WorldWideScience

Sample records for nitrobenzene reduction catalized

  1. Reduction of nitrobenzene by the catalyzed Fe/Cu process

    Institute of Scientific and Technical Information of China (English)

    XU Wenying; LI Ping; FAN Jinhong

    2008-01-01

    The polarization behavior of the couple Fe/Cu in 100 mg/L nitrobenzene aqueous solution was studied using Evans coupling diagrams. The results indicated that the iron corrosion was limited by both anodic and cathodic half-cell reactions under the neutral conditions and cathodically controlled under the alkaline conditions. Batch experiments were performed to study the effect of solution pH, reaction duration, concentration, type of electrolyte and dissolved oxygen (DO) on the reduction of nitrobenzene by the catalyzed Fe/Cu process. This process proved effective in the pH range of 3 to 11. The conversion efficiency of nitrobenzene at pH ≈ 10.1 was almost the same as that under highly acid conditions (pH ≈ 3). The degradation of nitrobenzene fell into two phases: adsorption and surface reduction, and the influence of adsorption and mass transfer became more extensive with solution concentration. The reduction rate decreased in the presence of DO in the solution, indicating that a need for aeration was eliminated in the catalyzed Fe/Cu process. Accordingly, spending on energy consumption would be reduced. Economic analysis indicated that merely 0.05 kg was required for the treatment of a ton of nitrobenzene-containing water with pH from 3 to 11. The catalyzed Fe/Cu process is cost-effective and of practical value.

  2. Reduction of nitrobenzene with alkaline ascorbic acid: Kinetics and pathways

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Chenju, E-mail: cliang@nchu.edu.tw [Department of Environmental Engineering, National Chung Hsing University 250, Kuo-kuang Road, Taichung 402, Taiwan (China); Lin, Ya-Ting [Department of Environmental Engineering, Chung Yuan Christian University, 200 Chung Pei Road, Chung Li District, Taoyuan City 320, Taiwan (China); Shiu, Jia-Wei [Department of Environmental Engineering, National Chung Hsing University 250, Kuo-kuang Road, Taichung 402, Taiwan (China)

    2016-01-25

    Highlights: • Alkaline ascorbic acid (a.k.a. vitamin C) is capable of reductively degrading NB. • The pH above the pK{sub a2} of ascorbic acid increases reductive electron transfer to NB. • The rate equation for the reactions between NB and AA is determined. • NSB, AZOXY, and AZO are identified as intermediates and aniline as a final product. • Alkaline pH is essential for AA remediation of NB contaminated soils. - Abstract: Alkaline ascorbic acid (AA) exhibits the potential to reductively degrade nitrobenzene (NB), which is the simplest of the nitroaromatic compounds. The nitro group (NO{sub 2}{sup −}) of NB has a +III oxidation state of the N atom and tends to gain electrons. The effect of alkaline pH ranging from 9 to 13 was initially assessed and the results demonstrated that the solution pH, when approaching or above the pK{sub a2} of AA (11.79), would increase reductive electron transfer to NB. The rate equation for the reactions between NB and AA at pH 12 can be described as r = ((0.89 ± 0.11) × 10{sup −4} mM{sup 1−(a} {sup +} {sup b)} h{sup −1}) × [NB]{sup a} {sup =} {sup 1.35} {sup ±} {sup 0.10}[AA]{sup b} {sup =} {sup 0.89} {sup ±} {sup 0.01}. The GC/MS analytical method identified nitrosobenzene, azoxybenzene, and azobenzene as NB reduction intermediates, and aniline (AN) as a final product. These experimental results indicate that the alkaline AA reduction of NB to AN mainly proceeds via the direct route, consisting of a series of two-electron or four-electron transfers, and the condensation reaction plays a minor route. Preliminary evaluation of the remediation of spiked NB contaminated soils revealed that maintenance of alkaline pH and a higher water to soil ratio are essential for a successful alkaline AA application.

  3. Graphene oxide-facilitated reduction of nitrobenzene in sulfide-containing aqueous solutions.

    Science.gov (United States)

    Fu, Heyun; Zhu, Dongqiang

    2013-05-07

    The main objective of this study was to test the possibility that graphene-based nanomaterials can mediate environmentally relevant abiotic redox reactions of organic contaminants. We investigated the effect of graphene oxide (GO) on the reduction of nitrobenzene by Na2S in aqueous solutions. With the presence of GO (typically 5 mg/L), the observed pseudofirst-order rate constant (kobs) for the reduction of nitrobenzene was raised by nearly 2 orders of magnitude (from 7.83 × 10(-5) h(-1) to 7.77 × 10(-3) h(-1)), strongly suggesting reaction mediation by GO. As reflected by the combined spectroscopic analyses, GO was reduced in the beginning of the reaction, and hence the reduced GO (RGO) mediated the reduction of nitrobenzene. It was proposed that the zigzag edges of RGO acted as the catalytic active sites, while the basal plane of RGO served as the conductor for the electron transfer during the catalytic process. Furthermore, changing the pH (5.9-9.1) and the presence of dissolved humic acid (10 mg TOC/L) were found to greatly influence the catalytic activity of RGO. The results imply that graphene-based nanomaterials may effectively mediate the reductive transformation of nitroaromatic compounds and can contribute to the natural attenuation and remediation of these chemicals.

  4. Design of an ultrasmall Au nanocluster-CeO2 mesoporous nanocomposite catalyst for nitrobenzene reduction.

    Science.gov (United States)

    Chong, Hanbao; Li, Peng; Xiang, Ji; Fu, Fangyu; Zhang, Dandan; Ran, Xiaorong; Zhu, Manzhou

    2013-08-21

    In this work we are inspired to explore gold nanoclusters supported on mesoporous CeO2 nanospheres as nanocatalysts for the reduction of nitrobenzene. Ultrasmall Au nanoclusters (NCs) and mesoporous CeO2 nanospheres were readily synthesized and well characterized. Due to their ultrasmall size, the as-prepared Au clusters can be easily absorbed into the mesopores of the mesoporous CeO2 nanospheres. Owing to the unique mesoporous structure of the CeO2 support, Au nanoclusters in the Au@CeO2 may effectively prevent the aggregation which usually results in a rapid decay of the catalytic activity. It is notable that the ultrasmall gold nanoclusters possess uniform size distribution and good dispersibility on the mesoporous CeO2 supports. Compared to other catalyst systems with different oxide supports, the as-prepared Au nanocluster-CeO2 nanocomposite nanocatalysts showed efficient catalytic performance in transforming nitrobenzene into azoxybenzene. In addition, a plausible mechanism was deeply investigated to explain the transforming process. Au@CeO2 exhibited efficient catalytic activity for reduction of nitrobenzene. This strategy may be easily extended to fabricate many other heterogeneous catalysts including ultrasmall metal nanoclusters and mesoporous oxides.

  5. Nickel Decorated on Phosphorous-Doped Carbon Nitride as an Efficient Photocatalyst for Reduction of Nitrobenzenes

    Science.gov (United States)

    Kumar, Anurag; Kumar, Pawan; Joshi, Chetan; Manchanda, Manvi; Boukherroub, Rabah; Jain, Suman L.

    2016-01-01

    Nickel nanoparticle-decorated phosphorous-doped graphitic carbon nitride (Ni@g-PC3N4) was synthesized and used as an efficient photoactive catalyst for the reduction of various nitrobenzenes under visible light irradiation. Hydrazine monohydrate was used as the source of protons and electrons for the intended reaction. The developed photocatalyst was found to be highly active and afforded excellent product yields under mild experimental conditions. In addition, the photocatalyst could easily be recovered and reused for several runs without any detectable leaching during the reaction.

  6. Poly(N-isopropylacrylamide-co-methacrylic acid microgel stabilized copper nanoparticles for catalytic reduction of nitrobenzene

    Directory of Open Access Journals (Sweden)

    Farooqi Zahoor H.

    2015-09-01

    Full Text Available Poly(N-isopropylacrylamide-co-methacrylic acid microgels [p(NIPAM-co-MAAc] were synthesized by precipitation polymerization of N-isopropylacrylamide and methacrylic acid in aqueous medium. These microgels were characterized by dynamic light scattering and Fourier transform infrared spectroscopy. These microgels were used as micro-reactors for in situ synthesis of copper nanoparticles using sodium borohydride (NaBH4 as reducing agent. The hybrid microgels were used as catalysts for the reduction of nitrobenzene in aqueous media. The reaction was performed with different concentrations of cat­alyst and reducing agent. A linear relationship was found between apparent rate constant (kapp and amount of catalyst. When the amount of catalyst was increased from 0.13 to 0.76 mg/mL then kapp was increased from 0.03 to 0.14 min-1. Activation parameters were also determined by performing reaction at two different temperatures. The catalytic process has been discussed in terms of energy of activation, enthalpy of activation and entropy of activation. The synthesized particles were found to be stable even after 14 weeks and showed catalytic activity for the reduction of nitrobenzene.

  7. [Reduction of nitrobenzene by iron oxides bound Fe(II) system at different pH values].

    Science.gov (United States)

    Luan, Fu-Bo; Xie, Li; Li, Jun; Zhou, Qi

    2009-07-15

    Batch tests were conducted to investigate the reductive transformation of nitrobenzene by goethite, hematite, magnetite and steel converter slag bound Fe(II) system. And the reduction mechanism was explored at different pH values. Experimental results showed that hematite, magnetite and steel converter slag could adsorb Fe(II) on surfaces and form iron oxides bound Fe(II) system at pH from 6.5 to 7.0. The systems had strong reductive capacity and could reduce nitrobenzene to aniline. The reduction efficiency of nitrobenzene in surface bound Fe(II) system followed the sequence of magnetite, hematite and steel converter slag from high to low. The reduction efficiency of hematite and magnetite system increased with pH increasing. While it was almost pH independent in steel converter slag system. Although goethite adsorbed most of Fe(II) in solution, the adsorbed Fe(II) had no reductive activity for nitrobenzene. At pH 6.0, small amount of Fe(II) was adsorbed on magnetite and hematite and the systems did not show reductive activity for nitrobenzene. However, steel converter slag could adsorb Fe(II) at pH 6.0 and reduction efficiency almost equaled to the value at pH 7.0. When pH was above 7.5, dissolved Fe(II) could be converted to Fe(OH)2 and the newly formed Fe(OH)2 became the main redactor in the system. Under alkali condition, the presence of iron oxides inhibited the reduction capacity of system.

  8. [Electrochemical reduction characteristics of nitro-benzene compounds at the copper electrode and the influence of pH on reduction].

    Science.gov (United States)

    Xu, Wen-ying; Fan, Jin-hong; Gao, Ting-yao

    2005-03-01

    The electrochemical reduction characteristics of nitro-benzene compounds were investigated using cyclic voltammetry technique. The reductive reactivity of the nitro-benzene compounds at the copper electrode was evaluated, the reduction mechanisms of the nitrobenzene compounds at the copper electrode and the influences of pH on them were also discussed in this paper. The experimental results show that nitro-benzene compounds is capable of reducing directly at the copper electrode, and the reduction peaks were at - 0.58V and - 1.32V or so (vs. SCE). Both acidity and basicity favor reduction of nitro-group at the copper electrode: the elimination reaction is easy to occur in the alkaline medium with the formation of nitroso-group; in the acid medium the probability of the reaction between the obtained electrons nitro group and hydrogen ions raises, which causes magnification of the current through the solution; in addition, the growth of hydrogen atoms in number favors the occurring of the addition and substitution reactions at the electrode. pH strongly influenced the electrochemical reduction characteristics of the nitrobenzene compounds at the copper electrode, and it mainly depends on the properties of the substituents on the benzene ring, their configurations and numbers, and their location versus nitro group on the benzene ring. The results provide a theoretical and experimental basis for investigating the reduction mechanisms by the catalyzed iron inner electrolysis process.

  9. Preparation, characterization, and photocatalytic performance of Ce2S3 for nitrobenzene reduction

    Science.gov (United States)

    Chen, Shifu; Zhang, Huaye; Fu, Xianliang; Hu, Yingfei

    2013-06-01

    Ce2S3 photocatalysts were synthesized by a co-precipitation method using cerium nitrate and thioacetamide as raw materials. The samples were characterized by X-ray powder diffraction analysis, UV-visible diffuse reflectance spectroscopy, scanning electron microscopy, and differential thermal analysis. Photocatalytic reduction of nitrobenzene (NB) under UV or visible light illumination was used to evaluate the photocatalytic activity of the Ce2S3 samples. The result indicated that the sample prepared at 300 °C for 12 h exhibited the highest activity. For 140 mL 8.13 × 10-4 mol/L of NB in methanol solvent, after illumination for 5 h, about 43.9% and 34.7% of NB were reduced to aniline over the sample under UV and visible light irradiation, respectively. The effects of the catalyst amount, illumination time, and sorts of solvent on the photocatalytic performance were investigated specifically. The reduction process of NB over Ce2S3 was finally discussed.

  10. Synthesis of nanoscale zero-valent iron/ordered mesoporous carbon for adsorption and synergistic reduction of nitrobenzene.

    Science.gov (United States)

    Ling, Xiaofeng; Li, Jiansheng; Zhu, Wen; Zhu, Yaoyao; Sun, Xiuyun; Shen, Jinyou; Han, Weiqing; Wang, Lianjun

    2012-05-01

    Nanoscale zero-valent iron (NZVI) supported on ordered mesoporous carbon (OMC) was synthesized through liquid phase reduction route. The NZVI/OMC composite was characterized by X-ray diffraction, N(2) adsorption/desorption and transmission electron microscopy. Results reveal that the composite possesses ordered mesostructure with NZVI distributing homogeneously on the surface of OMC support. The removal effects of nitrobenzene (NB) in water with OMC, NZVI/OMC and non-supported NZVI were evaluated. Results indicate that NZVI/OMC shows enhanced removal efficiency, which is attributed to its adsorption and synergistic reduction for NB. The transformation process of NB was further investigated by HPLC. Nitrosobenzene and phenylhydroxylamine were detected as intermediate products and aniline was the final reductive product.

  11. Fabrication of silver nanoparticles in pH responsive polymer microgel dispersion for catalytic reduction of nitrobenzene in aqueous medium

    Science.gov (United States)

    Farooqi, Zahoor H.; Begum, Robina; Naseem, Khalida; Rubab, Uma; Usman, Muhammad; Khan, Abbas; Ijaz, Aysha

    2016-12-01

    Copolymer microgels based on N-isopropylacrylamide (NIPAM) and methacrylic acid (MAA) have been synthesized by free radical emulsion polymerization using N, N-methylenebisacrylamide (BIS) as a cross-linker. Synthesized microgels were characterized by Fourier transform infrared spectroscopy (FTIR). Then silver nanoparticles were fabricated in the synthesized microgels by in-situ reduction of AgNO3 with NaBH4. The formation of silver nanoparticles was confirmed by UV-Vis spectroscopy. The pH sensitivity of the copolymer microgels was investigated using dynamic light scattering technique (DLS). Hydrodynamic radius of P (NIPAM-MAA) microgels increases with increase in pH of the medium at 25°C. Surface plasmon resonance wavelength (λSPR) of silver nanoparticles increases with increase in hydrodynamic radius due to change in pH of the medium. The catalytic activity for the reduction of nitrobenzene (NB), an environmental pollutant, into aniline was investigated by UV-Vis spectroscopy in excess of NaBH4 using hybrid microgels as catalyst. The value of apparent rate constant ( k app) of the reaction was calculated using pseudo first order kinetic model and it was found to be linearly related to the amount of catalyst. The results were compared with literature data. The system was found to be an effective catalyst for conversion of NB into aniline.

  12. 碳材料催化硝基苯还原反应%Reduction of nitrobenzene catalyzed by carbon materials

    Institute of Scientific and Technical Information of China (English)

    吴树昌; 温国栋; 钟炳伟; 张炳森; 谷献模; 王宁; 苏党生

    2014-01-01

    The reduction of nitrobenzene catalyzed by different carbon materials (mainly carbon nanotubes) was studied. TGA, TPD, TEM, N2 adsorption-desorption, and Raman spectroscopy were used to show that it was oxygenated groups that gave catalytic activity, while the surface area, pore struc-ture, morphology, structural defects and Fe impurities in the catalysts did not have a significant influence on the activity. The carbonyl group played an important role, but the carboxylic group and anhydride adversely affected the reaction. The conjugated π system, which was necessary for elec-tron transfer and nitrobenzene adsorption, was another critical factor. The reaction proceeded through the direct route in which the intermediate nitrosobenzene was converted directly to aniline quickly.%本文对碳材料(主要是碳纳米管)催化硝基苯的还原反应进行了系统研究。通过热重分析、程序升温脱附、透射电子显微镜、物理吸附以及拉曼光谱等表征,发现碳材料表面的含氧官能团在反应中起着重要的作用,而比表面、孔结构、形貌、结构缺陷以及可能存在的铁杂质对反应没有显著影响。羰基的作用非常重要,但是羧基和酸酐对反应不利。除此之外,材料的π电子体系也很关键,因为它可以传递电子,并且利于硝基苯的吸附。硝基苯还原按照直接路径进行,反应过程中生成的中间体亚硝基苯可以迅速转化为苯胺。

  13. A membrane-free, continuously feeding, single chamber up-flow biocatalyzed electrolysis reactor for nitrobenzene reduction.

    Science.gov (United States)

    Wang, Ai-Jie; Cui, Dan; Cheng, Hao-Yi; Guo, Yu-Qi; Kong, Fan-Ying; Ren, Nan-Qi; Wu, Wei-Min

    2012-01-15

    A new bioelectrochemical system (BES), a membrane-free, continuous feeding up-flow biocatalyzed electrolysis reactor (UBER) was developed to reduce oxidative toxic chemicals to less- or non-toxic reduced form in cathode zone with oxidation of electron donor in anode zone. Influent was fed from the bottom of UBER and passed through cathode zone and then anode zone. External power source (0.5 V) was provided between anode and cathode to enhance electrochemical reactions. Granular graphite and carbon brush were used as cathode and anode, respectively. This system was tested for the reduction of nitrobenzene (NB) using acetate as electron donor and carbon source. The influent contained NB (50-200 mg L(-1)) and acetate (1000 mg L(-1)). NB was removed by up to 98% mainly in cathode zone. The anode potential maintained under -480 mV. The maximum NB removal rate was up to 3.5 mol m(-3) TV d(-1) (TV=total empty volume) and the maximum aniline (AN) formation rate was 3.06 mol m(-3) TV d(-1). Additional energy required was less than 0.075 kWh mol(-1)NB. The molar ratio of NB removed vs acetate consumed varied from 4.3 ± 0.4 to 2.3 ± 0.1 mol mol(-1). Higher influent phosphate or acetate concentration helped NB removal rate. NB could be efficiently reduced to AN as the power supplied of 0.3 V.

  14. Preparation of aniline from photocatalytic reduction of nitrobenzene using Pt/Nd{sub 2}O{sub 3} nanocomposite

    Energy Technology Data Exchange (ETDEWEB)

    Mohamed, R.M., E-mail: mhmdouf@gmail.com

    2015-11-05

    In this manuscript, a template method was used to synthesis Pt-doped Nd{sub 2}O{sub 3} nanostructures with controlled Pt doping contents. The characterizations illustrated that the obtained samples have ultra high surface area (190 m{sup 2}/g), high crystallinity, small grain size (20 nm) and hollow spherical like morphology. Also, the band gap of the Pt-doped Nd{sub 2}O{sub 3} nanostructures can be controlled by controlling the Pt contents. The photocatalytic activity of the Pt-doped Nd{sub 2}O{sub 3} nanostructures samples was studied by studying the reduction of nitrobenzene into aniline using visible light irradiation. The photocatalytic performance of Nd{sub 2}O{sub 3} was enhanced by Pt doping. This can be attributed to the fact that the trapping effect of the Pt-doped Nd{sub 2}O{sub 3} nanostructures and the red shift of absorption edge. The study result provides an effective method to create different photocatalysts with enhanced visible-light-driven photocatalytic performance. - Highlights: • Pt-doped Nd{sub 2}O{sub 3} hollow sphere was prepared by a template method. • Photocatalytic preparation of aniline under visible light was dependent on wt % of Pt. • Catalyst re-use revealed the present photocatalyst remain effective and active after five cycles.

  15. Probing the Role of Promoters in Zinc Reduction of Nitrobenzene: Continuous Production of Hydroxylaminobenzene [PREPRINT

    Science.gov (United States)

    2006-10-30

    can be achieved at a reaction temperature of 250oC (Boix and Poliakoff , 1999). It is postulated that the reaction of Zn with high-temperature...06) 12 Boix, C.; Poliakoff , M. Selective Reductions of Nitroarenes to Anilines using Metallic Zinc in Near-Critical Water. J. Chem. Soc., Perkin

  16. Synthesis of highly stable, water-dispersible copper nanoparticles as catalysts for nitrobenzene reduction.

    Science.gov (United States)

    Kaur, Ravneet; Giordano, Cristina; Gradzielski, Michael; Mehta, Surinder K

    2014-01-01

    We report an aqueous-phase synthetic route to copper nanoparticles (CuNPs) using a copper-surfactant complex and tests of their catalytic efficiency for a simple nitrophenol reduction reaction under atmospheric conditions. Highly stable, water-dispersed CuNPs were obtained with the aid of polyacrylic acid (PAA), but not with other dispersants like surfactants or polymethacrylic acid (PMAA). The diameter of the CuNPs could be controlled in the range of approximately 30-85 nm by modifying the ratio of the metal precursor to PAA. The catalytic reduction of p-nitrophenol to p-aminophenol takes place at the surface of CuNPs at room temperature and was accurately monitored by UV/Vis spectroscopy. The catalytic efficiency was found to be remarkably high for these PAA-capped CuNPs, given the fact that at the same time PAA is efficiently preventing their oxidation as well. The activity was found to increase as the size of the CuNPs decreased. It can therefore be concluded that the synthesized CuNPs are catalytically highly efficient in spite of the presence of a protective PAA coating, which provides them with a long shelf life and thereby enhances the application potential of these CuNPs. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Bioreduction of nitrobenzene, natural organic matter, and hematite by Shewanella putrefaciens CN32.

    Science.gov (United States)

    Luan, Fubo; Burgos, William D; Xie, Li; Zhou, Qi

    2010-01-01

    We examined the reduction of nitrobenzene by Shewanella putrefaciens CN32 in the presence of natural organic matter (NOM) and hematite. Bioreduction experiments were conducted with combinations and varied concentrations of nitrobenzene, soil humic acid, Georgetown NOM, hematite, and CN32. Abiotic experiments were conducted to quantify nitrobenzene reduction by biogenic Fe(II) and by bioreduced NOMs. We show that S. putrefaciens CN32 can directly reduce nitrobenzene. Both NOMs enhanced nitrobenzene reduction and the degree of enhancement depended on properties of the NOMs (aromaticity, organic radical content). Hematite enhanced nitrobenzene reduction by indirect reaction with biogenic-Fe(II), however, enhancement was dependent on the availability of excess electron donor. Under electron donor-limiting conditions, reducing equivalents diverted to hematite were not all transferred to nitrobenzene. In systems that contained both NOM and hematite we conclude that NOM-mediated reduction of nitrobenzene was more important than Fe(II)-mediated reduction.

  18. Water as a Direct Hydrogen Donor in Supercritical Carbon Di-oxide: A Novel and Efficient Zn-H2O-CO2 System for Chemo selective Reduction of Nitrobenzenes to Anilines

    Institute of Scientific and Technical Information of China (English)

    JIANG Huan-Feng; DONG Yao-Sen

    2008-01-01

    An eco-friendly and cheap Zn-H2O-CO2 system was presented for chemoselective reduction of nitrobenzenes to anilines with high yields (80%-97% isolated yields) in supercritical carbon dioxide. This process brings together the very important green chemistry technologies--the use of carbon dioxide as a solvent and the use of water as a hydrogen donor.

  19. Shock compression of nitrobenzene

    Science.gov (United States)

    Kozu, Naoshi; Arai, Mitsuru; Tamura, Masamitsu; Fujihisa, Hiroshi; Aoki, Katsutoshi; Yoshida, Masatake; Kondo, Ken-Ichi

    1999-06-01

    The Hugoniot (4 - 30 GPa) and the isotherm (1 - 7 GPa) of nitrobenzene have been investigated by shock and static compression experiments. Nitrobenzene has the most basic structure of nitro aromatic compounds, which are widely used as energetic materials, but nitrobenzene has been considered not to explode in spite of the fact its calculated heat of detonation is similar to TNT, about 1 kcal/g. Explosive plane-wave generators and diamond anvil cell were used for shock and static compression, respectively. The obtained Hugoniot consists of two linear lines, and the kink exists around 10 GPa. The upper line agrees well with the Hugoniot of detonation products calculated by KHT code, so it is expected that nitrobenzene detonates in that area. Nitrobenzene solidifies under 1 GPa of static compression, and the isotherm of solid nitrobenzene was obtained by X-ray diffraction technique. Comparing the Hugoniot and the isotherm, nitrobenzene is in liquid phase under experimented shock condition. From the expected phase diagram, shocked nitrobenzene seems to remain metastable liquid in solid phase region on that diagram.

  20. Effect of Mole Percentage of Crosslinker of Silver-poly(N-isopropylacrylamide-co-acrylic acid Hybrid Microgels on Catalytic Reduction of Nitrobenzene

    Directory of Open Access Journals (Sweden)

    Zahoor H. FAROOQI

    2015-02-01

    Full Text Available Poly(N-isopropylacrylamide-co-acrylic acid microgels [P(NIPAM-co-AAc] with 2, 4, 6 and 8 mole percentage of N,N-methylene-bis-acrylamide were used as micro-reactors for the fabrication of Ag nanoparticles using the in situ reduction method. The pure and hybrid microgels were characterized by Fourier transform infrared and Ultraviolet-Visible spectroscopies. Silver-poly(N-isopropylacrylamide-co-acrylic acid hybrid microgels [Ag-P(NIPAM-co-AAc] with different crosslinker contents were used as catalysts for reduction of nitrobenzene (NB in aqueous medium in order to investigate the effect of crosslinker content on the value of apparent rate constant (kapp. 0.041, 0.146, 0.2388 and 0.255 min-1 were found as values of kapp for catalytic reduction of NB using hybrid microgels with 2, 4, 6 and 8 mole percentage of crosslinker, respectively. The effect of crosslinker feed content of hybrid microgels on catalytic activity for reduction of NB was compared to that of reduction of p-nitrophenol in aqueous medium.

  1. Preparation of FeO(OH Modified with Polyethylene Glycol and Its Catalytic Activity on the Reduction of Nitrobenzene with Hydrazine Hydrate

    Directory of Open Access Journals (Sweden)

    Ke Ying Cai

    2016-10-01

    Full Text Available Iron oxyhydroxide was prepared by dropping ammonia water to Fe(NO33.9H2O dispersed in polyethylene glycol (PEG 1000. The catalyst was characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy and laser particle size analyzer. The results showed the catalyst modified with polyethylene glycol was amorphous. The addition of PEG during the preparation make the particle size of the catalyst was smaller and more uniform. The catalytic performance was tested in the reduction of nitroarenes to corresponding amines with hydrazine hydrate, and the catalyst showed excellent activity and stability. Copyright © 2016 BCREC GROUP. All rights reserved Received: 2nd February 2016; Revised: 26th April 2016; Accepted: 7th June 2016 How to Cite: Cai, K.Y., Liu, Y.S., Song, M., Zhou, Y.M., Liu, Q., Wang, X.H. (2016. Preparation of FeO(OH Modified with Polyethylene Glycol and Its Catalytic Activity on the Reduction of Nitrobenzene with Hydrazine Hydrate. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (3: 363-368 (doi:10.9767/bcrec.11.3.576.363-368 Permalink/DOI: http://doi.org/10.9767/bcrec.11.3.576.363-368

  2. Characterisation of "Catalão" and "Salsichão" Portuguese traditional sausages with salt reduction.

    Science.gov (United States)

    Laranjo, Marta; Gomes, Ana; Agulheiro-Santos, Ana Cristina; Potes, Maria Eduarda; Cabrita, Maria João; Garcia, Raquel; Rocha, João Miguel; Roseiro, Luísa Cristina; Fernandes, Maria José; Fernandes, Maria Helena; Fraqueza, Maria João; Elias, Miguel

    2016-06-01

    The present study evaluated the effect of salt reduction on traditional dry-cured sausages' safety, quality and product acceptance, comprising physicochemical and microbiological parameters, biogenic amines, fatty acids, texture profile and sensory analysis. According to our results, salt content had a major effect on microbiological counts, although not compromising the products' safety. Marked differences were identified regarding biogenic amines, in particular for histamine, tyramine and cadaverine, which were detected in larger amounts in products with 3%. Moreover, significant differences in the fatty acids profile have also been found, but only in less abundant components such as linoleic, lauric and heneicosanoic acids. Texture profile analysis of low-salt products, revealed a decrease in hardness and chewiness, along with an increase in adhesiveness values. Sensory evaluations revealed that despite the less intense aroma, products with 3% salt, had a more balanced salt perception. Our results suggest that salt content may be reduced to 50% in dry-cured products, with the obvious health-related advantages.

  3. Methaemoglobinemia in nitrobenzene poisoning.

    Directory of Open Access Journals (Sweden)

    Chongtham D

    1997-07-01

    Full Text Available A young girl with nitrobenzene induced methaemoglobinaemia was saved by the timely use of mechanical ventilator, administration of oral methylene blue and parenteral ascorbic acid. Though parenteral methylene blue is the antidote of choice, due to its non-availability, the laboratory preparation of methylene blue have been utilized orally. The rare occurrence of such cases, and the efficacy of oral methylene blue and other supportive measures in evading death due to Nitrobenzene poisoning have been highlighted.

  4. Continuous preparation of nanoscale zero-valent iron using impinging stream-rotating packed bed reactor and their application in reduction of nitrobenzene

    Science.gov (United States)

    Jiao, Weizhou; Qin, Yuejiao; Luo, Shuai; Feng, Zhirong; Liu, Youzhi

    2017-02-01

    Nanoscale zero-valent iron (nZVI) was continuously prepared by high-gravity reaction precipitation through a novel impinging stream-rotating packed bed (IS-RPB). Reactant solutions of FeSO4 and NaBH4 were conducted into the IS-RPB with flow rates of 60 L/h and rotating speed of 1000 r/min for the preparation of nZVI. As-prepared nZVI obtained by IS-RPB were quasi-spherical morphology and almost uniformly distributed with a particle size of 10-20 nm. The reactivity of nZVI was estimated by the degradation of 100 ml nitrobenzene (NB) with initial concentration of 250 mg/L. The optimum dosage of nZVI obtained by IS-RPB was 4.0 g/L as the NB could be completely removed within 10 min, which reduced 20% compared with nZVI obtained by stirred tank reactor (STR). The reduction of NB and production of aniline (AN) followed pseudo-first-order kinetics, and the pseudo-first-order rate constants were 0.0147 and 0.0034 s-1, respectively. Furthermore, the as-prepared nZVI using IS-RPB reactor in this work can be used within a relatively wide range pH of 1-9.

  5. A Pollutant Transformation Laboratory Exercise for Environmental Chemistry: The Reduction of Nitrobenzenes by Anaerobic Solutions of Humic Acid

    Science.gov (United States)

    Dunnivant, Frank M.; Reynolds, Mark-Cody

    2007-01-01

    The laboratory experiment, which acts as a capstone, integrated lecture-laboratory exercise involving solution preparation, pH buffers, [E[subscript]H] (reduction potential) buffers, organic reaction mechanisms, reaction kinetics, and instrumental analysis is presented. The students completing the lecture and laboratory exercises could gain a…

  6. Enhanced biotransformation of nitrobenzene by the synergies of Shewanella species and mediator-functionalized polyurethane foam.

    Science.gov (United States)

    Wang, Jing; Lu, Hong; Zhou, Yan; Song, Yang; Liu, Guangfei; Feng, Yujie

    2013-05-15

    The performance and mechanism of anaerobic treatment of nitrobenzene using the combination of Shewanella species and anthraquinone-2-sulfonate-modified polyurethane foam (Shewanella/AQS-PUF) were investigated. The results showed that Shewanella/AQS-PUF significantly accelerated nitrobenzene bio-reduction (95.6%) and aniline formation (94.3%) with nitrobenzene removal rate up to 0.13 mM h(-1). Moreover, there were synergistic effects between Shewanella species and AQS-PUF on promoting nitrobenzene biotransformation with 5-fold increase in first-order rate constant compared to that without AQS-PUF. During this process, AQS-PUF could induce Shewanella species to secrete more flavins (0.335 μM) as redox mediator for nitrobenzene bio-reduction. Meanwhile, it was also found that the bound EPS of Shewanella species could act as biocatalyst for nitrobenzene reduction and the addition of flavins enhanced its catalytic activity. This indicated that the EPS of Shewanella species was not only involved in direct bio-reduction of nitrobenzene, but also interacted with secreted flavins to mediate nitrobenzene bio-reduction.

  7. Study on degradation of nitrobenzene in groundwater using emulsified nano-zero-valent iron

    Science.gov (United States)

    Dong, Jun; Wen, Chunyu; Liu, Dengfeng; Zhang, Wenjing; Li, Jintong; Jiang, Hanjie; Qin, Chongwei; Hong, Mei

    2015-01-01

    Emulsified nano-zero-valent iron (EZVI) is a modified form of bare nanoiron with improved transportability and targetability for the remediation of organic-solvents polluted soil and groundwater. In this work, EZVI (50-150 nm) was prepared by coating an emulsified vegetable oil membrane on the surface of Fe nanoparticles. EZVI was well-dispersed and less aggregation was observed. Batch experiments were conducted in anaerobic conditions to investigate the kinetics of nitrobenzene reduction by EZVI and the influences of oil concentration, initial iron content, and initial pH. Results indicated that the kinetics of nitrobenzene reduction by EZVI followed a pseudo-first-order kinetics. The observed rate constant of nitrobenzene is 0.0942 min-1. The oil concentration of 1 and 2 % tended to be preferred concentrations. The rate of nitrobenzene degradation and aniline formation increased with increasing iron content. The low pH is favorable to the nitrobenzene reduction by EZVI.

  8. Iron(III)-bearing clay minerals enhance bioreduction of nitrobenzene by Shewanella putrefaciens CN32.

    Science.gov (United States)

    Luan, Fubo; Liu, Yan; Griffin, Aron M; Gorski, Christopher A; Burgos, William D

    2015-02-03

    Iron-bearing clay minerals are ubiquitous in the environment, and the clay-Fe(II)/Fe(III) redox couple plays important roles in abiotic reduction of several classes of environmental contaminants. We investigated the role of Fe-bearing clay minerals on the bioreduction of nitrobenzene. In experiments with Shewanella putrefaciens CN32 and excess electron donor, we found that the Fe-bearing clay minerals montmorillonite SWy-2 and nontronite NAu-2 enhanced nitrobenzene bioreduction. On short time scales (<50 h), nitrobenzene reduction was primarily biologically driven, but at later time points, nitrobenzene reduction by biologically formed structural Fe(II) in the clay minerals became increasingly important. We found that chemically reduced (dithionite) iron-bearing clay minerals reduced nitrobenzene more rapidly than biologically reduced iron-bearing clay minerals despite the minerals having similar structural Fe(II) concentrations. We also found that chemically reduced NAu-2 reduced nitrobenzene faster as compared to chemically reduced SWy-2. The different reactivity of SWy-2 versus NAu-2 toward nitrobenzene was caused by different forms of structural clay-Fe(II) in the clay minerals and different reduction potentials (Eh) of the clay minerals. Because most contaminated aquifers become reduced via biological activity, the reactivity of biogenic clay-Fe(II) toward reducible contaminants is particularly important.

  9. El perfectum praesens en català

    Directory of Open Access Journals (Sweden)

    Mitja Skubic

    2004-12-01

    Full Text Available Examinar els valors dels paradigmes verbals en les llengües romàniques és sempre atraient, sobretot pel que fa refere`ncia als de l’esfera del passat. En aquest breu article volem aportar una nota breu sobre els valors dels paradigmes de prete`rit del verb en català a partir d’alguns textos en aquesta llengua tenint en compte, alhora, els diferents estudis que analitzen aquest problema, així també com les gramàtiques del català contemporani i d’`epoques anteriors1.

  10. Palladium nanoclusters entrapped in polyurea:A recyclable and efficient catalyst for reduction of nitro-benzenes and hydrodechlorination of halogeno-benzenes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Polyurea-entrapped palladium nanoclusters have been prepared by interfacial polymerization in W/O emulsion and showed high thermal stability and chemical stability with the content of 0.12 mmol g-1 Pd.This catalyst exhibited dual catalytic activity for reduction of nitro compounds and hydrodehalogenation of aromatic chlorides in atmospheric hydrogen with 100% yield for reduction of nitro compounds and >99% yield for hydrodehalogenation of aromatic chlorides.This immobilizing method was particularly effective and eliminated the need of special chelating groups.

  11. Síntese e emprego do ciclometalado [Pd(dmba(N3(PPh3] em processos catalíticos envolvendo a n-carbonilação redutiva de nitroarenos a carbamatos e na síntese de derivados da uréia Synthesis of [Pd(dmba(N3(PPh3] and its use in catalytic processes involving the reductive n-carbonylation of nitroarenes to carbamates and in the synthesis of urea derivatives

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Fávero Caires

    2006-07-01

    Full Text Available This work deals with the use of the cyclometallated compound [Pd(dmba(N3(PPh3] in homogeneous catalytic processes comprising the reductive N-carbonylation of nitrobenzene and p-nitrotoluene to ethyl-phenylcarbamate and ethyl-4-methylphenylcarbamate, respectively. The cyclopalladated compound was also employed in the synthesis of urea derivatives by reacting p-nitrotoluene and m-nitrotoluene, respectively, with p-toluidine and and m-chloroaniline.

  12. Liquid Phase Hydrogenation of Nitrobenzene over Nickel Supported on Titania

    Institute of Scientific and Technical Information of China (English)

    K.Joseph Antony RAJ; M.G.PRAKASH; R.MAHALAKSHMY; T.ELANGOVAN; B.VISWANATHAN

    2012-01-01

    The catalytic hydrogenation of nitrobenzene to aniline employing nickel impregnated on rutile,anatase,and high surface area titania supports has been investigated.The nickel is present in elemental state as fcc phase on the catalyst as evidenced by X-ray diffraction results.The Ni crystallite size was found to be greater for Ni/anatase.The temperature-programmed reduction results suggest a greater metal-support interaction for Ni/rutile.The observed order of catalytic activity for the hydrogenation of nitrobenzene is Ni/rutile > Ni/anatase > Ni/TiO2.A conversion of 99% was observed for Ni/rutile at 140 ℃ and hydrogen pressure of 1.96 MPa.Interestingly,aniline is the only product formed which demonstrates the catalytic hydrogenation of nitrobenzene proceeds with atom economy.Both Ni/rutile and Ni/anatase exhibited a better stability than Ni/TiO2.The hydrogenation proceeds with the preferential adsorption of hydrogen on nickel present in the catalyst surface,possibly assisted by TiOx species.

  13. 77 FR 47114 - Manufacturer of Controlled Substances; Notice of Registration; Catalent Pharma Solutions, Inc.

    Science.gov (United States)

    2012-08-07

    ... Enforcement Administration Manufacturer of Controlled Substances; Notice of Registration; Catalent Pharma... FR 24984, Catalent Pharma Solutions, Inc., 10381 Decatur Road, Philadelphia, Pennsylvania 19114, made... Catalent Pharma Solutions, Inc. to import the basic class of controlled substance is consistent with...

  14. The Effect of Temperature on the Production of Nitrobenzene

    Science.gov (United States)

    Agustriyanto, R.; Sapei, L.; Rosaline, G.; Setiawan, R.

    2017-02-01

    Nitrobenzene is a compound derived from benzene and quite fundamental in the petrochemical industry. One of which is in the manufacture of aniline. Aniline has an important role as dyes, synthetic rubber materials, rocket fuels and pharmaceuticals. Nitrobenzene can be synthesized by the nitration reaction of benzene. The purpose of the research is to design synthesis process of nitrobenzene by using Aspen Hysys simulator. The effect of changes in operating condition on nitrobenzene will be investigated. The benefits of the research are to obtain the optimum operating temperature for nitrobenzene production so that the use of utility can be minimized.

  15. Simone de Beauvoir en català

    OpenAIRE

    Godayol, Pilar

    2013-01-01

    Simone de Beauvoir fut avec Betty Friedan une des premières théoriciennes du féminisme à arriver en Catalogne dans les années soixante. Cet article rapporte la réception de Simone de Beauvoir en catalan et plus particulièrement l’influence exercée par Le deuxième sexe. Con Betty Friedan, Simone de Beauvoir fue una de las primeras pensadoras feministas que llegaron a Cataluña en los años sesenta. Este artículo da cuenta de la recepción al catalán de Simone de Beauvoir y se fija especialment...

  16. Positron annihilation studies on Amberlite XAD-4 adsorbed with nitrobenzene

    Science.gov (United States)

    Sudarshan, K.; Pujari, P. K.; Goswami, A.

    2006-11-01

    XAD-4 resin was loaded with various amounts of nitrobenzene which is known to be a strong chemical quencher of positronium. The positron annihilation lifetime studies showed a continuous decrease in the o-Ps intensity with increasing nitrobenzene loading. No appreciable change in the o-Ps lifetime was observed. This suggests that the nitrobenzene acts as inhibitor rather than quencher in the current case. Possible reasons for the manifestations of such powerful quencher as an inhibitor are discussed.

  17. Biotransformation of nitrobenzene by bacteria containing toluene degradative pathways

    Energy Technology Data Exchange (ETDEWEB)

    Haigler, B.E.; Spain, J.C. (Air Force Civil Engineering Support Agency, Tyndall AFB, FL (United States))

    1991-11-01

    Nonpolar nitroaromatic compounds have been considered resistant to attack by oxygenases because of the electron withdrawing properties of the nitro group. The authors have investigate the ability of seven bacterial strains containing toluene degradative pathways to oxidize nitrobenzene. Cultures were induced with toluene vapor prior to incubation with nitrobenzene, and products were identified by high-performance liquid chromatography and gas chromatography-mass spectrometry. Pseudomonas cepacia G4 and a strain of Pseudomonas harboring the TOL plasmid (pTN2) did not transform nitrobenzene. Cells of Pseudomonas putida F1 and Pseudomonas sp. strain JS150 converted nitrobenzene to 3-nitrocatechol. Transformation of nitrobenzene in the presence of {sup 18}O{sub 2} indicated that the reaction in JS150 involved the incorporation of both atoms of oxygen in the 3-nitrocatechol, which suggests a dioxygenase mechanism. P. putida 39/D, a mutant strain of P. putida F1, converted nitrobenzene to a compound tentatively identified as cis-1, 2-dihydroxy-3-nitrocyclohexa-3, 5-diene. This compound was rapidly converted to 3-nitrocatechol by cells of strain JS150. Cultures of Pseudomonas mendocina KR-1 converted nitrobenzene to a mixture of 3- and 4-nitrophenol (10 and 63%, respectively). Pseudomonas pickettii PKO1 converted nitrobenzene to 3- and 4-nitrocatechol via 3- and 4-nitrophenol. The nitrocatechols were slowly degraded to unidentified metabolites. Nitrobenzene did not serve as an inducer for the enzymes that catalyzed its oxidation.

  18. Quantitative structure-activity relationships for the toxicity and bioconcentration factor of nitrobenzene derivatives towards the guppy (Poecilia reticulata)

    NARCIS (Netherlands)

    Deneer, J.W.; Sinnige, T.L.; Seinen, W.; Hermens, J.L.M.

    1987-01-01

    The acute toxicity and bioconcentration factor of a series of nitrobenzene derivatives was determined for the guppy. Toxicity is found to be determined by both hydrophobicity (expressed by the octanol/water partition coefficient) and rate of reduction of the nitro group (expressed by either electroc

  19. 78 FR 69131 - Importer of Controlled Substances; Notice of Registration; Catalent CTS, LLC

    Science.gov (United States)

    2013-11-18

    ... Enforcement Administration Importer of Controlled Substances; Notice of Registration; Catalent CTS, LLC By..., Catalent CTS, LLC., 10245 Hickman Mills Drive, Kansas City, Missouri 64137, made application to the Drug...) and 952(a) and determined that the registration of Catalent CTS, LLC., to import the basic classes...

  20. 78 FR 39338 - Importer of Controlled Substances; Notice of Registration; Catalent CTS., Inc.

    Science.gov (United States)

    2013-07-01

    ...; Notice of Registration; Catalent CTS., Inc. By Notice dated April 10, 2013, and published in the Federal Register on April 19, 2013, 78 FR 23594, Catalent CTS., Inc., 10245 Hickman Mills Drive, Kansas City... U.S.C. 823(a) and 952(a) and determined that the registration of Catalent CTS., Inc., to import...

  1. Development of aquatic life criteria for nitrobenzene in China.

    Science.gov (United States)

    Yan, Zhen-guang; Zhang, Zhi-sheng; Wang, Hong; Liang, Feng; Li, Ji; Liu, Hong-ling; Sun, Cheng; Liang, Li-jun; Liu, Zheng-tao

    2012-03-01

    Nitrobenzene is a toxic pollutant and was the main compound involved in the Songhuajiang accident in 2007, one of the largest water pollution accidents in China in the last decade. No aquatic life criteria for nitrobenzene have previously been proposed. In this study, published toxicity data of nitrobenzene to Chinese aquatic species were gathered, and six resident Chinese aquatic organisms were used in toxicity tests to supplement the existing toxicity data for nitrobenzene. Seventeen genuses mean acute values, three genuses mean chronic values to freshwater aquatic animals, and six genus toxicity values to aquatic plants were collected in total. A criterion maximum concentration of 0.018 mg/L and a criterion continuous concentration of 0.001 mg/L were developed based on these data, according to the U.S. Environmental Protection Agency guidelines. These criteria may be useful in the determination of water quality standard of nitrobenzene. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Abiotic reduction of nitroaromatic compounds by Fe(II) associated with iron oxides and humic acid.

    Science.gov (United States)

    Luan, Fubo; Xie, Li; Li, Jun; Zhou, Qi

    2013-05-01

    Experiments were conducted to examine the reduction of nitroaromatic compounds (NACs) by Fe(II) associated with iron oxides (goethite, hematite and magnetite) and humic acid. The reduction rate of nitrobenzene decreased in the order of Fe(II) associated with magnetite>Fe(II) associated with goethite>Fe(II) associated with hematite. We proposed a four-step model (adsorption, electron transfer to conduction band, electron transfer to nitrobenzene and electron transfer to crystal lattice) for nitrobenzene reduction by Fe(II) associated with iron oxides. Fe(II)-humic acid complexes did not present reduction capability of nitrobenzene. Furthermore, Humic acid significantly inhibited nitrobenzene reduction by Fe(II) associated with iron oxides. The inhibitory effect of humic acid toward the reduction of nitrobenzene decreased in the order of magnetite>goethite>hematite. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Acute metheamoglobinemia due to nitrobenzene poisoning: Case series

    Directory of Open Access Journals (Sweden)

    Harish Kumar S, Ujjawal Kumar, Raghavendra Prasad B N, Kiran BJ, Anil Kumar M

    2014-04-01

    Full Text Available Nitrobenzene is a nitrite compound; its toxic effects are due to its ability to convert hemoglobin to methaemoglobin by oxidizing iron. The clinical features of nitrobenzene poisoning vary based on the concentration of methaemoglobin in blood. Immediate identification based on clinical features, odour of the compound with supporting evidence of increased methaemoglobin levels will help in a timely intervention thus preventing fatal outcome. Early haemodynamic and ventilator support along with administration of methylene blue as an antidote has been proved crucial in saving some lives. An acute nitrobenzene poisoning presenting with methaemoglobinemia is becoming quite common in this part of the country. Here authorsreport a series of cases of nitrobenzene poisoning where immediate clinical evaluation, with repeated intravenous methylene blue saved three patients, but two patients presenting late and with heavy exposure could not be saved

  4. Cephalic morphology in the Cavall Pirinenc Català breed

    OpenAIRE

    Pere-Miquel Parés i Casanova

    2009-01-01

    Thirty-five metric parameters were taken on 19 skulls belonging to adult Cavall Pirinenc Català horse breed and were subjected to a Principal Component Analysis. Parameters related with neurocranium width, ventral lengths and those related with ocular orbit are poorly discriminants. On the other hand, parameters related with viscerocranium are strongly discriminant. Our study strengths the importance in using parameters linked to viscerocranium, and frontal length, in equine racial studies on...

  5. Biostimulation-enhanced Biodegradation of Nitrobenzene in Contaminated Groundwater

    Institute of Scientific and Technical Information of China (English)

    AN Yong-lei; ZHANG Lan-ying; LIU Na; ZHANG Lei; GAO Huan-fang

    2012-01-01

    In this study,biostimulation technology was used for bioremediation of nitrobenzene-contaminated groundwater by adding a mixture of lactose and phosphate,peptone,and beef extract.During the process of biostimulation,the remediation effectiveness,microbial dehydrogenase activities and microbial densities were investigated;the varieties of microbial community structure and composition were analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE) technique and the relative abundances of nitrobenzene-degrading gene(nbzA) were determined by fluorescence quantitative real-time PCR(RT-PCR).Findings show that the removal rate of nitrobenzene in groundwater could reach about 60% by biostimulation with lactose and phosphate,70% with peptone and 68% with beef extract.The microbial dehydrogenase activities and microbial densities were all improved obviously via biostimulation.The results of PCR-DGGE show that the microbial diversities were improved,and more than ten kinds of dominant microorganisms were detected after biostimulation.RT-PCR results show that the relative abundances of nbzA gene of microbes in groundwater were increased significantly,which indicated that biostimulation actually enhanced the growth of nitrobenzene-degrading bacteria.Therefore,biostimulation is a cost-effective and feasible bioremediation technique for nitrobenzene-contaminated groundwater.

  6. 78 FR 23594 - Importer of Controlled Substances; Notice of Application; Catalent CTS., Inc.

    Science.gov (United States)

    2013-04-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Drug Enforcement Administration Importer of Controlled Substances; Notice of Application; Catalent CTS., Inc..., Catalent Cts., Inc., 10245 Hickman Mills Drive, Kansas City, Missouri 64137, made application by renewal...

  7. 78 FR 52800 - Importer of Controlled Substances; Notice of Application; Catalent CTS., LLC.

    Science.gov (United States)

    2013-08-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Drug Enforcement Administration Importer of Controlled Substances; Notice of Application; Catalent CTS., LLC..., Catalent CTS., LLC., 10245 Hickman Mills Drive, Kansas City, Missouri 64137, made application to the...

  8. 77 FR 24984 - Importer of Controlled Substances; Notice of Application; Catalent Pharma Solutions, Inc.

    Science.gov (United States)

    2012-04-26

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Drug Enforcement Administration Importer of Controlled Substances; Notice of Application; Catalent Pharma Solutions.... Therefore, in accordance with 21 CFR 1301.34(a), this is notice that on January 5, 2012, Catalent...

  9. One pot synthesis of N-ethylaniline from nitrobenzene and ethanol

    Institute of Scientific and Technical Information of China (English)

    LI XiaoNian; ZHANG JunHua; XIANG YiZhi; MA Lei; ZHANG QunFeng; LU ChunShan; WANG Hong; BAI Ying

    2008-01-01

    A novel method for the one pot synthesis of N-alkyl arylamines from nitro aromatic compounds and alcohols is proposed through the combination of the aqueous-phase reforming of alcohol for hydrogen production, the reduction of nitro aromatic compounds for the synthesis of aromatic amine and the N-alkylation of aromatic amine for the production of N-alkyl arylamine over an identical catalyst under the same conditions of temperature and pressure in a single reactor. In this process, hydrogen gener-ated from the aqueous-phase reforming of alcohols was used in-situ for the hydrogenation of nitro aromatic compounds for aromatic amine synthesis, followed by N-alkylation of aromatic amine with alcohols to form the corresponding N-alkyl arylamines at a low partial pressure of hydrogen. For the system composed of nitrobenzene and ethanol, under the conditions of 413 K and PN2=1 MPa, the conversion degrees of nitrobenzene and aniline were 100%, the selectivity to N-ethylaniline and N, N-diethylaniline were 85.9% and 0%-4%, respectivity, after reaction for 8 h at the volumetric ratio of nitrobenzene: ethanol :water = 10:60: 0. The selectivity for N, N-diethylaniline production is much lower than that through the traditional method. In this process, hydrogen and aromatic amines generated from the aqueous-phase reforming of alcohols and hydrogenation of nitro aromatic compounds, re-spectively, could be promptly removed from the surface of the catalyst due to the occurrence of in-situ hydrogenation and N-alkylation reactions. Thus, this may be a potential approach to increase the se-lectivity to N-alkyl arylamine.

  10. One pot synthesis of N-ethylaniline from nitrobenzene and ethanol

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A novel method for the one pot synthesis of N-alkyl arylamines from nitro aromatic compounds and alcohols is proposed through the combination of the aqueous-phase reforming of alcohol for hydrogen production, the reduction of nitro aromatic compounds for the synthesis of aromatic amine and the N-alkylation of aromatic amine for the production of N-alkyl arylamine over an identical catalyst under the same conditions of temperature and pressure in a single reactor. In this process, hydrogen generated from the aqueous-phase reforming of alcohols was used in-situ for the hydrogenation of nitro aromatic compounds for aromatic amine synthesis, followed by N-alkylation of aromatic amine with alcohols to form the corresponding N-alkyl arylamines at a low partial pressure of hydrogen. For the system composed of nitrobenzene and ethanol, under the conditions of 413 K and PN2 = 1 MPa, the conversion degrees of nitrobenzene and aniline were 100%, the selectivity to N-ethylaniline and N, N-diethylaniline were 85.9% and 0%-4%, respectivity, after reaction for 8 h at the volumetric ratio of nitrobenzene:ethanol:water = 10:60:0. The selectivity for N, N-diethylaniline production is much lower than that through the traditional method. In this process, hydrogen and aromatic amines generated from the aqueous-phase reforming of alcohols and hydrogenation of nitro aromatic compounds, respectively, could be promptly removed from the surface of the catalyst due to the occurrence of in-situ hydrogenation and N-alkylation reactions. Thus, this may be a potential approach to increase the selectivity to N-alkyl arylamine.

  11. Location and PCR analysis of catabolic genes in a novel Streptomyces sp. DUT_AHX capable of degrading nitrobenzene

    Institute of Scientific and Technical Information of China (English)

    AI Haixin; ZHOU Jiti; LV Hong; WANG Jing; GUO Jianbo; LIU Guangfei; QU Yuanyuan

    2008-01-01

    A novel strain of Streptomyces sp. DUT_AHX was isolated from sludge contaminated with nitrobenzene and identified on the basis of physiological and biochemical tests and 16S ribosomal DNA (rDNA) sequence analysis. The optimal degradation conditions were as follows: temperature 30℃, pH 7.0-8.0, shaking speed 150-180 r/min and inocula 10% (V/V). The strain, which possessed a partial reductive pathway with the release of ammonia, was also able to grow on mineral salts basal (MSB) medium plates with 2-aminophenol, phenol, or toluene as the sole carbon source. Furthermore, the enzyme activity tests showed crude extracts of nitrobenzene-grown DUT_AHX contained 2-aminophenol 1,6-dioxygenase activity. The 17-kb plasmid was isolated by the modified alkaline lysis method and was further cured by sodium dodecyl sulphate (SDS) together with 37℃. As a result, the cured derivative strain DUT_AHX-4 lost the 2-aminophenol 1,6-dioxygenase activity. The results suggested that the catabolic genes encoding the nitrobenzene-degrading enzymes were plasmid-associated. Moreover, the plasmid DNA was amplified with degenerate primers by touchdown PCR and an expected size fragment (471 bp) was generated. The Blast results revealed that the gene encoding a 157 amino acid polypeptide was 39% to 76% identical to YHS domain protein. The further examination of the plasmid would demonstrate the molecular basis of nitrobenzene catabolism in Streptomyces, such as regulation and genetic organization of the catabolic genes.

  12. Subchronic toxicological effects of aquatic nitrobenzene on Medaka and Chinese rare minnow

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on the simulative exposure experiments of nitrobenzene to two small experimental fishes, Medaka (Oryzias latipes) and Chinese Rare Minnow (Gobiocypris rarus), it was found that nitrobenzene could decrease in a linear way in the static aquatic system. Both fishes could accumulate dose-related levels of nitrobenzene quickly and eliminate the compound rapidly when they were transferred to clean water. The Chinese rare minnow showed more sensitivity to the acute toxicity exposure of nitrobenzene than Medaka. Typical molecular biomarkers in oxidative defense system including superoxide dismutase (SOD), catalase (CAT) showed the chemical induced alterations. The changes of acetylcholinesterase (AChE) activities indicated that nitrobenzene might affect the normal neural function. Nitrobenzene exposure could also lead to obvious damaging effects on the target organs, such as gill and liver by hitopathological studies.

  13. Adsorption properties of nitrobenzene in wastewater with silica aerogels

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The adsorption properties of nitrobenzene from wastewater by hydrophobic silica aerogels were investigated.The effects of adsorption intensity by pH value,adsorption temperature,adsorption time and the amount of the silica aerogels were studied.The adsorption principle and mechanism of silica aerogels adsorbing nitrobenzene were discussed along with the Freundlich equation.The results showed that the adsorption intensity of the hydrophobic silica aerogels could reach 68.76% at better adsorption conditions of adsorption temperature 25°C,pH value 8.35,the amount of SiO2 aerogels dosage 3.33 g/L,and adsorption time of 30 min,and that the adsorption properties were related to the hydrophobility of aerogels,surface area of organic solution,structure of aerogels.

  14. Degradation of nitrobenzene in wastewater by γ-ray irradiation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shu-juan; FENG Shao-hong; YU Han-qing; LI Qian-rong

    2004-01-01

    The degradation of nitrobenzene(NB) by γ-ray irradiation was studied. The influences of dose rate and initial NB concentration were investigated in details. At a dose rate of 55 Gy/min, the degradation kinetics was pseudo-first-order at NB concentrations from 0.2 mmol/L to 4.0 mmol/L. At an initial NB concentration of 0.8 mmol/L, the degradation of NB at various dose rates also followed pseudo-first-order kinetics. Dissolved oxygen was found to have a positive effect on NB degradation. The degradation products were identified as nitrophenol, nitrosobenzene, and hydroquinone, and so on. Based on the product analysis, possible degradation pathways of nitrobenzene were proposed.

  15. Effect of Nitrobenzene on the Embryo Development of Bighead and Silver Carp

    Institute of Scientific and Technical Information of China (English)

    FANG Jingjie; GUAN Qingzhi; CHEN Weixing; ZHU Lei; FAN Zhaoting

    2008-01-01

    The effect of various concentrations of nitrobenzene on the mortality and abnormality rate of bighead and silver carp embryos were studied to provide reference for the evaluation of the effect of nitrobenzene to aquatic organisms and aquatic environment.The results showed that the development of bighead and silver carp embryos was delayed, the mortality and abnormality rates were raised when the embryos were treated with ≥0.010 mg·L-1 nitrobenzene,and with ≥0.085 mg·L-1 nitrobenzene,the mortality rates showed 100%.

  16. Application of Recycled Zero-Valent Iron Nanoparticle to the Treatment of Wastewater Containing Nitrobenzene

    Directory of Open Access Journals (Sweden)

    Heon Lee

    2015-01-01

    Full Text Available Zero-valent iron (ZVI was synthesized using iron oxide, a byproduct of pickling line at a steel work. ZVI with a mean particle size of 500 nm was synthesized. The reaction activity of the synthesized ZVI was much higher than commercial ZVI. When applied to the decomposition of nitrobenzene (NB, the ZVI particles underwent corrosion and passivation oxide film formation, resulting in particle size decrease. The NB decomposition rate increased with increasing ZVI dosage level and with decreasing pH. The solution pH increased monotonously with increasing reaction duration, whereas the aniline concentration showed a maximum at 50 min. Based on the GC/MS analysis, NB is presumed to be reduced into aniline via reductive intermediates such as azobenzene and azoxybenzene. When combined with a subsequent biological process, the synthesized ZVI will be able to decompose NB in wastewater effectively.

  17. A biotic Fe0-H2O system for nitrobenzene removal from groundwater

    DEFF Research Database (Denmark)

    Wu, Jinhua; Yin, Weizhao; Gu, Jingjing;

    2013-01-01

    Batch experiment was conducted to evaluate the capability of a biotic Fe0-H2O for nitrobenzene (NB) removal from groundwater. In this study, iron dosage was 0.25gL-1 throughout the whole experiment and the Fe0-H2O system was amended with 180mgL-1 VSS of mixed culture. The biotic system was tested...... at low concentrations (50mgL-1 as COD) of organic substrates (e.g., ethanol, glucose and sodium acetate) and different concentrations of sulfate, nitrate and dissolved oxygen. The bio-iron system exhibited higher NB removal rate and more AN production. The increasing order of efficiency of tested......), and nitrate showed more significant suppression on NB removal as compared to sulfate. AN elimination occurred during both sulfate-reducing and nitrate-reducing processes and microorganisms got extra reduction capacity from the degradation of AN to reduce nitrate and sulfate, causing the mineralization of NB...

  18. The effects of flow rate and concentration on nitrobenzene removal in abiotic and biotic zero-valent iron columns

    DEFF Research Database (Denmark)

    Yin, Weizhao; Wu, Jinhua; Huang, Weilin

    2016-01-01

    Abstract This study investigated the effects of varying nitrobenzene (NB) loadings via increasing flow rate or influent NB concentration mode on the removal efficiency in zero-valent iron (ZVI) columns sterilized (abiotic) or preloaded with acclimated microorganisms (biotic). It was shown...... within the porous media and that the optimal loading conditions for overall removal, sequestration, and reduction of NB may be different. Optimal operation conditions should be found for preferred sequestration or transformation (or both) of the target contaminants to meet different goals of groundwater...

  19. Aerobic degradation of nitrobenzene by immobilization of Rhodotorula mucilaginosa in polyurethane foam.

    Science.gov (United States)

    Zheng, Chunli; Zhou, Jiti; Wang, Jing; Qu, Baocheng; Wang, Jing; Lu, Hong; Zhao, Hongxia

    2009-08-30

    Rhodotorula mucilaginosa Z1 capable of degrading nitrobenzene was immobilized in polyurethane foam. The nitrobenzene-degrading capacity of immobilized cells was compared to free cells in batches in shaken culture. Effects of pH and temperature on the nitrobenzene degradation showed that polyurethane-immobilized Z1 had higher tolerances toward acid, alkali, and heat than those of free cells. Kinetic studies revealed that higher concentrations of nitrobenzene were better tolerated and more quickly degraded by polyurethane-immobilized Z1 than by free cells. Moreover, the ability of polyurethane-immobilized Z1 to resist nitrobenzene shock load was enhanced. Experiments on the nitrobenzene degradation in different concentrations of NaCl and in the presence of phenol or aniline demonstrated that polyurethane-immobilized Z1 exhibited higher tolerance toward salinity and toxic chemicals than those of free cells. Immobilization therefore could be a promising method for treating nitrobenzene industrial wastewater. This is the first report on the degradation of nitrobenzene by a polyurethane-immobilized yeast strain.

  20. Degradation of nitrobenzene in aqueous solution by ozone-ceramic honeycomb

    Institute of Scientific and Technical Information of China (English)

    SUN Zhi-zhong; MA Jun; WANG Li-bo; ZHAO Lei

    2005-01-01

    The degradation of nitrobenzene by ceramic-honeycomb catalyzed ozonation was investigated. The results showed that the presence of ceramic honeycombs significantly increased the oxidation rate of nitrobenzene by ozone compared to the case of ozone oxidation alone. In this paper, the effects of various factors on the catalytic oxidation were investigated, such as the amount of catalysts,the ozone dosage, the temperature, the pH value and the presence of tert-butanol. With the addition of tert-butanol the removal of nitrobenzene decreased sharply, which appeared to support that, the degradation of nitrobenzene by ozonation followed a radical type mechanism. The EPR experiments verified that higher nitrobenzene removal rate was attributed to more OH radicals generated in the catalyzed ozonation than ozonation alone.

  1. Study on nitrobenzene ratio in water-ice system under different conditions

    Institute of Scientific and Technical Information of China (English)

    LI ZhiJun; WANG Xin; LI QingShan; XU ShiGuo; XU XiangZhou; BAI Yan

    2008-01-01

    A aeries of ice freezing-thawing experiments are performed under different nitro-benzene concentrations of 1.7, 8, 17, 170, and 1700 μg/L. A special flume, made of stainless steel and glass, is built to simulate the flowing water for the experiments. The ice frozen in cold room has similar crystal structure of natural ice, therefore the behaviors of nitrobenzene in the ice frozen in cold room is also believed to be similar to that in natural ice. The results of the experiments reveal that the freezing rate of ice decreases with the increase of nitrobenzene concentration in water, and that the nitrobenzene ratio in water-ice system becomes higher with the increase of freezing rate. In addition, the nitrobenzene in ice does not move and is only re-leased into water after melt.

  2. [Catalytic ozonation of nitrobenzene in water by acidification-activated red mud].

    Science.gov (United States)

    Kang, Ya-ning; Li, Hua-nan; Xu, Bing-bing; Qi, Fei; Zhao, Lun

    2013-05-01

    Red mud as one kind of aluminum industrial wastes was used as raw material for catalyst preparation. It was activated by acidification in order to enhance its catalytic activity in the system of catalytic ozonation. Furthermore, removal performance and reaction mechanism in degradation of organic pollutants were discussed. Results showed that acid modified red mud had more significant catalytic activity than the raw red mud. The removal efficiency of nitrobenzene by catalytic ozonation with acidified red mud (RM6.0) increased with the increasing ozone concentration. When the ozone concentration was increased from 0.4 mg x L(-1) to 1.7 mg x L(-1), the removal efficiency of nitrobenzene increased from 45% to 92%. There was a consistent effect of water pH on the removal efficiency and the ozone concentration variation. The variation of the removal efficiency depended on the initial water pH. This was because the concentration of OH(-) led to ozone decomposition to generate hydroxyl radicals. The higher water pH value led to the quenching of hydroxyl radicals, resulting in the reduction of catalytic activity of RM6.0. The experimental results of aqueous ozone concentration variation in the presence of RM6.0 and inhibition by hydroxyl radicals indicated that the main reaction mechanism was catalytic ozonation of NB. Firstly, aqueous ozone was absorbed onto the surface of RM6.0, and then the concentrated ozone oxidized NB in water which was with a combination of direct and indirect oxidation. In catalytic reaction, hydroxyl radicals were present, which were generated during the oxidation of NB on the surface of RM6.0.

  3. Green synthesis of gold nanoparticles for trace level detection of a hazardous pollutant (nitrobenzene) causing Methemoglobinaemia

    Energy Technology Data Exchange (ETDEWEB)

    Emmanuel, R. [Post Graduate and Research Department of Chemistry, Thiagarajar College, Madurai 625009, Tamil Nadu (India); Karuppiah, Chelladurai [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei 106, Taiwan, ROC (China); Chen, Shen-Ming, E-mail: smchen78@ms15.hinet.net [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei 106, Taiwan, ROC (China); Palanisamy, Selvakumar [Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, Taipei 106, Taiwan, ROC (China); Padmavathy, S. [Department of Zoology and Microbiology, Thiagarajar College, Madurai 625009, Tamil Nadu (India); Prakash, P., E-mail: kmpprakash@gmail.com [Post Graduate and Research Department of Chemistry, Thiagarajar College, Madurai 625009, Tamil Nadu (India)

    2014-08-30

    Graphical abstract: Schematic representation for green synthesis of Au-NPs and its electroreduction of nitrobenzene. - Highlights: • A green synthesis of size controlled Au-NPs from plant extract. • Trace level detection of nitro benzene, a pollutant causing Methemoglobinaemia, at Au-NPs modified electrode. • Achievement of lower LOD and wider linear response. • The proposed sensor exhibits excellent practicality in various water samples. - Abstract: The present study involves a green synthesis of gold nanoparticles (Au-NPs) using Acacia nilotica twig bark extract at room temperature and trace level detection of one of the hazardous materials, viz. nitrobenzene (NB) that causes Methemoglobinaemia. The synthesis protocol demonstrates that the bioreduction of chloroauric acid leads to the formation of Au-NPs within 10 min, suggesting a higher reaction rate than any other chemical methods involved. The obtained Au-NPs have been characterized by UV–vis spectroscopy, X-ray diffraction, transmission electron microscopy, Energy-Dispersive X-ray Spectroscopy and Fourier Transform Infrared Spectroscopy. The electrochemical detection of NB has been investigated at the green synthesized Au-NPs modified glassy carbon electrode by using differential pulse voltammetry (DPV). The Au-NPs modified electrode exhibits excellent reduction ability toward NB compared to unmodified electrode. The developed NB sensor at Au-NPs modified electrode displays a wide linear response from 0.1 to 600 μM with high sensitivity of 1.01 μA μM{sup −1} cm{sup −2} and low limit of detection of 0.016 μM. The modified electrode shows exceptional selectivity in the presence of ions, phenolic and biologically coactive compounds. In addition, the Au-NPs modified electrode exhibits an outstanding recovery results toward NB in various real water samples.

  4. Análisis numérico multivariante en parámetros métricos mandibulares equinos (raza Cavall Pirinenc Català - Multivariant numerical analysis with equine mandibular metric parameters (Cavall Pirinenc Català breed

    Directory of Open Access Journals (Sweden)

    Pere-Miquel Parés i Casanova

    2012-01-01

    Full Text Available ResumenSe analizan 9 variables métricas de 16 mandíbulas procedente de animales adultos de la raza equina Cavall Pirinenc Català.AbstractNine metric parameters were taken on 16 mandibles from adult horses belonging to the Cavall Pirinenc Català breed.

  5. [Removal of trace nitrobenzene in water by VUV/TiO2/O3].

    Science.gov (United States)

    Yin, Jing-jing; Zhang, Peng-yi

    2009-01-01

    The removal of trace nitrobenzene in water by the ozone-enhanced VUV photocatalysis process (VUV/TiO2/O3) was investigated, in which low-pressure mercury lamp emitting 185 nm vacuum ultraviolet and titanium dioxide film coated on the titanium plate were used as light source and photocatalyst respectively. The results show that, VUV/TiO2/O3 is an effective method to remove trace nitrobenzene in water, and the pseudo-first-order rate constant of nitrobenzene in the VUV/TiO2/O3 process is 102.8% and 30.8% higher than that in the UV/TiO2/O3 and VUV/O3 respectively. And 50 microg/L nitrobenzene in deionized water is totally removed within 60 s by the VUV/TiO2/O3 process. Higher ozone dosage is beneficial to accelerate nitrobenzene degradation, and the apparent rate constant at ozone dosage of 1.52 mg/L is 134.4% higher than that without ozone addition. Though the rate constant is slightly decreased with increase of nitrobenzene concentration, 170 microg/L nitrobenzene is removed to below the detection limit within 2 min. Common species such bicarbonate and humic acid in water significantly inhibit the removal of nitrobenzene, and the apparent rate constant is reduced 82.9% and 71.6% respectively when 2 mmol/L bicarbonate and 3.2 mg/L humic acid are added into the water. The inverse of the apparent rate constant is linear with the bicarbonate concentration. Trace nitrobenzene in surface water containing bicarbonate and natural organic matter can be removed fast and effectively by the VUV/TiO2/O3 process, and 96% nitrobenzene with initial concentration of 90 microg/L is removed within 4 min and the UV absorbance at 254 nm is also reduced 80%.

  6. Hydroponic uptake and distribution of nitrobenzene in Phragmites australis: potential for phytoremediation.

    Science.gov (United States)

    Song, Yanyu; Song, Changchun; Ju, Songbai; Chai, Junhai; Guo, Jun; Zhao, Quandong

    2010-03-01

    Phragmites australis was grown hydroponically in nutrient solutions containing nitrobenzene to examine the potential for treatment of contaminated waters through phytoremediation. The hydroponic solutions and plant tissue were sampled each day during the five day growth period and tested for nitrobenzene. Plant tissue analysis included both rhizome and shoot sections of the plant. The average half lives and disappearance rate of nitrobenzene in the nutrient solution was 1.85 days and 88.10%, respectively. The levels of nitrobenzene in rhizomes and shoots of Phragmites australis increased with higher exogenous concentrations. For the highest treatment, nitrobenzene measurements in the rhizome tissue were much higher than the plant shoots until the third day. Shoot sections initially showed elevated concentrations and then decreased. This variation is presumably due to the translocation of the target compound from the rhizomes to shoots. Our findings indicate that Phragmites australis removed nitrobenzene from the hydroponic solutions and accumulated the compound within the plant tissue. This activity makes Phragmites australis a good candidate species for the phytoremediation of nitrobenzene contaminated waters.

  7. Concentration level and geographical distribution of nitrobenzene in Chinese surface waters

    Institute of Scientific and Technical Information of China (English)

    GAO Jijun; LIU Linghua; LIU Xiaoru; ZHOU Huaidong; WANG Zijian; HUANG Shengbiao

    2008-01-01

    Nitrobenzene was reported to occur at relatively high concentrations in some Chinese surface water and to cause an environmental pollution event in 2005. In order to map the distribution of nitrobenzene in the Chinese surface water throughout China, surface water samples were collected from over 600 sites in the 7 major watersheds and three drainage areas. The samples were analyzed for concentration of nitrobenzene. Overall, nitrobenzene was more frequently detected at higher concentrations in the rivers of North China, including Songhuajiang River, Liaohe River, Haihe River, Yellow River, Huaihe River and Northwest drainage area rivers, compared with those in the rivers of South China, including Yangtze river, Pearl river, Southeast drainage area rivers and Southwest drainage rivers. The detection rate of nitrobenzene was the 83.2 % for all the samples, with a mean value of 18.1 ng/L and a range of < 0.3-8,450.0 ng/L. The highest mean concentration of nitrobenzene was observed in the Yellow River, followed by Huaihe River . The results of this investigation indicated that nitrobenzene should be of particular concern in China and its ecological and health risk should be assessed.

  8. Method of reduction of nitroaromatics by enzymatic reaction with redox enzymes

    Science.gov (United States)

    Shah, Manish M.

    2000-01-01

    A method for the controlled reduction of nitroaromatic compounds such as nitrobenzene and 2,4,6-trinitrotoluene by enzymatic reaction with redox enzymes, such as Oxyrase (Trademark of Oxyrase, Inc., Mansfield, Ohio).

  9. Method of controlled reduction of nitroaromatics by enzymatic reaction with oxygen sensitive nitroreductase enzymes

    Science.gov (United States)

    Shah, Manish M.; Campbell, James A.

    1998-01-01

    A method for the controlled reduction of nitroaromatic compounds such as nitrobenzene and 2,4,6-trinitrotoluene by enzymatic reaction with oxygen sensitive nitroreductase enzymes, such as ferredoxin NADP oxidoreductase.

  10. 77 FR 50163 - Importer of Controlled Substances; Notice of Registration; Catalent Pharma Solutions, Inc.

    Science.gov (United States)

    2012-08-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Drug Enforcement Administration Importer of Controlled Substances; Notice of Registration; Catalent Pharma Solutions, Inc. Correction In notice document 2012-19202 appearing on page 47114 in the issue of...

  11. Quantum chemistry based QSAR prediction and priority setting for toxicity of nitrobenzenes on EINECS list

    NARCIS (Netherlands)

    Zvinavashe, E.; Murk, A.J.; Vervoort, J.J.M.; Soffers, A.E.M.F.; Freidig, A.; Rietjens, I.M.C.M.

    2006-01-01

    Fifteen experimental literature data sets on the acute toxicity of substituted nitrobenzenes to algae (Scenedesmus obliquus, Chlorella pyrenoidosa, C. vulgaris), daphnids (Daphnia magna, D. carinata), fish (Cyprinus carpio, Poecilia reticulata), protozoa (Tetrahymena pyriformis), bacteria (Phosphoba

  12. Study on nitrobenzene ratio in water-ice system under different conditions

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A series of ice freezing-thawing experiments are performed under different nitro- benzene concentrations of 1.7, 8, 17, 170, and 1700 μg/L. A special flume, made of stainless steel and glass, is built to simulate the flowing water for the experiments. The ice frozen in cold room has similar crystal structure of natural ice, therefore the behaviors of nitrobenzene in the ice frozen in cold room is also believed to be similar to that in natural ice. The results of the experiments reveal that the freezing rate of ice decreases with the increase of nitrobenzene concentration in water, and that the nitrobenzene ratio in water-ice system becomes higher with the increase of freezing rate. In addition, the nitrobenzene in ice does not move and is only re- leased into water after melt.

  13. Removal of nitrobenzene from aqueous solution by a novel lipoid adsorption material (LAM)

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Qinxue [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090 (China); Chen, Zhiqiang, E-mail: czq0521@tom.com [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090 (China); Lian, Jiaxiang; Feng, Yujie; Ren, Nanqi [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090 (China)

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer We synthesized a novel adsorbent-lipoid adsorption material (LAM). Black-Right-Pointing-Pointer We investigate the adsorption behavior isotherms of nitrobenzene on LAM. Black-Right-Pointing-Pointer We investigate the adsorption kinetics of nitrobenzene on LAM. Black-Right-Pointing-Pointer We proved that the reaction is spontaneous and is an exothermic reaction. Black-Right-Pointing-Pointer The removal efficiency of LAM was higher than that of GAC. - Abstract: In this study, a novel adsorbent referred to as a lipoid adsorption material (LAM) was synthesized with a hydrophobic nucleolus (triolein) and hydrophilic membrane structure (polyamide). The LAM was applied to the adsorption and removal of nitrobenzene from aqueous systems. Experiments were carried out to investigate the adsorption behavior of nitrobenzene on LAM, including the development of adsorption isotherms, the determination of adsorption kinetics, and to explore the influence of adsorbent dosage, contact time, temperature and the initial concentration of nitrobenzene on adsorption. The performance of LAM was compared with equal amounts of granular activated carbon (GAC) for adsorption. The adsorption isotherms for LAM were found to be described by the Linear equation, while the adsorption isotherms for granular activated carbon (GAC) were described by the Freundlich equation. Results indicated that the adsorption of nitrobenzene by LAM occurred mainly due to the partition function caused by the triolein nucleolus. Two kinetics models, pseudo-first-order and pseudo-second-order models were used to fit the experimental data for LAM adsorption. By comparing the correlation coefficients, it was found that the pseudo-first-order model was most suitable to describe the adsorption of nitrobenzene on LAM. The results also indicated that the factors that affect the adsorption rate would be either the nitrobenzene concentration or the character of the adsorbent

  14. Surface properties of SAC and its adsorption mechanisms for phenol and nitrobenzene.

    Science.gov (United States)

    Li, Daojing; Wu, Yunsong; Feng, Li; Zhang, Liqiu

    2012-06-01

    The physicochemical properties of an activated carbon produced from sewage sludge (SAC) were determined and compared with those of a market activated carbon (MAC). Phenol and nitrobenzene were selected as the target compounds and their adsorption behaviors in water and cyclohexane were studied and compared. The experimental results showed that the surface area of SAC was only 1/4 of that of the MAC. Functional groups on the SAC are all acid groups while basic groups are the dominant on the MAC. Based on the properties of the activated carbons and the adsorption behaviors of the two organic pollutants, it could be inferred preliminarily that phenol adsorption was mainly affected by surface area but nitrobenzene adsorption was affected by both surface area and surface functional groups. In water, when the initial concentration is between 0.1 and 10 mmol/L, the maximum phenol and nitrobenzene adsorption capacity of SAC is 0.48 and 1.26 mmol/g respectively, which is 1/4 and 1/3 of that of MAC. In cyclohexane, SAC's phenol adsorption capacity is higher and nitrobenzene adsorption capacity is lower than that in water; but MAC's phenol adsorption capacity does not change much and nitrobenzene adsorption capacity decreases a lot compared that in water. The results further indicate that the hydrophobicity and the polarity of the organic pollutants can greatly affect their adsorption in water. For SAC, polar interaction and hydrophobic interaction may be the main mechanisms affecting the sorption of nitrobenzene in water. For MAC, hydrophobic interaction and π-π interaction may be the main mechanisms affecting the sorption of nitrobenzene in water. For both phenol and nitrobenzene, the adsorption capacities of MAC are higher than that of SAC. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Efficient removal of nitrobenzene by Fenton-like process with Co-Fe layered double hydroxide

    Science.gov (United States)

    Bai, Jianfei; Liu, Yong; Yin, Xiaohong; Duan, Hongtao; Ma, Junhua

    2017-09-01

    Co-Fe layered double hydroxide (Co-Fe LDH) prepared by the co-precipitation method was proposed as the Fenton-like catalyst for nitrobenzene removal. The properties of prepared catalysts were characterized by BET, SEM and XRD analyses. The initial pH, hydrogen peroxide concentration, catalyst dosage and the nitrobenzene concentration on the removal of nitrobenzene have been studied. The best removal efficiency (100%) was obtained at pH = 2.7, [H2O2]0 = 500 mg/L, catalyst dosage = 1 g/L for the initial concentration of 50 mg/L nitrobenzene. Co-Fe LDH retained the catalytic activity after five cycles. The mechanism of nitrobenzene oxidation was radical mediated process, confirmed by the addition of T-butanol (·OH scavenger). The iron leaching was only 12.47 mg/L even at pH 2.7. Moreover, the intermediates were detected by LC/MS and a possible pathway for nitrobenzene removal in the Co-Fe LDH and H2O2 system was proposed.

  16. A novel integrated active capping technique for the remediation of nitrobenzene-contaminated sediment.

    Science.gov (United States)

    Sun, Hongwen; Xu, Xiaoyang; Gao, Guandao; Zhang, Zizhong; Yin, Peijie

    2010-10-15

    The objective of this study was to develop a novel integrated active capping system and to investigate its efficiency in the remediation of nitrobenzene-contaminated sediment. An integrated Fe(0)-sorbent-microorganism remediation system was proposed as an in situ active capping technique to remediate nitrobenzene-contaminated sediment. In this system, nitrobenzene was reduced to aniline by Fe(0), which has a much better biodegradability. The sorption capacity and structural properties of cinder was measured to examine its applicability as the sorbent and matrix for this integrated capping system. Indigenous microorganisms from Songhuajiang River sediment, which was contaminated by nitrobenzene and aniline in Chinese Petrochemical Explosion in Jilin, were acquired one month after the explosion and used in this active capping system to degrade nitrobenzene and its reduced product, aniline. A bench-scale remediation experiment was conducted on a mimicked nitrobenzene-contaminated sediment to investigate the efficiency of the integrated capping system and the synergistic effects of the combined components in the active capping system. The results show that this integrated active capping system can effectively block the release of target pollutants into the upper-layer water and remove the compounds from the environment.

  17. Green synthesis of gold nanoparticles for trace level detection of a hazardous pollutant (nitrobenzene) causing Methemoglobinaemia.

    Science.gov (United States)

    Emmanuel, R; Karuppiah, Chelladurai; Chen, Shen-Ming; Palanisamy, Selvakumar; Padmavathy, S; Prakash, P

    2014-08-30

    The present study involves a green synthesis of gold nanoparticles (Au-NPs) using Acacia nilotica twig bark extract at room temperature and trace level detection of one of the hazardous materials, viz. nitrobenzene (NB) that causes Methemoglobinaemia. The synthesis protocol demonstrates that the bioreduction of chloroauric acid leads to the formation of Au-NPs within 10min, suggesting a higher reaction rate than any other chemical methods involved. The obtained Au-NPs have been characterized by UV-vis spectroscopy, X-ray diffraction, transmission electron microscopy, Energy-Dispersive X-ray Spectroscopy and Fourier Transform Infrared Spectroscopy. The electrochemical detection of NB has been investigated at the green synthesized Au-NPs modified glassy carbon electrode by using differential pulse voltammetry (DPV). The Au-NPs modified electrode exhibits excellent reduction ability toward NB compared to unmodified electrode. The developed NB sensor at Au-NPs modified electrode displays a wide linear response from 0.1 to 600μM with high sensitivity of 1.01μAμM(-1)cm(-2) and low limit of detection of 0.016μM. The modified electrode shows exceptional selectivity in the presence of ions, phenolic and biologically coactive compounds. In addition, the Au-NPs modified electrode exhibits an outstanding recovery results toward NB in various real water samples.

  18. Selective photoreduction of nitrobenzene to aniline on TiO{sub 2} nanoparticles modified with amino acid

    Energy Technology Data Exchange (ETDEWEB)

    Huang Heyong; Zhou Jiahong [Key Lab of Biofunctional Materials of Jiangsu Province, Analysis and Testing Center, Nanjing Normal University, Nanjing 210097 (China); Department of Chemistry and Environmental Science, Nanjing Normal University, Nanjing 210097 (China); Liu Hailong [Department of Chemistry and Environmental Science, Nanjing Normal University, Nanjing 210097 (China); Zhou Yanhuai, E-mail: zhouyanhuai@njnu.edu.cn [Department of Physical Science and Technology, Nanjing Normal University, Nanjing 210097 (China); Feng Yuying, E-mail: yyfeng3@163.com [Key Lab of Biofunctional Materials of Jiangsu Province, Analysis and Testing Center, Nanjing Normal University, Nanjing 210097 (China) and Department of Chemistry and Environmental Science, Nanjing Normal University, Nanjing 210097 (China)

    2010-06-15

    The photoreduction of nitrobenzene (NB) on TiO{sub 2} nanoparticles modified with asparagine (Asp), serine (Ser), phenylalanine (Phe) and tyrosine (Tyr), which were found to bind to TiO{sub 2} via carboxyl group, have been investigated under high-pressure mercury irradiation. Modification of TiO{sub 2} with Asp, Ser and Phe resulted in enhanced photocatalytic degradation rate of NB and high selective activity to aniline (AN) compared to using bare TiO{sub 2}. Furthermore, NB degradation followed a reductive approach over Asp, Ser, Phe-modified TiO{sub 2} whether in additional of methanol or not. The result indicates that modification of TiO{sub 2} with electron-donating groups is an effective way to enhance photoreduction of nitroaromatic compounds.

  19. El movimiento estudiantil catalán en el nuevo ciclo de luchas

    OpenAIRE

    González García, Robert; Benítez Romero, Isabel

    2014-01-01

    Objetivo: analizar la evolución del movimiento estudiantil catalán en los últimos 20 años (1993-2013) para comprender los contextos de implantación de modelos neoliberales de gestión de la universidad y de ciclos de movilización a los que responden las diversas etapas del movimiento.Metodología: a partir de la hermenéutica de procesos sociales y a través del análisis de documentación emitida por el movimiento estudiantil catalán y de un ejercicio de reflexión conjunta de los autores con base ...

  20. Identificació de les vocals tòniques del català

    Directory of Open Access Journals (Sweden)

    Sílvia Planas Morales

    2013-03-01

    Full Text Available El volumen 5 de la Biblioteca Phonica es la versión completa de la investigación de la profesora Sílvia Planas Identificació de les vocal tòniques del català, cuyo resumen se presenta en la revista Phonica con el formato de artículo. Se trata de la versión completa de la tesis doctoral de la autora, presentada en el 2000.

  1. Estudio de puertas catalíticas en sensores de gas en tecnología de SiC

    Directory of Open Access Journals (Sweden)

    Casals, O.

    2004-04-01

    Full Text Available In this work the chemical and structural characterisation of metallic layers of Pt and TaSix, employed as catalytic gates in high temperature gas sensors based on MOS devices on SiC substrates, is presented. For the study layers of different thickness have been deposited on Si substrates. The results show that the roughness of the layers increases with the reduction of the thickness of Pt and with annealing, which should give rise to an increase in the sensitivity and response speed of the devices. Another consequence of the annealing is the chemical transformation of the gate’s materials that, for thin films of Pt with TaSix, produces the complete transformation of Pt into Pt2Ta, which might affect the catalytic properties of the gate. The first electrical results show that, even with thick and compact Pt layers, the SiC-based MOS tunnel diodes are sensitive to CO and NO2 gases, although the response time is relatively long. its response speed is too slow.

    En este trabajo se presenta un estudio químico y estructural de las capas metálicas de Pt y TaSix utilizadas como puerta catalítica en sensores de gas de alta temperatura basados en dispositivos MOS de SiC. Para ello se han depositado capas de diferentes espesores sobre substratos de Si. Los resultados muestran que con la reducción del espesor de Pt y con un recocido se consigue aumentar la rugosidad de las capas de puerta, lo que debería aumentar la sensibilidad y la velocidad de respuesta de los dispositivos que las incorporasen. Otro efecto del recocido es la transformación química del material de la puerta que, para capas delgadas de Pt con TaSix, produce la transformación total Pt en Pt2Ta, lo que podría afectar a las características catalíticas de la puerta. Los primeros resultados eléctricos indican que, a pesar de que las capas de Pt empleadas son gruesas y compactas, los diodos MOS túnel de SiC son sensibles a los gases CO y NO2, aunque presentan una velocidad

  2. Transient grating study of the intermolecular dynamics of liquid nitrobenzene

    Science.gov (United States)

    Wu, Hong-Lin; Song, Yun-Fei; Yu, Guo-Yang; Yang, Yan-Qiang

    2016-10-01

    Femtosecond time-resolved transient grating (TG) technique is used to study the intermolecular dynamics in liquid phase. Non-resonant excitation of the sample by two crossing laser pulses results in a transient Kerr grating, and the molecular motion of liquid can be detected by monitoring the diffraction of a third time-delayed probe pulse. In liquid nitrobenzene (NB), three intermolecular processes are observed with lifetimes of 37.9±1.4 ps, 3.28±0.11 ps, and 0.44±0.03 ps, respectively. These relaxations are assigned to molecular orientational diffusion, dipole/induced dipole interaction, and libration in liquid cage, respectively. Such a result is slightly different from that obtained from OKE experiment in which the lifetime of the intermediate process is measured to be 1.9 ps. The effects of electric field on matter are different in TG and optical Kerr effect (OKE) experiments, which should be responsible for the difference between the results of these two types of experiments. The present work demonstrates that TG technique is a useful alternative in the study of intermolecular dynamics. Project supported by the National Natural Science Foundation of China (Grant Nos. 11304058 and 11404307) and NSAF (Grant No. U1330106).

  3. AN OXIDANT TO REPLACE NITROBENZENE IN LIGNIN ANALYSIS

    Directory of Open Access Journals (Sweden)

    Michael P. Masingale

    2009-08-01

    Full Text Available Four metal organic frameworks (MOFs are being evaluated as possible catalysts for alkaline lignin oxidation. One aspect of the screening process is the oxidation of in-situ hardwood lignin by a high mole ratio of Cu, Fe, or Cu + Fe contained in the MOFs. The MOF’s were prepared in a microwave-assisted synthesis. One of the MOFs, a benzenetricar-boxylic acid complex of Cu (II and Fe (III, converted the phenylpropane (C9 units in in-situ poplar lignin to approximately 50% monomers. The ratio of syringyl (S to guiacyl (G monomers was similar to the S:G ratio obtained from nitrobenzene oxidation (NBO. The S:G ratio from NBO was then compared to that from MOF oxidation (MOFO for two other poplars. The S:G ratios for the three poplars by MOFO were 1.20, 1.51 and 1.67, respectively while the corresponding NBO values were 1.25, 1.45 and 1.68. These initial results indicate that MOFO could be developed into a credible replacement for NBO, because it affords a higher yield of monomers when a large MOF dose is used. Some preliminary results are also presented for MOF acting as a catalyst (100 ppm Cu (II plus 81 ppm Fe (III in NaOH for oxygenation of the hardwoods. The products from O2 + MOF are identical to MOF only, but the ratios amongst them are different.

  4. [Degradation of nitrobenzene in aqueous solution by modified ceramic honeycomb-catalyzed ozonation].

    Science.gov (United States)

    Sun, Zhi-Zhong; Zhao, Lei; Ma, Jun

    2005-11-01

    Comparative experiments of modified ceramic honeycomb, ceramic honeycomb-catalyzed ozonation and ozonation alone were conducted with nitrobenzene as the model organic pollutant. It was found that the processes of modified ceramic honeycomb and ceramic honeycomb-catalyzed ozonation could increase the removal efficiency of nitrobenzene by 38.35% and 15.46%, respectively, compared with that achieved by ozonation alone. Under the conditions of this experiment, the degradation rate of modified ceramic honeycomb-catalyzed ozonation increased by 30.55% with the increase of amount of catalyst to 5 blocks. The degradation rate of three process all increased greatly with the increase of temperature and value of pH in the solution. But when raising the pH value of the solution to 10.00, the advantage of modified ceramic honeycomb-catalyzed ozonation processes lost. The experimental results indicate that in modified ceramic honeycomb-catalyzed ozonation, nitrobenzene is primarily oxidized by *OH free radical in aqueous solution. The adsorption of nitrobenzene is too limited to have any influence on the degradation efficiency of nitrobenzene. With the same total dosage of applied ozone, the multiple steps addition of ozone showed a much higher removal efficiency than that obtained by one step in three processes. Modified ceramic honeycomb had a relative longer lifetime.

  5. [Characteristics of nitrobenzene containing wastewater catalytic oxidation degradation by Fenton reagent].

    Science.gov (United States)

    Wei, C; Chen, C; Wang, G; Ren, Y; Wu, C; Wu, H

    2001-09-01

    Through the alteration of the concentration of catalyst and oxidant, the rulers and dynamics of nitrobenzene oxidized by Fenton reagent in different concentrations were studied. The correlativity of the reaction time and relatively remain nitrobenzene was analyzed by the unitary linear regress equation. The result of the analysis proves that the coefficient was over the critical constant. The oxidation of nitrobenzene by Fenton reagent was in conformity with first-order dynamics model and the reaction rate constant was got at the same time. The idea, using the complex of Fe as the catalyst replacing Fe2+ in the Fenton Reaction, not only got a higher reaction velocity and efficiency, but also had a distinct exclusive to the degradation of nitrobenzene. The remove velocity of nitrobenzene was improved from 17.48 mg/(L.min) to 71.22 mg/(L.min), the remove rate in 5 minutes was from 9.74% to 91.79%. The nonhomogeneous catalyst made by the artificial zeolite with Fe-complex adsorbed had the same catalyzing behavior. In addition, ultraviolet radiation can also improves the Fenton reaction to some degree. These research works could demonstrate the good application potentiality of Fenton reagent in treating wastewater.

  6. [Solubilization of nitrobenzene in micellar solutions of Tween 80 and inorganic salts].

    Science.gov (United States)

    Li, Sui; Zhao, Yong-sheng; Xu, Wei; Dai, Ning

    2008-04-01

    The solubilization of nitrobenzene by a nonionic surfactant Tween 80 was investigated at 10 degrees C. Experimental results indicated that the solubility of nitrobenzene in water was greatly enhanced by Tween 80 at surfactant concentration above CMC(critical micelle concentration) and a linear relationship was obtained between surfactant concentration and nitrobenzene concentration from the solubility curve. The molar solubilization ratio (MSR) value was 5.093 and IgKm was 3.499. The solubilization was attributed to the ethoxylation group in Tween 80 micellar. Effect of four inorganic salts such as NaCl, KCl, CaCl2 , MgCl2 on water solubilities of nitrobenzene in Tween 80 micellar solutions was also investigated by a matrix of batch experiments. Mix the Tween 80-inorganic salts at the total mass ratios of 2:1, 5:1 and 10:1. The results show that the inorganic salts at a high concentration( > or = 500 mg x L(-1)) can enhance the solubilization capacities of Tween 80 micellar solution and increase the value of MSR and IgKm . Because of the salting-out effect between the micellar of Tween 80 and inorganic salts, the volume of micelle turns bigger, which may provide larger solubility volume for nitrobenzene. The mixture of nonionic surfactant and inorganic salts can be used in subsurface remediation as a flushing solution.

  7. Experimental study on oxidative decomposition of nitrobenzene in aqueous solution by honeycomb ceramic-catalyzed ozonation

    Institute of Scientific and Technical Information of China (English)

    Lei ZHAO; Jun MA; Zhizhong SUN; Zhengqian LIU; Yixin YANG

    2008-01-01

    The ozonation of nitrobenzene in aqueous solu-tion was carried out in a semi-batch reactor to investigate the degradation efficiency, the effect factors, and the reaction mechanism, where honeycomb ceramic was used as a cata-lyst. The presence of honeycomb ceramic could improve the degradation rate of nitrobenzene by 15.46% compared to the results ofozonation alone. Under the conditions of this exper-iment, the degradation rate of honeycomb ceramic-catalyzed ozonation increased by 12.94% with the increase of the amount of catalyst from 1 to 5 blocks. The degradation rates all increased greatly with the increase of temperature and pH of the solution in the processes of honeycomb ceramic-catalyzed ozonation and ozonation alone. But, when the pH of the solution increased to 9.50, the advantage of the honey-comb ceramic-catalyzed ozonation process would be lost. The experimental findings indicated that in the processes of ozonation alone and honeycomb ceramic-catalyzed ozona-tion, nitrobenzene was primarily oxidized by·OH free radical in aqueous solution. The adsorption of nitrobenzene was too limited to have an important influence on the degradation rate of nitrobenzene. With the same total dosage of applied ozone, the multiple step addition of ozone showed much higher removal efficiency than that obtained by one step in the two processes.

  8. The fate of a nitrobenzene-degrading bacterium in pharmaceutical wastewater treatment sludge.

    Science.gov (United States)

    Ren, Yuan; Yang, Juan; Chen, Shaoyi

    2015-12-01

    This paper describes the fate of a nitrobenzene-degrading bacterium, Klebsiella oxytoca NBA-1, which was isolated from a pharmaceutical wastewater treatment facility. The 90-day survivability of strain NBA-1 after exposure to sludge under anaerobic and aerobic conditions was investigated. The bacterium was inoculated into sludge amended with glucose and p-chloronitrobenzene (p-CNB) to compare the bacterial community variations between the modified sludge and nitrobenzene amendment. The results showed that glucose had no obvious effect on nitrobenzene biodegradation in the co-metabolism process, regardless of the presence/absence of oxygen. When p-CNB was added under anaerobic conditions, the biodegradation rate of nitrobenzene remained unchanged although p-CNB inhibited the production of aniline. The diversity of the microbial community increased and NBA-1 continued to be one of the dominant strains. Under aerobic conditions, the degradation rate of both nitrobenzene and p-CNB was only 20% of that under anaerobic conditions. p-CNB had a toxic effect on the microorganisms in the sludge so that most of the DGGE (denaturing gradient gel electrophoresis) bands, including that of NBA-1, began to disappear under aerobic conditions after 90days of exposure. These data show that the bacterial community was stable under anaerobic conditions and the microorganisms, including NBA-1, were more resistant to the adverse environment.

  9. Morfología cefálica en el Cavall pirinenc català (Cephalic morphology in the Cavall pirinenc català breed

    Directory of Open Access Journals (Sweden)

    Pere-Miquel Parés i Casanova

    2009-09-01

    Full Text Available ResumenSe han analizado 35 variables métricas de 19 cráneos procedentes deanimales adultos de la raza equina Cavall Pirinenc Català,procediendo a su estudio por Análisis de Componentes Principales.Las variables relacionadas con la anchura del neurocráneo, laslongitudes ventrales y las variables relacionadas con la órbita ocularson muy poco discriminantes. En cambio, las variables relacionadascon el viscerocráneo aparecen como especialmente discriminantes.Proponemos dar un especial énfasis, en estudios raciales equinossobre material óseo, al trabajo con las medidas que corresponden aesta zona (longitud del diastema, anchura mínima del espaciointeralveolar, longitud de la línea ocular anterior, altura facialcranealmente a P2, altura facial entre P4 y M1, asi como la LongitudFrontal.SummaryThirty-five metric parameters were taken on 19 skulls belonging toadult Cavall Pirinenc Català horse breed and were subjected to aPrincipal Component Analysis. Parameters related with neurocraniumwidth, ventral lengths and those related with ocular orbit are poorlydiscriminants. On the other hand, parameters related withviscerocranium are strongly discriminant. Our study strengths theimportance in using parameters linked to viscerocranium, and frontallength, in equine racial studies on bone.

  10. Internal rotation potential and structure of six fluorine substituted nitrobenzenes studied by microwave spectroscopy supported by quantum chemical calculations

    DEFF Research Database (Denmark)

    Larsen, Niels Wessel; Nielsen, Ole Vesterlund

    2014-01-01

    Microwave spectra of the vibrational ground state and several torsionally excited states were used to investigate the internal rotation potential and the structure of six fluorine substituted nitrobenzenes: 3-fluoro- and 4-fluoronitrobenzene were planar molecules just as nitrobenzene whereas 2...

  11. Prediction of the environmental fate and aquatic ecological impact of nitrobenzene in the Songhua River using the modified AQUATOX model

    Institute of Scientific and Technical Information of China (English)

    LEI Bingli; HUANG Shengbiao; QIAO Min; LI Tianyun; WANG Zijian

    2008-01-01

    An accidental discharge of nitrobenzene happened in November 2005 in the Songhuajiang River, China. The AQUATOX model was modified and adapted to simulate the time-dependent nitrobenzene distribution in this multimedia aquatic system and its potential ecological impacts. Nitrobenzene concentrations in flowing water, sediment, and biota were predicted. Based on the initial concentrations of nitrobenzene observed on the field during the accidental discharge, that is, 0.167-1.47 mg/L at different river segments, the predicted water concentrations of nitrobenzene would decrease to 0.02 and 0.002 mg/L after twenty days and one month, respectively. Both model prediction and field observation were in good agreement. The predicted nitrobenzene concentrations in sediments and aquatic organisms would be lower than 0.025 and 0.002 mg/kg, respectively, after two months. Among environmental factors affecting nitrobenzene concentrations in water, inflow water dilution, water temperature, and initial concentration were the most important, by sensitivity analysis. Comparing the perturbed simulation and control simulation, the biomass changes for diatoms and mussel were significantly affected, whereas, no influence on other organisms could be predicted. Therefore the results indicated that nitrobenzene pollution in the Songhuajiang River should have a limited impact on the benthos community.

  12. Adsorption, desorption and condensation of nitrobenzene solution from active carbon: a comparison of two cyclodextrins and two surfactants.

    Science.gov (United States)

    Chen, Ming; Cui, Lei; Li, Chunhui; Diao, Guowang

    2009-02-15

    The adsorption of nitrobenzene on active carbon was researched. The experimental results shown the adsorption of nitrobenzene on active carbon can be described by Freundlich's adsorption model. On the other hand, beta-cyclodextrin (beta-CD) and hydroxypropyl-beta-cyclodextrin (HP-beta-CD) can react with nitrobenzene to form inclusion complex, which will enhance the aqueous solubility of nitrobenzene. By using different concentrations of beta-CD and HP-beta-CD as extractants, nitrobenzene on active carbon has been desorbed statically. As a comparison, surfactant CTAB and SDS were also selected as extractants. The desorbing of mechanism has been discussed. The low concentration of NB was effectively condensed by enrichment of active carbon and desorption of HP-beta-CD. HP-beta-CD is regarded as a potential extractant to deal with soil, sediment or active carbon.

  13. QSAR studies for the acute toxicity of nitrobenzenes to the Tetrahymena pyriformis

    Directory of Open Access Journals (Sweden)

    Wang Dan-Dan

    2014-01-01

    Full Text Available Quantitative structure-activity relationship (QSAR models play a key role in finding the relationship between molecular structures and the toxicity of nitrobenzenes to Tetrahymena pyriformis. In this work, genetic algorithm, along with partial least square (GA-PLS was employed to select optimal subset of descriptors that have significant contribution to the toxicity of nitrobenzenes to Tetrahymena pyriformis. A set of five descriptors, namely G2, HOMT, G(Cl…Cl, Mor03v and MAXDP, was used for the prediction of the toxicity of 45 nitrobenzene derivatives and then were used to build the model by multiple linear regression (MLR method. It turned out that the built model, whose stability was confirmed using the leave-one-out validation and external validation test, showed high statistical significance (R2=0.963, Q2LOO=0.944. Moreover, Y-scrambling test indicated there was no chance correlation in this model.

  14. [Pathway of aqueous ferric hydroxide catalyzed ozone decomposition and ozonation of trace nitrobenzene].

    Science.gov (United States)

    Ma, Jun; Zhang, Tao; Chen, Zhong-lin; Sui, Ming-hao; Li, Xue-yan

    2005-03-01

    In this paper, the decomposition rate of ozone in water was measured over GAC and ferric hydroxide/GAC (FeOOH/GAC) catalyst and the mechanism of ozone catalytic decomposition was discussed. The catalytic ozonation activity of trace nitrobenzene in water was determined on several metal oxides and correlated with their surface density of hydroxyl groups and pHzpc,(pH of zero point of charge). The results show that: 1) The pseudo-first order rate of ozone decomposition increased by 68 and 108 percent for GAC and FeOOH/GAC catalysts respectively; 2) When t-butanol was added, the rate constant decreased by 9 % for GAC and 20% for FeOOH/GAC; 3) There was no direct correlation between surface density of hydroxyl groups and the activity of catalytic ozonation of nitrobenzene; 4) The oxide surface at nearly zero charged point was favorable for the catalytic ozonation of nitrobenzene.

  15. Stability of the barium–benzo-15-crown-5 complex in nitrobenzene saturated with water

    Directory of Open Access Journals (Sweden)

    E. MAKRLÍK

    2006-11-01

    Full Text Available From extraction experiments and g-activity measurements, the exchange extraction constant corresponding to the equilibrium Ba2+(aq + SrL22+(nb D BaL22+(nb + Sr2+(aq occurring in the two-phase water–nitrobenzene system (L =benzo-15-crown-5; aq = aqueous phase, nb = nitrobenzene phase was evaluated as log Kex (Ba2+, SrL22+ = 0.3 ± 0.1. Furthermore, the stability constant of the benzo-15-crown-5–barium complex in nitrobenzene saturated with water was calculated for the temperature of 25 °C: log bnb (BaL22+=13.3±0.1.

  16. UV-Irradiated Photocatalytic Degradation of Nitrobenzene by Titania Binding on Quartz Tube

    Directory of Open Access Journals (Sweden)

    Thou-Jen Whang

    2012-01-01

    Full Text Available A new method for UV-irradiated degradation of nitrobenzene by titania photocatalysts was proposed, titania nanoparticles were coated on a quartz tube through the introduction of tetraethyl orthosilicate into the matrix. The dependence of nitrobenzene photodegradation on pH, temperature, concentration, and air feeding was discussed, and the physical properties such as the activation energy, entropy, enthalpy, adsorption constant, and rate constant were acquired by conducting the reactions in a variety of experimental conditions. The optimum efficiency of the photodegradation with the nitrobenzene residue as low as 8.8% was achieved according to the experimental conditions indicated. The photodegradation pathways were also investigated through HPLC, GC/MS, ion chromatography (IC, and chemical oxygen demand (COD analyses.

  17. Prediction of toxicity of nitrobenzenes using ab initio and least squares support vector machines

    Energy Technology Data Exchange (ETDEWEB)

    Niazi, Ali [Department of Chemistry, Faculty of Sciences, Azad University of Arak, Arak (Iran, Islamic Republic of)], E-mail: ali.niazi@gmail.com; Jameh-Bozorghi, Saeed; Nori-Shargh, Davood [Department of Chemistry, Faculty of Sciences, Azad University of Arak, Arak (Iran, Islamic Republic of)

    2008-03-01

    A quantitative structure-property relationship (QSPR) study is suggested for the prediction of toxicity (IGC{sub 50}) of nitrobenzenes. Ab initio theory was used to calculate some quantum chemical descriptors including electrostatic potentials and local charges at each atom, HOMO and LUMO energies, etc. Modeling of the IGC{sub 50} of nitrobenzenes as a function of molecular structures was established by means of the least squares support vector machines (LS-SVM). This model was applied for the prediction of the toxicity (IGC{sub 50}) of nitrobenzenes, which were not in the modeling procedure. The resulted model showed high prediction ability with root mean square error of prediction of 0.0049 for LS-SVM. Results have shown that the introduction of LS-SVM for quantum chemical descriptors drastically enhances the ability of prediction in QSAR studies superior to multiple linear regression and partial least squares.

  18. Intensified photocatalytic degradation of nitrobenzene by Pickering emulsion of ZnO nanoparticles

    Institute of Scientific and Technical Information of China (English)

    Wei Wu; Shuang Gao; Weixia Tu; Jianfeng Chen; Pengyuan Zhang

    2010-01-01

    In this paper,zinc oxide nanoparticles were first prepared and surface-modified.A Picketing emulsion was then prepared,consisting of nitrobenzene(oil phase),water(water phase)and the modified zinc oxide nanoparticles located on the water-oil interface.The effects of different emulsions on the removal rate of nitrobenzene by photocatalytic degradation were studied.The results proved that use of a Pick-eting emulsion stabilized by surface-modified ZnO nanoparticles provides an effective and novel way to intensify the photocatalytic degradation of the organic contaminant.

  19. HYDROGENATION OF NITROBENZENE TO FORM ANILINE IN LIQUID PHASE AT ATMOSPHERIC PRESSURE

    Institute of Scientific and Technical Information of China (English)

    YINJingbo; ZhubanovK.A; 等

    2001-01-01

    Aromatic amine compounds and their derivatives are important intermediates of fine chemicals like dye and medicine.The former hydrogenation catalyst has many problems,such as environment pollution caused by old technology,strict reaction condtion,complicated equipment,bad property of catalyst and so on.Holy [1] firstly reported the hydrogenation of nitrobenzene on modified polystyrene Pd catalyst.But how to improve the activity,selectivity and stability of the polymer suppoorter catalyst needs to studyfurther.We prepared a series of polymer supported catalysts by the methods of adsorption and mechanical mixting ,selected a high active catalyst Pd-Ah-1 by observing the hydrogenation of nitrobenzene.

  20. HYDROGENATION OF NITROBENZENE TO FORM ANILINE IN LIQUID PHASE AT ATMOSPHERIC PRESSURE

    Institute of Scientific and Technical Information of China (English)

    YIN Jingbo; YANG Yana; Zhubanov K.A; Bizhanowa N.B

    2001-01-01

    Aromatic amine compounds and their derivatives are important intermediates of fine chemicals like dye and medicine. The former hydrogenation catalyst has many problems, such as environment pollution caused by old technology, strict reaction condition, complicated equipment,bad property of catalyst and so on. Holy [1] firstly reported the hydrogenation of nitrobenzene on modified polystyrene Pd catalyst. But how to improve the activity, selectivity and stability of the polymer supporter catalyst needs to studyfurther. We prepared a seriesof polymer supported catalysts by the methods of adsorption and mechanical mixting, selected a high active catalyst Pd-AH-1 by observing the hydrogenation of nitrobenzene.

  1. Degradation of nitrobenzene-containing wastewater by carbon nanotubes immobilized nanoscale zerovalent iron

    Science.gov (United States)

    Jiao, Weizhou; Feng, Zhirong; Liu, Youzhi; Jiang, Huihui

    2016-07-01

    Nanoscaled zerovalent iron (NZVI)-multiwalled carbon nanotubes (CNTs) composite materials were prepared by in situ reduction of Fe2+ onto CNTs for nitrobenzene (NB) degradation. The morphologies and the composites of the prepared materials were characterized by SEM, TEM, and XRD. The results showed that the agglomeration of NZVI decreased with NZVI dispersed well onto the surfaces of CNTs, the particle size of NZVI on CNTs was about 20-50 nm. The BET surface areas of NZVI-CNTs was about 95.8 m2/g, which was 39 % higher than that of bare NZVI. For storage, the prepared NZVI-CNTs were concentrated into slurry and stored in situ as fresh slurry without drying. Contrast experiment results showed that the removal efficiency of NB by NZVI-CNTs fresh slurry was 30 % higher than that of vacuum-dried NZVI-CNTs, which indicates that storing in situ as fresh slurry can be an alternative strategy for nanoparticle storage. Batch experiment results showed that NB could be degraded to aniline by NZVI-CNTs rapidly, and the appropriate pH can be conducted at a relatively wide range from 2.0 to 9.0. The optimum mass ratio of iron-carbon was 1:1, and removal efficiency of NB by NZVI-CNTs with this mass ratio can achieve 100 % within 1 min. The degradation process of NB to intermediates was accelerated significantly by NZVI-CNTs, however, there was still a long term for the intermediates to transfer completely into the final product of aniline. The existence of CNTs can improve the formation of aniline through accelerating the electron transfer by forming microscopic galvanic cells with NZVI.

  2. Nitrobenzene biodegradation ability of microbial communities in water and sediments along Songhua River after a nitrobenzene pollution event

    Institute of Scientific and Technical Information of China (English)

    LI Zonglai; YANG Min; LI Dong; QI Rong; LIU Huijuan; SUN Jingfang; QU Jiuhui

    2008-01-01

    More than 100 t of nitrobenzene (NB) and related compounds were discharged into the Songhua River, the fourth longest river in China, because of the world-shaking explosion of an aniline production factory located in Jilin City on November 13, 2005. As one of the efforts to predict the fate of residual NB in the river, NB biodegradation abilities of the microbes in the water and sediments from different river sections were evaluated systematically. The results indicated that microbial communities from any section of the river, including one section at the upper stream of the NB discharging point, had the ability to biodegrade NB under aerobic (for river water samples) conditions at 22±1℃ or anaerobic (for sediment samples) conditions at 10±1℃. NB degradation rates of microbial communities in the downstream sites were markedly higher than those in the upstream site, indicating that the NB degradation abilities were enhanced because of the pollution of NB. Aerobic degradation got neglected at a temperature of 10℃ or lower. The production of nitrosobenzene and aniline during the aerobic biodegradation suggested the existence of at least two different NB degradation pathways, and the occurrence of the catechol-2,3-dioxygenase (C23O) gene and the significant decrease of dissolved organic carbon (DOC) indicated that NB could be mineralized under aerobic conditions. Although it was a fact that the river have frozen-up during the NB accident, it was speculated that biodegradation was not the major process responsible for the decrease of NB flux in the river.

  3. L'"Atles interactiu de l'entonació del català" i el traçat de les isoglosses entonatives del català

    Directory of Open Access Journals (Sweden)

    Pilar Prieto

    2014-02-01

    les isoglosses prosòdiques en el domini lingüístic català. Per una banda, veurem que hi ha contorns entonatius que són molt generals a tot el domini, com ara els contorns de les frases declaratives neutres i els de les declaratives que expressen un sentit d’obvietat; per altra banda, hi ha uns altres contorns, com els de les preguntes informatives i els de les preguntes confirmatòries, que presenten força diversitat dialectal. En la part final de l’article analitzem aquesta variació geoprosòdica i presentem una hipòtesi diacrònica de l’evolució d’aquests contorns.

  4. L'expressió de la incredulitat en català: un estudi prosòdic

    Directory of Open Access Journals (Sweden)

    Verònica Crespo-Sendra

    2014-02-01

    l’anàlisi de les oracions interrogatives absolutes neutres i les interrogatives absolutes que denoten incredulitat de l’"Atles interactiu de l’entonació del català", tot iniciant el traçat de les isoglosses prosòdiques en el domini lingüístic català. En la segona part de l’article presentem els resultats d’un experiment de percepció en català central que pretén investigar quins trets prosòdics són els que calen als parlants per a distingir els dos tipus d’oracions interrogatives que analitzem.

  5. Amelioration of nitrobenzene-induced nephrotoxicity by the ethanol extract of the herb Euphorbia hirta

    Directory of Open Access Journals (Sweden)

    Subramanian Suganya

    2011-01-01

    Full Text Available Background: Euphorbia hirta (L. (Euphorbiaceae is a very popular herb amongst practitioners of traditional medicine and used in the treatment of female disorders, respiratory ailments, tumors, jaundice, digestive problems, wounds, etc. We aimed to evaluate the protective effect of E. hirta against nitrobenzene-induced nephrotoxicity in albino rats. Materials and Methods: The nephroprotective activity of the ethanol extract of E. hirta (400 mg/kg body weight was studied in nitrobenzene-induced albino rats (1000 mg/kg body weight. The activities of antioxidant enzymes superoxide dismutase (SOD, catalase (CAT, glutathione peroxidase (GPx, glutathione-S-transferase (GST, and the levels of reduced glutathione (GSH, total thiols and vitamin C in the kidney tissues were determined. Histopathologic investigation was performed in the kidney tissue samples. Results: Nitrobenzene administration significantly (P < 0.01 enhanced the lipid peroxidation and significantly (P < 0.05 depleted the levels of SOD, CAT, GPx, GST, GSH, total thiols and vitamin C. Treatment with the ethanol extract of E. hirta significantly normalized the antioxidant levels. The nephroprotective activity was also supported by histopathologic studies of kidney tissue. Conclusion: The results indicate that the ethanol extract of E. hirta ameliorates renal dysfunction and could be used as an effective protector against nitrobenzene-induced nephrotoxicity, primarily through its antioxidant capacity.

  6. Spectroscopically resolved competition between dissociation and detachment from nitrobenzene radical anion

    NARCIS (Netherlands)

    Steill, J. D.; Oomens, J.

    2011-01-01

    We report the vibrational spectrum of the gas-phase isolated nitrobenzene radical anion. The spectrum has been acquired by infrared multiple-photon absorption induced dissociation and electron detachment using the FT mass spectrometer coupled to the infrared free-electron laser FELIX. Upon wavelengt

  7. One pot synthesis of cyclohexanone oxime from nitrobenzene using a bifunctional catalyst.

    Science.gov (United States)

    Rubio-Marqués, Paula; Hernández-Garrido, Juan Carlos; Leyva-Pérez, Antonio; Corma, Avelino

    2014-02-18

    Cyclohexanone oxime is formed from nitrobenzene with 97% yield in a one-pot reaction catalysed by palladium and gold nanoparticles on carbon. The reaction is carried out under hydrogen at 60 °C and the overall transformation involves a multi-step catalysed mechanism from which intermediates and catalytically active species have been identified.

  8. FATAL AND RECURRENT METHEMOGLOBINEMIA AFTER INGESTI ON OF PRINTING REDUCER DYE (NITROBENZENE

    Directory of Open Access Journals (Sweden)

    Shahid

    2013-03-01

    Full Text Available Nitrobenzene, a pale yellow oily liquid with an odou r of bitter almonds is used as intermediate in the synthesis of aniline dyes, and as a solvent for the manufacture of cellulose ethers and acetate, as a flavouring agent and in ru bber industry. Nitrobenzene induces methemoglobinemia and this is responsible for the ma nifestations. It is important to take care of the secondary cycling of nitrobenzene from body stores in patients presenting late, after heavy exposure. Clues for diagnosis are a history of chemical ingestion. The characteristic smell of almonds, central cyanosis with no apparent respirat ory distress, low pulse oximeter (observed oxygen saturation with normal ABG (calcu lated oxygen saturation and persisting cyanosis on oxygen therapy, without severe cardiopulm onary disease. Dark brown blood that fails to turn bright red on shaking suggests methem oglobinemia and this is supported by chocolate red colour of dried blood. To manage chem ically induced methemoglobinemia properly, a clinician must be aware of its pathophysiol ogy, be skilled with the use of reducing agents such as methylene blue, and understand specif ic physiochemical properties of the toxin. Acute poisoning with nitrobenzene is presented where clinical evaluation and timely management, with repeated intravenous methylene blu e helped to save a life.

  9. Correlats acústics de l'accent secundari en català

    OpenAIRE

    Prieto Vives, Pilar,

    2003-01-01

    Aquest estudi analitza els correlats acústics de l’accent secundari en català. En primer lloc, s’ha dut a terme un experiment de producció l’objectiu del qual és comparar els paràmetres de duració, F0 i intensitat de síl·labes amb els següents suposats nivells accentuals: (1) sense accent (picà); (2) amb accent primari (pica);(3) amb accent rítmic (picaresca); (4) amb accent secundari en mots compostos (picaferro). Els resultats mostren que els accents secundaris dels tipus examinats en aques...

  10. Tratamiento catalítico de las emisiones de NOx en motores diesel

    OpenAIRE

    Córdoba, Luis Fernando; Montes de Correa, Consuelo

    2002-01-01

    Se presenta una revisión sobre algunos aspectos del funcionamiento de los motores diesel, las emisiones contaminantes producidas, así como las tecnologías catalíticas disponibles para el tratamiento de dichas emisiones. Se introduce además, el desempeño de un catalizador desarrollado en el grupo Catálisis Ambiental para la reducción de NOx en mezclas sintéticas que simulan las emisiones de motores diesel. Palabras clave: motor diesel, emisiones, tratamiento, catalizadores.

  11. Synergistic Extraction of Some Univalent Cations into Nitrobenzene by Using Sodium Dicarbollylcobaltate and Dibenzo-21-crown-7.

    Science.gov (United States)

    Makrlík, Emanuel; Vaňura, Petr

    2012-06-01

    From extraction experiments and γ-activity measurements, the exchange extraction constants corresponding to the general equilibrium M+ (aq) + 1•Na+ (nb) 1•M+ (nb) + Na+ (aq) taking place in the two-phase water-nitrobenzene system (M+ = Li+, H+, NH+4, Ag+, K+, Rb+, Tl+, Cs+; 1 = dibenzo-21-crown-7; aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Furthermore, the stability constants of the 1•M+ complexes in water - saturated nitrobenzene were calculated; they were found to increase in the series of H+ < Ag+ < Li+ < Cs+ < K+, Rb+ < NH+4 < Tl+.

  12. Estudio del empleo de un convertidor catalítico para las emisiones gaseosas en un motor de ignición por chispa usando etanol como combustible. // Study of the employment of a catalytic convertor for the gassy emissions in an spark ignition engine using et

    Directory of Open Access Journals (Sweden)

    K. C. R. Martins

    2005-01-01

    Full Text Available Con este trabajo de investigación se estudia el índice de emisiones gaseosas en un motor de ignición por chispa movido conetanol y se analiza el control de estas emisiones con aplicación de un convertidor catalítico platino/paladio (Pt/Pd en elsistema de descarga del motor. Fueron realizados ensayos dinamométricos de un motor de combustión interna MCI paraanalizar las emisiones y el control de estas, en condiciones operacionales, en función de la rotación y ángulo de avance deignición. El convertidor catalítico alcanzó un 75% de eficiencia cuando el ángulo de avance de ignición del motor aumentópara 16o. Se observó que en rotaciones de 2000 r.p.m el convertidor catalítico presentó mayor reducción de las emisionesde hidrocarburos no quemados HC, monóxido de carbono CO y óxidos de nitrógeno NOx. Con la aplicación de unconvertidor catalítico en un vehículo se debe estandarizar nuevas regulaciones en cuanto al ángulo de avance de igniciónpara optimizar el funcionamiento del motor.Palabras claves: Convertidor catalítico; emisiones de escape; eficiencia catalítica; etanol.____________________________________________________________________________Summary.With this investigation work the index of gassy emissions is studied in an spark ignition engine using ethanol, the control ofthese emissions is analyzed with application of a platinum/palladium (Pt/Pd catalytic convector in the engine dischargesystem. Rehearsals carried out in engines in order to analyze the emissions and the control of these, under operationalconditions, in function of the rotation and angle of ignition advance were carried out. The catalytic convector reaches 75%of efficiency when the ignition advance angle of the engine increased to 16o. It was observed that in rotations of 2000r.p.m the catalytic convector presented bigger reduction of the emissions of non-burnt hydrocarbons HC, monoxide ofcarbon CO and nitrogen oxides NOx. With the application of a

  13. Trets acústics de les vocals del català central

    Directory of Open Access Journals (Sweden)

    Agnès Rius-Escudé

    2014-11-01

    Full Text Available Presentem una proposta d’investigació basada en l’anàlisi acústica de les vocals i de la seva combinació en català central en parla espontània. Per portar-la a terme, hem utilitzat el Corpus oral de parla espontània (Font-Rotchés, 2006 i Rius-Escudé, en premsa. Els informants són d’ambdós sexes, d’edats compreses entre 18 i 80 anys, de professions diverses i procedents de diferents contrades de la varietat dialectal central, en un context de parla espontània real i genuïna. La metodologia serà experimental, empírica i quantitativa. Ens servirem de l’aplicació d’anàlisi i síntesi de veu praat, i del programa SPSS per comprovar la fiabilitat dels resultats. La finalitat d’aquesta investigació és que pugui esdevenir una aportació en el coneixement de la caracterització acústica de les vocals de la llengua catalana en parla espontània i que pugui facilitar-ne el desenvolupament d’aplicacions didàctiques que afavoreixin l’ensenyament-aprenentatge de la pronúncia del català als nous aprenents d’aquesta llengua en els diversos nivells educatius.

  14. [Degradation of trace nitrobenzene in aqueous solution by ozone with catalysis of nanosized TiO2 supported on haydite].

    Science.gov (United States)

    Zhang, Jing; Ma, Jun; Yang, Yi-xin; Wang, Sheng-jun; Qin, Qing-dong

    2007-10-01

    This paper presented the results of catalytic degradation of nitrobenzene by ozone in the presence of nanosized TiO2 supported on haydite, and evaluated influencing factors and the pathway of degradation. Catalysts were prepared by sol-sel method, and sintered in electrical resistance furnace. The optimum sinter temperature was found for preparing the catalyst. The SEM was also used to characterize the catalyst. When the catalyst was sintered at 700 degrees C, it had the best property of catalysis. The catalytic ozonation of nitrobenzene was first order reaction with respect to the concentration of nitrobenzene, and OH* was the dominating species in the oxidation process. As the dose of catalyst increased, the removing rate of nitrobenzene also increased. The highest ozonation rate of this compound, which is 46.5%, was found when pH value was approximately 10. Besides, the catalyst showed good ability after 3 times repeated uses.

  15. Production of 3-nitrocatechol by oxygenase-containing bacteria: optimization of the nitrobenzene biotransformation by Nocardia S3.

    Science.gov (United States)

    Kieboom, J; van den Brink, H; Frankena, J; de Bont, J A

    2001-04-01

    Twenty-one microorganisms were screened for their ability to convert nitroaromatics into 3-nitrocatechol as a result of the action of an oxygenase. Cultures containing toluene dioxygenases and phenol monooxygenases accumulated 3-nitrocatechol during incubation with nitrobenzene and nitrophenol, respectively. Nocardia S3 was selected and studied in more detail. Toluene-pregrown cultures were able to degrade nitrobenzene with a concomitant formation of 3-nitrocatechol. The rates of nitrobenzene utilization decreased throughout the biotransformation period and finally the accumulation ceased. The gradual deterioration of the biotransformation rates was not a consequence of depletion of the NADH pool, but was due to the accumulation of 3-nitrocatechol. The inhibition of nitrobenzene biotransformation by 3-nitrocatechol greatly impacts 3-nitrocatechol production processes.

  16. Effects of hydraulic retention time and nitrobenzene concentration on the performance of sequential upflow anaerobic filter and air lift reactors in treating nitrobenzene-containing wastewater

    DEFF Research Database (Denmark)

    Wu, Jinhua; Chen, Guocai; Gu, Jingjing;

    2014-01-01

    Sequential upflow anaerobic filter (UAF)/air lift (ALR) reactors were employed to investigate the effects of hydraulic retention time (HRT) and nitrobenzene (NB) concentration on treatment of NB-containing wastewater. The results showed that NB was effectively reduced to aniline (AN) with glucose...... and the influent NB concentration increased from 400 to 800 mg l super(-1), respectively. The results showed that sequential UAF/ALR system can be operated at low HRTs and high NB concentrations without significantly affecting the removal efficiency of NB in the reactor system. The UAF/ALR system can provide...... an effective yet low cost method for treatment of NB-containing industrial wastewater....

  17. Microbial Community in a Biofilter for Removal of Low Load Nitrobenzene Waste Gas

    Science.gov (United States)

    Zhai, Jian; Wang, Zhu; Shi, Peng; Long, Chao

    2017-01-01

    To improve biofilter performance, the microbial community of a biofilter must be clearly defined. In this study, the performance of a lab-scale polyurethane biofilter for treating waste gas with low loads of nitrobenzene (NB) (microbial community were attributed to the different intermediate degradation products of NB in each layer. The strains identified in this study were potential candidates for purifying waste gas effluents containing NB. PMID:28114416

  18. Molecular dynamics study of nitrobenzene and 2-nitrophenyloctyl ether saturated with water

    OpenAIRE

    Jorge, Miguel; Gulaboski, Rubin; Pereira, Carlos M.; Cordeiro, M. Natália D. S.

    2006-01-01

    In this paper, results obtained from molecular dynamics (MD) simulations on the watersaturated organic liquids nitrobenzene (NB) and 2-nitrophenyloctyl ether (NPOE) are presented. Both solvents are extremely important in many areas of chemistry, and they are seen as the most promising successors of n-octanol for ion transfer studies at the liquid–liquid interface. Thermodynamic (mass density, enthalpy of vaporization), structural (radial distribution functions) and dynamic (dif...

  19. Pathways of nitrobenzene degradation in horizontal subsurface flow constructed wetlands: Effect of intermittent aeration and glucose addition.

    Science.gov (United States)

    Kirui, Wesley K; Wu, Shubiao; Kizito, Simon; Carvalho, Pedro N; Dong, Renjie

    2016-01-15

    Intermittent aeration and addition of glucose were applied to horizontal subsurface flow constructed wetlands in order to investigate the effect on pathways of nitrobenzene (NB) degradation and interactions with microbial nitrogen and sulphur transformations. The experiment was carried out in three phases A, B and C consisting of different NB loading and glucose dosing. For each phase, the effect of aeration was assessed by intermittently aerating one wetland and leaving one unaerated. Regardless of whether or not the wetland was aerated, at an influent NB concentration of 140 mg/L, both wetlands significantly reduced NB to less than 2 mg/L, a reduction efficiency of 98%. However, once the influent NB concentration was increased to 280 mg/L, the aerated wetland had a higher removal performance 82% compared to that of the unaerated wetland 71%. Addition of glucose further intensified the NB removal to 95% in the aerated wetlands and 92% in the unaerated. Aeration of wetlands enhanced NB degradation, but also resulted in higher NB volatilization of 6 mg m(-2) d(-1). The detected high concentration of sulphide 20-60 mg/L in the unaerated wetland gave a strong indication that NB may act as an electron donor to sulphate-reducing bacteria, but this should be further investigated. Aeration positively improved NB removal in constructed wetlands, but resulted in higher NB volatilization. Glucose addition induced co-metabolism to enhance NB degradation.

  20. [Effect of background constituents on the degradation of trace nitrobenzene in aqueous solution by catalytic ozonation].

    Science.gov (United States)

    Sun, Zhi-zhong; Zhao, Lei; Ma, Jun

    2006-02-01

    Effect of background constituents on the catalytic ozonation of nitrobenzene was investigated. Degradation rates of ozonation alone, ceramic honeycomb and modified ceramic honeycomb-catalyzed ozonation in tap water increased by 4.90%, 2.47% and 5.12% than those in distilled water respectively. The removal rate of ozonation alone increased by 6.25% with the increase of the concentration of magnesium ion (0 to approximately 8 x mg x L(-1)), but those of other two processes decreased by 11.41% and 17.64%, respectively, under the same experimental condition. Degradation efficiency of ozonation alone, ceramic honeycomb and modified ceramic honeycomb-catalyzed ozonation decreased by 4.42%, 9.38% and 12.24%, respectively, with the increase of the concentration of chloride ion (0 to approximately 40 mg x L(-1)). At the lower concentration, humic acid could accelerate the degradation of nitrobenzene, however, the reaction was retarded at higher concentrations of humic acid. The experiment also studied the influences of the applied ozone and initial concentration of nitrobenzene.

  1. St. Vicent Ferrer’s Catalán sermon on St. Martin of Tours

    Directory of Open Access Journals (Sweden)

    Ferreiro, Alberto

    2013-12-01

    Full Text Available One of the most widely venerated saints in the Middle Ages was St. Martin of Tours whose cult continues to this day in many parts of the world. In the Middle Ages, he became as popular as other major saints such as Thomas Becket, Santiago de Compostela and the Virgin Mary. St. Martin’s cult became very prominent in the Iberian Peninsula before and after the emergence of the cult of Santiago de Compostela. In St. Vicent Ferrer’s voluminous sermons this one in Catalán is dedicated to this most venerated Gallic saint. The most important late antique and early medieval sources that form the background of this sermon are by Sulpicius Severus- the Gallus and Vita Sancti Martini. In the high Middle Ages, however, his cult was popularized through the Legenda Aurea written by the Dominican Jacobus of Voragine, who synthesized Sulpicius’ two works on St. Martin. Moreover, St. Vicent preached not to make any major doctrinal breakthroughs- his main interest was to evangelize, not to write academic theology- he nevertheless exhibited great creativity. The object of this study is St. Vicent’s Catalán sermon Alius Sermo Sancti Martini, CXXXIV.Uno de los santos más venerados en la edad media fue San Martín de Tours, cuyo culto continúa hasta hoy en muchas partes del mundo. En la edad media, se hizo tan popular como otros grandes Santos: Thomas Becket, Santiago de Compostela y la Virgen María. El culto de San Martín se hizo prominente en la Península Ibérica antes y después de la aparición del culto a Santiago de Compostela. En los sermones voluminosos de San Vicente Ferrer esta uno en Catalán que está dedicado a este santo tan venerado de Galia. Las fuentes más importantes procedentes de la antigu.edad tardía y principios medievales que forma el fondo de este sermón son Gallus y la Vita Sancti Martini de Sulpicio Severo. Sin embargo, en la alta edad media, su culto se popularizó a través de la Legenda Aurea escrita por el dominico

  2. L'Ètica nicomaquea en un compendi català del segle XV

    OpenAIRE

    Cuenca Almenar, Salvador

    2012-01-01

    Aquesta edició del Llibre de monàstica o ètica d"Aristòtil, realitzada a partir de l"únic manuscrit conegut: Biblioteca de Catalunya ms. 296, ofereix la primera publicació moderna d"aquest compendi català redactat probablement al segon terç del segle XV. Amb aquesta edició, volem contribuir a eixamplar el coneixement sobre l"ús del vernacle en la difusió escrita i en la docència filosòfica al segle XV. Així mateix, aquesta primera edició ens proveeix d"una font primigènia per a conèixer el lè...

  3. Gorceixite from Catalão, Goiás, Brazil: Rietveld Crystal Structure Refinement

    Directory of Open Access Journals (Sweden)

    Viviane Carillo Ferrari

    2007-10-01

    Full Text Available Gorceixite is an abundant aluminum phosphate in Brazilian laterite phosphate ores and is one of the most importantgangue minerals. Catalão I mine, Goiás, Brazil, one of the biggest phosphate mines in Brazil, contains great amounts ofgorceixite, whose structural formula, as suggested by microprobe analysis, is (Ba0.76Ca0.19Sr0.10Ce0.01Σ1.06(Al2.74Fe3+0.25Σ2.99(P0.96Si0.03Σ0.99O4(PO3OH(OH6.02. Its crystal structure, rich in Ca, Sr, and Fe, was refined by the Rietveld method appliedto X-ray powder diffraction data for trigonal and monoclinic structural models. The statistical parameters for the two modelsare so similar that they do not allow clear distinction of which is the better structural model for gorceixite. The cell parametersobtained for the trigonal model, space group R3m, are a = 7.0791(3 Å, c = 17.089(1 Å, V = 741.68(7 Å3, Z = 3, and for themonoclinic model, space group Cm, a =12.195(8 Å, b = 7.040(5 Å, c = 7.055(5 Å, β = 125.19(5°, V = 495 Å3, Z = 2.A particular feature of the Catalão gorceixite is the replacement of some Al in the X-site by Fe3+, with minor distortions incrystallochemical sites. These features may alter physical-chemical mineral characteristics, such as density and heavy metalretention capacity.

  4. La crisis económica y el movimiento independentista catalán

    Directory of Open Access Journals (Sweden)

    Aura Daniela Guzman Ramirez

    2013-11-01

    Full Text Available La crisis económica ha tenido una fuerte repercusión en Europa, pero en España, al estar organizada como un régimen de autonomías y reconocer la existencia de tres nacionalidades históricas, tiene una expresión particular. En el caso específico de una de ellas, Cataluña, la crisis se está expresando en un creciente fortalecimiento del movimiento independentista. En vista de la actualidad de la problemática y de las últimas manifestaciones masivas por la independencia catalana, este artículo ha hecho un seguimiento –a través de la prensa cotidiana– a la crisis en Cataluña y su relación con el movimiento independentista, y a la creciente polarización política entre el gobierno central español y el gobierno catalán en los últimos meses. Expresión concreta del pulso independentista es el llamado desde el partido de gobierno catalán (CiU y su “socio” en el gobierno (ERC, pero también a través de manifestaciones de la población, a un referendo para el 9 de noviembre de 2014 con dos preguntas centrales: “¿Quiere que Cataluña se convierta en un Estado? En caso afirmativo, ¿quiere que Cataluña sea un Estado independiente?” Empero, esta dinámica tiene su significado político más neurálgico en el cuestionamiento al régimen de transición instaurado durante el proceso democratizador en la década de los setenta. ¿Quo vadis España?

  5. St. Vicent Ferrer’s Catalán Sermon on Saint Mary Magdalene

    Directory of Open Access Journals (Sweden)

    Ferreiro, Alberto

    2010-06-01

    Full Text Available Vicent Ferrer is without question one of the most compelling and prolific Dominican preachers of the late Middle Ages. Although his preaching mission transpired in many places he especially carried out much of it in France. In France we witness, particularly in Provence, the emergence of the cult of Mary Magdalene that was vigorously promoted by the Dominicans. Vicent Ferrer not surprisingly dedicated this Catalán sermon to Mary Magdalene whom he proposed as a model of the Imitatio Christi for all Christians to follow, not just women in particular. This article seeks to situate this sermon in its late medieval context in order to unpack the theological and moral messages that Vicent sought to convey to his audience.

    Vicente Ferrer es, sin duda, uno de los predicadores dominicos más atractivos y prolíficos del bajo medievo. A pesar de que su misión de predicación se produjo en muchos lugares, gran parte de esa misión se llevó a cabo especialmente en Francia. En Francia, particularmente en la Provenza, somos testigos del surgimiento del culto a María Magdalena, promovido vigorosamente por los dominicos. No es sorprendente, Vicente Ferrer dedicó este sermón en catalán a María Magdalena, a quien propuso como modelo de la Imitatio Christi, para que todos los cristianos lo siguieran, no sólo para las mujeres en particular. Este artículo pretende situar este sermón en su contexto del siglo XIV con el fin de descomprimir los mensajes teológicos y morales que Vicente trató de transmitir a su público.

  6. Solar-driven thermo- and electrochemical degradation of nitrobenzene in wastewater: Adaptation and adoption of solar STEP concept.

    Science.gov (United States)

    Gu, Di; Shao, Nan; Zhu, Yanji; Wu, Hongjun; Wang, Baohui

    2017-01-05

    The STEP concept has successfully been demonstrated for driving chemical reaction by utilization of solar heat and electricity to minimize the fossil energy, meanwhile, maximize the rate of thermo- and electrochemical reactions in thermodynamics and kinetics. This pioneering investigation experimentally exhibit that the STEP concept is adapted and adopted efficiently for degradation of nitrobenzene. By employing the theoretical calculation and thermo-dependent cyclic voltammetry, the degradation potential of nitrobenzene was found to be decreased obviously, at the same time, with greatly lifting the current, while the temperature was increased. Compared with the conventional electrochemical methods, high efficiency and fast degradation rate were markedly displayed due to the co-action of thermo- and electrochemical effects and the switch of the indirect electrochemical oxidation to the direct one for oxidation of nitrobenzene. A clear conclusion on the mechanism of nitrobenzene degradation by the STEP can be schematically proposed and discussed by the combination of thermo- and electrochemistry based the analysis of the HPLC, UV-vis and degradation data. This theory and experiment provide a pilot for the treatment of nitrobenzene wastewater with high efficiency, clean operation and low carbon footprint, without any other input of energy and chemicals from solar energy.

  7. Influencing mechanism of temperature on the degradation of nitrobenzene in aqueous solution by ceramic honeycomb catalytic ozonation.

    Science.gov (United States)

    Zhao, Lei; Ma, Jun; Sun, Zhizhong; Liu, Huiling

    2009-08-15

    The heterogeneous catalytic ozonation of nitrobenzene in aqueous solution has been carried out at different reaction temperatures in a semi-continuous batch reactor where ceramic honeycomb has been used as a catalyst. The experimental results indicated that the presence of ceramic honeycomb catalyst significantly improved the degradation efficiency of nitrobenzene compared to the results from non-catalytic ozonation, and the adsorption of nitrobenzene on the catalytic surface has no significant effect on its degradation efficiency. The degradation of nitrobenzene followed the pseudo-first-order kinetic model in both the processes of ozone alone and ozone/ceramic honeycomb. With the increase of reaction temperature from 278K to 328K, the degradation efficiency of nitrobenzene, the reaction rate constants, the utilization efficiency of ozone, the formation of hydroxyl radicals (*OH) and the removal of total organic carbon (TOC) all increased in the process of ozone/ceramic honeycomb. The enhancement of reaction rate constant and the enhancement of *OH formation exhibited a good correlation in the reaction temperature scope of 278-328K.

  8. Solar-driven thermo- and electrochemical degradation of nitrobenzene in wastewater: Adaptation and adoption of solar STEP concept

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Di; Shao, Nan; Zhu, Yanji; Wu, Hongjun; Wang, Baohui, E-mail: wangbh@nepu.edu.cn

    2017-01-05

    Highlights: • STEP for NB treatment was established without input of energy and chemicals. • Treatment of NB was theoretically and experimentally studied by STEP. • The results demonstrated that STEP is more efficient than classical AOPs. • The mechanism of STEP was illustratively presented for NB wastewater. - Abstract: The STEP concept has successfully been demonstrated for driving chemical reaction by utilization of solar heat and electricity to minimize the fossil energy, meanwhile, maximize the rate of thermo- and electrochemical reactions in thermodynamics and kinetics. This pioneering investigation experimentally exhibit that the STEP concept is adapted and adopted efficiently for degradation of nitrobenzene. By employing the theoretical calculation and thermo-dependent cyclic voltammetry, the degradation potential of nitrobenzene was found to be decreased obviously, at the same time, with greatly lifting the current, while the temperature was increased. Compared with the conventional electrochemical methods, high efficiency and fast degradation rate were markedly displayed due to the co-action of thermo- and electrochemical effects and the switch of the indirect electrochemical oxidation to the direct one for oxidation of nitrobenzene. A clear conclusion on the mechanism of nitrobenzene degradation by the STEP can be schematically proposed and discussed by the combination of thermo- and electrochemistry based the analysis of the HPLC, UV–vis and degradation data. This theory and experiment provide a pilot for the treatment of nitrobenzene wastewater with high efficiency, clean operation and low carbon footprint, without any other input of energy and chemicals from solar energy.

  9. Contribution to the thermodynamics of 1-(2-thiazolylazo-2-naphthol in the water-nitrobenzene extraction system

    Directory of Open Access Journals (Sweden)

    PETR VANURA

    2000-08-01

    Full Text Available General relations among thermodynamic parameters characterizing chemical equilibria including species H2A+, HA, H+ and A- in both phases of a two-phase water-nitrobenzene extraction system have been derived. From the extraction measurements, the equilibrium distribution constant of electroneutral 1-(2-thiazolylazo-2-naphthol (TAN, HA between the nitrobenzene and aqueous phases has been determined: log KD(HA = 3.90±0.02. By using this value and further known constants and applying the mentioned relations, the following values of dissociation constants of TAN in nitrobenzene saturated with water have been calculated for a temperature of 25°C: pKdnb(H2A+ = -log Kdnb(H2A+ = 4.9 and pKdnb(HA = -log Kdnb(HA = 16.5.

  10. Effects of nitrobenzene concentration and hydraulic retention time on the treatment of nitrobenzene in sequential anaerobic baffled reactor (ABR)/continuously stirred tank reactor (CSTR) system.

    Science.gov (United States)

    Kuscu, Ozlem Selcuk; Sponza, Delia Teresa

    2009-04-01

    The effects of increasing nitrobenzene (NB) concentrations and hydraulic retention times (HRT) on the treatment of NB were investigated in a sequential anaerobic baffled reactor (ABR)/aerobic completely stirred tank reactor (CSTR) system. In the first step of the study, the maximum COD removal efficiencies were found as 88% and 92% at NB concentrations varying between 30 mg L(-1) and 210 mg L(-1) in ABR. The minimum COD removal efficiency was 79% at a NB concentration of 700 mg L(-1). The removal efficiency of NB was nearly 100% for all NB concentrations in the ABR reactor. The methane gas production and the methane gas percentage remained stable (1500 mL day(-1) and 48-50%, respectively) as the NB concentration was increased from 30 to 210 mg L(-1). In the second step of the study it was found that as the HRT decreased from 10.38 days to 2.5 days the COD removal efficiencies decreased slightly from 94% to 92% in the ABR. For maximum COD and NB removal efficiencies the optimum HRT was found as 2.5 days in the ABR. The total COD removal efficiency was 95% in sequential anaerobic (ABR)/aerobic (CSTR) reactor system at a minimum HRT of 1 day. When the HRT was decreased from 10.38 days to 1 day, the methane percentage decreased from 42% to 29% in an ABR reactor treating 100 mg L(-1) NB. Nitrobenzene was reduced to aniline under anaerobic conditions while aniline was mineralized to catechol with meta cleavage under aerobic conditions.

  11. Intimately coupling of photolysis accelerates nitrobenzene biodegradation, but sequential coupling slows biodegradation

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lihui [Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234 (China); Zhang, Yongming, E-mail: zhym@shnu.edu.cn [Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234 (China); Bai, Qi; Yan, Ning; Xu, Hua [Department of Environmental Science and Engineering, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234 (China); Rittmann, Bruce E. [Swette Center for Environmental Biotechnology, Biodesign Institute, Arizona State University, Tempe, AZ 85287-5701 (United States)

    2015-04-28

    Highlights: • Intimately coupled UV photolysis accelerated nitrobenzene biodegradation. • NB biodegradation was slowed by accumulation of nitrophenol. • Oxalic acid was a key product of UV photolysis. • Oxalic acid accelerated biodegradation of nitrobenzene and nitrophenol by a co-substrate effect. • Intimate coupling of UV and biodegradation accentuated the benefits of oxalic acid. - Abstract: Photo(cata)lysis coupled with biodegradation is superior to photo(cata)lysis or biodegradation alone for removal of recalcitrant organic compounds. The two steps can be carried out sequentially or simultaneously via intimate coupling. We studied nitrobenzene (NB) removal and mineralization to evaluate why intimate coupling of photolysis with biodegradation was superior to sequential coupling. Employing an internal circulation baffled biofilm reactor, we compared direct biodegradation (B), biodegradation after photolysis (P + B), simultaneous photolysis and biodegradation (P&B), and biodegradation with nitrophenol (NP) and oxalic acid (OA) added individually and simultaneously (B + NP, B + OA, and B + NP + OA); NP and OA were NB’s main UV-photolysis products. Compared with B, the biodegradation rate P + B was lower by 13–29%, but intimately coupling (P&B) had a removal rate that was 10–13% higher; mineralization showed similar trends. B + OA gave results similar to P&B, B + NP gave results similar to P + B, and B + OA + NP gave results between P + B and P&B, depending on the amount of OA and NP added. The photolysis product OA accelerated NB biodegradation through a co-substrate effect, but NP was inhibitory. Although decreasing the UV photolysis time could minimize the inhibition impact of NP in P + B, P&B gave the fastest removal of NB by accentuating the co-substrate effect of OA.

  12. High-pressure behavior of solid nitrobenzene: Combined Raman spectroscopy and DFT-D calculations study

    Science.gov (United States)

    Wang, Wen-Peng; Liu, Fu-Sheng; Liu, Qi-Jun; Zhang, Lin-Ji; Wang, Yi-Gao; Liu, Zheng-Tang

    2016-09-01

    Nitrobenzene (NB), a simplest structure of the aromatic nitro compounds, was investigated as a model for understanding structural properties in nitro derivatives of benzene and anilines. Using the Raman spectroscopic technique, the vibrational modes of solid NB were examined under hydrostatic compression up to 10 GPa. The Raman spectra indicated that a subtle phase transition occurred around 5 GPa. Also, the dispersion corrected density functional theory (DFT-D) calculations were performed to provide further insight into pressure effects on the molecular geometry. The calculated data suggested that NB molecules were distorted, and molecular conformation was readjusted when the phase transition with vibrational changes took place under high-pressure.

  13. Critical fluctuations and noncritical relaxations of the nitrobenzene isooctane system near its consolute point

    Science.gov (United States)

    Khabibullaev, P. K.; Mirzaev, S. Z.; Kaatze, U.

    2008-06-01

    Ultrasonic attenuation spectra between 20 kHz and 3 GHz of the nitrobenzene-isooctane mixture of critical composition have been analyzed to show that they contain noncritical relaxation terms in addition to the critical term. The parameter values of the noncritical contributions obtained thereby are used in a re-evaluation of smallband attenuation data from the literature. These data, measured at a large number of temperatures near the critical, are most suitable for the determination of the scaling function in the critical dynamics. The procedure allows to verify the empirical scaling function of the Bhattacharjee-Ferrell dynamic scaling theory without an adjustable parameter.

  14. 4-Nitrobenzene Grafted in Porous Silicon: Application to Optical Lithography.

    Science.gov (United States)

    Tiddia, Mariavitalia; Mula, Guido; Sechi, Elisa; Vacca, Annalisa; Cara, Eleonora; De Leo, Natascia; Fretto, Matteo; Boarino, Luca

    2016-12-01

    In this work, we report a method to process porous silicon to improve its chemical resistance to alkaline solution attacks based on the functionalization of the pore surface by the electrochemical reduction of 4-nitrobenzendiazonium salt. This method provides porous silicon with strong resistance to the etching solutions used in optical lithography and allows the fabrication of tailored metallic contacts on its surface. The samples were studied by chemical, electrochemical, and morphological methods. We demonstrate that the grafted samples show a resistance to harsh alkaline solution more than three orders of magnitude larger than that of pristine porous silicon, being mostly unmodified after about 40 min. The samples maintained open pores after the grafting, making them suitable for further treatments like filling by polymers. Optical lithography was performed on the functionalized samples, and electrochemical characterization results are shown.

  15. Responses of a novel salt-tolerant Streptomyces albidoflavus DUT_AHX capable of degrading nitrobenzene to salinity stress.

    Science.gov (United States)

    Ai, Haixin; Zhou, Jiti; Lu, Hong; Guo, Jianbo

    2009-02-01

    A novel salt-tolerant strain DUT_AHX, which was capable of utilizing nitrobenzene (NB) as the sole carbon source, was isolated from NB-contaminated soil. Furthermore, it was identified as Streptomyces albidoflavus on the basis of physiological and biochemical tests and 16S ribosomal DNA (rDNA) sequence analysis. It can grow in the presence of NaCl up to 12% (w/v) or NB up to 900 mg/l in mineral salts basal (MSB) medium. The exogenously added osmoprotectants such as glycin, glutamic acid, proline, betaine and ectoine can improve growth of strain DUT_AHX in the presence of 10% (w/v) NaCl. NB-grown cells of strain DUT_AHX in modified MSB medium can degrade NB with the concomitant release of ammonia. Moreover, crude extracts of NB-grown strain DUT_AHX mainly contained 2-aminophenol 1,6-dioxygenase activity. These indicate that NB degradation by strain DUT_AHX might involve a partial reductive pathway. The proteins induced by salinity stress or NB were analyzed by native-gradient polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate (SDS)-PAGE. In NB-induced proteins de novo, 141 kDa protein on the native-gradient PAGE gel was excised and electroeluted. Furthermore, enzyme tests exhibit the 2-aminophenol 1,6-dioxygenase activity of purified 141 kDa protein is 11-fold that of the cell-free extracts. The exploitation of strain DUT_AHX in salinity stress will be a remarkable improvement in NB bioremediation and wastewater treatment in high salinity.

  16. Prevention of tri-nitrobenzene of sulfonic acid-induced colitis in chicken by using extract of Aloe vera

    Directory of Open Access Journals (Sweden)

    Motamed Elsayed Mahmoud

    Full Text Available Aim: Aloe vera, species of succulent plant in the genus Aloe, has multiple clinical activities and used routinely to accelerate wound healing. The present study was designed to investigate the anti-inflammatory effect of Aloe vera extracts (AVE in vitro and in vivo. Materials and Methods: The effect of crude AVE on inducible nitric oxide production by LPS/IFNg-stimulated cultured macrophages was evaluated. The therapeutic effect of administering crude Aloe vera extracts (100 mg/kg b.w. on the development of tri-nitrobenzene of sulfonic acid (TNBS-induced colitis (40 mg/kg b. w. in chicken was also investigated. Chicken is a valuable model for this purpose because it showed preference to bitter taste of Aloe vera. Diverse clinical pictures of the colitis including weight loss, diarrhea and histopathological changes were evaluated. Results: Nitrite production by LPS/IFNg-stimulated macrophages was maximally reduced by adding of AVE (100 μg/ml. This result suggests a direct inhibitory effect of AVE on the inflammatory cells. Chicks treated orally with AVE showed improvement of the histological signs with no inflammatory cell infiltrates and reduction of myeloperoxidase (MPO activities when compared with colitis control group. AVE pretreatment ameliorated significantly the clinical and histopathological severity of the TNBS-induced colitis; decreased body weight loss and diarrhea and increased survival. Conclusion: It was concluded that oral administration of AVE represents a valuable therapeutic approach for the treatment of colitis in chicken. [Vet. World 2012; 5(8.000: 469-476

  17. Anticorpos catalíticos e suas aplicações em biotecnologia - doi: 10.5102/ucs.v10i2.1583

    Directory of Open Access Journals (Sweden)

    Luciana Martins Macedo

    2012-12-01

    Full Text Available Características peculiares como a alta especificidade dos anticorpos e o eficiente poder catalítico das enzimas, têm despertado um grande interesse em grupos de pesquisa científica no que diz respeito às possíveis reações obtidas pela junção dessas duas moléculas. O objetivo deste trabalho foi realizar uma revisão bibliográfica sobre a constituição e obtenção dos anticorpos catalíticos e suas potenciais aplicações em biotecnologia. A tecnologia de anticorpos catalíticos já demonstrou a capacidade dessas moléculas em mediar diversas reações e vem abrindo relevantes possibilidades de aplicações em áreas industriais, agrícolas, e biotecnológicas. Aliada à prática médica os anticorpos catalíticos são grande promessa para fins diagnósticos e terapêuticos desde a destruição de células cancerígenas e microrganismos, até a elaboração de vacinas catalíticas para as mais diversas finalidades como a desintoxicação definitiva de pacientes com dependência química.

  18. The effects of flow rate and concentration on nitrobenzene removal in abiotic and biotic zero-valent iron columns.

    Science.gov (United States)

    Yin, Weizhao; Wu, Jinhua; Huang, Weilin; Li, Yongtao; Jiang, Gangbiao

    2016-08-01

    This study investigated the effects of varying nitrobenzene (NB) loadings via increasing flow rate or influent NB concentration mode on the removal efficiency in zero-valent iron (ZVI) columns sterilized (abiotic) or preloaded with acclimated microorganisms (biotic). It was shown that physical sequestration via adsorption/co-precipitation and reductive transformation of NB to aniline (AN) were the two major mechanisms for the NB removal in both abiotic and biotic ZVI columns. The NB removal efficiency decreased in both columns as the flow rate increased from 0.25 to 1.0mLmin(-1) whereas the AN recovery increased accordingly, with relatively high AN recovery observed at the flow rate of 1.0mLmin(-1). At the constant flow rate of 0.5mLmin(-1), increasing influent NB concentration from 80 to 400μmolL(-1) resulted in decreasing of the overall NB removal efficiency from 79.5 to 48.6% in the abiotic column and from 85.6 to 62.5% in the biotic column. The results also showed that the sequestration capacity and chemical reduction capacity were respectively 72% and 157.6% higher in the biotic column than in the abiotic column at the same tested hydraulic conditions and NB loadings. The optimal flow rates and influent NB concentrations were at 0.5mLmin(-1) and 80μmolL(-1) for the abiotic column and 2.0mLmin-1 and 240μmolL(-1) for the biotic column, respectively. This study indicated that microorganisms not only enhanced overall reduction of NB, but also facilitated NB sequestration within the porous media and that the optimal loading conditions for overall removal, sequestration, and reduction of NB may be different. Optimal operation conditions should be found for preferred sequestration or transformation (or both) of the target contaminants to meet different goals of groundwater remediation with the ZVI-PRB systems.

  19. Stability analysis of alkaline nitrobenzene-containing wastewater by a catalyzed Fe-Cu treatment process

    Institute of Scientific and Technical Information of China (English)

    FAN Jinhong; XU Wenying; GAO Tingyao; MA Luming

    2007-01-01

    Iron and copper bimetallic system (catalyzed Fe-Cu process) is a promising technology for alkaline nitrobenzene-containing wastewater treatment.However,little is currently known about the changes of treatment efficiency with time going.This research investigated the long-term performance of the catalyzed Fe-Cu process to reduce nitrobenzene (NB) in alkaline wastewater.In addition,the changes of the metal surfaces morphologies and matters before and after the reaction were analyzed by scanning electron microscopy (SEM) in conjunction with energydispersion spectroscopy (EDS) and X-ray diffraction spectroscopy (XRD).The results showed that the surface properties of copper almost remained unchanged after weeks of operation,which spelled its strong chemical stability and resistance to poisoning.Moreover,the results indicated that there were two reasons for the treatment efficiency decreasing with time.One was the gradual iron element consumption due to corrosion.The other was iron reactivity weakened due to the precipitates accumulation on the surfaces that were mainly Fe3O4 and FeCO.

  20. Synthesis and Characterization of Cerium Doped Titanium Catalyst for the Degradation of Nitrobenzene Using Visible Light

    Directory of Open Access Journals (Sweden)

    Padmini Ellappan

    2014-01-01

    Full Text Available Cerium doped catalyst was synthesized using Titanium isopropoxide as the Titanium source. The metal doped nanoparticles semiconductor catalyst was prepared by sol-sol method with the sol of Cerium. The synthesized catalyst samples were characterized by powder X-ray diffraction, BET surface area, thermogravimetric analysis (TGA, scanning electron microscopy (SEM, and UV-vis diffuse reflectance measurements (DRS and compared with undoped TiO2 catalyst. The photocatalytic activity of the sample was investigated for the decomposition of nitrobenzene (NB using visible light as the artificial light source. Cerium doped catalyst was found to have better degradation of nitrobenzene owing to its shift in the band gap from UV to visible region as compared to undoped TiO2 catalyst. The operational parameters were optimized with catalyst dosage of 0.1 g L−1, pH of 9, and light intensity of 500 W. The degradation mechanism followed the Langmuir Hinshelwood kinetic model with the rate constant depending nonlinearly on the operational parameters as given by the relationship Kapp (theoretical = 2.29 * 10−4 * Intensity0.584 * Concentration−0.230 * Dosage0.425 * pH0.336.

  1. Analyses of nitrobenzene,benzene and aniline in environmental water samples by headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry

    Institute of Scientific and Technical Information of China (English)

    CHEN Ming; YIN Yongguang; TAI Chao; ZHANG Qinghua; LIU Jiyan; HU Jingtian; JIANG Guibin

    2006-01-01

    A headspace solid phase microextraction coupled with gas chromatography mass spectrometry (HS-SPME/GC-MS) method was established for analyzing nitrobenzene, benzene and aniline in environmental water samples simultaneously.Factors affecting extraction efficiency (SPME fiber selection, acidity, temperature, salt addition, extraction time, headspace, etc) were verified. Under optimal extraction conditions, the detection limits are 0.50, 0.11 and 1.00 μg/L for nitrobenzene, benzene and aniline, respectively. The results indicate that this method is capable of making sensitive and accuracy analyses on nitrobenzene, benzene and aniline in environmental water samples.

  2. Solvent extraction of Li+, H3O+ and NH4+ into nitrobenzene by using sodium dicarbollylcobaltate and calix[4]arene-bis(t-octylbenzo-18-crown-6)

    Energy Technology Data Exchange (ETDEWEB)

    Makrlik, Emanuel [Czech University of Life Sciences, Prague, Kamy´cká; Selucky, P. [Nuclear Research Institute, Rez, Czech Republic; Vanura, Petr [Institute of Chemical Technology, Prague, Czech Republic; Moyer, Bruce A [ORNL

    2013-01-01

    From extraction experiments and c-activity measurements, the exchange extraction constants corresponding to the general equilibrium M+ (aq) + NaL+ (nb) , ML+ (nb) + Na+ (aq) taking place in the two-phase water nitrobenzene system (M+ = Li+, H3O+, NH+4; L = calix[4]arene-bis(t-octylbenzo-18-crown-6); aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Furthermore, the stability constants of the ML+ complexes in nitrobenzene saturated with water were calculated; they were found to increase in the following cation order: zH3O+ < Li+ < NH+4.

  3. Anticorpos catalíticos e suas aplicações em biotecnologia - doi: 10.5102/ucs.v10i2.1583

    OpenAIRE

    2012-01-01

    Características peculiares como a alta especificidade dos anticorpos e o eficiente poder catalítico das enzimas, têm despertado um grande interesse em grupos de pesquisa científica no que diz respeito às possíveis reações obtidas pela junção dessas duas moléculas. O objetivo deste trabalho foi realizar uma revisão bibliográfica sobre a constituição e obtenção dos anticorpos catalíticos e suas potenciais aplicações em biotecnologia. A tecnologia de anticorpos catalíticos já demonstrou a capaci...

  4. Un vocabulari pornogràfic francès-català inèdit

    Directory of Open Access Journals (Sweden)

    Joan Puigmalet

    2014-06-01

    Full Text Available Antoni Bulbena Tosell és autor d’un manuscrit, i inèdit, vocabulari pornogràfic francèscatalà català-francès, la Flora pornogràfica francesa: suplement al argot francès / Flore pornographique catalane: supplément à l’argot catalan. És una obra d’aproximadament l’any 1921 que, per la seva temàtica, ell mateix reservava per a no publicar-se. Bulbena és autor d’una discutida obra lingüística, entre la qual trobem diferents diccionaris, alguns d’ells entre el català i el francès. El darrer que publicà és el Diccionari de les lléngues francesa & catalana / Dictionnaire catalan-français (1921 que inclou dos apèndixs, un «Vocabulari d’argot francès» i un «Vocabulari d’argot catalan». La Flora és, així, un suplement al lèxic pornogràfic d’aquest diccionari. Per altra banda, el títol de Flora pornogràfica sembla fer referència a una obra de la lexicografia francesa que recull mots obscens presents a obres d’Emile Zola i altres escriptors naturalistes, La flore pornographique (1883, d’Ambroise Macrobe. Els mots d’argot sexual de la Flora, amb un especial focus temàtic en la prostitució, tenen interès lingüístic i cultural tant per a la llengua catalana com per a la llengua francesa. Antoni Bulbena Tosell is the author of an unpublished, pornographic vocabulary FrenchCatalan Catalan-French, a manuscript called the Flora pornogràfica francesa: suplement al argot francès / Flore pornographique catalane: supplément à l’argot catalan. It was written around 1921 and reserved for not being published. Bulbena is the author of a controversial linguistic work, among which are various dictionaries, some of them between Catalan and French. The latest is the Diccionari de les lléngues francesa & catalana / Dictionnaire catalan-français (1921, that includes two appendixes, a «Vocabulari d’argot francès» and a «Vocabulari d’argot catalan». The Flora is thus a pornographic supplement to the

  5. Conversión catalítica de metanol sobre catalizadores ácidos de carbono

    OpenAIRE

    Valero-Romero, Mª José; Calvo-Muñoz, Elisa Mª; Ruiz-Rosas, Ramiro; Bedia, Jorge; Rodríguez-Mirasol, José; Cordero, Tomás

    2013-01-01

    En las últimas décadas, el estudio y desarrollo de carbones activos como catalizadores o soportes catalíticos se ha incrementado enormemente debido a las ventajas derivadas de su elevada capacidad adsorbente, inercia y estabilidad química, una química superficial versátil y elevada resistencia mecánica. Además, su preparación a partir de residuos biomásicos supone un beneficio no sólo económico, sino también medioambiental, que puede resultar clave en el contexto energético e industrial actua...

  6. Estudio experimental del aprovechamiento del calor residual de un MACI para generar hidrógeno catalíticamente

    OpenAIRE

    Rejas García, Albert

    2014-01-01

    A lo largo de este proyecto se realiza el estudio de la posibilidad de la utilización de energía residual, concretamente el calor disipado por los gases de escape de un motor de combustión, para el reformado catalítico de hidrógeno. Es decir, la obtención de un vector energético a partir de energía no aprovechada, lo que significa un aumento de la eficiencia del sistema. Para realizar el reformado se han valorado diferentes catalizadores: uno de cobalto y uno de rodio-paladio, así...

  7. Cambio de los coeficientes de transferencia en reactores de desintegración catalítica

    OpenAIRE

    E. F. Villafuerte Macías; R. Aguilar López; R. Maya Yescas

    2003-01-01

    Debido a la generación de moléculas a lo largo de los reactores de lecho transportado durante la desintegración catalítica de hidrocarburos pesados, disminuye la densidad y se incrementa la velocidad de la mezcla reactiva. Esta situación provoca un cambio en dirección axial de la velocidad relativa del catalizador respecto a la de la mezcla reactiva evaporada y, consecuentemente, variación continua de los coeficientes de transferencia de masa y calor entre la fase gaseosa y la superficie del ...

  8. La Estación del Norte: un ejemplo de rehabilitación del modernismo catalán

    OpenAIRE

    Maristany Carreras, Jordi; Calderón Valdiviezo, Lucrecia Janneth; Albareda Valls, Albert

    2013-01-01

    El modernismo catalán es un periodo que se caracteriza por un tratamiento exquisito de los materiales de construcción. A cambio, éstos han sido motivo de preocupación constante en su rehabilitación posterior provocada por las deficientes uniones entre los distintos materiales y el incorrecto tratamiento del acero como material ornamental. Uno de los edificios más representativos de este periodo es la “Estación del Norte de Barcelona”. Inicialmente, construida con la intención de albergar en s...

  9. Conversión catalítica de metanol sobre catalizadores ácidos de carbono

    OpenAIRE

    Valero-Romero, Mª José; Calvo-Muñoz, Elisa Mª; Ruiz-Rosas, Ramiro; Bedia, Jorge; Rodríguez-Mirasol, José; Cordero, Tomás

    2013-01-01

    En las últimas décadas, el estudio y desarrollo de carbones activos como catalizadores o soportes catalíticos se ha incrementado enormemente debido a las ventajas derivadas de su elevada capacidad adsorbente, inercia y estabilidad química, una química superficial versátil y elevada resistencia mecánica. Además, su preparación a partir de residuos biomásicos supone un beneficio no sólo económico, sino también medioambiental, que puede resultar clave en el contexto energético e industrial actua...

  10. Síntesis y aplicaciones de nuevos sistemas catalíticos soportados sobre matrices poliméricas

    OpenAIRE

    Díz Martínez, Paula María

    2016-01-01

    Las reacciones catalizadas por cobre constituyen herramientas sintéticas excepcionales dentro de la Química Orgánica actual. El trabajo descrito en la presente Tesis Doctoral se enmarca en un proyecto general, que desarrolla ComBioMed, encaminado a explotar las ventajas de los reactivos soportados en el descubrimiento preliminar de fármacos. En el marco de este trabajo se han desarrollado nuevos sistemas catalíticos basados en cobre soportados sobre diferentes matrices poliméri...

  11. Relación entre variables morfométricas en canales de la raza equina “Cavall pirinenc català” - Relationships between morphometric values in “Cavall pirinenc català” equine breed carcasses

    Directory of Open Access Journals (Sweden)

    Parés i Casanova, Pere-Miquel.

    2010-11-01

    Full Text Available ResumenSe analizaron 27 canales de potro (19 machos y 8 hembras de la raza“Cavall Pirinenc Català”. Las variables obtenidas fueron la anchura depecho y de cadera, la longitud de canal y el peso de la canal caliente, que arrojaron unos coeficientes de variación de 1,2 a 11,3%. La anchura de la cadera y la longitud de la canal presentaron una distribución no normal. Las medidas lineales de la anchura de pecho mostraron una correlación positiva baja con el peso de la cana(r=0,476. Este trabajo muestra que deben elegirse otras variablesmorfométricas para la predicción de cortes valiosos en canales equinas.SummaryA test is conducted with 27 young horses (19 males and 8 femalesbelonging to “Cavall Pirinenc Català” breed. Chest and hip width,carcass length and hot carcass weight exhibit variation coefficients that ranged from 1.2 to 11.3 percent. Hip width and carcass length has no normal distribution. Linear measurements of chest width has a low, positive relationship with hot carcass weight (r=0.476. This study shows that other morphometric traits must be used for predictingvaluable cuts in equine carcasses.

  12. The influence of different irradiation sources on the treatment of nitrobenzene

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Miguel [Universidad de Los Andes, Escuela Basica de Ingenieria, La Hechicera, Merida (Venezuela); Timokhin, Vitaliy [Department of Physical Chemistry, Institute of Physical Chemistry, National Academy of Sciences of Ukraine, 3a Naukova Street, 79053 Lviv (Ukraine); Michl, Florian; Contreras, Sandra; Gimenez, Jaime; Esplugas, Santiago [Department d' Enginyeria Quimica i Metallurgia, Universitat de Barcelona, Marti i Franques 1, 08028 Barcelona (Spain)

    2002-11-15

    This work describes the influence of light on the treatment of nitrobenzene (NB) in aqueous solutions. Three different experimental devices were used to perform a detailed study: a photoreactor with four low-pressure mercury lamps ({lambda}=253.7nm), a tubular photoreactor with a polychromatic Xe lamp (290<{lambda}<1200nm), and finally a solar reactor (sunlight). TOC analyses were performed in order to monitor and compare the extent of these processes, each of them being performed with one of the three different sources of light. The influence of Fe(II), Fe(III), H{sub 2}O{sub 2}, and light on the mineralization of NB in aqueous solutions was also studied. The successful use of sunlight as a source of energy and its effectiveness regarding Fenton processes as well as direct photolysis in the treatment of NB are presented.

  13. Charge transfer across the water/nitrobenzene interface bythree-electrode system

    Institute of Scientific and Technical Information of China (English)

    YUAN; Yi; (袁艺); GAO; Zhao; (高(目目空); ); ZHANG; Meiqin; (张美芹); ZHANG; Zhiquan; (张志权); SHAO; Yuanhua; (邵元华)

    2002-01-01

    A droplet of aqueous solution containing a certain molar ratio of redox couple is first attached onto a platinum electrode surface, then the resulting drop electrode is immersed into the organic solution containing very hydrophobic electrolyte. Combined with reference and counter electrodes, a classical three-electrode system has been constructed. Ion transfer (IT) and electron transfer (ET) are investigated systematically using three-electrode voltammetry. Potassium ion transfer and electron transfer between potassium ferricyanide in the aqueous phase and ferrocene in nitrobenzene are observed with potassium ferricyanide/potassium ferrocyanide as the redox couple. Meanwhile, the transfer reactions of lithium, sodium, potassium, proton and ammonium ions are obtained with ferric sulfate/ferrous sulfate as the redox couple. The formal transfer potentials and the standard Gibbs transfer energy of these ions are evaluated and consistent with the results obtained by a four-electrode system and other methods.

  14. Microbial Community in a Biofilter for Removal of Low Load Nitrobenzene Waste Gas.

    Science.gov (United States)

    Zhai, Jian; Wang, Zhu; Shi, Peng; Long, Chao

    2017-01-01

    To improve biofilter performance, the microbial community of a biofilter must be clearly defined. In this study, the performance of a lab-scale polyurethane biofilter for treating waste gas with low loads of nitrobenzene (NB) (biofilters were analysed by using Illumina MiSeq high-throughput sequencing. The results showed that NB waste gas was successfully degraded in the biofilter. High-throughput sequencing data suggested that the phylum Actinobacteria and genus Rhodococcus played important roles in the degradation of NB. The variations of the microbial community were attributed to the different intermediate degradation products of NB in each layer. The strains identified in this study were potential candidates for purifying waste gas effluents containing NB.

  15. [Effect of organic compounds on the degradation of nitrobenzene in aqueous solution by catalytic ozonation].

    Science.gov (United States)

    Zhao, Lei; Ma, Jun; Liu, Zheng-Qian; Sun, Zhi-Zhong; Hou, Yan-Jun

    2008-05-01

    We investigated the effects of organic compounds on the processes of ozonation alone and ceramic honeycomb-catalyzed ozonation for the degradation of nitrobenzene in aqueous solution, including formaldehyde, methanol, formic acid and dibutyl phthalate. The results indicated that degradation rate of ozonation alone and ceramic honeycomb-catalyzed ozonation decreased by 11.6% and 9.6% with the increase of the concentration of formaldehyde (0-12 mg x L(-1)). The degradation rates of the two processes both increased firstly and decreased subsequently with the increase of the concentration of methanol (0-16 mg x L(-1)). The degradation rate of ozonation alone reached the climax at the concentration of methanol 2 mg x L(-1), and that of ceramic honeycomb-catalyzed ozonation reached the culmination at the concentration of methanol 4 mg x L(-1) under the same experimental condition. With the increase of the concentration of formic acid (0-8 mg x L(-1)), the degradation rates also increased firstly and decreased subsequently, and those of ozonation alone and ceramic honeycomb-catalyzed ozonation reached the vertex, respectively, at the concentration of methanol 0.5 mg x L(-1) and 2 mg x L(-1). At the lower concentration, methanol and formic acid could accelerate the degradation of nitrobenzene, however, the reaction was retarded at higher concentrations of methanol and formic acid. The degradation rates of ozonation alone and ozonation/ceramic honeycomb both declined by 19.7% and 18.6% with the increase of the concentration of dibutyl phthalate (0-10 mg x L(-1)).

  16. Kernels para la clasificacíon de preguntas en español y catalán

    Directory of Open Access Journals (Sweden)

    David Tomás

    2009-12-01

    Full Text Available Este artículo presenta una aproximacíon a la clasificación automática de preguntas en español y catalán. El sistema de clasificación está basado en el algoritmo SVM y en el uso de diferentes funciones kernel, empleando únicamente características textuales superficiales que permiten la obtencíon de un sistema fácilmente adaptable a diferentes idiomas. Se ha realizado un estudio sobre el correcto a juste de parámetros de los kernels, la precisíon de los mismos, la definicíon de distintos vectores de características de aprendizaje y el rendimiento en función del idioma de trabajo. Adicionalmente, se ha experimentado con el algoritmo LIBLINEAR, aplicado aquí por vez primera a la tarea de clasificación de preguntas. Con este algoritmo, así como con los kernels definidos, se han obtenido valores de precisión por encima del 80 % para los dos idiomas tratados, superando a otros algoritmos tradicionales de clasificación. Para el entrenamiento y evaluación del sistema se ha desarrollado un corpus paralelo de 2.393 preguntas en inglés, español y catalán.

  17. Kernels para la clasificacíon de preguntas en español y catalán

    Directory of Open Access Journals (Sweden)

    José Luis Vicedo

    2009-12-01

    Full Text Available

    Este artículo presenta una aproximacíon a la clasificación automática de preguntas en español y catalán. El sistema de clasificación está basado en el algoritmo SVM y en el uso de diferentes funciones kernel, empleando únicamente características textuales superficiales que permiten la obtencíon de un sistema fácilmente adaptable a diferentes idiomas. Se ha realizado un estudio sobre el correcto a juste de parámetros de los kernels, la precisíon de los mismos, la definicíon de distintos vectores de características de aprendizaje y el rendimiento en función del idioma de trabajo. Adicionalmente, se ha experimentado con el algoritmo LIBLINEAR, aplicado aquí por vez primera a la tarea de clasificación de preguntas. Con este algoritmo, así como con los kernels definidos, se han obtenido valores de precisión por encima del 80 % para los dos idiomas tratados, superando a otros algoritmos tradicionales de clasificación. Para el entrenamiento y evaluación del sistema se ha desarrollado un corpus paralelo de 2.393 preguntas en inglés, español y catalán.

  18. Reflexiones en torno a la revista Quaderns del Institut Català d'Antropologia

    Directory of Open Access Journals (Sweden)

    de Quaderns, Consejo de Redacción

    2002-06-01

    Full Text Available The journal Quaderns (1st period, 1980-87; 2nd, since 1994 appeared as the organ of the Catalan Institute of Anthropology. Though dedicated since its first issue to Catalan traditional ethnology, Quaderns reveals an increasing interest in identities and frontiers, aimed at understanding societies from the interrelations affecting them and concerned with diversity in the Catalan, Iberian and European context as well as in that of Latin America and Northwestern Africa.

    La revista Quaderns (1.a etapa, 1980-87; 2.a desde 1994 nació como medio de expresión del Institut Català d'Antropologia. Aunque manteniendo las investigaciones sobre etnología tradicional catalana, esta revista muestra un creciente interés por el tema de las identidades y las fronteras, buscando la comprensión de las sociedades desde la interrelación y apostando por la diversidad, no sólo en el ámbito catalán, ibérico y europeo, sino también en América Latina y el Magreb.

  19. Producción de hidrógeno y materiales carbonosos avanzados mediante descomposición catalítica de gas natural

    Directory of Open Access Journals (Sweden)

    J.M. Palacios

    2009-03-01

    Full Text Available La Descomposición Catalítica del Gas Natural (DCGN en la que el carbono se captura como un producto sólido de alto valor comercial, es una alternativa muy interesante al reformado, especialmente en pequeñas instalaciones descentralizadas.

  20. Adiabatic Coupling Constant of Nitrobenzene- n-Alkane Critical Mixtures. Evidence from Ultrasonic Spectra and Thermodynamic Data

    Science.gov (United States)

    Mirzaev, Sirojiddin Z.; Kaatze, Udo

    2016-09-01

    Ultrasonic spectra of mixtures of nitrobenzene with n-alkanes, from n-hexane to n-nonane, are analyzed. They feature up to two Debye-type relaxation terms with discrete relaxation times and, near the critical point, an additional relaxation term due to the fluctuations in the local concentration. The latter can be well represented by the dynamic scaling theory. Its amplitude parameter reveals the adiabatic coupling constant of the mixtures of critical composition. The dependence of this thermodynamic parameter upon the length of the n-alkanes corresponds to that of the slope in the pressure dependence of the critical temperature and is thus taken another confirmation of the dynamic scaling model. The change in the variation of the coupling constant and of several other mixture parameters with alkane length probably reflects a structural change in the nitrobenzene- n-alkane mixtures when the number of carbon atoms per alkane exceeds eight.

  1. Photo catalytic degradation of nitrobenzene using nanocrystalline TiO{sub 2} photo catalyst doped with Zn ions

    Energy Technology Data Exchange (ETDEWEB)

    Reynoso S, E. A.; Perez S, S.; Reyes C, A. P.; Castro R, C. L.; Felix N, R. M.; Lin H, S. W. [Instituto Tecnologico de Tijuana, Centro de Graduados e Investigacion, Apdo. Postal 1166, 22000 Tijuana, Baja California (Mexico); Paraguay D, F. [Centro de Investigacion en Materiales Avanzados, Apdo. Postal 311109, Chihuahua (Mexico); Alonso N, G. [UNAM, Centro de Nanociencias y Nanotecnologia, Carretera Tijuana-Ensenada Km 107, Apdo. Postal 356, 22800 Ensenada, Baja California (Mexico)

    2013-07-01

    Photo catalysis is a method widely used in the degradation of organic pollutants of the environment. The development of new materials is very important to improve the photo catalytic properties and to find new applications for TiO{sub 2} as a photo catalyst. In this article we reported the synthesis of a photo catalyst based on TiO{sub 2} doped with Zn{sup 2+} ions highly efficient in the degradation of nitrobenzene. The results of photo catalytic activity experiments showed that the Zn{sup 2+} doped TiO{sub 2} is more active that un-doped TiO{sub 2} catalyst with an efficiency of 99% for the nitrobenzene degradation at 120 min with an apparent rate constant of 35 x 10{sup -3} min{sup -1}. For the characterization of photo catalyst X-ray diffraction, transmission electron microscopy and Raman spectroscopy were used. (Author)

  2. High performance of a cobalt–nitrogen complex for the reduction and reductive coupling of nitro compounds into amines and their derivatives

    Science.gov (United States)

    Zhou, Peng; Jiang, Liang; Wang, Fan; Deng, Kejian; Lv, Kangle; Zhang, Zehui

    2017-01-01

    Replacement of precious noble metal catalysts with low-cost, non-noble heterogeneous catalysts for chemoselective reduction and reductive coupling of nitro compounds holds tremendous promise for the clean synthesis of nitrogen-containing chemicals. We report a robust cobalt–nitrogen/carbon (Co–Nx/C-800-AT) catalyst for the reduction and reductive coupling of nitro compounds into amines and their derivates. The Co–Nx/C-800-AT catalyst was prepared by the pyrolysis of cobalt phthalocyanine–silica colloid composites and the subsequent removal of silica template and cobalt nanoparticles. The Co–Nx/C-800-AT catalyst showed extremely high activity, chemoselectivity, and stability toward the reduction of nitro compounds with H2, affording full conversion and >97% selectivity in water after 1.5 hours at 110°C and under a H2 pressure of 3.5 bar for all cases. The hydrogenation of nitrobenzene over the Co–Nx/C-800-AT catalyst can even be smoothly performed under very mild conditions (40°C and a H2 pressure of 1 bar) with an aniline yield of 98.7%. Moreover, the Co–Nx/C-800-AT catalyst has high activity toward the transfer hydrogenation of nitrobenzene into aniline and the reductive coupling of nitrobenzene into other derivates with high yields. These processes were carried out in an environmentally friendly manner without base and ligands. PMID:28232954

  3. Photocatalytic Degradation of Trifluralin, Clodinafop-Propargyl, and 1,2-Dichloro-4-Nitrobenzene As Determined by Gas Chromatography Coupled with Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Niyaz A. Mir

    2014-01-01

    Full Text Available Phototransformation is considered one of the most key factors affecting the fate of pesticides. Therefore, our study focused on photocatalytic degradation of three selected pesticide derivatives: trifluralin (1, clodinafop-propargyl (2, and 1,2-dichloro-4-nitrobenzene (3. The degradation was carried out in acetonitrile/water medium in the presence of titanium dioxide (TiO2 under continuous purging of atmospheric air. The course of degradation was followed by thin-layer chromatography and gas chromatography-mass spectrometry techniques. Electron ionization mass spectrometry was used to identify the degradation species. GC-MS analysis indicates the formation of several intermediate products which have been characterized on the basis of molecular ion, mass fragmentation pattern, and comparison with NIST library. The photocatalytic degradation of pesticides of different chemical structures manifested distinctly different degradation mechanism. The major routes for the degradation of pesticides were found to be (a dealkylation, dehalogenation, and decarboxylation, (b hydroxylation, (c oxidation of side chain, if present, (d isomerization and cyclization, (e cleavage of alkoxy bond, and (f reduction of triple bond to double bond and nitro group to amino.

  4. Modeling of nitrobenzene in the river with ice process in high-latitude regions

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    To deal with the accidental release of pollutants into frozen rivers, those rivers in high-latitude regions should be treated differently. Pollutants could be stored up in the ice and released when the ice melts in spring, perhaps resulting in secondary pollution in the river. A water quality model of nitrobenzene has been developed in this paper to assess the influence on river water quality due to the freezing process. The model is made up of three modules: thermodynamic module, hydrodynamic module and water quality module. The thermodynamic module considers the complex heat exchange processes between the water body and the atmosphere, the water body and the river bed, the water body and the ice cover, and so on. The growth of the ice cover is simulated in a simplified form whilst taking consideration of heat balance. The hydrodynamic model uses the Saint-Venant equations in non-constant flow and the influence of the ice cover is measured. The degradation, diffusion, absorption and desorption, and the influence of the freezing process are incorporated in the water quality module and the concept of Con- tinuously Stirred Tanked Reactors (CSTRs) model is applied in the model construction. The model has been applied to supporting the management of accidental pollution in the Songhua River. The model was calibrated and validated with monitored data. Regional sensitivity analysis based on a task-based Hornberger-Spear-Young (HSY) algorithm was carried out to examine the model structure and the re- sult showed that the model could describe the system very well. Then the conditioned model was ap- plied to predicting the concentration of nitrobenzene in the water when the ice melted in spring. The predictive result showed that the release of pollutants in the ice could lead to an increase in the con- centration of pollutants in the water, but the increase would be very small because there was only a small amount of pollutants stored in the ice. A secondary pollution

  5. Modeling of nitrobenzene in the river with ice process in high-latitude regions

    Institute of Scientific and Technical Information of China (English)

    SUN PengCheng; ZENG SiYu; CHEN JiNing

    2009-01-01

    To deal with the accidental release of pollutants into frozen rivers,those rivers in high-latitude regions should be treated differently.Pollutants could be stored up in the ice and released when the ice melts in spring,perhaps resulting in secondary pollution in the river.A water quality model of nitrobenzene has been developed in this paper to assess the influence on river water quality due to the freezing process.The model is made up of three modules:thermodynamic module,hydrodynamic module and water quality module.The thermodynamic module considers the complex heat exchange processes between the water body and the atmosphere,the water body and the river bed,the water body and the ice cover,and so on.The growth of the ice cover is simulated in a simplified form whilst taking consideration of heat balance.The hydrodynamic model uses the Saint-Venant equations in non-constant flow and the influence of the ice cover is measured.The degradation,diffusion,absorption and desorption,and the influence of the freezing process are incorporated in the water quality module and the concept of Continuously Stirred Tanked Reactors (CSTRs) model is applied in the model construction.The model has been applied to supporting the management of accidental pollution in the Songhua River.The model was calibrated and validated with monitored data.Regional sensitivity analysis based on a task-based Hornberger-Spear-Young (HSY) algorithm was carried out to examine the model structure and the result showed that the model could describe the system very well.Then the conditioned model was applied to predicting the concentration of nitrobenzene in the water when the ice melted in spring.The predictive result showed that the release of pollutants in the ice could lead to an increase in the concentration of pollutants in the water,but the increase would be very small because there was only a small amount of pollutants stored in the ice.A secondary pollution could therefore be avoided

  6. Tracking molecular structure deformation of nitrobenzene and its torsion-vibration coupling by intense pumping CARS

    Science.gov (United States)

    Wang, Chang; Wu, Hong-Lin; Song, Yun-Fei; He, Xing; Yang, Yan-Qiang; Tan, Duo-Wang

    2016-11-01

    The structural deformation induced by intense laser field of liquid nitrobenzene (NB) molecule, a typical molecule with restricting internal rotation, is tracked by time- and frequency-resolved coherent anti-Stokes. Raman spectroscopy (CARS) technique with an intense pump laser. The CARS spectra of liquid NB show that the NO2 torsional mode couples with the NO2 symmetric stretching mode, and the NB molecule undergoes ultrafast structural deformation with a relaxation time of 265 fs. The frequency of NO2 torsional mode in liquid NB (42 cm-1) at room temperature is found from the sum and difference combination bands involving the NO2 symmetric stretching mode and torsional mode in time- and frequency-resolved CARS spectra. Project supported by the National Natural Science Foundation of China (Grant Nos. 21173063 and 21203047), the Foundation of Heilongjiang Bayi Agricultural University, China (Grant No. XZR2014-16), NSAF (Grant No. U1330106), and the Special Research Project of National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics (Grant No. 2012-S-07).

  7. [Effect of inorganic ions on degradation of trace nitrobenzene in aqueous solution by catalytic ozonation].

    Science.gov (United States)

    Zhao, Lei; Ma, Jun; Sun, Zhi-zhong

    2006-05-01

    The experiment investigated the effects of general inorganic ions in natural source water on the three processes of ozonation alone, ceramic honeycomb and modified ceramic honeycomb-catalyzed ozonation for degradation of trace nitrobenzene in aqueous solution. The removal rate of ozonation alone and modified ceramic honeycomb-catalyzed ozonation increased by 5.0% and 8.6% with the increase of the concentration of calcium ion (0-4 mg x L(-1)), and that of ceramic honeycomb-catalyzed ozonation reached the climax at the concentration of calcium ion 0.5 mg x L(-1) under the same experimental condition. The degradation efficiency of ozonation alone, ceramic honeycomb and modified ceramic honeycomb-catalyzed ozonation enhanced by 10.9%, 11.6% and 9.6% with the increase of the concentration of manganese ion (0-4 mg x L(-1)), respectively, and decreased by 8.6%, 11.5% and 8.9% with the increase of the concentration of bicarbonate ion (0-200 mg x L(-1)). The concentration of nitrate and sulfate ion had no remarkable effect on ozonation alone, but the removal rate of other two processes decreased with the increase of the concentration of nitrate and sulfate ion.

  8. Fluorescence quenching of uric acid solubilized in bicontinuous microemulsion by nitrobenzene

    Directory of Open Access Journals (Sweden)

    Maurice O. Iwunze

    2013-02-01

    Full Text Available Abstract: Uric Acid is known to be practically insoluble in aqueous and alcoholic media. However, it exhibits a reasonable solubility in a Bicontinuous Microemulsion system – a 15-fold or more increase in solubility in this system compared to its solubility in water. The bicontinuous microemulsion is made up of three components –Dodecane-Surfactant-water. Uric acid solubilized in this system is quenched by nitrobenzene. The obtained fluorescence data do not obey the Stern-Volmer equation when plotted accordingly. Therefore, the modified Stern-Volmer equation was used to analyze the data. It was observed that only one third (1/3 of uric acid is accessible to quenching in this medium and the reaction is diffusion-limited. The Stern-Volmer quenching constant, KSV, was calculated to be 130 M-1 and the fluorescence lifetime, 0, the quantum yield,, and the bimolecular quenching rate constant, kq, were calculated as 10.6 nanoseconds, 0.06 and 1.231010 M-1s-1, respectively.

  9. [Power generation from glucose and nitrobenzene degradation using the microbial fuel cell].

    Science.gov (United States)

    Li, Jie; Liu, Guang-Li; Zhang, Ren-Duo; Luo, Yong; Zhang, Cui-Ping; Li, Ming-Chen; Quan, Xiang-Chun

    2010-11-01

    By constructing a dual-chamber microbial fuel cell (MFC), experiments were carried out using an initial glucose concentration of 1 000 mg/L with different nitrobenzene (NB) concentrations (0, 50, 150 and 250 mg/L) as the MFC's fuel. Results showed that with an external resistance of 1 000 omega, the initial glucose concentration of 1 000 mg/L and the initial NB concentrations of 0, 50, 150, 250 mg/L, the operation periods were 55.7, 51.6, 45.9 and 32.2 h, respectively, the maximum voltage outputs were 670, 597, 507, and 489 mV, the maximum volumetric power densities were 28.57, 20.42, 9.29, and 8.47 W/m3, and the electric charges were 65.10, 43.50, 35.48, and 30.32 C. The MFC could use the NB and glucose mixtures as fuel and generated stable electricity outputs. The degradation rates of NB in the MFC in all cases reached up to 100% and COD removals in the MFC were 87% - 98%. However, the electricity generation was negligible when using 250 mg/L NB as the sole fuel. Denaturing gradient gel electrophoresis (DGGE) profiles demonstrated that the presence of NB resulted in changes of the dominant bacterial species on the electrodes.

  10. Remediation of nitrobenzene contaminated soil by combining surfactant enhanced soil washing and effluent oxidation with persulfate.

    Directory of Open Access Journals (Sweden)

    Jingchun Yan

    Full Text Available The combination of surfactant enhanced soil washing and degradation of nitrobenzene (NB in effluent with persulfate was investigated to remediate NB contaminated soil. Aqueous solution of sodium dodecylbenzenesulfonate (SDBS, 24.0 mmol L-1 was used at a given mass ratio of solution to soil (20:1 to extract NB contaminated soil (47.3 mg kg-1, resulting in NB desorption removal efficient of 76.8%. The washing effluent was treated in Fe2+/persulfate and Fe2+/H2O2 systems successively. The degradation removal of NB was 97.9%, being much higher than that of SDBS (51.6% with addition of 40.0 mmol L-1 Fe2+ and 40.0 mmol L-1 persulfate after 15 min reaction. The preferential degradation was related to the lone pair electron of generated SO4•-, which preferably removes electrons from aromatic parts of NB over long alkyl chains of SDBS through hydrogen abstraction reactions. No preferential degradation was observed in •OH based oxidation because of its hydrogen abstraction or addition mechanism. The sustained SDBS could be reused for washing the contaminated soil. The combination of the effective surfactant-enhanced washing and the preferential degradation of NB with Fe2+/persulfate provide a useful option to remediate NB contaminated soil.

  11. Copper modified TiO2 catalysts: application to nitrobenzenes degradation

    Directory of Open Access Journals (Sweden)

    Chunyu Shui

    2016-01-01

    Full Text Available Copper doped TiO2 by the method of sol-gel preparation was conducted to stimulate the TiO2 visible light response and enhance the performance of photocatalytic degradation. By XRD, SEM and EDS analysis, molar ratio of 1.0%, 1.5%, 2.0% and 1.0% Cu doped TiO2 presented smaller grain sizes (20-50 nm than German P25 TiO2 (50-100 nm. Especially, 1.5% Cu doped TiO2 presented the highest and finest degree of crystallinity from XRD peak. Its reunion phenomenon was the weakest among all Cu doped TiO2. Combined with Cu doping structure, micro stress changes as well as the performance of the degradation of nitrobenzenes (NBs, the optimum mol ratio of Cu doped TiO2 was 1.5%. With 1.5% Cu doped TiO2 for 180 min UV light degradation of NBs, the removal efficiency was 60.02%, two times higher than that of Germany P25 TiO2. The reaction of NBs photocatalytic degradation by CuxTi(1-xO2 followed first order kinetics. Synthetically, SEM, ESD and performances of NBs degradation confirmed that the optimal formula of CuxTi(1-xO2 for degradation of NBs was Cu0.0183Ti0.9817O2.

  12. Co-TPP functionalized carbon nanotube composites for detection of nitrobenzene and chlorobenzene vapours

    Indian Academy of Sciences (India)

    Swasti Saxena; G S S SAINI; A L Verma

    2015-04-01

    We report preparation of nanocomposites by non-covalent functionalization of carbon nanotubes (CNTs) with metal-tetraphenylporphyrins (M-TPP). Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM) results suggest formation of nanosized clusters of Co-TPP around the CNTs surface. X-ray diffraction studies indicate electronic charge re-distribution and strong interactions among CNTs and Co-TPP on functionalization. The films of the hybrid CNT–M-TPP nanocomposite exhibit change in conductivity on exposure to some chemical vapours. In the present work, the films prepared from the cobalt-TPP functionalized CNTs hybrid composites have been investigated for the detection of chlorobenzene (CB) and nitrobenzene (NB) vapours at room temperature. The films show response time of few seconds on exposure to both the NB and CB vapours while the recovery time for NB is significantly different compared to CB. A distinct and highly reproducible response pattern in the relative changes in resistance, recovery and response times on exposure to the vapours of NB, CB and few other chemicals at room temperature has been exploited to differentiate CB and NB vapours from one another.

  13. Phototransformation of nitrobenzene in the Songhua River: kinetics and photoproduct analysis

    Institute of Scientific and Technical Information of China (English)

    WANG Aimin; HU Chun; QU Jiuhui; YANG Min; LIU Huijuan; RU Jia; QI Rong; SUN Jingfang

    2008-01-01

    Nitrobenzene (NB) pollution of the Songhua River caused by an explosion at a petrochemical plant in Jilin City, Jilin Province, China, attracted public concern over the fate of NB in the river. As one of the efforts to predict the fate of residual NB in the river, the kinetics and mechanism of phototransformation of NB in natural water from four sections of the Songhua River were investigated. It was found that photodegradation of NB in water proceeded via pseudo-first-order reaction kinetics under simulated solar irradiation conditions, and the rate constant (k) in the ultrapure water system was 0.0168 h-1, which was approximately half of those in the natural river water systems (0.323-0.402 h-1). The relatively short half-life of NB in natural river water systems (17.2-21.5 h) indicates that photodegradation might have played an important role in the loss of NB flux in the river. Nitrate concentration and alkalinity were the two main factors affecting the photochemical fate of NB, suggesting that decomposition of NB mediated by ·OH was predominant in water solution with high nitrate concentrations. Three isomeric nitrophenols, o-, m-, and p-nitrophenols, as well as phenol were detected as the main organic products in natural water under natural and simulated solar irradiations.

  14. An efficient Approach to Modify the Catalyst Activity for the Hydrogenation of Nitrobenzene

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The addition of a suitable amount of PPh3 to PdCI2 or PdC12(PhCN)2 in situ canconsiderably increase the catalytic activity in the hydrogenation of nitrobenzene, while the catalytic activities of PdCI2 (reduced)+PPh3, PdCI2(PPh3)2 and Pd(PPh3)4 are very poor. The poisoning of catalyst by mercury indicates that the catalytically active species are composed of Pd(0) colloidal particles. Transmission electron micrographs show that the size of nanometric Pd(0)particles of PdCI2 with PPh3 added in situ is smaller than that of PhC12(PPh3) or PdC12(reduced)+PPh3. A synergic effect of bimetallic catalysts such as PdCI2+nPPh3+NiC12 (n= 0.5, 1)and PdC12(PhCN)2+PPh3+FeCI3 gives rise to a further increase in the catalytic activity.

  15. Simulation and analysis of multi-stage centrifugal fractional extraction process of 4-nitrobenzene glycine enantiomers☆

    Institute of Scientific and Technical Information of China (English)

    Ping Wen; Kewen Tang; Jicheng Zhou; Panliang Zhang

    2015-01-01

    Based on the interfacial ligand exchange model and the law of conservation of mass, the multi-stage enantioselective liquid–liquid extraction model has been established to analyze and discuss on multi-stage centrifugal fractional extraction process of 4-nitrobenzene glycine (PGL) enantiomers. The influence of phase ratio, extractant concentra-tion, and PF6−concentration on the concentrations of enantiomers in the extract and raffinate was investigated by experiment and simulation. A good agreement between model and experiment was obtained. On this basis, the influence of many parameters such as location of stage, concentration levels, extractant excess, and number of stages on the symmetric separation performance was simulated. The optimal location of feed stage is the middle of fractional extraction equipment. The feed flow must satisfy a restricted relationship on flow ratios and the liquid throughout of centrifugal device. For desired purity specification, the required flow ratios decrease with extractant concentration and increase with PF6−concentration. When the number of stages is 18 stages at extractant excess of 1.0 or 14 stages at extractant excess of 2.0, the eeeq (equal enantiomeric excess) can reach to 99%.

  16. Ubicación óptima de platino en pellets catalíticos para la oxidación total de propileno

    Directory of Open Access Journals (Sweden)

    Javier Fontalvo Alzate

    2011-02-01

    Full Text Available En el presente artículo se muestra cual debe ser desde el punto de vista matemático, la ubicación óptima de platino dentro de un pellet catalítico para lograr que la actividad del pellet o el factor de efectividad sean máximos para la oxidación total de hidrocarburos, como el propileno. Esta ubicación de agente activo se lleva a cabo mediante una distribución Delta-Dirac. Adicionalmente se presenta el factor de efectividad como una función del módulo de Thiele, de la resistencia externa a los fenómenos de transporte y de la ubicación del platino dentro del pellet catalítico.

  17. Determinación de la acidez de sólidos por la prueba catalítica de la deshidratación del 1-butanol

    Directory of Open Access Journals (Sweden)

    Jaime Olmedo Pérez Oliveros

    2005-01-01

    Full Text Available En este trabajo se examina la deshidratación catalítica de 1-butanol para determinar la naturaleza de los centros ácidos de muestras de circonia sulfatada con o sin el dopaje de Ce, Sb o W así como, muestras de ZSM-5, Al-MCM-41 y permutita (aluminosilicato de naturaleza amorfa. La acidez de los diferentes catalizadores se ordenó dependiendo de la medida de la actividad catalítica y de la magnitud de las relaciones de abundancia relativa de los isómeros cis-buteno/trans-buteno (CB/TB, 1-buteno/trans-buteno (1B/TB e isobuteno/trans-buteno (IB/TB. Se encontró que la actividad aumenta a mayor contenido de sulfato en la circonia. Además, el catalizador Al-MCM-41 muestra un comportamiento similar a la mejor muestra de circonia sulfatada.

  18. Produção de massa de células permeabilizadas de Kluyveromyces lactis e atividade catalítica da bgalactosidase

    OpenAIRE

    Edimar A . F. Fontes; Passos,Flávia M.L.; Passos, Frederico J. V.; Paulo Rogério Fontes

    2008-01-01

    A produção de massa de célula permeabilizada de Kluyveromyces lactis contendo a enzimagalactosidase e sua atividade catalítica na hidrólise de lactose foi realizada. Para obtenção da massa de célula permeabilizada, células foram produzidas, crescendo em soro de leite UF estéril. Para promover a permeabilização da membrana, células foram tratadas com uma solução etanol 50% para facilitar o contato entre a enzima e o substrato no processo de hidrólise da lactose. A atividade catalítica da enzim...

  19. Solvent Extraction of Calcium into Nitrobenzene by Using an Anionic Ligand Based on Cobalt Bis(Dicarbollide) Anion with Covalently Bonded CMPO Function.

    Science.gov (United States)

    Makrlík, Emanuel; Selucký, Pavel; Vaňura, Petr

    2012-06-01

    From extraction experiments and γ-activity measurements, the exchange extraction constantcorresponding to the general equilibrium Ca2+(aq) + 2HL(nb) CaL2(nb) + 2H+(aq) taking place in the two-phase water-nitrobenzene (L- = anionic ligand based on cobalt bis(dicarbollide) anion with covalently bonded CMPO function; aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log Kex (Ca2+, 2HL) = 0.0 ± 0.1. Further, the stability constant of the electroneutral complex species CaL2 in water-saturated nitrobenzene was calculated for a temperature of 25 °C : log βnb (CaL2) = 11.0 ± 0.2.

  20. The Compositional Evolution of the Phyllosilicates in the Lateritic Profile of the Catalão I Ultramafic Alkaline-carbonatitic Complex (GO)

    OpenAIRE

    Rogério Guitarrari Azzone; Excelso Ruberti

    2010-01-01

    The compositional evolution of the phyllosilicates in the lateritic profile of the Catalão I ultramafic alkaline-carbonatiticcomplex (GO) is proposed in this work based on petrographic and X-ray diffraction analysis, as well as, chemical compositionobtained by WDS electron microprobe. The micaceous minerals found in unweathered rocks are classified as phlogopites(with different parageneses) and tetraferriphlogopites (metasomatic products). In the levels of altered rocks and isalteriticsaproli...

  1. Dental caries and dental fluorosis in 7-12-year-old schoolchildren in Catalão, Goiás, Brazil

    OpenAIRE

    Bardal, Priscila Ariede Petinuci; OLYMPIO, Kelly Polido Kaneshiro; Buzalaf, Marília Afonso Rabelo; BASTOS, José Roberto Magalhães

    2005-01-01

    INTRODUCTION: Over the last two decades, the prevalence of dental caries in children has decreased and the prevalence of dental fluorosis has increased. Knowledge on the epidemiologic conditions of a population is fundamental for the planning of health programs. OBJECTIVES: To determine the prevalence of dental caries and dental fluorosis among schoolchildren, in Catalão, Goiás, Brazil. METHODS: A random sample of 432 schoolchildren aged 7-12-years old was obtained. WHO (1997) criteria for de...

  2. Research on Adsorption of Nitrobenzene by Modified Oganic Bentonite%有机改性膨润土对硝基苯的吸附研究

    Institute of Scientific and Technical Information of China (English)

    金伟; 任建敏

    2012-01-01

    通过用十六烷基三甲基溴化铵(简称CTMAB)改性膨润土,制得CTMAB有机土,并研究其对水体中的硝基苯的吸附效果;结果表明:对于50mL浓度为10mg/L的硝基苯水溶液,CTMAB有机土投加量为1g时,在80min左右,达到吸附平衡,对硝基苯的最大去除效率达到62.4%;pH对CTMAB有机土吸附硝基苯影响不大,对于钠化土有很大影响;CTMAB有机土对硝基苯的吸附符合Langmuir、Freundlich等温吸附模型。%The removal effect of nitrobenzene in the aqueous solution is studied by using the oganic bentonite modified by CTMAB. The results show that the best removal efficiency of nitrobenzene was up to 62.4% ,while the modified organic bentonite addtion amount was 1 g/50 mL of 10 mg/L nitrobenzene solution, the adsorption was balanced when the adsorption time was 80 min and initial coneetration of wastewater was 10 mg/L. pH value little affects the adsorption of nitrobenzene by CTMAB- bentonite, the influence of pH on the adsorption of nitrobenzene by CTMAB organic bentonite is small but is big by Na - bentonite. Adosrption isotherms of nitrobenzene is in accordance with Freundlich and Langmuir isothermal adsorption model.

  3. Thermal desorption-gas chromatography for the determination of benzene, aniline, nitrobenzene and chlorobenzene in workplace air.

    Science.gov (United States)

    Patil, S F; Lonkar, S T

    1992-05-29

    Sampling on Tenax TA of different mesh sizes followed by thermal desorption and gas chromatography was evaluated as a simple method for the determination of benzene, aniline, nitrobenzene and chlorobenzene in the workplace air. An alternative sampling technique in place of pump sampling was developed. Quantitative recoveries were obtained in the mass range 0.04-10 micrograms. It was found that air humidity had no effect on recovery. The charged tubes can be stored at room temperature for 5 days with no change in recovery. The particle size of Tenax TA has no significant effect on adsorption and desorption.

  4. Nitrobenzene anti-parallel dimer formation in non-polar solvents

    Directory of Open Access Journals (Sweden)

    Toshiyuki Shikata

    2014-06-01

    Full Text Available We investigated the dielectric and depolarized Rayleigh scattering behaviors of nitrobenzene (NO2-Bz, which is a benzene mono-substituted with a planar molecular frame bearing the large electric dipole moment 4.0 D, in non-polar solvents solutions, such as tetrachloromethane and benzene, at up to 3 THz for the dielectric measurements and 8 THz for the scattering experiments at 20 °C. The dielectric relaxation strength of the system was substantially smaller than the proportionality to the concentration in a concentrated regime and showed a Kirkwood correlation factor markedly lower than unity; gK ∼ 0.65. This observation revealed that NO2-Bz has a tendency to form dimers, (NO2-Bz2, in anti-parallel configurations for the dipole moment with increasing concentration of the two solvents. Both the dielectric and scattering data exhibited fast and slow Debye-type relaxation modes with the characteristic time constants ∼7 and ∼50 ps in a concentrated regime (∼15 and ∼30 ps in a dilute regime, respectively. The fast mode was simply attributed to the rotational motion of the (monomeric NO2-Bz. However, the magnitude of the slow mode was proportional to the square of the concentration in the dilute regime; thus, the mode was assigned to the anti-parallel dimer, (NO2-Bz2, dissociation process, and the slow relaxation time was attributed to the anti-parallel dimer lifetime. The concentration dependencies of both the dielectric and scattering data show that the NO2-Bz molecular processes are controlled through a chemical equilibrium between monomers and anti-parallel dimers, 2NO2-Bz ↔ (NO2-Bz2, due to a strong dipole-dipole interaction between nitro groups.

  5. Linseed (Linum usitatissimum L. as a biocatalyst for reduction of nitroaromatic compounds

    Directory of Open Access Journals (Sweden)

    Leonardo C. Tavares

    2014-06-01

    Full Text Available The reduction of nitroaromatic compounds is an important transformation that be used in the synthesis of amines which are interesting intermediates of pharmaceuticals and other derivatives. Linseed, Linum usitatissimum L., were used to catalyze biotransformations of nitrobenzene, ortho-nitroacetophenone, meta- nitroacetophenone and para-nitroacetophenone. Ortho-aminoacetophenone, and para- aminoacetophenone were obtained with excellent chemoselectivity (92.1 to ≥99%.

  6. A Reduction-Based Sensor for Acrolein Conjugates with the Inexpensive Nitrobenzene as an Alternative to Monoclonal Antibody

    Science.gov (United States)

    Takamatsu, Masayuki; Fukase, Koichi; Oka, Ritsuko; Kitazume, Shinobu; Taniguchi, Naoyuki; Tanaka, Katsunori

    2016-01-01

    Acrolein, a highly toxic α, β–unsaturated aldehyde, has been a longstanding key biomarker associated with a range of disorders related to oxidative stresses. One of the most promising methods for detecting acrolein involves the use of antibodies that can recognize the acrolein–lysine conjugate, 3-formyl-3, 4-dehydropiperidines (FDP), within oxidatively stressed cells and tissues from various disease states. We have uncovered here that FDP could reduce nitroarenes in high yields at 100 °C in the presence of excess CaCl2 as a Lewis acid promoter. This unique transformation allowed for the development of a de novo method for detecting levels of FDPs generated from proteins in urine or blood serum samples. Thus we successfully converted a non-fluorescent and inexpensive 4-nitrophthalonitrile probe to the corresponding fluorescent aniline, thereby constituting the concept of fluorescent switching. Its sensitivity level (0.84 nmol/mL) is more than that of ELISA assays (3.13 nmol/mL) and is already equally reliable and reproducible at this early stage of development. More importantly, this method is cost effective and simple to operate, requiring only mixing of samples with a kit solution. Our method thus possesses potential as a future alternative to the more costly and operatively encumbered conventional antibody-based methods. PMID:27782170

  7. COMPARISON BETWEEN ANALYTICAL PYROLYSIS AND NITROBENZENE OXIDATION FOR DETERMINATION OF SYRINGYL/GUAIACYL RATIO IN Eucalyptus spp. LIGNIN

    Directory of Open Access Journals (Sweden)

    Cláudio F. Lima

    2008-08-01

    Full Text Available Pyrolysis-gas chromatography/mass spectrometry (Py-GC-MS was applied to measure the lignin syringyl/guaiacyl (S/G ratio in E. dunni, E. grandis, E. nitens, E. urograndis, and E. urophylla woods. A total of 41 compounds were identified, of which 11 were derived from carbo-hydrates and 30 from lignins. The S/G ratio was calculated on the basis of the areas of peaks recorded in the pyrograms and compared with the results obtained by alkaline nitrobenzene oxidation. The values of S/G found by pyrolysis were similar for all the species using the compounds guaiacol, 4-methylguaiacol, 4-vinylguaiacol, vanillin, 4-ethylsyringol, 4-vinylsyringol, homosyringaldehyde, acetosyringone, and syringylacetone, as lignin markers. The selected markers were efficient for the deter-mination of S/G ratio in eucalyptus wood by Py-GC-MS. The Py-GC-MS technique produced results that are comparable to the nitrobenzene oxidation method, with the advantage of requiring small wood samples and a short analysis time.

  8. Site-Specific Description of the Enhanced Recognition Between Electrogenerated Nitrobenzene Anions and Dihomooxacalix[4]arene Bidentate Ureas.

    Science.gov (United States)

    Martínez-González, Eduardo; Armendáriz-Vidales, Georgina; Ascenso, José R; Marcos, Paula M; Frontana, Carlos

    2015-05-01

    Electron transfer controlled hydrogen bonding was studied for a series of nitrobenzene derivative radical anions, working as large guest anions, and substituted ureas, including dihomooxacalix[4]arene bidentate urea derivatives, in order to estimate binding constants (Kb) for the hydrogen-bonding process. Results showed enhanced Kb values for the interaction with phenyl-substituted bidentate urea, which is significantly larger than for the remaining compounds, e.g., in the case of 4-methoxynitrobenzene a 28-fold larger Kb value was obtained for the urea bearing a phenyl (Kb ∼ 6888) vs tert-butyl (Kb ∼ 247) moieties. The respective nucleophilic and electrophilic characters of the participant anion radical and urea hosts were parametrized with global and local electrodonating (ω(-)) and electroaccepting (ω(+)) powers, derived from DFT calculations. ω(-) data were useful for describing trends in structure–activity relationships when comparing nitrobenzene radical anions. However, ω(+) for the host urea structures lead to unreliable explanations of the experimental data. For the latter case, local descriptors ωk(+)(r) were estimated for the atoms within the urea region in the hosts [∑kωk(+)(r)]. By compiling all the theoretical and experimental data, a Kb-predictive contour plot was built considering ω(-) for the studied anion radicals and ∑kωk(+)(r) which affords good estimations.

  9. New Materials for Oxygen Reduction Electrodes

    DEFF Research Database (Denmark)

    Johansson, Tobias Peter

    This thesis is concerned with the discovery, characterisation and testing of new catalysts for the oxygen reduction reaction (ORR). A theroretical screening study was performed, in close collaboration with the theory group at the Center for Atomicscale Materials Design (CAMD), searching for catal......This thesis is concerned with the discovery, characterisation and testing of new catalysts for the oxygen reduction reaction (ORR). A theroretical screening study was performed, in close collaboration with the theory group at the Center for Atomicscale Materials Design (CAMD), searching...... as the sputter cleaned Pt3Sc. The deposition of Y on a Pt(111) crystal was then investigated. It was found that when annealing the crystal above 800 K a Pt overlayer was formed on top of a PtxY structure. Low energy electron diffraction (LEED) was used to probe the ordering of the surface and the LEED patterns...

  10. Simulación del Regenerador de una Unidad de Desintegración Catalítica Fluidizada (FCC

    Directory of Open Access Journals (Sweden)

    Roberto Hernández Enríquez

    2004-01-01

    Full Text Available Se presentan los resultados de aplicación de un modelo para simular el estado estacionario del regenerador de catalizador en una unidad de desintegración catalítica fluidizada, incluyendo una descripción cinética detallada del comportamiento de la fase densa y de la fase diluida, tanto en combustión parcial como en combustión total. El desarrollo del modelo está basado en considerar que los gases en flujo pistón, a través de las dos fases, y el catalizador en el lecho denso se encuentran bien mezclados y son isotérmicos. Los balances de materia y energía quedan descritos por sistemas de ecuaciones diferenciales ordinarias, para la fase del gas en la cama densa y en la fase diluida, y por ecuaciones algebraicas no lineales para la fase del catalizador en la cama densa. Se ajustaron los parámetros cinéticos para representar un caso industrial y se estudió el comportamiento del modelo al modificar el flujo de aire alimentado.

  11. Cervantisme català i traducció: anàlisi d'adaptacions infantils i juvenils

    Directory of Open Access Journals (Sweden)

    Rosa Agost

    2013-07-01

    Full Text Available Al voltant de 2005, quart centenari de la publicació de la primera part del Quixot, hem constatat l’aparició de vint adaptacions i versions al català per a joves i infants d’aquesta obra cervantina. La dada resulta especialment significativa si tenim en compte que durant els tres segles anteriors únicament se’n van editar set. En aquest article oferirem una relació i una anàlisi descriptiva que integra text i imatge, de totes les reescriptures derivades de l’obra original adreçades al públic infantil i juvenil, amb referència especial a aquelles publicades entre 2004 i 2005. Així mateix, analitzarem les dades obtingudes de l’anàlisi des d’una perspectiva holística que ens permet descriure alguns factors del context comunicatiu, especialment determinats aspectes sociològics de les adaptacions, estudiar la importància de determinats elements paratextuals i sistematitzar algunes estratègies i tècniques de traducció que s’han fet servir.

  12. Protein engineering of toluene 4-monooxygenase of Pseudomonas mendocina KR1 for synthesizing 4-nitrocatechol from nitrobenzene.

    Science.gov (United States)

    Fishman, Ayelet; Tao, Ying; Bentley, William E; Wood, Thomas K

    2004-09-20

    After discovering that toluene 4-monooxygenase (T4MO) of Pseudomonas mendocina KR1 oxidizes nitrobenzene to 4-nitrocatechol, albeit at a very low rate, this reaction was improved using directed evolution and saturation mutagenesis. Screening 550 colonies from a random mutagenesis library generated by error-prone PCR of tmoAB using Escherichia coli TG1/pBS(Kan)T4MO on agar plates containing nitrobenzene led to the discovery of nitrocatechol-producing mutants. One mutant, NB1, contained six amino acid substitutions (TmoA Y22N, I84Y, S95T, I100S, S400C; TmoB D79N). It was believed that position I100 of the alpha subunit of the hydroxylase (TmoA) is the most significant for the change in substrate reactivity due to previous results in our lab with a similar enzyme, toluene ortho-monooxygenase of Burkholderia cepacia G4. Saturation mutagenesis at this position resulted in the generation of two more nitrocatechol mutants, I100A and I100S; the rate of 4-nitrocatechol formation by I100A was more than 16 times higher than that of wild-type T4MO at 200 microM nitrobenzene (0.13 +/- 0.01 vs. 0.008 +/- 0.001 nmol/min.mg protein). HPLC and mass spectrometry analysis revealed that variants NB1, I100A, and I100S produce 4-nitrocatechol via m-nitrophenol, while the wild-type produces primarily p-nitrophenol and negligible amounts of nitrocatechol. Relative to wild-type T4MO, whole cells expressing variant I100A convert nitrobenzene into m-nitrophenol with a Vmax of 0.61 +/- 0.037 vs. 0.16 +/- 0.071 nmol/min.mg protein and convert m-nitrophenol into nitrocatechol with a Vmax of 3.93 +/- 0.26 vs. 0.58 +/- 0.033 nmol/min.mg protein. Hence, the regiospecificity of nitrobenzene oxidation was changed by the random mutagenesis, and this led to a significant increase in 4-nitrocatechol production. The regiospecificity of toluene oxidation was also altered, and all of the mutants produced 20% m-cresol and 80% p-cresol, while the wild-type produces 96% p-cresol. Interestingly, the rate of

  13. Novel relationship between hydroxyl radical initiation and surface group of ceramic honeycomb supported metals for the catalytic ozonation of nitrobenzene in aqueous solution.

    Science.gov (United States)

    Zhao, Lei; Sun, Zhizhong; Ma, Jun

    2009-06-01

    Comparative experiments have been performed to investigate the degradation efficiency of nitrobenzene and the removal efficiency of TOC in aqueous solution bythe processes of ceramic honeycomb supported different metals (Fe, Ni, and Zn) catalytic ozonation, indicating that the modification with metals can enhance the activity of ceramic honeycomb for the catalytic ozonation of nitrobenzene, and the loading percentage of metal and the metallicity respectively presents a positive influence on the degradation of nitrobenzene. The degradation efficiency of nitrobenzene is determined by the initiation of hydroxyl radical (*OH) according to a good linear correlation in all the processes of modified ceramic honeycomb catalytic ozonation at the different loading percentages of metals. The modification of ceramic honeycomb with metals results in the conversion of the pH at the point of zero charge (pHpzc) and the evolution of surface groups. Divergence from the conventional phenomenon, the enhancement mechanism of ozone decomposition on the modified ceramic honeycomb with metals is proposed due to the basic attractive forces of electrostatic forces or/and hydrogen bonding. Consequently, a novel relationship between the initiation of *OH and the surface-OH2+ group on the modified catalyst is established based on the synergetic effect between homogeneous and heterogeneous reaction systems.

  14. Effects of hydraulic retention time (HRT) and sludge retention time (SRT) on the treatment of nitrobenzene in AMBR/CSTR reactor systems.

    Science.gov (United States)

    Kuscu, O S; Sponza, D T

    2007-03-01

    The effect of hydraulic retention time (HRT) and solid retention time (SRT) on the biodegradation of a synthetic wastewater containing nitrobenzene was investigated in a sequential anaerobic migrating blanket reactor (AMBR) and aerobic completely stirred tank reactor (CSTR) system. Reactor performance was evaluated at six different HRTs (1,1.5,2,2.5,3.5,5.19 and 10.38 days) and at six different SRTs (32,53,76,217,415 and 932 days). The influent COD and nitrobenzene concentration were kept constant at 3000 mg l(-1) and 60 mg l(-1), respectively, during continuous operation. The maximum COD removal efficiency was found to be 92% at a HRT of 10.38 days and a SRT of 932 days in AMBR reactor. However, nitrobenzene removal efficiencies were found to be 99.9% through all HRTs and SRTs in AMBR reactor. Most of the influent COD and nitrobenzene concentrations were removed in first compartment of AMBR. The total and methane gas production rates increased from 2760 ml day(-1) to 11760 ml day(-1) and from 1300 ml day(-1) to 3331 ml day(-1), respectively, as the HRT was decreased from 10.38 to 1 day in AMBR. However, methane percentage decreased from 47% to 28% with decreased HRTs and SRTs. The methanogens inhibition was observed at lower HRTs. pH values in the compartments and the effluent of AMBR was between optimum values. TVFA concentrations in effluent of AMBR were measured as zero until a HRT of 3.5 days. In the aerobic CSTR reactor, the COD removal efficiency decreased from 79% to 68% with decreased HRT from 6.79 to 0.67 days. It was found that the nitrobenzene transformed to aniline under anaerobic phase, and then the aniline mineralized in the oxidative stage, with efficiencies varying between 79% to 99.9%, in anaerobic/aerobic reactor system.

  15. El contacto de lenguas castellano-catalán a la luz de los epistolarios catalano-cubanos

    Directory of Open Access Journals (Sweden)

    Rafael Cala Carvajal

    2011-04-01

    Full Text Available Normal 0 21 false false false ES X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} En este trabajo nos proponemos estudiar el contacto de lenguas en la Cataluña decimonónica partiendo de un corpus epistolar generado por la emigración catalana a Cuba (s. XIX, en vista de que el carácter semiculto de los emisores propicia que afloren fenómenos lingüísticos relacionados con la situación de bilingüismo en Cataluña. Así pues, se pretende constatar la importancia del siglo XIX en el contacto de lenguas catalán-castellano, puesto que muchos de los fenómenos detectados en dicha centuria configurarán el habla de la comunidad bilingüe de Cataluña del siglo XX.

  16. Esterase-D and chromosome patterns in Central Amazon piranha (Serrasalmus rhombeus Linnaeus, 1766 from Lake Catalão

    Directory of Open Access Journals (Sweden)

    Aylton Saturnino Teixeira

    2006-01-01

    Full Text Available This study presents additional genetic data on piranha (Serrasalmus rhombeus Linnaeus, 1766 complex previously diagnosed due to the presence of distinct cytotypes 2n = 58 and 2n = 60. Three esterase-D enzyme loci (Est-D1, Est-D2 and Est-D3 were examined and complemented with chromosomal data from 66 piranha specimens collected from Lake Catalão. For all specimens the Est-D1 and Est-D2 loci were monomorphic. In contrast, the Est-D3 locus was polymorphic with genotypes and alleles being differentially distributed in the previously described cytotypes and served as the basis for detecting a new cytotype (2n = 60 B. In cytotype 2n = 58 the Est-D3 locus was also polymorphic and presented Mendelian allelic segregation with four genotypes (Est-D3(11, Est-D3(12, Est-D3(22 and Est-D3(33 out of six theoretically possible genotypes, presumably encoded by alleles Est-D3¹ (frequency = 0.237, EsT-D3² (0.710 and Est-D3³ (0.053. A Chi-squared (chi2 test for Hardy-Weinberg equilibrium was applied to the Est-D3 locus and revealed a genetic unbalance in cytotype 2n = 58, indicating the probable existence in the surveyed area of different stocks for that karyotypic structure. A silent null allele (Est-D3(0 with a high frequency (0.959 occurred exclusively in the 2n = 60 cytotype. On the other hand, the new cytotype 2n = 60 B described here for the first time was monomorphic for the presumably fixed Est-D3³ allele. The data as a whole should contribute to the better understanding the rhombeus complex taxonomic status definition in the Central Amazon.

  17. Producción de hidrógeno por reformado catalítico en fase acuosa de disoluciones de metanol. Catalizador de Platino.

    OpenAIRE

    Izquierdo Oraa, Oihane

    2015-01-01

    El objetivo que persigue la línea de investigación en la que se engloba este trabajo es la obtención de hidrógeno desde disoluciones acuosas de metanol (aproximadamente del 10% de metanol), considerando estos compuestos como una forma de almacenar hidrógeno y obtenerlo a baja temperatura “on-board” en un vehículo mediante el reformado en fase acuosa. El reto es conseguir un sistema catalítico de pequeño volumen y rápida respuesta a las demandas de hidrógeno con elevado rendimiento y calidad a...

  18. Los SIG como instrumento para el análisis de las migraciones: el ejemplo del éxodo catalán de 1936

    Directory of Open Access Journals (Sweden)

    Cécile Burel

    2012-06-01

    Full Text Available Born in 1962 with the Canadian Geographical Information System (CGIS, the GIS knew a spectacular development and broaden its applications, touching various disciplines that made its potential come out. Nonetheless, many functions have not been exploited yet. And it is precisely in domains other than the most usual, such as the quantitative geography, that we can appreciate the value of this tool, as this historical research El éxodo catalán de 1936 a través de los Pirineos. De la derrota a la victoria demonstrates.

  19. Remodelación de las dos sedes que conforman la actual biblioteca del Centro de Física Miguel A. Catalán (Madrid)

    OpenAIRE

    2007-01-01

    Las bibliotecas integradas en el Centro de Física “Miguel A. Catalán” [CFMAC]: Sección de Óptica y Estructura de la Materia [M-IO] y Sección de Matemáticas y Física Fundamental [M-IMAFF] pertenecientes a los Institutos de Óptica y Estructura de la Materia y Matemáticas y Física Fundamental, se encuentran en proceso de reestructuración, primero, físico y, en un período a medio plazo estructural.

  20. Producción de hidrógeno por reformado catalítico en fase acuosa de disoluciones de metanol. Catalizador de Platino.

    OpenAIRE

    Izquierdo Oraa, Oihane

    2015-01-01

    El objetivo que persigue la línea de investigación en la que se engloba este trabajo es la obtención de hidrógeno desde disoluciones acuosas de metanol (aproximadamente del 10% de metanol), considerando estos compuestos como una forma de almacenar hidrógeno y obtenerlo a baja temperatura “on-board” en un vehículo mediante el reformado en fase acuosa. El reto es conseguir un sistema catalítico de pequeño volumen y rápida respuesta a las demandas de hidrógeno con elevado rendimiento y calidad a...

  1. Electricity generation by two types of microbial fuel cells using nitrobenzene as the anodic or cathodic reactants.

    Science.gov (United States)

    Li, Jie; Liu, Guangli; Zhang, Renduo; Luo, Yong; Zhang, Cuiping; Li, Mingchen

    2010-06-01

    The effect of nitrobenzene (NB) on electricity generation and simultaneous biodegradation of NB were studied with two types of microbial fuel cells (MFCs): a ferricyanide-cathode MFC with NB as the anodic reactant and a NB-cathode MFC. Compared to controls without NB, the presence of NB in the anode of the first MFC decreased maximum voltage outputs, maximum power densities and Coulombic efficiencies. No electricity was generated from the first MFC using NB as the sole fuel; however, the second MFC using NB as the electron acceptor generated electricity successfully with a maximum voltage of 400mV. NB was degraded completely within 24h in both anode and cathode chambers. Denaturing gradient gel electrophoresis (DGGE) profiles demonstrated that the presence of NB caused changes in relative abundance of the dominant bacterial species and emergence of new bacteria on the anodes.

  2. Amperometric detection of heavy metal ions in ion pair chromatography at an array of water/nitrobenzene micro interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, S. [Martin-Luther-Univ. Halle-Wittenberg, Merseburg (Germany). Fachbereich Chemie; Wang, H. [Martin-Luther-Univ. Halle-Wittenberg, Merseburg (Germany). Fachbereich Chemie; Muraczewska, M. [Martin-Luther-Univ. Halle-Wittenberg, Merseburg (Germany). Fachbereich Chemie; Mueller, H. [Martin-Luther-Univ. Halle-Wittenberg, Merseburg (Germany). Fachbereich Chemie

    1996-10-01

    A novel amperometric detector for heavy metal ions has been developed and successfully applied for ion pair chromatography. The detector is based on the electrochemical transfer of the metal ions across an array of water/nitrobenzene micro interfaces. The ion transfer is facilitated by the neutral ionophores methylenebis(diphenylphosphineoxide) and methylenebis(di- phenylphosphinesulfide). More than eight metals are separated in less than 15 min on an RP18 column using octyl sulfonate as ion pair reagent. For the heavy metals, the limits of decision are 19(Pb{sup 2+}), 9(Zn{sup 2+}), 9l (Co{sup 2+}), 8(Cd{sup 2+}) and 1.6(Mn{sup 2+}) {mu}g/L. The applicability of the new method for water samples is demonstrated. (orig.). With 3 figs., 2 tabs.

  3. [Study on mechanism of ceramic honeycomb-catalytic ozonation for the decomposition of trace nitrobenzene in aqueous solution].

    Science.gov (United States)

    Zhao, Lei; Ma, Jun; Sun, Zhi-Zhong; Liu, Zheng-Qian; Yang, Yi-Xin; Lu, Wei

    2007-02-01

    The experiment investigated effects of the presence of hydroxyl radical inhibitor on degradation efficiency of trace nitrobenzene in aqueous solution in the processes of ozonation alone and ceramic honeycomb-catalyzed ozonation, including HCO3-, CO3(2-), HPO4(2-), H2PO4- and tert-butanol, and studied preliminarily on their mechanism. The results indicated that degradation rate of the two processes both increased firstly and decreased subsequently with the increase of the concentration of HCO3- (0 - 200 mg x L(-1)), and reached the climax at the concentration of bicarbonate ion 50 mg x L(-1) under the same experimental condition. The degradation rates of ozonation alone and ozonation/ ceramic honeycomb both declined by 16.57% and 27.52% with the increase of the concentration of CO3(2-) (0 - 20 mg x L(-1)), respectively, and decreased by 13.61% and 17.52% with the addition of the concentration of HPO4(2-) (0 - 12 mg x L(-1)), and reduced by 6.61% and 12.52% with the enhancement of the concentration of H2PO4- (0 - 120 mg x L(-1)), and dropped by 30.06% and 46.09% with the increasing of the concentration of tert-butanol (0 - 10 mg x L(-1)). The experimental results indicated that decomposition of nitrobenzene in both processes all followed the mechanism of oxidization by OH free radical, and tert-butanol is a more suitable indicator for the radical type reaction. The removal rate of ozonation alone rose with the increase of the concentration of pH (3.02 - 10.96), but that of ozonation/ceramic honeycomb process reached the maximum at pH = 9.23.

  4. Contribution to the thermodynamics of sc3+, y3+, la3+ and trivalent lanthanide cations in the two-phase water-nitrobenzene extraction system.

    Science.gov (United States)

    Makrlík, Emanuel; Vaňura, Petr

    2011-06-01

    From the exchange extraction constants corresponding to the general equilibrium M3+(aq) + 3H+(nb) M3+(nb) + 3H+(aq) occurring in the two-phase water-nitrobenzene system (M3+ = Sc3+, Y3+, La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+, Lu3+; aq = aqueous phase, nb = nitrobenzene phase), the individual extraction constants of 16 trivalent metal cations were calculated. It was found that these individual extraction constants in the mentioned two-phase system increase in the following cation order: Sc3+ < Yb3+< Ho3+ < Er3+ < Tm3+, Lu3+ < Y3+, Dy3+ < Tb3+ < Gd3+ < Eu3+ < Sm3+ < Nd3+ < Pr3+ < La3+, Ce3+.

  5. An efficient hydrogenation catalyst in sulfuric acid for the conversion of nitrobenzene to p-aminophenol: N-doped carbon with encapsulated molybdenum carbide.

    Science.gov (United States)

    Wang, Tao; Dong, Zhen; Cai, Weimeng; Wang, Yongzheng; Fu, Teng; Zhao, Bin; Peng, Luming; Ding, Weiping; Chen, Yi

    2016-08-23

    The transfer of catalytic function from molybdenum carbide to N-doped carbon has been tested by encapsulating molybdenum carbide with N-doped carbon using a one-pot preparation process. The outer layer of N-doped carbon, inert itself, exhibits high activity and excellent selectivity with molybdenum carbide as the catalyst for the hydrogenation of nitrobenzene to p-aminophenol in sulfuric acid.

  6. Highly Selective Bifunctional Luminescent Sensor toward Nitrobenzene and Cu(2+) Ion Based on Microporous Metal-Organic Frameworks: Synthesis, Structures, and Properties.

    Science.gov (United States)

    Yang, Lirong; Lian, Chen; Li, Xuefei; Han, Yuyang; Yang, Lele; Cai, Ting; Shao, Caiyun

    2017-05-24

    Two metal-organic frameworks (MOFs), namely, [Ni(DTP)(H2O)]n (I) and [Cd2(DTP)2(bibp)1.5]n (II) (H2DPT = 4'-(4-(3,5-dicarboxylphenoxy) phenyl)-4,2':6',4″-terpyridine; bibp = 1,3-di(1H-imidazol-1-yl)propane), that present structural diversity were solvothermally prepared. Single-crystal X-ray diffraction analysis indicates that they consist of {NiN2O4} building units (for I) and {CdO4N2} and {CdO3N3} building units (for II), which are further linked by multicarboxylate H2DPT to construct microporous three-dimensional frameworks. The remarkable character of these frameworks is that coordination polymer II demonstrates highly selective and sensitive bifunctional luminescent sensor toward nitrobenzene and Cu(2+) ion. The fluorescence quenching mechanism of II caused by nitrobenzene is ascribed to electron transfer from electron-rich (II) to electron-deficient nitrobenzene. The result was also evidenced by the density functional theory. Furthermore, anti-ferromagnetic as well as electrochemical characters of Ni-MOF (I) were also investigated in this paper.

  7. Syntheses, structures and magnetic properties of four coordination polymers based on nitrobenzene dicarboxylate and various N-donor coligands

    Energy Technology Data Exchange (ETDEWEB)

    Li, Gui-Lian; Yin, Wei-Dong; Liu, Guang-Zhen; Ma, Lu-Fang [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022, Henan (China); Wang, Li-Ya, E-mail: gzliuly@126.com [College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022, Henan (China); College of Chemistry and Pharmacy Engineering, Nanyang Normal University, Nanyang 473061, Henan (China)

    2014-12-15

    Four new coordination polymers ([Ni(4-Nbdc)(bpa)(H{sub 2}O)]){sub n} (1), ([Co(4-Nbdc)(bpp) (H{sub 2}O)]){sub n} (2), ([Ni(4-Nbdc)(bpp)(H{sub 2}O)]·H{sub 2}O){sub n} (3), and ([Mn{sub 2}(3-Nbdc){sub 2}(bib){sub 3}]·2H{sub 2}O){sub n} (4) (4-Nbdc=4-nitrobenzene-1,2-dicarboxylate, 3-Nbdc=3-nitrobenzene-1,2-dicarboxylate, bpa=1,2-bi(4-pyridyl)ethane, bpp=1,3-bis(4-pyridyl)propane, and bib=1,4-bis(1-imidazoly)benzene), were synthesized by hydrothermal reactions, and characterized by single-crystal X-ray diffractions, elemental analysis, FT-IR, PXRD, TGA and magnetic analysis. Complexes 1 and 2 display quasi-trapezoidal chain and brick-wall layer, and both of them contain metal–carboxylate binuclear units. Complexes 3 and 4 exhibit three-dimensional frameworks with the (6{sup 6}) dia topology and (4{sup 4}.6{sup 10}.8)(4{sup 4}.6{sup 2}) fsc topology, and both of them contain metal–carboxylate chains. The carboxyl groups with syn-anti coordination mode mediate effectively the weak ferromagnetic coupling interaction within Ni(II)–carboxylate binuclear in 1 (J=1.27 cm{sup −1}) and Ni(II)–carboxylate chain in 3 (J=1.44 cm{sup −1}), respectively, and the carboxyl groups with anti-anti coordination mode leads to the classic antiferromagnetic coupling interaction within Mn(II)–carboxylate chain in 4 (J=−0.77 cm{sup −1}). - Highlights: • Four novel coordination polymers were hydrothermally synthesized. • 1 is 1D quasi-trapezoidal chain and 2 is brick-wall layer both with dinuclear units. • 3 and 4 show 3D frameworks both with 1D metal–carboxylate chains. • 1 and 3 exhibit ferromagnetic coupling, while 4 shows antiferromagnetic coupling.

  8. Efecto catalítico de metales sobre la estabilidad térmica de aceites de oliva

    Directory of Open Access Journals (Sweden)

    Molero Meneses, M.

    2001-12-01

    Full Text Available The catalytic effect at homogenous phase of several metals on the thermal stability of olive oils of different characteristics has been studied. Samples were prepared by dissolution of suitable amounts of organo-metallic compounds in the oils, to obtain concentrations of metal between 0–30 ppm. The compounds organo-metallic were: ferrocene (Fe-II, dibutyltin diacetate (Sn-II, copper acetylacetonate (Cu-II and lead acetate (Pb-IV. The study was carried out by applying thermal analysis techniques: thermogravimetry (TG and derivative thermogravimetry (DTG. The obtained results show that the degradation rate of the oil is always higher in the presence of metals and its value is as greater as higher is concentrations. On the other hand, the kinetic parameters of the thermodegradation reaction of the oil, activation energy a n d f requency factor, w ere deter mined from thermogravimetric data. The obtained values for both parameters confirm the negative influence of the tested metals on the oil thermal stability. This effect is more evident for lead, followed of iron and tin and finally copper. Likewise, the results of thermal analysis allow to define the order of thermal stability of oils of different origins and refined grades.Se estudia el efecto catalítico en fase homogénea de diversos metales sobre la estabilidad térmica de aceites de oliva de distintas características. Las muestras a analizar se prepararon disolviendo en los aceites las cantidades adecuadas de los metales en forma de compuestos organometálicos, en el intervalo de concentraciones comprendido entre 0-30 ppm. Dichos compuestos fueron: ferroceno (Fe-II, acetilacetonato de cobre (Cu-II, acetato de plomo (Pb-IV y diacetato de dibutil estaño (Sn-II. El estudio se llevó a cabo mediante las técnicas de análisis térmico, termogravimetría (TG y termogravimetría derivada (TGD. Los resultados obtenidos muestran que, en todos los casos, la velocidad de degradación del aceite

  9. Análisis comparativo de las traducciones al castellano y al catalán de la novela 'The Slow Regard of Silent Things'

    OpenAIRE

    Toro Atzori, Elisa

    2015-01-01

    Anàlisi comparatiu de les traduccions al castellà i al català d'alguns elements especialment importants a la novel·la The Slow regard of Silent Things, de Patrick Rotfuss, un spin off de la trilogia The Kingkiller Chronicle, que té lloc a un món on les paraules, i sobretot els noms, tenen una importància molt gran. Anàlisi en conjunt de la versió original i les traduccions de cada element, reconstrucció del procés de traducció i cerca d'un mètode global i un possible paral·lelisme entre ambdu...

  10. The preparation and chemical reaction kinetics of tungsten bronze thin films and nitrobenzene with and without a catalyst

    Science.gov (United States)

    Materer, Nicholas F.; Apblett, Allen; Kadossov, Evgueni B.; Khan, Kashif Rashid; Casper, Walter; Hays, Kevin; Shams, Eman F.

    2016-06-01

    Microcrystalline tungsten bronze thin films were prepared using wet chemical techniques to reduce a tungsten oxide thin film that was prepared by thermal oxidation of a sputter deposited tungsten metal film on a quartz substrate. The crystallinity of these films was determined by X-ray diffraction and the surface was characterized by X-ray and Ultra-Violet Photoelectron spectroscopy. The total amount of hydrogen incorporated in the film was monitored using absorbance spectroscopy at 900 nm. The oxidation kinetics of the film and the hydrogenation of nitrobenzene in hexane were measured as a function of film thickness. A satisfactory fit of the resulting kinetics was obtained using a model that involves two simultaneous processes. The first one is the proton diffusion from the bulk of the film to the surface, and the second is a reaction of the surface protons with the oxidants. Finally, the dependence of the reaction rates on the presence of catalytic amounts of first row transition metals on the surface of the film was explored.

  11. Degradation kinetics and mechanism of trace nitrobenzene by granular activated carbon enhanced microwave/hydrogen peroxide system.

    Science.gov (United States)

    Tan, Dina; Zeng, Honghu; Liu, Jie; Yu, Xiaozhang; Liang, Yanpeng; Lu, Lanjing

    2013-07-01

    The kinetics of the degradation of trace nitrobenzene (NB) by a granular activated carbon (GAC) enhanced microwave (MW)/hydrogen peroxide (H202) system was studied. Effects of pH, NB initial concentration and tert-butyl alcohol on the removal efficiency were examined. It was found that the reaction rate fits well to first-order reaction kinetics in the MW/GAC/H202 process. Moreover, GAC greatly enhanced the degradation rate of NB in water. Under a given condition (MW power 300 W, H202 dosage 10 mg/L, pH 6.85 and temperature (60 +/- 5)degrees C), the degradation rate of NB was 0.05214 min-1when 4 g/L GAC was added. In general, alkaline pH was better for NB degradation; however, the optimum pH was 8.0 in the tested pH value range of 4.0-12.0. At H202 dosage of 10 mg/L and GAC dosage of 4 g/L, the removal of NB was decreased with increasing initial concentrations of NB, indicating that a low initial concentration was beneficial for the degradation of NB. These results indicated that the MW/GAC/H202 process was effective for trace NB degradation in water. Gas chromatography-mass spectrometry analysis indicated that a hydroxyl radical addition reaction and dehydrogenation reaction enhanced NB degradation.

  12. Coupling of bio-PRB and enclosed in-well aeration system for remediation of nitrobenzene and aniline in groundwater.

    Science.gov (United States)

    Liu, Na; Ding, Feng; Wang, Liu; Liu, Peng; Yu, Xiaolong; Ye, Kang

    2016-05-01

    A laboratory-scale bio-permeable reactive barrier (bio-PRB) was constructed and combined with enclosed in-well aeration system to treat nitrobenzene (NB) and aniline (AN) in groundwater. Batch-style experiments were first conducted to evaluate the effectiveness of NB and AN degradation, using suspension (free cells) of degrading consortium and immobilized consortium by a mixture of perlite and peat. The NB and AN were completely degraded in 4 mg L(-1) when the aeration system was applied into the bio-PRB system. The NB and AN were effectively removed when the aeration system was functional in the bio-PRB. The removal efficiency decreased when the aeration system malfunctioned for 20 days, thus indicating that DO was an important factor for the degradation of NB and AN. The regain of NB and AN removal after the malfunction indicates the robustness of degradation consortium. No original organics and new formed by-products were observed in the effluent. The results indicate that NB and AN in groundwater can be completely mineralized in a bio-PRB equipped with enclosed in-well aeration system and filled with perlite and peat attached with degrading consortium.

  13. Oxidation of nitrobenzene by ozone in the presence of faujasite zeolite in a continuous flow gas-liquid-solid reactor.

    Science.gov (United States)

    Reungoat, J; Pic, J S; Manéro, M H; Debellefontaine, H

    2010-01-01

    This work investigates the oxidation of nitrobenzene (NB) by ozone in the presence of faujasite zeolite. Experiments were carried out in a gas-liquid-solid reactor were ozone transfer and NB oxidation took place at the same time. Three configurations of the reactor were compared: empty, filled with inert glass beads and filled with faujasite pellets. First, ozone transfer coefficient (k(L)a) and decomposition rate constant (k(C)) were determined for each configuration. In presence of solid, k(L)a was 2.0 to 2.6 times higher and k(C) was 5.0 to 6.4 times higher compared to the empty reactor. Then, the various configurations were evaluated in terms of NB removal and chemical oxygen demand (COD) decrease. The faujasite reactor showed higher removal of NB and decrease of COD compared to other configurations under the same conditions suggesting that the faujasite increases the oxidation rate of NB. Oxidation of NB in presence of faujasite also proved to be limited by the transfer of ozone from the gas to the liquid phase.

  14. Ultrasonic assisted-Fenton-like degradation of nitrobenzene at neutral pH using nanosized oxides of Fe and Cu.

    Science.gov (United States)

    ElShafei, Gamal M S; Yehia, F Z; Dimitry, O I H; Badawi, A M; Eshaq, Gh

    2014-07-01

    Ultrasonic-assisted heterogeneous Fenton reaction was used for degradation of nitrobenzene (NB) at neutral pH conditions. Nano-sized oxides of α-Fe2O3 and CuO were prepared, characterized and tested in degradation of NB (10 mg L(-1)) under sonication of 20 kHz at 25 °C. Complete degradation of NB was effected at pH 7 in presence of 10 mM H2O2 after 10 min of sonication in presence of α-Fe2O3 (1.0 g L(-1)), (k=0.58 min(-1)) and after 25 min in case of CuO (k=0.126 min(-1)). α-Fe2O3 showed also effective degradation under the conditions of 0.1 g L(-1) oxide and 5.0 mM of H2O2, even though with a lower rate constant (0.346 min(-1)). Sonication plays a major role in enhancing the production of hydroxyl radicals in presence of solid oxides. Hydroxyl radicals-degradation pathway is suggested and adopted to explain the differences noted in rate constants recorded on using different oxides. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Rapid removal of nitrobenzene in a three-phase ozone loaded system with gas-liquid-liquid

    Science.gov (United States)

    Li, Shiyin; Zhu, Jiangpeng; Wang, Guoxiang; Ni, Lixiao; Zhang, Yong; Green, Christopher T.

    2015-01-01

    This study explores the removal rate of nitrobenzene (NB) using a new gas-liquid-liquid (G-L-L) three-phase ozone loaded system consisting of a gaseous ozone, an aqueous solvent phase, and a fluorinated solvent phase (perfluorodecalin, or FDC). The removal rate of NB was quantified in relation to six factors including 1) initial pH, 2) initial NB dosage, 3) gaseous ozone dosage, 4) free radical scavenger, 5) FDC pre-aerated gaseous ozone, and 6) reuse of FDC. The NB removal rate is positively affected by the first three factors. Compared with the conventional gas-liquid (water) (G-L) two-phase ozonation system, the free radical scavenger (tertiary butyl alcohol) has much less influence on the removal rate of NB in the G-L-L system. The FDC loaded ozone acts as an ozone reservoir and serves as the main reactive phase in the G-L-L three-phase system. The reuse of FDC has little influence on the removal rate of NB. These experimental results suggest that the oxidation efficiency of ozonation in the G-L-L three-phase system is better than that in the conventional G-L two-phase system.

  16. The Compositional Evolution of the Phyllosilicates in the Lateritic Profile of the Catalão I Ultramafic Alkaline-carbonatitic Complex (GO

    Directory of Open Access Journals (Sweden)

    Rogério Guitarrari Azzone

    2010-07-01

    Full Text Available The compositional evolution of the phyllosilicates in the lateritic profile of the Catalão I ultramafic alkaline-carbonatiticcomplex (GO is proposed in this work based on petrographic and X-ray diffraction analysis, as well as, chemical compositionobtained by WDS electron microprobe. The micaceous minerals found in unweathered rocks are classified as phlogopites(with different parageneses and tetraferriphlogopites (metasomatic products. In the levels of altered rocks and isalteriticsaprolite, the phyllosilicates derived from micas are vermiculite and regular interstratified phlogopite-vermiculite (whichformation and characteristics are similar to hydrobiotite, characterizing a main vermiculitization process in this profile.Subordinately, in the upper portions and punctual areas of isalteritic saprolite, the alteration of the vermiculitized phlogopitegenerates smectitic products, which are characterized mainly by the occurrence of expansible regular interstratified mineraland even smectite. Kaolinite occurs on the top of the isalteritic saprolite and on the alloteritic level. The evolution sequenceof the phyllosilicates in the weathering profile of the Catalão I complex presents the following formation order: phlogopite,interstratified phlogopite-vermiculite, vermiculite, smectitic products (expansible interstratified minerals of local occurrence, smectite and kaolinite, of which, the last two are probably associated to supergene processes. This sequence is compatible with the most recent theories for the formation of clay minerals in soils. The main differences between the phlogopites and their products ofvermiculitic alteration are related to a significant decrease of K+ and oxidation of Fe2+, characteristic changes of the vermiculitizationprocess. In the specific case of vermiculites, the interlayer site is filled mainly by Mg2+. In addition to that, the presence of interstratified minerals (intermediate alteration products is a key

  17. U-Pb ages, geochemistry, C-O-Nd-Sr-Hf isotopes and petrogenesis of the Catalão II carbonatitic complex (Alto Paranaíba Igneous Province, Brazil): implications for regional-scale heterogeneities in the Brazilian carbonatite associations

    Science.gov (United States)

    Guarino, Vincenza; Wu, Fu-Yuan; Melluso, Leone; de Barros Gomes, Celso; Tassinari, Colombo Celso Gaeta; Ruberti, Excelso; Brilli, Mauro

    2017-09-01

    The Catalão II carbonatitic complex is part of the Alto Paranaíba Igneous Province (APIP), central Brazil, close to the Catalão I complex. Drill-hole sampling and detailed mineralogical and geochemical study point out the existence of ultramafic lamprophyres (phlogopite-picrites), calciocarbonatites, ferrocarbonatites, magnetitites, apatitites, phlogopitites and fenites, most of them of cumulitic origin. U-Pb data have constrained the age of Catalão I carbonatitic complex between 78 ± 1 and 81 ± 4 Ma. The initial strontium, neodymium and hafnium isotopic data of Catalão II (87Sr/86Sri = 0.70503-0.70599; ɛNdi = -6.8 to -4.7; 176Hf/177Hf = 0.28248-0.28249; ɛHfi = -10.33 to -10.8) are similar to the isotopic composition of the Catalão I complex and fall within the field of APIP kimberlites, kamafugites and phlogopite-picrites, indicating the provenance from an old lithospheric mantle source. Carbon isotopic data for Catalão II carbonatites (δ13C = -6.35 to -5.68 ‰) confirm the mantle origin of the carbon for these rocks. The origin of Catalão II cumulitic rocks is thought to be caused by differential settling of the heavy phases (magnetite, apatite, pyrochlore and sulphides) in a magma chamber repeatedly filled by carbonatitic/ferrocarbonatitic liquids ( s.l.). The Sr-Nd isotopic composition of the Catalão II rocks matches those of APIP rocks and is markedly different from the isotopic features of alkaline-carbonatitic complexes in the southernmost Brazil. The differences are also observed in the lithologies and the magmatic affinity of the igneous rocks found in the two areas, thus demonstrating the existence of regional-scale heterogeneity in the mantle sources underneath the Brazilian platform.

  18. Solvent Extraction of Some Divalent Metal Cations into Nitrobenzene by Using a Synergistic Mixture of Strontium Dicarbollylcobaltate and p-tert-Butylcalix[4]arene-tetrakis (N,N-Diethylacetamide).

    Science.gov (United States)

    Makrlík, Emanuel; Budka, Jan; Vaňura, Petr; Selucký, Pavel

    2012-12-01

    From extraction experiments and g-activity measurements, the exchange extraction constants corresponding to the general equilibrium M2+(aq) + 1•Sr2+(nb) 1•M2+(nb) + Sr2+(aq) taking place in the two-phase water-nitrobenzene system (M2+ = Ca2+, Ba2+, Cu2+, Zn2+, Cd2+, Pb2+, UO22+, Mn2+, Co2+, Ni2+; 1 = p-tert-butylcalix[4]arene-tetrakis(N,N-diethylacetamide); aq = aqueous phase, nb = nitrobenzene phase) were determined. Further, the stability constants of the 1•M2+ complexes in water-saturated nitrobenzene were calculated; they were found to increase in the series of Cu2+ < Ba2+ < Zn2+ < Ni2+ < UO22+ < Co2+ < Mn2+ < Cd2+ < Ca2+ < Pb2+.

  19. Capa catalítica para la activación de oxígeno sobre electrolitos sólidos iónicos a alta temperatura

    OpenAIRE

    Serra Alfaro, José Manuel; Vert Belenguer, Vicente Bernard; Escolástico Rozalén, Sonia

    2008-01-01

    Capa catalítica para la activación de oxígeno sobre electrolitos sólidos iónicos a alta temperatura. La presente invención se refiere a una capa porosa catalítica para la activación de oxígeno que puede ser utilizada en pilas de combustible de óxidos sólidos (SOFC) y en membranas cerámicas densas de separación de oxígeno de alta temperatura. Esta capa porosa está formada principalmente por un material conductor mixto de electrones y del ión oxígeno y posee una estructu...

  20. Eliminación catalítica de compuestos orgánicos volátiles presentes en pequeñas y medianas empresas mediante la adaptación de extractores comerciales de aire

    OpenAIRE

    Colman Lerner, Jorge Esteban; Peluso, Miguel Ángel; Porta, Atilio Andrés; Horacio J. Thomas; Sambeth, Jorge

    2012-01-01

    El trabajo se enmarca en la modificación de un extractor de aire comercial, al cual se le colocó en la chimenea de venteo un sistema catalítico, evaluándose la eliminación de Compuestos Orgánicos Volátiles (COVs) tales como metiletilcetona, cloroformo, tolueno, m-xileno, o-xileno y p-xileno. Se estudió la actividad catalítica de sistemas en base a platino, óxido de manganeso, y óxido de manganeso dopado con Pt, todos ellos soportados sobre monolitos de bentonita. La elección de los COVs a eli...

  1. Síntesis y caracterización de carbones mesoporosos para su uso como soporte catalítico en reacciones en fase líquida para la obtención de bio-propilenglicol

    OpenAIRE

    Gatti, Martín; Santori, Gerardo Fabián; Pompeo, Francisco; Nora N. Nichio

    2015-01-01

    Se estudió la síntesis y caracterización de un material mesoporoso de base carbonosa (SiO2-C) el cual fue sometido a severas condiciones hidrotérmicas y posteriomente se lo evaluó como soporte catalítico. El material (SiO2-C) fue obtenido a partir de la cogelificación de TEOS y una resina fenólica. Entre sus características presenta una estrecha distribución de tamaño de poro en la región meso-porosa, un PZC = 7 y neutralidad superficial. Para evaluarlo catalíticamente se prepararon catalizad...

  2. Density, Viscosity, Sound Speed, and Thermoacoustical Parameters of Benzaldehyde with Chlorobenzene or Nitrobenzene at 303.15 K, 308.15 K, and 313.15 K

    Science.gov (United States)

    Lavanya, T. G.; Saravanakumar, K.; Baskaran, R.; Kubendran, T. R.

    2013-07-01

    The values of the density, viscosity, and speed of sound for binary liquid mixtures of benzaldehyde with chlorobenzene or nitrobenzene have been measured over the entire range of composition at (303.15, 308.15, and 313.15) K. These values have been used to calculate the excess molar volume (), and excess free volume (). McAllister's three-body interaction model is used for correlating the kinematic viscosity of binary mixtures. The thermophysical properties (density, viscosity, and ultrasonic velocity) under study were fit to the Jouyban-Acree model.

  3. Sparing the ortho-position in nucleophilic aromatic substitution-specific displacement of the 4-SePh group in 2,4-bis(phenylseleno)nitrobenzene

    DEFF Research Database (Denmark)

    Stuhr-Hansen, Nicolai; Götze, Thorstein Finn; Henriksen, Lars;

    2009-01-01

    -(phenylseleno)nitrobenzene 3 was observed. This product remained unreactive toward an excess of sodium methoxide, thus preventing the for-mation of 2,4-dimethoxynitrobenzene 6. The nature of the reactants and of the intermediate Meisenheimer complexes was examined by synthetic investigations, x......-ray crystallography, and DFT calculations. We found that the observed selectivity can be understood in terms of traditional resonance considerations. (C) 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:101-108, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20519...

  4. Unexpected Substitution of Alkyloxy-nitrobenzene%邻硝基酚醚上的异常取代反应

    Institute of Scientific and Technical Information of China (English)

    张裴; 童元峰; 王冬梅; 吴松

    2011-01-01

    以2-(2-硝基苯氧基)-1-溴乙烷或3-(2-硝基苯氧基)-1-溴丙烷为原料分别在氢化钠作用下与N-Boc-4-羟基哌啶反应,得到了与预期结构不同的产物.该产物的结构经1H NMR,13C NMR,LC-MS分析表明,其并非为原料2-(2-硝基苯氧基)-1-溴乙烷与N-Boc-4-羟基哌啶发生Williamson反应生成预期的混合醚,而是芳环上的烷氧基被取代的异常产物.根据这个实验结果,推测上述反应的可能机理是发生了芳环上的亲核取代反应.%The unexpected product from reaction of 2-(2-nitrophenoxy)-1-bromoethane or 3-(2-nitro-phenoxy)-1-bromopropane with N-Boc-4-hydroxypiperidine was obtained and the data of 1H NMR, 13C NMR and LC-MS of the product indicated that no Williamson reaction happened, instead, the alkyloxy in alkyloxy-nitrobenzene was substituted by N-Boc-4-hydroxypiperidine.Based on the fact, possible mechanism of the reaction was discussed.

  5. Identificación de la secuencia del gen de la subunidad catalítica de la telomerasa en Plasmodium falciparum.

    Directory of Open Access Journals (Sweden)

    Claudia Consuelo Rubiano

    2005-03-01

    Full Text Available lntroducción. La enzima telomerasa participa en la regulación de la longitud de los telómeros al sintetizar nuevas repeticiones teloméricas que compensan las pérdidas en cada ronda de replicación del ADN. Por esta razón, el bloqueo de su actividad se plantea como un posible blanco de acción para detener el crecimiento de células con altas tasas de crecimiento. Tal es el caso de Plasmodium falciparum, parásito causante de la forma más grave de paludismo humano, en el cual se sabe que hay actividad de telomerasa pero no se tiene información sobre la enzima misma. Metodología. Para hacer un acercamiento al estudio de la telomerasa en P. falciparum, se realizó un alineamiento múltiple de las secuencias de la subunidad catalítica de la telomerasa disponibles en bases de datos y se obtuvo una secuencia consenso, la cual se comparó con las secuencias generadas en el proyecto de genoma de P. falciparum. Se encontró una secuencia que podría corresponder a parte del gen de la telomerasa de P. falciparum. Para comprobarlo, se diseñaron iniciadores que se utilizaron en ensayos de amplificación sobre el ADN y el ARN del parásito. Resultados. Se amplificaron fragmentos de ADN correspondientes a motivos conservados en las telomerasas y se detectó la presencia del ARNm mediante trascripción reversa y PCR sobre el ADNc generado. De esta manera, al combinar la utilización de herramientas de bioinformática y su posterior comprobación mediante técnicas de biología molecular, se obtuvo la secuencia del gen de la subunidad catalítica de la telomerasa en P. falciparum y se comprobó su presencia y trascripción en el parásito

  6. Ultrasound-assisted magnetic solid-phase extraction based ionic liquid-coated Fe3O4@graphene for the determination of nitrobenzene compounds in environmental water samples.

    Science.gov (United States)

    Cao, Xiaoji; Shen, Lingxiao; Ye, Xuemin; Zhang, Feifei; Chen, Jiaoyu; Mo, Weimin

    2014-04-21

    An ultrasound-assisted magnetic solid-phase extraction procedure with the [C7MIM][PF6] ionic liquid-coated Fe3O4-grafted graphene nanocomposite as the magnetic adsorbent has been developed for the determination of five nitrobenzene compounds (NBs) in environmental water samples, in combination with high performance liquid chromatography-photodiode array detector (HPLC-PDA). Several significant factors that affect the extraction efficiency, such as the types of magnetic nanoparticle and ionic liquid, the volume of ionic liquid and the amount of magnetic nanoparticles, extraction time, ionic strength, and solution pH, were investigated. With the assistance of ultrasound, adsorbing nitrobenzene compounds by ionic liquid and self-aggregating ionic liquid onto the surface of the Fe3O4-grafted graphene proceeded synchronously, which made the extraction achieved the maximum within 20 min using only 144 μL [C7MIM][PF6] and 3 mg Fe3O4-grafted graphene. Under the optimized conditions, satisfactory linearities were obtained for all NBs with correlation coefficients larger than 0.9990. The mean recoveries at two spiked levels ranged from 80.35 to 102.77%. Attributed to the convenient magnetic separation, the Fe3O4-grafted graphene could be recycled many times. The proposed method was demonstrated to be feasible, simple, solvent-saving and easy to operate for the trace analysis of NBs in environmental water samples.

  7. Electrochemical degradation of nitrobenzene by anodic oxidation on the constructed TiO2-NTs/SnO2-Sb/PbO2 electrode.

    Science.gov (United States)

    Chen, Yong; Li, Hongyi; Liu, Weijing; Tu, Yong; Zhang, Yaohui; Han, Weiqing; Wang, Lianjun

    2014-10-01

    The interlayer of Sb-doped SnO2 (SnO2-Sb) and TiO2 nanotubes (TiO2-NTs) on Ti has been introduced into the PbO2 electrode system with the aim to reveal the mechanism of enhanced electrochemical performance of TiO2-NTs/SnO2-Sb/PbO2 electrode. In contrast with the traditional Ti/SnO2-Sb/PbO2 electrode, the constructed PbO2 electrode has a more regular and compact morphology with better oriented crystals of lower size. The TiO2-NTs/SnO2-Sb interlayer prepared by electrodeposition process improves PbO2 coating structure effectively, and enhances the electrochemical performance of PbO2 electrode. Kinetic analyses indicated that the electrochemical oxidation of nitrobenzene on the PbO2 electrodes followed pseudo-first-order reaction, and mass transport was enhanced at the constructed electrode. The accumulation of nitrocompounds of degradation intermediates on constructed electrode was lower, and almost all of the nitro groups were eliminated from aromatic rings after 6h of electrolysis. Higher combustion efficiency was obtained on the constructed TiO2-NTs/SnO2-Sb/PbO2 electrode. The intermediates of nitrobenzene oxidation were confirmed by IC and GC/MS.

  8. Abundância e distribuição das larvas de peixes no Lago Catalão e no encontro dos rios Solimões e Negro, Amazonas, Brasil Abundance and distribution of fish larvae in Catalão Lake and in the confluence of the Solimões and Negro River, Amazon, Brazil

    Directory of Open Access Journals (Sweden)

    Rosseval Galdino Leite

    2006-12-01

    Full Text Available A abundância e a distribuição mensal de larvas de peixes no Lago Catalão, situado próximo ao encontro dos rios Solimões e Negro, foram avaliadas entre os meses de janeiro e maio de 2001. As amostras foram coletadas com uma rede de ictioplâncton cônico-cilíndrica (350 µm de malha, Ø 0,3 m e 2 m de comprimento, com um fluxômetro acoplado na boca da rede para a obtenção do volume de água filtrado pela mesma. As variáveis categóricas consideradas foram: posição no lago (margem e centro, profundidade (superfície e fundo e turno (diurno e noturno; tendo sido realizada a Análise Fatorial de Correspondência (AFC usando a densidade larval (larvas. m-3 como variável resposta e os meses como descritores. A AFC discriminou a ocorrência de larvas por unidade experimental entre o mês de janeiro e os demais meses, com 58,15% de inércia, e a densidade larval mudou conforme a posição no lago e o período do dia. A maior parte das larvas era protolarva e alimentava-se na margem, tanto na superfície quanto no fundo do lago. Concluiu-se que o Lago Catalão é um importante berçário para as larvas dos peixes que desovam no rio Solimões e também para as larvas dos peixes que desovam no próprio lago.The abundance and monthly distribution of fish larvae in Catalão Lake, situated near the confluence of the Solimões and Negro River was evaluated between January and May 2001. The samples were obtained using a conical plankton net (350 µm, Ø 0.3, 2 m long, with a flow meter attached to the opening of the net. The categorical variables were: position in the lake (margin and center, period of the day (day and night and depth (surface and bottom. The analysis was made with Fatorial Correspondence Analyses (FCA using the larval density (larvae.m-3 as answer variable and the months as descriptors. The feeding activity of larvae was also studied. Most of them were protolarvae feeding in the margin of the lake, on the surface as well as on

  9. Dental caries and dental fluorosis in 7-12-year-old schoolchildren in Catalão, Goiás, Brazil Cárie e fluorose dentária em escolares de 7 a 12 anos de idade em Catalão, Goiás, Brasil

    Directory of Open Access Journals (Sweden)

    Priscila Ariede Petinuci Bardal

    2005-03-01

    Full Text Available INTRODUCTION: Over the last two decades, the prevalence of dental caries in children has decreased and the prevalence of dental fluorosis has increased. Knowledge on the epidemiologic conditions of a population is fundamental for the planning of health programs. OBJECTIVES: To determine the prevalence of dental caries and dental fluorosis among schoolchildren, in Catalão, Goiás, Brazil. METHODS: A random sample of 432 schoolchildren aged 7-12-years old was obtained. WHO (1997 criteria for dental caries and fluorosis diagnosis were used. RESULTS: The DMFT indexes were 0.97; 1.20; 1.80; 1.62; 2.40 and 2.51 for 7, 8, 9, 10, 11 and 12 years old, respectively. Analysis of dental fluorosis for the same ages presented higher prevalence at 12 years old and for the female gender. The percentage of questionable dental fluorosis (Dean's classification was 34.0%. Only 3% of the sample presented dental fluorosis with scores very mild, mild and moderate. CONCLUSIONS: The prevalence of caries in schoolchildren of Catalão, Goiás, Brazil, was low. In average, private schools showed better results than public schools; however, all schools presented a low DMFT index. In this study, dental fluorosis is not a public health problem and has not damaged dental esthetics.INTRODUÇÃO: Nas últimas duas décadas, a prevalência de cárie dentária tem diminuído e a prevalência de fluorose dentária tem aumentado. Para se planejar programas de saúde é fundamental conhecer o perfil epidemiológico das populações. OBJETIVOS: Determinar a prevalência de cárie dentária e fluorose dentária em escolares do município de Catalão, Goiás, Brasil. MÉTODOS: A amostra randomizada foi composta por 432 escolares de 7 a 12 anos de idade. Os critérios utilizados para determinar a prevalência de cárie dentária e fluorose seguiram a metodologia proposta pela OMS, 1997. RESULTADOS: Os valores do Índice CPOD foram de 0,97; 1,20; 1,80; 1,62; 2,40 e 2,51 para as idades de

  10. Relationship between acceleration of hydroxyl radical initiation and increase of multiple-ultrasonic field amount in the process of ultrasound catalytic ozonation for degradation of nitrobenzene in aqueous solution.

    Science.gov (United States)

    Zhao, Lei; Ma, Weichao; Ma, Jun; Wen, Gang; Liu, Qianliang

    2015-01-01

    The synergetic effect between ozone and ultrasound can enhance the degradation of nitrobenzene and removal efficiency of TOC in aqueous solution, and the degradation of nitrobenzene follows the mechanism of hydroxyl radical (OH) oxidation. Under the same total ultrasonic power input condition, the degradation rate of nitrobenzene (kNB), the volumetric mass transfer coefficient of ozone (kLa), and the initiation rate of OH (kOH) increases with introduction of additional ultrasonic field (1-4) in the process of ozone/ultrasound. The increasing amount of ultrasonic fields accelerates the decomposition of ozone, leading to the rapid appearance of the maximum equilibrium value and the decrease in the accumulation concentration of ozone in aqueous solution with the increasing reaction time. The increase in mass transfer of gaseous ozone dissolved into aqueous solution and the acceleration in the decomposition of ozone in aqueous solution synchronously contribute to the increase of kLa. The investigation of mechanism confirms that the increasing amount of ultrasonic fields yields the increase in cavitation activity that improves the mass transfer and decomposition of ozone, resulting in acceleration of OH initiation, which determines the degradation of nitrobenzene in aqueous solution.

  11. [A quantitative study of the consumption of antihypertensives in Management Area 5 of the ICS (Costa de Ponent). Institut Català de la Salut].

    Science.gov (United States)

    Font, M; Catalán, A; Madridejos, R

    1989-04-01

    The use of antihypertensive drugs (AHD) in the area n degrees 5 of the Institut Català de la Salut was evaluated for the period October 1986-December 1987. The unit of measure was the DDD (daily defined dose) per 1,000 population individuals per day. The overall use of AHD in 1987 was 49.31 DDDs/1,000 individuals/day; it was distributed among diuretics (53.5% of all AHD), beta-blockers (11.3%), and other AHD (35.2%). The most commonly prescribed drugs, by decreasing frequency order, were combinations of low ceiling diuretics with potassium sparing drugs, and of rauwolfia alkaloids with diuretics, followed by nifedipine, chlortalidone and furosemide. The interannual evaluation disclosed an increase of 18.6% in 1987 as compared with the preceding year, mostly at the expense of beta-blockers. On the other hand, there was a tendency to refrain from the use of fixed dose drug associations. This is a criterion of better use of antihypertensive therapy.

  12. Study of the catalytic properties of bacillus subtilis proteases Estudio de las propiedades catalíticas de las proteasas bacillus subtilis

    Directory of Open Access Journals (Sweden)

    Salcedo L.

    1998-06-01

    Full Text Available The catalytic properties of proteases isolated from the filtrate of submerged fermentation of Bacillus subtilis were investigated. Proteases present in the filtrate were determined to be of the serine protease type based on the use of specific protease inhibitors; ethylenediamintetraacetic acid (EDTA was used as a metalloprotease inhibitor, and phenylmethylsulfonylfluoride (PMSF was used as a serine protease inhibitor. Protease activity was highly stable in alkaline solutions and at high temperatures as well as in the presence of detergents. We propose that this protease preparation be used as biocomponent in detergent production.Se investigaron las propiedades catalíticas de las proteasas obtenidas del filtrado de cultivo de la bacteria Bacillus subtilis. Utilizando inhibidores específicos de proteasas se determinó que las proteasas presentes en el filtrado pertenecían al grupo de las serina proteasas. Se utilizó ácido etilendiaminatetraacético (EDTA como inhibidor de metaloproteasas, y fenilmetilsulfonil fluoruro (FMSF como inhibidor de serina proteasas. La actividad proteolítica fue altamente estable en soluciones alcalinas y a altas temperaturas, además tolero la presencia de detergentes. Se propone que estas proteasas sean utilizadas en calidad de biocomponente para la producción de detergentes.

  13. First Principle Study of Nitrobenzene-Adsorbed Graphene System%石墨烯吸附有机分子硝基苯性质的第一性原理研究

    Institute of Scientific and Technical Information of China (English)

    赵银昌; 戴振宏; 隋鹏飞; 张小玲; 张加东; 王森; 刘兵; 徐雷

    2013-01-01

    Based on first principle calculation,we have studied the properties of nitrobenzene-adsorbed graphene system.There is large adsorption energy in case of nitrobenzene being parallel to graphene substrate,while relative small adsorption energy is gained when the adsorbed molecule is perpendicular to graphene plane.At the same,in parallel case a slight lattice expansion is generated by adsorption interaction,in contrast to a weak lattice shrink produced by electron transferred from graphene to nitrobenzene in the perpendicular case.Due to relative strong interaction between nitro group and graphene,a doping state emerges when nitrobenzene is adsorbed on graphene plane.This provides a theoretical support to use of the graphene system as a chemical sensor of nitrobenzene molecules.%基于量子力学的第一性原理,我们计算了石墨烯吸附有机分子硝基苯的特性.在吸附体系中,吸附分子平面平行于石墨烯衬底时吸附能最大,同时此吸附导致衬底晶格微弱的膨胀.吸附分子平面垂直石墨烯吸附时,吸附能较小,且衬底晶格有微弱的收缩.由于硝基和石墨烯之间较强的相互作用,吸附结构的能带中出现明显的掺杂态.这说明了石墨烯可以作为有机分子硝基苯的化学传感器件之一.

  14. Regioselective synthesis of 2H-indazoles using a mild, one-pot condensation-Cadogan reductive cyclization.

    Science.gov (United States)

    Genung, Nathan E; Wei, Liuqing; Aspnes, Gary E

    2014-06-06

    An operationally simple and efficient one-pot synthesis of 2H-indazoles from commercially available reagents is reported. Ortho-imino-nitrobenzene substrates, generated via condensation, undergo reductive cyclization promoted by tri-n-butylphosophine to afford substituted 2H-indazoles under mild reaction conditions. A variety of electronically diverse ortho-nitrobenzaldehydes and anilines were examined. To further extend the scope of the transformation, aliphatic amines were also employed to form N2-alkyl indazoles selectively under the optimized reaction conditions.

  15. Solvent-induced assembly of two helical Eu(III) metal-organic frameworks and fluorescence sensing activities towards nitrobenzene and Cu2+ ions

    Science.gov (United States)

    Ma, Ranran; Chen, Zhiwei; Wang, Suna; Yao, Qingxia; Li, Yunwu; Lu, Jing; Li, Dacheng; Dou, Jianmin

    2017-08-01

    Two helical Eu(III) metal-organic frameworks, namely, {[Eu(L)(DMF)(H2O)]·0.5DMF}n (1) and [Eu(L)(DEF)(H2O)]n (2) (H3L=3,5-bis(2-carboxylphenoxy)benzoic acid, DMF=N,N-dimethylformamide, DEF=N,N-diethylformamide), have been solvothermally synthesized in different solvents, respectively. Both complexes possess helical structures through the connectivity of Eu atoms and phenolic-oxygen containing branches of the flexible multicarboxylate ligand. Based on different helices, these two complexes exhibited hexagonal and tetragonal channels, respectively. Both complexes possess (3,6)-connected (4.62)2(42.610.83) topology but with different long Schlafli symbol. The solvent plays an important role in the formation of the final frameworks. Both complexes can sensitively and selectively detect nitrobenzene and Cu2+ ions.

  16. catena-Poly[(μ2-3-carboxy-5-nitrobenzoato(μ3-5-nitrobenzene-1,3-dicarboxylato(1,10-phenanthrolinegadolinium(III

    Directory of Open Access Journals (Sweden)

    Zhi-Li Fang

    2010-10-01

    Full Text Available The crystal structure of the title complex, [Gd(C8H3NO6(C8H4NO6(C12H8N2]n, contains polymeric chains made up of GdIII atoms, 1,10-phenanthroline and fully or half-deprotonated 5-nitrobenzene-1,3-dicarboxylic acid (H2L ligands. The GdIII atom is coordinated in a distorted bicapped trigonal-prismatic fashion by six O atoms from two HL− and three L2− ligands, and by two N atoms from the 1,10-phenanthroline ligand. The L2− ligands bridge the Gd–phenanthroline units, forming chains running parallel to [100]. O—H...O hydrogen bonding as well as π–π stacking interactions with an interplanar distance of 3.599 (2 Å assemble neighboring polymeric chains.

  17. 1-Chloromethyl-3-nitrobenzene

    Directory of Open Access Journals (Sweden)

    Islam Ullah Khan

    2010-03-01

    Full Text Available In the title molecule, C7H6ClNO2, the plane of the nitro group and the direction of the chloromethyl group are twisted away from the benzene ring, forming dihedral angles of 8.2 (3 and 67.55 (12°, respectively. In the crystal structure, weak intermolecular C—H...O interactions link the molecules into corrugated sheets parallel to the bc plane.

  18. Development and validation of a sensitive UPLC-MS/MS instrumentation and alkaline nitrobenzene oxidation method for the determination of lignin monomers in wheat straw.

    Science.gov (United States)

    Zheng, Mengjing; Gu, Shubo; Chen, Jin; Luo, Yongli; Li, Wenqian; Ni, Jun; Li, Yong; Wang, Zhenlin

    2017-06-15

    A method to determine the lignin monomers (p-hydroxybenzaldehyde, vanillin and syringaldehyde) in plant cell wall of wheat internode was developed and validated using a high-throughput nitrobenzene oxidation step and ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) for quantification. UPLC analyses were carried out using an reversed phase C18 column (ACQUITY UPLC BEH, 1.7μm, 2.1×100mm) and gradient elution with water and acetonitrile. This method was completely validated in terms of analyzing speed, linearity, sensitivity, limits of detection (LODs) and limits of quantification (LOQs).The three lignin monomers were successfully separated within 6min and only 2min were required to regain its equilibrium. The method linearity with regression coefficients values (R2) greater than 0.997. Additionally, LODs ranged from 0.21 to 0.89μgL(-1) and LOQs ranged from 0.69 to 2.95μgL(-1). The applicability of this analytical approach for determining the three lignin monomers was confirmed by the successful analysis of real samples of wheat stem internodes. The nitrobenzene oxidation method was used for the analysis of lignin monomers. We have optimized the treatment temperature (170°C, 1h) and realized the high-throughput using the microwave digestion instrument. Recovery of this extraction method ranged from 68.4% to 77.7%. The analysis result showed that the guaiacyl unit (G) was the major component of lignin and there was a higher content of the syringyl unit (S) than that of the hydroxybenzyl unit (H). Copyright © 2017. Published by Elsevier B.V.

  19. Inventary of the Sponge Fauna of the cemitério Paleolake, Catalão, Goiás, Brazil

    Directory of Open Access Journals (Sweden)

    Vanessa de Souza Machado

    2012-03-01

    Full Text Available The Cemitério Paleolake, Catalão, Goiás, is a lacustrine deposit that is rich in spicules of continental sponges. These spicules, which are present in three sections (1-3, were analyzed for the taxonomic identification of the species in order to reconstruct the late Quaternary palaeoenvironment. An indigenous assemblage of lentic sponges was found, consisting of Metania spinata (Carter 1881, Dosilia pydanieli Volkmer-Ribeiro (1992, Radiospongilla amazonensis Volkmer-Ribeiro and Maciel (1983, Trochospongilla variabilis Bonetto and Ezcurra de Drago (1973, Corvomeyenia thumi (Traxler 1895, Heterorotula fistula Volkmer-Ribeiro and Motta (1995, plus Corvoheteromeyenia australis (Bonetto and Ezcurra de Drago 1966, which here has its first record in an assemblage formed by biosiliceous deposits. Furthermore, at the base of the sections, spicules of sponges from lotic environments were detected, including Corvospongilla seckti Bonetto and Ezcurra de Drago (1966, Oncosclera navicella (Carter 1881 and Eunapius fragilis (Leidy 1851, which suggests a contribution from flowing water. We identified 25 spongofacies horizons caused by sponge assemblages typical of a lentic environment, dated from at least 39,700 years BP., and currently occurring in lakes typical of the Cerrado Biome.O Paleolago Cemitério, Catalão, Goiás, é um depósito lacustre rico em espículas de esponjas continentais. Essas espículas, que estão presentes em três seções (1-3, foram analisadas para identificação taxonômica das espécies, a fim de reconstruir o paleoambiente do Quaternário tardio. Foi encontrada uma assembleia nativa de esponjas lênticas, consistindo de Metania spinata (Carter 1881, Dosilia pydanieli Volkmer-Ribeiro (1992, Radiospongilla amazonensis Volkmer-Ribeiro e Maciel (1983, Trochospongilla variabilis Bonetto e Ezcurra de Drago (1973, Corvomeyenia thumi (Traxler 1895, Heterorotula fistula Volkmer-Ribeiro e Motta (1995, acrescida de Corvoheteromeyenia

  20. Produção de massa de células permeabilizadas de Kluyveromyces lactis e atividade catalítica da bgalactosidase

    Directory of Open Access Journals (Sweden)

    Edimar A . F. Fontes

    2008-12-01

    Full Text Available A produção de massa de célula permeabilizada de Kluyveromyces lactis contendo a enzimagalactosidase e sua atividade catalítica na hidrólise de lactose foi realizada. Para obtenção da massa de célula permeabilizada, células foram produzidas, crescendo em soro de leite UF estéril. Para promover a permeabilização da membrana, células foram tratadas com uma solução etanol 50% para facilitar o contato entre a enzima e o substrato no processo de hidrólise da lactose. A atividade catalítica da enzima na hidrólise de lactose foi obtida pela relação linear entre a velocidade de reação e peso seco em mg de célula permeabilizada. A massa de 1mg de células permeabilizadas equivaleu a 0,32 unidades de atividade de enzima. O efeito da suspensão de célula permeabilizada na velocidade inicial de reação foi estudado utilizando diferentes concentrações de lactose (1, 40, 100 e 140 mM e suspensões de células permeabilizadas que variaram de 0,1 a 3 mg/ml. As reações foram acompanhadas no espectofotômetro DU em 510nm, que forneceu uma curva da variação de absorbância com o tempo de reação. A inclinação da reta apresentada por cada curva correspondeu as velocidades iniciais para cada concentração de célula permebilizada e de lactose. Foi utilizado nessa análise um reagente colorimétrico GOP-PAP que reagiu especificamente com a glicose presente no meio. Para conversão da leitura de absorvância em unidades de mM glicose, foi feita uma curva padrão de glicose. A concentração de 1mg/ml de célula permeabilizada adicionada à mistura de reação, foi selecionada pela sua relação linear com a velocidade de reação para concentrações mínimas (1 mM e extremas (140 mM de lactose. Valores abaixo de 1mg/ml foram apropriados para a reação linear entre velocidade e concentração inicial de enzima.

  1. Oxidación catalítica de diclorometano sobre Pd o Ni soportados en óxidos sol-gel

    Directory of Open Access Journals (Sweden)

    Leidy Marcela Martínez

    2004-01-01

    Full Text Available Se sintetizaron catalizadores sol-gel basados en paladio o níquel soportados en γ-alúmina, sílica ácida, circonia sulfatada y titania sulfatada. Los catalizadores resultantes se caracterizaron por difracción de rayos X y adsorción de nitrógeno y se evaluaron en la oxidación catalítica de diclorometano determinando el efecto de varios parámetros, entre los que se encuentran el método de síntesis, la temperatura y la acidez del soporte. El mejor catalizador (0,5% Pd impregnado en titania sulfatada se sometió a pruebas de durabilidad a 300 y 350 ºC durante 48 h. Bajo las condiciones estudiadas, los catalizadores impregnados exhibieron mayor actividad que los cogelados y los catalizadores con Pd mostraron altas conversiones principalmente a CO2 y HCl. La actividad de los catalizadores aumentó con la temperatura. Aunque los soportes γ- alúmina sol-gel y titania sulfatada también fueron activos para la reacción, una desventaja de la alúmina y la titania como soportes es la formación de trazas de CO. Los resultados indican que los catalizadores más activos y selectivos son bifuncionales. Esto es, para la descomposición de diclorometano a CO2 y HCl se requieren sitios metálicos y ácidos.

  2. Evaluación de la corrosión de un acero embebido en morteros adicionados con catalizador de craqueo catalítico usado (FCC

    Directory of Open Access Journals (Sweden)

    Silvia Izquierdo García

    2013-01-01

    Full Text Available En el presente artículo se analiza el desempeño frente a la corrosión de morteros de cemento adicionados con un residuo de la industria petroquímica en ambientes contaminados con cloruros (Cloruro de Sodio, NaCl 3.5% y/o Anhídrido Carbónico, CO2 (3% CO2, 65% HR y 25°C. Se utilizó un residuo denominado catalizador usado de craqueo catalítico (FCC, procedente de una refinería colombiana; este material tiene un alto contenido de sílice y alúmina, morfología parcialmente amorfa y posee una alta reactividad. Para el estudio, se prepararon morteros de cemento Portland ordinario con el 12% de FCC como reemplazo de cemento, tanto simples como reforzados. Se evaluó el potencial y la corriente de corrosión y complementariamente, en los especímenes no reforzados, se determinó la absorción total, penetración de cloruros, resistividad y frente de carbonatación. A partir de los resultados, se concluye que la adición del 12% de FCC al cemento reduce la permeabilidad a cloruros y la susceptibilidad a la carbonatación del mortero en órdenes hasta del 50%, así mismo genera un incremento del 128% en la resistividad del mortero. Los aceros embebidos en los morteros adicionados presentaron velocidades de corrosión más bajas, particularmente en presencia de iones cloruros.

  3. Correlación entre las propiedades morfológicas, estructurales y catalíticas de soluciones sólidas nanoestructuradas de GdxCe1-xO2-x/2

    OpenAIRE

    Muñoz, Fernando Francisco

    2014-01-01

    En la presente tesis de doctorado se llevó a cabo el estudio de soluciones sólidas nanoestructuradas de ceria dopada con gadolinia, GdxCe1-xO2-x/2 (GDC), con el objetivo principal de correlacionar las propiedades morfológicas, estructurales, óxido-reductoras y catalíticas de este tipo de compuestos. El control de estas propiedades es fundamental para su aplicación en dispositivos tecnológicos, ya sea como catalizadores para diferentes reacciones o como materiales para la generación de energía...

  4. Modificación de arcillas colombianas con pilares mixtos AI-Fe, y su evaluación en la oxidación catalítica de fenol en solución acuosa diluida

    Directory of Open Access Journals (Sweden)

    Luis A. Galeano

    2010-09-01

    Full Text Available La legislación ambiental es particularmente restrictiva respecto a la disposición de contaminantes biorrefractarios presentes en aguas residuales. Las arcillas pilarizadas tienen gran versatilidad para ajustarse a reacciones de interés ambiental, entre otras. En el presente estudio se logran modificar arcillas de origen colombiano con soluciones de pilares mixtos Al-Fe, las cuales muestran un excelente desempeño en la oxidación catalítica de soluciones acuosas con contenidos medios de carbono orgánico total COT (36 mg C/L.

  5. Efeito dos fosfatos naturais alvorada, catalão, patos e arad na produção de massa seca de milho em casa-de-vegetação Effect of Alvorada, Catalão, Patos and Arad phosphates in dry matter production of maize greenhouse conditions

    Directory of Open Access Journals (Sweden)

    M.S. de CAMARGO

    1998-01-01

    Full Text Available A comparação do comportamento de fosfatos naturais foi feita com a avaliação da produção de massa seca em plantios de milho em vasos (3kg, contendo um Podzólico Vermelho Amarelo, sob condições controladas de casa-de-vegetação. Quatro fosfatos naturais (Alvorada, Catalão, Patos e Arad foram utilizados em três doses de P (100, 150, e 200 mg kg-1, calculadas com base no fósforo solúvel extraído pelas solubilidades das relações fosfato: solução extratora (g de fosfato mL-1 de ácido cítrico 2%: 1:100; 1:200 e 1:400. O fosfato Alvorada apresentou a maior produção de massa seca inicial, superando os demais fosfatos naturais, inclusive o superfosfato triplo, e não diferindo do fosfato Arad no segundo plantio. A solubilidade em ácido cítrico 2% (1:100 é um importante parâmetro para predição do comportamento de fosfatos naturais de diferentes origens geológicas. A recomendação de adubação fosfatada utilizando quantidades iguais de fosfatos naturais não é adequada, pois têm comportamento diferenciado devido às variações na composição química e mineralógica.A comparison between natural phosphates was performed by dry matter production in maize sowed pots (3kg containing an Ultissol, under greenhouse conditions. Four natural phosphates (Alvorada, Catalão, Patos and Arad were applied at the rates of 100, 150 and 200 mg P kg-1 soil, that were calculated by soluble phosphorus extracted in citric acid 2%: 1:100; 1:200 e 1:400 (g phosphate mL-1 citric acid 2%. Alvorada phosphate exhibited best dry matter production as compared to the other sources. The solubility in citric acid 2% (1:100 was important to predict the performance of natural phosphates. The recommendation of equal quantities of natural phosphate from distinct origins is not adequate because they promote different responses with respect to dry matter production.

  6. The crystal structure, luminescence and nitrobenzene-sensing properties of a two-dimensional Mn(II) coordination polymer based on 2,6-bis(imidazol-1-yl)pyridine.

    Science.gov (United States)

    Wang, Yin-Lin; Long, Ling-Liang; Zhang, Jin-Fang

    2015-06-01

    A two-dimensional Mn(II) coordination polymer (CP), poly[bis[μ2-2,6-bis(imidazol-1-yl)pyridine-κ(2)N(3):N(3')]bis(thiocyanato-κN)manganese] [Mn(NCS)2(C11H9N5)2]n, (I), has been obtained by the self-assembly reaction of Mn(ClO4)2·6H2O, NH4SCN and bent 2,6-bis(imidazol-1-yl)pyridine (2,6-bip). CP (I) was characterized by FT-IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. The crystal structure features a unique two-dimensional (4,4) network with one-dimensional channels. The luminescence and nitrobenzene-sensing properties were explored in a DMF suspension, revealing that CP (I) shows a strong luminescence emission and is highly sensitive for nitrobenzene detection.

  7. Synthesis of [Pd(dmba)(N{sub 3})(PPh{sub 3})] and its use in catalytic processes involving the reductive n-carbonylation of nitroarenes to carbamates and in the synthesis of urea derivatives; Sintese e emprego do ciclometalado [Pd(dmba)(N{sub 3})(PPh{sub 3})] em processos cataliticos envolvendo a n-carbonilacao redutiva de nitroarenos a carbamatos e na sintese de derivados da ureia

    Energy Technology Data Exchange (ETDEWEB)

    Caires, Antonio Carlos Favero [Universidade de Mogi das Cruzes, SP (Brazil). Centro Interdisciplinar de Investigacao Bioquimica; Mauro, Antonio Eduardo; Moro, Antonio Carlos; Legendre, Alexandre de Oliveira; Ananias, Sandra Regina [UNESP, Araraquara, SP (Brazil). Inst. de Quimica]. E-mail: mauro@iq.unesp.br

    2006-07-15

    This work deals with the use of the cyclomethalade compound [Pd(dmba)(N{sub 3})(PPh{sub 3})] in homogeneous catalytic processes comprising the reductive N-carbonylation of nitrobenzene and p-nitrotoluene to ethyl-phenylcarbamate and ethyl-4-methylphenylcarbamate, respectively. The cyclopalladated compound was also employed in the synthesis of urea derivatives by reacting p-nitrotoluene and m-nitrotoluene, respectively, with p-toluidine and and m-chloroaniline. (author)

  8. Gasificación catalítica de lodos de aguas residuales. // Catalytic gasification of residual waters muds.

    Directory of Open Access Journals (Sweden)

    L. M. García Rojas

    2005-05-01

    Full Text Available A partir de la necesidad de encontrar nuevas alternativas energéticas, se estudia en este trabajo la posibilidad de reducir agran escala la cantidad de alquitranes que acompaña al gas obtenido de la gasificación en lecho fluidizado de los lodos delas depuradoras de aguas residuales, este estudio conduce a una posible utilización de este gas en la generación deelectricidad, Para propiciar tal reducción se han empleado catalizadores secundarios reemplazando, en parte ocompletamente, la arena utilizada como agente fluidizante. Además la presencia de vapor de agua, que puede actuar comoreactante para el reformado de hidrocarburos, también puede ser beneficiosa a la hora de reducir la cantidad de alquitranesen el gas, por lo que, junto con la sustitución de la arena por un catalizador, se han realizado experimentos alimentandovapor de agua al reactor.Palabras claves: Gasificación, lecho fluidizado y lodos.____________________________________________________________________________Abstract.Starting from the necessity of finding new energy alternatives, it is presented in this paper the possibility to reduce in greatscale the quantity of tars that accompanies the gas obtained of the gasification in fluidized bed of muds in residual waters,this study leads to a possible use of this gas in the electricity generation, For propitiate such reduction a secondary catalystshas been used replacing, partly or completely, the sand used as fluidity agent. Also the presence of water steam that can actas reactant for the hydrocarbons reformed, it can also be beneficial when reducing the quantity of tars in the gas, for that,together with the substitution of sand for a catalyst, it have been carried out experiments feeding water steam to the reactor.Key words: Catalytic gasification, fluidity channel, muds.

  9. 超声波/零价铁协同降解硝基苯的机理研究%Mechanism of nitrobenzene degradation by ultrasound/zero-valent iron system

    Institute of Scientific and Technical Information of China (English)

    李天鹏

    2011-01-01

    对超声波/零价铁协同降解硝基苯的作用机理进行了研究.结果表明,超声波与零价铁联用时有明显的协同效应.超声辐照有利于铁屑转化为Fe2+,并进一步氧化为Fe3+,不规整铁屑对超声空化有促进作用,在超声波/零价铁体系中存在Fenton反应,通过产生大量的·OH降解硝基苯,该氧化过程是硝基苯降解的主要途径之一.%The mechanism of nitrobenzene degradation by ultrasound/aero-valent iron system was studied.The results showed that, ultrasound and zero-valent iron had obvious synergistic effect when they were used combinedly. Ultrasound irradiation could help convert iron scrap into Fe2+ and further oxidized it to Fe3+,meanwhile, irregular iron scrap could promote ultrasonic cavitation. As Fenton reaction existed in the ultrasound/zero-valent iron system, large amount of ·OH was produced, which could degrade nitrobenzene. The above oxidation process was one of the main ways for nitrobenzene degradation.

  10. Reduction of Nitroaromatic Compounds on the Surface of Metallic Iron: Quantum Chemical Study

    Directory of Open Access Journals (Sweden)

    Jerzy Leszczynski

    2002-07-01

    Full Text Available Abstract: The initial reduction steps of nitroaromatic compounds on the surface of metallic iron have been studied theoretically using nitrobenzene (NB as a representative of nitroaromatic compounds. The quantum chemical cluster approximation within the semiempirical Neglect of Diatomic Differential Overlap for Metal Compounds method was applied to model the Fe(110 crystallographic surface, taken as a representative reactive surface for granular iron. This surface was modeled as a 39-atom two-layer metal cluster with rigid geometry. The associative and dissociative adsorption of nitrobenzene was considered. Based on our quantum chemical analysis, we suggest that the direct electron donation from the metal surface into the π* orbital of NB is a decisive factor responsible for subsequent transformation of the nitro group. Molecularly adsorbed NB interacts with metal iron exclusively through nitro moiety oxygens which occupy tri-coordinated positions on surface The charge transfer from metal to NB of approximately 2 atomic units destablizes the nitro group. As a result, the first dissociation of the N-O bond goes through a relatively low activation barrier. The adsorbed nitrosobenzene is predicted to be a stable surface species, though still quiet labile.

  11. Concreto nanoligado a base de sílica fundida para aplicação no riser de unidade de craqueamento catalítico fluido

    Directory of Open Access Journals (Sweden)

    E. Prestes

    2015-03-01

    Full Text Available O agregado de sílica fundida é uma matéria-prima que se mostra adequada para o desenvolvimento de concretos para aplicação em riser de unidade de craqueamento catalítico fluido de petróleo (UFCC. A sua baixa densidade aparente e reduzida condutividade térmica contribuem, respectivamente, para a diminuição do peso da estrutura refratária e maior eficiência térmica do processo. Já o seu coeficiente de expansão linear de 0,55 x 10-6/ºC, extremamente reduzido, garante uma excelente resistência ao choque térmico. Contudo, para as condições de operação em riser, estas características precisam estar aliadas a um baixo desgaste por erosão. Sendo assim, um concreto nanoligado a base de sílica fundida foi desenvolvido buscando-se a minimização do desgaste por erosão. Duas composições foram testadas combinando-se os agregados de sílica fundida e alumina tabular. Verificou-se que as tensões geradas pelo "mismatch" de expansão térmica entre os agregados resultaram na formação de microtrincas, reduzindo consideravelmente as propriedades termomecânicas do material. Um menor dano foi verificado para a composição onde a alumina tabular foi adicionada somente nas frações mais finas de agregado. Nesta, a incorporação de um aditivo sinterizante favoreceu uma maior densificação em baixa temperatura, possibilitando otimizar a resistência à erosão e ao choque térmico. O valor médio de volume erodido obtido após queima a 815 ºC foi de 4,8 cm3. Em comparação com os 6 cm3 especificados pela indústria petroquímica brasileira para produtos refratários de alta alumina com densidade aparente superior a 2,60 g/cm3, pode-se afirmar que o resultado obtido foi muito promissor. O concreto nanoligado a base de sílica fundida que foi desenvolvido mostrou ser uma excelente opção para aplicação em riser de UFCC.

  12. Treatment of Wastewater Containing Nitrobenzene and Aniline by Biofilter with Immobilized Microorganisms%固定化微生物强化生物滤池处理硝基苯和苯胺废水

    Institute of Scientific and Technical Information of China (English)

    申运栓; 王中友; 叶正芳; 唐鹏; 许晓峰; 曲绍业; 曲建菊; 张戈; 郭玉凤

    2009-01-01

    利用复合微生物菌群BCP35,对自制的大孔功能化载体FPU进行微生物的固定化,并与厌氧生物滤池和好氧生物滤池联用处理含高浓度硝基苯和苯胺的废水,研究了固定化微生物强化生物滤池处理污染物的运行效果、硝基苯和苯胺的降解特征,比较了固定化微生物和游离态微生物的除污性能,同时分析了载体上微生物的状态和生物量.结果表明,固定化微生物强化生物滤池工艺对硝基苯、苯胺具有很好的去除效果,对硝基苯和苯胺的降解率可分别达到99.8%和99.9%;同时生物滤池还对污染物浓度变化具有较强的抗冲击负荷能力;与游离态微生物相比,固定化微生物在去除COD、硝基苯、苯胺等方面更具优势;生物滤池内的微生物浓度较高,可达到38g/L.%The carrier FPU was immobilized with composite microorganisms BCP35 and was adopted to treat wastewater containing high concentration nitrobenzene and aniline in the anaerobic biofilter and aerobic biofiher. The operation effect of the biofilters with the immobilized microorganisms and the degradation of nitrobenzene and aniline were investigated. The pollutant removal efficiency of the immobilized microorganisms and the free microorganisms was compared, and the morphology and biomass of microorganisms on the cartier were analyzed. The results show that the biofilters with the immobilized microorganisms are effective in nitrobenzene and aniline removal. The removal rates of nitrobenzene and aniline are 99.8% and 99.9% respectively. The biofiters have strong resistance to shock loading. The immobilized microorganisms are more dominant in COD, nitrobenzene and aniline removal than the free microorganisms. The concentration of microorganisms in the biofiters is high, reaching 38 g/L.

  13. 超滤膜去除地下水中硝基苯的试验研究%Experimental Study on the Removal of Nitrobenzene in Groundwater by Ultrafiltration

    Institute of Scientific and Technical Information of China (English)

    赵玉鑫; 尹军; 王晓玲; 刘蕾

    2007-01-01

    为解决持久性有机污染物对地下水造成的污染,以硝基苯为研究对象,考察了超滤膜对硝基苯的去除效果及影响因素.试验结果表明,当进水硝基苯浓度为85 μg/L,超滤膜可以连续工作68 h,出水小于17 μg/L.地下水中铁、锰离子对去除效果没有显著影响.进水硝基苯浓度对去除效果有显著影响.当进水硝基苯浓度由85 μg/L上升至340 μg/L时,超滤膜连续工作时间急剧下降,仅为14 h;对由硝基苯引起的膜污染,2% CH3CH2OH清洗效果最佳.作为一项应急处理技术,该工艺可以保障小城镇地区饮水安全.%In order to solve the pollution of groundwater caused by persistent organic contaminants,the removal efficiency and affecting factors of nitrobenzene removal from groundwater by using ultrafiltration technology was investigated.The experimental results indicate that the ultrafiltration system can work continuously for 68 hours when initial concentration is 85μg/L,and the nitrobenzene concentration of outflow is less than 17μg/L.Fe and Mn in groundwater have no significant impact on the removal efficiency,but the effect of initial nitrobenzene concentration of inflow is obvious.The continuous operation time decrease sharply from 68 to 14 hours when nitrobenzene concentration is 340 μg/L.2% CH3CH2OH has the best performance for cleaning the fouling caused by nitrobenzene.As an urgent treatment technology,ultrafiltration technology could guarantee the security of drinking water for people living in rural area.

  14. Metal-organic framework UiO-67-coated fiber for the solid-phase microextraction of nitrobenzene compounds from water.

    Science.gov (United States)

    Zang, Xiaohuan; Zhang, Xi; Chang, Qingyun; Li, Sen; Wang, Chun; Wang, Zhi

    2016-07-01

    A sol-gel coating technique was applied for the preparation of a solid-phase microextraction fiber by coating the metal-organic framework UiO-67 onto a stainless-steel wire. The prepared fiber was explored for the headspace solid-phase microextraction of five nitrobenzene compounds from water samples before gas chromatography with mass spectrometric detection. The effects of the extraction temperature, extraction time, sample solution volume, salt addition, and desorption conditions on the extraction efficiency were optimized. Under the optimal conditions, the linearity was observed in the range of 0.015-12.0 μg/L for the compounds in water samples, with the correlation coefficients (r) of 0.9945-0.9987. The limits of detection of the method were 5.0-10.0 ng/L, and the recoveries of the analytes from spiked water samples for the method were in the range of 74.0-102.0%. The precision for the measurements, expressed as the relative standard deviation, was less than 11.9%.

  15. Application of Density Functional Theoretic Descriptors to Quantitative Structure-Activity Relationships with Temperature Constrained Cascade Correlation Network Models of Nitrobenzene Derivatives

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A temperature-constrained cascade correlation network(TCCCN), a back-propagation neural network(BP), and multiple linear regression(MLR) models were applied to quantitative structure-activity relationship(QSAR) modeling, on the basis of a set of 35 nitrobenzene derivatives and their acute toxicities. These structural quantum-chemical descriptors were obtained from the density functional theory(DFT). Stepwise multiple regression analysis was performed and the model was obtained. The value of the calibration correlation coefficient R is 0.925, and the value of cross-validation correlation coefficient R is 0.87. The standard error S=0.308 and the cross-validated(leave-one-out) standard error Scv=0.381. Principal component analysis(PCA) was carried out for parameter selection. RMS errors for training set via TCCCN and BP are 0.067 and 0.095, respectively, and RMS errors for testing set via TCCCN and BP are 0.090 and 0.111, respectively. The results show that TCCCN performs better than BP and MLR.

  16. Efficient removal of nitrobenzene and concomitant electricity production by single-chamber microbial fuel cells with activated carbon air-cathode.

    Science.gov (United States)

    Zhang, Enren; Wang, Feng; Zhai, Wenjing; Scott, Keith; Wang, Xu; Diao, Guowang

    2017-04-01

    Single-chamber microbial fuel cells (S-MFCs) with bio-anodes and activated carbon (AC) air-cathodes showed high nitrobenzene (NB) tolerance and NB removal with concomitant electricity production. The maximum power over 25Wm(-3) could be obtained when S-MFCs were operated in the NB loading range of 1.2-6.2molm(-3)d(-1), and stable electricity production over 13.7Wm(-3) could be produced in a NB loading range of 1.2-14.7molm(-3)d(-1). The present S-MFCs exhibited high NB removal performance with NB removal efficiency over 97% even when the NB loading rate was increased to 17.2molm(-3)d(-1). The potential NB reduced product (i.e. aniline) could also be effectively removed from influents. The findings in this study means that single-chamber MFCs assembled with pre-enriched bio-anodes and AC air-cathodes could be developed as effective bio-electrochemical systems to remove NB from wastewaters and to harvest energy instead of consuming energy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Synthesis of Pt-Loaded Self-Interspersed Anatase TiO2 with a Large Fraction of (001) Facets for Efficient Photocatalytic Nitrobenzene Degradation.

    Science.gov (United States)

    Wang, Wei-Kang; Chen, Jie-Jie; Li, Wen-Wei; Pei, Dan-Ni; Zhang, Xing; Yu, Han-Qing

    2015-09-16

    TiO2 is capable of directly utilizing solar energy for sustainable energy harvest and water purification. Facet-dependent performance of TiO2 has attracted enormous interests due to its tunable photocatalytic activity toward photoredox transformations, but information about the noble-metal-loaded TiO2 for its facet-dependent photocatalytic performance, especially in pollutant degradation systems, is limited. In this work, inspired by our previous theoretical calculations about the roles of the crystal surface in Pt-loaded TiO2 in its enhanced photocatalytic capacity, TiO2 nanocrystals with interspersed polyhedron nanostructures and coexposed (001) and (101) surfaces as a support of Pt nanoparticles are prepared in a simple and relatively green route. Also, their performance for photocatalytic degradation of nitrobenzene (NB), a model organic pollutant, is explored. The experimental results demonstrate that the NB photodegradation and photoconversion efficiencies are significantly enhanced by uniformly loading Pt nanoparticles on the crystal surfaces, but the Pt nanoparticles deposited on only the (101) surface have no contribution to the improved NB photodegradation. Furthermore, the liquid chromatography mass spectrometry results also show that NB photodegradation tends to proceed on the (001) surface of Pt/TiO2 for the generation of nitrophenol intermediates through the photooxidation pathway. This work provides a new route to design and construct advanced photocatalysts toward pollutant photoredox conversions and deepens our fundamental understanding about crystal surface engineering.

  18. Multifunctional uranyl hybrid materials: structural diversities as a function of pH, luminescence with potential nitrobenzene sensing, and photoelectric behavior as p-type semiconductors.

    Science.gov (United States)

    Song, Jian; Gao, Xue; Wang, Zhi-Nan; Li, Cheng-Ren; Xu, Qi; Bai, Feng-Ying; Shi, Zhong-Feng; Xing, Yong-Heng

    2015-09-21

    A series of uranyl-organic frameworks (UOFs), {[(UO2)2(H2TTHA)(H2O)]·4,4'-bipy·2H2O}n (1), {[(UO2)3(TTHA)(H2O)3]}n (2), and {[(UO2)5(TTHA) (HTTHA)(H2O)3]·H3O}n (3), have been obtained by the hydrothermal reaction of uranyl acetate with a flexible hexapodal ligand (1,3,5-triazine-2,4,6-triamine hexaacetic acid, H6TTHA). These compounds exhibited three distinct 3D self-assembly architectures as a function of pH by single-crystal structural analysis, although the used ligand was the same in each reaction. Surprisingly, all of the coordination modes of the H6TTHA ligand in this work are first discovered. Furthermore, the photoluminescent results showed that these compounds displayed high-sensitivity luminescent sensing functions for nitrobenzene. Additionally, the surface photovoltage spectroscopy and electric-field-induced surface photovoltage spectroscopy showed that compounds 1-3 could behave as p-type semiconductors.

  19. Prontidão à tecnologia: um estudo sobre a aplicação da Technology Readiness Index (TRI na cidade de Catalão, GO The Technology Readiness: A Study On The Implementation of The Technology Readiness Index (Tri In The Catalão City -Go

    Directory of Open Access Journals (Sweden)

    Solon Bevilacqua

    2011-12-01

    Full Text Available Este é um estudo descritivo e exploratório que objetivou identificar preliminarmente o nível de prontidão à tecnologia na cidade de Catalão, GO, a partir de uma amostra de 368 indivíduos. O estudo utilizou a técnica Technology Readiness Index (TRI, proposta por Parasuraman e Colby (2002. Após a realização das análises, verificou-se que, apesar de a estrutura da TRI ter apresentado alterações em relação ao estudo original, foi possível constatar a aplicabilidade da escala no contexto da cidade alvo, levantar o perfil da amostra investigada, bem como identificar o seu nível de prontidão à tecnologia, que apresentou características de consumidores "Pioneiros", além de levantar aspectos gerais para a realização de futuras pesquisas causais ou conclusivas. This is a descriptive and exploratory study which aimed at identifying preliminarily the level of technology readiness in Catalan-GO, from a sample of 368 individuals. The study used the Technology Readiness Index (TRI technique, proposed by Parasuraman and Colby (2002. After analysis completion, it was found that, although the structure of TRI had been different from the original study, it was possible to verify the measure applicability in the context of the city, to draw the profile of the sample investigated, as well as to identify its technology readiness level, which had presented characteristics of “Pioneer” consumers, besides to raise general aspects for the realization of future causal or conclusive research.

  20. Poverty Reduction

    OpenAIRE

    Ortiz, Isabel

    2007-01-01

    The paper reviews poverty trends and measurements, poverty reduction in historical perspective, the poverty-inequality-growth debate, national poverty reduction strategies, criticisms of the agenda and the need for redistribution, international policies for poverty reduction, and ultimately understanding poverty at a global scale. It belongs to a series of backgrounders developed at Joseph Stiglitz's Initiative for Policy Dialogue.

  1. La trayectoria de una reforma educativa global: el caso de la Nueva Gestión Pública en el sistema educativo catalán

    Directory of Open Access Journals (Sweden)

    Antoni Verger

    2015-09-01

    Full Text Available RESUMEN: La Nueva Gestión Pública (NGP es un programa de reforma del sector público que ha inspirado numerosos procesos de reforma educativa a nivel internacional. En el campo de la educación, la NGP ha cristalizado en políticas como la autonomía de centro, la profesionalización de las direcciones escolares, la evaluación estandarizada y los sistemas de rendición de cuentas de los docentes. En este artículo se analiza cómo y por qué la NGP ha sido adoptada y re-contextualizada en un escenario educativo del sur de Europa, como es Cataluña. Este artículo muestra que las razones por las que se ha adoptado la NGP en Cataluña no son tan diferentes de las existentes en otros países en los que estas políticas se han aplicado con anterioridad. Contra-intuitivamente, aunque la NGP es un programa de reforma del sector público históricamente vinculado a fuerzas conservadoras, en Cataluña, como ocurrió previamente en otros países del Centro y del Norte de Europa, la NGP ha sido aprobada y regulada con un gobierno de corte socialdemócrata. En todos estos lugares, los socialdemócratas han tendido a aproximarse a los postulados de la NGP como un intento de hacer frente a la crisis de legitimidad del Estado de bienestar y de los servicios públicos en particular. Sin embargo, la reforma educativa de NGP se ha promulgado y regulado de forma irregular en Cataluña. Razones de naturaleza política, institucional y económica, junto a las múltiples representaciones y reinterpretaciones que los policy-makers locales hacen de las políticas de NGP, explican por qué estas políticas han seguido una trayectoria que se podría calificar de errática y a momentos paradójica en el contexto analizado. A nivel empírico, el estudio se basa en, por un lado, entrevistas con responsables políticos y actores clave del sistema educativo catalán y, por el otro, análisis de informes oficiales, comunicados de prensa y marco normativo. El estudio de

  2. Síntese por electrospinning e caracterização microestrutural de fibras de óxido de cério dopadas com cobre para combustão catalítica de metano

    OpenAIRE

    2012-01-01

    Neste trabalho, objetivou-se produzir catalisadores a partir de fibras cerâmicas de óxido de cério (céria) usando o método de electrospinning e o estudo da influência de diferentes morfologias dos produtos formados na reação de combustão catalítica do metano. No processo experimental, foi preparada uma solução com os precursores nitrato de cério hexahidratado e acetato de cobre em álcool etílico e uma solução de PVB – polivinilbutiral na concentração 10% em álcool etílico. Para a produção das...

  3. Análisis contrastivo de las traducciones al español y catalán de The giraffe and the pelly and me de Roald Dalh

    Directory of Open Access Journals (Sweden)

    Mercedes Querol Julián

    2010-01-01

    Full Text Available En este estudio se hace una propuesta de análisis contrastivo de las traducciones en español y catalán de un libro infantil escrito originalmente en inglés. Desde una perspectiva multidisciplinar. Se consideran tanto las normas preliminares (aspectos externos al texto, como las operacionales (aspectos relacionados directamente con el texto. El análisis muestra como las desviaciones del original en muchos casos ayudan a construir la identidad de los personajes, la cual difiere en los tres libros, por tanto se prevee que la percepción de la historia por sus lectores también será diferente en las tres lenguas.

  4. La noche es oscura y alberga traducciones : Análisis contrastivo de la traducción de 'A Game of Thrones' al castellano y al catalán

    OpenAIRE

    Fuente Álvarez, Virginia de la

    2015-01-01

    El trabajo consiste en un análisis contrastivo de las traducciones al castellano y al catalán de A Game of Thrones, de George R. R. Martin. Haciendo hincapié en los problemas de traducción que representan los topónimos, los antropónimos, los nombres de la fauna y la flora y las armas, en un mundo ficticio con trazas de fantasía. Se han tratado los problemas de traducción teniendo en cuenta las teorías de Javier Franco Aixelá, Virgilio Moya y Lawrence Venuti El treball consisteix en una anà...

  5. La noche es oscura y alberga traducciones : Análisis contrastivo de la traducción de 'A Game of Thrones' al castellano y al catalán

    OpenAIRE

    Fuente Álvarez, Virginia de la

    2015-01-01

    El trabajo consiste en un análisis contrastivo de las traducciones al castellano y al catalán de A Game of Thrones, de George R. R. Martin. Haciendo hincapié en los problemas de traducción que representan los topónimos, los antropónimos, los nombres de la fauna y la flora y las armas, en un mundo ficticio con trazas de fantasía. Se han tratado los problemas de traducción teniendo en cuenta las teorías de Javier Franco Aixelá, Virgilio Moya y Lawrence Venuti El treball consisteix en una anà...

  6. Models de traducció literària i audiovisual en català col·loquial: el cas de «Jackie Brown» de Quentin Tarantino

    OpenAIRE

    Dídac Pujol

    2015-01-01

    Resum: Aquest article tracta dels models de traducció col·loquial cap al català en el cas de la versió doblada (1997), la versió subtitulada (1997) i el guió traduït (1998) de Jackie Brown (1997) de Quentin Tarantino. El nucli de l’article és l’anàlisi i la comparació de la fonètica, la morfologia, la sintaxi i el lèxic de cada traducció catalana, que s’emmarca en els models lingüístics i de traducció vigents en el període objecte d’estudi. La conclusió a la qual s’arriba és que les tres trad...

  7. Composition and abundance of fishes in the interface between open water and macrophyte banks, and the dynamics of this interface during morning and evening twilight, in lake Catalão, Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    Igor David da Costa

    2011-06-01

    Full Text Available This work studied the composition and abundance of the fishes that move between macrophyte banks and open water during the morning twilight (CM and afternoon twilight (CV. The collections were made using gillnets, along banks of Paspalum repens, at Catalão lake, in Amazonas, Brazil. A total of 222 individuals and 37 species were collected. Of these, 130 individuals were collected during the CM and 92 during the CV; 80 individuals were leaving during the CM and 40 individuals were leaving during the CV. Auchenipterus nuchalis, Pellona castelnaeana, Triportheus angulatus and T. albus were the most common and concentrated species collected in the CM and Pimelodus blochii was the most common species collected in the CV.

  8. La expresión y actividad catalítica diferencial de GDP-manosa pirofosforilasa influye en la producción de vitamina C en Myrciaria dubia “camu-camu”

    Directory of Open Access Journals (Sweden)

    Juan Castro Gómez

    2013-12-01

    Full Text Available Myrciaria dubia muestra una amplia variación en la producción de vitamina C (vit.C. Para entender las bases moleculares de esta variación, se determinó la relación del nivel de expresión genética y actividad de GDP-Manosa pirofosforilasa (GMP con la variación del contenido de vit.C en M. dubia. Las muestras fueron obtenidas de una colección de germoplasma. La vit.C se cuantificó por HPLC, la actividad de GMP se midió por  espectrofotometría. El ARN se purificó, el ADNc se sintetizó, amplificó, clonó y secuenció con técnicas estándares. La expresión del gen se midió mediante PCR en tiempo real. Las diferencias en el contenido de vit.C de las hojas, pulpa y cáscara dependieron de la expresión y actividad de GMP. Esta relación también se observó entre plantas que producen frutos con bajo y alto contenido de vit.C. En conclusión, Las hojas, pulpa y cáscara de M. dubia muestran diferencias significativas en el contenido de vit.C, el cual se atribuye a la expresión y actividad catalítica diferencial de la GMP. Asimismo, las plantas que producen frutos con diferencias marcadas en el contenido de vit.C en sus pulpas, también dependen del nivel de expresión y actividad catalítica de esta enzima.

  9. Jaume Ferrer de Blanes i Les sentències catòliques del diví poeta Dant. Una mostra de la presència de Dant al renaixement català

    Directory of Open Access Journals (Sweden)

    Josep Llorenç i Blat

    2014-12-01

    Full Text Available Procurador reial i nobiliari, cosmògraf, joier, lapidari, mercader i escriptor, i al capdavall, un ciutadà català honrat, Ferrer (Vidreres, ~1445 – Blanes, 1529 va marxar de ben jove a la cort de Nàpols, al servei del rei Ferran i. Acabada aquesta peripècia italiana va tornar a Blanes al servei del vescomte de Cabrera i de Bas fins que va morir a la mateixa vila al 1529. Un seu criat, disset anys més tard, va editar uns papers esparsos que havia trobat a can Ferrer, les Sentèncias cathòlicas del diví poeta Dant florentí, compilades per lo prudentíssim mossèn Jaume Ferrer de Blanes, que constiueixen un exemple de la presència de Dant al renaixement català. Lord Ferrer (Vidreres,~1445 – Blanes,1529, royal and aristocratic attorney, cosmographer, jewelrer, lapidary, merchant and writer, after all, an honorable Catalan citizen, left early age, at the court of Naples at King Ferdinand’s i service. After this eventful Italian journey he went back to Blanes at the Viscount of Cabrera and Bas’ service, until he died in the same town in 1529. One of his servants, seventeen years later, published some of the documents which were found scattered in Ferrer’s House, Catholic sentences from the divine poet Dante Florentine, compiled by most respectable lord Jaume Ferrer de Blanes, an exemple of the presence of Dante in Catalan Renaissance.

  10. Synthesis and catalytic properties of iron - cerium phosphates with surfactant Síntese e propriedades catalíticas de ferro-fosfato de cério com surfactante

    Directory of Open Access Journals (Sweden)

    H. Onoda

    2013-03-01

    Full Text Available Iron phosphate was prepared from iron nitrate and phosphoric acid with a surfactant, pentaethylene glycol mono dodecyl ether. The chemical composition of the obtained samples was estimated from ICP and XRD measurements. Particle shape and size distribution were observed by SEM images and laser diffraction / scattering methods. Further, the catalytic activity was studied with the decomposition of the complex between formaldehyde, ammonium acetate, and acetylacetone. The peaks of FePO4 were observed in XRD patterns of samples prepared in Fe/Ce=10/0 and then heated at 600 ºC. Other samples were amorphous in XRD patterns. Iron-cerium phosphates had high catalytic activity for the decomposition of the complex.Fosfato de ferro foi preparado a partir do nitrato de ferro e ácido fosfórico com um surfactante éter monododecil pentaetileno glicol. A composição química das amostras obtidas foi estimada a partir de medidas por ICP e DRX. A distribuição e forma das partículas foram observadas por imagens de MEV e o pelo método de espalhamento de laser. A atividade catalítica foi estudada com a decomposição do complexo entre formaldeido, acetato de amônio e acetilacetona. Os picos de FePO4 foram observados nos padrões de DRX das amostras preparadas Fe/Ce=10/0 e então aquecidas a 600 ºC. Outras amostras foram de padrões de DRX amorfo. Ferro-fosfatos de cério tiveram alta atividade catalítica para a decomposição do complexo.

  11. La expresión y actividad catalítica diferencial de GDP-manosa pirofosforilasa influye en la producción de vitamina C en Myrciaria dubia “camu-camu”

    Directory of Open Access Journals (Sweden)

    Juan Castro Gómez

    2013-12-01

    Full Text Available Myrciaria dubia muestra una amplia variación en la producción de vitamina C (vit.C. Para entender las bases moleculares de esta variación, se determinó la relación del nivel de expresión genética y actividad de GDP-Manosa pirofosforilasa (GMP con la variación del contenido de vit.C en M. dubia. Las muestras fueron obtenidas de una colección de germoplasma. La vit.C se cuantificó por HPLC, la actividad de GMP se midió por espectrofotometría. El ARN se purificó, el ADNc se sintetizó, amplificó, clonó y secuenció con técnicas estándares. La expresión del gen se midió mediante PCR en tiempo real. Las diferencias en el contenido de vit.C de las hojas, pulpa y cáscara dependieron de la expresión y actividad de GMP. Esta relación también se observó entre plantas que producen frutos con bajo y alto contenido de vit.C. En conclusión, Las hojas, pulpa y cáscara de M. dubia muestran diferencias significativas en el contenido de vit.C, el cual se atribuye a la expresión y actividad catalítica diferencial de la GMP. Asimismo, las plantas que producen frutos con diferencias marcadas en el contenido de vit. C en sus pulpas, también dependen del nivel de expresión y actividad catalítica de esta enzima.

  12. Three luminescent d{sup 10} metal coordination polymers assembled from a semirigid V-shaped ligand with high selective detecting of Cu{sup 2+} ion and nitrobenzene

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Wei-Ping [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, Shaanxi Key Laboratory of Physico-Inorg. Chem., College of Chemistry & Materials Science, Northwest University, Xi’an 710069 (China); Institute of Functional Materials, College of Chemistry and Pharmaceutical Engineering, Sichuan University of Science & Engineering, Zigong 643000 (China); Liu, Ping; Liang, Yu-Tong; Cui, Lin; Xi, Zheng-Ping [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, Shaanxi Key Laboratory of Physico-Inorg. Chem., College of Chemistry & Materials Science, Northwest University, Xi’an 710069 (China); Wang, Yao-Yu, E-mail: wyaoyu@nwu.edu.cn [Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, Shaanxi Key Laboratory of Physico-Inorg. Chem., College of Chemistry & Materials Science, Northwest University, Xi’an 710069 (China)

    2015-08-15

    Three 2D luminescent coordination polymers with helical frameworks, [ZnL{sub 2}]{sub n} (1) and ([ML{sub 2}]·(H{sub 2}O)){sub n} (M=Zn (2), Cd (3)) (HL=4-((2-methyl-1 H-imidazol-1-yl)methyl)benzoic acid), have been assembled under hydro(solvo)thermal conditions. Complex 1 is in chiral space group and displays a rare 2D→2D 2-fold parallel interpenetrated layer network with two types of chiral double helixes. Interestingly, the single crystal structure analyses indicate the coexistence of enantiomers la and 1b in one pot, while the bulk crystallization of 1 are racemic mixtures based on the CD measurement. 2 and 3 are isostructural, in the structure, there are two kinds of 2D chiral helical-layers which stack in an -ABAB- sequence leading to the overall structure are mesomer and achiral. All compounds display intense luminescence in solid state at room temperature with high chemical and thermal stability. More importantly, 1 has been successfully applied in the detection of Cu{sup 2+} ions in aqueous media and nitrobenzene and the probable detecting mechanism was also discussed. - Graphical abstract: Three luminescent d{sup 10} metal coordination polymers with helical-layer based on 4-((2-methyl-1H-imidazol-1-yl)methyl)benzoic acid have been obtained. Compound 1 shows high selective detecting for Cu{sup 2+} ion in aqueous and nitrobenzene. - Highlights: • Three coordination polymers with chiral helical-layer have been obtained. • 1 Can luminescent detect Cu{sup 2+} ion in aqueous media and nitrobenzene. • Racemic mixture or mesomer compounds can be obtained by controlling the reaction conditions.

  13. Sorption of Nitrobenzene to Anionic Surfactant Modified Layered Double Hydroxides%阴离子表面活性剂改性水滑石吸附硝基苯的特性研究

    Institute of Scientific and Technical Information of China (English)

    夏燕; 朱润良; 陶奇; 刘汉阳

    2013-01-01

    以阴离子表面活性剂十二烷基硫酸钠(sodium dodecyl sulfate,SDS)为改性剂,采用共沉淀法在不同表面活性剂浓度,0.5 ~2.0理论阴离子交换容量(theoretical anion exchange capacity,TAEC)条件下制备了有机水滑石LDH-DS,并用XRD、FT-IR表征了样品的结构特征.结果表明十二烷基硫酸根成功插层进入LDH层间,d003底面间距由0.80 nm增大至3.98 nm.同时研究了LDH-DS对硝基苯的吸附性能,表明有机水滑石对硝基苯的等温吸附曲线符合线型方程(R2>0.99),吸附过程主要为分配作用.随着样品中SDS负载量的增加,LDH-DS对硝基苯的吸附系数Kd相应增强,但有机碳标化的吸附系数Koc值基本保持恒定.吸附热力学实验显示吸附过程为吸热反应,熵增大是吸附过程的驱动力.%Sodium dodecyl sulfate (SDS) modified MgAl layered double hydroxides (LDHs) were synthesized at different surfactant concentrations (0.5-2.0 TAEC) by the co-precipitation method. The LDH-DS samples obtained were characterized by powder X-ray diffraction and FT-IR spectroscopy. The results showed that SDS was successfully intercalated into the interlayer of the LDH , and the basal spacing was expanded from 0. 80 nm to 3. 98 nm. The intercalated SDS was considered consistent with a paraffin bilayers arrangement. The sorption of nitrobenzene on LDH-DS was examined, and the results showed that linear model could fit the sorption isotherms well (R2 >0. 99) , which implied a partitioning sorption process. The sorption coefficient of nitrobenzene (Kd) on LDH-DS was positively related to the DS loading amount, but the organic carbon content normalized sorption coefficient of nitrobenzene (Koo) was shown to remain relatively constant. The sorption thermodynamics results showed that the sorption of nitrobenzene on LDH-DS was an endothermic process, and the increase of entropy was the driving force for the sorption process.

  14. Heat-induced structural changes in the lichrosorb RP-18—water high-performance liquid chromatographic system and their impact on the thermodynamic adsorption data of benzene, nitrobenzene and phenol

    OpenAIRE

    Hammers, W.E.; Verschoor, P.B.A.

    1983-01-01

    Capacity ratio (K) data of benzene, nitrobenzene and phenol have been measured on liChrosorb RP-18 with water as the eluent at temperatures between 5 and 85°C. The influence of temperature on the structure of the RP-18 layer is discussed. Partial molar free energies, entropies, enthalpies and heat capacities of adsorption have been computed as a function of temperature by fitting Taylor's series expansions to the ln k data. These thermodynamic data appear to depend on (alterations of) the str...

  15. Removal of organic micro-pollutants (phenol, aniline and nitrobenzene) via forward osmosis (FO) process: Evaluation of FO as an alternative method to reverse osmosis (RO).

    Science.gov (United States)

    Cui, Yue; Liu, Xiang-Yang; Chung, Tai-Shung; Weber, Martin; Staudt, Claudia; Maletzko, Christian

    2016-03-15

    In this study, we have explored and compared the effectiveness of using (1) lab-fabricated forward osmosis (FO) membranes under both FO and reverse osmosis (RO) modes and (2) commercially available RO membranes under the RO mode for the removal of organic micro-pollutants. The lab-fabricated FO membranes are thin film composite (TFC) membranes consisting of a polyamide layer and a porous substrate cast from three different materials; namely, Matrimid, polyethersulfone (PESU) and sulfonated polyphenylene sulfone (sPPSU). The results show that the FO mode is superior to the RO mode in the removal of phenol, aniline and nitrobenzene from wastewater. The rejections of all three TFC membranes to all the three organic micro-pollutants under the FO processes are higher than 72% and can be even higher than 90% for aniline when a 1000 ppm aromatic aqueous solution and 1 M NaCl are employed as feeds. These performances outperform the results obtained from themselves and commercially available RO membranes under the RO mode. In addition, the rejection can be maintained even when treating a more concentrated feed solution (2000 ppm). The removal performance can be further enhanced by using a more concentrated draw solution (2 M). The water flux is almost doubled, and the rejection increment can reach up to 17%. Moreover, it was observed that annealing as a post-treatment would help compact the membrane selective layer and further enhance the separating efficiency. The obtained organic micro-pollutant rejections and water fluxes under various feasible operating conditions indicate that the FO process has potential to be a viable treatment for wastewater containing organic micro-pollutants.

  16. Removal of organic micro-pollutants (phenol, aniline and nitrobenzene) via forward osmosis (FO) process: Evaluation of FO as an alternative method to reverse osmosis (RO)

    KAUST Repository

    Cui, Yue

    2016-01-05

    In this study, we have explored and compared the effectiveness of using (1) lab-fabricated forward osmosis (FO) membranes under both FO and reverse osmosis (RO) modes and (2) commercially available RO membranes under the RO mode for the removal of organic micro-pollutants. The lab-fabricated FO membranes are thin film composite (TFC) membranes consisting of a polyamide layer and a porous substrate cast from three different materials; namely, Matrimid, polyethersulfone (PESU) and sulfonated polyphenylene sulfone (sPPSU). The results show that the FO mode is superior to the RO mode in the removal of phenol, aniline and nitrobenzene from wastewater. The rejections of all three TFC membranes to all the three organic micro-pollutants under the FO processes are higher than 72% and can be even higher than 90% for aniline when a 1000 ppm aromatic aqueous solution and 1 M NaCl are employed as feeds. These performances outperform the results obtained from themselves and commercially available RO membranes under the RO mode. In addition, the rejection can be maintained even when treating a more concentrated feed solution (2000 ppm). The removal performance can be further enhanced by using a more concentrated draw solution (2 M). The water flux is almost doubled, and the rejection increment can reach up to 17%. Moreover, it was observed that annealing as a post-treatment would help compact the membrane selective layer and further enhance the separating efficiency. The obtained organic micro-pollutant rejections and water fluxes under various feasible operating conditions indicate that the FO process has potential to be a viable treatment for wastewater containing organic micro-pollutants.

  17. Movimiento social, proceso político y Mass media: el movimiento pacifista catalán ante los conflictos de Kosovo y Chechenia Movimiento social, proceso político y Mass media: el movimiento pacifista catalán ante los conflictos de Kosovo y Chechenia

    Directory of Open Access Journals (Sweden)

    Javier Alcalde Villacampa

    2004-01-01

    Full Text Available Can the level of protest be augmented considerably due to media coverage of a conflict? Though a theoretical framework based on the interaction between social movements, political process and the media, the paper compares the response of (he Catalan pacifist movement to two international conflicts: the war in Chechnya and the war in Kosovo. In the case of the Balkans, participation of the NATO will be a determinant, dividing the protest against that conflict into two different processes. In this study, the key independent variable is the media coverage that impacts on the political opportunity structure. Finally, I present hypothesis about the different strength of two Spanish social movements, that of Barcelona and in Madrid, related to the nationalistic question in Catalonia as a factor of politization.¿Puede incrementarse notablemente el nivel de protesta de un movimiento social a causa de la cobertura mediática de un conflicto? A partir de un marco teórico relativo a la interacción entre los movimientos sociales, el proceso político y los medios de comunicación el estudio analiza comparativamente la respuesta del movimiento pacifista catalán a dos conflictos internacionales: la guerra de Chechenia y la guerra de Kosovo. En el caso de los Balcanes, resulta determinante la participación de la OTAN, que subdivide el mismo en dos procesos distintos. En todos ellos, la principal variable independiente es la cobertura informativa realizada por la prensa escrita, la cual conforma uno de los factores que afectan a la estructura de oportunidad política. Los resultados sugieren que la existencia de movilización social solamente ocurrirá cuando participe la sociedad no organizada. jugando un papel esencial los medios de comunicación. Por último, esbozo algunas hipótesis a propósito de la distinta fuerza de los movimientos sociales en Madrid y en Barcelona, relacionadas con la cuestión nacional de Cataluña como factor de politización.

  18. Entonación de las oraciones interrogativas absolutas neutras en el catalán mallorquín. Comparación con el catalán central de Barcelona. (Intonation in information-seeking yes-no questions of Catalan from Majorca. Comparison with the central Catalan of Barcelona.

    Directory of Open Access Journals (Sweden)

    Sabela Labraña Barrero

    2013-12-01

    Full Text Available El presente trabajo tiene como objetivo la descripción de la entonación de frases interrogativas absolutas neutras. Dentro del marco del proyecto internacional AMPER (Atlas Multimedia de la Prosodia del Espacio Románico, se realiza el análisis acústico de las oraciones interrogativas absolutas neutras sin “que” de la variación mallorquina del catalán. Las oraciones son de tres tipos: SVO, SEVO (en las que E es la expansión de sujeto, y SVOE (en las que E es la expansión de objeto. Se analizan los valores de la F0, la intensidad y la duración de las vocales de las frases. La comparación de las realizaciones de las mismas oraciones para el dialecto de Barcelona (Fernández Planas y otros, 2004; Szmidt y otros, 2008 revela ciertas diferencias en la línea melódica en las dos variedades dialectales. Con respecto a la duración y la intensidad, tanto el mallorquín como el barcelonés muestran las mismas características en todos los tipos de oraciones comparados: la duración más larga en el último acento tonal y la intensidad más elevada en el pretonema, acompañada de una disminución en el último acento tonal de la frase. (Our aim in this paper is the description of the intonation of information-seeking yes-no questions. Within the framework of the AMPER project (Atlas Multimedia de la Prosodia del Espacio Románico, we analysed acoustically the information-seeking yes-no questions in the Majorcan variety of Catalan. Three types of sentence structures were analysed: SVO, SEVO (where E stands for expanded subject, SVOE (where E stands for expanded object structures. We analyse the values of F0, intensity and duration of the vowels. As for as the melodic line is concerned, our analysis revealed the existence of different intonational contours in Majorcan Catalan, which are different from those described for Barcelona dialect (Fernández Planas y otros, 2004; Szmidt y otros, 2008. In respect of the duration and intensity, both

  19. Enhanced nitrobenzene removal and column longevity by coupled abiotic and biotic processes in zero-valent iron column

    DEFF Research Database (Denmark)

    Yin, Weizhao; Wu, Jinhua; Huang, Weilin;

    2015-01-01

    /or co-precipitation and the reduction of NB to aniline (AN) via abiotic reaction in the abiotic column and via both abiotic and biotic reactions in the biotic column. Due to the interactive effect of ZVI and microorganisms, more effective iron consumption and more reactive minerals such as green rust......In this study, abiotic zero-valent iron (ZVI) column and biotic ZVI column were employed to investigate abiotic and biotic effects between iron and microorganisms on NB removal and column longevity. Physical removal and kinetics analysis revealed that NB was largely removed through adsorption and...... and iron sulfide were found in the biotic column. This led to approximately 50% higher total NB removal and 6 times higher AN production in the biotic column as compared to the abiotic column during the entire operation. According to the NB breakthrough curves, longer stability and longer life...

  20. Les polítiques turístiques en el marc de la reestructuració de les destinacions litorals. Avaluació dels plans d'excel·lència turística al litoral català.

    OpenAIRE

    Beas Secall, Lorena

    2009-01-01

    En esta tesis se analiza si las políticas turísticas han servido para reorientar y revitalizar la actividad turística del litoral catalán. El trabajo se estructura en tres partes, una primera más teórica, donde se explica el marco conceptual y el punto de partida de esta investigación; una segunda en la cual se analiza el estado y la evolución de la actividad turística al litoral catalán; y la tercera donde se evalúa la figura de los planes de excelencia turística, como instrumento de polític...

  1. Les polítiques turístiques en el marc de la reestructuració de les destinacions litorals. Avaluació dels plans d'excel·lència turística al litoral català.

    OpenAIRE

    2009-01-01

    En esta tesis se analiza si las políticas turísticas han servido para reorientar y revitalizar la actividad turística del litoral catalán. El trabajo se estructura en tres partes, una primera más teórica, donde se explica el marco conceptual y el punto de partida de esta investigación; una segunda en la cual se analiza el estado y la evolución de la actividad turística al litoral catalán; y la tercera donde se evalúa la figura de los planes de excelencia turística, como instrumento de polític...

  2. Comparative Study of Catalytic Systems T iO2 and N b2O5 Estudio catalítico comparativo de los sistemas TiO2 y Nb2O5 en la degradación de cianuro en función del tipo de oxidante

    Directory of Open Access Journals (Sweden)

    Aida Liliana Barbosa López

    2012-12-01

    Full Text Available This article discusses the viability of using agents such as niobium photocatalyst in decreasing higher energy of the band gap. To do so competitively withT iO2, the presence of oxidation helpers such as H2O2 and O3 could presentsurprising results in the catalytic performance due to higher generation ofOH o radicals. Oxidation helpers are shown to assist in obtaining larger areaoxides and textural properties different from commercial niobium oxide, andenhancing its catalytic activity in free cyanide removing. The article presentsexperimental results of cyanide photodegradation of 100mg/l with Degussa P-25 T iO2 and Nb2O53H2O, using a type CPC photoreactor and sunlight as theradiation source. Taking an inclination equal to Cartagena latitude of 10,450,the results show a clear effect of pH, catalyst type and oxidation auxiliar agenton photodegradation reaction. The ion cyanide reduction of polluted effluentwas enhanced by oxidizing agent (O3 and H2O2 addition. This may suggesta greater susceptibility to free cyanide oxidation and cianate indirect oxidation due to higher hydroxyl radical generation, which was induced by H2O2or O3 presence under solar radiation. The results showed free cyanide photocatalytic oxidation percentages between 64% and 72% using Nb2O5 3H2Oand 67% and 71% using T iO2 Degussa P-25. The catalysts were characterizedstructurally by XRD, BET, Raman and FTIR, with the purpose of correlatingmorphological changes in catalytic performing.La viabilidad del uso de otros agentes fotocatalizadores como el niobio, radicaen disminuir las energías altas de la banda prohibida para hacerlo competitivofrente al TiO2, sin embargo la presencia de coayudantes de oxidación, talescomo H2O2 y O3 podrían presentar resultados sorprendentes en el desempeñocatalítico, debido a una mayor generación del radicales OH. La obtención deóxidos de mayor área y propiedades texturales diferentes al oxido de niobiocomercial, mejoran su actividad catal

  3. Models de traducció literària i audiovisual en català col·loquial: el cas de «Jackie Brown» de Quentin Tarantino

    Directory of Open Access Journals (Sweden)

    Dídac Pujol

    2015-10-01

    Full Text Available Resum: Aquest article tracta dels models de traducció col·loquial cap al català en el cas de la versió doblada (1997, la versió subtitulada (1997 i el guió traduït (1998 de Jackie Brown (1997 de Quentin Tarantino. El nucli de l’article és l’anàlisi i la comparació de la fonètica, la morfologia, la sintaxi i el lèxic de cada traducció catalana, que s’emmarca en els models lingüístics i de traducció vigents en el període objecte d’estudi. La conclusió a la qual s’arriba és que les tres traduccions utilitzen models de llengua col·loquial diferents. El guió traduït basteix un model trencador, sobretot en qüestions de representació fonètica i en el lèxic castellà que utilitza. La versió doblada s’adequa als criteris de traducció i doblatge de TV3: d’una banda, presenta una sintaxi relativament col·loquial (menys col·loquial que la de la versió subtitulada, però no tant com la del guió traduït; i, d’altra banda, fa ús d’una morfologia estàndard que explota poc els recursos col·loquials de la llengua meta. La versió subtitulada s’acosta més a la parla col·loquial que la versió doblada, sobretot en qüestions de lèxic, àmbit en el qual utilitza molts menys castellanismes que el guió traduït.Paraules clau: traducció literària, traducció audiovisual, doblatge, subtitulació, català col·loquial, models de traducció col·loquial, Quentin Tarantino, Jackie Brown.

  4. Insights into the late-stage differentiation processes of the Catalão I carbonatite complex in Brazil: New Sr-Nd and C-O isotopic data in minerals from niobium ores

    Science.gov (United States)

    Oliveira, Ítalo L.; Brod, José A.; Cordeiro, Pedro F. O.; Dantas, Elton L.; Mancini, Luis H.

    2017-03-01

    The Late Cretaceous Catalão I carbonatite complex consists of ultramafic silicate rocks, phoscorites, nelsonites and carbonatites. The latest stages of the evolution of the complex are characterized by several nelsonite (magnetite-apatite rock) and carbonatite dykes, plugs and veins crosscutting earlier alkaline rocks. The interaction between the latter and late-stage carbonatites and/or carbo-hydrothermal fluids, converted the original dunites and bebedourites to metasomatic phlogopitites. Late-stage nelsonites (N1), pseudonelsonites (N2) and various types of dolomite carbonatites (DC) including norsethite-, magnesite- and/or monazite-bearing varieties show significant whole-rock Nd and Sr isotopic variations. To elucidate whether magmatic or metasomatic processes, or both, were responsible for these isotope variations we characterized the Nd and Sr isotope compositions of major mineral phases (i.e. apatite, dolomite, norsethite, pyrochlore and tetraferriphlogopite) in these late-stage rocks. Mineral isotope data recorded the same differences observed between N1 and N2 whole-rocks with N2 minerals showing more enriched isotopic signatures than minerals from N1. Sr isotopic disequilibrium among minerals from N2 pseudonelsonites and spatially related dolomite carbonatite pockets implies formation from batches of carbonate melts with distinct isotopic compositions. A detailed investigation of Nd and Sr isotopes from whole-rocks and minerals suggests that the most evolved rocks of the Catalão I complex probably derive from two different evolution paths. We propose that an earlier magmatic trend (path A) could be explained by several batches of immiscible and/or residual melts derived from carbonated-silicate parental magma (e.g. phlogopite picrite) contaminated with continental crust to a variable extent, in an AFCLI-like process. A second trend (path B) comprises highly variable 143Nd/144Ndi at nearly constant 87Sr/86Sri coupled with high δ18O in carbonates. This

  5. Avaliação das condições de envelhecimento do sistema catalítico versatato de neodímio/hidreto de di-isobutilalumínio/cloreto de t-butila na polimerização de 1,3-butadieno

    Directory of Open Access Journals (Sweden)

    Neusa Maria Tocchetto Pires

    2014-01-01

    Full Text Available O objetivo deste trabalho foi estudar sistemas catalíticos ternários constituídos por versatato de neodímio, cloreto de t-butila e hidreto de di-isobutil-alumínio para a polimerização de 1,4-cis de butadieno em hexano. Foi investigado o efeito do envelhecimento natural do catalisador (1 a 60 dias a 8,5°C sobre a conversão, a atividade catalítica e a micro- e macroestrutura do polibutadieno. Foi estudado também o efeito do envelhecimento forçado (40°C, das diferentes fases do preparo do catalisador sobre as características da polimerização e do polímero sintetizado. Os polímeros foram caracterizados por cromatografia de exclusão por tamanho (SEC, espectroscopia na região do infravermelho (FT-IR, viscosimetria em solução e no estado fundido. O envelhecimento forçado das diferentes fases do catalisador (F1, F2, F3 e F4 afetou a conversão e a atividade catalítica de maneiras distintas. Os resultados de conversão e atividade catalítica mostraram que a fase mais afetada pelo envelhecimento forçado a 40°C foi a F1, etapa em que o versatato de neodímio é adicionado à solução de hidreto de di-isobutil-alumínio (Catalisador 447. A microestrutura não se alterou com o envelhecimento natural do catalisador enquanto que a macroestrutura mostrou dependência desta variável. Foi observado um ligeiro aumento na conversão e na atividade catalítica à medida que o tempo de envelhecimento do catalisador aumentou de 1 para 10 dias.

  6. Reforma catalítica do metano sobre 1,5%Ni/α-Al2O3 dopado com elementos metálicos diferentes Catalytic reforming of methane over 1.5%Ni/α-Al2O3 doped with different metallic elements

    Directory of Open Access Journals (Sweden)

    L. S. Neiva

    2012-06-01

    Full Text Available O objetivo deste trabalho é desenvolver catalisadores de Ni suportados em α-Al2O3 dopada com os seguintes elementos metálicos: ferro, zinco, cério e zircônio. Os suportes catalíticos de α-Al2O3 dopada foram obtidos por meio do método de síntese da reação de combustão e o níquel, na condição de espécie ativa catalítica, foi depositado sobre os suportes por meio do método de impregnação úmida. As caracterizações estruturais, bem como, a avaliação dos desempenhos catalíticos destes materiais cerâmicos na reação de reforma a vapor do metano fazem parte dos objetivos deste trabalho. Os suportes catalíticos sintetizados apresentaram estruturas cristalinas com dimensão de suas porosidades na faixa da microporosidade associada à presença de mesoporos. A avaliação catalítica das amostras obtidas neste trabalho, na reação de reforma a vapor do metano, revelou que o desempenho catalítico deste tipo de material é influenciado por suas características físicas, tais como, valor da área superficial das partículas que compõem a estrutura, como também, o valor médio dos diâmetros de poros da mesma. Dentre as quatro amostras desenvolvidas neste trabalho, a amostra de α-Al2O3 dopada com zinco contendo 1,5% de Ni como espécie ativa catalítica, apresentou valores percentuais de conversão do metano mais elevados que as demais amostras.The aim this work is to develop Ni catalysts supported on α-Al2O3 doped with the following metallic elements: iron, zinc, cerium and zirconium. The catalytic supports composed by α-Al2O3 doped were obtained by means method of synthesis of the combustion reaction and the nickel in the active catalytic species condition, was deposited over the supports by the method of wet impregnation. The structural characterizations, as well as the evaluation of performance of these ceramic materials in catalytic reaction of steam reforming of methane are among the objectives of this work. The

  7. Variação temporal dos elementos climáticos e da ETo em Catalão, Goiás, no período de 1961-2011

    Directory of Open Access Journals (Sweden)

    Leonidas P. de Alencar

    2014-08-01

    Full Text Available Neste trabalho se avaliou a existência de tendência na distribuição temporal dos elementos do clima e da evapotranspiração de referência para a localidade de Catalão, no estado de Goiás. Para o período de 1961 a 2011 um conjunto de dados diários de temperatura máxima e mínima do ar, insolação, velocidade do vento e umidade relativa, para o período de 1961 a 2011 foi utilizado para o cálculo da evapotranspiração pelo método de Penman-Monteith. Buscou-se identificar a presença de tendência para as séries de dados mensais através da aplicação dos testes estatísticos de Mann-Kendall, do estimador da inclinação de Sen e da regressão linear com o teste de Student, para o coeficiente angular da reta. Devido ao aumento das temperaturas máxima e mínima e à redução da umidade relativa, aumentos estatisticamente significativos foram observados na evapotranspiração de referência para os meses de setembro, outubro, dezembro e para a série anual.

  8. Estudio de la hidratación de pastas de cemento adicionadas con catalizador de craqueo catalítico usado (FCC de una refinería colombiana

    Directory of Open Access Journals (Sweden)

    Jenny Johanna Trochez

    2010-01-01

    Full Text Available En este artículo se analiza el efecto de la incorporación de un residuo industrial de una refinería de petróleo colombiana, conocido como catalizador de craqueo catalítico usado (FCC, en el proceso de hidratación de pastas cementicias. Para tal efecto, se prepararon pastas de cemento Pórtland ordinario (OPC adicionadas en porcentajes del 10 y 20% de FCC como reemplazo de la cantidad de cemento. La reactividad puzolánica del material y el tipo de productos de hidratación se determinó mediante difracción de rayos X (DRX y análisis termogravimétrico (TG/DTG. Adicionalmente, se determinó el calor de hidratación liberado con base en la norma ASTM C186. Los resultados indican que el proceso de hidratación de pastas adicionadas con FCC es altamente exotérmico como consecuencia de su actividad puzolánica a cortas edades. Las fases principales presentes en el proceso de hidratación de las pastas adicionadas con FCC fueron CSH, CAH y CASH, productos similares a los obtenidos en pastas adicionadas con metacaolín.

  9. Estudio DRX en Materiales Catalizadores Cu-Ni-SiO2 para Hidrogenación de aceite de soya. Desarrollo de estructura cristalina y actividad catalítica

    Directory of Open Access Journals (Sweden)

    Gloria I. Cubillos

    2009-01-01

    Full Text Available Para buscar elementos experimentales que soporten la hipótesis según la cual se forman estructuras cristalinas Cu-Ni o eventualmente Cu-Ni-SiO2 en la síntesis de catalizadores para la hidrogenación de aceite de soya, se prepararon mezclas de estos tres materiales a partir de sales de los metales con sílice (aerosil. Se calcinaron a 270oC y se redujeron a 330oC en atmósfera de hidrógeno. En  los materiales reducidos se  estudió el difractógrama de RX en el rango 37 a 53 grados, y se comparó con el difractógrama de aleaciones Cu-Ni, en las cuales se conoce la formación  de cristales mixtos, y  con los difractógramas de los elementos puros Cu y Ni.  Los resultados muestran que se presentan señales de difracción diferentes a las señales de los componentes puros. La actividad catalítica se muestra diferente en los materiales que presentan distorsión en su estructura cristalina.  

  10. La patrimonialización de la memoria histórica: entre el deber social y la estrategia turística. Apuntes sobre el caso catalán.

    Directory of Open Access Journals (Sweden)

    David González Vázquez

    2016-01-01

    Full Text Available El año 2014 se ha cumplido el trigésimo aniversario de la teorización de los “lieux de mémoire” por parte del historiador francés Pierre Nora. A lo largo de este tiempo, se ha consolidado en Europa un modelo de puesta en valor patrimonial para los lugares de memoria, ligados, sobretodo, a las guerras mundiales y el Holocausto. Francia ha sido, con la entrada del nuevo siglo, quien ha desarrollado un modelo teórico que relaciona dicho patrimonio memorial con la práctica turística. No es casualidad, pues ha surgido fruto del bagaje práctico de numerosos años de experiencia, lo que reafirma a su modelo de “tourisme de mémoire”como la referencia a nivel mundial. España, a causa de un retraso sociopolítico de décadas con respecto a sus homónimos occidentales, no ha comenzado hasta estos últimos años a reivindicar sus espacios de memoria, relacionados con la memoria histórica de la Guerra Civil y la Dictadura. El caso catalán, pionero en cuanto a la implementación de una estrategia turística, ha sentado las bases de un modelo emergente.

  11. Uso de test de lixiviación para determinar la migración de contaminantes en morteros de sustitución con residuos de catalizador de craqueo catalítico (FCC

    Directory of Open Access Journals (Sweden)

    Carolina Martínez-López

    2013-01-01

    Full Text Available En este estudio se evalúa la viabilidad ambiental en la utilización de dos residuos de catalizador de craqueo catalítico procedentes de fuentes diferentes (Colombia y España, como sustitución parcial del cemento Portland, para la fabricación de materiales de construcción. Inicialmente se realizó la caracterización de los materiales analizando la composición química, la distribución del tamaño de partícula y la morfología. Posteriormente, para determinar las características tóxicas de lixiviación, se aplicaron las técnicas de SPLP (Synthetic Precipitation Leaching Procedure y NEN 7341 de la normativa holandesa, en morteros sustituidos con un 20% de FCC con respecto a la cantidad de cemento. Los resultados indican que las concentraciones de los metales pesados lixiviados son muy bajas comparadas con lo establecido por la legislación ambiental. Debido a esto, se considera que el residuo en las proporciones estudiadas no constituye un problema ambiental, proponiéndose como un material alternativo para el sector de la construcción.

  12. Dinuclear complexes of copper and zinc with m-xylene/cyclohexane-linked bis-aspartic acids: synthesis, characterization, dioxygen activation, and catalytic oxidation of nitrobenzene in pure aqueous solution.

    Science.gov (United States)

    Zhu, Shourong; Qiu, Zhixiang; Ni, Tianjun; Zhao, Xiujuan; Yan, Shikai; Xing, Feifei; Zhao, Yongmei; Bai, Yueling; Li, Mingxing

    2013-08-14

    Two new m-xylene/cyclohexane-linked bis-aspartic acid ligands, L(b) and L(c), were synthesized via Michael addition in basic aqueous solution. Their structures were characterized by elemental analysis, NMR and MS spectrometry. Both ligands react with Cu(II) and Zn(II) to form dinuclear complexes, with M2L(OH)(-) the major species in neutral/weak basic aqueous solution. To quantify the relative interaction strength between a Lewis acid and base, a new parameter σ = log K/14 was proposed which compares the stability constant with the binding constant between H(+) and OH(-). The dinuclear copper complexes (L(b)-2Cu and L(c)-2Cu) react with H2O2 in aqueous solution. The reaction in 0.020 M phosphate buffer at pH 7.5 is first-order for [L(c)-2Cu], but second-order for [L(b)-2Cu]. The oxidation products are oxygenated and/or dehydrogenated species. Radical trapping tests indicate that both complexes slightly scavenge the OH˙ radical, but generate the H˙ radical. L(c)-2Cu generates the H˙ radical much more effectively than that of L(b)-2Cu when reacted with H2O2. Both complexes are excellent catalysts for the oxidation of nitrobenzene in the presence of H2O2 in weakly basic aqueous solution. The oxidation follows the rate-law v = k[complex][nitrobenzene][H2O2]. The k values in pH 8.0 phosphate buffer at 25 °C are 211.2 ± 0.3 and 607.9 ± 1.7 mol(-2) L(2) s(-1) for L(b)-2Cu and L(c)-2Cu, respectively. The Arrhenius activation energies are 69.4 ± 2.2 and 70.0 ± 4.3 kJ mol(-1) for L(b)-2Cu and L(c)-2Cu, respectively, while the Arrhenius pre-exponential factors are 2.62 × 10(14) and 1.06 × 10(15), respectively. The larger pre-exponential factor makes L(c)-2Cu more catalytically active than L(b)-2Cu. These complexes are some of the most effective oxidation catalysts known for the oxidation of nitrobenzene.

  13. The kinetics and QSAR of abiotic reduction of mononitro aromatic compounds catalyzed by activated carbon.

    Science.gov (United States)

    Gong, Wenwen; Liu, Xinhui; Gao, Ding; Yu, Yanjun; Fu, Wenjun; Cheng, Dengmiao; Cui, Baoshan; Bai, Junhong

    2015-01-01

    The kinetics of abiotic reduction of mono-nitro aromatic compounds (mono-NACs) catalyzed by activated carbon (AC) in an anaerobic system were examined. There were 6 types of substituent groups on nitrobenzene, including methyl, chlorine, amino, carboxyl, hydroxyl and cyanogen groups, at the ortho, meta or para positions. Our results showed that reduction followed pseudo-first order reaction kinetics, and that the rate constant (logkSA) varied widely, ranging between -4.77 and -2.82, depending upon the type and position of the substituent. A quantitative structure-activity relationship (QSAR) model using 15 theoretical molecular descriptors and partial-least-squares (PLS) regression was developed for the reduction rates of mono-NACs catalyzed by AC. The cross-validated regression coefficient (Qcum(2), 0.861) and correlation coefficient (R(2), 0.898) indicated significantly high robustness of the model. The VIP (variable importance in the projection) values of energy of the lowest unoccupied molecular orbital (ELUMO) and the maximum net atomic charge on the aromatic carbon bound to the nitro group (QC(-)) were 1.15 and 1.01, respectively. These values indicated that the molecular orbital energies and the atomic net charges might play important roles in the reduction of mono-NACs catalyzed by AC in anaerobic systems.

  14. Zn3-MOF as highly efficient fluorescent sensor for nitrobenzene%Zn3-MOF用于硝基苯的高效荧光识别

    Institute of Scientific and Technical Information of China (English)

    赵旭东; 张玉田; 黄宏亮; 刘大欢; 仲崇立

    2015-01-01

    硝基苯(nitrobenzene,NB)可以对水体、土壤等生态系统及人体健康造成严重的危害。为了有效地识别和检测硝基苯,制备了一种微孔的荧光金属-有机骨架材料(metal-organic framework,MOF),Zn3-MOF。通过反应物浓度及比例的调节,反应时间相对于前人工作缩短了一半。该材料在一系列常见有机小分子中的荧光响应结果表明,硝基苯对 Zn3-MOF 具有高效的荧光淬灭能力。进一步的系统研究发现,Zn3-MOF 对硝基苯的浓度检测下限可低至10 mg·L−1,同时具有良好的再生能力。硝基苯对该MOF的荧光淬灭源自其与MOF骨架的π-π作用以及MOF配体向硝基苯的电子转移。这些结果表明Zn3-MOF是一种高选择性、高灵敏度的硝基苯荧光探针。%Nitrobenzene (NB) can seriously damage the ecosystems of water and soil as well as human health. To detect NB efficiently, a microporous luminescent metal-organic framework (MOF) with mixed ligands, Zn3-MOF, was synthesized by a solvothermal method. Compared to the reported works, the reaction time was reduced by modifying the solution concentration and ratio of reactants. The microporous structure resulting from interpenetration can be beneficial in sensing small organic molecules. Thus, the fluorescent response to commonly used organic small molecules was studied in this work. The results indicate that Zn3-MOF is highly selective towards nitrobenzene and the fluorescence quenching for NB can be visible with the naked eyes at UV=365 nm. The fluorescence intensity decreases with the increasing concentration of NB and the detection limit can reach up to 10 mg·L−1. Moreover, this MOF also shows excellent regeneration ability. Fluorescence quenching for NB may be derived fromπ-π reactionbetween the framework and NB as well as the electron transfer from the electron-donating framework to the electron-withdrawing group (NO2) in NB. These results indicate that Zn3

  15. Protein engineering of toluene-o-xylene monooxygenase from Pseudomonas stutzeri OX1 for oxidizing nitrobenzene to 3-nitrocatechol, 4-nitrocatechol, and nitrohydroquinone.

    Science.gov (United States)

    Vardar, Gönül; Ryu, Kang; Wood, Thomas K

    2005-01-26

    Toluene-o-xylene monooxygenase (ToMO) from Pseudomonas stutzeri OX1 was found to oxidize nitrobenzene (NB) to form m-nitrophenol (m-NP, 72%) and p-NP (28%) with an initial rate of 0.098 and 0.031 nmol/(min mg protein), respectively. It was also discovered that wild-type ToMO forms 4-nitrocatechol (4-NC) from m-NP and p-NP with an initial rate of 0.15 and 0.0082 nmol/(min mg protein), respectively, and 3-NC (12%) and nitrohydroquinone (NHQ, 88%) from o-NP with an initial rate of 0.11 and 0.8 nmol/(min mg protein), respectively. To increase the oxidation rate and alter the oxidation regiospecificity of nitro aromatics as well as to study the role of the active site residues I100, Q141, T201, and F205 of the alpha hydroxylase fragment of ToMO (TouA), DNA shuffling and saturation mutagenesis were used to generate random mutants. The mutants were initially identified by screening via a rapid agar plate assay and then were further examined by high-performance liquid chromatography (HPLC) and gas chromatography (GC). Several mutants with higher rates of activities and with different regiospecificities were identified; for example, Escherichia coli TG1 cells expressing either TouA mutant M180T/E284G or E214G/D312N/M399V produce 4-NC 4.5- and 20-fold faster than wild-type ToMO (0.037 and 0.16 nmol/min mg protein from p-NP, respectively). TouA mutant A107T/E214A had the regiospecificity of NB changed significantly from 28% to 79% p-NP. From 200 microM NB, TouA variants A101T/M114T, A110T/E392D, M180T/E284G, and E214G/D312N/M399V produce 4-NC whereas wild-type ToMO does not. From m-NP, TouA mutant I100Q produces 4-NC (37%) and NHQ (63%), whereas wild-type ToMO produces only 4-NC (100%). Variant A107T/E214A acts like a para enzyme and forms p-cresol as the major product (93%) from toluene with enhanced activity (2.3-fold), whereas wild-type ToMO forms 32%, 21%, and 47% of o-, m-, and p-cresol, respectively. Hence, the non-specific ToMO was converted into a regiospecific enzyme

  16. Catalytic performance of Fe3O4-CoO/Al2O3 catalyst in ozonation of 2-(2,4-dichlorophenoxy) propionic acid,nitrobenzene and oxalic acid in water

    Institute of Scientific and Technical Information of China (English)

    Shaoping Tong; Rui Shi; Hua Zhang; Chunan Ma

    2010-01-01

    the precursors,and its catalytic performance was investigated in ozonation of 2-(2,4-dichlorophenoxy) propionic acid (2,4-DP),nitrobenzene and oxalic acid.The experimental results indicated that Fe3O4-CoO/Al2O3 catalyst enabled an interesting improvement of ozonation efficiency during the degradation of each organic pollutant,and the Fe3O4-CoO/Al2O3 catalytic ozonation system followed a radical-type mechanism.The kinetics of ozonation alone and Fe3O4-CoO/Al2O3 catalytic ozonation of three organic pollutants in aqueous solution were discussed under the mere consideration of direct ozone reaction and OH radical reaction to well investigate its performance.In the catalytic ozonation of 2,4-DP,the apparent reaction rate constants (k) were determined to be 1.456×10-2 min-1 for ozonation alone and 4.740×10-2 min-1 for O3/Fe3O4-CoO/Al2O3.And O3/Fe3O4-CoO/Al2O3 had a larger Rct (6.614×10-9) calculated by the relative method than O3 did (1.800×10-9),showing O3/Fe3O4-CoO/Al2O3 generated more hydroxyl radical.Similar results were also obtained in the catalytic ozonation of nitrobenzene and oxalic acid.The above results demonstrated that the catalytic performance of Fe3O4-CoO/Al2O3 in ozonation of studied organic substance was universal to a certain degree.

  17. Progress on Treatment Technique of Iron-carbon Micro-electrolysis for Nitrobenzene Waste-water%铁碳微电解预处理硝基苯废水工艺研究进展

    Institute of Scientific and Technical Information of China (English)

    张维涛

    2015-01-01

    Iron-carbon micro-electrolysis is a kind of high efficient, low-cost pretreatment technology for waste-water.Reaction process includes redox, electric enrichment, physical adsorption and coagulation sedimentation.The research progress of pre-treatment of nitrobenzene waste-water was introduced, and process factors on iron-carbon micro-electrolysis pretreatment of nitrobenzene waste-water were summarized and analyzed.The optimal pH value was between 2~3, the iron/carbon mass ratio was between (2:1)~(1:1), iron type was industrial scrap iron, dissolved oxygen had inhibitory effect, and the reaction mechanism was introduced.The future research of iron-carbon micro-electrolysis was prospected.%铁碳微电解是一种高效、廉价的废水预处理技术,反应过程主要包括氧化还原、电富集、物理吸附和混凝沉降等。本文介绍了其预处理硝基苯废水的研究进展,对铁碳微电解预处理硝基苯废水的工艺影响因素进行了总结和分析,得出最适宜pH值为2~3之间,铁/碳剂质量比为(2:1)~(1:1)之间,铁类型为工业废铁,溶解氧具有抑制作用;并对对反应机理研究进行介绍。最后对铁碳微电解技术未来研究重点作了展望。

  18. 微反应器内硝基苯气-液-固三相催化加氢反应%Gas-Liquid-Solid Three-Phase Catalytic Hydrogenation of Nitrobenzene in a Microreactor

    Institute of Scientific and Technical Information of China (English)

    胡婧婧; 赵玉潮; 李淑莲; 杨梅; 陈光文

    2011-01-01

    The influences of coating method, support and loading amount of Pd on the three-phase catalytic hydrogenation of nitrobenzene in a microchannel reactor were investigated. The results showed that the activity of catalyst prepared by coating-impregnation method was better than that of the catalyst prepared by sol-gel method, and the nitrobenzene conversion and the aniline selectivity reached 89.2% and 93.8%, respectively. The catalyst with the stronger acidity and larger specific surface area favored a higher catalytic activity. The catalyst with active component Pd 2.00 mg was better. The reaction performance in single channel was better than that in multi-channel.%考察了催化剂壁载方式、涂层载体和Pd负载量对微通道内的硝基苯气-液-固三相催化加氢反应的影响以及其并行放大效应.结果表明,与溶胶-凝胶法相比,浸渍法制备的催化剂涂层性能较好,其转化率、选择性分别达到89.2%和93.8%;采用强酸性、大比表面积的载体有利于反应性能的提高;活性组分Pd负载量为2.00 mg,催化剂活性较好;单通道微反应器内硝基苯加氢反应过程的转化率和选择性均高于多通道微反应器.

  19. Reducción catalítica selectiva de NOx usando nanopartículas de ferritas Cu1-XCoXFe2O4 como catalizador

    Directory of Open Access Journals (Sweden)

    Sarah Briceño1*

    2009-12-01

    Full Text Available Nanostructured catalysts AB2O4 spinel type oxides (A = Co and B = Cu were prepared by the sol-gel self-combustion method using citric acid as precursor. They were characterized by X-ray diffraction (XRD, Scanning Electron Microscopy (SEM, Transmission Electron Microscopy (TEM and Catalytic activity tests, which have proven to be effective for selective catalytic reduction of NOx using hydrocarbon as a reducing agent (SCR-HC in a temperature range 250 - 450 ° C, reaching up to 40% conversion of NO and 100% selectivity towards the formation of N2

  20. Reducción catalítica de NOx con Pt soportado sobre zeolitas MFI modificadas con Cu, Co, Fe, Mn.

    Directory of Open Access Journals (Sweden)

    Sarah Briceño

    2008-05-01

    Full Text Available The selective catalytic reduction of NO by propane in the presence of excess oxygen has been studied over catalysts based on Pt supported on Fe-ZSM-5, Co-ZSM-5, Cu- ZSM-5 and MnZSM-5. Pure Pt based catalysts are highly active, but produce large amounts of N2O. The bimetallic catalyst was found to offer wider temperature window than that of monocatalysts, and show a synergistic effect by combining high stability and activity of Pt catalysts with the high N2 selectivity of Fe, Co, Cu, Mn supported on MFI catalysts.

  1. Decomposição catalítica de óxidos de nitrogênio Catalytic decomposition of nitrogen oxides

    Directory of Open Access Journals (Sweden)

    Julia María Díaz Cónsul

    2004-06-01

    Full Text Available Contaminant gases in the atmosphere constitute an important problem to be solved in the world. The NOx gases produced as a consequence of engine high temperatures are deleterious to environment and human health, as they promote acid rain and can act in the same way as freons in the destruction of the ozone layer in the stratosphere. In this review, three way and selective reduction catalysts for decomposition of these contaminant gases are described. Details about conditions and problems, such as catalyst poisoning, and the search for new catalysts are shown.

  2. Redução catalítica seletiva de óxidos de nitrogênio sobre hematita contendo cobre

    OpenAIRE

    Ferreira, Hadma Sousa; Oliveira, Soraia Jesus; Varela, Maria do Carmo Rangel Santos; Urquieta-González,Ernesto A.; Martins, Leandro [UNESP; Fierro, José Luís Garcia; Marchetti, Sérgio G.

    2007-01-01

    p. 611-615,May/June. The activity of copper-doped hematite in the SCR with propane, in the presence of oxygen, was evaluated in this work. It was found that copper sulfate led to the production of solids with different specific surface areas depending on the amount of copper. The sulfur and copper species were mainly located on the surface. The copper-containing catalysts were more active in the reduction of nitrogen oxides and less active in the propane oxidation as compared to pure hemat...

  3. Los debates del Estatuto de Autonomía de Cataluña en las cortes republicanas (mayo-agosto de 1932. El idioma catalán y el sistema escolar

    Directory of Open Access Journals (Sweden)

    Xavier Tornafoch Yuste

    2008-12-01

    Full Text Available La discusión del Estatuto de Cataluña en el marco de la constitución del nuevo régimen republicano, surgido de las elecciones municipales del 12 de abril de 1931, evidenció las diferencias que persistían en el seno de la comunidad política española sobre esta cuestión. Los partidos republicanos catalanes, decididamente favorables al autogobierno de Cataluña se enfrentaron en las Cortes a la mayoría de organizaciones españolas, de derecha y de izquierda, reacias a conceder una autonomía política a la región catalana. Los dos aspectos que más debate suscitaron fueron la oficialidad del idioma catalán y el sistema escolar. Esta polémica parlamentaria se llevó a cabo entre los meses d emayo y agosto del año 1932._____________________ABSTRACT:The discusion of the Statute of Catalonia in the framework of the constitution of the new one republican state, arisen of the lections of April 12, 1931, showed the differences that persisted in the breast of the political community Spanish on this question. The republican parties Catalonians, determined favorable to self-government of Catalonia they were faced in the Courts to the Spanish majority of organizations, of riht and of left, reluctant to grant a political autonomy to the Catalonian region. The two aspects that more debates stirred up were the official character of the Catalonian language and the school system. This parliamentary polemics was carried out among the months of May and August of the year 1932.

  4. Repensando los estudios de sistemas de innovación. El sistema catalán de innovación como lugar estratégico de investigación

    Directory of Open Access Journals (Sweden)

    Ahedo, Manuel

    2012-02-01

    Full Text Available The system of innovation or innovation system approach has brought a profound change and improvement in the understanding of the innovation process, mainly by taking into account the national, regional, sectoral and technological dimensions and factors. However, despite its clear knowledge accumulation, it still has analytical limitations with regard to old questions and also to emerging issues. This article looks at the Catalan innovation system, as a strategic research case, in order to point out which are these questions and issues, and to propose some possible ways to advance in the analytical solution, and in general in moving towards a better understanding of the innovation processes in the globalizing capitalism of the 21st century society and economy.

    El enfoque de sistema de innovación ha generado un profundo cambio y mejora en el análisis de los procesos de innovación, al tener en cuenta los contextos nacionales, regionales, sectoriales y tecnológicos. Sin embargo, tras varias décadas de acumulación de conocimiento, el enfoque de sistemas de innovación presenta todavía una serie de limitaciones en la comprensión de algunas cuestiones tanto tradicionales como nuevas o emergentes. Este artículo explora el sistema catalán de innovación, considerado un caso estratégico de investigación, para indicar cuáles son esas cuestiones y retos, y proponer algunas vías posibles para el avance analítico y un mejor conocimiento de los procesos de innovación en el emergente capitalismo global de la sociedad y economía del siglo XXI.

  5. Valorização e aproveitamento de subprodutos lácticos: extração de proteínas e hidrogenação catalítica da lactose

    Directory of Open Access Journals (Sweden)

    Carlos Enrique Jeronimo

    2012-01-01

    Full Text Available A indústria de produção de queijo tem no seu ciclo de produção a geração de um subproduto muito rico em proteínas e lactose, chamado soro de queijo. Esse resíduo, atualmente, tem algumas aplicações em alimentos, mas que não adiciona valor para o real conteúdo nutricional e econômico que esse tem em seu potencial. Neste trabalho objetiva-se uma maior valoração do soro de queijo,onde foram conduzidos estudos para a recuperação de proteínas e conversão catalítica da lactose residual em um poliol de elevadovalor econômica, chamada lactitol. Os resultados mostraram alta eficiência de remoção de proteínas, na ordem de 93% e a conversãode lactose comercial em torno de 90% em 150 minutos de reação. A aplicabilidade de soro de leite, no entanto, requer a remoção dosíons cloreto, como forma de pré-tratamento.Abstract The cheese-producing industry has in its production cycle to generate a product very rich in protein and lactose, called cheese whey. The waste currently has some food applications, but that does not add value to the real nutritional content and economical product that leverages. In order, therefore, a greater appreciation of cheese whey, studies were conducted for the recovery of proteins and the catalytic conversion of lactose into a polyol of high economic value,called lactitol. The results showed high removal efficiency ofproteins in the order of 93% and the conversion of commerciallactose around 90% in 150 minutes of reaction. The applicabilityof whey, however, requires further testing to remove the chlorideions present in serum.

  6. Kinetics Studies On Polyphenoloxidase Catalize P-chlorophenol Oxidzing Reaction in onaqueous System%多酚氧化酶在非水相中催化对氯苯酚氧化反应的动力学研究

    Institute of Scientific and Technical Information of China (English)

    李华; 霍瑞贞

    2000-01-01

      In experiment,the polyphenoloxidase was extracted from mushroom by using acetone precipitating method threetimes. And then, it was immobilized by using the absorbentdeposition method with porous glass powder as carriers,It wasstudied to catalize p-chlorophenol oxidizing reaction inchloroform, complys with Michaelis-Menten dynamicmodel.And themoisture content in organic solvent directly affected thecatalytic activity of mushroom polyphenoloxidase. Theoptimum reaction condition for the catalyrtic oxidation of p-chlorophenol in chloroform was determined: pH:7, temperature:25°C, moisture content: 0.5%(v/v).The measured value of dynamic parameters was 29.45kJ. mol-1 for apparent activationenergy,1.058mol. L-1 for Michaelis-Menten kinetics and 9.074×10-2 min-1 for the maximum reaction rate.%  本文用丙酮沉淀法从蘑菇中提取多酚氧化酶,以多孔玻璃粉为载体,用吸附沉积法将酶固定,研究了该酶在氯仿介质中催化对氯苯酚氧化反应的机理遵循米氏(Michaelis-Menten)动力学方程;而且,在有机介质中含水率大小直接影响酶的催化活性.实验测得反应的最佳条件为pH=7.0,温度为25°C,含水率为0.5%(v/v);表观活化能Ea=29.54kJ . mol-1,米氏常数Km=1.058mol . dm-3,最大反应速率rmax=90.74×10-3min-1.

  7. Estudo da influência de resíduos catalíticos na degradação de plásticos reciclados (Blenda HDPE/PP e PET provenientes de lixo urbano

    Directory of Open Access Journals (Sweden)

    Santos Amélia S. F.

    1999-01-01

    Full Text Available A degradação derivada do processamento, uso, descarte, lavagem e reprocessamento foram caracterizados neste estudo. Para o HDPE/PP pós-consumo, a degradação foi estudada em função da presença de garrafas de HDPE/LDPE reprocessadas (recicladas e da presença de tampas e rótulos de LDPE e PP. Esses materiais mostraram uma influência significativa na degradação total de HDPE/PP apenas quando presentes em conjunto. Os resíduos que apresentaram menor estabilidade termo-oxidativa foram os rótulos e tampas de LDPE e PP. As análises usadas na caracterização da influência destes resíduos foram espectroscopia do Infra-vermelho (IR e Calorimetria Diferencial Exploratória (tempo de indução oxidativa - OIT. Além disso, a degradação do PET foi estudada em função das condições de lavagem e da presença de resíduos de soda cáustica e adesivo. Foram usadas medidas de viscosidade intrínseca e de titulação para caracterizar estas variáveis. Foi observado que apesar do uso de altas temperaturas (80 ºC durante a lavagem, a extensão de tempo desta etapa (5 ou 15 min não afetou a degradação do PET, pelo menos não em níveis detectáveis pelas análises. No entanto, a remoção do resíduo de adesivo mostrou uma influência significativa na degradação catalítica do PET.

  8. Metodología del análisis sectorial en el sistema agroalimentario aplicada al subsector oleícola catalán. Evaluación de la competitividad, el progreso tecnológico y la eficiencia económica empresarial

    OpenAIRE

    Fortuny Santos, Jordi

    2002-01-01

    El objetivo global de esta investigación es examinar como el sector catalán del aceite de oliva podría mejorar sus resultados empleando las herramientas de la planificadas estratégica y de la dirección estratégica. Se analizan los factores del entorno externo e interno que afectan a las empresas. El análisis del entorno exterior incluye factores políticos, demográficos, culturales y económicos.Se han estudiado las tendencias en los principales países productores y consumidores de aceite de ol...

  9. Metodología del análisis sectorial en el sistema agroalimentario aplicada al subsector oleícola catalán. Evaluación de la competitividad, el progreso tecnológico y la eficiencia económica empresarial

    OpenAIRE

    Fortuny Santos, Jordi

    2002-01-01

    El objetivo global de esta investigación es examinar como el sector catalán del aceite de oliva podría mejorar sus resultados empleando las herramientas de la planificadas estratégica y de la dirección estratégica. Se analizan los factores del entorno externo e interno que afectan a las empresas. El análisis del entorno exterior incluye factores políticos, demográficos, culturales y económicos.Se han estudiado las tendencias en los principales países productores y consumidores de aceite de ol...

  10. Modelado cinético y matemático de la reacción de gasificación catalítica de la glucosa en agua en condiciones supercríticas para la producción de hidrógeno

    OpenAIRE

    Zalamea, Silvana; Mejía, William; Serrano, José

    2016-01-01

    El Hidrógeno producido a partir de la biomasa procedente de los residuos de la planta de banano es considerado como un combustible altamente eficiente. Uno de los métodos más limpios para su obtención es la gasificación catalítica en agua en condiciones supercríticas, en donde se transforman los polisacáridos constitutivos de la biomasa (celulosa, hemicelulosa y lignina) en productos gaseosos de elevado valor. En el desarrollo de la reacción de gasificación es importante el dis...

  11. Exceptional Reductions

    CERN Document Server

    Marrani, Alessio; Riccioni, Fabio

    2011-01-01

    Starting from basic identities of the group E8, we perform progressive reductions, namely decompositions with respect to the maximal and symmetric embeddings of E7xSU(2) and then of E6xU(1). This procedure provides a systematic approach to the basic identities involving invariant primitive tensor structures of various irreprs. of finite-dimensional exceptional Lie groups. We derive novel identities for E7 and E6, highlighting the E8 origin of some well known ones. In order to elucidate the connections of this formalism to four-dimensional Maxwell-Einstein supergravity theories based on symmetric scalar manifolds (and related to irreducible Euclidean Jordan algebras, the unique exception being the triality-symmetric N = 2 stu model), we then derive a fundamental identity involving the unique rank-4 symmetric invariant tensor of the 0-brane charge symplectic irrepr. of U-duality groups, with potential applications in the quantization of the charge orbits of supergravity theories, as well as in the study of mult...

  12. The study of partial and excess molar volumes for binary mixtures of nitrobenzene and benzaldehyde with xylene isomers from T = (298.15 to 318.15 K and P = 0.087 MPa

    Directory of Open Access Journals (Sweden)

    Hamid R. Rafiee

    2016-09-01

    Full Text Available Based on density measurements, partial and excess molar volumes for binary mixtures of nitrobenzene and benzaldehyde with three isomers of xylene have been measured. The whole range of composition and temperatures from T = (298.15 to 318.15 K at ambient pressure 0.087 MPa, has been considered. The excess molar volumes were negative and decreased by increasing temperature for all mixtures which are explained based on intermolecular interactions. Excess molar volumes for solutions including nitrobenzene were absolutely larger than benzaldehyde binary mixtures. The partial and excess molar volumes for each component have been appraised and reported. The excess molar volumes have been successfully fitted to Redlich–Kister equation.

  13. Consorcio microbiano nativo con actividad catalítica para remoción de índigo y surfactantes en agua residual industrial textil a través de una matriz de inmovilización

    Directory of Open Access Journals (Sweden)

    Lliana Guerrero Porras

    2014-06-01

    Full Text Available Título en ingles: Microbial consortium native catalytically active for removal of indigo and surfactants in textile industry wastewater through an immobilization matrixTítulo corto: Consorcio microbiano nativo con actividad catalítica para remoción de índigoResumen: El siguiente estudio tuvo como objetivo aislar seis diferentes cepas bacterianas  provenientes de las descargas de agua utilizadas en la tintura de hilo con colorante índigo, que tuviesen capacidad de degradación de compuestos orgánicos del tinte índigo y tres surfactantes de tipo no iónicos.  Igualmente, se evaluaron diferentes medios de soporte para inmovilizar las cepas seleccionadas. Las cepas con mejor capacidad de decoloración se combinaron para conformar cuatro consorcios (I, II, III, y IV con el fin de potenciar el proceso de decoloración, considerando que la sinergia y el complemento de actividades metabólicas de cultivos mixtos dentro de una comunidad microbiana incrementan la eficiencia de remoción de carga orgánica. Los porcentajes de remoción que se alcanzaron fueron 64, 73, 76 y 59 %, respectivamente. Los cultivos individuales no presentaron porcentajes de remoción superiores a los reportados por los consorcios, lo que permite pensar en su utilización para la remoción de tintes índigos en aguas residuales.Palabras claves: aislamiento, biodegradación, índigo, surfactantes no iónicos, consorcio bacteriano.Abstract: The aim of this study was isolate six different bacterial strains from water discharges used in dyeing yarn with indigo, capable of degradation of organic compounds with indigo dye and three nonionic type surfactants. Similarly, various supporting media were evaluated for immobilizing the selected strains. Strains with better capacity were combined to form four consortia (I, II, III, and IV in order to enhance the bleaching process, whereas synergy and complement metabolic activities of mixed cultures within a community increase

  14. Craqueamento catalítico de polietileno em condições de refinaria: produção de frações combustíveis Catalytic cracking of polyethylene under refinery conditions: production of combustible fractions

    Directory of Open Access Journals (Sweden)

    Alessandra M. Ribeiro

    2006-12-01

    Full Text Available Este trabalho foi realizado em uma unidade de teste de microatividade para estudar o processo de craqueamento catalítico das cargas combinadas de polietileno de baixa densidade e polietileno de alta densidade com vaselina, frente a catalisadores comerciais de FCC (alta e baixa atividades, para avaliar a produção das frações combustíveis (gasolina, diesel e resíduo. As cargas combinadas de PEBD e PEAD/vaselina foram processadas em condições de refinaria. Para as cargas de PEBD/vaselina, a 2, 6 e 10% p/p, a produção da fração gasolina foi favorecida pelo catalisador de alta atividade, enquanto que a carga de PEAD/vaselina a 2% p/p, para produção da mesma fração, o catalisador de baixa atividade apresentou melhor eficiência. Todas as cargas combinadas, nas diversas concentrações, mostraram que o material inerte (caulim apresenta maior atuação, na produção da fração resíduo, indicando a ocorrência preferencial de craqueamento térmico.This work was carried out in an unit of microactivity test, to study the process of combined feeds of low density and high density polyethylenes with vaseline and commercial FCC catalysts (of low and of high activities, to evaluate the production of fuel fractions (gasoline, diesel and residue. The combined feeds of PEBD and PEAD/vaseline, at different concentrations, were processed under refinery conditions. For feeds of PEBD/vaseline at 2, 6 and 10% w/w, production of the gasoline fraction was favored with the high-activity catalyst, while for the PEAD/vaseline feed at 2%, in the production of the same fraction, the low-activity catalyst presented better performance. For all the combined feeds, in all concentrations, the inert material showed better performance for the production of residue fraction, indicating the preferential occurrence of thermal cracking.

  15. Synthesis of 3,4-methylenedioxy-nitrobenzene from catechol%从邻苯二酚合成3,4-亚甲二氧基硝基苯

    Institute of Scientific and Technical Information of China (English)

    黄晓瑛; 宁斌科; 王列平; 刘军; 黄林; 钱一石

    2011-01-01

    以邻苯二酚为原料,经亚甲基化和硝化两步反应,得到目标产物3,4-亚甲二氧基硝基苯.亚甲基化反应最佳温度为120℃;硝化反应中,1,2-亚甲二氧基苯与硝酸最佳物质的量比为1:1.3,硝酸浓度为50%.反应总收率为90.7%,纯度达到99.9%.%Catechol was used as the starting material to give 3,4-methylenedioxy-nitrobenzene which was synthesized by the process of methylenation and nitration. The optimum temperature of the methylenation was 120℃. The optimum conditions of nitration were;the molar ratio of 1,2-(methylenedioxy)benzene to nutrate was 1: 1.3, concentration of HNO3 was 50%. The total yield and the purity of the product were 90.7% and 99.9%.

  16. Lymphedema Risk Reduction Practices

    Science.gov (United States)

    ... now! Position Paper: Lymphedema Risk Reduction Practices Category: Position Papers Tags: Risks Archives Treatment risk reduction garments surgery obesity infection blood pressure trauma morbid obesity body weight ...

  17. Aspectos fonéticos del proceso de velarización en las nasales del español y del catalán (Phonetic aspects of velarization process in Spanish and Catalan nasals

    Directory of Open Access Journals (Sweden)

    Ana María Fernández Planas

    2012-12-01

    Full Text Available La producción de las nasales exige simultáneamente una oclusión dentro de la boca y una salida de aire por el canal rinofaríngeo y esta característica las distingue de las demás articulaciones de los inventarios de las lenguas. La salida de aire por la nariz es el requisito articulatorio más definitorio y permite que la oclusión bucal no precise unos requisitos tan estrictos con lo cual se puede adaptar fácilmente a la articulación siguiente cuando la nasal aparece en posición implosiva. Ante oclusiva velar es sabido que la nasal sufre un proceso de velarización y atrasa su punto de articulación hacia la parte posterior de la cavidad bucal. El presente trabajo pretende profundizar en este tipo de coarticulación en grupos consonánticos "nasal + oclusiva velar" para evaluar aspectos fonéticos, necesariamente alofónicos, en español y catalán. Concretamente se profundiza en el efecto de varios factores (la velocidad de habla, la ocurrencia de la nasal en sílaba tónica o átona, la presencia de una frontera morfológica o no en el grupo consonántico y la sordez-tensión o sonoridad-laxitud de la oclusiva siguiente a partir de los datos obtenidos de tres informantes en cada lengua en diversos ítems repetidos cada uno de ellos cuatro veces y analizados mediante el electropalatógrafo WinePG. Los resultados señalan la importancia de los factores estudiados, especialmente de la tensión o la sonoridad de la oclusiva siguiente. Asimismo se constata la tendencia en habla rápida a la hipoarticulación a diferencia de lo que sucede en habla lenta, velocidad que favorece la hiperarticulación y la pérdida de la asimilación en algunas muestras de dos de los informantes. Este hecho unido a la existencia de emisiones que podrían presentar un cierto tipo de asimilaciones parciales nos hace pensar que el proceso de asimilación debe ser visto más bien de forma gradual que categórica. (Nasal consonants are distinguished from other

  18. Seleção de concretos refratários densos antierosivos para unidades de craqueamento catalítico fluidizado de petróleo Selection of dense antierosive refractory castables for fluid catalytic cracking units

    Directory of Open Access Journals (Sweden)

    F. A. S. Serra

    2012-03-01

    Full Text Available Na indústria petroquímica a unidade de craqueamento catalítico fluidizado de petróleo é um importante equipamento para aplicação de concretos refratários devido à necessidade de se obter produtos especializados. Normalmente, a seleção destes materiais é baseada na análise química e em medidas de densidade aparente, resistência mecânica por compressão uniaxial e erosimetria a frio. Para avaliação dos requisitos de seleção usuais, cinco concretos de alta alumina, sendo três de baixo teor de cimento e dois convencionais de uso comercial, foram avaliados por resistência à compressão e erosimetria a frio. Testes complementares que atualmente não são utilizados no processo de seleção também foram realizados, tais como: resistência ao choque térmico, módulo de ruptura a quente e exposição em atmosfera de CO. A análise mostrou que as especificações vigentes são baseadas principalmente na experiência com a utilização de produtos não originalmente projetados para esta aplicação e que o desenvolvimento de produtos mais adequados é inibido pelas restrições das especificações atuais. Também se verificou que a seleção é limitada pela falta de ensaios que avaliem o desempenho em condições mais próximas das de uso. Neste sentido, o teste de resistência à deposição de carbono pela exposição em atmosfera de CO mostrou-se interessante por contribuir para uma melhor seleção dos concretos refratários densos antierosivos.In the petrochemical industry the fluidized catalytic cracking unit is an important vessel for refractory castables application due the necessity of obtaining specialized products. Usually, the selection of these materials is based on the chemical analysis, apparent density, cold crushing strength and cold erosion test. For the evaluation of the present selection requirements, five high-alumina castables, being three of low cement and two conventional of commercial use, were

  19. Diego Catalán, El archivo del romancero, Patrimonio de la Humanidad: historia documentada de um siglo de historia, Madrid, Fundación Menéndez Pidal - Seminario Menéndez Pidal, Universidad Complutense, 2001, 2 vols., 678 pp. + 431 ilustrações

    OpenAIRE

    Fontes, Manuel da Costa

    2003-01-01

    Este magnífico livro é uma história pormenorizada, rica, íntima e carinhosa do grande arquivo romancístico fundado por Ramón Menéndez Pidal, e da sua continuação e ampliação sob a guia de Diego Catalán, neto e herdeiro intelectual do fundador. Ramón Menéndez Pidal (1869–1968), pai da Filologia Românica em Espanha, deixou uma vasta obra de carácter histórico, linguístico e literário que continua a ser um ponto de partida indispensável para quem se interesse pelo estudo da Idade Média Pen...

  20. A transformação dos mecanismos de materialização política das identidades nacionais: o Estado autonômico espanhol e a emergência das autonomias-nação basca e catalã

    Directory of Open Access Journals (Sweden)

    Felipe Vasconcelos Romão

    2013-12-01

    Full Text Available Este artigo visa a abordar a forma como duas identidades nacionais concretas, a basca e a catalã, potencializadas pelos respectivos nacionalismos e pelo processo de democratização espanhol, conseguiram materializar-se política e legalmente naquilo que qualificamos como autonomias-nação. Para chegar à análise deste estudo de caso, começa por percorrer o papel do Estado-nação e a relação entre os conceitos de Estado e nação. Destaca de forma especial a emergência de novas unidades políticas, que o autor denomina autonomias-nação, que constituem um autêntico desafio ao conceito tradicional de soberania.

  1. Testing of some azo dyes and their reduction products for mutagenicity using Salmonella typhimurium TA 1538.

    Science.gov (United States)

    Garner, R C; Nutman, C A

    1977-07-01

    A series of ten azo dyes as well as various single ring aromatic amines substituted on the benzene ring were tested for bacterial mutagenicity with Salmonella typhimurium TA 1538 using a soft-agar overlay method. Two dyes, sudan 2 and chrysoidin induced mutation but only in the presence of a rat liver preparation. Chrysoidin was the more active. Testing of its reduction products, aniline and 1,2,4-triaminobenzene showed a liver metabolite of the latter compound could be responsible for the mutagenic effect, having a comparable mutagenicity with 1,2-diamino-4-nitro-benzene, one of the mutagenic constituents of hair dyes. Structure-activity studies on a series of ring-substituted anilines indicated that mutagenic activity required at least two positions to be substituted with either amino or nitro groups, or one of each. The bacteria as well as the liver enzyme preparation may partake in the activation of these chemicals. The correlation between mutagenicity and carcinogenicity for this group of compounds is discussed.

  2. Vowel Reduction in Japanese

    Institute of Scientific and Technical Information of China (English)

    Shirai; Setsuko

    2009-01-01

    This paper reports the result that vowel reduction occurs in Japanese and vowel reduction is the part of the language universality.Compared with English,the effect of the vowel reduction in Japanese is relatively weak might because of the absence of stress in Japanese.Since spectral vowel reduction occurs in Japanese,various types of researches would be possible.

  3. 植物油改性纳米铁修复硝基苯污染地下水的研究%Degradation of nitrobenzene in groundwater using vegetable oil modified zero-valent-iron

    Institute of Scientific and Technical Information of China (English)

    温春宇; 王敏; 董军; 杜宇; 刘航

    2013-01-01

      实验室条件下,液相还原法FeSO4·7H2O和KBH4反应制备纳米铁,用XRD、TEM对其性能进行表征,结果表明该纳米铁平均粒径为50 nm,主要成分为α-Fe0。实验室进一步制备植物油改性纳米铁,TEM表明油膜均匀包覆在纳米铁颗粒表面,且纳米铁粒子分布均匀,分散较好。厌氧条件下,纳米铁与硝基苯反应,研究纳米铁和植物油改性纳米铁对硝基苯的降解性能,以及不同初始铁投加量、植物油质量分数、初始 pH 对硝基苯降解的影响。研究表明,纳米铁和植物油改性纳米铁均对硝基苯有较强的降解能力,理论摩尔比下,1 h内纳米铁和改性纳米铁对硝基苯的降解率达99.85%和56.74%;油膜质量分数为1%和2%的改性纳米铁降解硝基苯效果较好;随着初始纳米铁投加量的增加,硝基苯的降解越快;初始pH对改性纳米铁降解硝基苯有一定影响,酸性条件有利于改性纳米铁降解硝基苯。%Nanoscale zero-valent iron (ZVI) is prepared in the laboratory by liquid phase reducing method using KBH4 and FeSO4·7H2O. Then the ZVI is modified by vegetable oil, so vegetable oil modified zero-valent iron is prepared. XRD and TEM shows that the average particle size of ZVI prepared is 50 nm and its main component isα-Fe0. As to vegetable oil modified ZVI is successfully surrounded by the oil membrane, and it is well-dispersed, less aggregation of vegetable oil modified ZVI is observed. The experiments are conducted in anaerobic conditions, zero-valent iron and nitrobenzene is reacted to investigate the removal ability of ZVI and modified ZVI, the influence of different oil mass fraction, initial iron mass, initial pH. Results indicated that both ZVI and modified ZVI have the ability to degrade nitrobenzene, in 1 hour, degradation rate of ZVI and oil-modified ZVI has reached to 99.85%and 56.74%respectively;the optimized oil mass fraction tended to be 1%and 2%;As the

  4. 葡萄糖和硝基苯为混合燃料时MFC的产电特性研究%Power Generation from Glucose and Nitrobenzene Degradation Using the Microbial Fuel Cell

    Institute of Scientific and Technical Information of China (English)

    李婕; 刘广立; 张仁铎; 罗勇; 张翠萍; 李明臣; 全向春

    2010-01-01

    通过构建双极室微生物燃料电池(microbial fuel cell,MFC ),以铁氰化钾溶液为阴极电子受体,以硝基苯(nitrobenzene,NB)和葡萄糖为混合燃料,研究MFC的产电特性和NB的降解情况.结果表明,在外阻为1000Ω的条件下,随着NB初始浓度的增加,双极室MFC的产电特性明显受到抑制.当葡萄糖浓度为1000m岁L,NB初始浓度分别为0、50、150、250mg/L时,MFC的运行周期逐渐缩短,分别为55.7、51.6、45.9、32.2 h;最大输出电压分别为670、597、507、489 mV;最大体积功率密度分别为28.57、20.42、9.29、8.47W/m3;电荷量分别为65.10、43.50、35.48、30.32 C.MFC利用NB和葡萄糖为混合嫩料,可以在稳定地输出电能的同时实现有机物高效降解,MFC对NB去除率高达100%,对COD的去除率达到87%~98%.但以250mg/L NB为单一嫩料时,MFC无明显产电现象.DGGE图谱表明NB的加人改变了MFC阳极电极上微生物的群落结构.

  5. Infinitary Combinatory Reduction Systems: Normalising Reduction Strategies

    NARCIS (Netherlands)

    Ketema, Jeroen; Simonsen, Jakob Grue

    2010-01-01

    We study normalising reduction strategies for infinitary Combinatory Reduction Systems (iCRSs). We prove that all fair, outermost-fair, and needed-fair strategies are normalising for orthogonal, fully-extended iCRSs. These facts properly generalise a number of results on normalising strategies in fi

  6. Local reduction in physics

    Science.gov (United States)

    Rosaler, Joshua

    2015-05-01

    A conventional wisdom about the progress of physics holds that successive theories wholly encompass the domains of their predecessors through a process that is often called "reduction." While certain influential accounts of inter-theory reduction in physics take reduction to require a single "global" derivation of one theory's laws from those of another, I show that global reductions are not available in all cases where the conventional wisdom requires reduction to hold. However, I argue that a weaker "local" form of reduction, which defines reduction between theories in terms of a more fundamental notion of reduction between models of a single fixed system, is available in such cases and moreover suffices to uphold the conventional wisdom. To illustrate the sort of fixed-system, inter-model reduction that grounds inter-theoretic reduction on this picture, I specialize to a particular class of cases in which both models are dynamical systems. I show that reduction in these cases is underwritten by a mathematical relationship that follows a certain liberalized construal of Nagel/Schaffner reduction, and support this claim with several examples. Moreover, I show that this broadly Nagelian analysis of inter-model reduction encompasses several cases that are sometimes cited as instances of the "physicist's" limit-based notion of reduction.

  7. Reduction in language testing

    DEFF Research Database (Denmark)

    Dimova, Slobodanka; Jensen, Christian

    2013-01-01

    /video recorded speech samples and written reports produced by two experienced raters after testing. Our findings suggest that reduction or reduction-like pronunciation features are found in tested L2 speech, but whenever raters identify and comment on such reductions, they tend to assess reductions negatively......This study represents an initial exploration of raters' comments and actual realisations of form reductions in L2 test speech performances. Performances of three L2 speakers were selected as case studies and illustrations of how reductions are evaluated by the raters. The analysis is based on audio...

  8. Modern Reduction Methods

    CERN Document Server

    Andersson, Pher G

    2008-01-01

    With its comprehensive overview of modern reduction methods, this book features high quality contributions allowing readers to find reliable solutions quickly and easily. The monograph treats the reduction of carbonyles, alkenes, imines and alkynes, as well as reductive aminations and cross and heck couplings, before finishing off with sections on kinetic resolutions and hydrogenolysis. An indispensable lab companion for every chemist.

  9. 蔗糖改性纳米铁原位反应带对硝基苯污染的模拟修复研究%Simulated remediation for nitrobenzene pollution with in-situ reactive zone of sucrose-modified nanoscale zero valent iron

    Institute of Scientific and Technical Information of China (English)

    李卉; 赵勇胜; 韩占涛; 张威

    2015-01-01

    In order to study the remediation effeciency for nitrobenzene pollution, in-situ reactive zone of modified nanosale zero valent iron was created in one-dimensional simulation columns using prepared slurry, and the persistence of its function was also assessed through the calculation of permeability change. The results of simulated experiments show that the removal efficiency of nitrobenzene was 45%~80%, and the changing process of the permeability of the reactive zone could be divided into thress stages: rapid decline in 0~10d, slow decline in 10~30 d and stable stage in 30~60d with average decrease of 53.2%. Still, the reactive zone kept favourable operation without blocking in different aquifer conditions, which proved that the zone of SM-NZVI could continue to remediate availably. Larger particle size of aquifer medium and suspension concentration resulted in higher degradation efficiency of nitrobenzene which increased by 23.7% and 13.7%, respectively. However, higher flow velocity of underground water and pollutant concentration were adverse to the removal of nitrobenzene which both decreased by 46.8% or so. The ratio of iron to nitrobenzene participating in the reaction actually in each zone was 11.2, 17.9, 12.6, 3.3 and 25.7, respectively, it means that the utilization percentage of SM-NZVI particles was relatively low and thus excess suspension should be injected to the underground for ideal remediation results.%在一维模拟装置中创建改性纳米铁原位反应带,研究反应带对硝基苯污染的修复情况,并通过反应带渗透性变化对其可持续修复能力进行评估.模拟试验结果表明:不同条件下硝基苯的去除率为45%~80%;反应带渗透性变化过程按时间分为3个阶段,分别是0~10d的快速下降期、10~30d的缓慢下降期和30~60d的稳定期,平均下降了53.2%,堵塞现象未发生,反应带可持续修复能力较好.较大的介质粒径和浆液浓度使污染物降解效率增加,硝

  10. 硝基苯气相氟代脱硝反应热安全性的理论研究%Theoretical Study on Thermal Safety of Gas Phase Fluorodenitration of Nitrobenzene

    Institute of Scientific and Technical Information of China (English)

    程亮; 黄勇; 王新颖; 王凯全; 陈海群

    2011-01-01

    The mechanism of gas phase fluorodenitration of nitrobenzene leading to fluorobenzene was studied using Gaussian 98 program and DFT method at the B3LYP/6-31G( D) level. Along with the calculation of intrinsic reaction coordinate (IRC), the optimization and calculation of statistic thermodynamics functions of reactants, products, intermediates and transition states, thermal safety of the process were analyzed. Theoretical study shows that this SN2 nucleophilic substitution reaction has low barrier, the energy that the reaction needs can get from the energy released in the process of R -? IM1 and TS3 -> P (279.06 kj/mol,143.34 kj/mol); Compared with the Schiemannn reaction, this reaction is much safer and fits the requirements of the inherent safety design during chemical process development, whose reaction rate drops 3 orders of magnitude. The reaction is much more promising in application.%为研究硝基苯气相氟代脱硝反应的热安全性,采用Gaussian98软件,运用密度泛函理论(DFT) B3 LYP,在6-31G(D)基组水平上,全优化计算气相条件下氟离子对硝基苯进攻的氟代脱硝反应的微观机理,得到反应路径并通过IRC验证,并对反应过程中反应物,各中间体、过渡态、产物进行分子几何构型优化,标准热力学函数计算.理论计算研究表明:该反应属于SN2亲核取代反应;反应能垒较低,反应所需能量可以从过程R→IM1和TS3 →P所释放的能量(279.06 kJ/mol,143.34 kJ/mol)中获得;与席曼反应相比较,该反应速率下降3个数量级,热安全性更高,符合化工工程设计的本质安全化要求,具有广阔的应用前景.

  11. ON THE SYMPLECTIC REDUCTIONS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A symplectic reduction method for symplectic G-spaces is given in this paper without using the existence of momentum mappings.By a method similar to the above one,the arthors give a symplectic reduction method for the Poisson action of Poisson Lie groups on symplectic manifolds,also without using the existence of momentum mappings.The symplectic reduction method for momentum mappings is thus a special case of the above results.

  12. Finding optimal exact reducts

    KAUST Repository

    AbouEisha, Hassan M.

    2014-01-01

    The problem of attribute reduction is an important problem related to feature selection and knowledge discovery. The problem of finding reducts with minimum cardinality is NP-hard. This paper suggests a new algorithm for finding exact reducts with minimum cardinality. This algorithm transforms the initial table to a decision table of a special kind, apply a set of simplification steps to this table, and use a dynamic programming algorithm to finish the construction of an optimal reduct. I present results of computer experiments for a collection of decision tables from UCIML Repository. For many of the experimented tables, the simplification steps solved the problem.

  13. CARBON DIOXIDE REDUCTION SYSTEM.

    Science.gov (United States)

    CARBON DIOXIDE , *SPACE FLIGHT, RESPIRATION, REDUCTION(CHEMISTRY), RESPIRATION, AEROSPACE MEDICINE, ELECTROLYSIS, INSTRUMENTATION, ELECTROLYTES, VOLTAGE, MANNED, YTTRIUM COMPOUNDS, ZIRCONIUM COMPOUNDS, NICKEL.

  14. Avaliação catalítica dos espinélios ZnAl2O4 e ZnAl1,9Eu0,1O4 na transesterificação metílica do óleo de soja

    Directory of Open Access Journals (Sweden)

    P. T. A. Santos

    2015-03-01

    Full Text Available Este estudo objetivou avaliar o efeito da dopagem de európio na estrutura e na morfologia do espinélio ZnAl1,9Eu0,1O4 e seu desempenho como catalisador na transesterificação metílica do óleo de soja. Os pós do espinélio ZnAl1,9Eu0,1O4 foram sintetizados por meio da reação de combustão e caracterizados por difração de raios X (DRX, espectroscopia de absorção óptica na região do infravermelho com transformada de Fourier (FTIR, microscopia eletrônica de varredura e análise termogravimétrica. As reações de transesterificação foram conduzidas a 160 e 180 ºC, razão molar óleo/álcool 1:15, 2% de catalisador e tempo de reação 3 h. Os resultados das caracterizações por DRX e FTIR indicaram a fase espinélio do aluminato e duas bandas de absorção entre 450 e 700 cm-1, características da estrutura de espinélio. Os resultados das reações de transesterificação mostraram que a dopagem de ZnAl2O4 com 0,1 mol de európio favoreceu um aumento na conversão catalítica de 15,8% para 68,7%, indicando que os íons európio tornam o catalisador mais ativo. Aumentando a temperatura da reação de 120 para 180 ºC promoveu um aumento considerável na conversão catalítica de 18,4 para 68,7%, utilizando o catalisador dopado com európio. A conversão do catalisador reutilizado ZnAl1,9Eu0,1O4 mostrou uma redução em cerca de 31% quando foi utilizado pela terceira vez.

  15. Strategies for poverty reduction

    OpenAIRE

    Øyen, Else

    2003-01-01

    SIU konferanse Solstrand 6.-7. October 2003 Higher education has a value of its own. When linked to the issue of poverty reduction it is necessary to ask another set of questions, including the crutial one whether higher education in general is the best tool for poverty reduction.

  16. Strategies for poverty reduction

    OpenAIRE

    Øyen, Else

    2003-01-01

    SIU konferanse Solstrand 6.-7. October 2003 Higher education has a value of its own. When linked to the issue of poverty reduction it is necessary to ask another set of questions, including the crutial one whether higher education in general is the best tool for poverty reduction.

  17. Reduct and Attribute Order

    Institute of Scientific and Technical Information of China (English)

    Su-Qing Han; Jue Wang

    2004-01-01

    Based on the principle of discernibility matrix,a kind of reduction algorithm with attribute order has been developed and its solution has been proved to be complete for reduct and unique for a given attribute order.Being called the reduct problem,this algorithm can be regarded as a mapping R = Reduct(S)from the attribute order space θ to the reduct space R for an information system ,where U is the universe and C and D are two sets of condition and decision attributes respectively.This paper focuses on the reverse problem of reduct problem S = Order(R),i.e.,for a given reduct R of an information system,we determine the solution of S = Order(R)in the space θ.First,we need to prove that there is at least one attribute order S such that S = Order(R).Then,some decision rules are proposed,which can be used directly to decide whether the pair of attribute orders has the same reduct.The main method is based on the fact that an attribute order can be transformed into another one by moving the attribute for limited times.Thus,the decision of the pair of attribute orders can be altered to the decision of the sequence of neighboring pairs of attribute orders.Therefore,the basic theorem of neighboring pair of attribute orders is first proved,then,the decision theorem of attribute order is proved accordingly by the second attribute.

  18. Lymphedema Risk Reduction Practices

    Science.gov (United States)

    ... LSAP Perspective (9) 2017 NLN International Conference Position Paper: Lymphedema Risk Reduction Practices Category: Position Papers Tags: ... and water, pat dry, then apply a topical antibacterial. d. Wear non-constricting protective gear over the ...

  19. Reduction Redux of Adinkras

    CERN Document Server

    Gates,, S James; Stiffler, Kory

    2013-01-01

    We show performing general ``0-brane reduction'' along an arbitrary fixed direction in spacetime and applied to the starting point of minimal, off-shell 4D, $\\cal N$ $=$ 1 irreducible supermultiplets, yields adinkras whose adjacency matrices are among some of the special cases proposed by Kuznetsova, Rojas, and Toppan. However, these more general reductions also can lead to `Garden Algebra' structures beyond those described in their work. It is also shown that for light-like directions, reduction to the 0-brane breaks the equality in the number of fermions and bosons for dynamical theories. This implies that light-like reductions should be done instead to the space of 1-branes or equivalently to the worldsheet.

  20. Breast Reduction Surgery

    Science.gov (United States)

    ... breastfeeding: A systematic review. Journal of Plastic, Reconstructive & Aesthetic Surgery. 2010;63:1688. Kerrigan CL, et al. Evidence-based medicine: Reduction mammoplasty. Plastic and Reconstructive Surgery. 2013;132: ...

  1. Work Truck Idling Reduction

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-03-01

    Hybrid utility trucks, with auxiliary power sources for on-board equipment, significantly reduce unnecessary idling resulting in fuel costs savings, less engine wear, and reduction in noise and emissions.

  2. New Reductive Desulfurization Technology

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ The project for the research of the pulse plasma reductive desulfurization technology undertaken by Huazhong University of Science and Technology recently passed the research achievement appraisal in Wuhan, Hubei province.

  3. Dissimilatory metal reduction.

    Science.gov (United States)

    Lovley, D R

    1993-01-01

    Microorganisms can enzymatically reduce a variety of metals in metabolic processes that are not related to metal assimilation. Some microorganisms can conserve energy to support growth by coupling the oxidation of simple organic acids and alcohols, H2, or aromatic compounds to the reduction of Fe(III) or Mn(IV). This dissimilatory Fe(III) and Mn(IV) reduction influences the organic as well as the inorganic geochemistry of anaerobic aquatic sediments and ground water. Microorganisms that use U(VI) as a terminal electron acceptor play an important role in uranium geochemistry and may be a useful tool for removing uranium from contaminated environments. Se(VI) serves as a terminal electron acceptor to support anaerobic growth of some microorganisms. Reduction of Se(VI) to Se(O) is an important mechanism for the precipitation of selenium from contaminated waters. Enzymatic reduction of Cr(VI) to the less mobile and less toxic Cr(III), and reduction of soluble Hg(II) to volatile Hg(O) may affect the fate of these compounds in the environment and might be used as a remediation strategy. Microorganisms can also enzymatically reduce other metals such as technetium, vanadium, molybdenum, gold, silver, and copper, but reduction of these metals has not been studied extensively.

  4. Reduction zero-knowledge

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yunlei; DENG Xiaotie; LEE C. H.; ZHU Hong

    2004-01-01

    The nature of zero-knowledge is re-examined and the evidence for the following belief is shown:the classic simulation based definitions of zero-knowledge(simulation zero-knowledge)may be somewhat too strong to include some "nice" protocols in which the malicious verifier seems to learn nothing but we do not know how to construct a zero-knowledge simulator for it.To overcome this problem a new relaxation of zero-knowledge,reduction zero-knowledge,is introduced.It is shown that reduction zero-knowledge just lies between simulation zero-knowledge and witness indistinguishability.Under the assumption of existence of one-way permutations a 4-round public-coin reduction zero-knowledge proof system for NP is presented and in practice this protocol works in 3 rounds since the first verifier's message can be fixed once and for all.

  5. The cyclic reduction algorithm

    Science.gov (United States)

    Bini, Dario; Meini, Beatrice

    2009-05-01

    Cyclic reduction is an algorithm invented by G.H. Golub and R. W. Hockney in the mid 1960s for solving linear systems related to the finite differences discretization of the Poisson equation over a rectangle. Among the algorithms of Gene Golub, it is one of the most versatile and powerful ever created. Recently, it has been applied to solve different problems from different applicative areas. In this paper we survey the main features of cyclic reduction, relate it to properties of analytic functions, recall its extension to solving more general finite and infinite linear systems, and different kinds of nonlinear matrix equations, including algebraic Riccati equations, with applications to Markov chains, queueing models and transport theory. Some new results concerning the convergence properties of cyclic reduction and its applicability are proved under very weak assumptions. New formulae for overcoming breakdown are provided.

  6. REDUCTIONS WITHOUT REGRET: SUMMARY

    Energy Technology Data Exchange (ETDEWEB)

    Swegle, J.; Tincher, D.

    2013-09-16

    This paper briefly summarizes the series in which we consider the possibilities for losing, or compromising, key capabilities of the U.S. nuclear force in the face of modernization and reductions. The first of the three papers takes an historical perspective, considering capabilities that were eliminated in past force reductions. The second paper is our attempt to define the needed capabilities looking forward in the context of the current framework for force modernization and the current picture of the evolving challenges of deterrence and assurance. The third paper then provides an example for each of our undesirable outcomes: the creation of roach motels, box canyons, and wrong turns.

  7. Time, Chance, and Reduction

    Science.gov (United States)

    Ernst, Gerhard; Hüttemann, Andreas

    2010-01-01

    List of contributors; 1. Introduction Gerhard Ernst and Andreas Hütteman; Part I. The Arrows of Time: 2. Does a low-entropy constraint prevent us from influencing the past? Mathias Frisch; 3. The part hypothesis meets gravity Craig Callender; 4. Quantum gravity and the arrow of time Claus Kiefer; Part II. Probability and Chance: 5. The natural-range conception of probability Jacob Rosenthal; 6. Probability in Boltzmannian statistical mechanics Roman Frigg; 7. Humean mechanics versus a metaphysics of powers Michael Esfeld; Part III. Reduction: 8. The crystallisation of Clausius's phenomenological thermodynamics C. Ulises Moulines; 9. Reduction and renormalization Robert W. Batterman; 10. Irreversibility in stochastic dynamics Jos Uffink; Index.

  8. Bronchoscopic lung volume reduction

    Directory of Open Access Journals (Sweden)

    M. I. Polkey

    2006-12-01

    Full Text Available Surgical lung volume reduction can improve exercise performance and forced expiratory volume in one second in patients with emphysema. However, the procedure is associated with a 5% mortality rate and a nonresponse rate of 25%. Accordingly, interest has focused on alternative ways of reducing lung volume. Two principle approaches are used: collapse of the diseased area using blockers placed endobronchially and the creation of extrapulmonary pathways. Preliminary data from the former approach suggest that it can be successful and that the magnitude of success is related to reduction in dynamic hyperinflation.

  9. Dimensionality Reduction Mappings

    NARCIS (Netherlands)

    Bunte, Kerstin; Biehl, Michael; Hammer, Barbara

    2011-01-01

    A wealth of powerful dimensionality reduction methods has been established which can be used for data visualization and preprocessing. These are accompanied by formal evaluation schemes, which allow a quantitative evaluation along general principles and which even lead to further visualization schem

  10. Fully Awake Breast Reduction.

    Science.gov (United States)

    Filson, Simon A; Yarhi, Danielle; Ramon, Yitzhak

    2016-11-01

    The authors present 25 cases and an in-depth 4-minute video of fully awake aesthetic breast reduction, which was made possible by thoracic epidural anesthesia. There are obvious and important advantages to this technique. Not only does this allow for intraoperative patient cooperation (i.e., patient self-positioning and opinion for comparison of breasts), meaning a shorter and more efficient intraoperative time, there also is a reduction in postoperative pain, complications, recovery, and discharge times. The authors have also enjoyed great success and no complications with this technique in over 150 awake abdominoplasty/total body lift patients. The authors feel that the elimination of the need for general anesthesia by thoracic epidural sensorial-only anesthesia is a highly effective and efficient technique, with very few disadvantages/complications, providing advantages to both patients and surgeons. Therapeutic, IV.

  11. Injury reduction at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Griffing, Bill; /Fermilab

    2005-06-01

    In a recent DOE Program Review, Fermilab's director presented results of the laboratory's effort to reduce the injury rate over the last decade. The results, shown in the figure below, reveal a consistent and dramatic downward trend in OSHA recordable injuries at Fermilab. The High Energy Physics Program Office has asked Fermilab to report in detail on how the laboratory has achieved the reduction. In fact, the reduction in the injury rate reflects a change in safety culture at Fermilab, which has evolved slowly over this period, due to a series of events, both planned and unplanned. This paper attempts to describe those significant events and analyze how each of them has shaped the safety culture that, in turn, has reduced the rate of injury at Fermilab to its current value.

  12. Jet Engine Noise Reduction

    Science.gov (United States)

    2009-04-01

    Technology Solutions, Lockheed Martin Robert S. Carnes , M.D. NRAC Member, Battelle Memorial Institute MajGen Paul A. Fratarangelo, USMC (Ret) NRAC...Development, Acquisition) (VADM Architzel). The Naval Research Advisory Committee members (Bowes, Bowler, Carnes and Fratarangelo) have broad...Lockheed Martin ADP Boeing: Jet Engine Noise Reduction for Tactical Fighter Aircraft Mr. Tom Kaemming, K. Viswanathan, Ph . D. Tactical Jet Noise

  13. 双频超声-臭氧氧化处理含对硝基苯胺和硝基苯的废水%Treatment of wastewater containing p-nitroaniline and nitrobenzene by bi-frequency ultrasonic enhanced ozonation process

    Institute of Scientific and Technical Information of China (English)

    谭江月

    2011-01-01

    The wastewater containing p-nitroaniline and nitrobenzene was treated respectively by processes of ozonation, frequency ultrasonic enhanced ozonation and bi-frequency ultrasonic enhanced ozonation. The experimental results show that the treatment effect by bi-frequency ultrasonic enhanced ozonation process is the best. Under the optimum conditions of initial wastewater pH 11. ozone flow 30 mg/min, reaction time 50 min, power of the HT-50 ultrasonic generator 50 W , power of the NXG-S ultrasonic generator 110 W, the removal rates of COD, p-nitroaniline and nitrobenzene are 96.4%, 99. 8% and 98. 8% respectively. The water quality of the effluent can meet the first grade discharge standards of GB 8978 - 1996.%分别采用单独臭氧氧化、单频超声协同臭氧氧化、双频超声协同臭氧氧化处理含对硝基苯胺和硝基苯的废水.实验结果表明,双频超声协同臭氧氧化处理废水的效果明显优于单频超声协同臭氧氧化和单独臭氧氧化.在废水初始 pH 为 11、臭氧流量为 30 mg/min、反应时间为 50 min、HT-50 型超声波发生器功率为 50 W、NXG-S 型超声波发生器功率为 110 W 的最佳条件下,COD、对硝基苯胺和硝基苯的去除率分别为 96.4%、99.8%和 98.8%.处理后水质达到 GB8978-1996的一级排放标准.

  14. Reduction of turbomachinery noise

    Science.gov (United States)

    Waitz, Ian A. (Inventor); Brookfield, John M. (Inventor); Sell, Julian (Inventor); Hayden, Belva J. (Inventor); Ingard, K. Uno (Inventor)

    1999-01-01

    In the invention, propagating broad band and tonal acoustic components of noise characteristic of interaction of a turbomachine blade wake, produced by a turbomachine blade as the blade rotates, with a turbomachine component downstream of the rotating blade, are reduced. This is accomplished by injection of fluid into the blade wake through a port in the rotor blade. The mass flow rate of the fluid injected into the blade wake is selected to reduce the momentum deficit of the wake to correspondingly increase the time-mean velocity of the wake and decrease the turbulent velocity fluctuations of the wake. With this fluid injection, reduction of both propagating broad band and tonal acoustic components of noise produced by interaction of the blade wake with a turbomachine component downstream of the rotating blade is achieved. In a further noise reduction technique, boundary layer fluid is suctioned into the turbomachine blade through a suction port on the side of the blade that is characterized as the relatively low-pressure blade side. As with the fluid injection technique, the mass flow rate of the fluid suctioned into the blade is here selected to reduce the momentum deficit of the wake to correspondingly increase the time-mean velocity of the wake and decrease the turbulent velocity fluctuations of the wake; reduction of both propagating broad band and tonal acoustic components of noise produced by interaction of the blade wake with a turbomachine component downstream of the rotating blade is achieved with this suction technique. Blowing and suction techniques are also provided in the invention for reducing noise associated with the wake produced by fluid flow around a stationary blade upstream of a rotating turbomachine.

  15. Infinitary Combinatory Reduction Systems

    DEFF Research Database (Denmark)

    Ketema, Jeroen; Simonsen, Jakob Grue

    2011-01-01

    We define infinitary Combinatory Reduction Systems (iCRSs), thus providing the first notion of infinitary higher-order rewriting. The systems defined are sufficiently general that ordinary infinitary term rewriting and infinitary ¿-calculus are special cases. Furthermore,we generalise a number...... of knownresults fromfirst-order infinitary rewriting and infinitary ¿-calculus to iCRSs. In particular, for fully-extended, left-linear iCRSs we prove the well-known compression property, and for orthogonal iCRSs we prove that (1) if a set of redexes U has a complete development, then all complete developments...

  16. Oxygen Reduction on Platinum

    DEFF Research Database (Denmark)

    Nesselberger, Markus

    This thesis investigates the electro reduction of oxygen on platinum nanoparticles, which serve as catalyst in low temperature fuel cells. Kinetic studies on model catalysts as well as commercially used systems are presented in order to investigate the particle size effect, the particle proximity...... carbon (HSAC) supported Pt nanoparticle (Pt/C) catalysts (of various size between 1 and 5 nm). The difference in SA between the individual Pt/C catalysts (1 to 5 nm) is very small and within the error of the measurements. The factor four of loss in SA when comparing platinum bulk and Pt/C can largely...

  17. Reduction operators of Burgers equation.

    Science.gov (United States)

    Pocheketa, Oleksandr A; Popovych, Roman O

    2013-02-01

    The solution of the problem on reduction operators and nonclassical reductions of the Burgers equation is systematically treated and completed. A new proof of the theorem on the special "no-go" case of regular reduction operators is presented, and the representation of the coefficients of operators in terms of solutions of the initial equation is constructed for this case. All possible nonclassical reductions of the Burgers equation to single ordinary differential equations are exhaustively described. Any Lie reduction of the Burgers equation proves to be equivalent via the Hopf-Cole transformation to a parameterized family of Lie reductions of the linear heat equation.

  18. Microbial reduction of iodate

    Science.gov (United States)

    Councell, T.B.; Landa, E.R.; Lovley, D.R.

    1997-01-01

    The different oxidation species of iodine have markedly different sorption properties. Hence, changes in iodine redox states can greatly affect the mobility of iodine in the environment. Although a major microbial role has been suggested in the past to account for these redox changes, little has been done to elucidate the responsible microorganisms or the mechanisms involved. In the work presented here, direct microbial reduction of iodate was demonstrated with anaerobic cell suspensions of the sulfate reducing bacterium Desulfovibrio desulfuricans which reduced 96% of an initial 100 ??M iodate to iodide at pH 7 in 30 mM NaHCO3 buffer, whereas anaerobic cell suspensions of the dissimilatory Fe(III)-reducing bacterium Shewanella putrefaciens were unable to reduce iodate in 30 mM NaHCO3 buffer (pH 7). Both D. desulfuricans and S. putrefaciens were able to reduce iodate at pH 7 in 10 mM HEPES buffer. Both soluble ferrous iron and sulfide, as well as iron monosulfide (FeS) were shown to abiologically reduce iodate to iodide. These results indicate that ferric iron and/or sulfate reducing bacteria are capable of mediating both direct, enzymatic, as well as abiotic reduction of iodate in natural anaerobic environments. These microbially mediated reactions may be important factors in the fate and transport of 129I in natural systems.

  19. Islam and harm reduction.

    Science.gov (United States)

    Kamarulzaman, A; Saifuddeen, S M

    2010-03-01

    Although drugs are haram and therefore prohibited in Islam, illicit drug use is widespread in many Islamic countries throughout the world. In the last several years increased prevalence of this problem has been observed in many of these countries which has in turn led to increasing injecting drug use driven HIV/AIDS epidemic across the Islamic world. Whilst some countries have recently responded to the threat through the implementation of harm reduction programmes, many others have been slow to respond. In Islam, The Quran and the Prophetic traditions or the Sunnah are the central sources of references for the laws and principles that guide the Muslims' way of life and by which policies and guidelines for responses including that of contemporary social and health problems can be derived. The preservation and protection of the dignity of man, and steering mankind away from harm and destruction are central to the teachings of Islam. When viewed through the Islamic principles of the preservation and protection of the faith, life, intellect, progeny and wealth, harm reduction programmes are permissible and in fact provide a practical solution to a problem that could result in far greater damage to the society at large if left unaddressed.

  20. Sonoassisted microbial reduction of chromium.

    Science.gov (United States)

    Kathiravan, Mathur Nadarajan; Karthick, Ramalingam; Muthu, Naggapan; Muthukumar, Karuppan; Velan, Manickam

    2010-04-01

    This study presents sonoassisted microbial reduction of hexavalent chromium (Cr(VI)) using Bacillus sp. isolated from tannery effluent contaminated site. The experiments were carried out with free cells in the presence and absence of ultrasound. The optimum pH and temperature for the reduction of Cr(VI) by Bacillus sp. were found to be 7.0 and 37 degrees C, respectively. The Cr(VI) reduction was significantly influenced by the electron donors and among the various electron donors studied, glucose offered maximum reduction. The ultrasound-irradiated reduction of Cr(VI) with Bacillus sp. showed efficient Cr(VI) reduction. The percent reduction was found to increase with an increase in biomass concentration and decrease with an increase in initial concentration. The changes in the functional groups of Bacillus sp., before and after chromium reduction were observed with FTIR spectra. Microbial growth was described with Monod and Andrews model and best fit was observed with Andrews model.

  1. Consumer's Guide to Radon Reduction

    Science.gov (United States)

    ... Radon Share Facebook Twitter Google+ Pinterest Contact Us Consumer's Guide to Radon Reduction: How to Fix Your ... See EPA’s About PDF page to learn more. Consumer's Guide to Radon Reduction: How to Fix Your ...

  2. Multiple gas reduction strategy

    Energy Technology Data Exchange (ETDEWEB)

    A. Kurosawa [Institute of Applied Energy, Tokyo (Japan)

    2003-07-01

    Future global warming has a close relationship with the abatement potential of six greenhouse gases (GHGs), including carbon dioxide (CO{sub 2}), methane (CH{sub 4}), nitrous oxide (N{sub 2}O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6). Therefore, multiple gas reduction flexibility should be assessed. The emission of each non-CO{sub 2} GHG is calculated endogenously by the sum of the product of the emission factor and the endogenous activity index using an integrated assessment model, GRAPE (Global Relationship Assessment to Protect the Environment). The model consists of five modules dealing with issues on energy, climate, land use, macroeconomics and environmental impacts. The uncertainty in the non-CO{sub 2} GHG emission inventory and emission factors is discussed. 5 refs., 3 figs., 1 tab.

  3. Testing the reduction rule

    CERN Document Server

    Hegerfeldt, G C

    2011-01-01

    The reduction rule, also known as the projection postulate, specifies the state after an ideal measurement. There are two forms, the original rule of von Neumann and a nowadays mostly used modification thereof due to L\\"uders, but sometimes also attributed to von Neumann. However, which form applies depends on the details of the measuring apparatus. Here we therefore consider the following problem: Given an ensemble of systems in an unknown pure or mixed state, an observable $\\hat A$ and an apparatus which performs a measurement of $\\hat A$ on the ensemble, but whose detailed working is unknown ('black box'), how can one test whether the apparatus performs a L\\"uders or von Neumann measurement?

  4. Reducts of Ramsey structures

    CERN Document Server

    Bodirsky, Manuel

    2011-01-01

    One way of studying a relational structure is to investigate functions which are related to that structure and which leave certain aspects of the structure invariant. Examples are the automorphism group, the self-embedding monoid, the endomorphism monoid, or the polymorphism clone of a structure. Such functions can be particularly well understood when the relational structure is countably infinite and has a first-order definition in another relational structure which has a finite language, is totally ordered and homogeneous, and has the Ramsey property. This is because in this situation, Ramsey theory provides the combinatorial tool for analyzing these functions -- in a certain sense, it allows to represent such functions by functions on finite sets. This is a survey of results in model theory and theoretical computer science obtained recently by the authors in this context. In model theory, we approach the problem of classifying the reducts of countably infinite ordered homogeneous Ramsey structures in a fin...

  5. Dose Reduction Techniques

    Energy Technology Data Exchange (ETDEWEB)

    WAGGONER, L.O.

    2000-05-16

    As radiation safety specialists, one of the things we are required to do is evaluate tools, equipment, materials and work practices and decide whether the use of these products or work practices will reduce radiation dose or risk to the environment. There is a tendency for many workers that work with radioactive material to accomplish radiological work the same way they have always done it rather than look for new technology or change their work practices. New technology is being developed all the time that can make radiological work easier and result in less radiation dose to the worker or reduce the possibility that contamination will be spread to the environment. As we discuss the various tools and techniques that reduce radiation dose, keep in mind that the radiological controls should be reasonable. We can not always get the dose to zero, so we must try to accomplish the work efficiently and cost-effectively. There are times we may have to accept there is only so much you can do. The goal is to do the smart things that protect the worker but do not hinder him while the task is being accomplished. In addition, we should not demand that large amounts of money be spent for equipment that has marginal value in order to save a few millirem. We have broken the handout into sections that should simplify the presentation. Time, distance, shielding, and source reduction are methods used to reduce dose and are covered in Part I on work execution. We then look at operational considerations, radiological design parameters, and discuss the characteristics of personnel who deal with ALARA. This handout should give you an overview of what it takes to have an effective dose reduction program.

  6. Alcohol harm reduction in Europe

    DEFF Research Database (Denmark)

    Herring, Rachel; Betsy, Thom; Beccaria, Franca

    2010-01-01

    The EMCDDA’s 10th scientific monograph, entitled Harm reduction: evidence, impacts and challenges provides a comprehensive overview of the harm reduction field. Part I of the monograph looks back at the emergence of harm reduction approaches and their diffusion, and explores the concept from diff...

  7. Abstract models of transfinite reductions

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2010-01-01

    We investigate transfinite reductions in abstract reduction systems. To this end, we study two abstract models for transfinite reductions: a metric model generalising the usual metric approach to infinitary term rewriting and a novel partial order model. For both models we distinguish between...

  8. A twofold interpenetrating three-dimensional Cd(II) coordination framework: poly[[μ2-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene](μ3-5-nitrobenzene-1,3-dicarboxylato)cadmium(II)].

    Science.gov (United States)

    Li, Le; Tao, Jian Qing

    2014-12-01

    A twofold interpenetrating three-dimensional Cd(II) coordination framework, [Cd(C8H3NO6)(C14H14N4)]n, has been prepared and characterized by IR spectroscopy, elemental analysis, thermal analysis and single-crystal X-ray diffraction. The asymmetric unit consists of a divalent Cd(II) atom, one 1,3-bis(2-methyl-1H-imidazol-1-yl)benzene (1,3-BMIB) ligand and one fully deprotonated 5-nitrobenzene-1,3-dicarboxylate (NO2-BDC(2-)) ligand. The coordination sphere of the Cd(II) atom consists of five O-donor atoms from three different NO2-BDC(2-) ligands and two imidazole N-donor atoms from two different 1,3-BMIB ligands, forming a distorted {CdN2O5} pentagonal bipyramid. The NO2-BDC ligand links three Cd(II) atoms via a μ1-η(1):η(1) chelating mode and a μ2-η(2):η(1) bridging mode. The title compound is a twofold interpenetrating 3,5-connected network with the {4(2).6(5).8(3)}{4(2).6} topology. In addition, the compound exhibits fluorescence emissions in the solid state at room temperature.

  9. Síntese do cerato de bário pelo método de complexação combinando EDTA-citrato e avaliação catalítica na oxidação do monóxido de carbono testada em reator de leito fixo

    Directory of Open Access Journals (Sweden)

    M. F. Lobato

    Full Text Available Resumo A perovskita de cerato de bário foi sintetizada com base no método de complexação combinando EDTA-citrato e suas propriedades catalíticas testadas na reação de oxidação do monóxido de carbono em um reator de leito fixo variando a vazão de alimentação (50 e 100 mL.min-1 e a temperatura (100 a 550 °C. A fase cristalina de interesse foi obtida com tamanho de cristalito de 133 nm, junto com uma pequena quantidade de BaCO3 (3%. Quando sintetizado pelo método de complexação combinando EDTA-citrato, o cerato de bário apresenta um formato esférico irregular com aglomerados de diferentes tamanhos e com a presença de poros de diferentes tamanhos distribuídos aleatoriamente, sendo sua área superficial específica igual a 2,61 m2.g-1. Na vazão de 50 mL.min-1 ocorreu maior conversão quando comparado com a de 100 mL.min-1, sendo mais evidente entre 300 e 400 °C. Além disso, na vazão de 50 mL.min-1 ocorreu conversão total de CO em CO2 a 400 °C, enquanto que em 100 mL.min-1 a conversão foi de aproximadamente 60%. Com o uso da perovskita como catalisador o processo de oxidação é completo a 400 °C, enquanto que na reação sem catalisador a conversão completa é alcançada somente a 550 °C. Apesar da sua pequena área superficial, o BaCeO3 é altamente reativo na oxidação do monóxido de carbono.

  10. Heart Failure Readmission Reduction.

    Science.gov (United States)

    Drozda, Joseph P; Smith, Donna A; Freiman, Paul C; Pursley, Janet; VanSlette, Jeffrey A; Smith, Timothy R

    Little is known regarding effectiveness of readmission reduction programs over time. The Heart Failure Management Program (HFMP) of St. John's Physician Group Practice (PGP) Demonstration provided an opportunity to assess outcomes over an extended period. Data from an electronic health record, an inpatient database, a disease registry, and the Social Security Death Master File were analyzed for patients admitted with heart failure (HF) for 5 years before (Period 1) and 5 years after (Period 2) inception of PGP. HF admissions decreased (Period 1, 58.3/month; Period 2, 52.4/month, P = .007). Thirty-day all-cause readmission rate dropped from Period 1 (annual average 18.8% [668/3545]) to year 1 of Period 2 (16.9% [136/804], P = .04) and remained stable thereafter (annual average 16.8% [589/3503]). Thirty-day mortality rate was flat throughout. HFMP was associated with decreased readmissions, primarily related to outpatient case management, while mortality remained stable.

  11. Electrochemical reduction of NOx

    DEFF Research Database (Denmark)

    Traulsen, Marie Lund

    NO and NO2 (collectively referred to as NOx) are air pollutants, and the largest single contributor to NOx pollution is automotive exhaust. This study investigates electrochemical deNOx, a technology which aims to remove NOx from automotive diesel exhaust by electrochemical reduction of NOx to N2...... and O2. The focus in this study is on improving the activity and selectivity of solid oxide electrodes for electrochemical deNOx by addition of NOx storage compounds to the electrodes. Two different composite electrodes, La0.85Sr0.15MnO3-δ-Ce0.9Gd0.1O1.95 (LSM15-CGO10) and La0.85Sr0.15FeO3-δ-Ce0.9Gd0.1O......1.95 (LSF15-CGO10), have been investigated in combination with three different NOx storage compounds: BaO, K2O and MnOx. The main focus in the investigation has been on conversion measurements and electrochemical characterization, the latter by means of electrochemical impedance spectroscopy...

  12. Setting goals for drug policy: harm reduction or use reduction?

    Science.gov (United States)

    Caulkins, J P; Reuter, P

    1997-09-01

    Historically, United States drug policy has focused on use reduction; harm reduction is a prominent alternative. This paper aims to provoke and inform more debate about the relative merits of these two. Since harm is not necessarily proportional to use, use reduction and harm reduction differ. Both terms are somewhat ambiguous; precisely defining them clarifies thinking and policy implications. Measures associated with use reduction goals are poor; those associated with harm reduction are even worse. National goals influence the many decentralized individuals who collectively make drug policy; clearly enunciating goals makes some policy choices transparent and goals serve a variety of purposes besides guiding programmatic decisions. We recommend that the overall objective be to minimize the total harm associated with drug production, distribution, consumption and control. Reducing use should be seen as a principal means of attaining that end.

  13. Photo-induced CO2 reduction by CH4/H2O to fuels over Cu-modified g-C3N4 nanorods under simulated solar energy

    Science.gov (United States)

    Tahir, Beenish; Tahir, Muhammad; Amin, Nor Aishah Saidina

    2017-10-01

    Copper modified polymeric graphitic carbon nitride (Cu/g-C3N4) nanorods for photo-induced CO2 conversion with methane (CH4) and water (H2O) as reducing system under simulated solar energy has been investigated. The nanocatalysts, synthesized by pyrolysis and sonication, were characterized by XRD, FTIR, Raman analysis, XPS, SEM, N2 adsorption-desorption and PL spectroscopy. The presence of Cu2+ ions over the g-C3N4 structure inhibited charge carriers recombination process. The results indicated that photo-activity and selectivity of Cu/g-C3N4 photo-catalyst for CO2 reduction greatly dependent on the type of CO2-reduction system. CO2 was efficiently converted to CH4 and CH3OH with traces of C2H4 and C2H6 hydrocarbons in the CO2-water system. The yield of the main product, CH4 over 3 wt.% Cu/g-C3N4 was 109 μmole g-cata.-1 h-1 under visible light irradiation, significantly higher than the pure g-C3N4 catalyst (60 μmole/g.cat). In photo-induced CO2-CH4 reaction, CO and H2 were detected as the main products with smaller amount of hydrocarbons. The highest efficiency was detected over 3 wt.%Cu-loading of g-C3N4 and at optimal CH4/CO2 feed ratio of 1.0. The maximum yield of CO and H2 detected were 142 and 76 μmole g-catal.-1 h-1, respectively at selectivity 66.6% and 32.5%, respectively. Significantly enhanced CO2/CH4 reduction over Cu/g-C3N4 was attributed to its polymeric structure with efficient charge transfer property and inhibited charges recombination rate. A proposed photo-induced reaction mechanism, corroborated with the experimental data, was also deliberated.

  14. Deliberating emission reduction options

    Energy Technology Data Exchange (ETDEWEB)

    Dowd, A.M.; Rodriguez, M.; Jeanneret, T. [Commonwealth Scientific and Industrial Research Organisation CSIRO, 37 Graham Rd, Highett VIC 3190 (Australia); De Best-Waldhober, M.; Straver, K.; Mastop, J.; Paukovic, M. [Energy research Centre of the Netherlands ECN, Policy Studies, Amsterdam (Netherlands)

    2012-06-15

    For more than 20 years there has been a concerted international effort toward addressing climate change. International conventions, such as the United Nations Foreign Convention on Climate Change (UNFCCC; ratified in 1994), have been established by committed nations seeking to address global climate change through the reduction of greenhouse gases emitted into the Earth's atmosphere (Global CCS Institute, 2011). Long recognised as the most crucial of the greenhouse gases to impact global warming, the majority of carbon dioxide's anthropogenic global emissions are directly related to fuel combustion of which both Australia and the Netherlands' energy production is significantly reliant. Both these nations will need to consider many opinions and make hard decisions if alternative energy options are to be implemented at the scale that is required to meet international emission targets. The decisions that are required not only need to consider the many options available but also their consequences. Along with politicians, policy developers and industry, the general public also need to be active participants in deciding which energy options, and their subsequent consequences, are acceptable for implementation at the national level. Access to balanced and factual information is essential in establishing informed opinions on the many policy options available. Past research has used several methods to measure public perceptions and opinions yet for complex issues, such as emission reduction, some of these methods have shown to be problematic. For example, semi structured interviews can provide data that is flexible and context rich yet is does also come with the limitations such as it seldom provides a practical assessment that can be utilised from researcher to researcher, across disciplines and public participation techniques. Surveys on the other hand usually address these limitations but surveys that do not encourage comparison of information or ask

  15. Robust methods for data reduction

    CERN Document Server

    Farcomeni, Alessio

    2015-01-01

    Robust Methods for Data Reduction gives a non-technical overview of robust data reduction techniques, encouraging the use of these important and useful methods in practical applications. The main areas covered include principal components analysis, sparse principal component analysis, canonical correlation analysis, factor analysis, clustering, double clustering, and discriminant analysis.The first part of the book illustrates how dimension reduction techniques synthesize available information by reducing the dimensionality of the data. The second part focuses on cluster and discriminant analy

  16. Turbulent drag reduction by polymers

    Energy Technology Data Exchange (ETDEWEB)

    Bonn, Daniel [Van der Waals-Zeeman Instituut, University of Amsterdam, Valckenierstraat 65 1018, XE Amsterdam (Netherlands); Amarouchene, Yacine [CPMOH, Universite Bordeaux 1, 351 Cours de la Liberation, 33405 Talence cedex (France); Wagner, Christian [Institut fuer Experimentalphysik, Universitaet des Saarlandes, Saarbruecken (Germany); Douady, Stephane [Laboratoire de Physique Statistique de l' ENS, 24 rue Lhomond, 75231 Paris cedex 05 (France); Cadot, Olivier [ENSTA, Chemin de la Huniere, 91761 Palaiseau cedex (France)

    2005-04-13

    The reduction of turbulent energy dissipation by addition of polymers is studied experimentally. We first address the question of where the action of the polymers is taking place. Subsequently, we show that there is a direct correlation of drag reduction with the elongational viscosity of the polymers. For this, the reduction of turbulent energy dissipation by addition of the biopolymer DNA is studied. These results open the way for a direct visualization study of the polymer conformation in a turbulent boundary layer.

  17. Routh reduction and Cartan mechanics

    Science.gov (United States)

    Capriotti, S.

    2017-04-01

    In the present work a Cartan mechanics version for Routh reduction is considered, as an intermediate step towards Routh reduction in field theory. Motivation for this generalization comes from a scheme for integrable systems (Fehér and Gábor, 2002), used for understanding the occurrence of Toda field theories in so called Hamiltonian reduction of WZNW field theories (Fehér et al., 1992). As a way to accomplish with this intermediate aim, this article also contains a formulation of the Lagrangian Adler-Kostant-Symes systems discussed in Fehér and Gábor (2002) in terms of Routh reduction.

  18. Casting light on harm reduction

    DEFF Research Database (Denmark)

    Jourdan, Michael

    2009-01-01

    reduction in its more comprehensive forms continuously stir up controversy. In spite of this the notion of complementarity is commonly upheld leaving opposition to harm reduction inexplicable and non-researchable. Methods: Teaching experience in multiple settings in which opposing views have surfaced...

  19. Reduction-Fired Seedpod Bowls.

    Science.gov (United States)

    Beyke, Rod

    2001-01-01

    Focuses on a reduction-firing process with an aim of producing high-quality blackware similar to the black-on-black pottery of Maria Martinez and other American Indian potters. Includes a lesson on creating reduction-fired seedpod bowls, lists of instructional resources and materials, and the objectives and evaluation. (CMK)

  20. Chronic sleep reduction in adolescents

    NARCIS (Netherlands)

    Dewald-Kaufmann, J.F.

    2012-01-01

    Based on the results of this thesis, it can be concluded that sleep problems and chronic sleep reduction have a high impact on adolescents’ daytime functioning. Additionally, this research shows that gradual sleep extension can improve adolescents’ sleep and especially their chronic sleep reduction.

  1. Reduction of chemical reaction models

    Science.gov (United States)

    Frenklach, Michael

    1991-01-01

    An attempt is made to reconcile the different terminologies pertaining to reduction of chemical reaction models. The approaches considered include global modeling, response modeling, detailed reduction, chemical lumping, and statistical lumping. The advantages and drawbacks of each of these methods are pointed out.

  2. Synchrotron Based Structural Investigations of Mass-Selected PtxGd Nanoparticles and a Gd/Pt(111) Single Crystal for Electrochemical Oxygen Reduction

    DEFF Research Database (Denmark)

    Pedersen, Anders Filsøe; Velazquez-Palenzuela, Amado Andres; Masini, Federico

    2015-01-01

    . 134, 16476–16479 (2012). 3. Velazquez-Palenzuela, A. et al. The enhanced activity of mass-selected PtxGd nanoparticles for oxygen electroreduction. J. Catal. [in press] (2015). doi:10.1016/j.jcat.2014.12.012 4. Perez-Alonso, F. J. et al. The Effect of Size on the Oxygen Electroreduction Activity...

  3. ACID- AND BASE-CATALIZED HYDROLYSES OF CORN STALK

    Directory of Open Access Journals (Sweden)

    Cristina Sánchez

    2011-04-01

    Full Text Available Nowadays agricultural wastes represent an alternative source of renewable raw materials. Different processes can be applied to these alternative materials to separate their components and obtain chemical products with high added value, such as bioethanol, organic acids, monomers, and biopolymers. The main objective of this work is to study the extraction of hemicelluloses from corn stalks using different reagents [H2SO4, HNO3, HCL, CH3COOH, CF3COOH, Ca(OH2, NaOH]. The raw material was characterized and fractionated with autoclave hydrolysis processes (121 ºC, 1:20 solid/liquid ratio, 60 min, pH = 4 or 8. Monomeric sugars concentration, TDS, MO, MI, density, and final pH of the hydrolysate were determined. Hemicelluloses were precipitated and analyzed by different techniques (FTIR, TGA and GPC. The highest yield of hemicelluloses extraction was achieved by sulphuric acid (0.98 g/L total sugar content and the less effective reagent was Ca(OH2 (0.52 g/L total sugar content.

  4. Acute IPPS - Readmissions Reduction Program

    Data.gov (United States)

    U.S. Department of Health & Human Services — Section 3025 of the Affordable Care Act added section 1886(q) to the Social Security Act establishing the Hospital Readmissions Reduction Program, which requires CMS...

  5. Model Reduction of Hybrid Systems

    DEFF Research Database (Denmark)

    Shaker, Hamid Reza

    systems are derived in this thesis. The results are used for output feedback control of switched nonlinear systems. Model reduction of piecewise affine systems is also studied in this thesis. The proposed method is based on the reduction of linear subsystems inside the polytopes. The methods which......High-Technological solutions of today are characterized by complex dynamical models. A lot of these models have inherent hybrid/switching structure. Hybrid/switched systems are powerful models for distributed embedded systems design where discrete controls are applied to continuous processes...... of hybrid systems, designing controllers and implementations is very high so that the use of these models is limited in applications where the size of the state space is large. To cope with complexity, model reduction is a powerful technique. This thesis presents methods for model reduction and stability...

  6. Fermion masses from dimensional reduction

    Energy Technology Data Exchange (ETDEWEB)

    Kapetanakis, D. (National Research Centre for the Physical Sciences Democritos, Athens (Greece)); Zoupanos, G. (European Organization for Nuclear Research, Geneva (Switzerland))

    1990-10-11

    We consider the fermion masses in gauge theories obtained from ten dimensions through dimensional reduction on coset spaces. We calculate the general fermion mass matrix and we apply the mass formula in illustrative examples. (orig.).

  7. Approximate reduction of dynamical systems

    CERN Document Server

    Tabuada, Paulo; Julius, Agung; Pappas, George J

    2007-01-01

    The reduction of dynamical systems has a rich history, with many important applications related to stability, control and verification. Reduction of nonlinear systems is typically performed in an exact manner - as is the case with mechanical systems with symmetry--which, unfortunately, limits the type of systems to which it can be applied. The goal of this paper is to consider a more general form of reduction, termed approximate reduction, in order to extend the class of systems that can be reduced. Using notions related to incremental stability, we give conditions on when a dynamical system can be projected to a lower dimensional space while providing hard bounds on the induced errors, i.e., when it is behaviorally similar to a dynamical system on a lower dimensional space. These concepts are illustrated on a series of examples.

  8. Transitive Reduction of Citation Networks

    CERN Document Server

    Clough, James R; Loach, Tamar V; Evans, Tim S

    2013-01-01

    Citation networks form directed acyclic graphs. The transitive reduction of such a DAG removes all edges in the graph that are implied by transitivity, but retains the causal structure of the original network. We investigate how the degree distribution, clustering coefficients and relationship between time of publication and degree (representing citation count) are changed under transitive reduction. We show that models which accurately reproduce the degree distribution of a citation network before transitive reduction may not do so afterwards and hence suggest that these models fail to accurately capture the causal structure of the network. We also investigate how the citation count of individual papers is changed and suggest that information about the types of citations a paper receives can be inferred from the number of citations which are retained after transitive reduction. These methods are tested on citation networks from the hep-th and hep-ph sections of the arXiv repository, and all data has been mad...

  9. Logistics Reduction and Repurposing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Advanced Exploration Systems (AES) Logistics Reduction and Repurposing (LRR) project will enable a mission-independent cradle-to-grave-to-cradle...

  10. The relaxation & stress reduction workbook

    National Research Council Canada - National Science Library

    Davis, Martha; Eshelman, Elizabeth Robbins; McKay, Matthew

    2008-01-01

    "The Relaxation & Stress Reduction Workbook broke new ground when it was first published in 1980, detailing easy, step-by-step techniques for calming the body and mind in an increasingly overstimulated world...

  11. Chemical model reduction under uncertainty

    KAUST Repository

    Najm, Habib

    2016-01-05

    We outline a strategy for chemical kinetic model reduction under uncertainty. We present highlights of our existing deterministic model reduction strategy, and describe the extension of the formulation to include parametric uncertainty in the detailed mechanism. We discuss the utility of this construction, as applied to hydrocarbon fuel-air kinetics, and the associated use of uncertainty-aware measures of error between predictions from detailed and simplified models.

  12. 2dfdr: Data reduction software

    Science.gov (United States)

    AAO software Team

    2015-05-01

    2dfdr is an automatic data reduction pipeline dedicated to reducing multi-fibre spectroscopy data, with current implementations for AAOmega (fed by the 2dF, KOALA-IFU, SAMI Multi-IFU or older SPIRAL front-ends), HERMES, 2dF (spectrograph), 6dF, and FMOS. A graphical user interface is provided to control data reduction and allow inspection of the reduced spectra.

  13. [Substances considered addictive: prohibition, harm reduction and risk reduction].

    Science.gov (United States)

    Menéndez, Eduardo

    2012-01-01

    Latin America is currently the region with the highest rate of homicides worldwide, and a large part of the killings are linked to so-called organized crime, especially drug trafficking. The trafficking of drugs is a consequence of the illegality of certain substances which - at least presently - is based in and legitimated by biomedical criteria that turns the production, commercialization and often the consumption of certain substances considered addictive into "offenses against health." This text briefly analyzes the two policies formulated and implemented thus far in terms of prohibition and harm reduction, considering the failure of prohibitionism as well as the limitations of harm reduction proposals. The constant and multiple inconsistencies and contradictions of prohibitionism are noted, indicating the necessity of regarding cautiously repeated comments about its "failure." The text proposes the implementation of a policy of risk reduction that includes not only the behavior of individuals and groups, but also the structural dimension, both in economic-political and cultural terms.

  14. State of the direct reduction and reduction smelting processes

    Directory of Open Access Journals (Sweden)

    Markotić A.

    2002-01-01

    Full Text Available For quite a long time efforts have been made to develop processes for producing iron i.e. steel without employing conventional procedures - from ore, coke, blast furnace, iron, electric arc furnace, converter to steel. The insufficient availability and the high price of the coking coals have forced many countries to research and adopt the non-coke-consuming reduction and metal manufacturing processes (non-coke metallurgy, direct reduction, direct processes. This paper represents a survey of the most relevant processes from this domain by the end of 2000, which display a constant increase in the modern process metallurgy.

  15. Unfavourable results following reduction mammoplasty

    Directory of Open Access Journals (Sweden)

    Lakshmi Saleem

    2013-01-01

    Full Text Available Breast reduction is a common cosmetic surgical procedure. It aims not only at bringing down the size of the breast proportionate to the build of the individual, but also to overcome the discomfort caused by massive, ill-shaped and hanging breasts. The operative procedure has evolved from mere reduction of breast mass to enhanced aesthetic appeal with a minimum of scar load. The selection of technique needs to be individualised. Bilateral breast reduction is done most often. Haematoma, seroma, fat necrosis, skin loss, nipple loss and unsightly, painful scars can be the complications of any procedure on the breast. These may result from errors in judgement, wrong surgical plan and imprecise execution of the plan. Though a surfeit of studies are available on breast reduction, very few dwell upon its complications. The following article is a distillation of three decades of experience of the senior author (L.S. in reduction mammoplasty. An effort is made to understand the reasons for unfavourable results. To conclude, most complications can be overcome with proper selection of procedure for the given patient and with gentle tissue handling.

  16. Kloosterman sheaves for reductive groups

    CERN Document Server

    Heinloth, Jochen; Yun, Zhiwei

    2010-01-01

    Deligne constructed a remarkable local system on $\\bP^1-\\{0,\\infty\\}$ attached to a family of Kloosterman sums. Katz calculated its monodromy and asked whether there are Kloosterman sheaves for general reductive groups and which automorphic forms should be attached to these local systems under the Langlands correspondence. Motivated by work of Gross and Frenkel-Gross we find an explicit family of such automorphic forms and even a simple family of automorphic sheaves in the framework of the geometric Langlands program. We use these automorphic sheaves to construct l-adic Kloosterman sheaves for any reductive group in a uniform way, and describe the local and global monodromy of these Kloosterman sheaves. In particular, they give motivic Galois representations with exceptional monodromy groups G_2,F_4,E_7 and E_8. This also gives an example of the geometric Langlands correspondence with wild ramifications for any reductive group.

  17. Microbial reduction of iron ore

    Science.gov (United States)

    Hoffmann, Michael R.; Arnold, Robert G.; Stephanopoulos, Gregory

    1989-01-01

    A process is provided for reducing iron ore by treatment with microorganisms which comprises forming an aqueous mixture of iron ore, microorganisms operable for reducing the ferric iron of the iron ore to ferrous iron, and a substrate operable as an energy source for the microbial reduction; and maintaining the aqueous mixture for a period of time and under conditions operable to effect the reduction of the ore. Preferably the microorganism is Pseudomonas sp. 200 and the reduction conducted anaerobically with a domestic wastewater as the substrate. An aqueous solution containing soluble ferrous iron can be separated from the reacted mixture, treated with a base to precipitate ferrous hydroxide which can then be recovered as a concentrated slurry.

  18. Model reduction of parametrized systems

    CERN Document Server

    Ohlberger, Mario; Patera, Anthony; Rozza, Gianluigi; Urban, Karsten

    2017-01-01

    The special volume offers a global guide to new concepts and approaches concerning the following topics: reduced basis methods, proper orthogonal decomposition, proper generalized decomposition, approximation theory related to model reduction, learning theory and compressed sensing, stochastic and high-dimensional problems, system-theoretic methods, nonlinear model reduction, reduction of coupled problems/multiphysics, optimization and optimal control, state estimation and control, reduced order models and domain decomposition methods, Krylov-subspace and interpolatory methods, and applications to real industrial and complex problems. The book represents the state of the art in the development of reduced order methods. It contains contributions from internationally respected experts, guaranteeing a wide range of expertise and topics. Further, it reflects an important effor t, carried out over the last 12 years, to build a growing research community in this field. Though not a textbook, some of the chapters ca...

  19. Uranium isotopes fingerprint biotic reduction

    Science.gov (United States)

    Stylo, Malgorzata; Neubert, Nadja; Wang, Yuheng; Monga, Nikhil; Romaniello, Stephen J.; Weyer, Stefan; Bernier-Latmani, Rizlan

    2015-01-01

    Knowledge of paleo-redox conditions in the Earth’s history provides a window into events that shaped the evolution of life on our planet. The role of microbial activity in paleo-redox processes remains unexplored due to the inability to discriminate biotic from abiotic redox transformations in the rock record. The ability to deconvolute these two processes would provide a means to identify environmental niches in which microbial activity was prevalent at a specific time in paleo-history and to correlate specific biogeochemical events with the corresponding microbial metabolism. Here, we demonstrate that the isotopic signature associated with microbial reduction of hexavalent uranium (U), i.e., the accumulation of the heavy isotope in the U(IV) phase, is readily distinguishable from that generated by abiotic uranium reduction in laboratory experiments. Thus, isotope signatures preserved in the geologic record through the reductive precipitation of uranium may provide the sought-after tool to probe for biotic processes. Because uranium is a common element in the Earth’s crust and a wide variety of metabolic groups of microorganisms catalyze the biological reduction of U(VI), this tool is applicable to a multiplicity of geological epochs and terrestrial environments. The findings of this study indicate that biological activity contributed to the formation of many authigenic U deposits, including sandstone U deposits of various ages, as well as modern, Cretaceous, and Archean black shales. Additionally, engineered bioremediation activities also exhibit a biotic signature, suggesting that, although multiple pathways may be involved in the reduction, direct enzymatic reduction contributes substantially to the immobilization of uranium. PMID:25902522

  20. NEC-2020 emission reduction scenarios

    DEFF Research Database (Denmark)

    Slentø, Erik; Nielsen, Ole-Kenneth; Hoffmann, Leif

    The upcoming NEC-2020 EU directive sets up emission ceilings for NOX, SO2, NH3, NMVOC and PM in order to meet the environmental exposure targets of the Thematic Strategy. This report contains an assessment of intermediary emission reduction scenarios for Denmark, computed by the GAINS model 2007......, which serves as the basis for the pending negotiations in EU. The assessment is brought up to date by including a brief evaluation of the new reduction scenarios published in 2008, founding the European Commission NEC-2020 directive proposal....

  1. Complexity reduction of astrochemical networks

    CERN Document Server

    Grassi, T; Gianturco, F A; Baiocchi, P; Merlin, E

    2012-01-01

    We present a new computational scheme aimed at reducing the complexity of the chemical networks in astrophysical models, one which is shown to markedly improve their computational efficiency. It contains a flux-reduction scheme that permits to deal with both large and small systems. This procedure is shown to yield a large speed-up of the corresponding numerical codes and provides good accord with the full network results. We analyse and discuss two examples involving chemistry networks of the interstellar medium and show that the results from the present reduction technique reproduce very well the results from fuller calculations.

  2. Flavin reduction activates Drosophila cryptochrome.

    Science.gov (United States)

    Vaidya, Anand T; Top, Deniz; Manahan, Craig C; Tokuda, Joshua M; Zhang, Sheng; Pollack, Lois; Young, Michael W; Crane, Brian R

    2013-12-17

    Entrainment of circadian rhythms in higher organisms relies on light-sensing proteins that communicate to cellular oscillators composed of delayed transcriptional feedback loops. The principal photoreceptor of the fly circadian clock, Drosophila cryptochrome (dCRY), contains a C-terminal tail (CTT) helix that binds beside a FAD cofactor and is essential for light signaling. Light reduces the dCRY FAD to an anionic semiquinone (ASQ) radical and increases CTT proteolytic susceptibility but does not lead to CTT chemical modification. Additional changes in proteolytic sensitivity and small-angle X-ray scattering define a conformational response of the protein to light that centers at the CTT but also involves regions remote from the flavin center. Reduction of the flavin is kinetically coupled to CTT rearrangement. Chemical reduction to either the ASQ or the fully reduced hydroquinone state produces the same conformational response as does light. The oscillator protein Timeless (TIM) contains a sequence similar to the CTT; the corresponding peptide binds dCRY in light and protects the flavin from oxidation. However, TIM mutants therein still undergo dCRY-mediated degradation. Thus, photoreduction to the ASQ releases the dCRY CTT and promotes binding to at least one region of TIM. Flavin reduction by either light or cellular reductants may be a general mechanism of CRY activation.

  3. Reduction des effectifs ou licenciements

    CERN Multimedia

    Maiani, Luciano

    2002-01-01

    "Vous faites un amalgame entre la reduction en cours des effectifs du CERN (organisation europeenne pour la recherche nucleaire) et les economies que le laboratoire doit realiser dans les cinq ans a venir pour financer le projet de grand collisionneur de hadrons (Le Monde du 4 septembre)" (1/2 page).

  4. GumTree: Data reduction

    Science.gov (United States)

    Rayner, Hugh; Hathaway, Paul; Hauser, Nick; Fei, Yang; Franceschini, Ferdi; Lam, Tony

    2006-11-01

    Access to software tools for interactive data reduction, visualisation and analysis during a neutron scattering experiment enables instrument users to make informed decisions regarding the direction and success of their experiment. ANSTO aims to enhance the experiment experience of its facility's users by integrating these data reduction tools with the instrument control interface for immediate feedback. GumTree is a software framework and application designed to support an Integrated Scientific Experimental Environment, for concurrent access to instrument control, data acquisition, visualisation and analysis software. The Data Reduction and Analysis (DRA) module is a component of the GumTree framework that allows users to perform data reduction, correction and basic analysis within GumTree while an experiment is running. It is highly integrated with GumTree, able to pull experiment data and metadata directly from the instrument control and data acquisition components. The DRA itself uses components common to all instruments at the facility, providing a consistent interface. It features familiar ISAW-based 1D and 2D plotting, an OpenGL-based 3D plotter and peak fitting performed by fityk. This paper covers the benefits of integration, the flexibility of the DRA module, ease of use for the interface and audit trail generation.

  5. Asymmetry Reduction Theory of FDI

    DEFF Research Database (Denmark)

    Li, Xin

    In this paper, I first briefly introduce Moon & Roehl’s (1993, 2001) imbalance theory of FDI, then I identify its three deficiencies that may be responsible for the relative lack of impact of the potentially powerful imbalance logic, and then I propose an asymmetry reduction theory (ARC) of FDI...

  6. Representative mass reduction in sampling

    DEFF Research Database (Denmark)

    Petersen, Lars; Esbensen, Harry Kim; Dahl, Casper Kierulf

    2004-01-01

    We here present a comprehensive survey of current mass reduction principles and hardware available in the current market. We conduct a rigorous comparison study of the performance of 17 field and/or laboratory instruments or methods which are quantitatively characterized (and ranked) for accuracy...

  7. Background reduction in cryogenic detectors

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, Daniel A.; /Fermilab

    2005-04-01

    This paper discusses the background reduction and rejection strategy of the Cryogenic Dark Matter Search (CDMS) experiment. Recent measurements of background levels from CDMS II at Soudan are presented, along with estimates for future improvements in sensitivity expected for a proposed SuperCDMS experiment at SNOLAB.

  8. APPLICATION OF RADON REDUCTION METHODS

    Science.gov (United States)

    The document is intended to aid homeowners and contractors in diagnosing and solving indoor radon problems. It will also be useful to State and Federal regulatory officials and many other persons who provide advice on the selection, design and operation of radon reduction methods...

  9. Sulfate reduction in freshwater peatlands

    Energy Technology Data Exchange (ETDEWEB)

    Oequist, M.

    1996-12-31

    This text consist of two parts: Part A is a literature review on microbial sulfate reduction with emphasis on freshwater peatlands, and part B presents the results from a study of the relative importance of sulfate reduction and methane formation for the anaerobic decomposition in a boreal peatland. The relative importance of sulfate reduction and methane production for the anaerobic decomposition was studied in a small raised bog situated in the boreal zone of southern Sweden. Depth distribution of sulfate reduction- and methane production rates were measured in peat sampled from three sites (A, B, and C) forming an minerotrophic-ombrotrophic gradient. SO{sub 4}{sup 2-} concentrations in the three profiles were of equal magnitude and ranged from 50 to 150 {mu}M. In contrast, rates of sulfate reduction were vastly different: Maximum rates in the three profiles were obtained at a depth of ca. 20 cm below the water table. In A it was 8 {mu}M h{sup -1} while in B and C they were 1 and 0.05 {mu}M h{sup -1}, respectively. Methane production rates, however, were more uniform across the three nutrient regimes. Maximum rates in A (ca. 1.5 {mu}g d{sup -1} g{sup -1}) were found 10 cm below the water table, in B (ca. 1.0 {mu}g d{sup -1} g{sup -1}) in the vicinity of the water table, and in C (0.75 {mu}g d{sup -1} g{sup -1}) 20 cm below the water table. In all profiles both sulfate reduction and methane production rates were negligible above the water table. The areal estimates of methane production for the profiles were 22.4, 9.0 and 6.4 mmol m{sup -2} d{sup -1}, while the estimates for sulfate reduction were 26.4, 2.5, and 0.1 mmol m{sup -2} d{sup -1}, respectively. The calculated turnover times at the sites were 1.2, 14.2, and 198.7 days, respectively. The study shows that sulfate reducing bacteria are important for the anaerobic degradation in the studied peatland, especially in the minerotrophic sites, while methanogenic bacteria dominate in ombrotrophic sites Examination

  10. Discovering Natural Laws by Reduction

    Institute of Scientific and Technical Information of China (English)

    吴轶华

    1989-01-01

    A polynomial algorithm.called Reduction,is presented to discover natural laws by analysing a set of experimental data.instead of a heuristic exploration which,when adopted in BACON,can only lead to rediscovering simple laws.A complex law with multiple variables involved can be discovered by reducing it to a search.This search is so efficient that it does not need any backtracking and is able to cover most of possible laws.A reduction-based discovery system,called DISCOVER 2.0,was developed with a flexible knowledge base and an ability of dealing with imperfect data.The system has been verified to be valid computationally,practically,and theoretically,by discovering a great number o complex laws,and can be also viewed as a leaming engine embodied in any intelligent systems to improve their performance by obtaining a general rule from the accumulated data.

  11. Mechanochemical reduction of copper sulfide

    DEFF Research Database (Denmark)

    Balaz, P.; Takacs, L.; Jiang, Jianzhong

    2002-01-01

    The mechanochemical reduction of copper sulfide with iron was induced in a Fritsch P-6 planetary mill, using WC vial filled with argon and WC balls. Samples milled for specific intervals were analyzed by XRD and Mossbauer spectroscopy. Most of the reaction takes place during the first 10 min...... of milling and only FeS and Cu are found after 60 min. The main chemical process is accompanied by phase transformations of the sulfide phases as a result of milling. Djurleite partially transformed to chalcocite and a tetragonal copper sulfide phase before reduction. The cubic modification of FeS was formed...... first, transforming to hexagonal during the later stages of the process. The formation of off-stoichiometric phases and the release of some elemental sulfur by copper sulfide are also probable....

  12. Random walks on reductive groups

    CERN Document Server

    Benoist, Yves

    2016-01-01

    The classical theory of Random Walks describes the asymptotic behavior of sums of independent identically distributed random real variables. This book explains the generalization of this theory to products of independent identically distributed random matrices with real coefficients. Under the assumption that the action of the matrices is semisimple – or, equivalently, that the Zariski closure of the group generated by these matrices is reductive - and under suitable moment assumptions, it is shown that the norm of the products of such random matrices satisfies a number of classical probabilistic laws. This book includes necessary background on the theory of reductive algebraic groups, probability theory and operator theory, thereby providing a modern introduction to the topic.

  13. Designing Tone Reservation PAR Reduction

    Directory of Open Access Journals (Sweden)

    Johansson Albin

    2006-01-01

    Full Text Available Tone reservation peak-to-average (PAR ratio reduction is an established area when it comes to bringing down signal peaks in multicarrier (DMT or OFDM systems. When designing such a system, some questions often arise about PAR reduction. Is it worth the effort? How much can it give? How much does it give depending on the parameter choices? With this paper, we attempt to answer these questions without resolving to extensive simulations for every system and every parameter choice. From a specification of the allowed spectrum, for instance prescribed by a standard, including a PSD-mask and a number of tones, we analytically predict achievable PAR levels, and thus implicitly suggest parameter choices. We use the ADSL2 and ADSL2+ systems as design examples.

  14. Wind load reduction for heliostats

    Energy Technology Data Exchange (ETDEWEB)

    Peterka, J.A.; Hosoya, N.; Bienkiewicz, B.; Cermak, J.E.

    1986-05-01

    This report presents the results of wind-tunnel tests supported through the Solar Energy Research Institute (SERI) by the Office of Solar Thermal Technology of the US Department of Energy as part of the SERI research effort on innovative concentrators. As gravity loads on drive mechanisms are reduced through stretched-membrane technology, the wind-load contribution of the required drive capacity increases in percentage. Reduction of wind loads can provide economy in support structure and heliostat drive. Wind-tunnel tests have been directed at finding methods to reduce wind loads on heliostats. The tests investigated primarily the mean forces, moments, and the possibility of measuring fluctuating forces in anticipation of reducing those forces. A significant increase in ability to predict heliostat wind loads and their reduction within a heliostat field was achieved.

  15. Exploring Paradigms of Crime Reduction

    DEFF Research Database (Denmark)

    Soothill, Keith; Christoffersen, Mogens N.; Hussain, Azhar

    2010-01-01

    Using Danish registers for a 1980 birth cohort of 29,944 males with parental information and following up these cases for 25 years, the study considers four paradigms of crime reduction (parental child rearing, structural factors around adolescence, locality and individual resources). Focusing...... have more widespread benefits, but the assumed causal links need to be further explored. The use of population registers, under controlled conditions, provides an important window on criminal careers....

  16. Seismic Disaster Reduction in China

    Institute of Scientific and Technical Information of China (English)

    Ministry of Construction

    2001-01-01

    @@ Great accomplishments have been made in seismic disaster reduction in China's engineering construction and city construction projects during the past decade (1990~2000). A new national map on the division of seismic intensity has been promulgated, and a series of anti-seismic standards and norms have been drafted or revised, which has further improved the country's technical code system on anti-seismic engineering measures.

  17. Sustained Low Temperature NOx Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Zha, Yuhui

    2017-04-05

    Increasing regulatory, environmental, and customer pressure in recent years led to substantial improvements in the fuel efficiency of diesel engines, including the remarkable breakthroughs demonstrated through the Super Truck program supported by the U.S. Department of Energy (DOE). On the other hand, these improvements have translated into a reduction of exhaust gas temperatures, thus further complicating the task of controlling NOx emissions, especially in low power duty cycles. The need for improved NOx conversion over these low temperature duty cycles is also observed as requirements tighten with in-use emissions testing. Sustained NOx reduction at low temperatures, especially in the 150-200oC range, shares some similarities with the more commonly discussed cold-start challenge, however poses a number of additional and distinct technical problems. In this project we set a bold target of achieving and maintaining a 90% NOx conversion at the SCR catalyst inlet temperature of 150oC. The project is intended to push the boundaries of the existing technologies, while staying within the realm of realistic future practical implementation. In order to meet the resulting challenges at the levels of catalyst fundamentals, system components, and system integration, Cummins has partnered with the DOE, Johnson Matthey, and Pacific Northwest National Lab and initiated the Sustained Low-Temperature NOx Reduction program at the beginning of 2015. Through this collaboration, we are exploring catalyst formulations and catalyst architectures with enhanced catalytic activity at 150°C; opportunities to approach the desirable ratio of NO and NO2 in the SCR feed gas; options for robust low-temperature reductant delivery; and the requirements for overall system integration. The program is expected to deliver an on-engine demonstration of the technical solution and an assessment of its commercial potential. In the SAE meeting, we will share the initial performance data on engine to

  18. Model Reduction via Reducibility Matrix

    Institute of Scientific and Technical Information of China (English)

    Musa Abdalla; Othman Alsmadi

    2006-01-01

    In this work, a new model reduction technique is introduced. The proposed technique is derived using the matrix reducibility concept. The eigenvalues of the reduced model are preserved; that is, the reduced model eigenvalues are a subset of the full order model eigenvalues. This preservation of the eigenvalues makes the mathematical model closer to the physical model. Finally, the outcomes of this method are fully illustrated using simulations of two numeric examples.

  19. Dimensional Reduction for Conformal Blocks

    CERN Document Server

    Hogervorst, Matthijs

    2016-01-01

    We consider the dimensional reduction of a CFT, breaking multiplets of the d-dimensional conformal group SO(d+1,1) up into multiplets of SO(d,1). This leads to an expansion of d-dimensional conformal blocks in terms of blocks in d-1 dimensions. In particular, we obtain a formula for 3d conformal blocks as an infinite sum over 2F1 hypergeometric functions with closed-form coefficients.

  20. Insular volume reduction in schizophrenia.

    Science.gov (United States)

    Saze, Teruyasu; Hirao, Kazuyuki; Namiki, Chihiro; Fukuyama, Hidenao; Hayashi, Takuji; Murai, Toshiya

    2007-12-01

    Structural and functional abnormalities of the insular cortex have been reported in patients with schizophrenia. Most studies have shown that the insular volumes in schizophrenia patients are smaller than those of healthy people. As the insular cortex is functio-anatomically divided into anterior and posterior subdivisons, recent research is focused on uncovering a specific subdivisional abnormality of the insula in patients with schizophrenia. A recent ROI-based volumetric MRI study demonstrated specific left anterior insular volume reduction in chronic schizophrenia patients (Makris N, Goldstein J, Kennedy D, Hodge S, Caviness V, Faraone S, Tsuang M, Seidman L (2006) Decreased volume of left and total anterior insular lobule in schizophrenia. Schizophr Res 83:155-171). On the other hand, our VBM-based volumetric study revealed a reduction in right posterior insular volume (Yamada M, Hirao K, Namiki C, Hanakawa T, Fukuyama H, Hayashi T, Murai T (2007) Social cognition and frontal lobe pathology in schizophrenia: a voxel-based morphometric study. NeuroImage 35:292-298). In order to address these controversial results, ROI-based subdivisional volumetry was performed using the MRI images from the same population we analyzed in our previous VBM-study. The sample group comprised 20 schizophrenia patients and 20 matched healthy controls. Patients with schizophrenia showed a global reduction in insular gray matter volumes relative to healthy comparison subjects. In a simple comparison of the volumes of each subdivision between the groups, a statistically significant volume reduction in patients with schizophrenia was demonstrated only in the right posterior insula. This study suggests that insular abnormalities in schizophrenia would include anterior as well as posterior parts. Each subdivisional abnormality may impact on different aspects of the pathophysiology and psychopathology of schizophrenia; these relationships should be the focus of future research.

  1. Performance of lazy combinator graph reduction

    NARCIS (Netherlands)

    Hartel, Pieter H.; Hartel, P.H.

    The performance of program-derived combinator graph reduction is known to be superior to that of graph reduction based on a fixed set of standard combinators. The major advantage of program-derived combinator reduction is that it uses less transient store than standard combinator reduction. We show

  2. 20 CFR 226.71 - Initial reduction.

    Science.gov (United States)

    2010-04-01

    ... EMPLOYEE, SPOUSE, AND DIVORCED SPOUSE ANNUITIES Reduction for Workers' Compensation and Disability Benefits... a disability annuity and workers' compensation or a public disability benefit. The reduction ends... the workers compensation or public disability benefit ends. (b) Amount of reduction. The reduction for...

  3. Model Reduction by Manifold Boundaries

    Science.gov (United States)

    Transtrum, Mark K.; Qiu, Peng

    2015-01-01

    Understanding the collective behavior of complex systems from their basic components is a difficult yet fundamental problem in science. Existing model reduction techniques are either applicable under limited circumstances or produce “black boxes” disconnected from the microscopic physics. We propose a new approach by translating the model reduction problem for an arbitrary statistical model into a geometric problem of constructing a low-dimensional, submanifold approximation to a high-dimensional manifold. When models are overly complex, we use the observation that the model manifold is bounded with a hierarchy of widths and propose using the boundaries as submanifold approximations. We refer to this approach as the manifold boundary approximation method. We apply this method to several models, including a sum of exponentials, a dynamical systems model of protein signaling, and a generalized Ising model. By focusing on parameters rather than physical degrees of freedom, the approach unifies many other model reduction techniques, such as singular limits, equilibrium approximations, and the renormalization group, while expanding the domain of tractable models. The method produces a series of approximations that decrease the complexity of the model and reveal how microscopic parameters are systematically “compressed” into a few macroscopic degrees of freedom, effectively building a bridge between the microscopic and the macroscopic descriptions. PMID:25216014

  4. The reduction of packaging waste

    Energy Technology Data Exchange (ETDEWEB)

    Raney, E.A.; Hogan, J.J.; McCollom, M.L.; Meyer, R.J.

    1994-04-01

    Nationwide, packaging waste comprises approximately one-third of the waste disposed in sanitary landfills. the US Department of Energy (DOE) generated close to 90,000 metric tons of sanitary waste. With roughly one-third of that being packaging waste, approximately 30,000 metric tons are generated per year. The purpose of the Reduction of Packaging Waste project was to investigate opportunities to reduce this packaging waste through source reduction and recycling. The project was divided into three areas: procurement, onsite packaging and distribution, and recycling. Waste minimization opportunities were identified and investigated within each area, several of which were chosen for further study and small-scale testing at the Hanford Site. Test results, were compiled into five ``how-to`` recipes for implementation at other sites. The subject of the recipes are as follows: (1) Vendor Participation Program; (2) Reusable Containers System; (3) Shrink-wrap System -- Plastic and Corrugated Cardboard Waste Reduction; (4) Cardboard Recycling ; and (5) Wood Recycling.

  5. Results Evaluation in Reduction Rhinoplasty

    Directory of Open Access Journals (Sweden)

    Arima, Lisandra Megumi

    2011-01-01

    Full Text Available Introduction: Final results evaluation after rhinoplasty is a not a topic widely studied from the patient's viewpoint. Objective:Evaluate the satisfaction of the patients submitted to reduction rhinoplasty, from the questionnaire Rhinoplasty Outcomes Evaluation (ROE. Method: Longitudinal study, retrospective cut type, of the preoperative and postoperative satisfaction. The sample was composed by 28 patients who were submitted to rhinoplasty and answered the ROE questionnaire. Three variables were obtained: satisfaction note that the patient had with his/her image before the surgery; note of satisfaction with the current appearance; the difference of the average satisfaction notes between postoperative and preoperative approaches. Results: The postoperative note was higher than the preoperative in all patients. We noticed a difference between the average of the postoperative and preoperative of 48.3 (p75 considered to be an excellent outcome (67.9%. Conclusions: The ROE questionnaire is a helpful tool to show the satisfaction of the patient submitted to reduction rhinoplasty. About 92% of the patients submitted to reduction rhinoplasty consider the postoperative result to be good or excellent.

  6. From Outermost Reduction Semantics to Abstract Machine

    DEFF Research Database (Denmark)

    Danvy, Olivier; Johannsen, Jacob

    Reduction semantics is a popular format for small-step operational semantics of deterministic programming languages with computational effects. Each reduction semantics gives rise to a reduction-based normalization function where the reduction sequence is enumerated. Refocusing is a practical way...... of the term to enumerate the reduction sequence, in contrast to the reduction-based normalization function. We have discovered that refocusing does not apply as readily for reduction semantics that use an outermost reduction strategy and have overlapping rules where a contractum can be a proper subpart...... of a redex. In this article, we consider such an outermost reduction semantics with backward-overlapping rules, and we investigate how to apply refocusing to still obtain a reduction-free normalization function in the form of an abstract machine....

  7. The anaerobic degradation of organic matter in Danish coastal sediments: iron reduction, manganese reduction, and sulfate reduction

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene; Thamdrup, B; Hansen, Jens Würgler

    1993-01-01

    important than sulfate reduction. Most of the Mn reduction in these sediments may have been coupled to the oxidation of acid volatile sulfides (AVS), rather than to dissimilatory reduction. High rates of metal oxide reduction at all sites were driven by active recycling of both Fe and Mn, encouraged......We used a combination of porewater and solid phase analysis, as well as a series of sediment incubations, to quantify organic carbon oxidation by dissimilatory Fe reduction, Mn reduction, and sulfate reduction, in sediments from the Skagerrak (located off the northeast coast of Jutland, Denmark......). In the deep portion of the basin, surface Mn enrichments reached 3.5 wt%, and Mn reduction was the only important anaerobic carbon oxidation process in the upper 10 cm of the sediment. In the less Mn-rich sediments from intermediate depths in the basin, Fe reduction ranged from somewhat less, to far more...

  8. Regression Testing Cost Reduction Suite

    Directory of Open Access Journals (Sweden)

    Mohamed Alaa El-Din

    2014-08-01

    Full Text Available The estimated cost of software maintenance exceeds 70 percent of total software costs [1], and large portion of this maintenance expenses is devoted to regression testing. Regression testing is an expensive and frequently executed maintenance activity used to revalidate the modified software. Any reduction in the cost of regression testing would help to reduce the software maintenance cost. Test suites once developed are reused and updated frequently as the software evolves. As a result, some test cases in the test suite may become redundant when the software is modified over time since the requirements covered by them are also covered by other test cases. Due to the resource and time constraints for re-executing large test suites, it is important to develop techniques to minimize available test suites by removing redundant test cases. In general, the test suite minimization problem is NP complete. This paper focuses on proposing an effective approach for reducing the cost of regression testing process. The proposed approach is applied on real-time case study. It was found that the reduction in cost of regression testing for each regression testing cycle is ranging highly improved in the case of programs containing high number of selected statements which in turn maximize the benefits of using it in regression testing of complex software systems. The reduction in the regression test suite size will reduce the effort and time required by the testing teams to execute the regression test suite. Since regression testing is done more frequently in software maintenance phase, the overall software maintenance cost can be reduced considerably by applying the proposed approach.

  9. Climate Change and Poverty Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Simon

    2011-08-15

    Climate change will make it increasingly difficult to achieve and sustain development goals. This is largely because climate effects on poverty remain poorly understood, and poverty reduction strategies do not adequately support climate resilience. Ensuring effective development in the face of climate change requires action on six fronts: investing in a stronger climate and poverty evidence base; applying the learning about development effectiveness to how we address adaptation needs; supporting nationally derived, integrated policies and programmes; including the climate-vulnerable poor in developing strategies; and identifying how mitigation strategies can also reduce poverty and enable adaptation.

  10. The CARMA Data Reduction Pipeline

    Science.gov (United States)

    Friedel, D. N.

    2013-10-01

    The Combined Array for Millimeter-wave Astronomy (CARMA) data reduction pipeline (CADRE) has been developed to give investigators a first look at a fully reduced set of their data. It runs automatically on all data produced by the telescope as they arrive in the data archive. CADRE is written in Python and uses Python wrappers for MIRIAD subroutines for direct access to the data. It applies passband, gain and flux calibration to the data sets and produces a set of continuum and spectral line maps in both MIRIAD and FITS format. CADRE has been in production for a year and this poster will discuss the current capabilities and planned improvements.

  11. Memory Reduction via Delayed Simulation

    Directory of Open Access Journals (Sweden)

    Michael Holtmann

    2011-02-01

    Full Text Available We address a central (and classical issue in the theory of infinite games: the reduction of the memory size that is needed to implement winning strategies in regular infinite games (i.e., controllers that ensure correct behavior against actions of the environment, when the specification is a regular omega-language. We propose an approach which attacks this problem before the construction of a strategy, by first reducing the game graph that is obtained from the specification. For the cases of specifications represented by "request-response"-requirements and general "fairness" conditions, we show that an exponential gain in the size of memory is possible.

  12. Geophysics and Seismic Hazard Reduction

    Institute of Scientific and Technical Information of China (English)

    YuGuihua; ZhouYuanze; YuSheng

    2003-01-01

    The earthquake is a natural phenomenon, which often brings serious hazard to the human life and material possession. It is a physical process of releasing interior energy of the earth, which is caused by interior and outer forces in special tectonic environment in the earth, especially within the lithosphere. The earthquake only causes casualty and loss in the place where people inhabit. Seismic hazard reduction is composed of four parts as seismic prediction, hazard prevention and seismic engineering, seismic response and seismic rescuing, and rebuilding.

  13. Noise reduction of spiral ducts.

    Science.gov (United States)

    Lapka, Wojciech; Cempel, Czesław

    2007-01-01

    The paper presents noise reduction (NR) of spiral ducts as a result of computational modeling of acoustic wave propagation. Three-dimensional models were created with the finite element method in COMSOL Multiphysics version 3.3. Nine models of spiral ducts with 1-9 spiral leads were considered. Time-harmonic analysis was used to predict NR, which was shown in spectral and interval frequency bands. Spiral duct performance can be seen as a comparison of NR before and after a change from a circular to a spiral duct.

  14. Model reduction for circuit simulation

    CERN Document Server

    Hinze, Michael; Maten, E Jan W Ter

    2011-01-01

    Simulation based on mathematical models plays a major role in computer aided design of integrated circuits (ICs). Decreasing structure sizes, increasing packing densities and driving frequencies require the use of refined mathematical models, and to take into account secondary, parasitic effects. This leads to very high dimensional problems which nowadays require simulation times too large for the short time-to-market demands in industry. Modern Model Order Reduction (MOR) techniques present a way out of this dilemma in providing surrogate models which keep the main characteristics of the devi

  15. CCD data reductions at ESO

    Science.gov (United States)

    Grosbol, Preben

    The image-processing and data-reduction functions of the IHAP and MIDAS software packages developed at ESO for CCD astronomy are briefly reviewed. IHAP and MIDAS perform the same basic operations on HP 1000 and VAX computers, respectively, and MIDAS is currently being modified to run in the UNIX operating system as well as in VAX VMS. Consideration is given to the special properties of CCD data, the removal of gross errors (due to bad pixels and cosmic-ray events), photometric correction for dark current and sensitivity variations, digital filtering and Fourier transforms, detection and classification algorithms for direct imaging, surface photometry of extended objects, function fitting, and image deconvolution.

  16. XRT -- ROSAT XRT Data Reduction

    Science.gov (United States)

    Davenhall, A. C.; Platon, R. T.

    XRT is a package for reducing data acquired with the ROSAT XRT instruments. The XRT (X-Ray Telescope) was the principal scientific payload of the ROSAT X-ray astronomy satellite. The XRT had two instruments: the PSPC (Position Sensitive Proportional Counter) and the HRI (High Resolution Imager). The XRT package operates on data produced by these instruments and can be used to transform them into calibrated images, spectra, time-series etc. XRT was created by taking the ROSAT XRT-specific functions in the ASTERIX general X-ray astronomy data reduction system and re-packaging them as stand-alone applications.

  17. Cohomological reduction of sigma models

    Energy Technology Data Exchange (ETDEWEB)

    Candu, Constantin; Mitev, Vladimir; Schomerus, Volker [DESY, Hamburg (Germany). Theory Group; Creutzig, Thomas [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy

    2010-01-15

    This article studies some features of quantum field theories with internal supersymmetry, focusing mainly on 2-dimensional non-linear sigma models which take values in a coset superspace. It is discussed how BRST operators from the target space super- symmetry algebra can be used to identify subsectors which are often simpler than the original model and may allow for an explicit computation of correlation functions. After an extensive discussion of the general reduction scheme, we present a number of interesting examples, including symmetric superspaces G/G{sup Z{sub 2}} and coset superspaces of the form G/G{sup Z{sub 4}}. (orig.)

  18. From Outermost Reduction Semantics to Abstract Machine

    DEFF Research Database (Denmark)

    Danvy, Olivier; Johannsen, Jacob

    to transform a reduction-based normalization function into a reduction-free one where the reduction sequence is not enumerated. This reduction-free normalization function takes the form of an abstract machine that navigates from one redex site to the next without systematically detouring via the root...... of a redex. In this article, we consider such an outermost reduction semantics with backward-overlapping rules, and we investigate how to apply refocusing to still obtain a reduction-free normalization function in the form of an abstract machine....

  19. Representative mass reduction in sampling

    DEFF Research Database (Denmark)

    Petersen, Lars; Esbensen, Harry Kim; Dahl, Casper Kierulf

    2004-01-01

    We here present a comprehensive survey of current mass reduction principles and hardware available in the current market. We conduct a rigorous comparison study of the performance of 17 field and/or laboratory instruments or methods which are quantitatively characterized (and ranked) for accuracy...... always be representative in the full Theory of Sampling (TOS) sense. This survey also allows empirical verification of the merits of the famous ??Gy?s formula?? for order-of-magnitude estimation of the Fundamental Sampling Error (FSE).......We here present a comprehensive survey of current mass reduction principles and hardware available in the current market. We conduct a rigorous comparison study of the performance of 17 field and/or laboratory instruments or methods which are quantitatively characterized (and ranked) for accuracy...... dividers, the Boerner Divider, the ??spoon method??, alternate/fractional shoveling and grab sampling. Only devices based on riffle splitting principles (static or rotational) passes the ultimate representativity test (with minor, but significant relative differences). Grab sampling, the overwhelmingly...

  20. Biocatalytic reduction of carboxylic acids.

    Science.gov (United States)

    Napora-Wijata, Kamila; Strohmeier, Gernot A; Winkler, Margit

    2014-06-01

    An increasing demand for non-petroleum-based products is envisaged in the near future. Carboxylic acids such as citric acid, succinic acid, fatty acids, and many others are available in abundance from renewable resources and they could serve as economic precursors for bio-based products such as polymers, aldehyde building blocks, and alcohols. However, we are confronted with the problem that carboxylic acid reduction requires a high level of energy for activation due to the carboxylate's thermodynamic stability. Catalytic processes are scarce and often their chemoselectivity is insufficient. This review points at bio-alternatives: currently known enzyme classes and organisms that catalyze the reduction of carboxylic acids are summarized. Two totally distinct biocatalyst lines have evolved to catalyze the same reaction: aldehyde oxidoreductases from anaerobic bacteria and archea, and carboxylate reductases from aerobic sources such as bacteria, fungi, and plants. The majority of these enzymes remain to be identified and isolated from their natural background in order to evaluate their potential as industrial biocatalysts.

  1. Tri-Sasakian consistent reduction

    CERN Document Server

    Cassani, Davide

    2011-01-01

    We establish a universal consistent Kaluza-Klein truncation of M-theory based on seven-dimensional tri-Sasakian structure. The four-dimensional truncated theory is an N=4 gauged supergravity with three vector multiplets and a non-abelian gauge group, containing the compact factor SO(3). Consistency follows from the fact that our truncation takes exactly the same form as a left-invariant reduction on a specific coset manifold, and we show that the same holds for the various universal consistent truncations recently put forward in the literature. We describe how the global symmetry group SL(2,R) x SO(6,3) is embedded in the symmetry group E7(7) of maximally supersymmetric reductions, and make the connection with the approach of Exceptional Generalized Geometry. Vacuum AdS4 solutions spontaneously break the amount of supersymmetry from N=4 to N=3,1 or 0, and the spectrum contains massive modes. We find a subtruncation to minimal N=3 gauged supergravity as well as an N=1 subtruncation to the SO(3)-invariant secto...

  2. Chemical model reduction under uncertainty

    KAUST Repository

    Malpica Galassi, Riccardo

    2017-03-06

    A general strategy for analysis and reduction of uncertain chemical kinetic models is presented, and its utility is illustrated in the context of ignition of hydrocarbon fuel–air mixtures. The strategy is based on a deterministic analysis and reduction method which employs computational singular perturbation analysis to generate simplified kinetic mechanisms, starting from a detailed reference mechanism. We model uncertain quantities in the reference mechanism, namely the Arrhenius rate parameters, as random variables with prescribed uncertainty factors. We propagate this uncertainty to obtain the probability of inclusion of each reaction in the simplified mechanism. We propose probabilistic error measures to compare predictions from the uncertain reference and simplified models, based on the comparison of the uncertain dynamics of the state variables, where the mixture entropy is chosen as progress variable. We employ the construction for the simplification of an uncertain mechanism in an n-butane–air mixture homogeneous ignition case, where a 176-species, 1111-reactions detailed kinetic model for the oxidation of n-butane is used with uncertainty factors assigned to each Arrhenius rate pre-exponential coefficient. This illustration is employed to highlight the utility of the construction, and the performance of a family of simplified models produced depending on chosen thresholds on importance and marginal probabilities of the reactions.

  3. 40 CFR 721.1375 - Disubstituted nitrobenzene (generic name).

    Science.gov (United States)

    2010-07-01

    ... program and MSDSs do not apply when the written program and MSDS are not required under § 721.72 (a) and... MSDS does not apply when a MSDS in not required under § 721.72(c). (iii) Industrial, commercial, and...

  4. 1,3-Bis(bromomethyl-2-nitrobenzene

    Directory of Open Access Journals (Sweden)

    Muhammad Nadeem Arshad

    2010-04-01

    Full Text Available In the title compound, C8H7Br2NO2, an intermediate for the synthesis of macrocycles, the NO2 group makes a dihedral angle of 65.07 (19° with the arene ring, and the bromomethyl substituents adopt a trans conformation about the ring such that the molecule closely approximates C2 symmetry.

  5. NOX REMOVAL WITH COMBINED SELECTIVE CATALYTIC REDUCTION AND SELECTIVE NONCATALYTIC REDUCTION: PILOT- SCALE TEST RESULTS

    Science.gov (United States)

    Pilot-scale tests were conducted to develop a combined nitrogen oxide (NOx) reduction technology using both selective catalytic reduction (SCR) and selective noncatalytic reduction (SNCR). A commercially available vanadium-and titatnium-based composite honeycomb catalyst and enh...

  6. Carbon Monoxide Silicate Reduction System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Carbon Monoxide Silicate Reduction System (COSRS) is an innovative method that for the first time uses the strong reductant carbon monoxide to both reduce iron...

  7. Reduction mechanism of natural ilmenite with graphite

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-ming; YUAN Zhang-fu; GUO Zhan-cheng; TAN Qiang-qiang; LI Zhao-yi; JIANG Wei-zhong

    2008-01-01

    Reduction of Bama ilmenite concentrate containing 49.78% TiO2 and 27.96% total Fe by graphite was studied using thermogravimetric analysis system under argon gas ambient from 850 to 1 400 ℃. The reduction degree of Bama ilmenite is enhanced with increasing temperature and the molar ratio of carbon to oxygen, and the reaction rate varies with temperature and reduction time simultaneously. The phase transformation, chemical composition, microstructure and morphology of reduced samples were investigated by using X-ray diffractometry, scanning electron microscopy, and energy disperse spectroscopy, respectively. The high content of impurities in Bama ilmenite evidently bates the reduction of ilmenite. Forming the enrichment zone of manganese prevents complete reduction of Fe2+. The reduction products are mostly reduced iron, rutile, reduced rutiles, Ti3O5 and pseudobrookite solid solution. The reduction kinetics was also discussed. The results show that the reduction temperature is a key factor to control reaction rate.

  8. Morphologisation or Reduction by Context?

    DEFF Research Database (Denmark)

    Heegård Petersen, Jan

    2013-01-01

    The article investigates the factors that underlie schwa elision in-te, [d], endings in Standard Copenhagen Danish adjectives and preterite verb forms. The study shows that preterite [d] is much more likely to undergo schwa elision to [d] than adjectival [d]. The data are analysed by use of regre......The article investigates the factors that underlie schwa elision in-te, [d], endings in Standard Copenhagen Danish adjectives and preterite verb forms. The study shows that preterite [d] is much more likely to undergo schwa elision to [d] than adjectival [d]. The data are analysed by use...... that are often mentioned in the literature as causing phonetic reduction. The article discusses whether preterite verb forms can be said to be more grammatical than adjectives, or whether the high frequency schwa elided variant of verbal te is a sign of morphologisation, an allomorph,-t, of the preterite...

  9. PLAINS CO2 REDUCTION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Edward N. Steadman; John A. Harju; Erin M. O' Leary; James A. Sorensen; Daniel J. Daly; Melanie D. Jensen; Thea E. Reikoff

    2004-10-01

    The Plains CO{sub 2} Reduction (PCOR) Partnership continues to make great progress. Task 2 (Technology Deployment) focused on developing information regarding deployment issues to support Task 5 (Modeling and Phase II Action Plans) by providing information to be used to assess CO{sub 2} sequestration opportunities in the PCOR Partnership region. Task 3 (Public Outreach) focused on developing an informational video about CO{sub 2} sequestration. Progress in Task 4 (Sources, Sinks, and Infrastructure) included the continued collection of data regarding CO{sub 2} sources and sinks and data on the performance and costs for CO{sub 2} separation, capture, treatment, and compression for pipeline transportation. Task 5 focused on screening and qualitatively assessing sequestration options. Task 5 activities also continue to be useful in structuring data collection and other activities in Tasks 2, 3, and 5.

  10. The Olympics and harm reduction?

    Directory of Open Access Journals (Sweden)

    Kayser Bengt

    2012-07-01

    Full Text Available Abstract The current anti-doping policy (‘war on doping’ resembles the ‘war on drugs’ in several aspects, including a zero-tolerance approach, ideology encroaching on human rights and public health principles, high cost using public money for repression and control, and attempts to shape internationally harmonized legal frameworks to attain its aim. Furthermore, even if for different reasons, both wars seem not to be able to attain their objectives, and possibly lead to more harm to society than they can prevent. The Olympic buzz is mounting and we can expect multiple headlines in the media on doping and anti-doping stories related to this event. In this article we describe current anti-doping policy, reflect on its multiple unplanned consequences, and end with a discussion, if lessons learned from harm reduction experiences in the illicit drugs field could be applied to anti-doping.

  11. PLAINS CO2 REDUCTION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Edward N. Steadman; John A. Harju; Erin M. O' Leary; James A. Sorensen; Daniel J. Daly; Melanie D. Jensen; Thea E. Reikoff

    2005-01-01

    The Plains CO{sub 2} Reduction (PCOR) Partnership continues to make great progress. Task 2 (Technology Deployment) focused on developing information regarding deployment issues to support Task 5 (Modeling and Phase II Action Plans) by providing information to be used to assess CO{sub 2} sequestration opportunities in the PCOR Partnership region. Task 3 (Public Outreach) focused on developing an informational video about CO{sub 2} sequestration. Progress in Task 4 (Sources, Sinks, and Infrastructure) included the continued collection of data regarding CO{sub 2} sources and sinks and data on the performance and costs for CO{sub 2} separation, capture, treatment, and compression for pipeline transportation. Task 5 focused on screening and qualitatively assessing sequestration options. Task 5 activities also continue to be useful in structuring data collection and other activities in Tasks 2, 3, and 5.

  12. Large Engine Emission Reduction - LEER

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-10-15

    The target of the project LEER is to find the most cost-effective means of today to reduce exhaust gas emissions, particularly NO{sub x} and particulates, of power-plant and ship propulsion diesel engines. The methods are controlling of the combustion and exhaust gas after-treatment. As research methods, theoretical and literature studies as well as engine tests are used. Using the state of the art technology in the whole engine process from combustion control to after treatment is vital for keeping the product competitive in today's engine market. The project consists of two main tasks, Performance and Emission. The Performance task deals with controlling the combustion for optimising the trade-off between fuel consumption and pollutant formation, NO{sub x} in particular. The Emission task concentrates on improving the after treatment technology in particulate reduction, and understanding the particulate formation by gaining information of particulate nature and composition. (orig.)

  13. Wind reduction by aerosol particles

    Science.gov (United States)

    Jacobson, Mark Z.; Kaufman, Yoram J.

    2006-12-01

    Aerosol particles are known to affect radiation, temperatures, stability, clouds, and precipitation, but their effects on spatially-distributed wind speed have not been examined to date. Here, it is found that aerosol particles, directly and through their enhancement of clouds, may reduce near-surface wind speeds below them by up to 8% locally. This reduction may explain a portion of observed ``disappearing winds'' in China, and it decreases the energy available for wind-turbine electricity. In California, slower winds reduce emissions of wind-driven soil dust and sea spray. Slower winds and cooler surface temperatures also reduce moisture advection and evaporation. These factors, along with the second indirect aerosol effect, may reduce California precipitation by 2-5%, contributing to a strain on water supply.

  14. PLAINS CO2 REDUCTION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Edward N. Steadman; John A. Harju; Erin M. O' Leary; James A. Sorensen; Daniel J. Daly; Melanie D. Jensen; Thea E. Reikoff

    2005-01-01

    The Plains CO{sub 2} Reduction (PCOR) Partnership continues to make great progress. Task 2 (Technology Deployment) focused on developing information regarding deployment issues to support Task 5 (Modeling and Phase II Action Plans) by providing information to be used to assess CO{sub 2} sequestration opportunities in the PCOR Partnership region. Task 3 (Public Outreach) focused on developing an informational video about CO{sub 2} sequestration. Progress in Task 4 (Sources, Sinks, and Infrastructure) included the continued collection of data regarding CO{sub 2} sources and sinks and data on the performance and costs for CO{sub 2} separation, capture, treatment, and compression for pipeline transportation. Task 5 focused on screening and qualitatively assessing sequestration options. Task 5 activities also continue to be useful in structuring data collection and other activities in Tasks 2, 3, and 5.

  15. Drag Reduction of Bacterial Cellulose Suspensions

    Directory of Open Access Journals (Sweden)

    Satoshi Ogata

    2011-01-01

    Full Text Available Drag reduction due to bacterial cellulose suspensions with small environmental loading was investigated. Experiments were carried out by measuring the pressure drop in pipe flow. It was found that bacterial cellulose suspensions give rise to drag reduction in the turbulent flow range. We observed a maximum drag reduction ratio of 11% and found that it increased with the concentration of the bacterial cellulose suspension. However, the drag reduction effect decreased in the presence of mechanical shear.

  16. Reductions for Entrepreneurs in Health Insurance Contributions

    Directory of Open Access Journals (Sweden)

    Paweł Lenio

    2014-09-01

    Full Text Available This paper describes the reductions for entrepreneurs in health insurance contributions. Only entrepreneurs from specific social groups can take advantage of said reductions. They apply only to people retired, on pensions or handicapped. The reductions are also dependent on the potential recipient's income and revenue of the company. Handicapped entrepreneurs can benefit from some additional privileges as well. Author analyzes the legal regulations behind these reductions and exposes their shortcomings which cause the benefits to be rarely used.

  17. Reductions for Entrepreneurs in Health Insurance Contributions

    OpenAIRE

    Paweł Lenio

    2014-01-01

    This paper describes the reductions for entrepreneurs in health insurance contributions. Only entrepreneurs from specific social groups can take advantage of said reductions. They apply only to people retired, on pensions or handicapped. The reductions are also dependent on the potential recipient's income and revenue of the company. Handicapped entrepreneurs can benefit from some additional privileges as well. Author analyzes the legal regulations behind these reductions and exposes their sh...

  18. Sulphate reduction experiment: SURE-1

    Energy Technology Data Exchange (ETDEWEB)

    Pedersen, K.; Arlinger, J.; Bengtsson, A.; Edlund, J.; Eriksson, L.; Hallbeck, L.; Johansson, J.; Paeaejaervi, A.; Rabe, L. [Microbial Analytics Sweden AB, Moelnlycke (Sweden)

    2013-11-15

    It was previously concluded that opposing gradients of sulphate and methane, observations of 16S rDNA sequences displaying great similarity to those of anaerobic methane-oxidizing Archaea, and a peak in sulphide concentration in groundwater from a depth of 250-350 m in Olkiluoto, Finland, indicated proper conditions for methane oxidation with sulphate. In the present research (SURE-1), pressure-resistant, gas-tight circulating systems were constructed to enable the investigation of attached and unattached anaerobic microbial populations from a depth of 327 m in Olkiluoto under in situ pressure (2.4 MPa), diversity, dissolved gas, and hydrochemical conditions of groundwater station ONKPVA6. Three parallel flow cell cabinets were configured to allow observation of the influence on microbial metabolic activity of 11 mM methane, 11 mM methane plus 10 mM H{sub 2}, or 2.1 mM O{sub 2} plus 7.9 mM N{sub 2} (i.e., air). The concentrations of these gases and of organic acids and carbon, sulphur chemistry, pH and E{sub h}, ATP, numbers of cultivable microorganisms, and total numbers of cells and bacteriophages were subsequently recorded under batch conditions for 105 d. The system containing H{sub 2} and methane displayed microbial reduction of 0.7 mM sulphate to sulphide, while the system containing only methane produced 0.2 mM reduced sulphate. The system containing added air became inhibited and displayed no signs of microbial activity. Added H{sub 2} and methane induced increasing numbers of lysogenic bacteriophages per cell. It appears possible that a microbial anaerobic methane-oxidizing process coupled to acetate formation and sulphate reduction may be ongoing in aquifers at a depth of 250-350 m in Olkiluoto, but clear evidence of such an AOM process was not obtained. (orig.)

  19. Geometric Reductivity--A Quotient Space Approach

    CERN Document Server

    Sastry, Pramathanath

    2010-01-01

    We give another proof that a reductive algebraic group is geometrically reductive. We show that a quotient of the semi-stable locus (by a linear action of a reductive algebraic group on a projective scheme) exists, and from this Haboush's Theorem (Mumford's Conjecture) follows.

  20. The Wisdom of Class-Size Reduction

    Science.gov (United States)

    Graue, Elizabeth; Hatch, Kelly; Rao, Kalpana; Oen, Denise

    2007-01-01

    In this study, the authors explore the implementation of a statewide class-size reduction program in nine high-poverty schools. Through qualitative methods, they examined how schools used class-size reduction to change staffing patterns and instructional programs. Requiring changes in space allocation, class-size reduction was accomplished through…

  1. Generalized Time-Limited Balanced Reduction Method

    DEFF Research Database (Denmark)

    Shaker, Hamid Reza; Shaker, Fatemeh

    2013-01-01

    In this paper, a new method for model reduction of bilinear systems is presented. The proposed technique is from the family of gramian-based model reduction methods. The method uses time-interval generalized gramians in the reduction procedure rather than the ordinary generalized gramians...

  2. Generalized Time-Limited Balanced Reduction Method

    DEFF Research Database (Denmark)

    Shaker, Hamid Reza; Shaker, Fatemeh

    2013-01-01

    In this paper, a new method for model reduction of bilinear systems is presented. The proposed technique is from the family of gramian-based model reduction methods. The method uses time-interval generalized gramians in the reduction procedure rather than the ordinary generalized gramians and in ...

  3. Identifying the Rhetoric of Uncertainty Reduction.

    Science.gov (United States)

    Williams, David E.

    Offering a rhetorical perspective of uncertainty reduction, this paper (1) discusses uncertainty reduction theory and dramatism; (2) identifies rhetorical strategies inherent in C. W. Berger and R. J. Calabrese's theory; (3) extends predicted outcome value to influenced outcome value; and (4) argues that the goal of uncertainty reduction and…

  4. Ultrasound-Assisted Distal Radius Fracture Reduction

    Science.gov (United States)

    Socransky, Steve; Skinner, Andrew; Bromley, Mark; Smith, Andrew; Anawati, Alexandre; Middaugh, Jeff; Ross, Peter

    2016-01-01

    Introduction Closed reduction of distal radius fractures (CRDRF) is a commonly performed emergency department (ED) procedure. The use of point-of-care ultrasound (PoCUS) to diagnose fractures and guide reduction has previously been described. The primary objective of this study was to determine if the addition of PoCUS to CRDRF changed the perception of successful initial reduction. This was measured by the rate of further reduction attempts based on PoCUS following the initial clinical determination of achievement of best possible reduction. Methods  We performed a multicenter prospective cohort study, using a convenience sample of adult ED patients presenting with a distal radius fracture to five Canadian EDs. All study physicians underwent standardized PoCUS training for fractures. Standard clinically-guided best possible fracture reduction was initially performed. PoCUS was then used to assess the reduction adequacy. Repeat reduction was performed if deemed indicated. A post-reduction radiograph was then performed. Clinician impression of reduction adequacy was scored on a 5 point Likert scale following the initial clinically-guided reduction and following each PoCUS scan and the post-reduction radiograph. Results  There were 131 patients with 132 distal radius fractures. Twelve cases were excluded prior to analysis. There was no significant difference in the assessment of the initial reduction status by PoCUS as compared to the clinical exam (mean score: 3.8 vs. 3.9; p = 0.370; OR 0.89; 95% CI 0.46 to 1.72; p = 0.87). Significantly fewer cases fell into the uncertain category with PoCUS than with clinical assessment (2 vs 12; p = 0.008). Repeat reduction was performed in 49 patients (41.2%). Repeat reduction led to a significant improvement (p < 0.001) in the PoCUS determined adequacy of reduction (mean score: 4.3 vs 3.1; p < 0.001). In this group, the odds ratio for adequate vs. uncertain or inadequate reduction assessment using PoCUS was 12.5 (95% CI 3

  5. PLAINS CO2 REDUCTION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Edward N. Steadman; John A. Harju; Erin M. O' Leary; James A. Sorensen; Daniel J. Daly; Melanie D. Jensen; Lisa S. Botnen

    2005-07-01

    The Plains CO{sub 2} Reduction (PCOR) Partnership characterization work is nearing completion, and most remaining efforts are related to finalizing work products. Task 2 (Technology Deployment) has developed a Topical Report entitled ''Deployment Issues Related to Geologic CO{sub 2} Sequestration in the PCOR Partnership Region''. Task 3 (Public Outreach) has developed an informational Public Television program entitled ''Nature in the Balance'', about CO{sub 2} sequestration. The program was completed and aired on Prairie Public Television in this quarter. Task 4 (Sources, Sinks, and Infrastructure) efforts are nearing completion, and data regarding CO{sub 2} sources and sinks and data on the performance and costs for CO{sub 2} separation, capture, treatment, and compression for pipeline transportation are being incorporated into a series of topical reports. The expansion of the Decision Support System Geographic Information System database has continued with the development of a ''save bookmark'' feature that allows users to save a map from the system easily. A feature that allows users to develop a report that summarizes CO{sub 2} sequestration parameters was also developed. Task 5 (Modeling and Phase II Action Plans) focused on screening and qualitatively assessing sequestration options and developing economic estimates for important regional CO{sub 2} sequestration strategies.

  6. PLAINS CO2 REDUCTION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Edward N. Steadman; John A. Harju; Erin M. O' Leary; James A. Sorensen; Daniel J. Daly; Melanie D. Jensen; Thea E. Reikoff

    2005-04-01

    The Plains CO{sub 2} Reduction (PCOR) Partnership continues to make great progress. Task 2 (Technology Deployment) focused on developing information regarding deployment issues to support Task 5 (Modeling and Phase II Action Plans) and provided information to be used to assess CO{sub 2} sequestration opportunities in the PCOR Partnership region. Task 2 efforts also included preparation of a draft topical report entitled ''Deployment Issues Related to Geologic CO{sub 2} Sequestration in the PCOR Partnership Region'', which is nearing completion. Task 3 (Public Outreach) focused on developing an informational video about CO{sub 2} sequestration. The video will be completed and aired on Prairie Public Television in the next quarter. Progress in Task 4 (Sources, Sinks, and Infrastructure) included the continued collection of data regarding CO{sub 2} sources and sinks and data on the performance and costs for CO{sub 2} separation, capture, treatment, and compression for pipeline transportation. The addition of the Canadian province of Alberta to the PCOR Partnership region expanded the decision support system (DSS) geographic information system database. Task 5 screened and qualitatively assessed sequestration options. Task 5 activities also continue to be useful in structuring data collection and other activities in Tasks 2, 3, and 5.

  7. 20 CFR 410.540 - Reductions; more than one reduction event.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Reductions; more than one reduction event. 410.540 Section 410.540 Employees' Benefits SOCIAL SECURITY ADMINISTRATION FEDERAL COAL MINE HEALTH...; more than one reduction event. If a reduction for receipt of State benefits (see § 410.520) and a...

  8. Low-valent titanium induced reductive cyclization of nitro com pounds and aliphatic ketones: facile synthesis of 3, 4-dihydro ( 2 H ) - 1,2,4- benzothiadiazine- 1,1-dioxides

    Institute of Scientific and Technical Information of China (English)

    ZHONG, Wei-Hui; CHEN, Xiao-Yuan; ZHANG, Yong-Min

    2000-01-01

    The intermolecular reductivc cyclization of o-nitrobenzene sulfonamides with aliphafic ketones induced by TiCl4/Sm sys tem was studied and a series of 3,3-disubstituted-3,4-dihydro (2H)-1, 2, 4-benzothiadiazine-1, 1-dioxides were synthesized in moderate to high yields under mild and neutral conditions.

  9. Monoclonal antibody disulfide reduction during manufacturing

    Science.gov (United States)

    Hutterer, Katariina M.; Hong, Robert W.; Lull, Jonathon; Zhao, Xiaoyang; Wang, Tian; Pei, Rex; Le, M. Eleanor; Borisov, Oleg; Piper, Rob; Liu, Yaoqing Diana; Petty, Krista; Apostol, Izydor; Flynn, Gregory C.

    2013-01-01

    Manufacturing-induced disulfide reduction has recently been reported for monoclonal human immunoglobulin gamma (IgG) antibodies, a widely used modality in the biopharmaceutical industry. This effect has been tied to components of the intracellular thioredoxin reduction system that are released upon cell breakage. Here, we describe the effect of process parameters and intrinsic molecule properties on the extent of reduction. Material taken from cell cultures at the end of production displayed large variations in the extent of antibody reduction between different products, including no reduction, when subjected to the same reduction-promoting harvest conditions. Additionally, in a reconstituted model in which process variables could be isolated from product properties, we found that antibody reduction was dependent on the cell line (clone) and cell culture process. A bench-scale model using a thioredoxin/thioredoxin reductase regeneration system revealed that reduction susceptibility depended on not only antibody class but also light chain type; the model further demonstrates that the trend in reducibility was identical to DTT reduction sensitivity following the order IgG1λ > IgG1κ > IgG2λ > IgG2κ. Thus, both product attributes and process parameters contribute to the extent of antibody reduction during production. PMID:23751615

  10. Lake Nasser evaporation reduction study

    Directory of Open Access Journals (Sweden)

    Hala M.I. Ebaid

    2010-10-01

    Full Text Available This study aims to evaluate the reduction of evaporation of Lake Nasser’s water caused by disconnecting (fully or partially some of its secondary channels (khors. This evaluation integrates remote sensing, Geographic Information System (GIS techniques, aerodynamic principles, and Landsat7 ETM+ images. Three main procedures were carried out in this study; the first derived the surface temperature from Landsat thermal band; the second derived evaporation depth and approximate evaporation volume for the entire lake, and quantified evaporation loss to the secondary channels’ level over one month (March by applied aerodynamic principles on surface temperature of the raster data; the third procedure applied GIS suitability analysis to determine which of these secondary channels (khors should be disconnected. The results showed evaporation depth ranging from 2.73 mm/day at the middle of the lake to 9.58 mm/day at the edge. The evaporated water-loss value throughout the entire lake was about 0.86 billion m3/month (March. The analysis suggests that it is possible to save an approximate total evaporation volume loss of 19.7 million m3/month (March, and thus 2.4 billion m3/year, by disconnecting two khors with approximate construction heights of 8 m and 15 m. In conclusion, remote sensing and GIS are useful for applications in remote locations where field-based information is not readily available and thus recommended for decision makers remotely planning in water conservation and management.

  11. Development of an expert data reduction assistant

    Science.gov (United States)

    Miller, Glenn E.; Johnston, Mark D.; Hanisch, Robert J.

    1993-01-01

    We propose the development of an expert system tool for the management and reduction of complex datasets. the proposed work is an extension of a successful prototype system for the calibration of CCD (charge coupled device) images developed by Dr. Johnston in 1987. (ref.: Proceedings of the Goddard Conference on Space Applications of Artificial Intelligence). The reduction of complex multi-parameter data sets presents severe challenges to a scientist. Not only must a particular data analysis system be mastered, (e.g. IRAF/SDAS/MIDAS), large amounts of data can require many days of tedious work and supervision by the scientist for even the most straightforward reductions. The proposed Expert Data Reduction Assistant will help the scientist overcome these obstacles by developing a reduction plan based on the data at hand and producing a script for the reduction of the data in a target common language.

  12. Emergence, Reduction and Supervenience: a Varied Landscape

    CERN Document Server

    Butterfield, Jeremy

    2011-01-01

    This is one of two papers about emergence, reduction and supervenience. It expounds these notions and analyses the general relations between them. The companion paper analyses the situation in physics, especially limiting relations between physical theories. I shall take emergence as behaviour that is novel and robust relative to some comparison class. I shall take reduction as deduction using appropriate auxiliary definitions. And I shall take supervenience as a weakening of reduction, viz. to allow infinitely long definitions. The overall claim of this paper will be that emergence is logically independent both of reduction and of supervenience. In particular, one can have emergence with reduction, as well as without it; and emergence without supervenience, as well as with it. Of the subsidiary claims, the four main ones (each shared with some other authors) are: (i): I defend the traditional Nagelian conception of reduction (Section 3); (ii): I deny that the multiple realizability argument causes trouble fo...

  13. Nox reduction in the sintering process

    Institute of Scientific and Technical Information of China (English)

    Yan-guang Chen; Zhan-cheng Guo; Zhi Wang; Gen-sheng Feng

    2009-01-01

    A new process, NOx reduction with recycling flue gas and modifying coke breeze, was proposed. The effects of modified coke breeze and recycled flue gas on NOx reduction were investigated by sinter pot tests. The results show that the NOx reduction rate is over 10wt% in the sintering of modified coke breeze, the effects of the additives on NOx reduction are: CeO2CaOK2CO3.The NOx reduction rate increases with the amount of recycled flue gas, and is 22.35wt% in the sintering with recycling 30vo1% of the flue gas. When 30vo1% of the flue gas is recycled into the sintering of CeO2, CaO, and K2CO3 modified coke breeze, the NOx reduc-tion rates are 36.10wt%, 32.56wt%, and 32.17wt%, respectively.

  14. 50 CFR 600.1011 - Reduction methods and other conditions.

    Science.gov (United States)

    2010-10-01

    ... reduction loan balance that results from all reduction payments that NMFS actually makes and does not...' tender of the reduction payment for the reduction permit, forever revoked. Each reduction permit holder shall, upon NMFS' tender of the reduction payment, surrender the original reduction permit to NMFS....

  15. Model Reduction for Complex Hyperbolic Networks

    OpenAIRE

    Himpe, Christian; Ohlberger, Mario

    2013-01-01

    We recently introduced the joint gramian for combined state and parameter reduction [C. Himpe and M. Ohlberger. Cross-Gramian Based Combined State and Parameter Reduction for Large-Scale Control Systems. arXiv:1302.0634, 2013], which is applied in this work to reduce a parametrized linear time-varying control system modeling a hyperbolic network. The reduction encompasses the dimension of nodes and parameters of the underlying control system. Networks with a hyperbolic structure have many app...

  16. REDUCTIONS WITHOUT REGRET: HISTORICAL PERSPECTIVES

    Energy Technology Data Exchange (ETDEWEB)

    Swegle, J.; Tincher, D.

    2013-09-09

    This is the first of three papers (in addition to an introductory summary) aimed at providing a framework for evaluating future reductions or modifications of the U.S. nuclear force, first by considering previous instances in which nuclear-force capabilities were eliminated; second by looking forward into at least the foreseeable future at the features of global and regional deterrence (recognizing that new weapon systems currently projected will have expected lifetimes stretching beyond our ability to predict the future); and third by providing examples of past or possible undesirable outcomes in the shaping of the future nuclear force, as well as some closing thoughts for the future. This paper examines the circumstances and consequences of the elimination of The INF-range Pershing II ballistic missile and Gryphon Ground-Launched Cruise Missile (GLCM), deployed by NATO under a dual-track strategy to counter Soviet intermediate-range missiles while pursuing negotiations to limit or eliminate all of these missiles. The Short-Range Attack Missile (SRAM), which was actually a family of missiles including SRAM A, SRAM B (never deployed), and SRAM II and SRAM T, these last two cancelled during an over-budget/behind-schedule development phase as part of the Presidential Nuclear Initiatives of 1991 and 1992. The nuclear-armed version of the Tomahawk Land-Attack Cruise Missile (TLAM/N), first limited to shore-based storage by the PNIs, and finally eliminated in deliberations surrounding the 2010 Nuclear Posture Review Report. The Missile-X (MX), or Peacekeeper, a heavy MIRVed ICBM, deployed in fixed silos, rather than in an originally proposed mobile mode. Peacekeeper was likely intended as a bargaining chip to facilitate elimination of Russian heavy missiles. The plan failed when START II did not enter into force, and the missiles were eliminated at the end of their intended service life. The Small ICBM (SICBM), or Midgetman, a road-mobile, single-warhead missile for

  17. Reductive photocatalysis and smart inks.

    Science.gov (United States)

    Mills, Andrew; Wells, Nathan

    2015-05-21

    Semiconductor-sensitised photocatalysis is a well-established and growing area of research, innovation and commercialisation; the latter being mostly limited to the use of TiO2 as the semiconductor. Most of the work on semiconductor photocatalytic systems uses oxygen as the electron acceptor and explores a wide range of electron donors; such systems can be considered to be examples of oxidative photocatalysis, OP. OP underpins most current examples of commercial self-cleaning materials, such as: glass, tiles, concrete, paint and fabrics. OP, and its myriad of applications, have been reviewed extensively over the years both in this journal and elsewhere. However, the ability of TiO2, and other semiconductor sensitisers, to promote reductive photocatalysis, RP, especially of dyes, is significant and, although less well-known, is of growing importance. In such systems, the source of the electrons is some easily oxidised species, such as glycerol. One recent, significant example of a RP process is with respect to photocatalyst activity indicator inks. paiis, which provide a measure of the activity of a photocatalytic film under test via the rate of change of colour of the dye in the ink coating due to irreversible RP. In contrast, by incorporating the semiconductor sensitiser in the ink, rather than outside it, it is possible to create an effective UV dosimeter, based on RP, which can be used as a sun-burn warning indicator. In the above examples the dye is reduced irreversibly, but when the photocatalyst in an ink is used to reversibly photoreduce a dye, a novel, colourimetric oxygen-sensitive indicator ink can be created, which has commercial potential in the food packaging industry. Finally, if no dye is present in the ink, and the semiconductor photocatalyst-loaded ink film coats an easily reduced substrate, such as a metal oxide film, then it can be used to reduce the latter and so, for example, clean up tarnished steel. The above are examples of smart inks, i

  18. First Class Call Stacks: Exploring Head Reduction

    Directory of Open Access Journals (Sweden)

    Philip Johnson-Freyd

    2016-06-01

    Full Text Available Weak-head normalization is inconsistent with functional extensionality in the call-by-name λ-calculus. We explore this problem from a new angle via the conflict between extensionality and effects. Leveraging ideas from work on the λ-calculus with control, we derive and justify alternative operational semantics and a sequence of abstract machines for performing head reduction. Head reduction avoids the problems with weak-head reduction and extensionality, while our operational semantics and associated abstract machines show us how to retain weak-head reduction's ease of implementation.

  19. What is dimensional reduction really telling us?

    CERN Document Server

    Coumbe, Daniel

    2015-01-01

    Numerous approaches to quantum gravity report a reduction in the number of spacetime dimensions at the Planck scale. However, accepting the reality of dimensional reduction also means accepting its consequences, including a variable speed of light. We provide numerical evidence for a variable speed of light in the causal dynamical triangulation (CDT) approach to quantum gravity, showing that it closely matches the superluminality implied by dimensional reduction. We argue that reconciling the appearance of dimensional reduction with a constant speed of light may require modifying our understanding of time, an idea originally proposed in Ref. 1.

  20. Solvothermal reduction of graphene oxide in dimethylformamide

    Science.gov (United States)

    Kim, Sujin; Choi, Kwangrok; Park, Sungjin

    2016-11-01

    The reduction of graphene oxide (G-O) is one of the most promising methods for the large scale production of graphene-based materials. In this paper, we report a simple and non-toxic method to produce reduced graphene oxide (rG-O) by refluxing G-O in N, N-dimethylformamide without the aid of a reducing agent. The rG-O materials with high degrees of reduction are prepared and the levels of reduction are controlled using reflux time. Successful reduction is confirmed by combustion-based elemental analysis and X-ray photoelectron and Fourier transform infrared spectroscopy.

  1. Chromate reduction by rabbit liver aldehyde oxidase

    Energy Technology Data Exchange (ETDEWEB)

    Banks, R.B.; Cooke, R.T. Jr.

    1986-05-29

    Chromate was reduced during the oxidation of 1-methylnicotinamide chlorine by partially purified rabbit liver aldehyde oxidase. In addition to l-methylnicotinamide, several other electron donor substrates for aldehyde oxidase were able to support the enzymatic chromate reduction. The reduction required the presence of both enzyme and the electron donor substrate. The rate of the chromate reduction was retarded by inhibitors or aldehyde oxidase but was not affected by substrates or inhibitors of xanthine oxidase. These results are consistent with the involvement of aldehyde oxidase in the reduction of chromate by rabbit liver cytosolic enzyme preparations.

  2. Dissolution and reduction of magnetite by bacteria

    Science.gov (United States)

    Kostka, J. E.; Nealson, K. H.

    1995-01-01

    Magnetite (Fe3O4) is an iron oxide of mixed oxidation state [Fe(II), Fe(III)] that contributes largely to geomagnetism and plays a significant role in diagenesis in marine and freshwater sediments. Magnetic data are the primary evidence for ocean floor spreading and accurate interpretation of the sedimentary magnetic record depends on an understanding of the conditions under which magnetite is stable. Though chemical reduction of magnetite by dissolved sulfide is well known, biological reduction has not been considered likely based upon thermodynamic considerations. This study shows that marine and freshwater strains of the bacterium Shewanella putrefaciens are capable of the rapid dissolution and reduction of magnetite, converting millimolar amounts to soluble Fe(II)in a few days at room temperature. Conditions under which magnetite reduction is optimal (pH 5-6, 22-37 degrees C) are consistent with an enzymatic process and not with simple chemical reduction. Magnetite reduction requires viable cells and cell contact, and it appears to be coupled to electron transport and growth. In a minimal medium with formate or lactate as the electron donor, more than 10 times the amount of magnetite was reduced over no carbon controls. These data suggest that magnetite reduction is coupled to carbon metabolism in S. putrefaciens. Bacterial reduction rates of magnetite are of the same order of magnitude as those estimated for reduction by sulfide. If such remobilization of magnetite occurs in nature, it could have a major impact on sediment magnetism and diagenesis.

  3. Reduction of Nitro Aromatic Compounds in Fe(0) -CO2-H2O Systems: Implications for Groundwater Remediation with Iron Metal

    Science.gov (United States)

    1995-07-01

    second only to organochlorine functional groups. NACs are common environmental contaminants because of their use as munitions, insecticides, herbicides ...contaminants, as is the case with the nitro-PAHs and nitrophenols found in atmospheric waters. 11.12 Among the processes contributing to the environmental fate...substituted nitrobenzenes and nitrophenols to mineral surfaces. Environ. Sei. Technol. 1993, 27, 316-326. (57) Palmer, C. D.; Cherry, J. A

  4. Isothermal reduction of titanomagnetite concentrates containing coal

    Institute of Scientific and Technical Information of China (English)

    Tu Hu; Xue-wei Lü; Chen-guang Bai; Gui-bao Qiu

    2014-01-01

    The isothermal reduction of the Panzhihua titanomagnetite concentrates (PTC) briquette containing coal under argon atmosphere was investigated by thermogravimetry in an electric resistance furnace within the temperature range of 1250-1350°C. The samples reduced in argon at 1350°C for different time were examined by X-ray diffraction (XRD) analysis. Model-fitting and model-free methods were used to evaluate the apparent activation energy of the reduction reaction. It is found that the reduction rate is very fast at the early stage, and then, at a later stage, the reduction rate becomes slow and decreases gradually to the end of the reduction. It is also observed that the reduction of PTC by coal depends greatly on the temperature. At high temperatures, the reduction degree reaches high values faster and the final value achieved is higher than at low temperatures. The final phase composition of the reduced PTC-coal briquette consists in iron and fer-rous-pseudobrookite (FeTi2O5), while Fe2.75Ti0.25O4, Fe2.5Ti0.5O4, Fe2.25Ti0.75O4, ilmenite (FeTiO3) and wustite (FeO) are intermediate products. The reaction rate is controlled by the phase boundary reaction for reduction degree less than 0.2 with an apparent activation energy of about 68 kJ·mol-1 and by three-dimensional diffusion for reduction degree greater than 0.75 with an apparent activation energy of about 134 kJ·mol-1. For the reduction degree in the range of 0.2-0.75, the reaction rate is under mixed control, and the activation energy increases with the increase of the reduction degree.

  5. Achieve inventory reduction and improve customer service?

    Science.gov (United States)

    Moody, M C

    2000-05-01

    Is it really possible to achieve significant reductions in your manufacturing inventories while improving customer service? If you really want to achieve significant inventory reductions, focus on the root causes, and develop countermeasures and a work plan, to execute your countermeasures. Include measurements for recording your progress, and deploy your countermeasures until they are no longer required, or until new ones are needed.

  6. Transfinite reductions in orthogonal term rewriting systems

    NARCIS (Netherlands)

    J.R. Kennaway (Richard); J.W. Klop (Jan Willem); M.R. Sleep (Ronan); F.-J. de Vries (Fer-Jan)

    1991-01-01

    textabstractStrongly convergent reduction is the fundamental notion of reduction in infinitary orthogonal term rewriting systems (OTRSs). For these we prove the Transfinite Parallel Moves Lemma and the Compressing Lemma. Strongness is necessary as shown by counterexamples. Normal forms, which we

  7. Time-Weighted Balanced Stochastic Model Reduction

    DEFF Research Database (Denmark)

    Tahavori, Maryamsadat; Shaker, Hamid Reza

    2011-01-01

    A new relative error model reduction technique for linear time invariant (LTI) systems is proposed in this paper. Both continuous and discrete time systems can be reduced within this framework. The proposed model reduction method is mainly based upon time-weighted balanced truncation and a recent...

  8. Growth and poverty reduction in Tanzania

    DEFF Research Database (Denmark)

    Arndt, Channing; Demery, Lionel; McKay, Andy

    . The household survey data documents a limited reduction in consumption poverty over the period, and what poverty reduction there has been has mostly occurred in Dar es Salaam. Indicators of non-monetary poverty have gradually improved over the past 20 years but significant differences across the country remain....

  9. Growth and poverty reduction in Tanzania

    DEFF Research Database (Denmark)

    Arndt, Channing; Demery, Lionel; McKay, Andy

    . The household survey data documents a limited reduction in consumption poverty over the period, and what poverty reduction there has been has mostly occurred in Dar es Salaam. Indicators of non-monetary poverty have gradually improved over the past 20 years but significant differences across the country remain....

  10. An algorithm for reduct cardinality minimization

    KAUST Repository

    AbouEisha, Hassan M.

    2013-12-01

    This is devoted to the consideration of a new algorithm for reduct cardinality minimization. This algorithm transforms the initial table to a decision table of a special kind, simplify this table, and use a dynamic programming algorithm to finish the construction of an optimal reduct. Results of computer experiments with decision tables from UCI ML Repository are discussed. © 2013 IEEE.

  11. Handling Biological Complexity Using Kron Reduction

    NARCIS (Netherlands)

    Jayawardhana, Bayu; Rao, Shodhan; Sikkema, Ward; Bakker, Barbara; Camlibel, Kanat; Julius, Agung; Pasumarthy, Ramkrishna; Scherpen, Jacquelien

    2015-01-01

    We revisit a model reduction method for detailed-balanced chemical reaction networks based on Kron reduction on the graph of complexes. The resulting reduced model preserves a number of important properties of the original model, such as, the kinetics law and identity of the chemical species. For de

  12. Biological sulphate reduction with synthesis gas.

    NARCIS (Netherlands)

    Houten, van R.T.

    1996-01-01

    The objectives of this thesis are (1) to study the feasibility of using synthesis gas as electron donor and carbon source for biological sulphate reduction and (2) to develop criteria for design and operation of gas- lift bioreactors for sulphate reduction using immobilized biomass.At appeared that

  13. Representations of reductive normal algebraic monoids

    OpenAIRE

    Doty, Stephen

    2014-01-01

    The rational representation theory of a reductive normal algebraic monoid (with one-dimensional center) forms a highest weight category, in the sense of Cline, Parshall, and Scott. This is a fundamental fact about the representation theory of reductive normal algebraic monoids. We survey how this result was obtained, and treat some natural examples coming from classical groups.

  14. Harm Reduction in MSW Substance Abuse Courses

    Science.gov (United States)

    Eversman, Michael H.

    2012-01-01

    Professional social work largely has endorsed the empirically supported paradigm of harm reduction in relation to substance abuse issues. Despite literature detailing similarities between social work and harm reduction, little is known about its presence in MSW substance abuse coursework. A purposive sample of 133 social work faculty from…

  15. Handling Biological Complexity Using Kron Reduction

    NARCIS (Netherlands)

    Jayawardhana, Bayu; Rao, Shodhan; Sikkema, Ward; Bakker, Barbara; Camlibel, Kanat; Julius, Agung; Pasumarthy, Ramkrishna; Scherpen, Jacquelien

    2015-01-01

    We revisit a model reduction method for detailed-balanced chemical reaction networks based on Kron reduction on the graph of complexes. The resulting reduced model preserves a number of important properties of the original model, such as, the kinetics law and identity of the chemical species. For

  16. Reduction of soil erosion on forest roads

    Science.gov (United States)

    Edward R. Burroughs; John G. King

    1989-01-01

    Presents the expected reduction in surface erosion from selected treatments applied to forest road traveledways, cutslopes, fillslopes, and ditches. Estimated erosion reduction is expressed as functions of ground cover, slope gradient, and soil properties whenever possible. A procedure is provided to select rock riprap size for protection of the road ditch.

  17. National Satellite Disaster Reduction Application Service

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The groundbreaking ceremony for National Satellite Disaster Reduction Application Service was held on January 22,2008 in Beijing.The establishment of the center will further improve the disaster monitoring system using remote sensing technology and provides a platform for the application of remote sensing technology and satellite constellation in China's disaster reduction and relief services.

  18. SELECTIVE CATALYTIC REDUCTION MERCURY FIELD SAMPLING PROJECT

    Science.gov (United States)

    A lack of data still exists as to the effect of selective catalytic reduction (SCR), selective noncatalytic reduction (SNCR), and flue gas conditioning on the speciation and removal of mercury (Hg) at power plants. This project investigates the impact that SCR, SNCR, and flue gas...

  19. Integrated Countermeasures for Urban Industrial Disaster Reduction

    Institute of Scientific and Technical Information of China (English)

    JIN Lei

    2001-01-01

    The 2nd UN World Conference on Disaster Reduction convened in July 1999 proposed the "Geneva Strategy" which highlighted the need that disaster reduction should be focused on cities and communities in the 21st Cent try. Having long been engaged in research on urban disaster reduction, the author noticed that although great importance has been attached to natural disasters and related accidents in recent years, little attention has been paid to urban industrial accidents that constitute the biggest threat to cities. Urban disaster reduction should be given enough attention whether in developing large and medium-sized cities or promoting the construction of small towns in China. Attention should be paid not only to the research on the mechanism of industrial accidents,but also to industrial construction and disaster reduction planning and layout. This is of strategic importance to sustainable development.

  20. Automated data reduction workflows for astronomy

    CERN Document Server

    Freudling, W; Bramich, D M; Ballester, P; Forchi, V; Garcia-Dablo, C E; Moehler, S; Neeser, M J

    2013-01-01

    Data from complex modern astronomical instruments often consist of a large number of different science and calibration files, and their reduction requires a variety of software tools. The execution chain of the tools represents a complex workflow that needs to be tuned and supervised, often by individual researchers that are not necessarily experts for any specific instrument. The efficiency of data reduction can be improved by using automatic workflows to organise data and execute the sequence of data reduction steps. To realize such efficiency gains, we designed a system that allows intuitive representation, execution and modification of the data reduction workflow, and has facilities for inspection and interaction with the data. The European Southern Observatory (ESO) has developed Reflex, an environment to automate data reduction workflows. Reflex is implemented as a package of customized components for the Kepler workflow engine. Kepler provides the graphical user interface to create an executable flowch...