 10(-9) mol L(-1). HPLC-MS was used to determine the intermediates or final products. The product analysis and determination of the chemical oxygen demand indicated if the enzymatic degradation by CPO was carried out before the usually existing bioremediation techniques (usually activated sludge) in sewage treatment plant, the effluent containing norfloxacin can be decontaminated more efficiently and thoroughly than that only by activated sludge treatment. The eco-toxicity tests using a green algae, Chlorella pyrenoidosa, indicated that the toxicity of degraded products of norfloxacin was lower than the parent norfloxacin molecule. CPO-catalyzed degradation of norfloxacin is a promising alternative for treating effluent containing norfloxacin.

  17. Preparation of ZnO Photocatalyst for the Efficient and Rapid Photocatalytic Degradation of Azo Dyes

    Science.gov (United States)

    Chen, Xiaoqing; Wu, Zhansheng; Liu, Dandan; Gao, Zhenzhen

    2017-02-01

    Zinc oxide (ZnO) photocatalysts were synthesized by sol-gel method using zinc acetate as precursor for degradation of azo dyes under UV irradiation. The resultant samples were characterized by different techniques, such as XRD, SEM, and EDX. The influence of preparation conditions such as calcination temperature and composite ratio on the degradation of methyl orange (MO) was investigated. ZnO prepared with a composite ratio of 4:1 and calcination temperature of 400 °C exhibited 99.70% removal rate for MO. The effect of operation parameters on the degradation was also studied. Results showed that the removal rate of azo dyes increased with the increased dosage of catalyst and decreased initial concentration of azo dyes and the acidic condition is favorable for degradation. Furthermore, the kinetics and scavengers of the reactive species during the degradation were also investigated. It was found that the degradation of azo dyes fitted the first-order kinetics and superoxide ions were the main species. The proposed photocatalyst can efficiently and rapidly degrade azo dyes; thus, this economical and environment-friendly photocatalyst can be applied to the treatment of wastewater contaminated with synthetic dyes.

  18. Rapid and efficient degradation of bisphenol A by chloroperoxidase from Caldariomyces fumago: product analysis and ecotoxicity evaluation of the degraded solution.

    Science.gov (United States)

    Dong, Xiaobo; Li, Haiyun; Jiang, Yucheng; Hu, Mancheng; Li, Shuni; Zhai, Quanguo

    2016-09-01

    To degrade enzymatically bisphenol A (BPA) that causes serious environmental concerns and is difficult to be degraded by chemical or physical methods. BPA (150 mg l(-1)) was completely degraded by chloroperoxidase (CPO)/H2O2 within 7 min at room temperature, atmospheric pressure with the enzyme at 6 μg CPO ml(-1). The degradation products were identified by HPLC-MS, which suggested involvement of multiple steps. Enzymatic treatment followed by existing bioremediation technologies (activated sludge) enhanced removal of COD from 9 to 54 %. Using an ecotoxicity evaluation with Chlorella pyrenoidosa, the degradation products had a lower toxicity than BPA. BPA can be degraded rapidly and efficiently under mild conditions with chloroperoxidase at 6 μg ml(-1). The degradation products had a lower toxicity than BPA.

  19. Controlled Defects of Zinc Oxide Nanorods for Efficient Visible Light Photocatalytic Degradation of Phenol

    Directory of Open Access Journals (Sweden)

    Jamal Al-Sabahi

    2016-03-01

    Full Text Available Environmental pollution from human and industrial activities has received much attention as it adversely affects human health and bio-diversity. In this work we report efficient visible light photocatalytic degradation of phenol using supported zinc oxide (ZnO nanorods and explore the role of surface defects in ZnO on the visible light photocatalytic activity. ZnO nanorods were synthesized on glass substrates using a microwave-assisted hydrothermal process, while the surface defect states were controlled by annealing the nanorods at various temperatures and were characterized by photoluminescence and X-ray photoelectron spectroscopy. High performance liquid chromatography (HPLC was used for the evaluation of phenol photocatalytic degradation. ZnO nanorods with high surface defects exhibited maximum visible light photocatalytic activity, showing 50% degradation of 10 ppm phenol aqueous solution within 2.5 h, with a degradation rate almost four times higher than that of nanorods with lower surface defects. The mineralization process of phenol during degradation was also investigated, and it showed the evolution of different photocatalytic byproducts, such as benzoquinone, catechol, resorcinol and carboxylic acids, at different stages. The results from this study suggest that the presence of surface defects in ZnO nanorods is crucial for its efficient visible light photocatalytic activity, which is otherwise only active in the ultraviolet region.

  20. Controlled Defects of Zinc Oxide Nanorods for Efficient Visible Light Photocatalytic Degradation of Phenol

    Science.gov (United States)

    Al-Sabahi, Jamal; Bora, Tanujjal; Al-Abri, Mohammed; Dutta, Joydeep

    2016-01-01

    Environmental pollution from human and industrial activities has received much attention as it adversely affects human health and bio-diversity. In this work we report efficient visible light photocatalytic degradation of phenol using supported zinc oxide (ZnO) nanorods and explore the role of surface defects in ZnO on the visible light photocatalytic activity. ZnO nanorods were synthesized on glass substrates using a microwave-assisted hydrothermal process, while the surface defect states were controlled by annealing the nanorods at various temperatures and were characterized by photoluminescence and X-ray photoelectron spectroscopy. High performance liquid chromatography (HPLC) was used for the evaluation of phenol photocatalytic degradation. ZnO nanorods with high surface defects exhibited maximum visible light photocatalytic activity, showing 50% degradation of 10 ppm phenol aqueous solution within 2.5 h, with a degradation rate almost four times higher than that of nanorods with lower surface defects. The mineralization process of phenol during degradation was also investigated, and it showed the evolution of different photocatalytic byproducts, such as benzoquinone, catechol, resorcinol and carboxylic acids, at different stages. The results from this study suggest that the presence of surface defects in ZnO nanorods is crucial for its efficient visible light photocatalytic activity, which is otherwise only active in the ultraviolet region. PMID:28773363

  1. Photo-degradation of high efficiency fullerene-free polymer solar cells.

    Science.gov (United States)

    Upama, Mushfika Baishakhi; Wright, Matthew; Mahmud, Md Arafat; Elumalai, Naveen Kumar; Mahboubi Soufiani, Arman; Wang, Dian; Xu, Cheng; Uddin, Ashraf

    2017-12-07

    Polymer solar cells are a promising technology for the commercialization of low cost, large scale organic solar cells. With the evolution of high efficiency (>13%) non-fullerene polymer solar cells, the stability of the cells has become a crucial parameter to be considered. Among the several degradation mechanisms of polymer solar cells, burn-in photo-degradation is relatively less studied. Herein, we present the first systematic study of photo-degradation of novel PBDB-T:ITIC fullerene-free polymer solar cells. The thermally treated and as-prepared PBDB-T:ITIC solar cells were exposed to continuous 1 sun illumination for 5 hours. The aged devices exhibited rapid losses in the short-circuit current density and fill factor. The severe short-circuit current and fill factor burn in losses were attributed to trap mediated charge recombination, as evidenced by an increase in Urbach energy for aged devices.

  2. Mechanochemical transformation of an organic ligand on mineral surfaces: The efficiency of birnessite in catechol degradation

    Energy Technology Data Exchange (ETDEWEB)

    Di Leo, Paola, E-mail: pdileo@imaa.cnr.it [Consiglio Nazionale delle Ricerche - Istituto di Metodologie per l' Analisi Ambientale, C.da S. Loja, Zona Industriale, 85050 Tito Scalo (PZ) (Italy); Pizzigallo, Maria Donata Rosa [Dipartimento di Biologia e Chimica Agroforestale e Ambientale, Universita di Bari Aldo Moro, Via Amendola 165/a, 70126 Bari (Italy); Ancona, Valeria [Consiglio Nazionale delle Ricerche - Istituto di Ricerca sulle Acque, Via F. De Blasio 5, 70132 Bari (Italy); Di Benedetto, Francesco [Dipartimento di Chimica, Universita di Firenze, Via della Lastruccia, 3, 50019 Sesto Fiorentino (Italy); Mesto, Ernesto; Schingaro, Emanuela; Ventruti, Gennaro [Dipartimento di Scienze della Terra e Geoambientali, Universita di Bari Aldo Moro, Via Orabona, 4, 70125 Bari (Italy)

    2012-01-30

    Graphical abstract: . The efficiency of mechanochemical treatments in degrading CAT molecules in presence of the highly reactive phyllomanganate birnessite, and without using organic solvents, has been demonstrated in the present study. Integrating information from different techniques on solid let it possible to get a comprehensive picture of the most reliable reaction mechanism of degradation of CAT molecules onto KBi surfaces, thus allowing the individuation of specific sites in the synthesized oxides on which catechol molecules were preferentially adsorbed, and thus degraded. The degradation mechanism mainly occurs via a redox reaction. It implies the formation of a surface bidentate inner-sphere complex between the phenolic group of the organic molecules and the Mn(IV) from the birnessite structure. Structural changes occur on the MnO{sub 6} layers of birnessite as due to the mechanically induced surface reactions: reduction of Mn(IV), consequent formation of Mn(III) and new vacancies, and free Mn{sup 2+} ions production. The extent of the mechanochemical degradation of CAT onto birnessite surfaces is higher. This is a consequence of the two phenolic groups of catechol that easily reacts. Highlights: Black-Right-Pointing-Pointer A basic insight at molecular scale of the mechanically induced transformations of CAT onto birnessite is obtained. Black-Right-Pointing-Pointer The abiotic degradative mechanisms of CAT onto birnessite is provided. Black-Right-Pointing-Pointer The mechanically induced degradation of CAT mainly occurs via a redox reaction. Black-Right-Pointing-Pointer Mechanochemistry improves the efficiency of birnessite to degrade CAT. Black-Right-Pointing-Pointer The mechanochemical technique offer potentials in remediating contaminated sites. - Abstract: The aim of this work is to investigate the efficiency of the phyllomanganate birnessite in degrading catechol after mechanochemical treatments. A synthesized birnessite and the organic molecule were

  3. Efficient heterogeneous and environmentally friendly degradation of nerve agents on a tungsten-based POM

    Energy Technology Data Exchange (ETDEWEB)

    Mizrahi, Dana M., E-mail: danami@iibr.gov.il [Department of Organic Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100 (Israel); Saphier, Sigal; Columbus, Ishay [Department of Organic Chemistry, Israel Institute for Biological Research, P.O. Box 19, Ness Ziona 74100 (Israel)

    2010-07-15

    Common (chemical warfare agent) CWA decontaminants exhibit harsh and corrosive characteristics, and are harmful to the environment. In the course of our quest for active sorbents as efficient decontaminants, Keggin-type polyoxometalate (POM) (NH{sub 4}){sub 3}PW{sub 12}O{sub 40} was tested for oxidative degradation of CWAs. Although oxidation did not take place, sarin (GB) and VX were smoothly decontaminated to non-toxic products within 1 and 10 days, respectively. Degradation was carried out directly on the powder, eliminating the need for solvents. Mustard gas (HD), whose degradation is highly dependent on oxidation, was not decontaminated by this POM. Solid state MAS NMR ({sup 31}P and {sup 13}C) was utilized both for POM characterization and for decontamination studies monitoring.

  4. Relationship between phenol degradation efficiency and microbial community structure in an anaerobic SBR.

    Science.gov (United States)

    Rosenkranz, F; Cabrol, L; Carballa, M; Donoso-Bravo, A; Cruz, L; Ruiz-Filippi, G; Chamy, R; Lema, J M

    2013-11-01

    Phenol is a common wastewater contaminant from various industrial processes, including petrochemical refineries and chemical compounds production. Due to its toxicity to microbial activity, it can affect the efficiency of biological wastewater treatment processes. In this study, the efficiency of an Anaerobic Sequencing Batch Reactor (ASBR) fed with increasing phenol concentrations (from 120 to 1200 mg L(-1)) was assessed and the relationship between phenol degradation capacity and the microbial community structure was evaluated. Up to a feeding concentration of 800 mg L(-1), the initial degradation rate steadily increased with phenol concentration (up to 180 mg L(-1) d(-1)) and the elimination capacity remained relatively constant around 27 mg phenol removed∙gVSS(-1) d(-1). Operation at higher concentrations (1200 mg L(-1)) resulted in a still efficient but slower process: the elimination capacity and the initial degradation rate decreased to, respectively, 11 mg phenol removed∙gVSS(-1) d(-1) and 154 mg L(-1) d(-1). As revealed by Denaturing Gradient Gel Electrophoresis (DGGE) analysis, the increase of phenol concentration induced level-dependent structural modifications of the community composition which suggest an adaptation process. The increase of phenol concentration from 120 to 800 mg L(-1) had little effect on the community structure, while it involved drastic structural changes when increasing from 800 to 1200 mg L(-1), including a strong community structure shift, suggesting the specialization of the community through the emergence and selection of most adapted phylotypes. The thresholds of structural and functional disturbances were similar, suggesting the correlation of degradation performance and community structure. The Canonical Correspondence Analysis (CCA) confirmed that the ASBR functional performance was essentially driven by specific community traits. Under the highest feeding concentration, the most abundant ribotype probably involved in

  5. Phenol-degrading anode biofilm with high coulombic efficiency in graphite electrodes microbial fuel cell.

    Science.gov (United States)

    Zhang, Dongdong; Li, Zhiling; Zhang, Chunfang; Zhou, Xue; Xiao, Zhixing; Awata, Takanori; Katayama, Arata

    2017-03-01

    A microbial fuel cell (MFC), with graphite electrodes as both the anode and cathode, was operated with a soil-free anaerobic consortium for phenol degradation. This phenol-degrading MFC showed high efficiency with a current density of 120 mA/m2 and a coulombic efficiency of 22.7%, despite the lack of a platinum catalyst cathode and inoculation of sediment/soil. Removal of planktonic bacteria by renewing the anaerobic medium did not decrease the performance, suggesting that the phenol-degrading MFC was not maintained by the planktonic bacteria but by the microorganisms in the anode biofilm. Cyclic voltammetry analysis of the anode biofilm showed distinct oxidation and reduction peaks. Analysis of the microbial community structure of the anode biofilm and the planktonic bacteria based on 16S rRNA gene sequences suggested that Geobacter sp. was the phenol degrader in the anode biofilm and was responsible for current generation. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  6. Electroplating sludge derived zinc-ferrite catalyst for the efficient photo-Fenton degradation of dye.

    Science.gov (United States)

    Cao, Zhenbang; Zhang, Jia; Zhou, Jizhi; Ruan, Xiuxiu; Chen, Dan; Liu, Jianyong; Liu, Qiang; Qian, Guangren

    2017-05-15

    A zinc-dominant ferrite catalyst for efficient degradation of organic dye was prepared by the calcination of electroplating sludge (ES). Characterizations indicated that zinc ferrite (ZnFe2O4) coexisted with Fe2O3 structure was the predominant phase in the calcined electroplating sludge (CES). CES displayed a high decolorization ratio (88.3%) of methylene blue (MB) in the presence of H2O2 combined with UV irradiation. The high efficiency could be ascribed to the photocatalytic process induced by ZnFe2O4 and the photo-Fenton dye degradation by ferrous content, and a small amount of Al and Mg in the sludge might also contribute to the catalysis. Moreover, the degradation capability of dye by CES was supported by the synthetic ZnFe2O4 with different Zn to Fe molar ratio (n(Zn): n(Fe)), as 84.81%-86.83% of dye was removed with n(Zn): n(Fe) ranged from 1:0.5 to 1:3. All synthetic ferrite samples in the simulation achieved adjacent equilibrium decolorization ratio, the flexible proportioning of divalent metal ions (M2+) to trivalent metal ions (M3+) applied in the synthesis indicated that the catalyst has a high availability. Therefore, an efficacious catalyst for the degradation of dye can potentially be derived from heavy metal-containing ES, it's a novel approach for the reutilization of ES. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Isolation and identification of efficient Egyptian malathion-degrading bacterial isolates.

    Science.gov (United States)

    Hamouda, S A; Marzouk, M A; Abbassy, M A; Abd-El-Haleem, D A; Shamseldin, Abdelaal

    2015-03-01

    Bacterial isolates degrading malathion were isolated from the soil and agricultural waste water due to their ability to grow on minimal salt media amended with malathion as a sole carbon source. Efficiencies of native Egyptian bacterial malathion-degrading isolates were investigated and the study generated nine highly effective malathion-degrading bacterial strains among 40. Strains were identified by partial sequencing of 16S rDNA analysis. Comparative analysis of 16S rDNA sequences revealed that these bacteria are similar with the genus Acinetobacter and Bacillus spp. and RFLP based PCR of 16S rDNA gave four different RFLP patterns among strains with enzyme HinfI while with enzyme HaeI they gave two RFLP profiles. The degradation rate of malathion in liquid culture was estimated using gas chromatography. Bacterial strains could degrade more than 90% of the initial malathion concentration (1000 ppm) within 4 days. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Controlled Defects of Zinc Oxide Nanorods for Efficient Visible Light Photocatalytic Degradation of Phenol

    OpenAIRE

    Jamal Al-Sabahi; Tanujjal Bora; Mohammed Al-Abri; Joydeep Dutta

    2016-01-01

    Environmental pollution from human and industrial activities has received much attention as it adversely affects human health and bio-diversity. In this work we report efficient visible light photocatalytic degradation of phenol using supported zinc oxide (ZnO) nanorods and explore the role of surface defects in ZnO on the visible light photocatalytic activity. ZnO nanorods were synthesized on glass substrates using a microwave-assisted hydrothermal process, while the surface defect states we...

  9. Efficient degradation of trichloroethylene in water using persulfate activated by reduced graphene oxide-iron nanocomposite.

    Science.gov (United States)

    Ahmad, Ayyaz; Gu, Xiaogang; Li, Li; Lv, Shuguang; Xu, Yisheng; Guo, Xuhong

    2015-11-01

    Graphene oxide (GO) and nano-sized zero-valent iron-reduced graphene oxide (nZVI-rGO) composite were prepared. The GO and nZVI-rGO composite were characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR), energy-dispersive spectroscopy (EDS), and Raman spectroscopy. The size of nZVI was about 6 nm as observed by TEM. The system of nZVI-rGO and persulfate (PS) was used for the degradation of trichloroethylene (TCE) in water, and showed 26.5% more efficiency as compared to nZVI/PS system. The different parameters were studied to determine the efficiency of nZVI-rGO to activate the PS system for the TCE degradation. By increasing the PS amount, TCE removal was also improved while no obvious effect was observed by varying the catalyst loading. Degradation was decreased as the TCE initial concentration was increased from 20 to 100 mg/L. Moreover, when initial solution pH was increased, efficiency deteriorated to 80%. Bicarbonate showed more negative effect on TCE removal among the solution matrix. To better understand the effects of radical species in the system, the scavenger tests were performed. The •SO4(-) and •O2(-) were predominant species responsible for TCE removal. The nZVI-rGO-activated PS process shows potential applications in remediation of highly toxic organic contaminants such as TCE present in the groundwater. Graphical abstract Persulfate activated by reduced graphene oxide and nano-sized zero-valent iron composite can be used for efficient degradation of trichloroethylene (TCE) in water.

  10. Ag-ligand modified tungstovandates and their efficient catalysis degradation properties for methylene blue

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Ran; Zhang, Huixia; Liu, Yunping; Wang, Xiaoxiao; Han, Zhangang, E-mail: hanzg116@126.com

    2017-02-15

    Two polytungstovandates [Ag(mbpy){sub 2}][Ag{sub 2}(mbpy){sub 3}][VW{sub 5}O{sub 19}]·H{sub 2}O (1) and [Ag(mbpy)]{sub 2}[Ag(mbpy){sub 2}]{sub 4}[VW{sub 12}O{sub 40}] (2) (mbpy =4,4′-dimethyl-2,2′-bipyridyl), had been hydrothermally synthesized and characterized by IR, TG, and single-crystal X-ray diffraction techniques. Single-crystal structural analysis revealed that the polyanionic clusters in two compounds are different: Lindqvist-type in 1 and α-Keggin-type in 2, respectively, while the cationic moieties in them are Ag-mbpy units. The experiments showed that this kind of hybrid crystal materials possesses more efficiently catalytic performance for the degradation of organic dye methylene blue (MB) in water solution under the UV irradiation. The significant degradation rate of MB can reach 89.9%, 94.9% by crystals 1 and 2 (40 mg) in the course of about 5 min. - Graphical abstract: Two Ag-ligand modified polytungstovandates had been synthesized and characterized, which were active in the catalytic degradation of organic dye methylene blue under the UV irradiation. - Highlights: • Two Ag-ligand modified tungstovandates were synthesized and characterized. • Weak interactions play important roles in constructing crystal frameworks. • Compounds are active to catalyze the degradation of methylene blue.

  11. Cellulose Surface Degradation by a Lytic Polysaccharide Monooxygenase and Its Effect on Cellulase Hydrolytic Efficiency*

    Science.gov (United States)

    Eibinger, Manuel; Ganner, Thomas; Bubner, Patricia; Rošker, Stephanie; Kracher, Daniel; Haltrich, Dietmar; Ludwig, Roland; Plank, Harald; Nidetzky, Bernd

    2014-01-01

    Lytic polysaccharide monooxygenase (LPMO) represents a unique principle of oxidative degradation of recalcitrant insoluble polysaccharides. Used in combination with hydrolytic enzymes, LPMO appears to constitute a significant factor of the efficiency of enzymatic biomass depolymerization. LPMO activity on different cellulose substrates has been shown from the slow release of oxidized oligosaccharides into solution, but an immediate and direct demonstration of the enzyme action on the cellulose surface is lacking. Specificity of LPMO for degrading ordered crystalline and unordered amorphous cellulose material of the substrate surface is also unknown. We show by fluorescence dye adsorption analyzed with confocal laser scanning microscopy that a LPMO (from Neurospora crassa) introduces carboxyl groups primarily in surface-exposed crystalline areas of the cellulosic substrate. Using time-resolved in situ atomic force microscopy we further demonstrate that cellulose nano-fibrils exposed on the surface are degraded into shorter and thinner insoluble fragments. Also using atomic force microscopy, we show that prior action of LPMO enables cellulases to attack otherwise highly resistant crystalline substrate areas and that it promotes an overall faster and more complete surface degradation. Overall, this study reveals key characteristics of LPMO action on the cellulose surface and suggests the effects of substrate morphology on the synergy between LPMO and hydrolytic enzymes in cellulose depolymerization. PMID:25361767

  12. Efficient degradation of Rhodamine B by using ethylenediamine-CuCl2 complex under alkaline conditions.

    Science.gov (United States)

    Li, Ying; Yi, Zhongzhou; Zhang, Jucheng; Wu, Mingzhu; Liu, Wei; Duan, Pengqing

    2009-11-15

    In this work, we have developed a simple and efficient approach to the degradation of organic dyes using ethylenediamine-CuCl(2) complex as the catalyst under basic conditions. Rhodamine B has been used as model compound and all experiments were carried out at normal atmospheric pressure and temperature (25+/-1 degrees C) under open-wide system. The different pH values from 7.0 to 14.0 and the catalyst recycling were investigated. The results indicated that ethylenediamine-CuCl(2) was an effective catalyst in the degradation of Rhodamine B at pH 7.0-12.0. It would provide a useful insight into the development of new routes in organic wastewater treatment.

  13. Assessment of solar driven TiO2-assisted photocatalysis efficiency on amoxicillin degradation.

    Science.gov (United States)

    Pereira, João H O S; Reis, Ana C; Nunes, Olga C; Borges, Maria T; Vilar, Vítor J P; Boaventura, Rui A R

    2014-01-01

    The objective of this work was to evaluate the efficiency of a solar TiO2-assisted photocatalytic process on amoxicillin (AMX) degradation, an antibiotic widely used in human and veterinary medicine. Firstly, solar photolysis of AMX was compared with solar photocatalysis in a compound parabolic collectors pilot scale photoreactor to assess the amount of accumulated UV energy in the system (Q UV) necessary to remove 20 mg L(-1) AMX from aqueous solution and mineralize the intermediary by-products. Another experiment was also carried out to accurately follow the antibacterial activity against Escherichia coli DSM 1103 and Staphylococcus aureus DSM 1104 and mineralization of AMX by tracing the contents of dissolved organic carbon (DOC), low molecular weight carboxylate anions, and inorganic anions. Finally, the influence of individual inorganic ions on AMX photocatalytic degradation efficiency and the involvement of some reactive oxygen species were also assessed. Photolysis was shown to be completely ineffective, while only 3.1 kJUV L(-1) was sufficient to fully degrade 20 mg L(-1) AMX and remove 61% of initial DOC content in the presence of the photocatalyst and sunlight. In the experiment with an initial AMX concentration of 40 mg L(-1), antibacterial activity of the solution was considerably reduced after elimination of AMX to levels below the respective detection limit. After 11.7 kJUV L(-1), DOC decreased by 71%; 30% of the AMX nitrogen was converted into ammonium and all sulfur compounds were converted into sulfate. A large percentage of the remaining DOC was in the form of low molecular weight carboxylic acids. Presence of phosphate ions promoted the removal of AMX from solution, while no sizeable effects on the kinetics were found for other inorganic ions. Although the AMX degradation was mainly attributed to hydroxyl radicals, singlet oxygen also plays an important role in AMX self-photosensitization under UV/visible solar light.

  14. ZnO:Ag nanorods as efficient photocatalysts: Sunlight driven photocatalytic degradation of sulforhodamine B

    Science.gov (United States)

    Raji, R.; K. S., Sibi; K. G., Gopchandran

    2018-01-01

    Visible light responsive highly photocatalytic ZnO:Ag nanorods with varying Ag concentration were synthesized via co-precipitation method. X-ray diffraction analysis and high resolution transmission electron microscopy investigations confirmed the hexagonal wurtzite phase for these ZnO:Ag nanorods with preferential growth along the (101) plane. Raman shift and luminescence measurements indicated that the incorporation of Ag influences the lattice vibrational modes; there by causing distortion in lattice, inducing silent vibrational modes and emission behavior by quenching of both the band edge and visible emissions respectively. The photocatalytic performance of these nanorods as catalysts was tested by observing the photodegradation of a representative dye pollutant, viz., sulforhodamine B under sunlight irradiation. Photocatalytic performance was evaluated by determining the rate of reaction kinetics, photodegradation efficiency and mineralization efficiency. A high rate constant of 0.552 min-1, chemical oxygen demand value of 5.8 ppm and a mineralization efficiency of 94% were obtained when ZnO: Ag nanorods with an Ag content of 1.5 at.% were used as catalysts. The observed increase in photocatalytic efficiency with Ag content in ZnO:Ag nanorods is attributed to the electron scavenging action of silver, Schottky barrier between the Ag and ZnO interface and the better utilization of sunlight due to enhanced absorption due to plasmons in the visible region. BET analysis indicated that silver doping causes effective surface area of nanorods to increase, which in turn increases the photocatalytic efficiency. The possible mechanism for degradation of dye under sunlight irradiation is described with a schematic and the photostability of the ZnO:Ag nanorods were also tested through five repetitive cycles. This work suggests that the prepared ZnO:Ag nanorods are excellent reusable photocatalysts for the degradation of toxic organic waste in water, which causes severe

  15. FUV quantum efficiency degradation of cesium iodide photocathodes caused by exposure to thermal atomic oxygen

    Science.gov (United States)

    McPhate, Jason; Anne, Joshi; Bacinski, John; Banks, Bruce; Cates, Carey; Christensen, Paul; Cruden, Brett; Dunham, Larry; Graham, Eric; Hughes, David; Kimble, Randy; Lupie, Olivia; Niedner, Malcolm; Osterman, Steven; Penton, Steven; Proffitt, Charles; Pugel, Diane; Siegmund, Oswald; Wheeler, Thomas

    2011-09-01

    The color dependence of the measured decline of the on-orbit sensitivity of the FUV channel of the HST Cosmic Origins Spectrograph (HST-COS) indicated the principal loss mechanism to be degradation of the cesium iodide (CsI) photocathode of the open-faced FUV detector. A possible cause of this degradation is contamination by atomic oxygen (AO), prompting an investigation of the interaction of AO with CsI. To address this question, opaque CsI photocathodes were deposited on stainless steel substrates employing the same deposition techniques and parameters used for the photocathodes of the HST-COS FUV detector. The as-deposited FUV quantum efficiency of these photocathodes was measured in the 117-174 nm range. Several of the photocathodes were exposed to varying levels of thermalized, atomic oxygen (AO) fluence (produced via an RF plasma). The post AO exposure QE's were measured and the degradation of sensitivity versus wavelength and AO fluence are presented.

  16. Green synthesis of copper nanoparticles for the efficient removal (degradation) of dye from aqueous phase.

    Science.gov (United States)

    Sinha, Tanur; Ahmaruzzaman, M

    2015-12-01

    The present work reports the utilization of a common household waste material (fish scales of Labeo rohita) for the synthesis of copper nanoparticles. The method so developed was found to be green, environment-friendly, and economic. The fish scale extracts were acting as a stabilizing and reducing agents. This method avoids the use of external reducing and stabilizing agents, templates, and solvents. The compositional abundance of gelatin may be envisaged for the effective reductive as well as stabilizing potency. The mechanisms for the formation of nanoparticles have also been presented. The synthesized copper nanoparticles formed were predominantly spherical in nature with an average size of nanoparticles in the range of 25-37 nm. The copper nanoparticles showed characteristic Bragg's reflection planes of fcc which was supported by both selected area electron diffraction and X-ray diffraction pattern and showed surface plasmon resonance at 580 nm. Moreover, the energy dispersive spectroscopy pattern also revealed the presence of only elemental copper in the copper nanoparticles. The prepared nanoparticles were used for the remediation of a carcinogenic and noxious textile dye, Methylene blue, from aqueous solution. Approximately, 96 % degradation of Methylene blue dye was observed within 135 min using copper nanoparticles. The probable mechanism for the degradation of the dye has been presented, and the degraded intermediates have been identified using the liquid chromatography-mass spectroscopy technique. The high efficiency of nanoparticles as photocatalysts has opened a promising application for the removal of hazardous dye from industrial effluents contributing indirectly to environmental cleanup process.

  17. Successful bioaugmentation of an activated sludge reactor with Rhodococcus sp. YYL for efficient tetrahydrofuran degradation.

    Science.gov (United States)

    Yao, Yanlai; Lu, Zhenmei; Zhu, Fengxiang; Min, Hang; Bian, Caimiao

    2013-10-15

    The exchange of tetrahydrofuran (THF)-containing wastewater should significantly affect the performance of an activated sludge system. In this study, the feasibility of using THF-degrading Rhodococcus sp. strain YYL to bioaugment an activated sludge system treating THF wastewater was explored. As indicated by a DGGE analysis, strain YYL alone could not dominate the system, with the concentration of mixed liquor suspended solids (MLSS) decreasing to nearly half of the initial concentration after 45 d, and the microbial diversity was found to be significantly reduced. However, after the reactor was augmented with the mixed culture of strain YYL and two bacilli initially coexisting in the enriched isolation source, strain YYL quickly became dominant in the system and was incorporated into the activated sludge. The concentration of MLSS increased from 2.1g/L to 7.3g/L in 20 d, and the efficiency of THF removal from the system was remarkably improved. After the successful bioaugmentation, more than 95% of THF was completely removed from the wastewater when 20mM THF was continuously loaded into the system. In conclusion, our research first demonstrates that bioaugmentation of activated sludge system for THF degradation is feasible but that successful bioaugmentation should utilize a THF-degrading mixed culture as the inoculum, in which the two bacilli might help strain YYL colonize in activated sludge by co-aggregation. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Treatment of municipal wastewater in full-scale on-site sand filter reduces BOD efficiently but does not reach requirements for nitrogen and phosphorus removal.

    Science.gov (United States)

    Laaksonen, Petteri; Sinkkonen, Aki; Zaitsev, Gennadi; Mäkinen, Esa; Grönroos, Timo; Romantschuk, Martin

    2017-04-01

    A traditional sand filter for treatment of household wastewater was constructed in the fall of 2012 at Biolinja 12, Turku, Finland. Construction work was led and monitored by an authorized wastewater treatment consultant. The filter was placed on a field bordered by open ditches from all sides in order to collect excess rain and snowmelt waters. The filter was constructed and insulated from the environment so that all outflowing water was accounted for. Untreated, mainly municipal, wastewater from Varissuo suburb was pumped from a sewer separately via three septic tanks (volume = 1 m(3) each) into the filters. Normally, wastewater was distributed to ground filters automatically according to pre-programmed schedule. Initially, the daily flow was 1200 L day(-1) to reflect the average organic load of a household of five persons (load: ca 237 g day(-1) BOD; 73 g day(-1) total N; and 10.4 g day(-1) total P). Later in the test, the flow rate was decreased first to 900 and then to 600 L day(-1) to better reflect the average volume produced by five persons. Volumes of inlet wastewater as well as treated water were monitored by magnetic flow meters. Samples were withdrawn from the inlet water, from the water entering the filters after the third septic tank, and from the outflowing water. After an initial adaption time, the reductions in BOD and chemical oxygen demand were constantly between 92 and 98%, showing that the biological degradation process in the filters functioned optimally and clearly comply with the national and EU standards. The reduction in total nitrogen and total phosphorus, however, reached required levels only during the first months of testing, apparently when buildup of microbial biomass was still ongoing. After this initial period of 3 months showing satisfactory reduction levels, the reduction of total nitrogen varied between 5 and 25% and total phosphorus mostly between 50 and 65%. Nitrification was efficient in the filter, but as

  19. Charge collection efficiency degradation induced by MeV ions in semiconductor devices: Model and experiment

    Energy Technology Data Exchange (ETDEWEB)

    Vittone, E., E-mail: ettore.vittone@unito.it [Department of Physics, NIS Research Centre and CNISM, University of Torino, via P. Giuria 1, 10125 Torino (Italy); Pastuovic, Z. [Centre for Accelerator Science (ANSTO), Locked bag 2001, Kirrawee DC, NSW 2234 (Australia); Breese, M.B.H. [Centre for Ion Beam Applications (CIBA), Department of Physics, National University of Singapore, Singapore 117542 (Singapore); Garcia Lopez, J. [Centro Nacional de Aceleradores (CNA), Sevilla University, J. Andalucia, CSIC, Av. Thomas A. Edison 7, 41092 Sevilla (Spain); Jaksic, M. [Department for Experimental Physics, Ruder Boškovic Institute (RBI), P.O. Box 180, 10002 Zagreb (Croatia); Raisanen, J. [Department of Physics, University of Helsinki, Helsinki 00014 (Finland); Siegele, R. [Centre for Accelerator Science (ANSTO), Locked bag 2001, Kirrawee DC, NSW 2234 (Australia); Simon, A. [International Atomic Energy Agency (IAEA), Vienna International Centre, P.O. Box 100, 1400 Vienna (Austria); Institute of Nuclear Research of the Hungarian Academy of Sciences (ATOMKI), Debrecen (Hungary); Vizkelethy, G. [Sandia National Laboratories (SNL), PO Box 5800, Albuquerque, NM (United States)

    2016-04-01

    Highlights: • We study the electronic degradation of semiconductors induced by ion irradiation. • The experimental protocol is based on MeV ion microbeam irradiation. • The radiation induced damage is measured by IBIC. • The general model fits the experimental data in the low level damage regime. • Key parameters relevant to the intrinsic radiation hardness are extracted. - Abstract: This paper investigates both theoretically and experimentally the charge collection efficiency (CCE) degradation in silicon diodes induced by energetic ions. Ion Beam Induced Charge (IBIC) measurements carried out on n- and p-type silicon diodes which were previously irradiated with MeV He ions show evidence that the CCE degradation does not only depend on the mass, energy and fluence of the damaging ion, but also depends on the ion probe species and on the polarization state of the device. A general one-dimensional model is derived, which accounts for the ion-induced defect distribution, the ionization profile of the probing ion and the charge induction mechanism. Using the ionizing and non-ionizing energy loss profiles resulting from simulations based on the binary collision approximation and on the electrostatic/transport parameters of the diode under study as input, the model is able to accurately reproduce the experimental CCE degradation curves without introducing any phenomenological additional term or formula. Although limited to low level of damage, the model is quite general, including the displacement damage approach as a special case and can be applied to any semiconductor device. It provides a method to measure the capture coefficients of the radiation induced recombination centres. They can be considered indexes, which can contribute to assessing the relative radiation hardness of semiconductor materials.

  20. Highly Efficient Photocatalysts and Continuous-Flow Photocatalytic Reactors for Degradation of Organic Pollutants in Wastewater.

    Science.gov (United States)

    Chang, Sujie; Yang, Xiaoqiu; Sang, Yuanhua; Liu, Hong

    2016-09-06

    One of the most important applications for photocatalysis is engineered water treatment that photodegrades organic pollutants in wastewater at low cost. To overcome the low efficiency of batch degradation methods, continuous-flow photocatalytic reactors have been proposed and have become the most promising method for mass water treatment. However, most commercial semiconductor photocatalysts are granular nanoparticles with low activity and a narrow active light wavelength band; this creates difficulties for direct use in continuous-flow photocatalytic reactors. Therefore, a high-performance photodegradation photocatalyst with proper morphology or structure is key for continuous photocatalytic degradation. Moreover, a well-designed photocatalytic device is another important component for continuous-flow photocatalysis and determines the efficiency of photocatalysis in practical water treatment. This review describes the basic design principles and synthesis of photocatalysts with excellent performance and special morphologies suitable for a filtering photocatalysis process. Certain promising continuous photodegradation reactors are also categorized and summarized. Additionally, selected scientific and technical problems that must be urgently solved are suggested. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Highly efficient electro-oxidation catalyst under ultra-low voltage for degradation of aspirin.

    Science.gov (United States)

    Kang, Xiaolei; Sun, Wei; Cao, Limei; Yang, Ji

    2017-11-01

    A novel cryptomelane-Ir (cry-Ir) electrode is prepared for Ir to enter into the cryptomelane (named as cry-Mn) structure and used for aspirin degradation. This catalyst can efficiently reduce the Ir usage from 85 to 34%. Also, the onset potential of cry-Ir is about 1.40 V and the over potential is about 0.34 V at 10 mA cm -2 , indicating that cry-Ir has an excellent oxygen evolution reaction (OER) activity to produce oxidizing species and can decrease electrolytic voltage during the electro-oxidation process. So, the electrical efficiency per log order (EE/O) for cry-Ir electrode is only 5% of PbO 2 electrode, which is the best electrode for organic degradation. Also, cry-Ir has large tunnel size which favors insertion of aspirin molecule into cry-Ir structure and enhances the contact between reactive intermediates and the contaminant. Using cry-Ir as anode, 100% aspirin removal and 55% chemical oxygen demand (COD) removal could be obtained at 4 V. We also compare cry-Ir electrode with IrO 2 and find that IrO 2 anode can only eliminate 20% aspirin under the same condition. As a result, cry-Ir is a promising anode material for organic pollutant degradation. Graphical abstract Aspirin removal after 4h under different voltages. Aspirin removal on IrO 2 /Ti-f and cry-Ir/Ti-f after 4h.

  2. Efficient activation of peroxymonosulfate by magnetic Mn-MGO for degradation of bisphenol A

    Energy Technology Data Exchange (ETDEWEB)

    Du, Jiangkun [School of Environmental Studies, China University of Geosciences, Wuhan 430074 (China); Bao, Jianguo, E-mail: bjianguo@cug.edu.cn [School of Environmental Studies, China University of Geosciences, Wuhan 430074 (China); Liu, Ying; Ling, Haibo; Zheng, Han [School of Environmental Studies, China University of Geosciences, Wuhan 430074 (China); Kim, Sang Hoon, E-mail: kim_sh@kist.re.kr [Center for Materials Architecturing, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Dionysiou, Dionysios D., E-mail: dionysios.d.dionysiou@uc.edu [Environmental Engineering and Science Program, Department of Biomedical, Chemical and Environmental Engineering, 705 Engineering Research Center, University of Cincinnati, Cincinnati, OH 45221-0012 (United States)

    2016-12-15

    Highlights: Manganese catalyst was immobilized on Fe{sub 3}O{sub 4}/graphene hybrids to facilitate magnetic separation. Magnetic manganese catalyst exhibited high efficacy and long-term stability for catalytic PMS activation. The minerlization efficiency and the biotoxicity of BPA byproducts were evaluated. The degradation pathways of BPA and the possible activation mechanism of PMS were proposed. - Abstract: A heterogeneous manganese/magnetite/graphene oxide (Mn-MGO) hybrid catalyst was fabricated through the reduction of KMnO{sub 4} by ethylene glycol in the presence of magnetite/GO (MGO) particles. The Mn-MGO catalyst exhibited high efficacy and long-term stability in activating peroxymonosulfate (PMS) to generate sulfate radicals for the removal of bisphenol A (BPA) from water. The results of the batch experiments indicated that an increase in the catalyst dose and solution pH could enhance BPA degradation in the coupled Mn-MGO/PMS system. Regardless of the initial pH, the solution pH significantly dropped after the reaction, which was caused by catalytic PMS activation. The production of sulfate radicals and hydroxyl radicals was validated through radical quenching and electron paramagnetic resonances (EPR) tests. BPA degradation pathways were proposed on the basis of LC-MS and GC-MS analyses. Finally, a possible mechanism of catalytic PMS activation was proposed that involved electron transfer from MnO or Mn{sub 2}O{sub 3} to PMS with the generation of sulfate radicals, protons and MnO{sub 2}, as well as the simultaneous reduction of MnO{sub 2} by PMS.

  3. Efficient peroxydisulfate activation process not relying on sulfate radical generation for water pollutant degradation

    KAUST Repository

    Zhang, Tao

    2014-05-20

    Peroxydisulfate (PDS) is an appealing oxidant for contaminated groundwater and toxic industrial wastewaters. Activation of PDS is necessary for application because of its low reactivity. Present activation processes always generate sulfate radicals as actual oxidants which unselectively oxidize organics and halide anions reducing oxidation capacity of PDS and producing toxic halogenated products. Here we report that copper oxide (CuO) can efficiently activate PDS under mild conditions without producing sulfate radicals. The PDS/CuO coupled process is most efficient at neutral pH for decomposing a model compound, 2,4-dichlorophenol (2,4-DCP). In a continuous-flow reaction with an empty-bed contact time of 0.55 min, over 90% of 2,4-DCP (initially 20 μM) and 90% of adsorbable organic chlorine (AOCl) can be removed at the PDS/2,4-DCP molar ratio of 1 and 4, respectively. Based on kinetic study and surface characterization, PDS is proposed to be first activated by CuO through outer-sphere interaction, the rate-limiting step, followed by a rapid reaction with 2,4-DCP present in the solution. In the presence of ubiquitous chloride ions in groundwater/industrial wastewater, the PDS/CuO oxidation shows significant advantages over sulfate radical oxidation by achieving much higher 2,4-DCP degradation capacity and avoiding the formation of highly chlorinated degradation products. This work provides a new way of PDS activation for contaminant removal. © 2014 American Chemical Society.

  4. Efficient treatment of perfluorohexanoic acid by nanofiltration followed by electrochemical degradation of the NF concentrate.

    Science.gov (United States)

    Soriano, Álvaro; Gorri, Daniel; Urtiaga, Ane

    2017-04-01

    The present study was aimed at the development of a strategy for removing and degrading perfluorohexanoic acid (PFHxA) from industrial process waters at concentrations in the range 60-200 mg L(-1). The treatment train consisted of nanofiltration (NF) separation followed by electrochemical degradation of the NF concentrate. Using a laboratory-scale system and working in the total recirculation mode, the DowFilm NF270 membrane provided PFHxA rejections that varied in the range 96.6-99.4% as the operating pressure was increased from 2.5 to 20 bar. The NF operation in concentration mode enabled a volume reduction factor of 5 and increased the PFHxA concentration in the retentate to 870 mg L(-1). Results showed that the increase in PFHxA concentration and the presence of calcium sulfate salts did not induce irreversible membrane fouling. The NF retentate was treated in a commercial undivided electrochemical cell provided with two parallel flow-by compartments separated by bipolar boron doped diamond (BDD) electrode, BDD counter anode, and counter cathode. Current densities ranging from 20 to 100 A m(-2) were examined. The electrochemical degradation rate of PFHxA reached 98% and was accompanied by its efficient mineralization, as the reduction of total organic carbon was higher than 95%. Energy consumption, which was 15.2 kWh m(-3) of treated NF concentrate, was minimized by selecting operation at 50 A m(-2). While most of the previous research on the treatment of perfluoroalkyl substances (PFASs) focused on the removal of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), these compounds have been phased out by chemical manufacturers. Our findings are relevant for the treatment of PFHxA, which appears to be one of the present alternatives to long-chain PFASs thanks to its lower bioaccumulative potential than PFOA and PFOS. However, PFHxA also behaves as a persistent pollutant. Moreover, our results highlight the potential of combining

  5. A Study of Efficiency of Zero-valent Iron Nanoparticles in Degradation of Trichlorethylene from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Samaneh Dehghan

    2016-12-01

    mg/l, and contact time= 86 min. The results of kinetic studies revealed that TCE degradation by nZVI follows first-order kinetic model. Conclusion: It is conclude that zero-valent iron nanoparticles have a good efficiency in the degradation of TCE. On the other hand, separation of these nanoparticles is simple due to its magnetism properties, which can improve the use of these nanoparticles. 

  6. Efficient photocatalytic degradation of perfluorooctanoic acid by a wide band gap p-block metal oxyhydroxide InOOH

    Science.gov (United States)

    Xu, Jingjing; Wu, Miaomiao; Yang, Jingwen; Wang, Zhengmei; Chen, Mindong; Teng, Fei

    2017-09-01

    In this work, we prepared a new wide band gap semiconductor, p-block metal oxyhydroxide InOOH, which exhibits efficient activity for perfluorooctanoic acid (PFOA) degradation under mild conditions and UV light irradiation. The apparent rate constant for PFOA degradation by InOOH is 27.6 times higher than that for P25 titania. Results show that ionized PFOA (C7F15COO-) can be adsorbed much more efficiently on the surface of InOOH than P25. Then, the adsorbed C7F15COO- can be decomposed directly by photo-generated holes to form C7F15COOrad radicals. This process is the key step for the photocalytic degradation of PFOA. Major degradation intermediates, fluoride ions and perfluorinated carboxylic acids (PFCAs) with shorter chain lengths were detected during PFOA degradation. A possible pathway for photocatalytic degradation of PFOA is proposed based on the experimental results. Therefore, this studies indicates a potential new material and method for the efficient treatment of PFCA pollutants under mild conditions.

  7. Ultra Efficient CHHP Using a High Temperature Fuel Cell to Provide On-Site Process Reducing Gas, Clean Power, and Heat

    Energy Technology Data Exchange (ETDEWEB)

    Jahnke, Fred C. [Fuelcell Energy, Inc., Danbury, CT (United States)

    2015-06-30

    FuelCell Energy and ACuPowder investigated and demonstrated the use of waste anode exhaust gas from a high temperature fuel cell for replacing the reducing gas in a metal processing furnace. Currently companies purchase high pressure or liquefied gases for the reducing gas which requires substantial energy in production, compression/liquefaction, and transportation, all of which is eliminated by on-site use of anode exhaust gas as reducing gas. We performed research on the impact of the gas composition on product quality and then demonstrated at FuelCell Energy’s manufacturing facility in Torrington, Connecticut. This demonstration project continues to operate even though the research program is completed as it provides substantial benefits to the manufacturing facility by supplying power, heat, and hydrogen.

  8. Nanostructured CoP: An efficient catalyst for degradation of organic pollutants by activating peroxymonosulfate

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Rui; Liu, Chao; Li, Jiansheng, E-mail: lijsh@mail.njust.edu.cn; Wang, Jing; Hu, Xingru; Sun, Xiuyun; Shen, Jinyou; Han, Weiqing; Wang, Lianjun

    2017-05-05

    Highlights: • The CoP/PMS system was first presented for decomposition of pollutants. • CoP exhibited dramatic catalytic activity. • Broadened pH range and favorable anti-interference of anions were achieved. • A possible mechanism for activation of PMS by CoP was proposed. - Abstract: A new catalyst system of CoP/peroxymonosulfate (PMS) is presented, which achieved significant improvement in catalytic activity. Nanostructured CoP, obtained by a simple solid-state reaction, exhibited dramatic catalytic activity with 97.2% degradation of orange II of 100 ppm within 4 min. Moreover, the high efficiency could be reached for other phenolic pollutants, i.e., phenol and 4-chlorophenol. The reaction rate is much higher than the most reported catalysts. Effect of parameters on catalytic activity of the catalyst was studied in detail. Notably, initial pH of the solution had a slight negative effect on the catalytic performance over the pH range 4.07–10.92, suggesting that CoP has the great adaptability of pH. CoP/PMS demonstrated excellent anti-interference performance toward anions (Cl{sup −}, NO{sub 3}{sup −}, and HCO{sub 3}{sup −}). In addition, the pathway of degradation of orange II is proposed by analyzing its intermediates. Based on the XPS spectra of CoP, the identification of the reactive species (·OH and SO{sub 4}·{sup −}) by electron paramagnetic resonance (EPR) analysis and quenching tests, a possible mechanism for activation of PMS by CoP was proposed. Considering the dramatic catalytic activity, a wide range of pH catalyst suited, CoP is believed to provide robust support for the promising industrial application of AOPs.

  9. Preparation of an Efficient Ratiometric Fluorescent Nanoprobe (m-CDs@[Ru(bpy)3]2+) for Visual and Specific Detection of Hypochlorite on Site and in Living Cells.

    Science.gov (United States)

    Zhan, Yuanjin; Luo, Fang; Guo, Longhua; Qiu, Bin; Lin, Yuhong; Li, Juan; Chen, Guonan; Lin, Zhenyu

    2017-11-02

    Hypochlorite (ClO-) is one of the most important reactive oxygen species (ROS), which plays an important role in sustaining human innate immunity during microbial invasion. Moreover, ClO- is a powerful oxidizer for water treatment. The safety of drinking water is closely related to its content. Herein, m-phenylenediamine (mPD) is used as a precursor to prepare carbon dots (named m-CDs) with highly fluorescent quantum yield (31.58% in water), and our investigation shows that the strong fluorescent emission of m-CDs can be effectively quenched by ClO-. Based on these findings, we developed a novel fluorescent nanoprobe (m-CDs) for highly selective detection of ClO-. The linear range was from 0.05 to 7 μM (R2 = 0.998), and the limit of detection (S/N = 3) was as low as 0.012 μM. Moreover, a portable agarose hydrogel solid matrix-based ratiometric fluorescent nanoprobe (m-CDs@[Ru(bpy)3]2+) sensor was subsequently developed for visual on-site detection of ClO- with the naked eyes under a UV lamp, suggesting its potential in practical application with low cost and excellent performance in water quality monitoring. Additionally, intracellular detection of exogenous ClO- was demonstrated via ratiometric imaging microscopy.

  10. A bifunctionalized dye-sensitized TiO(2) film for efficient degradation of methyl orange under visible light irradiation.

    Science.gov (United States)

    Wu, Quanping; Zhao, Jun; Qin, Guohui; Wang, Xuezheng; Tong, Xinli; Xue, Song

    2012-01-01

    A new bifunctionalized TiO(2) film containing a dye-sensitized region and a degradation region was described. A similar structure of dye-sensitized solar cell (DSSC) was fabricated in the dye-sensitized region to accomplish separation of electrons from positive charges, and separation of dye from pollutants to avoid dye decomposition. The bifunctionalized TiO(2) film electrode and anode electrode can degrade methyl orange (MO) in reactors A and B, respectively. The degradation efficiency was enhanced remarkably by an external electrical potential. The decolorization of MO reaches as high as 95% after 2 h visible light irradiation at an external potential of 0.5 V along with a loss of 41% total organic carbon (TOC). The possible reason for the improvement of degradation by external DC potential was discussed. Effects of pH and inorganic salts on the decolorization are present.

  11. The efficiency of turn-over processes in degraded peat as investigated under continuous flow conditions

    Science.gov (United States)

    Kleimeier, Christian; Karsten, Ulf; Janssen, Manon; Lennartz, Bernd

    2013-04-01

    Nitrate removal from run-off from agricultural land is in general required to reach a "good chemical status" of surface and groundwater bodies according to the European Water Framework Directive. Removing nitrates via heterotrophic denitrification is highly effective but requires stable anoxic environmental conditions as well as available organic carbon as an electron donator. Constructed wetlands, established on peat soils, through which the nitrate-loaded water is routed, may provide denitrification favorable conditions. A long-term flow experiment (mesocosm) was conducted employing a laboratory container set-up filled with decomposed peat aiming at quantifying the nitrate removal efficiency at various nitrate influx rates. The redox potential was measured at different depths to determine the spatial distribution of denitrificating zones. This new methodological approach allows the observation of biological nitrate turn over without interrupting the adjusted flow rate. We investigated the hydraulic properties and derived transport parameters for the mesocosm by analyzing experimental data from tracer tests. The obtained bromide breakthrough curves (BTC) were subjected to model analysis using the CXTFIT routine of the STANMOD software package. It could be demonstrated that the degraded peat has a dual porosity structure with roughly 40% of the pore water not participating in convective flow and transport processes. Further, the first flushing of mineralized nitrate upon rewetting and onset of flux may compromise any positive clean-up and nitrate removal effects occurring during long-term operation of peat wetlands. The development of the spatial sequence of bacterial cultures is characterized by the redox potential. It is dominated by the available substrates that serve as electron acceptors in bacterial respiration and occurs in a thermodynamically determined top-down order. The zonal development of the nitrate-consuming bacteria was observed and used to describe

  12. High-Capacity and Photoregenerable Composite Material for Efficient Adsorption and Degradation of Phenanthrene in Water.

    Science.gov (United States)

    Liu, Wen; Cai, Zhengqing; Zhao, Xiao; Wang, Ting; Li, Fan; Zhao, Dongye

    2016-10-18

    We report a novel composite material, referred to as activated charcoal supported titanate nanotubes (TNTs@AC), for highly efficient adsorption and photodegradation of a representative polycyclic aromatic hydrocarbon (PAH), phenanthrene. TNTs@AC was prepared through a one-step hydrothermal method, and is composed of an activated charcoal core and a shell of carbon-coated titanate nanotubes. TNTs@AC offered a maximum Langmuir adsorption capacity of 12.1 mg/g for phenanthrene (a model PAH), which is ∼11 times higher than the parent activated charcoal. Phenanthrene was rapidly concentrated onto TNTs@AC, and subsequently completely photodegraded under UV light within 2 h. The photoregenerated TNTs@AC can then be reused for another adsorption-photodegradation cycle without significant capacity or activity loss. TNTs@AC performed well over a wide range of pH, ionic strength, and dissolved organic matter. Mechanistically, the enhanced adsorption capacity is attributed to the formation of carbon-coated ink-bottle pores of the titanate nanotubes, which are conducive to capillary condensation; in addition, the modified microcarbon facilitates transfer of excited electrons, thereby inhibiting recombination of the electron-hole pairs, resulting in high photocatalytic activity. The combined high adsorption capacity, photocatalytic activity, and regenerability/reusability merit TNTs@AC a very attractive material for concentrating and degrading a host of micropollutants in the environment.

  13. Viral RNA Degradation and Diffusion Act as a Bottleneck for the Influenza A Virus Infection Efficiency.

    Directory of Open Access Journals (Sweden)

    Max Schelker

    2016-10-01

    Full Text Available After endocytic uptake, influenza viruses transit early endosomal compartments and eventually reach late endosomes. There, the viral glycoprotein hemagglutinin (HA triggers fusion between endosomal and viral membrane, a critical step that leads to release of the viral segmented genome destined to reach the cell nucleus. Endosomal maturation is a complex process involving acidification of the endosomal lumen as well as endosome motility along microtubules. While the pH drop is clearly critical for the conformational change and membrane fusion activity of HA, the effect of intracellular transport dynamics on the progress of infection remains largely unclear. In this study, we developed a comprehensive mathematical model accounting for the first steps of influenza virus infection. We calibrated our model with experimental data and challenged its predictions using recombinant viruses with altered pH sensitivity of HA. We identified the time point of virus-endosome fusion and thereby the diffusion distance of the released viral genome to the nucleus as a critical bottleneck for efficient virus infection. Further, we concluded and supported experimentally that the viral RNA is subjected to cytosolic degradation strongly limiting the probability of a successful genome import into the nucleus.

  14. Daily and alternate-day supplementation of urea or biuret to ruminants consuming low-quality forage: II. Effects on site of digestion and microbial efficiency in steers.

    Science.gov (United States)

    Currier, T A; Bohnert, D W; Falck, S J; Schauer, C S; Bartle, S J

    2004-05-01

    Five steers (491 +/- 21 kg BW) were used in an incomplete 5 x 4 Latin square with four 24-d periods to determine the influence of supplemental non-protein N (NPN) source and supplementation frequency (SF) on nutrient intake and site of digestion in steers consuming low-quality grass straw (4% CP). Treatments (TRT) included an unsupplemented control and a urea- or biuret-containing supplement placed directly into the rumen daily (D) or every other day (2D) at 0700. The NPN treatments were formulated to provide 90% of the estimated degradable intake protein requirement. Daily TRT were supplemented CP at 0.04% of BW/d, whereas the 2D TRT were supplemented at 0.08% of BW every other day. Therefore, all supplemented TRT received the same quantity of supplemental CP over a 2-d period. Forage OM intake was not affected (P > 0.05) by NPN supplementation, NPN source, or SF; however, total OM and N intake were increased (P biuret compared with urea (P biuret than for urea. Apparent total-tract N digestibility was increased with NPN supplementation (P biuret can be used effectively as a supplemental N source by steers consuming low-quality forage.

  15. Highly efficient degradation of thidiazuron with Ag/AgCl- activated carbon composites under LED light irradiation.

    Science.gov (United States)

    Yang, Yisi; Zhang, Yan; Dong, Mingguang; Yan, Ting; Zhang, Maosheng; Zeng, Qingru

    2017-08-05

    Thidiazuron (TDZ; 1-phenyl-3-(1,2,3-thiadiazol-5-yl)urea) is one of the most widely used defoliant and easy to dissolve in surface water. Risk associated with the pesticide is not clearly defined, so it is important to remove/degrade TDZ with an efficient and environment friendly technology. Here, we investigated the use of Ag/AgCl-activated carbon (Ag/AgCl-AC) composites in photocatalytic degradation of TDZ under LED light. By the synergic effect of Ag/AgCl and AC, the optimum Ag/carbon weight ratio of 2:1 exhibited superior visible-light photocatalytic activity, the highest removal efficiency was close to 91% in pH 7 matrix. Different types of Ag/AgCl-AC composites were tested, all showed much faster photodegradation kinetics than bare Ag/AgCl in 210min. The degradation products as identified by HPLC-MS revealed that the hydroxylation by hydroxyl radicals and that of oxidation by superoxide radicals as well as holes were the two main pathways for TDZ degradation. Results revealed that the adsorption concentrated TDZ molecules and the photocatalytically generated radicals rapidly degradated TDZ, the two contributions functioned together for removal of the pollutant from water. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Highly efficient degradation of thidiazuron with Ag/AgCl- activated carbon composites under LED light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yisi [College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128 (China); Hubei Key Laboratory for Processing and Application of Catalytic Materials, Huanggang Normal University, Huanggang 438000 (China); College of Chemical Engineering, Huanggang Normal University, Huanggang 438000 (China); Zhang, Yan [Hubei Key Laboratory for Processing and Application of Catalytic Materials, Huanggang Normal University, Huanggang 438000 (China); College of Chemical Engineering, Huanggang Normal University, Huanggang 438000 (China); Dong, Mingguang; Yan, Ting; Zhang, Maosheng [College of Chemical Engineering, Huanggang Normal University, Huanggang 438000 (China); Zeng, Qingru, E-mail: 40083763@qq.com [College of Bioscience and Biotechnology, Hunan Agricultural University, Changsha 410128 (China)

    2017-08-05

    Highlights: • Photocatalytic degradation of thidiazuron was performed in a neutral water matrix. • This was carried out in the presence of Ag/AgCl-activated carbon composites and LED light. • The pH effect and the dominant active species were explored. • Degradation products and pathways in water were studied for the first time. - Abstract: Thidiazuron (TDZ; 1-phenyl-3-(1,2,3-thiadiazol-5-yl)urea) is one of the most widely used defoliant and easy to dissolve in surface water. Risk associated with the pesticide is not clearly defined, so it is important to remove/degrade TDZ with an efficient and environment friendly technology. Here, we investigated the use of Ag/AgCl-activated carbon (Ag/AgCl–AC) composites in photocatalytic degradation of TDZ under LED light. By the synergic effect of Ag/AgCl and AC, the optimum Ag/carbon weight ratio of 2:1 exhibited superior visible-light photocatalytic activity, the highest removal efficiency was close to 91% in pH 7 matrix. Different types of Ag/AgCl–AC composites were tested, all showed much faster photodegradation kinetics than bare Ag/AgCl in 210 min. The degradation products as identified by HPLC–MS revealed that the hydroxylation by hydroxyl radicals and that of oxidation by superoxide radicals as well as holes were the two main pathways for TDZ degradation. Results revealed that the adsorption concentrated TDZ molecules and the photocatalytically generated radicals rapidly degradated TDZ, the two contributions functioned together for removal of the pollutant from water.

  17. Modeling charge collection efficiency degradation in partially depleted GaAs photodiodes using the 1- and 2-carrier Hecht equations

    Science.gov (United States)

    Auden, E. C.; Vizkelethy, G.; Serkland, D. K.; Bossert, D. J.; Doyle, B. L.

    2017-05-01

    The Hecht equation can be used to model the nonlinear degradation of charge collection efficiency (CCE) in response to radiation-induced displacement damage in both fully and partially depleted GaAs photodiodes. CCE degradation is measured for laser-generated photocurrent as a function of fluence and bias in Al0.3Ga0.7As/GaAs/Al0.25Ga0.75As p-i-n photodiodes which have been irradiated with 12 MeV C and 7.5 MeV Si ions. CCE is observed to degrade more rapidly with fluence in partially depleted photodiodes than in fully depleted photodiodes. When the intrinsic GaAs layer is fully depleted, the 2-carrier Hecht equation describes CCE degradation as photogenerated electrons and holes recombine at defect sites created by radiation damage in the depletion region. If the GaAs layer is partially depleted, CCE degradation is more appropriately modeled as the sum of the 2-carrier Hecht equation applied to electrons and holes generated within the depletion region and the 1-carrier Hecht equation applied to minority carriers that diffuse from the field-free (non-depleted) region into the depletion region. Enhanced CCE degradation is attributed to holes that recombine within the field-free region of the partially depleted intrinsic GaAs layer before they can diffuse into the depletion region.

  18. Modeling charge collection efficiency degradation in partially depleted GaAs photodiodes using the 1- and 2-carrier Hecht equations

    Energy Technology Data Exchange (ETDEWEB)

    Auden, E.C., E-mail: eauden@sandia.gov; Vizkelethy, G.; Serkland, D.K.; Bossert, D.J.; Doyle, B.L.

    2017-05-15

    The Hecht equation can be used to model the nonlinear degradation of charge collection efficiency (CCE) in response to radiation-induced displacement damage in both fully and partially depleted GaAs photodiodes. CCE degradation is measured for laser-generated photocurrent as a function of fluence and bias in Al{sub 0.3}Ga{sub 0.7}As/GaAs/Al{sub 0.25}Ga{sub 0.75}As p-i-n photodiodes which have been irradiated with 12 MeV C and 7.5 MeV Si ions. CCE is observed to degrade more rapidly with fluence in partially depleted photodiodes than in fully depleted photodiodes. When the intrinsic GaAs layer is fully depleted, the 2-carrier Hecht equation describes CCE degradation as photogenerated electrons and holes recombine at defect sites created by radiation damage in the depletion region. If the GaAs layer is partially depleted, CCE degradation is more appropriately modeled as the sum of the 2-carrier Hecht equation applied to electrons and holes generated within the depletion region and the 1-carrier Hecht equation applied to minority carriers that diffuse from the field-free (non-depleted) region into the depletion region. Enhanced CCE degradation is attributed to holes that recombine within the field-free region of the partially depleted intrinsic GaAs layer before they can diffuse into the depletion region.

  19. Isolation and characterization of a high-efficiency erythromycin A-degrading Ochrobactrum sp. strain.

    Science.gov (United States)

    Zhang, Weiwei; Qiu, Lina; Gong, Aijun; Yuan, Xiaotao

    2017-01-30

    In this work, Erythromycin A(EA)- degrading bacteria was isolated from the contaminated soil obtained from a pharmaceutical factory in China. The isolate designated as strain WX-J1 was identified as Ochrobactrum sp. by sequence analysis of its 16S rDNA gene. It can grow in a medium containing EA as the sole source of carbon and its optimal growth pH and temperature were 6.5 and 32°C, respectively. Under these conditions, when the initial Erythromycin A concentration was 100mg·L-1, 97% of Erythromycin A has been degraded. HPLC-MS analyses indicated that Erythromycin A degradation produced intermediates contained the following three substances: 3-depyranosyloxy erythromycin A, 7,12-dyhydroxy-6-deoxyerythronolide B, 6-deoxyerythronolide B and propionaldehyde. Since Erythromycin A-degrading Ochrobactrum sp. strain rapidly degraded Erythromycin A, this strain might be useful for bioremediation purposes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Efficient separation of oxidized cello-oligosaccharides generated by cellulose degrading lytic polysaccharide monooxygenases.

    Science.gov (United States)

    Westereng, Bjørge; Agger, Jane Wittrup; Horn, Svein J; Vaaje-Kolstad, Gustav; Aachmann, Finn L; Stenstrøm, Yngve H; Eijsink, Vincent G H

    2013-01-04

    We present an evaluation of HPLC-based analytical tools for the simultaneous analysis of native and oxidized cello-oligosaccharides, which are products of enzymatic cellulose degradation. Whereas cello-oligosaccharides arise from cellulose depolymerization by glycoside hydrolases, oxidized cello-oligosaccharides are produced by cellobiose dehydrogenase and the recently identified copper dependent lytic polysaccharide monooxygenases (LPMOs) currently classified as CBM33 and GH61. The latter enzymes are wide-spread and expected to play crucial roles in further development of efficient enzyme technology for biomass conversion. Three HPLC approaches with well documented performance in the field of oligosaccharide analysis have been investigated: high-performance anion-exchange chromatography (HPAEC), hydrophilic interaction chromatography (HILIC) and porous graphitized carbon liquid chromatography (PGC-LC). HPAEC with pulsed amperometric detection (PAD) was superior for analysis of oxidized oligosaccharides, combining the best separation with superior sensitivity for oligosaccharide species with a degree of polymerization (DP) ranging from 1 to 10. Furthermore, the HPAEC method can be optimized for operation in a high-throughput manner (run time 10 min). Both PGC-LC and HILIC allow reasonable run times (41 and 25 min, respectively), with acceptable separation, but suffer from poor sensitivity compared to HPAEC-PAD. On the other hand, PGC-LC and HILIC benefit from being fully compatible with online mass spectrometry. Using an LC-MS setup, these methods will deliver much better sensitivity than what can be obtained with conventional detectors such as ultraviolet-, charged aerosol-, or evaporative light scattering and may reach sensitivities similar to or even better than what is obtained in HPAEC-PAD. Pure oxidized cello-oligosaccharide standards, ranging from DP2 to DP5, were obtained by semi-preparative PGC and characterized by MS and NMR analysis. Copyright © 2012

  1. A concept for planning and management of on-site and centralised municipal wastewater treatment systems, a case study in Bangkok, Thailand. I: pollutant discharge indicators and pollutant removal efficiency functions.

    Science.gov (United States)

    Tsuzuki, Yoshiaki; Koottatep, Thammarat; Sinsupan, Thitiphon; Jiawkok, Supattra; Wongburana, Chira; Wattanachira, Suraphong; Sarathai, Yuttachai

    2013-01-01

    The concept of pollution load indicators for planning and management of the mixture conditions of centralised and on-site wastewater treatment systems has not been discussed in detail so far. In this paper, pollutant discharge (load) indicators and pollutant removal efficiencies were quantitatively analysed to develop a part of a strategy for planning and management of municipal wastewater treatment systems (WWTSs) under the mixture conditions in Bangkok, Thailand, as a case study. Pollutant discharge indicators of on-site WWTSs were estimated based on the relevant literature. Three kinds of pollutant removal efficiency function at centralised wastewater treatment plants (CWWTPs) were empirically developed for biological oxygen demand, chemical oxygen demand, total nitrogen, total phosphorus, total coliforms and faecal coliforms based on the existing CWWTP management data. These results will be integrated into the scenario-based analysis in the second paper in the series. The results will be base datasets, and the concept and estimation methods can be applied for wastewater treatment planning and management in other areas.

  2. Efficiency of the intestinal bacteria in the degradation of the toxic pesticide, chlorpyrifos.

    Science.gov (United States)

    Harishankar, M K; Sasikala, C; Ramya, M

    2013-04-01

    Chlorpyrifos (CP) is the most commonly used pesticide throughout the world. Its widespread use in agriculture and its potential toxicity to humans from ingestion of CP contaminated food have raised concerns about its risk to health. Human intestinal microflora has the ability to degrade pesticides, but the exact mechanisms involved and the metabolite end-products formed are not well understood. The primary objective of this work was to analyse the in vitro degradation of CP by five model intestinal bacteria namely Lactobacillus lactis, L. fermentum, L. plantarum, Escherichia coli and Enterococcus faecalis. Plate assay results revealed that L. lactis, E. coli and L. fermentum could grow with high concentrations of CP (>1,400 μg/mL), whereas E. faecalis and L. plantarum could grow with concentrations as low as 400 and 100 μg/mL, respectively. The best three CP degraders were therefore used in further experiments. The degradation of CP-induced organophosphorous phosphatase (OPP) production and that OPP concentration were higher in the supernatant (extracellular) rather than inside the cells by factor of up to 28. L. fermentum degraded 70 % CP with 3,5,6-trichloro-2-pyridinol (TCP) detected as the end product. L.lactis degraded up to 61 % CP with chlorpyrifos oxon detected as the end product, whereas E.coli degraded a lesser concentration (16 %) to chlorpyrifos-oxon and diethylphosphate.

  3. Degradation and recovery of the external quantum efficiency of organic photovoltaic structure

    Energy Technology Data Exchange (ETDEWEB)

    Lazarev, V. V., E-mail: lbf@ns.crys.ras.ru; Blinov, L. M.; Yudin, S. G.; Palto, S. P. [Russian Academy of Sciences, Shubnikov Institute of Crystallography, Federal Scientific Research Centre “Crystallography and Photonics” (Russian Federation)

    2017-03-15

    The photosensitivity of a mixed composition of donor CuPc and acceptor C{sub 60}, its degradation in time (for 16 months), and partial recovery (issues that were out of consideration previously) have been investigated. The sample is a simple nanostructure without encapsulation (quartz–SnO{sub 2}–CuPc:C{sub 60}–Al), the degradation of which is easier to analyze. It is shown that the process under study involves two mechanisms: slow (because of the decrease in the carrier lifetime) and relatively fast (because of the decrease in the internal field) degradations of the sample photosensitivity.

  4. Introducing saccharic acid as an efficient iron chelate to enhance photo-Fenton degradation of organic contaminants.

    Science.gov (United States)

    Subramanian, Gokulakrishnan; Madras, Giridhar

    2016-11-01

    The identification of iron chelates that can enhance photo-Fenton degradation is of great interest in the field of advanced oxidation process. Saccharic acid (SA) is a polyhydroxy carboxylic acid and completely non-toxic. Importantly, it can effectively bind Fe(III) as well as induce photoreduction of Fe(III). Despite having these interesting properties, the effect of SA on photo-Fenton degradation has not been studied. Herein, we demonstrate the first assessment of SA as an iron chelate in photo-Fenton process using methylene blue (MB) as a model organic contaminant. Our results demonstrate that SA has the ability to (i) enhance the photo-Fenton degradation of MB by about 11 times at pH 4.5 (ii) intensify photochemical reduction of Fe(III) to Fe(II) by about 17 times and (iii) accelerate the rate of consumption of H2O2 in photo-Fenton process by about 5 times (iv) increase the TOC reduction by about 2 times and (v) improve the photo-Fenton degradation of MB in the presence of a variety of common inorganic ions and organic matter. The influential properties of SA on photo-Fenton degradation is attributed to the efficient photochemical reduction of Fe(III) via LMCT (ligand to metal charge transfer reaction) to Fe(II), which then activated H2O2 to generate OH and accelerated photo-Fenton degradation efficiency. Moreover, the effect of operational parameters such as oxidant: contaminant (H2O2: MB) ratio, catalyst: contaminant (Fe(III)SA: MB) ratio, Fe(III): SA stoichiometry and pH on the degradation of MB by photo-Fenton in the presence of SA is demonstrated. Importantly, SA assisted photo-Fenton caused effective degradation of MB and 4-Chlorophenol under natural sunlight irradiation in natural water matrix. The findings strongly support SA as a deserving iron chelate to enhance photo-Fenton degradation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Catalytic ozonation of oxalate with a cerium supported palladium oxide: An efficient degradation not relying on hydroxyl radical oxidation

    KAUST Repository

    Zhang, Tao

    2011-11-01

    The cerium supported palladium oxide (PdO/CeO 2) at a low palladium loading was found very effective in catalytic ozonation of oxalate, a probe compound that is difficult to be efficiently degraded in water with hydroxyl radical oxidation and one of the major byproducts in ozonation of organic matter. The oxalate was degraded into CO 2 during the catalytic ozonation. The molar ratio of oxalate degraded to ozone consumption increased with increasing catalyst dose and decreasing ozone dosage and pH under the conditions of this study. The maximum molar ratio reached around 1, meaning that the catalyst was highly active and selective for oxalate degradation in water. The catalytic ozonation, which showed relatively stable activity, does not promote hydroxyl radical generation from ozone. Analysis with ATR-FTIR and in situ Raman spectroscopy revealed that 1) oxalate was adsorbed on CeO 2 of the catalyst forming surface complexes, and 2) O 3 was adsorbed on PdO of the catalyst and further decomposed to surface atomic oxygen (*O), surface peroxide (*O 2), and O 2 gas in sequence. The results indicate that the high activity of the catalyst is related to the synergetic function of PdO and CeO 2 in that the surface atomic oxygen readily reacts with the surface cerium-oxalate complex. This kind of catalytic ozonation would be potentially effective for the degradation of polar refractory organic pollutants and hydrophilic natural organic matter. © 2011 American Chemical Society.

  6. Efficient degradation of solid yeast biomass from ethanol industry by Fenton and UV-Fenton processes applying multivariate analysis

    Directory of Open Access Journals (Sweden)

    Geórgia Labuto

    2017-12-01

    Full Text Available Organic agro-industrial residues have been successfully used as biosorbents and promoting new uses from agricultural wastes benefits the economy. However, the allocation of a solid waste biosorbent after the sorption of contaminants has limited their effective application on a large scale as an alternative treatment of water and wastewaters. One solution could be degradation to convert the biosorbent material and adsorbed organic contaminants into environmental friendly compounds suitable for discharge. This study used an experimental design to evaluate the Fenton degradation of yeast biomass (YB from the alcohol industry as a potential biosorbent. The efficiency of degradation was monitored according to the degraded mass (DM and total organic carbon (TOC remaining in the solution. The ANOVA showed an error of 9.7% for the effects and the media of interaction for the employed model for DM. Conducting the experiments with the best-predicted conditions (60 min, 25 g of YB, pH 3, 8,000 mg L-1 H2O2 and 40 mg L-1 Fe2+ with 30 W UV irradiation resulted in a YB reduction of 72  2% with a TOC of 30  2%. This suggests that an advanced oxidative process is an alternative for degradation of a biosorbent after sorption.

  7. Efficient visible light-induced degradation of rhodamine B by W(NxS1?x)2 nanoflowers

    OpenAIRE

    Peitao Liu; Jingyan Zhang; Daqiang Gao; Weichun Ye

    2017-01-01

    Here, W(NxS1?x)2 nanoflowers were fabricated by simple sintering process. Photocatalytic activity results indicated our fabricated N-doped WS2 nanoflowers shown outstanding photoactivity of degradating of rhodamine B with visible light. Which is attributed to the high separation efficiency of photoinduced electron?hole pairs, the broadening of the valence band (VB), and the narrowing of energy band gap. Meanwhile, our work provided a novel method to induce surface sulfur vacancies in crystals...

  8. Highly efficient color-stable deep-blue multilayer PLEDs: preventing PEDOT:PSS-induced interface degradation.

    Science.gov (United States)

    Nau, Sebastian; Schulte, Niels; Winkler, Stefanie; Frisch, Johannes; Vollmer, Antje; Koch, Norbert; Sax, Stefan; List, Emil J W

    2013-08-27

    Highly efficient and stable blue light emission is observed in novel copolymers that are produced from specially designed building blocks. A PEDOT:PSS-induced chemical degradation of the polymer light-emitting diodes (PLEDs) is identified at the interface, and it is found to be accompanied by a shift in the emission color. A method to prevent this highly undesirable interaction is presented. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Efficiency of Photo-Fenton Process in Degradation of 2-Chlorophenol

    Directory of Open Access Journals (Sweden)

    Reza Moradi

    2017-10-01

    Full Text Available Background & Aims of the Study: Phenolic compounds have been extensively used in industries for applications such as petrochemical, oil refineries, papers, plastics, steel, pharmaceuticals, textiles, coal conversion, and so on. Specified amounts of Phenolic compounds are lost in the process of their manufacturing and utilization and often cause environmental pollution problems. So, removal these compounds of industrial wastewaters are necessary. The aim of this paper, is the photo-degradation environmental pollutant 2-Chlorophenol (2-CP using photo-Fenton process which was used a photo reactor for photo-catalytic degradation of 2-CP in aqueous solution. Materials & Methods: This is an experimental study on a laboratory scale. Fe2+ ions as a homogeneous catalyst applied for the degradation of 2-CP in aqueous solution. The study was performed on synthetic wastewaters that contain 2-CP pollutant. The effect of operational parameters such as: pH, initial concentration Fe2+, H2O2 concentration and temperature were studied. The effect of UV irradiation, UV/H2O2 and UV/Fe2+/H2O2 on photo-catalytic degradation of 2-CP were studied. The reaction kinetic was studied. In this paper, optimum conditions were determined for the photo-catalytic degradation of 2-CP using a factor at the time method. Results: The optimal conditions for this reaction were obtained at pH of 6, initial concentration Fe2+ at 20 ppm, H2O2 concentration at 14 ppm and temperature at 45 °C. A first order reaction with rate constant (k=0.0375 min−1 was observed for the photo-catalytic degradation reaction. These experiments demonstrated that UV radiation, Fe2+ ions and H2O2 oxidation process were needed for the effective degradation of 2-CP. Conclusion: The results showed that the photo-Fenton process can be suitable alternative to removal phenolic compounds from wastewaters.

  10. A double-stranded RNA degrading enzyme reduces the efficiency of oral RNA interference in migratory locust.

    Science.gov (United States)

    Song, Huifang; Zhang, Jianqin; Li, Daqi; Cooper, Anastasia M W; Silver, Kristopher; Li, Tao; Liu, Xiaojian; Ma, Enbo; Zhu, Kun Yan; Zhang, Jianzhen

    2017-07-01

    Application of RNA interference (RNAi) for insect pest management is limited by variable efficiency of RNAi in different insect species. In Locusta migratoria, RNAi is highly efficient through injection of dsRNA, but oral delivery of dsRNA is much less effective. Efforts to understand this phenomenon have shown that dsRNA is more rapidly degraded in midgut fluid than in hemolymph due to nuclease enzyme activity. In the present study, we identified and characterized two full-length cDNAs of double-stranded RNA degrading enzymes (dsRNase) from midgut of L. migratoria, which were named LmdsRNase2 and LmdsRNase3. Gene expression analysis revealed that LmdsRNase2 and LmdsRNase3 were predominantly expressed in the midgut, relatively lower expression in gastric caeca, and trace expression in other tested tissues. Incubation of dsRNA in midgut fluid from LmdsRNase3-suppressed larvae or control larvae injected with dsGFP resulted in high levels of degradation; however, dsRNA incubated in midgut fluid from LmdsRNase2-suppressed larvae was more stable, indicating LmdsRNase2 is responsible for dsRNA degradation in the midgut. To verify the biological function of LmdsRNase2 in vivo, nymphs were injected with dsGFP, dsLmdsRNase2 or dsLmdsRNase3 and chitinase 10 (LmCht10) or chitin synthase 1 (LmCHS1) dsRNA were orally delivered. Mortality associated with reporter gene knockdown was observed only in locusts injected with dsLmdsRNase2 (48% and 22%, for dsLmCht10 and dsLmCHS1, respectively), implicating LmdsRNase2 in reducing RNAi efficiency. Furthermore, recombinantly expressed LmdsRNase2 fusion proteins degraded dsRNA rapidly, whereas LmdsRNase3 did not. These results suggest that rapid degradation of dsRNA by dsRNase2 in the midgut is an important factor causing low RNAi efficiency when dsRNA is orally delivered in the locust. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Present on Site

    DEFF Research Database (Denmark)

    Ingemann, Bruno

    Why are exhibitions and museums so important? What can they be used for? Who determines relevance in a transformative process? Transforming exhibitions is not just something you do, it is something that gets better the more you do it. This book looks at the intersection of the visitor or user, who...... gets personal and cultural meaning from their visit and the museum as it appears in the design of the exhibition. It examines on-site communication for intentional and hidden content and messages, and reveals possible relations to the visitor, his or her world and society in general. This investigation...

  12. Efficient degradation of carbamazepine by easily recyclable microscaled CuFeO{sub 2} mediated heterogeneous activation of peroxymonosulfate

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Yaobin, E-mail: yaobinding@mail.scuec.edu.cn [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan 430074 (China); Tang, Hebin [College of Pharmacy, South-Central University for Nationalities, Wuhan 430074 (China); Zhang, Shenghua; Wang, Songbo [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan 430074 (China); Tang, Heqing, E-mail: tangheqing@mail.scuec.edu.cn [Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission and Ministry of Education, College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan 430074 (China)

    2016-11-05

    Highlights: • CuFeO{sub 2} microparticles were prepared by a microwave-assisted hydrothermal method. • CuFeO{sub 2} microparticles efficiently catalyzed the activation of peroxymonosulfate. • Quenching experiments confirmed sulfate radicals as the major reactive radicals. • Carbamazepine was rapidly degraded by micro-CuFeO{sub 2}/peroxymonosulfate. • Feasibility of CuFeO{sub 2}/peroxymonosulfate was tested for treatment of actual water. - Abstract: Microscaled CuFeO{sub 2} particles (micro-CuFeO{sub 2}) were rapidly prepared via a microwave-assisted hydrothermal method and characterized by scanning electron microscopy, X-ray powder diffraction and X-ray photoelectron spectroscopy. It was found that the micro-CuFeO{sub 2} was of pure phase and a rhombohedral structure with size in the range of 2.8 ± 0.6 μm. The micro-CuFeO{sub 2} efficiently catalyzed the activation of peroxymonosulfate (PMS) to generate sulfate radicals (SO{sub 4}·−), causing the fast degradation of carbamazepine (CBZ). The catalytic activity of micro-CuFeO{sub 2} was observed to be 6.9 and 25.3 times that of micro-Cu{sub 2}O and micro-Fe{sub 2}O{sub 3}, respectively. The enhanced activity of micro-CuFeO{sub 2} for the activation of PMS was confirmed to be attributed to synergistic effect of surface bonded Cu(I) and Fe(III). Sulfate radical was the primary radical species responsible for the CBZ degradation. As a microscaled catalyst, micro-CuFeO{sub 2} can be easily recovered by gravity settlement and exhibited improved catalytic stability compared with micro-Cu{sub 2}O during five successive degradation cycles. Oxidative degradation of CBZ by the couple of PMS/CuFeO{sub 2} was effective in the studied actual aqueous environmental systems.

  13. Efficient degradation of tetrabromobisphenol A by synergistic integration of Fe/Ni bimetallic catalysis and microbial acclimation.

    Science.gov (United States)

    Peng, Xingxing; Wang, Zhangna; Huang, Jingfei; Pittendrigh, Barry R; Liu, Shengwei; Jia, Xiaoshan; Wong, Po Keung

    2017-10-01

    This study provides a novel technology for the degradation of tetrabromobisphenol A (TBBPA) via an interaction of Fe redox and a shift of functional microbial community. TBBPA was degraded by integration of synthesized Fe-Ni bimetallic particles and enriched microbial consortium within an aqueous system. This cooperative integration yielded the best TBBPA-degrading capacity (100% removal after treatment for 2 h) and highest TOC-removing efficiency (94.5% removal after treatment for 96 h), as well as the lowest toxicity to Vibrio fischeri (almost 0% growth inhibition during reaction). The synergistic mechanism of integrated system was clarified based on systematical analyses of the degradation processes as well as the shifts in microbial community. Owing to the microbial metabolism and the Fenton-like process of leaked Fe(2+), Fe(3+) and Ni(2+) from Fe-Ni bimetallic catalyst, reactive oxidative species (ROS), including superoxide (O2(-)), hydroxyl radicals (OH) and hydrogen peroxide (H2O2) were produced and evaluated by multiple techniques. Moreover, the quenching experiments indicated that OH was the major ROS leading to TBBPA degradation, rather than H2O2 or O2(-). Based on the analysis of the 12 detected intermediates, three parallel pathways were proposed. It was clearly revealed that reductive and oxidative debromination, hydroxylation, and β-scission simultaneously occurred in the integrated system. Fe non-randomly accelerated the enrichment of TBBPA-degrading microbes (e.g. Pseudomonas sp. and Citrobacter sp., etc.). Above all, this novel technology has great promise for field-applications for remediation of TBBPA-contaminated field. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Preparation of ZnO Photocatalyst for the Efficient and Rapid Photocatalytic Degradation of Azo Dyes

    OpenAIRE

    Chen, Xiaoqing; Wu, Zhansheng; Liu, Dandan; Gao, Zhenzhen

    2017-01-01

    Zinc oxide (ZnO) photocatalysts were synthesized by sol?gel method using zinc acetate as precursor for degradation of azo dyes under UV irradiation. The resultant samples were characterized by different techniques, such as XRD, SEM, and EDX. The influence of preparation conditions such as calcination temperature and composite ratio on the degradation of methyl orange (MO) was investigated. ZnO prepared with a composite ratio of 4:1 and calcination temperature of 400??C exhibited 99.70% remova...

  15. DHA Inhibits Protein Degradation More Efficiently than EPA by Regulating the PPARγ/NFκB Pathway in C2C12 Myotubes

    Directory of Open Access Journals (Sweden)

    Yue Wang

    2013-01-01

    Full Text Available This study was conducted to evaluate the mechanism by which n-3 PUFA regulated the protein degradation in C2C12 myotubes. Compared with the BSA control, EPA at concentrations from 400 to 600 µM decreased total protein degradation (P0.05. Interestingly, EPA and DHA both still decreased the total protein degradation, although PPARγ knockdown attenuated the suppressive effects of EPA and DHA on the total protein degradation (P<0.01. These results revealed that DHA inhibits protein degradation more efficiently than EPA by regulating the PPARγ/NF-κB pathway in C2C12 myotubes.

  16. Efficient photocatalytic degradation of phenol in aqueous solution by SnO{sub 2}:Sb nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Al-Hamdi, Abdullah M., E-mail: Abdullah.Al.Hamdi@lut.fi [Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli (Finland); Chemistry Department, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Sillanpää, Mika [Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli (Finland); Bora, Tanujjal [Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Dutta, Joydeep [Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Functional Materials Division, ICT, KTH Royal Institute of Technology, Isafjordsgatan 22, SE-164 40 KistaStockholm (Sweden)

    2016-05-01

    Highlights: • Sb doped SnO{sub 2} nanoparticles were synthesized using sol–gel process. • Photocatalytic degradation of phenol were studies using SnO{sub 2}:Sb nanoparticles. • Under solar light phenol was degraded within 2 h. • Phenol mineralization and intermediates were investigated by using HPLC. - Abstract: Photodegradation of phenol in the presence of tin dioxide (SnO{sub 2}) nanoparticles under UV light irradiation is known to be an effective photocatalytic process. However, phenol degradation under solar light is less effective due to the large band gap of SnO{sub 2}. In this study antimony (Sb) doped tin dioxide (SnO{sub 2}) nanoparticles were prepared at a low temperature (80 °C) by a sol–gel method and studied for its photocatalytic activity with phenol as a test contaminant. The catalytic degradation of phenol in aqueous media was studied using high performance liquid chromatography and total organic carbon measurements. The change in the concentration of phenol affects the pH of the solution due to the by-products formed during the photo-oxidation of phenol. The photoactivity of SnO{sub 2}:Sb was found to be a maximum for 0.6 wt.% Sb doped SnO{sub 2} nanoparticles with 10 mg L{sup −1} phenol in water. Within 2 h of photodegradation, more than 95% of phenol could be removed under solar light irradiation.

  17. Identification and Characterization of a High Efficiency Aniline Resistance and Degrading Bacterium MC-01.

    Science.gov (United States)

    Yang, Liu; Ying, Chen; Fang, Ni; Zhong, Yao; Zhao-Xiang, Zhong; Yun, Sun

    2017-05-01

    Biodegradation is one of the important methods for the treatment of industrial wastewater containing aniline. In this paper, a degrading bacterium named MC-01, which could survive in high concentration aniline wastewater, was screened from industrial wastewater containing aniline and sludge. MC-01 was preliminarily identified as Ochrobactrum sp. based on the amplified 16S rDNA gene sequence and Biolog system identification. MC-01 was highly resistant to aniline. After 24-h culture under aniline concentration of 6500 mg/L, the amount of bacterium survived still remained 0.05 × 10(6) CFU/mL. Experiments showed that there was no coupling expression between the growth of MC-01 and aniline degradation. The optimum growth conditions in LB culture were pH 6.0, 30 °C of temperature, and 4% of incubation amount, respectively. And the optimum conditions of aniline degradation of MC-01 were pH 7.0, 45 °C of temperature, and 3.0% of salt concentration, respectively. The degradation rate of MC-01 (48 h) in different aniline concentrations (200~1600 mg/L) was stable under the optimum conditions, which could reach more than 75%.

  18. Abnormal strong burn-in degradation of highly efficient polymer solar cells caused by spinodal donor-acceptor demixing.

    Science.gov (United States)

    Li, Ning; Perea, José Darío; Kassar, Thaer; Richter, Moses; Heumueller, Thomas; Matt, Gebhard J; Hou, Yi; Güldal, Nusret S; Chen, Haiwei; Chen, Shi; Langner, Stefan; Berlinghof, Marvin; Unruh, Tobias; Brabec, Christoph J

    2017-02-22

    The performance of organic solar cells is determined by the delicate, meticulously optimized bulk-heterojunction microstructure, which consists of finely mixed and relatively separated donor/acceptor regions. Here we demonstrate an abnormal strong burn-in degradation in highly efficient polymer solar cells caused by spinodal demixing of the donor and acceptor phases, which dramatically reduces charge generation and can be attributed to the inherently low miscibility of both materials. Even though the microstructure can be kinetically tuned for achieving high-performance, the inherently low miscibility of donor and acceptor leads to spontaneous phase separation in the solid state, even at room temperature and in the dark. A theoretical calculation of the molecular parameters and construction of the spinodal phase diagrams highlight molecular incompatibilities between the donor and acceptor as a dominant mechanism for burn-in degradation, which is to date the major short-time loss reducing the performance and stability of organic solar cells.

  19. Selective Degradation of Organic Pollutants Using an Efficient Metal-Free Catalyst Derived from Carbonized Polypyrrole via Peroxymonosulfate Activation.

    Science.gov (United States)

    Hu, Peidong; Su, Hanrui; Chen, Zhenyu; Yu, Chunyang; Li, Qilin; Zhou, Baoxue; Alvarez, Pedro J J; Long, Mingce

    2017-10-03

    Metal-free carbonaceous materials, including nitrogen-doped graphene and carbon nanotubes, are emerging as alternative catalysts for peroxymonosulfate (PMS) activation to avoid drawbacks of conventional transition metal-containing catalysts, such as the leaching of toxic metal ions. However, these novel carbocatalysts face relatively high cost and complex syntheses, and their activation mechanisms have not been well-understood. Herein, we developed a novel nitrogen-doped carbonaceous nanosphere catalyst by carbonization of polypyrrole, which was prepared through a scalable chemical oxidative polymerization. The defective degree of carbon substrate and amount of nitrogen dopants (i.e., graphitic nitrogen) were modulated by the calcination temperature. The product carbonized at 800 °C (CPPy-F-8) exhibited the best catalytic performance for PMS activation, with 97% phenol degradation efficiency in 120 min. The catalytic system was efficient over a wide pH range (2-9), and the reaction of phenol degradation had a relatively low activation energy (18.4 ± 2.7 kJ mol(-1)). The nitrogen-doped carbocatalyst activated PMS through a nonradical pathway. A two-step catalytic mechanism was extrapolated: the catalyst transfers electrons to PMS through active nitrogen species and becomes a metastable state of the catalyst (State I); next, organic substrates are oxidized and degraded by serving as electron donors to reduce State I. The catalytic process was selective toward degradation of various aromatic compounds with different substituents, probably depending on the oxidation state of State I and the ionization potential (IP) of the organics; that is, only those organics with an IP value lower than ca. 9.0 eV can be oxidized in the CPPy-F-8/PMS system.

  20. Molecular Characterization of Lactobacillus plantarum DMDL 9010, a Strain with Efficient Nitrite Degradation Capacity

    OpenAIRE

    Yong-tao Fei; Dong-mei Liu; Tong-hui Luo; Gu Chen; Hui Wu; Li Li; Yi-gang Yu

    2014-01-01

    Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010) was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four oth...

  1. Molecular Characterization of Lactobacillus plantarum DMDL 9010, a Strain with Efficient Nitrite Degradation Capacity

    Science.gov (United States)

    Fei, Yong-tao; Liu, Dong-mei; Luo, Tong-hui; Chen, Gu; Wu, Hui; Li, Li; Yu, Yi-gang

    2014-01-01

    Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010) was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four other Lactobacillus strains, including Lactobacillus casei subsp. rhamnosus 719, Lactobacillus delbrueckii subsp. bulgaricu 1.83, Streptococcus thermophilus 1.204, and lactobacillus plantarum 8140, on MRS medium. Compared to these four Lactobacillus strains, Lactobacillus sp. DMDL 9010 had a significantly higher nitrite degradation capacity (PLactobacillus sp. DMDL 9010 was identified as either Lactobacillus plantarum or Lactobacillus pentosus. To further identify this strain, the flanking regions (922 bp and 806 bp upstream and downstream, respectively) of the L-lactate dehydrogenase 1 (L-ldh1) gene were amplified and sequenced. Lactobacillus sp. DMDL 9010 had 98.92 and 76.98% sequence identity in the upstream region with L. plantarum WCFS1 and L. pentosus IG1, respectively, suggesting that Lactobacillu sp. DMDL 9010 is an L. plantarum strain. It was therefore named L. plantarum DMDL 9010. Our study provides a platform for genetic engineering of L. plantarum DMDL 9010, in order to further improve its nitrite degradation capacity. PMID:25423449

  2. Molecular characterization of Lactobacillus plantarum DMDL 9010, a strain with efficient nitrite degradation capacity.

    Directory of Open Access Journals (Sweden)

    Yong-tao Fei

    Full Text Available Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010 was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four other Lactobacillus strains, including Lactobacillus casei subsp. rhamnosus 719, Lactobacillus delbrueckii subsp. bulgaricu 1.83, Streptococcus thermophilus 1.204, and lactobacillus plantarum 8140, on MRS medium. Compared to these four Lactobacillus strains, Lactobacillus sp. DMDL 9010 had a significantly higher nitrite degradation capacity (P<0.001. Based on 16S rDNA sequencing and sequence comparison, Lactobacillus sp. DMDL 9010 was identified as either Lactobacillus plantarum or Lactobacillus pentosus. To further identify this strain, the flanking regions (922 bp and 806 bp upstream and downstream, respectively of the L-lactate dehydrogenase 1 (L-ldh1 gene were amplified and sequenced. Lactobacillus sp. DMDL 9010 had 98.92 and 76.98% sequence identity in the upstream region with L. plantarum WCFS1 and L. pentosus IG1, respectively, suggesting that Lactobacillu sp. DMDL 9010 is an L. plantarum strain. It was therefore named L. plantarum DMDL 9010. Our study provides a platform for genetic engineering of L. plantarum DMDL 9010, in order to further improve its nitrite degradation capacity.

  3. Molecular characterization of Lactobacillus plantarum DMDL 9010, a strain with efficient nitrite degradation capacity.

    Science.gov (United States)

    Fei, Yong-tao; Liu, Dong-mei; Luo, Tong-hui; Chen, Gu; Wu, Hui; Li, Li; Yu, Yi-gang

    2014-01-01

    Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010) was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four other Lactobacillus strains, including Lactobacillus casei subsp. rhamnosus 719, Lactobacillus delbrueckii subsp. bulgaricu 1.83, Streptococcus thermophilus 1.204, and lactobacillus plantarum 8140, on MRS medium. Compared to these four Lactobacillus strains, Lactobacillus sp. DMDL 9010 had a significantly higher nitrite degradation capacity (PDMDL 9010 was identified as either Lactobacillus plantarum or Lactobacillus pentosus. To further identify this strain, the flanking regions (922 bp and 806 bp upstream and downstream, respectively) of the L-lactate dehydrogenase 1 (L-ldh1) gene were amplified and sequenced. Lactobacillus sp. DMDL 9010 had 98.92 and 76.98% sequence identity in the upstream region with L. plantarum WCFS1 and L. pentosus IG1, respectively, suggesting that Lactobacillu sp. DMDL 9010 is an L. plantarum strain. It was therefore named L. plantarum DMDL 9010. Our study provides a platform for genetic engineering of L. plantarum DMDL 9010, in order to further improve its nitrite degradation capacity.

  4. Supported TiO2 on Borosilicate Glass Plates for Efficient Photocatalytic Degradation of Fenamiphos

    Directory of Open Access Journals (Sweden)

    A. El Yadini

    2014-01-01

    Full Text Available Supported titanium dioxide (TiO2 was investigated for the photodegradation of the insecticide fenamiphos in water. The photocatalyst was immobilised on borosilicate glass plates and the kinetics of degradation were studied in a stirred tank reactor under UV irradiation. Two types of TiO2, for example, Millennium PC500 (100% anatase and Degussa P25 (80% anatase, 20% rutile, were used. Their activities have been based on the rates of insecticide disappearance. Experiments were investigated to evaluate the effect of pH and initial concentrations of fenamiphos as well as catalyst doses on the photocatalytic degradation of fenamiphos. Kinetic parameters were experimentally determined and an apparent first-order kinetic was observed. For photolysis process of fenamiphos, two photoproducts were identified and characterized using high performance liquid chromatography/mass spectrometry (HPLC/MS. The plausible mechanism of photolysis involved is the oxidation of sulfonamide group. In presence of photocatalyst TiO2, photodegradation was observed. Under identical conditions, Degussa P25 shows higher photocatalytic activity in regard to PC500 Millennium and complete degradation was observed after 180 min.

  5. Efficiency of new fungal cellulase systems in boosting enzymatic degradation of barley straw lignocellulose.

    Science.gov (United States)

    Rosgaard, Lisa; Pedersen, Sven; Cherry, Joel R; Harris, Paul; Meyer, Anne S

    2006-01-01

    This study examined the cellulytic effects on steam-pretreated barley straw of cellulose-degrading enzyme systems from the five thermophilic fungi Chaetomium thermophilum, Thielavia terrestris, Thermoascus aurantiacus, Corynascus thermophilus, and Myceliophthora thermophila and from the mesophile Penicillum funiculosum. The catalytic glucose release was compared after treatments with each of the crude enzyme systems when added to a benchmark blend of a commercial cellulase product, Celluclast, derived from Trichoderma reesei and a beta-glucosidase, Novozym 188, from Aspergillus niger. The enzymatic treatments were evaluated in an experimental design template comprising a span of pH (3.5-6.5) and temperature (35-65 degrees C) reaction combinations. The addition to Celluclast + Novozym 188 of low dosages of the crude enzyme systems, corresponding to 10 wt % of the total enzyme protein load, increased the catalytic glucose yields significantly as compared to those obtained with the benchmark Celluclast + Novozyme 188 blend. A comparison of glucose yields obtained on steam-pretreated barley straw and microcrystalline cellulose, Avicel, indicated that the yield improvements were mainly due to the presence of highly active endoglucanase activity/activities in the experimental enzyme preparations. The data demonstrated the feasibility of boosting the widely studied T. reeseicellulase enzyme system with additional enzymatic activity to achieve faster lignocellulose degradation. We conclude that this supplementation strategy appears feasible as a first step in identifying truly promising fungal enzyme sources for fast development of improved, commercially viable, enzyme preparations for lignocellulose degradation.

  6. Degradation efficiency and mechanism of azo dye RR2 by a novel ozone aerated internal micro-electrolysis filter.

    Science.gov (United States)

    Zhang, Xian-Bing; Dong, Wen-Yi; Sun, Fei-Yun; Yang, Wei; Dong, Jiao

    2014-07-15

    A newly designed ozone aerated internal micro-electrolysis filter (OIEF) was developed to investigate its degradation efficiencies and correlated reaction mechanisms of RR2 dye. Complete decolorization and 82% TOC removal efficiency were stably achieved in OIEF process. Based on the comprehensive experimental results, an empirical equation was proposed to illustrate the effects of initial dye concentration and ozone dosage rate on color removal. The results indicated that OIEF process could be operated at wide pH range without significant treatment efficiencies change, while the optimum pH for RR2 dye degradation was 9.0. There were 15, 8 and 6 kinds of identified intermediates during ozonation, IE and OIEF treatment processes, respectively. Less identified intermediates and their lower concentrations in OIEF may attribute to its rather excellent mineralization performance. It was found that ozonation, Fe(2+)/Fe(3+) catalyzed ozonation, the redox reactions of electro-reduction and electro-oxidation are the most important mechanisms in OIEF process. The catalytic effect of Fe(2+)/Fe(3+) would induce mutual conversion between dissolved Fe(2+) and Fe(3+), and then decrease the dissolution rate of ZVI. The excellent treatment performance proved that the OIEF process is one promising technology applied for reactive azo dyes and other refractory wastewater treatment. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Ascorbate-Promoted Surface Iron Cycle for Efficient Heterogeneous Fenton Alachlor Degradation with Hematite Nanocrystals.

    Science.gov (United States)

    Huang, Xiaopeng; Hou, Xiaojing; Jia, Falong; Song, Fahui; Zhao, Jincai; Zhang, Lizhi

    2017-03-15

    This study reports the H2O2 activation with different hematite nanocrystals and ascorbate ions for the herbicide alachlor degradation at pH 5. We found that hematite nanoplates (HNPs) exposed with {001} facets exhibited better catalytic performance than hematite nanocubes (HNCs) exposed with {012} facets, which was attributed to the formation of inner-sphere iron-ascorbate complexes on the hematite facets. The 3-fold undercoordination Fe cations of {001} facet favors the formation of inner-sphere iron-ascorbate complexes, while the 5-fold undercoordination Fe cations of {012} facet has stereo-hindrance effect, disfavoring the complex formation. The surface area normalized alachlor degradation rate constant (23.3 × 10-4 min-1 L m-2) of HNPs-ascorbate Fenton system was about 2.6 times that (9.1 × 10-4 min-1 L m-2) of HNCs-ascorbate counterpart. Meanwhile, the 89.0% of dechlorination and 30.0% of denitrification in the HNPs-ascorbate Fenton system were also significantly higher than those (60.9% and 13.1%) of the HNCs-ascorbate one. More importantly, the reductive dissolution of hematite by ascorbate was strongly coupled with the subsequent H2O2 decomposition by surface bound ferrous ions through surface iron cycle on the hematite facets in the hematite-ascorbate Fenton systems. This coupling could significantly inhibit the conversion of surface bound ferrous ions to dissolved ones, and thus account for the stability of hematite nanocrystals. This work sheds light on the internal relationship between iron geochemical cycling and contaminants degradation, and also inspires us to utilize surface iron cycle of widely existent hematite for environmental remediation.

  8. Efficient visible-light photocatalytic degradation of sulfadiazine sodium with hierarchical Bi₇O₉I₃under solar irradiation.

    Science.gov (United States)

    Xu, MengMeng; Zhao, YaLei; Yan, QiShe

    2015-01-01

    Bi₇O₉I₃, a kind of visible-light-responsive photocatalyst, with hierarchical micro/nano-architecture was successfully synthesized by oil-bath heating method, with ethylene glycol as solvent, and applied to degrade sulfonamide antibiotics. The as-prepared product was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflection spectra and scanning electron microscopy (SEM). XRD and XPS tests confirmed that the product was indeed Bi₇O₉I₃. The result of SEM observation shows that the as-synthesized Bi₇O₉I₃ consists of a large number of micro-sheets with parallel rectangle structure. The optical test exhibited strong photoabsorption in visible light irradiation, with 617 nm of absorption edges. Moreover, the difference in the photocatalytic efficiency of as-prepared Bi₇O₉I₃ at different seasons of a whole year was investigated in this study. The chemical oxygen demand removal efficiency and concentration of NO(3)(-) and SO(4)(2-) of solution after reaction were also researched to confirm whether degradation of the pollutant was complete; the results indicated a high mineralization capacity of Bi₇O₉I₃. The as-synthesized Bi₇O₉I₃exhibits an excellent oxidizing capacity of sulfadiazine sodium and favorable stability during the photocatalytic reaction.

  9. Facile synthesis of Ag-ZnO hybrid nanospindles for highly efficient photocatalytic degradation of methyl orange.

    Science.gov (United States)

    Kuriakose, Sini; Choudhary, Vandana; Satpati, Biswarup; Mohapatra, Satyabrata

    2014-09-07

    Highly photocatalytically active Ag nanoparticle decorated ZnO nanospindles were synthesized by a facile wet chemical method. The structural and optical properties of the as-synthesized materials were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and high resolution TEM (HRTEM) with energy dispersive X-ray spectroscopy, UV-visible absorption spectroscopy and Raman spectroscopy. The photocatalytic activity of these nanostructures was evaluated by analyzing sunlight driven degradation of methyl orange (MO) dye and it was observed that Ag nanoparticle modified ZnO nanospindles show significantly enhanced photocatalytic activity for degradation of MO, as compared to ZnO nanospindles. We attribute the observed enhanced photocatalytic activity of Ag nanoparticle decorated ZnO nanospindles to their improved sunlight utilization efficiency and the efficient suppression of recombination of photogenerated charge carriers due to the electron scavenging action of Ag nanoparticles and the interfacial electron transfers due to the Schottky junction between Ag nanoparticles and ZnO nanospindles.

  10. Degradation in the efficiency of glass Resistive Plate Chambers operated without external gas supply

    Science.gov (United States)

    Baesso, P.; Cussans, D.; Thomay, C.; Velthuis, J.; Burns, J.; Quillin, S.; Stapleton, M.; Steer, C.

    2015-06-01

    Resistive plate chambers (RPC) are particle detectors commonly used by the high energy physics community. Their normal operation requires a constant flow of gas mixture to prevent self-poisoning which reduces the chamber's capability to detect particles. We studied how quickly the efficiency of two RPCs drops when operated in sealed mode, i.e. without refreshing the gas mixture. The test aim is to determine how RPCs could be used as particle detectors in non-laboratory applications, such as those exploiting muon tomography for geological imaging or homeland security. The two sealed RPCs were operated in proportional mode for a period of more than three months, and their efficiencies were recorded continuously and analysed in 8-hours intervals. The results show that the efficiency drops on average by 0.79 ± 0.01 % every 24 hours of operation and returns close to the initial value after purging the old gas mixture and flushing the chambers with fresh gas.

  11. Efficient production of mannan-degrading enzymes by the basidiomycete Sclerotium rolfsii.

    Science.gov (United States)

    Sachslehner, A; Haltrich, D; Gübitz, G; Nidetzky, B; Kulbe, K D

    1998-01-01

    Sclerotium rolfsii CBS 191.62 was cultivated on a number of carbon (C) sources, including mono- and disaccharides, as well as on polysaccharides, to study the formation of different mannan-degrading enzyme activities. Highest levels of mannanase activity were obtained when alpha-cellulose-based media were used for growth, but formation of mannanase could not be enhanced by employing galactomannan as the only carbon source. Although both xylanase and cellulase formation was almost completely repressed when S. rolfsii was grown on more readily metabolizable carbohydrates, including glucose or mannose, considerable amounts of mannanase activity were secreted under these growth conditions. Enhanced mannanase production only commenced when glucose was depleted in the medium. The maximal mannanase activity of 240 IU/mL obtained in a laboratory fermentation is remarkable. Mannanase activity formed under these derepressed conditions could be mainly attributed to one major, acidic mannanase isoenzyme with a pI value of 2.75.

  12. Graphene-SnO2 composites for highly efficient photocatalytic degradation of methylene blue under sunlight.

    Science.gov (United States)

    Seema, Humaira; Christian Kemp, K; Chandra, Vimlesh; Kim, Kwang S

    2012-09-07

    Graphene sheets decorated with SnO(2) nanoparticles (RGO-SnO(2)) were prepared via a redox reaction between graphene oxide (GO) and SnCl(2). Graphene oxide (GO) was reduced to graphene (RGO) and Sn(2+) was oxidized to SnO(2) during the redox reaction, leading to a homogeneous distribution of SnO(2) nanoparticles on RGO sheets. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images show uniform distribution of the nanoparticles on the RGO surface and high-resolution transmission electron microscopy (HRTEM) shows an average particle size of 3-5 nm. The RGO-SnO(2) composite showed an enhanced photocatalytic degradation activity for the organic dye methylene blue under sunlight compared to bare SnO(2) nanoparticles. This result leads us to believe that the RGO-SnO(2) composite could be used in catalytic photodegradation of other organic dyes.

  13. Preparation of immobilized coating Fenton-like catalyst for high efficient degradation of phenol.

    Science.gov (United States)

    Wang, Jiankang; Yao, Zhongping; Wang, Yajing; Xia, Qixing; Chu, Huiya; Jiang, Zhaohua

    2017-05-01

    In this study, solid acid amorphous Fe 3 O 4 /SiO 2 ceramic coating decorated with sulfur on Q235 carbon steel as Fenton-like catalyst for phenol degradation was successfully prepared by plasma electrolytic oxidation (PEO) in silicate electrolyte containing Na 2 S 2 O 8 as sulfur source. The surface morphology and phase composition were characterized by SEM, EDS, XRD and XPS analyses. NH 3 -TPD was used to evaluate surface acidity of PEO coating. The results indicated that sulfur decorated amorphous Fe 3 O 4 /SiO 2 ceramic coatings with porous structure and higher acid strength had the similar pore size and the surface became more and more uneven with the increase of Na 2 S 2 O 8 in the silicate electrolyte. The Fenton-like catalytic activity of sulfur decorated PEO coatings was also evaluated. In contrast to negligible catalytic activity of sulfur undecorated PEO coating, catalytic activity of sulfur decorated PEO coating was excellent and PEO coating prepared with 3.0 g Na 2 S 2 O 8 had the highest catalytic activity which could degrade 99% of phenol within 8 min under circumneutral pH. The outstanding performance of sulfur decorated PEO coating was attributed to strong acidic microenvironment and more Fe 2+ on the surface. The strong acid sites played a key factor in determining catalytic activity of catalyst. In conclusion, rapid phenol removal under circumneutral pH and easier separation endowed it potential application in wastewater treatment. In addition, this strategy of preparing immobilized solid acid coating could provide guidance for designing Fenton-like catalyst with excellent catalytic activity and easier separation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Real-time monitoring energy efficiency and performance degradation of condensing boilers

    NARCIS (Netherlands)

    Baldi, S.; Le, Q.T.; Holub, O.; Endel, P

    2017-01-01

    Condensing boilers achieve higher efficiency than traditional boilers by using waste heat in flue gases to preheat cold return water entering the boiler. Water vapor produced during combustion is condensed into liquid form, thus recovering its latent heat of vaporization, leading to around 10–12%

  15. Efficient degradation of gluten by a prolyl endoprotease in a gastrointestinal model: Implications for coeliac disease

    NARCIS (Netherlands)

    Mitea, C.; Havenaar, R.; Wouter Drijfhout, J.; Edens, L.; Dekking, L.; Koning, F.; Dekking, E.H.A.

    2008-01-01

    Background: Coeliac disease is caused by an immune response to gluten. As gluten proteins are proline rich they are resistant to enzymatic digestion in the gastrointestinal tract, a property that probably contributes to the immunogenic nature of gluten. Aims: This study determined the efficiency of

  16. Regenerating degraded soils and increasing water use efficiency on vegetable farms in Uruguay through ecological intensification

    NARCIS (Netherlands)

    Alliaume, F.

    2016-01-01

    This thesis investigated alternative soil management strategies for vegetable crop systems and their hypothesized effects on increasing systems resilience by sequestering soil carbon, increasing the efficiency of water use, and reducing erosion. The goal was to contribute knowledge on and tools for

  17. Efficient degradation of rhodamine B using modified graphite felt gas diffusion electrode by electro-Fenton process.

    Science.gov (United States)

    Tian, Jiangnan; Olajuyin, Ayobami Matthew; Mu, Tingzhen; Yang, Maohua; Xing, Jianmin

    2016-06-01

    The electro-Fenton (EF) process treatment of 0.1-M (rhodamine B) RhB solution was studied with different graphite cathode materials, and graphite felt (GF) was selected as a promising material in further investigation. Then, the degradation performances of gas diffusion electrode (GDE) and graphite felt (GF) were compared, and GDE was confirmed to be more efficient in RhB removal. The operational parameters such as Fe(2+) dosage and current density were optimized, and comparison among different modified methods-polytetrafluoroethylene-carbon black (PTFE-CB), polytetrafluoroethylene-carbon nanotube (PTFE-CNT), electrodeposition-CB, and electrodeposition-CNT-showed 98.49 % RhB removal by PTFE-CB-modified cathode in 0.05 M Na2SO4 at a current density of 50 A/m(2) and an air flow rate of 1 L/min after 20 min. Meanwhile, after cathode modified by PTFE-CB, the mineralization efficiency and mineralization current efficiency performed absolutely better than the pristine one. Cyclic voltammograms, SEM images, contact angles, and BET surface area were carried out to demonstrate stronger current responses and higher hydrophilicity of GF after modified. The value of biochemical oxygen demand/chemical oxygen demand (BOD5/COD) increased from 0.049 to 0.331 after 90-min treatment, suggesting the solution was biodegradable, and the modified cathode was confirmed to be stable after ten circle runs. Finally, a proposed degradation pathway of RhB was put forward.

  18. Manganese oxyhydroxide and oxide nanofibers for high efficiency degradation of organic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Peng Xinsheng [State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Ichinose, Izumi [Organic Nanomaterials Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2011-01-07

    Ultrathin MnOOH nanofibers were synthesized on a large scale from diluted Mn(NO{sub 3}){sub 2} aqueous solution at room temperature. These MnOOH nanofibers were shape-reservedly converted into Mn{sub 3}O{sub 4} and MnO{sub 2} nanofibers by post-heat treatment in air at 400 deg. C and 600 deg. C for 1 h, respectively. The morphology and crystalline structures of the nanofibers were characterized by electronic microscopes and x-ray diffraction. These nanofibers had good crystalline structures. These nanofibers were in bundles with a diameter of 25 nm composed of 3-5 nm fine crystalline nanofibers. The Mn{sub 3}O{sub 4} nanofibers had a specific surface area of 71 m{sup 2} g{sup -1} and demonstrated highly catalytic degradation of the organic pollutant methylene blue with the assistance of H{sub 2}O{sub 2} at room temperature.

  19. Brewer's yeast efficiently degrades phytate phosphorus in a corn-soybean meal diet during soaking treatment.

    Science.gov (United States)

    Chu, Gyo-Moon; Ohmori, Hideyuki; Kawashima, Tomoyuki; Funaba, Masayuki; Matsui, Tohru

    2009-08-01

    Microbes such as yeast and Aspergillus are known to produce phytase, and Aspergillus phytase has been used as a feed additive for improving phytate-phosphorus bioavailability in monogastric animals. We measured phytase activity in some by-products from fermented food and beverage productions by yeast and Aspergillus. The phytase activity was as high as 3577 and 2225 PU/kg DM in raw and dried brewer's yeasts, respectively. On the other hand, the phytase activity was approximately 400 PU/kg DM in white-wine yeast and red-wine yeast. The phytase activity was further low in natto (fermented soybean) residue, soy sauce cake, rice brewer's grain and the activity was not detected in dried corn-barley distiller's grain with soluble and sweet-potato distiller's residue. The stability of phytase against pepsin was much lower in the brewer's yeast than in an Aspergillus phytase preparation. On the other hand, the addition of raw brewer's yeast effectively degraded phytate phosphorus in a corn-soybean meal diet during soaking. These results suggest that phytase in the examined by-products is not suitable for the phytase source of conventional diets, but that the soaking treatment with a raw brewer's yeast is an alternative method for improving phytate-phosphorus bioavailability in corn-soybean meal diets for pigs.

  20. Highly efficient photocatalytic degradation of organic dyes by Cu doped ZnO nanostructures.

    Science.gov (United States)

    Kuriakose, Sini; Satpati, Biswarup; Mohapatra, Satyabrata

    2015-10-14

    Copper doped ZnO nanostructures have been synthesized by a facile wet chemical method. Structural properties of as-synthesized nanomaterials have been studied by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) with energy dispersive X-ray spectroscopy, while UV-visible absorption spectroscopy and Raman spectroscopy have been used to study their optical properties. Sunlight driven photocatalytic degradation of methylene blue (MB) and methyl orange (MO) dyes in water was used to evaluate the photocatalytic activities of Cu doped ZnO nanostructures using UV-visible absorption spectroscopy. The results showed that there is an optimum Cu doping level which leads to the highly enhanced photocatalytic activity of Cu doped ZnO nanostructures, as compared to pure ZnO nanostructures. A mechanism for the enhanced photocatalytic activity of Cu-ZnO nanostructures is tentatively proposed. The enhanced photocatalytic activity of Cu-ZnO nanostructures is attributed to the combined effects of improved separation of photogenerated charge carriers due to optimal Cu doping in ZnO nanostructures and the formation of ZnO-CuO nanoheterojunctions.

  1. Highly efficient visible light mediated azo dye degradation through barium titanate decorated reduced graphene oxide sheets

    Science.gov (United States)

    Rastogi, Monisha; Kushwaha, H. S.; Vaish, Rahul

    2016-03-01

    This study investigates BaTiO3 decorated reduced graphene oxide sheets as a potential visible light active catalyst for dye degradation (Rhodamine B). The composites were prepared through conventional hydrothermal synthesis technique using hydrazine as a reducing agent. A number of techniques have been employed to affirm the morphology, composition and photocatalytic properties of the composites; these include UV-visible spectrophotoscopy that assisted in quantifying the concentration difference of Rhodamine B. The phase homogeneity of the composites was examined through x-ray powder diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) was employed to confirm the orientation of the BaTiO3 particles over the reduced graphene oxide sheets. Photoluminescence (PL) emission spectra assisted in determining the surface structure and excited state of the catalyst. Fourier transformed-infrared (FTIR) spectra investigated the vibrations and adsorption peak of the composites, thereby ascertaining the formation of reduced graphene oxide. In addition, diffuse reflectance spectroscopy (DRS) demonstrated an enhanced absorption in the visible region. The experimental investigations revealed that graphene oxide acted as charge collector and simultaneously facilitated surface adsorption and photo-sensitization. It could be deduced that BaTiO3-reduced graphene oxide composites are of significant interest the field of water purification through solar photocatalysis. [Figure not available: see fulltext.

  2. Self-Organized TiO₂-MnO₂ Nanotube Arrays for Efficient Photocatalytic Degradation of Toluene.

    Science.gov (United States)

    Nevárez-Martínez, María C; Kobylański, Marek P; Mazierski, Paweł; Wółkiewicz, Jolanta; Trykowski, Grzegorz; Malankowska, Anna; Kozak, Magda; Espinoza-Montero, Patricio J; Zaleska-Medynska, Adriana

    2017-03-31

    Vertically oriented, self-organized TiO₂-MnO₂ nanotube arrays were successfully obtained by one-step anodic oxidation of Ti-Mn alloys in an ethylene glycol-based electrolyte. The as-prepared samples were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), UV-Vis absorption, photoluminescence spectroscopy, X-ray diffraction (XRD), and micro-Raman spectroscopy. The effect of the applied potential (30-50 V), manganese content in the alloy (5-15 wt. %) and water content in the electrolyte (2-10 vol. %) on the morphology and photocatalytic properties was investigated for the first time. The photoactivity was assessed in the toluene removal reaction under visible light, using low-powered LEDs as an irradiation source (λ max = 465 nm). Morphology analysis showed that samples consisted of auto-aligned nanotubes over the surface of the alloy, their dimensions were: diameter = 76-118 nm, length = 1.0-3.4 μm and wall thickness = 8-11 nm. It was found that the increase in the applied potential led to increase the dimensions while the increase in the content of manganese in the alloy brought to shorter nanotubes. Notably, all samples were photoactive under the influence of visible light and the highest degradation achieved after 60 min of irradiation was 43%. The excitation mechanism of TiO₂-MnO₂ NTs under visible light was presented, pointing out the importance of MnO₂ species for the generation of e - and h⁺.

  3. Highly efficient photocatalytic degradation of methylene blue by PoPD/TiO2 nanocomposite.

    Directory of Open Access Journals (Sweden)

    Chuanxi Yang

    Full Text Available The poly-o-phenylenediamine (PoPD/TiO2 nanocomposite was successfully synthesized via 'in situ' oxidative polymerization method. The modified photocatalysts were characterized by BET, scanning electron microscopy (SEM, transmission electron microscopy (TEM, X-ray diffraction (XRD, Fourier-transform infrarad spectra (FT-IR, thermogravimrtic analysis (TGA, X-ray photoelectron spectroscopy (XPS, Ultraviolet-visible diffuse reflectance spectrum (UV-Vis DRS and Photocurrent Test. The results showed that the PoPD exists on the surface of TiO2, the presence of PoPD does not impact on the lattice structure and grain size of TiO2, and the presence of PoPD enhances the visible response and photoelectric property. The photocatalytic degradation of methylene blue (MB was chosen as a model reaction to evaluate the photocatalytic activities of TiO2 and PoPD/TiO2. The optimal preparation condition was the molar ratio of oPD to TiO2 = 3:1, HCl concentration = 1.2 mol/L, the molar ratio of APS to oPD = 1:1. The apparent first-order rate constant kapp of PoPD/TiO2 nanocomposite was 0.0098 min-1, which is 6 times higher than TiO2 (0.0016 min-1. Meanwhile, the PoPD/TiO2 nanocomposites showed excellent photocatalytic stability, and the photocatalytic stability was depended on the stability of structure. At last, the photocatalytic mechanism of POPD/TiO2 nanocomposites was also proposed based on the synergetic effect between TiO2 and PoPD.

  4. Efficient visible-light photocatalytic degradation system assisted by conventional Pd catalysis

    Science.gov (United States)

    Yu, Yanlong; He, Tao; Guo, Lingju; Yang, Yajun; Guo, Limei; Tang, Yue; Cao, Yaan

    2015-01-01

    Different approaches like doping and sensitization have been used to develop photocatalysts that can lead to high reactivity under visible-light illumination, which would allow efficient utilization of solar irradiation and even interior lighting. We demonstrated a conceptually different approach by changing reaction route via introducing the idea of conventional Pd catalysis used in cross-coupling reactions into photocatalysis. The –O–Pd–Cl surface species modified on Ni-doped TiO2 can play a role the same as that in chemical catalysis, resulting in remarkably enhanced photocatalytic activity under visible-light irradiation. For instance, Pd/Ni-TiO2 has much higher activity than N-TiO2 (about 3 ~ 9 times for all of the 4-XP systems) upon irradiation with wavelength of 420 nm. The catalytically active Pd(0) is achieved by reduction of photogenerated electrons from Ni-TiO2. Given high efficient, stable Pd catalysts or other suitable chemical catalysts, this concept may enable realization of the practical applications of photocatalysis. PMID:25825365

  5. Efficient Photocatalytic Degradation of Rhodamine B Dye by Aligned Arrays of Self-Assembled Hydrogen Titanate Nanotubes

    Directory of Open Access Journals (Sweden)

    Sriparna Chatterjee

    2014-01-01

    Full Text Available We show that an aligned array of hydrothermally grown, multiwalled hydrogen titanate (H2Ti3O7 nanotubes—anchored to both faces of a metallic Ti foil—acts as an efficient photocatalyst. We studied the degradation of rhodamine B dye in the presence of the nanostructured photocatalyst under UV irradiation, by monitoring the optical absorption of the dye. Rhodamine B was chosen as a representative—and particularly harmful—industrial pollutant dye. The inner and outer diameters of the H2Ti3O7 nanotubes were 5 nm and 10 nm, respectively. The nanotube array catalyst is recyclable and structurally stable. Most importantly, it shows comparable or higher photodecomposition rate constant than those of both H2Ti3O7 nanotube powder and P-25 (Degussa. The enhanced photocatalytic performance may be ascribed to the nanotube array having a superhydrophilic surface with a high accessible surface area.

  6. Biotemplated Mesoporous TiO2/SiO2 Composite Derived from Aquatic Plant Leaves for Efficient Dye Degradation

    Directory of Open Access Journals (Sweden)

    Zhiying Yan

    2017-03-01

    Full Text Available The biotemplating technique is an environmental-protective high-efficiency new technology by which the resulting TiO2 may simultaneously attain the duplication of structure and self-doping elements from biotemplate materials, which is highly desirable for photocatalytic applications. In this paper, aquatic plant leaves—including reed, water hyacinth, and duckweed—were used as both templates and silicon precursors to successfully synthesize biomorphic TiO2/SiO2 composite with mesoporous structures. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, N2 adsorption–desorption, and UV–visible diffuse reflectance spectra were applied to characterize the microstructures of the samples. The results show that all TiO2/SiO2 composites are mainly composed of an anatase phase with mesoporous structure and possess high specific surface area. Compared with commercial Degussa P25 TiO2, all TiO2/SiO2 samples display intensive light-harvesting efficiency, particularly in the visible light range. The activities were evaluated by using gentian violet as a target for photocatalytic degradation experiments under simulated solar irradiation. The TiO2/SiO2 samples templated by reed and water hyacinth leaves exhibit high activity, while the TiO2/SiO2 samples obtained from duckweed are inferior to P25 in the degradation of gentian violet. A synergistic effect of SiO2 incorporation and structural construction through biotemplating is proposed to be beneficial to photocatalytic activity.

  7. Reduced sampling efficiency causes degraded Vernier hyperacuity with normal aging: Vernier acuity in position noise.

    Science.gov (United States)

    Li, Roger W; Brown, Brian; Edwards, Marion H; Ngo, Charlie V; Chat, Sandy W; Levi, Dennis M

    2012-01-01

    Vernier acuity, a form of visual hyperacuity, is amongst the most precise forms of spatial vision. Under optimal conditions Vernier thresholds are much finer than the inter-photoreceptor distance. Achievement of such high precision is based substantially on cortical computations, most likely in the primary visual cortex. Using stimuli with added positional noise, we show that Vernier processing is reduced with advancing age across a wide range of noise levels. Using an ideal observer model, we are able to characterize the mechanisms underlying age-related loss, and show that the reduction in Vernier acuity can be mainly attributed to the reduction in efficiency of sampling, with no significant change in the level of internal position noise, or spatial distortion, in the visual system.

  8. Degradable and biocompatible nanoparticles decorated with cyclic RGD peptide for efficient drug delivery to hepatoma cells in vitro.

    Science.gov (United States)

    Loyer, Pascal; Bedhouche, Wahib; Huang, Zhi Wei; Cammas-Marion, Sandrine

    2013-10-01

    Amphiphilic derivatives of poly(benzyl malate) were synthesized and characterized with the aim of being used as degradable and biocompatible building blocks for the design of functional nanoparticles (NPs). An anti-cancer model drug, doxorubicin, has been successfully encapsulated into the prepared NPs and its release profile has been evaluated in water and in culture medium. NPs bearing biotin molecules were prepared either for site-specific drug delivery via the targeting of biotin receptors overexpressed on the surface of several cancer cells, or for grafting biotinylated cyclic RGD peptide onto their surface using the strong and highly specific interactions between biotin and the streptavidin protein. We have shown that this binding did not affect dramatically the physico-chemical properties of the corresponding NPs. Cyclic RGD grafted fluorescent NPs were more efficiently uptaken by the HepaRG hepatoma cells than biotinylated fluorescent NPs. Furthermore, the targeting of HepaRG hepatoma cells with NPs bearing cyclic RGD was very efficient and much weaker for HeLa and HT29 cell lines confirming that cyclic RGD is a suitable targeting agent for liver cells. Our results also provide a new mean for rapid screening of short hepatotropic peptides in order to design NPs showing specific liver targeting properties. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Rapid, Efficient and Versatile Strategies for Functionally Sophisticated Polymers and Nanoparticles: Degradable Polyphosphoesters and Anisotropic Distribution of Chemical Functionalities

    Science.gov (United States)

    Zhang, Shiyi

    The overall emphasis of this dissertation research included two kinds of asymmetrically-functionalized nanoparticles with anisotropic distributions of chemical functionalities, three degradable polymers synthesized by organocatalyzed ring-opening polymerizations, and two polyphosphoester-based nanoparticle systems for various biomedical applications. Inspired by the many hierarchical assembly processes that afford complex materials in Nature, the construction of asymmetrically-functionalized nanoparticles with efficient surface chemistries and the directional organization of those building blocks into complex structures have attracted much attention. The first method generated a Janus-faced polymer nanoparticle that presented two orthogonally click-reactive surface chemistries, thiol and azido. This robust method involved reactive functional group transfer by templating against gold nanoparticle substrates. The second method produced nanoparticles with sandwich-like distribution of crown ether functionalities through a stepwise self-assembly process that utilized crown ether-ammonium supramolecular interactions to mediate inter-particle association and the local intra-particle phase separation of unlike hydrophobic polymers. With the goal to improve the efficiency of the production of degradable polymers with tunable chemical and physical properties, a new type of reactive polyphosphoester was synthesized bearing alkynyl groups by an organocatalyzed ring-opening polymerization, the chemical availability of the alkyne groups was investigated by employing "click" type azide-alkyne Huisgen cycloaddition and thiol-yne radical-mediated reactions. Based on this alkyne-functionalized polyphosphoester polymer and its two available "click" type reactions, two degradable nanoparticle systems were developed. To develop the first system, the well defined poly(ethylene oxide)-block-polyphosphester diblock copolymer was transformed into a multifunctional Paclitaxel drug

  10. Pattern Water Use Efficiency perspective on degradation and recovery of shrublands across Mediterranean to Arid transition zones

    Science.gov (United States)

    Shoshany, Maxim

    2017-04-01

    Shrublands cover a total of 12.7 million km2 , a considerable part of them along semi-arid to arid transition zones. Varying patterns of shrubs, grasses and barren land along such climatic gradients express the spatial dimension of climate change and human disturbance which attracted limited attention in the eco-geomorphic literature. Questions concerning relationships between rainfall, shrublands biomass and their patterns are fundamental for the understanding of these ecosystems response to the expected changes in water availability due to global warming and the increase in human disturbance to natural ecosystems following World population growth. While processes leading to the formation of patterns had attracted considerable attention, the spatial dimension of Water Use Efficiency (WUE) which is a parameter measuring ecosystems productivity in relation to water availability is severely missing. Relative shrub cover is a primary estimator of the fraction of water utilized for shrubs growth. Edge effects must be considered as well in fragmented ecosystems in general and in hot regions in particular since soil temperature in hot regions which frequently exceed 50oC during summer months decreases photosynthesis and productivity in plants bordering bare soil. This edge effect is decreasing with the increase in shrubs' height. Pattern Water Use Efficiency describes the combined effect of shrub cover, shrub height and shrub patches edge zone proportion on water use efficiency. In my presentation I will first present mapping od PWUEs across Mediterranean to arid transition zones in the Eastern Mediterranean. Then I will present several mathematical models describing PWUE for simulated patterns, searching for the spatial parameterization providing the highest sensitivity to patterns responses to changes in habitat conditions. Such simulations would allow us to discuss several PWUE strategies for shrublands recovery under the current scenarios of climate change and human

  11. Mn/Ti-doped carbon xerogel for efficient catalysis of microcystin-LR degradation in the water surface discharge plasma reactor.

    Science.gov (United States)

    Xin, Qing; Zhang, Yi; Li, Zhongjian; Lei, Lecheng; Yang, Bin

    2015-11-01

    The novel catalysts of Mn/Ti-doped carbon xerogel (CX) were synthesized for efficient degradation of microcystin-LR (MC-LR) in the water surface discharge plasma reactor. The degradation efficiency of 79.7% was obtained in 6 min with 0.5 wt% Ti impregnation of CX, and it would be increased with higher amount of Ti. In particular, Mn-doped CX resulted in larger mesoporous particle diameter and higher porosity in the matrix, and thereby, the highest efficiency of 88.6% was achieved for CX-Ti-Mn. The possible degradation pathway of MC-LR was elucidated on the basis of the LC-MS analysis. It demonstrated that Adda chain was cleaved from the MC-LR cyclic peptide by OH radical attack after plasma discharge in the presence of catalysts, and the generated nontoxic products can be further easily degraded in the biological treatment. Therefore, Mn/Ti-doped carbon xerogel is promising as the catalyst for the improvement of MC-LR degradation in the water surface discharge plasma reactor.

  12. DDT degradation efficiency and ecotoxicological effects of two types of nano-sized zero-valent iron (nZVI) in water and soil.

    Science.gov (United States)

    El-Temsah, Yehia S; Sevcu, Alena; Bobcikova, Katerina; Cernik, Miroslav; Joner, Erik J

    2016-02-01

    Nano-scale zero-valent iron (nZVI) has been conceived for cost-efficient degradation of chlorinated pollutants in soil as an alternative to e.g permeable reactive barriers or excavation. Little is however known about its efficiency in degradation of the ubiquitous environmental pollutant DDT and its secondary effects on organisms. Here, two types of nZVI (type B made using precipitation with borohydride, and type T produced by gas phase reduction of iron oxides under H2) were compared for efficiency in degradation of DDT in water and in a historically (>45 years) contaminated soil (24 mg kg(-1) DDT). Further, the ecotoxicity of soil and water was tested on plants (barley and flax), earthworms (Eisenia fetida), ostracods (Heterocypris incongruens), and bacteria (Escherichia coli). Both types of nZVI effectively degraded DDT in water, but showed lower degradation of aged DDT in soil. Both types of nZVI had negative impact on the tested organisms, with nZVI-T giving least adverse effects. Negative effects were mostly due to oxidation of nZVI, resulting in O2 consumption and excess Fe(II) in water and soil. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Improved WO{sub 3} photocatalytic efficiency using ZrO{sub 2} and Ru for the degradation of carbofuran and ampicillin

    Energy Technology Data Exchange (ETDEWEB)

    Gar Alalm, Mohamed, E-mail: mohamed.alkalla@ejust.edu.eg [Department of Public Works Engineering, Faculty of Engineering, Mansoura University, 35516 Aldakahleya (Egypt); Ookawara, Shinichi [Department of Chemical Engineering, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552 (Japan); Fukushi, Daisuke [Toshiba Materials co., Ltd., Development Group, Development and Engineering Department, 8 Shinsugita-Cho, Isogo-Ku, Yokohama 235-8522 (Japan); Department of Innovative and Engineered Materials, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259-S2-16, Nagatsuta-cho, Midori-ku, Yokohama 226-8503 (Japan); Sato, Akira [Toshiba Materials co., Ltd., Development Group, Development and Engineering Department, 8 Shinsugita-Cho, Isogo-Ku, Yokohama 235-8522 (Japan); Tawfik, Ahmed [Department of Environmental Engineering, School of Energy, Environmental, Chemical and Petrochemical, Egypt-Japan University of Science and Technology (E-Just), New Borg El Arab City, 21934 Alexandria (Egypt)

    2016-01-25

    Highlights: • A nano-scale photocatalyst of WO{sub 3} and ZrO{sub 2} has been prepared. • Ruthenium has been added to photocatalyst to enhance the photocatalytic activity. • Degradation of ampicillin and carbofuran by solar light has been investigated. • Reusability of Ru/WO{sub 3}/ZrO{sub 2} has been investigated and showed 92% of initial efficiency. - Abstract: The photocatalytic degradation of carbofuran (pesticide) and ampicillin (pharmaceutical) using synthesized WO{sub 3}/ZrO{sub 2} nanoparticles under simulated solar light was investigated. Transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectra analyses were used to characterize the prepared catalysts. The optimum ratio of WO{sub 3} to ZrO{sub 2} was determined to be 1:1 for the degradation of both contaminants. The degradation of carbofuran and ampicillin by WO{sub 3}/ZrO{sub 2} after 240 min of irradiation was 100% and 96%, respectively. Ruthenium (Ru) was employed as an additive to WO{sub 3}/ZrO{sub 2} to enhance the photocatalytic degradation rate. Ru/WO{sub 3}/ZrO{sub 2} exhibited faster degradation rates than WO{sub 3}/ZrO{sub 2}. Furthermore, 100% and 97% degradation of carbofuran and ampicillin, respectively, was achieved using Ru/WO{sub 3}/ZrO{sub 2} after 180 min of irradiation. The durability of the catalyst was investigated by reusing the same suspended catalyst, which achieved 92% of its initial efficiency. The photocatalytic degradation of ampicillin and carbofuran followed pseudo-first order kinetics according to the Langmuir–Hinshelwood model.

  14. Visible light responsive Cu2MoS4 nanosheets incorporated reduced graphene oxide for efficient degradation of organic pollutant

    Science.gov (United States)

    Rameshbabu, R.; Vinoth, R.; Navaneethan, M.; Harish, S.; Hayakawa, Y.; Neppolian, B.

    2017-10-01

    Visible light active copper molybdenum sulfide (Cu2MoS4) nanosheets were successfully anchored on reduced graphene oxide (rGO) using facile hydrothermal method. During the hydrothermal reaction, reduction of graphene oxide into rGO and the formation of Cu2MoS4 nanosheets were successfully obtained. The charge transfer interaction between the rGO sheets and Cu2MoS4 nanosheets extended the absorption to visible region in comparison with bare Cu2MoS4 nanosheets i.e without rGO sheets. Furthermore, the notable photoluminescence quenching observed for Cu2MoS4/rGO nanocomposite revealed the effective role of rGO towards the significant inhibition of electron-hole pair recombination. The photocatalytic efficiencies of bare Cu2MoS4 and Cu2MoS4/rGO nanocomposite was evaluated for the degradation of methyl orange dye under visible irradiation (λ > 420 nm). A maximum photodegradation efficiency of 99% was achieved for Cu2MoS4/rGO nanocomposite, while only 64% photodegradation was noted for bare Cu2MoS4. The enhanced optical absorption in visible region, high surface area, and low charge carrier recombination in the presence of rGO sheets were the main reasons for the enhancement in photodegardation of MO dye. In addition, the resultant Cu2MoS4/rGO nanocomposite was found to be reusable for five successive cycles without significant loss in its photocatalytic performance.

  15. Kinetics and energy efficiency for the degradation of 1,4-dioxane by electro-peroxone process.

    Science.gov (United States)

    Wang, Huijiao; Bakheet, Belal; Yuan, Shi; Li, Xiang; Yu, Gang; Murayama, Seiichi; Wang, Yujue

    2015-08-30

    Degradation of 1,4-dioxane by ozonation, electrolysis, and their combined electro-peroxone (E-peroxone) process was investigated. The E-peroxone process used a carbon-polytetrafluorethylene cathode to electrocatalytically convert O2 in the sparged ozone generator effluent (O2 and O3 gas mixture) to H2O2. The electro-generated H2O2 then react with sparged O3 to yield aqueous OH, which can in turn oxidize pollutants rapidly in the bulk solution. Using p-chlorobenzoic acid as OH probe, the pseudo-steady concentration of OH was determined to be ∼0.744×10(-9)mM in the E-peroxone process, which is approximately 10 and 186 times of that in ozonation and electrolysis using a Pt anode. Thanks to its higher OH concentration, the E-peroxone process eliminated 96.6% total organic carbon (TOC) from a 1,4-dioxane solution after 2h treatment with a specific energy consumption (SEC) of 0.376kWhg(-1) TOCremoved. In comparison, ozonation and electrolysis using a boron-doped diamond anode removed only ∼6.1% and 26.9% TOC with SEC of 2.43 and 0.558kWhg(-1) TOCremoved, respectively. The results indicate that the E-peroxone process can significantly improve the kinetics and energy efficiency for 1,4-dioxane mineralization as compared to the two individual processes. The E-peroxone process may thus offer a highly effective and energy-efficient alternative to treat 1,4-dioxane wastewater. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. CdS-sensitized TiO{sub 2} in phenazopyridine photo-degradation: Catalyst efficiency, stability and feasibility assessment

    Energy Technology Data Exchange (ETDEWEB)

    Zyoud, Ahed H.; Zaatar, Nidal; Saadeddin, Iyad [Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine (Country Unknown); Ali, Cheknane [Laboratoire d' Etude et Developpement des materiaux Dielectriques et Semiconducteurs, Universite Amar Telidji de Laghouat, Laghouat (Algeria); Park, DaeHoon; Campet, Guy [Institut de Chimie de la Matiere Condensee de Bordeaux (ICMCB), 87 Avenue du Dr. A Schweitzer, 33608 Pessac (France); Hilal, Hikmat S., E-mail: hikmathilal@yahoo.com [Department of Chemistry, An-Najah N. University, PO Box 7, Nablus, West Bank, Palestine (Country Unknown)

    2010-01-15

    Mineralization of phenazopyridine, 1, in water, under solar-simulator radiation was efficiently achieved using nanoparticle CdS-sensitized rutile TiO{sub 2}, TiO{sub 2}/CdS, 2, as photo-catalysts. Despite that, 2 showed two main drawbacks. Firstly, the system was difficult to recover by simple filtration, and demanded centrifugation. Secondly, the sensitizer CdS showed relatively high tendency to leach out hazardous Cd{sup 2+} ions under photo-degradation reaction conditions. In an attempt to solve out such difficulties, 2 was supported onto sand surface. The sand/TiO{sub 2}/CdS system, 3, was easier to recover but showed slightly lower catalytic activity compared to 2. On the other hand, the support failed to prevent leaching of Cd{sup 2+}. This indicates limited future applicability of CdS-sensitized TiO{sub 2} photo-catalyst systems, in solar-based water purification strategies, unless leaching out tendency is completely prevented.

  17. Highly efficient electrochemical degradation of perfluorooctanoic acid (PFOA) by F-doped Ti/SnO{sub 2} electrode

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Bo, E-mail: boyang@szu.edu.cn [Department of Environmental Engineering, College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); School of Environment, POPs Research Center, Tsinghua University, Beijing 100084 (China); Jiang, Chaojin [Department of Environmental Engineering, College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); Yu, Gang, E-mail: yg-den@tsinghua.edu.cn [School of Environment, POPs Research Center, Tsinghua University, Beijing 100084 (China); Zhuo, Qiongfang [South China Institute of Environmental Sciences, The Ministry of Environment Protection, Guangzhou 510655 (China); Deng, Shubo [School of Environment, POPs Research Center, Tsinghua University, Beijing 100084 (China); Wu, Jinhua [School of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Zhang, Hong [Department of Environmental Engineering, College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China)

    2015-12-15

    Highlights: • A novel SnO{sub 2} electrode is prepared by F doping instead of the traditional Sb doping. • SnF{sub 4} as single-source precursor is used to fabricate the long-life Ti/SnO{sub 2}–F anode. • F-doped Ti/SnO{sub 2} anode possesses high OEP and decomposition ability for PFOA. • Further mechanistic detail of PFOA degradation on Ti/SnO{sub 2}–F electrode is proposed. - Abstract: The novel F-doped Ti/SnO{sub 2} electrode prepared by SnF{sub 4} as the single-source precursor was used for electrochemical degradation of aqueous perfluorooctanoic acid (PFOA). Higher oxidation reactivity and significantly longer service life were achieved for Ti/SnO{sub 2}–F electrode than Ti/SnO{sub 2}–X (X = Cl, Br, I, or Sb) electrode, which could decomposed over 99% of PFOA (50 mL of 100 mg L{sup −1}) within 30-min electrolysis. The property of Ti/SnO{sub 2}–F electrode and its electrooxidation mechanism were investigated by XRD, SEM–EDX, EIS, LSV, and interfacial resistance measurements. We propose that the similar ionic radii of F and O as well as strong electronegativity of F caused its electrochemical stability with high oxygen evolution potential (OEP) and smooth surface to generate weakly adsorbed ·OH. The preparation conditions of electrode were also optimized including F doping amount, calcination temperature, and dip coating times, which revealed the formation process of electrode. Additionally, the major mineralization product, F{sup −}, and low concentration of shorter chain perfluorocarboxylic acids (PFCAs) were detected in solution. So the reaction pathway of PFOA electrooxidation was proposed by intermediate analysis. These results demonstrate that Ti/SnO{sub 2}–F electrode is promising for highly efficient treatment of PFOA in wastewater.

  18. Self-assembly graphitic carbon nitride quantum dots anchored on TiO{sub 2} nanotube arrays: An efficient heterojunction for pollutants degradation under solar light

    Energy Technology Data Exchange (ETDEWEB)

    Su, Jingyang [Environmental Engineering Program, School of Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Zhu, Lin [Fok Ying Tung Graduate School, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Geng, Ping [Department of Chemical and Biomolecular Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Chen, Guohua, E-mail: kechengh@ust.hk [Environmental Engineering Program, School of Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Fok Ying Tung Graduate School, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Department of Chemical and Biomolecular Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China)

    2016-10-05

    Highlights: • Carbon nitride quantum dots (CNQDs) were decorated onto TiO{sub 2} nanotube arrays (NTAs). • The CNQDs/TiO{sub 2} NTAs exhibits much improved photoelectrochemical activity. • The heterojunction displays efficient removal efficiencies for RhB and phenol. • Pollutants degradation mechanism over CNQDs/TiO{sub 2} NTAs was clarified. - Abstract: In this study, an efficient heterojunction was constructed by anchoring graphitic carbon nitride quantum dots onto TiO{sub 2} nanotube arrays through hydrothermal reaction strategy. The prepared graphitic carbon nitride quantum dots, which were prepared by solid-thermal reaction and sequential dialysis process, act as a sensitizer to enhance light absorption. Furthermore, it was demonstrated that the charge transfer and separation in the formed heterojunction were significantly improved compared with pristine TiO{sub 2}. The prepared heterojunction was used as a photoanode, exhibiting much improved photoelectrochemical capability and excellent photo-stability under solar light illumination. The photoelectrocatalytic activities of prepared heterojunction were demonstrated by degradation of RhB and phenol in aqueous solution. The kinetic constants of RhB and phenol degradation using prepared photoelectrode are 2.4 times and 4.9 times higher than those of pristine TiO{sub 2}, respectively. Moreover, hydroxyl radicals are demonstrated to be dominant active radicals during the pollutants degradation.

  19. A comparison between ozonolysis and sonolysis/ozonolysis treatments for the degradation of the cytostatic drugs methotrexate and doxorubicin: Kinetic and efficiency approaches.

    Science.gov (United States)

    Somensi, Cleder A; Simionatto, Edésio L; Dalmarco, Juliana B; Gaspareto, Patrick; Radetski, Claudemir M

    2012-01-01

    Cytostatics are a major class of chemotherapy drugs with great potential to cause genotoxic and/or mutagenic effects in all organisms. Currently, hospital wastewater treatment systems (HWTS) are not able to remove these compounds and they are discharged to the environment. Thus, the objective of this study was to investigate the oxidative degradation of the cytostatic drugs doxorubicin (DOXO) [(8s,10s)-10-(4-amino-5-hydroxy-6-methyl-tetrahydro-2h-pyran-2-yloxy)-6,8,11-trihydroxy-8-(2-hydroxyacetyl)-1-methoxy-7,8,9,10-tetrahydrotetracene-5,12-dione] and methotrexate (METHO) {N-[4-[[(2,4-diamino-6-pteridinyl)methyl]methylamino]benzoyl]-L-glutamic acid} by ozonolysis alone and using a combined sonolysis/ozonolysis process on bench-scale at different pH values. Besides determining the degradation efficiency, a kinetic approach was applied to determine the reaction order and rate constants for different oxidative processes carried out at pH 7.0, which is the normal pH of hospital wastewater. The results showed that the removal efficiency of these compounds is pH-dependent. A combination of sonolysis and ozonolysis processes is more efficient than the ozonolysis process alone for the degradation of doxorubicin at all pH values, while methotrexate can easily be degraded by ozonolysis alone or sonolysis/ozonolysis methodologies at any pH.

  20. Selection and screening of microbial consortia for efficient and ecofriendly degradation of plastic garbage collected from urban and rural areas of Bangalore, India.

    Science.gov (United States)

    Skariyachan, Sinosh; Megha, M; Kini, Meghna Niranjan; Mukund, Kamath Manali; Rizvi, Alya; Vasist, Kiran

    2015-01-01

    Industrialization and urbanization have led to massive accumulation of plastic garbage all over India. The persistence of plastic in soil and aquatic environment has become ecological threat to the metropolitan city such as Bangalore, India. Present study investigates an ecofriendly, efficient and cost-effective approach for plastic waste management by the screening of novel microbial consortia which are capable of degrading plastic polymers. Plastic-contaminated soil and water samples were collected from six hot spots of urban and rural areas of Bangalore. The plastic-degrading bacteria were enriched, and degradation ability was determined by zone of clearance method. The percentage of polymer degradation was initially monitored by weight loss method, and the main isolates were characterized by standard microbiology protocols. These isolates were used to form microbial consortia, and the degradation efficiency of the consortia was compared with individual isolate and known strains obtained from the Microbial Type Culture Collection (MTCC) and Gene Bank, India. One of the main enzymes responsible for polymer degradation was identified, and the biodegradation mechanism was hypothesized by bioinformatics studies. From this study, it is evident that the bacteria utilized the plastic polymer as a sole source of carbon and showed 20-50% weight reduction over a period of 120 days. The two main bacteria responsible for the degradation were microbiologically characterized to be Pseudomonas spp. These bacteria could grow optimally at 37 °C in pH 9.0 and showed 35-40% of plastic weight reduction over 120 days. These isolates were showed better degradation ability than known strains from MTCC. The current study further revealed that the microbial consortia formulated by combining Psuedomonas spp. showed 40 plastic weight reduction over a period of 90 days. Further, extracellular lipase, one of the main enzymes responsible for polymer degradation, was identified. The

  1. Fabrication of efficient visible light activated Cu-P25-graphene ternary composite for photocatalytic degradation of methyl blue

    Science.gov (United States)

    Jin, Zheng; Duan, Wubiao; Liu, Bo; Chen, Xidong; Yang, Feihua; Guo, Jianping

    2015-11-01

    Cu-P25-graphene nanocomposite was fabricated through hydrothermal method at relatively low temperature. The technique used is P25-graphene (PG) binary composite was firstly prepared by P25 and graphite oxide (GO), and then Cu2+ ions were impregnated into PG composite. The prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) spectrum respectively. As the results showed, the Cu-P25-graphene (CPG) nanocomposites possessed the extended light absorption in visible light and better charge separation capability as compared to the pure P25 and PG system. Moreover, CPG-4 (4 mM Cu(NO3)2) showed the highest degradation rate of methyl blue (MB) under the visible light, which the removal efficiency can reach 98% after 100 min. The corresponding hydrogen evolution rate of CPG-4 was 7.9 times than pure P25. It was concluded that the synergistic effects of Cu2+ ions and graphene narrowed the band gap of TiO2 and promoted charge separation, which played significant roles for the enhancement of photoactivity of CPG composite catalysts. In addition, it was observed that the photodegradation of MB followed the first order reaction kinetics. The effects of pH values of MB solution for photocatalysts had also been investigated. The result confirmed that the optimum values of pH were found to be 7. Finally, the stability test of photocatalysts was carried out and the photocatalytic mechanism was explained concretely.

  2. A new five-coordinated copper compound for efficient degradation of methyl orange and Congo red in the absence of UV-visible radiation.

    Science.gov (United States)

    Han, Li-Juan; Kong, Ya-Jie; Yan, Ting-Jiang; Fan, Lu-Tong; Zhang, Qi; Zhao, Hua-Jun; Zheng, He-Gen

    2016-11-22

    A new copper-based coordination compound Cu 2 (2,2'-bipy) 2 (pfbz) 4 (1) (where 2,2'-bipy = 2,2'-bipyridine; pfbz = pentafluorobenzoate), was hydrothermally synthesized and structurally characterized. Compound 1 having a binuclear structure consists of two copper cations and two oxygen atoms alternately in a plane square arrangement. In the presence of very small amounts of H 2 O 2 , the catalytic properties of compound 1 for the degradation of methyl orange (MO) are excellent in the absence of UV-visible radiation. Moreover, compound 1 presents suitable properties for degradation of Congo red (CR). Our results indicated that the five-coordinated copper compound, 1, will be a promising candidate for efficient degradation of organic dyes.

  3. Magnetic diatomite(Kieselguhr)/Fe2O3/TiO2 composite as an efficient photo-Fenton system for dye degradation

    Science.gov (United States)

    Barbosa, Isaltino A.; Zanatta, Lucas D.; Espimpolo, Daniela M.; da Silva, Douglas L.; Nascimento, Leandro F.; Zanardi, Fabrício B.; de Sousa Filho, Paulo C.; Serra, Osvaldo A.; Iamamoto, Yassuko

    2017-10-01

    We explored the potential use of diatomite/Fe2O3/TiO2 composites as catalysts for heterogeneous photo-Fenton degradation of methylene blue under neutral pH. Such system consists in magnetic solids synthesized by co-precipitation with Fe2+/Fe3+ in the presence of diatomite, followed by impregnation of TiO2. The results showed that the optimal amount of the catalyst was 2.0 g L-1, since aggregation phenomena become significant above this concentration, which decreases the photodegradation activity. The catalyst is highly efficient in the degradation of methylene blue and shows an easy recovery by an external magnetic field. This allows for an effective catalyst reuse without significant loss of activity in catalytic cycles, which is a highly interesting prospect for recyclable dye degradation systems.

  4. Fabrication of Sc2O3-magneli phase titanium composite electrode and its application in efficient electrocatalytic degradation of methyl orange

    Science.gov (United States)

    Bai, Hongmei; He, Ping; Chen, Jingchao; Liu, Kaili; Lei, Hong; Dong, Faqin; Zhang, Xingquan; Li, Hong

    2017-04-01

    Sc2O3-magneli phase titanium (Sc2O3-MPT) composite electrode was successfully fabricated via a simple pressing-sintering method and used for electrocatalytic degradation of methyl orange (MO). It was shown that Sc2O3 was successfully composited with MPT. Compared with MPT electrode, Sc2O3-MPT composite electrode had less spherical particles and more pores. Linear scanning voltammetry indicated that Sc2O3-MPT composite electrode presented higher oxygen evolution overpotential than MPT electrode, suggesting that Sc2O3-MPT electrode was much more suitable for the degradation of MO. The electrocatalytic degradation of MO was evaluated under different parameters including current density, temperature, initial pH and electrolysis time. Under the optimal parameters (current density 10 mA cm-2, temperature 25 °C, initial pH 3 and electrolysis time 120 min), the degradation efficiency of MO on Sc2O3-MPT composite electrode reached up to 90.16%. All these results demonstrated that Sc2O3-MPT composite electrode was effective for electrocatalytic degradation of MO and had a great potential application in the treatment of dyes wastewater.

  5. High-efficiency sono-solar-induced degradation of organic dye by the piezophototronic/photocatalytic coupling effect of FeS/ZnO nanoarrays

    Science.gov (United States)

    Guo, Xiao; Fu, Yongming; Hong, Deyi; Yu, Binwei; He, Haoxuan; Wang, Qiang; Xing, Lili; Xue, Xinyu

    2016-09-01

    Highly-efficient sono-solar-induced degradation of organic dye by the piezophototronic/photocatalytic coupling effect of FeS/ZnO nanoarrays was achieved. A steel screen was used as the substrate for supporting FeS/ZnO nanoarrays, and the nanoarrays were vertically and uniformly grown on the substrate via a wet-chemical route. Under ultrasonic and solar irradiation, FeS/ZnO nanoarrays have high sono-photocatalytic activity for degrading methylene blue in water. The photogenerated carriers can be separated by a piezoelectric field and a built-in electric field, resulting in a low recombination rate and high photocatalytic efficiency. The piezophototronic and photocatalytic effects were coupled together. The experimental/theoretical data indicate that this novel wastewater treatment can co-use mechanical and solar energy in nature, and so is a promising technology for environment improvement.

  6. Techniques for Mitigating Thermal Fatigue Degradation, Controlling Efficiency, and Extending Lifetime in a ZnO Thermoelectric Using Grain Size Gradient FGMs

    Science.gov (United States)

    Cramer, Corson L.; Li, Wenjie; Jin, Zhi-He; Wang, Jue; Ma, Kaka; Holland, Troy B.

    2018-01-01

    A functionally graded material (FGM) in terms of grain size gradation is fabricated using zinc oxide (ZnO) with spark plasma sintering and an additive manufacturing technique by diffusion bonding layers of material sintered at different temperatures to achieve a thermoelectric generator (TEG) material that can dissipate heat well and retain high energy conversion efficiency for longer-lasting and comparably efficient TEGs. This FGM is compared to a previously made FGM with continuous grain size gradation. Uniform and graded grain size conditions are modeled for thermoelectric output by using thermoelectric properties of the uniform grain size as well as the varying properties seen in the FGMs. The actual thermoelectric output of the samples is measured and compared to the simulations. The grain size has a large effect on the efficiency and efficiency range. The samples are thermally cycled with a fast heating rate to test the thermal stress robustness and degradation, and the resistance at the highest temperature is measured to indicate degradation from thermal stress. The measured efficiency after cycling shows that the FGMs survive longer lifetime than that with uniform small grains.

  7. Impact of hydrodynamics on pollutant degradation and energy efficiency of VUV/UV and H2O2/UV oxidation processes.

    Science.gov (United States)

    Bagheri, Mehdi; Mohseni, Madjid

    2015-12-01

    The Vacuum-UV/UV process, an incipient catalyst/chemical-free advanced oxidation process (AOP), is potentially a cost-effective solution for the removal of harmful micropollutants from water. Utilizing a novel mechanistic numerical model, this work aimed to establish a thorough understanding of the degradation mechanisms in the VUV/UV process operating under continuous flow conditions, when compared with the widely applied H2O2/UV AOP. Of particular interest was the examination of the impact of flow characteristics (hydrodynamics) on the degradation efficacy of a target micropollutant during the VUV/UV and H2O2/UV AOPs. While hydroxyl radical (OH) oxidation was the dominant degradation pathway in both processes, the degradation efficacy of the VUV/UV process showed much stronger correlation with the extent of mixing in the photoreactor. Under a uniform flow regime, the degradation efficiency of the target pollutant achieved by the H2O2/UV process with 2- and 5 ppm H2O2 was greater than that provided by the VUV/UV process. Nonetheless, introduction of mixing and circulation zones to the VUV/UV reactor resulted in superior performance compared with the H2O2/UV AOP. Based on the electrical energy-per-order (EEO) analysis, incorporation of circulation zones resulted in a reduction of up to 50% in the overall energy cost of the VUV/UV AOP, while the corresponding reduction for the 5-ppm H2O2/UV system was less than 5%. Furthermore, the extent of OH scavenging of natural organic matter (NOM) on energy efficiency of the VUV/UV and H2O2/UV AOPs under continuous flow conditions was assessed using the EEO analysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Determining the degradation efficiency and mechanisms of ethyl violet using HPLC-PDA-ESI-MS and GC-MS

    Directory of Open Access Journals (Sweden)

    Chung Wen-Hsin

    2012-06-01

    Full Text Available Abstract Background The discharge of wastewater that contains high concentrations of reactive dyes is a well-known problem associated with dyestuff activities. In recent years, semiconductor photocatalysis has become more and more attractive and important since it has a great potential to contribute to such environmental problems. One of the most important aspects of environmental photocatalysis is in the selection of semiconductor materials like ZnO and TiO2, which are close to being two of the ideal photocatalysts in several respects. For example, they are relatively inexpensive, and they provide photo-generated holes with high oxidizing power due to their wide band gap energy. In this work, nanostructural ZnO film on the Zn foil of the Alkaline-Manganese Dioxide-Zinc Cell was fabricated to degrade EV dye. The major innovation of this paper is to obtain the degradation mechanism of ethyl violet dyes resulting from the HPLC-PDA-ESI-MS analyses. Results The fabrication of ZnO nanostructures on zinc foils with a simple solution-based corrosion strategy and the synthesis, characterization, application, and implication of Zn would be reported in this study. Other objectives of this research are to identify the reaction intermediates and to understand the detailed degradation mechanism of EV dye, as model compound of triphenylmethane dye, with active Zn metal, by HPLC-ESI-MS and GC-MS. Conclusions ZnO nanostructure/Zn-foils had an excellent potential for future applications on the photocatalytic degradation of the organic dye in the environmental remediation. The intermediates of the degradation process were separated and characterized by the HPLC-PDA-ESI-MS and GC-MS, and twenty-six intermediates were characterized in this study. Based on the variation of the amount of intermediates, possible degradation pathways for the decolorization of dyes are also proposed and discussed.

  9. Training Artisans On-Site

    Directory of Open Access Journals (Sweden)

    Edoghogho Ogbeifun

    2011-09-01

    Full Text Available The decline in apprenticeship in both the public and private sectors, the increasing use of sub-contractors as well as the uncoordinated approach in the informal sector are contributing factors to the shortage of skilled artisans in the construction industry. Artisans training can be introduced and implemented through the adoption of progressive implementation of construction processes commencing work from areas requiring low skill demands to areas of high skill demand. The success of this principle hinges on the collaborative effort of the key project stakeholders. The client should be willing to absorb extra cost and delays in the project; the design and contract documentation should facilitate on-site training, and  the consultant actively guide the contractor and the construction processes to achieve the training objectives. The exploratory research method was adopted in this study and research revealed that this principle was used in a project in the UK and in the development of infrastructure in the tourism industry of South Africa .It is being recommended that the principle be adapted by the public sector for the development of small size infrastructures that can be repeated in many places. This will boost the quality and quantity of artisans, enhance employability, reduce rural urban migration and alleviate poverty.Keywords: Skilled artisans, on-site training, progressive construction processes, project stakeholders, contract documentation. 

  10. An efficient method for the synthesis of photo catalytically active ZnO nanoparticles by a gel-combustion method for the photo-degradation of Caffeine

    Directory of Open Access Journals (Sweden)

    Rajesha Bedre Jagannatha

    2017-01-01

    Full Text Available In this study, Zinc oxide nanoparticles were synthesized by gel-combustion method using a novel bio-fuel tapioca starch pearls, derived from the tubers of Mannihot esculenta, to investigate the photocatalytic degradation of ccaffeine. The ZnO photocatalyst was characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM, and UV-visible spectroscopy. X-ray diffractometry result for the ZnO nanoparticles exhibit normal crystalline phase features. All observed peaks can be indexed to the pure hexagonal wurtzite crystal structures. There are no other impurities in the diffraction peak. In addition, SEM measurement shows that most of the nanoparticles are spongy and spherical in shape and fairly mono dispersed. A significant degradation of the Caffeine was observed when the catalyst was added into the solution even without the UV light exposure. In addition, the photo degradation increaseds with the photocatalyst loading. Besides the photocatalyst loading, the effect of some parameters on the photo degradation efficiency such as initial concentration and pH were also studied.

  11. Sonosynthesis of an Ag/AgBr/Graphene-oxide nanocomposite as a solar photocatalyst for efficient degradation of methyl orange.

    Science.gov (United States)

    Esmaeili, A; Entezari, M H

    2016-03-15

    In this study, a new method has developed for the synthesis of Ag/AgBr/Graphene-oxide (Ag/AgBr/GO) nanocomposite with high adsorption capacity and high photocatalytic activity in degradation of methyl orange (MO). In this method, ultrasound was applied in the synthesis and it was facilitated the process. The samples prepared under ultrasound were shown as Ag/AgBr/GO-U, and the samples under conventional method as Ag/AgBr/GO-C. The results of FT-IR, XRD, Raman, DRS and SEM confirmed the structure of the nanocomposites very well. Ultrasound played a key role in the formation of nanocomposite with smaller size of GO sheets and particles. Different amount of GO was used in the nanocomposite composition and their photocatalytic activities were compared. The MO in solution was completely degraded in 15 min, 30 min, and 45 min with Ag/AgBr/GO-U-1 that contained 1 mg mL(-1) GO, Ag/AgBr/GO-U-0.5 that contained 0.5 mg mL(-1) GO and Ag/AgBr/GO-C-0.5 that contained 0.5 mg mL(-1) GO, respectively. The chemical oxygen demand (COD) measurements displayed a complete mineralization in 30 min for Ag/AgBr/GO-U-0.5. The data obtained from the degradation experiments were fitted to the first-order kinetics and the adsorption obeyed the Langmuir model. The nanocatalyst did not exhibit significant loss of activity even after four cycles of successive uses. To determine the mechanism of photocatalytic degradation of MO, different scavengers were used. Based on the results, the superoxide radical, hydroxyl radical and hole had a key role in the degradation process. The Ag/AgBr/GO-U-1 nanocomposite exhibited the highest photocatalytic activity due to its high adsorption capacity and enhanced charge transfer. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Efficient photocatalytic degradation of ibuprofen in aqueous solution using novel visible-light responsive graphene quantum dot/AgVO{sub 3} nanoribbons

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Zhen-dong [Department of Physics, Tsinghua University, Beijing 100084 (China); Wang, Jia-jun [Shanghai Institute of Applied Radiation, Shanghai University, Shanghai 200444 (China); Wang, Liang, E-mail: wangl@shu.edu.cn [Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 200444 (China); Yang, Xiong-yu; Xu, Gang [Shanghai Institute of Applied Radiation, Shanghai University, Shanghai 200444 (China); Tang, Liang, E-mail: tang1liang@shu.edu.cn [Shanghai Institute of Applied Radiation, Shanghai University, Shanghai 200444 (China)

    2016-07-15

    Highlights: • A novel heterojunction photocatalyst, GQD/AgVO{sub 3} was prepared. • The morphology of GQD/AgVO{sub 3} was well characterized. • Ibuprofen was easily decomposed using GQD/AgVO{sub 3} under visible-light irradiation. • The degradation pathway of ibuprofen was also suggested. - Abstract: Single crystalline, non-toxicity, and long-term stability graphene quantum dots (GQDs) were modified onto the AgVO{sub 3} nanoribbons by a facile hydrothermal and sintering technique which constructs a unique heterojunction photocatalyst. Characterization results indicate that GQDs are well dispersed on the surface of AgVO{sub 3} nanoribbons and GQD/AgVO{sub 3} heterojunctions are formed, which can greatly promote the separation efficiency of photogenerated electron-hole pairs under visible light irradiation. By taking advantage of this feature, the GQD/AgVO{sub 3} heterojunctions exhibit considerable improvement on the photocatalytic activities for the degradation of ibuprofen (IBP) under visible light irradiation as compared to pure AgVO{sub 3}. The photocatalytic activity of GQD/AgVO{sub 3} heterojunctions is relevant with GQD ratio and the optimal activity is obtained at 3 wt% with the highest separation efficiency of photogenerated electron-hole pairs. Integrating the physicochemical and photocatalytic properties, the factors controlling the photocatalytic activity of GQD/AgVO{sub 3} heterojunctions are discussed in detail. Moreover, potential photocatalytic degradation mechanisms of IBP via GQD/AgVO{sub 3} heterojunctions under visible light are proposed.

  13. Photocatalytic degradation of methyl red by TiO2: comparison of the efficiency of immobilized nanoparticles versus conventional suspended catalyst.

    Science.gov (United States)

    Mascolo, G; Comparelli, R; Curri, M L; Lovecchio, G; Lopez, A; Agostiano, A

    2007-04-02

    The photocatalytic efficiency of supported TiO2 nanoparticles (mean size 6 nm), immobilized onto the inner walls of a cylindrical glass photoreactor was compared versus the performance of conventional TiO2 Degussa P25 catalyst. For this purpose the degradation of methyl red dye was used as evaluation test. The obtained results showed that the TiO2 Degussa P25 catalyst is more efficient than the supported nanoparticles. The poorer performance of the nanosized catalyst can be ascribed to the fact that the immobilization procedure turns out, in spite of the extremely high surface to volume ratio, in an overall reduction of active surface area available for target molecule adsorption, due to the low porosity of the supported catalyst layer. The kinetics of the investigated processes were monitored and a study on the reaction products and intermediates was carried out in order to evaluate possible difference in the reaction pathway in presence of immobilized nanoparticles versus suspended catalyst. The results demonstrate that the mechanisms of parent dye degradation in presence of supported TiO2 nanoparticles are the same as those occurring in presence of TiO2 Degussa P25 catalyst. The present work describe the results obtained on the feasibility of scaling up the colloidal nanocrystal-based photocatalysis experiment: the comparison with a well standardized degradation method performed with a known material can allow a realistic evaluation of the advantages and the limits of the investigated nanoparticle towards the ultimate technology transfer.

  14. Nanocrystalline ZnO doped lanthanide oxide: An efficient photocatalyst for the degradation of diesel pollutant in seawater under visible light irradiation

    Science.gov (United States)

    Yu, Xiaocai; Ji, Qiuyi; Zhang, Jian; Nie, Zhiwei; Liu, Jinghua; Wang, Liping

    2017-08-01

    In this study, a ZnO doped Er2O3 photocatalyst is employed to degrade diesel pollutant in seawater under visible light irradiation. The photocatalyst was prepared by a precipitation method and was characterized by SEM and XRD analysis. The experimental results proved that the nanocrystalline photocatalysts were highly active in the visible region. The photocatalytic degradation efficiency of diesel was analysed by various experimental parameters namely dosage, doping ratio, initial concentration of diesel, pH value, concentration of H2O2 and illumination time. The degradation of diesel pollution in seawater was optimized by orthogonal experiment. According to the results, the removal rate of diesel is less than 30 % without any catalysts (only evaporation). The best effect exists when the dose of catalysts was 0.6 g/L, doping ratio of catalysts was 10%, initial concentration of diesel was 0.2 g/L, pH value was 8, concentration of H2O2 was 10 mg/L, illumination time was 1 h. The removal rate of diesel can reach 99.38 %. This study would make ZnO utilize sunlight more efficiently and accelerate the practical application of photocatalytic technology in organic pollutants treatment region.

  15. Ag loaded WO{sub 3} nanoplates for efficient photocatalytic degradation of sulfanilamide and their bactericidal effect under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Wenyu [School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Nanyang Environment and Water Research Institute (NEWRI), Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141 (Singapore); Liu, Jincheng, E-mail: JCLIU@ntu.edu.sg [School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Current address: Faculty of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510009 (China); Yu, Shuyan; Zhou, Yan [School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Nanyang Environment and Water Research Institute (NEWRI), Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore 637141 (Singapore); Yan, Xiaoli, E-mail: XLYAN@ntu.edu.sg [School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Current address: Environmental and Water Technology Centre of Innovation, Ngee Ann Polytechnic, 535 Clementi Road, Singapore 599489 (Singapore)

    2016-11-15

    Highlights: • WO{sub 3}/Ag heterogeneous composites were fabricated with simply photo-reduction method. • Property changes due to Ag loading were systematically studied. • WO{sub 3}/Ag composites efficiently degraded sulfanilamide under visible light irradiation. • WO{sub 3}/Ag composites exhibited bactericidal effectS under visible light irradiation. - Abstract: Sulfonamides (SAs) are extensively used antibiotics and their residues in the water bodies propose potential threat to the public. In this study, degradation efficiency of sulfanilamide (SAM), which is the precursor of SAs, using WO{sub 3} nanoplates and their Ag heterogeneous as photocatalysts was investigated. WO{sub 3} nanoplates with uniform size were synthesized by a facile one step hydrothermal method. Different amount of Ag nanoparticles (Ag NPs) were loaded onto WO{sub 3} nanoplates using a photo-reduction method to generate WO{sub 3}/Ag composites. The physio-chemical properties of synthesized nanomaterials were systematically characterized. Photodegradation of SAM by WO{sub 3} and WO{sub 3}/Ag composites was conducted under visible light irradiation. The results show that WO{sub 3}/Ag composites performed much better than pure WO{sub 3} where the highest removal rate was 96.2% in 5 h. Ag as excellent antibacterial agent also endows certain antibacterial efficiency to WO{sub 3}, and 100% removal efficiency against Escherichia Coli and Bacillus subtilis could be achieved in 2 h under visible light irradiation for all three WO{sub 3}/Ag composites synthesized. The improved performance in terms of SAM degradation and antibacterial activity of WO{sub 3}/Ag can be attributed to the improved electron-hole pair separation rate where Ag NPs act as effective electron trapper during the photocatalytic process.

  16. On Site Inspection Radionuclide Measurements

    Science.gov (United States)

    Hayes, J. C.; Haas, D.; Milbrath, B. D.; Miley, H.; Seifert, C. E.

    2013-12-01

    The goal of an On Site Inspection for the CTBT is the clarification of the nature of a triggering event - probably a seismic signal. After a request for inspection is made and accepted, an inspection team proceeds to the environs of the triggering event and uses visual, seismic, radiological, or other location-finding methods to narrow down the search area. Survey, environmental sampling, and field-lab measurement methods then are used to try to collect definitive facts to support decisions of an Executive Council of the Treaty. Refining and optimizing the science methods for practical survey, sampling, and measurement requires reasonable measurement objectives to be stated. The authors will present a few scenario-dependant objectives such that the field approaches and equipment specifications could follow.

  17. Specific ion effect on the surface properties of Ag/reduced graphene oxide nanocomposite and its influence on photocatalytic efficiency towards azo dye degradation

    Science.gov (United States)

    Borthakur, Priyakshree; Boruah, Purna K.; Hussain, Najrul; Silla, Yumnam; Das, Manash R.

    2017-11-01

    The surface property of a catalyst is influenced by the presence of different inorganic ions as well as pH of the medium. Ag/reduced graphene oxide (Ag/rGO) nanocomposite was synthesized by adopting simple solution chemistry technique using simple ultrasonication process. The influence of the specific anions like Cl-, Br-, NO3-, SO42-, CH3COO- as well as cations like Na+, NH4+, Mg2+ and Ca2+ ions on the surface charge (zeta potential) of the nanocomposite and their effect on the photocatalytic degradation efficiency towards azo dye degradation in aqueous medium was studied. We found that the catalytic property of the nanocomposite is significantly influenced by its surface property which is a function of pH of the medium and the different inorganic ions present in the system.

  18. Hybrid copper doped titania/polythiophene nanorods as efficient visible light-driven photocatalyst for degradation of organic pollutants

    Directory of Open Access Journals (Sweden)

    M. Ravi Chandra

    2017-12-01

    Full Text Available The hybrid Cu–TiO2/polythiophene nanorods (HNRs were prepared by modified sol–gel technique at low temperature through oxidative polymerization of thiophene. The prepared HNRs and Cu–TiO2 nanorods without polymer (CTNRs were characterized by using XRD, TEM, IR, UV–vis DRS and XPS. IR, XPS and XRD confirm polythiophene (PTh covered Cu–TiO2 nanorod in hybrid with rutile phase without affecting the crystal form of TiO2. TEM analysis reveals the shape and morphology of CTNRs and HNRs. TEM images of HNRs show that the metal oxide has nanorods like shape with lengths and diameters of about 35–60 and 15–25 nm respectively. From UV–visible DRS spectra, HNRs exhibit a broad and strong absorption in visible range, indicating that the incorporation of PTh onto the surface of Cu–TiO2 nanorod in hybrid can extend the photo response range of TiO2. The photocatalytic activity of HNRs shows higher degradation when compared with CTNRs under visible light irradiation by degradation of Rhodamine B (RhB and Orange G (OG. There is no degradation of PTh was observed under visible light irradiation till five runs which is examined from photocatalytic activity, which indicates stability and reusability of photocatalyst.

  19. One-pot synthesis of ultrathin manganese dioxide nanosheets and their efficient oxidative degradation of Rhodamine B

    Science.gov (United States)

    Sun, Hang; Xu, Kongliang; Huang, Majia; Shang, Yinxing; She, Ping; Yin, Shengyan; Liu, Zhenning

    2015-12-01

    Ultrathin manganese dioxide (MnO2) nanosheets have been synthesized in aqueous solution by a facile one-step method. MnO2 nanosheets show a typical 2D lamellar morphology, possessing an average lateral dimension of 100-300 nm, and a typical thickness of 3.1-7.5 nm, corresponding to 4-10 layers of δ-MnO2. The resultant MnO2 nanosheets have been demonstrated to possess superior oxidative degradation ability to Rhodamine B (RhB) by investigating the decomposition rate and comparing the results with the commercial MnO2 powder. Typically, ultrathin MnO2 nanosheets have shown a high oxidation degradation performance of RhB solution (97.9% removed within 30 min) in acid solution (pH 2.0), which can be attributed to special lamellar morphology and the large surface area of the layered MnO2 nanosheets. It is believed that such a convenient approach for the cost-effective and environmentally friendly synthesis of ultrathin MnO2 nanosheets holds great promise for the degradation of complex and various dye wastewater in practical application.

  20. The interplay of Hrd3 and the molecular chaperone system ensures efficient degradation of malfolded secretory proteins

    Science.gov (United States)

    Mehnert, Martin; Sommermeyer, Franziska; Berger, Maren; Kumar Lakshmipathy, Sathish; Gauss, Robert; Aebi, Markus; Jarosch, Ernst; Sommer, Thomas

    2015-01-01

    Misfolded proteins of the secretory pathway are extracted from the endoplasmic reticulum (ER), polyubiquitylated by a protein complex termed the Hmg-CoA reductase degradation ligase (HRD-ligase), and degraded by cytosolic 26S proteasomes. This process is termed ER-associated protein degradation (ERAD). We previously showed that the membrane protein Der1, which is a subunit of the HRD-ligase, is involved in the export of aberrant polypeptides from the ER. Unexpectedly, we also uncovered a close spatial proximity of Der1 and the substrate receptor Hrd3 in the ER lumen. We report here on a mutant Hrd3KR that is selectively defective for ERAD of soluble proteins. Hrd3KR displays subtle structural changes that affect its positioning toward Der1. Furthermore, increased quantities of the ER-resident Hsp70-type chaperone Kar2 and the Hsp40-type cochaperone Scj1 bind to Hrd3KR. Of note, deletion of SCJ1 impairs ERAD of model substrates and causes the accumulation of client proteins at Hrd3. Our data imply a function of Scj1 in the removal of malfolded proteins from the receptor Hrd3, which facilitates their delivery to downstream-acting components like Der1. PMID:25428985

  1. Comparison of efficiency degradation in polycrystalline-Si and CdTe thin-film PV modules via accelerated lifecycle testing

    Science.gov (United States)

    Lai, T.; Potter, B. G.; Simmons-Potter, K.

    2017-08-01

    Thin-film solar cells normally have the shortest energy payback time due to their simpler mass-production process compared to polycrystalline-Si photovoltaic (PV) modules, despite the fact that crystalline-Si-based technology typically has a longer total lifetime and a higher initial power conversion efficiency. For both types of modules, significant aging occurs during the first two years of usage with slower long-term aging over the module lifetime. The PV lifetime and the return-on-investment for local PV system installations rely on long-term device performance. Understanding the efficiency degradation behavior under a given set of environmental conditions is, therefore, a primary goal for experimental research and economic analysis. In the present work, in-situ measurements of key electrical characteristics (J, V, Pmax, etc.) in polycrystalline-Si and CdTe thin-film PV modules have been analyzed. The modules were subjected to identical environmental conditions, representative of southern Arizona, in a full-scale, industrial-standard, environmental degradation chamber, equipped with a single-sun irradiance source, temperature, and humidity controls, and operating an accelerated lifecycle test (ALT) sequence. Initial results highlight differences in module performance with environmental conditions, including temperature de-rating effects, for the two technologies. Notably, the thin-film CdTe PV module was shown to be approximately 15% less sensitive to ambient temperature variation. After exposure to a seven-month equivalent compressed night-day weather cycling regimen the efficiency degradation rates of both PV technology types were obtained and will be discussed.

  2. Newly isolated Penicillium oxalicum A592-4B secretes enzymes that degrade milled rice straw with high efficiency.

    Science.gov (United States)

    Aoyama, Akihisa; Kurane, Ryuichiro; Matsuura, Akira; Nagai, Kazuo

    2015-01-01

    An enzyme producing micro-organism, which can directly saccharify rice straw that has only been crushed without undergoing the current acid or alkaline pretreatment, was found. From the homology with the ITS, 28S rDNA sequence, the strain named A592-4B was identified as Penicillium oxalicum. Activities of the A592-4B enzymes and commercial enzyme preparations were compared by Novozymes Cellic CTec2 and Genencore GC220. In the present experimental condition, activity of A592-4B enzymes was 2.6 times higher than that of CTec2 for degrading milled rice straw. Furthermore, even when a quarter amount of A592-4B enzyme was applied to the rice straw, the conversion rate was still higher than that by CTec2. By utilizing A592-4B enzymes, improved lignocellulose degradation yields can be achieved without pre-treatment of the substrates; thus, contributing to cost reduction as well as reducing environmental burden.

  3. Nanocrystalline ZnO doped lanthanide oxide: An efficient photocatalyst for the degradation of malachite green dye under visible light irradiation

    Directory of Open Access Journals (Sweden)

    G.A. Suganya Josephine

    2015-09-01

    Full Text Available Visible light induced semiconductor photocatalysis has received a great attention in recent years due to the contamination of water bodies. In the present study, we have reported the photo catalytic degradation of a toxic organic dye, malachite green using a ZnO doped Dy2O3 photo catalyst under visible light irradiation. The nanocrystalline photocatalyst was prepared by a precipitation method employing the respective nitrates and sodium carbonate as precursors and were characterized by FT-IR, XRD, UV–Vis DRS, FE-SEM and AFM analysis. The experimental results proved that the prepared photo catalysts were crystalline, nanosized and highly active in the visible region. UV–Vis DRS results suggested that the band gap was 3.1 eV for the prepared photo catalyst. The photodegradation efficiency of malachite green was analysed by various experimental parameters namely pH, catalyst dosage, variation of substrate concentration and effect of electrolyte addition. The photo degradation process followed a pseudo first order kinetics and was continuously monitored by UV–Visible spectrophotometer. The degradation of malachite green was above 99% within 1 h of visible light irradiation employing the doped photocatalyst, whereas pristine metal oxide possessed only 67% and pristine lanthanide oxide possessed activity which was only due to photolysis. A plausible mechanism for the generation of OH radicals and the pathway for MG dye degradation has been proposed in this study. The experimental results clearly show that nanocrystalline semiconductor doped lanthanide oxides are highly active under visible light irradiations and may find wider applications in environmental remediation technologies.

  4. Ni/Co/Ti layered double hydroxide for highly efficient photocatalytic degradation of Rhodamine B and Acid Red G: a comparative study.

    Science.gov (United States)

    Chowdhury, Priyadarshi Roy; Bhattacharyya, Krishna G

    2017-06-14

    Optically responsive, luminescent Ni/Co/Ti layered double hydroxide (LDH), synthesized by a single step hydrothermal route, exhibits highly efficient photodegradation of cationic and anionic dyes, Rhodamine B (∼99.8%) and Acid Red G (∼99.6%) respectively, better than that of commercial catalysts like NiO, CoO and TiO 2 . The LDH has been characterized by using XRD, XPS, PL, TRES, EIS, TEM, SEM-EDX, AFM, UV-visible DRS, N 2 -sorption desorption, ξ-potential, FT-IR and TG techniques. The characterized results indicate that the LDH possesses hexagonal morphology, a high surface area, a narrow band gap, defect states and oxygen vacancies within its layered framework. The degradations follow the e - -h + hopping pattern and dye-photosensitized mechanistic pathways. The active species generated during photocatalysis have been evaluated using ESR, terephthalic acid fluorescence probe and indirect radical-hole trapping experiments. The colourless end products were investigated by GC-MS and reaction mechanisms have been established for the degradation of the dyes to less toxic and more eco-friendly molecules than their parent analogues. Dye mineralization studies (performed using a TOC analyser) and closure of carbon mass balance experiments quantified the amount of carbon entering and leaving the reaction systems. Reaction mechanisms have been proposed on the basis of the asymmetric cleavage of the dyes. The LDH demonstrated its remarkable efficiency in the field of waste water treatment.

  5. Crude oil degradation efficiency of a recombinant Acinetobacter baumannii strain and its survival in crude oil-contaminated soil microcosm.

    Science.gov (United States)

    Mishra, Sanjeet; Sarma, Priyangshu M; Lal, Banwari

    2004-06-15

    A hydrocarbon degrading Acinetobacter baumannii S30 strain, isolated from crude oil-contaminated soil, was inserted with the lux gene from the luciferase gene cassette luxCDABE. Soil microcosms were designed to study the degradation efficacy for total petroleum hydrocarbon (TPH) of crude oil by lux-tagged A. baumannii S30 pJES. Bioaugmentation of a TPH-contaminated microcosm with A baumannii S30 pJES showed that TPH levels were reduced from 89.3 to 53.9 g/kg soil in 90 days. Biodegradation of TPH by A baumannii S30 pJES was also monitored in shake flask conditions, which showed a reduction of initial TPH levels by over 50% at the end of 120 h. A lux-PCR-based approach along with the standard dilution plating with selective antibiotics was successfully utilized to monitor the survivability of the lux-tagged strain A. baumannii S30 pJES in soil microcosms and stability of the lux insert in the host strain A. baumannii S30. The selective plating technique indicated the population of A. baumannii S30 pJES to be 6.5+/-0.13 x 10(8) CFU/g at day zero (just after bioaugmentation) and 2.09+/-0.08 x 10(8) CFU/g of soil after 90 days of incubation. lux-PCR confirmed the stability of the insert in all the randomly selected colonies of A. baumannii strains from the antibiotic plates. The lux insert was stable after 50 generations in Luria Bertini broth and storage at -70 degrees C as glycerol stocks for over a year. These results revealed that the lux insert was stable and lux-tagged A. baumannii S30 strain could survive in a TPH-contaminated soil microcosm and could degrade TPH in the soil microcosm conditions. It can be used as an effective marker to monitor the survival of augmented strains at a bioremediation site.

  6. Bifunctional anti-huntingtin proteasome-directed intrabodies mediate efficient degradation of mutant huntingtin exon 1 protein fragments.

    Directory of Open Access Journals (Sweden)

    David C Butler

    Full Text Available Huntington's disease (HD is a fatal autosomal dominant neurodegenerative disorder caused by a trinucleotide (CAG(n repeat expansion in the coding sequence of the huntingtin gene, and an expanded polyglutamine (>37Q tract in the protein. This results in misfolding and accumulation of huntingtin protein (htt, formation of neuronal intranuclear and cytoplasmic inclusions, and neuronal dysfunction/degeneration. Single-chain Fv antibodies (scFvs, expressed as intrabodies that bind htt and prevent aggregation, show promise as immunotherapeutics for HD. Intrastriatal delivery of anti-N-terminal htt scFv-C4 using an adeno-associated virus vector (AAV2/1 significantly reduces the size and number of aggregates in HDR6/1 transgenic mice; however, this protective effect diminishes with age and time after injection. We therefore explored enhancing intrabody efficacy via fusions to heterologous functional domains. Proteins containing a PEST motif are often targeted for proteasomal degradation and generally have a short half life. In ST14A cells, fusion of the C-terminal PEST region of mouse ornithine decarboxylase (mODC to scFv-C4 reduces htt exon 1 protein fragments with 72 glutamine repeats (httex1-72Q by ~80-90% when compared to scFv-C4 alone. Proteasomal targeting was verified by either scrambling the mODC-PEST motif, or via proteasomal inhibition with epoxomicin. For these constructs, the proteasomal degradation of the scFv intrabody proteins themselves was reduced<25% by the addition of the mODC-PEST motif, with or without antigens. The remaining intrabody levels were amply sufficient to target N-terminal httex1-72Q protein fragment turnover. Critically, scFv-C4-PEST prevents aggregation and toxicity of httex1-72Q fragments at significantly lower doses than scFv-C4. Fusion of the mODC-PEST motif to intrabodies is a valuable general approach to specifically target toxic antigens to the proteasome for degradation.

  7. Influence of the anode materials on the electrochemical oxidation efficiency.Aplication to oxidative degradation of the pharmaceutical amoxicillin

    OpenAIRE

    Rodrigo Rodrigo, Manuel Andrés; Sopaj, Flamur; Oturan, Nihal; Podvorica, Fetah I.; Pinson, Jean; Oturan, Mehmet

    2015-01-01

    In this study, the electro-oxidation capacities of several electrode materials such as carbon-felt, carbon-fiber, carbon-graphite, platinum, lead dioxide, DSA (Dimensionally Stable Anode), (Ti/RuO2-IrO2), and BDD (Boron-Doped Diamond) were tested for the destruction of the antibiotic amoxicillin (AMX) in aqueous medium. BDD anode was more efficient than DSA to oxidize and mineralize totally AMX in water. Moreover, for BDD electrode we obtained very high electrolysis efficiency for the initial...

  8. The effect of polysaccharide-degrading wine yeast transformants on the efficiency of wine processing and wine flavour.

    Science.gov (United States)

    Louw, C; La Grange, D; Pretorius, I S; van Rensburg, P

    2006-10-01

    Commercial polysaccharase preparations are applied to winemaking to improve wine processing and quality. Expression of polysaccharase-encoding genes in Saccharomyces cerevisiae allows for the recombinant strains to degrade polysaccharides that traditional commercial yeast strains cannot. In this study, we constructed recombinant wine yeast strains that were able to degrade the problem-causing grape polysaccharides, glucan and xylan, by separately integrating the Trichoderma reesei XYN2 xylanase gene construct and the Butyrivibrio fibrisolvens END1 glucanase gene cassette into the genome of the commercial wine yeast strain S. cerevisiae VIN13. These genes were also combined in S. cerevisiae VIN13 under the control of different promoters. The strains that were constructed were compared under winemaking conditions with each other and with a recombinant wine yeast strain expressing the endo-beta-1,4-glucanase gene cassette (END1) from B. fibrisolvens and the endo-beta-1,4-xylanase gene cassette (XYN4) from Aspergillus niger, a recombinant strain expressing the pectate lyase gene cassette (PEL5) from Erwinia chrysanthemi and the polygalacturonase-encoding gene cassette (PEH1) from Erwinia carotovora. Wine was made with the recombinant strains using different grape cultivars. Fermentations with the recombinant VIN13 strains resulted in significant increases in free-flow wine when Ruby Cabernet must was fermented. After 6 months of bottle ageing significant differences in colour intensity and colour stability could be detected in Pinot Noir and Ruby Cabernet wines fermented with different recombinant strains. After this period the volatile composition of Muscat d'Alexandria, Ruby Cabernet and Pinot Noir wines fermented with different recombinant strains also showed significant differences. The Pinot Noir wines were also sensorial evaluated and the tasting panel preferred the wines fermented with the recombinant strains.

  9. Sn-doped ZnO nanopetal networks for efficient photocatalytic degradation of dye and gas sensing applications

    Science.gov (United States)

    Bhatia, Sonik; Verma, Neha; Bedi, R. K.

    2017-06-01

    Nowadays, tremendous increase in environmental issue is an alarming threat to the ecosystem. This paper reports, rapid synthesis and characterization for tin doped ZnO nanoparticles prepared by simple combustion method and doctor blade technique. The prepared nanoparticles were characterized by several techniques in terms of their morphological, structural, compositional, optical, photocatalytic and gas sensing properties. These detailed characterization confirmed that all the synthesized nanoparticles are well crystalline and having good optoelectronic properties. Herein, different concentrations of Sn (0.5 at. wt%, 1.0 at. wt%, 2.0 at. wt%, 3.0 at. wt%) were used as dopants (SZ1-SZ4). The morphology of synthesized technique confirmed that the petal-shaped nanoparticles has high surface area and are well crystalline. In order to develop smart and functional nano-device, the prepared powder was coated on glass substrate by doctor blade technique and fabricated device was sensed for ethanol and acetone gas at different operating temperatures (300-500̊C). It is noteworthy that morphology of the nanoparticles of the sensitive layer is maintained after different concentration of Sn. High sensitivity is the main cause of high surface area and tin doping. PL intensity near 598 nm of SZ3 is greater than other Sn-doped ZnO which indicates more oxygen vacancies of SZ3 is responsible for enhanced gas sensitivity and photocatalytic activity. The sensing performance showed 5% volume of ethanol and acetone and gases could be detected with sensitivity of 86.80% and 84.40% respectively. The mechanism for the improvement in the sensing properties can be explained with the surface adsorption theory. Sn-ZnO was used as photocatalyst for degradation of DR-31 dye. Optimum concentration of prepared nanoparticles (2.0 at. wt%) exhibits complete degradation of dye only in 60 min under UV irradiation.

  10. Design of binary SnO2-CuO nanocomposite for efficient photocatalytic degradation of malachite green dye

    Science.gov (United States)

    Kumar, Aniket; Rout, Lipeeka; Achary, L. Satish Kumar; Mohanty, Anurag; Marpally, Jyoshna; Chand, Pradyumna Kumar; Dash, Priyabrat

    2016-04-01

    Semiconductor mediated photocatalysis has got enormous consideration as it has shown immense potential in addressing the overall energy and environmental issues. To overcome the earlier drawbacks concerning quick charge recombination and limited visible-light absorption of semiconductor photocatalysts, numerous methods have been produced in the past couple of decades and the most broadly utilized one is to develop the photocatalytic heterojunctions. In our work, a series of SnO2-CuO nanocomposites of different compositions were synthesized by a combustion method and have been investigated in detail by various characterization techniques, such as wide angle X-ray diffraction (XRD), UV-vis spectroscopy, transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). The results revealed that the crystal structure and optical properties of the nanocomposites were almost same for all the compositions. FE-SEM images showed that the shape of SnO2-CuO was spherical in nature and the 1: 1 Sn/Cu sample had a well-proportioned morphology. The malachite green dye was used for the photocatalytic studies in a photoreactor and monitored with a UV-visible spectrometer for different composition ratio of metal (Sn: Cu) such as 1:1, 1:2, 2:1, 1:0.5 and 0.5:1. The 1:1 ratio nanocomposite showed excellent photocatalytic degradation of 96 % compared to pure SnO2 and CuO. The mechanism of degradation and charge separation ability of the nanocomposite are also explored using photocurrent measurement study.

  11. TUNGSTOPHOSPHORIC ACID HETEROGENIZED ONTO NH4ZSM5 AS AN EFFICIENT AND RECYCLABLE CATALYST FOR THE PHOTOCATALYTIC DEGRADATION OF DYES

    Directory of Open Access Journals (Sweden)

    Candelaria Leal Marchena

    2015-05-01

    Full Text Available Materials based on tungstophosphoric acid (TPA immobilized on NH4ZSM5 zeolite were prepared by wet impregnation of the zeolite matrix with TPA aqueous solutions. Their concentration was varied in order to obtain TPA contents of 5%, 10%, 20%, and 30% w/w in the solid. The materials were characterized by N2 adsorption-desorption isotherms, XRD, FT-IR, 31P MAS-NMR, TGA-DSC, DRS-UV-Vis, and the acidic behavior was studied by potentiometric titration with n-butylamine. The BET surface area (SBET decreased when the TPA content was raised as a result of zeolite pore blocking. The X-ray diffraction patterns of the solids modified with TPA only presented the characteristic peaks of NH4ZSM5 zeolites, and an additional set of peaks assigned to the presence of (NH43PW12O40. According to the Fourier transform infrared and 31P magic angle spinning-nuclear magnetic resonance spectra, the main species present in the samples was the [PW12O40]3- anion, which was partially transformed into the [P2W21O71]6- anion during the synthesis and drying steps. The thermal stability of the NH4ZSM5TPA materials was similar to that of their parent zeolites. Moreover, the samples with the highest TPA content exhibited band gap energy values similar to those reported for TiO2. The immobilization of TPA on NH4ZSM5 zeolite allowed the obtention of catalysts with high photocatalytic activity in the degradation of methyl orange dye (MO in water, at 25 ºC. These can be reused at least three times without any significant decrease in degree of degradation.

  12. Photocatalytic degradation of organic compounds by Au-TiO2/sepiolite composites as the highly efficient catalysts

    Science.gov (United States)

    Zhang, Dongfang

    2014-12-01

    Photocatalytic oxidation of methyl orange (MO) and Congo red (CR) as typical model organic contaminants was investigated in aqueous solution within a cooperating Au/TiO2/sepiolite heterostructure system under UV light irradiation. The Au/TiO2/sepiolite composites with a single-crystalline (anatase) framework was synthesized by a facile sol-gel method using titanium tetrachloride as a TiO2 precursor and depositing metal Au on the surface of TiO2 nanostructures via a facile chemical reduction process. The crystal structure, surface area, light adsorption and the photoinduced charge separation rate of the photocatalyst prepared were characterized in detail. As compared with the pristine TiO2, the Au/TiO2/sepiolite hybrid material exhibited good photocatalytic efficiency (90%) for the UV-light photooxidation of methyl orange, which is four-fold of that of reference TiO2. In addition, Au/TiO2/sepiolite hybrid material also shows a good photodegradation performance toward Congo red removal. The highly efficient photocatalytic activity is associated with the strong adsorption ability of sepiolite for aromatic dye molecules, fast photogenerated charge separation due to the formation of Schottky junction between TiO2 and metallic Au. This work suggests that the combination of the excellent adsorption properties of sepiolite and the efficient separation effect of noble metallic nanoparticles provides a versatile strategy for the synthesis of novel and highly efficient photocatalysts.

  13. Protein synthesis and degradation gene SNPs related to feed intake, feed efficiency, growth, and ultrasound carcass traits in Nellore cattle.

    Science.gov (United States)

    Gomes, R C; Silva, S L; Carvalho, M E; Rezende, F M; Pinto, L F B; Santana, M H A; Stella, T R; Meirelles, F V; Rossi Júnior, P; Leme, P R; Ferraz, J B S

    2013-08-12

    We looked for possible associations of SNPs in genes related to protein turnover, with growth, feed efficiency and carcass traits in feedlot Nellore cattle. Purebred Nellore bulls and steers (N = 290; 378 ± 42 kg body weight, 23 months ± 42 days old) were evaluated for daily feed intake, body weight gain (BWG), gross feed efficiency, feed conversion ratio, partial efficiency of growth, residual feed intake (RFI), ultrasound backfat, rump fat, and ribeye area. Genotypes were obtained for SNPs in the growth hormone receptor (GHR-1 and GHR-2); calpain (CAPN4751); calpastatin (UoGCAST); ubiquitin-conjugating enzyme 2I (UBE2I-1 and UBE2I-2); R3H domain containing 1 (R3HDM1-1, -2, -3, and -4), ring finger protein 19 (RNF19); proteasome 26S subunit, non-ATPase, 13 (PSMD13); ribosomal protein, large, P2 (RPLP2); and isoleucine-tRNA synthetase 2, mitochondrial (IARS2) genes. Allelic substitution, additive and dominant effects were tested and molecular breeding values were computed. CAPN4751, GHR-1 and -2, IARS2, R3HDM1-4, and UoGCAST were found to be normally segregating polymorphisms. Additive and dominance effects were observed on BWG, feed efficiency and carcass traits, although dominant effects predominated. Significant allelic substitution effects were observed for CAPN4751, GHR-1 and -2, and UoGCAST on BWG, gross feed efficiency, RFI, and carcass traits, under single- or multiple-marker analyses. Correlations between molecular breeding values and phenotypes were low, excepted for RFI, based on allelic substitution estimates obtained by stepwise linear regression. We conclude that SNPs in genes related to protein turnover are related to economically important traits in Nellore cattle.

  14. On-Site School Library Automation: Automation Anywhere with Laptops.

    Science.gov (United States)

    Gunn, Holly; Oxner, June

    2000-01-01

    Four years after the Halifax Regional School Board was formed through amalgamation, over 75% of its school libraries were automated. On-site automation with laptops was a quicker, more efficient way of automating than sending a shelf list to the Technical Services Department. The Eastern Shore School Library Automation Project was a successful…

  15. Sn-doped ZnO nanopetal networks for efficient photocatalytic degradation of dye and gas sensing applications

    Energy Technology Data Exchange (ETDEWEB)

    Bhatia, Sonik, E-mail: sonikbhatia@gmail.com [Department of Physics, Kanya Maha Vidyalaya, Vidyalaya Marg, Jalandhar, 144004 (India); Verma, Neha [Department of Physics, Kanya Maha Vidyalaya, Vidyalaya Marg, Jalandhar, 144004 (India); Bedi, R.K. [Satyam Institute of Engineering and Technology, Amritsar, 143107, Punjab (India)

    2017-06-15

    sensitivity and photocatalytic activity. The sensing performance showed 5% volume of ethanol and acetone and gases could be detected with sensitivity of 86.80% and 84.40% respectively. The mechanism for the improvement in the sensing properties can be explained with the surface adsorption theory. Sn–ZnO was used as photocatalyst for degradation of DR-31 dye. Optimum concentration of prepared nanoparticles (2.0 at. wt%) exhibits complete degradation of dye only in 60 min under UV irradiation.

  16. Self-assembly of ultrathin Cu2MoS4 nanobelts for highly efficient visible light-driven degradation of methyl orange

    Science.gov (United States)

    Zhang, Ke; Chen, Wenxing; Lin, Yunxiang; Chen, Haiping; Haleem, Yasir A.; Wu, Chuanqiang; Ye, Fei; Wang, Tianxing; Song, Li

    2015-10-01

    We demonstrate ultrathin self-assembled Cu2MoS4 nanobelts synthesized by using Cu2O as the starting sacrificial template via a hydrothermal method. The nanobelts exhibit strong light absorption over a broad wavelength spectrum, suggesting their potential application as photocatalysts. The photocatalytic activity of nanobelts is evaluated by the degradation of Methyl Orange (MO) dye under visible light irradiation. Notably, the nanobelts can completely degrade 100 mL of 15 mg mL-1 MO in 20 minutes with excellent recycling and structural stability, suggesting their excellent photocatalytic performance. In comparison with a sheet-like sample, the high efficiency of the self-assembled Cu2MoS4 nanobelts is attributed to a high surface area and a unique band gap, agreeing with the nitrogen adsorption analysis and photoluminescence spectra. This study offers a self-assembled synthetic route to create new multifunctional nanoarchitectures composed of atomic layers, and thus may open a window for greatly extending potential applications in water pollution treatment, photocatalytic water-splitting, solar cells and other related fields.We demonstrate ultrathin self-assembled Cu2MoS4 nanobelts synthesized by using Cu2O as the starting sacrificial template via a hydrothermal method. The nanobelts exhibit strong light absorption over a broad wavelength spectrum, suggesting their potential application as photocatalysts. The photocatalytic activity of nanobelts is evaluated by the degradation of Methyl Orange (MO) dye under visible light irradiation. Notably, the nanobelts can completely degrade 100 mL of 15 mg mL-1 MO in 20 minutes with excellent recycling and structural stability, suggesting their excellent photocatalytic performance. In comparison with a sheet-like sample, the high efficiency of the self-assembled Cu2MoS4 nanobelts is attributed to a high surface area and a unique band gap, agreeing with the nitrogen adsorption analysis and photoluminescence spectra. This study

  17. Copper-promoted circumneutral activation of H2O2 by magnetic CuFe2O4 spinel nanoparticles: Mechanism, stoichiometric efficiency, and pathway of degrading sulfanilamide.

    Science.gov (United States)

    Feng, Yong; Liao, Changzhong; Shih, Kaimin

    2016-07-01

    To evaluate the heterogeneous degradation of sulfanilamide by external energy-free Fenton-like reactions, magnetic CuFe2O4 spinel nanoparticles (NPs) were synthesized and used as catalysts for activation of hydrogen peroxide (H2O2). The physicochemical properties of the CuFe2O4 NPs were characterized with several techniques, including X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and magnetometry. In the catalytic experiments, CuFe2O4 NPs/H2O2 oxidation showed the best degradation performance in the circumneutral conditions that resulted from the presence of Cu(II) on the surface of the CuFe2O4 NPs. The surface area-normalized pseudo-first-order rate constants were calculated as 2.60 × 10(-2) L m(-1) min(-1), 2.58 × 10(-3) L m(-1) min(-1), 1.92 × 10(-3) L m(-1) min(-1), and 7.30 × 10(-4) L m(-1) min(-1) for CuO, CuFe2O4 NPs, Fe3O4, and α-Fe2O3 catalysts, respectively. Thus, solid state Cu(II) was more reactive and efficient than Fe(III) in the circumneutral activation of H2O2; this finding was further supported by the results regarding the stoichiometric efficiency of H2O2. The effects of experimental parameters such as the oxidant dosage and catalyst loading were investigated. The mechanism for H2O2 activation on the spinel surface was explored and could be explained by the solid redox cycles of Fe(II)/Fe(III) and Cu(II)/Cu(I). Based on the products detected, a degradation pathway via the CS bond cleavage is proposed for the degradation of sulfanilamide. The findings of this study suggest that copper can be used as a doping metal to improve the reactivity and expand the effective pH range of iron oxides. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Nano-Titania Photocatalyst Loaded on W-MCM-41 Support and Its Highly Efficient Degradation of Methylene Blue

    Science.gov (United States)

    Shankar, H.; Saravanan, R.; Narayanan, V.; Stephen, A.

    2011-07-01

    Most of the azo dyes produced in textile, printing, paper manufacturing, pulp processing and pharmaceutical industries contain different organic contaminants. These dyes can enter the body through ingestion and the high content in living systems can prove to be carcinogenic. Therefore photocatalytic degradation of such toxic organic compounds in water, in the presence of semiconductor powders has received much attention over the last two decades. Nanocrystalline titanium dioxide, TiO2, is a well studied and commonly used material for photocatalytic applications. However, the control of particle size, monodispersity, large catalytic surface for sufficient adsorption of organic pollutants, recovery and recycle of TiO2 nanoparticles are challenging tasks. Hence in the present study, titania was introduced into the nanopores (2-10 nm size) of MCM-41 to produce stable nanoparticles of uniform size and shape. Further, in order to lengthen the life time of the excited electrons/holes during photoreaction, tungsten atoms were incorporated in to the MCM-41 silica matrix in addition to titania loading.

  19. Optimisation of synergistic biomass-degrading enzyme systems for efficient rice straw hydrolysis using an experimental mixture design.

    Science.gov (United States)

    Suwannarangsee, Surisa; Bunterngsook, Benjarat; Arnthong, Jantima; Paemanee, Atchara; Thamchaipenet, Arinthip; Eurwilaichitr, Lily; Laosiripojana, Navadol; Champreda, Verawat

    2012-09-01

    Synergistic enzyme system for the hydrolysis of alkali-pretreated rice straw was optimised based on the synergy of crude fungal enzyme extracts with a commercial cellulase (Celluclast™). Among 13 enzyme extracts, the enzyme preparation from Aspergillus aculeatus BCC 199 exhibited the highest level of synergy with Celluclast™. This synergy was based on the complementary cellulolytic and hemicellulolytic activities of the BCC 199 enzyme extract. A mixture design was used to optimise the ternary enzyme complex based on the synergistic enzyme mixture with Bacillus subtilis expansin. Using the full cubic model, the optimal formulation of the enzyme mixture was predicted to the percentage of Celluclast™: BCC 199: expansin=41.4:37.0:21.6, which produced 769 mg reducing sugar/g biomass using 2.82 FPU/g enzymes. This work demonstrated the use of a systematic approach for the design and optimisation of a synergistic enzyme mixture of fungal enzymes and expansin for lignocellulosic degradation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Convenient synthesis of peony-like FeWO4 with super adsorbent properties for efficient degradation of organic dye

    Science.gov (United States)

    Deng, Xixi; Xie, Guomeng; Liu, Xin; Wu, Yi; Qin, Lizhao; Li, Qing

    2017-07-01

    Uniform peony-like FeWO4 (average diameter 430 nm) was synthesized by using a convenient solvothermal route in the presence of ethylene glycol and β-cyclodextrin. Using some research techniques, it was verified that the product is phase-pure and well-crystalline peony-like FeWO4, which was made up of many small nanosheets with a thickness of about 10 nm. The specific surface area and the band gap energy of the peony-like FeWO4 were 67.836 m2 g-1 and 1.87 eV, respectively. The product showed an extremely fast adsorbent speed and an excellent adsorbtion capacity for organic dyes. In particular, for methylene blue (MB), the adsorption capacities of the peony-like FeWO4 reached as high as 69.4 mg g-1 in only 5 min. The pseudo-second-order model and Langmuir isotherm model showed good fit with the adsorption data. According to the Langmuir isotherm model, the maximum adsorption capacity was 79.18 mg g-1 for MB. In addition, in the presence of H2O2, the peony-like FeWO4 showed good catalytic performance such that 98% of MB was degraded in only 32 min.

  1. Bismuth oxyiodide incorporated reduced graphene oxide nanocomposite material as an efficient photocatalyst for visible light assisted degradation of organic pollutants

    Science.gov (United States)

    Vinoth, R.; Babu, S. Ganesh; Ramachandran, R.; Neppolian, B.

    2017-10-01

    Herein, Bismuth oxyiodide (BiOI) - reduced graphene oxide (rGO) photocatalysts were prepared via simple hydrothermal method. The BiOI-rGO photocatalyst exhibited high crystallinity with tetragonal phase of BiOI. In addition, the electronic interaction between rGO sheet and BiOI reduced the band-gap value from 1.86 eV of bare BiOI to 1.51 eV of BiOI-rGO (6 wt%) photocatalyst. More interestingly, the rGO showed a strong influence on tailoring the morphology of BiOI to different nanostructures with different rGO loading (wt%), which further reflected differences in the photocatalytic activity. A significant quenching in the photoluminescence intensity of rGO supported BiOI photocatalyst confirmed the effective suppression of electron-hole pair recombination. The optimized rGO (4 wt%) loaded BiOI photocatalyst significantly improved the photocatalytic activity (∼85%) towards the degradation of methyl orange (MO) dye compared to that of pristine BiOI (∼29%). Thus, around three folds enhancement in the photocatalytic activity of BiOI-rGO (4 wt%) catalyst was mainly attributed to ultrafast separation of electron-hole pairs and rapid transportation of carriers by rGO support. The superior photocatalytic activity demonstrated by this newly synthesized BiOI-rGO photocatalyst makes it's a potential candidate for environmental remediation process.

  2. Efficient photocatalytic degradation of organic pollutants by magnetically recoverable nitrogen-doped TiO2 nanocomposite photocatalysts under visible light irradiation.

    Science.gov (United States)

    Hamzezadeh-Nakhjavani, Sahar; Tavakoli, Omid; Akhlaghi, Seyed Parham; Salehi, Zeinab; Esmailnejad-Ahranjani, Parvaneh; Arpanaei, Ayyoob

    2015-12-01

    Preparation of novel nanocomposite particles (NCPs) with high visible-light-driven photocatalytic activity and possessing recovery potential after advanced oxidation process (AOP) is much desired. In this study, pure anatase phase titania (TiO2) nanoparticles (NPs) as well as three types of NCPs including nitrogen-doped titania (TiO2-N), titania-coated magnetic silica (Fe3O4 cluster@SiO2@TiO2 (FST)), and a novel magnetically recoverable TiO2 nanocomposite photocatalyst containing nitrogen element (Fe3O4 cluster@SiO2@TiO2-N (FST-N)) were successfully synthesized via a sol-gel process. The photocatalysts were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM) with an energy-dispersive X-ray (EDX) spectroscopy analysis, X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), and vibrating sample magnetometer (VSM). The photocatalytic activity of as-prepared samples was further investigated and compared with each other by degradation of phenol, as a model for the organic pollutants, in deionized (DI) water under visible light irradiation. The TiO2-N (55 ± 1.5%) and FST-N (46 ± 1.5%) samples exhibited efficient photocatalytic activity in terms of phenol degradation under visible light irradiation, while undoped samples were almost inactive under same operating conditions. Moreover, the effects of key operational parameters, the optimum sample calcination temperature, and reusability of FST-N NCPs were evaluated. Under optimum conditions (calcination temperature of 400 °C and near-neutral reaction medium), the obtained results revealed efficient degradation of phenol for FST-N NCPs under visible light irradiation (46 ± 1.5%), high yield magnetic separation and efficient reusability of FST-N NCPs (88.88% of its initial value) over 10 times reuse.

  3. Efficient methanogenic degradation of alcohol ethoxylates and microbial community acclimation in treatment of municipal wastewater using a submerged anaerobic membrane bioreactor.

    Science.gov (United States)

    Nie, Yulun; Niu, Qigui; Kato, Hiroyuki; Sugo, Toshiki; Tian, Xike; Li, Yu-You

    2017-02-01

    The effect of alcohol ethoxylates on the treatment of municipal wastewater by a submerged anaerobic membrane bioreactor was investigated by a 400days operation including the treatment efficiency, methanogenic activity of sludge and microbial community structure. The results indicated that alcohol ethoxylates (5.0-200mg/L) was efficiently degraded and converted into methane due to the similar COD removal 95.5-98.8% and rising biogas production rate (2.30-4.25L/d) compared with control (96.8% and 2.55L/d). The microbes in sludge could copy with the presence of alcohol ethoxylates in wastewater by releasing more SMP and EPS, which caused a higher membrane fouling rate. Moreover, via long term acclimation, the specific methanogenic activity of sludge was greatly enhanced due to the changes of microbial community structure. Hence, the sludge self-acclimation to alcohol ethoxylates was responsible to the efficient methane recovery in treatment of municipal wastewater. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Ultrasonic-assisted one-pot preparation of ZnO/Ag3VO4 nanocomposites for efficiently degradation of organic pollutants under visible-light irradiation

    Science.gov (United States)

    Kiantazh, Fariba; Habibi-Yangjeh, Aziz

    2015-11-01

    We report a facile ultrasonic-assisted one-pot method for preparation of ZnO/Ag3VO4 nanocomposites with different mole fractions of silver vanadate. The preparation method has considerable merits such as short preparation time, large-scale, and one-pot strategy. The resultant samples were fairly characterized by means of XRD, EDX, SEM, TEM, UV-vis DRS, FT-IR, and PL techniques. Visible-light activity of the resultant samples was investigated by degradation of rhodamine B (RhB), methylene blue (MB), and methyl orange (MO). Among the prepared nanocomposites, the ZnO/Ag3VO4 nanocomposite with 0.073 mole fraction of Ag3VO4 exhibited the best activity and excessive amount of Ag3VO4 resulted in decrease of the activity. Photocatalytic activity of this nanocomposite under visible-light irradiation is about 21, 56, and 2.8-fold higher than that of the ZnO sample in degradation of RhB, MB, and MO, respectively. The highly enhanced activity of the nanocomposite was attributed to greater generation of electron-hole pairs, due to photosensitizing role of Ag3VO4 under visible-light irradiation, and efficiently separation of the photogenerated electron-hole pairs, due to formation of n-n heterojunction between the counterparts. Furthermore, it was revealed that the photocatalytic activity largely depends on ultrasonic irradiation time, calcination temperature, and scavengers of the reactive species.

  5. A highly efficient immobilized ZnO/Zn photoanode for degradation of azo dye Reactive Green 19 in a photocatalytic fuel cell.

    Science.gov (United States)

    Lee, Sin-Li; Ho, Li-Ngee; Ong, Soon-An; Wong, Yee-Shian; Voon, Chun-Hong; Khalik, Wan Fadhilah; Yusoff, Nik Athirah; Nordin, Noradiba

    2017-01-01

    Photocatalytic fuel cell (PFC) is a potential wastewater treatment technology that can generate electricity from the conversion of chemical energy of organic pollutants. An immobilized ZnO/Zn fabricated by sonication and heat attachment method was applied as the photoanode and Pt/C plate was used as the cathode of the PFC in this study. Factors that affect the decolorization efficiency and electricity generation of the PFC such as different initial dye concentrations and pH were investigated. Results revealed that the degradation of Reactive Green 19 (RG19) was enhanced in a closed circuit PFC compared with that of a opened circuit PFC. Almost 100% decolorization could be achieved in 8 h when 250 mL of 30 mg L-1 of RG19 was treated in a PFC without any supporting electrolyte. The highest short circuit current of 0.0427 mA cm-2 and maximum power density of 0.0102 mW cm-2 was obtained by PFC using 30 mg L-1 of RG19. The correlation between dye degradation, conductivity and voltage output were also investigated and discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Self-assembly of ultrathin Cu2MoS4 nanobelts for highly efficient visible light-driven degradation of methyl orange.

    Science.gov (United States)

    Zhang, Ke; Chen, Wenxing; Lin, Yunxiang; Chen, Haiping; Haleem, Yasir A; Wu, Chuanqiang; Ye, Fei; Wang, Tianxing; Song, Li

    2015-11-21

    We demonstrate ultrathin self-assembled Cu2MoS4 nanobelts synthesized by using Cu2O as the starting sacrificial template via a hydrothermal method. The nanobelts exhibit strong light absorption over a broad wavelength spectrum, suggesting their potential application as photocatalysts. The photocatalytic activity of nanobelts is evaluated by the degradation of Methyl Orange (MO) dye under visible light irradiation. Notably, the nanobelts can completely degrade 100 mL of 15 mg mL(-1) MO in 20 minutes with excellent recycling and structural stability, suggesting their excellent photocatalytic performance. In comparison with a sheet-like sample, the high efficiency of the self-assembled Cu2MoS4 nanobelts is attributed to a high surface area and a unique band gap, agreeing with the nitrogen adsorption analysis and photoluminescence spectra. This study offers a self-assembled synthetic route to create new multifunctional nanoarchitectures composed of atomic layers, and thus may open a window for greatly extending potential applications in water pollution treatment, photocatalytic water-splitting, solar cells and other related fields.

  7. Effect of the calcination temperature on the photocatalytic efficiency of acidic sol-gel synthesized TiO2nanoparticles in the degradation of alprazolam.

    Science.gov (United States)

    Romeiro, Andreia; Freitas, Diana; Emília Azenha, M; Canle, Moisés; Burrows, Hugh D

    2017-06-14

    We report a comparative study on the photodegradation of the widely used benzodiazepine psychoactive drug alprazolam (8-chloro-1-methyl-6-phenyl-4H-[1,2,4]triazolo[4,3-a][1,4]benzodiazepine, ALP) using direct photolysis, and titanium dioxide photocatalyzed reaction. Titanium dioxide photocatalysts were prepared as nanoparticles by acidic sol-gel methods, calcined at two different temperatures, and their behavior compared with P25 (Degussa type) TiO 2 . Efficient photodegradation was observed in the photocatalytic process, with over 90% degradation after 90 minutes under optimized conditions. Triazolaminoquinoline, 5-chloro-(5-methyl-4H-1,2,4-triazol-4-yl)benzophenone, triazolbenzophenone, and α-hydroxyalprazolam were identified as the degradation products by fluorescence spectroscopy and HPLC-MS. A comparison with the literature suggests that 8H-alprazolam may also be formed. Good mineralization was observed with TiO 2 photocatalysts. ALP photodegradation with TiO 2 follows pseudo-first order kinetics, with rates depending on the photocatalyst used. The effects of the quantity of the photocatalyst and concentration of alprazolam were studied.

  8. Coupling of Nanocrystalline Anatase TiO2 to Porous Nanosized LaFeO3 for Efficient Visible-Light Photocatalytic Degradation of Pollutants

    Science.gov (United States)

    Humayun, Muhammad; Li, Zhijun; Sun, Liqun; Zhang, Xuliang; Raziq, Fazal; Zada, Amir; Qu, Yang; Jing, Liqiang

    2016-01-01

    In this work we have successfully fabricated nanocrystalline anatase TiO2/perovskite-type porous nanosized LaFeO3 (T/P-LFO) nanocomposites using a simple wet chemical method. It is clearly demonstrated by means of atmosphere-controlled steady-state surface photovoltage spectroscopy (SPS) responses, photoluminescence spectra, and fluorescence spectra related to the formed OH− radical amount that the photogenerated charge carriers in the resultant T/P-LFO nanocomposites with a proper mole ratio percentage of TiO2 display much higher separation in comparison to the P-LFO alone. This is highly responsible for the improved visible-light activities of T/P-LFO nanocomposites for photocatalytic degradation of gas-phase acetaldehyde and liquid-phase phenol. This work will provide a feasible route to synthesize visible-light responsive nano-photocatalysts for efficient solar energy utilization. PMID:28344279

  9. Coupling of Nanocrystalline Anatase TiO2 to Porous Nanosized LaFeO3 for Efficient Visible-Light Photocatalytic Degradation of Pollutants

    Directory of Open Access Journals (Sweden)

    Muhammad Humayun

    2016-01-01

    Full Text Available In this work we have successfully fabricated nanocrystalline anatase TiO2/perovskite-type porous nanosized LaFeO3 (T/P-LFO nanocomposites using a simple wet chemical method. It is clearly demonstrated by means of atmosphere-controlled steady-state surface photovoltage spectroscopy (SPS responses, photoluminescence spectra, and fluorescence spectra related to the formed OH− radical amount that the photogenerated charge carriers in the resultant T/P-LFO nanocomposites with a proper mole ratio percentage of TiO2 display much higher separation in comparison to the P-LFO alone. This is highly responsible for the improved visible-light activities of T/P-LFO nanocomposites for photocatalytic degradation of gas-phase acetaldehyde and liquid-phase phenol. This work will provide a feasible route to synthesize visible-light responsive nano-photocatalysts for efficient solar energy utilization.

  10. New Porphyrin/Fe-Loaded TiO2 Composites as Heterogeneous Photo-Fenton Catalysts for the Efficient Degradation of 4-Nitrophenol

    Directory of Open Access Journals (Sweden)

    Giuseppe Mele

    2013-01-01

    Full Text Available A new class of porphyrin(Pp/Fe co-loaded TiO2 composites opportunely prepared by impregnation of [5,10,15,20-tetra(4-tert-butylphenyl] porphyrin (H2Pp or Cu(II[5,10,15,20-tetra(4-tert-butylphenyl] porphyrin (CuPp onto Fe-loaded TiO2 particles showed high activities by carrying out the degradation of 4-nitrophenol (4-NP as probe reaction in aqueous suspension under heterogeneous photo-Fenton-like reactions by using UV-visible light. The combination of porphyrin-Fe-TiO2 in the presence of H2O2 showed to be more efficient than the simple bare TiO2 or Fe-TiO2.

  11. Hydrogenated TiO2 nanobelts as highly efficient photocatalytic organic dye degradation and hydrogen evolution photocatalyst.

    Science.gov (United States)

    Tian, Jian; Leng, Yanhua; Cui, Hongzhi; Liu, Hong

    2015-12-15

    TiO2 nanobelts have gained increasing interest because of its outstanding properties and promising applications in a wide range of fields. Here we report the facile synthesis of hydrogenated TiO2 (H-TiO2) nanobelts, which exhibit excellent UV and visible photocatalytic decomposing of methyl orange (MO) and water splitting for hydrogen production. The improved photocatalytic property can be attributed to the Ti(3+) ions and oxygen vacancies in TiO2 nanobelts created by hydrogenation. Ti(3+) ions and oxygen vacancies can enhance visible light absorption, promote charge carrier trapping, and hinder the photogenerated electron-hole recombination. This work offers a simple strategy for the fabrication of a wide solar spectrum of active photocatalysts, which possesses significant potential for more efficient photodegradation, photocatalytic water splitting, and enhanced solar cells using sunlight as light source. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Construction and Characterization of Vitreoscilla Hemoglobin (VHb) with Enhanced Peroxidase Activity for Efficient Degradation of Textile Dye.

    Science.gov (United States)

    Zhang, Zidong; Li, Wei; Li, Haichao; Zhang, Jing; Zhang, Yuebin; Cao, Yufeng; Ma, Jianzhang; Li, Zhengqiang

    2015-09-01

    Pollution resulting from the discharge of textile dyes into water systems has become a major global concern. Because peroxidases are known for their ability to decolorize and detoxify textile dyes, the peroxidase activity of Vitreoscilla hemoglobin (VHb) has recently been studied. It is found that VHb and variants of this enzyme show great promise for enzymatic decolorization of dyes and may play a role in achieving their successful removal from industrial wastewater. The level of VHb peroxidase activity correlates with two amino acid residues present within the conserved distal pocket, at positions 53 and 54. In this work, sitedirected mutagenesis of these residues was performed and resulted in improved VHb peroxidase activity. The double mutant, Q53H/P54C, shows the highest dye decolorization and removal efficiency, with 70% removal efficiency within 5 min. UV spectral studies of Q53H/P54C reveals a more compact structure and an altered porphyrin environment (λSoret = 413 nm) relative to that of wild-type VHb (λSoret = 406), and differential scanning calorimetry data indicate that the VHb variant protein structure is more stable. In addition, circular dichroism spectroscopic studies indicate that this variant's increased protein structural stability is due to an increase in helical structure, as deduced from the melting temperature, which is higher than 90°C. Therefore, the VHb variant Q53H/P54C shows promise as an excellent peroxidase, with excellent dye decolorization activity and a more stable structure than wild-type VHb under high-temperature conditions.

  13. Degradation of Congo red pollutants using microwave derived SrFe{sub 12}O{sub 19}: An efficient magnetic photocatalyst under visible light

    Energy Technology Data Exchange (ETDEWEB)

    Mohanta, O.; Singhbabu, Y.N. [CSIR-National Metallurgical Laboratory, Jamshedpur 831 007 (India); Giri, S.K. [Department of Chemistry, North Orissa University, Baripada 757 001 (India); Dadhich, D. [CSIR-National Metallurgical Laboratory, Jamshedpur 831 007 (India); Das, N.N. [Department of Chemistry, North Orissa University, Baripada 757 001 (India); Sahu, R.K., E-mail: rksahu@nmlindia.org [CSIR-National Metallurgical Laboratory, Jamshedpur 831 007 (India)

    2013-07-05

    Highlights: ► Microwave assisted synthesis of pure and Al substituted SrFe{sub 12}O{sub 19} nanoparticles. ► The magnetic photocatalyst efficiently degrades Congo red under visible/sun lights. ► Reduction of band gap to ∼1.5 eV is most contributing factor for the activity under visible/sun lights. ► Al doping prevents the electron–hole recombination of SrFe{sub 12}O{sub 19} to enhance the efficacy by 10%. ► Easy recovery of photocatalysts by low strength magnetic fields after the catalytic run for possible reuse. -- Abstract: The photocatalytic behavior of magnetic SrFe{sub 12}O{sub 19} and SrFe{sub 11.4}Al{sub 0.6}O{sub 19} under visible and sun lights was evaluated using Congo red (CR) as a model dye. Synthesis of pure and Al substituted SrFe{sub 12}O{sub 19} by microwave combustion method followed by calcination at 950 °C yielded single phase materials having particle sizes and surface areas in the ranges ∼120–180 nm and 3.5–5.5 m{sup 2}/g, respectively. The experimental band gaps (1.5–1.56 eV), derived from UV–Vis diffuse reflectance spectra, matched well with those calculated (1.86–1.91 eV) theoretically from electronic structure data using density functional theory. Both the samples efficiently degraded CR under visible/sun lights and the low band gap of the materials was mainly responsible for the activity. Slightly higher (∼10%) activity of SrFe{sub 11.4}Al{sub 0.6}O{sub 19} was primarily attributed to Al doping which prevented the electron–hole recombination. Reasonably high values of magnetization (∼52 emu/g at 300 K) was beneficial in separating the catalysts from the reaction cell at a low strength magnetic field after the reaction. These magnetic photocatalysts may be exploited further for the degradation of other dyes for their possible use in remediation of wastewater.

  14. Heterogeneous photocatalysis on construction materials: effect of catalyst properties on the efficiency for degrading NOx and self cleaning

    Directory of Open Access Journals (Sweden)

    Bengtsson, N.

    2014-05-01

    Full Text Available This paper analyzes the effect of some properties of different catalysts on the photocatalytic activity. The efficiency has been determined for two different processes: NOx abatement and self-cleaning for Rhodamine B and tobacco extract being, the TiO2 based photocatalyst, supported as coatings on white mortar. Eight different catalysts were tested, seven commercial ones and one home-made catalyst with improved visible light absorption properties. Additionally, some of them were submitted to exposition to water and/or calcinations to alter their physical properties. A kinetic approach was used to evaluate the photocatalytic activity, being the first reaction constant (for NO and just empirical constants (for self-cleaning the parameters used for the comparison of the different materials. As a result, the efficiency, even for ranking, is dependent on the type of contaminant used in the experiment. In general, NO oxidation and tobacco followed similar trends while no clear relations were found for Rhodamine B.En este trabajo se analiza el efecto de las propiedades de distintos catalizadores en la actividad fotocatalítica de degradación de NOx y autolimpieza, para Rodamina B y extracto de tabaco. Se han ensayado ocho fotocatalizadores, basados en TiO2 y soportados sobre mortero blanco; siete de ellos comerciales y uno sintetizado en el laboratorio con absorción mejorada en el visible. Adicionalmente, las propiedades físicas de algunos de ellos se alteraron mediante tratamientos con agua y/o por calcinación. La actividad fotocatalítica se ha evaluado mediante aproximación cinética, siendo la constante de reacción de primer orden (para NO y constantes empíricas de ajuste (para autolimpieza los parámetros de comparación entre materiales. Como resultado, la eficiencia depende del contaminante utilizado en el experimento de evaluación. En general, en este estudio, oxidación de NO y de extracto de tabaco presentan tendencias similares

  15. A single bivalent efficiently inhibits cyclin B1 degradation and polar body extrusion in mouse oocytes indicating robust SAC during female meiosis I.

    Directory of Open Access Journals (Sweden)

    Steffen Hoffmann

    Full Text Available The Spindle Assembly Checkpoint (SAC inhibits anaphase until microtubule-to-kinetochore attachments are formed, thus securing correct chromosome separation and preventing aneuploidy. Whereas in mitosis even a single unattached chromosome keeps the SAC active, the high incidence of aneuploidy related to maternal meiotic errors raises a concern about the lower efficiency of SAC in oocytes. Recently it was suggested that in mouse oocytes, contrary to somatic cells, not a single chromosome but a critical mass of chromosomes triggers efficient SAC pointing to the necessity of evaluating the robustness of SAC in oocytes. Two types of errors in chromosome segregation upon meiosis I related to SAC were envisaged: (1 SAC escape, when kinetochores emit SAC-activating signal unable to stop anaphase I; and (2 SAC deceive, when kinetochores do not emit the signal. Using micromanipulations and live imaging of the first polar body extrusion, as well as the dynamics of cyclin B1 degradation, here we show that in mouse oocytes a single bivalent keeps the SAC active. This is the first direct evaluation of SAC efficiency in mouse oocytes, which provides strong evidence that the robustness of SAC in mammalian oocytes is comparable to other cell types. Our data do not contradict the hypothesis of the critical mass of chromosomes necessary for SAC activation, but suggest that the same rule may govern SAC activity also in other cell types. We postulate that the innate susceptibility of oocytes to errors in chromosome segregation during the first meiotic division may not be caused by lower efficiency of SAC itself, but could be linked to high critical chromosome mass necessary to keep SAC active in oocyte of large size.

  16. Isolation and evaluation of native cellulose degrading microorganisms for efficient bioconversion of weed biomass and rice straw.

    Science.gov (United States)

    Mahanta, K; Jha, D K; Rajkhowa, D J; Kumar, Manoj

    2014-07-01

    Cellulose decomposing microorganisms (CDMs) are important for efficient bioconversion of plant biomasses. To this end, we isolated seven fungal isolates (Aspergillus wentii, Fusarium solani, Mucor sp., Penicillum sp., Trichoderma harzaianum, Trichoderma sp.1 and Trichoderma sp.2) and three bacterial isolates (bacterial isolate I, II and III) from partially decomposed farm yard manure, rice straw and vermicompost, and evaluated them for decomposition of rice straw (Oryza sativa), Ipomoea camea and Eichhornia crassipes biomass. CDMs inoculation, in general, reduced the composting period by 14-28 days in rice straw, 14-34 days in Eichhornia and 10-28 days in Ipomoea biomass over control. Of the 10 CDMs tested, Mucor sp. was found to be the most effective as Mucor-inoculated biomass required minimum time, i.e. 84, 68 and 80 days respectively for composting of rice straw, Eichhornia and Ipomoea biomass as against 112, 102 and 108 days required under their respective control. CDMs inoculation also narrowed down the C:N ratio of the composts which ranged from 19.1-22.7, 12.9-14.7 and 10.5-13.1 in rice straw, Eichhornia and Ipomoea biomass respectively as against 24.1, 17.1 and 16.2 in the corresponding control treatments. Aspergillus wentii, Fusarium solani, Mucor sp., and Penicillum sp. were found most effective (statistically at par) in reducing C:N ratio and causing maximum loss of carbon and dry matter in composted materials. These benefits of CDMs inoculation were also accompanied by significant increase in NPK contents in the composted materials.

  17. Micropollutant degradation, bacterial inactivation and regrowth risk in wastewater effluents: Influence of the secondary (pre)treatment on the efficiency of Advanced Oxidation Processes.

    Science.gov (United States)

    Giannakis, Stefanos; Voumard, Margaux; Grandjean, Dominique; Magnet, Anoys; De Alencastro, Luiz Felippe; Pulgarin, César

    2016-10-01

    In this work, disinfection by 5 Advanced Oxidation Processes was preceded by 3 different secondary treatment systems present in the wastewater treatment plant of Vidy, Lausanne (Switzerland). 5 AOPs after two biological treatment methods (conventional activated sludge and moving bed bioreactor) and a physiochemical process (coagulation-flocculation) were tested in laboratory scale. The dependence among AOPs efficiency and secondary (pre)treatment was estimated by following the bacterial concentration i) before secondary treatment, ii) after the different secondary treatment methods and iii) after the various AOPs. Disinfection and post-treatment bacterial regrowth were the evaluation indicators. The order of efficiency was Moving Bed Bioreactor > Activated Sludge > Coagulation-Flocculation > Primary Treatment. As far as the different AOPs are concerned, the disinfection kinetics were: UVC/H2O2 > UVC and solar photo-Fenton > Fenton or solar light. The contextualization and parallel study of microorganisms with the micropollutants of the effluents revealed that higher exposure times were necessary for complete degradation compared to microorganisms for the UV-based processes and inversed for the Fenton-related ones. Nevertheless, in the Fenton-related systems, the nominal 80% removal of micropollutants deriving from the Swiss legislation, often took place before the elimination of bacterial regrowth risk. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Efficient Degradation of Malathion in the Presence of Detergents Using an Engineered Organophosphorus Hydrolase Highly Expressed by Pichia pastoris without Methanol Induction.

    Science.gov (United States)

    Bai, Yun-Peng; Luo, Xiao-Jing; Zhao, Yu-Lian; Li, Chun-Xiu; Xu, Dian-Sheng; Xu, Jian-He

    2017-10-18

    The biodegradation of pesticides by organophosphorus hydrolases (OPHs) requires an efficient enzyme production technology in industry. Herein, a Pichia pastoris strain was constructed for the extracellular expression of PoOPHM9, an engineered malathion-degrading enzyme. After optimization, the maximum titer and yield of fermentation reached 50.8 kU/L and 4.1 gprotein/L after 3 days, with the highest space-time yield (STY) reported so far, 640 U L-1 h-1. PoOPHM9 displayed its high activity and stability in the presence of 0.1% (w/w) plant-derived detergent. Only 0.04 mg/mL enzyme could completely remove 0.15 mM malathion in aqueous solution within 20 min. Furthermore, 12 μmol malathion on apples and cucumbers surfaces was completely removed by 0.05 mg/mL PoOPHM9 in tap water after 35 min washing. The efficient production of the highly active PoOPHM9 has cleared a major barrier to biodegradation of pesticide residues in food industry.

  19. Novel Fe3O4@SiO2@Ag@Ni trepang-like nanocomposites: High-efficiency and magnetic recyclable catalysts for organic dye degradation

    Science.gov (United States)

    Li, Chao; Sun, Jun-Jie; Chen, Duo; Han, Guang-Bing; Yu, Shu-Yun; Kang, Shi-Shou; Mei, Liang-Mo

    2016-08-01

    A facile step-by-step approach is developed for synthesizing the high-efficiency and magnetic recyclable Fe3O4@SiO2@Ag@Ni trepang-like nanocomposites. This method involves coating Fe2O3 nanorods with a uniform silica layer, reduction in 10% H2/Ar atmosphere to transform the Fe2O3 into magnetic Fe3O4, and finally depositing Ag@Ni core-shell nanoparticles on the L-lysine modified surface of Fe3O4@SiO2 nanorods. The fabricated nanocomposites are further characterized by x-ray diffraction, transmission electron microscopy, scanning electron microscope, Fourier transform infrared spectroscopy, and inductively coupled plasma mass spectroscopy. The Fe3O4@SiO2@Ag@Ni trepang-like nanocomposites exhibit remarkably higher catalytic efficiency than monometallic Fe3O4@SiO2@Ag nanocomposites toward the degradation of Rhodamine B (RhB) at room temperature, and maintain superior catalytic activity even after six cycles. In addition, these samples could be easily separated from the catalytic system by an external magnet and reused, which shows great potential applications in treating waste water. Project supported by the National Basic Research Program of China (Grant No. 2015CB921502), the National Natural Science Foundation of China (Grant Nos. 11474184 and 11174183), the 111 Project (Grant No. B13029), and the Fundamental Research Funds of Shandong University, China.

  20. The feasibility of mobile computing for on-site inspection.

    Energy Technology Data Exchange (ETDEWEB)

    Horak, Karl Emanuel; DeLand, Sharon Marie; Blair, Dianna Sue

    2014-09-01

    With over 5 billion cellphones in a world of 7 billion inhabitants, mobile phones are the most quickly adopted consumer technology in the history of the world. Miniaturized, power-efficient sensors, especially video-capable cameras, are becoming extremely widespread, especially when one factors in wearable technology like Apples Pebble, GoPro video systems, Google Glass, and lifeloggers. Tablet computers are becoming more common, lighter weight, and power-efficient. In this report the authors explore recent developments in mobile computing and their potential application to on-site inspection for arms control verification and treaty compliance determination. We examine how such technology can effectively be applied to current and potential future inspection regimes. Use cases are given for both host-escort and inspection teams. The results of field trials and their implications for on-site inspections are discussed.

  1. On-Site Renewable Energy Generation

    Science.gov (United States)

    This guide describes a variety of approaches that local governments can use to advance climate and energy goals by meeting some or all of their electricity needs through on-site renewable energy generation.

  2. Combined thermotherapy and cryotherapy for efficient virus eradication: relation of virus distribution, subcellular changes, cell survival and viral RNA degradation in shoot tips.

    Science.gov (United States)

    Wang, Qiaochun; Cuellar, Wilmer J; Rajamäki, Minna-Liisa; Hirata, Yukimasa; Valkonen, Jari P T

    2008-03-01

    Accumulation of viruses in vegetatively propagated plants causes heavy yield losses. Therefore, supply of virus-free planting materials is pivotal to sustainable crop production. In previous studies, Raspberry bushy dwarf virus (RBDV) was difficult to eradicate from raspberry (Rubus idaeus) using the conventional means of meristem tip culture. As shown in the present study, it was probably because this pollen-transmitted virus efficiently invades leaf primordia and all meristematic tissues except the least differentiated cells of the apical dome. Subjecting plants to thermotherapy prior to meristem tip culture heavily reduced viral RNA2, RNA3 and the coat protein in the shoot tips, but no virus-free plants were obtained. Therefore, a novel method including thermotherapy followed by cryotherapy was developed for efficient virus eradication. Heat treatment caused subcellular alterations such as enlargement of vacuoles in the more developed, virus-infected cells, which were largely eliminated following subsequent cryotherapy. Using this protocol, 20-36% of the treated shoot tips survived, 30-40% regenerated and up to 35% of the regenerated plants were virus-free, as tested by ELISA and reverse transcription loop-mediated isothermal amplification. Novel cellular and molecular insights into RBDV-host interactions and the factors influencing virus eradication were obtained, including invasion of shoot tips and meristematic tissues by RBDV, enhanced viral RNA degradation and increased sensitivity to freezing caused by thermotherapy, and subcellular changes and subsequent death of cells caused by cryotherapy. This novel procedure should be helpful with many virus-host combinations in which virus eradication by conventional means has proven difficult.

  3. Temperature-dependent quantum efficiency degradation of K-Cs-Sb bialkali antimonide photocathodes grown by a triple-element codeposition method

    Science.gov (United States)

    Ding, Zihao; Karkare, Siddharth; Feng, Jun; Filippetto, Daniele; Johnson, Matthew; Virostek, Steve; Sannibale, Fernando; Nasiatka, James; Gaowei, Mengjia; Sinsheimer, John; Muller, Erik; Smedley, John; Padmore, Howard

    2017-11-01

    K-Cs-Sb bialkali antimonide photocathodes grown by a triple-element codeposition method have been found to have excellent quantum efficiency (QE) and outstanding near-atomic surface smoothness and have been employed in the VHF gun in the Advanced Photoinjector Experiment (APEX), however, their robustness in terms of their lifetime at elevated photocathode temperature has not yet been investigated. In this paper, the relationship between the lifetime of the K-Cs-Sb photocathode and the photocathode temperature has been investigated. The origin of the significant QE degradation at photocathode temperatures over 70 °C has been identified as the loss of cesium atoms from the K-Cs-Sb photocathode, based on the in situ x-ray analysis on the photocathode film during the decay process. The findings from this work will not only further the understanding of the behavior of K-Cs-Sb photocathodes at elevated temperature and help develop more temperature-robust cathodes, but also will become an important guide to the design and operation of the future high-field rf guns employing the use of such photocathodes.

  4. Study of the degradation of the external quantum efficiency of UV LEDs based on AlGaN/GaN heterostructures grown by chloride-hydride vapor-phase epitaxy

    Science.gov (United States)

    Shmidt, N. M.; Usikov, A. S.; Shabunina, E. I.; Chernyakov, A. E.; Sakharov, A. V.; Kurin, S. Yu.; Antipov, A. A.; Barash, I. S.; Roenkov, A. D.; Makarov, Yu. N.; Helava, H.

    2014-07-01

    Final stage of the degradation of the external quantum efficiency of AlGaN/GaN UV light-emitting diodes (LEDs), grown by chloride-hydride vapor-phase epitaxy, and high-power InGaN/GaN blue LEDs, produced by metal-organic vapor-phase epitaxy, has been comparatively studied. It is shown that one of these processes leading to a decrease in the quantum efficiency for both types of LEDs is the local defect formation involving the Gold-Weisberg mechanism in a system of extended defects. To prolong the service life of AlGaN/GaN UV LEDs to more than 2000 h, it is necessary to improve the nanostructural arrangement of the material of light-emitting structures and determine the contribution from the AlGaN composition disorder to the degradation of the external quantum efficiency.

  5. Efficiency of high molecular weight backbone degradable HPMA copolymer-prostaglandin E1 conjugate in promotion of bone formation in ovariectomized rats.

    Science.gov (United States)

    Pan, Huaizhong; Sima, Monika; Miller, Scott C; Kopečková, Pavla; Yang, Jiyuan; Kopeček, Jindřich

    2013-09-01

    Multiblock, high molecular weight, linear, backbone degradable HPMA copolymer-prostaglandin E1 (PGE1) conjugate has been synthesized by RAFT polymerization mediated by a new bifunctional chain transfer agent (CTA), which contains an enzymatically degradable oligopeptide sequence flanked by two dithiobenzoate groups, followed by postpolymerization aminolysis and thiol-ene chain extension. The multiblock conjugate contains Asp8 as the bone targeting moiety and enzymatically degradable bonds in the polymer backbone; in vivo degradation produces cleavage products that are below the renal threshold. Using an ovariectomized (OVX) rat model, the accumulation in bone and efficacy to promote bone formation was evaluated; low molecular weight conjugates served as control. The results indicated a higher accumulation in bone, greater enhancement of bone density, and higher plasma osteocalcin levels for the backbone degradable conjugate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Efficiency of High Molecular Weight Backbone Degradable HPMA Copolymer – Prostaglandin E1 Conjugate in Promotion of Bone Formation in Ovariectomized Rats

    Science.gov (United States)

    Pan, Huaizhong; Sima, Monika; Miller, Scott C.; Kopečková, Pavla; Yang, Jiyuan; Kopeček, Jindřich

    2013-01-01

    Multiblock, high molecular weight, linear, backbone degradable HPMA copolymer-prostaglandin E1 (PGE1) conjugate has been synthesized by RAFT polymerization mediated by a new bifunctional chain transfer agent (CTA), which contains an enzymatically degradable oligopeptide sequence flanked by two dithiobenzoate groups, followed by post-polymerization aminolysis and thiol-ene chain extension. The multiblock conjugate contains Asp8 as the bone-targeting moiety and enzymatically degradable bonds in the polymer backbone; in vivo degradation produces cleavage products that are below the renal threshold. Using an ovariectomized (OVX) rat model, the accumulation in bone and efficacy to promote bone formation was evaluated; low molecular weight conjugates served as control. The results indicated a higher accumulation in bone, greater enhancement of bone density, and higher plasma osteocalcin levels for the backbone degradable conjugate. PMID:23731780

  7. Efficient solar light-driven degradation of Congo red with novel Cu-loaded Fe3O4@TiO2 nanoparticles.

    Science.gov (United States)

    Arora, Priya; Fermah, Alisha; Rajput, Jaspreet Kaur; Singh, Harminder; Badhan, Jigyasa

    2017-08-01

    In this work, Cu-loaded Fe3O4@TiO2 core shell nanoparticles were prepared in a single pot by coating of TiO2 on Fe3O4 nanoparticles followed by Cu loading. X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), thermogravimetric analysis (TGA), Brunauer-Emmett- Teller (BET), vibrating sample magnetometry (VSM), X-ray photoelectron spectroscopy (XPS), and valence band X-ray photoelectron spectroscopy (VB XPS) techniques were used for characterization of as prepared nanoparticles. Synergism between copper and titania was evaluated by studying the solar light-driven photodegradation of Congo red dye solution in the presence of Fe3O4@TiO2 nanoparticles on one side and Cu-loaded Fe3O4@TiO2 nanoparticles on the other side. The latter performed better than the former catalyst, indicating the enhanced activity of copper-loaded catalyst. Further photodegradation was studied by three means, i.e., under ultraviolet (UV), refluxing, and solar radiations. Cu-loaded Fe3O4@TiO2 enhanced the degradation efficiency of Congo red dye. Thus, Cu act possibly by reducing the band gap of TiO2 and widening the optical response of semiconductor, as a result of which solar light could be used to carry out photocatalysis. Graphical abstract Photodegradation of congo red over Cu-loaded Fe3O4@TiO2 nanoparticles.

  8. Lowering rumen-degradable protein maintained energy-corrected milk yield and improved nitrogen-use efficiency in multiparous lactating dairy cows exposed to heat stress.

    Science.gov (United States)

    Kaufman, J D; Kassube, K R; Ríus, A G

    2017-10-01

    The objective of this study was to examine the effect of reducing rumen-degradable protein (RDP) and rumen-undegradable protein (RUP) proportions on feed intake, milk production, and N-use efficiency in primiparous and multiparous cows exposed to warm climates. Eighteen primiparous and 30 multiparous mid-lactation Holstein cows were used in a completely randomized design with a 2 × 2 factorial arrangement of treatments. Cows were randomly assigned to 1 of 4 dietary treatments formulated to contain 2 proportions of RDP (10 and 8%) and 2 proportions RUP (8 and 6%) of dry matter (DM) indicated as follows: (1) 10% RDP, 8% RUP; (2) 8% RDP, 8% RUP; (3) 10% RDP, 6% RUP; and (4) 8% RDP, 6% RUP. Protein sources were manipulated to obtain desired RDP and RUP proportions. Diets were isoenergetic and contained 50% forage and 50% concentrate (DM basis). Cows were individually fed the 10% RDP, 8% RUP diet 3 wk before treatment allocation. Cows were exposed to the prevailing Tennessee July and August temperature and humidity in a freestall barn with no supplemental cooling. Main effects and their interaction were tested using the Mixed procedure of SAS (least squares means ± standard error of the mean; SAS Institute Inc., Cary, NC). Observed values of nutrient intake and milk production were used to obtain NRC (2001) model predictions. Cows showed signs of heat stress throughout the study. Reducing from 10 to 8% RDP decreased dry matter intake (DMI; 0.9 kg/d) at 8% RUP, but increased DMI (2.6 kg/d) at 6% RUP in primiparous cows. Reducing from 10 to 8% RDP decreased milk yield (10%) at 8% RUP, but increased yield (14%) at 6% RUP. Treatments did not affect yield of energy-corrected milk. For multiparous cows, treatments did not affect DMI. Reducing from 10 to 8% RDP decreased yield of energy-corrected milk (3.4%) at 8% RUP, but increased yield (8.8%) at 6% RUP. Reducing from 10 to 8% RDP and 8 to 6% RUP both increased N-use efficiency for primiparous and multiparous cows. The NRC

  9. Polyethylene imine-grafted ACF@BiOI{sub 0.5}Cl{sub 0.5} as a recyclable photocatalyst for high-efficient dye removal by adsorption-combined degradation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hongyan [Collaborative Innovation Center of Suzhou Nano Science and Technology, College of Chemistry, Chemical Engineering and Materials Science, Suzhou University, Suzhou, Jiangsu 215123 (China); Li, Najun, E-mail: linajun@suda.edu.cn [Collaborative Innovation Center of Suzhou Nano Science and Technology, College of Chemistry, Chemical Engineering and Materials Science, Suzhou University, Suzhou, Jiangsu 215123 (China); State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Suzhou, Jiangsu 215123 (China); Chen, Dongyun; Xu, Qingfeng [Collaborative Innovation Center of Suzhou Nano Science and Technology, College of Chemistry, Chemical Engineering and Materials Science, Suzhou University, Suzhou, Jiangsu 215123 (China); State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Suzhou, Jiangsu 215123 (China); Lu, Jianmei, E-mail: lujm@suda.edu.cn [Collaborative Innovation Center of Suzhou Nano Science and Technology, College of Chemistry, Chemical Engineering and Materials Science, Suzhou University, Suzhou, Jiangsu 215123 (China); State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Suzhou, Jiangsu 215123 (China)

    2017-05-01

    Highlights: • A recyclable photocatalyst was facilely fabricated by immobilization and grafting. • Contribution from each component in the composite towards enhanced performance. • High removal efficiency was achieved under adsorption-combined degradation. • The composite photocatalyst can be easily separated from water for direct reuse. - Abstract: A recyclable photocatalyst with adsorption property was prepared for high-efficient complete removal of anionic dyes from water by synergetic adsorption and photocatalytic degradation. Firstly, binary bismuth oxyhalide composed as BiOI{sub 0.5}Cl{sub 0.5} was immobilized on activated carbon fibers (ACF) to get a recyclable photocatalyst (ACF@BiOI{sub 0.5}Cl{sub 0.5}) via one-step solvothermal method. Then it was modified with branched polyethylene imine (PEI) whose abundant amino groups can adsorb contaminants from water by electrostatic interaction. SEM images showed that the nanosheets-based flower-like photocatalytic microspheres uniformly distributed on the ACF surface after grafting of small amount of PEI. But from TGA results we can deduce that the percentage of PEI grafted onto ACF@BiOI{sub 0.5}Cl{sub 0.5} is about 18 wt%. During the synergistic process, the grafted PEI and immobilized BiOI{sub 0.5}Cl{sub 0.5} are worked as the adsorbent and the photocatalyst, respectively. In addition, ACF, as flexible, conductive and corrosion-resistant supports, are beneficial to the photocatalytic degradation process. So the obtained composite PEI-g-ACF@BiOI{sub 0.5}Cl{sub 0.5} has a high removal efficiency of contaminants under visible light irradiation with the synergistic effect of adsorption and photocatalytic degradation. And after facial separation without centrifuge, it can be reused without regeneration because of the real-time complete degradation of the adsorbed contaminants on the surface of the composite photocatalyst.

  10. A non-acid-assisted and non-hydroxyl-radical-related catalytic ozonation with ceria supported copper oxide in efficient oxalate degradation in water

    KAUST Repository

    Zhang, Tao

    2012-06-01

    Oxalate is usually used as a refractory model compound that cannot be effectively removed by ozone and hydroxyl radical oxidation in water. In this study, we found that ceria supported CuO significantly improved oxalate degradation in reaction with ozone. The optimum CuO loading amount was 12%. The molar ratio of oxalate removed/ozone consumption reached 0.84. The catalytic ozonation was most effective in a neutral pH range (6.7-7.9) and became ineffective when the water solution was acidic or alkaline. Moreover, bicarbonate, a ubiquitous hydroxyl radical scavenger in natural waters, significantly improved the catalytic degradation of oxalate. Therefore, the degradation relies on neither hydroxyl radical oxidation nor acid assistance, two pathways usually proposed for catalytic ozonation. These special characters of the catalyst make it suitable to be potentially used for practical degradation of refractory hydrophilic organic matter and compounds in water and wastewater. With in situ characterization, the new surface Cu(II) formed from ozone oxidation of the trace Cu(I) of the catalyst was found to be an active site in coordination with oxalate forming multi-dentate surface complex. It is proposed that the complex can be further oxidized by molecular ozone and then decomposes through intra-molecular electron transfer. The ceria support enhanced the activity of the surface Cu(I)/Cu(II) in this process. © 2012 Elsevier B.V.

  11. Magnetic recoverable MnFe₂O₄ and MnFe₂O₄-graphene hybrid as heterogeneous catalysts of peroxymonosulfate activation for efficient degradation of aqueous organic pollutants.

    Science.gov (United States)

    Yao, Yunjin; Cai, Yunmu; Lu, Fang; Wei, Fengyu; Wang, Xiaoyao; Wang, Shaobin

    2014-04-15

    Magnetic iron based materials are generally effective for many catalytic reactions and can be magnetically recovered after application, showing advantages than other metal oxides. In the present work, magnetic MnFe2O4 nanoparticle and MnFe2O4-reduced graphene oxide (rGO) hybrid were prepared and used as catalysts to activate peroxymonosulfate (PMS) to oxidatively degrade various organic pollutants in water. From a process of chemical deposition and reduction, MnFe2O4-rGO hybrids were produced with nanosized MnFe2O4 particles (ca. 13.2 nm). It was found that MnFe2O4 or MnFe2O4-rGO presented high activity in activating PMS to produce sulfate radicals for degradation of organic dyes (Methyl violet, Methyl orange, Methylene blue, Orange II and Rhodamine B) and could be separated with a magnet without any loss. The reaction kinetics, effect of different ion species CL(-),HCO3(-),CH3COO(-)and NO3(-) and Cl(-) strength, reaction temperature (25-65°C), catalytic stability, as well as degradation mechanism were comprehensively studied. The lower activation energy on MnFe2O4-rGO (25.7 kJ/mol) justify the higher chemical performance than that of MnFe2O4 (31.7 kJ/mol), suggesting that graphene plays a significant role in the enhanced degradation of dyes. More importantly, the as-prepared MnFe2O4 and MnFe2O4-rGO hybrid exhibited stable performance to remove the organic pollutants in wastewater with easy recycling and good stability by successive degradation experiments. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Efficient Photocatalytic Degradation of Norfloxacin in Aqueous Media by Hydrothermally Synthesized Immobilized TiO2/Ti Films with Exposed {001} Facets.

    Science.gov (United States)

    Sayed, Murtaza; Shah, Luqman Ali; Khan, Javed Ali; Shah, Noor S; Nisar, Jan; Khan, Hasan M; Zhang, Pengyi; Khan, Abdur Rahman

    2016-12-22

    In this study, a novel immobilized TiO2/Ti film with exposed {001} facets was prepared via a facile one-pot hydrothermal route for the degradation of norfloxacin from aqueous media. The effects of various hydrothermal conditions (i.e., solution pH, hydrothermal time (HT) and HF concentration) on the growth of {001} faceted TiO2/Ti film were investigated. The maximum photocatalytic performance of {001} faceted TiO2/Ti film was observed when prepared at pH 2.62, HT of 3 h and at HF concentration of 0.02 M. The as-prepared {001} faceted TiO2/Ti films were fully characterized by field-emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), high resolution transmission electron microscope (HR-TEM), and X-ray photoelectron spectroscopy (XPS). More importantly, the as-prepared {001} faceted TiO2/Ti film exhibited excellent photocatalytic performance toward degradation of norfloxacin in various water matrices (Milli-Q water, tap water, river water and synthetic wastewater). The individual influence of various anions (SO4(2-), HCO3(-), NO3(-), Cl(-)) and cations (K(+), Ca(2+), Mg(2+), Cu(2+), Na(+), Fe(3+)) usually present in the real water samples on the photocatalytic performance of as-prepared TiO2/Ti film with exposed {001} facet was investigated. The mechanistic studies revealed that (•)OH is mainly involved in the photocatalytic degradation of norfloxacin by {001} faceted TiO2/Ti film. In addition, norfloxacin degradation byproducts were investigated, on the basis of which degradation schemes were proposed.

  13. Bacterial Degradation of Pesticides

    DEFF Research Database (Denmark)

    Knudsen, Berith Elkær

    This PhD project was carried out as part of the Microbial Remediation of Contaminated Soil and Water Resources (MIRESOWA) project, funded by the Danish Council for Strategic Research (grant number 2104-08-0012). The environment is contaminated with various xenobiotic compounds e.g. pesticides....... Bioaugmentation i.e. addition of specific degrader organisms, has been suggested as an environmentally friendly and economically competitive strategy for cleaning polluted sites. Several organisms have been isolated, capable of degrading different compounds. However the capacity to degrade the desired compound...... is just one requirement for successful bioaugmentation. There are several challenges that need to be overcome in order for bioaugmentation to be sufficiently efficient. The purpose of this PhD project was to study the degradative abilities of different bacteria, and, in collaboration with a fellow Ph...

  14. On-site test for cannabinoids in oral fluid.

    Science.gov (United States)

    Desrosiers, Nathalie A; Lee, Dayong; Schwope, David M; Milman, Garry; Barnes, Allan J; Gorelick, David A; Huestis, Marilyn A

    2012-10-01

    Oral fluid (OF) testing offers noninvasive sample collection for on-site drug testing; however, to date, test performance for Δ(9)-tetrahydrocannabinol (THC) detection has had unacceptable diagnostic sensitivity. On-site tests must accurately identify cannabis exposure because this drug accounts for the highest prevalence in workplace drug testing and driving under the influence of drugs (DUID) programs. Ten cannabis smokers (9 males, 1 female) provided written informed consent to participate in this institutional review board-approved study and smoked 1 6.8%-THC cigarette ad libitum. OF was collected with the Draeger DrugTest(®) 5000 test cassette and Quantisal™ device 0.5 h before and up to 22 h after smoking. Test cassettes were analyzed within 15 min (n = 66), and Quantisal GC-MS THC results obtained within 24 h. Final THC detection times and test performances were assessed at different cannabinoid cutoffs. Diagnostic sensitivity, diagnostic specificity, and efficiency at DrugTest 5000's 5 μg/L screening cutoff and various THC confirmation cutoffs were 86.2-90.7, 75.0-77.8, and 84.8-87.9%, respectively. Last detection times were >22 h, longer than previously suggested. Confirmation of 11-nor-9-carboxy-THC, absent in THC smoke, minimized the potential for passive OF contamination and still provided 22-h windows of detection, appropriate for workplace drug testing, whereas confirmation of cannabidiol, and/or cannabinol yielded shorter 6-h windows of detection, appropriate for DUID OF testing. The DrugTest 5000 on-site device provided high diagnostic sensitivity for detection of cannabinoid exposure, and the selection of OF confirmation analytes and cutoffs provided appropriate windows of detection to meet the goals of different drug testing programs. © 2012 American Association for Clinical Chemistry

  15. Polyethylene imine-grafted ACF@BiOI0.5Cl0.5 as a recyclable photocatalyst for high-efficient dye removal by adsorption-combined degradation

    Science.gov (United States)

    Li, Hongyan; Li, Najun; Chen, Dongyun; Xu, Qingfeng; Lu, Jianmei

    2017-05-01

    A recyclable photocatalyst with adsorption property was prepared for high-efficient complete removal of anionic dyes from water by synergetic adsorption and photocatalytic degradation. Firstly, binary bismuth oxyhalide composed as BiOI0.5Cl0.5 was immobilized on activated carbon fibers (ACF) to get a recyclable photocatalyst (ACF@BiOI0.5Cl0.5) via one-step solvothermal method. Then it was modified with branched polyethylene imine (PEI) whose abundant amino groups can adsorb contaminants from water by electrostatic interaction. SEM images showed that the nanosheets-based flower-like photocatalytic microspheres uniformly distributed on the ACF surface after grafting of small amount of PEI. But from TGA results we can deduce that the percentage of PEI grafted onto ACF@BiOI0.5Cl0.5 is about 18 wt%. During the synergistic process, the grafted PEI and immobilized BiOI0.5Cl0.5 are worked as the adsorbent and the photocatalyst, respectively. In addition, ACF, as flexible, conductive and corrosion-resistant supports, are beneficial to the photocatalytic degradation process. So the obtained composite PEI-g-ACF@BiOI0.5Cl0.5 has a high removal efficiency of contaminants under visible light irradiation with the synergistic effect of adsorption and photocatalytic degradation. And after facial separation without centrifuge, it can be reused without regeneration because of the real-time complete degradation of the adsorbed contaminants on the surface of the composite photocatalyst.

  16. Rapid and efficient visible light photocatalytic dye degradation using AFe{sub 2}O{sub 4} (A = Ba, Ca and Sr) complex oxides

    Energy Technology Data Exchange (ETDEWEB)

    Vijayaraghavan, T. [PSG Institute of Advanced Studies, Coimbatore 641004 (India); Suriyaraj, S.P.; Selvakumar, R. [Nanobiotechnology Laboratory, PSG Institute of Advanced Studies, Coimbatore 641004 (India); Venkateswaran, R. [PSG Institute of Advanced Studies, Coimbatore 641004 (India); Ashok, Anuradha, E-mail: anu@psgias.ac.in [PSG Institute of Advanced Studies, Coimbatore 641004 (India)

    2016-08-15

    Highlights: • Alkaline earth ferrites AFe{sub 2}O{sub 4} (A = Ba, Ca and Sr) were synthesized by sol–gel method. • Visible light photocatalytic activity of these ferrites were studied using congo red dye degradation. • BaFe{sub 2}O{sub 4} exhibited the best photocatalytic activity under visible light (xenon lamp) irradiation; CaFe{sub 2}O{sub 4} was the best photocatalyst under natural sun light irradiation. - Abstract: Photocatalytic activity of spinel type complex oxides has been investigated in this study. Alkaline earth ferrites AFe{sub 2}O{sub 4} (A = Ba, Ca, Sr) were synthesized by sol–gel method. Structural characterizations reveal that the synthesized ferrites have orthorhombic crystal structures with different space groups and cell dimensions when they have different alkaline earth metals in their A site. All the synthesized ferrites exhibited their bandgap in the range 2.14–2.19 eV. Their photocatalytic activities were studied using congo red dye under sunlight and xenon lamp radiation. The substitution of Ba, Ca and Sr at A site of these ferrites had varying impact on dye degradation process. Under xenon lamp irradiation, BaFe{sub 2}O{sub 4} exhibited the highest percentage of dye degradation (92% after 75 min). However, CaFe{sub 2}O{sub 4} showed the fastest degradation of the dye (70% within 15 min). In the absence of irradiation, SrFe{sub 2}O{sub 4} showed the highest dye adsorption (44% after 75 min).

  17. Ternary ZnO/Ag3VO4/Fe3O4 nanocomposites: Novel magnetically separable photocatalyst for efficiently degradation of dye pollutants under visible-light irradiation

    Science.gov (United States)

    Shekofteh-Gohari, Maryam; Habibi-Yangjeh, Aziz

    2015-10-01

    In this work, we successfully prepared a series of novel magnetically separable ZnO/Ag3VO4/Fe3O4 nanocomposites by a facile refluxing method using Fe3O4, zinc nitrate, silver nitrate, ammonium metavanadate, and sodium hydroxide as starting materials without using any post preparation treatments. The microstructure, purity, morphology, spectroscopic, and magnetic properties of the prepared samples were studied using XRD, EDX, SEM, TEM, UV-vis DRS, FT-IR, PL, and VSM techniques. The ZnO/Ag3VO4/Fe3O4 nanocomposite with 8:1 weight ratio of ZnO/Ag3VO4 to Fe3O4 has the superior activity in degradation of rhodamine B under visible-light irradiation. Photocatalytic activity of this nanocomposite is about 11.5-fold higher than that of the ZnO/Fe3O4 nanocomposite. The results showed that the preparation time and calcination temperature significantly affect on the photocatalytic activity. The trapping experiments revealed that superoxide ions and holes have major influence on the degradation reaction. Furthermore, the enhanced activity of the nanocomposite for degradation of two more dye pollutants was confirmed. Finally, the nanocomposite was magnetically separated from the treated solution after four successive cycles.

  18. An Easy-Made, Economical and Efficient Carbon-Doped Amorphous TiO2 Photocatalyst Obtained by Microwave Assisted Synthesis for the Degradation of Rhodamine B

    Science.gov (United States)

    Luna-Flores, Adan; Morales-Sánchez, Marco Antonio; Agustín-Serrano, Ricardo

    2017-01-01

    The search for novel materials and the development of improved processes for water purification have attracted the interest of researchers worldwide and the use of titanium dioxide in photocatalytic processes for the degradation of organic pollutants contained in water has been one of the benchmarks. Compared to crystalline titanium dioxide (cTiO2), the amorphous material has the advantages of having a higher adsorption capacity and being easier to dope with metal and non-metal elements. In this work, we take advantage of these two features to improve its photocatalytic properties in the degradation of Rhodamine B. The structural characterization by XRD analysis gives evidence of its amorphous nature and the SEM micrographs portray the disc morphology of 300 nm in diameter with heterogeneous grain boundaries. The degradation of Rhodamine B tests with the amorphous TiO2 using visible light confirm its improved catalytic activity compared to that of a commercial product, Degussa P25, which is a well-known crystalline material. PMID:29261118

  19. Visible light-driven novel nanocomposite (BiVO4/CuCr2O4) for efficient degradation of organic dye.

    Science.gov (United States)

    Bajaj, Rohit; Sharma, Madhulika; Bahadur, D

    2013-05-21

    In the present study, BiVO4/CuCr2O4 nanocomposites synthesized via a chemical route are applied as a photocatalyst for the degradation of methylene blue (MB) dye. The photocatalytic activity results indicated a substantial degradation of MB dye by ~90% over the surface of nanocomposite catalyst under visible light illumination. The nanocomposite showed a photocatalytic activity for MB dye degradation which is three times higher compared to that of BiVO4. This has been attributed to photogenerated electron-hole pair charge separation. The prepared photocatalysts were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-Vis absorption and photoluminescence spectroscopy. Furthermore, an oxidizing reagent such as H2O2 was added to the photocatalytic system, which may act as an alternative electron scavenger and resulting in a notably enhanced rate of pollutant destruction. In addition, the effect of polyaniline has also been studied by synthesizing an organic/inorganic hybrid material (BiVO4/CuCr2O4/PANI). It has been observed that 95% photodegradation of organic dye takes place on the nanocomposite surface with visible light. A possible mechanism explaining the origin of enhanced performance of nanocomposite and nanohybrid is proposed.

  20. Development of efficiency improved polymer-modified TiO2 for the photocatalytic degradation of an organic dye from wastewater environment

    Science.gov (United States)

    Sangareswari, Murugan; Meenakshi Sundaram, Mariappan

    2017-07-01

    In this study, the photocatalytic activity of polypyrrole-TiO2 nanocomposite was studied experimentally for the degradation of methylene blue (MB) dye under simulating solar light irradiation. To improve the photocatalytic activity of TiO2 under sunlight irradiation, conducting polymers such as polypyrrole (PPy) and its derivatives are generally used as photosensitizers. The PPy-TiO2 nanocomposite was prepared by the chemical oxidative polymerization method. The prepared nanocomposite showed better photocatalytic activity than bare TiO2 under sunlight irradiation for the degradation of MB dye. The prepared nanocomposite was subjected to characterization techniques such as SEM-EDAX, FT-IR, UV-DRS, XRD, TGA and PL spectral analysis. Different influencing operating parameters like initial concentration of dye, irradiation time, pH and amount of PPy-TiO2 nanocomposite used have also been studied. The optical density of the dye degradation was measured by UV-Visible spectrophotometer. The repeatability of photocatalytic activity was also tested. A plausible mechanism was proposed and discussed on the basis of experimental results.

  1. An Easy-Made, Economical and Efficient Carbon-Doped Amorphous TiO2 Photocatalyst Obtained by Microwave Assisted Synthesis for the Degradation of Rhodamine B

    Directory of Open Access Journals (Sweden)

    Adan Luna-Flores

    2017-12-01

    Full Text Available The search for novel materials and the development of improved processes for water purification have attracted the interest of researchers worldwide and the use of titanium dioxide in photocatalytic processes for the degradation of organic pollutants contained in water has been one of the benchmarks. Compared to crystalline titanium dioxide (cTiO2, the amorphous material has the advantages of having a higher adsorption capacity and being easier to dope with metal and non-metal elements. In this work, we take advantage of these two features to improve its photocatalytic properties in the degradation of Rhodamine B. The structural characterization by XRD analysis gives evidence of its amorphous nature and the SEM micrographs portray the disc morphology of 300 nm in diameter with heterogeneous grain boundaries. The degradation of Rhodamine B tests with the amorphous TiO2 using visible light confirm its improved catalytic activity compared to that of a commercial product, Degussa P25, which is a well-known crystalline material.

  2. On site DNA barcoding by nanopore sequencing.

    Directory of Open Access Journals (Sweden)

    Michele Menegon

    Full Text Available Biodiversity research is becoming increasingly dependent on genomics, which allows the unprecedented digitization and understanding of the planet's biological heritage. The use of genetic markers i.e. DNA barcoding, has proved to be a powerful tool in species identification. However, full exploitation of this approach is hampered by the high sequencing costs and the absence of equipped facilities in biodiversity-rich countries. In the present work, we developed a portable sequencing laboratory based on the portable DNA sequencer from Oxford Nanopore Technologies, the MinION. Complementary laboratory equipment and reagents were selected to be used in remote and tough environmental conditions. The performance of the MinION sequencer and the portable laboratory was tested for DNA barcoding in a mimicking tropical environment, as well as in a remote rainforest of Tanzania lacking electricity. Despite the relatively high sequencing error-rate of the MinION, the development of a suitable pipeline for data analysis allowed the accurate identification of different species of vertebrates including amphibians, reptiles and mammals. In situ sequencing of a wild frog allowed us to rapidly identify the species captured, thus confirming that effective DNA barcoding in the field is possible. These results open new perspectives for real-time-on-site DNA sequencing thus potentially increasing opportunities for the understanding of biodiversity in areas lacking conventional laboratory facilities.

  3. Visible light-induced photocatalytic degradation of Reactive Blue-19 over highly efficient polyaniline-TiO2nanocomposite: a comparative study with solar and UV photocatalysis.

    Science.gov (United States)

    Kalikeri, Shankramma; Kamath, Nidhi; Gadgil, Dhanashri Jayant; Shetty Kodialbail, Vidya

    2018-02-01

    Polyaniline-TiO 2 (PANI-TiO 2 ) nanocomposite was prepared by in situ polymerisation method. X-ray diffractogram (XRD) showed the formation of PANI-TiO 2 nanocomposite with the average crystallite size of 46 nm containing anatase TiO 2 . The PANI-TiO 2 nanocomposite consisted of short-chained fibrous structure of PANI with spherical TiO 2 nanoparticles dispersed at the tips and edge of the fibres. The average hydrodynamic diameter of the nanocomposite was 99.5 nm. The band gap energy was 2.1 eV which showed its ability to absorb light in the visible range. The nanocomposite exhibited better visible light-mediated photocatalytic activity than TiO 2 (Degussa P25) in terms of degradation of Reactive Blue (RB-19) dye. The photocatalysis was favoured under initial acidic pH, and complete degradation of 50 mg/L dye could be achieved at optimum catalyst loading of 1 g/L. The kinetics of degradation followed the Langmuir-Hinshelhood model. PANI-TiO 2 nanocomposite showed almost similar photocatalytic activity under UV and visible light as well as in the solar light which comprises of radiation in both UV and visible light range. Chemical oxygen demand removal of 86% could also be achieved under visible light, confirming that simultaneous mineralization of the dye occurred during photocatalysis. PANI-TiO 2 nanocomposites are promising photocatalysts for the treatment of industrial wastewater containing RB-19 dye.

  4. On-Site or Off-Site Renewable Energy Supply Options?

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Heiselberg, Per; Jensen, Rasmus Lund

    2012-01-01

    five technologies, i.e., two on-site options: (1) photovoltaic, (2) micro combined heat and power, and three off-site options: (1) off-site windmill, (2) share of a windmill farm and (3) purchase of green energy from the 100% renewable utility grid. The results indicate that in case of the on......-site renewable supply options, the energy efficiency should be the first priority in order to design a cost-optimal Net ZEB. However, the results are opposite for the off-site renewable supply options, and thus it is more costeffective to invest in renewable energy technologies than in energy efficiency....

  5. Synthesis and Characterization of High Efficiency and Stable Spherical Ag3PO4 Visible Light Photocatalyst for the Degradation of Methylene Blue Solutions

    Directory of Open Access Journals (Sweden)

    Liqin Qin

    2015-01-01

    Full Text Available A facile method for the synthesis of Ag3PO4 visible light photocatalyst has been developed to improve the photocatalytic activity and stability. The as-prepared samples are investigated by X-ray powder diffraction, scanning electron microscopy, infrared spectroscopy, photoluminescence (PL spectroscopy, and UV-Vis diffuse reflectance spectroscopy techniques. The results reveal that the prepared Ag3PO4 has cube structure with a band gap of 2.26 eV. The as-prepared samples show higher photocatalytic activity for methylene blue (MB degradation than that of N-TiO2 under visible light irradiation.

  6. ``Gauging'' Non-on-site Symmetries and Symmetry Protected Topological Phases

    Science.gov (United States)

    Hsieh, Chang-Tse; Cho, Gil Young; Ryu, Shinsei

    2015-03-01

    We gauge non-on-site symmetries, such as parity symmetries, for a general (1+1)D conformal field theory (CFT) which is the boundary of (2+1)D symmetry protected topological (SPT) phases. This provides an efficient method to diagnose stability of SPT phases with the discrete non-on-site symmetries. To gauge the non-on- site symmetries, we are naturally led to consider field theories defined on a non-orientied manifold, such as Klein bottle. The partner states of the ``vortices'' (or twist operators) of the gauged non-on-site symmetries, the so-called crosscap states, provide information about the classification of the corresponding SPT phases. Our method also provide a way to gauging time-reversal symmetry, which is ``topologically'' related to parity symmetry by CPT theorem. NSF Grants DMR-1064319.

  7. Highly efficient solar-driven photocatalytic degradation on environmental pollutants over a novel C fibers@MoSe2 nanoplates core-shell composite.

    Science.gov (United States)

    Wang, Meng; Peng, Zhijian; Qian, Jingwen; Li, Hong; Zhao, Zengying; Fu, Xiuli

    2018-01-10

    As an important member of two-dimensional transition metal dichalcogenides, MoSe2 has a wide range of photoelectrochemical properties. However, MoSe2 alone can not directly be used as photocatalyst for its poor performance owing to the strong recombination of photogenerated electron-hole pairs. Here, we propose a novel C fibers@MoSe2 nanoplates core-shell composite, which was prepared by a facile, one-step thermal evaporation method. The composite has a remarkable feature of numerous MoSe2 thin nanoplates grown in-situ, densely and even vertically on the surface of the C fibers. Due to the effective separation of photogenerated electron-hole pairs promoted by the prompt transfer of photogenerated electrons through C fibers, compared with commercially available pure MoSe2 powder, such composite exhibits greatly improved solar-driven photocatalytic activity and high stability for the degradation of various organic/inorganic environmental pollutants including methylene blue, rhodamine B, p-chlorophenol and K2Cr2O7 aqueous solutions, showing the great potential for environmental remediation by degrading toxic industrial chemicals in waste water using sunlight. Moreover, this one-step thermal evaporation is an easy-handling, eco-friendly and low-cost synthesis method, which is suitable for large-scale production. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Photovoltaic Degradation Risk: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, D. C.; Kurtz, S. R.

    2012-04-01

    The ability to accurately predict power delivery over the course of time is of vital importance to the growth of the photovoltaic (PV) industry. Important cost drivers include the efficiency with which sunlight is converted into power, how this relationship changes over time, and the uncertainty in this prediction. An accurate quantification of power decline over time, also known as degradation rate, is essential to all stakeholders - utility companies, integrators, investors, and researchers alike. In this paper we use a statistical approach based on historical data to quantify degradation rates, discern trends and quantify risks related to measurement uncertainties, number of measurements and methodologies.

  9. Pd-catalytic in situ generation of H2O2 from H2 and O2 produced by water electrolysis for the efficient electro-fenton degradation of rhodamine B.

    Science.gov (United States)

    Yuan, Songhu; Fan, Ye; Zhang, Yucheng; Tong, Man; Liao, Peng

    2011-10-01

    A novel electro-Fenton process was developed for wastewater treatment using a modified divided electrolytic system in which H2O2 was generated in situ from electro-generated H2 and O2 in the presence of Pd/C catalyst. Appropriate pH conditions were obtained by the excessive H+ produced at the anode. The performance of the novel process was assessed by Rhodamine B (RhB) degradation in an aqueous solution. Experimental results showed that the accumulation of H2O2 occurred when the pH decreased and time elapsed. The maximum concentration of H2O2 reached 53.1 mg/L within 120 min at pH 2 and a current of 100 mA. Upon the formation of the Fenton reagent by the addition of Fe2+, RhB degraded completely within 30 min at pH 2 with a pseudo first order rate constant of 0.109 ± 0.009 min(-1). An insignificant decline in H2O2 generation and RhB degradation was found after six repetitions. RhB degradation was achieved by the chemisorption of H2O2 on the Pd/C surface, which subsequently decomposed into •OH upon catalysis by Pd0 and Fe2+. The catalytic decomposition of H2O2 to •OH by Fe2+ was more powerful than that by Pd0, which was responsible for the high efficiency of this novel electro-Fenton process.

  10. Size-Controlled TiO{sub 2} nanocrystals with exposed {001} and {101} facets strongly linking to graphene oxide via p-Phenylenediamine for efficient photocatalytic degradation of fulvic acids

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Wen-Yuan; Zhou, Qi [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Chen, Xing, E-mail: xingchen@iim.ac.cn [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Laboratory of Nanomaterials and Environmental Detection, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031 (China); Yang, Yong [State Key Laboratory of High Performance Ceramics and Superfine Microstructure,Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Zhang, Yong [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Huang, Xing-Jiu [Laboratory of Nanomaterials and Environmental Detection, Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031 (China); Wu, Yu-Cheng, E-mail: ycwu@hfut.edu.cn [School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009 (China); Anhui Key Laboratory of Advanced Functional Materials and Devices, Hefei 230009 (China)

    2016-08-15

    Highlights: • N-RGO/TiO{sub 2} nanocomposites were prepared via one-step hydrothermal method. • Facets of TiO{sub 2} nanocrystals were modulated with addition of HF. • Sizes of TiO{sub 2} nanocrystals were controlled by the contents of RGO-NH{sub 2.} • Obtained N-RGO/TiO{sub 2} nanocomposites exhibited excellent photocatalytic activity and stability. - Abstract: Photocatalytic degradation is one of the most promising methods for removal of fulvic acids (FA), which is a typical category of natural organic contamination in groundwater. In this paper, TiO{sub 2}/graphene nanocomposites (N-RGO/TiO{sub 2}) were prepared via simple chemical functionalization and one-step hydrothermal method for efficient photodegradation of FA under illumination of a xenon lamp as light source. Here, p-phenylenediamine was used as not only the linkage chemical agent between TiO{sub 2} nanocrystals and graphene, but also the nitrogen dopant for TiO{sub 2} nanocrystals and graphene. During the hydrothermal process, facets of TiO{sub 2} nanocrystals were modulated with addition of HF, and sizes of TiO{sub 2} nanocrystals were controlled by the contents of graphene oxide functionalized with p-phenylenediamine (RGO-NH{sub 2}). The obtained N-RGO/TiO{sub 2} nanocomposites exhibited a much higher photocatalytic activity and stability for degradation of methyl blue (MB) and FA compared with other TiO{sub 2} samples under xenon lamp irradiation. For the third cycle, the 10wt%N-RGO/TiO{sub 2} catalyst maintains high photoactivity (87%) for the degradation of FA, which is much better than the TiO{sub 2}-N/F (61%) in 3 h. This approach supplies a new strategy to design and synthesize metal oxide and graphene oxide nanocomposites with highly efficient photocatalytic performance.

  11. Efficient photocatalytic degradation of tetrabromodiphenyl ethers and simultaneous hydrogen production by TiO2-Cu2O composite films in N2 atmosphere: Influencing factors, kinetics and mechanism.

    Science.gov (United States)

    Hu, Zhe; Wang, Xi; Dong, Haitai; Li, Shangyi; Li, Xukai; Li, Laisheng

    2017-10-15

    TiO2-Cu2O photocatalyst composite film with a heterostructure was synthesized on a copper substrate for 2,2',4,4'-tetrabromodiphenyl ether (BDE47) reduction. First, Cu2O film was synthesized by the electrochemical deposition method, and then TiO2 was coated on the surface of the Cu2O film. The morphology, surface chemical composition and optical characteristics of TiO2-Cu2O film were characterized. The degradation efficiency of BDE47 and hydrogen production by TiO2-Cu2O films was higher than those by pure TiO2 or Cu2O films. The highest BDE47 degradation efficiency of 90% and hydrogen production of 12.7mmolLliq(-1) after 150min were achieved by 67%TiO2-Cu2O films. The influencing factors were investigated in terms of film component, solvent condition, and initial pH. A kinetics study demonstrated that BDE47 degradation followed a pseudo-first-order model. Photocatalytic apparent reaction rate constant of BDE47 by TiO2-Cu2O films was 0.0070min(-1), which was 3.3 times of that by directly photolysis process. During photocatalytic debrmination process, the photogenerated holes were reserved in the valance band of Cu2O to oxidize methanol. Meanwhile, the partial photogenerated electrons transferred to the conduction band of TiO2 and directly eliminated the ortho-Br of BDE47 and yielded BDE28 and BDE15. The other partial photogenerated electrons reduced protons (H(+)) to form atomic hydrogen (H°), which could substitute the para-Br of BDE47 and generated BDE17 and produce hydrogen. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Improved stability and enhanced efficiency to degrade chlorimuron-ethyl by the entrapment of esterase SulE in cross-linked poly (γ-glutamic acid)/gelatin hydrogel

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Liqiang [State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang (China); University of Chinese Academy of Sciences, Beijing (China); Li, Xinyu; Li, Xu; Su, Zhencheng; Zhang, Chenggang; Xu, MingKai [State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang (China); Zhang, Huiwen, E-mail: hwzhang@iae.ac.cn [State Key Laboratory of Forest and Soil Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang (China)

    2015-04-28

    Highlights: • Esterase SulE was entrapped in a three-dimensional network of CPE. • CPE-SulE obviously improved thermostability, pH stability and reusability. • CPE-SulE displayed obviously enhanced efficiency in degrading chlorimuron-ethyl. • The three-dimensional network and kinetic parameters of CPE-SulE were analysed. • CPE-SulE possesses the great potential to remediate chlorimuron-ethyl contaminated in situ. - Abstract: Free enzymes often undergo some problems such as easy deactivation, low stability, and less recycling in biodegradation processes, especially in soil condition. A novel esterase SulE, which is responsible for primary degradation of a wide range of sulfonylurea herbicides by methyl or ethyl ester de-esterification, was expressed by strain Hansschlegelia sp. CHL1 and entrapped for the first time in an environment-friendly, biocompatible and biodegradable cross-linked poly (γ-glutamic acid)/gelatin hydrogel (CPE). The activity and stability of CPE-SulE were compared with free SulE under varying pH and temperature condition by measuring chlorimuron-ethyl residue. Meanwhile, the three-dimensional network of CPE-SulE was verified by scanning electron microscopy (SEM). The results showed that CPE-SulE obviously improved thermostability, pH stability and reusability compared with free SulE. Furthermore, CPE-SulE enhanced degrading efficiency of chlorimuron-ethyl in both soil and water system, especially in acid environment. The characteristics of CPE-SulE suggested the great potential to remediate chlorimuron-ethyl contaminated soils in situ.

  13. CTAB-Assisted Hydrothermal Synthesis of Bi2Sn2O7 Photocatalyst and Its Highly Efficient Degradation of Organic Dye under Visible-Light Irradiation

    Directory of Open Access Journals (Sweden)

    Weicheng Xu

    2013-01-01

    Full Text Available Pyrochlore-type Bi2Sn2O7 (BSO nanoparticles have been prepared by a hydrothermal method assisted with a cationic surfactant cetyltrimethylammonium bromide (CTAB. These BSO products were characterized by powder X-ray diffraction (XRD, infrared spectroscopy (IR, scanning electron microscopy (SEM, transmission electron microscopy (TEM, Brunauer-Emmett-Teller (BET, and UV-visible diffuse reflectance spectroscopy (DRS. The results indicated that CTAB alters the surface parameters and the morphology and enhances the photoinduced charge separation rate of BSO. The photocatalytic degradation test using rhodamine B as a model pollutant showed that the photocatalytic activity of the BSO assisted with CTAB was two times that of the reference BSO. Close investigation revealed that the size, the band gap, the structure, and the existence of impurity level played an important role in the photocatalytic activities.

  14. Efficient degradation of tetrabromobisphenol A by heterostructured Ag/Bi5Nb3O15 material under the simulated sunlight irradiation.

    Science.gov (United States)

    Guo, Yingna; Chen, Ling; Ma, Fengyan; Zhang, Shengqu; Yang, Yuxin; Yuan, Xing; Guo, Yihang

    2011-05-15

    Heterostructured metallic silver-layered bismuth niobate two-component system (Ag/Bi(5)Nb(3)O(15)) was developed for the first time by a mild hydrothermal method combined with photodeposition. The Ag/Bi(5)Nb(3)O(15) exhibited single-crystalline orthorhombic structure with small particle size (50-200 nm) and octahedral as well as sheet-like shape; additionally, it possessed photoresponse in both UV and visible region. As a novel alternative photocatalysts to TiO(2), the photocatalytic activity of the Ag/Bi(5)Nb(3)O(15) was evaluated by the degradation of tetrabromobisphenol A, a member from the family of the brominated flame retardant, under solar simulating Xe lamp irradiation, and enhanced photocatalytic activity in compared to Bi(5)Nb(3)O(15) itself and Degussa P25 was obtained. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Growth study of hierarchical Ag3PO4/LaCO3OH heterostructures and their efficient photocatalytic activity for RhB degradation.

    Science.gov (United States)

    Deonikar, Virendrakumar G; Patil, Santosh S; Tamboli, Mohaseen S; Ambekar, Jalindar D; Kulkarni, Milind V; Panmand, Rajendra P; Umarji, Govind G; Shinde, Manish D; Rane, Sunit B; Munirathnam, Nagegownivari R; Patil, Deepak R; Kale, Bharat B

    2017-08-09

    We have demonstrated the synthesis of Ag 3 PO 4 /LaCO 3 OH (APO/LCO) heterostructured photocatalysts by an in situ wet chemical method. From pre-screening evaluations of photocatalysts with APO/(x wt% LCO) composites with mass ratios of x = 5, 10, 15, 20, 25 and 30 wt%, we found that the APO/LCO (20 wt%) exhibited a superior photocatalytic activity for organic pollutant remediation. Therefore, an optimised photocatalyst APO/LCO (20 wt%) is selected for the present study and we investigate the effect of a mixed solvent system (H 2 O:THF) on the morphology, which has a direct effect on the photocatalytic performance. Interestingly, a profound effect on the morphological features of APO/LCO20 heterostructures was observed with variation in the ratio of the solvent system. From the FESEM study it is observed that the LCO spherical nanoparticles are transformed into nanorods with the variation of THF into the solvent system. Moreover, these LCO nanorods make intimate contact with the APO microstructures which is helpful for the improvement of the photocatalytic activity. The photocatalytic activities of the APO/LCO composites with different solvent ratios were evaluated by the degradation of rhodamine B (RhB) under visible light irradiation. Excellent photocatalytic activity was observed for the APO/LCO-2 (H 2 O : THF = 60 : 40) sample. This might be due to uniform covering of the APO microstructures by fine LCO rod-like structures offering intimate contact between the APO and LCO and providing proper channels for the degradation reactions. Furthermore, with an increasing THF volume ratio in the reaction system there was an increase of the dimensions of the LCO rod-like structures and also a loose compactness of their uniform intimate contact between the APO/LCO heterostructures. All in all, the enhanced photocatalytic activity of the APO/LCO heterostructures is attributed to the collective co-catalytic effect of LCO, by providing accelerated charge separation

  16. One-Pot Route towards Active TiO2 Doped Hierarchically Porous Cellulose: Highly Efficient Photocatalysts for Methylene Blue Degradation

    Directory of Open Access Journals (Sweden)

    Xiaoxia Sun

    2017-03-01

    Full Text Available In this study, novel photocatalyst monolith materials were successfully fabricated by a non-solvent induced phase separation (NIPS technique. By adding a certain amount of ethyl acetate (as non-solvent into a cellulose/LiCl/N,N-dimethylacetamide (DMAc solution, and successively adding titanium dioxide (TiO2 nanoparticles (NPs, cellulose/TiO2 composite monoliths with hierarchically porous structures were easily formed. The obtained composite monoliths possessed mesopores, and two kinds of macropores. Scanning Electron Microscope (SEM, Energy Dispersive Spectroscopy (EDS, Fourier Transform Infrared Spectroscopy (FT-IR, X-ray Diffraction (XRD, Brunauer-Emmett-Teller (BET, and Ultraviolet-visible Spectroscopy (UV-Vis measurements were adopted to characterize the cellulose/TiO2 composite monolith. The cellulose/TiO2 composite monoliths showed high efficiency of photocatalytic activity in the decomposition of methylene blue dye, which was decomposed up to 99% within 60 min under UV light. Moreover, the composite monoliths could retain 90% of the photodegradation efficiency after 10 cycles. The novel NIPS technique has great potential for fabricating recyclable photocatalysts with highly efficiency.

  17. Dual-Mode Nanoporous Copper by Dealloying Al-Cu-Nacl Bulk Alloys and Its High Degradation Efficiency Toward Methyl Orange

    Science.gov (United States)

    Yu, Nana; Jiang, Lianyu; Hou, Hongyan; Chen, Xiutong; Li, Jie; Geng, Haoran; Zhao, Degang

    2017-03-01

    In this work, a facile synthesis route was applied to fabricate nanoporous copper (NPC). As-sintered AlCu bulk alloys with (or without) NaCl that were fabricated by powder metallurgy were taken as precursors during the preparation of NPC via chemical dealloying. The effects of NaCl in the alloys on precursors and products were investigated. Scanning electron microscope (SEM) examinations showed that the addition of NaCl is really beneficial to the formation of a dual-mode pore structure. The x-ray diffraction (XRD) revealed that the AlCu phase formed at the powder metallurgy stage could be completely corroded in HCl solution in the as-dealloyed products, whereas it remains unchanged in the NaOH condition. SEM images showed that NPC was characterized by a three-dimensional, bicontinuous, uniform, or dual-mode ligament-channel structure with nanoscale length. There were no obvious AlCu blocks or other bulks in the NPC sample fabricated from Al67Cu33 alloys with NaCl. In addition, it exhibited hierarchical structures with two distinctive pore sizes, which results in the best photocatalytic properties of NPC. Moreover, the photocatalytic properties of NPC for methyl orange (MO) degradation in water solution were evaluated, and it miraculously showed enhanced photocatalytic performance of exceeding 99% at even a brief time.

  18. Ascorbic acid induced atrazine degradation.

    Science.gov (United States)

    Hou, Xiaojing; Huang, Xiaopeng; Ai, Zhihui; Zhao, Jincai; Zhang, Lizhi

    2017-04-05

    In this study, we systematically investigated the degradation efficiency and the degradation mechanism of atrazine in the presence of ascorbic acid at different pH values. Although atrazine could be degraded by ascorbic acid in a wide pH range from 4 to 12, its degradation under either acidic (pH≤4) or alkaline (pH≥12) condition was more efficient than under neutral condition (pH=7). This pH dependent atrazine degradation was related to the reactive characteristic of atrazine and the reductive activity of ascorbic acid. The ascorbic acid induced atrazine degradation pathways at different pH were investigated by comparing the atrazine degradation intermediates with liquid chromatography-mass spectrometry, high performance liquid chromatography and ion chromatography. It was found that more products were detected in presence of ascorbic acid at alkaline condition. The appearance of chloride ions confirmed the dechlorination of atrazine by ascorbic acid in the absence of molecular oxygen, while its dechlorination efficiency reached highest at pH 12. These results can shed light on the application of AA for the organic pollutant remediation. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Synthesis of core-shell TiO2@g-C3N4 hollow microspheres for efficient photocatalytic degradation of rhodamine B under visible light

    Science.gov (United States)

    Ma, Lina; Wang, Guohong; Jiang, Chuanjia; Bao, Helin; Xu, Qingchuan

    2018-02-01

    Core-shell composites with titanium dioxide (TiO2) hollow microsphere as the core and graphitic carbon nitride (g-C3N4) as the shell were fabricated via a two-step self-assembly procedure with the assistance of ultrasonic dispersion. The as-prepared composite samples with different g-C3N4 contents (0-20%) were thoroughly characterized and the photocatalytic activity was evaluated by the photocatalytic degradation of Rhodamine B (RhB) in aqueous solution under visible light. A g-C3N4 layer of approximately 80 nm was successfully coated on the surface of TiO2 hollow microspheres with a diameter of 1-3 μm, forming a heterostructure with close interfacial contact. The TiO2@g-C3N4 composite exhibited significantly enhanced photocatalytic activity as compared with pure TiO2 hollow microspheres. At an optimum weight ratio of g-C3N4 to TiO2 (15 wt.%), the photocatalytic activity of the composite sample was almost 3 times higher than that of reference TiO2 hollow microspheres. Moreover, the results of recycling test indicated that the TiO2@g-C3N4 composite had excellent stability. A possible photocatalytic reaction mechanism of TiO2@g-C3N4 composite was proposed, in which superoxide radical anions played the major role in the oxidation of RhB, and the separation of photogenerated charge carriers across the heterostructure interface inhibited electron-hole recombination, thus enhancing the photocatalytic activity.

  20. Comparative assessment of the efficiency of Fe-doped TiO2 prepared by two doping methods and photocatalytic degradation of phenol in domestic water suspensions

    Directory of Open Access Journals (Sweden)

    Mst. Shamsun Nahar, Kiyoshi Hasegawa, Shigehiro Kagaya and Shigeyasu Kuroda

    2007-01-01

    Full Text Available Fe-doped TiO2 particles responding to visible light were synthesized by impregnation and calcination method using TiO2 particle and Ti element, respectively. The optical and the chemical properties were characterized by measuring the X-ray diffraction (XRD and UV–visible spectroscopy. The onset of absorption shifted to longer wavelengths on doping TiO2 by the calcination process, which showed a better response as compared to the impregnation method. The photocatalytic reactivity was evaluated by the degradation of phenol with impregnated Fe-doped (0.5% w/w in Fe and calcined Fe-doped (FexTi1−xO2, x=0.005 (Fe/Ti molar ratio TiO2 separately in distilled and tap water. The characterization results have confirmed the advanced possibility of correlation between photoactivity and the special property of sulfur-containing calcined Fe-doped TiO2. In case of the coagulation of the undoped A-I and the Fe-doped B-I, the photoactivity showed a decrease due to the presence of natural electrolytes and due to the high pH of tap water, whereas in the case of the coagulation of calcined Fe-doped TiO2 prepared from sulfides (FexTiS2, the photoactivity showed an increase. In this study, highest catalytic activity was found to be strongly dependent both on catalyst structure and on the type of water used.

  1. Microwave-assisted solvothermal synthesis of flower-like Ag/AgBr/BiOBr microspheres and their high efficient photocatalytic degradation for p-nitrophenol

    Energy Technology Data Exchange (ETDEWEB)

    Li, Tingting, E-mail: tingtingli1983@hotmail.com [Department of Chemistry and Chemical Engineering, Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Changsha 410082 (China); State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Department of Environment and Chemical Engineering, Key Laboratory of Jiangxi Province for Ecological Diagnosis, Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China); Luo, Shenglian, E-mail: sllou@hnu.edu.cn [Department of Chemistry and Chemical Engineering, Key Laboratory of Environmental Biology and Pollution Control, Hunan University, Changsha 410082 (China); State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Department of Environment and Chemical Engineering, Key Laboratory of Jiangxi Province for Ecological Diagnosis, Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China); Yang, Lixia [Department of Environment and Chemical Engineering, Key Laboratory of Jiangxi Province for Ecological Diagnosis, Remediation and Pollution Control, Nanchang Hangkong University, Nanchang 330063 (China)

    2013-10-15

    Flower-like Ag/AgBr/BiOBr microspheres were successfully fabricated by the approach of microwave-assisted solvothermal and in situ photo-assisted reduction. A reactive ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C{sub 16}mim]Br) was employed as Br source in the presence of surfactant polyvinylpyrrolidone (PVP). The photocatalytic activity of Ag/AgBr/BiOBr towards the decomposition of p-nitrophenol under visible light irradiation was evaluated. The results indicated that Ag/AgBr/BiOBr showed enhanced photocatalytic activity towards p-nitrophenol, comparing with P25, BiOBr and Ag/AgBr. More than 96% of p-nitrophenol was decomposed in 3.5 h under visible-light irradation. The excellent photocatalytic activity of flower-like Ag/AgBr/BiOBr microspheres can be attributed to the large specific surface area, strong visible-light absorption, suitable energy band structure and surface plasmon resonance effect of Ag nanoparticles. The possible photocatalytic mechanism was proposed based on the active species test and band gap structure analysis. - Graphical abstract: The photocatalytic reaction mechanisms of the as-prepared Ag/AgBr/BiOBr. Display Omitted - Highlights: • Successful synthesis of flower-like Ag/AgBr/BiOBr microspheres. • The Ag/AgBr/BiOBr showed much higher photocatalytic activity towards p-nitrophenol as compared to BiOBr and Ag/AgBr. • The reasons for the excellent photocatalytic activity are the large specific surface area, strong visible-light absorption and surface plasmon resonance effect of Ag nanoparticles. • The O{sub 2}·{sup −}, Br{sup 0} and photogenerated h{sup +} play key roles in the photocatalytic degradation process.

  2. Improved stability and enhanced efficiency to degrade chlorimuron-ethyl by the entrapment of esterase SulE in cross-linked poly (γ-glutamic acid)/gelatin hydrogel.

    Science.gov (United States)

    Yang, Liqiang; Li, Xinyu; Li, Xu; Su, Zhencheng; Zhang, Chenggang; Xu, MingKai; Zhang, Huiwen

    2015-04-28

    Free enzymes often undergo some problems such as easy deactivation, low stability, and less recycling in biodegradation processes, especially in soil condition. A novel esterase SulE, which is responsible for primary degradation of a wide range of sulfonylurea herbicides by methyl or ethyl ester de-esterification, was expressed by strain Hansschlegelia sp. CHL1 and entrapped for the first time in an environment-friendly, biocompatible and biodegradable cross-linked poly (γ-glutamic acid)/gelatin hydrogel (CPE). The activity and stability of CPE-SulE were compared with free SulE under varying pH and temperature condition by measuring chlorimuron-ethyl residue. Meanwhile, the three-dimensional network of CPE-SulE was verified by scanning electron microscopy (SEM). The results showed that CPE-SulE obviously improved thermostability, pH stability and reusability compared with free SulE. Furthermore, CPE-SulE enhanced degrading efficiency of chlorimuron-ethyl in both soil and water system, especially in acid environment. The characteristics of CPE-SulE suggested the great potential to remediate chlorimuron-ethyl contaminated soils in situ. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Utilizing metal tolerance potential of soil fungus for efficient synthesis of gold nanoparticles with superior catalytic activity for degradation of rhodamine B.

    Science.gov (United States)

    Bhargava, Arpit; Jain, Navin; Khan, Mohd Azeem; Pareek, Vikram; Dilip, R Venkataramana; Panwar, Jitendra

    2016-12-01

    In recent years, the surging demand of nanomaterials has boosted unprecedented expansion of research for the development of high yielding and sustainable synthesis methods which can deliver nanomaterials with desired characteristics. Unlike the well-established physico-chemical methods which have various limitations, biological methods inspired by mimicking natural biomineralization processes have great potential for nanoparticle synthesis. An eco-friendly and sustainable biological method that deliver particles with well-defined shape, size and compositions can be developed by selecting a proficient organism followed by fine tuning of various process parameter. The present study revealed high metal tolerance ability of a soil fungus Cladosporium oxysporum AJP03 and its potential for extracellular synthesis of gold nanoparticles. The morphology, composition and crystallinity of nanoparticles were confirmed using standard techniques. The synthesized particles were quasi-spherical in shape with fcc packing and an average particle size of 72.32 ± 21.80 nm. A series of experiments were conducted to study the effect of different process parameters on particle size and yield. Biomass: water ratio of 1:5 and 1 mM precursor salt concentration at physiological pH (7.0) favoured the synthesis of well-defined gold nanoparticles with maximum yield. The as-synthesized nanoparticles showed excellent catalytic efficiency towards sodium borohydride mediated reduction of rhodamine B (2.5 × 10(-5) M) within 7 min of reaction time under experimental conditions. Presence of proteins as capping material on the nanoparticle surface was found to be responsible for this remarkable catalytic efficiency. The present approach can be extrapolated to develop controlled and up-scalable process for mycosynthesis of nanoparticles for diverse applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Synthesis of surface molecular imprinted TiO{sub 2}/graphene photocatalyst and its highly efficient photocatalytic degradation of target pollutant under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Cui, E-mail: laicui@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, Hunan (China); Wang, Man-Man [College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, Hunan (China); Zeng, Guang-Ming, E-mail: zgming@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, Hunan (China); Liu, Yun-Guo; Huang, Dan-Lian; Zhang, Chen; Wang, Rong-Zhong; Xu, Piao; Cheng, Min; Huang, Chao; Wu, Hai-Peng; Qin, Lei [College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, Hunan (China)

    2016-12-30

    Highlights: • The surface molecular imprinting technique was successfully combined with photocatalyst. • Molecularly imprinted photocatalyst exhibits recognition ability to the target molecules. • MIP-TiO{sub 2}/GR shows higher adsorption capacity and selectivity than NIP-TiO{sub 2}/GR. • The photocatalytic activity of MIP-TiO{sub 2}/GR is enhanced for target molecules. - Abstract: The molecular imprinted TiO{sub 2}/graphene photocatalyst (MIP-TiO{sub 2}/GR) was successfully prepared with bisphenol A (BPA) as the template molecule (target pollutant) and o-phenylenediamine (OPDA) as functional monomers by the surface molecular imprinting method. The combination between BPA and OPDA led to the formation of the precursor, and the subsequent polymerization of OPDA initiated by ultraviolet radiation can ensure the realization of MIP-TiO{sub 2}/GR. The samples were characterized by SEM, EDS, XRD, BET, UV–vis DRS and Zeta potential. In addition, adsorption capacities, adsorption selectivity and visible light photocatalytic performances of MIP-TiO{sub 2}/GR and non-imprinted TiO{sub 2}/graphene (NIP-TiO{sub 2}/GR) were evaluated. Moreover, the effects of pH and initial BPA concentration on removal efficiency of BPA were also investigated. The results showed that MIP-TiO{sub 2}/GR exhibited better adsorption capacity and adsorption selectivity towards the template molecule compared to NIP-TiO{sub 2}/GR due to the imprinted cavities on the surface of MIP-TiO{sub 2}/GR. Moreover, the photocatalytic activity of MIP-TiO{sub 2}/GR toward the target molecules was stronger than that of NIP-TiO{sub 2}/GR as a result of large adsorption capacity to target molecules and narrow band gap energy on MIP-TiO{sub 2}/GR. Therefore, modifying the photocatalyst by the surface molecular imprinting is a promising method to improve the molecule recognition and photocatalytic efficiency of photocatalyst for target pollutant.

  5. Fuzzy logic controllers for electrotechnical devices - On-site tuning approach

    Science.gov (United States)

    Hissel, D.; Maussion, P.; Faucher, J.

    2001-12-01

    Fuzzy logic offers nowadays an interesting alternative to the designers of non linear control laws for electrical or electromechanical systems. However, due to the huge number of tuning parameters, this kind of control is only used in a few industrial applications. This paper proposes a new, very simple, on-site tuning strategy for a PID-like fuzzy logic controller. Thanks to the experimental designs methodology, we will propose sets of optimized pre-established settings for this kind of fuzzy controllers. The proposed parameters are only depending on one on-site open-loop identification test. In this way, this on-site tuning methodology has to be compared to the Ziegler-Nichols one's for conventional controllers. Experimental results (on a permanent magnets synchronous motor and on a DC/DC converter) will underline all the efficiency of this tuning methodology. Finally, the field of validity of the proposed pre-established settings will be given.

  6. Degradation of CIGS solar cells

    OpenAIRE

    Theelen, M.J.

    2015-01-01

    Large scale commercial introduction of CIGS photovoltaics (PV) requires modules with low costs, high efficiencies and long and predictable lifetimes. Unfortunately,knowledge about the lifetime of CIGS PV is limited, which is reflected in the results of field studies: degradation rates varying from 0% to about 4% per year have been observed. Since warrantees are given out that the modules will still yield 80% of their initial power after 20 years of field exposure, degradation rates are often ...

  7. NiWO4-ZnO-NRGO ternary nanocomposite as an efficient photocatalyst for degradation of methylene blue and reduction of 4-nitro phenol

    Science.gov (United States)

    Sadiq, M. Mohamed Jaffer; Shenoy, U. Sandhya; Bhat, D. Krishna

    2017-10-01

    A novel NiWO4-ZnO-NRGO ternary nanocomposite has been efficiently synthesized by decorating nitrogen doped reduced graphene oxide (NRGO) with zinc oxide and nickel tungstate nanoparticles via a facile microwave irradiation technique and its capability to catalyze photodegradation of methylene blue (MB) dye in aqueous solution and reduction of 4-nitro phenol (4-NP) to 4-amino phenol (4-AP) using sodium borohydride was explored. The as-synthesized nanocomposite was characterized by X-ray diffraction (XRD), Raman spectroscopy, Brunauer-Emmett-Teller (BET) analysis, energy dispersive X-ray (EDX) analysis, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectroscopy and diffuse reflectance spectroscopy (DRS) techniques. The photocatalytic activity of the as-synthesized nanocomposite estimated through the photodegradation of MB under visible light irradiation showed 9 times improvement over pure NiWO4. It also showed excellent catalytic activity in reduction of 4-NP to 4-AP. The material also showed excellent stability and reusability. The entire study revealed that the novel NiWO4-ZnO-NRGO ternary nanocomposite can act as a promising bifunctional photocatalyst for environmental remediation and industrial application.

  8. Cr/S/TiO2-LOADED HOLLOW GLASS MICROSPHERES AS AN EFFICIENT AND RECYCLABLE CATALYST FOR THE PHOTOCATALYTIC DEGRADATION OF INDIGO CARMINE UNDER VISIBLE LIGHT

    Directory of Open Access Journals (Sweden)

    Xiuli Zhang

    Full Text Available Chromium and sulfur co-doped nanometer TiO2 hollow glass microspheres (Cr/S/TiO2-HGM were synthesized by a sol-gel method. Characterization used X-ray diffraction (XRD, scanning electron microscopy (SEM, energy-dispersive X-ray spectroscopy (EDX, N2 adsorption-desorption (Brunauer-Emmett-Teller (BET measurements and UV-Vis diffuse reflectance spectroscopy. The photocatalytic activity was evaluated by photodegradation of indigo carmine in an aqueous solution under visible light irradiation. The results indicated that the Cr/S/TiO2 containing 0.60% (atomic ratio chromium and 1.2% (atomic ratio sulfur calcined at 500 ºC for 2 h had high catalytic efficiency under visible light irradiation. The floating Cr/S/TiO2-HGM catalyst had greater photocatalytic activity than Cr/S/TiO2 powder. Therefore, Cr/S/TiO2-HGM is a promising, high-performing, visible-light-driven, and more reusable photocatalyst.

  9. On-site energy consumption at softwood sawmills in Montana

    Science.gov (United States)

    Dan Loeffler; Nathaniel Anderson; Todd A. Morgan; Colin B. Sorenson

    2016-01-01

    Total on-site energy requirements for wood product manufacturing are generally not well understood or publicly available, particularly at subregional scales, such as the state level. This article uses a mail survey of softwood sawmills in Montana to develop a profile of all on-site energy consumption. Energy use is delineated by fuel type on a production basis...

  10. Characterization of a highly efficient antibiotic-degrading metallo-β-lactamase obtained from an uncultured member of a permafrost community.

    Science.gov (United States)

    Pedroso, Marcelo Monteiro; Selleck, Christopher; Enculescu, Charmaine; Harmer, Jeffrey R; Mitić, Nataša; Craig, Whitney R; Helweh, Waleed; Hugenholtz, Philip; Tyson, Gene W; Tierney, David L; Larrabee, James A; Schenk, Gerhard

    2017-08-16

    Antibiotic resistance is a major global health problem, one that threatens to derail the benefits garnered from arguably the greatest success of modern medicine, the discovery of antibiotics. Among the most potent agents contributing to antibiotic resistance are metallo-β-lactamases (MBLs). The discovery of MBL-like enzymes in microorganisms that are not in contact with the human population is of particular concern as these proteins already have the in-built capacity to inactivate antibiotics, even though they may not need MBL activity for their survival. Here, we demonstrate that a microbiome from a remote and frozen environment in Alaska harbours at least one highly efficient MBL, LRA-8. LRA-8 is homologous to the B3 subgroup of MBLs and has a substrate profile and catalytic properties similar to well-known members of this enzyme family, which are expressed by major human pathogens. LRA-8 is predominantly a penicillinase, but is also active towards carbapenems, but not cephalosporins. Spectroscopic studies indicate that LRA-8 has an active site structure similar to that of other MBLs (in particular B3 subgroup representative AIM-1), and a combination of steady-state and pre-steady-state kinetic data demonstrate that the enzyme is likely to employ a metal ion-bridging hydroxide to initiate catalysis. The rate-limiting step is the decay of a chromophoric, tetrahedral intermediate, as is observed in various other MBLs. Thus, studying the properties of such "pristine" MBL-like proteins may provide insight into the structural plasticity of this family of enzymes that may facilitate functional promiscuity, while important insight into the evolution of MBLs may also be gained.

  11. Using microorganisms to aid in hydrocarbon degradation

    Energy Technology Data Exchange (ETDEWEB)

    Black, W.; Zamora, J. (Middle Tennessee State Univ., Murfreesboro (United States))

    1993-04-01

    Aliphatic hydrocarbons are threatening the potable water supply and the aquatic ecosystem. Given the right microbial inhabitant(s), a large portion of these aliphatic hydrocarbons could be biodegraded before reaching the water supply. The authors' purpose is to isolate possible oil-degrading organisms. Soil samples were taken from hydrocarbon-laden soils at petroleum terminals, a petroleum refinery waste-treatment facility, a sewage-treatment plant grease collector, a site of previous bioremediation, and various other places. Some isolates known to be good degraders were obtained from culture collection services. These samples were plated on a 10w-30 multigrade motor oil solid medium to screen for aliphatic hydrocarbon degraders. The degrading organisms were isolated, identified, and tested (CO[sub 2] evolution, BOD, and COD) to determine the most efficient degrader(s). Thirty-seven organisms were tested, and the most efficient degraders were Serratia marcescens, Escherichia coli, and Enterobacter agglomerans.

  12. Highly Efficient visible-light-induced photoactivity of magnetically retrievable Fe3O4@SiO2@Bi2WO6@g-C3N4 hierarchical microspheres for the degradation of organic pollutant and production of hydrogen

    Science.gov (United States)

    Lu, Dingze; Wang, Hongmei; Shen, Qingqing; Kondamareddy, Kiran Kumar; Neena D

    2017-07-01

    The new multifunctional composite Fe3O4@SiO2@Bi2WO6@g-C3N4 (FSBG) hierarchical microspheres with Bi2WO6/g-C3N4 heterostructure as an outer shell and Fe3O4@SiO2 as a magnetic core have been synthesized and characterized for photocatalytic applications. An efficient and adoptable approach of synthesizing magnetic Bi2WO6/g-C3N4 hierarchical microspheres of grape-like morphology is realized. The as-synthesized structures exhibit highly efficient visible-light absorption and separation efficiency of photo-induced charge. The visible-light-induced photocatalytic activity of g-C3N4, Fe3O4@SiO2@Bi2WO6, and FSBG is evaluated by investigating the photodegradation of Rhodamine B (RhB) and hydrogen (H2) out of water. The comparative study reveals that the FSBG microspheres exhibit an optimum visible-light-induced photocatalytic activity in degrading Rhodamin B (RhB), which is 3.06 and 1.92 times to that of g-C3N4 and Fe3O4@SiO2@Bi2WO6 systems respectively and 3.89 and 2.31 times in the production of hydrogen (H2) out of water, respectively. The FSBG composite microspheres also exhibit good magnetic recoverability. An alternate mechanism for the enhanced visible-light photocatalytic activity is given in the present manuscript.

  13. 1000kW on-site PAFC power plant development and demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Satomi, Tomohide; Koike, Shunichi [Phosphoric Acid Fuel Cell Technology Research Association (PAFC-TRA), Osaka (Japan); Ishikawa, Ryou [New Energy and Industrial Technology Development Organization (NEDO), Tokyo (Japan)

    1996-12-31

    Phosphoric Acid Fuel Cell Technology Research Association (PAFC-TRA) and New Energy and Industrial Technology Development Organization (NEDO) have been conducting a joint project on development of a 5000kW urban energy center type PAFC power plant (pressurized) and a 1000kW on-site PAFC power plant (non-pressurized). The objective of the technical development of 1000kW on-site PAFC power plant is to realize a medium size power plant with an overall efficiency of over 70% and an electrical efficiency of over 36%, that could be installed in a large building as a cogeneration system. The components and system integration development work and the plant design were performed in 1991 and 1992. Manufacturing of the plant and installation at the test site were completed in 1994. PAC test was carried out in 1994, and generation test was started in January 1995. Demonstration test is scheduled for 1995 and 1996.

  14. Pre-Mix and on-site mixing of fumigants

    OpenAIRE

    Ryan, R F; Shore, W. P.

    2010-01-01

    Pre-Mix or On-Site mixing, a common practice with liquid insecticides, has benefits of increased synergy with fumigants. Both Pre-Mix and On-Site mixing have some issues with compatibility (e.g., active ingredient chemical stability; material compatibility; reaction with other ingredients). In addition to its fumigant properties, carbon dioxide (CO₂), has a synergistic effect on other fumigants and reduces flammability. The general consensus on the amount of CO₂ to improve efficacy is in the ...

  15. Chitin Degradation In Marine Bacteria

    DEFF Research Database (Denmark)

    Paulsen, Sara; Machado, Henrique; Gram, Lone

    2015-01-01

    Introduction: Chitin is the most abundant polymer in the marine environment and the second most abundant in nature. Chitin does not accumulate on the ocean floor, because of microbial breakdown. Chitin degrading bacteria could have potential in the utilization of chitin as a renewable carbon...... and nitrogen source in the fermentation industry.Methods: Here, whole genome sequenced marine bacteria were screened for chitin degradation using phenotypic and in silico analyses.Results: The in silico analyses revealed the presence of three to nine chitinases in each strain, however the number of chitinases...... chitin regulatory system.Conclusions: This study has provided insight into the ecology of chitin degradation in marine bacteria. It also served as a basis for choosing a more efficient chitin degrading production strain e.g. for the use of chitin waste for large-scale fermentations....

  16. Use of ozone in a pilot-scale plant for textile wastewater pre-treatment: physico-chemical efficiency, degradation by-products identification and environmental toxicity of treated wastewater.

    Science.gov (United States)

    Somensi, Cleder A; Simionatto, Edésio L; Bertoli, Sávio L; Wisniewski, Alberto; Radetski, Claudemir M

    2010-03-15

    In this study, ozonation of raw textile wastewater was conducted in a pilot-scale plant and the efficiency of this treatment was evaluated based on the parameters color removal and soluble organic matter measured as chemical oxygen demand (COD), at two pH values (9.1 and 3.0). Identification of intermediate and final degradation products of ozone pre-treatment, as well as the evaluation of the final ecotoxicity (Lumistox test) of pre-treated wastewater, was also carried out. After 4h of ozone treatment with wastewater recirculation (flow rate of 0.45 m(3)h(-1)) the average efficiencies for color removal were 67.5% (pH 9.1) and 40.6% (pH 3.0), while COD reduction was 25.5% (pH 9.1) and 18.7% (pH 3.0) for an ozone production capacity of 20 g h(-1). Furthermore, ozonation enhances the biodegradability of textile wastewater (BOD(5)/COD ratios) by a factor of up to 6.8-fold. A GC-MS analysis of pre-treated textile wastewater showed that some products were present at the end of the pre-treatment time. In spite of this fact, the bacterial luminescence inhibition test (Lumistox test) showed a significant toxicity reduction on comparing the raw and treated textile wastewater. In conclusion, pre-ozonation of textile wastewater is an important step in terms of improving wastewater biodegradability, as well as reducing acute ecotoxicity, which should be removed completely through sequential biological treatment. (c) 2009. Published by Elsevier B.V.

  17. Bioaugmentation efficiency of diesel degradation by Bacillus ...

    African Journals Online (AJOL)

    ... not in sea sand. The study shows that it is critical not only to understand the physiology of the inoculum but also how it affects microbial community structure and function before the microorganism being introduced in the contaminated soil. Key words: Diesel, bioremediation, bioattenuation, bioaugmentation, biostimulation ...

  18. Degradation of CIGS solar cells

    NARCIS (Netherlands)

    Theelen, M.J.

    2015-01-01

    Large scale commercial introduction of CIGS photovoltaics (PV) requires modules with low costs, high efficiencies and long and predictable lifetimes. Unfortunately,knowledge about the lifetime of CIGS PV is limited, which is reflected in the results of field studies: degradation rates varying from

  19. Artificial neural network for on-site quantitative analysis of soils using laser induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    El Haddad, J. [Univ. Bordeaux, LOMA, UMR 5798, F-33400 Talence (France); CNRS, LOMA, UMR 5798, F-33400 Talence (France); Villot-Kadri, M.; Ismaël, A.; Gallou, G. [IVEA Solution, Centre Scientifique d' Orsay, Bât 503, 91400 Orsay (France); Michel, K.; Bruyère, D.; Laperche, V. [BRGM, Service Métrologie, Monitoring et Analyse, 3 avenue Claude Guillemin, B.P 36009, 45060 Orléans Cedex (France); Canioni, L. [Univ. Bordeaux, LOMA, UMR 5798, F-33400 Talence (France); CNRS, LOMA, UMR 5798, F-33400 Talence (France); Bousquet, B., E-mail: bruno.bousquet@u-bordeaux1.fr [Univ. Bordeaux, LOMA, UMR 5798, F-33400 Talence (France); CNRS, LOMA, UMR 5798, F-33400 Talence (France)

    2013-01-01

    Nowadays, due to environmental concerns, fast on-site quantitative analyses of soils are required. Laser induced breakdown spectroscopy is a serious candidate to address this challenge and is especially well suited for multi-elemental analysis of heavy metals. However, saturation and matrix effects prevent from a simple treatment of the LIBS data, namely through a regular calibration curve. This paper details the limits of this approach and consequently emphasizes the advantage of using artificial neural networks well suited for non-linear and multi-variate calibration. This advanced method of data analysis is evaluated in the case of real soil samples and on-site LIBS measurements. The selection of the LIBS data as input data of the network is particularly detailed and finally, resulting errors of prediction lower than 20% for aluminum, calcium, copper and iron demonstrate the good efficiency of the artificial neural networks for on-site quantitative LIBS of soils. - Highlights: ► We perform on-site quantitative LIBS analysis of soil samples. ► We demonstrate that univariate analysis is not convenient. ► We exploit artificial neural networks for LIBS analysis. ► Spectral lines other than the ones from the analyte must be introduced.

  20. Application of micro-solid-phase extraction for the on-site extraction of heterocyclic aromatic amines in seawater.

    Science.gov (United States)

    Basheer, Chanbasha

    2017-12-26

    An efficient on-site extraction technique to determine carcinogenic heterocyclic aromatic amines in seawater has been reported. A micro-solid-phase extraction device placed inside a portable battery-operated pump was used for the on-site extraction of seawater samples. Before on-site applications, parameters that influence the extraction efficiency (extraction time, type of sorbent materials, suitable desorption solvent, desorption time, and sample volume) were investigated and optimized in the laboratory. The developed method was then used for the on-site sampling of heterocyclic aromatic amines determination in seawater samples close to distillation plant. Once the on-site extraction completed, the small extraction device with the analytes was brought back to the laboratory for analysis using high-performance liquid chromatography with fluorescence detection. Based on the optimized conditions, the calibration curves were linear over the concentration range of 0.05-20 μg/L with correlation coefficients up to 0.996. The limits of detection were 0.004-0.026 μg/L, and the reproducibility values were between 1.3 and 7.5%. To evaluate the extraction efficiency, a comparison was made with conventional solid-phase extraction and it was applied to various fortified real seawater samples. The average relative recoveries obtained from the spiked seawater samples varied in the range 79.9-95.2%. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. On-site assessment of environmental and sanitary qualities of ...

    African Journals Online (AJOL)

    On-site assessment of the sanitary location of the RWH system showed that 5% were located near a septic tank and another 5% in flooded area. The harvested rainwater was used for several domestic purposes including drinking. All respondent agreed that they use rainwater for washing while 10% of the respondent ...

  2. 7 CFR 205.403 - On-site inspections.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false On-site inspections. 205.403 Section 205.403 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM...

  3. On-site screening for syphilis at an antenatal clinic

    African Journals Online (AJOL)

    Objective. To determine the validity, predictive value and accuracy of the rapid plasma reagin card test performed on site to diagnose active syphilis in pregnant women so that immediate treatment can be offered to prevent congenital syphilis. Design. Open, descriptive study. Setting. Antenatal clinic, Mamelodi Hospital, ...

  4. Hydrocarbon degradation, plant colonization and gene expression of alkane degradation genes by endophytic Enterobacter ludwigii strains

    Energy Technology Data Exchange (ETDEWEB)

    Yousaf, Sohail [AIT Austrian Institute of Technology GmbH, Bioresources Unit, A-2444 Seibersdorf (Austria); Afzal, Muhammad [AIT Austrian Institute of Technology GmbH, Bioresources Unit, A-2444 Seibersdorf (Austria); National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad (Pakistan); Reichenauer, Thomas G. [AIT Austrian Institute of Technology GmbH, Environmental Resources and Technologies Unit, A-2444 Seibersdorf (Austria); Brady, Carrie L. [Forestry and Agricultural Biotechnology Institute, Department of Microbiology and Plant Pathology, University of Pretoria, Pretoria (South Africa); Sessitsch, Angela, E-mail: angela.sessitsch@ait.ac.at [AIT Austrian Institute of Technology GmbH, Bioresources Unit, A-2444 Seibersdorf (Austria)

    2011-10-15

    The genus Enterobacter comprises a range of beneficial plant-associated bacteria showing plant growth promotion. Enterobacter ludwigii belongs to the Enterobacter cloacae complex and has been reported to include human pathogens but also plant-associated strains with plant beneficial capacities. To assess the role of Enterobacter endophytes in hydrocarbon degradation, plant colonization, abundance and expression of CYP153 genes in different plant compartments, three plant species (Italian ryegrass, birdsfoot trefoil and alfalfa) were grown in sterile soil spiked with 1% diesel and inoculated with three endophytic E. ludwigii strains. Results showed that all strains were capable of hydrocarbon degradation and efficiently colonized the rhizosphere and plant interior. Two strains, ISI10-3 and BRI10-9, showed highest degradation rates of diesel fuel up to 68% and performed best in combination with Italian ryegrass and alfalfa. All strains expressed the CYP153 gene in all plant compartments, indicating an active role in degradation of diesel in association with plants. - Highlights: > E. ludwigii strains efficiently colonized plants in a non-sterile soil environment. > E. ludwigii strains efficiently expressed alkane degradation genes in plants. > E. ludwigii efficiently degraded alkane contaminations and promoted plant growth. > E. ludwigii interacted more effectively with Italian ryegrass than with other plants. > Degradation activity varied with plant and microbial genotype as well as with time. - Enterobacter ludwigii strains belonging to the E. cloacae complex are able to efficiently degrade alkanes when associated with plants and to promote plant growth.

  5. Concentrated Light for Accelerated Photo Degradation of Polymer Materials

    DEFF Research Database (Denmark)

    Madsen, Morten Vesterager; Tromholt, Thomas; Norrman, Kion

    2013-01-01

    Concentrated light is used to perform photochemical degradation of polymer solar cell materials with acceleration factors up to 1200. At constant temperature the photon efficiency in regards to photo degradation is constant for 1–150 suns and oxygen diffusion rates are not a limiting factor....... Accelerated degradation by concentrated light thus allows for rapid and precise evaluations of one sun polymer stabilities....

  6. On-site early-warning system for Bishkek (Kyrgyzstan

    Directory of Open Access Journals (Sweden)

    Dino Bindi

    2015-04-01

    Full Text Available In this work, the development of an on-site early warning system for Bishkek (Kyrgyzstan is outlined. Several low cost sensors equipped with MEMS accelerometers are installed in eight buildings distributed within the urban area. The different sensing units communicate each other via wireless links and the seismic data are streamed in real-time to the data center using internet. Since each single sensing unit has computing capabilities, software for data processing can be installed to perform decentralized actions. In particular, each sensing unit can perform event detection task and run software for on-site early warning. If a description for the vulnerability of the building is uploaded in the sensing unit, this piece of information can be exploited to introduce the expected probability of damage in the early-warning protocol customized for a specific structure.

  7. On-Site Field-Feeding Waste to Energy Converter

    Science.gov (United States)

    2008-12-01

    operator’s duty is to feed relatively dry paper and plastic trash into the OFWEC’s shredder, having previously se- parated cans, glass bottles , and...ON-SITE FIELD- FEEDING WASTE TO ENERGY CONVERTER L. Knowlton* and D. Pickard U.S. Army Natick Soldier Research, Development and Engineering...field- feeding generates tons of solid waste that is a costly logistic burden, requiring personnel, vehi- cles, and fuel that could otherwise be used for

  8. PORTSMOUTH ON-SITE DISPOSAL CELL HIGH DENSITY POLYETHYLENE GEOMEMBRANE LONGEVITY

    Energy Technology Data Exchange (ETDEWEB)

    Phifer, M.

    2012-01-31

    It is anticipated that high density polyethylene (HDPE) geomembranes will be utilized within the liner and closure cap of the proposed On-Site Disposal Cell (OSDC) at the Portsmouth Gaseous Diffusion Plant. The likely longevity (i.e. service life) of HDPE geomembranes in OSDC service is evaluated within the following sections of this report: (1) Section 2.0 provides an overview of HDPE geomembranes, (2) Section 3.0 outlines potential HDPE geomembranes degradation mechanisms, (3) Section 4.0 evaluates the applicability of HDPE geomembrane degradation mechanisms to the Portsmouth OSDC, (4) Section 5.0 provides a discussion of the current state of knowledge relative to the longevity (service life) of HDPE geomembranes, including the relation of this knowledge to the Portsmouth OSDC, and (5) Section 6.0 provides summary and conclusions relative to the anticipated service life of HDPE geomembranes in OSDC service. Based upon this evaluation it is anticipated that the service life of HDPE geomembranes in OSDC service would be significantly greater than the 200 year service life assumed for the OSDC closure cap and liner HDPE geomembranes. That is, a 200 year OSDC HDPE geomembrane service life is considered a conservative assumption.

  9. PEM fuel cell degradation

    Energy Technology Data Exchange (ETDEWEB)

    Borup, Rodney L [Los Alamos National Laboratory; Mukundan, Rangachary [Los Alamos National Laboratory

    2010-01-01

    The durability of PEM fuel cells is a major barrier to the commercialization of these systems for stationary and transportation power applications. While significant progress has been made in understanding degradation mechanisms and improving materials, further improvements in durability are required to meet commercialization targets. Catalyst and electrode durability remains a primary degradation mode, with much work reported on understanding how the catalyst and electrode structure degrades. Accelerated Stress Tests (ASTs) are used to rapidly evaluate component degradation, however the results are sometimes easy, and other times difficult to correlate. Tests that were developed to accelerate degradation of single components are shown to also affect other component's degradation modes. Non-ideal examples of this include ASTs examining catalyst degradation performances losses due to catalyst degradation do not always well correlate with catalyst surface area and also lead to losses in mass transport.

  10. Mechanistic study of a diazo dye degradation by Soybean Peroxidase

    OpenAIRE

    Kalsoom, Umme; Ashraf, Syed Salman; Meetani, Mohammed A; Rauf, Muhammad A; Bhatti, Haq Nawaz

    2013-01-01

    Background Enzyme based remediation of wastewater is emerging as a novel, efficient and environmentally-friendlier approach. However, studies showing detailed mechanisms of enzyme mediated degradation of organic pollutants are not widely published. Results The present report describes a detailed study on the use of Soybean Peroxidase to efficiently degrade Trypan Blue, a diazo dye. In addition to examining various parameters that can affect the dye degradation ability of the enzyme, such as e...

  11. The On-Site Analysis of the Cherenkov Telescope Array

    CERN Document Server

    Bulgarelli, Andrea; Zoli, Andrea; Aboudan, Alessio; Rodríguez-Vázquez, Juan José; De Cesare, Giovanni; De Rosa, Adriano; Maier, Gernot; Lyard, Etienne; Bastieri, Denis; Lombardi, Saverio; Tosti, Gino; Bergamaschi, Sonia; Beneventano, Domenico; Lamanna, Giovanni; Jacquemier, Jean; Kosack, Karl; Antonelli, Lucio Angelo; Boisson, Catherine; Borkowski, Jerzy; Buson, Sara; Carosi, Alessandro; Conforti, Vito; Colomé, Pep; Reyes, Raquel de los; Dumm, Jon; Evans, Phil; Fortson, Lucy; Fuessling, Matthias; Gotz, Diego; Graciani, Ricardo; Gianotti, Fulvio; Grandi, Paola; Hinton, Jim; Humensky, Brian; Inoue, Susumu; Knödlseder, Jürgen; Flour, Thierry Le; Lindemann, Rico; Malaguti, Giuseppe; Markoff, Sera; Marisaldi, Martino; Neyroud, Nadine; Nicastro, Luciano; Ohm, Stefan; Osborne, Julian; Oya, Igor; Rodriguez, Jerome; Rosen, Simon; Ribo, Marc; Tacchini, Alessandro; Schüssler, Fabian; Stolarczyk, Thierry; Torresi, Eleonora; Testa, Vincenzo; Wegner, Peter

    2015-01-01

    The Cherenkov Telescope Array (CTA) observatory will be one of the largest ground-based very high-energy gamma-ray observatories. The On-Site Analysis will be the first CTA scientific analysis of data acquired from the array of telescopes, in both northern and southern sites. The On-Site Analysis will have two pipelines: the Level-A pipeline (also known as Real-Time Analysis, RTA) and the level-B one. The RTA performs data quality monitoring and must be able to issue automated alerts on variable and transient astrophysical sources within 30 seconds from the last acquired Cherenkov event that contributes to the alert, with a sensitivity not worse than the one achieved by the final pipeline by more than a factor of 3. The Level-B Analysis has a better sensitivity (not be worse than the final one by a factor of 2) and the results should be available within 10 hours from the acquisition of the data: for this reason this analysis could be performed at the end of an observation or next morning. The latency (in part...

  12. Portable Infrared Laser Spectroscopy for On-site Mycotoxin Analysis

    Science.gov (United States)

    Sieger, Markus; Kos, Gregor; Sulyok, Michael; Godejohann, Matthias; Krska, Rudolf; Mizaikoff, Boris

    2017-03-01

    Mycotoxins are toxic secondary metabolites of fungi that spoil food, and severely impact human health (e.g., causing cancer). Therefore, the rapid determination of mycotoxin contamination including deoxynivalenol and aflatoxin B1 in food and feed samples is of prime interest for commodity importers and processors. While chromatography-based techniques are well established in laboratory environments, only very few (i.e., mostly immunochemical) techniques exist enabling direct on-site analysis for traders and manufacturers. In this study, we present MYCOSPEC - an innovative approach for spectroscopic mycotoxin contamination analysis at EU regulatory limits for the first time utilizing mid-infrared tunable quantum cascade laser (QCL) spectroscopy. This analysis technique facilitates on-site mycotoxin analysis by combining QCL technology with GaAs/AlGaAs thin-film waveguides. Multivariate data mining strategies (i.e., principal component analysis) enabled the classification of deoxynivalenol-contaminated maize and wheat samples, and of aflatoxin B1 affected peanuts at EU regulatory limits of 1250 μg kg-1 and 8 μg kg-1, respectively.

  13. Laboratory and On-Site Tests for Rapid Runway Repair

    Directory of Open Access Journals (Sweden)

    Federico Leonelli

    2017-11-01

    Full Text Available The attention to rapid pavement repair has grown fast in recent decades: this topic is strategic for the airport management process for civil purposes and peacekeeping missions. This work presents the results of laboratory and on-site tests for rapid runway repair, in order to analyse and compare technical and mechanical performances of 12 different materials currently used in airport. The study focuses on site repairs, a technique adopted most frequently than repairs with modular elements. After describing mechanical and physical properties of the examined materials (2 bituminous emulsions, 5 cement mortars, 4 cold bituminous mixtures and 1 expanding resin, the study presents the results of carried out mechanical tests. The results demonstrate that the best performing material is a one-component fast setting and hardening cement mortar with graded aggregates. This material allows the runway reopening 6 h after the work. A cold bituminous mixture (bicomponent premixed cold asphalt with water as catalyst and the ordinary cement concrete allow the reopening to traffic after 18 h, but both ensure a lower service life (1000 coverages than the cement mortar (10,000 coverages. The obtained results include important information both laboratory level and field, and they could be used by airport management bodies and road agencies when scheduling and evaluating pavement repairs.

  14. Genetic construction of PCB degraders.

    Science.gov (United States)

    Brenner, V; Arensdorf, J J; Focht, D D

    1994-12-01

    Genetic construction of recombinant strains with expanded degradative abilities may be useful for bioremedation of recalcitrant compounds, such as polychlorinated biphenyls (PCBs). Some degradative genes have been found either on conjugative plasmids or on transposons, which would facilitate their genetic transfer. The catabolic pathway for the total degradation of PCBs is encoded by two different sets of genes that are not normally found in the same organism. The bphABCD genes normally reside on the chromosome and encode for the four enzymes involved in the production of benzoate and chlorobenzoates from the respective catabolism of biphenyl and chlorobiphenyls. The genes encoding for chlorobenzoate catabolism have been found on both plasmids and the chromosome, often in association with transposable elements. Ring fission of chlorobiphenyls and chlorobenzoates involves the meta-fission pathway (3-phenylcatechol 2,3-dioxygenase) and the ortho-fission pathway (chlorocatechol 1,2-dioxygenase), respectively. As the catecholic intermediates of both pathways are frequently inhibitory to each other, incompatibilities result. Presently, all hybrid strains constructed by in vivo matings metabolize simple chlorobiphenyls through complementary pathways by comprising the bph, benzoate, and chlorocatechol genes of parental strains. No strains have yet been verified which are able to utilize PCBs having at least one chlorine on each ring as growth substrates. The possible incompatibilities of hybrid pathways are evaluated with respect to product toxicity, and the efficiency of both in vivo and in vitro genetic methods for the construction of recombinant strains able to degrade PCBs is discussed.

  15. Recent land degradation and improvement in China.

    Science.gov (United States)

    Bai, Zhanguo; Dent, David

    2009-05-01

    Land degradation is a global development and environment issue that afflicts China more than most countries in terms of the extent, economic impact, and number of people affected. Up-to-date, quantitative information is needed to support policy and action for food and water security, economic development, and environmental integrity. Data for a defined, recent period enable us to distinguish the legacy of historical land degradation from what is happening now. We define land degradation as long-term decline in ecosystem function and productivity and measure it by remote sensing of the normalized difference vegetation index (NDVI), the greenness index. NDVI may be translated to net primary productivity (NPP). Deviation from the norm serves as a proxy assessment of land degradation and improvement-if other factors that may be responsible are taken into account. These other factors include climate, which may be assessed by rain-use efficiency and energy-use efficiency. Analysis of the 23-year Global Inventory Modeling and Mapping Studies (GIMMS) NDVI data reveals that, in China over the period 1981-2003, NPP increased overall, but areas of declining climate-adjusted NPP comprise 23% of the country, mainly in south China. About 35% of China's population (457 million out of 1317 million) depend on the degrading land. Degrading areas suffered a loss of NPP of 12 kgC ha(-1) y(-1), amounting to almost 60 million tC not fixed from the atmosphere; loss of soil organic carbon from these areas is likely to be orders of magnitude greater. There is no correlation between land degradation and dry lands; it is more of an issue in cropland and forest: 21% of degrading land is cropland and 40% is forest, 24% of the arable and 44% of the forest, respectively. There is no simple statistical relationship between land degradation and rural population density or poverty. Most identified land degradation is in the south and east, driven by unprecedented land-use change.

  16. Comparative analysis of effluent water quality from a municipal treatment plant and two on-site wastewater treatment systems.

    Science.gov (United States)

    Garcia, Santos N; Clubbs, Rebekah L; Stanley, Jacob K; Scheffe, Brian; Yelderman, Joe C; Brooks, Bryan W

    2013-06-01

    Though decentralized on-site technologies are extensively employed for wastewater treatment around the globe, an understanding of effluent water quality impairments associated with these systems remain less understood than effluent discharges from centralized municipal wastewater treatment facilities. Using a unique experimental facility, a novel comparative analysis of effluent water quality was performed from model decentralized aerobic (ATS) and septic (STS) on-site wastewater treatment systems and a centralized municipal wastewater treatment plant (MTP). The ATS and STS units did not benefit from further soil treatment. Each system received common influent wastewater from the Waco, Texas, USA Metropolitan Area Regional Sewerage System. We tested the hypothesis that MTP effluent would exhibit higher water quality than on-site effluents, based on parameters selected for study. A tiered testing approach was employed to assess the three effluent discharges: select routine water quality parameters (Tier I), whole effluent toxicity (Tier II), and select endocrine-active compounds (Tier III). Contrary to our hypothesis, ATS effluent was not statistically different from MTP effluents, based on Tier I and III parameters, but reproductive responses of Daphnia magna were slightly more sensitive to ATS than MTP effluents. STS effluent water quality was identified as most degraded of the three wastewater treatment systems. Parameters used to assess centralized wastewater treatment plant effluent water quality such as whole effluent toxicity and endocrine active substances appear useful for water quality assessments of decentralized discharges. Aerobic on-site wastewater treatment systems may represent more robust options than traditional septic systems for on-site wastewater treatment in watersheds with appreciable groundwater - surface water exchange. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Ash cap influences on site productivity and fertilizer response in forests of the Inland Northwest

    Science.gov (United States)

    Mariann T. Garrison-Johnston; Peter G. Mika; Dan L. Miller; Phil Cannon; Leonard R. Johnson

    2007-01-01

    Data from 139 research sites throughout the Inland Northwest were analyzed for effects of ash cap on site productivity, nutrient availability and fertilization response. Stand productivity and nitrogen (N) fertilizer response were greater on sites with ash cap than on sites without. Where ash was present, depth of ash had no effect on site productivity or N fertilizer...

  18. The Influence of Seismic Parameters on Site Response

    Directory of Open Access Journals (Sweden)

    Asakereh A.

    2015-09-01

    Full Text Available Geotechnical earthquake engineers have been trying to determine the most appropriate solution techniques for ground response analysis under earthquake loadings. This paper presents the importance of the adequate soil behavior model to simulate earthquake site response analysis. The influence of nonlinearity and linearity of soils on the site response is also investigated. Many methods have been proposed for the analysis of one-dimensional ground response such as nonlinear methods and equivalent linear with reduced modulus. Using 13 well known earthquake records and geotechnical information of sand in the Qeshm Island (Iran and classification of earthquakes based on seismic parameters, the influence of each parameter on the Response spectra and Fourier Spectrum of surface of ground becomes evident. Analysis was done using two softwares; EERA (equivalent linear analysis and NERA (nonlinear analysis and compared. Finally, output of the software is compared with the reference result on site.

  19. Electrochemical microdevice for on-site determination of rice freshness.

    Science.gov (United States)

    Koyachi, Eri; Kojima, Kenichi; Qiu, Xiaoli; Satake, Takaaki; Suzuki, Hiroaki

    2013-04-15

    An electrochemical microdevice was fabricated for on-site rapid freshness determination of rice. The activity of peroxidase was used as an indicator for freshness. With hydrogen peroxide and hydroquinone as substrates, the enzymatic reaction of peroxidase produced benzoquinone, which was subsequently reduced on a gold working electrode electrochemically. The progress of the enzymatic reaction could clearly be observed in the change of cyclic voltammograms. Distinct differences were observed in the current change between fresh rice and aged rice, reflecting the remaining activity of peroxide. The current also depended on the time at which rice grains were milled. The result agreed well with those obtained by the conventional fluorometric and guaiacol methods. Comparison of results obtained with different numbers of grains showed that even the measurement with a single grain provided fairly consistent data. Furthermore, the existence of grains of different freshness could be identified using a device with multiple sensing sites. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Greenhouse gas emissions from on-site wastewater treatment systems

    Science.gov (United States)

    Somlai-Haase, Celia; Knappe, Jan; Gill, Laurence

    2016-04-01

    Nearly one third of the Irish population relies on decentralized domestic wastewater treatment systems which involve the discharge of effluent into the soil via a percolation area (drain field). In such systems, wastewater from single households is initially treated on-site either by a septic tank and an additional packaged secondary treatment unit, in which the influent organic matter is converted into carbon dioxide (CO2) and methane (CH4) by microbial mediated processes. The effluent from the tanks is released into the soil for further treatment in the unsaturated zone where additional CO2 and CH4 are emitted to the atmosphere as well as nitrous oxide (N2O) from the partial denitrification of nitrate. Hence, considering the large number of on-site systems in Ireland and internationally, these are potential significant sources of greenhouse gas (GHG) emissions, and yet have received almost no direct field measurement. Here we present the first attempt to quantify and qualify the production and emissions of GHGs from a septic tank system serving a single house in the County Westmeath, Ireland. We have sampled the water for dissolved CO2, CH4 and N2O and measured the gas flux from the water surface in the septic tank. We have also carried out long-term flux measurements of CO2 from the drain field, using an automated soil gas flux system (LI-8100A, Li-Cor®) covering a whole year semi-continuously. This has enabled the CO2 emissions from the unsaturated zone to be correlated against different meteorological parameters over an annual cycle. In addition, we have integrated an ultraportable GHG analyser (UGGA, Los Gatos Research Inc.) into the automated soil gas flux system to measure CH4 flux. Further, manual sampling has also provided a better understanding of N2O emissions from the septic tank system.

  1. A business case for on-site generation: The BD biosciences pharmingen project

    Energy Technology Data Exchange (ETDEWEB)

    Firestone, Ryan; Creighton, Charles; Bailey, Owen; Marnay, Chris; Stadler, Michael

    2003-09-01

    Deregulation is haltingly changing the United States electricity markets. The resulting uncertainty and/or rising energy costs can be hedged by generating electricity on-site and other benefits, such as use of otherwise wasted heat, can be captured. The Public Utility Regulatory Policy Act (PURPA) of 1978 first invited relatively small-scale generators ({ge} 1 MW) into the electricity market. The advent of efficient and reliable small scale and renewable equipment has spurred an industry that has, in recent years, made even smaller (business scale) electricity generation an economically viable option for some consumers. On-site energy capture and/or conversion, known as distributed energy resources (DER), offers consumers many benefits, such as economic savings and price predictability, improved reliability, control over power quality, and emissions reductions. Despite these benefits, DER adoption can be a daunting move to a customer accustomed to simply paying a monthly utility bill. San Diego is in many ways an attractive location for DER development: It has high electricity prices typical of California and a moderate climate i.e. energy loads are consistent throughout the year. Additionally, the price shock to San Diego Gas and Electric (SDG&E) customers during the summer of 2000 has interested many in alternatives to electricity price vulnerability. This report examines the business case for DER at the San Diego biotechnology supply company, BD Biosciences Pharmingen, which considered DER for a building with 200-300 kW base-load, much of which accommodates the refrigerators required to maintain chemicals. Because of the Mediterranean climate of the San Diego area and the high rate of air changes required due to on-site use of chemicals, modest space heating is required throughout the year. Employees work in the building during normal weekday business hours, and daily peak loads are typically about 500 kW.

  2. Screening for distinct xylan degrading enzymes in complex shake flask fermentation supernatants

    NARCIS (Netherlands)

    Gool, van M.P.; Vansco, I.; Schols, H.A.; Toth, K.; Szakacs, G.; Gruppen, H.

    2011-01-01

    The efficient degradation of complex xylans needs collaboration of many xylan degrading enzymes. Assays for xylan degrading activities based on reducing sugars or PNP substrates are not indicative for the presence of enzymes able to degrade complex xylans: They do not provide insight into the

  3. Mechanisms of humic substances degradation by fungi

    Science.gov (United States)

    Chen, Y.; Hadar, Y.; Grinhut, T.

    2012-04-01

    Humic substances (HS) are formed by secondary synthesis reactions (humification) during the decay process and transformation of biomolecules originating from plants and other dead organisms. In nature, HS are extremely resistant to biological degradation. Thus, these substances are major components in the C cycle and in the biosphere and therefore, the understanding of the process leading to their formation and transformation and degradation is vital. Fungi active in the decomposition process of HS include mainly ascomycetes and basidiomycetes that are common in the upper layer of forest and grassland soils. Many basidiomycetes belong to the white-rot fungi (WRF) and litter-decomposing fungi (LDF). These fungi are considered to be the most efficient lignin degraders due to their nonspecific oxidizing enzymes: manganese peroxidase (MnP), lignin peroxidase (LiP) and laccase. Although bacteria dominate compost and participate in the turnover of HS, their ability to degrade stable macromolecules such as lignin and HS is limited. The overall objectives of this research were to corroborate biodegradation processes of HS by WRF. The specific objectives were: (i) To isolate, identify and characterize HS degrading WRF from biosolids (BS) compost; (ii) To study the biodegradation process of three types of HS, which differ in their structure, by WRF isolated from BS compost; and (iii) To investigate the mechanisms of HA degradation by WRF using two main approaches: (a) Study the physical and chemical analyses of the organic compounds obtained from direct fungal degradation of HA as well as elucidation of the relevant enzymatic reactions; and (b) Study the enzymatic and biochemical mechanisms involved during HA degradation. In order to study the capability of fungi to degrade HS, seventy fungal strains were isolated from biosolids (BS) compost. Two of the most active fungal species were identified based on rDNA sequences and designated Trametes sp. M23 and Phanerochaetesp., Y6

  4. Bacterial Degradation of Pesticides

    DEFF Research Database (Denmark)

    Knudsen, Berith Elkær

    . Bioaugmentation i.e. addition of specific degrader organisms, has been suggested as an environmentally friendly and economically competitive strategy for cleaning polluted sites. Several organisms have been isolated, capable of degrading different compounds. However the capacity to degrade the desired compound...... SRS2, Variovorax SRS16 and Arthrobacter globiformis D47. The degradation capacity of each strain individually as well as two- and three-member consortia was studied in a sand column set up. Glass beads were added to the set up to create a dry patch, separating the organisms and the diuron-spiked sand...

  5. Recycling of treated domestic effluent from an on-site wastewater treatment system for hydroponics.

    Science.gov (United States)

    Oyama, N; Nair, J; Ho, G E

    2005-01-01

    An alternative method to conserve water and produce crops in arid regions is through hydroponics. Application of treated wastewater for hydroponics will help in stripping off nutrients from wastewater, maximising reuse through reduced evaporation losses, increasing control on quality of water and reducing risk of pathogen contamination. This study focuses on the efficiency of treated wastewater from an on-site aerobic wastewater treatment unit. The experiment aimed to investigate 1) nutrient reduction 2) microbial reduction and 3) growth rate of plants fed on wastewater compared to a commercial hydroponics medium. The study revealed that the chemical and microbial quality of wastewater after hydroponics was safe and satisfactory for irrigation and plant growth rate in wastewater hydroponics was similar to those grown in a commercial medium.

  6. Efficiency of Cu{sub 2}O/BiVO{sub 4} particles prepared with a new soft procedure on the degradation of dyes under visible-light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Aguilera-Ruiz, Eduardo [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Centro de Investigación e Innovación en Ingeniería Aeronáutica, Carretera a Salinas Victoria, Km 2.3, 66600 Apodaca, NL (Mexico); García-Pérez, Ulises M., E-mail: ulisesma.garcia@gmail.com [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Centro de Investigación e Innovación en Ingeniería Aeronáutica, Carretera a Salinas Victoria, Km 2.3, 66600 Apodaca, NL (Mexico); Garza-Galván, María de la; Zambrano-Robledo, Patricia; Bermúdez-Reyes, Bárbara [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Centro de Investigación e Innovación en Ingeniería Aeronáutica, Carretera a Salinas Victoria, Km 2.3, 66600 Apodaca, NL (Mexico); and others

    2015-02-15

    Graphical abstract: - Highlights: • Cu{sub 2}O/BiVO{sub 4} p–n heterojunctions were synthesized by a simple impregnation method. • The photocatalytic performance was evaluated using a LED lamp as visible source. • The composite with 1 wt.% of Cu{sub 2}O exhibits the best visible-light-activity. • A mechanism for the carriers transfer is proposed. • Factors as pH and O{sub 2} were found to influence the degradation rate. - Abstract: Cu{sub 2}O/BiVO{sub 4} composites with different concentrations of Cu{sub 2}O were synthesized by a simple impregnation method at 200 °C under N{sub 2} atmosphere for 4 h. The as-synthesized samples were characterized by X-ray powder diffraction, scanning electron microscopy, UV–vis diffuse reflection absorption and vis photoluminescence. The morphology of the as-synthesized composites with different weight ratios of Cu{sub 2}O is composed by quasi-spherical and dendrite-like particles. The photocatalytic performance of the Cu{sub 2}O/BiVO{sub 4} composites was evaluated by degradation of methyl orange solutions under visible-LED irradiation. The results obtained show that the photocatalytic behavior of the p–n heterojunction Cu{sub 2}O/BiVO{sub 4} composites was better than pure Cu{sub 2}O and BiVO{sub 4}. The variation of the reaction parameters, such as solution pH and presence of O{sub 2}, improved the photocatalytic performance of Cu{sub 2}O/BiVO{sub 4} composite. Meanwhile, a possible mechanism for methyl orange photocatalytic degradation over Cu{sub 2}O/BiVO{sub 4} photocatalysts was proposed. The chemical stability and reusability of Cu{sub 2}O/BiVO{sub 4} powders were also investigated.

  7. An On-Site Presentation of Invisible Prehistoric Landscapes

    Directory of Open Access Journals (Sweden)

    Jiri Unger

    2017-03-01

    Full Text Available The rapid development of information technology has enabled the creation of entirely new presentation frameworks and this article will attempt to explore the subject of on-site presentation of archaeological sites. The most frequently used environment currently has been in the form of a variety of virtual museums that are accessible on the Internet; in essence these keep their visitors stuck in front of a PC monitor. One option that allows leaving the monitor and stepping directly out-of-doors into a virtual open-air museum is by means of applications for mobile phones. Terms such as 'virtual' or 'augmented reality' no longer represent a million light-years away science-fiction concepts, but rather a new tool for public archaeology and for the preservation of the archaeological heritage. This article presents several projects that have been implemented by the Archaeological Institute in Prague, who, by using mobile applications, built virtual open-air museums directly in the locations of archaeological excavations.

  8. SCC and conventional concrete on site: property assessment

    Directory of Open Access Journals (Sweden)

    S. Nunes

    Full Text Available The present paper deals with comparing properties of hardened SCC cast during first full-scale tests in a precast factory and similar conventional concrete currently used in the same factory. The main goal was to evaluate viability of replacing the C45/55 conventional concrete, in use at the precast factory, by a SCC of the same class of resistance and maintaining the constituent materials. A wide number of specimens (cubes, cylinders, prisms and full size precast elements were cast with both SCC and conventional vibrated concrete to enable comparing different properties of both types of hardened concrete. In order to implement SCC in this precast factory, suitability of actual current processes involved in production, mixing, transport and placing had to be evaluated. SCC exhibited improved mechanical behavior, higher resistance to fluid ingress and a more uniform strength along the full-size element due to a combination of proper mixdesign together with controlled mixing and placing on site.

  9. Benefits of On-Site Management of Environmental Restoration Wastes

    Energy Technology Data Exchange (ETDEWEB)

    Irwin, Michael J. ,P.E.; Wood, Craig, R.E.M.; Kwiecinski, Daniel, P.E.; Alanis, Saul

    2003-02-27

    As Sandia National Laboratories/New Mexico (SNL/NM) began assessing options under which to conduct the remediation of environmental restoration sites, it became clear that the standard routes for permanent disposal of waste contaminated with hazardous materials would be difficult. Publicly, local citizens' groups resisted the idea of large volumes of hazardous waste being transported through their communities. Regulations for the off-site disposal are complicated due to the nature of the environmental restoration waste, which included elevated tritium levels. Waste generated from environmental restoration at SNL/NM included debris and soils contaminated with a variety of constituents. Operationally, disposal of environmental restoration waste was difficult because of the everchanging types of waste generated during site remediation. As an alternative to standard hazardous waste disposal, SNL/NM proposed and received regulatory approval to construct a Corrective Action Management Unit (CAMU). By containing the remediation wastes on-site, SNL/NM's Environmental Restoration (ER) Program managed to eliminate transportation concerns from the public, worked with regulatory agencies to develop a safe, permanent disposal, and modified the waste disposal procedures to accommodate operational changes. SNL/NM accomplished the task and saved approximately $200 million over the life of the CAMU project, as compared to off-site disposal options.

  10. Freeze-dried recombinant bacteria for on-site detection of phenolic compounds by color change.

    Science.gov (United States)

    Shin, Hae Ja; Park, Hoo Hwi; Lim, Woon Ki

    2005-09-22

    We herein report the development of a recombinant bacterial biosensor for the rapid and easy detection of phenolic compounds in the field. A plasmid was designed to encode a beta-galactosidase reporter gene under the control of capR, an activator involved in phenolic compound degradation. The construct was transformed into Escherichia coli, and transformed cells were stored after being freeze-dried in the presence of sucrose. For detection of phenolic compounds, the cells were rehydrated, and used instantly, without any growth step. In the presence of 0.1 microM-10mM phenol, we observed a red color from hydrolysis of chlorophenol red beta-D-galactopyranoside (CPRG) or an indigo color from hydrolysis of X-galactopyranoside (X-gal). Other phenolic compounds could be detected by this system, including catechol, 2-methylphenol, 2-chlorophenol, 3-methylphenol, 2-nitrophenol, and 4-chlorophenol. These results suggest that this novel bacteria biosensor may be useful for easy, on-site detection of phenolic compounds without the need for unwieldy equipment or sample pretreatment. Indeed, biosensor systems involving beta-galactosidase-expressing freeze-dried recombinant bacteria could prove useful for the in situ detection of many more compounds in the future.

  11. Heterogeneous photocatalytic degradation of monochlorobenzene in water.

    Science.gov (United States)

    Huang, Hsin-Hsu; Tseng, Dyi-Hwa; Juang, Lain-Chuen

    2008-08-15

    This investigation evaluated the photocatalytic degradation of monochlorobenzene (MCB) in an aqueous TiO(2) suspension. In accordance with the experimental results, the degradation of MCB was a function of the initial substrate concentration, incident light intensity, and TiO(2) dosage. However, the solution pH had insignificant effect on the degradation efficiency. The heterogeneous photocatalytic degradation of MCB followed the Langmuir-Hinshelwood kinetics. The adsorption coefficient of MCB (K) and the observed degradation rate constant (k) were calculated as 13.4 mM(-1) and 0.0054 mM min(-1), respectively. In addition, a 0.255 dependency of the initial degradation rate on the light intensity revealed the considerable adverse effect of e(-)-h(+) pair recombination. Both mineralization and dechlorination occurred during the photocatalytic degradation of MCB. Under the operating condition of initial MCB concentration of 0.1mM, light intensity of 5.68 microEinsteins(-1), TiO(2) dosage of 1.0 g L(-1), and solution pH of 7, about 93.7% of MCB was mineralized after 240 min of irradiation. Nevertheless, 64.3% of the stoichiometric amount of Cl(-) ions was released into the bulk solution. The simulation results derived from the X-ray photoelectron spectroscopy (XPS) analysis was suggested that the interaction between Cl(-) ions and TiO(2) surface tended to lower the released amount of Cl(-) ions.

  12. Degradation of polyvinyl alcohol (PVA) by UV/chlorine oxidation: Radical roles, influencing factors, and degradation pathway.

    Science.gov (United States)

    Ye, Bei; Li, Yue; Chen, Zhuo; Wu, Qian-Yuan; Wang, Wen-Long; Wang, Ting; Hu, Hong-Ying

    2017-11-01

    Polyvinyl alcohol (PVA) is widely used in industry but is difficult to degrade. In this study, the synergistic effect of UV irradiation and chlorination on degradation of PVA was investigated. UV irradiation or chlorination alone did not degrade PVA. By contrast, UV/chlorine oxidation showed good efficiency for PVA degradation via generation of active free radicals, such as OH and Cl. The relative importance of these two free radicals in the oxidation process was evaluated, and it was shown that OH contributed more to PVA degradation than Cl did. The degradation of PVA followed pseudo first order kinetics. The rate constant k increased linearly from 0 min-1 to 0.3 min-1 with increasing chlorine dosage in range of 0 mg/L to 20 mg/L. However, when the chlorine dosage was increased above 20 mg/L, scavenging effect of free radicals occurred, and the degradation efficiency of PVA did not increase much more. Acidic media increased the degradation efficiency of PVA by UV/chlorine oxidation more than basic or neutral media because of the higher ratio of [HOCl]/[OCl-], higher free radical quantum yields, and the lower free radical quenching effect under acidic conditions. Results of Fourier Transform Infrared Spectroscopy showed that carbonyl groups in degradation products were formed during UV/chlorine oxidation, and a possible degradation pathway via alcohol to carbonyl was proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Highly-efficient photocatalytic degradation of methylene blue by PoPD-modified TiO2nanocomposites due to photosensitization-synergetic effect of TiO2with PoPD.

    Science.gov (United States)

    Yang, Chuanxi; Dong, Wenping; Cui, Guanwei; Zhao, Yingqiang; Shi, Xifeng; Xia, Xinyuan; Tang, Bo; Wang, Weiliang

    2017-06-21

    Poly-o-phenylenediamine modified TiO 2 nanocomposites were successfully synthesized via an 'in situ' oxidative polymerization method. The modified nanocomposites were characterized by BET, XRD, TEM, FT-IR, TGA, XPS, EA and UV-Vis DRS. The photocatalytic degradation of methylene blue was chosen as a model reaction to evaluate the photocatalytic activities of TiO 2 and PoPD/TiO 2 . The results indicated that PoPD/TiO 2 nanocomposites exhibited good photocatalytic activity and stability. The photocatalytic activity of PoPD/TiO 2 increased as the initial pH increased because of electrostatic adsorption between the photocatalyst and MB as well as the generation of ·OH, whereas it exhibited an earlier increasing and later decreasing trend as the concentration of the photocatalyst increased owing to the absorption of visible light. The photocatalytic stability of the PoPD/TiO 2 nanocomposite was dependent on the stability of its structure. Based on radical trapping experiments and ESR measurements, the origin of oxidizing ability of PoPD/TiO 2 nanocomposites on photocatalytic degradation of MB was proposed, which taking into account of ·OH and ·O 2 - were the first and second important ROS, respectively. The possible photocatalytic mechanism and photocatalytic activity enhanced mechanism has been proposed, taking into account the photosensitization effect and synergetic effect of TiO 2 with PoPD.

  14. 76 FR 43349 - General Motors Corporation, Renaissance Center, including On-Site Leased Workers From Accretive...

    Science.gov (United States)

    2011-07-20

    ... Employment and Training Administration General Motors Corporation, Renaissance Center, including On-Site... 23, 2010, applicable to workers of General Motors Corporation, Renaissance Center, including on-site... Detroit, Michigan location of General Motors Corporation, Renaissance Center. The Department has...

  15. International Symposium on Site Characterization for CO2Geological Storage

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, Chin-Fu

    2006-02-23

    Several technological options have been proposed to stabilize atmospheric concentrations of CO{sub 2}. One proposed remedy is to separate and capture CO{sub 2} from fossil-fuel power plants and other stationary industrial sources and to inject the CO{sub 2} into deep subsurface formations for long-term storage and sequestration. Characterization of geologic formations for sequestration of large quantities of CO{sub 2} needs to be carefully considered to ensure that sites are suitable for long-term storage and that there will be no adverse impacts to human health or the environment. The Intergovernmental Panel on Climate Change (IPCC) Special Report on Carbon Dioxide Capture and Storage (Final Draft, October 2005) states that ''Site characterization, selection and performance prediction are crucial for successful geological storage. Before selecting a site, the geological setting must be characterized to determine if the overlying cap rock will provide an effective seal, if there is a sufficiently voluminous and permeable storage formation, and whether any abandoned or active wells will compromise the integrity of the seal. Moreover, the availability of good site characterization data is critical for the reliability of models''. This International Symposium on Site Characterization for CO{sub 2} Geological Storage (CO2SC) addresses the particular issue of site characterization and site selection related to the geologic storage of carbon dioxide. Presentations and discussions cover the various aspects associated with characterization and selection of potential CO{sub 2} storage sites, with emphasis on advances in process understanding, development of measurement methods, identification of key site features and parameters, site characterization strategies, and case studies.

  16. Photocatalytic efficiency of Fe2O3/TiO2for the degradation of typical dyes in textile industries: Effects of calcination temperature and UV-assisted thermal synthesis.

    Science.gov (United States)

    Nasirian, Mohsen; Bustillo-Lecompte, Ciro Fernando; Mehrvar, Mehrab

    2017-07-01

    The inadequate management practices in industrial textile effluents have a considerable negative impact on the environment and human health due to the indiscriminate release of dyes. Photocatalysis is one of the diverse advance oxidation processes (AOPs) and titanium dioxide (TiO 2 ) is recognized for its high oxidation and reduction power. A composite photocatalyst of Fe 2 O 3 /TiO 2 is synthesized using different mass ratios of Fe:TiO 2 to improve its photoactivity. The composite photocatalyst is calcined at 300-900 °C. Their photocatalytic activity for the degradation of Congo red (CR) and methyl orange (MO) is investigated by total organic carbon (TOC) analysis. The formation and characterization of the as-prepared composite are studied by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS). The effect of calcination temperature on the composite Fe 2 O 3 /TiO 2 photocatalyst is investigated using Fourier transform infrared spectroscopy (FTIR). The photocatalytic activity and the phase conversion are studied by X-ray diffraction (XRD). The specific surface area of photocatalysts at different calcination temperatures is investigated based on Brunauer-Emmett-Teller (BET) surface area analysis. Results show that at an optimum calcination temperature of 300 °C for the photocatalyst preparation, the specific surface area is maximum and the photocatalyst has the highest photoactivity. Thus, the degradation of organic materials reaches 62.0% for MO and 46.8% for CR in the presence of Fe 2 O 3 /TiO 2 (0.01 w:w Fe:TiO 2 ) calcined at 300 °C with the highest specific surface area (98.73 m 2 /g). The transformation of TiO 2 from anatase to rutile is facilitated by high temperature and high concentration of iron while high crystallization and particle size increase occur. An optimum calcination temperature of 300 °C is found at which the degradation of typical dyes in textile industries is maximum. Copyright © 2017 Elsevier

  17. One-pot approach for synthesis of N-doped TiO{sub 2}/ZnFe{sub 2}O{sub 4} hybrid as an efficient photocatalyst for degradation of aqueous organic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Yunjin, E-mail: yaoyunjin@gmail.com [Anhui Key Lab of Controllable Chemical Reaction & Material Chemical Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Tunxi Road 193, Hefei 230009 (China); State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing University of Technology, Nanjing 210009 (China); School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui 230026 (China); Qin, Jiacheng; Chen, Hao; Wei, Fengyu; Liu, Xueting; Wang, Jianlong [Anhui Key Lab of Controllable Chemical Reaction & Material Chemical Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Tunxi Road 193, Hefei 230009 (China); Wang, Shaobin, E-mail: shaobin.wang@curtin.edu.au [Department of Chemical Engineering, Curtin University, G.P.O. Box U1987, Perth, Western Australia 6845 (Australia)

    2015-06-30

    Highlights: • N-doped TiO{sub 2}/ZnFe{sub 2}O{sub 4} catalysts were prepared by a one-pot vapor-thermal method. • The UV–vis-light-driven photocatalytic activities of the hybrids were evaluated. • Influence factor, degradation kinetics, and mechanism, have been analyzed. • Active species in the degradation process were detected by using the scavengers. • N-doped TiO{sub 2}/ZnFe{sub 2}O{sub 4} showed to be a promising catalyst and simple separation. - Abstract: N-doped TiO{sub 2}/ZnFe{sub 2}O{sub 4} catalysts were successfully prepared by coupling nitrogen modified TiO{sub 2} with ZnFe{sub 2}O{sub 4} via a one-pot vapor-thermal method. The physicochemical properties of the as-prepared catalysts have been characterized using various spectroscopic and microscopic techniques. The UV–vis-light-driven photocatalytic activities of the hybrids were evaluated and the effects of the amount of photocatalyst, different types of dyes, catalyst stability on photodegradation of organic dyes were investigated. Moreover, degradation kinetics and mechanism as well as the roles of N doping, ZnFe{sub 2}O{sub 4} and TiO{sub 2} have been analyzed. It was revealed that N-doped TiO{sub 2}/ZnFe{sub 2}O{sub 4} exhibited an improved performance compared with TiO{sub 2}/ZnFe{sub 2}O{sub 4} or ZnFe{sub 2}O{sub 4} because of the formation of a heterostructure at the interface as well as the introduction of N species. Active species such as holes, electrons, hydroxyl radicals, and superoxide radicals involved in the photodegradation process were detected by using different types of scavengers. Because of ZnFe{sub 2}O{sub 4} in the hybrid, the catalyst shows ferromagnetism, and thus, the hybrid catalyst is easily isolated from the reaction mixture after the photocatalytic experiments. This work not only offers a simple method for the fabrication of N doped TiO{sub 2}/ZnFe{sub 2}O{sub 4} hybrids, but also provides an effective and conveniently recyclable photocatalyst for the

  18. BIOMOLECULES CONTAINED POLYETHYLENE TO DEGRADATION BY MICRO-ORGANISMS

    OpenAIRE

    Ashadeepika Lazras

    2017-01-01

    The mechanisms of degradation of polyethylene films are various ways such in soil containing microbes. The culture micro-organisms with suitable media such as SDA and YEMA contained some biochemical such as Starch, Cellulose and Plant Extract for both fungi and agro-bacteria.The biochemical substrate has increased the degradation efficiency. In this investigation highest degradation of polythene at 59.69% by micro-organisms in which contained MPE compared to other.

  19. 75 FR 55613 - General Motors Corporation, Renaissance Center, Including On-Site Leased Workers From Accretive...

    Science.gov (United States)

    2010-09-13

    ... Employment and Training Administration General Motors Corporation, Renaissance Center, Including On-Site... of General Motors Corporation, Renaissance Center, including on-site leased workers from Accretive... location of General Motors Corporation, Renaissance Center. The Department has determined that on-site...

  20. 77 FR 13351 - Polaris Industries, Including On-site Leased Workers From Westaff, Supply Technologies, Aerotek...

    Science.gov (United States)

    2012-03-06

    ... Employment and Training Administration Polaris Industries, Including On-site Leased Workers From Westaff..., applicable to workers of Polaris Industries, including on-site leased workers from Westaff, Osceola... were employed on-site at the Osceola, Wisconsin location of Polaris Industries. The Department has...

  1. 76 FR 4724 - Polaris Industries, Including On-Site Leased Workers From Westaff and Supply Technologies...

    Science.gov (United States)

    2011-01-26

    ... Employment and Training Administration Polaris Industries, Including On-Site Leased Workers From Westaff and... Assistance on August 26, 2010, applicable to workers of Polaris Industries, including on-site leased workers... employed on-site at the Osceola, Wisconsin location of Polaris Industries. The Department has determined...

  2. 75 FR 77666 - Polaris Industries, Including On-Site Leased Workers From Westaff and Supply Technologies...

    Science.gov (United States)

    2010-12-13

    ... Employment and Training Administration Polaris Industries, Including On-Site Leased Workers From Westaff and... Assistance on August 26, 2010, applicable to workers of Polaris Industries, including on-site leased workers... employed on-site at the Osceola, Wisconsin location of Polaris Industries. The Department has determined...

  3. ALTERNATIVE METHOD FOR ON SITE EVALUATION OF THERMAL TRANSMITTANCE

    Directory of Open Access Journals (Sweden)

    Aleksandar Janković

    2017-08-01

    Full Text Available Thermal transmittance or U-value is an indicator of the building envelope thermal properties and a key parameter for evaluation of heat losses through the building elements due to heat transmission. It can be determined by calculation based on thermal characteristics of the building element layers. However, this value does not take into account the effects of irregularities and degradation of certain elements of the envelope caused by aging, which may lead to errors in calculation of the heat losses. An effective and simple method for determination of thermal transmittance is in situ measurement, which is governed by the ISO 9869-1:2014 that defines heat flow meter method. This relatively expensive method leaves marks and damages surface of the building element. Furthermore, the final result is not always reliable, in particular when the building element is light or when the weather conditions are not suitable. In order to avoid the above mentioned problems and to estimate the real thermal transmittance value an alternative experimental method, here referred as the natural convection and radiation method, is proposed in this paper. For determination of thermal transmittance, this method requires only temperatures of inside and outside air, as well as the inner wall surface temperature. A detailed statistical analysis, performed by the software package SPSS ver. 20, shows several more advantages of this method comparing to the standard heat flow meter one, besides economic and non-destructive benefits.

  4. Intermittent degradation and schizotypy

    Directory of Open Access Journals (Sweden)

    Matthew W. Roché

    2015-06-01

    Full Text Available Intermittent degradation refers to transient detrimental disruptions in task performance. This phenomenon has been repeatedly observed in the performance data of patients with schizophrenia. Whether intermittent degradation is a feature of the liability for schizophrenia (i.e., schizotypy is an open question. Further, the specificity of intermittent degradation to schizotypy has yet to be investigated. To address these questions, 92 undergraduate participants completed a battery of self-report questionnaires assessing schizotypy and psychological state variables (e.g., anxiety, depression, and their reaction times were recorded as they did so. Intermittent degradation was defined as the number of times a subject’s reaction time for questionnaire items met or exceeded three standard deviations from his or her mean reaction time after controlling for each item’s information processing load. Intermittent degradation scores were correlated with questionnaire scores. Our results indicate that intermittent degradation is associated with total scores on measures of positive and disorganized schizotypy, but unrelated to total scores on measures of negative schizotypy and psychological state variables. Intermittent degradation is interpreted as potentially derivative of schizotypy and a candidate endophenotypic marker worthy of continued research.

  5. REPORT OF ON-SITE INSPECTION WORKSHOP-16

    Energy Technology Data Exchange (ETDEWEB)

    Sweeney, J J

    2009-07-07

    The central issue addressed by this workshop was the task of making the on-site inspection (OSI) part of the Comprehensive Nuclear-Test-Ban Treaty verification system operationally ready at entry into force of the Treaty. It is recognized, and this was emphasized by the 2008 OSI Integrated Field Exercise (IFE), that it is not possible to develop every part of the OSI regime simultaneously. Therefore, it is necessary to prioritize the approach to OSI readiness. The reviews of the IFE have pointed to many elements of OSI readiness that still need development. The objective of this workshop was to provide priorities for the path forward for Working Group B to consider. Several critical areas have been identified that are related to the development of OSI readiness: (1) Technology development: Priorities are radionuclide and noble gas sampling and analysis, visual observation, multispectral/infrared imaging methods, active seismic methods and the recognition of the importance of signatures. (2) Organizational development: Priorities are health and safety, the Operations Support Centre, the Equipment Storage and Maintenance Facility, information technology data flow and communications. (3) Resources: The expertise to develop key parts of the OSI regime is not available within the current OSI Division staff. To develop these aspects of the regime will require more staff or supplements to the staff with cost-free experts or other means. Aspects of the system that could benefit from more staff include radionuclide and noble gas detection methods, data flow and communications, visual observation, multispectral/infrared methods and health and safety. As the path forward, participants of this workshop recognized a need to optimize the development of OSI priorities. The outcome of this workshop is to suggest for consideration an operational approach to OSI readiness that utilizes results of an evaluation of the relative effectiveness of OSI elements versus their relative

  6. Global Scale Methane Emissions from On-Site Wastewater Management

    Science.gov (United States)

    Reid, M. C.; Guan, K.; Mauzerall, D. L.

    2013-12-01

    Pit latrines and other on-site sanitation methods are important forms of wastewater management at the global scale, providing hygienic and low-cost sanitation for more than 1.7 billion people in developing and middle-income regions. Latrines have also been identified as major sources of the greenhouse gas methane (CH4) from the anaerobic decomposition of organic waste in pits. Understanding the greenhouse gas footprint of different wastewater systems is essential for sustainable water resource development and management. Despite this importance, CH4 emissions from decentralized wastewater treatment have received little attention in the scientific literature, and the rough calculations underlying government inventories and integrated assessment models do not accurately capture variations in emissions within and between countries. In this study, we improve upon earlier efforts and develop the first spatially explicit approach to quantifying latrine CH4 emissions, combining a high-resolution geospatial analysis of population, urbanization, and water table (as an indicator of anaerobic decomposition pathways) with CH4 emissions factors from the 2006 IPCC Guidelines for National Greenhouse Gas Inventories. Country-level health and sanitation surveys were used to determine latrine utilization in 2000 and predict usage in 2015. 18 representative countries in Asia, Africa, and Latin America were selected for this analysis to illustrate regional variations in CH4 emissions and to include the greatest emitting nations. Our analysis confirms that pit latrines are a globally significant anthropogenic CH4 source, emitting 4.7 Tg CH4 yr-1 in the countries considered here. This total is projected to decrease ~25% by 2015, however, driven largely by rapid urbanization in China and decreased reliance on latrines in favor of flush toilets. India has the greatest potential for large growth in emissions in the post-2015 period, since public health campaigns to end open defecation

  7. Mapping the polysaccharide degradation potential of Aspergillus niger

    NARCIS (Netherlands)

    Andersen, M.R.; Giese, M.; De Vries, R.P.; Nielsen, J.

    2012-01-01

    Background The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required. For

  8. Optimization of chloroxylenol degradation by Aspergillus niger using ...

    African Journals Online (AJOL)

    Chloroxylenol is a very toxic phenolic derivative and it represents potential hazard towards human health and to the environment. Aspergillus niger, local isolate, is an efficient fungus to degrade 99.72% of 2 mg/L of chloroxylenol after 7 days of fermentation. It also has a high capacity to degrade 91.83% of higher ...

  9. Biodegradation and growth characteristics of a toluene-degrading ...

    African Journals Online (AJOL)

    A toluene-degrading strain was isolated from active sludge in this study. Both growth characteristic and the performance to degrade toluene by the strain in batch culture mode were evaluated. Results showed that the isolated strain presented a good ability to remove toluene with the maximum removal efficiency of 93.8%.

  10. Nitrogen and carbon dynamics beneath on-site wastewater treatment systems in Pitt County, North Carolina.

    Science.gov (United States)

    Del Rosario, Katie L; Humphrey, Charles P; Mitra, Siddhartha; O'Driscoll, Michael A

    2014-01-01

    On-site wastewater treatment systems (OWS) are a potentially significant non-point source of nutrients to groundwater and surface waters, and are extensively used in coastal North Carolina. The goal of this study was to determine the treatment efficiency of four OWS in reducing total dissolved nitrogen (TDN) and dissolved organic carbon (DOC) concentrations before discharge to groundwater and/or adjacent surface water. Piezometers were installed for groundwater sample collection and nutrient analysis at four separate residences that use OWS. Septic tank effluent, groundwater, and surface water samples (from an adjacent stream) were collected four times during 2012 for TDN and DOC analysis and pH, temperature, electrical conductivity, and dissolved oxygen measurements. Treatment efficiencies from the tank to the groundwater beneath the drainfields ranged from 33 to 95% for TDN and 45 to 82% for DOC, although dilution accounted for most of the concentration reductions. There was a significant positive correlation between nitrate concentration and separation distance from trench bottom to water table and a significant negative correlation between DOC concentration and separation distance. The TDN and DOC transport (>15 m) from two OWS with groundwater saturated drainfield trenches was significant.

  11. Degradation of textile dyes by cyanobacteria

    Directory of Open Access Journals (Sweden)

    Priscila Maria Dellamatrice

    Full Text Available Abstract Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black, and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds.

  12. Degradation of textile dyes by cyanobacteria.

    Science.gov (United States)

    Dellamatrice, Priscila Maria; Silva-Stenico, Maria Estela; Moraes, Luiz Alberto Beraldo de; Fiore, Marli Fátima; Monteiro, Regina Teresa Rosim

    Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  13. Degradation of implant materials

    CERN Document Server

    Eliaz, Noam

    2012-01-01

    This book surveys the degradation of implant materials, reviewing in detail such failure mechanisms as corrosion, fatigue and wear, along with monitoring techniques. Surveys common implant biomaterials, as well as procedures for implant retrieval and analysis.

  14. Thraustochytrid protists degrade hydrocarbons

    Digital Repository Service at National Institute of Oceanography (India)

    Raikar, M.T.; Raghukumar, S.; Vani, V.; David, J.J.; Chandramohan, D.

    that thraustochytrids have the capability to utilize a wide range of organic nitrogen and carbon compounds for their nutrition. However, the capability of these protists to degrade hydrocarbons has not been examined so far. Hydrocarbons occur in seawater either... chromatography. (1) Gravimetry: Tarballs were extracted from experimental flasks with 10 ml of carbon tetrachloride, the extract transferred to pre- weighed Petri dish and the solvent allowed to RAIKAR et al.: THRAUSTOCHYTRID PROTISTS DEGRADE HYDROCARBONS...

  15. Degradation of cellulose by basidiomycetous fungi.

    Science.gov (United States)

    Baldrian, Petr; Valásková, Vendula

    2008-05-01

    Cellulose is the main polymeric component of the plant cell wall, the most abundant polysaccharide on Earth, and an important renewable resource. Basidiomycetous fungi belong to its most potent degraders because many species grow on dead wood or litter, in environment rich in cellulose. Fungal cellulolytic systems differ from the complex cellulolytic systems of bacteria. For the degradation of cellulose, basidiomycetes utilize a set of hydrolytic enzymes typically composed of endoglucanase, cellobiohydrolase and beta-glucosidase. In some species, the absence of cellobiohydrolase is substituted by the production of processive endoglucanases combining the properties of both of these enzymes. In addition, systems producing hydroxyl radicals based on cellobiose dehydrogenase, quinone redox cycling or glycopeptide-based Fenton reaction are involved in the degradation of several plant cell wall components, including cellulose. The complete cellulolytic complex used by a single fungal species is typically composed of more than one of the above mechanisms that contribute to the utilization of cellulose as a source of carbon or energy or degrade it to ensure fast substrate colonization. The efficiency and regulation of cellulose degradation differs among wood-rotting, litter-decomposing, mycorrhizal or plant pathogenic fungi and yeasts due to the different roles of cellulose degradation in the physiology and ecology of the individual groups.

  16. Industrial paramedics, out on site but not out of mind.

    Science.gov (United States)

    Acker, Joseph J; Johnston, Tania M; Lazarsfeld-Jensen, Ann

    2014-01-01

    (MOEMS). There is no single definition or comprehensive role description for industrial paramedic practice within the literature. Worldwide, there is little high-quality published evidence to adequately reflect all aspects of industrial paramedic practice. However, based on the literature available, this definition is offered: 'An industrial paramedic is an advanced clinical practitioner in paramedicine with an expanded scope of practice. The industrial paramedic provides emergency response, primary health care, chronic disease management, injury prevention, health promotion, medical referral, and repatriation coordination at remote mining sites, offshore installations, and other isolated industry settings. The industrial paramedic is resourceful, adaptable, and comfortable working independently. Industrial paramedics practice on site with limited resources, remotely located from tertiary care, and use telemedicine to consult with other health professionals as required. Industrial paramedics are experts at rapidly assessing, prioritising, and establishing control in their unpredictable workspace to reduce risks and create an environment conducive to quality patient care. The industrial paramedic preferably holds a specialised tertiary qualification and is committed to maintaining their clinical competency through continuing professional development.' Further research is required to validate, refute, or expand this proposed definition.

  17. DDE remediation and degradation.

    Science.gov (United States)

    Thomas, John E; Ou, Li-Tse; All-Agely, Abid

    2008-01-01

    DDT and its metabolites, DDD and DDE, have been shown to be recalcitrant to degradation. The parent compound, DDT, was used extensively worldwide starting in 1939 and was banned in the United States in 1973. The daughter compound, DDE, may result from aerobic degradation, abiotic dehydrochlorination, or photochemical decomposition. DDE has also occurred as a contaminant in commercial-grade DDT. The p,p'-DDE isomer is more biologically active than the o,p-DDE, with a reported half-life of -5.7 years. However, when DDT was repeatedly applied to the soil, the DDE concentration may remain unchanged for more than 20 yr. Remediation of DDE-contaminated soil and water may be done by several techniques. Phytoremediation involves translocating DDT, DDD, and DDE from the soil into the plant, although some aquatic species (duckweed > elodea > parrot feather) can transform DDT into predominantly DDD with some DDE being formed. Of all the plants that can uptake DDE, Cucurbita pepo has been the most extensively studied, with translocation values approaching "hyperaccumulation" levels. Soil moisture, temperature, and plant density have all been documented as important factors in the uptake of DDE by Cucurbita pepo. Uptake may also be influenced positively by amendments such as biosurfactants, mycorrhizal inoculants, and low molecular weight organic acids (e.g., citric and oxalic acids). DDE microbial degradation by dehalogenases, dioxygenases, and hydrolases occurs under the proper conditions. Although several aerobic degradation pathways have been proposed, none has been fully verified. Very few aerobic pure cultures are capable of fully degrading DDE to CO2. Cometabolism of DDE by Pseudomonas sp., Alicaligens sp., and Terrabacter sp. grown on biphenyl has been reported; however, not all bacterial species that produce biphenyl dioxygenase degraded DDE. Arsenic and copper inhibit DDE degradation by aerobic microorganisms. Similarly, metal chelates such as EDTA inhibit the

  18. Understanding Degradation Pathways in Organic Photovoltaics (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, M. T.; Olson, D. C.; Garcia, A.; Kauvar, I.; Kopidakis, N.; Reese, M. O.; Berry, J. J.; Ginley, D. S.

    2011-02-01

    Organic Photovoltaics (OPVs) recently attained power conversion efficiencies that are of interest for commercial production. Consequently, one of the most important unsolved issues facing a new industry is understanding what governs lifetime in organic devices and discovering solutions to mitigate degradation mechanisms. Historically, the active organic components are considered vulnerable to photo-oxidation and represent the primary degradation channel. However, we present several (shelf life and light soaking) studies pointing the relative stability of the active layers and instabilities in commonly used electrode materials. We show that engineering of the hole/electron layer at the electrode can lead to environmentally stable devices even without encapsulation.

  19. Degradation of TATP, TNT, and RDX using mechanically alloyed metals

    Science.gov (United States)

    Clausen, Christian (Inventor); Geiger, Cherie (Inventor); Sigman, Michael (Inventor); Fidler, Rebecca (Inventor)

    2012-01-01

    Bimetallic alloys prepared in a ball milling process, such as iron nickel (FeNi), iron palladium (FePd), and magnesium palladium (MgPd) provide in situ catalyst system for remediating and degrading nitro explosive compounds. Specifically, munitions, such as, 2,4,6-trinitrotoluene (TNT), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX), nitrocellulose and nitroglycerine that have become contaminants in groundwater, soil, and other structures are treated on site to remediate explosive contamination.

  20. On-site co-generation: cost savings in view

    Energy Technology Data Exchange (ETDEWEB)

    Granson, E.

    2004-03-31

    The technical and economic aspects of cogeneration are explained with examples from Alberta and British Columbia. One of the examples is the cogeneration of steam and electricity at the ATCO/EPCOR/NOVA power plant in Joffre, Alberta, which generates enough electricity, steam and heat to supply the whole ethylene and polyethylene plant; it also boosts the provincial grid by four per cent. Another good example cited is TransCanada Pipelines' Carseland, Alberta, operation, which generates 80 MW of electricity, along with about 120 tonnes/hr of steam for Agrium's adjacent Carseland Nitrogen Operation. The electricity is generated by two GE LM6000 PD combustion turbines using natural gas as fuel. Each turbine is equipped with a Heat Recovery Steam Generator (HRSG), which captures the gas turbine exhaust heat to raise steam. The high pressure, superheated steam is sent to the Agrium facility for use by the company's nitrogen operation. Dow Chemical Canada Inc also has a power and utilities combined-cycle cogeneration plant at its Fort Saskatchewan site. By utilizing a steam turbine down the line, Dow Chemicals' Fort Saskatchewan operations are able to achieve at least an 80 per cent thermal efficiency rating for the overall process, or about a 10 to 20 per cent gain on alternate designs. The Dow Canada plant operates three GE gas turbines and two steam turbines for a total rated capacity of 300 MW of power. Cogeneration is not limited to turbines fuelled by natural gas; pulp and paper mills throughout Western Canada use wood residue as fuel to produce steam and the hot water required by the mills. Methane gas is another source of fuel being put to use in the Vancouver Landfill Cogeneration Facility at Delta, BC, which, using three Caterpillar 3532 engines, generates 5.6 MW of electricity and 6.7 MW of thermal energy. The electricity is sold to BC Hydro, while the thermal energy is used by the CanAgro greenhouses. In addition to the substantial

  1. Agile sustainable communities. On-site renewable energy generation

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Woodrow W. II. [A. Gary Anderson Graduate School of Management, University of California, Riverside (United States); Eisenberg, Larry [Los Angeles Community College District (United States)

    2008-12-15

    Smart and sustainable campuses demand three components. First, there is the need to have a Strategic Master Plan (SMP) for all infrastructures that include energy, transportation, water, waste and telecommunications along with the traditional dimensions of research, curricula, outreach and assessments. Secondarily, there is the array of issues pertaining to the sitting of buildings and overall facility master planning which must be addressed from the perspective of 'green' energy, efficient orientation and be designed for multiple-use by the academic and local community. Thirdly, the development of sustainable buildings in one area that is compact and walkable campuses thus enable a range of transportation choices leads to reduced energy consumption. Historically, college campuses were often like towns and villages in that they are self-sustaining for family, business and recreational activities. Any sustainable smart campus is a vibrant, 'experiential' applied educational model that should catalyze creative learning. More significantly, today, campuses and communities must be secure in terms of not only their own energy use and needs, but also for the resource demands of their power. Otherwise, the community(s) will never be secure economically or politically. Recognizing global warming and climate change, in the spring of 2001, the Board of Trustee (BOT) for the Los Angeles Community College District (LACCD) took the critical initial policy steps to turn these sustainable developments into goals. For example, the LACCD decided to have new 'green' buildings to replace or renovate existing ones. The building program led to sustainable communities that included recycling, product reuse from waste as well as smart growth in terms of reduced energy use, efficiency and the use of telecommunication and wireless systems. The paper focuses primarily on the energy programs for the LACCD campuses. The paper considers the overall energy

  2. Drift Degradation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    D. Kicker

    2004-09-16

    Degradation of underground openings as a function of time is a natural and expected occurrence for any subsurface excavation. Over time, changes occur to both the stress condition and the strength of the rock mass due to several interacting factors. Once the factors contributing to degradation are characterized, the effects of drift degradation can typically be mitigated through appropriate design and maintenance of the ground support system. However, for the emplacement drifts of the geologic repository at Yucca Mountain, it is necessary to characterize drift degradation over a 10,000-year period, which is well beyond the functional period of the ground support system. This document provides an analysis of the amount of drift degradation anticipated in repository emplacement drifts for discrete events and time increments extending throughout the 10,000-year regulatory period for postclosure performance. This revision of the drift degradation analysis was developed to support the license application and fulfill specific agreement items between the U.S. Nuclear Regulatory Commission (NRC) and the U.S. Department of Energy (DOE). The earlier versions of ''Drift Degradation Analysis'' (BSC 2001 [DIRS 156304]) relied primarily on the DRKBA numerical code, which provides for a probabilistic key-block assessment based on realistic fracture patterns determined from field mapping in the Exploratory Studies Facility (ESF) at Yucca Mountain. A key block is defined as a critical block in the surrounding rock mass of an excavation, which is removable and oriented in an unsafe manner such that it is likely to move into an opening unless support is provided. However, the use of the DRKBA code to determine potential rockfall data at the repository horizon during the postclosure period has several limitations: (1) The DRKBA code cannot explicitly apply dynamic loads due to seismic ground motion. (2) The DRKBA code cannot explicitly apply loads due to thermal

  3. Performance of airlift MBR for on-site treatment of slaughterhouse wastewater in urban areas of Vietnam.

    Science.gov (United States)

    Do, Anh Tien; Bach, Dung Quang; Do, Uan Khac; Prieto, Ana; Lan Huong, Huynh Thi

    2016-11-01

    In many cities in Vietnam, wastewater generated in slaughterhouses is normally discharged directly into surface waters without treatment. Management of slaughterhouse wastewater (SHWW) is difficult due to the lack of infrastructure for conveyance to centralized facilities. On-site treatment presents one cost-effective way of managing SHWW compared to mass improvement of infrastructure. This study evaluates the application of an airlift membrane bioreactor (AL-MBR) for on-site treatment of SHWW. The concentrations of chemical oxygen demand (COD), biochemical oxygen demand (BOD), total nitrogen (TN) and NH4(+)-N in the simulated SHWW were 1,697 ± 317 mg/L, 891 ± 137 mg/L, 246 ± 65 mg/L and 171 ± 4.2 mg/L, respectively. The mixed-liquor volatile suspended solids in the aerobic and anoxic tanks were maintained at 5,000-6,000 mg/L. Air flow rate and cross flow velocity were maintained at 0.2 L/min and 0.8 m/s, respectively, to keep the trans-membrane pressure (TMP) stable at 0.8 bar and the membrane flux at 15-18 L/m(2) h bar (LMH/bar). The removal efficiencies of COD and TN were 95 ± 1.9% and 70 ± 3.3%, respectively, at a hydraulic retention time (HRT) of 2.5 days. This study shows that GL-MBR is a promising on-site solution for SHWW treatment.

  4. On-site and in situ remediation technologies applicable to petroleum hydrocarbon contaminated sites in the Antarctic and Arctic

    Directory of Open Access Journals (Sweden)

    Danielle Camenzuli

    2015-09-01

    Full Text Available Petroleum hydrocarbon contaminated sites, associated with the contemporary and legacy effects of human activities, remain a serious environmental problem in the Antarctic and Arctic. The management of contaminated sites in these regions is often confounded by the logistical, environmental, legislative and financial challenges associated with operating in polar environments. In response to the need for efficient and safe methods for managing contaminated sites, several technologies have been adapted for on-site or in situ application in these regions. This article reviews six technologies which are currently being adapted or developed for the remediation of petroleum hydrocarbon contaminated sites in the Antarctic and Arctic. Bioremediation, landfarming, biopiles, phytoremediation, electrokinetic remediation and permeable reactive barriers are reviewed and discussed with respect to their advantages, limitations and potential for the long-term management of soil and groundwater contaminated with petroleum hydrocarbons in the Antarctic and Arctic. Although these technologies demonstrate potential for application in the Antarctic and Arctic, their effectiveness is dependent on site-specific factors including terrain, soil moisture and temperature, freeze–thaw processes and the indigenous microbial population. The importance of detailed site assessment prior to on-site or in situ implementation is emphasized, and it is argued that coupling of technologies represents one strategy for effective, long-term management of petroleum hydrocarbon contaminated sites in the Antarctic and Arctic.

  5. Demonstration of an on-site PAFC cogeneration system with waste heat utilization by a new gas absorption chiller

    Energy Technology Data Exchange (ETDEWEB)

    Urata, Tatsuo [Tokyo Gas Company, LTD, Tokyo (Japan)

    1996-12-31

    Analysis and cost reduction of fuel cells is being promoted to achieve commercial on-site phosphoric acid fuel cells (on-site FC). However, for such cells to be effectively utilized, a cogeneration system designed to use the heat generated must be developed at low cost. Room heating and hot-water supply are the most simple and efficient uses of the waste heat of fuel cells. However, due to the short room-heating period of about 4 months in most areas in Japan, the sites having demand for waste heat of fuel cells throughout the year will be limited to hotels and hospitals Tokyo Gas has therefore been developing an on-site FC and the technology to utilize tile waste heat of fuel cells for room cooling by means of an absorption refrigerator. The paper describes the results of fuel cell cogeneration tests conducted on a double effect gas absorption chiller heater with auxiliary waste heat recovery (WGAR) that Tokyo Gas developed in its Energy Technology Research Laboratory.

  6. Degradation of toluene-2,4-diamine by persulphate: kinetics, intermediates and degradation pathway.

    Science.gov (United States)

    Jiang, Yong-hai; Zhang, Jin-bao; Xi, Bei-dou; An, Da; Yang, Yu; Li, Ming-xiao

    2015-01-01

    In this study, the degradation of toluene-2,4-diamine (TDA) by persulphate (PS) in an aqueous solution at near-neutral pH was examined. The result showed that the degradation rate of TDA increased with increasing PS concentrations. The optimal dosage of PS in the reaction system was determined by efficiency indicator (I) coupling in the consumption of PS and decay half-life of TDA. Calculation showed that 0.74 mM of PS was the most effective dosage for TDA degradation, at that level the maximum I of 24.51 was obtained. PS can oxidize TDA for an extended reaction time period. Under neutral condition without activation, four degradation intermediates, 2,4-diamino-3-hydroxy-5-sulfonicacidtoluene, 2,4-diaminobenzaldehyde, 2,4-bis(vinylamino)benzaldehyde and 3,5-diamino-4-hydroxy-2-pentene, were identified by high-performance liquid chromatography-mass spectrometry. The tentative degradation pathway of TDA was proposed as well. It was found that hydroxyl radical played an important role in degradation of TDA with the activation of Fe2+, whereas PS anion and sulphate radicals were responsible for the degradation without activation of Fe2+.

  7. Economies of density for on-site waste water treatment.

    Science.gov (United States)

    Eggimann, Sven; Truffer, Bernhard; Maurer, Max

    2016-09-15

    Decentralised wastewater treatment is increasingly gaining interest as a means of responding to sustainability challenges. Cost comparisons are a crucial element of any sustainability assessment. While the cost characteristics of centralised waste water management systems (WMS) have been studied extensively, the economics of decentralised WMS are less understood. A key motivation for studying the costs of decentralised WMS is to compare the cost of centralised and decentralised WMS in order to decide on cost-efficient sanitation solutions. This paper outlines a model designed to assess those costs which depend on the spatial density of decentralised wastewater treatment plants in a region. Density-related costs are mostly linked to operation and maintenance activities which depend on transportation, like sludge removal or the visits of professionals to the plants for control, servicing or repairs. We first specify a modelled cost-density relationship for a region in a geometric two-dimensional space by means of heuristic routing algorithms that consider time and load-capacity restrictions. The generic model is then applied to a Swiss case study for which we specify a broad range of modelling parameters. As a result, we identify a 'hockey-stick'-shaped cost curve that is characterised by strong cost reductions at high density values which level out at around 1 to 1.5 plants per km(2). Variations in the cost curves are mostly due to differences in management approaches (scheduled or unscheduled emptying). In addition to the well-known diseconomies of scale in the case of centralised sanitation, we find a similar generic cost behaviour for decentralised sanitation due to economies of density. Low densities in sparsely populated regions thus result in higher costs for both centralised and decentralised system. Policy implications are that efforts to introduce decentralised options in a region should consider the low-density/high-cost problem when comparing centralised

  8. Purification of highly chlorinated dioxins degrading enzyme

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, K.; Furuichi, T.; Koike, K.; Kuboshima, M. [Hokkaido Univ. (Japan). Division of Environment Resource Engineering, Graduate School of Engineering

    2004-09-15

    Soil contamination caused by dioxins in and around sites of incinerators for municipal solid waste (MSW) is a concern in Japan. For example, scattering wastewater from a wet gas scrubber at an MSW incinerator facility in Nose, Osaka caused soil and surface water contamination. The concentration of dioxins in the soil was about 8,000 pg-TEQ/g. Other contamination sites include soils on which fly ash has been placed directly or improperly stored and landfill sites that have received bottom and fly ash over a long period. Some countermeasures are required immediately at these dioxins-contaminated sites. We have previously developed bioreactor systems for dioxin-contaminated water and soil. We have shown that a fungus, Pseudallescheria boydii (P. boydii), isolated from activated sludge treating wastewater that contained dioxins, has the ability to degrade highly chlorinated dioxins. A reaction product of octachlorinated dibenzo-p-dioxin (OCDD) was identified as heptachlorinated dibenzo-p-dioxin. Therefore, one of the pathways for degradation of OCDD by this fungus was predicted to be as follows: OCDD is transformed by dechlorination and then one of the remaining aromatic rings is oxidized. To apply P. boydii to on-site technologies (e.g., bioreactor systems), as well as in situ technologies, enzyme treatment using a dioxin-degrading enzyme from P. boydii needs to be developed because P. boydii is a weak pathogenic fungus, known to cause opportunistic infection. As a result, we have studied enzyme purification of nonchlorinated dioxin, namely, dibenzo-pdioxin (DD). However, we did not try to identify enzymes capable of degrading highly chlorinated dioxins. This study has elucidated a method of enzyme assay for measuring OCDD-degrading activity, and has attempted to purify OCDD-degrading enzymes from P. boydii using enzyme assay. In addition, as first step toward purifying 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD), 2,3,7,8-TCDD degradation tests were carried out

  9. Degradation of Silicone Encapsulants in CPV Optics

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Can; Miller, David C.; Tappan, Ian A.; Dauskardt, Reinhold H.

    2016-11-21

    High efficiency multijunction solar cells in terrestrial concentrator photovoltaic (CPV) modules are becoming an increasingly cost effective and viable option in utility scale power generation. As with other utility scale photovoltaics, CPV modules need to guarantee operational lifetimes of at least 25 years. The reliability of optical elements in CPV modules poses a unique materials challenge due to the increased UV irradiance and enhanced temperature cycling associated with concentrated solar flux. The polymeric and thin film materials used in the optical elements are especially susceptible to UV damage, diurnal temperature cycling and active chemical species from the environment. We used fracture mechanics approaches to study the degradation modes including: the adhesion between the encapsulant and the cell or secondary optical element; and the cohesion of the encapsulant itself. Understanding the underlying mechanisms of materials degradation under elevated stress conditions is critical for commercialization of CPV technology and can offer unique insights into degradation modes in similar encapsulants used in other photovoltaic modules.

  10. Motor degradation prediction methods

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, J.R.; Kelly, J.F.; Delzingaro, M.J.

    1996-12-01

    Motor Operated Valve (MOV) squirrel cage AC motor rotors are susceptible to degradation under certain conditions. Premature failure can result due to high humidity/temperature environments, high running load conditions, extended periods at locked rotor conditions (i.e. > 15 seconds) or exceeding the motor`s duty cycle by frequent starts or multiple valve stroking. Exposure to high heat and moisture due to packing leaks, pressure seal ring leakage or other causes can significantly accelerate the degradation. ComEd and Liberty Technologies have worked together to provide and validate a non-intrusive method using motor power diagnostics to evaluate MOV rotor condition and predict failure. These techniques have provided a quick, low radiation dose method to evaluate inaccessible motors, identify degradation and allow scheduled replacement of motors prior to catastrophic failures.

  11. CELLULOSE DEGRADATION BY OXIDATIVE ENZYMES

    Directory of Open Access Journals (Sweden)

    Maria Dimarogona

    2012-09-01

    Full Text Available Enzymatic degradation of plant biomass has attracted intensive research interest for the production of economically viable biofuels. Here we present an overview of the recent findings on biocatalysts implicated in the oxidative cleavage of cellulose, including polysaccharide monooxygenases (PMOs or LPMOs which stands for lytic PMOs, cellobiose dehydrogenases (CDHs and members of carbohydrate-binding module family 33 (CBM33. PMOs, a novel class of enzymes previously termed GH61s, boost the efficiency of common cellulases resulting in increased hydrolysis yields while lowering the protein loading needed. They act on the crystalline part of cellulose by generating oxidized and non-oxidized chain ends. An external electron donor is required for boosting the activity of PMOs. We discuss recent findings concerning their mechanism of action and identify issues and questions to be addressed in the future.

  12. Cellulose degradation by oxidative enzymes

    Directory of Open Access Journals (Sweden)

    Maria Dimarogona

    2012-09-01

    Full Text Available Enzymatic degradation of plant biomass has attracted intensive research interest for the production of economically viable biofuels. Here we present an overview of the recent findings on biocatalysts implicated in the oxidative cleavage of cellulose, including polysaccharide monooxygenases (PMOs or LPMOs which stands for lytic PMOs, cellobiose dehydrogenases (CDHs and members of carbohydrate-binding module family 33 (CBM33. PMOs, a novel class of enzymes previously termed GH61s, boost the efficiency of common cellulases resulting in increased hydrolysis yields while lowering the protein loading needed. They act on the crystalline part of cellulose by generating oxidized and non-oxidized chain ends. An external electron donor is required for boosting the activity of PMOs. We discuss recent findings concerning their mechanism of action and identify issues and questions to be addressed in the future.

  13. Effect of Various Additives on Photocatalytic Degradation of 4-Nitrophenol

    Directory of Open Access Journals (Sweden)

    Kashif Naeem

    2009-01-01

    Full Text Available The photocatalytic degradation of 4-nitrophenol (4-NP assisted by titanium dioxide (TiO2 was investigated in aqueous suspension under irradiation by UV light. The effect of different supporting materials mixed physically with TiO2on the photocatalytic degradation of 4-NP has been studied. TiO2 with all supports exhibits good degradation efficiency of 4-NP and was better than TiO2 alone. The addition of SiO2 and ZSM-5 only caused a little change in 4-NP degradation. However, degradation of 4-NP was improved from 34.89% to 60.53% within 120 min photocatalysis in the presence of optimal amount of AC. The degradation was also fairly enhanced in the presence of cheaper rice husk and the activity was closed to AC.

  14. Characterization and Degradation of Pectic Polysaccharides in Cocoa Pulp.

    Science.gov (United States)

    Meersman, Esther; Struyf, Nore; Kyomugasho, Clare; Jamsazzadeh Kermani, Zahra; Santiago, Jihan Santanina; Baert, Eline; Hemdane, Sami; Vrancken, Gino; Verstrepen, Kevin J; Courtin, Christophe M; Hendrickx, Marc; Steensels, Jan

    2017-11-08

    Microbial fermentation of the viscous pulp surrounding cocoa beans is a crucial step in chocolate production. During this process, the pulp is degraded, after which the beans are dried and shipped to factories for further processing. Despite its central role in chocolate production, pulp degradation, which is assumed to be a result of pectin breakdown, has not been thoroughly investigated. Therefore, this study provides a comprehensive physicochemical analysis of cocoa pulp, focusing on pectic polysaccharides, and the factors influencing its degradation. Detailed analysis reveals that pectin in cocoa pulp largely consists of weakly bound substances, and that both temperature and enzyme activity play a role in its degradation. Furthermore, this study shows that pulp degradation by an indigenous yeast fully relies on the presence of a single gene (PGU1), encoding for an endopolygalacturonase. Apart from their basic scientific value, these new insights could propel the selection of microbial starter cultures for more efficient pulp degradation.

  15. Synergistic degradation of chitosan by impinging stream and jet cavitation.

    Science.gov (United States)

    Huang, Yongchun; Wang, Pengfei; Yuan, Yuan; Ren, Xian'e; Yang, Feng

    2015-11-01

    Chitosan degradation was investigated using a combination of jet cavitation and impinging stream. Different operating parameters such as the initial concentration (1-5 g L(-1)), initial pH (3.2-4.8), solution temperature (30, 40, 50, 60, and 70°C), inlet pressure (0.1-0.45 MPa), and treatment time (0-120 min) were optimized to achieve the maximum degradation of chitosan. After the optimization of jet cavitation parameters, chitosan degradation was carried out using venturi tubes of different structures (the fluidic generator). The efficiency of the jet cavitation degradation was improved significantly by combining with impinging stream. The structures of the degradation products were characterized by Fourier-transform infrared spectroscopy and X-ray diffraction. This study has conclusively established that a combination of jet cavitation and impinging stream can be effectively used for the complete degradation of chitosan. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Antifoam degradation testing

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, D. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River Ecology Lab. (SREL); Zamecnik, J. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River Ecology Lab. (SREL); Newell, D. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River Ecology Lab. (SREL); Williams, M. S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River Ecology Lab. (SREL)

    2015-08-20

    This report describes the results of testing to quantify the degradation products resulting from the dilution and storage of Antifoam 747. Antifoam degradation is of concern to the Defense Waste Processing Facility (DWPF) due to flammable decomposition products in the vapor phase of the Chemical Process Cell vessels, as well as the collection of flammable and organic species in the offgas condensate. The discovery that hexamethyldisiloxane is formed from the antifoam decomposition was the basis for a Potential Inadequacy in the Safety Analysis declaration by the DWPF.

  17. On-site investigations of hydrocarbon contaminated soil by the Pollut-Eval methodology

    Energy Technology Data Exchange (ETDEWEB)

    Benoit, Y.; Prigent, S.; Haeseler, F

    2005-07-01

    characterisation. By the lack of sample pre-treatment and the adaptation of a cooled auto-sampler, short time analysis suited for light petroleum pollutant such as gasoline and kerosene. The simple protocol applied to the soil appeared rapidly suitable for keeping the track of depollution process efficiency. During its qualification, the analyser has been involved in rehabilitation process evaluation by analysing various contaminated soils before and after clean-up treatment. From 1999, IFP was frequently asked for on-site diagnosis involving Pollut-Eval methodology. So, IFP installed this lab equipment in a mobile van in order to qualify the methodology through real time and on-site diagnosis. In addition to the qualification program, the aim of the project was also to identify the analytical parameters available in the method and sufficient for field contaminated soil characterisation. During 2 years, all over France, IFP, Gester and Vinci Technologies gathered their effort to ensure 10-site diagnosis. The variety of pollutants encountered has enriched a data base that has been included in a user guide. The gathered experience ended by the design of a compact apparatus dedicated to field analyses. Its small size and weight (less than 20 kg) was designed to perform on-site and autonomous characterisations. (authors)

  18. Stormwater management criteria for on-site pollution control: a comparative assessment of international practices.

    Science.gov (United States)

    Sage, Jérémie; Berthier, Emmanuel; Gromaire, Marie-Christine

    2015-07-01

    Over the last decade, a growing interest has been shown toward innovative stormwater management practices, breaking away from conventional "end of pipe" approaches (based on conveying water offsite to centralized detention facilities). Innovative strategies, referred to as sustainable urban drainage systems, low impact development (LID) or green infrastructures, advocating for management of runoff as close to its origin as possible, have therefore gained a lot of popularity among practitioners and public authorities. However, while the need for pollution control is generally well accepted, there is no wide agreement about management criteria to be given to developers. This article hence aims to compare these criteria through literature analysis of different state or local stormwater management manuals or guidelines, investigating both their suitability for pollution control and their influence on best management practices selection and design. Four categories of criteria were identified: flow-rate limitations, "water quality volumes" (to be treated), volume reduction (through infiltration or evapotranspiration), and non-hydrologic criteria (such as loads reduction targets or maximum effluent concentrations). This study suggests that hydrologic criteria based on volume reduction (rather than treatment) might generally be preferable for on-site control of diffuse stormwater pollution. Nonetheless, determination of an appropriate management approach for a specific site is generally not straightforward and presents a variety of challenges for site designers seeking to satisfy local requirements in addressing stormwater quantity and quality issues. The adoption of efficient LID solution may therefore strongly depend on the guidance given to practitioners to account for these management criteria.

  19. The UASB reactor as an alternative for the septic tank for on-site sewage treatment.

    Science.gov (United States)

    Coelho, A L S S; do Nascimento, M B H; Cavalcanti, P F F; van Haandel, A C

    2003-01-01

    Although septic tanks are amply used for on site sewage treatment, these units have serious drawbacks: the removal efficiency of organic material and suspended solids is low, the units are costly and occupy a large area and operational cost is high due to the need for periodic desludging. In this paper an innovative variant of the UASB reactor is proposed as an alternative for the septic tank. This alternative has several important advantages in comparison with the conventional septic tank: (1) Although the volume of the UASB reactor was about 4 times smaller than the septic tank, its effluent quality was superior, even though small sludge particles were present, (2) desludging of the UASB reactor is unnecessary and even counterproductive, as the sludge mass guarantees proper performance, (3) the UASB reactor is easily transportable (compact and light) and therefore can be produced in series, strongly reducing construction costs and (4) since the concentration of colloids in the UASB effluent is much smaller than in the ST effluent, it is expected that the infiltration of the effluent will be much less problematic.

  20. Connecting Indicators with land degradation and desertification

    Science.gov (United States)

    Kosmas, C.

    2012-04-01

    to consider in this effort. Efficiency and performance indicators seem the most promising for further research, particularly combined with economic principles for assessing land degradation and desertification. Key words: Indicators, land degradation, desertification

  1. Detecting and monitoring deforestation and forest degradation: Issues and obstacles for Southeast Asia

    Science.gov (United States)

    Douglas Muchoney; Sharon Hamann

    2013-01-01

    Forest degradation can be defined as the loss of forest volume, biomass and/or forest productivity caused by natural or human influences. Achieving Reduced Emissions from Deforestation and Forest Degradation (REDD+) requires that deforestation and degradation can be efficiently, reliably, and cost-effectively detected and quantified, often where ground and aerial...

  2. Endocytic collagen degradation

    DEFF Research Database (Denmark)

    Madsen, Daniel H.; Jürgensen, Henrik J.; Ingvarsen, Signe Ziir

    2012-01-01

    it crucially important to understand both the collagen synthesis and turnover mechanisms in this condition. Here we show that the endocytic collagen receptor, uPARAP/Endo180, is a major determinant in governing the balance between collagen deposition and degradation. Cirrhotic human livers displayed a marked...

  3. Degradation of fluorotelomer alcohols

    DEFF Research Database (Denmark)

    Ellis, David A; Martin, Jonathan W; De Silva, Amila O

    2004-01-01

    . The significance of the gas-phase peroxy radical cross reactions that produce PFCAs has not been recognized previously. Such reactions are expected to occur during the atmospheric degradation of all polyfluorinated materials, necessitating a reexamination of the environmental fate and impact of this important...... class of industrial chemicals....

  4. Detection of pump degradation

    Energy Technology Data Exchange (ETDEWEB)

    Greene, R.H.; Casada, D.A.; Ayers, C.W. [and others

    1995-08-01

    This Phase II Nuclear Plant Aging Research study examines the methods of detecting pump degradation that are currently employed in domestic and overseas nuclear facilities. This report evaluates the criteria mandated by required pump testing at U.S. nuclear power plants and compares them to those features characteristic of state-of-the-art diagnostic programs and practices currently implemented by other major industries. Since the working condition of the pump driver is crucial to pump operability, a brief review of new applications of motor diagnostics is provided that highlights recent developments in this technology. The routine collection and analysis of spectral data is superior to all other technologies in its ability to accurately detect numerous types and causes of pump degradation. Existing ASME Code testing criteria do not require the evaluation of pump vibration spectra but instead overall vibration amplitude. The mechanical information discernible from vibration amplitude analysis is limited, and several cases of pump failure were not detected in their early stages by vibration monitoring. Since spectral analysis can provide a wealth of pertinent information concerning the mechanical condition of rotating machinery, its incorporation into ASME testing criteria could merit a relaxation in the monthly-to-quarterly testing schedules that seek to verify and assure pump operability. Pump drivers are not included in the current battery of testing. Operational problems thought to be caused by pump degradation were found to be the result of motor degradation. Recent advances in nonintrusive monitoring techniques have made motor diagnostics a viable technology for assessing motor operability. Motor current/power analysis can detect rotor bar degradation and ascertain ranges of hydraulically unstable operation for a particular pump and motor set. The concept of using motor current or power fluctuations as an indicator of pump hydraulic load stability is presented.

  5. A review of proton exchange membrane water electrolysis on degradation mechanisms and mitigation strategies

    Science.gov (United States)

    Feng, Qi; Yuan, Xiao-Zi; Liu, Gaoyang; Wei, Bing; Zhang, Zhen; Li, Hui; Wang, Haijiang

    2017-10-01

    Proton exchange membrane water electrolysis (PEMWE) is an advanced and effective solution to the primary energy storage technologies. A better understanding of performance and durability of PEMWE is critical for the engineers and researchers to further advance this technology for its market penetration, and for the manufacturers of PEM water electrolyzers to implement quality control procedures for the production line or on-site process monitoring/diagnosis. This paper reviews the published works on performance degradations and mitigation strategies for PEMWE. Sources of degradation for individual components are introduced. With degradation causes discussed and degradation mechanisms examined, the review emphasizes on feasible strategies to mitigate the components degradation. To avoid lengthy real lifetime degradation tests and their high costs, the importance of accelerated stress tests and protocols is highlighted for various components. In the end, R&D directions are proposed to move the PEMWE technology forward to become a key element in future energy scenarios.

  6. 76 FR 22729 - Polaris Industries, Including On-Site Leased Workers From Westaff, Supply Technologies, Aerotek...

    Science.gov (United States)

    2011-04-22

    ... Employment and Training Administration Polaris Industries, Including On-Site Leased Workers From Westaff..., applicable to workers of Polaris Industries, including on-site leased workers from Westaff, Osceola... location of Polaris Industries. The Department has determined that these workers were sufficiently under...

  7. 78 FR 48468 - Delphi Corporation, Electronics and Safety Division, Including On-Site Leased Workers From...

    Science.gov (United States)

    2013-08-08

    ... Employment and Training Administration Delphi Corporation, Electronics and Safety Division, Including On-Site... to workers of Delphi Corporation, Electronics and Safety Division, including on-site leased workers... Delphi Corporation, Electronics and Safety Division. The Department has determined that these workers...

  8. The extent of on-site leakage in selected suburbs of Johannesburg ...

    African Journals Online (AJOL)

    This study investigated on-site leakage on 182 properties with relatively new municipal water meters in well-established suburbs of Johannesburg. A methodology was developed to estimate the on-site leakage rate from readings taken from these municipal water meters, which was then adjusted to account for metering ...

  9. 76 FR 14101 - Commercial Furniture Group, Inc., Including On-Site Leased Workers From Staffing Solutions...

    Science.gov (United States)

    2011-03-15

    ... Employment and Training Administration Commercial Furniture Group, Inc., Including On-Site Leased Workers From Staffing Solutions; Morristown, TN; Commercial Furniture Group, Inc., Chicago, IL; Amended..., applicable to workers of Commercial Furniture Group, Inc., including on-site leased workers from Staffing...

  10. 78 FR 19530 - Eastman Kodak Company (GCG), Electrographic Print Solutions, Including On-Site Leased Workers...

    Science.gov (United States)

    2013-04-01

    ... workers from Adecco, Dayton, Ohio, were affected by the shift in production to a foreign country which... On-Site Leased Workers From Adecco and Datrose, Spencerport, New York; Eastman Kodak Company, IPS, Including On-Site Leased Workers From Adecco, Dayton, Ohio; Amended Certification Regarding Eligibility To...

  11. 78 FR 54487 - Abbott Laboratories; Diagnostic-Hematology; Including On-Site Leased Workers From Manpower...

    Science.gov (United States)

    2013-09-04

    ... Employment and Training Administration Abbott Laboratories; Diagnostic--Hematology; Including On-Site Leased... Laboratories, Diagnostic--Hematology division, including on-site leased workers from Manpower Service Group... to the production of hematology reagents and instruments. The company reports that workers leased...

  12. 75 FR 28295 - Cummins Filtration, Including On-Site Leased Workers From Manpower and Spherion Staffing...

    Science.gov (United States)

    2010-05-20

    ... Employment and Training Administration Cummins Filtration, Including On-Site Leased Workers From Manpower and... workers of Cummins Filtration, including on-site leased workers from Manpower, Lake Mills, Iowa. The... engaged in the production of oil and fuel filters, Stratpore media and other metal components for engines...

  13. 75 FR 62423 - Barnstead Thermolyne Corporation, a Subsidiary of Thermo Fisher Scientific, Including On-Site...

    Science.gov (United States)

    2010-10-08

    ... engaged in activities related to the production of scientific laboratory equipment. New information shows...] Barnstead Thermolyne Corporation, a Subsidiary of Thermo Fisher Scientific, Including On-Site Leased Workers... subsidiary of Thermo Fisher Scientific, including on- site leased workers from Sedona Staffing, Dubuque, Iowa...

  14. Isolation of four hydrocarbon effluent-degrading Bacillaceae species ...

    African Journals Online (AJOL)

    Four bacterial strains belonging to the family Bacillaceae were isolated from a polluted site and tested for their efficiency in degrading a refinery effluent highly polluted with hydrocarbons. Among 13 strains isolated, four were selected for their efficiency. Each of these four strains demonstrated a strong ability to grow as a ...

  15. Teores de proteína bruta para bovinos alimentados com feno de capim-tifton 85: parâmetros ruminais, eficiência de síntese microbiana e degradabilidade in situ Effects of crude protein levels on microbial efficiency and in situ degradability in steers fed Tifton 85 bermudagrass hay supplemented with different protein sources

    Directory of Open Access Journals (Sweden)

    Edilane Aparecida da Silva

    2007-02-01

    Full Text Available Avaliou-se o efeito da deficiência de PB na dieta sobre a eficiência de síntese microbiana e a degradabilidade in situ da MS e FDN em novilhos mestiços. Os tratamentos consistiram de dietas compostas de feno de tifton 85 (FN suplementadas com uréia (FNUR, farelo de soja (FNFS e farelo de glúten de milho- 60 (FNGL. Foram utilizados oito novilhos canulados no rúmen e no duodeno, distribuídos em dois quadrados latinos 4 x 4. O pH e a concentração de nitrogênio não-amoniacal (N-NH3 foram mensurados no fluido ruminal antes e 2, 4, 6 e 8 horas após o fornecimento da ração, utilizando-se a fibra em detergente ácido indigestível (FDAi como indicador do fluxo duodenal. A eficiência microbiana foi determinada por meio das bases purinas. Em todas as dietas, o pH e a concentração de N-NH3 foram adequados para o crescimento dos microrganismos ruminais. Não houve efeito da deficiência de PB na dieta sobre a ingestão de MS, a eficiência de síntese microbiana e a cinética de degradação da MS e FDN do feno de tifton 85. O teor de PB das dietas não alterou o crescimento microbiano, a eficiência de síntese microbiana e a cinética de degradação ruminal.Eight crossbred steers fitted with ruminal and duodenal cannulas were randomly assigned to two replicated 4 x 4 Latin squares to evaluate the effects of crude protein (CP levels on microbial protein synthesis efficiency and in situ degradability of nutrients. Animals received a control diet containing Tifton 85 bermudagrass hay or the control diet supplemented with urea, soybean meal or corn gluten meal-60. Ruminal pH and concentration of ruminal ammonia (NH3-N were determined in the ruminal fluid at 0 (pre-feeding, 2, 4, 6 and 8 hours after feeding. Indigestible acid detergent fiber was used as the internal marker for measuring duodenal flow of nutrients while total purines were used as the direct microbial marker to measure microbial protein synthesis and microbial efficiency

  16. On-site Destruction of Radioactive Oily Wastes Using Adsorption Coupled with Electrochemical Regeneration - 12221

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.W. [Arvia Technology Ltd, Daresbury Innovation Centre, Daresbury, WA4 4FS (United Kingdom); Wickenden, D.A. [Magnox Ltd, Berkeley Centre, Gloucestershire, GL13 9PB (United Kingdom); Roberts, E.P.L. [School of Chemical Engineering, University of Manchester, Manchester, M60 1QD (United Kingdom)

    2012-07-01

    Arvia{sup R}, working with Magnox Ltd, has developed the technology of adsorption coupled with electrochemical regeneration for the degradation of orphan radioactive oil wastes. The process results in the complete destruction of the organic phase where the radioactivity is transferred to liquid and solid secondary wastes that can then be processed using existing authorised on-site waste-treatment facilities.. Following on from successful laboratory and pilot scale trials, a full scale, site based demonstrator unit was commissioned at the Magnox Trawsfynydd decommissioning site to destroy 10 l of LLW and ILW radioactive oils. Over 99% of the emulsified oil was removed and destroyed with the majority of activity (80 - 90%) being transferred to the aqueous phase. Secondary wastes were disposed of via existing routes with the majority being disposed of via the sites active effluent treatment plant. The regeneration energy required to destroy a litre of oil was 42.5 kWh/l oil. This on-site treatment approach eliminates the risks and cost associated with transporting the active waste oils off site for incineration or other treatment. The Arvia{sup R} process of adsorption coupled with electrochemical regeneration has successfully demonstrated the removal and destruction of LLW and ILW radioactive oils on a nuclear site. Over 99.9% of the emulsified oil was removed, with the majority of the radioactive species transferred to the aqueous, supernate, phase (typically 80 - 90 %). The exception to this is Cs-137 which appears to be more evenly distributed, with 43% associated with the liquid phase and 33 % with the Nyex, the remainder associated with the electrode bed. The situation with Plutonium may be similar, but this requires confirmation, hence further work is underway to understand the full nature of the electrode bed radioactive burden and its distribution within the body of the electrodes. - Tritium gaseous discharges were negligible; hence no off-gas treatment

  17. TALSPEAK Solvent Degradation

    Energy Technology Data Exchange (ETDEWEB)

    Leigh R. Martin; Bruce J. Mincher

    2009-09-01

    Understanding the radiolytic degradation behavior of organic molecules involved in new or existing schemes for the recycle of used nuclear fuels is of significant interest for sustaining a closed nuclear fuel cycle. Here we have conducted several lines of investigation to begin understanding the effects of radiolysis on the aqueous phase of the TALSPEAK process for the separation of the trivalent lanthanides from the trivalent actinides. Using the 60-Co irradiator at the INL, we have begun to quantify the effects of radiation on the aqueous phase complexants used in this separation technique, and how this will affect the actinide lanthanide separation factor. In addition we have started to develop methodologies for stable product identification, a key element in determining the degradation pathways. We have also introduced a methodology to investigate the effects of alpha radiolysis that has previously received limited attention.

  18. Nylon separators. [thermal degradation

    Science.gov (United States)

    Lim, H. S.

    1977-01-01

    A nylon separator was placed in a flooded condition in K0H solution and heated at various high temperatures ranging from 60 C to 110 C. The weight decrease was measured and the molecular weight and decomposition product were analyzed to determine: (1) the effect of K0H concentration on the hydrolysis rate; (2) the effect of K0H concentration on nylon degradation; (3) the activation energy at different K0H concentrations; and (4) the effect of oxygen on nylon degradation. The nylon hydrolysis rate is shown to increase as K0H concentration is decreased 34%, giving a maximum rate at about 16%. Separator hydrolysis is confirmed by molecular weight decrease in age of the batteries, and the reaction of nylon with molecular oxygen is probably negligible, compared to hydrolysis. The extrapolated rate value from the high temperature experiment correlates well with experimental values at 35 degrees.

  19. Biogeochemical Cycles in Degraded Lands

    Science.gov (United States)

    Davidson, Eric A.; Vieira, Ima Celia G.; ReisdeCarvalho, Claudio Jose; DeanedeAbreuSa, Tatiana; deSouzaMoutinho, Paulo R.; Figueiredo, Ricardo O.; Stone, Thomas A.

    2004-01-01

    The objectives of this project were to define and describe the types of landscapes that fall under the broad category of "degraded lands" and to study biogeochemical cycles across this range of degradation found in secondary forests. We define degraded land as that which has lost part of its capacity of renovation of a productive ecosystem, either in the context of agroecosystems or as native communities of vegetation. This definition of degradation permits evaluation of biogeochemical constraints to future land uses.

  20. Photocatalytic Degradation of Thiram (Fungicides under Visible Light Irradiation

    Directory of Open Access Journals (Sweden)

    Sanjay R. Thakare

    2005-01-01

    Full Text Available Pesticides in the different form are toxic to the environment and removal of its form the various sources is a difficult task. The thiram undergoes photocatalytic degradation under visible light when prepared TiO2∼PVA polymer composite was used as a photocatalyst. The data represent that prepared TiO2∼PVA polymer composite is a more efficient photocatalyst than the neat TiO2. Photocatalytic efficiency of prepared TiO2∼PVA polymer composite was measured in term of no adsorption of pollutant, higher degradation rate and act as a photocatalyst under visible light irradiation. 150 minutes are required for the complete degradation of the thiram. The end products of photocatalytic degradation of thiram are CO2, nitrate and sulphate.

  1. Heterogeneous photocatalytic degradation of rose bengal: Effect of operational parameters

    Science.gov (United States)

    Kaur, Japinder; Singhal, Sonal

    2014-10-01

    The photocatalytic degradation of rose bengal dye has been investigated using ZnO nanoparticles as photocatalyst. ZnO nanoparticles were found to be efficient catalyst for the degradation of dye and 98% degradation was observed in 90 min. Effect of various operational parameters such as amount of catalyst (0.25-2.00 g/L), concentration of dye (0.01-0.05 mM) and pH (3-11) of dye solution on the rate of dye degradation was studied. The most favorable results for the degradation of rose bengal were observed at pH 5 at a catalyst loading of 1 g/L. Moreover, hydroxyl radicals have been detected in the photocatalytic reaction mixture by using terephthalic acid photoluminescence probing technique. The reusability of the catalyst has also been studied and catalyst was found to be active even after being used for 5 times.

  2. Heterogeneous photocatalytic degradation of rose bengal: Effect of operational parameters

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Japinder, E-mail: jap.chawla@gmail.com; Singhal, Sonal, E-mail: sonal1174@gmail.com

    2014-10-01

    The photocatalytic degradation of rose bengal dye has been investigated using ZnO nanoparticles as photocatalyst. ZnO nanoparticles were found to be efficient catalyst for the degradation of dye and 98% degradation was observed in 90 min. Effect of various operational parameters such as amount of catalyst (0.25–2.00 g/L), concentration of dye (0.01–0.05 mM) and pH (3–11) of dye solution on the rate of dye degradation was studied. The most favorable results for the degradation of rose bengal were observed at pH 5 at a catalyst loading of 1 g/L. Moreover, hydroxyl radicals have been detected in the photocatalytic reaction mixture by using terephthalic acid photoluminescence probing technique. The reusability of the catalyst has also been studied and catalyst was found to be active even after being used for 5 times.

  3. A Threshold-based, on-site earthquake early warning approach for Italy

    Science.gov (United States)

    Caruso, Alessandro; Colombelli, Simona; Zollo, Aldo; Kanamori, Hiroo

    2017-04-01

    A real-time strategy for a P-wave based, on-site earthquake early warning system has been developed and tested using the database of Italian earthquakes. The key elements of the proposed methodology are: 1) the real-time, continuous measurement of three peak amplitude parameters (the initial peak of displacement, Pd, velocity, Pv, and acceleration, Pa) along the vertical component of the P-wave signal and 2) their empirical combination to predict the ensuing Peak Ground Velocity at the same site. The observed parameters are compared to prior established threshold values and then converted into a single, dimensionless variable. A local alert level is issued at the recording site as soon as the empirical combination overcomes a given threshold. The three parameters are continuously measured along the recorded signals, starting from the P-wave arrival time, and progressively expanding the time window. A possible risk when using this approach is the inclusion of the S-waves in the analyzed P-wave signal portion, which may lead to an overestimation of the predicted ground shaking level. To minimize the S-wave contamination, an efficient algorithm for the automatic detection of the S-wave arrival time has been included. The algorithm is based on the real-time polarization analysis of the three-component seismogram and on the Singular Value Decomposition (SVD) (Rosenberger, 2010; Amoroso et al., 2012) and is able to distinguish variations in the polarization of the original signal, and to discriminate the dominant P-wave signal from the arrival of later S-wave phases. The performance of the method has been evaluated by defining successful, missed and false alarms, and counting the relative percentage, after applying the approach to a testing catalog of Italian earthquake records. The database we used for the system testing and calibration consists of more than 200 Italian events in a magnitude range 3.5 warning system.

  4. Training courses for pediatric apheresis on site; how apheresis technology transfer can be performed.

    Science.gov (United States)

    Witt, Volker

    2010-10-01

    Apheresis technology for pediatric patients and donors is still cumbersome, it is rare, mostly done in departments specialized for apheresis in adult patients, and therefore the staff is more or less anxious about dealing with especially little pediatric patients or donors. Our center is specialized in pediatrics and has a department for apheresis. We offered training courses for interested centers, which want to use the AMICUS™ system for leukapheresis in small children. In a 1-2 ay course the principles of leukapheresis in very small children were trained. To investigate the reproducibility of this training courses we invited the centers to share their data with us. As a standard we used a formula (C=[(AD):B×0.5]:1000) for predicting the CD34+ cell yield (C) by calculating the yield from total blood volume (D) processed, bodyweight (B), CD34+ cell count in peripheral blood (A) and an assumption of the collection efficiency of 50% (0.5). We hypostasized that the deviation of different centers should be in comparable limits of agreement as our own data. Thirteen centers from Germany, Poland, Ukraine, Romania, Italy, Hungary, and Slovakia asked from 1999 until today for support for pediatric leukapheresis. 6 centers sent 20 case report forms back (9 blood priming, 6 saline priming), from which 15 were completely filled in and available for the evaluation. The data were compared to 129 leukapheresis (41 blood priming, 88 saline priming) performed in our institution. The limit of agreement to the formula was -17.6% (±43) compared to -10.5% (±36). There was no statistically differences by the Mann-Whitney-U-test (p=0.5607). We conclude that training course held on site in different centers in different country could led to reproducible performance of standardized leukapheresis procedures in small children. In the future this could be a way for quality control in pediatric apheresis. Copyright © 2010 Elsevier Ltd. All rights reserved.

  5. Nanoscale zerovalent iron-mediated degradation of DDT in soil.

    Science.gov (United States)

    Han, Yuling; Shi, Nan; Wang, Huifang; Pan, Xiong; Fang, Hua; Yu, Yunlong

    2016-04-01

    Nanoscale zerovalent iron (nZVI)-mediated degradation of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) was investigated in a spiked soil under different conditions (iron sources, iron dosage, soil moisture, temperature, and soil types) and DDT-contaminated field. The degradation efficiency of p,p'-DDT by nZVI and nZVI coated with sodium oleate (SO-nZVI) was much higher than that by nZVI coated with polyimide (PI-nZVI). The rapid degradation of p,p'-DDT by nZVI only occurred in flooded soil. The degradation half-life of p,p'-DDT decreased significantly from 58.3 to 27.6 h with nZVI dosage from 0.5 to 2.0% and from 46.5 to 32.0 h with temperature from 15 to 35 °C. The degradation efficiency of p,p'-DDT by nZVI differed in Jinhua (JH), Jiaxing (JX), Xiaoshan (XS), Huajiachi (HJC), and Heilongjiang (HLJ) soils. A good correlation was found between the degradation half-life of p,p'-DDT and multiple soil properties. The probable nZVI-mediated degradation pathway of p,p'-DDT in soil was proposed as DDT → DDD/DDE → DDNS → DDOH based on the metabolites identified by GC-MS. The in situ degradation efficiency of residual DDTs in a contaminated field was profoundly enhanced by the addition of nZVI as compared to the control. It is concluded that nZVI might be an efficient agent for the remediation of DDT-contaminated soil under anaerobic environment.

  6. Carbofuran Degradation by Biogenic Manganese Oxides.

    Science.gov (United States)

    Liu, Zhiqiang; Wang, Jia; Qian, Shuai; Wang, Gejiao; Wang, Jinling; Liao, Shuijiao

    2017-03-01

    This work studied the effect of biogenic manganese oxides (Bio-MnOx) on carbofuran degradation.The results showed that 21.05 % and 90.63 % carbofuran, respectively, were degraded in 4 days by Bio-MnOx with and without NaN3 at initial pH 4.80, whereas carbofuran was hardly degraded by chemical manganese oxides in the same condition. Bio-MnOx promoted carbofuran hydrolysis by changing the pH of the environment and encouraged carbofuran phenol cleavage by its oxidization. Both the oxidation of carbofuran phenol by Bio-MnOx and the reoxidation of the released Mn(II) by Mn(II)-oxidizing microorganisms ensured the continuous reactivity of Bio-MnOx and prevented the secondary pollution of Mn(II). Carbofuran phenol was the major transformation product in the degradation and was further oxidized into small organic molecules as monitored by a GC/MS analyzer. This report offers an efficient, feasible, and no-secondary-pollution approach to controlling carbofuran pollution.

  7. Statistical modeling for degradation data

    CERN Document Server

    Lio, Yuhlong; Ng, Hon; Tsai, Tzong-Ru

    2017-01-01

    This book focuses on the statistical aspects of the analysis of degradation data. In recent years, degradation data analysis has come to play an increasingly important role in different disciplines such as reliability, public health sciences, and finance. For example, information on products’ reliability can be obtained by analyzing degradation data. In addition, statistical modeling and inference techniques have been developed on the basis of different degradation measures. The book brings together experts engaged in statistical modeling and inference, presenting and discussing important recent advances in degradation data analysis and related applications. The topics covered are timely and have considerable potential to impact both statistics and reliability engineering.

  8. Protein degradation systems in platelets.

    Science.gov (United States)

    Kraemer, B F; Weyrich, A S; Lindemann, S

    2013-11-01

    Protein synthesis and degradation are essential processes that allow cells to survive and adapt to their surrounding milieu. In nucleated cells, the degradation and/or cleavage of proteins is required to eliminate aberrant proteins. Cells also degrade proteins as a mechanism for cell signalling and complex cellular functions. Although the last decade has convincingly shown that platelets synthesise proteins, the roles of protein degradation in these anucleate cytoplasts are less clear. Here we review what is known about protein degradation in platelets placing particular emphasis on the proteasome and the cysteine protease calpain.

  9. Degradation measurement and analysis for cells and stacks

    Science.gov (United States)

    Gemmen, Randall S.; Williams, Mark C.; Gerdes, Kirk

    Past research in solid oxide fuel cell (SOFC) performance assessment and improvement has focused on cell operating voltage (efficiency). Related to this metric, but distinct and equally important, is performance degradation. This paper examines cell degradation, provides key definitions needed for its characterization, and discusses the relationship of various cell performance variables. To characterize degradation, two parameters are defined, namely, area-specific resistance (ASR), and degradation rate (DR). The ASR of a cell/stack increases as a result of degradation, and therefore needs to be modeled as a time-dependent parameter. A model for SOFC cell performance is used to describe polarization losses, and to predict degradation performance. The model is then used to demonstrate the use of ASR and DR in the assessment of degradation. Available experimental data is separately used to do the same. ASR is shown to be insensitive to certain variations in test conditions and therefore is the preferred parameter for fuel cell developers when comparing performance differences arising from incremental changes in design/materials. DR is the preferred parameter for determining changes in efficiency over the lifetime of the cell/stack, which is a key concern for end users.

  10. Tebuconazole photocatalytic degradation kinetics

    OpenAIRE

    Prestes, Thiago de Hermann; Gibbon, Danielle de Oliveira; Lansarin, Marla Azário; Moro, Celso Camilo

    2010-01-01

    The tebuconazole photocatalytic degradation kinetics was studied in a batch reactor using TiO2 (P25-Degussa) as catalyst and a high pressure mercury lamp. The photolysis, adsorption and irradiation effects in the reaction rate were evaluated. Afterward, the suspension catalyst concentration and initial pH to the maximum reaction rate was determined. It was observed that the reaction rate can be approached by a pseudo-first order, with a maximum kinetics constant at 260 mg L-1catalyst concentr...

  11. Outdoor PV Degradation Comparison

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, D. C.; Smith, R. M.; Osterwald, C. R.; Gelak, E.; Kurtz, S. R.

    2011-02-01

    As photovoltaic (PV) penetration of the power grid increases, it becomes vital to know how decreased power output; may affect cost over time. In order to predict power delivery, the decline or degradation rates must be determined; accurately. At the Performance and Energy Rating Testbed (PERT) at the Outdoor Test Facility (OTF) at the; National Renewable Energy Laboratory (NREL) more than 40 modules from more than 10 different manufacturers; were compared for their long-term outdoor stability. Because it can accommodate a large variety of modules in a; limited footprint the PERT system is ideally suited to compare modules side-by-side under the same conditions.

  12. Short-time alkaline peroxide pretreatment for rapid pulping and efficient enzymatic hydrolysis of rice straw.

    Science.gov (United States)

    Hideno, Akihiro

    2017-04-01

    To improve utilization of agricultural residues in biorefineries, the effects of alkaline peroxide (AP) pretreatment on thermal degradation and enzymatic digestibility of rice straw were investigated. A high-cellulose (>70%) pulp with a width of a few micrometers was obtained by rapid (10min) treatment with AP, without prior heating or other treatment. Moreover, enzymatic hydrolysis of the pulp produced a high glucose yield (approximately 80%). Microfibril networks were exposed, and many nano-scale pores that are easily penetrated by cellulases were observed on the surface of the AP-treated sample. For enzymatic hydrolysis of the pulp, increasing the dosage of cellulases was more effective for improving the glucose yield than addition of a grinding treatment. This AP treatment has the potential for on-site application because it is simple, highly efficient, and can be performed in a short time. Copyright © 2017. Published by Elsevier Ltd.

  13. Electrochemical degradation and mineralization of glyphosate herbicide.

    Science.gov (United States)

    Tran, Nam; Drogui, Patrick; Doan, Tuan Linh; Le, Thanh Son; Nguyen, Hoai Chau

    2017-12-01

    The presence of herbicide is a concern for both human and ecological health. Glyphosate is occasionally detected as water contaminants in agriculture areas where the herbicide is used extensively. The removal of glyphosate in synthetic solution using advanced oxidation process is a possible approach for remediation of contaminated waters. The ability of electrochemical oxidation for the degradation and mineralization of glyphosate herbicide was investigated using Ti/PbO 2 anode. The current intensity, treatment time, initial concentration and pH of solution are the influent parameters on the degradation efficiency. An experimental design methodology was applied to determine the optimal condition (in terms of cost/effectiveness) based on response surface methodology. Glyphosate concentration (C 0  = 16.9 mg L -1 ) decreased up to 0.6 mg L -1 when the optimal conditions were imposed (current intensity of 4.77 A and treatment time of 173 min). The removal efficiencies of glyphosate and total organic carbon were 95 ± 16% and 90.31%, respectively. This work demonstrates that electrochemical oxidation is a promising process for degradation and mineralization of glyphosate.

  14. Real-time and on-site γ-ray radiation response testing system for semiconductor devices and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Mu, Yifei, E-mail: Y.Mu@student.liverpool.ac.uk [Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ (United Kingdom); Zhao, Ce Zhou, E-mail: cezhou.zhao@xjtlu.edu.cn [Department of Electrical and Electronic Engineering, Xi’an Jiaotong-Liverpool University, Suzhou 215123 (China); Qi, Yanfei, E-mail: yanfei.qi01@xjtlu.edu.cn [Department of Electrical and Electronic Engineering, Xi’an Jiaotong-Liverpool University, Suzhou 215123 (China); Lam, Sang, E-mail: s.lam@xjtlu.edu.cn [Department of Electrical and Electronic Engineering, Xi’an Jiaotong-Liverpool University, Suzhou 215123 (China); Zhao, Chun, E-mail: garyzhao@ust.hk [Nano and Advanced Materials Institute, Hong Kong University of Science and Technology, Kowloon (Hong Kong); Lu, Qifeng, E-mail: qifeng@liverpool.ac.uk [Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ (United Kingdom); Cai, Yutao, E-mail: yutao.cai@xjtlu.edu.cn [Department of Electrical and Electronic Engineering, Xi’an Jiaotong-Liverpool University, Suzhou 215123 (China); Mitrovic, Ivona Z., E-mail: ivona@liverpool.ac.uk [Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ (United Kingdom); Taylor, Stephen, E-mail: s.taylor@liverpool.ac.uk [Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ (United Kingdom); Chalker, Paul R., E-mail: pchalker@liverpool.ac.uk [Center for Materials and Structures, School of Engineering, University of Liverpool, Liverpool L69 3GH (United Kingdom)

    2016-04-01

    The construction of a turnkey real-time and on-site radiation response testing system for semiconductor devices is reported. Components of an on-site radiation response probe station, which contains a 1.11 GBq Cs{sup 137} gamma (γ)-ray source, and equipment of a real-time measurement system are described in detail for the construction of the whole system. The real-time measurement system includes a conventional capacitance–voltage (C–V) and stress module, a pulse C–V and stress module, a conventional current–voltage (I–V) and stress module, a pulse I–V and stress module, a DC on-the-fly (OTF) module and a pulse OTF module. Electrical characteristics of MOS capacitors or MOSFET devices are measured by each module integrated in the probe station under continuous γ-ray exposure and the measurement results are presented. The dose rates of different gate dielectrics are calculated by a novel calculation model based on the Cs{sup 137} γ-ray source placed in the probe station. For the sake of operators’ safety, an equivalent dose rate of 70 nSv/h at a given operation distance is indicated by a dose attenuation model in the experimental environment. HfO{sub 2} thin films formed by atomic layer deposition are employed to investigate the radiation response of the high-κ material by using the conventional C–V and pulse C–V modules. The irradiation exposure of the sample is carried out with a dose rate of 0.175 rad/s and ±1 V bias in the radiation response testing system. Analysis of flat-band voltage shifts (ΔV{sub FB}) of the MOS capacitors suggests that the on-site and real-time/pulse measurements detect more serious degradation of the HfO{sub 2} thin films compared with the off-site irradiation and conventional measurement techniques.

  15. Comparison of conventional vs. modular hydrogen refueling stations and on-site production vs. delivery.

    Energy Technology Data Exchange (ETDEWEB)

    Hecht, Ethan S. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Pratt, Joseph William [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2017-03-01

    To meet the needs of public and private stakeholders involved in the development, construction, and operation of hydrogen fueling stations needed to support the widespread roll-out of hydrogen fuel cell electric vehicles, this work presents publicly available station templates and analyses. These ‘Reference Stations’ help reduce the cost and speed the deployment of hydrogen stations by providing a common baseline with which to start a design, enable quick assessment of potential sites for a hydrogen station, identify contributors to poor economics, and suggest areas of research. This work presents layouts, bills of materials, piping and instrumentation diagrams, and detailed analyses of five new station designs. In the near term, delivered hydrogen results in a lower cost of hydrogen compared to on-site production via steam methane reforming or electrolysis, although the on-site production methods have other advantages. Modular station concepts including on-site production can reduce lot sizes from conventional assemble-on-site stations.

  16. Towards sustainable and robust on-site domestic wastewater treatment for all citizens

    NARCIS (Netherlands)

    Mgana, S.

    2003-01-01

    In most developing countries commonly practiced domestic wastewater treatment systems predominantly constitute anaerobic treatment process. The anaerobic treatment units mostly installed are on-site at residential dwellings.However the commonly installed units, viz., traditional pit latrines and

  17. Stream habitat connectivity in the Canadian Arctic: an on-site approach to design and construction

    National Research Council Canada - National Science Library

    Baki, Abul Basar M; Zhu, David Z; Tonn, William M; Cahill, Christopher L; Courtice, Gregory J

    2016-01-01

    We developed a successful on-site approach for design and construction of stream modifications that addressed challenging remote-site conditions of limited field data and available construction materials...

  18. 78 FR 8587 - Thomson Reuters, Finance Operations & Technology Division, Including On-Site Leased Workers From...

    Science.gov (United States)

    2013-02-06

    ... Employment and Training Administration Thomson Reuters, Finance Operations & Technology Division, Including... Worker Adjustment Assistance on August 2, 2012, applicable to workers of Thomson Reuters, Finance... that workers of Thomson Reuters, Finance Operations & Technology Division, including on-site leased...

  19. Wilderness Recreation Demand: A Comparison of Travel Cost and On-Site Cost Models

    Science.gov (United States)

    J.M. Bowker; A. Askew; L. Seymour; J.P. Zhu; D. English; C.M. Starbuck

    2009-01-01

    This study used travel cost and on-site day cost models, coupled with the Forest Service’s National Visitor Use Monitoring data, to examine the demand for and value of recreation access to designated Wilderness.

  20. On-site toxicity of irrigation drainwater from Stillwater National Wildlife Refuge to aquatic organisms

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The toxicity of water from seven locations in the Stillwater Wildlife Management Area was evaluated in a series of on-site tests conducted over a 10 day period with...

  1. A sensitive rapid on-site immunoassay for heavy metal contamination

    Energy Technology Data Exchange (ETDEWEB)

    Blake, R.; Blake, D.; Flowers, G.

    1996-05-02

    This project concerns the development of immunoassays for heavy metals that will permit the rapid on-site analysis of specific heavy metals, including lead and chromium in water and soil samples. 2 refs.

  2. AMCO On-Site Air Monitoring Map Service, Oakland CA, Live 2017, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — This map service contains the following layers: All On-Site Air Monitors, TCE, PCE, and Vinyl Chloride. The layers draws at all scales. Full FGDC metadata for the...

  3. 78 FR 12358 - UBS Financial Services, Inc., Wealth Management Americas Operations, Including On-Site Leased...

    Science.gov (United States)

    2013-02-22

    ... Employment and Training Administration UBS Financial Services, Inc., Wealth Management Americas Operations..., applicable to workers of UBS Financial Services, Inc., Wealth Management Americas Operations (UBS), Weehawken... Management Americas Operations, including on-site leased workers from Leafstone, Cognizant Technology...

  4. On-Site Additive Manufacturing by Selective Laser Melting of Composite Objects

    Science.gov (United States)

    Fateri, M.; Khosravi, M.

    2012-06-01

    This paper proposes a method for cost reduction of future space missions by manufacturing parts on foreign planets. The suitability of Selective Laser Melting process for on-site production of metallic, ceramic and glass products on mars is examined.

  5. Efficient k-NN search on vertically decomposed data

    NARCIS (Netherlands)

    A.P. de Vries (Arjen); N. Mamoulis; N.J. Nes (Niels); M.L. Kersten (Martin)

    2002-01-01

    textabstractApplications like multimedia retrieval require efficient support for similarity search on large data collections. Yet, nearest neighbor search is a difficult problem in high dimensional spaces, rendering efficient applications hard to realize: index structures degrade rapidly with

  6. Photoassisted Degradation of a Herbicide Derivative, Dinoseb, in Aqueous Suspension of Titania

    Directory of Open Access Journals (Sweden)

    Niyaz A. Mir

    2012-01-01

    Full Text Available The titanium dioxide (TiO2 photoassisted degradation of herbicide dinoseb has been examined in aqueous suspensions under UV light irradiation. The degradation kinetics were studied under various conditions such as substrate concentration, type of catalyst, catalyst dosage, pH, and light intensity as well as in presence of electron acceptors such as hydrogen peroxide, potassium bromate, and potassium persulphate under continuous air purging, and the degradation rates were found to be strongly influenced by these parameters. The Degussa P25 was found to be more efficient photocatalyst as compared to other photocatalysts tested. Dinoseb was found to degrade efficiently in acidic pH and all the electron acceptors studied enhanced the degradation rate. The results manifested that the photocatalysis of dinoseb followed pseudo-first-order kinetics. A qualitative study of the degradation products generated during the process was performed by GC-MS, and a degradation mechanism was proposed.

  7. Degradation of industrial surfactants by photocatalysis combined with ozonation.

    Science.gov (United States)

    Zsilák, Zoltán; Fónagy, Orsolya; Szabó-Bárdos, Erzsébet; Horváth, Ottó; Horváth, Krisztián; Hajós, Péter

    2014-10-01

    The efficiency of titanium dioxide-mediated photocatalytic degradation of pollutants can be enhanced by combination with another advanced oxidation procedure such as ozonation. Mineralization of hydroxy- and dihydroxybenzenesulfonate based on these methods, both individually and combined, was investigated by monitoring the total organic carbon content, sulfate concentration, pH, high-performance liquid chromatography as well as the absorption spectral changes. The mineralization efficiency of the combined procedure significantly exceeded the sum of those of the individual techniques. The comparison of the disappearance of the starting material and the formation of the sulfate ions indicates that desulfonation is not the primary step of the degradation. Moreover, in the case of the combined method, ring cleavage, and thus, partial mineralization can occur without desulfonation. Efficient degradation of other, widely used industrial surfactants, such as alkylbenzene sulfonates and alkyl ether sulfates, was also achieved by heterogeneous photocatalysis combined with ozonation, offering an applicable method for the removal of these pollutants.

  8. On-site and laboratory evaluations of soundscape quality in recreational urban spaces.

    Science.gov (United States)

    Bjerre, Lærke C; Larsen, Thea M; Sørensen, A Josefine; Santurette, Sébastien; Jeong, Cheol-Ho

    2017-01-01

    Regulations for quiet urban areas are typically based on sound level limits alone. However, the nonacoustic context may be crucial for subjective soundscape quality. This study aimed at comparing the role of sound level and nonacoustic context for subjective urban soundscape assessment in the presence of the full on-site context, the visual context only, and without context. Soundscape quality was evaluated for three recreational urban spaces by using four subjective attributes: loudness, acceptance, stressfulness, and comfort. The sound level was measured at each site and simultaneous sound recordings were obtained. Participants answered questionnaires either on site or during laboratory listening tests, in which the sound recordings were presented with or without each site's visual context consisting of two pictures. They rated the four subjective attributes along with their preference toward eight sound sources. The sound level was found to be a good predictor of all subjective parameters in the laboratory, but not on site. Although all attributes were significantly correlated in the laboratory setting, they did not necessarily covary on site. Moreover, the availability of the visual context in the listening experiment had no significant effect on the ratings. The participants were overall more positive toward natural sound sources on site. The full immersion in the on-site nonacoustic context may be important when evaluating overall soundscape quality in urban recreational areas. Laboratory evaluations may not fully reflect how subjective loudness, acceptance, stressfulness, and comfort are affected by sound level.

  9. Addressing proteolytic efficiency in enzymatic degradation therapy for celiac disease

    Czech Academy of Sciences Publication Activity Database

    Rey, M.; Yang, M.; Lee, L.; Zhang, Y.; Sheff, J.G.; Sensen, Ch. W.; Mrázek, Hynek; Halada, Petr; Man, Petr; McCarville, J.L.; Verdu, E. F.; Schriemer, D. C.

    2016-01-01

    Roč. 6, AUG 2 (2016), s. 30980 ISSN 2045-2322 R&D Projects: GA MŠk(CZ) LO1509; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388971 Keywords : EXCHANGE MASS-SPECTROMETRY * ASPARTIC PROTEASE NEPENTHESIN-1 * GLUTEN-FREE DIET Subject RIV: EE - Microbiology, Virology Impact factor: 4.259, year: 2016

  10. Patterns of efficiency and degradation of composite polymer solar cells

    NARCIS (Netherlands)

    Jeranko, T; Tributsch, H; Sariciftci, NS; Hummelen, JC

    2004-01-01

    Bulk-heterojunction plastic solar cells (PSC) produced from a conjugated polymer, poly(2-methoxy-5-(3',7'-dimethyloctyl-oxy)-1,4-phenylenevinylene) (MDMO-PPV), and a methanofullerene [6,6]-phenyl C-61-butyric acid methyl ester (PCBM) were investigated using photocurrent imaging techniques to

  11. Protein misfolding and degradation in genetic diseases

    DEFF Research Database (Denmark)

    Bross, P; Corydon, T J; Andresen, B S

    1999-01-01

    Investigations of genetic diseases such as cystic fibrosis, alpha-1-antitrypsin deficiency, phenylketonuria, mitochondrial acyl-CoA dehydrogenase deficiencies, and many others have shown that enhanced proteolytic degradation of mutant proteins is a common molecular pathological mechanism. Detailed....... This appears to be the case for many missense mutations and short in-frame deletions or insertions that represent a major fraction of the mutations detected in genetic diseases. In some diseases, or under some circumstances, the degradation system is not efficient. Instead, aberrant folding leads...... in which proteins fold. Within the context of genetic diseases, we review knowledge on the molecular processes underlying protein quality control in the various subcellular compartments. The important impact of such systems for variability of the expression of genetic deficiencies is emphasised....

  12. Bacterial Cellulose Hydrolysis in Anaerobic Environmental Subsystems—Clostridium thermocellumandClostridium stercorarium, Thermophilic Plant‐fiber Degraders

    National Research Council Canada - National Science Library

    Zverlov, Vladimir V; Schwarz, Wolfgang H

    2008-01-01

    Cellulose degradation is a rare trait in bacteria. However, the truly cellulolytic bacteria are extremely efficient hydrolyzers of plant cell wall polysaccharides, especially those in thermophilic anaerobic ecosystem...

  13. Develop and test fuel cell powered on-site integrated total energy systems: Phase 3: Full-scale power plant development

    Science.gov (United States)

    1982-01-01

    The development of a commercially viable and cost-effective phospheric acid fuel cell powered on-site integrated energy system (OS/IES) is described. The fuel cell offers energy efficients in the range of 35-40% of the higher heating value of available fuels in the form of electrical energy. In addition, by utilizing the thermal energy generated for heating, ventilating and air-conditioning (HVAC), a fuel cell OS/IES could provide total energy efficiencies in the neighborhood of 80%. Also, the Engelhard fuel cell OS/IES offers the important incentive of replacing imported oil with domestically produced methanol, including coal-derived methanol.

  14. Restoring Soil Quality to Mitigate Soil Degradation

    Directory of Open Access Journals (Sweden)

    Rattan Lal

    2015-05-01

    Full Text Available Feeding the world population, 7.3 billion in 2015 and projected to increase to 9.5 billion by 2050, necessitates an increase in agricultural production of ~70% between 2005 and 2050. Soil degradation, characterized by decline in quality and decrease in ecosystem goods and services, is a major constraint to achieving the required increase in agricultural production. Soil is a non-renewable resource on human time scales with its vulnerability to degradation depending on complex interactions between processes, factors and causes occurring at a range of spatial and temporal scales. Among the major soil degradation processes are accelerated erosion, depletion of the soil organic carbon (SOC pool and loss in biodiversity, loss of soil fertility and elemental imbalance, acidification and salinization. Soil degradation trends can be reversed by conversion to a restorative land use and adoption of recommended management practices. The strategy is to minimize soil erosion, create positive SOC and N budgets, enhance activity and species diversity of soil biota (micro, meso, and macro, and improve structural stability and pore geometry. Improving soil quality (i.e., increasing SOC pool, improving soil structure, enhancing soil fertility can reduce risks of soil degradation (physical, chemical, biological and ecological while improving the environment. Increasing the SOC pool to above the critical level (10 to 15 g/kg is essential to set-in-motion the restorative trends. Site-specific techniques of restoring soil quality include conservation agriculture, integrated nutrient management, continuous vegetative cover such as residue mulch and cover cropping, and controlled grazing at appropriate stocking rates. The strategy is to produce “more from less” by reducing losses and increasing soil, water, and nutrient use efficiency.

  15. Enhanced bioelectroremediation of a complexly contaminated river sediment through stimulating electroactive degraders with methanol supply.

    Science.gov (United States)

    Zhao, Youkang; Li, Zhiling; Ma, Jincai; Yun, Hui; Qi, Mengyuan; Ma, Xiaodan; Wang, Hao; Wang, Aijie; Liang, Bin

    2018-05-05

    Bioelectroremediation is an efficient, sustainable, and environment-friendly remediation technology for the complexly contaminated sediments. Although various recalcitrant pollutants could be degraded in the electrode district, the degradation efficiency was generally confined by the low total organic carbon (TOC) content in the sediment. How to enhance the electroactive degraders' activity and efficiency remain poorly understood. Here we investigated the bioeletroremediation of a complexly contaminated river sediment with low TOC in a cylindric sediment microbial fuel cell stimulated by methanol. After 200 days treatment, the degradation efficiencies of total petroleum hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAH), and cycloalkenes (CYE) in the electrode district with methanol stimulation were 1.45-4.38 times higher compared with those in the non-electrode district without methanol stimulation. The overall electrode district communities were significantly positively correlated with the variables of the enhanced TPH, PAH, CYE and TOC degradation efficiencies (p methanol stimulation selectively enriched electroactive degraders (Geobacter and Desulfobulbus) in the anode biofilms, and their proportion was markedly positively correlated with the characteristic and total pollutants degradation efficiencies (p < .001). This study offers a new insight into the response of key electroactive degraders to the joint stimulation process. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. On-Site Energy Management by Integrating Campus Buildings and Optimizing Local Energy Systems, Case Study of the Campus in Finland

    Directory of Open Access Journals (Sweden)

    Genku Kayo

    2016-12-01

    Full Text Available This research work describes the potential study on the impact of energy improvements of existing campus buildings by on-site energy management and operational strategies. The focus buildings in the campus are mainly built in the 1960s, and therefore it is time to carry out renovation work. In connection with renovations, the aim is to improve the energy efficiency of the buildings, and to develop the functionality of the properties to meet the current requirements. Thus, in this study, the potentials of on-site energy generation and sharing in the cluster of campus buildings in Finland were studied. By means of optimisation method, the optimal combined heat and power systems (CHP capacity distribution and operation mode for minimizing annual primary energy consumption were simulated. The results show the integration of buildings has advantage for on-site energy management as 23% of primary energy reduction compared with current situation. Consequently, integrating buildings and optimizing on-site energy management can be one of effective strategies for minimizing primary energy consumption. Furthermore, the study to improve operation strategies of building service system considering current space use in the building clarified that up to 13% of total energy use reduction is expected. The research work also proposes the way of providing environmental information to increase awareness of building energy usage in the campus.

  17. Thermal battery degradation mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Missert, Nancy A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Brunke, Lyle Brent [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Diffuse reflectance IR spectroscopy (DRIFTS) was used to investigate the effect of accelerated aging on LiSi based anodes in simulated MC3816 batteries. DRIFTS spectra showed that the oxygen, carbonate, hydroxide and sulfur content of the anodes changes with aging times and temperatures, but not in a monotonic fashion that could be correlated to phase evolution. Bands associated with sulfur species were only observed in anodes taken from batteries aged in wet environments, providing further evidence for a reaction pathway facilitated by H2S transport from the cathode, through the separator, to the anode. Loss of battery capacity with accelerated aging in wet environments was correlated to loss of FeS2 in the catholyte pellets, suggesting that the major contribution to battery performance degradation results from loss of active cathode material.

  18. Environmental degradation in biocomposites

    CSIR Research Space (South Africa)

    John, Maya J

    2017-06-01

    Full Text Available properties which occurs due to degradation of fibres and matrix. In the case of biocomposites, both natural fibres and the polymer matrix absorb the ultraviolet rays from the sun- light. This leads to changes in the chemical structure of the polymers via... a S ta ge : P ro of C ha pt er N o. : 7 T itl e N am e: R ay P ag e N um be r: 1 D at e: 0 2/ 02 /2 01 7 T im e: 0 1: 14 :0 4 B978-0-08-100793-8.00007-7, 00007 Ray, 978-0-08-100793-8 AUTHOR QUERY FORM Book: Biocomposites for High...

  19. Enhancement of Cellulose Degradation by Cattle Saliva

    Science.gov (United States)

    Seki, Yasutaka; Kikuchi, Yukiko; Kimura, Yoshihiro; Yoshimoto, Ryo; Takahashi, Masatoshi; Aburai, Kenichi; Kanai, Yoshihiro; Ruike, Tatsushi; Iwabata, Kazuki; Sugawara, Fumio; Sakai, Hideki; Abe, Masahiko; Sakaguchi, Kengo

    2015-01-01

    Saccharification of cellulose is a promising technique for producing alternative source of energy. However, the efficiency of conversion of cellulose into soluble sugar using any currently available methodology is too low for industrial application. Many additives, such as surfactants, have been shown to enhance the efficiency of cellulose-to-sugar conversion. In this study, we have examined first whether cattle saliva, as an additive, would enhance the cellulase-catalyzed hydrolysis of cellulose, and subsequently elucidated the mechanism by which cattle saliva enhanced this conversion. Although cattle saliva, by itself, did not degrade cellulose, it enhanced the cellulase-catalyzed degradation of cellulose. Thus, the amount of reducing sugar produced increased approximately 2.9-fold by the addition of cattle saliva. We also found that non-enzymatic proteins, which were present in cattle saliva, were responsible for causing the enhancement effect. Third, the mechanism of cattle saliva mediated enhancement of cellulase activity was probably similar to that of the canonical surfactants. Cattle saliva is available in large amounts easily and cheaply, and it can be used without further purification. Thus, cattle saliva could be a promising additive for efficient saccharification of cellulose on an industrial scale. PMID:26402242

  20. Geophysical detection of on-site wastewater plumes in the North Carolina Coastal Plain, USA

    Science.gov (United States)

    Smith, Matthew

    Nonpoint source pollution (NPS) continues to be the leading cause of water quality degradation in the United States. On-site wastewater systems (OWS) contribute to NPS; however, due to the range of system designs and complexity of the subsurface, OWS contributions to groundwater pollution are not well understood. As the population of coastal North Carolina continues to increase, better methods to locate and characterize wastewater impacted groundwater are needed. Previous studies have demonstrated the ability of non-intrusive geophysical methods to provide high resolution information on various contaminants in different geologic settings. The goals of this study were to evaluate the utility of ground penetrating radar (GPR) and capacitively coupled resistivity (CCR) for detecting OWS components, delineating associated wastewater plumes, and monitoring temporal variations in groundwater quality. Cross-sectional and three dimensional (3D) geophysical surveys were conducted periodically over a one year period (February 2011--January 2012) at two schools utilizing OWS in the lower Neuse River Basin (NRB) in the North Carolina Coastal Plain (NCCP). Cores were collected at both study sites; as well as monthly groundwater depth, temperature, and specific conductivity measurements to better constrain the geophysical interpretations. Additionally, dissolved inorganic nitrogen (DIN) and Cl concentrations were monitored bi-monthly to assess nutrient transport at the sites. The 3D GPR surveys effectively located the wastewater drainage trenches at both sites, in close agreement with locations described in as-built OWS blueprints. Regression analysis of resistivity versus groundwater specific conductivity revealed an inverse relationship, suggesting resistivity ≤ 250 ohm.m was indicative of wastewater impacted groundwater at both sites. The 3D resistivity models identified regions of low resistivity beneath the drainfields relative to background values. Regression analysis of

  1. Slope stability and bearing capacity of landfills and simple on-site test methods.

    Science.gov (United States)

    Yamawaki, Atsushi; Doi, Yoichi; Omine, Kiyoshi

    2017-07-01

    This study discusses strength characteristics (slope stability, bearing capacity, etc.) of waste landfills through on-site tests that were carried out at 29 locations in 19 sites in Japan and three other countries, and proposes simple methods to test and assess the mechanical strength of landfills on site. Also, the possibility of using a landfill site was investigated by a full-scale eccentric loading test. As a result of this, landfills containing more than about 10 cm long plastics or other fibrous materials were found to be resilient and hard to yield. An on-site full scale test proved that no differential settlement occurs. The repose angle test proposed as a simple on-site test method has been confirmed to be a good indicator for slope stability assessment. The repose angle test suggested that landfills which have high, near-saturation water content have considerably poorer slope stability. The results of our repose angle test and the impact acceleration test were related to the internal friction angle and the cohesion, respectively. In addition to this, it was found that the air pore volume ratio measured by an on-site air pore volume ratio test is likely to be related to various strength parameters.

  2. Pi-EEWS: a low cost prototype for on-site earthquake early warning system

    Science.gov (United States)

    Pazos, Antonio; Vera, Angel; Morgado, Arturo; Rioja, Carlos; Davila, Jose Martin; Cabieces, Roberto

    2017-04-01

    The Royal Spanish Navy Observatory (ROA), with the participation of the Cadiz University (UCA), have been developed the ALERTES-SC3 EEWS (regional approach) based on the SeisComP3 software package. This development has been done in the frame of the Spanish ALERT-ES (2011-2013) and ALERTES-RIM (2014-2016) projects, and now a days it is being tested in real time for south Iberia. Additionally, the ALERTES-SC3 system integrates an on-site EEWS software, developed by ROA-UCA, which is running for testing in real time in some seismic broad band stations of the WM network. Regional EEWS are not able to provide alerts in the area closet to the epicentre (blind zone), so a dense on-site EEWS is necessary. As it was mentioned, ALERTES-SC3 inludes the on-site software running on several WM stations but a more dense on-site stations are necessary to cover the blind zones. In order to densify this areas, inside of the "blind zones", a low cost on-site prototype "Pi-EEWS", based on a Raspberry Pi card and low cost acelerometers. In this work the main design ideas, the components and its capabilities will be shown.

  3. Assessment of On-Site Power Opportunities in the Industrial Sector

    Energy Technology Data Exchange (ETDEWEB)

    Bryson, T.

    2001-10-08

    The purpose of this report is to identify the potential for on-site power generation in the U.S. industrial sector with emphasis on nine industrial groups called the ''Industries of the Future'' (IOFs) by the U.S. Department of Energy (DOE). Through its Office of Industrial Technologies (OIT), the DOE has teamed with the IOFs to develop collaborative strategies for improving productivity, global competitiveness, energy usage and environmental performance. Total purchases for electricity and steam for the IOFs are in excess of $27 billion annually. Energy-related costs are very significant for these industries. The nine industrial groups are (1) Agriculture (SIC 1); (2) Forest products; (3) Lumber and wood products (SIC 24); (4) Paper and allied products (SIC 26); (5) Mining (SIC 11, 12, 14); (6) Glass (SIC 32); (7) Petroleum (SIC 29); (8) Chemicals (SIC 28); and (9) Metals (SIC 33): Steel, Aluminum, and Metal casting. Although not currently part of the IOF program, the food industry is included in this report because of its close relationship to the agricultural industry and its success with on-site power generation. On-site generation provides an alternative means to reduce energy costs, comply with environmental regulations, and ensure a reliable power supply. On-site generation can ease congestion in the local utility's electric grid. Electric market restructuring is exacerbating the price premium for peak electricity use and for reliability, creating considerable market interest in on-site generation.

  4. Evaluation of snow-glide risk by modelling and on-site assessment

    Science.gov (United States)

    Leitinger, Georg; Meusburger, Katrin; Rüdisser, Johannes; Tasser, Erich; Höller, Peter

    2015-04-01

    Abandonment of agricultural practices on alpine grasslands lead to increasing snow-glide intensities due to lower surface roughness of the vegetation. Beneath the danger of snow-glide avalanches snow gliding leads to soil erosion and damaging of young trees at afforested sites. Especially in high altitudes afforestation is important to protect settlements and infrastructure against snow-gliding and glide avalanches. Snow-glide damages are therefore of particular danger for these afforestation sites. In the light of future climate change and warmer winter periods, studies already state increasing snow-glide risk and the occurrence of glide avalanches. This study presents an approach to evaluate snow-glide risk by combining the refined Spatial Snow Glide Model (SSGM) first published by Leitinger et al. (2008) and the Guidelines to Identify Snow-Glide Areas (GISGA) proposed by Höller (2012), an on-site risk analyses approach. First, GISGA was validated on the basis of corresponding snow-glide measurements. Second, a potential snow-glide map for an area in the Eastern Alps covering 20000 km² was modelled. The results revealed considerable areas of high snow-glide risk. Using the average amount of winter precipitation between 1990 and 2010 in the SSGM shows higher vulnerability for the northern part of the study area (Tyrol, Austria) than in the southern part (South Tyrol, Italy) because of lower winter precipitation. However, running the SSGM based on the highest winter precipitation registered in the study area between 1801 and 2003 exhibits the possibility of very high snow-glide risk for most parts of the study area with significant increasing risk in the southern part. Given the very probable future climate during winter periods with increasing temperatures but uncertain development of precipitation patterns, snow-glide activity and linked glide avalanches might further increase at least in areas and altitudes with solid precipitation. In combination with the

  5. Stability and Degradation of Polymer Solar cells

    DEFF Research Database (Denmark)

    Norrman, Kion

    The current state-of-the-art allows for roll-to-roll manufacture of polymer solar cells in high volume with stability and efficiency sufficient to grant success in low-energy applications. However, further improvement is needed for the successful application of the devices in real life applications....... This is obtained by detailed knowledge of the degradation mechanisms. Methods to compare and standardize device stability are urgently needed. Methodologies to study failure mechanism that are based on physical processes (e.g. morphological changes) are well-established. However, methodologies to study chemical...

  6. Effect of bioaugmentation and supplementary carbon sources on degradation of polycyclic aromatic hydrocarbons by a soil-derived culture

    NARCIS (Netherlands)

    van Herwijnen, R.; Joffe, B.; Ryngaert, A.; Hausner, M.; Springael, D.; Govers, H.A.J.; Wuertz, S.; Parsons, J.R.

    2006-01-01

    Abstract The degradation of polycyclic aromatic hydrocarbons (PAHs) by an undefined culture obtained from a PAH-polluted soil and the same culture bioaugmented with three PAH-degrading strains was studied in carbon-limited chemostat cultures. The PAHs were degraded efficiently by the soil culture

  7. On-site and laboratory evaluations of soundscape quality in recreational urban spaces

    DEFF Research Database (Denmark)

    Bjerre, Lærke Cecilie; Larsen, Thea Mathilde; Sørensen, Anna Josefine

    2017-01-01

    Regulations for quiet urban areas are typically based on sound level limits alone. However, the nonacoustic context may be crucial for subjective soundscape quality. Aims: This study aimed at comparing the role of sound level and nonacoustic context for subjective urban soundscape assessment...... in the presence of the full on-site context, the visual context only, and without context. Materials and Methods: Soundscape quality was evaluated for three recreational urban spaces by using four subjective attributes: loudness, acceptance, stressfulness, and comfort. The sound level was measured at each site......, the availability of the visual context in the listening experiment had no significant effect on the ratings. The participants were overall more positive toward natural sound sources on site. Conclusion: The full immersion in the on-site nonacoustic context may be important when evaluating overall soundscape...

  8. Humic Acid Degradation by ZnO Photocatalyst

    Directory of Open Access Journals (Sweden)

    Sekartaji Putri A.

    2016-01-01

    Full Text Available Humic acid (HA is universally present in soils and natural water resources in a yellow-brown form. HA can react with chlorine during drinking water treatment and produce disinfection byproducts (DBPs, such as trihalomethanes (THMs and haloacetic acids (HAAs, which are harmful for health. Therefore, HA has to be eliminated from water environment. The photocatalysis is an effective alternative solution for the degradation of HA in a water environment. This research aims to degrade HA from water environment. The rapid degradation of HA, using zinc oxide nanoparticles, irradiated by ultraviolet light (ZnO/UV, is investigated. The optimum conditions of pertinent factors, which include the light wavelength (UV-A and UV-C, and light intensity, HA concentration, ZnO dose, and contact time are investigated at neutral pH conditions, considered for drinking water treatment. HA degradation efficiency reached more than 80% after 60 min for both types of irradiation in optimum conditions of 0.3 g/L ZnO dose in 180 min of contact time. Comparisons for degradation efficiency under UV-A and UV-C irradiation indicate that UV-C has higher efficiency, up to 150 min of contact time. The reusability of catalyst is performed for three reuses and still revealed effective for beneficial commercial applications.

  9. Petroleum pollutant degradation by surface water microorganisms.

    Science.gov (United States)

    Antić, Malisa P; Jovancićević, Branimir S; Ilić, Mila; Vrvić, Miroslav M; Schwarzbauer, Jan

    2006-09-01

    It is well known that the composition of petroleum or some of its processing products changes in the environment mostly under the influence of microorganisms. A series of experiments was conducted in order to define the optimum conditions for an efficient biodegradation of petroleum pollutant, or bioremediation of different segments of the environment. The aim of these investigations was to show to what extent the hydrocarbons of a petroleum pollutant are degraded by microbial cultures which were isolated as dominant microorganisms from a surface water of a wastewater canal of an oil refinery and a nitrogen plant. Biodegradation experiments were conducted on one paraffinic, and one naphthenic type of petroleum during a three month period under aerobic conditions, varying the following parameters: Inorganic (Kp) or an organic medium (Bh) with or without exposition to light. Microorganisms were analyzed in a surface water sample from a canal (Pancevo, Serbia), into which wastewater from an oil refinery and a nitrogen plant is released. The consortia of microorganisms were isolated from the water sample (most abundant species: Phormidium foveolarum--filamentous Cyanobacteria, blue-green algae and Achanthes minutissima, diatoms, algae). The simulation experiments of biodegradation were conducted with the biomass suspension and crude oils Sirakovo (Sir, paraffinic type) and Velebit (Ve, naphthenic type). After a three month period, organic substance was extracted by means of chloroform. In the extracts, the content of saturated hydrocarbons, aromatic hydrocarbons, alcohols and fatty acids was determined (the group composition). n-Alkanes and isoprenoid aliphatic alkanes, pristane and phytane, in the aliphatic fractions, were analyzed using gas chromatography (GC). Total isoprenoid aliphatic alkanes and polycyclic alkanes of sterane and triterpane types were analyzed by GC-MS. Paraffinic type petroleums have a significant loss of saturated hydrocarbons. For naphthenic

  10. On-Site Inspection RadioIsotopic Spectroscopy (Osiris) System Development

    Energy Technology Data Exchange (ETDEWEB)

    Caffrey, Gus J. [Idaho National Laboratory, Idaho Falls, ID (United States); Egger, Ann E. [Idaho National Laboratory, Idaho Falls, ID (United States); Krebs, Kenneth M. [Idaho National Laboratory, Idaho Falls, ID (United States); Milbrath, B. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jordan, D. V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Warren, G. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wilmer, N. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-09-01

    We have designed and tested hardware and software for the acquisition and analysis of high-resolution gamma-ray spectra during on-site inspections under the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The On-Site Inspection RadioIsotopic Spectroscopy—Osiris—software filters the spectral data to display only radioisotopic information relevant to CTBT on-site inspections, e.g.,132I. A set of over 100 fission-product spectra was employed for Osiris testing. These spectra were measured, where possible, or generated by modeling. The synthetic test spectral compositions include non-nuclear-explosion scenarios, e.g., a severe nuclear reactor accident, and nuclear-explosion scenarios such as a vented underground nuclear test. Comparing its computer-based analyses to expert visual analyses of the test spectra, Osiris correctly identifies CTBT-relevant fission product isotopes at the 95% level or better.The Osiris gamma-ray spectrometer is a mechanically-cooled, battery-powered ORTEC Transpec-100, chosen to avoid the need for liquid nitrogen during on-site inspections. The spectrometer was used successfully during the recent 2014 CTBT Integrated Field Exercise in Jordan. The spectrometer is controlled and the spectral data analyzed by a Panasonic Toughbook notebook computer. To date, software development has been the main focus of the Osiris project. In FY2016-17, we plan to modify the Osiris hardware, integrate the Osiris software and hardware, and conduct rigorous field tests to ensure that the Osiris system will function correctly during CTBT on-site inspections. The planned development will raise Osiris to technology readiness level TRL-8; transfer the Osiris technology to a commercial manufacturer, and demonstrate Osiris to potential CTBT on-site inspectors.

  11. 75 FR 11921 - Heritage Aviation, Ltd., Including On-Site Leased Workers From Global Technical Services and...

    Science.gov (United States)

    2010-03-12

    ... Employment and Training Administration Heritage Aviation, Ltd., Including On-Site Leased Workers From Global... workers of Heritage Aviation, including on-site leased workers from Heritage Aviation, Ltd, including on... leased from Global Inc., were employed on-site at the Grand Prairie, Texas location of Heritage Aviation...

  12. 75 FR 453 - FLSMidth, Inc., Cement Division, Product Engineering, Including On-Site Leased Workers of Aerotek...

    Science.gov (United States)

    2010-01-05

    ...., Cement Division, Product Engineering, Including On-Site Leased Workers of Aerotek Contract Engineering..., applicable to workers of FLSmidth, Inc., Cement Division, Product Engineering, including on-site leased...-site leased workers from Clarke Consulting, Inc. were also employed on-site at FLSmidth, Inc., Cement...

  13. 78 FR 52974 - Gamesa Technology Corporation, Including On-Site Leased Workers From A & A Wind Pros Inc., ABB...

    Science.gov (United States)

    2013-08-27

    ..., Fairless Hills, Pennsylvania; Gamesa Technology Corporation, Including On-Site Leased Workers From Work..., Pennsylvania (TA-W-82,288A), Gamesa Technology Corporation, including on-site leased workers from Work Link... Employment and Training Administration Gamesa Technology Corporation, Including On-Site Leased Workers From A...

  14. 77 FR 31643 - Siltronic Corporation FAB1 Plant Including On-Site Leased Workers From Express Temporaries...

    Science.gov (United States)

    2012-05-29

    ... Employment and Training Administration Siltronic Corporation FAB1 Plant Including On-Site Leased Workers From... Corporation, Fab1 Plant, including on-site leased workers from Express Temporaries and Aerotek Commercial... workers leased from the afore-mentioned agencies who work(ed) on-site at subject firm. The amended notice...

  15. 77 FR 21588 - Hart and Cooley, Inc., A Subsidiary of Tomkins, PLC Including On-Site Leased Workers from...

    Science.gov (United States)

    2012-04-10

    ... Employment and Training Administration Hart and Cooley, Inc., A Subsidiary of Tomkins, PLC Including On- Site... subsidiary of Tomkins, PLC, including on-site leased workers from Reliable, Masiello Employment Services... workers from Hart and Cooley, Inc., a subsidiary of Tomkins, PLC, including on-site leased workers from...

  16. Training courses on neutron detection systems on the ISIS research reactor: on-site and through internet training

    Energy Technology Data Exchange (ETDEWEB)

    Lescop, B.; Badeau, G.; Ivanovic, S.; Foulon, F. [National Institute for Nuclear science and Technology French Atomic Energy and Alternative Energies Commission (CEA), Saclay Research Center, 91191 Gif-sur-Yvette (France)

    2015-07-01

    Today, ISIS research reactor is an essential tool for Education and Training programs organized by the National Institute for Nuclear Science and Technology (INSTN) from CEA. In the field of nuclear instrumentation, the INSTN offers both, theoretical courses and training courses on the use of neutron detection systems taking advantage of the ISIS research reactor for the supply of a wide range of neutron fluxes. This paper describes the content of the training carried out on the use of neutron detectors and detection systems, on-site or remote. The ISIS reactor is a 700 kW open core pool type reactor. The facility is very flexible since neutron detectors can be inserted into the core or its vicinity, and be used at different levels of power according to the needs of the course. Neutron fluxes, typically ranging from 1 to 10{sup 12} n/cm{sup 2}.s, can be obtained for the characterisation of the neutron detectors and detection systems. For the monitoring of the neutron density at low level of power, the Instrumentation and Control (I and C) system of the reactor is equipped with two detection systems, named BN1 and BN2. Each way contains a fission chamber, type CFUL01, connected to an electronic system type SIREX.The system works in pulse mode and exhibits two outputs: the counting rate and the doubling time. For the high level of power, the I and C is equipped with two detection systems HN1 and HN2.Each way contain a boron ionization chamber (type CC52) connected to an electronics system type SIREX. The system works in current mode and has two outputs: the current and the doubling time. For each mode, the trainees can observe and measure the signal at the different stages of the electronic system, with an oscilloscope. They can understand the role of each component of the detection system: detector, cable and each electronic block. The limitation of the detection modes and their operating range can be established from the measured signal. The trainees can also

  17. Degradation of juglone by Pleurotus sajor-caju.

    Science.gov (United States)

    Curreli, Nicoletta; Rescigno, Antonio; Rinaldi, Augusto; Pisu, Brunella; Sollai, Francesca; Sanjust, Enrico

    2004-08-01

    The toxic naphthoquinone juglone (5-hydroxy-1,4-naphthoquinone) is efficiently degraded by the ligninolytic fungus Pleurotus sajor-caju, as demonstrated by the total bleaching within 9 d of a conventional liquid culture medium supplemented with 0.6 mM juglone. The oxidative degradation involves the production of hydrogen peroxide arising from both enzymic and non-enzymic oxidation reactions, promoted by the fungus. Juglone is not directly attacked by the oxidative enzymes of the ligninolytic machinery of P. sajor-caju, such as laccase, manganese peroxidase and arylalcohol oxidase. On the other hand, this naphthoquinone is a good substrate for a reductase, which triggers an auto-oxidative process producing reactive oxygen species and leading to juglone degradation. The degradation process continues to completion by means of a direct, presumably non-catalysed reaction with hydrogen peroxide.

  18. Anaerobic degradation of benzoate by sulfate-reducing bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Silva, S.P.; Adorno, M.A.T.; Moraes, E.M.; Varesche, M.B.A. [Sao Paulo Univ., Sao Carlos, SP (Brazil). Biological Processes Laboratory

    2004-07-01

    Anaerobic processes are an efficient way to degrade aromatic compounds in industrial wastewater, such as phenol, cresol and benzoate. This study characterized the bacteria that degrades benzoate, an anaerobic degradation intermediate of several complex aromatic compounds. In particular, the study assessed the capacity to use benzoate with sulfate reducing bacteria in mesophilic conditions. Biofilm from polyurethane foam matrices of a fixed bed reactor was used as the cellular inoculum to treat industrial wastewater containing organic peroxide. Dilution techniques were used to purify the material and obtain cultures of cocci. The benzoate consumption capacity in sulfidogenic conditions was observed when the purified inoculum was applied to batch reactors with different benzoate/sulfate relations. Results indicate that purification was positive to bacteria that can degrade aromatic compounds. Desulfococcus multivorans bacteria was identified following the physiologic and kinetic experiments. The 0.6 benzoate/sulfate relation was considered ideal for complete consumption of carbon and total use of sulfur. 10 refs., 3 figs.

  19. Mapping the polysaccharide degradation potential of Aspergillus niger

    DEFF Research Database (Denmark)

    Andersen, Mikael Rørdam; Giese, Malene; de Vries, Ronald P.

    2012-01-01

    Background: The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required...... of a given fungus for polysaccharide degradation. Results: Through the compilation of information from 203 articles, we have systematized knowledge on the structure and degradation of 16 major types of plant polysaccharides to form a graphical overview. As a case example, we have combined this with a list...... of 188 genes coding for carbohydrate-active enzymes from Aspergillus niger, thus forming an analysis framework, which can be queried. Combination of this information network with gene expression analysis on mono-and polysaccharide substrates has allowed elucidation of concerted gene expression from...

  20. Degradation of 17α-methyltestosterone by hydroxyapatite catalyst

    Directory of Open Access Journals (Sweden)

    Daniela Langaro Savaris

    2018-02-01

    Full Text Available Fish farming is becoming a highly profitable economic activity and the rearing of fingerlings involves the practice of sex reversal for the production of species (male using the hormone 17α-methyltestosterone (MT. This study analyzed the methodology for degradation of the hormone through solar and ultraviolet radiation using hydroxyapatite (HAP as heterogeneous catalyst, synthesized by two different methods, with and without doping with nickel and copper. The results showed that MT hormone is degraded by ultraviolet or solar radiation, and accelerated in the presence of the HAP catalyst. In the presence of Fe (III in the medium, the degradation rate of the hormone decreases. The method of HAP synthesis influences the degradation efficiency.

  1. Degradation of phenol under combined irradiation of microwaves and ultrasound.

    Science.gov (United States)

    Wu, Zhi-Lin; Ondruschka, Bernd; Cravotto, Giancarlo

    2008-11-01

    A novel combined system of irradiation by microwaves and ultrasound is used to efficiently destroy phenol in aqueous solutions via sono-generated hydroxyl radicals and H2O2, in conjunction with the rapid thermal effect of microwaves on polar chemicals. Microwave irradiation enhances the sono-degradation of phenol without any additional catalyst although the effect is more marked when H2O2 is added. The degradation of phenol by MW or US alone or by combined irradiation of MW-US follows zero order kinetics. Degradation rate constants and yields of the main intermediates, catechol and hydroquinone, follow the order of MW-US > MW > US. The degradation rate also increases with higher reaction temperature in the MW reactor. The synergistic effects of MW and US were observed at 93 degrees C without addition of H2O2 and at 60 degrees C with addition of H2O2.

  2. Decoupling degradation in exciton formation and recombination during lifetime testing of organic light-emitting devices

    Science.gov (United States)

    Hershey, Kyle W.; Suddard-Bangsund, John; Qian, Gang; Holmes, Russell J.

    2017-09-01

    The analysis of organic light-emitting device degradation is typically restricted to fitting the overall luminance loss as a function of time or the characterization of fully degraded devices. To develop a more complete understanding of degradation, additional specific data are needed as a function of luminance loss. The overall degradation in luminance during testing can be decoupled into a loss in emitter photoluminescence efficiency and a reduction in the exciton formation efficiency. Here, we demonstrate a method that permits separation of these component efficiencies, yielding the time evolution of two additional specific device parameters that can be used in interpreting and modeling degradation without modification to the device architecture or introduction of any additional post-degradation characterization steps. Here, devices based on the phosphor tris[2-phenylpyridinato-C2,N]iridium(III) (Ir(ppy)3) are characterized as a function of initial luminance and emissive layer thickness. The overall loss in device luminance is found to originate primarily from a reduction in the exciton formation efficiency which is exacerbated in devices with thinner emissive layers. Interestingly, the contribution to overall degradation from a reduction in the efficiency of exciton recombination (i.e., photoluminescence) is unaffected by thickness, suggesting a fixed exciton recombination zone width and degradation at an interface.

  3. Degradation of copepod fecal pellets

    DEFF Research Database (Denmark)

    Poulsen, Louise K.; Iversen, Morten

    2008-01-01

    amount of fecal pellets. The total degradation rate of pellets by the natural plankton community of Oresund followed the phytoplankton biomass, with maximum degradation rate during the spring bloom (2.5 +/- 0.49 d(-1)) and minimum (0.52 +/- 0.14 d(-1)) during late winter. Total pellet removal rate ranged...

  4. Kinetics of alkali-based photocathode degradation

    Directory of Open Access Journals (Sweden)

    Vitaly Pavlenko

    2016-11-01

    Full Text Available We report on a kinetic model that describes the degradation of the quantum efficiency (QE of Cs3Sb and negative electron affinity (NEA GaAs photocathodes under UHV conditions. In addition to the generally accepted irreversible chemical change of a photocathode’s surface due to reactions with residual gases, such as O2, CO2, and H2O, the model incorporates an intermediate reversible physisorption step, similar to Langmuir adsorption. This intermediate step is needed to satisfactorily describe the strongly non-exponential QE degradation curves for two distinctly different classes of photocathodes –surface-activated and “bulk,” indicating that in both systems the QE degradation results from surface damage. The recovery of the QE upon improvement of vacuum conditions is also accurately predicted by this model with three parameters (rates of gas adsorption, desorption, and irreversible chemical reaction with the surface comprising metrics to better characterize the lifetime of the cathodes, instead of time-pressure exposure expressed in Langmuir units.

  5. Degradation of cyanotoxins (microcystin in drinking water using photoelectrooxidation

    Directory of Open Access Journals (Sweden)

    ACA Garcia

    Full Text Available The discharge of sewage and industrial effluents containing high concentrations of pollutants in water bodies increases eutrophication. Cyanobacteria, some of the organisms whose growth is promoted by high nutrient concentrations, are resistant and produce several types of toxins, known as cyanotoxins, highly harmful to human beings. Current water treatment systems for the public water supply are not efficient in degradation of toxins. Advanced oxidation processes (AOP have been tested for the removal of cyanotoxins, and the results have been positive. This study examines the application of photoelectrooxidation in the degradation of cyanotoxins (microcystins. The performance of the oxidative processes involved was evaluated separately: Photocatalysis, Electrolysis and Photoelectrooxidation. Results showed that the electrical current and UV radiation were directly associated with toxin degradation. The PEO system is efficient in removing cyanotoxins, and the reduction rate reached 99%. The final concentration of toxin was less than 1 µg/L of microcystin in the treated solution.

  6. Chemical effect of swirling jet-induced cavitation: degradation of rhodamine B in aqueous solution.

    Science.gov (United States)

    Wang, Xikui; Wang, Jingang; Guo, Peiquan; Guo, Weilin; Li, Guoliang

    2008-04-01

    The chemical effect of swirling jet-induced cavitation was investigated with the decomposing reaction of rhodamine B in aqueous solution. It was found that rhodamine B in aqueous solution can be degraded with swirling jet-induced cavitation and the degradation can be described by a pseudo-first-order kinetics. The effects of operating conditions such as pressure, temperature, initial concentration of rhodamine B, pH of water on the degradation rate of rhodamine B were discussed. It was found that the degradation rate of rhodamine B increased with increasing pressure and decreased with increasing initial concentration. It was also found that the degradation of rhodamine B was strongly dependent of temperature and pH of aqueous solution. The oxidation efficiency of swirling jet-induced cavitation for rhodamine B degradation was discussed and compared with ultrasonic cavitation. The result indicated that the swirling jet-induced cavitation is more energy efficient as compared to sonochemical cavitation.

  7. Proteogenomic Characterization of Monocyclic Aromatic Hydrocarbon Degradation Pathways in the Aniline-Degrading Bacterium Burkholderia sp. K24.

    Directory of Open Access Journals (Sweden)

    Sang-Yeop Lee

    Full Text Available Burkholderia sp. K24, formerly known as Acinetobacter lwoffii K24, is a soil bacterium capable of utilizing aniline as its sole carbon and nitrogen source. Genomic sequence analysis revealed that this bacterium possesses putative gene clusters for biodegradation of various monocyclic aromatic hydrocarbons (MAHs, including benzene, toluene, and xylene (BTX, as well as aniline. We verified the proposed MAH biodegradation pathways by dioxygenase activity assays, RT-PCR, and LC/MS-based quantitative proteomic analyses. This proteogenomic approach revealed four independent degradation pathways, all converging into the citric acid cycle. Aniline and p-hydroxybenzoate degradation pathways converged into the β-ketoadipate pathway. Benzoate and toluene were degraded through the benzoyl-CoA degradation pathway. The xylene isomers, i.e., o-, m-, and p-xylene, were degraded via the extradiol cleavage pathways. Salicylate was degraded through the gentisate degradation pathway. Our results show that Burkholderia sp. K24 possesses versatile biodegradation pathways, which may be employed for efficient bioremediation of aniline and BTX.

  8. Proteogenomic Characterization of Monocyclic Aromatic Hydrocarbon Degradation Pathways in the Aniline-Degrading Bacterium Burkholderia sp. K24.

    Science.gov (United States)

    Lee, Sang-Yeop; Kim, Gun-Hwa; Yun, Sung Ho; Choi, Chi-Won; Yi, Yoon-Sun; Kim, Jonghyun; Chung, Young-Ho; Park, Edmond Changkyun; Kim, Seung Il

    2016-01-01

    Burkholderia sp. K24, formerly known as Acinetobacter lwoffii K24, is a soil bacterium capable of utilizing aniline as its sole carbon and nitrogen source. Genomic sequence analysis revealed that this bacterium possesses putative gene clusters for biodegradation of various monocyclic aromatic hydrocarbons (MAHs), including benzene, toluene, and xylene (BTX), as well as aniline. We verified the proposed MAH biodegradation pathways by dioxygenase activity assays, RT-PCR, and LC/MS-based quantitative proteomic analyses. This proteogenomic approach revealed four independent degradation pathways, all converging into the citric acid cycle. Aniline and p-hydroxybenzoate degradation pathways converged into the β-ketoadipate pathway. Benzoate and toluene were degraded through the benzoyl-CoA degradation pathway. The xylene isomers, i.e., o-, m-, and p-xylene, were degraded via the extradiol cleavage pathways. Salicylate was degraded through the gentisate degradation pathway. Our results show that Burkholderia sp. K24 possesses versatile biodegradation pathways, which may be employed for efficient bioremediation of aniline and BTX.

  9. Evaluation of an on-site pilot static granular bed reactor (SGBR) for the treatment of slaughterhouse wastewater.

    Science.gov (United States)

    Park, Jaeyoung; Oh, Jin Hwan; Ellis, Timothy G

    2012-03-01

    An on-site pilot-scale static granular bed reactor (SGBR) system was evaluated for treating wastewater from a slaughterhouse in Iowa. The study evaluated SGBR reactor suitability for slaughterhose wastewater having high particulate COD concentration (7.9 ± 4.3 g COD/L) at 0.3-1.4 m(3)/m(2)/day of the surface loading rates. High organic removal efficiency (over 95% of TSS and VSS removal) was obtained due to the consistent treatability of SGBR system during operation at HRTs of 48, 36, 30, 24, and 20 h. The average effluent TSS, VSS, COD, soluble COD, and BOD(5) concentrations were 84, 71, 301,197, and 87 mg/L, respectively. An effective backwash procedure was performed once every 7-14 days to waste a portion of the accumulated solids in the system. This procedure limited the increase in hydraulic head loss and maintained the system stability. COD removal efficiencies greater than 95% were achieved at organic loading rates ranging from 0.77 to 12.76 kg/m(3)/day.

  10. In Situ/on-Site Biodegradation of Refined Oils and Fuels (A Technology Review). Volume 1.

    Science.gov (United States)

    1992-06-01

    zopfii can degrade hydrocarbons without light, while Scenedesmus strains can utilize n-heptadecane in the light only (Masters and Zajic, 1971). The...fertilizers consist of paraffinized urea and octyl phosphate and are selective- ly available to oil-degrading microorganisms only (Atlas and Bartha...H.M., Finnerty, D.W., and Bingeman, C.W. 1955. The fate of substituted urea herbicides in agricultural soils. Agron. J. 47:93-104. Hoag, G.E. and

  11. Isolation and Characterization of Hydrocarbon-Degrading Bacteria ...

    African Journals Online (AJOL)

    ADOWIE PERE

    work was aimed at isolating hydrocarbon degrading bacteria from three (3) mechanic workshop soils in. Benin City and to ascertain their ability to grow efficiently in hydrocarbon based medium. MATERIALS AND METHOD. The Study Site: Topsoil and subsoil samples were collected from auto-mechanic workshops at three.

  12. Isolation and Characterization of Hydrocarbon-Degrading Bacteria ...

    African Journals Online (AJOL)

    The bacterial species isolated were Bacillus spp., Pseudomonas spp., Staphylococcus spp. and Streptococcus spp. The isolates were also subjected to hydrocarbon degradation/utilization test where it was observed that Pseudomonas spp utilized the hydrocarbon in the medium more efficiently than the other isolates.

  13. Degradation of petroleum hydrocarbons by oil field isolated bacterial ...

    African Journals Online (AJOL)

    The aromatics (benzene, toluene and xylene) were vaporized in the 4th day of incubation, while the efficiency on polyaromatic fractions (anthracene, phenanthrene and pyrene) was 46.17 to 55.3% after 24 days. The ability of degrading long chain n-alkanes and crude oil at high concentrations makes the consortium ...

  14. Bioremediation and degradation of CCA-treated wood waste.

    Science.gov (United States)

    Barbara L Illman; Vina W. Yang

    2004-01-01

    Bioprocessing CCA wood waste is an efficient and economical alternative to depositing the waste in landfills, especially if landfill restrictions on CCA waste are imposed nation wide. We have developed bioremediation and degradation technologies for microbial processing of CCA waste. The technologies are based on specially formulated inoculum of wood decay fungi,...

  15. Drift Degradation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Dwayne C. Kicker

    2001-09-28

    A statistical description of the probable block sizes formed by fractures around the emplacement drifts has been developed for each of the lithologic units of the repository host horizon. A range of drift orientations with the drift azimuth varied in 15{sup o} increments has been considered in the static analysis. For the quasi-static seismic analysis, and the time-dependent and thermal effects analysis, two drift orientations have been considered: a drift azimuth of 105{sup o} and the current emplacement drift azimuth of 75{sup o}. The change in drift profile resulting from progressive deterioration of the emplacement drifts has been assessed both with and without backfill. Drift profiles have been determined for four different time increments, including static (i.e., upon excavation), 200 years, 2,000 years, and 10,000 years. The effect of seismic events on rock fall has been analyzed. Block size distributions and drift profiles have been determined for three seismic levels, including a 1,000-year event, a 5,000-year event, and a 10,000-year event. Data developed in this modeling and analysis activity have been entered into the TDMS (DTN: MO0109RDDAAMRR.003). The following conclusions have resulted from this drift degradation analysis: (1) The available fracture data are suitable for supporting a detailed key block analysis of the repository host horizon rock mass. The available data from the north-south Main Drift and the east-west Cross Drift provide a sufficient representative fracture sample of the repository emplacement drift horizon. However, the Tptpln fracture data are only available from a relatively small section of the Cross Drift, resulting in a smaller fracture sample size compared to the other lithologic units. This results in a lower degree of confidence that the key block data based on the Tptpln data set is actually representative of the overall Tptpln key block population. (2) The seismic effect on the rock fall size distribution for all events

  16. Performance of on-site Medical waste disinfection equipment in hospitals of Tabriz, Iran

    Directory of Open Access Journals (Sweden)

    Hassan Taghipour

    2016-10-01

    Full Text Available Background: The number of studies available on the performance of on-site medical waste treatment facilities is rare, to date. The aim of this study was to evaluate the performance of onsite medical waste treatment equipment in hospitals of Tabriz, Iran. Methods: A various range of the on-site medical waste disinfection equipment (autoclave, chemical disinfection, hydroclave, and dry thermal treatment was considered to select 10 out of 22 hospitals in Tabriz to be included in the survey. The apparatus were monitored mechanically, chemically, and biologically for a six months period in all of the selected hospitals. Results: The results of the chemical monitoring (Bowie-Dick tests indicated that 38.9% of the inspected autoclaves had operational problems in pre-vacuum, air leaks, inadequate steam penetration into the waste, and/or vacuum pump. The biological indicators revealed that about 55.55% of the samples were positive. The most of applied devices were not suitable for treating anatomical, pharmaceutical, cytotoxic, and chemical waste. Conclusion: Although on-site medical waste treating facilities have been installed in all the hospitals, the most of infectious-hazardous medical waste generated in the hospitals were deposited into a municipal solid waste landfill, without enough disinfection. The responsible authorities should stringently inspect and evaluate the operation of on-site medical waste treating equipment. An advanced off-site central facility with multi-treatment and disinfection equipment and enough capacity is recommended as an alternative.

  17. On-Site Renewable Energy and Green Buildings: A System-Level Analysis.

    Science.gov (United States)

    Al-Ghamdi, Sami G; Bilec, Melissa M

    2016-05-03

    Adopting a green building rating system (GBRSs) that strongly considers use of renewable energy can have important environmental consequences, particularly in developing countries. In this paper, we studied on-site renewable energy and GBRSs at the system level to explore potential benefits and challenges. While we have focused on GBRSs, the findings can offer additional insight for renewable incentives across sectors. An energy model was built for 25 sites to compute the potential solar and wind power production on-site and available within the building footprint and regional climate. A life-cycle approach and cost analysis were then completed to analyze the environmental and economic impacts. Environmental impacts of renewable energy varied dramatically between sites, in some cases, the environmental benefits were limited despite the significant economic burden of those renewable systems on-site and vice versa. Our recommendation for GBRSs, and broader policies and regulations, is to require buildings with higher environmental impacts to achieve higher levels of energy performance and on-site renewable energy utilization, instead of fixed percentages.

  18. 76 FR 5833 - Polaris Industries, Including On-Site Leased Workers From Westaff, Supply Technologies, Aerotek...

    Science.gov (United States)

    2011-02-02

    ... Employment and Training Administration Polaris Industries, Including On-Site Leased Workers From Westaff... Eligibility to Apply for Worker Adjustment Assistance on August 26, 2010, applicable to workers of Polaris... Polaris Industries. The Department has determined that these workers were sufficiently under the control...

  19. On-site energy consumption and selected emissions at softwood sawmills in the southwestern United States

    Science.gov (United States)

    Dan Loeffler; Nathaniel Anderson; Todd A. Morgan; Colin B. Sorenson

    2016-01-01

    Presently there is a lack of information describing US southwestern energy consumption and emissions generated from the sawmilling industry. This article uses a mail survey of softwood sawmills in the states of Arizona, Colorado, and New Mexico to develop a profile of on-site energy consumption and selected emissions for the industry. Energy consumption is...

  20. Enhanced On-Site Waste Management of Plasterboard in Construction Works: A Case Study in Spain

    Directory of Open Access Journals (Sweden)

    Ana Jiménez-Rivero

    2017-03-01

    Full Text Available On-site management of construction waste commonly determines its destination. In the case of plasterboard (PB, on-site segregation becomes crucial for closed-loop recycling. However, PB is commonly mixed with other wastes in Spain. In this context, the involvement of stakeholders that can contribute to reversing this current situation is needed. This paper analyzes on-site waste management of PB in Spain through a pilot study of a construction site, with the main objective of identifying best practices to increase waste prevention, waste minimization, and the recyclability of the waste. On-site visits and structured interviews were conducted. The results show five management stages: PB distribution (I; PB installation (II; Construction waste storage at the installation area (III; PB waste segregation at the installation area (IV and PB waste transfer to the PB container and storage (V. The proposed practices refer to each stage and include the merging of Stages III and IV. This measure would avoid the mixing of waste fractions in Stage III, maximizing the recyclability of PB. In addition, two requisites for achieving enhanced management are analyzed: ‘Training and commitment’ and ‘fulfilling the requirements established by the current regulation’. The results show that foremen adopted a more pessimistic attitude than installers towards a joint commitment for waste management. Moreover, not all supervisors valued the importance of a site waste management plan, regulated by the Royal Decree 105/2008 in Spain.

  1. Test methods for on site measurement of resistivity of concrete. A RILEM TC-154 Technical Recommendation

    NARCIS (Netherlands)

    Polder, R.B.

    2000-01-01

    This paper describes methods to assess concrete resistivity on site for various purposes related to corrosion and protection of reinforcement. It is based on a first draft of a RILEM Technical Recommendation. The electrical resistivity of concrete can be related to the two processes involved in

  2. Cost-effective on-site screening for anaemia in pregnancy in primary ...

    African Journals Online (AJOL)

    Objective. To determine the feasibility, accuracy and cost of developing a system of on-site screening for anaemia in pregnancy in primary care clinics. Setting. Mobile clinic team in Hlabisa health district, Kwazulu-Natal. Methods. Four hundred and forty-nine consecutive women attending antenatal clinics were screened for ...

  3. The On-Site Mentor of Counseling Interns: Perceptions of Ideal Role and Actual Role Performance

    Science.gov (United States)

    Lazovsky, Rivka; Shimoni, Aviva

    2007-01-01

    This study examined the role of the ideal on-site mentor and the actual mentor's role performance, as perceived by 158 mentor counselors and 171 school counseling interns. Results indicated that the ideal mentor's professional traits were given priority by both groups and that the teacher role was the most salient among role domains. In the actual…

  4. Technology development for phosphoric acid fuel cell powerplant (phase 2). [on site integrated energy systems

    Science.gov (United States)

    Christner, L.

    1980-01-01

    Progress is reported in the development of material, cell components, and reformers for on site integrated energy systems. Internal resistance and contact resistance were improved. Dissolved gases (O2, N2, and CO2) were found to have no effect on the electrochemical corrosion of phenolic composites. Stack performance was increased by 100 mV over the average 1979 level.

  5. Cost-effective on-site screening for anaemia in pregnancy in primary ...

    African Journals Online (AJOL)

    cost-savings, which are considerable, the opportunity costs of switching to on-site screening are noteworthy. Testing antenatal specimens in this district requires several hours of laboratory time each week :- time that could probably be more usefully spent on other tasks. Antenatal clinics in KwaZulu-Natal currently screen for.

  6. Design review package for the on-site monitor for solar heating and cooling systems

    Science.gov (United States)

    1977-01-01

    The performance specification and verification matrix for the on-site monitor (OSM) is presented. The OSM is a portable device which, when connected to the Site Data Acquisition subsystem, allows readout of data on solar heating and cooling operational test sites.

  7. A rapid assay for on-site monitoring of infliximab trough levels: a feasibility study

    NARCIS (Netherlands)

    Corstjens, Paul L. A. M.; Fidder, Herma H.; Wiesmeijer, Karien C.; de Dood, Claudia J.; Rispens, Theo; Wolbink, Gert-Jan; Hommes, Daniel W.; Tanke, Hans J.

    2013-01-01

    Monitoring levels of biologicals against tumor necrosis factor (TNF) has been suggested to improve therapeutic outcomes in inflammatory bowel diseases (IBDs). This pilot study describes a rapid lateral flow (LF)-based assay for on-site monitoring of serum trough levels of humanized monoclonal

  8. On-site screening for maternal syphilis in an antenatal clinic

    African Journals Online (AJOL)

    Abstract Study objective. To determine the sensitivity, specificity, negative predictive value and positive predictive value of the rapid plasma reagin (RPR) test as performed on site in an antenatal clinic to facilitate immediate diagnosis and treatment of maternal syphilis. Design. Open, descriptive study. Setting. Antenatal ...

  9. On-site screening for syphilis at an antenatal clinic | Delport | South ...

    African Journals Online (AJOL)

    Objective. To determine the validity, predictive value and accuracy of the rapid plasma reagin card test performed on site to diagnose active syphilis in pregnant women so that immediate treatment can be offered to prevent congenital syphilis. Design. Open, descriptive study. Setting. Antenatal clinic, Mamelodi Hospital, ...

  10. On-site screening for maternal syphilis in an antenatal clinic ...

    African Journals Online (AJOL)

    Study objective. To determine the sensitivity, specificity, negative predictive value and positive predictive value of the rapid plasma reagin (RPR) test as performed on site in an antenatal clinic to facilitate immediate diagnosis and treatment of maternal syphilis. Design. Open, descriptive study. Setting. Antenatal clinic ...

  11. 75 FR 66796 - Multina, USA, Including On-Site Leased Workers From Westaff, Plattsburgh, NY; Amended...

    Science.gov (United States)

    2010-10-29

    ... Employment and Training Administration Multina, USA, Including On-Site Leased Workers From Westaff... accordance with section 223 of the Trade Act of 1974, as amended (``Act''), 19 U.S.C. 2273, the Department of..., applicable to workers of Multina, USA, Plattsburgh, New York. The notice was published in the Federal...

  12. On-Site Effects and Cost of Fertility Erosion from Five Small ...

    African Journals Online (AJOL)

    A study was carried out in the Upper East Region of Ghana to assess the on-site effects and the cost of fertility erosion from five small reservoir catchments (Dua, Doba, Zebilla, Kumpalgogo and Bugri). The catchment soils and reservoir sediments were sampled and analyzed for their bulk density and nutrient content.

  13. 13 CFR 120.1050 - On-site reviews and examinations.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false On-site reviews and examinations. 120.1050 Section 120.1050 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS...: (1) Capital adequacy; (2) Asset quality (including credit administration and allowance for loan...

  14. 75 FR 71464 - Metlife Technology, Operations, and Information Technology Groups Including On-Site Leased...

    Science.gov (United States)

    2010-11-23

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Metlife Technology, Operations, and Information Technology Groups Including On-Site Leased Workers From Adecco, Cognizant, IBM, Infosys, Kana, Patni, Siemens, Tapfin, Veritas Moosic, PA, Metlife Technology, Operations,...

  15. Rapid on-site evaluation of axillary fine-needle aspiration cytology in breast cancer.

    LENUS (Irish Health Repository)

    O'Leary, D P

    2012-06-01

    Axillary ultrasonography (AUS) and fine-needle aspiration cytology (FNAC) can establish axillary lymph node status before surgery, although this technique is hampered by poor adequacy rates. To achieve consistently high rates of FNAC adequacy, rapid on-site evaluation (ROSE) of FNAC samples was introduced.

  16. Solitary heat waves in nonlinear lattices with squared on-site potential

    Indian Academy of Sciences (India)

    A model Hamiltonian is proposed for heat conduction in a nonlinear lattice with squared on-site potential using the second quantized operators and averaging the same using a suitable wave function, equations are derived in discrete form for the field amplitude and the properties of heat transfer are examined theoretically.

  17. Limitations of on-site dairy farm regulatory debits as milk quality predictors.

    Science.gov (United States)

    Borneman, Darand L; Stiegert, Kyle; Ingham, Steve

    2015-03-01

    In the United States, compliance with grade A raw fluid milk regulatory standards is assessed via laboratory milk quality testing and by on-site inspection of producers (farms). This study evaluated the correlation between on-site survey debits being marked and somatic cell count (SCC) or standard plate count (SPC) laboratory results for 1,301 Wisconsin grade A dairy farms in 2012. Debits recorded on the survey form were tested as predictors of laboratory results utilizing ordinary least squares regression to determine if results of the current method for on-site evaluation of grade A dairy farms accurately predict SCC and SPC test results. Such a correlation may indicate that current methods of on-site inspection serve the primary intended purpose of assuring availability of high-quality milk. A model for predicting SCC was estimated using ordinary least squares regression methods. Step-wise selected regressors of grouped debit items were able to predict SCC levels with some degree of accuracy (adjusted R2=0.1432). Specific debit items, seasonality, and farm size were the best predictors of SCC levels. The SPC data presented an analytical challenge because over 75% of the SPC observations were at or below a 25,000 cfu/mL threshold but were recorded by testing laboratories as at the threshold value. This classic censoring problem necessitated the use of a Tobit regression approach. Even with this approach, prediction of SPC values based on on-site survey criteria was much less successful (adjusted R2=0.034) and provided little support for the on-site survey system as a way to inform farmers about making improvements that would improve SPC. The lower level of correlation with SPC may indicate that factors affecting SPC are more varied and differ from those affecting SCC. Further, unobserved deficiencies in postmilking handling and storage sanitation could enhance bacterial growth and increase SPC, whereas postmilking sanitation will have no effect on SCC because

  18. Anaerobic benzene degradation by bacteria

    Science.gov (United States)

    Vogt, Carsten; Kleinsteuber, Sabine; Richnow, Hans‐Hermann

    2011-01-01

    Summary Benzene is a widespread and toxic contaminant. The fate of benzene in contaminated aquifers seems to be primarily controlled by the abundance of oxygen: benzene is aerobically degraded at high rates by ubiquitous microorganisms, and the oxygen‐dependent pathways for its breakdown were elucidated more than 50 years ago. In contrast, benzene was thought to be persistent under anoxic conditions until 25 years ago. Nevertheless, within the last 15 years, several benzene‐degrading cultures have been enriched under varying electron acceptor conditions in laboratories around the world, and organisms involved in anaerobic benzene degradation have been identified, indicating that anaerobic benzene degradation is a relevant environmental process. However, only a few benzene degraders have been isolated in pure culture so far, and they all use nitrate as an electron acceptor. In some highly enriched strictly anaerobic cultures, benzene has been described to be mineralized cooperatively by two or more different organisms. Despite great efforts, the biochemical mechanism by which the aromatic ring of benzene is activated in the absence of oxygen is still not fully elucidated; methylation, hydroxylation and carboxylation are discussed as likely reactions. This review summarizes the current knowledge about the ‘key players’ of anaerobic benzene degradation under different electron acceptor conditions and the possible pathway(s) of anaerobic benzene degradation. PMID:21450012

  19. Performance Degradation of LSCF Cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Alinger, Matthew

    2013-09-30

    This final report summarizes the progress made during the October 1, 2008 - September 30, 2013 period under Cooperative Agreement DE-NT0004109 for the U. S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled “Performance Degradation of LSCF Cathodes”. The primary objective of this program is to develop a performance degradation mitigation path for high performing, cost-effective solid oxide fuel cells (SOFCs). Strategies to mitigate performance degradation are developed and implemented. In addition, thermal spray manufacturing of SOFCs is explored. Combined, this work establishes a basis for cost-effective SOFC cells.

  20. Bioremediation of hydrocarbon degradation in a petroleum-contaminated soil and microbial population and activity determination.

    Science.gov (United States)

    Wu, Manli; Li, Wei; Dick, Warren A; Ye, Xiqiong; Chen, Kaili; Kost, David; Chen, Liming

    2017-02-01

    Bioremediation of hydrocarbon degradation in petroleum-polluted soil is carried out by various microorganisms. However, little information is available for the relationships between hydrocarbon degradation rates in petroleum-contaminated soil and microbial population and activity in laboratory assay. In a microcosm study, degradation rate and efficiency of total petroleum hydrocarbons (TPH), alkanes, and polycyclic aromatic hydrocarbons (PAH) in a petroleum-contaminated soil were determined using an infrared photometer oil content analyzer and a gas chromatography mass spectrometry (GC-MS). Also, the populations of TPH, alkane, and PAH degraders were enumerated by a modified most probable number (MPN) procedure, and the hydrocarbon degrading activities of these degraders were determined by the Biolog (MT2) MicroPlates assay. Results showed linear correlations between the TPH and alkane degradation rates and the population and activity increases of TPH and alkane degraders, but no correlation was observed between the PAH degradation rates and the PAH population and activity increases. Petroleum hydrocarbon degrading microbial population measured by MPN was significantly correlated with metabolic activity in the Biolog assay. The results suggest that the MPN procedure and the Biolog assay are efficient methods for assessing the rates of TPH and alkane, but not PAH, bioremediation in oil-contaminated soil in laboratory. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Mapping and Imaging Methodologies within the Comprehensive Test Ban Treaty's On-Site Inspection Framework

    Science.gov (United States)

    Hawkins, W.; Sussman, A. J.; Kelley, R. E.; Wohletz, K. H.; Schultz-Fellenz, E. S.

    2013-12-01

    On-site inspection (OSI) is the final verification measure of the Comprehensive Nuclear Test Ban Treaty (CTBT). OSIs rely heavily on geologic and geophysical investigations. The objective is to apply methods that are effective, efficient and minimally intrusive. We present a general overview of the OSI as provisioned in the CTBT, specifying the allowed techniques and the timeline for their application. A CTBT OSI relies on many geological, geophysical and radiological methods. The search area for an OSI is mostly defined by uncertainty in the location of a suspect event detected by the International Monitoring System (IMS) and reported through the International Data Center and can be as large as 1000 km2. Thus OSI methods are fundamentally divided into general survey methods that narrow the search area and more focused, detailed survey methods to look for evidence of a potential underground explosion and try to find its location within an area of several km2. The purpose and goal of a CTBT OSI, as specified in the Article IV of the Treaty, is 'to clarify whether a nuclear explosion has been carried out in violation of the Treaty' and to 'gather any facts which might assist in identifying any possible violator.' Through the use of visual, geophysical, and radiological techniques, OSIs can detect and characterize anomalies and artifacts related to the event that triggered the inspection. In the context of an OSI, an 'observable' is a physical property that is important to recognize and document because of its relevance to the purpose of the inspection. Potential observables include: (1) visual observables such as ground/environmental disturbances and manmade features, (2) geophysical techniques that provide measurements of altered and damaged ground and buried artifacts, and (3) radiological measurements on samples. Information provided in this presentation comes from observations associated with historical testing activities that were not intended to go undetected

  2. Plant biomass degradation by fungi.

    Science.gov (United States)

    Mäkelä, Miia R; Donofrio, Nicole; de Vries, Ronald P

    2014-11-01

    Plant biomass degradation by fungi has implications for several fields of science. The enzyme systems employed by fungi for this are broadly used in various industrial sectors such as food & feed, pulp & paper, detergents, textile, wine, and more recently biofuels and biochemicals. In addition, the topic is highly relevant in the field of plant pathogenic fungi as they degrade plant biomass to either gain access to the plant or as carbon source, resulting in significant crop losses. Finally, fungi are the main degraders of plant biomass in nature and as such have an essential role in the global carbon cycle and ecology in general. In this review we provide a global view on the development of this research topic in saprobic ascomycetes and basidiomycetes and in plant pathogenic fungi and link this to the other papers of this special issue on plant biomass degradation by fungi. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. On-site removal of antibiotics and antibiotic resistance genes from leachate by aged refuse bioreactor: Effects of microbial community and operational parameters.

    Science.gov (United States)

    Su, Yinglong; Wang, Jiaxin; Huang, Zhiting; Xie, Bing

    2017-07-01

    The abuse of antibiotics has raised the prevalence of antibiotic resistance, which will pose potential risk to human health. Leachate, generated during the landfill treatment of municipal solid waste, is the important hotspot of the antibiotics and antibiotic resistance genes (ARGs), and no effective on-site treatment has been put forward for preventing ARGs dissemination. Herein, the aged refuse bioreactor was employed to remove antibiotics and ARGs from leachate, and the great removal performance was observed. For the detected antibiotics, the total removal efficiency was about 76.75%, and sulfanilamide and macrolide were removed with high efficiencies (>80%). Among the target ARGs, tetracycline and macrolide resistance genes (tetM, tetQ and ermB) were eliminated with 1.2-2.0 orders of magnitude. The occurrences of ARGs did not correlated with water quality parameters such as COD, total nitrogen, ammonia, nitrate and nitrite, but closely linked to the variations of the bacterial community structure. Redundancy analysis (RDA) indicated the significant correlations between four genera and the distribution of ARGs, which implied that these key genera (including potential pathogens) drove the ARGs removal. Furthermore, the hydraulic loading test confirmed that the aged refuse bioreactor was capable of achieving high removal efficiencies even under shock loading for the higher loading was negative for the proliferations of potential ARGs hosts. This study suggested that aged refuse bioreactor could be a promising way for antibiotics and ARGs on-site removal from leachate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. SIMULTANEOUS DEGRADATION OF SOME PHTHALATE ESTERS UNDER FENTON AND PHOTO-FENTON OXIDATION PROCESSES

    National Research Council Canada - National Science Library

    BELDEAN-GALEA M.S; COZMA A.M; DIODIU R

    2015-01-01

    In this study the assessment of the degradation efficiency of five phthalates, DEP, BBP, DEHP, DINP and DIDP, found in a mixture in a liquid phase, using the Fenton and Photo Fenton oxidation processes, was conducted...

  5. Some Misconceptions About Plastic Degradation

    OpenAIRE

    Raouf, Mohamed Imad N. Raouf

    1999-01-01

    In consistence with the importance of implementing best utilization of human resources towards maintaining suitable healthy environment for our next generations, concepts and fundamentals upon which most researches on degradation of plastics are based, as a solution of solid waste reduction, will be discussed. Proper understanding of plastic figures would better utilize human efforts toward useful tasks to control solid waste. Unfortunately, when plastics are made more degradable, they becom...

  6. Anaerobic Degradation of Phenolic Compounds

    OpenAIRE

    Schink, Bernhard; Philipp, Bodo; Jochen A Müller

    2000-01-01

    Mononuclear aromatic compounds are degraded anaerobically through three main pathways, the benzoyl-CoA pathway, the resorcinol pathway, and the phloroglucinol pathway. Various modification reactions channel a broad variety of mononuclear aromatics including aromatic hydrocarbons into either one of these three pathways. Recently, a further pathway was discovered with hydroxyhydroquinone as central intermediate through which especially nitrate-reducing bacteria degrade phenolic compounds and so...

  7. [Sodium peroxydisulfate activation by heat and Fe(II) for the degradation of 4-CP].

    Science.gov (United States)

    Zhao, Jin-ying; Zhang, Yao-bin; Quan, Xie; Zhao, Ya-zhi

    2010-05-01

    The heat and ferrous ion-activated sodium peroxydisulfate (PDS) for the oxidation of 4-chlorophenol (4-CP) was investigated. These processes are based on the generation of sulfate radicals, which are powerful oxidizing species found in nature. The effects of temperature, pH, the initial concentrations of Fe (II), PDS and citric acid on the degradation efficiencies of 4-CP were studied. The results show that the degradAtion efficiency of 4-CP is significantly enhanced as temperature increases. The degradation efficiencies of 4-CP are 2.5% and 43.5% within 4 h at 30 degrees C and 50 degrees C, respectively. Moreover, 4-CP is degraded completely at 60 degrees C. The degradation efficiency of 4-CP follows the order: pH 4.0 > pH 7.0 > pH 10.0. In the PDS/Fe (II) system, ferrous ion played an important role in generating sulfate radicals at ambient temperature. The optimum experimental condition is established and the addition of probe compounds proves the formation of sulfate radicals. Furthermore, the iron availability in the aqueous solution is manipulated with the optimum amount of citric acid, as a chelating agent. The degradation efficiency of 4-CP is 50.9% in the PDS/Fe (II)/citric acid system, which is superior to 43.5% at 50 degrees C under the same initial concentration of PDS.

  8. Juggling Efficiency

    DEFF Research Database (Denmark)

    Andersen, Rikke Sand; Vedsted, Peter

    2015-01-01

    on institutional logics, we illustrate how a logic of efficiency organise and give shape to healthcare seeking practices as they manifest in local clinical settings. Overall, patient concerns are reconfigured to fit the local clinical setting and healthcare professionals and patients are required to juggle...... efficiency in order to deal with uncertainties and meet more complex or unpredictable needs. Lastly, building on the empirical case of cancer diagnostics, we discuss the implications of the pervasiveness of the logic of efficiency in the clinical setting and argue that provision of medical care in today......'s primary care settings requires careful balancing of increasing demands of efficiency, greater complexity of biomedical knowledge and consideration for individual patient needs....

  9. Working session 1: Tubing degradation

    Energy Technology Data Exchange (ETDEWEB)

    Kharshafdjian, G. [Atomic Energy of Canada, Mississauga, Ontario (Canada); Turluer, G. [IPSN, Fontenay-aux-Roses (France)

    1997-02-01

    A general introductory overview of the purpose of the group and the general subject area of SG tubing degradation was given by the facilitator. The purpose of the session was described as to {open_quotes}develop conclusions and proposals on regulatory and technical needs required to deal with the issues of SG tubing degradation.{close_quotes} Types, locations and characteristics of tubing degradation in steam generators were briefly reviewed. The well-known synergistic effects of materials, environment, and stress and strain/strain rate, subsequently referred to by the acronym {open_quotes}MESS{close_quotes} by some of the group members, were noted. The element of time (i.e., evolution of these variables with time) was emphasized. It was also suggested that the group might want to consider the related topics of inspection capabilities, operational variables, degradation remedies, and validity of test data, and some background information in these areas was provided. The presentation given by Peter Millet during the Plenary Session was reviewed; Specifically, the chemical aspects and the degradation from the secondary side of the steam generator were noted. The main issues discussed during the October 1995 EPRI meeting on secondary side corrosion were reported, and a listing of the potential SG tube degradations was provided and discussed.

  10. Mapping the polysaccharide degradation potential of Aspergillus niger

    Science.gov (United States)

    2012-01-01

    Background The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required. For each type of hemicellulose, a complex mixture of enzymes is required for complete conversion to fermentable monosaccharides. In plant-biomass degrading fungi, these enzymes are regulated and released by complex regulatory structures. In this study, we present a methodology for evaluating the potential of a given fungus for polysaccharide degradation. Results Through the compilation of information from 203 articles, we have systematized knowledge on the structure and degradation of 16 major types of plant polysaccharides to form a graphical overview. As a case example, we have combined this with a list of 188 genes coding for carbohydrate-active enzymes from Aspergillus niger, thus forming an analysis framework, which can be queried. Combination of this information network with gene expression analysis on mono- and polysaccharide substrates has allowed elucidation of concerted gene expression from this organism. One such example is the identification of a full set of extracellular polysaccharide-acting genes for the degradation of oat spelt xylan. Conclusions The mapping of plant polysaccharide structures along with the corresponding enzymatic activities is a powerful framework for expression analysis of carbohydrate-active enzymes. Applying this network-based approach, we provide the first genome-scale characterization of all genes coding for carbohydrate-active enzymes identified in A. niger. PMID:22799883

  11. Radiolytic degradation of malathion and lindane in aqueous solutions

    Science.gov (United States)

    Mohamed, K. A.; Basfar, A. A.; Al-Kahtani, H. A.; Al-Hamad, K. S.

    2009-11-01

    Degradation of malathion and lindane pesticides present in an aqueous solution was investigated on a laboratory scale upon gamma-irradiation from a 60Co source. The effects of pesticide group, presence of various additives and absorbed dose on efficiency of pesticide degradation were investigated. Gamma-irradiation was carried out in distilled water solutions (malathion and lindane) and in combination with humic solution (HS), nitrous oxide (N 2O) and HS/N 2O (lindane) over the range 0.1-2 kGy (malathion) and 5-30 kGy (lindane). Malathion was easily degraded at low absorbed doses compared to lindane in distilled water solutions. Absorbed doses required to remove 50% and 90% of initial malathion and lindane concentrations in distilled water solutions were 0.53 and 1.77 kGy (malathion) and 17.97 and 28.79 kGy (lindane), respectively. The presence of HS, N 2O and HS/N 2O additives in aqueous solutions, significantly improved the effectiveness of radiolytic degradation of lindane. Chemical analysis of the pesticides and the by-products resulted from the radiolytic degradation were made using a gas chromatography associated with mass spectrometry (GC-MS). Additionally, the final degradation products of irradiation as detected by ion chromatography (IC) were acetic acid and traces of some anions (phosphate and chloride).

  12. A General Accelerated Degradation Model Based on the Wiener Process

    Directory of Open Access Journals (Sweden)

    Le Liu

    2016-12-01

    Full Text Available Accelerated degradation testing (ADT is an efficient tool to conduct material service reliability and safety evaluations by analyzing performance degradation data. Traditional stochastic process models are mainly for linear or linearization degradation paths. However, those methods are not applicable for the situations where the degradation processes cannot be linearized. Hence, in this paper, a general ADT model based on the Wiener process is proposed to solve the problem for accelerated degradation data analysis. The general model can consider the unit-to-unit variation and temporal variation of the degradation process, and is suitable for both linear and nonlinear ADT analyses with single or multiple acceleration variables. The statistical inference is given to estimate the unknown parameters in both constant stress and step stress ADT. The simulation example and two real applications demonstrate that the proposed method can yield reliable lifetime evaluation results compared with the existing linear and time-scale transformation Wiener processes in both linear and nonlinear ADT analyses.

  13. Field sampling and selecting on-site analytical methods for explosives in soil

    Energy Technology Data Exchange (ETDEWEB)

    Crockett, A.B.; Craig, H.D.; Jenkins, T.F.; Sisk, W.E.

    1996-12-01

    A large number of defense-related sites are contaminated with elevated levels of secondary explosives. Levels of contamination range from barely detectable to levels above 10% that need special handling because of the detonation potential. Characterization of explosives-contaminated sites is particularly difficult because of the very heterogeneous distribution of contamination in the environment and within samples. To improve site characterization, several options exist including collecting more samples, providing on-site analytical data to help direct the investigation, compositing samples, improving homogenization of the samples, and extracting larger samples. This publication is intended to provide guidance to Remedial Project Managers regarding field sampling and on-site analytical methods for detecting and quantifying secondary explosive compounds in soils, and is not intended to include discussions of the safety issues associated with sites contaminated with explosive residues.

  14. Procurement Specifications Templates for On-Site Solar Photovoltaic: For Use in Developing Federal Solicitations

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-01-16

    With the increasing adaption of on-site renewable energy systems designed to feed site loads, there is a critical need to develop tools that allow the federal sector to become a mature and sophisticated consumer. This document is intended to reduce project development and operational risks while increasing the speed at which projects are completed; two necessary components to reach the scale required to meet mandates and achieve cost savings for taxpayers. This guide is intended to act as a living document where lessons learned from the increasing number of projects can be incorporated and provide guidance for efforts. While additional guides will be developed to cover other renewable technologies, this guide covers on-site solar photovoltaic systems with an emphasis on third-party designed, financed, owned, and operated systems.

  15. On-site treatment and landfilling of MSWI air pollution control residues

    DEFF Research Database (Denmark)

    Lundtorp, Kasper; Jensen, Dorthe Lærke; Sørensen, Mette Abildgaard

    2003-01-01

    Air pollution control (APC) residues from municipal solid waste incineration (MSWI) are difficult to landfill due to substantial leaching of trace metals. An on-site pretreatment prior to landfilling of APC-residues was investigated in terms of bench-scale experiments with a semidry APC-residue a......Air pollution control (APC) residues from municipal solid waste incineration (MSWI) are difficult to landfill due to substantial leaching of trace metals. An on-site pretreatment prior to landfilling of APC-residues was investigated in terms of bench-scale experiments with a semidry APC......-residue and a fly ash. The treatment involved mixing of the residues with a ferrous sulphate solution and subsequent oxidation of the suspension. Afterwards, the suspension was spread on a dedicated landfill section and allowed to drain by gravity through the drainage system of the landfill. The wastewater from...

  16. On-Site Surface Functionalization for Titanium Dental Implant with Nanotopography: Review and Outlook

    Directory of Open Access Journals (Sweden)

    Byung Gyu Kim

    2016-01-01

    Full Text Available Titanium (Ti has been the first choice of material for dental implant due to bonding ability to natural bone and great biocompatibility. Various types of surface roughness modification in nanoscale have been made as promising strategy for accelerating osseointegration of Ti dental implant. To have synergetic effect with nanotopography oriented favors in cell attachment, on-site surface functionalization with reproducibility of nanotopography is introduced as next strategy to further enhance cellular bioactivity. Extensive research has been conducted to investigate the potential of nanotopography preserved on-site surface functionalization for Ti dental implant. This review will discuss nonthermal atmospheric pressure plasma, ultraviolet, and low level of laser therapy on Ti dental implant with nanotopography as next generation of surface functionalization due to its abilities to induce superhydrophilicity or biofunctionality without change of nanotopography.

  17. Degradation mechanism of planar perovskite solar cells (Presentation Recording)

    Science.gov (United States)

    Qin, Chuanjiang; Matsushima, Toshinori; Adachi, Chihaya

    2015-10-01

    Organic-inorganic hybrid halide perovskites are an interesting class of materials that have excellent semiconductor properties, and demonstrated promising applications on many fields, such as solar cells, water photolysis, light emitting diodes, and amplified spontaneous emission. So far, the device lifetime is still short, and this is an important key issue faced for all researchers in this field.[1] The deep understanding of their durability and degradation mechanism is critical and necessary toward future applications. Towards development of efficient and long-term stable perovskite solar cells (PSCs), we firstly studied the relationship between crystallization, morphology, device architecture, efficiency and durability of encapsulated PSCs. Furthermore, the degradation mechanism of the devices was elucidated by different experimental methods. The well crystallized and fully covered perovskite layer improves not only power conversion efficiency but also long-time durability. Compared to a widely used silver counter electrode, lithium fluoride/aluminum and gold electrode-based PSCs demonstrated better durability owing to less chemical degradation and interface changing. We also confirmed that the amount of accumulated charge carriers induces the degradation of the PSCs, which was proved by a thermally stimulated current technique. Finally, we realized a planar PSC with excellent durability by improving device encapsulation and optimizing device structures. Reference: 1. M. Grätzel, Nature Materials 2014, 13, 838-842.

  18. Resolving Turbine Degradation

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Matthew [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kruizenga, Alan Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Withey, Elizabeth Ann [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-08-01

    The supercritical carbon dioxide (S-CO2) Brayton Cycle has gained significant attention in the last decade as an advanced power cycle capable of achieving high efficiency power conversion. Sandia National Laboratories, with support from the U.S. Department of Energy Office of Nuclear Energy (US DOE-NE), has been conducting research and development in order to deliver a technology that is ready for commercialization. Root cause analysis has been performed on the Recompression Loop at Sandia National Laboratories. It was found that particles throughout the loop are stainless steel, likely alloy 316 based upon the elemental composition. Deployment of a filter scheme is underway to both protect the turbomachinery and also for purposes of determining the specific cause for the particulate. Shake down tests of electric resistance (ER) as a potential in-situ monitoring scheme shows promise in high temperature systems. A modified instrument was purchased and held at 650°C for more than 1.5 months to date without issue. Quantitative measurements of this instrument will be benchmarked against witness samples in the future, but all qualitative trends to date are as to be expected. ER is a robust method for corrosion monitoring, but very slow at responding and can take several weeks under conditions to see obvious changes in behavior. Electrochemical noise was identified as an advanced technique that should be pursued for the ability to identify transients that would lead to poor material performance.

  19. Upflow evapotranspiration system for the treatment of on-site wastewater effluent

    OpenAIRE

    Sean Curneen; Laurence Gill

    2015-01-01

    Full-scale willow evapotranspiration systems fed from the base with septic tank or secondary treated domestic effluent from single houses have been constructed and instrumented in Ireland in order to investigate whether the technology could provide a solution to the problem of on-site effluent disposal in areas with low permeability subsoils. Continuous monitoring of rainfall, reference evapotranspiration, effluent flows and water level in the sealed systems revealed varying evapotranspiratio...

  20. Optimal selection of on-site generation with combined heat andpower applications

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, Afzal S.; Marnay, Chris; Bailey, Owen; HamachiLaCommare, Kristina

    2004-11-30

    While demand for electricity continues to grow, expansion of the traditional electricity supply system, or macrogrid, is constrained and is unlikely to keep pace with the growing thirst western economies have for electricity. Furthermore, no compelling case has been made that perpetual improvement in the overall power quality and reliability (PQR)delivered is technically possible or economically desirable. An alternative path to providing high PQR for sensitive loads would generate close to them in microgrids, such as the Consortium for Electricity Reliability Technology Solutions (CERTS) Microgrid. Distributed generation would alleviate the pressure for endless improvement in macrogrid PQR and might allow the establishment of a sounder economically based level of universal grid service. Energy conversion from available fuels to electricity close to loads can also provide combined heat and power (CHP) opportunities that can significantly improve the economics of small-scale on-site power generation, especially in hot climates when the waste heat serves absorption cycle cooling equipment that displaces expensive on-peak electricity. An optimization model, the Distributed Energy Resources Customer Adoption Model (DER-CAM), developed at Berkeley Lab identifies the energy bill minimizing combination of on-site generation and heat recovery equipment for sites, given their electricity and heat requirements, the tariffs they face, and a menu of available equipment. DER-CAM is used to conduct a systemic energy analysis of a southern California naval base building and demonstrates atypical current economic on-site power opportunity. Results achieve cost reductions of about 15 percent with DER, depending on the tariff.Furthermore, almost all of the energy is provided on-site, indicating that modest cost savings can be achieved when the microgrid is free to select distributed generation and heat recovery equipment in order to minimize its over all costs.

  1. Using Automated On-Site Monitoring to Calibrate Empirical Models of Trihalomethanes Concentrations in Drinking Water

    OpenAIRE

    Thomas E. Watts III; Robyn A. Snow; Brown, Aaron W.; J. C. York; Greg Fantom; Paul S. Simone Jr.; Emmert, Gary L.

    2015-01-01

    An automated, on-site trihalomethanes concentration data set from a conventional water treatment plant was used to optimize powdered activated carbon and pre-chlorination doses. The trihalomethanes concentration data set was used with commonly monitored water quality parameters to improve an empirical model of trihalomethanes formation. A calibrated model was used to predict trihalomethanes concentrations the following year. The agreement between the models and measurements was evaluated. The...

  2. Training of medical teams on-site for individual and coordinated response in emergency management

    DEFF Research Database (Denmark)

    Andersen, Verner

    2003-01-01

    A system for training of coordination and cooperation of decision makers in emergency management has been under construction for some time. A first prototype of the system was developed in the MUSTER system. The system is being developed modularly with one module for each of the suborganisations ...... system for specific training set-ups for specific groups of trainees. The first module completed as a commercial system, "Training of medical teams on site", will be presented....

  3. Degradation of bulk diffusion length in CZ silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Reiss, J.H.; King, R.R.; Mitchell, K.W. [Siemens Solar Industries, Camarillo, CA (United States)

    1995-08-01

    Commercially-produced, unencapsulated, CZ silicon solar cells can lose 3 to 4% of their initial efficiency after exposure to light. After this initial, rapid ( < 30 min.) decrease, the cell power output remains stable. The cell performance recovers in a matter of hours in the dark at room temperature, and degrades again under light exposure. The different conditions under which CZ silicon cells degrade, and the reverse process, annealing, are characterized with the methods of spectral response and current-voltage (I-V) measurements. Iron impurities are a possible cause of this effect.

  4. Transient electroluminescence on pristine and degraded phosphorescent blue OLEDs

    Science.gov (United States)

    Niu, Quan; Blom, Paul W. M.; May, Falk; Heimel, Paul; Zhang, Minlu; Eickhoff, Christian; Heinemeyer, Ute; Lennartz, Christian; Crǎciun, N. Irina

    2017-11-01

    In state-of-the-art blue phosphorescent organic light-emitting diode (PHOLED) device architectures, electrons and holes are injected into the emissive layer, where they are carried by the emitting and hole transporting units, respectively. Using transient electroluminescence measurements, we disentangle the contribution of the electrons and holes on the transport and efficiency of both pristine and degraded PHOLEDs. By varying the concentration of hole transporting units, we show that for pristine PHOLEDs, the transport is electron dominated. Furthermore, degradation of the PHOLEDs upon electrical aging is not related to the hole transport but is governed by a decrease in the electron transport due to the formation of electron traps.

  5. Redox regulation of insulin degradation by insulin-degrading enzyme.

    Directory of Open Access Journals (Sweden)

    Crystal M Cordes

    Full Text Available Insulin-degrading enzyme (IDE is a thiol sensitive peptidase that degrades insulin and amyloid β, and has been linked to type 2 diabetes mellitus and Alzheimer's disease. We examined the thiol sensitivity of IDE using S-nitrosoglutathione, reduced glutathione, and oxidized glutathione to distinguish the effects of nitric oxide from that of the redox state. The in vitro activity of IDE was studied using either partially purified cytosolic enzyme from male Sprague-Dawley rats, or purified rat recombinant enzyme. We confirm that nitric oxide inhibits the degrading activity of IDE, and that it affects proteasome activity through this interaction with IDE, but does not affect the proteasome directly. Oxidized glutathione inhibits IDE through glutathionylation, which was reversible by dithiothreitol but not by ascorbic acid. Reduced glutathione had no effect on IDE, but reacted with partially degraded insulin to disrupt its disulfide bonds and accelerate its breakdown to trichloroacetic acid soluble fragments. Our results demonstrate the sensitivity of insulin degradation by IDE to the redox environment and suggest another mechanism by which the cell's oxidation state may contribute to the development of, and the link between, type 2 diabetes and Alzheimer's disease.

  6. On-Site Chiropractic Care as an Employee Benefit: A Single-Location Case Study.

    Science.gov (United States)

    Minicozzi, Salvatore J; Russell, Brent S

    2017-09-01

    The purpose of this report is to describe the role of on-site chiropractic care in one corporate environment. A part-time chiropractic practice that provides services to a single company on site, 1 day per week, is described. Most care is oriented toward "wellness," is paid for by the employer, and is limited only by the chiropractor's few weekly hours of on-site availability. With approval from the company, the authors conducted an absenteeism analysis after obtaining ethics approval and consent from employee-patients who received care between 2012 and 2014. Comparisons of absenteeism rates of the sample were compared with lost worktime rates from the US Bureau of Labor Statistics' Labor Force Statistics. Of 40 current employees, 35 used chiropractic services; 17 employee-patients met the inclusion criteria. The lost worktime rates of those using chiropractic services (0.72%, 0.55%, and 0.67%, for 2012, 2013, and 2014, respectively) were lower than corresponding rates from Labor Force Statistics (1.5%, 1.2%, and 1.1%). Absenteeism for the employee-patients was lower than equivalent national figures in this sample of workers. Though these results may or may not be related to the chiropractic care, these findings prompt further investigation into this relationship.

  7. On-Site 3D Printing of Functional Custom Mallet Splints for Mars Analogue Crewmembers.

    Science.gov (United States)

    Wong, Julielynn Y

    2015-10-01

    The first off-Earth fused deposition modeling (FDM) 3D printer is investigating acrylonitrile butadiene styrene (ABS) thermoplastic manufacturing applications for long-duration space missions. This study assessed the feasibility of FDM 3D printing ABS thermoplastic customized mallet splints on site for Mars analogue crewmembers. Seven caliper measurements were taken of the right ring finger of 13 healthy Mars Desert Research Station mission crewmembers. These measurements were input into a free 3D modeling software program to create customized digital splint models. These digital files were uploaded to a desktop FDM 3D printer and custom splints were printed on site with ABS thermoplastic. Splint fit was assessed via subject feedback. Joint active range of motion was recorded when the splint was worn briefly. The time it took the software program to digitally render each splint model was less than 2 min and 30 s. The print duration for the splints ranged from 21 to 29 min. All 13 subjects reported that their 3D printed custom mallet splints fit securely and comfortably. All splints permitted full active range of motion of the proximal interphalangeal joint (0-100°) while maintaining the distal interphalangeal joint in extension. It is feasible to 3D print functional ABS thermoplastic custom mallet splints on site for Mars analogue crewmembers. This technology could be used clinically in the future when a custom mallet splint is required in a remote, resource-constrained setting.

  8. Assessment of On-site sanitation system on local groundwater regime in an alluvial aquifer

    Science.gov (United States)

    Quamar, Rafat; Jangam, C.; Veligeti, J.; Chintalapudi, P.; Janipella, R.

    2017-12-01

    The present study is an attempt to study the impact of the On-site sanitation system on the groundwater sources in its vicinity. The study has been undertaken in the Agra city of Yamuna sub-basin. In this context, sampling sites (3 nos) namely Pandav Nagar, Ayodhya Kunj and Laxmi Nagar were selected for sampling. The groundwater samples were analyzed for major cations, anions and faecal coliform. Critical parameters namely chloride, nitrate and Faecal coliform were considered to assess the impact of the On-site sanitation systems. The analytical results shown that except for chloride, most of the samples exceeded the Bureau of Indian Standard limits for drinking water for all the other analyzed parameters, i.e., nitrate and faecal coliform in the first two sites. In Laxmi Nagar, except for faecal coliform, all the samples are below the BIS limits. In all the three sites, faecal coliform was found in majority of the samples. A comparison of present study indicates that the contamination of groundwater in alluvial setting is less as compared to hard rock where On-site sanitation systems have been implemented.

  9. Assessment of On-site sanitation system on local groundwater regime in an alluvial aquifer

    Science.gov (United States)

    Quamar, Rafat; Jangam, C.; Veligeti, J.; Chintalapudi, P.; Janipella, R.

    2017-06-01

    The present study is an attempt to study the impact of the On-site sanitation system on the groundwater sources in its vicinity. The study has been undertaken in the Agra city of Yamuna sub-basin. In this context, sampling sites (3 nos) namely Pandav Nagar, Ayodhya Kunj and Laxmi Nagar were selected for sampling. The groundwater samples were analyzed for major cations, anions and faecal coliform. Critical parameters namely chloride, nitrate and Faecal coliform were considered to assess the impact of the On-site sanitation systems. The analytical results shown that except for chloride, most of the samples exceeded the Bureau of Indian Standard limits for drinking water for all the other analyzed parameters, i.e., nitrate and faecal coliform in the first two sites. In Laxmi Nagar, except for faecal coliform, all the samples are below the BIS limits. In all the three sites, faecal coliform was found in majority of the samples. A comparison of present study indicates that the contamination of groundwater in alluvial setting is less as compared to hard rock where On-site sanitation systems have been implemented.

  10. Optimal method of ecological restoration of degraded ecosystem using goal programming

    Science.gov (United States)

    Sun, Ling; Zhu, Zesheng

    2017-08-01

    Ecological restoration of degraded wetland ecosystem can be achieved by planning experts according to ground investigation, but with low efficiencies. We report that satellite sensors, maximizing ecosystem service values and minimizing ecological restoration cost improve ecological restoration efficiency. In particular, linear goal programming (LGP), an optimal programming, improves ecological restoration efficiency by more than 250% in the return on investment of ecological restoration, using TM satellite as area sensors. LGP also enables efficient introduction of optimal management into ecological restoration of degraded wetland ecosystem.

  11. ALERTES-SC3 Early Warning System prototype for South Iberian Peninsula: on-site approach.

    Science.gov (United States)

    Pazos, Antonio; Lopez de Mesa, Mireya; Gallego Carrasco, Javier; Martín Davila, José; Rioja del Rio, Carlos; Morgado, Arturo; Vera, Angel; Ciberia, Angel; Cabieces, Roberto; Strollo, Angelo; Hanka, Winfried; Carranza, Marta

    2016-04-01

    In recent years several Earthquake Early Warning Systems (EEWS) have been developed for different parts of the world. The area between SW Cape St. Vicente and the Strait of Gibraltar is one of the most seismically active zones in the Ibero-Maghrebian region, with predominantly moderate and superficial seismicity, but also big events with associated tsunamis are well documented in the area, like the 1755 Lisbon earthquake. In the frame of the ALERT-ES (2011-2013) and ALERTES-RIM (2014-2016) Spanish projects, the ALERTES-SC3 EEWS, regional approach, prototype has been developed at the Royal Spanish Navy Observatory (ROA) and is being tested in near real time for south Iberia. This prototype, based on the SeisComP3 software package, is largely based on algorithms derived from the analysis of the first seconds of the P wave records. Calculation of several parameters are carried out, mainly the characteristic period (τc) and the displacement peak (Pd), but also the velocity peak (Pv), the maximum period (τPmáx), among others. In order to warm the areas closest to the hypocentre, places located inside the "blind zone", a on-site EEWS has also been developed by ROA and integrated in the ALERTES-SC3 prototype. From the on-site approach, a warm level is declared from one station as a function of the estimated characteristic period (τc) and the displacement Peak (Pd), although the earthquake location and therefore the lead time available remains unknown. This on-site EEWS is being tested in several Western Mediterranean net (WM) stations as ARNO (Arenosillo, Huelva,Spain) or CHAS (Chafarinas island, North Africa, Spain). Also an on-site low cost station is being developed based in low cost accelerometers. In this work the current state of the on-site EEWS developed, its integration in the ALERTES-SC3 EEWS system and the low cost seismic stations are shown.

  12. Testing the applicability of rapid on-site enzymatic activity detection for surface water monitoring

    Science.gov (United States)

    Stadler, Philipp; Vogl, Wolfgang; Juri, Koschelnik; Markus, Epp; Maximilian, Lackner; Markus, Oismüller; Monika, Kumpan; Peter, Strauss; Regina, Sommer; Gabriela, Ryzinska-Paier; Farnleitner Andreas, H.; Matthias, Zessner

    2015-04-01

    On-site detection of enzymatic activities has been suggested as a rapid surrogate for microbiological pollution monitoring of water resources (e.g. using glucuronidases, galactosidases, esterases). Due to the possible short measuring intervals enzymatic methods have high potential as near-real time water quality monitoring tools. This presentation describes results from a long termed field test. For twelve months, two ColiMinder devices (Vienna Water Monitoring, Austria) for on-site determination of enzymatic activity were tested for stream water monitoring at the experimental catchment HOAL (Hydrological Open Air Laboratory, Center for Water Resource Systems, Vienna University of Technology). The devices were overall able to follow and reflect the diverse hydrological and microbiological conditions of the monitored stream during the test period. Continuous data in high temporal resolution captured the course of enzymatic activity in stream water during diverse rainfall events. The method also proofed sensitive enough to determine diurnal fluctuations of enzymatic activity in stream water during dry periods. The method was able to capture a seasonal trend of enzymatic activity in stream water that matches the results gained from Colilert18 analysis for E. coli and coliform bacteria of monthly grab samples. Furthermore the comparison of ColiMinder data with measurements gained at the same test site with devices using the same method but having different construction design (BACTcontrol, microLAN) showed consistent measuring results. Comparative analysis showed significant differences between measured enzymatic activity (modified fishman units and pmol/min/100ml) and cultivation based analyses (most probable number, colony forming unit). Methods of enzymatic activity measures are capable to detect ideally the enzymatic activity caused by all active target bacteria members, including VBNC (viable but nonculturable) while cultivation based methods cannot detect VBNC

  13. Batch efficiency

    CERN Document Server

    Schwickerath, U; Uria, C; CERN. Geneva. IT Department

    2010-01-01

    A frequent source of concern for resource providers is the efficient use of computing resources in their centers. This has a direct impact on requests for new resources. There are two different but strongly correlated aspects to be considered: while users are mostly interested in a good turn-around time for their jobs, resource providers are mostly interested in a high and efficient usage of their available resources. Both things, the box usage and the efficiency of individual user jobs, need to be closely monitored so that the sources of the inefficiencies can be identified. At CERN, the Lemon monitoring system is used for both purposes. Examples of such sources are poorly written user code, inefficient access to mass storage systems, and dedication of resources to specific user groups. As a first step for improvements CERN has launched a project to develop a scheduler add-on that allows careful overloading of worker nodes that run idle jobs.

  14. Standard Guide for On-Site Inspection and Verification of Operation of Solar Domestic Hot Water Systems

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1987-01-01

    1.1 This guide covers procedures and test methods for conducting an on-site inspection and acceptance test of an installed domestic hot water system (DHW) using flat plate, concentrating-type collectors or tank absorber systems. 1.2 It is intended as a simple and economical acceptance test to be performed by the system installer or an independent tester to verify that critical components of the system are functioning and to acquire baseline data reflecting overall short term system heat output. 1.3 This guide is not intended to generate accurate measurements of system performance (see ASHRAE standard 95-1981 for a laboratory test) or thermal efficiency. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine th...

  15. [On-site measurement of landfill gas yield and verification of IPCC model].

    Science.gov (United States)

    Luo, Yu-Xiang; Wang, Wei; Gao, Xing-Bao

    2009-11-01

    In order to obtain the accurate yield of landfill gas in Yulongkeng Landfill, Shenzhen, improved pumping test was conducted. The methane production rates of the influence region were figured out as 14.67 x 10(-5), 9.46 x 10(-5), 9.55 x 10(-5), and 4.28 x 10(-5) m3/(t x h), respectively. According to the methane production rate, the whole methane yield of Yulongkeng Landfill in 2005 was 322 m3/h, which indicated that Yulongkeng Landfill had went into stationary phase and the recycle of landfill gas was not valuable. IPCC model was verified by the measured data. Degradation half life of the waste was the key parameter concerned to the prediction accuracy of IPCC model. In China, the degradable waste in municipal solid waste was mainly kitchen waste leading to a short degradation period, which caused the degradation half life was shorter than the proposed value in IPCC model. For the improvement in prediction accuracy of landfill gas yield, the model parameters should be adopted reasonably based on a full survey of waste characterization in China, which will boost the applicability of IPCC model.

  16. Degradation of ampicillin in pig manure slurry and an aqueous ampicillin solution using electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Byung Yeoup; Kim, Jae-Sung [Advanced Radiation Technology Institute (ARTI), Korea Atomic Energy Research Institute (KAERI), Jeongeup 580-185 (Korea, Republic of); Lee, Min Hee [Advanced Radiation Technology Institute (ARTI), Korea Atomic Energy Research Institute (KAERI), Jeongeup 580-185 (Korea, Republic of); Crop Production and Technology Major, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Lee, Kang Soo; Hwang, Seon Ah [Crop Production and Technology Major, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Cho, Jae Young [Bio-environmental Science Major, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)], E-mail: soilcosmos@chonbuk.co.kr

    2009-07-15

    This study was carried out to evaluate the efficiency of degradation of antibiotic ampicillin in pig manure slurry and an aqueous ampicillin solution with the use of electron beam irradiation as a function of the absorbed dose. The degradation efficiency of ampicillin was close to 95% at an absorbed dose of 10 kGy. The degradation of ampicillin followed a 'first-order' reaction rate with respect to absorbed dose. The results demonstrate that the electron beam irradiation technology is an effective means to remove antibiotics in manure and bodies of water.

  17. Kinetics analysis for development of a rate constant estimation model for ultrasonic degradation reaction of methylene blue.

    Science.gov (United States)

    Kobayashi, Daisuke; Honma, Chiemi; Matsumoto, Hideyuki; Takahashi, Tomoki; Kuroda, Chiaki; Otake, Katsuto; Shono, Atsushi

    2014-07-01

    Ultrasound has been used as an advanced oxidation method for wastewater treatment. Sonochemical degradation of organic compounds in aqueous solution occurs by pyrolysis and/or reaction with hydroxyl radicals. Moreover, kinetics of sonochemical degradation has been proposed. However, the effect of ultrasonic frequency on degradation rate has not been investigated. In our previous study, a simple model for estimating the apparent degradation rate of methylene blue was proposed. In this study, sonochemical degradation of methylene blue was performed at various frequencies. Apparent degradation rate constant was evaluated assuming that sonochemical degradation of methylene blue was a first-order reaction. Specifically, we focused on effects of ultrasonic frequency and power on rate constant, and the applicability of our proposed model was demonstrated. Using this approach, maximum sonochemical degradation rate was observed at 490 kHz, which agrees with a previous investigation into the effect of frequency on the sonochemical efficiency value evaluated by KI oxidation dosimetry. Degradation rate increased with ultrasonic power at every frequency. It was also observed that threshold power must be reached for the degradation reaction to progress. The initial methylene blue concentration and the apparent degradation rate constant have a relation of an inverse proportion. Our proposed model for estimating the apparent degradation rate constant using ultrasonic power and sonochemical efficiency value can apply to this study which extended the frequency and initial concentration range. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. [Microwave assisted UV electrodeless discharge lamp photochemical degradation of 4-chlorophenol in aquatic solutions].

    Science.gov (United States)

    Ai, Zhi-hui; Jiang, Jun-qing; Yang, Peng; Zhou, Tao; Lu, Xiao-hua

    2004-07-01

    A microwave assisted UV electrodeless discharge lamp system (MW/UV) was used for photo-degradation of 4CP simulated wastewater. In order to evaluate the degradation efficiency of 4CP, UV spectrophotometry and ion chromatography were used for determination of 4CP and Cl- respectively. The degradation rate in MW/UV system was higher than that in the UV system within 120min, which were 52.40% and 21.56% respectively. The degradation efficiency was improved by increasing pH value of the solution, aerating O2 gas, enhancing light intensity, or adding H2O2 oxidant. The degradation of 4CP under MW/UV accords with the first order kinetics equation.

  19. Experimental Analysis of the Potential Induced Degradation Effect on Organic Solar Cells

    Directory of Open Access Journals (Sweden)

    S. C. Akcaoğlu

    2017-01-01

    Full Text Available Renewable energy applications are increasing daily, and solar electricity, in the form of photovoltaics, is getting more and more important worldwide. As photovoltaics are connected both in series and in parallel, the panels are exposed to high potentials compared to the ground; thus, high voltage stress (HVS occurs. The scope of this paper is to analyze experimentally the potential induced degradation (PID in organic solar cells. To that end, organic solar cells are manufactured and are then undergone a series of voltage-dependent degradation and time-dependent voltage degradation tests. In addition to that, they are also exposed to gaseous oxygen, oxygen plasma, air degradation, and annealing, and the degradation effects are compared with PID results. From the analysis, it is apparent that annealing, air, gaseous oxygen, and oxygen plasma degradation have similar effects with PID, while due to simple diode characteristics, organic cells proved to be relatively durable to potential induced degradation. At low voltages (10 V, the organic cells withstood degradation adequately, with a drop of 23% in their initial efficiency. As voltage increased, the degradation rate increased considerably reaching a 93% efficiency drop when 30 V was applied for 20 minutes.

  20. Text segmentation in degraded historical document images

    Directory of Open Access Journals (Sweden)

    A.S. Kavitha

    2016-07-01

    Full Text Available Text segmentation from degraded Historical Indus script images helps Optical Character Recognizer (OCR to achieve good recognition rates for Hindus scripts; however, it is challenging due to complex background in such images. In this paper, we present a new method for segmenting text and non-text in Indus documents based on the fact that text components are less cursive compared to non-text ones. To achieve this, we propose a new combination of Sobel and Laplacian for enhancing degraded low contrast pixels. Then the proposed method generates skeletons for text components in enhanced images to reduce computational burdens, which in turn helps in studying component structures efficiently. We propose to study the cursiveness of components based on branch information to remove false text components. The proposed method introduces the nearest neighbor criterion for grouping components in the same line, which results in clusters. Furthermore, the proposed method classifies these clusters into text and non-text cluster based on characteristics of text components. We evaluate the proposed method on a large dataset containing varieties of images. The results are compared with the existing methods to show that the proposed method is effective in terms of recall and precision.

  1. Hydroxyl radical induced degradation of ibuprofen

    Energy Technology Data Exchange (ETDEWEB)

    Illés, Erzsébet, E-mail: erzsebet.illes@chem.u-szeged.hu [Institute of Chemistry, Research Group of Environmental Chemistry, University of Szeged, Szeged (Hungary); Institute of Isotopes, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary); Takács, Erzsébet [Institute of Isotopes, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary); Dombi, András [Institute of Chemistry, Research Group of Environmental Chemistry, University of Szeged, Szeged (Hungary); Gajda-Schrantz, Krisztina [Institute of Chemistry, Research Group of Environmental Chemistry, University of Szeged, Szeged (Hungary); Department of Inorganic and Analytical Chemistry, University of Szeged, Szeged (Hungary); EMPA, Laboratory for High Performance Ceramics, Duebendorf (Switzerland); Rácz, Gergely; Gonter, Katalin; Wojnárovits, László [Institute of Isotopes, Centre for Energy Research, Hungarian Academy of Sciences, Budapest (Hungary)

    2013-03-01

    Pulse radiolysis experiments were used to characterize the intermediates formed from ibuprofen during electron beam irradiation in a solution of 0.1 mmol dm{sup −3}. For end product characterization {sup 60}Co γ-irradiation was used and the samples were evaluated either by taking their UV–vis spectra or by HPLC with UV or MS detection. The reactions of {sup ·}OH resulted in hydroxycyclohexadienyl type radical intermediates. The intermediates produced in further reactions hydroxylated the derivatives of ibuprofen as final products. The hydrated electron attacked the carboxyl group. Ibuprofen degradation is more efficient under oxidative conditions than under reductive conditions. The ecotoxicity of the solution was monitored by Daphnia magna standard microbiotest and Vibrio fischeri luminescent bacteria test. The toxic effect of the aerated ibuprofen solution first increased upon irradiation indicating a higher toxicity of the first degradation products, then decreased with increasing absorbed dose. Highlights: ► In hydroxyl radical attack on the ring mainly hydroxylated products form ► The hydrated electron attacks the carboxyl group. ► Oxidative conditions are more effective in ibuprofen decomposition than reductive. ► Ecotoxicity of ibuprofen solution first increases then decreases with irradiation.

  2. Autophagic degradation of peroxisomes in mammals.

    Science.gov (United States)

    Zientara-Rytter, Katarzyna; Subramani, Suresh

    2016-04-15

    Peroxisomes are essential organelles required for proper cell function in all eukaryotic organisms. They participate in a wide range of cellular processes including the metabolism of lipids and generation, as well as detoxification, of hydrogen peroxide (H2O2). Therefore, peroxisome homoeostasis, manifested by the precise and efficient control of peroxisome number and functionality, must be tightly regulated in response to environmental changes. Due to the existence of many physiological disorders and diseases associated with peroxisome homoeostasis imbalance, the dynamics of peroxisomes have been widely examined. The increasing volume of reports demonstrating significant involvement of the autophagy machinery in peroxisome removal leads us to summarize current knowledge of peroxisome degradation in mammalian cells. In this review we present current models of peroxisome degradation. We particularly focus on pexophagy-the selective clearance of peroxisomes through autophagy. We also critically discuss concepts of peroxisome recognition for pexophagy, including signalling and selectivity factors. Finally, we present examples of the pathological effects of pexophagy dysfunction and suggest promising future directions. © 2016 Authors; published by Portland Press Limited.

  3. Obligate oil-degrading marine bacteria.

    Science.gov (United States)

    Yakimov, Michail M; Timmis, Kenneth N; Golyshin, Peter N

    2007-06-01

    Over the past few years, a new and ecophysiologically unusual group of marine hydrocarbon-degrading bacteria - the obligate hydrocarbonoclastic bacteria (OHCB) - has been recognized and shown to play a significant role in the biological removal of petroleum hydrocarbons from polluted marine waters. The introduction of oil or oil constituents into seawater leads to successive blooms of a relatively limited number of indigenous marine bacterial genera--Alcanivorax, Marinobacter, Thallassolituus, Cycloclasticus, Oleispira and a few others (the OHCB)--which are present at low or undetectable levels before the polluting event. The types of OHCB that bloom depend on the latitude/temperature, salinity, redox and other prevailing physical-chemical factors. These blooms result in the rapid degradation of many oil constituents, a process that can be accelerated further by supplementation with limiting nutrients. Genome sequencing and functional genomic analysis of Alcanivorax borkumensis, the paradigm of OHCB, has provided significant insights into the genomic basis of the efficiency and versatility of its hydrocarbon utilization, the metabolic routes underlying its special hydrocarbon diet, and its ecological success. These and other studies have revealed the potential of OHCB for multiple biotechnological applications that include not only oil pollution mitigation, but also biopolymer production and biocatalysis.

  4. Degradation of Silicone Encapsulants in CPV Optics: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David C.; Tappan, Ian A.; Cai, Can; Dauskardt, Reinhold H.

    2016-07-01

    High efficiency multijunction solar cells in terrestrial concentrator photovoltaic (CPV) modules are becoming an increasingly cost effective and viable option in utility scale power generation. As with other utility scale photovoltaics, CPV modules need to guarantee operational lifetimes of at least 25 years. The reliability of optical elements in CPV modules poses a unique materials challenge due to the increased UV irradiance and enhanced temperature cycling associated with concentrated solar flux. The polymeric and thin film materials used in the optical elements are especially susceptible to UV damage, diurnal temperature cycling and active chemical species from the environment. We used fracture mechanics approaches to study the degradation modes including: the adhesion between the encapsulant and the cell or secondary optical element; and the cohesion of the encapsulant itself. Understanding the underlying mechanisms of materials degradation under elevated stress conditions is critical for commercialization of CPV technology and can offer unique insights into degradation modes in similar encapsulants used in other photovoltaic modules.

  5. Determination of Polymers Thermal Degradation by Color Change Analysis

    Directory of Open Access Journals (Sweden)

    Andrés Felipe Rojas González

    2016-01-01

    Full Text Available Context: It has been observed that thermal degradation of thermoplastic polymers, when they are reprocessed by injection, extrusion and extrusion / injection, undergo color changes in the product, although it not has been established as this change occurs. Method: It analyzed the effect on thermal degradation caused by polymer type, processing type, polymer grade, rotation speed of the extrusion screw and number of reprocessing, which is quantified by the color change using an empirical equation, with experimental data obtained by analysis through a microcolor colorimeter. Results: It was found that the color change analysis provides information about progress of the thermal degradation and stability of thermoplastic polymers, which are undergoing to multiple reprocessing events and processes. Conclusions: It was established that this technique can be implemented as a simple and efficient measure of thermoplastic products quality control, according to their color change.

  6. Endosulfan Degradation by Selected Strains of Plant Growth Promoting Rhizobacteria.

    Science.gov (United States)

    Rani, Rupa; Kumar, Vipin

    2017-07-01

    Sixty endosulfan tolerant bacterial strains were isolated from pesticide stressed agricultural soils. Five most tolerant strains were tested for plant growth promoting (PGP) activities and endosulfan degradation under different optimizing conditions in broth and soil. The strains PRB101 and PRB77 were the most efficient in terms of endosulfan degradation and PGP activities and showed solubilization indexes of 3.3 and 3.1 mm, indole acetic acid production of 71 and 68 μg mL-1, siderophore zones of 13 mm each at the recommended dosage, respectively. Hydrogen cyanide and ammonia production remained unaffected in the presence of endosulfan. PRB101 and PRB77 strains were able to degrade 74% and 70% of endosulfan in broth and 67% and 63% in soil, respectively. Based on 16S rDNA analysis, the strains PRB101 and PRB77 exhibited 99% homology with Bacillus sp. KF984414 and Bacillus sp. LN849696, respectively.

  7. Radiation degradation of silk protein

    Energy Technology Data Exchange (ETDEWEB)

    Pewlong, W.; Sudatis, B. [Office of Atomic Energy for Peace, Bangkok (Thailand); Takeshita, Hidefumi; Yoshii, Fumio; Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2000-03-01

    Silk fibroin fiber from the domesticated silkworm Bombyx mori was irradiated using an electron beam accelerator to investigate the application of the radiation degradation technique as a means to solubilize fibroin. The irradiation caused a significant degradation of the fiber. The tensile strength of fibroin fiber irradiated up to 2500 kGy decreased rapidly with increasing dose. The presence of oxygen in the irradiation atmosphere enhanced degradation of the tensile strength. The solubilization of irradiated fibroin fiber was evaluated using the following three kinds of solutions: a calcium chloride solution(CaCl{sub 2}/C{sub 2}H{sub 5}OH/H{sub 2}O=1:2:8 in mole ratio), a hydrochloric acid (0.5 N) and a distilled water. Dissolution of fibroin fiber into these solutions was significantly enhanced by irradiation. Especially, an appreciable amount of water soluble proteins was extracted by a distilled water. (author)

  8. HYDROCARBON-DEGRADING BACTERIA AND SURFACTANT ACTIVITY

    Energy Technology Data Exchange (ETDEWEB)

    Brigmon, R; Topher Berry, T; Grazyna A. Plaza, G; jacek Wypych, j

    2006-08-15

    Fate of benzene ethylbenzene toluene xylenes (BTEX) compounds through biodegradation was investigated using two different bacteria, Ralstonia picketti (BP-20) and Alcaligenes piechaudii (CZOR L-1B). These bacteria were isolated from extremely polluted petroleum hydrocarbon contaminated soils. PCR and Fatty Acid Methyl Ester (FAME) were used to identify the isolates. Biodegradation was measured using each organism individually and in combination. Both bacteria were shown to degrade each of the BTEX compounds. Alcaligenes piechaudii biodegraded BTEXs more efficiently while mixed with BP-20 and individually. Biosurfactant production was observed by culture techniques. In addition 3-hydroxy fatty acids, important in biosurfactant production, was observed by FAME analysis. In the all experiments toluene and m+p- xylenes were better growth substrates for both bacteria than the other BTEX compounds. In addition, the test results indicate that the bacteria could contribute to bioremediation of aromatic hydrocarbons (BTEX) pollution increase biodegradation through the action by biosurfactants.

  9. Chromium related degradation of solid oxide fuel cells; Chrom-bezogene Degradation von Festoxid-Brennstoffzellen

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, Anita

    2011-05-04

    Solid Oxide Fuel Cells (SOFCs) offer a high potential for application as an auxiliary power unit (APU) for heavy goods vehicles as well as combined heat and power (CHP) systems. SOFCs are especially attractive due to their high efficiencies and the use of different fuel types. However, optimization in terms of long term stability and costs are still necessary. This work characterized the degradation of SOFCs with lanthanum strontium manganite (LSM) cathodes under chromium influence. Galvanostatic cell tests were carried out at 800 C with operation times from 250 - 3000 h and variation of the chromium source and current density. The current densities of j = 0 (A)/(cm{sup 2}), j = 0,3 (A)/(cm{sup 2}) and j = 0,5 (A)/(cm{sup 2}) were applied. The high temperature ferritic alloy Crofer22APU was used as a chromium source. Variation of the chromium source was realized by coating the Crofer22APU insert with the chromium retention layer Mn{sub 3}O{sub 4} and the cathode contact layer LCC10. Cell degradation was analyzed with regard to cell voltage, current density and area specific resistance (ASR). Microstructural alterations of the cathode as well as chromium content and distribution across the cell were investigated after completion of the cell tests. For cells with a chromium source present and operation with a nonzero current density, the course of cell degradation was divided into three phases: a run-in, weak linear degradation and strong linear degradation. A decrease of the chromium release rate by means of different coatings stretched the course of degradation along the timescale. Strong degradation, which is characterized by a significant increase in ASR as well as a decrease of current density at the operating point, was only observed when a chromium source in the setup was comb ined with operation of the cell with a non-zero current density. Operation of the cell with a chromium source but no current density caused a degradation of current density at the

  10. Degradation of Synthetic Dyes by Laccases – A Mini-Review

    Directory of Open Access Journals (Sweden)

    Legerská Barbora

    2016-06-01

    Full Text Available Laccases provide a promising future as a tool to be used in the field of biodegradation of synthetic dyes with different chemical structures. These enzymes are able to oxidize a wide range of phenolic substrates without the presence of additional co-factors. Laccases have been confirmed for their potential of synthetic dye degradation from wastewater and degradation products of these enzymatic reactions become less toxic than selected dyes. This study discusses the potential of laccase enzymes as agents for laccase-catalyzed degradation in terms of biodegradation efficiency of synthetic dyes, specifically: azo dyes, triphenylmethane, indigo and anthraquinone dyes. Review also summarizes the laccase-catalyzed degradation mechanisms of the selected synthetic dyes, as well as the degradation products and the toxicity of the dyes and their degradation products.

  11. The Science of Battery Degradation

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, John P. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Materials Physics; El Gabaly Marquez, Farid [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Materials Physics; McCarty, Kevin [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Materials Physics; Sugar, Joshua Daniel [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Materials Physics; Talin, Alec A. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Materials Physics; Fenton, Kyle R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Power Sources Design and Development; Nagasubramanian, Ganesan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Power Sources Design and Development; Harris, Charles Thomas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Nanosystems Synthesis/Analysis; Jungjohann, Katherine Leigh [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Nanosystems Synthesis/Analysis; Hayden, Carl C. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Combustion Chemistry Dept.; Kliewer, Christopher Jesse [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Combustion Chemistry Dept.; Hudak, Nicholas S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Power Sources Research and Development; Leung, Kevin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Nanostructure Physics; McDaniel, Anthony H. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Hydrogen and Combustion Technology; Tenney, Craig M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Chemical and Biological Systems; Zavadil, Kevin R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Materials Lab.

    2015-01-01

    This report documents work that was performed under the Laboratory Directed Research and Development project, Science of Battery Degradation. The focus of this work was on the creation of new experimental and theoretical approaches to understand atomistic mechanisms of degradation in battery electrodes that result in loss of electrical energy storage capacity. Several unique approaches were developed during the course of the project, including the invention of a technique based on ultramicrotoming to cross-section commercial scale battery electrodes, the demonstration of scanning transmission x-ray microscopy (STXM) to probe lithium transport mechanisms within Li-ion battery electrodes, the creation of in-situ liquid cells to observe electrochemical reactions in real-time using both transmission electron microscopy (TEM) and STXM, the creation of an in-situ optical cell utilizing Raman spectroscopy and the application of the cell for analyzing redox flow batteries, the invention of an approach for performing ab initio simulation of electrochemical reactions under potential control and its application for the study of electrolyte degradation, and the development of an electrochemical entropy technique combined with x-ray based structural measurements for understanding origins of battery degradation. These approaches led to a number of scientific discoveries. Using STXM we learned that lithium iron phosphate battery cathodes display unexpected behavior during lithiation wherein lithium transport is controlled by nucleation of a lithiated phase, leading to high heterogeneity in lithium content at each particle and a surprising invariance of local current density with the overall electrode charging current. We discovered using in-situ transmission electron microscopy that there is a size limit to lithiation of silicon anode particles above which particle fracture controls electrode degradation. From electrochemical entropy measurements, we discovered that entropy

  12. Effective cellulose degradation by a mixed-culture system composed of a cellulolytic Clostridium and aerobic non-cellulolytic bacteria.

    Science.gov (United States)

    Kato, Souichiro; Haruta, Shin; Cui, Zong Jun; Ishii, Masaharu; Igarashi, Yasuo

    2004-12-27

    A stable cellulose-degrading microflora enriched from composting materials has been analyzed in our laboratory. Cellulose-degrading efficiency of an anaerobic cellulolytic isolate, Clostridium straminisolvens CSK1, was remarkably lower than that of the original microflora. We successfully constructed bacterial communities with effective cellulose degradation by mixing C. straminisolvens CSK1 with aerobic non-cellulolytic bacteria isolated from the original microflora. Comparison of the cellulose degradation processes of the pure culture of C. straminisolvens CSK1 and the mixed-culture indicated that non-cellulolytic bacteria essentially contribute to cellulose degradation by supplying anaerobic environment, consuming metabolites, which otherwise deteriorate the cellulolytic activity, and by neutralizing pH.

  13. Fuzzy Logic Approach to Diagnosis of Feedwater Heater Performance Degradation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yeon Kwan; Kim, Hyeon Min; Heo, Gyun Young [Kyung Hee University, Yongin (Korea, Republic of); Sang, Seok Yoon [Engineering and Technical Center, Korea Hydro, Daejeon (Korea, Republic of)

    2014-08-15

    Since failure in, damage to, and performance degradation of power generation components in operation under harsh environment of high pressure and high temperature may cause both economic and human loss at power plants, highly reliable operation and control of these components are necessary. Therefore, a systematic method of diagnosing the condition of these components in its early stages is required. There have been many researches related to the diagnosis of these components, but our group developed an approach using a regression model and diagnosis table, specializing in diagnosis relating to thermal efficiency degradation of power plant. However, there was a difficulty in applying the method using the regression model to power plants with different operating conditions because the model was sensitive to value. In case of the method that uses diagnosis table, it was difficult to find the level at which each performance degradation factor had an effect on the components. Therefore, fuzzy logic was introduced in order to diagnose performance degradation using both qualitative and quantitative results obtained from the components' operation data. The model makes performance degradation assessment using various performance degradation variables according to the input rule constructed based on fuzzy logic. The purpose of the model is to help the operator diagnose performance degradation of components of power plants. This paper makes an analysis of power plant feedwater heater by using fuzzy logic. Feedwater heater is one of the core components that regulate life-cycle of a power plant. Performance degradation has a direct effect on power generation efficiency. It is not easy to observe performance degradation of feedwater heater. However, on the other hand, troubles such as tube leakage may bring simultaneous damage to the tube bundle and therefore it is the object of concern in economic aspect. This study explains the process of diagnosing and verifying typical

  14. On-site phytoremediation applicability assessment in Alur Ilmu, Universiti Kebangsaan Malaysia based on spatial and pollution removal analyses.

    Science.gov (United States)

    Mahmud, Mohd Hafiyyan; Lee, Khai Ern; Goh, Thian Lai

    2017-10-01

    The present paper aims to assess the phytoremediation performance based on pollution removal efficiency of the highly polluted region of Alur Ilmu urban river for its applicability of on-site treatment. Thirteen stations along Alur Ilmu were selected to produce thematic maps through spatial distribution analysis based on six water quality parameters of Malaysia's Water Quality Index (WQI) for dry and raining seasons. The maps generated were used to identify the highly polluted region for phytoremediation applicability assessment. Four free-floating plants were tested in treating water samples from the highly polluted region under three different conditions, namely controlled, aerated and normal treatments. The selected free-floating plants were water hyacinth (Eichhornia crassipes), water lettuce (Pistia stratiotes), rose water lettuce (Pistia sp.) and pennywort (Centella asiatica). The results showed that Alur Ilmu was more polluted during dry season compared to raining season based on the water quality analysis. During dry season, four parameters were marked as polluted along Alur Ilmu, namely dissolve oxygen (DO), 4.72 mg/L (class III); ammoniacal nitrogen (NH3-N), 0.85 mg/L (class IV); total suspended solid (TSS), 402 mg/L (class V) and biological oxygen demand (BOD), 3.89 mg/L (class III), whereas, two parameters were classed as polluted during raining season, namely total suspended solid (TSS), 571 mg/L (class V) and biological oxygen demand (BOD), 4.01 mg/L (class III). The thematic maps generated from spatial distribution analysis using Kriging gridding method showed that the highly polluted region was recorded at station AL 5. Hence, water samples were taken from this station for pollution removal analysis. All the free-floating plants were able to reduce TSS and COD in less than 14 days. However, water hyacinth showed the least detrimental effect from the phytoremediation process compared to other free-floating plants, thus made it a suitable free

  15. 78 FR 42804 - SST Truck Company, LLC, a Navistar, Inc. Company Including On-Site Leased Workers From Employee...

    Science.gov (United States)

    2013-07-17

    ... Employment and Training Administration SST Truck Company, LLC, a Navistar, Inc. Company Including On- Site... Insurance (UI) Wages Were Reported Through International Truck and Engine Corporation, Garland, Texas..., applicable to workers of SST Truck Company, LLC, a Navistar, Inc. company, Garland, Texas, including on-site...

  16. 75 FR 28296 - Denso Manufacturing of Michigan Including On-Site Leased Workers From Adecco Employment Services...

    Science.gov (United States)

    2010-05-20

    ... Employment and Training Administration Denso Manufacturing of Michigan Including On-Site Leased Workers From..., 2009, applicable to workers of Denso Manufacturing of Michigan, including leased workers from Adecco... Group were employed on-site at the Battle Creek, Michigan location of Denso Manufacturing of Michigan...

  17. 75 FR 28296 - Clark Engineering Co., Inc., Including On-Site Leased Workers From Kelly Services and Qualified...

    Science.gov (United States)

    2010-05-20

    ... Employment and Training Administration Clark Engineering Co., Inc., Including On-Site Leased Workers From... Worker Adjustment Assistance on January 7, 2010, applicable to workers of Clark Engineering Co., Inc... were employed on-site at the Owosso, Michigan location of Clark Engineering Co., Inc. The Department...

  18. 76 FR 35025 - Nokia, Inc.; a Subsidiary of Nokia Group; Including On-Site Leased Workers From ATC Logistics and...

    Science.gov (United States)

    2011-06-15

    ... Workers From ATC Logistics and Electronics and Adecco Fort Worth, TX; Amended Certification Regarding...., a subsidiary of Nokia Group, including on-site leased workers from ATC Logistics and Electronics... Nokia, Inc., a subsidiary of Nokia Group, including on-site leased workers from ATC Logistics and...

  19. 75 FR 11920 - General Electric Lighting-Ravenna Lamp Plant, Lighting Division, Including On-Site Leased Workers...

    Science.gov (United States)

    2010-03-12

    ... Employment and Training Administration General Electric Lighting-Ravenna Lamp Plant, Lighting Division... Electric Lighting-Ravenna Lamp Plant, Lighting Division, including on-site leased workers from DeVore... Electric Lighting-Ravenna Lamp Plant, Lighting Division, including on-site leased workers from DeVore...

  20. 75 FR 41522 - Hewlett Packard, Technical Support Call Center, Including On-Site Leased Workers From Manpower...

    Science.gov (United States)

    2010-07-16

    ... Employment and Training Administration Hewlett Packard, Technical Support Call Center, Including On-Site... workers of Hewlett Packard, Technical Support Call Center, including on-site leased workers from Manpower..., Idaho location of Hewlett Packard, Technical Support Call Center. The Department has determined that...