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Sample records for ozone treatment electronic

  1. Treatment of liquid separated from sludge by the method using electron beam and ozone in combination

    International Nuclear Information System (INIS)

    Hosono, Masakazu; Arai, Hidehiko; Aizawa, Masaki; Shimooka, Toshio; Shimizu, Ken; Sugiyama, Masashi.

    1995-01-01

    Since the liquid separated from sludge in the dehydration or concentration process of sewer sludge contains considerable amount of organic compositions that are hard to be decomposed by microorganisms, it has become difficult to be treated by conventional activated sludge process. In the case of discharging the separated liquid into closed water areas, the higher quality treatment is required. The method of using electron beam irradiation and ozone oxidation in combination for cleaning the liquid separated from sludge was examined, therefore, the results are reported. The water quality of the sample from the sludge treatment plant in A City is shown. The method of bio-pretreatment, the treatment method by using electron beam and ozone in combination, and the method of analyzing the water quality are described. The effect of the treatment by activated sludge process, as the effect of the treatment by the combined use of electron beam and ozone, the change of COD and TOC, the change of chromaticity, the change of gel chromatogram, and the reaction mechanism are reported. In this paper, only the basic concept on the model plant for applying the method of the combined use of electron beam and ozone to the treatment of the liquid separated from sludge is discussed. (K.I.)

  2. Ozone/electron beam process for water treatment: design, limitations and economic considerations

    International Nuclear Information System (INIS)

    Gehringer, P.; Eschweiler, H.

    1996-01-01

    Electron beam irradiation of water is the easiest way to generate OH free radicals but the efficiency of the irradiation process as advanced oxidation process (AOP) is deteriorated by reducing species formed simultaneously with the OH free radicals. Addition of ozone to the water before or during irradiation improves the efficiency essentially by converting the reducing species into OH free radicals and turning by that the irradiation process into a full AOP. The main reaction pathways of the primary species formed by the action of ionizing radiation on water in a natural groundwater with and without the presence of ozone are reviewed. Based on these data an explanation of both the dose rate effect and the ozone effect is attempted. New data is presented which illustrates the effect of alkalinity on the way in which ozone is introduced into the water, and the impact of both water matrix and chemical structure of the pollutants to the efficacy of the ozone/electron beam process. (author)

  3. Slow electrons kill the ozone

    International Nuclear Information System (INIS)

    Maerk, T.

    2001-01-01

    A new method and apparatus (Trochoidal electron monochromator) to study the interactions of electrons with atoms, molecules and clusters was developed. Two applications are briefly reported: a) the ozone destruction in the atmosphere is caused by different reasons, a new mechanism is proposed, that slow thermal electrons are self added to the ozone molecule (O 3 ) with a high frequency, then O 3 is destroyed ( O 3 + e - → O - + O 2 ); b) another application is the study of the binding energy of the football molecule C60. (nevyjel)

  4. Ozonation for source treatment of pharmaceuticals in hospital wastewater - ozone lifetime and required ozone dose

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Spiliotopoulou, Aikaterini; Chhetri, Ravi Kumar

    2016-01-01

    Ozonation aimed at removing pharmaceuticals was studied in an effluent from an experimental pilot system using staged moving bed biofilm reactor (MBBR) tanks for the optimal biological treatment of wastewater from a medical care unit of Aarhus University Hospital. Dissolved organic carbon (DOC......) and pH in samples varied considerably, and the effect of these two parameters on ozone lifetime and the efficiency of ozone in removing pharmaceuticals were determined. The pH in the effluent varied from 5.0 to 9.0 resulting in approximately a doubling of the required ozone dose at the highest p......H for each pharmaceutical. DOC varied from 6 to 20 mg-DOC/L. The ozone required for removing each pharmaceutical, varied linearly with DOC and thus, ozone doses normalized to DOC (specific ozone dose) agreed between water samples (typically within 15%). At neutral pH the specific ozone dose required...

  5. Dissociative electron attachment to ozone: rate constant

    International Nuclear Information System (INIS)

    Skalny, J.D.; Cicman, P.; Maerk, T.D.

    2002-01-01

    The rate constant for dissociative electron attachment to ozone has been derived over the energy range of 0-10 eV by using previously measured cross section data revisited here in regards to discrimination effect occurring during the extraction of ions. The obtained data for both possible channels exhibit the maximum at mean electron energies close to 1 eV. (author)

  6. Biologically resistant contaminants, primary treatment with ozone

    Energy Technology Data Exchange (ETDEWEB)

    Echegaray, Diego F. [White Martins Gases Industriais do Nordeste S.A., Salvador, BA (Brazil); Olivieri, Nadja F. [White Martins Gases Industriais S.A., Cordovil, RJ (Brazil)

    1993-12-31

    Organic effluent oxidation tests were conducted in petrochemical companies, in Camacari Petrochemical Complex (Northeast Brazil), to reduce treatment costs and improve the primary treatment efficiency in each industrial process. Ozone achieved 99.96 percent benzene reduction and 100 percent ethyl benzene and toluene reduction. Process efficiency is strongly dependent on the wastewater chemical composition and concentration. For this reason it is necessary to run pilot trials for each specific case. Ozone was obtained feeding commercial oxygen through a corona discharge generator and dissolved in the effluent with a bubble column. Commercial oxygen was used instead of air to increase 250 percent the ozone production, using the same ozone generator. (author). 4 figs., 2 tabs.

  7. Biologically resistant contaminants, primary treatment with ozone

    Energy Technology Data Exchange (ETDEWEB)

    Echegaray, Diego F [White Martins Gases Industriais do Nordeste S.A., Salvador, BA (Brazil); Olivieri, Nadja F [White Martins Gases Industriais S.A., Cordovil, RJ (Brazil)

    1994-12-31

    Organic effluent oxidation tests were conducted in petrochemical companies, in Camacari Petrochemical Complex (Northeast Brazil), to reduce treatment costs and improve the primary treatment efficiency in each industrial process. Ozone achieved 99.96 percent benzene reduction and 100 percent ethyl benzene and toluene reduction. Process efficiency is strongly dependent on the wastewater chemical composition and concentration. For this reason it is necessary to run pilot trials for each specific case. Ozone was obtained feeding commercial oxygen through a corona discharge generator and dissolved in the effluent with a bubble column. Commercial oxygen was used instead of air to increase 250 percent the ozone production, using the same ozone generator. (author). 4 figs., 2 tabs.

  8. Ozone treatment of textile wastewaters for reuse.

    Science.gov (United States)

    Ciardelli, G; Capannelli, G; Bottino, A

    2001-01-01

    Treatment of textile wastewaters by means of an ozonation pilot plant are described. Wastewaters used were produced by a dyeing and finishing factory and were first treated in an active sludge plant and filtrated through sand. In the appropriate conditions very high colour removal (95-99%) was achieved and the effluent could be reused in production processes requiring water of high quality as dyeing yarns or light colorations. Even if the chemical oxygen demand of treated waters was still in a range (75-120 mg/l, a decrease of up to 60%) that was usually considered to be too high for recycling purposes, recycling experiments were successful. The economical viability of the techniques implementation was also demonstrated and the industrial plant is currently under realisation under an EU financed project. The paper considers also the possible improvement of ozone diffusion by means of membrane contactors realised in a second pilot plant, in order to further reduce operating costs of the technique. With respect to traditional systems, the gas/liquid contact surface is much higher being that of the membrane. Ozone at the interface is therefore immediately solubilized and potentially consumed with no additional resistance to the mass transfer.

  9. Ozone-UV-catalysis based advanced oxidation process for wastewater treatment.

    Science.gov (United States)

    Tichonovas, Martynas; Krugly, Edvinas; Jankunaite, Dalia; Racys, Viktoras; Martuzevicius, Dainius

    2017-07-01

    A bench-scale advanced oxidation (AO) reactor was investigated for the degradation of six pollutants (2-naphthol, phenol, oxalic acid, phthalate, methylene blue, and D-glucose) in a model wastewater at with the aim to test opportunities for the further upscale to industrial applications. Six experimental conditions were designed to completely examine the experimental reactor, including photolysis, photocatalysis, ozonation, photolytic ozonation, catalytic ozonation, and photocatalytic ozonation. The stationary catalyst construction was made from commercially available TiO 2 nanopowder by mounting it on a glass support and subsequently characterized for morphology (X-ray diffraction analysis and scanning electron microscopy) as well as durability. The ozone was generated in a dielectrical barrier discharge reactor using air as a source of oxygen. The degradation efficiency was estimated by the decrease in total organic carbon (TOC) concentration as well as toxicity using Daphnia magna, and degradation by-products by ultra-performance liquid chromatography-mass spectrometry. The photocatalytic ozonation was the most effective for the treatment of all model wastewater. The photocatalytic ozonation was most effective against ozonation and photolytic ozonation at tested pH values. A complete toxicity loss was obtained after the treatment using photocatalytic ozonation. The possible degradation pathway of the phthalate by oxidation was suggested based on aromatic ring opening reactions. The catalyst used at this experiment confirmed as a durable for continuous use with almost no loss of activity over time. The design of the reactor was found to be very effective for water treatment using photocatalytic ozonation. Such design has a high potential and can be further upscaled to industrial applications due to the simplicity and versatility of manufacturing and maintenance.

  10. Minireview: the health implications of water treatment with ozone.

    Science.gov (United States)

    Carmichael, N G; Winder, C; Borges, S H; Backhouse, B L; Lewis, P D

    1982-01-11

    Ozone is a highly efficient disinfectant which may have significant advantages in water treatment compared to chlorine. It has, however, been shown that mutagenic and possibly carcinogenic byproducts may be produced under certain conditions of ozonation. Light chlorination following ozonization may meet the highest standards of disinfection. In addition the destruction of much of the organic matter by prior ozone treatment may well result in less harmful chlorinated and brominated products in the finished water. In many cases ozone treatment alone may suffice. It would be desirable to test with long term in vivo experiments which of the alternatives produces the best combination of microbiologically clean and pleasant water with minimum mutagenic and carcinogenic effect.

  11. Degradation and toxicity assessment of sulfamethoxazole and chlortetracycline using electron beam, ozone and UV

    International Nuclear Information System (INIS)

    Kim, Tae-Hun; Kim, Sang Don; Kim, Hyun Young; Lim, Seung Joo; Lee, Myunjoo; Yu, Seungho

    2012-01-01

    Highlights: ► The degradation efficiency and trends for antibiotics were different between AOPs. ► The toxicities of target antibiotics were mainly affected by parent compounds. ► E-beam was electrically more energy efficient than ozone and UV-C. ► Application of AOPs should be considered according to the types of pharmaceuticals. - Abstract: Recently, the occurrence of antibiotics in sewage treatment plant effluent, as well as drinking water, has raised concern about their potential impacts on the environment and public health. Antibiotics are found in surface and ground waters, which indicate their ineffective removal by conventional wastewater treatment processes. Therefore, advanced oxidation processes (AOPs) have received considerable attention for the removal of antibiotics. This study was conducted to evaluate the degradation and mineralization of antibiotics (sulfamethoxazole and chlortetracycline) using an electron beam, ozone and UV, and the change of toxicity. Also, the electrical energy consumption based on the EE/O parameter (the electrical energy required per order of pollutants removal in 1 m 3 wastewater) was used to quantify the energy cost associated with the different AOPs (electron beam, ozone and UV) for the degradation of antibiotics. The results showed that an electron beam effective for the removals of both sulfamethoxazole and chlortetracycline in aqueous solutions. However, degradation of the target compounds by ozone and UV showed different trends. The oxidation efficiency of each organic compound was very dependent upon the AOP used. Algal toxicity was significantly reduced after each treatment. However, based on the electrical energy, the electron beam was more efficient than ozone and UV. Electron beam treatment could be an effective and safe method for the removal of antibiotic compounds.

  12. Greater Vancouver's water supply receives ozone treatment

    Energy Technology Data Exchange (ETDEWEB)

    Crosby, J.; Singh, I.; Reil, D. D.; Neden, G.

    2000-10-01

    To improve the overall quality of the treated water delivered to the member municipalities of the Greater Vancouver Water District (GVWD), the GVWD implemented a phased drinking water quality improvement program. The phased treatment program is directed at attaining effective disinfection while minimizing the formation of chlorinated disinfection by-products. Accordingly, the current primary disinfection method of chlorination was reevaluated and an ozone primary disinfection without filtration was authorized. Ozonization provides increased protection against Giardia and Cryptosporidium and a decrease in the formation potential for disinfection by-products (DPBs). This paper describes the design for the ozonation facility at Coquitlam, construction of which began in 1998 and completed during the summer of 2000. The facility houses the liquid oxygen supply, ozone generation, cooling water, ozone injection, primary off-gas ozone destruct system, and provides a home for various office, electrical maintenance and diesel generating functions. The second site at Capilano is expected to start construction in the fall of 2000 and be completed late in 2002. Wit its kilometre long stainless steel ozone contactor and sidestream injector tower, the Coquitlam Ozonation Facility is the first ozone pressure injection system of its kind in North America. 1 tab., 2 figs.

  13. Combined treatment of mezcal vinasses by ozonation and activated sludge.

    Science.gov (United States)

    2017-10-18

    In Mexico, mezcal production generates huge amounts of vinasses (MV) that cause negative environmental impacts. Thus, MV treatment is necessary before discharge to water bodies. Although there is no information for mezcal vinasses, similar effluents have been treated by biological processes (i.e. anaerobic and aerobic) usually complemented by oxidative chemical pretreatments (ozonation) and physico-chemical methods. In this work MV were first ozonated and followed by batch aerobic biological degradation. In the ozonation stage, organic matter removals were 4.5-11 % as COD, whereas the removal of aromatic compounds and phenols were 16-32 % and 48-83 % respectively. In the aerobic post-treatment, COD depletions up to 85 % were achieved; removals in ozone pre-treated vinasses were higher (80 to 85 %) than that of raw vinasse (69 %). It seems that ozonation preferentially attacked the recalcitrant fraction of organic matter present in the vinasses and increased its aerobic biodegradability.

  14. Improved functionality of graphene and carbon nanotube hybrid foam architecture by UV-ozone treatment

    Science.gov (United States)

    Wang, Wei; Ruiz, Isaac; Lee, Ilkeun; Zaera, Francisco; Ozkan, Mihrimah; Ozkan, Cengiz S.

    2015-04-01

    Optimization of the electrode/electrolyte double-layer interface is a key factor for improving electrode performance of aqueous electrolyte based supercapacitors (SCs). Here, we report the improved functionality of carbon materials via a non-invasive, high-throughput, and inexpensive UV generated ozone (UV-ozone) treatment. This process allows precise tuning of the graphene and carbon nanotube hybrid foam (GM) transitionally from ultrahydrophobic to hydrophilic within 60 s. The continuous tuning of surface energy can be controlled by simply varying the UV-ozone exposure time, while the ozone-oxidized carbon nanostructure maintains its integrity. Symmetric SCs based on the UV-ozone treated GM foam demonstrated enhanced rate performance. This technique can be readily applied to other CVD-grown carbonaceous materials by taking advantage of its ease of processing, low cost, scalability, and controllability.Optimization of the electrode/electrolyte double-layer interface is a key factor for improving electrode performance of aqueous electrolyte based supercapacitors (SCs). Here, we report the improved functionality of carbon materials via a non-invasive, high-throughput, and inexpensive UV generated ozone (UV-ozone) treatment. This process allows precise tuning of the graphene and carbon nanotube hybrid foam (GM) transitionally from ultrahydrophobic to hydrophilic within 60 s. The continuous tuning of surface energy can be controlled by simply varying the UV-ozone exposure time, while the ozone-oxidized carbon nanostructure maintains its integrity. Symmetric SCs based on the UV-ozone treated GM foam demonstrated enhanced rate performance. This technique can be readily applied to other CVD-grown carbonaceous materials by taking advantage of its ease of processing, low cost, scalability, and controllability. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr06795a

  15. Application of Ozone MBBR Process in Refinery Wastewater Treatment

    Science.gov (United States)

    Lin, Wang

    2018-01-01

    Moving Bed Biofilm Reactor (MBBR) is a kind of sewage treatment technology based on fluidized bed. At the same time, it can also be regarded as an efficient new reactor between active sludge method and the biological membrane method. The application of ozone MBBR process in refinery wastewater treatment is mainly studied. The key point is to design the ozone +MBBR combined process based on MBBR process. The ozone +MBBR process is used to analyze the treatment of concentrated water COD discharged from the refinery wastewater treatment plant. The experimental results show that the average removal rate of COD is 46.0%~67.3% in the treatment of reverse osmosis concentrated water by ozone MBBR process, and the effluent can meet the relevant standard requirements. Compared with the traditional process, the ozone MBBR process is more flexible. The investment of this process is mainly ozone generator, blower and so on. The prices of these items are relatively inexpensive, and these costs can be offset by the excess investment in traditional activated sludge processes. At the same time, ozone MBBR process has obvious advantages in water quality, stability and other aspects.

  16. Application of ozone in the treatment of periodontal disease

    Science.gov (United States)

    Srikanth, Adusumilli; Sathish, Manthena; Sri Harsha, Anumolu Venkatanaga

    2013-01-01

    Gingivitis and periodontitis are most common inflammatory diseases of supporting tissues of teeth. Role of microbial etiology and host response in progression of gingival and periodontal diseases has been well established. Because of the beneficial biological effects of ozone, due to its antimicrobial and immunostimulating effect, it is well indicated in the treatment of gingival and periodontal diseases. The objective of this article is to provide a general review about clinical applications of ozone in treatment of periodontal diseases and to summarize the available in vitro and in vivo studies in Periodontics in which ozone has been used. PMID:23946585

  17. Modelling the Ozone-Based Treatments for Inactivation of Microorganisms

    Directory of Open Access Journals (Sweden)

    Agnieszka Joanna Brodowska

    2017-10-01

    Full Text Available The paper presents the development of a model for ozone treatment in a dynamic bed of different microorganisms (Bacillus subtilis, B. cereus, B. pumilus, Escherichia coli, Pseudomonas fluorescens, Aspergillus niger, Eupenicillium cinnamopurpureum on a heterogeneous matrix (juniper berries, cardamom seeds initially treated with numerous ozone doses during various contact times was studied. Taking into account various microorganism susceptibility to ozone, it was of great importance to develop a sufficiently effective ozone dose to preserve food products using different strains based on the microbial model. For this purpose, we have chosen the Weibull model to describe the survival curves of different microorganisms. Based on the results of microorganism survival modelling after ozone treatment and considering the least susceptible strains to ozone, we selected the critical ones. Among tested strains, those from genus Bacillus were recognized as the most critical strains. In particular, B. subtilis and B. pumilus possessed the highest resistance to ozone treatment because the time needed to achieve the lowest level of its survival was the longest (up to 17.04 min and 16.89 min for B. pumilus reduction on juniper berry and cardamom seed matrix, respectively. Ozone treatment allow inactivate microorganisms to achieving lower survival rates by ozone dose (20.0 g O3/m3 O2, with a flow rate of 0.4 L/min and contact time (up to 20 min. The results demonstrated that a linear correlation between parameters p and k in Weibull distribution, providing an opportunity to calculate a fitted equation of the process.

  18. Modelling the Ozone-Based Treatments for Inactivation of Microorganisms

    Science.gov (United States)

    Brodowska, Agnieszka Joanna; Nowak, Agnieszka; Kondratiuk-Janyska, Alina; Piątkowski, Marcin; Śmigielski, Krzysztof

    2017-01-01

    The paper presents the development of a model for ozone treatment in a dynamic bed of different microorganisms (Bacillus subtilis, B. cereus, B. pumilus, Escherichia coli, Pseudomonas fluorescens, Aspergillus niger, Eupenicillium cinnamopurpureum) on a heterogeneous matrix (juniper berries, cardamom seeds) initially treated with numerous ozone doses during various contact times was studied. Taking into account various microorganism susceptibility to ozone, it was of great importance to develop a sufficiently effective ozone dose to preserve food products using different strains based on the microbial model. For this purpose, we have chosen the Weibull model to describe the survival curves of different microorganisms. Based on the results of microorganism survival modelling after ozone treatment and considering the least susceptible strains to ozone, we selected the critical ones. Among tested strains, those from genus Bacillus were recognized as the most critical strains. In particular, B. subtilis and B. pumilus possessed the highest resistance to ozone treatment because the time needed to achieve the lowest level of its survival was the longest (up to 17.04 min and 16.89 min for B. pumilus reduction on juniper berry and cardamom seed matrix, respectively). Ozone treatment allow inactivate microorganisms to achieving lower survival rates by ozone dose (20.0 g O3/m3 O2, with a flow rate of 0.4 L/min) and contact time (up to 20 min). The results demonstrated that a linear correlation between parameters p and k in Weibull distribution, providing an opportunity to calculate a fitted equation of the process. PMID:28991199

  19. A Comparative Electrochemical-Ozone Treatment for Removal of Phenolphthalein

    Directory of Open Access Journals (Sweden)

    V. M. García-Orozco

    2016-01-01

    Full Text Available The degradation of aqueous solutions containing phenolphthalein was carried out using ozone and electrochemical processes; the two different treatments were performed for 60 min at pH 3, pH 7, and pH 9. The electrochemical oxidation using boron-doped diamond electrodes processes was carried out using three current density values: 3.11 mA·cm−2, 6.22 mA·cm−2, and 9.33 mA·cm−2, whereas the ozone dose was constantly supplied at 5±0.5 mgL−1. An optimal degradation condition for the ozonation treatment is at alkaline pH, while the electrochemical treatment works better at acidic pH. The electrochemical process is twice better compared with ozonation.

  20. Effect of calcium-ozone treatment on chemical and biological properties of polyethylene terephthalate.

    Science.gov (United States)

    Rashid, Ahmed Nafis; Tsuru, Kanji; Ishikawa, Kunio

    2015-05-01

    Ozone (O3 ) treatment of polyethylene terephthalate (PET) in distilled water was performed in the presence and absence of calcium (Ca(2+) ). PET was oxidized and thus carboxylic and hydroxyl functional groups were introduced on its surface after O3 treatment, regardless of the presence or absence of Ca(2+) . In the case of O3 treatment with Ca(2+) , PET surface was modified with Ca(2+) . Ca(2+) immobilization was confirmed by X-ray photoelectron spectrometric analysis. Hydrophilicity was investigated by measuring contact angles (CA). CA of PET decreased significantly after ozonation. Surface topography of PET before and after ozone treatment was observed by scanning electron microscopy, and showed no morphological changes. In vitro studies showed enhanced rat bone marrow cell responses on the O3 -treated PET surface. Ca(2+) -O3 oxidation at 37°C for 6 h is expected to be an effective method to fabricate PET with good biocompatibility. © 2014 Wiley Periodicals, Inc.

  1. Ozone in the food industry: Principles of ozone treatment, mechanisms of action, and applications: An overview.

    Science.gov (United States)

    Brodowska, Agnieszka Joanna; Nowak, Agnieszka; Śmigielski, Krzysztof

    2017-04-10

    The food contamination issue requires continuous control of food at each step of the production process. High quality and safety of products are equally important factors in the food industry. They may be achieved with several, more or less technologically advanced methodologies. In this work, we review the role, contribution, importance, and impact of ozone as a decontaminating agent used to control and eliminate the presence of microorganisms in food products as well as to extend their shelf-life and remove undesirable odors. Several researchers have been focusing on the ozone's properties and applications, proving that ozone treatment technology can be applied to all types of foods, from fruits, vegetables, spices, meat, and seafood products to beverages. A compilation of those works, presented in this review, can be a useful tool for establishing appropriate ozone treatment conditions, and factors affecting the improved quality and safety of food products. A critical evaluation of the advantages and disadvantages of ozone in the context of its application in the food industry is presented as well.

  2. Advanced treatment of biotreated textile industry wastewater with ozone, virgin/ozonated granular activated carbon and their combination.

    Science.gov (United States)

    Arslan-Alaton, Idil; Seremet, Ozden

    2004-01-01

    Biotreated textile wastewater (CODo = 248 mg L(-1); TOCo = 58 mg L(-1); A620 = 0.007 cm(-1); A525 = 0.181 cm(-1); A436 = 0.198 cm(-1)) was subjected to advanced treatment with ozonation, granular activated carbon (GAC) adsorption in serial and simultaneous applications. Experiments were conducted to investigate the effects of applied ozone dose, ozone absorption rate, specific ozone absorption efficiency, GAC dose, and reaction pH on the treatment performance of the selected tertiary treatment scheme. In separate experiments, the impact of virgin GAC ozonation on its adsorptive capacity for biotreated and biotreated + ozonated textile effluent was also investigated. Ozonation appeared to be more effective for decolorization (kd = 0.15 min(-1) at pH = 3), whereas GAC adsorption yielded higher COD removal rates (54% at pH = 3). It was also found that GAC addition (4 g/L) at pH = 7 and 9 enhanced the COD abatement rate of the ozonation process significantly and that the sequential application of ozonation (at pH = 3-11, 675 mg L(-1) O3) followed by GAC adsorption (at pH = 3-7, 10 g L(-1) GAC) resulted in the highest treatment performances both in terms of color and COD reduction. Simultaneous application of GAC and ozone at acidic and alkaline pH seriously inhibited COD abatement rates as a consequence of competitive adsorption and partial oxidation of textile components and GAC. It could also be established that ozone absorption efficiency decreased after color removal was complete. Ozonation of biotreated textile wastewater with 113 mg L(-1) ozone resulted in an appreciable enhancement of GAC adsorptive capacity in terms of residual color removal. Ozonation of GAC at relatively low doses (= 10.8 mg/g GAC) did not improve its overall adsorption capacity.

  3. OZONE TREATMENT OF SOLUBLE ORGANICS IN PRODUCED WATER

    Energy Technology Data Exchange (ETDEWEB)

    Klasson, KT

    2002-03-14

    This project was an extension of previous research to improve the applicability of ozonation and will help address the petroleum-industry problem of treating produced water containing soluble organics. The goal of this project was to maximize oxidation of hexane-extractable organics during a single-pass operation. The project investigated: (1) oxidant production by electrochemical and sonochemical methods, (2) increasing the mass transfer rate in the reactor by forming microbubbles during ozone injection into the produced water, and (3) using ultraviolet irradiation to enhance the reaction if needed. Several types of methodologies for treatment of soluble organics in synthetic and actual produced waters have been performed. The technologies tested may be categorized as follows: (1) Destruction via sonochemical oxidation at different pH, salt concentration, ultraviolet irradiation, and ferrous iron concentrations. (2) Destruction via ozonation at different pH, salt concentration, hydrogen peroxide concentrations, ultraviolet irradiation, temperature, and reactor configurations.

  4. Treatment of Wastewater by Ozone Produced in Dielectric Barrier Discharge

    Directory of Open Access Journals (Sweden)

    Rita Bhatta

    2015-01-01

    Full Text Available There is rapid diminishing of water resources in many countries due to, for example, population growth and constant reduction in fresh water supply. The sewage wastewater, industrial effluents, and municipal wastewater are directly and indiscriminately discharged into rivers and lakes and thus primarily cause water pollution in Nepal. This has increased the water crisis and also causes environmental deterioration. Therefore, the need for the development of an effective, cheap, and environmentally friendly process for the treatment of wastewater before discharging into aquatic environment has emerged. Treatment by ozone produced from dielectric barrier discharge is one of the emerging technologies for such application. The ozonation process is more effective for disinfection and degradation of organic pollutants from water. The current study describes the treatment of wastewater of selected site within Kathmandu. Results on various physicochemical and microbial parameters of the inlet and outlet samples are discussed. Our results showed slight increase in pH, decrease in chemical oxygen demand, and significant increase in dissolved oxygen after ozonation. Importantly, ozonation caused total reduction of fecal coliform.

  5. Combination of ozonation and photocatalysis for pharmaceutical wastewater treatment

    Science.gov (United States)

    Ratnawati, Enjarlis, Slamet

    2017-11-01

    The chemical oxygen demand (COD) and phenol removal from pharmaceutical wastewater were investigated using configuration of two circulation batch reactors in a series with ozonation and photocatalytic processes. The ozonation is conducted with O3/granulated activated carbon (O3/GAC), whereas photocatalysis with TiO2 that immobilized on pumice stone (PS-TiO2). The effect of circulation flow rate (10; 12; 15 L/min) and the amount PS-TiO2 (200 g, 250 g, 300 g) were examined. Wastewater of 20 L was circulated pass through the pipe that injected with O3 by the ozone generator, and subsequently flow through two GAC columns, and finally, go through photoreactor that contains photocatalyst PS-TiO2 which equipped with mercury lamp as a photon source. At a time interval, COD and phenol concentration were measured to assess the performance of the process. FESEM imaging confirmed that TiO2 was successfully impregnated on PS, as corroborated by EDX spectra. Meanwhile, degradation process indicated that the combined ozonation and photocatalytic processes (O3/GAC-TiO2) is more efficient compared to the ozonation and photocatalysis alone. For combination process with the circulation flow rate of 10 L/min and 300 g of PS-TiO2,the influent COD of around 1000 ppm are effectively degraded to a final effluent COD of 290 ppm (71% removal) and initial phenol concentration of 4.75 ppm down to 0 ppm for 4 h which this condition fulfill the discharge standards quality. Therefore, this portable prototype reactor is effective that can be used in the pharmaceutical wastewater treatment. For the future, this process condition will be developed for orientation on the industrial applications (portable equipment) since pharmaceutical industries produce wastewater relatively in the small amount.

  6. Microbubble enhanced ozonation process for advanced treatment of wastewater produced in acrylic fiber manufacturing industry

    KAUST Repository

    Zheng, Tianlong

    2015-02-02

    This work investigated microbubble-ozonation for the treatment of a refractory wet-spun acrylic fiber wastewater in comparison to macrobubble-ozonation. CODcr, NH3-N, and UV254 of the wastewater were removed by 42%, 21%, and 42%, respectively in the microbubble-ozonation, being 25%, 9%, and 35% higher than the removal rates achieved by macrobubble-ozonation at the same ozone dose. The microbubbles (with average diameter of 45μm) had a high concentration of 3.9×105 counts/mL at a gas flow rate of 0.5L/min. The gas holdup, total ozone mass-transfer coefficient, and average ozone utilization efficiency in the microbubble-ozonation were 6.6, 2.2, and 1.5 times higher than those of the macrobubble-ozonation. Greater generation of hydroxyl radicals and a higher zeta potential of the bubbles were also observed in the microbubble ozonation process. The biodegradability of the wastewater was also significantly improved by microbubble-ozonation, which was ascribed to the enhanced degradation of alkanes, aromatic compounds, and the many other bio-refractory organic compounds in the wastewater. Microbubble-ozonation can thus be a more effective treatment process than traditional macrobubble-ozonation for refractory wastewater produced by the acrylic fiber manufacturing industry.

  7. Wastewater purification. Combined electron-beam and ozone action in the aerosol flow

    International Nuclear Information System (INIS)

    Podzorova, E.A.; Pikaev, A.K.

    1998-01-01

    Complete text of publication follows. Ozone is forming with high enough radiation chemical yield during work of electron accelerator. It is useful to use oxidizing properties of ozone with combination of ionizing radiation. The combined action of ionized radiation and ozone on aqueous solutions increases efficiency of water purification. But at the same time, this kind process of water purification is characterized by some limited stages: 1. Ozone mass transfer rate from gaseous phase (where it is formed) into liquid phase (where pollutants present); 2. Small solubility ozone in water; 3. High rate constant of radiation induced decomposition of ozone. We have proposed some optimizations for this kind of process. The most effective action of ionized radiation and radiolytic ozone on polluted water is running this process in aerosol flow. The highly developed surface of phase division is provided the maximum rate of reaction of ozone with pollutants. The volatile pollutants react with radiolytic ozone in gaseous phase in ozone creation moment. Ozonoradiolysis of real municipal wastewater in an aerosol flow was investigated on a facility with electron accelerator with electron energy E=0,3 MeV, power up to 15 kWatt, productivity 500 m 3 /day. Density of the irradiated aerosol was 0,02-0,05 g/cm 3 . It is increase low-energy electron range on 1-2 orders of magnitude as compared with liquid water and increases effective depth of uniformed irradiated layer. Because aerosol density is much higher compare with air density, it is clear, that water drops in aerosol flow absorbed main energy. The treated municipal wastewater in this facility was cleaned from organic and inorganic pollutants. COD and BOD values were reduced. Water disinfecting is achieved to sanitary standards

  8. Electroplating wastewater treatment by the combined electrochemical and ozonation methods.

    Science.gov (United States)

    Orescanin, Visnja; Kollar, Robert; Mikelic, Ivanka Lovrencic; Nad, Karlo

    2013-01-01

    This article presents a pilot-plant study of the electroplating wastewater treatment by the processes of electroreduction with iron electrode plates, and electrocoagulation/ozonation with aluminum electrode set, followed by the process of ozonation. The initial effluent was found to be highly enriched in heavy metals and to possess the elevated levels of organic contaminants. The values of Cr(VI), Fe, Ni, Cu, Zn, Pb, TOC, and COD exceeded the upper permissible limits of 63, 220.2, 1.1, 7, 131.3, 1.7, 12.3, and 11.4 times, respectively. The heavy metal removal was forced either by the coagulation/flocculation using Fe(II), Fe(III), and Al(III) ions released into the treated solution by the electrochemical corrosion of the sacrificial iron and aluminum electrodes, or the precipitation of the metal hydroxides as well as co-precipitation with iron and aluminum hydroxides. The principle organic matter destruction mechanisms were ozone oxidation and the indirect oxidation with chlorine/hypochlorite formed by the anodic oxidation of chloride already present in the wastewater. Following the combined treatment, the removal efficiencies of Cr(VI), Fe, Ni, Cu, Zn, Pb, TOC, and COD were 99.94%, 100.00%, 95.86%, 98.66%, 99.97%, 96.81%, 93.24%, and 93.43%, respectively, thus complying with the regulated values.

  9. Treatment of micropollutants in municipal wastewater: Ozone or powdered activated carbon?

    International Nuclear Information System (INIS)

    Margot, Jonas; Kienle, Cornelia; Magnet, Anoÿs; Weil, Mirco; Rossi, Luca; Alencastro, Luiz Felippe de; Abegglen, Christian; Thonney, Denis; Chèvre, Nathalie; Schärer, Michael

    2013-01-01

    Many organic micropollutants present in wastewater, such as pharmaceuticals and pesticides, are poorly removed in conventional wastewater treatment plants (WWTPs). To reduce the release of these substances into the aquatic environment, advanced wastewater treatments are necessary. In this context, two large-scale pilot advanced treatments were tested in parallel over more than one year at the municipal WWTP of Lausanne, Switzerland. The treatments were: i) oxidation by ozone followed by sand filtration (SF) and ii) powdered activated carbon (PAC) adsorption followed by either ultrafiltration (UF) or sand filtration. More than 70 potentially problematic substances (pharmaceuticals, pesticides, endocrine disruptors, drug metabolites and other common chemicals) were regularly measured at different stages of treatment. Additionally, several ecotoxicological tests such as the Yeast Estrogen Screen, a combined algae bioassay and a fish early life stage test were performed to evaluate effluent toxicity. Both treatments significantly improved the effluent quality. Micropollutants were removed on average over 80% compared with raw wastewater, with an average ozone dose of 5.7 mg O 3 l −1 or a PAC dose between 10 and 20 mg l −1 . Depending on the chemical properties of the substances (presence of electron-rich moieties, charge and hydrophobicity), either ozone or PAC performed better. Both advanced treatments led to a clear reduction in toxicity of the effluents, with PAC-UF performing slightly better overall. As both treatments had, on average, relatively similar efficiency, further criteria relevant to their implementation were considered, including local constraints (e.g., safety, sludge disposal, disinfection), operational feasibility and cost. For sensitive receiving waters (drinking water resources or recreational waters), the PAC-UF treatment, despite its current higher cost, was considered to be the most suitable option, enabling good removal of most

  10. Stratospheric ozone conservation by electron attachment to chlorine atoms: The negative-ion chemistry

    International Nuclear Information System (INIS)

    Ho, D.D.M.; Tsang, K.T.; Wong, A.Y.; Siverson, R.J.

    1990-01-01

    Creating low-energy electrons in the stratosphere by photoelectric emission has the beneficial effect of suppressing ozone destruction by Cl. This is because Cl is converted to Cl - , which is less reactive. Critical to the success of this scheme is the ability to attach most of the electrons to Cl - and its hydrates Cl - (H 2 O). We found that this attachment efficiency is rather high. This is remarkable given the fact that the electron affinity of Cl - is less than that of NO 3 -. Photoddetachment of NO 3 - is the key factor that leads to this high efficiency. Computer calculations show that ozone increases with electron injection, and most of the electrons end up attaching to Cl - (H 2 O). We also point out that 40 km, the altitude at which most of the ozone destruction occurs, is also the optimum altitude for injecting photoelectric electrons. 12 refs., 6 figs

  11. Post-treatment of Fly Ash by Ozone in a Fixed Bed Reactor

    DEFF Research Database (Denmark)

    Pedersen, Kim Hougaard; Melia, M. C.; Jensen, Anker Degn

    2009-01-01

    to be fast. A kinetic model has been formulated, describing the passivation of carbon, and it includes the stoichiometry of the ozone consumption (0.8 mol of O-3/kg of C) and an ineffective ozone loss caused by catalytic decomposition. The simulated results correlated well with the experimental data....... prevents the AEA to be adsorbed. In the present work, two fly ashes have been ozonated in a fixed bed reactor and the results showed that ozonation is a potential post-treatment method that can lower the AEA requirements of a fly ash up to 6 times. The kinetics of the carbon oxidation by ozone was found...

  12. Industrial wastewater advanced treatment via catalytic ozonation with an Fe-based catalyst.

    Science.gov (United States)

    Li, Xufang; Chen, Weiyu; Ma, Luming; Wang, Hongwu; Fan, Jinhong

    2018-03-01

    An Fe-based catalyst was used as a heterogeneous catalyst for the ozonation of industrial wastewater, and key operational parameters (pH and catalyst dosage) were studied. The results indicated that the Fe-based catalyst significantly improved the mineralization of organic pollutants in wastewater. TOC (total organic carbon) removal was high, at 78.7%, with a catalyst concentration of 200 g/L, but only 31.6% with ozonation alone. The Fe-based catalyst significantly promoted ozone decomposition by 70% in aqueous solution. Hydroxyl radicals (·OH) were confirmed to be existed directly via EPR (electron paramagnetic resonance) experiments, and ·OH were verified to account for about 34.4% of TOC removal with NaHCO 3 as a radical scavenger. Through characterization by SEM-EDS (field emission scanning electron microscope with energy-dispersive spectrometer), XRD (X-ray powder diffraction) and XPS (X-ray photoelectron spectroscopy), it was deduced that FeOOH on the surface of the catalyst was the dominant contributor to the catalytic efficiency. The catalyst was certified as having good stability and excellent reusability based on 50 successive operations and could be used as a filler simultaneously. Thereby, it is a promising catalyst for practical industrial wastewater advanced treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Solar photo-ozonation: A novel treatment method for the degradation of water pollutants

    International Nuclear Information System (INIS)

    Chávez, Ana M.; Rey, Ana; Beltrán, Fernando J.; Álvarez, Pedro M.

    2016-01-01

    Highlights: • Aqueous ozone decomposition is accelerated by solar radiation. • Hydrogen peroxide is identifies as a main intermediate of decomposition of aqueous ozone under solar irradiation. • Solar photo-ozonation leads to higher Rct ratios than single ozonation. • Solar photo-ozonation is a promising AOP for the degradation of water pollutants. - Abstract: The decomposition of aqueous ozone by UV–vis radiation has been investigated with focus on the impact of ozone photolysis on the degradation of water pollutants during solar ozonation processes. The apparent first-order rate constants of the decomposition of ozone (k_o_b_s) have been determined at various pHs in the 4–9 range using radiation of different wavelengths in the UV–vis range. It was found that UVA–visible radiation (λ > 320 nm) highly enhanced ozone decomposition, especially at pH 4, for which k_o_b_s was three-folded with respect to the process in the absence of radiation. Hydrogen peroxide was identified as a main intermediate of ozone photo-decomposition at pH 4. Experiments of degradation of oxalic acid by ozone showed that solar irradiation brings about an increase in the hydroxyl radical to ozone exposures ratio (R_c_t). Finally, photo-ozonation (λ > 300 nm) was shown advantageous over single ozonation in the mineralization of a selection of emerging contaminants (metoprolol, ibuprofen, N,N-diethyl-meta-toluamide and clofibric acid) in both ultrapure water and a synthetic secondary effluent. Thus, TOC removal in 2-h treatments increased from 10 to 25% in the absence of radiation to about 50% in the presence of radiation.

  14. Solar photo-ozonation: A novel treatment method for the degradation of water pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Chávez, Ana M.; Rey, Ana; Beltrán, Fernando J.; Álvarez, Pedro M., E-mail: pmalvare@unex.es

    2016-11-05

    Highlights: • Aqueous ozone decomposition is accelerated by solar radiation. • Hydrogen peroxide is identifies as a main intermediate of decomposition of aqueous ozone under solar irradiation. • Solar photo-ozonation leads to higher Rct ratios than single ozonation. • Solar photo-ozonation is a promising AOP for the degradation of water pollutants. - Abstract: The decomposition of aqueous ozone by UV–vis radiation has been investigated with focus on the impact of ozone photolysis on the degradation of water pollutants during solar ozonation processes. The apparent first-order rate constants of the decomposition of ozone (k{sub obs}) have been determined at various pHs in the 4–9 range using radiation of different wavelengths in the UV–vis range. It was found that UVA–visible radiation (λ > 320 nm) highly enhanced ozone decomposition, especially at pH 4, for which k{sub obs} was three-folded with respect to the process in the absence of radiation. Hydrogen peroxide was identified as a main intermediate of ozone photo-decomposition at pH 4. Experiments of degradation of oxalic acid by ozone showed that solar irradiation brings about an increase in the hydroxyl radical to ozone exposures ratio (R{sub ct}). Finally, photo-ozonation (λ > 300 nm) was shown advantageous over single ozonation in the mineralization of a selection of emerging contaminants (metoprolol, ibuprofen, N,N-diethyl-meta-toluamide and clofibric acid) in both ultrapure water and a synthetic secondary effluent. Thus, TOC removal in 2-h treatments increased from 10 to 25% in the absence of radiation to about 50% in the presence of radiation.

  15. Ozone treatment of textile wastewater relevant to toxic effect elimination in marine environment

    OpenAIRE

    Guendy, H.R.

    2007-01-01

    Ozone is a powerful oxidizing agent. The reaction of ozone with organic compounds in aqueous media has achieved a variety of treatment goals. The advantage of ozonation over the other oxidants is that the degradable products of ozonation are generally non-toxic, its final products are CO2 and H2O, and also the residual O3 in the system changes in few minutes to O2 .Convential treatment of textile wastewater includes various combinations of biological (activated sludge), physical and chemical ...

  16. Combined anaerobic–ozonation process for treatment of textile wastewater: Removal of acute toxicity and mutagenicity

    Energy Technology Data Exchange (ETDEWEB)

    Punzi, Marisa, E-mail: marisa.punzi@biotek.lu.se [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Nilsson, Filip [Water and Environmental Engineering at the Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Anbalagan, Anbarasan [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Svensson, Britt-Marie [School of Education and Environment, Kristianstad University, SE-291 88 Kristianstad (Sweden); Jönsson, Karin [Water and Environmental Engineering at the Department of Chemical Engineering, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden); Mattiasson, Bo; Jonstrup, Maria [Department of Biotechnology, Lund University, P.O. Box 124, SE-221 00 Lund (Sweden)

    2015-07-15

    Highlights: • COD and UV absorbance were effectively reduced. • The treated effluents were non-toxic to Artemia salina and Vibrio fischeri. • The real textile wastewater was mutagenic. • Mutagenicity persisted after bio treatment and even more after a short ozonation. • Higher ozone doses completely remove mutagenicity. - Abstract: A novel set up composed of an anaerobic biofilm reactor followed by ozonation was used for treatment of artificial and real textile effluents containing azo dyes. The biological treatment efficiently removed chemical oxygen demand and color. Ozonation further reduced the organic content of the effluents and was very important for the degradation of aromatic compounds, as shown by the reduction of UV absorbance. The acute toxicity toward Vibrio fischeri and the shrimp Artemia salina increased after the biological treatment. No toxicity was detected after ozonation with the exception of the synthetic effluent containing the highest concentration, 1 g/l, of the azo dye Remazol Red. Both untreated and biologically treated textile effluents were found to have mutagenic effects. The mutagenicity increased even further after 1 min of ozonation. No mutagenicity was however detected in the effluents subjected to longer exposure to ozone. The results of this study suggest that the use of ozonation as short post-treatment after a biological process can be beneficial for the degradation of recalcitrant compounds and the removal of toxicity of textile wastewater. However, monitoring of toxicity and especially mutagenicity is crucial and should always be used to assess the success of a treatment strategy.

  17. Ultraviolet-ozone treatment reduces levels of disease-associated prion protein and prion infectivity

    Science.gov (United States)

    Johnson, C.J.; Gilbert, P.; McKenzie, D.; Pedersen, J.A.; Aiken, Judd M.

    2009-01-01

    Background. Transmissible spongiform encephalopathies (TSEs) are a group of fatal neurodegenerative diseases caused by novel infectious agents referred to as prions. Prions appear to be composed primarily, if not exclusively, of a misfolded isoform of the cellular prion protein. TSE infectivity is remarkably stable and can resist many aggressive decontamination procedures, increasing human, livestock and wildlife exposure to TSEs. Findings. We tested the hypothesis that UV-ozone treatment reduces levels of the pathogenic prion protein and inactivates the infectious agent. We found that UV-ozone treatment decreased the carbon and prion protein content in infected brain homogenate to levels undetectable by dry-ashing carbon analysis or immunoblotting, respectively. After 8 weeks of ashing, UV-ozone treatment reduced the infectious titer of treated material by a factor of at least 105. A small amount of infectivity, however, persisted despite UV-ozone treatment. When bound to either montmorillonite clay or quartz surfaces, PrPTSE was still susceptible to degradation by UV-ozone. Conclusion. Our findings strongly suggest that UV-ozone treatment can degrade pathogenic prion protein and inactivate prions, even when the agent is associated with surfaces. Using larger UV-ozone doses or combining UV-ozone treatment with other decontaminant methods may allow the sterilization of TSE-contaminated materials. ?? 2009 Aiken et al; licensee BioMed Central Ltd.

  18. Advanced treatment of acrylic fiber manufacturing wastewater with a combined microbubble-ozonation/ultraviolet irradiation process

    KAUST Repository

    Zheng, Tianlong; Zhang, Tao; Wang, Qunhui; Tian, Yanli; Shi, Zhining; Smale, Nicholas; Xu, Banghua

    2015-01-01

    This work investigated the effectiveness of a combination of microbubble-ozonation and ultraviolet (UV) irradiation for the treatment of secondary wastewater effluent of a wet-spun acrylic fiber manufacturing plant. Under reactor condition (ozone dosage of 48 mg L-1, UV fluence rate of 90 mW cm-2, initial pH of 8.0, and reaction time of 120 min), the biodegradability (represented as BOD5/CODcr) of the wastewater improved from 0.18 to 0.47. This improvement in biodegradability is related to the degradation of alkanes, aromatic compounds, and other bio-refractory organic compounds. The combination of microbubble-ozonation and UV irradiation synergistically improved treatment efficiencies by 228%, 29%, and 142% for CODcr, UV254 removal and BOD5/CODcr respectively after 120 min reaction time, as compared with the sum efficiency of microbubble-ozonation alone and UV irradiation alone. Hydroxyl radical production in the microbubble-ozonation/UV process was about 1.8 times higher than the sum production in microbubble-ozonation alone and UV irradiation alone. The ozone decomposition rate in the combined process was about 4.1 times higher than that in microbubble-ozonation alone. The microbubble-ozonation/UV process could be a promising technique for the treatment of bio-refractory organics in the acrylic fiber manufacturing industry. © 2015 Royal Society of Chemistry.

  19. Electron attachment to molecules and clusters of atmospheric relevance: oxygen and ozone

    International Nuclear Information System (INIS)

    Matejcik, S.; Cicman, P.; Skalny, J.; Kiendler, A.; Stampfli, P.; Maerk, T.D.; Illenberger, E.; Chu, Y.; Stamatovic, A.

    1996-01-01

    Highly monochromatized electrons are used in a crossed beams experiment to investigate electron attachment to oxygen clusters (O 2 )-n at electron energies from approximately zero eV up to 2 eV. At energies close to zero the attachment cross section for the reaction (O 2 ) n + e → O 2 - varies inversely with the electron energy, indicative of s-wave electron capture to (O 2 ) n . Peaks in the attachment cross section present at higher energies can be ascribed to vibrational levels of the oxygen anion. The vibrational spacings observed can be quantitatively accounted for. In addition electron attachment to ozone and mixed oxygen/ozone clusters has been studied in the energy range up to 4 eV. Absolute attachment cross sections for both fragment ions anions, O - and O 2 - , from ozone could be deduced. Moreover, despite the initially large excess of oxygen molecules in the neutral oxygen/ozone clusters the dominant attachment products are un-dissociated cluster ions (O 3 ) m - including the O 3 - monomer while oxygen cluster ions (O 2 ) n appear with comparatively low intensity. (authors)

  20. Leachate Treatment from Sarimukti Landfill Using Ozone with Sludge from Water Treatment Plant as a Catalyst

    Directory of Open Access Journals (Sweden)

    Yudha Ramdhani Muhammad

    2018-01-01

    Full Text Available Leachate is the liquid waste from anaerobic decomposition in a landfill. The ozonation process can be used for leachate treatment. Sludge from sedimentation in water treatment plant contains 5.96% of Al and 9.35% of Si which can affect of its cation exchange capacity and affects the active site in the catalyst. This study aims to determine the effectivity of sludge in the ozonation process to treat leachate. A 1,5 L semi-batch reactor containing 1 L sample was used in this experiment with the rate of oxygen supply was at 4 L/min taken from ambient air. Two groups of sludge weighing 1.5 grams, 3.0 grams and 4.5 grams were used and activate with physically and chemically activated. The best result was obtained by the physically activated sludge with mass of 4.5 gram O3-L-4,5 AF. The differences of removal efficiency between O3-L-4,5 AF with the control (O3 for turbidity were respectively 13.02% and 7.81%, for EC were 10.57% and 8.29%, for COD were 49.44% and 37.50%, and for residual ozone concentration at the end of contact time were 7.6 mg/L and 9.7 mg/L. It can be concluded that activaed sludge and ozonation can be used as a catalyst in leachate treatment.

  1. Enhanced charge transport and photovoltaic performance of PBDTTT-C-T/PC70BM solar cells via UV-ozone treatment.

    Science.gov (United States)

    Adhikary, Prajwal; Venkatesan, Swaminathan; Adhikari, Nirmal; Maharjan, Purna P; Adebanjo, Olusegun; Chen, Jihua; Qiao, Qiquan

    2013-10-21

    In this work, the electron transport layer of PBDTTT-C-T/PC70BM polymer solar cells were subjected to UV-ozone treatment, leading to improved cell performances from 6.46% to 8.34%. The solar cell efficiency reached a maximum of 8.34% after an optimal 5 minute UV-ozone treatment, and then decreased if treated for a longer time. To the best of our knowledge, the mechanism behind the effects of UV-ozone treatment on the improvement of charge transport and cell performance is not fully understood. We have developed a fundamental understanding of the UV-ozone treatment mechanism, which explains both the enhancements in charge transport and photovoltaic performance at an optimal treatment time, and also the phenomenon whereby further treatment time leads to a drop in cell efficiency. Transient photocurrent measurements indicated that the cell charge transport times were 1370 ns, 770 ns, 832 ns, 867 ns, and 1150 ns for the 0 min, 5 min, 10 min, 15 min, and 20 min UV-ozone treatment times, respectively. Therefore the 5 min UV-ozone treatment time led to the shortest transport time and the most efficient charge transport in the cells. The 5 min UV-ozone treated sample exhibited the highest peak intensity (E2) in the Raman spectra of the treated films, at about 437 cm(-1), indicating that it possessed the best wurtzite phase crystallinity of the ZnO films. Further increasing the UV-ozone treatment time from 5 to 20 min induced the formation of p-type defects (e.g. interstitial oxygen atoms), pushing the ZnO Fermi-level further away from the vacuum level, and decreasing the wurtzite crystallinity.

  2. Influencing factors on microbubble ozonation treatment of acid red 3R wastewater

    Directory of Open Access Journals (Sweden)

    Yurong YA

    2017-08-01

    Full Text Available The microbubble ozonation was used to treat acid red 3R wastewater in order to investigate the influencing factors on its performance. The effects of ozone dose, initial acid red 3R concentration and activated carbon on the performance of microbubble ozonation treatment of acid red 3R wastewater are investigated. The decolorization rate, TOC removal rate, pH variation and ozone utilization efficiency in the microbubble ozonation treatment are compared under different treatment conditions. The results indicate that when increasing ozone dose or decreasing initial acid red 3R concentration, both decolorization rate and TOC removal rate of acid red 3R wastewater increase, but ozone utilization efficiency decreases. The coal-based activated carbon shows strong catalytic activity for microbubble ozonation, which could enhance the decolorization rate and TOC removal rate of acid red 3R wastewater. The better performance of microbubble ozonation treatment is achieved when the ozone dose is 48.3 mg/min and the initial acid red 3R mass concentration is 100 mg/L. Under these conditions, the decolorization efficiency reaches to 100% after treatment for 30 min, the TOC removal efficiency reaches to 78.0% after treatment for 120 min, the reaction rate constant of TOC removal is 0.015 min-1 and the ozone utilization efficiency is higher than 99%. With addition of the coal-based activated carbon of 5 g/L, the decolorization efficiency reaches to 100% after treatment for 15 min, the TOC removal efficiency reaches to 91.2% after treatment for 120 min and the reaction rate constant of TOC removal increases to 0037 min-1.The accumulation and following degradation of intermediate products of small molecule organic acid happens during treatment process, and as a result, the solution pH decreases initially and then increases. Therefore, the optimization of influencing factors for microbubble ozonation could increase both contaminant removal

  3. Effects of ozone treatment on Botrytis cinerea and Sclerotinia sclerotiorum in relation to horticultural product quality.

    Science.gov (United States)

    Sharpe, Deana; Fan, Lihua; McRae, Ken; Walker, Brad; MacKay, Ron; Doucette, Craig

    2009-08-01

    Botrytis cinerea and Sclerotinia sclerotiorum are fungal pathogens that cause the decay of many fruits and vegetables. Ozone may be used as an antimicrobial agent to control the decay. The effect of gaseous ozone on spore viability of B. cinerea and mycelial growth of B. cinerea and S. sclerotiorum were investigated. Spore viability of B. cinerea was reduced by over 99.5% (P < 0.01) and height of the aerial mycelium was reduced from 4.7 mm in the control to less than 1 mm after exposure to 450 or 600 ppb ozone for 48 h at 20 degrees C. Sporulation of B. cinerea was also substantially inhibited by ozone treatments. However, ozone had no significant effect on mycelial growth of S. sclerotiorum in vitro. Decay and quality parameters including color, chlorophyll fluorescence (CF), and ozone injury were further assessed for various horticultural commodities (apple, grape, highbush blueberry, and carrot) treated with 450 ppb of ozone for 48 h at 20 degrees C over a period of 12 d. Lesion size and height of the aerial mycelium were significantly reduced by the ozone treatment on carrots inoculated with mycelial agar plugs of B. cinerea or S. sclerotiorum. Lesion size was also reduced on treated apples inoculated with 5 x 10(6) spores/mL of B. cinerea, and decay incidence of treated grapes was reduced. The 450 ppb ozone for 48 h treatment had no significant effect on color of carrots and apples or on CF of apples and grapes. Ozone, an environmentally sound antimicrobial agent, inactivates microorganisms through oxidization and residual ozone spontaneously decomposes to nontoxic products. It may be applied to fruits and vegetables to reduce decay and extend shelf life.

  4. Percutaneous treatment of lumbar disc herniation by oxygen-ozone injection -clinical study with indication

    International Nuclear Information System (INIS)

    Wang Zhuying; Jiang Caimei; Wang Zhimin

    2006-01-01

    Objective: To study the clinical effect and the range of indications of oxygen-ozone treatment for lumber disc herniation. Methods: 6-15 ml of oxygen-ozone (35-45 μg/ml) were injected percutaneously into lumbar disc. In case of multiple disc herniations, the procedure could be taken with two discs for once. Results: 323 patients with 433 discs were treated by oxygen-ozone injection procedure. Total effective rate was 77.7%. Conclusions: The treatment of lumber disc herniation by oxygen-ozone injection is simple, safe and effective with mild trauma. Oxygen-ozone not only can oxidize the proteoglycan in the nucleus leading to the contraction of nucleus, but also provide anti-inflammation effect with pain relief and without complication yet. (authors)

  5. Kinetics of pulp mill effluent treatment by ozone-based processes

    International Nuclear Information System (INIS)

    Ko, Chun-Han; Hsieh, Po-Hung; Chang, Meng-Wen; Chern, Jia-Ming; Chiang, Shih-Min; Tzeng, Chewn-Jeng

    2009-01-01

    The wastewaters generated from wood pulping and paper production processes are traditionally treated by biological and physicochemical processes. In order to reduce chemical oxygen demand (COD) and color to meet increasingly strict discharge standards, advanced oxidation processes (AOPs) are being adapted as polishing treatment units. Various ozone-based processes were used in this study to treat simulated wastewaters prepared from black liquor from a hardwood Kraft pulp mill in Taiwan. The experimental results showed that the COD and color were primarily removed by direct ozone oxidation and activated carbon adsorption. While the addition of activated carbon could enhance the COD and color removal during ozonation, the addition of hydrogen peroxide improved the color removal only. For the various ozone-based treatment processes, kinetic models were developed to satisfactorily predict the COD and color removal rates. According to the kinetic parameters obtained from the various ozone-based processes, the enhanced COD and color removal of ozonation in the presence of activated carbon was attributed to the regeneration of the activated carbon by ozonation. These kinetic models can be used for reactor design and process design to treat pulping wastewater using ozone-based processes.

  6. Ozone treatment of shell eggs to preserve functional quality and enhance shelf life during storage.

    Science.gov (United States)

    Yüceer, Muhammed; Aday, Mehmet Seçkin; Caner, Cengiz

    2016-06-01

    Eggs have long been recognised as a source of high-quality proteins. Many methods exist to extend shelf life of food and one of them is ozone treatment, which is an emerging technology for disinfecting surfaces in the food industry. This study aimed to extend the shelf life of fresh eggs using gaseous ozone treatments at concentrations of 2, 4 and 6 ppm with exposure times of 2 and 5 min during storage for 6 weeks at 24 °C. The effect of the treatments on interior quality and functional properties of eggs is also reported. Ozone concentration and exposure time significantly affected the Haugh unit (HU), yolk index, albumen pH, relative whipping capacity (RWC), and albumen viscosity of eggs during the storage. Control eggs had the highest albumen pH and lowest albumen viscosity. Attributes such as albumen pH and RWC of eggs exposed to ozone treatments were better than the control samples. The measurement results showed that ozone concentration at 6 ppm and exposure time of 5 min can be applied to fresh eggs and extend shelf life up to 6 weeks at 24 °C storage period. Ozone treatments helped to maintain egg quality for a longer time. Ozone concentrations at 2 and 4 ppm showed promising results in maintaining internal quality and functional properties of fresh eggs during storage. Ozone at high concentration (6 ppm) caused a detrimental effect on eggshell quality. As a result, this study demonstrated that ozone treatments of 2, and especially 4 and 6 ppm concentration maintained eggshell quality during the storage. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

  7. Comparative effects of gamma irradiation and ozone treatment on hygienic quality of Korean red ginseng powder

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Myung-Woo; Yook, Hong-Sun; Kang, Il-Jun; Chung, Cha-Kwon; Kwon, Joong-Ho; Choi, Kang-Ju

    1998-06-01

    For the purpose of improving hygienic quality of Korean red ginseng powder, the comparative effects of gamma irradiation and ozone treatment on the microbial and physicochemical properties were investigated. Gamma irradiation at 7.5 kGy resulted in sterilization of total aerobic bacteria, molds and coliforms below detective levels, while ozone treatment for 8 hours up to 18 ppm did not sufficiently eliminate the microorganisms of the red ginseng powder. Physicochemical properties including compositions of the red ginseng saponin (ginsenosides) and fatty acids, pH and hydrogen donating activity were not significantly changed by gamma irradiation, whereas, ozone treatment caused significant changes in fatty acid compositions, TBA value, pH, acidity and hydrogen donating activity. The results from this study led us to conclude that gamma irradiation was more effective than ozone treatment both for the improvement of hygienic quality and for the maintenance of physicochemical quality of red ginseng powder.

  8. Comparative effects of gamma irradiation and ozone treatment on hygienic quality of Korean red ginseng powder

    International Nuclear Information System (INIS)

    Byun, Myung-Woo; Yook, Hong-Sun; Kang, Il-Jun; Chung, Cha-Kwon; Kwon, Joong-Ho; Choi, Kang-Ju

    1998-01-01

    For the purpose of improving hygienic quality of Korean red ginseng powder, the comparative effects of gamma irradiation and ozone treatment on the microbial and physicochemical properties were investigated. Gamma irradiation at 7.5 kGy resulted in sterilization of total aerobic bacteria, molds and coliforms below detective levels, while ozone treatment for 8 hours up to 18 ppm did not sufficiently eliminate the microorganisms of the red ginseng powder. Physicochemical properties including compositions of the red ginseng saponin (ginsenosides) and fatty acids, pH and hydrogen donating activity were not significantly changed by gamma irradiation, whereas, ozone treatment caused significant changes in fatty acid compositions, TBA value, pH, acidity and hydrogen donating activity. The results from this study led us to conclude that gamma irradiation was more effective than ozone treatment both for the improvement of hygienic quality and for the maintenance of physicochemical quality of red ginseng powder

  9. Electron attachment to oxygen, ozone and other compounds of atmospheric relevance as studied with ultra-high energy resolution

    International Nuclear Information System (INIS)

    Maerk, T.D.; Matejcik, S.; Kiendler, A.; Cicman, P.; Senn, G.; Skalny, J.; Stampfli, P.; Illenberger, E.; Chu, Y.; Stamatovic, A.

    1996-01-01

    The processes of electron attachment to oxygen, ozone, ozone/oxygen cluster and oxygen cluster as well as other compounds of atmospheric relevance (CF 2 Cl 2 , CHCl 3 and CCl 3 Br) were studied with ultra-high energy resolution crossed beam technique

  10. Inactivation of Escherichia coli by ozone treatment of apple juice at different pH levels.

    Science.gov (United States)

    Patil, S; Valdramidis, V P; Cullen, P J; Frias, J; Bourke, P

    2010-09-01

    This research investigated the efficacy of gaseous ozone on the inactivation of Escherichia coli ATCC 25922 and NCTC 12900 strains in apple juice of a range of pH levels, using an ozone bubble column. The pH levels investigated were 3.0, 3.5, 4.0, 4.5 and 5.0. Apple juice inoculated with E. coli strains (10(6)CFU/mL) was treated with ozone gas at a flow rate of 0.12L/min and ozone concentration of 0.048 mg/min/mL for up to 18 min. Results show that inactivation kinetics of E. coli by ozone were affected by pH of the juice. The ozone treatment duration required for achieving a 5-log reduction was faster (4 min) at the lowest pH than at the highest pH (18 min) studied. The relationship between time required to achieve 5log reduction (t(5d)) and pH for both strains was described mathematically by two exponential equations. Ozone treatment appears to be an effective process for reducing bacteria in apple juice and the required applied treatment for producing a safe apple juice is dependant on its acidity level. Copyright 2010 Elsevier Ltd. All rights reserved.

  11. Ozonation and Thermal Pre-Treatment of Municipal Sewage Sludge-Implications for Toxicity and Methane Potential

    DEFF Research Database (Denmark)

    Davidsson, A.; Eriksson, Eva; Fick, J.

    2013-01-01

    The aim of this study was to determine effects on methane potential and overall sludge quality from two different sludge pre-treatment technologies (ozonation high/low dosage and thermal treatment 55/70 degrees C). In general both treatments produced increased methane potential. Thermal treatment...... by ozone treatment and digestion. No statistical significant reduction in concentrations of included pharmaceuticals could be observed....

  12. Landfill leachate treatment with ozone and ozone/hydrogen peroxide systems

    International Nuclear Information System (INIS)

    Tizaoui, Chedly; Bouselmi, Latifa; Mansouri, Loubna; Ghrabi, Ahmed

    2007-01-01

    In the search for an efficient and economical method to treat a leachate generated from a controlled municipal solid waste landfill site (Jebel Chakir) in the region of greater Tunis in Tunisia, ozone alone and ozone combined with hydrogen peroxide were studied. The leachate was characterised by high COD, low biodegradability and intense dark colour. A purpose-built reactor, to avoid foaming, was used for the study. It was found that ozone efficacy was almost doubled when combined with hydrogen peroxide at 2 g/L but higher H 2 O 2 concentrations gave lower performances. Enhancement in the leachate biodegradability from about 0.1 to about 0.7 was achieved by the O 3 /H 2 O 2 system. Insignificant changes in pH that may due to buffering effect of bicarbonate was found. A small decrease in sulphate concentrations were also observed. In contrast, chloride concentration declined at the beginning of the experiment then increased to reach its initial value. Estimates of the operating costs were made for comparison purposes and it was found that the O 3 /H 2 O 2 system at 2 g/L H 2 O 2 gave the lowest cost of about 3.1 TND (∼2.3 USD)/kg COD removed

  13. Combination of ozone and packaging treatments maintained the quality and improved the shelf life of tomato fruit

    Science.gov (United States)

    Zainuri; Jayaputra; Sauqi, A.; Sjah, T.; Desiana, R. Y.

    2018-01-01

    Tomato is very important vegetable crop but has short shelf life. The objective of this research was to determine the effect of ozone and packaging combination treatment on the quality and the storage life of tomato fruit. There were six treatments including: control (without ozone and packaging); without ozone and packaged with polyethylene bag; without ozone and polyethylene terephtalate punnet; with ozone but without packaging; with ozone and packaged with polyethylene bag; and with ozone and polyethylene terephtalate punnet. Each treatment was made into 3 replications. Tomato samples were harvested at turning stage. Ozone treatment was applied for 60 seconds. Tomatoes were then treated with and without packaging. The fruit were then stored at room temperature for up to 12 days. The parameters for assessment were water content, color, texture, weight loss and the population of naturally contamination Escherichia coli. Each parameter was assessed on day 0, 6 and 12 of storage. The results indicated that combination of ozone and packaging treatments significantly affected the physical and biochemical changes (water content, color, texture and weight loss) of the fruit, suppressed the microbiological contamination on the fruit and maintained fruit freshness or quality after 12 days of storage. The combination of ozone and perforated polyethylene packaging treatment was the best treatment to maintain the quality and prolonged the shelf life of tomato fruit to be 12 days at room temperature.

  14. Ozonated water in the post-harvest treatment of coffee fruits

    Directory of Open Access Journals (Sweden)

    Fernando J. B. Brandão

    Full Text Available ABSTRACT Ozone is used in many countries for the treatment of effluents, becoming a viable alternative in sanitation of coffee wastewater. However, the strong ozone oxidation, responsible for its germicidal effect, can also compromise grain and beverage quality. The objective of this study was to evaluate the quality of Arabica coffee in different periods of treatment with ozonated water and its effect after drying. Coffee fruits were subjected to ozonation at regular intervals of 0, 5, 10, 20, and 30 min, with continuous stirring promoted by a recirculating water system at constant rate of 1 ppm of solubilized ozone. The design was completely randomized with five treatments and four replicates. After obtaining the data, the analysis of variance was performed and means were compared by Tukey test (p ≤ 0.05. The results showed a partial reduction of fungi after washing with ozonated water, but the same effect was not observed after drying. For coffee quality analysis, the longest times of exposure to the solubilized gas in the water produced some negative results in electrical conductivity and total and reducing sugars. However, the sensory quality of the beverage was maintained.

  15. [Assessment of antibacterial efficacy of ozone therapy in treatment of caries at the white spot stage].

    Science.gov (United States)

    Makeeva, I M; Turkina, A Yu; Margaryan, E G; Paramonov, Yu O; Polyakova, M A

    Effect on cariogenic flora is the key toremineralizing therapy efficacy in treatment of initial caries (at the white spot stage). Ozone in dentistry is used as a highly effective antibacterial agent. Treatment of white spot lesions with the ozone-air mixture leads to significant increase of efficacy in non-invasive treatment of initial caries. clinical and microbiological assessment of antibacterial efficacy of ozone therapy in treatment of caries at the white spot stage. The trial recruited 86 patients for non-invasive treatment of caries at the white spot stage which included the complex of professional oral hygiene, medicamental treatment of white spot lesions with hydrogen peroxide 3% and chlorhexidinedigluconate 0,2%, treatment with the ozone-air mixture and application of hydroxyapatite Са2+. Material for microbiological study was received before the treatment, after the complex of professional oral hygiene and medicamental treatment of white spot lesions conducted as well as after the treatment with the ozone-air mixture. Before the treatment up to 16 kinds of microorganisms on the surface of white spot lesion were detected with the following shares: S. mutans (19.9%), S. salivarius (15.1%), S. epidermidis (8.7%), S. mitis (6.5%), Lactobacillus (6.5%) and different kinds of staphylococci (10.8%). After the complex of professional oral hygiene and medicamental treatment conducted decrease in number of cariogenic microorganisms was indicated as follows: S. mutans - from 1·105 to 1·104, S. salivarius - from 1·107 to 1·106, S. epidermidis - from 1·105 to 1·104, S. mitis - from 1·104 to 1·103, Lactobacillus - from 1·104 tо 1·103. After the treatment of tooth enamel with the ozone-air mixture increase in microorganisms was not observed. The efficacy of ozone on cariogenic microorganisms exceeds significantly the efficacy of 3% hydrogen peroxide and 0,2% chlorhexidinedigluconate. It is strongly advisable to include ozone in protocol of non

  16. Purification of ammonia-containing trap waters from atomic power plant by ozone treatment

    International Nuclear Information System (INIS)

    Grachok, M.A.; Prokudina, S.A.; Shulyat'ev, M.I.

    1990-01-01

    The aim of research was to study the process of ozonation of ammonia-containing trap waters from the Kursk Atomic Power Plant both on the model solutions and on real ones. Different factors (pH of the medium, temperature, concentration of the initial substances) have been studied for their effect on ozonation of aqueous ammonia solutions, model solutions of trap waters from the Kursk Atomic Power Plant as well as ammonia-containing trap waters and liquid radioactive wastes delivered to special water treatment at the Kursk Atomic Power Plant. It is shown that in all the cases the highest rate of ammonia oxidation by ozone is observed in the alkaline medium (pH 1.4-11.0) and at 55 deg C. The obtained results have shown that a method of ozonation followed by evaporation of water to be purified can be used to treat ammonia-containing waters from atomic power plant

  17. TREATMENT OF LANDFILL LEACHATE BY COUPLING COAGULATION-FLOCCULATION OR OZONATION TO GRANULAR ACTIVATED CARBON ADSORPTION.

    Science.gov (United States)

    Oloibiri, Violet; Ufomba, Innocent; Chys, Michael; Audenaert, Wim; Demeestere, Kristof; Van Hulle, Stijn W H

    2015-01-01

    A major concern for landfilling facilities is the treatment of their leachate. To optimize organic matter removal from this leachate, the combination of two or more techniques is preferred in order to meet stringent effluent standards. In our study, coagulation-flocculation and ozonation are compared as pre- treatment steps for stabilized landfill leachate prior to granular activated carbon (GAC) adsorption. The efficiency of the pre treatment techniques is evaluated using COD and UVA254 measurements. For coagulation- flocculation, different chemicals are compared and optimal dosages are determined. After this, iron (III) chloride is selected for subsequent adsorption studies due to its high percentage of COD and UVA254 removal and good sludge settle-ability. Our finding show that ozonation as a single treatment is effective in reducing COD in landfill leachate by 66% compared to coagulation flocculation (33%). Meanwhile, coagulation performs better in UVA254 reduction than ozonation. Subsequent GAC adsorption of ozonated effluent, coagulated effluent and untreated leachate resulted in 77%, 53% and 8% total COD removal respectively (after 6 bed volumes). The effect of the pre-treatment techniques on GAC adsorption properties is evaluated experimentally and mathematically using Thomas and Yoon-Nelson models. Mathematical modelling of the experimental GAC adsorption data shows that ozonation increases the adsorption capacity and break through time with a factor of 2.5 compared to coagulation-flocculation.

  18. Morphological and Metabolic Parameters of Red Blood Cells after Their Treatment with Ozone

    Directory of Open Access Journals (Sweden)

    Anna V. Deryugina

    2018-01-01

    Full Text Available The purpose of the study was to assess the morphology of red blood cells (RBC and the association of morphological parameters with lipid peroxidation processes and the content of organic phosphates in RBC when treating packed red blood cells with the ozonized saline solution (with an ozone concentration of 2 mg/l after different storage periods.Materials and methods. The morphology of human RBC, the concentration of malonic dialdehyde (MDA in RBC, the catalase activity, the concentration of ATP and 2,3-diphosphoglycerate (2,3-DPG were studied before and after treatment of RBC with the ozonized saline (with the ozone concentration of 2 mg/l after 7, 14, 21 and 30 days of storage.Results. The effect of ozone (2 ng/l in vitro on the packed red blood cells after 7–21 days of storage contributed to the recovery of RBC shape, increased the concentration of ATP and 2,3-DPG, and optimized the lipid peroxidation. Ozone did not demonstrate a pronounced positive effect on these parameters when the packed RBCs were stored for 30 days.Conclusion. The treatment of the packed RBCs with the ozonized saline solution (with the ozone concentration of 2 mg/l contributed to the recovery of the discocyte count due to optimization of lipid peroxidation processes in cell membranes and enhanced the synthesis of organic phosphates in cells due to the activation of glycolysis and the pentose phosphate pathway. This can be used to improve the morphological and metabolic status of the packed RBCs before their transfusion. 

  19. Synthesis of Co3O4 nanosheets via electrodeposition followed by ozone treatment and their application to high-performance supercapacitors

    Science.gov (United States)

    Kung, Chung-Wei; Chen, Hsin-Wei; Lin, Chia-Yu; Vittal, R.; Ho, Kuo-Chuan

    2012-09-01

    A thin film of Co3O4 nanosheets is electrodeposited on a flexible Ti substrate by a one-step potentiostatic method, followed by an UV-ozone treatment for 30 min. The films before and after the UV-ozone treatment are characterized with X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The film is composed of Co(OH)2 before UV-ozone treatment, and of Co3O4 after the treatment. The morphologies of both films are examined by scanning electron microscopy (SEM) and transmission electron microscope (TEM). The obtained films are composed of nanosheets, and there is no change in their sheet-like morphology before and after the UV-ozone treatment. When applied for a supercapacitor, the Co3O4 modified Ti electrode (Co3O4/Ti) shows a far higher capacitance than that of the Co(OH)2 modified Ti electrode. The electrodeposition time and NaOH concentration in the electrolyte are optimized. A remarkably high specific capacitance of 1033.3 F g-1 is obtained for the Co3O4 thin film at a charge-discharge current density of 2.5 A g-1. The long-term stability data shows that there is still 77% of specific capacitance remaining after 3000 repeated charge-discharge cycles. The high specific capacitance and long-term stability suggest the potential use of Co3O4/Ti for making a flexible supercapacitor.

  20. Effect of ozone on leaf cell membranes

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, E S; Thomson, W W; Mudd, J B

    1973-01-01

    The objective of this study was to determine the effects of ozone on membrane lipids and on the electron-density patterns of cell membranes in electron micrographs. Analysis of fatty acids from tobacco leaves fumigated with ozone indicated that there was no significant difference between the ozone-treated and the control plants in the relative amounts of the fatty acids. This suggests that if the primary site of ozone action is unsaturated lipids in membranes then the amounts of affected unsaturated fatty acids are too small to be detected by gas chromatography. In support of this, characteristic electron-microscopic images of membranes are observed in cells of fumigated leaves. However, measurements of the length and width of the chloroplasts and the determination of axial ratios indicated that the ozone treatment resulted in a shrinkage of the chloroplasts. In contrast, mitochondrial changes are apparently explained in terms of ozone-induced swelling. 33 references, 3 figures, 1 table.

  1. Optimization of stabilized leachate treatment using ozone/persulfate in the advanced oxidation process

    International Nuclear Information System (INIS)

    Abu Amr, Salem S.; Aziz, Hamidi Abdul; Adlan, Mohd Nordin

    2013-01-01

    Highlights: ► Ozone and persulfate reagent (O 3 /S 2 O 8 2- ) was used to treat stabilized leachate. ► Central composite design (CCD) with response surface methodology (RSM) was applied. ► Operating variables including ozone and persulfate dosage, pH variance, and reaction time. ► Optimum removal of COD, color, and NH 3 –N was 72%, 96%, and 76%, respectively. ► A good value of ozone consumption (OC) obtained with 0.60 (kg O 3 /kg COD). - Abstract: The objective of this study was to investigate the performance of employing persulfate reagent in the advanced oxidation of ozone to treat stabilized landfill leachate in an ozone reactor. A central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the relationships between operating variables, such as ozone and persulfate dosages, pH, and reaction time, to identify the optimum operating conditions. Quadratic models for the following four responses proved to be significant with very low probabilities ( 3 –N, and ozone consumption (OC). The obtained optimum conditions included a reaction time of 210 min, 30 g/m 3 ozone, 1 g/1 g COD 0 /S 2 O 8 2- ratio, and pH 10. The experimental results were corresponded well with predicted models (COD, color, and NH 3 –N removal rates of 72%, 96%, and 76%, respectively, and 0.60 (kg O 3 /kg COD OC). The results obtained in the stabilized leachate treatment were compared with those from other treatment processes, such as ozone only and persulfate S 2 O 8 2- only, to evaluate its effectiveness. The combined method (i.e., O 3 /S 2 O 8 2- ) achieved higher removal efficiencies for COD, color, and NH 3 –N compared with other studied applications. Furthermore, the new method is more efficient than ozone/Fenton in advanced oxidation process in the treatment of the same studied leachate

  2. Effect of UV/ozone treatment on the nanoscale surface properties of gold implanted polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Kisić, Danilo; Nenadović, Miloš [INS Vinca, Laboratory of Atomic Physics, University of Belgrade, Mike Alasa 12-14, 11001 Belgrade (Serbia); Štrbac, Svetlana [ICTM Institute of Electrochemistry, University of Belgrade, Njegoseva 12, 11001 Belgrade (Serbia); Adnadjević, Borivoj [Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, 11158 Belgrade (Serbia); Rakočević, Zlatko, E-mail: zlatkora@vinca.rs [INS Vinca, Laboratory of Atomic Physics, University of Belgrade, Mike Alasa 12-14, 11001 Belgrade (Serbia)

    2014-07-01

    The effect of ultraviolet (UV) ozone treatment on the surface properties of gold implanted high density polyethylene (HDPE) was investigated at a nanoscale using Atomic Force Microscopy (AFM). HDPE samples were modified by the implantation of gold ions at a dose of 5 × 10{sup 15} ions/cm{sup 2}, using energies of 50, 100, 150, and 200 keV, and subsequently treated with UV/ozone. AFM surface topography images revealed that after UV/ozone treatment, the surface roughness of all Au/HDPE samples increased, while Power Spectral Density function increased only for samples implanted using higher energies, with a maximum for 150 keV. The chemical surface composition was homogenous in all cases, which was evidenced by the appearance of single peaks in the histograms obtained from the phase AFM images. For UV/ozone treated samples, the shift of the peaks positions in the histograms to the higher values of the phase lag with respect to untreated ones indicated the decrease of surface hardness. Besides, a significant change of fractal dimension of surface grains is observed after UV/ozone treatment.

  3. MBBR evaluation for oil refinery wastewater treatment, with post-ozonation and BAC, for wastewater reuse.

    Science.gov (United States)

    Schneider, E E; Cerqueira, A C F P; Dezotti, M

    2011-01-01

    This work evaluated the performance of a Moving Bed Biofilm Reactor (MBBR) in the treatment of an oil refinery wastewater. Also, it investigated the possibility of reuse of the MBBR effluent, after ozonation in series with a biological activated carbon (BAC) column. The best performance of the MBBR was achieved with a hydraulic retention time (HRT) of 6 hours, employing a bed to bioreactor volume ratio (V(B)/V(R)) of 0.6. COD and N-NH₄(+) MBBR effluent concentrations ranged from 40 to 75 mg L⁻¹ (removal efficiency of 69-89%) and 2 to 6 mg L⁻¹ (removal efficiency of 45-86%), respectively. Ozonation carried out for 15 min with an ozone concentration of 5 mg L⁻¹ was able to improve the treated wastewater biodegradability. The treatment performance of the BAC columns was practically the same for ozonated and non ozonated MBBR effluents. The dissolved organic carbon (DOC) content of the columns of the activated carbon columns (CAG) was in the range of 2.1-3.8 mg L⁻¹, and the corresponding DOC removal efficiencies were comprised between 52 and 75%. The effluent obtained at the end of the proposed treatment presented a quality, which meet the requirements for water reuse in the oil refinery.

  4. Novel Water Treatment Processes Based on Hybrid Membrane-Ozonation Systems: A Novel Ceramic Membrane Contactor for Bubbleless Ozonation of Emerging Micropollutants

    Directory of Open Access Journals (Sweden)

    Stylianos K. Stylianou

    2015-01-01

    Full Text Available The aim of this study is the presentation of novel water treatment systems based on ozonation combined with ceramic membranes for the treatment of refractory organic compounds found in natural water sources such as groundwater. This includes, firstly, a short review of possible membrane based hybrid processes for water treatment from various sources. Several practical and theoretical aspects for the application of hybrid membrane-ozonation systems are discussed, along with theoretical background regarding the transformation of target organic pollutants by ozone. Next, a novel ceramic membrane contactor, bringing into contact the gas phase (ozone and water phase without the creation of bubbles (bubbleless ozonation, is presented. Experimental data showing the membrane contactor efficiency for oxidation of atrazine, endosulfan, and methyl tert-butyl ether (MTBE are shown and discussed. Almost complete endosulfan degradation was achieved with the use of the ceramic contactor, whereas atrazine degradation higher than 50% could not be achieved even after 60 min of reaction time. Single ozonation of water containing MTBE could not result in a significant MTBE degradation. MTBE mineralization by O3/H2O2 combination increased at higher pH values and O3/H2O2 molar ratio of 0.2 reaching a maximum of around 65%.

  5. Destruction of disinfection byproducts and their precursors in swimming pool water by combined UV treatment and ozonation

    DEFF Research Database (Denmark)

    Cheema, Waqas Akram; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    Both UV treatment and ozonation are used to reduce different types of disinfection byproducts (DBP) in swimming pools. UV treatment is most common as it is particularly efficient in removing the repulsive chlorine like smelling chloramines (combined chlorine). UV treatment of a pool water increased...... chlorine reactivity and formation of chlor-organic DBP such as trihalomethanes. Based on the similar selective reactivity of ozone and chlorine we hypothesized that the created reactivity towards chlorine by UV treatment of dissolved organic matter in pool water might also be expressed as an increased...... reactivity towards ozone and that ozonation might saturate the chlorine reactivity created by UV treatment and mitigate the increased DBP formation. By experimentally treating pool water samples, we found that UV treatment makes pool water highly reactive to ozone. The created reactivity towards chlorine...

  6. Life Cycle Assessment of urban wastewater reuse with ozonation as tertiary treatment

    International Nuclear Information System (INIS)

    Munoz, Ivan; Rodriguez, Antonio; Rosal, Roberto; Fernandez-Alba, Amadeo R.

    2009-01-01

    Life Cycle Assessment has been used to compare different scenarios involving wastewater reuse, with special focus on toxicity-related impact categories. The study is based on bench-scale experiments applying ozone and ozone in combination with hydrogen peroxide to a wastewater effluent from a Spanish sewage treatment plant. Two alternative characterisation models have been used to account for toxicity of chemical substances, namely USES-LCA and EDIP97. Four alternative scenarios have been assessed: wastewater discharge plus desalination supply, wastewater reuse without tertiary treatment, wastewater reuse after applying a tertiary treatment consisting on ozonation, and wastewater reuse after applying ozonation in combination with hydrogen peroxide. The results highlight the importance of including wastewater pollutants in LCA of wastewater systems assessing toxicity, since the contribution of wastewater pollutants to the overall toxicity scores in this case study can be above 90%. Key pollutants here are not only heavy metals and other priority pollutants, but also non-regulated pollutants such as pharmaceuticals and personal care products. Wastewater reuse after applying any of the tertiary treatments considered appears as the best choice from an ecotoxicity perspective. As for human toxicity, differences between scenarios are smaller, and taking into account the experimental and modelling uncertainty, the benefits of tertiary treatment are not so clear. From a global warming potential perspective, tertiary treatments involve a potential 85% reduction of greenhouse gas emissions when compared with desalination

  7. Fumigation characteristics of ozone in postharvest treatment of Kabkab dates (Phoenix dactylifera L.) against selected insect infestation.

    Science.gov (United States)

    Niakousari, Mehrdad; Erjaee, Zahra; Javadian, Shahram

    2010-04-01

    Methyl bromide fumigation, the most accepted quarantine treatment for dates and many other dried commodities, will be phased out by 2015 worldwide. As a result, there is a critical need to develop durable alternatives for methyl bromide as postharvest treatments of agricultural commodities. This article presents a new method for postharvest treatment of Kabkab dates (Phoenix dactylifera L.) by application of gaseous ozone to reduce or eliminate all life stages (adults, larvae, and eggs) of Indian meal moth (Plodia interpunctella) and sawtooth grain beetle (Oryzaephilus surinamensis). The effect of the ozonation process on the sugar content of dates was also evaluated. Infested dates were exposed to ozone concentrations of 600, 1,200, 2,000, and 4,000 ppm for 1 and 2 h. As insect eggs are known to be most tolerant to many chemical or physical treatments, they were additionally exposed to an atmosphere of pure carbon dioxide prior to ozonation. Exposing samples to ozone concentrations of >2,000 ppm for 2 h resulted in complete mortality of larvae and adults. Exposure to 4,000 ppm of ozone for 2 h resulted in 80% mortality of eggs, and exposure to CO(2) prior to ozonation did not improve the effect of ozonation on eggs. Ozone did not have any influence on the sugar content of Kabkab dates.

  8. Solid waste electron beam treatment

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    1998-01-01

    The possible applications of electron accelerators for solid waste treatment are discussed in the report. The elaborated technologies allow to recycle of materials (e.g. cellulosic materials in municipal waste), improve their hygienic standards (agricultural usage of sludge from municipal waste water treatment) and reduce harmful to environment chemical usage (cellulose degradation). These are environment friendly advanced technologies which meets demands waste recycling. (author)

  9. Solid waste electron beam treatment

    Energy Technology Data Exchange (ETDEWEB)

    Chmielewski, A G

    1998-07-01

    The possible applications of electron accelerators for solid waste treatment are discussed in the report. The elaborated technologies allow to recycle of materials (e.g., cellulosic materials in municipal waste), improve their hygienic standards (agricultural usage of sludge from municipal waste water treatment) and reduce harmful to environment chemical usage (cellulose degradation). These are environment friendly advanced technologies which meets demands waste recycling. (author)

  10. NOx reduction by ozone injection and direct plasma treatment

    DEFF Research Database (Denmark)

    Stamate, Eugen; Salewski, Mirko

    2012-01-01

    NOx reduction by ozone injection and direct plasma treatment is investigated for different process parameters in a 6 m long serpentine reactor. Several aspects including the role of mixing scheme, water vapours, steep temperature gradient and time dependet NOx levels are taken into consideration...

  11. Description of the surface water filtration and ozone treatment system at the Northeast Fishery Center

    Science.gov (United States)

    A water filtration and ozone disinfection system was installed at the U.S. Fish and Wildlife Service's Northeast Fishery Center in Lamar, Pennsylvania to treat a surface water supply that is used to culture sensitive and endangered fish. The treatment system first passes the surface water through dr...

  12. Transformation products and reaction kinetics of fragrances in advanced wastewater treatment with ozone

    DEFF Research Database (Denmark)

    Janzen, Niklas; Dopp, Elke; Hesse, Julia

    2011-01-01

    ) ethanone (musk ketone/MK), and 1-(2,3,8,8-tetramethyl-1,3,4,5,6,7-hexahydronaphthalen-2-yl)ethanone (OTNE) with ozone in tap water as well as waste water treatment plant (WWTP) effluents is described. Several transformation products are characterized by means of gas chromatography coupled to mass...

  13. Treatment of Egyptian Maghara coal by plasma ozone synthesized by silent discharge

    CERN Document Server

    Salem, M A; Garamoon, A A; Hassouba, M A

    2003-01-01

    A sample of pyrite rich bituminous coal collected from the main coal seam of Maghara mine, northern sinai, was treated by ozone plasma. The latter was synthesized using silent discharge method (10 kv a.c. and 50 hz). The room temperature Moessbauer spectra of untreated coal sample was easily fitted to two doublet, whose parameters matched those of pyrite (FeS sub 2) and sulfate (FeSO sub 4.H sub 2 O) in addition to hematite. After treatment by ozone plasma, a doublet ascribed to pyrite was observed. The extent of pyrite oxidation to jarosite (Fe sub 2 (SO sub 4) sub 3. nH sub 2 O) was monitored by their relative spectral areas, the incomplete oxidation of pyrite may be attributed to the presence of calcium sulfate layer which acts a screen of ozone.

  14. Non-target screening to trace ozonation transformation products in a wastewater treatment train including different post-treatments.

    Science.gov (United States)

    Schollée, Jennifer E; Bourgin, Marc; von Gunten, Urs; McArdell, Christa S; Hollender, Juliane

    2018-05-25

    Ozonation and subsequent post-treatments are increasingly implemented in wastewater treatment plants (WWTPs) for enhanced micropollutant abatement. While this technology is effective, micropollutant oxidation leads to the formation of ozonation transformation products (OTPs). Target and suspect screening provide information about known parent compounds and known OTPs, but for a more comprehensive picture, non-target screening is needed. Here, sampling was conducted at a full-scale WWTP to investigate OTP formation at four ozone doses (2, 3, 4, and 5 mg/L, ranging from 0.3 to 1.0 gO 3 /gDOC) and subsequent changes during five post-treatment steps (i.e., sand filter, fixed bed bioreactor, moving bed bioreactor, and two granular activated carbon (GAC) filters, relatively fresh and pre-loaded). Samples were measured with online solid-phase extraction coupled to liquid chromatography high-resolution tandem mass spectrometry (LC-HRMS/MS) using electrospray ionization (ESI) in positive and negative modes. Existing non-target screening workflows were adapted to (1) examine the formation of potential OTPs at four ozone doses and (2) compare the removal of OTPs among five post-treatments. In (1), data processing included principal component analysis (PCA) and chemical knowledge on possible oxidation reactions to prioritize non-target features likely to be OTPs. Between 394 and 1328 unique potential OTPs were detected in positive ESI for the four ozone doses tested; between 12 and 324 unique potential OTPs were detected in negative ESI. At a specific ozone dose of 0.5 gO 3 /gDOC, 27 parent compounds were identified and were related to 69 non-target features selected as potential OTPs. Two OTPs were confirmed with reference standards (venlafaxine N-oxide and chlorothiazide); 34 other potential OTPs were in agreement with literature data and/or reaction mechanisms. In (2), hierarchical cluster analysis (HCA) was applied on profiles detected in positive ESI mode across the

  15. Treatment of high strength distillery wastewater (cherry stillage) by integrated aerobic biological oxidation and ozonation.

    Science.gov (United States)

    Beltrán, F J; Alvarez, P M; Rodríguez, E M; García-Araya, J F; Rivas, J

    2001-01-01

    The performance of integrated aerobic digestion and ozonation for the treatment of high strength distillery wastewater (i.e., cherry stillage) is reported. Experiments were conducted in laboratory batch systems operating in draw and fill mode. For the biological step, activated sludge from a municipal wastewater treatment facility was used as inoculum, showing a high degree of activity to distillery wastewater. Thus, BOD and COD overall conversions of 95% and 82% were achieved, respectively. However, polyphenol content and absorbance at 254 nm (A(254)) could not be reduced more than 35% and 15%, respectively, by means of single biological oxidation. By considering COD as substrate, the aerobic digestion process followed a Contois' model kinetics, from which the maximum specific growth rate of microorganisms (mu(max)) and the inhibition factor, beta, were then evaluated at different conditions of temperature and pH. In the combined process, the effect of a post-ozonation stage was studied. The main goals achieved by the ozonation step were the removal of polyphenols and A(254). Therefore, ozonation was shown to be an appropriate technology to aid aerobic biological oxidation in the treatment of cherry stillage.

  16. Electron beam gaseous pollutants treatment

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    1999-01-01

    Emission of gaseous pollutants, mostly during combustion of fossil fuels, creates a threat to the environment. New, economical technologies are needed for flue gas treatment. A physico-chemical basis of the process using electron beam for the simultaneous removal of sulfur and nitrogen oxides and volatile organic compounds are presented in this report. Development of the process and its upscaling has been discussed. (author)

  17. Enhanced biodegradation of petrochemical wastewater using ozonation and BAC advanced treatment system

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chi-Kang; Tsai, Tsung-Yueh; Liu, Jiunn-Ching; Chen, Mei-Chen [Energy and Resources Labs., ITRI, Hsinchu (Taiwan)

    2001-07-01

    The characteristics of degradation/conversion of bio-refractory and the growth of a biofilm are investigated in laboratory-scale pre-ozonation and lifted moving-bed biological activated carbon (BAC) advanced treatment processes treating phenol, benzoic acid, aminobenzoic acid and petrochemical industry wastewater which contains acrylonitrile butadiene styrene (ABS). The optimal reaction time and ozone dosage of pre-ozonation for bio-refractory conversion were determined to be 30 min and 100-200mg O{sub 3}/hr, respectively. After pre-ozonation of 30 min treatment, BOD{sub 5}/COD ratio of influent and effluent increased apparently from 20 to 35%, approximately. However, the change of pH in pre-ozonation was inconspicuous. The optimal flow rate of influent and air were controlled at 1.6 1/h and 120-l50nl/min in lifted moving-bed BAC advanced treatment reactor. A COD removal efficiency of 85-95% and 70-90% may be maintained by using an organic loading of 3.2-6.3kg COD/m{sup 3} day and 0.6-1.6 kg-COD/m{sup 3} day with an HRT of 6.0 h as secondary and advanced treatment system, respectively. The time required for the BAC bed to be regenerated by a thermal regeneration is prolonged 4-5 times more than that of GAC system. It can be estimated that the enhanced COD removal capability of the biofilm was not only due to the increase in the COD removal capability of acclimated bacteria, but also due to species succession of bacteria in bio-film ecosystem. (Author)

  18. Clinical observation on thoracic paravertebral nerve block with ozone treatment in patients with postherpetic neuralgia

    Directory of Open Access Journals (Sweden)

    GUO Xiang-fei

    2013-10-01

    Full Text Available Objective To analyze the clinical efficacy of thoracic paravertebral nerve block with ozone in the treatment of postherpetic neuralgia. Methods Eighty-five patients suffered postherpetic neuralgia were divided into 4 groups: Group A (oral drugs + intramuscular injection of vitamin B12 + local nerve block of lesion area, Group B (oral drugs + intramuscular injection of compound trivitamin B + local nerve block of lesion area, Group C (oral drugs + intramuscular injection of compound trivitamin B + thoracic paravertebral nerve block + local nerve block of lesion area, Group D (oral drugs + intramuscular injection of compound trivitamin B + thoracic paravertebral nerve block with ozone + local nerve block of lesion area. Treatment outcomes were evaluated by Visual Analogue Scale (VAS, Quality of Sleep (QS, Self-Rating Depression Scale (SDS and C-reactive protein (CRP before treatment and 4 weeks after treatment. Results After treatment, VAS, QS and SDS scores of 4 groups were lower than that before treatment, and the differences were statistically significant (P 0.05, for all, while a significant change in CRP was observed in patients of group D between before and after treatment (P < 0.05. The improvement of VAS, QS and SDS scores of group D was significantly better than other 3 groups (P < 0.05, for all. Conclusion Thoracic paravertebral nerve block combined with ozone is a quick and effective method for postherpetic neuralgia patients.

  19. Treatment rate improvement of the ozone oxidation method for laundry waste water

    International Nuclear Information System (INIS)

    Matsuo, Toshiaki; Nishi, Takashi

    2001-01-01

    Radioactive laundry waste water generated in nuclear power plants includes organic compounds to be removed, for which ozone oxidation treatment is a possibility. To verify the applicability, its total organic carbon concentration (TOC) lowering rate improvement was examined in 0.5x10 -3 m 3 batch and 3x10 -2 m 3 pilot equipment experiments. In the batch experiments, ozone at a concentration of 200 g/Nm 3 was dispersed into 0.5x10 -3 m 3 of Simulated Laundry Waste Water (SLWW) with TOC of 11 mM. Total organic carbon concentration was measured every hour to see the effects of the temperature, and the initial concentrations of both H 2 O 2 and NaOH which were added to urge OH radical generation from ozone. In the pilot equipment experiments, 1x10 -2 to 3x10 -2 m 3 of the SLWW were circulated using an ejector to disperse the ozone. The influences of the flow rate and the SLWW volume on lowering TOC were examined, because they were related to the ejector dispersion performance and the appropriate ozone addition per SLWW volume. Appropriate initial H 2 O 2 and NaOH concentrations in the batch experiments were 14.7 mM and 1 mM, respectively. Lowering of TOC became faster at higher temperatures, because ozone self-decomposition and OH radial diffusion to the organic compound molecules were promoted. Lowering of TOC also became faster at higher flow rates, while the influence of the volume became saturated. (author)

  20. Ozone and membrane filtration based strategies for the treatment of cork processing wastewaters

    Energy Technology Data Exchange (ETDEWEB)

    Benitez, F. Javier [Departamento de Ingenieria Quimica, Universidad de Extremadura, 06071 Badajoz (Spain)], E-mail: javben@unex.es; Acero, Juan L.; Leal, Ana I.; Real, Francisco J. [Departamento de Ingenieria Quimica, Universidad de Extremadura, 06071 Badajoz (Spain)

    2008-03-21

    The degradation of the pollutant organic matter present in the cork processing wastewater was studied by combining chemical treatments, which used ozone and some Advanced Oxidation Processes, and membrane filtration procedures. Two schemes were conducted: firstly, a single ozonation stage followed by an UF stage; and secondly, a membrane filtration stage, using different MF and UF membranes, followed by a chemical oxidation stage, where ozone, UV radiation, and the AOPs constituted by ozone plus UV radiation and ozone plus hydrogen peroxide, were used. The membrane filtration stages were carried out in tangential filtration laboratory equipment, and the membranes used were two MF membranes with pores sizes of 0.65 and 0.1 {mu}m, and three UF membranes with molecular weights cut-off of 300, 10, and 5 kDa. The effectiveness of the different stages (conversions in the chemical procedures and rejection coefficients in the membrane processes) were evaluated in terms of several parameters which measure the global pollutant content of the wastewater: COD, absorbance at 254 nm, tannins content, color, and ellagic acid. In the ozonation/UF combined process the following removals were achieved: 100% for ellagic acid and color, 90% for absorbance at 254 nm, more than 80% for tannins, and 42-57% for COD reduction. In the filtration/chemical oxidation combined process, 100% elimination of ellagic acid, more than 90% elimination in color, absorbance at 254 nm and tannins, and removal higher than 80% in COD were reached, which indicates a greater purification power of this combination.

  1. The economic pre-treatment of coal mine drainage water with caustic and ozone.

    Science.gov (United States)

    Boyden, B H; Nador, L; Addleman, S; Jeston, L

    2017-09-01

    Coal mine drainage waters are low in pH with varying amounts of iron and manganese and are generally brackish. The Austar Coal Mine in NSW, Australia, sought alternatives to their current lime dosing as the pre-treatment before the downstream reverse osmosis plant. Undesirable operating aspects of the current system include manganese and gypsum scaling/fouling, the need for anti-scalants and reduced water recovery. Thirteen processes for acid mine drainage were initially considered. The preferred process of caustic and ozone for Mn(II) oxidation was pilot tested at up to 0.74 kL/hr at the mine site. Under proper conditions and no aeration, about 81 per cent of the Fe could be removed (initially at 156 mg/L) as green rust. Supplemental aeration followed first-order kinetics and allowed 99.9 per cent Fe(II) oxidation and removal but only with a hydraulic residence time of about 47 minutes. The addition of supplemental Cu catalyst improved Fe removal. Ozone applied after caustic was effective in stoichiometrically oxidising recalcitrant Mn(II) and any remaining Fe(II). Control of the ozonation was achieved using the oxidation reduction potential during oxidation of the Mn(II) species. The use of caustic, followed by ozone, proved economically comparable to the current lime pre-treatment.

  2. Dissolved organic nitrogen and its biodegradable portion in a water treatment plant with ozone oxidation.

    Science.gov (United States)

    Wadhawan, Tanush; Simsek, Halis; Kasi, Murthy; Knutson, Kristofer; Prüβ, Birgit; McEvoy, John; Khan, Eakalak

    2014-05-01

    Biodegradability of dissolved organic nitrogen (DON) has been studied in wastewater, freshwater and marine water but not in drinking water. Presence of biodegradable DON (BDON) in water prior to and after chlorination may promote formation of nitrogenous disinfectant by-products and growth of microorganisms in the distribution system. In this study, an existing bioassay to determine BDON in wastewater was adapted and optimized, and its application was tested on samples from four treatment stages of a water treatment plant including ozonation and biologically active filtration. The optimized bioassay was able to detect BDON in 50 μg L(-1) as N of glycine and glutamic solutions. BDON in raw (144-275 μg L(-1) as N), softened (59-226 μg L(-1) as N), ozonated (190-254 μg L(-1) as N), and biologically filtered (17-103 μg L(-1) as N) water samples varied over a sampling period of 2 years. The plant on average removed 30% of DON and 68% of BDON. Ozonation played a major role in increasing the amount of BDON (31%) and biologically active filtration removed 71% of BDON in ozonated water. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Effects of gamma irradiation and ozone treatment on microbial decontamination and fatty acid compositions of aloe and pollen powders

    International Nuclear Information System (INIS)

    Yook, H.S.; Chung, Y.J.; Kim, J.O.; Kwon, O.J.; Byun, M.W.

    1997-01-01

    The comparative effects of gamma irradiation and ozone treatment on the microbial inactivation and fatty acid composition were investigated for improving hygienic quality of aloe and pollen powders. Gamma irradiation at 10 kGy resulted in sterilizing total aerobic bacteria, molds and coliforms below detective levels, while ozone treatment for 8 hours up to 18 ppm did not sufficiently eliminate the microorganisms of aloe and pollen powders. The compositions of fatty acid were not significantly changed by gamma irradiation up to 10 kGy. However, ozone treatment markedly decreased unsaturated fatty acids by approximately 20-80% in contents, whereas it significantly increased saturated fatty acids (p<0.05)

  4. Effect of ozone treatment on the optical and electrical properties of HfSiO thin films

    International Nuclear Information System (INIS)

    Geng, Yang; Yang, Wen; Zhu, Shang-Bin; Zhang, Yuan; Sun, Qing-Qing; Lu, Hong-Liang; Zhang, David Wei

    2014-01-01

    The effect of room temperature ozone oxidation treatment on thin HfSiO film grown by atomic layer deposition (ALD) has been investigated. The optical and electrical properties with different post-ozone oxidation time were characterized. The evolution of ozone interacting with HfSiO films was clearly illuminated. Ozone can repair the lossy chemical bonds and vacancies, resulting in the improvement of packing density and polarizability of HfSiO films. With more ozone entering the HfSiO films, the refractive index, dielectric constant, and interfacial properties can be greatly upgraded. Furthermore, the frequency dispersion of ALD-HfSiO film can be improved after O 3 treatment time for 8 min. (orig.)

  5. Randomised, double-blinded, placebo-controlled, clinical trial of ozone therapy as treatment of sudden sensorineural hearing loss.

    Science.gov (United States)

    Ragab, A; Shreef, E; Behiry, E; Zalat, S; Noaman, M

    2009-01-01

    To investigate the safety and efficacy of ozone therapy in adult patients with sudden sensorineural hearing loss. Prospective, randomised, double-blinded, placebo-controlled, parallel group, clinical trial. Forty-five adult patients presented with sudden sensorineural hearing loss, and were randomly allocated to receive either placebo (15 patients) or ozone therapy (auto-haemotherapy; 30 patients). For the latter treatment, 100 ml of the patient's blood was treated immediately with a 1:1 volume, gaseous mixture of oxygen and ozone (from an ozone generator) and re-injected into the patient by intravenous infusion. Treatments were administered twice weekly for 10 sessions. The following data were recorded: pre- and post-treatment mean hearing gains; air and bone pure tone averages; speech reception thresholds; speech discrimination scores; and subjective recovery rates. Significant recovery was observed in 23 patients (77 per cent) receiving ozone treatment, compared with six (40 per cent) patients receiving placebo (p < 0.05). Mean hearing gains, pure tone averages, speech reception thresholds and subjective recovery rates were significantly better in ozone-treated patients compared with placebo-treated patients (p < 0.05). Ozone therapy is a significant modality for treatment of sudden sensorineural hearing loss; no complications were observed.

  6. Integrated modeling of ozonation for optimization of drinking water treatment

    NARCIS (Netherlands)

    van der Helm, A.W.C.

    2007-01-01

    Drinking water treatment plants automation becomes more sophisticated, more on-line monitoring systems become available and integration of modeling environments with control systems becomes easier. This gives possibilities for model-based optimization. In operation of drinking water treatment

  7. Effect of ozonation on the removal of cyanobacterial toxins during drinking water treatment.

    Science.gov (United States)

    Hoeger, Stefan J; Dietrich, Daniel R; Hitzfeld, Bettina C

    2002-01-01

    Water treatment plants faced with toxic cyanobacteria have to be able to remove cyanotoxins from raw water. In this study we investigated the efficacy of ozonation coupled with various filtration steps under different cyanobacterial bloom conditions. Cyanobacteria were ozonated in a laboratory-scale batch reactor modeled on a system used by a modern waterworks, with subsequent activated carbon and sand filtration steps. The presence of cyanobacterial toxins (microcystins) was determined using the protein phosphatase inhibition assay. We found that ozone concentrations of at least 1.5 mg/L were required to provide enough oxidation potential to destroy the toxin present in 5 X 10(5 )Microcystis aeruginosa cells/mL [total organic carbon (TOC), 1.56 mg/L]. High raw water TOC was shown to reduce the efficiency of free toxin oxidation and destruction. In addition, ozonation of raw waters containing high cyanobacteria cell densities will result in cell lysis and liberation of intracellular toxins. Thus, we emphasize that only regular and simultaneous monitoring of TOC/dissolved organic carbon and cyanobacterial cell densities, in conjunction with online residual O(3) concentration determination and efficient filtration steps, can ensure the provision of safe drinking water from surface waters contaminated with toxic cyanobacterial blooms. PMID:12417484

  8. Micropollutant removal during biological wastewater treatment and a subsequent ozonation step

    Energy Technology Data Exchange (ETDEWEB)

    Schaar, Heidemarie, E-mail: hschaar@iwag.tuwien.ac.a [Institute of Water Quality, Resources and Waste Management, Vienna University of Technology, Karlsplatz 13/226, 1040 Vienna (Austria); Clara, Manfred; Gans, Oliver [Umweltbundesamt, Spittelauer Lande 5, 1090 Vienna (Austria); Kreuzinger, Norbert [Institute of Water Quality, Resources and Waste Management, Vienna University of Technology, Karlsplatz 13/226, 1040 Vienna (Austria)

    2010-05-15

    The design criteria for wastewater treatment plants (WWTP) and the sludge retention time, respectively, have a significant impact on micropollutant removal. The upgrade of an Austrian municipal WWTP to nitrogen removal (best available technology, BAT) resulted in increased elimination of most of the analyzed micropollutants. Substances, such as bisphenol-A, 17alpha-ethinylestradiol and the antibiotics erythromycin and roxithromycin were only removed after the upgrade of the WWTP. Nevertheless, the BAT was not sufficient to completely eliminate these compounds. Thus, a pilot scale ozonation plant was installed for additional treatment of the effluent. The application of 0.6 g O{sub 3} g DOC{sup -1} increased the removal of most of the micropollutants, especially for compounds that were not degraded in the previous biological process, as for example carbamazepine and diclofenac. These results indicated that the ozonation of WWTP effluent is a promising technology to further decrease emissions of micropollutants from the treatment process. - SRT is an important criterion for micropollutant removal in wastewater treatment and the application of ozone is suitable for further removal of micropollutants.

  9. Micropollutant removal during biological wastewater treatment and a subsequent ozonation step

    International Nuclear Information System (INIS)

    Schaar, Heidemarie; Clara, Manfred; Gans, Oliver; Kreuzinger, Norbert

    2010-01-01

    The design criteria for wastewater treatment plants (WWTP) and the sludge retention time, respectively, have a significant impact on micropollutant removal. The upgrade of an Austrian municipal WWTP to nitrogen removal (best available technology, BAT) resulted in increased elimination of most of the analyzed micropollutants. Substances, such as bisphenol-A, 17α-ethinylestradiol and the antibiotics erythromycin and roxithromycin were only removed after the upgrade of the WWTP. Nevertheless, the BAT was not sufficient to completely eliminate these compounds. Thus, a pilot scale ozonation plant was installed for additional treatment of the effluent. The application of 0.6 g O 3 g DOC -1 increased the removal of most of the micropollutants, especially for compounds that were not degraded in the previous biological process, as for example carbamazepine and diclofenac. These results indicated that the ozonation of WWTP effluent is a promising technology to further decrease emissions of micropollutants from the treatment process. - SRT is an important criterion for micropollutant removal in wastewater treatment and the application of ozone is suitable for further removal of micropollutants.

  10. Integrated ozonation and biomethanization treatments of vinasse derived from ethanol manufacturing

    International Nuclear Information System (INIS)

    Siles, J.A.; Garcia-Garcia, I.; Martin, A.; Martin, M.A.

    2011-01-01

    Anaerobic digestion of vinasse derived from bioethanol manufacturing, in which total COD was found to be 68.56 ± 8.17 g/L, was studied in batch laboratory-scale reactors at mesophilic temperature (35 deg. C). The vinasse was subjected to a short ozonation pre-treatment (15 min) in which more than 50% reduction of phenols was observed, although the total organic carbon concentration remained approximately stable, indicating that the phenols were transformed into other simpler forms. The anaerobic biodegradability of raw and pre-treated vinasse was similar, reaching values close to 80% (COD). However, the methane yield coefficient and methane production rate enhanced by around 13.6% and 41.16%, respectively, when the ozonized vinasse was fed. These results indicate that the integration of chemical-biological treatments could be a viable option for the purification of this hazardous wastewater.

  11. Dielectric Barrier Discharge Plasma-Induced Photocatalysis and Ozonation for the Treatment of Wastewater

    International Nuclear Information System (INIS)

    Sun, Mok Young; Jin-Oh, Jo; Heon-Ju, Lee

    2008-01-01

    The physicochemical processes of dielectric barrier discharge (DBD) such as in-situ formation of chemically active species and emission of ultraviolet (UV)/visible light were utilized for the treatment of a simulated wastewater formed with Acid Red 4 as the model organic contaminant. The chemically active species (mostly ozone) produced in the DBD reactor were well distributed in the wastewater using a porous gas diffuser, thereby increasing the gas-liquid contact area. For the purpose of making the best use of the light emission, a titanium oxide-based photocatalyst was incorporated in the wastewater treating system. The experimental parameters chosen were the voltage applied to the DBD reactor, the initial pH of the wastewater, and the concentration of hydrogen peroxide added to the wastewater. The results have clearly shown that the present system capable of degrading organic contaminants in two ways (photocatalysis and ozonation) may be a promising wastewater treatment technology.

  12. Dielectric Barrier Discharge Plasma-Induced Photocatalysis and Ozonation for the Treatment of Wastewater

    Science.gov (United States)

    Mok, Young Sun; Jo, Jin-Oh; Lee, Heon-Ju

    2008-02-01

    The physicochemical processes of dielectric barrier discharge (DBD) such as in-situ formation of chemically active species and emission of ultraviolet (UV)/visible light were utilized for the treatment of a simulated wastewater formed with Acid Red 4 as the model organic contaminant. The chemically active species (mostly ozone) produced in the DBD reactor were well distributed in the wastewater using a porous gas diffuser, thereby increasing the gas-liquid contact area. For the purpose of making the best use of the light emission, a titanium oxide-based photocatalyst was incorporated in the wastewater treating system. The experimental parameters chosen were the voltage applied to the DBD reactor, the initial pH of the wastewater, and the concentration of hydrogen peroxide added to the wastewater. The results have clearly shown that the present system capable of degrading organic contaminants in two ways (photocatalysis and ozonation) may be a promising wastewater treatment technology.

  13. Electron beam treatment of wastewater

    International Nuclear Information System (INIS)

    Arai, H.; Hosono, M.; Shimizu, K.; Sugiyama, M.

    1991-01-01

    Supernatant comes from dewaterization of sewage sludge, and contains biologically nondegradable organics so that it is hard to be treated by conventional activated sludge. By electron beam (EB) irradiation, any kinds of organics in water can be oxidized to biodegradable organic acids. We studied the treatment of supernatant by application of this effect. The direct irradiation of the original supernatant was found not to be so effective to decrease COD. In order to increase the irradiation effect, supernatant was pretreated biologically to decrease the biodegradable organics in it. The chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were decreased from 800 and 910 mg/L to 78 and 5 mg/L by this pretreatment, respectively. This pretreated supernatant was irradiated by EB of 2 MeV using a batch type reactor. The COD was gradually decreased with dose. In contrast, BOD was increased markedly, indicating increase in biodegradability. The irradiated sample water was treated biologically again. After the final biological treatment, COD was decreased below 30 mg/L in the case of 10 - 12 kGy irradiation. Finally, the initial COD of 800 mg/L was decreased below 30 mg/L by the combination of EB irradiation and biological treatment. The cost of irradiation for this process was evaluated preliminarily. (author)

  14. Removal of color and chemical oxygen demand using a coupled coagulation-electrocoagulation-ozone treatment of industrial wastewater that contains offset printing dyes

    International Nuclear Information System (INIS)

    Roa M, G.; Barrera D, C.; Balderas H, P.; Zaldumbide O, F.; Reyes P, H.; Bilyeu, B.

    2014-01-01

    Industrial offset printing processes generate wastewater with highly colored obtaining values of 5 x 10 6 Pt-Co units and great values of chemical oxygen demand (COD) 5.3 x 10 -5 mg L -1 . Thus, conventional technologies such as biologicals treatment fail in reaching the discharge limits. In this research, a sequential treatment was applied: coagulation with aluminum hydroxychloride (AHC), electrocoagulation with Al anodes and finally ozonation. Optimal conditions are found when adding 20 mg L -1 AHC, followed by electrocoagulation at 4 A for 50 min, and finally alkaline ozonation for 15 min, resulting in an overall color removal of 99.99% color and 99.35 COD. The sludge generated by the coagulation process was analyzed by scanning electron microscopy and energy dispersive X-ray (EDX) microanalysis. (Author)

  15. Removal of color and chemical oxygen demand using a coupled coagulation-electrocoagulation-ozone treatment of industrial wastewater that contains offset printing dyes

    Energy Technology Data Exchange (ETDEWEB)

    Roa M, G.; Barrera D, C.; Balderas H, P.; Zaldumbide O, F. [Centro Conjunto de Investigacion en Quimica Sustentable UAEM-UNAM, Km 14.5 Carretera Toluca-Atlacomulco, 50200 San Cayetano-Toluca, Estado de Mexico (Mexico); Reyes P, H. [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon y Paseo Tollocan s/n, 50120 Toluca, Estado de Mexico (Mexico); Bilyeu, B., E-mail: groam@uaemex.mx [Xavier University of Louisiana, Department of Chemistry, 1 Drexel Drive, New Orleans, LA 70125 (United States)

    2014-07-01

    Industrial offset printing processes generate wastewater with highly colored obtaining values of 5 x 10{sup 6}Pt-Co units and great values of chemical oxygen demand (COD) 5.3 x 10{sup -5} mg L{sup -1}. Thus, conventional technologies such as biologicals treatment fail in reaching the discharge limits. In this research, a sequential treatment was applied: coagulation with aluminum hydroxychloride (AHC), electrocoagulation with Al anodes and finally ozonation. Optimal conditions are found when adding 20 mg L{sup -1} AHC, followed by electrocoagulation at 4 A for 50 min, and finally alkaline ozonation for 15 min, resulting in an overall color removal of 99.99% color and 99.35 COD. The sludge generated by the coagulation process was analyzed by scanning electron microscopy and energy dispersive X-ray (EDX) microanalysis. (Author)

  16. Removal of total and antibiotic resistant bacteria in advanced wastewater treatment by ozonation in combination with different filtering techniques.

    Science.gov (United States)

    Lüddeke, Frauke; Heß, Stefanie; Gallert, Claudia; Winter, Josef; Güde, Hans; Löffler, Herbert

    2015-02-01

    Elimination of bacteria by ozonation in combination with charcoal or slow sand filtration for advanced sewage treatment to improve the quality of treated sewage and to reduce the potential risk for human health of receiving surface waters was investigated in pilot scale at the sewage treatment plant Eriskirch, Baden-Wuerttemberg/Germany. To determine the elimination of sewage bacteria, inflowing and leaving wastewater of different treatment processes was analysed in a culture-based approach for its content of Escherichia coli, enterococci and staphylococci and their resistance against selected antibiotics over a period of 17 month. For enterococci, single species and their antibiotic resistances were identified. In comparison to the established flocculation filtration at Eriskirch, ozonation plus charcoal or sand filtration (pilot-scale) reduced the concentrations of total and antibiotic resistant E. coli, enterococci and staphylococci. However, antibiotic resistant E. coli and staphylococci apparently survived ozone treatment better than antibiotic sensitive strains. Neither vancomycin resistant enterococci nor methicillin resistant Staphylococcus aureus (MRSA) were detected. The decreased percentage of antibiotic resistant enterococci after ozonation may be explained by a different ozone sensitivity of species: Enterococcus faecium and Enterococcus faecalis, which determined the resistance-level, seemed to be more sensitive for ozone than other Enterococcus-species. Overall, ozonation followed by charcoal or sand filtration led to 0.8-1.1 log-units less total and antibiotic resistant E. coli, enterococci and staphylococci, as compared to the respective concentrations in treated sewage by only flocculation filtration. Thus, advanced wastewater treatment by ozonation plus charcoal or sand filtration after common sewage treatment is an effective tool for further elimination of microorganisms from sewage before discharge in surface waters. Copyright © 2014 Elsevier

  17. Novel pre-treatments to control bromate formation during ozonation

    DEFF Research Database (Denmark)

    Antoniou, Maria; Sichel, Cosima; Andre, Klaus

    2017-01-01

    Worldwide water shortage increase and water quality depletion from microbial and chemical compounds, pose significant challenges for today’s water treatment industry. Both the development of new advanced oxidation technologies, but also the enhancement of existing conventional technologies is of ...

  18. Ozone treatment of polysaccharides from Arthrocnemum indicum: Physico-chemical characterization and antiproliferative activity.

    Science.gov (United States)

    Mzoughi, Zeineb; Chakroun, Ibtissem; Hamida, Sarra Ben; Rihouey, Christophe; Mansour, Hedi Ben; Le Cerf, Didier; Majdoub, Hatem

    2017-12-01

    The isolation, purification and ozone depolymerization of polysaccharides from Arthrocnemum indicum as well as the evaluation of their antiproliferative capacities were investigated. The ozone treatment for various reaction times (0, 15, 30, 45 and 60min) was employed as degradation method in order to attain lower molecular weight product with stronger antiproliferative property. According to FTIR, 1 H NMR and UV-vis analysis, the main chain of ozonolytic degraded polysaccharides could be preserved. The monosaccharide composition, which was determined via GC/MS analysis, showed that extracted polysaccharides were of type of arabinan-rich pectic polysaccharides. Macromolecular characteristics as well as intrinsic viscosity of the degraded polysaccharides were performed by size exclusion chromatography before and after ozone treatment. These experiments showed that intrinsic viscosity and molecular weight (Mn and Mw) of degraded samples decreased with increase in reaction time. Furthermore, preliminary antiproliferative tests indicated that degraded polysaccharide for 1h showed even better antiproliferative capacity. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Application of Ozone and Granular Activated Carbon for Distillery Effluent Treatment

    Directory of Open Access Journals (Sweden)

    Mojtaba Hadavifar

    2010-06-01

    Full Text Available The main objective of this study was to investigate the treatment of distillery vinasse through the integrated process of ozone oxidation and Granular Activated Carbon (GAC in a continuous process. The continuous process was carried out both by each of the GAC and ozone processes alone and by the combination of the two in order to investigate the synergistic effects of the two modes on COD and color removal in the treatment of vinasse from laboratory ethanol production from cane molasses. The continuous processes were performed at an ozone generation rate of 240mg/h, GAC dose of 100g, and at room temperature (25°C. Color removal efficiency of O3 was higher than its COD removal from vinasse. The COD and color removal efficiencies of the O3 process were about 25% and 74%, respectively. Moreover, GAC/O3 process was found to negatively affect the synergy of COD and color removal efficiency from distillery vinasse. This negative effect decreased by increasing influent pH level. The results indicate that the initial pH has a considerable effect on the three processes investigated.

  20. Field-analysis of potable water quality and ozone efficiency in ozone-assisted biological filtration systems for surface water treatment.

    Science.gov (United States)

    Zanacic, Enisa; Stavrinides, John; McMartin, Dena W

    2016-11-01

    Potable water treatment in small communities is challenging due to a complexity of factors starting with generally poor raw water sources, a smaller tax and consumption base that limit capital and operating funds, and culminating in what is typically a less sophisticated and robust water treatment plant for production and delivery of safe, high quality potable water. The design and optimization of modular ozone-assisted biological filtration systems can address some of these challenges. In surface water treatment, the removal of organic matter (e.g., dissolved organic carbon - DOC), inorganic nutrients and other exposure-related contaminants (e.g., turbidity and dissolved solids) from the raw water source is essential. Thus, a combination of chemical and biological oxidation processes can produce an effective and efficient water treatment plant design that is also affordable and robust. To that end, the ozone-assisted biological filtration water treatment plants in two communities were evaluated to determine the efficacy of oxidation and contaminant removal processes. The results of testing for in-field system performance indicate that plant performance is particularly negatively impacted by high alkalinity, high organics loading, and turbidity. Both bicarbonate and carbonate alkalinity were observed to impede ozone contact and interaction with DOC, resulting in lower than anticipated DOC oxidation efficiency and bioavailability. The ozone dosage at both water treatment plants must be calculated on a more routine basis to better reflect both the raw water DOC concentration and presence of alkalinities to ensure maximized organics oxidation and minimization of trihalomethanes production. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Compatibility of the ultraviolet light-ozone system for laundry waste water treatment in nuclear power plants

    International Nuclear Information System (INIS)

    Matsuo, Toshiaki; Nishi, Takashi; Matsuda, Masami; Izumida, Tatsuo

    1997-01-01

    As an alternative treatment system for laundry waste water in nuclear power plants, a system was chosen in which such organic compounds as surfactant would be oxidized by ultraviolet (UV) light and ozone. The system compatibility, UV light source, and dissolved ozone concentration were examined through experiments. First, ozone gas was absorbed in the waste water. After the dissolved ozone concentration equilibrated at the desired value, the waste water was irradiated by a mercury lamp. Then, the time dependence of the concentrations of the organic compounds, the dissolved ozone, and the hydrogen peroxide were measured to estimate the treatment rate of the system. The mercury lamp with a 10 5 -Pa vapor pressure achieved large UV radiation and a treatment rate increase, leading to a compatible system without secondary waste generation. The effect of the dissolved ozone concentration on the treatment rate was saturated when concentration was >3.3 x 10 -4 mol/10 -3 m 3 at the time UV radiation was started. Numerical results indicated the saturation was due to hydrogen peroxide generation, which prevents hydroxyl radical generation

  2. Highly reproducible and reliable metal/graphene contact by ultraviolet-ozone treatment

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wei [Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing 100871 (China); Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Hacker, Christina A.; Cheng, Guangjun; Hight Walker, A. R.; Richter, Curt A.; Gundlach, David J., E-mail: david.gundlach@nist.gov, E-mail: liangxl@pku.edu.cn [Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Liang, Yiran; Tian, Boyuan; Liang, Xuelei, E-mail: david.gundlach@nist.gov, E-mail: liangxl@pku.edu.cn; Peng, Lianmao [Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing 100871 (China)

    2014-03-21

    Resist residue from the device fabrication process is a significant source of contamination at the metal/graphene contact interface. Ultraviolet Ozone (UVO) treatment is proven here, by X-ray photoelectron spectroscopy and Raman measurement, to be an effective way of cleaning the metal/graphene interface. Electrical measurements of devices that were fabricated by using UVO treatment of the metal/graphene contact region show that stable and reproducible low resistance metal/graphene contacts are obtained and the electrical properties of the graphene channel remain unaffected.

  3. Highly reproducible and reliable metal/graphene contact by ultraviolet-ozone treatment

    International Nuclear Information System (INIS)

    Li, Wei; Hacker, Christina A.; Cheng, Guangjun; Hight Walker, A. R.; Richter, Curt A.; Gundlach, David J.; Liang, Yiran; Tian, Boyuan; Liang, Xuelei; Peng, Lianmao

    2014-01-01

    Resist residue from the device fabrication process is a significant source of contamination at the metal/graphene contact interface. Ultraviolet Ozone (UVO) treatment is proven here, by X-ray photoelectron spectroscopy and Raman measurement, to be an effective way of cleaning the metal/graphene interface. Electrical measurements of devices that were fabricated by using UVO treatment of the metal/graphene contact region show that stable and reproducible low resistance metal/graphene contacts are obtained and the electrical properties of the graphene channel remain unaffected

  4. Ozone-augmented percutaneous discectomy: A novel treatment option for refractory discogenic sciatica

    International Nuclear Information System (INIS)

    Crockett, M.T.; Moynagh, M.; Long, N.; Kilcoyne, A.; Dicker, P.; Synnott, K.; Eustace, S.J.

    2014-01-01

    Aim: To assess the short and medium-term efficacy and safety of a novel, minimally invasive therapeutic option combining automated percutaneous lumbar discectomy, intradiscal ozone injection, and caudal epidural: ozone-augmented percutaneous discectomy (OPLD). Materials and methods: One hundred and forty-seven patients with a clinical and radiological diagnosis of discogenic sciatica who were refractory to initial therapy were included. Fifty patients underwent OPLD whilst 97 underwent a further caudal epidural. Outcomes were evaluated using McNab's score, improvement in visual analogue score (VAS) pain score, and requirement for further intervention. Follow-up occurred at 1 and 6 months, and comparison was made between groups. Results: OPLD achieved successful outcomes in almost three-quarters of patients in the short and medium term. OPLD achieved superior outcomes at 1 and 6 months compared to caudal epidural. There was a reduced requirement for further intervention in the OPLD group. No significant complications occurred in either group. Discussion: OPLD is a safe and effective treatment for patients with refractory discogenic sciatica in the short and medium term. OPLD has the potential to offer an alternative second-line minimally invasive treatment option that could reduce the requirement for surgery in this patient cohort. - Highlights: • Discogenic sciatica is a common condition which causes significant morbidity. • Ozone augmented percutaneous lumbar discectomy (OPLD) is a novel treatment. • Comparison was made to caudal epidural injection. • All outcomes were superior in the OPLD treatment group. • OPLD appears is an effective treatment for refractory discogenic sciatica

  5. Efficiency of combined process of ozone and bio-filtration in the treatment of secondary effluent.

    Science.gov (United States)

    Tripathi, Smriti; Tripathi, B D

    2011-07-01

    The present work was aimed at studying the efficiency of the combined process of biofiltration with ozonation to improve the quality of secondary effluent. The secondary effluent from the Dinapur Sewage Treatment Plant Varanasi, India was used in this work. The process of biofiltration with the plant species of Eichornia crassipes and Lemna minor, at a flow rate of 262 ml min(-1) and plant density of 30 mg L(-1) for 48 h, in combination with the process of ozonation with ozone dose of 10 mg L(-1) and contact time of 5 min was applied. Results revealed that combined process was statistically most suitable for the highest degradation of physico-chemical and microbial parameters with improving BDOC value. The biofiltration process is able to remove highest percentage of toxic heavy metals from the secondary effluent without production of toxicity. This technique is highly recommendable for tropical wastewater where sewage is mixed with industrial effluents. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Disinfection efficiency of peracetic acid, UV and ozone after enhanced primary treatment of municipal wastewater.

    Science.gov (United States)

    Gehr, Ronald; Wagner, Monika; Veerasubramanian, Priya; Payment, Pierre

    2003-11-01

    The City of Montreal Wastewater Treatment Plant uses enhanced physicochemical processes (ferric and/or alum coagulation) for suspended solids and phosphorus removal. The objective of this study was to assess the ability of peracetic acid (PAA), UV, or ozone to inactivate the indicator organisms fecal coliforms, Enterococci, MS-2 coliphage, or Clostridium perfringens in the effluent from this plant. PAA doses to reach the target fecal coliform level of 9000 CFU/100mL exceeded 6 mg/L; similar results were obtained for enterococci, and no inactivation of Clostridium perfringens was observed. However a 1-log reduction of MS-2 occurred at PAA doses of 1.5 mg/L and higher. It was expected that this effluent would have a high ozone demand, and would require relatively high UV fluences, because of relatively high effluent COD, iron and suspended solids concentrations, and low UV transmittance. This was confirmed herein. For UV, the inactivation curve for fecal coliforms showed the typical two-stage shape, with the target of 1000 CFU/100 mL (to account for photoreactivation) occurring in the asymptote zone at fluences >20 mJ/cm(2). In contrast, inactivation curves for MS-2 and Clostridium perfringens were linear. Clostridium perfringens was the most resistant organism. For ozone, inactivation was already observed before any residuals could be measured. The transferred ozone doses to reach target fecal coliform levels ( approximately 2-log reduction) were 30-50 mg/L. MS-2 was less resistant, but Clostridium perfringens was more resistant than fecal coliforms. The different behaviour of the four indicator organisms studied, depending on the disinfectant, suggests that a single indicator organism might not be appropriate. The required dose of any of the disinfectants is unlikely to be economically viable, and upstream changes to the plant will be needed.

  7. Ozonation and thermal pre-treatment of municipal sewage sludge – Implications for toxicity and methane potential

    DEFF Research Database (Denmark)

    Davidsson, A.; Eriksson, Eva; Fick, J.

    The aim of this study was to determine the effects on the methane potential and the overall sludge quality from two different sludge pre-treatment technologies (ozonation high/low dosage and thermal treatment 55/70 °C). In general both treatments gave an increased methane potential. The thermal t...... treatment resulted in higher chemical oxygen demand (COD)-solubilisation, while the highest volatile fatty acids (VFA) increase was obtained with ozonation. The sludges had inhibiting effects in a barley seed germination assay and a yeast oestrogen screen both before and after pre...

  8. Combined UV treatment and ozonation for the removal of by-product precursors in swimming pool water

    DEFF Research Database (Denmark)

    Cheema, Waqas Akram; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2017-01-01

    Both UV treatment and ozonation are used to reduce different types of disinfection by-products (DBPs) in swimming pools. UV treatment is the most common approach, as it is particularly efficient at removing combined chlorine. However, the UV treatment of pool water increases chlorine reactivity...

  9. Sum frequency generation and catalytic reaction studies of the removal of the organic capping agents from Pt nanoparticles by UV-ozone treatment

    Energy Technology Data Exchange (ETDEWEB)

    Aliaga, Cesar; Park, Jeong Y.; Yamada, Yusuke; Lee, Hyun Sook; Tsung, Chia-Kuang; Yang, Peidong; Somorjai, Gabor A.

    2009-12-10

    We report the structure of the organic capping layers of platinum colloid nanoparticles and their removal by UV-ozone exposure. Sum frequency generation vibrational spectroscopy (SFGVS) studies identify the carbon-hydrogen stretching modes on poly(vinylpyrrolidone) (PVP) and tetradecyl tributylammonium bromide (TTAB)-capped platinum nanoparticles. We found that the UV-ozone treatment technique effectively removes the capping layer on the basis of several analytical measurements including SFGVS, X-ray photoelectron spectroscopy, and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The overall shape of the nanoparticles was preserved after the removal of capping layers, as confirmed by transmission electron microscopy (TEM). SFGVS of ethylene hydrogenation on the clean platinum nanoparticles demonstrates the existence of ethylidyne and di-{sigma}-bonded species, indicating the similarity between single-crystal and nanoparticle systems.

  10. Ozone Treatment of Alveolar Bone in the Cape Chacma Baboon Does Not Enhance Healing Following Trauma

    OpenAIRE

    Kotze, Marthinus; Bütow, Kürt-W; Olorunju, Steve A.; Kotze, Harry F.

    2013-01-01

    In the international literature, the role of Ozone (O3) in the advancement in alveolar bone healing in the absence of bone pathology was not tested before. The purpose of this study was to evaluate alveolar bone regeneration after a bone defect was created and treated with a single topical administration of O3. Alveolar bone defects were created on five healthy chacma baboons. One side of the maxilla and mandible was topically treated with a single treatment of an O3/O2 mixture (3,5–4 % O3), ...

  11. Evaluation of pre-treatments for inhibiting bromate formation during ozonation

    DEFF Research Database (Denmark)

    Antoniou, Maria; Andersen, Henrik Rasmus

    2011-01-01

    This study compared several pre-treatment methods for inhibiting BrO3- formation during ozonation of tap water, from the DTU campus, including H2O2 addition (perozone), pH-depression, NH4+ and Cl2/NH4+ addition. At the same time, the inhibition of atrazine and carbamazepine removal was evaluated...... close to the 10 μg/L limit, however atrazine removal did not exceed 75%. Carbamazepine was completely removed under all the tested experimental conditions with the 3.5 mg/L O3 dose....

  12. Medical ozone therapy as a potential treatment modality for regeneration of damaged articular cartilage in osteoarthritis

    Directory of Open Access Journals (Sweden)

    Sello Lebohang Manoto

    2018-05-01

    Full Text Available Osteoarthritis (OA is the most common degenerative joint disease and a growing health problem affecting more than half of the population over the age of 65. It is characterized by inflammation in the cartilage and synovium, resulting in the loss of joint structure and progressive damage to the cartilage. Many pro-inflammatory mediators are elevated in OA, including reactive oxygen species (ROS such as nitric oxide (NO and hydrogen peroxide (H2O2. Damaged articular cartilage remains a challenge to treat due to the limited self-healing capacity of the tissue and unsuccessful biological interventions. This highlights the need for better therapeutic strategies to heal damaged articular cartilage. Ozone (O3 therapy has been shown to have positive results in the treatment of OA; however the use of O3 therapy as a therapeutic agent is controversial. There is a perception that O3 is always toxic, whereas evidence indicates that when it is applied following a specified method, O3 can be effective in the treatment of degenerative diseases. The mechanism of action of O3 therapy in OA is not fully understood and this review summarizes the use of O3 therapy in the treatment of damaged articular cartilage in OA. Keywords: Osteoarthritis (OA, Articular cartilage, Ozone (O3 therapy, Reactive oxygen species (ROS

  13. Occurrence of emerging pollutants in urban wastewater and their removal through biological treatment followed by ozonation.

    Science.gov (United States)

    Rosal, Roberto; Rodríguez, Antonio; Perdigón-Melón, José Antonio; Petre, Alice; García-Calvo, Eloy; Gómez, María José; Agüera, Ana; Fernández-Alba, Amadeo R

    2010-01-01

    This work reports a systematic survey of over seventy individual pollutants in a Sewage Treatment Plant (STP) receiving urban wastewater. The compounds include mainly pharmaceuticals and personal care products, as well as some metabolites. The quantification in the ng/L range was performed by Liquid Chromatography-QTRAP-Mass Spectrometry and Gas Chromatography coupled to Mass Spectrometry. The results showed that paraxanthine, caffeine and acetaminophen were the main individual pollutants usually found in concentrations over 20 ppb. N-formyl-4-amino-antipiryne and galaxolide were also detected in the ppb level. A group of compounds including the beta-blockers atenolol, metoprolol and propanolol; the lipid regulators bezafibrate and fenofibric acid; the antibiotics erythromycin, sulfamethoxazole and trimethoprim, the antiinflammatories diclofenac, indomethacin, ketoprofen and mefenamic acid, the antiepileptic carbamazepine and the antiacid omeprazole exhibited removal efficiencies below 20% in the STP treatment. Ozonation with doses lower than 90 microM allowed the removal of many individual pollutants including some of those more refractory to biological treatment. A kinetic model allowed the determination of second order kinetic constants for the ozonation of bezafibrate, cotinine, diuron and metronidazole. The results show that the hydroxyl radical reaction was the major pathway for the oxidative transformation of these compounds. (c) 2009 Elsevier Ltd. All rights reserved.

  14. Textile wastewater treatment: colour and COD removal of reactive black-5 by ozonation

    Science.gov (United States)

    Suryawan, I. W. K.; Helmy, Q.; Notodarmojo, S.

    2018-01-01

    Textile industries produced a large amount of highly coloured wastewater containing variety of dyes in different concentrations. Due to the high concentration of organics in the effluents and the higher stability of modern synthetic dyes, the conventional biological treatment methods are ineffective for the complete colour removal and degradation of organics and dyes. On the other hand, physical-chemical treatment are not destructive, mainly just concentrate and separate the pollutants phases. This research paper investigates the removal of colour and chemical oxygen demand/COD from textile wastewater using ozone treatment. Varied ozone dosages of 1.16; 3.81; 18.79; and 40.88 mg/minute were used in the experiment. Varied wastewater containing Reactive Black 5 (RB-5) concentrations of 40 mg/L, 100 mg/L were also applied. Research result showed the highest colour removal efficiency of 96.9 % was achieved after 5 hours incubation time, while the highest COD removal efficiency of 77.5% was achieved after 2 hours incubation time.

  15. Observation of abnormal mobility enhancement in multilayer MoS2 transistor by synergy of ultraviolet illumination and ozone plasma treatment

    Science.gov (United States)

    Guo, Junjie; Yang, Bingchu; Zheng, Zhouming; Jiang, Jie

    2017-03-01

    Mobility engineering through physical or chemical process is a fruitful approach for the atomically-layered two-dimensional electronic applications. Unfortunately, the usual process with either illumination or oxygen treatment would greatly deteriorate the mobility in two-dimensional MoS2 field-effect transistor (FET). Here, in this work, we report that the mobility can be abnormally enhanced to an order of magnitude by the synergy of ultraviolet illumination (UV) and ozone plasma treatment in multilayer MoS2 FET. This abnormal mobility enhancement is attributed to the trap passivation due to the photo-generated excess carriers during UV/ozone plasma treatment. An energy band model based on Schottky barrier modulation is proposed to understand the underlying mechanism. Raman spectra results indicate that the oxygen ions are incorporated into the surface of MoS2 (some of them are in the form of ultra-thin Mo-oxide) and can further confirm this proposed mechanism. Our results can thus provide a simple approach for mobility engineering in MoS2-based FET and can be easily expanded to other 2D electronic devices, which represents a significant step toward applications of 2D layered materials in advanced cost-effective electronics.

  16. Remedial Process Optimization and Green In-Situ Ozone Sparging for Treatment of Groundwater Impacted with Petroleum Hydrocarbons

    Science.gov (United States)

    Leu, J.

    2012-12-01

    A former natural gas processing station is impacted with TPH and BTEX in groundwater. Air sparging and soil vapor extraction (AS/AVE) remediation systems had previously been operated at the site. Currently, a groundwater extraction and treatment system is operated to remove the chemicals of concern (COC) and contain the groundwater plume from migrating offsite. A remedial process optimization (RPO) was conducted to evaluate the effectiveness of historic and current remedial activities and recommend an approach to optimize the remedial activities. The RPO concluded that both the AS/SVE system and the groundwater extraction system have reached the practical limits of COC mass removal and COC concentration reduction. The RPO recommended an in-situ chemical oxidation (ISCO) study to evaluate the best ISCO oxidant and approach. An ISCO bench test was conducted to evaluate COC removal efficiency and secondary impacts to recommend an application dosage. Ozone was selected among four oxidants based on implementability, effectiveness, safety, and media impacts. The bench test concluded that ozone demand was 8 to 12 mg ozone/mg TPH and secondary groundwater by-products of ISCO include hexavalent chromium and bromate. The pH also increased moderately during ozone sparging and the TDS increased by approximately 20% after 48 hours of ozone treatment. Prior to the ISCO pilot study, a capture zone analysis (CZA) was conducted to ensure containment of the injected oxidant within the existing groundwater extraction system. The CZA was conducted through a groundwater flow modeling using MODFLOW. The model indicated that 85%, 90%, and 95% of an injected oxidant could be captured when a well pair is injecting and extracting at 2, 5, and 10 gallons per minute, respectively. An ISCO pilot test using ozone was conducted to evaluate operation parameters for ozone delivery. The ozone sparging system consisted of an ozone generator capable of delivering 6 lbs/day ozone through two ozone

  17. Electron beam treatment of industrial wastewater

    International Nuclear Information System (INIS)

    Han, Bumsoo; Kim, JinKyu; Kim, Yuri

    2004-01-01

    For industrial wastewater with low impurity levels such as contaminated ground water, cleaning water and etc., purification only with electron beam is possible, but it should be managed carefully with reducing required irradiation doses as low as possible. Also for industrial wastewater with high impurity levels such as dyeing wastewater, leachate and etc., purification only with electron beam requires high amount of doses and far beyond economies. Electron beam treatment combined with conventional purification methods such as coagulation, biological treatment, etc. is suitable for reduction of non-biodegradable impurities in wastewater and will extend the application area of electron beam. A pilot plant with electron beam for treating 1,000 m 3 /day of wastewater from dyeing industries has constructed and operated continuously since Oct 1998. Electron beam irradiation instead of chemical treatment shows much improvement in removing impurities and increases the efficiency of biological treatment. Actual plant is under consideration based upon the experimental results. (author)

  18. Ozone therapy as add-on treatment in fibromyalgia management by rectal insufflation: an open-label pilot study.

    Science.gov (United States)

    Hidalgo-Tallón, Javier; Menéndez-Cepero, Silvia; Vilchez, Juan S; Rodríguez-López, Carmen M; Calandre, Elena P

    2013-03-01

    The objectives of this study were to evaluate the effectiveness and tolerability of ozone therapy by rectal insufflation as add-on therapy in fibromyalgia management. Patients with fibromyalgia received 24 sessions of ozone therapy during a 12-week period. At each session, the administered dose of ozone was 8 mg (200 mL of gas, at a concentration of 40 μg/mL). Ozone sessions were given 5 days a week during the first 2 weeks, twice a week from weeks 3-6, and weekly from weeks 7-12. Fibromyalgia Impact Questionnaire (FIQ) was the main outcome measure, and was administered at baseline and at weeks 4, 8, and 12. Secondary outcome measures, administered at baseline and at endpoint, were the Pittsburgh Sleep Quality Index, the Beck Depression Inventory, the State and Trait Anxiety Inventory, and the SF-12, the abbreviated form of the Short Form Health Survey. Emergent adverse reactions to treatment were recorded. FIQ total scores decreased significantly during the study period, with the decrease being observed in the first 4 weeks of the study. Significant improvement was also seen both in depression scores and in the Physical Summary Score of the SF-12. Transient meteorism after ozone therapy sessions was the most frequently reported side-effect. At the dose and number of sessions used in this study, ozone therapy by rectal insufflation seems to be beneficial for physical symptoms and depression of fibromyalgia.

  19. Membrane contactor/separator for an advanced ozone membrane reactor for treatment of recalcitrant organic pollutants in water

    International Nuclear Information System (INIS)

    Chan, Wai Kit; Jouët, Justine; Heng, Samuel; Yeung, King Lun; Schrotter, Jean-Christophe

    2012-01-01

    An advanced ozone membrane reactor that synergistically combines membrane distributor for ozone gas, membrane contactor for pollutant adsorption and reaction, and membrane separator for clean water production is described. The membrane reactor represents an order of magnitude improvement over traditional semibatch reactor design and is capable of complete conversion of recalcitrant endocrine disrupting compounds (EDCs) in water at less than three minutes residence time. Coating the membrane contactor with alumina and hydrotalcite (Mg/Al=3) adsorbs and traps the organics in the reaction zone resulting in 30% increase of total organic carbon (TOC) removal. Large surface area coating that diffuses surface charges from adsorbed polar organic molecules is preferred as it reduces membrane polarization that is detrimental to separation. - Graphical abstract: Advanced ozone membrane reactor synergistically combines membrane distributor for ozone, membrane contactor for sorption and reaction and membrane separator for clean water production to achieve an order of magnitude enhancement in treatment performance compared to traditional ozone reactor. Highlights: ► Novel reactor using membranes for ozone distributor, reaction contactor and water separator. ► Designed to achieve an order of magnitude enhancement over traditional reactor. ► Al 2 O 3 and hydrotalcite coatings capture and trap pollutants giving additional 30% TOC removal. ► High surface area coating prevents polarization and improves membrane separation and life.

  20. Responses of Dendrobium 'darrenn glory' and Mokara 'calypso jumbo' orchids to 1-methylcyclopropene and aqueous ozone postharvest treatments

    Directory of Open Access Journals (Sweden)

    Parviz Almasi

    2015-01-01

    Full Text Available AbstractOrchids possess a very special place amongst ornamental plants. But high ethylene sensitivity and early flower senescence of orchid result in a short vase life and rapid quality deterioration which is of great concern for the growers, traders and consumers. An attempt was made to study the influence of 1-methylcyclopropene (1-MCP (0 and 300 nL L–1 and аquеous ozone (0 and 5.2 nL L–1 in prolonging vase life and maintaining quality of two cut orchid hybrids Dendrobium 'Darren Glory' (DDG and Mokara “Calypso Jumbo” (MCJ. Results showed that orchid hybrids exhibited differences in their ethylene sensitivity, vase life, 1-aminocyclopropane-1-carboxylic acid (ACC content and ACC oxidase activities. Pre-treatment with 1-MCP resulted in reduced ethylene production, vase life, ACC content and ACC oxidase activities, but increased bud opening %. Pre-treatment with аquеous ozone failed to influence all those parameters except bud opening %. Interaction effects of hybrid and 1-MCP were significant for ethylene production, hybrid and ozone for vas life, 1-MCP and ozone for bud opening %, and hybrid, 1-MCP and ozone for ethylene production and vase life. Aqueous ozone markedly contributed to the inhibition of microbial growth in vase solution. Pre-treatment of the cut orchid flowers with 300 nL L–11-MCP, followed by using 5.2 mg L–1 aqueous ozone as the vase solution could be recommended to maintain quality and extend vase life of both the DDG and MCJ orchid hybrids.

  1. Microbubble enhanced ozonation process for advanced treatment of wastewater produced in acrylic fiber manufacturing industry

    KAUST Repository

    Zheng, Tianlong; Wang, Qunhui; Zhang, Tao; Shi, Zhining; Tian, Yanli; Shi, Shanshan; Smale, Nicholas; Wang, Juan

    2015-01-01

    zeta potential of the bubbles were also observed in the microbubble ozonation process. The biodegradability of the wastewater was also significantly improved by microbubble-ozonation, which was ascribed to the enhanced degradation of alkanes, aromatic

  2. Ozone-augmented percutaneous discectomy: a novel treatment option for refractory discogenic sciatica.

    Science.gov (United States)

    Crockett, M T; Moynagh, M; Long, N; Kilcoyne, A; Dicker, P; Synnott, K; Eustace, S J

    2014-12-01

    To assess the short and medium-term efficacy and safety of a novel, minimally invasive therapeutic option combining automated percutaneous lumbar discectomy, intradiscal ozone injection, and caudal epidural: ozone-augmented percutaneous discectomy (OPLD). One hundred and forty-seven patients with a clinical and radiological diagnosis of discogenic sciatica who were refractory to initial therapy were included. Fifty patients underwent OPLD whilst 97 underwent a further caudal epidural. Outcomes were evaluated using McNab's score, improvement in visual analogue score (VAS) pain score, and requirement for further intervention. Follow-up occurred at 1 and 6 months, and comparison was made between groups. OPLD achieved successful outcomes in almost three-quarters of patients in the short and medium term. OPLD achieved superior outcomes at 1 and 6 months compared to caudal epidural. There was a reduced requirement for further intervention in the OPLD group. No significant complications occurred in either group. OPLD is a safe and effective treatment for patients with refractory discogenic sciatica in the short and medium term. OPLD has the potential to offer an alternative second-line minimally invasive treatment option that could reduce the requirement for surgery in this patient cohort. Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  3. Using of ozone and UV in the treatment of N'djamena's municipal underground water

    International Nuclear Information System (INIS)

    Mohagir, A. M.; New, M. Tchadanaye; Nanadoum, M.; Tchadanaye, M.; Kapseu, C.; Kamga, R.; Tchiegang, C.; Bup, N. D.

    2008-01-01

    The presence of some epidemics such as cholera typhoid and renal failure were reported frequently in the last 3 years. Since the quality of potable water might be responsible for those diseases. this research work was focused on underground water of N'djamena's municipal on which almost all population of this capital used it as drinking water without purifications samples from 3 different locations were analysed for pH, Ca ++ , Fe ++ , Na + , C1 - , NO 3 - , and SO 4 2- . In addition some microbial analyses before and after treatment were done. Ozone and UV as oxidative and destructive agents were used among the procedure of treatment. The result revealed that filtration process has a significant at P> 0.01 for the removal of total hardness. On the other hand, using of ozone and UV showed a significant difference at P> 0.001 for overcoming the presence of bacteria and aerobic germs. Intensive research works were recommended to minimize the risk that could be associated with drinking water. (author)

  4. Advanced treatment of sodium dithionite wastewater using the combination of coagulation, catalytic ozonation, and SBR.

    Science.gov (United States)

    Zou, Xiao-Ling

    2017-10-01

    A combined process of coagulation-catalytic ozonation-anaerobic sequencing batch reactor (ASBR)-SBR was developed at lab scale for treating a real sodium dithionite wastewater with an initial chemical oxygen demand (COD) of 21,760-22,450 mg/L. Catalytic ozonation with the prepared cerium oxide (CeO 2 )/granular activated carbon catalyst significantly enhances wastewater biodegradability and reduces wastewater microtoxicity. The results show that, under the optimum conditions, the removal efficiencies of COD and suspended solids are averagely 99.3% and 95.6%, respectively, and the quality of final effluent can meet the national discharge standard of China. The coagulation and ASBR processes remove a considerable proportion of organic matter, while the SBR plays an important role in post-polish of final effluent. The ecotoxicity of the wastewater is greatly reduced after undergoing the hybrid treatment. This work demonstrates that the hybrid system has the potential to be applied for the advanced treatment of high-strength industrial wastewater.

  5. Application of Fe(II)/peroxymonosulfate for improving ultrafiltration membrane performance in surface water treatment: Comparison with coagulation and ozonation.

    Science.gov (United States)

    Cheng, Xiaoxiang; Liang, Heng; Ding, An; Zhu, Xuewu; Tang, Xiaobin; Gan, Zhendong; Xing, Jiajian; Wu, Daoji; Li, Guibai

    2017-11-01

    Coagulation and ozonation have been widely used as pretreatments for ultrafiltration (UF) membrane in drinking water treatment. While beneficial, coagulation or ozonation alone is unable to both efficiently control membrane fouling and product water quality in many cases. Thus, in this study an emerging alternative of ferrous iron/peroxymonosulfate (Fe(II)/PMS), which can act as both an oxidant and a coagulant was employed prior to UF for treatment of natural surface water, and compared with conventional coagulation and ozonation. The results showed that the Fe(II)/PMS-UF system exhibited the best performance for dissolved organic carbon removal, likely due to the dual functions of coagulation and oxidation in the single process. The fluorescent and UV-absorbing organic components were more susceptible to ozonation than Fe(II)/PMS treatment. Fe(II)/PMS and ozonation pretreatments significantly increased the removal efficiency of atrazine, p-chloronitrobenzene and sulfamethazine by 12-76% and 50-94%, respectively, whereas coagulation exerted a minor influence. The Fe(II)/PMS pretreatment also showed the best performance for the reduction of both reversible and irreversible membrane fouling, and the performance was hardly affected by membrane pore size and surface hydrophobicity. In addition, the characterization of hydraulic irreversible organic foulants confirmed its effectiveness. These results demonstrate the potential advantages of applying Fe(II)/PMS as a pretreatment for UF to simultaneously control membrane fouling and improve the permeate quality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Partial oxidation of TiN coating by hydrothermal treatment and ozone treatment to improve its osteoconductivity

    International Nuclear Information System (INIS)

    Shi, Xingling; Xu, Lingli; Le, Thi Bang; Zhou, Guanghong; Zheng, Chuanbo; Tsuru, Kanji; Ishikawa, Kunio

    2016-01-01

    Dental implants made of pure titanium suffer from abrasion and scratch during routine oral hygiene procedures. This results in an irreversible surface damage, facilitates bacteria adhesion and increases risk of peri-implantitis. To overcome these problems, titanium nitride (TiN) coating was introduced to increase surface hardness of pure titanium. However, the osteoconductivity of TiN is considered to be similar or superior to that of titanium and its alloys and therefore surface modification is necessary. In this study, TiN coating prepared through gas nitriding was partially oxidized by hydrothermal (HT) treatment and ozone (O 3 ) treatment in pure water to improve its osteoconductivity. The effects of HT treatment and O 3 treatment on surface properties of TiN were investigated and the osteoconductivity after undergoing treatment was assessed in vitro using osteoblast evaluation. The results showed that the critical temperature for HT treatment was 100 °C since higher temperatures would impair the hardness of TiN coating. By contrast, O 3 treatment was more effective in oxidizing TiN surfaces, improving its wettability while preserving its morphology and hardness. Osteoblast attachment, proliferation, alkaline phosphatase (ALP) expression and mineralization were improved on oxidized specimens, especially on O 3 treated specimens, compared with untreated ones. These effects seemed to be consequences of partial oxidation, as well as improved hydrophilicity and surface decontamination. Finally, it was concluded that, partially oxidized TiN is a promising coating to be used for dental implant. - Highlights: • TiN coating surface was oxidized by hydrothermal or ozone treatment while preserving its hardness. • Improved wettability, decontamination and interstitial N promoted osteoblast responses. • Partial oxidation makes TiN a promising coating for dental implant with good osteoconductivity.

  7. Partial oxidation of TiN coating by hydrothermal treatment and ozone treatment to improve its osteoconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Xingling [School of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 (China); Department of Biomaterials, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582 (Japan); Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huaian 223003 (China); Xu, Lingli, E-mail: linly311@163.com [School of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 (China); Le, Thi Bang [Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Zhou, Guanghong [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huaian 223003 (China); Zheng, Chuanbo, E-mail: zjust316@163.com [School of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 (China); Tsuru, Kanji; Ishikawa, Kunio [Department of Biomaterials, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582 (Japan)

    2016-02-01

    Dental implants made of pure titanium suffer from abrasion and scratch during routine oral hygiene procedures. This results in an irreversible surface damage, facilitates bacteria adhesion and increases risk of peri-implantitis. To overcome these problems, titanium nitride (TiN) coating was introduced to increase surface hardness of pure titanium. However, the osteoconductivity of TiN is considered to be similar or superior to that of titanium and its alloys and therefore surface modification is necessary. In this study, TiN coating prepared through gas nitriding was partially oxidized by hydrothermal (HT) treatment and ozone (O{sub 3}) treatment in pure water to improve its osteoconductivity. The effects of HT treatment and O{sub 3} treatment on surface properties of TiN were investigated and the osteoconductivity after undergoing treatment was assessed in vitro using osteoblast evaluation. The results showed that the critical temperature for HT treatment was 100 °C since higher temperatures would impair the hardness of TiN coating. By contrast, O{sub 3} treatment was more effective in oxidizing TiN surfaces, improving its wettability while preserving its morphology and hardness. Osteoblast attachment, proliferation, alkaline phosphatase (ALP) expression and mineralization were improved on oxidized specimens, especially on O{sub 3} treated specimens, compared with untreated ones. These effects seemed to be consequences of partial oxidation, as well as improved hydrophilicity and surface decontamination. Finally, it was concluded that, partially oxidized TiN is a promising coating to be used for dental implant. - Highlights: • TiN coating surface was oxidized by hydrothermal or ozone treatment while preserving its hardness. • Improved wettability, decontamination and interstitial N promoted osteoblast responses. • Partial oxidation makes TiN a promising coating for dental implant with good osteoconductivity.

  8. Cellular attachment and spatial control of cells using micro-patterned ultra-violet/ozone treatment in serum enriched media.

    Science.gov (United States)

    Mitchell, S A; Poulsson, A H C; Davidson, M R; Emmison, N; Shard, A G; Bradley, R H

    2004-08-01

    Ultra-violet Ozone (UVO) modified polystyrene (PS) surfaces were analyzed by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), contact angle (CA), optical microscopy (OM) and cell culture experiments. UV/Ozone treatment up to 900 s was used to increase the surface oxygen concentration of PS surfaces from 0% to approximately 35% (unwashed) and 0% to approximately 27% (washed). The observed differences in oxygen concentration, between washed and unwashed surfaces, have been previously attributed to the removal of low molecular weight debris produced in this treatment process. Surface roughness (Rq) is known to affect cellular attachment and proliferation. AFM studies of the UV/Ozone treated PS surfaces show the surface roughness is an order of magnitude less than that expected to cause an effect. UV/Ozone treatment of PS showed a marked change in CA which decreased to approximately 60 degrees after 900 s treatment. The increased attachment and proliferation of Chinese hamster ovarian (CHO) and mouse embryo 3T3-L1 (3T3) cells on the treated surfaces compared to untreated PS were found to correlate strongly with the increase in surface oxygen concentration. Surface chemical oxidation patterns on the PS were produced using a simple masking technique and a short UV/Ozone treatment time, typically 20-45 s. The chemical patterns on PS were visualized by water condensation and the spatially selective attachment of CHO and 3T3-L1 cells cultured with 10% (v/v) serum. This paper describes an easily reproducible, one step technique to produce a well-defined, chemically heterogeneous surface with a cellular resolution using UV/Ozone modification. By using a variety of cell types, that require different media conditions, we have been able to expand the potential applications of this procedure.

  9. Combination of ozonation, activated carbon, and biological aerated filter for advanced treatment of dyeing wastewater for reuse.

    Science.gov (United States)

    Zou, Xiao-Ling

    2015-06-01

    Laboratorial scale experiments were performed to investigate and evaluate the performance and removal characteristics of organics, color, and genotoxicity by an integrated process including ozonation, activated carbon (AC), and biological aerated filter (BAF) for recycling biotreated dyeing wastewater (BTDW) collected from a cotton textile factory. Influent chemical oxygen demand (COD) in the range of 156 - 252 mg/L, 5-day biochemical oxygen demand (BOD5) of 13.5 - 21.7 mg/L, and color of 58 - 76° were observed during the 20-day continuous operation. Outflows with average COD of 43 mg/L, BOD5 of 6.6 mg/L, and color of 5.6° were obtained after being decontaminated by the hybrid system with ozone dosage of 0.25 mg O3applied/mg COD0, 40 min ozonation contact time, 30 min hydraulic retention time (HRT) for AC treatment, and 2.5 h HRT for BAF treatment. More than 82 % of the genotoxicity of BTDW was eliminated in the ozonation unit. The genotoxicity of the BAF effluent was less than 1.33 μg 4-nitroquinoline-N-oxide/L. Ozonation could change the organics molecular structures, destroy chromophores, increase the biodegradability, and obviously reduce the genotoxicity of BTDW. Results showed that the combined process could guarantee water reuse with high quality.

  10. Method for surface treatment by electron beams

    International Nuclear Information System (INIS)

    Panzer, S.; Doehler, H.; Bartel, R.; Ardenne, T. von.

    1985-01-01

    The invention has been aimed at simplifying the technology and saving energy in modifying surfaces with the aid of electron beams. The described beam-object geometry allows to abandon additional heat treatments. It can be used for surface hardening

  11. Ozonation and H2O2/UV treatment of clofibric acid in water: a kinetic investigation.

    Science.gov (United States)

    Andreozzi, Roberto; Caprio, Vincenzo; Marotta, Raffaele; Radovnikovic, Anita

    2003-10-31

    The presence of pharmaceuticals or their active metabolites in surface and ground waters has been recently reported as mainly due to an incomplete removal of these pollutants in sewage treatment plants (STP). Advanced oxidation processes may represent a suitable tool to reduce environmental release of these species by enhancing the global efficiency of reduction of pharmaceuticals in the municipal sewage plant effluents. The present work aims at assessing the kinetics of abatement from aqueous solutions of clofibric acid (a metabolite of the blood lipid regulator clofibrate) which has been found in surface, ground and drinking waters. Ozonation and hydrogen peroxide photolysis are capable of fast removal of this species in aqueous solution, with an almost complete conversion of the organic chlorine content into chloride ions for the investigated reaction conditions. A validation of assessed kinetics at clofibric acid concentrations as low as those found in STP effluents is presented for both systems.

  12. Recolonization by heterotrophic bacteria after UV irradiation or ozonation of seawater; a simulation of ballast water treatment.

    Science.gov (United States)

    Hess-Erga, Ole-Kristian; Blomvågnes-Bakke, Bente; Vadstein, Olav

    2010-10-01

    Transport of ballast water with ships represents a risk for introduction of foreign species. If ballast water is treated during uptake, there will be a recolonization of the ballast water by heterotrophic bacteria during transport. We investigated survival and succession of heterotrophic bacteria after disinfection of seawater in the laboratory, representing a model system of ballast water treatment and transport. The seawater was exposed to ultraviolet (UV) irradiation, ozone (2 doses) or no treatment, incubated for 16 days and examined with culture-dependent and -independent methods. The number of colony-forming units (CFU) was reduced below the detection level after disinfection with UV and high ozone dose (700 mV), and 1% of the initial level for the low ozone dose (400 mV). After less than 3 days, the CFU was back or above the starting point for the control, UV and low ozone treatment, whereas it took slightly more than 6 days for the high ozone treatment. Disinfection increased substrate availability and reduced cell densities. Lack of competition and predation induced the recolonization by opportunistic bacteria (r-strategists), with significant increase in bacterial numbers and a low diversity (based on DGGE band pattern). All cultures stabilized after the initial recolonization phase (except Oz700) where competition due to crowding and nutrient limitation favoured bacteria with high substrate affinity (K-strategists), resulting in higher species richness and diversity (based on DGGE band pattern). The bacterial community was significantly altered qualitatively and quantitatively and may have a higher potential as invaders in the recipient depending on disinfection method and the time of release. These results have implications for the treatment strategy used for ballast water. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Effects of UV irradiation on humic acid removal by ozonation, Fenton and Fe0/air treatment: THMFP and biotoxicity evaluation

    International Nuclear Information System (INIS)

    Wei, Ming-Chi; Wang, Kai-sung; Hsiao, Tung-En; Lin, I.-Chen; Wu, Hui-Ju; Wu, Yuh-Luan; Liu, Pey-Horng; Chang, Shih-Hsien

    2011-01-01

    Highlights: → Fe 0 /air rapidly and effectively removed HA within 9 min and its COD, biotoxicity and THMFP were low. → THMFP of ozonation-treated solution was much higher than those of Fenton-treated and Fe 0 /air-treated solutions. → UV irradiation during ozonation and Fenton oxidation enhanced HA removal, but did not reduce the THMFP of the treated solutions. → Fe 0 /air treatment with UV irradiation obviously increased the THMFP of the treated solution. → The relationship between biotoxicity and chloroform in the chlorinated solution was insignificant. - Abstract: Effects of UV irradiation on humic acid (HA) removal by Fe 0 /air, ozonation and Fenton oxidation were investigated. The trihalomethane forming potential (THMFP) and toxicity of treated solutions were also evaluated. The experimental conditions were ozone of 21 mg min -1 , H 2 O 2 of 8 x 10 -4 M, Fe 0 of 20 g L -1 , air flow of 5 L min -1 , and UVC of 9 W. Results indicated that Fe 0 /air rapidly removed HA color (>99%) and COD (90%) within 9 min. 51-81% of color and 43-50% of COD were removed by ozonation and Fenton oxidation after 60 min. Both UV enhanced ozone and Fenton oxidation removed HA, but the Fe 0 /air process did not. Spectrum results showed all processes effectively diminished UV-vis spectra, except for ozonation. The THMFP of Fe 0 /air-treated solution (114 μg L -1 ) was much lower than those of Fenton- (226 μg L -1 ) and ozonation-treated solutions (499 μg L -1 ). Fe 0 /air with UV irradiation obviously increased the THMFP of treated solution (502 μg L -1 ). The toxicity results obtained from Vibrio fischeri light inhibition test indicated that the toxicity of Fe 0 /air-treated solution (5%) was much lower than that of ozonation- (33%) and Fenton-treated solutions (31%). Chlorination increased the solution toxicity. The correlation between biotoxicity and chloroform in the chlorinated solution was insignificant.

  14. Controlling Nitrosamines, Nitramines, and Amines in Amine-Based CO₂ Capture Systems with Continuous Ultraviolet and Ozone Treatment of Washwater.

    Science.gov (United States)

    Dai, Ning; Mitch, William A

    2015-07-21

    Formation of nitrosamines and nitramines from reactions between flue gas NOx and the amines used in CO2 capture units has arisen as a significant concern. Washwater scrubbers can capture nitrosamines and nitramines. They can also capture amines, preventing formation of nitrosamines and nitramines downwind by amine reactions with ambient NOx. The continuous application of UV alone, or a combination of UV and ozone to the return line of a washwater treatment unit was evaluated to control the accumulation of nitrosamines, nitramines and amines in a laboratory-scale washwater unit. With model secondary amine solvents ranging from nonvolatile diethanolamine to volatile morpholine, application of 272-537 mJ/cm(2) UV incident fluence alone reduced the accumulation of nitrosamines and nitramines by approximately an order of magnitude. Modeling indicated that the gains achieved by UV treatment should increase over time, because UV treatment converts the time dependence of nitrosamine accumulation from a quadratic to a linear function. Ozone (21 mg/L) maintained low steady-state concentrations of amines in the washwater. While modeling indicated that more than 80% of nitrosamine accumulation in the washwater was associated with reaction of washwater amines with residual NOx, a reduction in nitrosamine accumulation rates due to ozone oxidation of amines was not fully realized because the ozonation products of amines reduced nitrosamine photolysis rates by competing for photons.

  15. Comparing removal efficiency and reaction rates of organic micro-pollutants during ozonation from different municipal waste water treatment plants effluents in Sweden

    DEFF Research Database (Denmark)

    El-taliawy, Haitham; Ekblad, Maja; Nilsson, Filip

    2015-01-01

    The Removal of about 50 micro-pollutants from 7 waste water treatment plant effluents –in Sweden- was tested on pilot scale. Different ozone doses and two different pilots with different reactor sizes and retention times were tested. Ozone reaction rates depended on DOC concentration in the water...

  16. Total electron count variability and stratospheric ozone effects on solar backscatter and LWIR emissions

    Science.gov (United States)

    2017-03-10

    heating occur. This method is achieved though measuring the intensity ratio of sky- scattered sunlight at a pair of UV wavelengths at solar zenith angles...cause impacts to direct-sun, UV, and zenith measurements . OOB light can affect the low intensity spectrum of solar light, which is not fully removed by...several key spectral properties that are pertinent to its measurement . Ozone is greenhouse gas that plays a primary role in the absorption of solar UV

  17. Effects of ozone as a stand-alone and coagulation-aid treatment on the reduction of trihalomethanes precursors from high DOC and hardness water.

    Science.gov (United States)

    Sadrnourmohamadi, Mehrnaz; Gorczyca, Beata

    2015-04-15

    This study investigates the effect of ozone as a stand-alone and coagulation aid on the removal of dissolved organic carbon (DOC) from the water with a high level of DOC (13.8 mgL(-1)) and calcium hardness (270 mgL(-1)) CaCO3. Natural water collected from the Assiniboine River (Manitoba, Canada) was used in this study. Effectiveness of ozone treatment was evaluated by measurement of DOC, DOC fractions, UV254, and trihalomethane formation potential (THMFP). Additionally, zeta potential and dissolved calcium concentration were measured to discern the mechanism of ozone reactions. Results indicated that 0.8 mg O3/mg DOC ozone stand-alone can cause up to 86% UV254 reduction and up to 27% DOC reduction. DOC fractionation results showed that ozone can change the composition of DOC in the water samples, converting the hydrophobic fractions into hydrophilic ones and resulting in the reduction of THMFP. Also, ozone caused a decrease in particle stability and dissolved calcium concentration. These simultaneous ozonation effects caused improved water flocculation and enhanced removal of DOC. This resulted in reduction of the coagulant dosage when ozone doses higher than 0.2 mg O3/mg DOC were applied prior to coagulation with ferric sulfate. Also, pre-ozonation-coagulation process achieved preferential THMFP removal for all of the ozone doses tested (0-0.8 mg O3/mg DOC), leading to a lower specific THMFP in pre-ozonated-coagulated waters than in the corresponding ozonated waters. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Cyanide Containing Wastewater Treatment by Ozone Enhanced Catalytic Oxidation over Diatomite Catalysts

    Directory of Open Access Journals (Sweden)

    Lin Mingguo

    2018-01-01

    Full Text Available Cyanide containing wastewater that discharged from gold mining process creates environmental problems due to the toxicity of cyanide. As one of the promising advanced oxidation process, catalytic oxidation with ozone is considered to be effective on the purification of cyanide. Diatomite, a natural mineral, was used as catalyst in this study. The effect of O3 dosage, salinity, initial cyanide concentration and initial pH condition were investigated. It was observed that the removal rate of cyanide was much higher in the catalytic oxidation with ozone process than the one in zone alone process. Alkaline condition was especially favorable for cyanide in catalytic oxidation with ozone. The ozone and catalytic oxidation with ozone were simulated by pseudo-first-order kinetics model. The apparent first-order rate constant contribution of the diatomite catalyst was 0.0757 min-1, and the contribution percentage was 65.77%.

  19. Efficiency enhancement of silicon nanowire solar cells by using UV/Ozone treatments and micro-grid electrodes

    Science.gov (United States)

    Chen, Junyi; Subramani, Thiyagu; Sun, Yonglie; Jevasuwan, Wipakorn; Fukata, Naoki

    2018-05-01

    Silicon nanowire solar cells were fabricated by metal catalyzed electroless etching (MCEE) followed by thermal chemical vapor deposition (CVD). In this study, we investigated two effects, a UV/ozone treatment and the use of a micro-grid electrodes, to enhance light absorption and reduce the optic losses in the solar cell device. The UV/ozone treatment successfully improved the conversion efficiency. The micro-grid electrodes were then applied in solar cell devices subjected to a back surface field (BSF) treatment and rapid thermal annealing (RTA). These effects improved the conversion efficiency from 9.4% to 10.9%. Moreover, to reduce surface recombination and improve the continuity of front electrodes, we optimized the etching time of the MCEE process, giving a high efficiency of 12.3%.

  20. Kansas City plant ultraviolet/ozone/hydrogen peroxide groundwater treatment system overview

    International Nuclear Information System (INIS)

    Stites, M.E.; Hughes, R.F.

    1992-01-01

    The Kansas City Plant (KCP) has committed to the utilization of a groundwater treatment system, for removal of volatile organic compounds (VOCs), that discharges a minimal amount of pollutants to the environment. An advanced oxidation process (AOP) system utilizing ozone, ultraviolet radiation, and hydrogen peroxide serves in this capacity. Packed tower aeration and activated carbon filtration are listed as best available technologies (BATs) by the Environmental Protection Agency (EPA) for the removal of VOCs in water. The disadvantage to these BATs is that they transfer the VOCs from the water medium to the air or carbon media respectively. Operation of the system began in May 1988 at a flow rate of 22.7 liters per minute (lpm) (6 gallons per minute (gpm)). An additional 102.2 lpm (27 gpm) of flow were added in October 1990. Various efforts to optimize and track the treatment unites efficiency have been carried out. A maximum influent reading of 26,590 parts per billion (ppb) of total VOCs has been recorded. Following the addition of flows, removal efficiency has averaged approximately 95%. Both air and water effluents are factored into this calculation. (author)

  1. The use of ozone to during water treatment; El uso de ozono en estaciones de tratamiento de agua potable (ETAP)

    Energy Technology Data Exchange (ETDEWEB)

    Quiros Sanchez, E.; Herraez Sanchez de las Matas, I.

    2004-07-01

    Water is rendered drinkable by using disinfecting methods like chlorination, ozonization or ultraviolet radiation, thus ensuring that pathogens are kept at the correct safety level. Of the three methods for disinfecting, chlorination is by far the method most frequently used. Despite the former, there has been a change in technology in favour of ozone and to the detriment of chlorine. This trend was motivated, in the first place, by European Union legislation adopted by the Spanish legal system in February 2003, which limits the presence of certain compounds such as tri halomethanes (THM) to levels that can only be attained if we apply ozone. As far as an alternative to chlorine in the disinfecting process is concerned, it cannot be claimed that a clear solution has been found because it is the only one having a residual effect acting as a guarantee for the entree distribution network. According to these experimental data from the drinking water plant of Santillana, by applying an ozonization system prior to chlorination the quantity of chlorine used can be reduced by about 25-30%, but it can never be totally eliminated from the treatment. (Author)

  2. A hybrid treatment of ozonation with limestone adsorption processes for the removal of Fe2+ in groundwater: Fixed bed column study

    Science.gov (United States)

    Akbar, Nor Azliza; Aziz, Hamidi Abdul; Adlan, Mohd Nordin

    2017-10-01

    During pumping of groundwater to the surface, the reaction between dissolved iron (Fe2+) and oxygen causes oxidation to ferric iron (Fe3+), thereby increasing the concentration of Fe2+. In this research, the potential application of ozonation with limestone adsorption to remove Fe2+ from groundwater was investigated through batch ozonation and fixed-bed-column studies. Groundwater samples were collected from a University Science Malaysia tube well (initial concentration of Fe2+, Co=1.563 mg/L). The effect of varying ozone dosages (10, 12.5, 15, 17.5, 20, 22.5, and 25 g/Nm3) was analyzed to determine the optimum ozone dosage for treatment. The characteristics of the column data and breakthrough curve were analyzed and predicted using mathematical models, such as Adam Bohart, Thomas, and Yoon-Nelson models. The data fitted well to the Thomas and Yoon-Nelson models, with correlation coefficient r2>0.93, but not to the Adam Bohart (r2=0.47). The total Fe2+ removed was 72% (final concentration of Fe2+, Ct=0.426 mg/L) at the maximum dosage of 25 g/Nm3 through ozonation only. However, the efficiency of Fe2+ removal was increased up to 99.5% (Ct=0.008 mg/L) when the hybrid treatment of ozonation with limestone adsorption was applied in this study. Thus, this integrated treatment was considerably more effective in removing Fe2+ than single ozonation treatment.

  3. Statistical evaluation of mature landfill leachate treatment by homogeneous catalytic ozonation

    Directory of Open Access Journals (Sweden)

    A. L. C. Peixoto

    2010-12-01

    Full Text Available This study presents the results of a mature landfill leachate treated by a homogeneous catalytic ozonation process with ions Fe2+ and Fe3+ at acidic pH. Quality assessments were performed using Taguchi's method (L8 design. Strong synergism was observed statistically between molecular ozone and ferric ions, pointing to their catalytic effect on •OH generation. The achievement of better organic matter depollution rates requires an ozone flow of 5 L h-1 (590 mg h-1 O3 and a ferric ion concentration of 5 mg L-1.

  4. Electron beam flue gas treatment process. Review

    International Nuclear Information System (INIS)

    Honkonen, V.A.

    1996-01-01

    The basis of the process for electron beam flue gas treatment are presented in the report. In tabular form the history of the research is reviewed. Main dependences of SO 2 and NO x removal efficiencies on different physico-chemical parameters are discussed. Trends concerning industrial process implementation are presented in the paper,finally. (author). 74 refs, 11 figs, 1 tab

  5. Domestic wastewater treatment using electron accelerator

    International Nuclear Information System (INIS)

    Borrely, Sueli I.

    1995-01-01

    This work aims the application of an industrial electron beam accelerator to disinfect sludge and to remove organic matter existent in the influent and effluent from the Mairipora domestic wastewater treatment plant. The in vitro Co-60 radiosensitivity of the major representative Salmonella species in wastewater from Sao Paulo city was also studied. (author). 66 refs., 19 figs., 12 tabs

  6. A simple UV-ozone surface treatment to enhance photocatalytic performance of TiO 2 loaded polymer nanofiber membranes

    KAUST Repository

    Dilpazir, S.

    2016-01-29

    Homogeneously dispersed titanium dioxide loaded polyacrylonitrile nanofiber membranes with increased active mass loading, Ti3+ surface defects and hydrophilicity were fabricated by combining electrospinning and UV-ozone surface treatment. The photocatalytic activity improved by a factor of ∼2 and the kinetics of photodegradation switched from pseudo-first order to pseudo-second order with increasing TiO2 content with a maximum rate constant of 20.7 h-1. © The Royal Society of Chemistry 2016.

  7. Exhaust gas treatment by electron beam irradiation

    International Nuclear Information System (INIS)

    Shibamura, Yokichi; Suda, Shoichi; Kobayashi, Toshiki

    1991-01-01

    Among global environmental problems, atmospheric pollution has been discussed since relatively old days, and various countermeasures have been taken, but recently in connection with acid rain, the efficient and economical treatment technology is demanded. As the denitration and desulfurization technology for the exhaust gas from the combustion of fossil fuel, the incineration of city trash and internal combustion engines, three is the treatment method by electron beam irradiation. By irradiating electron beam to exhaust gas, nitrogen oxides and sulfur oxides are oxidized to nitric acid and sulfuric acid, and by promoting the neutralization of these acids with injected alkali, harmless salts are recovered. This method has the merit that nitrogen oxides and surfur oxides can be removed efficiently with a single system. In this report, as for the exhaust gas treatment by electron beam irradiation, its principle, features, and the present status of research and development are described, and in particular, the research on the recent exhaust gas treatment in city trash incineration is introduced. This treatment method is a dry process, accordingly, waste water disposal is unnecessary. The reaction products are utilized as fertilizer, and waste is not produced. (K.I.)

  8. Insights into the Electronic Structure of Ozone and Sulfur Dioxide from Generalized Valence Bond Theory: Addition of Hydrogen Atoms.

    Science.gov (United States)

    Lindquist, Beth A; Takeshita, Tyler Y; Dunning, Thom H

    2016-05-05

    Ozone (O3) and sulfur dioxide (SO2) are valence isoelectronic species, yet their properties and reactivities differ dramatically. In particular, O3 is highly reactive, whereas SO2 is chemically relatively stable. In this paper, we investigate serial addition of hydrogen atoms to both the terminal atoms of O3 and SO2 and to the central atom of these species. It is well-known that the terminal atoms of O3 are much more amenable to bond formation than those of SO2. We show that the differences in the electronic structure of the π systems in the parent triatomic species account for the differences in the addition of hydrogen atoms to the terminal atoms of O3 and SO2. Further, we find that the π system in SO2, which is a recoupled pair bond dyad, facilitates the addition of hydrogen atoms to the sulfur atom, resulting in stable HSO2 and H2SO2 species.

  9. Enhanced treatment of secondary municipal wastewater effluent: comparing (biological) filtration and ozonation in view of micropollutant removal, unselective effluent toxicity, and the potential for real-time control.

    Science.gov (United States)

    Chys, Michael; Demeestere, Kristof; Ingabire, Ange Sabine; Dries, Jan; Van Langenhove, Herman; Van Hulle, Stijn W H

    2017-07-01

    Ozonation and three (biological) filtration techniques (trickling filtration (TF), slow sand filtration (SSF) and biological activated carbon (BAC) filtration) have been evaluated in different combinations as tertiary treatment for municipal wastewater effluent. The removal of 18 multi-class pharmaceuticals, as model trace organic contaminants (TrOCs), has been studied. (Biological) activated carbon filtration could reduce the amount of TrOCs significantly (>99%) but is cost-intensive for full-scale applications. Filtration techniques mainly depending on biodegradation mechanisms (TF and SSF) are found to be inefficient for TrOCs removal as a stand alone technique. Ozonation resulted in 90% removal of the total amount of quantified TrOCs, but a post-ozonation step is needed to cope with an increased unselective toxicity. SSF following ozonation showed to be the only technique able to reduce the unselective toxicity to the same level as before ozonation. In view of process control, innovative correlation models developed for the monitoring and control of TrOC removal during ozonation, are verified for their applicability during ozonation in combination with TF, SSF or BAC. Particularly for the poorly ozone reactive TrOCs, statistically significant models were obtained that correlate TrOC removal and reduction in UVA 254 as an online measured surrogate parameter.

  10. Monitoring the biological activity of micropollutants during advanced wastewater treatment with ozonation and activated carbon filtration.

    Science.gov (United States)

    Macova, M; Escher, B I; Reungoat, J; Carswell, S; Chue, K Lee; Keller, J; Mueller, J F

    2010-01-01

    initial steps of the treatment chain, no significant degradation of micropollutants was observed, and the high levels of dissolved organic carbon probably affected the outcome of the bioassays. The steps of coagulation/flocculation/dissolved air flotation/sand filtration and ozonation decreased the effect-based micropollutant burden significantly. (c) 2009 Elsevier Ltd. All rights reserved.

  11. Impact of ozonation, anion exchange resin and UV/H2O2 pre-treatments to control fouling of ultrafiltration membrane for drinking water treatment.

    Science.gov (United States)

    Pramanik, Biplob Kumar; Pramanik, Sagor Kumar; Sarker, Dipok Chandra; Suja, Fatihah

    2017-06-01

    The effects of ozonation, anion exchange resin (AER) and UV/H 2 O 2 were investigated as a pre-treatment to control organic fouling (OF) of ultrafiltration membrane in the treatment of drinking water. It was found that high molecular weight (MW) organics such as protein and polysaccharide substances were majorly responsible for reversible fouling which contributed to 90% of total fouling. The decline rate increased with successive filtration cycles due to deposition of protein content over time. All pre-treatment could reduce the foulants of a Ultrafiltration membrane which contributed to the improvement in flux, and there was a greater improvement of flux by UV/H 2 O 2 (61%) than ozonation (43%) which in turn was greater than AER (23%) treatment. This was likely due to the effective removal/breakdown of high MW organic content. AER gave greater removal of biofouling potential components (such as biodegradable dissolved organic carbon and assimilable organic carbon contents) compared to UV/H 2 O 2 and ozonation treatment. Overall, this study demonstrated the potential of pre-treatments for reducing OF of ultrafiltration for the treatment of drinking water.

  12. Treatment of aqueous wastes contaminated with Congo Red dye by electrochemical oxidation and ozonation processes

    International Nuclear Information System (INIS)

    Faouzi Elahmadi, Mohammed; Bensalah, Nasr; Gadri, Abdellatif

    2009-01-01

    Synthetic aqueous wastes polluted with Congo Red (CR) have been treated by two advanced oxidation processes: electrochemical oxidation on boron doped diamond anodes (BDD-EO) and ozonation under alkaline conditions. For same concentrations, galvanostatic electrolyses have led to total COD and TOC removals but ozonation process can reach only 85% and 81% of COD and TOC removals, respectively. UV-vis qualitative analyses have shown different behaviors of CR molecules towards ozonation and electrochemical oxidation. Rapid discoloration has been observed during ozonation, whereas color persistence till the end of galvanostatic electrolyses has been seen during BDD-EO process. It seems that the oxidation mechanisms involved in the two processes are different: simultaneous destruction of azoic groups is suggested during ozonation process but consecutive destruction of these groups is proposed during BDD-EO. However, energetic study has evidenced that BDD-EO appears more efficient and more economic than ozonation in terms of TOC removals. These results have been explained by the fact that during BDD-EO, other strong oxidants electrogenerated from the electrolyte oxidation such as persulfates and direct-oxidation of CR and its byproducts on BDD anodes complement the hydroxyl radicals mediated oxidation to accomplish the total mineralization of organics.

  13. Electron Density Calibration for Radiotherapy Treatment Planning

    International Nuclear Information System (INIS)

    Herrera-Martinez, F.; Rodriguez-Villafuerte, M.; Martinez-Davalos, A.; Ruiz-Trejo, C.; Celis-Lopez, M. A.; Larraga-Gutierrez, J. M.; Garcia-Garduno, A.

    2006-01-01

    Computed tomography (CT) images are used as basic input data for most modern radiosurgery treatment planning systems (TPS). CT data not only provide anatomic information to delineate target volumes, but also allow the introduction of corrections for tissue inhomogeneities into dose calculations during the treatment planning procedure. These corrections involve the determination of a relationship between tissue electron density (ρe) and their corresponding Hounsfield Units (HU). In this work, an elemental analysis of different commercial tissue equivalent materials using Scanning Electron Microscopy was carried out to characterize their chemical composition. The tissue equivalent materials were chosen to ensure a large range of ρe to be included in the CT scanner calibration. A phantom was designed and constructed with these materials to simulate the size of a human head

  14. Comparison of coagulation, ozone and ferrate treatment processes for color, COD and toxicity removal from complex textile wastewater.

    Science.gov (United States)

    Malik, Sameena N; Ghosh, Prakash C; Vaidya, Atul N; Waindeskar, Vishal; Das, Sera; Mudliar, Sandeep N

    2017-09-01

    In this study, the comparative performance of coagulation, ozone, coagulation + ozone + coagulation and potassium ferrate processes to remove chemical oxygen demand (COD), color, and toxicity from a highly polluted textile wastewater were evaluated. Experimental results showed that ferrate alone had no effect on COD, color and toxicity removal. Whereas, in combination with FeSO 4 , it has shown the highest removal efficiency of 96.5%, 83% and 75% for respective parameters at the optimal dose of 40 mgL -1 + 3 ml FeSO 4 (1 M) in comparison with other processes. A seed germination test using seeds of Spinach (Spinacia oleracea) also indicated that ferrate was more effective in removing toxicity from contaminated textile wastewater. Potassium ferrate also produces less sludge with maximum contaminant removal, thereby making the process more economically feasible. Fourier transform infrared spectroscopy (FTIR) analysis also shows the cleavage of the chromophore group and degradation of textile wastewater during chemical and oxidation treatment processes.

  15. [Ozone therapy and phototherapy with polarized polychromatic light in treatment of patients suffering from lower limb critical ischaemia].

    Science.gov (United States)

    Drozhzhin, E V; Sidorkina, O N

    2012-01-01

    The authors generalized their experience in treating a total of 77 patients presenting with atherosclerosis of the arteries of lower limbs with degree III-IV ischaemia according to the A.V. Pokrovsky-Fontain classification. The patients were subjected to comprehensive treatment including the impact of piler-light (apparatus Bioptron 2) and ozone therapy. The control group was composed of 66 people receiving conventional therapy. The two groups were comparable by the nosological entity of the disease, gender, age, and the nature of accompanying pathology. Despite carried out classical anticoagulation therapy there was a tendency towards hypercoagulation in phase I (formation of prothrombinase) and phase III (formation of fibrin) of plasma haemostasis, as well as insufficiency of the fibrinolytic system. The obtained results showed direct influence of ozone therapy and piler light on phase I and III plasmatic haemostasis, as well as enhanced fibrinolytic activity of blood on the background of their administration thereof.

  16. Auger Electron Therapy And Brachytherapy Tumor Treatment

    International Nuclear Information System (INIS)

    Laster, B.H.; Shani, G.

    2002-01-01

    Auger Electron Therapy (AET) is a binary approach for improving cancer radiotherapy. It involves the selective targeting of an atom to tumor cells using physiological pathway. The atom is then irradiated by a specific radiation that produces secondary radiation called Auger electrons. One of the problems associated with the clinical application of AET, is that the energy of the photons required for stimulating photoelectric absorption in most of the available high Z target atoms, is too low to achieve penetration through normal surrounding tissues to the depth of the tumor, when an external source is used. The solution is therefore the use of a brachytherapy technique. There are two other problems associated with the use of radiation as a cancer treatment. The first is the limitation on radiation dose to the normal tissue within the treatment volume. The second problem is the limitation imposed by the miniscule size of the critical target of the cell, namely the DNA (0.25% of the cell mass). The solution to the first problem can be achieved by using the brachytherapy technique. The second problem can be resolved by placing the radiation source in close position to the DNA. AET, as we apply it, provides the two solutions to the two problems. When a photon is absorbed by an electron in the K or L shell of an high Z atom, the electron is ejected from the atom, creating a vacancy in the shell. This vacancy is immediately filled with an electron from an upper shell. The energy difference between the two shells is sometimes emitted as an x-ray, however, frequently the energy is transferred to an outer shell electron that is emitted as an Auger electron. These electrons are emitted at energies of up to ∼30 keV and therefore have a very short range in the cell. They will deposit all their energy within 20-30 nm from the point of emission. i.e. all the energy is deposited in the DNA. In our work indium is used as the high Z atom

  17. Computed tomography-guided percutaneous ozone injection of the Gasserian ganglion for the treatment of trigeminal neuralgia

    Directory of Open Access Journals (Sweden)

    An JX

    2018-01-01

    2.18 in group A and 2.86 ± 1.46 in group B, a decrease compared to pretreatment (P < 0.05. VAS of Group A and B showed no difference not only in pretreatment but also in postreatment and follow-up. Conclusion: Percutaneous ozone injection is a safe and effective treatment for patients with refractory trigeminal neuralgia. Keywords: trigeminal neuralgia, percutaneous ozone injection, Gasserian ganglion

  18. Choice of intra-articular injection in treatment of knee osteoarthritis: platelet-rich plasma, hyaluronic acid or ozone options.

    Science.gov (United States)

    Duymus, Tahir Mutlu; Mutlu, Serhat; Dernek, Bahar; Komur, Baran; Aydogmus, Suavi; Kesiktas, Fatma Nur

    2017-02-01

    This study was performed to compare the efficacy of treatment in three groups of patients with knee osteoarthritis (OA) given an intra-articular injection of platelet-rich plasma (PRP), hyaluronic acid (HA) or ozone gas. A total of 102 patients with mild-moderate and moderate knee OA who presented at the polyclinic with at least a 1-year history of knee pain and VAS score ≥4 were randomly separated into three groups. Group 1 (PRP group) received intra-articular injection of PRP × 2 doses, Group 2 (HA group) received a single dose of HA, and Group 3 (Ozone group) received ozone × four doses. Weight-bearing anteroposterior-lateral and Merchant's radiographs of both knees were evaluated. WOMAC and VAS scores were applied to all patients on first presentation and at 1, 3, 6 and 12 months. At the end of the 1st month after injection, significant improvements were seen in all groups. In the 3rd month, the improvements in WOMAC and VAS scores were similar in Groups 1 and 2, while those in Group 3 were lower (p injections, as the application alone was sufficient to provide at least 12 months of pain-free daily living activities. Therapeutic study, Level I.

  19. Electron beam treatment of wastewaters and sludges

    International Nuclear Information System (INIS)

    Osborn, D.W.

    1980-01-01

    Various procedures for decreasing the health risks associated with the disposal of sewage sludges are discussed including land storage, thermophilic digestion, autothermal aerobic digestion, the Porteus Process, the Zimpro Process, incineration, pyrolysis, thermal pasteurisation, composting, lime utilisation, flash drying and radiation techniques. A fully automated sludge irradiation facility at Geiselbullach near Munich and an electron accelerator experimental plant near Boston are described. Advantages and disadvantages are given for both processes. Costs of electron radiation treatment of sewage sludges (a slurry containing 5 per cent solids) for a city the size of Johannesburg is estimated to be in the order of R900 000 per year at a dose rate of 4 000 Gy, which would produce a product of reasonable hygienic quality but not necessarily meet the criteria laid down by local authority medical officers at all times. In order to reduce costs it would be necessary to have a readily available market to dispose of disinfected material

  20. Electron beam treatment of wastewaters and sludges

    Energy Technology Data Exchange (ETDEWEB)

    Osborn, D W [City Health Dept., Johannesburg (South Africa)

    1980-12-01

    Various procedures for decreasing the health risks associated with the disposal of sewage sludges are discussed including land storage, thermophilic digestion, autothermal aerobic digestion, the Porteus Process, the Zimpro Process, incineration, pyrolysis, thermal pasteurisation, composting, lime utilisation, flash drying and radiation techniques. A fully automated sludge irradiation facility at Geiselbullach near Munich and an electron accelerator experimental plant near Boston are described. Advantages and disadvantages are given for both processes. Costs of electron radiation treatment of sewage sludges (a slurry containing 5 per cent solids) for a city the size of Johannesburg is estimated to be in the order of R900,000 per year at a dose rate of 4,000 Gy, which would produce a product of reasonable hygienic quality but not necessarily meet the criteria laid down by local authority medical officers at all times. In order to reduce costs it would be necessary to have a readily available market to dispose of disinfected material.

  1. Effects of Acute Ozone Exposure and Methyl Jasmonate Treatment on White Pine Monoterpene and Sesquiterpene Emission Rates

    Science.gov (United States)

    Faiola, C. L.; Wagner, D.; Allwine, E.; Harley, P. C.; Vanreken, T. M.

    2010-12-01

    Biogenic volatile organic compounds (BVOCs) are produced by plants and include monoterpenes, sesquiterpenes, and their oxygenated derivatives. These BVOCs are one of the principal factors influencing the oxidative capacity of the atmosphere in forested regions, and impact both ozone concentration and secondary organic aerosol formation. Under unstressed conditions, the release of BVOCs to the atmosphere is primarily controlled by the vapor pressure of the relevant compounds within the plant tissue, which is in turn dependent on temperature as well as complex biochemical production processes. However, various natural and anthropogenic stressors can alter both the quantity and composition of the BVOCs emitted by plants. Many potential stressors are expected to become stronger as climate change effects escalate. The impacts of most stressors on BVOC emissions have not been well characterized, particularly in a field setting where changes in BVOC emissions could have influential feedbacks with climate. This study investigated the effects of two stressors on monoterpene and sesquiterpene emission rates at a field site in northern Michigan: acute ozone exposure and treatment with methyl jasmonate, an herbivory proxy. The study included six repetitions of the same experiment, each time using a new set of sub-canopy eastern white pine specimens. For each experiment, dynamic branch enclosures were simultaneously used on three specimens for sample collection: one ozone treatment tree, one methyl jasmonate treatment tree, and one control tree. Sampling lines were placed in each enclosure and VOCs were collected onto cartridges packed with Tenax GR adsorbent. Samples were collected several times per day for at least two days before treatment and for five days after treatment. Cartridges were analyzed via thermodesorption with an Agilent GC/MS/FID. This analysis allowed the identification and quantification of several monoterpene and sesquiterpene species in the samples

  2. Life cycle assessment of electronic waste treatment.

    Science.gov (United States)

    Hong, Jinglan; Shi, Wenxiao; Wang, Yutao; Chen, Wei; Li, Xiangzhi

    2015-04-01

    Life cycle assessment was conducted to estimate the environmental impact of electronic waste (e-waste) treatment. E-waste recycling with an end-life disposal scenario is environmentally beneficial because of the low environmental burden generated from human toxicity, terrestrial ecotoxicity, freshwater ecotoxicity, and marine ecotoxicity categories. Landfill and incineration technologies have a lower and higher environmental burden than the e-waste recycling with an end-life disposal scenario, respectively. The key factors in reducing the overall environmental impact of e-waste recycling are optimizing energy consumption efficiency, reducing wastewater and solid waste effluent, increasing proper e-waste treatment amount, avoiding e-waste disposal to landfill and incineration sites, and clearly defining the duties of all stakeholders (e.g., manufacturers, retailers, recycling companies, and consumers). Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Ozone oxidation of antidepressants in wastewater –Treatment evaluation and characterization of new by-products by LC-QToFMS

    Directory of Open Access Journals (Sweden)

    Lajeunesse André

    2013-01-01

    Full Text Available Abstract Background The fate of 14 antidepressants along with their respective N-desmethyl metabolites and the anticonvulsive drug carbamazepine was examined in a primary sewage treatment plant (STP and following advanced treatments with ozone (O3. The concentrations of each pharmaceutical compound were determined in raw sewage, effluent and sewage sludge samples by LC-MS/MS analysis. The occurrence of antidepressant by-products formed in treated effluent after ozonation was also investigated. Results Current primary treatments using physical and chemical processes removed little of the compounds (mean removal efficiency: 19%. Experimental sorption coefficients (Kd of each studied compounds were also calculated. Sorption of venlafaxine, desmethylvenlafaxine, and carbamazepine on sludge was assumed to be negligible (log Kd ≤ 2, but higher sorption behavior can be expected for sertraline (log Kd ≥ 4. Ozonation treatment with O3 (5 mg/L led to a satisfactory mean removal efficiency of 88% of the compounds. Screening of the final ozone-treated effluent samples by high resolution-mass spectrometry (LC-QqToFMS did confirm the presence of related N-oxide by-products. Conclusion Effluent ozonation led to higher mean removal efficiencies than current primary treatment, and therefore represented a promising strategy for the elimination of antidepressants in urban wastewaters. However, the use of O3 produced by-products with unknown toxicity.

  4. Life cycle assessment of electronic waste treatment

    International Nuclear Information System (INIS)

    Hong, Jinglan; Shi, Wenxiao; Wang, Yutao; Chen, Wei; Li, Xiangzhi

    2015-01-01

    Highlights: • Life cycle assessment of electronic waste recycling is quantified. • Key factors for reducing the overall environmental impact are indentified. • End-life disposal processes provide significant environmental benefits. • Efficiently reduce the improper disposal amount of e-waste is highly needed. • E-waste incineration can generate significant environmental burden. - Abstract: Life cycle assessment was conducted to estimate the environmental impact of electronic waste (e-waste) treatment. E-waste recycling with an end-life disposal scenario is environmentally beneficial because of the low environmental burden generated from human toxicity, terrestrial ecotoxicity, freshwater ecotoxicity, and marine ecotoxicity categories. Landfill and incineration technologies have a lower and higher environmental burden than the e-waste recycling with an end-life disposal scenario, respectively. The key factors in reducing the overall environmental impact of e-waste recycling are optimizing energy consumption efficiency, reducing wastewater and solid waste effluent, increasing proper e-waste treatment amount, avoiding e-waste disposal to landfill and incineration sites, and clearly defining the duties of all stakeholders (e.g., manufacturers, retailers, recycling companies, and consumers)

  5. Life cycle assessment of electronic waste treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jinglan, E-mail: hongjing@sdu.edu.cn [Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Shandong University Climate Change and Health Center, Public Health School, Shandong University, Jinan 250012 (China); Shi, Wenxiao [Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Wang, Yutao [School of Life Science, Shandong University, Shanda South Road 27, Jinan 250100 (China); Chen, Wei [Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan 250100 (China); Li, Xiangzhi, E-mail: xiangzhi@sdu.edu.cn [School of Medicine, Shandong University, Jinan 250012 (China)

    2015-04-15

    Highlights: • Life cycle assessment of electronic waste recycling is quantified. • Key factors for reducing the overall environmental impact are indentified. • End-life disposal processes provide significant environmental benefits. • Efficiently reduce the improper disposal amount of e-waste is highly needed. • E-waste incineration can generate significant environmental burden. - Abstract: Life cycle assessment was conducted to estimate the environmental impact of electronic waste (e-waste) treatment. E-waste recycling with an end-life disposal scenario is environmentally beneficial because of the low environmental burden generated from human toxicity, terrestrial ecotoxicity, freshwater ecotoxicity, and marine ecotoxicity categories. Landfill and incineration technologies have a lower and higher environmental burden than the e-waste recycling with an end-life disposal scenario, respectively. The key factors in reducing the overall environmental impact of e-waste recycling are optimizing energy consumption efficiency, reducing wastewater and solid waste effluent, increasing proper e-waste treatment amount, avoiding e-waste disposal to landfill and incineration sites, and clearly defining the duties of all stakeholders (e.g., manufacturers, retailers, recycling companies, and consumers)

  6. Low cost UV-Ozone reactor mounted for treatment of electrode anodes used in P-OLEDs devices

    Directory of Open Access Journals (Sweden)

    Emerson Roberto Santos

    Full Text Available Abstract Low cost UV-Ozone reactor using a high pressure mercury vapor lamp of 80 watts without outer bulb showed good results for treatment of ITO films used as anode electrode in the assembly of P-OLED (polymer-organic light emitting diode devices. This study revealed 20 minutes as effective treatment time and it was verified also that the effect of UV-Ozone treatment loses its efficiency as the elapsed time increases. It was analyzed with measurements of contact angle using a droplet of PEDOT:PSS polymer. P-OLEDs devices were mounted with architecture: ITO/PEDOT:PSS/PVK/Alq3/Al. The PVK polymer was diluted in organic solvent of 1,2,4-trichlorobenzene with concentrations of: 5, 10, 20 and 30 mg/mL. Results revealed better performance of P-OLED devices for concentration of 5 mg/mL resulting in lower threshold voltage, elevation of electrical current and similar diode curve.

  7. Elimination of micropollutants and transformation products from a wastewater treatment plant effluent through pilot scale ozonation followed by various activated carbon and biological filters.

    Science.gov (United States)

    Knopp, Gregor; Prasse, Carsten; Ternes, Thomas A; Cornel, Peter

    2016-09-01

    Conventional wastewater treatment plants are ineffective in removing a broad range of micropollutants, resulting in the release of these compounds into the aquatic environment, including natural drinking water resources. Ozonation is a suitable treatment process for micropollutant removal, although, currently, little is known about the formation, behavior, and removal of transformation products (TP) formed during ozonation. We investigated the elimination of 30 selected micropollutants (pharmaceuticals, X-ray contrast media, industrial chemicals, and TP) by biological treatment coupled with ozonation and, subsequently, in parallel with two biological filters (BF) or granular activated carbon (GAC) filters. The selected micropollutants were removed to very different extents during the conventional biological wastewater treatment process. Ozonation (specific ozone consumption: 0.87 ± 0.29 gO3 gDOC(-1), hydraulic retention time: 17 ± 3 min) eliminated a large number of the investigated micropollutants. Although 11 micropollutants could still be detected after ozonation, most of these were eliminated in subsequent GAC filtration at bed volumes (BV) of approximately 25,000 m(3) m(-3). In contrast, no additional removal of micropollutants was achieved in the BF. Ozonation of the analgesic tramadol led to the formation of tramadol-N-oxide that is effectively eliminated by GAC filters, but not by BF. For the antiviral drug acyclovir, the formation of carboxy-acyclovir was observed during activated sludge treatment, with an average concentration of 3.4 ± 1.4 μg L(-1) detected in effluent samples. Subsequent ozonation resulted in the complete elimination of carboxy-acyclovir and led to the formation of N-(4-carbamoyl-2-imino-5-oxo imidazolidin)-formamido-N-methoxyacetetic acid (COFA; average concentration: 2.6 ± 1.0 μg L(-1)). Neither the BF nor the GAC filters were able to remove COFA. These results highlight the importance of considering TP in the

  8. Ozone treatment of olive mill wastewater; Tratamiento con ozono de las aguas residuales de almazara

    Energy Technology Data Exchange (ETDEWEB)

    Beltran de Heredia Alonso, J.; Torregrosa Anton, J.; Garcia Rodriguez, J.; Dominguez Vargas, J. R. [Universidad de Extremadura. Badajoz (Spain)

    2000-07-01

    In the present work, the ozonization of olive mill wastewater has been studied. The evolution process was followed by measuring the chemical oxygen demand, the aromaticity and the contents of phenolic compounds. The aromaticity conversion ranged between 4.85 and 21% chemical oxygen demand degradation varied from 3.25 to 19.4% and the total polyphenolic reduction varied between 6.86 and 43.7%. The ozone consumption in the reduction of each variable was determined, being the average values of 57.2 g COD/mol O{sub 3} 2.9 un. Abs/mol O{sub 2} and 3.3 g poly phen./mol O{sub 3}. Finally, considering a first order kinetic equation with respect to each reactant, the apparent kinetic constants are evaluated for the studied variables. (Author) 19 refs.

  9. Advanced treatment of biologically pretreated coal chemical industry wastewater using the catalytic ozonation process combined with a gas-liquid-solid internal circulating fluidized bed reactor.

    Science.gov (United States)

    Li, Zhipeng; Liu, Feng; You, Hong; Ding, Yi; Yao, Jie; Jin, Chao

    2018-04-01

    This paper investigated the performance of the combined system of catalytic ozonation and the gas-liquid-solid internal circulating fluidized bed reactor for the advanced treatment of biologically pretreated coal chemical industry wastewater (CCIW). The results indicated that with ozonation alone for 60min, the removal efficiency of chemical oxygen demand (COD) could reach 34%. The introduction of activated carbon, pumice, γ-Al 2 O 3 carriers improved the removal performance of COD, and the removal efficiency was increased by 8.6%, 4.2%, 2%, respectively. Supported with Mn, the catalytic performance of activated carbon and γ-Al 2 O 3 were improved significantly with COD removal efficiencies of 46.5% and 41.3%, respectively; however, the promotion effect of pumice supported with Mn was insignificant. Activated carbon supported with Mn had the best catalytic performance. The catalytic ozonation combined system of MnO X /activated carbon could keep ozone concentration at a lower level in the liquid phase, and promote the transfer of ozone from the gas phase to the liquid phase to improve ozonation efficiency.

  10. Is ozonation environmentally benign for reverse osmosis concentrate treatment? Four-level analysis on toxicity reduction based on organic matter fractionation.

    Science.gov (United States)

    Weng, Jingxia; Jia, Huichao; Wu, Bing; Pan, Bingcai

    2018-01-01

    Ozonation is a promising option to treat reverse osmosis concentrate (ROC). However, a systematic understanding and assessment of ozonation on toxicity reduction is insufficient. In this study, ROC sampled from a typical industrial park wastewater treatment plant of China was fractionated into hydrophobic acid (HOA), hydrophobic base (HOB), hydrophobic neutral (HON), and hydrophilic fraction (HI). Systematic bioassays covering bacteria, algae, fish, and human cell lines were conducted to reveal the role of ozonation in toxicity variation of the four ROC fractions. HOA in the raw ROC exhibited the highest toxicity, followed by HON and HI. Ozonation significantly reduced total organic carbon (TOC) and UV 254 values in HOA, HON, and HI and their toxicity except in HOB. Correlation analysis indicated that chemical data (TOC and UV 254 ) of HOA and HON correlated well with their toxicities; however, poor correlations were observed for HOB and HI, suggesting that a battery of toxicity assays is necessary. This study indicates that TOC reduction during ozonation could not fully reflect the toxicity issue, and toxicity assessment is required in conjunction with the chemical data to evaluate the effectiveness of ozonation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Plasma treatment for producing electron emitters

    Science.gov (United States)

    Coates, Don Mayo; Walter, Kevin Carl

    2001-01-01

    Plasma treatment for producing carbonaceous field emission electron emitters is disclosed. A plasma of ions is generated in a closed chamber and used to surround the exposed surface of a carbonaceous material. A voltage is applied to an electrode that is in contact with the carbonaceous material. This voltage has a negative potential relative to a second electrode in the chamber and serves to accelerate the ions toward the carbonaceous material and provide an ion energy sufficient to etch the exposed surface of the carbonaceous material but not sufficient to result in the implantation of the ions within the carbonaceous material. Preferably, the ions used are those of an inert gas or an inert gas with a small amount of added nitrogen.

  12. Electron-beam flue gas treatment

    International Nuclear Information System (INIS)

    Aoki, Shinji

    1990-01-01

    A new flue gas treatment process (EBA process) using an electron beam will be discussed. This EBA process is attracting worldwide attention as a new effective measure for solving acid rain problems and jointly developed by Ebara Corporation and the Japan Atomic Energy Research Institute. This process has many advantages: a) a dry process capable of removing high level SO x and NO x simultaneously, b) a process simple and easy to operate, c) production of agricultural fertilizers as salable by-products, and d) minimal installation space. Test results from the demonstration plant (max. gas flow rate of 24,000 m 3 N/h) which was erected in a coal-fired power station in Indianapolis, Indiana, U.S.A. will be presented. (author)

  13. Industrial wastewater treatment with electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Han, Bumsoo; Ko, Jaein; Kim, Jinkyu; Kim, Yuri; Chung, Wooho [Central Research Institute of Samsung Heavy Industries Co., Taejon (Korea)

    2001-03-01

    Global withdrawals of water to satisfy human demands have grown dramatically in this century. Between 1900 and 1945, water consumption increased by over six times, more than double the rate of population growth. This rapid growth in water demand is due to the increasing reliance on irrigation to achieve food security, the growth of industrial uses, and the increasing use per capita for domestic purposes. Given the seriousness of the situation and future risk of crises, there is an urgent need to develop the water-efficient technologies including economical treatment methods of wastewater and polluted water. In the Central Research Institute of Samsung Heavy Industries (SHI), many industrial wastewater including leachate from landfill area, wastewater from papermill, dyeing complex, petrochemical processes, etc. are under investigation with electron beam irradiation. For the study of treating dyeing wastewater combined with conventional facilities, an electron beam pilot plant for treating 1,000m{sup 3}/day of wastewater from 80,000m{sup 3}/day of total dyeing wastewater has constructed and operated in Taegu Dyeing Industrial Complex. A commercial plant for re-circulation of wastewater from Papermill Company is also designed for S-paper Co. in Cheongwon City, and after the successful installation, up to 80% of wastewater could be re-used in paper producing process. (author)

  14. Industrial wastewater treatment with electron beam

    International Nuclear Information System (INIS)

    Han, Bumsoo; Ko, Jaein; Kim, Jinkyu; Kim, Yuri; Chung, Wooho

    2001-01-01

    Global withdrawals of water to satisfy human demands have grown dramatically in this century. Between 1900 and 1945, water consumption increased by over six times, more than double the rate of population growth. This rapid growth in water demand is due to the increasing reliance on irrigation to achieve food security, the growth of industrial uses, and the increasing use per capita for domestic purposes. Given the seriousness of the situation and future risk of crises, there is an urgent need to develop the water-efficient technologies including economical treatment methods of wastewater and polluted water. In the Central Research Institute of Samsung Heavy Industries (SHI), many industrial wastewater including leachate from landfill area, wastewater from papermill, dyeing complex, petrochemical processes, etc. are under investigation with electron beam irradiation. For the study of treating dyeing wastewater combined with conventional facilities, an electron beam pilot plant for treating 1,000m 3 /day of wastewater from 80,000m 3 /day of total dyeing wastewater has constructed and operated in Taegu Dyeing Industrial Complex. A commercial plant for re-circulation of wastewater from Papermill Company is also designed for S-paper Co. in Cheongwon City, and after the successful installation, up to 80% of wastewater could be re-used in paper producing process. (author)

  15. Ozone Application for Tofu Waste Water Treatment and Its Utilisation for Growth Medium of Microalgae Spirulina sp

    Directory of Open Access Journals (Sweden)

    Hadiyanto Hadiyanto

    2018-01-01

    Full Text Available Tofu industries produce waste water containing high organic contents and suspendid solid which is harmful if directly discharged to the environment. This waste can lead to disruption of water quality and lowering the environmental carrying capacity of waters around the tofu industries. Besides, the tofu waste water still contains high nitrogen contents which can be used for microalgae growth. This study was aimed to reduce the pollution load (chemical oxygen demand-COD of tofue wastewater by using ozone treatments and to utilize nutrients in treated tofu waste water as medium growth of microalgae. The result showed that the reduction of COD by implementation of ozone treatment followed first order kinetic. Under variation of waste concentrations between 10-40%, the degradation rate constant was in the range of 0.00237-0.0149 min-1. The microalgae was able to grow in the tofue waste medium by the growth rate constants of 0.15-0.29 day-1. This study concluded that tofu waste was highly potent for microalgae growth.

  16. Ozone Application for Tofu Waste Water Treatment and Its Utilisation for Growth Medium of Microalgae Spirulina sp

    Science.gov (United States)

    Hadiyanto, Hadiyanto

    2018-02-01

    Tofu industries produce waste water containing high organic contents and suspendid solid which is harmful if directly discharged to the environment. This waste can lead to disruption of water quality and lowering the environmental carrying capacity of waters around the tofu industries. Besides, the tofu waste water still contains high nitrogen contents which can be used for microalgae growth. This study was aimed to reduce the pollution load (chemical oxygen demand-COD) of tofue wastewater by using ozone treatments and to utilize nutrients in treated tofu waste water as medium growth of microalgae. The result showed that the reduction of COD by implementation of ozone treatment followed first order kinetic. Under variation of waste concentrations between 10-40%, the degradation rate constant was in the range of 0.00237-0.0149 min-1. The microalgae was able to grow in the tofue waste medium by the growth rate constants of 0.15-0.29 day-1. This study concluded that tofu waste was highly potent for microalgae growth.

  17. Ozone Therapy in Dentistry

    Science.gov (United States)

    Domb, William C

    2014-01-01

    Summary The 21st century dental practice is quite dynamic. New treatment protocols and new materials are being developed at a rapid pace. Ozone dental therapy falls into the category of new treatment protocols in dentistry, yet ozone is not new at all. Ozone therapy is already a major treatment modality in Europe, South America and a number of other countries. What is provided here will not be an exhaustive scientific treatise so much as a brief general introduction into what dentists are now doing with ozone therapies and the numerous oral/systemic links that make this subject so important for physicians so that, ultimately, they may serve their patients more effectively and productively. PMID:25363268

  18. Tests in excess sludge minimization through cell membrane break-up by means of ozone at a municipal sewage treatment plant; Versuche zur Ueberschussschlamm-Minimierung durch Zellaufschluss mit Ozon auf einer kommunalen Klaeranlage

    Energy Technology Data Exchange (ETDEWEB)

    Ried, A.; Peters, B. [WEDECO Umweltdienstleistungen GmbH, Herford (Germany)

    1999-07-01

    Disposing of sewage sludge involves high cost. Therfore, processes to reduce sewage sludge are more and more in demand. One such process is the treatment with ozone. The company WEDESCO GmbH is also concerned with ozonification of sewage sludge and carries out tests on a technical scale at a municipal sewage treatment plant. The objective is to reduce the amount of sewage sludge by approximately 50 %, corresponding, in the present case, to the organic sludge portion. (orig.) [German] Da die Entsorgung dieses Klaerschlamms hohe Kosten verursacht, gewinnen Verfahren zur Klaerschlammreduzierung zunehmend an Bedeutung. Eine Moeglichkeit der Reduzierung des Klaerschlamms besteht in der Behandlung mit Ozon. Auch die WEDECO GmbH befasst sich mit der Ozonung von Klaerschlamm und fuehrt Versuche im grosstechnischen Massstab auf einer kommunalen Klaeranlage durch. Ziel dieser Versuche ist es, den anfallenden Klaerschlamm um ca. 50% zu reduzieren, was in diesem Anwendungsfall dem organischen Anteil des Schlamms entspricht. (orig.)

  19. Oxygen nitrogen and ozone: application in wastewater treatment and environment protection

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Julio A.G. [Oxigenio do Brasil, Sao Paulo, SP (Brazil)

    1993-12-31

    Oxygen`s versatility as an oxidant and as a combustion atmosphere provides clean solutions to different industries. Oxygen also finds excellent application for the regeneration of eutrophic surface waters where high biochemical oxygen demand loading demands extra available oxygen for life support. When even stronger oxidizing properties are needed, ozone may act as a supplement. Nitrogen, on the other hand, has excellent cooling capacity, resulting in practical application in solvent recapture, enabling processes to meet emission standards while allowing solvent recycle for reuse. 7 figs., 1 tab.

  20. Oxygen nitrogen and ozone: application in wastewater treatment and environment protection

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, Julio A.G. [Oxigenio do Brasil, Sao Paulo, SP (Brazil)

    1994-12-31

    Oxygen`s versatility as an oxidant and as a combustion atmosphere provides clean solutions to different industries. Oxygen also finds excellent application for the regeneration of eutrophic surface waters where high biochemical oxygen demand loading demands extra available oxygen for life support. When even stronger oxidizing properties are needed, ozone may act as a supplement. Nitrogen, on the other hand, has excellent cooling capacity, resulting in practical application in solvent recapture, enabling processes to meet emission standards while allowing solvent recycle for reuse. 7 figs., 1 tab.

  1. Effect of ultrasonic and ozone pre-treatments on pharmaceutical waste activated sludge's solubilisation, reduction, anaerobic biodegradability and acute biological toxicity.

    Science.gov (United States)

    Pei, Jin; Yao, Hong; Wang, Hui; Shan, Dan; Jiang, Yichen; Ma, Lanqianya; Yu, Xiaohua

    2015-09-01

    Ultrasonic and ozone pre-treatment technologies were employed in this study to improve the anaerobic digestion efficiency of pharmaceutical waste activated sludge. The sludge solubilisation achieved 30.01% (150,000 kJ/kg TS) and 28.10% (0.1g O3/g TS) after ultrasonic treatment and ozone treatment. The anaerobic biodegradability after ultrasonic treatment was higher compared to ozonation due to the higher cumulative methane volume observed after 6 days (249 ml vs 190 ml). The ozonated sludge released the highest concentration of Cu(2+) into the liquid phase (6.640 mg L(-1)) compared to 0.530 mg/L for untreated sludge and 0.991 mg/L for sonicated sludge. The acute toxicity test measured by luminescent bacteria showed that anaerobic digestion could degrade toxic compounds and result in a reduction in toxicity. The main mechanism of action led to some differences in the treated sludge exhibiting higher potential for methane production from pharmaceutical waste sludge with ultrasonic treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Dehalogenation, degradation and mineralization of diuron by peroxone (peroxide/ozone) treatment.

    Science.gov (United States)

    Catalkaya, Ebru Cokay; Kargi, Fikret

    2009-05-01

    Removal of diuron from aqueous solution by peroxone (hydrogen peroxide/ozone) oxidation was investigated using Box-Behnken statistical experiment design and the response surface methodology (RSM). Effects of diuron, H(2)O(2) concentrations and initial pH on the extent of diuron, total organic carbon (TOC) and adsorbable organic halogen (AOX) removals were investigated. Ozone dose was kept constant at 45 mg min(-1). Optimum reagent doses yielding the highest diuron, TOC and AOX removals were also determined. Hydrogen peroxide dose and pH were the most effective parameters for pesticide removal while hydrogen peroxide dose had the most significant effect on AOX removal (dehalogenation). All parameters affected mineralization (TOC removal) of diuron. Nearly complete removal of diuron was achieved within 5 minutes, while complete mineralization and dehalogenation were not achieved even within 60 minutes at high diuron doses indicating formation of some intermediate products. The optimal H(2)O(2)/pH/diuron ratio resulting in the maximum pesticide (100%), TOC (82%) and AOX (95%) removal was found to be 340/8/10.

  3. Electron Beam Treatment of Toxic Chemicals

    International Nuclear Information System (INIS)

    Jung, In Ha; Lee, Myun Joo; Lee, Oh Mi; Kim, Tae Hoon

    2011-01-01

    Polychlorinated biphenyls (PCBs) were commercially produced from 1920s as complex mixtures containing multiple isomers for a variety of applications. They are very toxic, chemically stable and resist microbial, photochemical, chemical, and thermal degradation. The public, legal, and scientific concerns about PCBs arose from research indicating they were environmental contaminants that had a potential to adversely impact the environment, and, therefore, were undesirable as commercial products. Eventually, most producers reduced or stopped production of PCBs in the 1970s. Stockholm convention on POPs (Persistent Organic Pollutants), which was effective on May 2004 and 151 nations including Korea were joined on June 2005, asked to dispose of PCBs by 2028 with environmental friendly methods. Korean government also has declared to perform by 2015. According to the Environmental law of Korea, over 2 ppm of PCBs has to be decomposed by legal methods of incineration and thermal destruction. But those are inapplicable owing to the environmental groups. KAERI(Korea Atomic Energy Research Institute) has recently developed a remarkable technology for radiation treatment of toxic chemicals including chlorides using an electron beam accelerator

  4. Impulse approximation treatment of electron-electron excitation and ionization in energetic ion-atom collisions

    International Nuclear Information System (INIS)

    Zouros, T.J.M.; Lee, D.H.; Sanders, J.M.; Richard, P.

    1993-01-01

    The effect of electron-electron interactions between projectile and target electrons observed in recent measurements of projectile K-shell excitation and ionization using 0 projectile Auger electron spectroscopy are analysed within the framework of the impulse approximation (IA). The IA formulation is seen to give a good account of the threshold behavior of both ionization and excitation, while providing a remarkably simple intuitive picture of such electron-electron interactions in ion-atom collisions in general. Thus, the applicability of the IA treatment is extended to cover most known processes involving such interactions including resonance transfer excitation, binary encounter electron production, electron-electron excitation and ionization. (orig.)

  5. Effects of UV-Ozone Treatment on Sensing Behaviours of EGFETs with Al2O3 Sensing Film

    Directory of Open Access Journals (Sweden)

    Cuiling Sun

    2017-12-01

    Full Text Available The effects of UV-ozone (UVO treatment on the sensing behaviours of extended-gate field-effect transistors (EGFETs that use Al2O3 as the sensing film have been investigated. The Al2O3 sensing films are UVO-treated with various duration times and the corresponding EGFET sensing behaviours, such as sensitivity, hysteresis, and long-term stability, are electrically evaluated under various measurement conditions. Physical analysis is also performed to characterize the surface conditions of the UVO-treated sensing films using X-ray photoelectron spectroscopy and atomic force microscopy. It is found that UVO treatment effectively reduces the buried sites in the Al2O3 sensing film and subsequently results in reduced hysteresis and improved long-term stability of EGFET. Meanwhile, the observed slightly smoother Al2O3 film surface post UVO treatment corresponds to decreased surface sites and slightly reduced pH sensitivity of the Al2O3 film. The sensitivity degradation is found to be monotonically correlated with the UVO treatment time. A treatment time of 10 min is found to yield an excellent performance trade-off: clearly improved long-term stability and reduced hysteresis at the cost of negligible sensitivity reduction. These results suggest that UVO treatment is a simple and facile method to improve the overall sensing performance of the EGFETs with an Al2O3 sensing film.

  6. Removal of pharmaceuticals and unspecified contaminants in sewage treatment effluents by activated carbon filtration and ozonation: Evaluation using biomarker responses and chemical analysis.

    Science.gov (United States)

    Beijer, Kristina; Björlenius, Berndt; Shaik, Siraz; Lindberg, Richard H; Brunström, Björn; Brandt, Ingvar

    2017-06-01

    Traces of active pharmaceutical ingredients (APIs) and other chemicals are demonstrated in effluents from sewage treatment plants (STPs) and they may affect quality of surface water and eventually drinking water. Treatment of effluents with granular activated carbon (GAC) or ozone to improve removal of APIs and other contaminants was evaluated at two Swedish STPs, Käppala and Uppsala (88 and 103 APIs analyzed). Biomarker responses in rainbow trout exposed to regular and additionally treated effluents were determined. GAC and ozone treatment removed 87-95% of the total concentrations of APIs detected. In Käppala, GAC removed 20 and ozonation (7 g O 3 /m 3 ) 21 of 24 APIs detected in regular effluent. In Uppsala, GAC removed 25 and ozonation (5.4 g O 3 /m 3 ) 15 of 25 APIs detected in effluent. GAC and ozonation also reduced biomarker responses caused by unidentified pollutants in STP effluent water. Elevated ethoxyresorufin-O-deethylase (EROD) activity in gills was observed in fish exposed to effluent in both STPs. Gene expression analysis carried out in Käppala showed increased concentrations of cytochrome P450 (CYP1As and CYP1C3) transcripts in gills and of CYP1As in liver of fish exposed to effluent. In fish exposed to GAC- or ozone-treated effluent water, gill EROD activity and expression of CYP1As and CYP1C3 in gills and liver were generally equal to or below levels in fish held in tap water. The joint application of chemical analysis and sensitive biomarkers proved useful for evaluating contaminant removal in STPs with new technologies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. MRI-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture for treatment of cervical disc herniation: an initial experience

    International Nuclear Information System (INIS)

    Liu Ming; Li Chengli; Lu Yubo; Huang Jie; Song Jiqing; Li Lei; Bao Shougang; Cao Qianqian; Wu Lebin

    2010-01-01

    Objective: To explore the value of MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture for treatment of cervical disc herniation. Methods: Eight herniated cervical discs in 7 patients were diagnosed by MRI, inclluding 5 discs of lateral protruding type, 2 discs of paramedian protruding type and one disc of central protruding type. All patients underwent MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture. The procedures were guided by a set of 0.23 T open MR system mounted with iPath 200 optical tracking system. The herniated portion of the disc was punctured with a 14 G MR-comparible needle in the healthy side via anterolateral oblique route. The interventional steps were as follows: firstly, cut herniated part with percutaneous discectomy probe and inject 2ml oxygen-ozone mixture of 60 μg/ml; secondly, retreat the needle to the disc center, resect nucleus pulposus, and inject 2 ml oxygen-ozone mixture of 60 μg/ml; secondly, retreat the needle to the disc center, resect nucleus pulposus, and inject 2 ml oxygen-ozone mixture of 60 μg/ml. All patients were followed up for 6 months, with 4 patients by telephone and 3 patients in outpatient clinic. The effect of treatment was evaluated according to Williams postoperative assessment standard. Results: All procedures were performed successfully. The clinical outcome was evaluated as excellent in 5 cases, good in 1 cases and fair in 1 case. The total ratio of excellent and good was 85.7%. No serious complication occurred expect 1 case with intraoperative paroxysmal pain. Conclusion: MR imaging-guided percutaneous cervical discectomy and discolysis with oxygen-ozone mixture was a safe, effective and minimally invasive method for the treatment of cervical disc herniation. (authors)

  8. Inhibition of trihalomethane formation in city water by radiation-ozone treatment and rapid composting of radiation disinfected sewage sludge

    International Nuclear Information System (INIS)

    Takehisa, M.; Arai, H.; Arai, M.

    1985-01-01

    Humic acid and Fulvic acid in natural water are precursors of carcinogenic THM which is formed during chlorine disinfection in city water processing. The radiation-oxidation process in the presence of ozone is effective to remove the precursors. The THM formation was reduced more than the decrease in TOC by the combination treatment. This is mainly due to a change in the chemical structure of the oxidation products. A composting of radiation disinfected sludge cake for agricultural reuse could be achieved within 3 days primary fermentation in a sewage plant. The rapid fermentation with use of radiation is effective to scale down of a fermentor of composting plant and the process reduces a health risk from the workers as well as final users. (author)

  9. Inhibition of trihalomethane formation in city water by radiation-ozone treatment and rapid composting of radiation disinfected sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Takehisa, M; Arai, H; Arai, M

    1985-01-01

    Humic acid and Fulvic acid in natural water are precursors of carcinogenic THM which is formed during chlorine disinfection in city water processing. The radiation-oxidation process in the presence of ozone is effective to remove the precursors. The THM formation was reduced more than the decrease in TOC by the combination treatment. This is mainly due to a change in the chemical structure of the oxidation products. A composting of radiation disinfected sludge cake for agricultural reuse could be achieved within 3 days primary fermentation in a sewage plant. The rapid fermentation with use of radiation is effective to scale down a fermentor of a composting plant and the process reduces health risk for the workers as well as final users.

  10. Integration of ozonation and an anaerobic sequencing batch reactor (AnSBR) for the treatment of cherry stillage.

    Science.gov (United States)

    Alvarez, Pedro M; Beltrán, Fernando J; Rodríguez, Eva M

    2005-01-01

    Cherry stillage is a high strength organic wastewater arising from the manufacture of alcoholic products by distillation of fermented cherries. It is made up of biorefractory polyphenols in addition to readily biodegradable organic matter. An anaerobic sequencing batch reactor (AnSBR) was used to treat cherry stillage at influent COD ranging from 5 to 50 g/L. Different cycle times were selected to test biomass organic loading rates (OLR(B)), from 0.3 to 1.2 g COD/g VSS.d. COD and TOC efficiency removals higher than 80% were achieved at influent COD up to 28.5 g/L but minimum OLR(B) tested. However, as a result of the temporary inhibition of acetogens and methanogens, volatile fatty acids (VFA) noticeably accumulated and methane production came to a transient standstill when operating at influent COD higher than 10 g/L. At these conditions, the AnSBR showed signs of instability and could not operate efficiently at OLR(B) higher than 0.3 g COD/g VSS.d. A feasible explanation for this inhibition is the presence of toxic polyphenols in cherry stillage. Thus, an ozonation step prior to the AnSBR was observed to be useful, since more than 75% of polyphenols could be removed by ozone. The integrated process was shown to be a suitable treatment technology as the following advantages compared to the single AnSBR treatment were observed: greater polyphenols and color removals, higher COD and TOC removal rates thus enabling the process to effectively operate at higher OLR, higher degree of biomethanation, and good stability with less risk of acidification.

  11. Inactivation characteristics of ozone and electrolysis process for ballast water treatment using B. subtilis spores as a probe.

    Science.gov (United States)

    Jung, Youmi; Yoon, Yeojoon; Hong, Eunkyung; Kwon, Minhwan; Kang, Joon-Wun

    2013-07-15

    Since ballast water affects the ocean ecosystem, the International Maritime Organization (IMO) sets a standard for ballast water management and might impose much tighter regulations in the future. The aim of this study is to evaluate the inactivation efficiency of ozonation, electrolysis, and an ozonation-electrolysis combined process, using B. subtilis spores. In seawater ozonation, HOBr is the key active substance for inactivation, because of rapid reactivity of ozone with Br(-) in seawater. In seawater electrolysis, it is also HOBr, but not HOCl, because of the rapid reaction of HOCl with Br(-), which has not been recognized carefully, even though many electrolysis technologies have been approved by the IMO. Inactivation pattern was different in ozonation and electrolysis, which has some limitations with the tailing or lag-phase, respectively. However, each deficiency can be overcome with a combined process, which is most effective as a sequential application of ozonation followed by electrolysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Surface chemical and electronic properties of In{sub 2}O{sub 3} and In{sub 2}O{sub 3-x} nanoparticles for ozone detection

    Energy Technology Data Exchange (ETDEWEB)

    Himmerlich, Marcel; Krischok, Stefan [Institut fuer Physik and Institut fuer Mikro- und Nanotechnologien, TU Ilmenau, PF 100565, 98684 Ilmenau (Germany); Wang, Chunyu; Cimalla, Volker; Ambacher, Oliver [Fraunhofer-Institut fuer Angewandte Festkoerperphysik, Tullastr. 72, 79108 Freiburg im Breisgau (Germany)

    2012-07-01

    The electrical properties of indium oxide nanoparticle films can be tuned by variation of growth temperature as well as rapid thermal annealing, UV-irradiation and ozone-induced oxidation. The high O{sub 3} sensitivity of indium oxide thin films is strongly linked to their structural and electronic properties. Especially, the alteration of the surface electron accumulation plays an important role in the change of the film resistivity upon O{sub 3} interaction and UV-induced regeneration. We analyse the changes of indium oxide surface properties with respect to varying crystallinity using AFM, XPS and UPS. Compared to stoichiometric In{sub 2}O{sub 3} thin films, indium oxide nanoparticles exhibit a high oxygen deficiency and hence a high defect density at the nanoparticle surface. After growth, these defects are saturated by hydrocarbons due to the incomplete decomposition of precursors during low temperature MOCVD. The defects and the changed stoichiometry have impact on the surface band alignment. Upon ozone-induced oxidation and UV photoreduction a reversible change in band bending, surface dipole and O adsorption density is found and will be discussed in context with electron transport characteristics and thermal properties.

  13. Effect of Ozonation and Biological Activated Carbon Treatment of Wastewater Effluents on Formation of N-nitrosamines and Halogenated Disinfection Byproducts.

    Science.gov (United States)

    Chuang, Yi-Hsueh; Mitch, William A

    2017-02-21

    Ozonation followed by biological activated carbon (O 3 /BAC) is being considered as a key component of reverse osmosis-free advanced treatment trains for potable wastewater reuse. Using a laboratory-scale O 3 /BAC system treating two nitrified wastewater effluents, this study characterized the effect of different ozone dosages (0-1.0 mg O 3 /mg dissolved organic carbon) and BAC empty bed contact times (EBCT; 15-60 min) on the formation after chlorination or chloramination of 35 regulated and unregulated halogenated disinfection byproducts (DBPs), 8 N-nitrosamines, and bromate. DBP concentrations were remarkably similar between the two wastewaters across O 3 /BAC conditions. Ozonation increased bromate, TCNM, and N-nitrosodimethylamine, but ozonation was less significant for other DBPs. DBP formation generally decreased significantly with BAC treatment at 15 min EBCT, but little further reduction was observed at higher EBCT where low dissolved oxygen concentrations may have limited biological activity. The O 3 /BAC-treated wastewaters met regulatory levels for trihalomethanes (THMs), haloacetic acids (HAAs), and bromate, although N-nitrosodimethylamine exceeded the California Notification Level in one case. Regulated THMs and HAAs dominated by mass. When DBP concentrations were weighted by measures of their toxic potencies, unregulated haloacetonitriles, haloacetaldehydes, and haloacetamides dominated. Assuming toxicity is additive, the calculated DBP-associated toxicity of the O 3 /BAC-treated chloraminated effluents were comparable or slightly higher than those calculated in a recent evaluation of Full Advanced Treatment trains incorporating reverse osmosis.

  14. Electron beam application in gas waste treatment in China

    International Nuclear Information System (INIS)

    Wu Haifeng

    2003-01-01

    In the most recent decade, electron beam waste treatment technology attracted serious attention from environment policymaker and industrial leaders in power industry in China. Starting in middle of 1980's, Chinese research institute began experiment of electron beam treatment on flue gas. By the end of 2000, two 10,000 cubic meters per hour small scale electron beam gas purifying station were established in Sichuang province and Beijing. Several electron beam gas purifying demonstration projects are under construction. With robust economy and strong energy demand, needless to say, in near future, electron beam gas purifying technology will have a bright prospect in China. (author)

  15. The use of ozone as microbiocide in cooling water treatment - experiences with an ''All-Organic'' program; Ozon als Mikrobizid bei der Kuehlwasserbehandlung - Praxiserfahrungen mit einem ''All-Organic'' Programm

    Energy Technology Data Exchange (ETDEWEB)

    Noks, E.; Olkis, A. [Deutsche Nalco Chemie GmbH, Frankfurt am Main (Germany); Kleinstueck, R. [Bayer AG, Leverkusen (Germany); Johnson, D.A. [Nalco Chemical Co., Naperville (United States)

    1999-10-01

    Since 1995, at the plant EZH Rotterdam, the practice of using ozone as microbiocide in the cooling circuit that uses a poor quality makeup water has proven to be successful. The strict limits for aqueous and emission protection from the plant can be maintained. Careful monitoring of the system is a key to the success of the cooling water treatment. The determining factor in judging the microbiological activity and effectiveness of the ozone addition was the regular determination of ATP values and total bacterial count in the system. Limiting ozone concentrations to the amount needed by the system helps to keep the degradation rate of the organic inhibitors under control and, by minimizing the treatment level, the treatment functions in an environmentally friendly and effective manner. Recovery rates of approximately 80% were measured for the phosphonate PBTC, the stabilizers and dispersants. The corrosion rates for steel and copper are low considering the makeup water quality. The combination of inhibitors controlled the tendency for deposits to form. Previous research in the laboratory and industry have shown that the basic components of the cooling water formulations, phosphonates, react very differently when placed in contact with ozone. In order of decreasing ozone stability they are: PBTC>HEDP>ATMP. A six-month trial was performed in a cooling circuit at Bayer AG in Dormagen using a PBTC-containing, stabilized phosphate treatment program. In spite of the high half-life of the cooling water in the system, it was found that the PBTC was stable with a recovery rate of 50-80%. (orig.) [German] Der seit 1995 praktizerte Einsatz von Ozon als Mikrobizid im Kuehlkreislauf des Kraftwerks EZH Rotterdam mit relativ stark vorbelastetem Zusatzwasser ist eine erfolgreiche Problemloesung. Die strengen Auflagen zum Gewaesser- und Immissionsschutz koennen vom Kraftwerk eingehalten werden. Sorgfaeltige Ueberwachung des Systems ist ein Kernstueck des Erfolgs der

  16. Application of ultraviolet, ozone, and advanced oxidation treatments to washwaters to destroy nitrosamines, nitramines, amines, and aldehydes formed during amine-based carbon capture.

    Science.gov (United States)

    Shah, Amisha D; Dai, Ning; Mitch, William A

    2013-03-19

    Although amine-based CO(2) absorption is a leading contender for full-scale postcombustion CO(2) capture at power plants, concerns have been raised about the potential release of carcinogenic N-nitrosamines and N-nitramines formed by reaction of exhaust gas NO(x) with the amines. Experiments with a laboratory-scale pilot unit suggested that washwater units meant to scrub contaminants from absorber unit exhaust could potentially serve as a source of N-nitrosamines via reactions of residual NO(x) with amines accumulating in the washwater. Dosage requirements for the continuous treatment of the washwater recycle line with ultraviolet (UV) light for destruction of N-nitrosamines and N-nitramines, and with ozone or hydroxyl radical-based advanced oxidation processes (AOPs) for destruction of amines and aldehydes, were evaluated. Although amine destruction. Ozone achieved 90% amine removal in washwaters at 5-12 molar excess of ozone, indicating transferred dosage levels of ∼100 mg/L for 90% removal in a first-stage washwater unit, but likely only ∼10 mg/L if applied to a second-stage washwater. Accurate dosage and cost estimates would require pilot testing to capture synergies between UV and ozone treatments.

  17. Evaluation of sorghum flour functionality and quality characteristics of gluten-free bread and cake as influenced by ozone treatment.

    Science.gov (United States)

    Marston, Kathryn; Khouryieh, Hanna; Aramouni, Fadi

    2015-12-01

    Commercially milled food-grade sorghum flour was subjected to ozone at the rate of 0.06 L/min for 15, 30, and 45 min. The pH of ozone-treated flour decreased as exposure time increased. The L* (lightness) values of sorghum flour significantly increased (p cake volume significantly increased as ozonation time increased. Additionally, longer ozonation exposure times increased cells per slice area, lightness, and slice brightness values in gluten-free cakes while reducing crumb firmness. Despite improving lightness and slice brightness values, ozonation did not significantly increase the specific volume of gluten-free batter-based bread. While ozonation improved the volume and texture in cakes, it did not have the same positive effects on gluten-free bread. Bread made from ozonated sorghum flour had an open ragged structure with equivalent volume to the control flour. In both applications, the increased brightness and lightness values due to ozone exposure is recommended to increase the acceptability of sorghum products. © The Author(s) 2014.

  18. Insights into the Electronic Structure of Ozone and Sulfur Dioxide from Generalized Valence Bond Theory: Bonding in O3 and SO2.

    Science.gov (United States)

    Takeshita, Tyler Y; Lindquist, Beth A; Dunning, Thom H

    2015-07-16

    There are many well-known differences in the physical and chemical properties of ozone (O3) and sulfur dioxide (SO2). O3 has longer and weaker bonds than O2, whereas SO2 has shorter and stronger bonds than SO. The O-O2 bond is dramatically weaker than the O-SO bond, and the singlet-triplet gap in SO2 is more than double that in O3. In addition, O3 is a very reactive species, while SO2 is far less so. These disparities have been attributed to variations in the amount of diradical character in the two molecules. In this work, we use generalized valence bond (GVB) theory to characterize the electronic structure of ozone and sulfur dioxide, showing O3 does indeed possess significant diradical character, whereas SO2 is effectively a closed shell molecule. The GVB results provide critical insights into the genesis of the observed difference in these two isoelectronic species. SO2 possesses a recoupled pair bond dyad in the a"(π) system, resulting in SO double bonds. The π system of O3, on the other hand, has a lone pair on the central oxygen atom plus a pair of electrons in orbitals on the terminal oxygen atoms that give rise to a relatively weak π interaction.

  19. Dobson ozone spectrophotometer modification.

    Science.gov (United States)

    Komhyr, W. D.; Grass, R. D.

    1972-01-01

    Description of a modified version of the Dobson ozone spectrophotometer in which several outdated electronic design features have been replaced by circuitry embodying more modern design concepts. The resulting improvement in performance characteristics has been obtained without changing the principle of operation of the original instrument.

  20. Ozonation control and effects of ozone on water quality in recirculating aquaculture systems

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Rojas-Tirado, Paula Andrea; Chetri, Ravi K.

    2018-01-01

    To address the undesired effect of chemotherapeutants in aquaculture, ozone has been suggested as an alternative to improve water quality. To ensure safe and robust treatment, it is vital to define the ozone demand and ozone kinetics of the specific water matrix to avoid ozone overdose. Different...... ozone dosages were applied to water in freshwater recirculating aquaculture systems (RAS). Experiments were performed to investigate ozone kinetics and demand, and to evaluate the effects on the water quality, particularly in relation to fluorescent organic matter. This study aimed at predicting...... a suitable ozone dosage for water treatment based on daily ozone demand via laboratory studies. These ozone dosages will be eventually applied and maintained at these levels in pilot-scale RAS to verify predictions. Selected water quality parameters were measured, including natural fluorescence and organic...

  1. Shelf-life extension of semi-dried buckwheat noodles by the combination of aqueous ozone treatment and modified atmosphere packaging.

    Science.gov (United States)

    Bai, Yi-Peng; Guo, Xiao-Nao; Zhu, Ke-Xue; Zhou, Hui-Ming

    2017-12-15

    The present study investigated the combined effects of aqueous ozone treatment and modified atmosphere packaging (MAP) on prolonging the shelf-life of semi-dried buckwheat noodles [SBWN; moisture content (22.5±0.5%)] at 25°C. Firstly, the different concentrations of ozonated water were used to make SBWN. Subsequently, SBWN prepared with ozonated water were packaged under six different conditions and stored for 11days. Changes in microbial, chemical-physical, textural properties and sensorial qualities of SWBN were monitored during storage. Microbiological results indicated that adopting 2.21mg/L of ozonated water resulted in a 1.8 log 10 CFU/g reduction of the initial microbial loads in SBWN. In addition, MAP suppressed the microbial growth with a concomitant reduction in the rates of acidification and quality deteriorations of SBWN. Finally, the shelf-life of sample packed under N 2 :CO 2 =30:70 was extended to 9days, meanwhile textural and sensorial characteristics were maintained during the whole storage period. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Ozone decomposition

    Directory of Open Access Journals (Sweden)

    Batakliev Todor

    2014-06-01

    Full Text Available Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers. Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates

  3. Ozone modeling

    Energy Technology Data Exchange (ETDEWEB)

    McIllvaine, C M

    1994-07-01

    Exhaust gases from power plants that burn fossil fuels contain concentrations of sulfur dioxide (SO{sub 2}), nitric oxide (NO), particulate matter, hydrocarbon compounds and trace metals. Estimated emissions from the operation of a hypothetical 500 MW coal-fired power plant are given. Ozone is considered a secondary pollutant, since it is not emitted directly into the atmosphere but is formed from other air pollutants, specifically, nitrogen oxides (NO), and non-methane organic compounds (NMOQ) in the presence of sunlight. (NMOC are sometimes referred to as hydrocarbons, HC, or volatile organic compounds, VOC, and they may or may not include methane). Additionally, ozone formation Alternative is a function of the ratio of NMOC concentrations to NO{sub x} concentrations. A typical ozone isopleth is shown, generated with the Empirical Kinetic Modeling Approach (EKMA) option of the Environmental Protection Agency's (EPA) Ozone Isopleth Plotting Mechanism (OZIPM-4) model. Ozone isopleth diagrams, originally generated with smog chamber data, are more commonly generated with photochemical reaction mechanisms and tested against smog chamber data. The shape of the isopleth curves is a function of the region (i.e. background conditions) where ozone concentrations are simulated. The location of an ozone concentration on the isopleth diagram is defined by the ratio of NMOC and NO{sub x} coordinates of the point, known as the NMOC/NO{sub x} ratio. Results obtained by the described model are presented.

  4. Ozone modeling

    International Nuclear Information System (INIS)

    McIllvaine, C.M.

    1994-01-01

    Exhaust gases from power plants that burn fossil fuels contain concentrations of sulfur dioxide (SO 2 ), nitric oxide (NO), particulate matter, hydrocarbon compounds and trace metals. Estimated emissions from the operation of a hypothetical 500 MW coal-fired power plant are given. Ozone is considered a secondary pollutant, since it is not emitted directly into the atmosphere but is formed from other air pollutants, specifically, nitrogen oxides (NO), and non-methane organic compounds (NMOQ) in the presence of sunlight. (NMOC are sometimes referred to as hydrocarbons, HC, or volatile organic compounds, VOC, and they may or may not include methane). Additionally, ozone formation Alternative is a function of the ratio of NMOC concentrations to NO x concentrations. A typical ozone isopleth is shown, generated with the Empirical Kinetic Modeling Approach (EKMA) option of the Environmental Protection Agency's (EPA) Ozone Isopleth Plotting Mechanism (OZIPM-4) model. Ozone isopleth diagrams, originally generated with smog chamber data, are more commonly generated with photochemical reaction mechanisms and tested against smog chamber data. The shape of the isopleth curves is a function of the region (i.e. background conditions) where ozone concentrations are simulated. The location of an ozone concentration on the isopleth diagram is defined by the ratio of NMOC and NO x coordinates of the point, known as the NMOC/NO x ratio. Results obtained by the described model are presented

  5. Ozone therapy and restorative dentistry: a literature review ...

    African Journals Online (AJOL)

    This approach is being further reinforced with the emergence of ozone therapy in the management of tooth decay. Ozone therapy is the treatment of the tooth with a mixture of oxygen and ozone. The aim of this review was to provide a comprehensive literature on ozone therapy and on the different areas of restorative dental ...

  6. Assessment of Fenton's reagent and ozonation as pre-treatments for increasing the biodegradability of aqueous diethanolamine solutions from an oil refinery gas sweetening process.

    Science.gov (United States)

    Durán-Moreno, A; García-González, S A; Gutiérrez-Lara, M R; Rigas, F; Ramírez-Zamora, R M

    2011-02-28

    The aim of this work was to evaluate the efficiency of three chemical oxidation processes for increasing the biodegradability of aqueous diethanolamine solutions (aqueous DEA solutions), to be used as pre-treatments before a biological process. The raw aqueous DEA solution, sourced from a sour gas sweetening plant at a Mexican oil refinery, was first characterized by standardized physico-chemical methods. Then experiments were conducted on diluted aqueous DEA solutions to test the effects of Fenton's reagent, ozone and ozone-hydrogen peroxide on the removal of some physicochemical parameters of these solutions. Lastly, biodegradability tests based on Dissolved Organic Carbon Die Away OECD301-A, were carried out on a dilution of the raw aqueous DEA solution and on the treated aqueous DEA solutions, produced by applying the best experimental conditions determined during the aforementioned oxidation tests. Experimental results showed that for aqueous DEA solutions treated with Fenton's reagent, the best degradation rate (70%) was obtained at pH 2.8, with Fe(2+) and H(2)O(2) at doses of 1000 and 10,000 mg/L respectively. In the ozone process, the best degradation (60%) was observed in aqueous DEA solution (100 mg COD/L), using 100 mg O(3)/L at pH 5. In the ozone-hydrogen peroxide process, no COD or DOC removals were observed. The diluted spent diethanolamine solution showed its greatest increase in biodegradability after a reaction period of 28 days when treated with Fenton's reagent, but after only 15 days in the case of ozonation. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Electron-beam and microwave treatment of some microbial strains

    International Nuclear Information System (INIS)

    Martin, D.; Ferdes, O.S.; Minea, R.; Tirlea, A.; Badea, M.; Plamadeala, S.; Ferdes, M.

    1998-01-01

    The experimental results concerning the combined effects of microwaves and accelerated electron beams on various microbial strains such as E. coli, Salmonella sp. and Monascus purpureus are presented. A special designed microwave applicator with a 2.45 GHz frequency CW magnetron of 850 maximum output power and with associate electronics that allow to control the microwave power, the current intensity, and the exposure time was used. The electron-beam irradiation was performed at different irradiation doses and at a dose rate of 1.5 - 2.0 kGy/min by using a linac at a mean electron energy about 6 MeV, mean bean current of 10 μA, pulse period of 3.5 μs and repetition frequency 100 Hz. The experiments were carried out in 5 variants: microwave treatment; electron-beam irradiation; microwaves followed by electron beam; electrons followed by microwaves; and simultaneous application of microwaves and electron beam. The microbiocidal effect was found to be enhanced by additional use of microwave energy to electron beam irradiation. Enhancement of inactivation rate is only remarkable for the microwave treatment or simultaneous electron beam and microwave irradiation at a temperature above the critical value at which microorganisms begin to perish by heat. Simultaneous irradiation with electron beam and microwaves results in a reduction of temperature and time as well as in the decrease of the upper limit of required electron beam absorbed dose for an assumed microbiological quality parameter. The results obtained indicate the occurrence of a synergistic effect of the two physical fields on a non-thermal basis. Hence, combined microwave-electron beam treatment may be applied as an effective method to reduce microbial load

  8. Ozone Pollution

    Science.gov (United States)

    Known as tropospheric or ground-level ozone, this gas is harmful to human heath and the environment. Since it forms from emissions of volatile organic compounds (VOCs) and nitrogen oxides (NOx), these pollutants are regulated under air quality standards.

  9. X-ray targeting puncture collagenase chemonucleolysis combined with injection of medical ozone for the treatment of lumbar disc herniation

    International Nuclear Information System (INIS)

    Yao Lin; Zhu Genfa

    2011-01-01

    Objective: To evaluate the clinical value of X-ray target puncture collagenase chemonucleolysis combined with injection of medical ozone for lumbar disc herniation. Methods: One thousand and sixty-two cases of lumbar disc herniation accepted collagenase chemonucleolysis combined with injection of medical ozone targeted by X-ray. The therapeutic effects after operation were analyzed. Results: Of all the 1062 cases, the effective rate of X-ray target puncture collagenase chemonucleolysis combined with injection of medical ozone was 95.3% at 3 months, 92.3% at 12 months, and 91.2% at 24 months after operation. Conclusion: X-ray target puncture collagenase chemonucleolysis combined with injection of medical ozone is a simple and safe method for the lumbar disc herniation. It also had fewer adverse reactions and better therapeutic effects. (authors)

  10. Electron beam treatments of electrophoretic ceramic coatings

    International Nuclear Information System (INIS)

    De Riccardis, M.F.; Carbone, D.; Piscopiello, E.; Antisari, M. Vittori

    2008-01-01

    In this work a method to densify ceramic coating obtained by electrophoresis and to improve its adhesion to the substrate is proposed. It consists in irradiating the coating surface by electron beam (EB). Alumina and alumina-zirconia coatings were deposited on stainless steel substrates and treated by low power EB. SEM, XRD and TEM characterizations demonstrated that the sintering occurred. Moreover, it is shown that on alumina-zirconia coating the EB irradiation produced a composite material consisting principally of tetragonal zirconia particles immersed in an amorphous alumina matrix. The adhesion stress of EB treated coating was estimated by stud pull test and it was found to be comparable to that of plasma-sprayed coatings

  11. Removal of organics and degradation products from industrial wastewater by a membrane bioreactor integrated with ozone or UV/H₂O₂ treatment.

    Science.gov (United States)

    Laera, G; Cassano, D; Lopez, A; Pinto, A; Pollice, A; Ricco, G; Mascolo, G

    2012-01-17

    The treatment of a pharmaceutical wastewater resulting from the production of an antibacterial drug (nalidixic acid) was investigated employing a membrane bioreactor (MBR) integrated with either ozonation or UV/H(2)O(2) process. This was achieved by placing chemical oxidation in the recirculation stream of the MBR. A conventional configuration with chemical oxidation as polishing for the MBR effluent was also tested as a reference. The synergistic effect of MBR when integrated with chemical oxidation was assessed by monitoring (i) the main wastewater characteristics, (ii) the concentration of nalidixic acid, (iii) the 48 organics identified in the raw wastewater and (iv) the 55 degradation products identified during wastewater treatment. Results showed that MBR integration with ozonation or UV/H(2)O(2) did not cause relevant drawbacks to both biological and filtration processes, with COD removal rates in the range 85-95%. Nalidixic acid passed undegraded through the MBR and was completely removed in the chemical oxidation step. Although the polishing configuration appeared to give better performances than the integrated system in removing 15 out of 48 secondary organics while similar removals were obtained for 19 other compounds. The benefit of the integrated system was however evident for the removal of the degradation products. Indeed, the integrated system allowed higher removals for 34 out of 55 degradation products while for only 4 compounds the polishing configuration gave better performance. Overall, results showed the effectiveness of the integrated treatment with both ozone and UV/H(2)O(2).

  12. Ozone/UV treatment to enhance biodegradation of surfactants in industrial wastewater. CRADA final report

    Energy Technology Data Exchange (ETDEWEB)

    Cline, J.E. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States); Sullivan, P.F. [Specialty Industrial Products, Inc., Spartanburg, SC (United States); Lovejoy, M.A.; Collier, J. [Sun River Innovations, Ltd., Lexington, KY (United States); Adams, C.D. [Univ. of Missouri, Rolla, MO (United States)

    1996-10-01

    The new owners of a surfactant manufacturing plant wanted to triple production but were limited by the plant`s wastewater treatment capacity. Mass balance calculations indicated that little aerobic biodegradation was occurring in the plant`s wastewater treatment system. Literature reviews and laboratory tests confirmed that as much as 60% of the plant`s products might resist aerobic biodegradation. Overall chemical losses, both solid and aqueous, were estimated at 3.8% of theoretical. Organic loadings to the wastewater treatment system were 170 kg/d of which 50 kg/d reached the biological treatment system. Pollution prevention measures have allowed a > 20% increase in production levels with a > 30% decrease in effluent volume and no increase in discharge of chemical oxygen demand (COD). A new dissolved air flotation (DAF) system removes 70% of the organic loading. Sludge volumes are lower by an order of magnitude than with the clarifier/drum-filter process it replaced.

  13. Modification of the optoelectronic properties of two-dimensional MoS2 crystals by ultraviolet-ozone treatment

    Science.gov (United States)

    Yang, Hae In; Park, Seonyoung; Choi, Woong

    2018-06-01

    We report the modification of the optoelectronic properties of mechanically-exfoliated single layer MoS2 by ultraviolet-ozone exposure. Photoluminescence emission of pristine MoS2 monotonically decreased and eventually quenched as ultraviolet-ozone exposure time increased from 0 to 10 min. The reduction of photoluminescence emission accompanied reduction of Raman modes, suggesting structural degradation in ultraviolet-ozone exposed MoS2. Analysis with X-ray photoelectron spectroscopy revealed that the formation of Ssbnd O and Mosbnd O bonding increases with ultraviolet-ozone exposure time. Measurement of electrical transport properties of MoS2 in a bottom-gate thin-film transistor configuration suggested the presence of insulating MoO3 after ultraviolet-ozone exposure. These results demonstrate that ultraviolet-ozone exposure can significantly influence the optoelectronic properties of single layer MoS2, providing important implications on the application of MoS2 and other two-dimensional materials into optoelectronic devices.

  14. Electron beam wastewater treatment in Brazil

    International Nuclear Information System (INIS)

    Sampa, M.H.O.; Rela, P.R.; Duarte, C.L.; Borrely, S.I.; Oikawa, H.; Somessari, E.S.R.; Silveira, C.G.; Costa, F.E.

    2001-01-01

    Experiments were performed at laboratory scale and at pilot plant scale to study the efficiency on using EB to remove and degrade toxic and refractory pollutants mainly from industrial origins. An upflow stream hydraulic system that governs the efficiency of the EB energy transferred to the stream was developed. Two different sources of samples were used to treat industrial effluents from a pharmaceutical chemical industry located in Sao Paulo and from a Governmental Wastewater Treatment Plant (WWTP) in Sao Paulo State, which receives the major quantity of industrial wastewater. Using samples from this WWTP, studies to combine EB irradiation process with conventional treatment were carried out with experimentation doses of 5 kGy, 10 kGy and 20 kGy and the irradiation effects were evaluated in the following parameters: COD, BOD, solids, TOC, THMs. PCE, TCE, BTX and concentration of organic acids by-products. Toxicity studies were also carried out for different sites and industrial activities showing significant removal of acute toxicity by increasing values of the EC-50 for most of the experiments. The economic aspects of this technology were evaluated and the estimated processing costs for some values of delivered doses and operation are reported here. (author)

  15. Electron beam collimation with a photon MLC for standard electron treatments

    Science.gov (United States)

    Mueller, S.; Fix, M. K.; Henzen, D.; Frei, D.; Frauchiger, D.; Loessl, K.; Stampanoni, M. F. M.; Manser, P.

    2018-01-01

    Standard electron treatments are currently still performed using standard or molded patient-specific cut-outs placed in the electron applicator. Replacing cut-outs and electron applicators with a photon multileaf collimator (pMLC) for electron beam collimation would make standard electron treatments more efficient and would facilitate advanced treatment techniques like modulated electron radiotherapy (MERT) and mixed beam radiotherapy (MBRT). In this work, a multiple source Monte Carlo beam model for pMLC shaped electron beams commissioned at a source-to-surface distance (SSD) of 70 cm is extended for SSDs of up to 100 cm and validated for several Varian treatment units with field sizes typically used for standard electron treatments. Measurements and dose calculations agree generally within 3% of the maximal dose or 2 mm distance to agreement. To evaluate the dosimetric consequences of using pMLC collimated electron beams for standard electron treatments, pMLC-based and cut-out-based treatment plans are created for a left and a right breast boost, a sternum, a testis and a parotid gland case. The treatment plans consist of a single electron field, either alone (1E) or in combination with two 3D conformal tangential photon fields (1E2X). For each case, a pMLC plan with similar treatment plan quality in terms of dose homogeneity to the target and absolute mean dose values to the organs at risk (OARs) compared to a cut-out plan is found. The absolute mean dose to an OAR is slightly increased for pMLC-based compared to cut-out-based 1E plans if the OAR is located laterally close to the target with respect to beam direction, or if a 6 MeV electron beam is used at an extended SSD. In conclusion, treatment plans using cut-out collimation can be replaced by plans of similar treatment plan quality using pMLC collimation with accurately calculated dose distributions.

  16. Physicochemical changes in minimal ozone-treated fresh shrimp ...

    African Journals Online (AJOL)

    treated fresh shrimp were evaluated tandem with microbiological efficacy of treatment during iced storage of up to 10 days. Safely discharged from commercially available domestic-type ozone facility, a previously defined minimal ozone treatment ...

  17. Discoloration and detoxicification of a Congo red dye solution by means of ozone treatment for a possible water reuse.

    Science.gov (United States)

    Khadhraoui, M; Trabelsi, H; Ksibi, M; Bouguerra, S; Elleuch, B

    2009-01-30

    The objective of this study was to investigate the degradation and mineralization of an azo-dye, the Congo red, in aqueous solutions using ozone. Phytotoxicity and the inhibitory effects on the microbial activity of the raw and the ozonated solutions were also carried out with the aim of water reuse and environment protection. Decolorization of the aqueous solutions, disappearance of the parent compound, chemical oxygen demand (COD) and total organic carbon (TOC) removal were the main parameters monitored in this study. To control the mineralization of the Congo red, pH of the ozonated solution and heteroatoms released from the mother molecule such NH(4)(+), NO(3)(-) and SO(4)(2-) were determined. It was concluded that ozone by itself is strong enough to decolorize these aqueous solutions in the early stage of the oxidation process. Nonetheless, efficient mineralization had not been achieved. Significant drops in COD (54%) were registered. The extent of TOC removal was about 32%. Sulfur heteroatom was totally oxidized to SO(4)(2-) ions while the central -NN- azo ring was partially converted to NH(4)(+) and NO(3)(-). Results of the kinetic studies showed that ozonation of the selected molecule was a pseudo-first-order reaction with respect to dye concentration. The obtained results also demonstrate that ozone process reduced the phytotoxicity of the raw solution and enhanced the biodegradability of the treated azo-dyes-wastewater. Hence, this show that ozone remains one of the effective technologies for the discoloration and the detoxification of organic dyes in wastewater.

  18. A hybrid process of biofiltration of secondary effluent followed by ozonation and short soil aquifer treatment for water reuse.

    Science.gov (United States)

    Zucker, I; Mamane, H; Cikurel, H; Jekel, M; Hübner, U; Avisar, D

    2015-11-01

    The Shafdan reclamation project facility (Tel Aviv, Israel) practices soil aquifer treatment (SAT) of secondary effluent with hydraulic retention times (HRTs) of a few months to a year for unrestricted agricultural irrigation. During the SAT, the high oxygen demand (>40 mg L(-1)) of the infiltrated effluent causes anoxic conditions and mobilization of dissolved manganese from the soil. An additional emerging problem is the occurrence of persistent trace organic compounds (TrOCs) in reclaimed water that should be removed prior to reuse. An innovative hybrid process based on biofiltration, ozonation and short SAT with ∼22 d HRT is proposed for treatment of the Shafdan secondary effluent to overcome limitations of the existing system and to reduce the SAT's physical footprint. Besides efficient removal of particulate matter to minimize clogging, coagulation/flocculation and filtration (5-6 m h(-1)) operated with the addition of hydrogen peroxide as an oxygen source efficiently removed dissolved organic carbon (DOC, to 17-22%), ammonium and nitrite. This resulted in reduced effluent oxygen demand during infiltration and oxidant (ozone) demand during ozonation by 23 mg L(-1) and 1.5 mg L(-1), respectively. Ozonation (1.0-1.2 mg O3 mg DOC(-1)) efficiently reduced concentrations of persistent TrOCs and supplied sufficient dissolved oxygen (>30 mg L(-1)) for fully oxic operation of the short SAT with negligible Mn(2+) mobilization (<50 μg L(-1)). Overall, the examined hybrid process provided DOC reduction of 88% to a value of 1.2 mg L(-1), similar to conventional SAT, while improving the removal of TrOCs and efficiently preventing manganese dissolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Electron-beam flue-gas treatment system

    International Nuclear Information System (INIS)

    Aoki, Sinji; Suzuki, Ryoji

    1994-01-01

    The damage of forests in the world due to acid rain has become serious problems, and the development of high efficiency and economical desulfurization and denitration technologies for combustion exhaust gas has been desired. Japan leads the world in exhaust gas treatment technology. The conventional technologies have been the desulfurization by lime gypsum process and the denitration by ammonia catalytic reduction process. The solution by entirely new concept is the electron beam treatment technology for exhaust gas. This technology is a dry process without drain, and does not require catalyst. The byproduct from this technology was approved as a fertilizer. The electron beam treatment technology is called EBA (electron beam with ammonia). The exhaust gas treatment technology by electron beam process is constituted by the cooling of exhaust gas, ammonia addition, electron beam irradiation and the separation of byproduct. The features of the technology are the simultaneous removal of sulfur and nitrogen oxides, dry process, the facilities are simple and the operation is easy, easy following to load variation and the utilization of byproduct. The reaction mechanism of desulfurization and denitration, the course of development, the electron beam generator, and the verifying test are reported. (K.I.)

  20. Electron treatment of wood pulp for the viscose process

    Science.gov (United States)

    Stepanik, T. M.; Ewing, D. E.; Whitehouse, R.

    2000-03-01

    Electron processing is currently being evaluated by several viscose producers for integration into their process. The viscose industry converts dissolving wood pulp into products such as staple fibre, filament, cord, film, packaging, and non-edible sausage casings. These materials are used in the clothing, drapery, hygiene, automobile, food, and packaging industries. Viscose producers are facing increasingly high production costs and stringent environmental regulations that have forced some plants to close. Electron treatment of wood pulp can significantly reduce the amounts of chemicals used for producing viscose and the production of hazardous pollutants. Acsion Industries has worked with companies worldwide to demonstrate the benefits of using electron treated pulp for producing viscose (rayon). This paper describes the viscose process, the benefits of using electron treatment in the viscose process, and Acsion's efforts in developing this technology.

  1. Development of electron beam flue gas treatment technology

    International Nuclear Information System (INIS)

    Tokunaga, Okihiro; Namba, Hideki; Tanaka, Tadashi; Ogura, Yoshimi; Doi, Yoshitake; Aoki, Shinji; Izutsu, Masahiro.

    1995-01-01

    Smoke treatment system making use of electron beam irradiation made it possible to simultaneously eliminate SOx and NOn from exhaust gas. The fundamental study of the system was started in the seventies and at present, its application in practical use is under way. A pilot plant for the smoke treatment system was constructed in cooperation of Chubu Electric Power Company, Inc., Japan Atomic Energy Research Institute and Ebara Corporation and several tests with the actual exhaust gas were conducted during the period, Oct. 1992-Dec. 1993 and the treatment efficiency and the control capacity of this system was confirmed to be so high as the conventional systems and many engineering data were obtained. A high treatment efficiency (>94% for desulfurization and >80% for denitrification) was obtainable by choosing the optimum irradiation amount of electron beam and the optimum temperature of gas to treat. And this system was found superior from a financial aspect to the conventional smoke treatment system. (M.N.)

  2. Treatment of basal cell epithelioma with high energy electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Y. (Hyogo-ken Cancer Center, Kobe (Japan)); Kumano, M.; Kumano, K.

    1981-11-01

    Thirty patients with basal cell epithelioma received high energy electron beam therapy. They were irradiated with a dose ranging from 4,800 rad (24 fractions, 35 days) to 12,000 rad (40 fractions, 57 days). Tumors disappeared in all cases. These were no disease-related deaths; in one patient there was recurrence after 2 years. We conclude that radiotherapy with high energy electron beam is very effective in the treatment of basal cell epithelioma.

  3. High power electron accelerators for flue gas treatment

    International Nuclear Information System (INIS)

    Zimek, Z.

    2011-01-01

    Flue gas treatment process based on electron beam application for SO 2 and NO x removal was successfully demonstrated in number of laboratories, pilot plants and industrial demonstration facilities. The industrial scale application of an electron beam process for flue gas treatment requires accelerators modules with a beam power 100-500 kW and electron energy range 0.8-1.5 MeV. The most important accelerator parameters for successful flue gas radiation technology implementation are related to accelerator reliability/availability, electrical efficiency and accelerator price. Experience gained in high power accelerators exploitation in flue gas treatment industrial demonstration facility was described and high power accelerator constructions have been reviewed. (author)

  4. High power electron accelerators for flue gas treatment

    Energy Technology Data Exchange (ETDEWEB)

    Zimek, Z. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

    2011-07-01

    Flue gas treatment process based on electron beam application for SO{sub 2} and NO{sub x} removal was successfully demonstrated in number of laboratories, pilot plants and industrial demonstration facilities. The industrial scale application of an electron beam process for flue gas treatment requires accelerators modules with a beam power 100-500 kW and electron energy range 0.8-1.5 MeV. The most important accelerator parameters for successful flue gas radiation technology implementation are related to accelerator reliability/availability, electrical efficiency and accelerator price. Experience gained in high power accelerators exploitation in flue gas treatment industrial demonstration facility was described and high power accelerator constructions have been reviewed. (author)

  5. Oxidative treatment of a waste water stream from a molasses processing using ozone and advanced oxidation technologies

    International Nuclear Information System (INIS)

    Gehringer, P.; Szinovatz, W.; Eschweiler, H.; Haberl, R.

    1994-08-01

    The discoloration of a biologically pretreated waste water stream from a molasses processing by ozonation and two advanced oxidation processes (O 3 /H 2 O 2 and O 3 /γ-irradiation, respectively) was studied. Colour removal occurred with all three processes with almost the same efficiency. The main difference of the methods applied was reflected by the BOD increase during the discoloration period. By ozonation it was much higher than by AOPs but it also appeared with AOPs. AOPs were, therefore, not apt for an effective BOD control during discoloration. (authors)

  6. Microcystis aeruginosa-laden water treatment using enhanced coagulation by persulfate/Fe(II), ozone and permanganate: Comparison of the simultaneous and successive oxidant dosing strategy.

    Science.gov (United States)

    Liu, Bin; Qu, Fangshu; Chen, Wei; Liang, Heng; Wang, Tianyu; Cheng, Xiaoxiang; Yu, Huarong; Li, Guibai; Van der Bruggen, Bart

    2017-11-15

    In this study, the application of enhanced coagulation with persulfate/Fe(II), permanganate and ozone for Microcystis-laden water treatment was investigated. Two oxidant dosage strategies were compared in terms of the organic removal performance: a simultaneous dosing strategy (SiDS) and a successive dosing strategy (SuDS). To optimize the oxidant species, oxidant doses and oxidant dosage strategy, the zeta potential, floc size and dimension fraction, potassium release and organic removal efficiency during the coagulation of algae-laden water were systematically investigated and comprehensively discussed. Ozonation causes most severe cell lysis and reduces organic removal efficiency because it releases intracellular organics. Moreover, ozonation can cause the release of odor compounds such as 2-methylisoborneol (2-MIB) and geosmin (GSM). With increasing doses, the performance of pollutant removal by coagulation enhanced by persulfate/Fe(II) or permanganate did not noticeably improve, which suggests that a low dosage of persulfate/Fe(II) and permanganate is the optimal strategy to enhance coagulation of Microcystis-laden water. The SiDS performs better than the SuDS because more Microcystis cell lysis occurs and less DOC is removed when oxidants are added before the coagulants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Impact of diatomite on the slightly polluted algae-containing raw water treatment process using ozone oxidation coupled with polyaluminum chloride coagulation.

    Science.gov (United States)

    Hu, Wenchao; Wu, Chunde; Jia, Aiyin; Zhang, Zhilin; Chen, Fang

    2014-01-01

    The impact of adding diatomite on the treatment performance of slightly polluted algae-containing raw water using ozone pre-oxidation and polyaluminum chloride (PAC) coagulation was investigated. Results demonstrated that the addition of diatomite is advantageous due to reduction of the PAC dose (58.33%) and improvement of the removal efficiency of algae, turbidity, and dissolved organic matter (DOM) in raw water. When the ozone concentration was 1.0 mg L⁻¹ and the PAC dosage was 2.5 mg L⁻¹, the removal rates of algae, turbidity, UV254, and TOC were improved by 6.39%, 7.06%, 6.76%, and 4.03%, respectively, with the addition of 0.4 g L⁻¹ diatomite. It has been found that the DOM presented in the Pearl River raw water mainly consisted of small molecules ( 50 kDa). After adding diatomite (0.4 g L⁻¹), the additional removal of 5.77% TOC and 14.82% UV254 for small molecules (50 kDa) could be achieved, respectively, at an ozone concentration of 1.0 mg L⁻¹ and a PAC dose of 2.5 mg L⁻¹. The growth of anabaena flos-aquae (A.F.) was observed by an atomic force microscope (AFM) before and after adding diatomite. AFM images demonstrate that diatomite may have a certain adsorption on A.F.

  8. The treatment of lumbar disc herniation: a comparison between percutaneous lumbar diskectomy combined with ozone and percutaneous lumbar diskectomy combined with collagenase

    International Nuclear Information System (INIS)

    Zhong Liming; Wei Xin; Hu Hong; You Jian; Zhao Xiaowei; Hu Kongqiong

    2012-01-01

    Objective: To evaluate the short-term curative effect and the incidence of postoperative adverse events of percutaneous lumbar diskectomy (PLD) combined with ozone or PLD combined with collagenase in treating lumbar disk herniation. Methods: A total of 223 patients with lumbar disk herniation were enrolled in this study. Patients in the study group (n=108) were treated with PLD combined with ozone, while patients in the control group (n=115) were treated with PLD combined with collagenase. The short-term effectiveness and the incidence of postoperative adverse events were documented. The results were analyzed and compared between the two groups. Results: In the study group, the excellent and good therapeutic results were achieved in 85.18% of the patients (n=92) and the occurrence of adverse events was 5.56%, while in the control group, the excellent and good therapeutic results were achieved in 80.00% of the patients (n=92) and the occurrence of adverse events was 13.04%. No significant difference in the short-term effectiveness existed between the two groups (Pearson Chi-Square =1.038, P=0.308). And the difference in the occurrence of postoperative adverse events was not significant between the two groups (Pearson Chi-Square =3.661, P=0.056). No disc infection occurred in the study group. Conclusion: The short-term curative effect of PLD combined with ozone is not significantly different from that of PLD combined with collagenase. In order to maintain decompression within the disc for a long period and to reduce the incidence of postoperative adverse events PLD combined with ozone ablation is an effective complementary treatment. (authors)

  9. Bench scale studies: Ozonation as a potential treatment for waters contaminated with hydrocarbons or dioxins and furans

    International Nuclear Information System (INIS)

    Schaal, W.

    1995-01-01

    The objective of the bench scale studies was to examine the destruction efficiency and efficacy of ozone on chemicals of concern (COC's) commonly found in contaminated ground water and rhenoformer wash water. The ground water used in these tests contained aromatic petroleum hydrocarbons, chlorinated hydrocarbons, and mineral spirits. The rhenoformer wash water used in these tests contained a variety of dioxins (including 2,3,7,8-tetrachlorodibenzo-p-dioxin) and furans. Summaries are presented of the bench scale studies by describing the COCs, methodologies, test reactors, observations, and results. The summaries also detail which applications hold promise with respect to ozonation and which ones do not. Bench test results for the experiments in which aromatic petroleum hydrocarbons, chlorinated hydrocarbons, and mineral spirits where the COCs were relatively successful. Concentrations for the COCs ranging from 300 to 3,400 micrograms per liter (microg/L) were brought below levels specified for storm sewer discharge per the National Priority Discharge Elimination Systems (NPDES) permit requirements. Bench test results for the experiments in which dioxins and furans were the COCs were less promising and revealed that additional processes would have to be used in conjunction with ozonation to bring the concentration of COCs within the targeted ranges. It was realized, however, that the effectiveness and efficacy of ozonation were diminished by the presence of particulates, to which some of the dioxin and furan compounds adhered

  10. "OZONE SOURCE APPORTIONMENT IN CMAQ' | Science ...

    Science.gov (United States)

    Ozone source attribution has been used to support various policy purposes including interstate transport (Cross State Air Pollution Rule) by U.S. EPA and ozone nonattainment area designations by State agencies. Common scientific applications include tracking intercontinental transport of ozone and ozone precursors and delineating anthropogenic and non-anthropogenic contribution to ozone in North America. As in the public release due in September 2013, CMAQ’s Integrated Source Apportionment Method (ISAM) attributes PM EC/OC, sulfate, nitrate, ammonium, ozone and its precursors NOx and VOC, to sectors/regions of users’ interest. Although the peroxide-to-nitric acid productions ratio has been the most common indicator to distinguish NOx-limited ozone production from VOC-limited one, other indicators are implemented in addition to allowing for an ensemble decision based on a total of 9 available indicator ratios. Moreover, an alternative approach of ozone attribution based on the idea of chemical sensitivity in a linearized system that has formed the basis of chemical treatment in forward DDM/backward adjoint tools has been implemented in CMAQ. This method does not require categorization into either ozone regime. In this study, ISAM will simulate the 2010 North America ozone using all of the above gas-phase attribution methods. The results are to be compared with zero-out difference out of those sectors in the host model runs. In addition, ozone contribution wil

  11. Pilot test of flue gas treatment by electron beam

    International Nuclear Information System (INIS)

    Tokunaga, Okihiro

    1995-01-01

    The development of the technology of the desulfurization and denitration for flue gas by using electron beam was started in Japan in 1970s, and since then, the development research for putting it to practical use and the basic research on the subjects which must be resolved for promoting the practical use have been advanced. Based on these results, the verifying test using a pilot scale plant was carried out from 1991 to 1994 for the treatment of coal-burning flue gas, municipal waste-burning flue gas and highway tunnel exhaust gas. The operation of the pilot plant was already finished, and the conceptual design of a practical scale plant based on the results and the assessment of the economical efficiency were performed. As for the coal-burning flue gas treatment by using electron beam, the basic test, the pilot test and the conceptual design of a practical scale plant and the assessment of the economical efficiency are reported. As for the municipal waste-burning flue gas treatment by using electron beam, the basic test and the pilot test are reported. Also the pilot test on the denitration of exhaust gas in highway tunnels in reported. In Poland, the pilot test on the treatment of flue gas in coal-burning thermal power stations is carried out. In Germany, the technical development for cleaning the air contaminated by volatile organic compounds by electron beam irradiation is advanced. (K.I.)

  12. The effect of ozone and open air factor on surface-attached and biofilm environmental Listeria monocytogenes.

    Science.gov (United States)

    Nicholas, R; Dunton, P; Tatham, A; Fielding, L

    2013-08-01

    The effects of gaseous ozone and open air factor (OAF) on environmental Listeria monocytogenes attached to three common food contact surfaces were investigated. Listeria monocytogenes on different food contact surfaces was treated with ozone and OAF. Microbiological counts, scanning electron microscopy (SEM) and atomic force microscopy (AFM) were performed. Ozone at 10 ppm gave <1-log reduction when L. monocytogenes was attached to stainless steel, while 45 ppm gave a log reduction of 3.41. OAF gave better log reductions than 10 ppm ozone, but lower log reductions than 45 ppm. Significant differences were found between surfaces. Biofilm organisms were significantly more resistant than those surface attached on stainless steel. SEM and AFM demonstrated different membrane and cell surface modifications following ozone or OAF treatment. The strain used demonstrated higher resistance to ozone than previous studies. This may be due to the fact that it was isolated from a food manufacturing premises that used oxidizing disinfectants. OAF was more effective at reducing the levels of the organism than an ozone concentration of 10 ppm. Pathogen management strategies must account for resistance of environmental strains when validating cleaning and disinfection. OAF has shown potential for surface decontamination compared with ozone. SEM and AFM are valuable tools for determining mechanisms of action of antimicrobial agents. © 2013 The Society for Applied Microbiology.

  13. Ozone Layer Protection

    Science.gov (United States)

    ... and Research Centers Contact Us Share Ozone Layer Protection The stratospheric ozone layer is Earth’s “sunscreen” – protecting ... GreenChill Partnership Responsible Appliance Disposal (RAD) Program Ozone Protection vs. Ozone Pollution This website addresses stratospheric ozone ...

  14. Influence of post-deposition treatment by UV light and oxygen (ozone) on 350 nm damage thresholds of SiO2 films deposited from sols

    International Nuclear Information System (INIS)

    Thomas, I.; Wilder, J.; Lee, A.; George, D.

    1988-01-01

    Certain multilayer porous silica AR coatings on fused silica substrates prepared by the sol-gel process have been found to have a much lower laser damage threshold than single layer coatings prepared by the same method. Treatment with UV light in the presence of oxygen (which gives ozone) at low temperature was found to restore damage thresholds to the levels found in single layers. Damage thresholds were measured at 350 nm with a 25 ns pulse for 1000 shots at 25 Hz. The effect of exposure time and other factors such as replacement of oxygen with nitrogen and vacuum are described

  15. Effect of pentacene/Ag anode buffer and UV-ozone treatment on durability of small-molecule organic solar cells

    International Nuclear Information System (INIS)

    Inagaki, S; Sueoka, S; Harafuji, K

    2017-01-01

    Three surface modifications of indium tin oxide (ITO) are experimentally investigated to improve the performance of small-molecule organic solar cells (OSCs) with an ITO/anode buffer layer (ABL)/copper phthalocyanine (CuPc)/fullerene/bathocuproine/Ag structure. An ultrathin Ag ABL and ultraviolet (UV)-ozone treatment of ITO independently improve the durability of OSCs against illumination stress. The thin pentacene ABL provides good ohmic contact between the ITO and the CuPc layer, thereby producing a large short-circuit current. The combined use of the abovementioned three modifications collectively achieves both better initial performance and durability against illumination stress. (paper)

  16. Effect of pentacene/Ag anode buffer and UV-ozone treatment on durability of small-molecule organic solar cells

    Science.gov (United States)

    Inagaki, S.; Sueoka, S.; Harafuji, K.

    2017-06-01

    Three surface modifications of indium tin oxide (ITO) are experimentally investigated to improve the performance of small-molecule organic solar cells (OSCs) with an ITO/anode buffer layer (ABL)/copper phthalocyanine (CuPc)/fullerene/bathocuproine/Ag structure. An ultrathin Ag ABL and ultraviolet (UV)-ozone treatment of ITO independently improve the durability of OSCs against illumination stress. The thin pentacene ABL provides good ohmic contact between the ITO and the CuPc layer, thereby producing a large short-circuit current. The combined use of the abovementioned three modifications collectively achieves both better initial performance and durability against illumination stress.

  17. Ozonation of estrogenic chemicals in biologically treated sewage

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Andersen, Henrik Rasmus; Ledin, Anna

    2010-01-01

    The present study shows that ozonation of effluents from municipal wastewater treatment plants (WWTPs) is likely to be a future treatment solution to remove estrogens and xeno-estrogens. The required ozone dose and electrical energy for producing the ozone were determined in two WWTP effluents fo...

  18. Ozone kinetics in low-pressure discharges

    Science.gov (United States)

    Guerra, Vasco; Marinov, Daniil; Guaitella, Olivier; Rousseau, Antoine

    2012-10-01

    Ozone kinetics is quite well established at atmospheric pressure, due to the importance of ozone in atmospheric chemistry and to the development of industrial ozone reactors. However, as the pressure is decreased and the dominant three-body reactions lose importance, the main mechanisms involved in the creation and destruction of ozone are still surrounded by important uncertainties. In this work we develop a self-consistent model for a pulsed discharge and its afterglow operating in a Pyrex reactor with inner radius 1 cm, at pressures in the range 1-5 Torr and discharge currents of 40-120 mA. The model couples the electron Boltzmann equation with a system of equations for the time evolution of the heavy particles. The calculations are compared with time-dependent measurements of ozone and atomic oxygen. Parametric studies are performed in order to clarify the role of vibrationally excited ozone in the overall kinetics and to establish the conditions where ozone production on the surface may become important. It is shown that vibrationally excited ozone does play a significant role, by increasing the time constants of ozone formation. Moreover, an upper limit for the ozone formation at the wall in these conditions is set at 10(-4).

  19. Removal of pharmaceuticals in WWTP effluents by ozone and ...

    African Journals Online (AJOL)

    2013-02-12

    Feb 12, 2013 ... discharge of effluents by wastewater treatment plants (WWTPs) that are not ... The efficiency of ozone in removing pharmaceuticals and personal care ...... assessment and modeling of an ozonation step for full-scale munic-.

  20. Electron Beam Treatment Plant for Textile Dyeing Wastewater

    International Nuclear Information System (INIS)

    Han, Bumsoo; Kim, Yuri; Choi, Jangseung; Ahn, Sangjun

    2006-01-01

    High positive effect of electron-beam treatment involved into the process of wastewater purification is now well established. The most effective for the purpose seem to be combine methods including both electron beam and any conventional treatment stages, i.e., under conditions when some synergistic effects can take place. Daegu Dyeing Industrial Complex (DDIC) includes about hundred factories occupying the area of 600,000m 2 with 13,000 employees in total. The production requires high consumption of water (90,000m 3 /day), steam, and electric power, being characterized by large amount of highly colored industrial wastewater. Because of increase in productivity and increased assortment of dyes and other chemicals, substantial necessity appears in re-equipment of purification facilities by application of efficient methods of wastewater treatment

  1. Removal of dissolved organic matter in municipal effluent with ozonation, slow sand filtration and nanofiltration as high quality pre-treatment option for artificial groundwater recharge.

    Science.gov (United States)

    Linlin, Wu; Xuan, Zhao; Meng, Zhang

    2011-04-01

    In the paper the combination process of ozonation, slow sand filtration (SSF) and nanofiltration (NF) was investigated with respect to dissolved organic matter (DOM) removal as high quality pre-treatment option for artificial groundwater recharge. With the help of ozonation leading to breakdown of the large organic molecules, SSF preferentially removes soluble microbial by-product-like substances and DOM with molecular weight (MW) less than 1.0 kDa. NF, however, removes aromatic, humic acid-like and fulvic acid-like substances efficiently and specially removes DOM with MW above 1.0 kDa. The residual DOM of the membrane permeate is dominated by small organics with MW 500 Da, which can be further reduced by the aquifer treatment, despite of the very low concentration. Consequently, the O(3)/SSF/NF system offers a complementary process in DOM removal. Dissolved organic carbon (DOC) and trihalomethane formation potential (THMFP) can be reduced from 6.5±1.1 to 0.7±0.3 mg L(-1) and from 267±24 to 52±6 μg L(-1), respectively. The very low DOC concentration of 0.6±0.2 mg L(-1) and THMFP of 44±4 μg L(-1) can be reached after the aquifer treatment. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Model of daytime emissions of electronically-vibrationally excited products of O3 and O2 photolysis: application to ozone retrieval

    Directory of Open Access Journals (Sweden)

    V. A. Yankovsky

    2006-11-01

    Full Text Available The traditional kinetics of electronically excited products of O3 and O2 photolysis is supplemented with the processes of the energy transfer between electronically-vibrationally excited levels O2(a1Δg, v and O2(b1Σ+g, v, excited atomic oxygen O(1D, and the O2 molecules in the ground electronic state O2(X3Σg−, v. In contrast to the previous models of kinetics of O2(a1Δg and O2 (b1Σ+g, our model takes into consideration the following basic facts: first, photolysis of O3 and O2 and the processes of energy exchange between the metastable products of photolysis involve generation of oxygen molecules on highly excited vibrational levels in all considered electronic states – b1Σ+g, a1Δg and X3Σg−; second, the absorption of solar radiation not only leads to populating the electronic states on vibrational levels with vibrational quantum number v equal to 0 – O2(b1Σ+g, v=0 (at 762 nm and O2(a1Δg, v=0 (at 1.27 µm, but also leads to populating the excited electronic–vibrational states O2(b1Σ+g, v=1 and O2(b1Σ+g, v=2 (at 689 nm and 629 nm. The proposed model allows one to calculate not only the vertical profiles of the O2(a1Δg, v=0 and O2(b1Σg, v=0 concentrations, but also the profiles of [O2(a1Δg, v≤5], [O2 (b1Σ+g , v=1, 2] and O2(X3Σg−, v=1–35. In the altitude range 60–125 km, consideration of the electronic-vibrational kinetics significantly changes the calculated concentrations of the metastable oxygen molecules and reduces the discrepancy between the altitude profiles of ozone concentrations retrieved from the 762-nm and 1.27-µm emissions measured simultaneously.

  3. Film dosimetry of small elongated electron beams for treatment planning

    International Nuclear Information System (INIS)

    Niroomand-Rad, A.

    1989-01-01

    The characteristics of 5, 7, 10, 12, 15, and 18 Mev electron beams for small elongated fields of dimensions L x W (where L=1, 2, 3, 4, 5, and 10 cm; and W=1, 2, 3, 4, 5, and 10 cm) have been studied. Film dosimetry and parallel-plate ion chamber measurements have been used to obtain various dose parameters. Selective results of a series of systematic measurements for central axis depth dose data, uniformity index, field flatness, and relative output factors of small elongated electron beams are reported. The square-root method is employed to predict the beam data of small elongated electron fields from corresponding small square electron fields using film dosimetry. The single parameter area/perimeter radio A/P is used to characterize the relative output factors of elongated electron beams. It is our conclusion that for clinical treatment planning square-root method may be applied with caution in determining the beam characteristics of small elongated electron fields from film dosimetry. The calculated and estimated relative output factors from square-root method and A/P ratio are in good agreement and show agreement to within 1% with the measured film values

  4. Treatment Of Wastewater For Reuse With Mobile Electron Beam Plant

    International Nuclear Information System (INIS)

    Han, B.; Kim, J.K.; Kim, Y.R.; Zommer, N.

    2012-01-01

    The use of alternative disinfectants to chlorine for the wastewater treatment has received increasing attention in recent years to treat either liquid or solids streams within wastewater treatment plants for pathogens and trace organics (TOrCs). Although several technologies have come to the forefront as an alternative to chlorine (e.g., ultraviolet [UV] and hydrogen peroxide), the majority of these technologies are chemically based, with the exception of UV. An attractive physical disinfection approach is by electron beam (EB) irradiation. EB treatment of wastewater leads to their purification from various pollutants. It is caused by the decomposition of pollutants as a result of their reactions with highly reactive species formed from water radiolysis: hydrated electron, OH free radical and H atom [Pikaev (1986)]. Sometimes methods such as EB with biological treatment, adsorption and others improve the effect of EB treatment of the wastewater purification. In the process of EB treatment of wastewater there are utilized chemical transformations of pollutants induced by ionizing radiation. At sufficiently high absorbed doses these transformations can result in complete decomposition (removal) of the substance. Under real conditions, i.e., at rather high content of pollutants in a wastewater and economically acceptable doses, partial decomposition of pollutant takes place as well as transformations of pollutant molecules that result in improving subsequent purification stages, efficiency of the process being notably influenced by irradiation conditions and wastewater composition [Woods and Pikaev (1994)]. (author)

  5. Treatment Of Wastewater For Reuse With Mobile Electron Beam Plant

    Energy Technology Data Exchange (ETDEWEB)

    Han, B.; Kim, J. K.; Kim, Y. R. [EB TECH Co., Ltd., Daejeon (Korea, Republic of); Zommer, N. [Pele Inc., Milpitas Californaa (United States)

    2012-07-01

    The use of alternative disinfectants to chlorine for the wastewater treatment has received increasing attention in recent years to treat either liquid or solids streams within wastewater treatment plants for pathogens and trace organics (TOrCs). Although several technologies have come to the forefront as an alternative to chlorine (e.g., ultraviolet [UV] and hydrogen peroxide), the majority of these technologies are chemically based, with the exception of UV. An attractive physical disinfection approach is by electron beam (EB) irradiation. EB treatment of wastewater leads to their purification from various pollutants. It is caused by the decomposition of pollutants as a result of their reactions with highly reactive species formed from water radiolysis: hydrated electron, OH free radical and H atom [Pikaev (1986)]. Sometimes methods such as EB with biological treatment, adsorption and others improve the effect of EB treatment of the wastewater purification. In the process of EB treatment of wastewater there are utilized chemical transformations of pollutants induced by ionizing radiation. At sufficiently high absorbed doses these transformations can result in complete decomposition (removal) of the substance. Under real conditions, i.e., at rather high content of pollutants in a wastewater and economically acceptable doses, partial decomposition of pollutant takes place as well as transformations of pollutant molecules that result in improving subsequent purification stages, efficiency of the process being notably influenced by irradiation conditions and wastewater composition [Woods and Pikaev (1994)]. (author)

  6. Treatment of breast cancer recurrence with fast electrons

    Energy Technology Data Exchange (ETDEWEB)

    Gremilov, V A; Svistunova, T M; Migmanova, N Sh [Akademiya Meditsinskikh Nauk SSSR, Leningrad. Inst. Onkologii

    1978-01-01

    Feasibility of treating mammary gland cancer recurrences by means of fast electron is investigated. Local recurrences and metastases were inradiated with 10 MeV fast electrons, and regional ones - with 15 MeV fast electrons. The irradiation technique used permitted the occurence of early and late local radiation responses as well as complications to be avoided. The treatment effect resulted from a value, form and clinical course of recurrence, as well as from cumulative dose with optimum value of 5000-6000 rad. The direct and nearest treatment results in respect of local criterion of the effect are recognized as satisfactory. Taking into consideration, that local and regional recurrences and metastases in the most part of patients are the beginning of clinical manifestation of tumor process generalization, it is assumed, that local treatment of local and regional recurrences and metastases of mammary gland cancer is not reliable therapeutic measure and must be combined with general treatment (chemo- and hormonotherapy) and specific measures enhancing the total resistance of the body.

  7. Application of electron beam irradiation. 4. Treatment of pollutants by electron beam irradiation

    International Nuclear Information System (INIS)

    Tokunaga, Okihiro; Arai, Hidehiko

    1994-01-01

    Electron beam irradiation is capable of dissolving and removing pollutants, such as sulfur oxides, nitrogen oxides, and organic compounds, by easy production of OH radicals in flue gas and water. This paper deals with current status in the search for techniques for treating flue gas and waste water, using electron beam irradiation. Pilot tests have been conducted during the period 1991-1994 for the treatment of flue gas caused by coal and garbage burning and road tunnels. Firstly, techniques for cleaning flue gas with electron beams are outlined, with special reference to their characteristics and process of research development. Secondly, the application of electron beam irradiation in the treatment of waste water is described in terms of the following: (1) disinfection of sewage, (2) cleaning of water polluted with toxic organic compounds, (3) treatment for eliminating sewage sludge, (4) promotion of sewage sludge sedimentation, (5) disinfection and composting of sewage sludge, and (6) regeneration of activated carbon used for the treatment of waste water. (N.K.)

  8. Electronic compliance monitoring of topical treatment after ophthalmic surgery.

    Science.gov (United States)

    Hermann, Manuel Marcel; Ustündag, Can; Diestelhorst, Michael

    2010-08-01

    The success of many medical treatments is built on compliance. Electronic monitoring is the most accurate tool to quantify compliance by measuring adherence. In order to assess the efficiency of a recently introduced miniature monitoring device for eye drop application, we evaluated adherence in ophthalmic patients undergoing post-operative short-term topical treatment. This pilot study enrolled 30 outpatients (mean age 61.8 +/- 18.5 years) after cataract (n = 24) and glaucoma filtration surgery (n = 6) applying fixed-combination eye drops containing prednisolone and gentamicin five times daily for 2 weeks. Patients received eye drops in conventional bottles each equipped with a miniature monitoring device recording events of application. Two patients failed to bring back the monitoring device; therefore data collected from only 28 patients could be examined. Data showed highly variable results with a mean dose compliance of 50.2%. Dose compliance was below 25% in approximately one out of five patients. Four cataract patients, but no glaucoma patient, discontinued therapy prematurely. The observed mean dosage interval was calculated for each patient and ranged 4.6-19.7 h. Thirty percent of analysed dosage intervals exceeded 12.0 h. Different patterns of compliance behaviour-like early non-persistence, drug holiday and low treatment frequency could be identified and illustrated using electronic data. Age or gender did not significantly influence compliance rates. Our pilot study demonstrates successful electronic compliance monitoring using a technology capable of continuous data recording over weeks of treatment. The low compliance rate for a relevant part of the patients demonstrates the necessity to study and improve compliance in ophthalmology. In future, new application methods and electronic application devices may improve treatment response in eye care.

  9. Influence of ozone on RNA and protein content of Lemna minor L

    Energy Technology Data Exchange (ETDEWEB)

    Craker, L E

    1972-01-01

    The amount of RNA and protein in Lemna minor L. plants decreased after exposure to ozone, as compared with control plants receiving no ozone treatment. Differences in RNA and protein content between control and ozone-treated Lemna plants were detectable immediately following ozone treatments and remained throughout the 24 h sampling time.

  10. Electron beam treatment of toxic volatile organic compounds and dioxins

    International Nuclear Information System (INIS)

    Kojima, Takuji

    2006-01-01

    Considerations of wastes based on the reduction, reuse and recycle in daily life are primary measures to conserve our environment, but the control technology is necessary to support these measures. The electron beam (EB) process is promising as an advanced purification process having advantages such as a quick treatment of big volume gas, applicability even for very low concentration pollutants as the further purification at the downstream of existing process, and decomposition of pollutants into non-toxic substances by one process. The EB technology has been developed for treatment of toxic volatile organic compounds (VOCs) in ventilation gas and dioxins in solid waste incineration flue gas. (author)

  11. Waste treatment by microwave and electron beam irradiation

    International Nuclear Information System (INIS)

    Martin, D.; Craciun, G.; Manaila, E.; Ighigeanu, D; Oproiu, C.; Iacob, N.; Togoe, I.; Margaritescu, I.

    2007-01-01

    Comparative results obtained by applying separate and combined (successive and simultaneous) electron beam (EB) and microwave (MW) irradiation to waste treatment, such as food residuals (minced beef, wheat bran and wheat flour) and sewage sludge performed from a food industry wastewater treatment station (vegetable oil plant), are presented. The research results demonstrated that the simultaneous EB and MW irradiation produces the biggest reduction of microorganisms. The tests also demonstrated that the irradiation time and the upper limit of required EB absorbed dose, which ensures a complete sterilization effect, could be reduced by a factor of two by an additional use of MW energy to EB irradiation

  12. Clinical considerations of Monte Carlo for electron radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Faddegon, Bruce; Balogh, Judith; Mackenzie, Robert; Scora, Daryl

    1998-01-01

    Technical requirements for Monte Carlo based electron radiotherapy treatment planning are outlined. The targeted overall accuracy for estimate of the delivered dose is the least restrictive of 5% in dose, 5 mm in isodose position. A system based on EGS4 and capable of achieving this accuracy is described. Experience gained in system design and commissioning is summarized. The key obstacle to widespread clinical use of Monte Carlo is lack of clinically acceptable measurement based methodology for accurate commissioning

  13. Electron beam treatment removes both sulphur and nitrogen oxides

    International Nuclear Information System (INIS)

    Kawamura, K.; Miller, G.A.

    1985-01-01

    The Ebara Corporation in Japan has developed an electron beam flue gas treatment (e-beam fgt) process. The process offers the following features: simultaneous removal of SO 2 and NOsub(x); a dry process which involves no slurry recycling, no sludge disposal, and no gas reheating; turndown and load following capabilities with a minimum of process control; SO 2 and NOsub(x) are converted into saleable fertiliser. The demonstration plant is described. (author)

  14. Development of electron beam flue gas treatment technology

    International Nuclear Information System (INIS)

    Tanaka, T.

    1995-01-01

    The electron beam flue gas treatment technology is expected to bring many advantages such as the simultaneous reduction of SO x and NO x emissions, a dry process without waste water, valuable fertilizer byproducts, etc. In order to verify the feasibility and performances of the process, a practical application test is carried out with a pilot plant which treats the actual flue gas from a coal-fired boiler. Results are presented. 4 figs., 2 tabs

  15. ADVANCED OXIDATION PROCESS TECHNOLOGY (ULTRAVIOLET RADIATION/OZONE TREATMENT) FOR REMOVAL OF METHYL TERTIARY BUTYL ETHER (MTBE) IN GROUND WATER SUPPLIES.

    Science.gov (United States)

    U.S. EPA’s Office of Research and Development in Cincinnati, Ohio has been testing and evaluating MTBE removal in dechlorinated tap water using three oxidant combinations: hydrogen peroxide/ozone, ultraviolet irradiation (UV)/ozone, and UV/ozone/hydrogen peroxide. Pilot-scale st...

  16. Chromosome breakage in Vicia faba by ozone

    Energy Technology Data Exchange (ETDEWEB)

    Fetner, R H

    1958-02-15

    Meristem cells of Vicia faba roots were exposed to an atmosphere of ozone and the fraction of cells showing chromosome aberrations were recorded. Chromosome aberrations were observed on a dose-response basis after exposing the seeds to 0.4 wt. percent ozone for 15, 30, and 60 minutes. The results of ozone, x-rays, and ozone and x-ray treatments are presented. A small number of root tips from each group was treated with colchicine and an analysis made of metaphase aberrations. These observations confirmed that the aberrations were all of the chromosome-type.

  17. 21 CFR 173.368 - Ozone.

    Science.gov (United States)

    2010-04-01

    ... CONSUMPTION (CONTINUED) SECONDARY DIRECT FOOD ADDITIVES PERMITTED IN FOOD FOR HUMAN CONSUMPTION Specific Usage Additives § 173.368 Ozone. Ozone (CAS Reg. No. 10028-15-6) may be safely used in the treatment, storage, and processing of foods, including meat and poultry (unless such use is precluded by standards of identity in 9...

  18. 21 CFR 184.1563 - Ozone.

    Science.gov (United States)

    2010-04-01

    ...: Category of food Maximum treatment level in food Functional use Bottled water that prior to ozonation meets... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ozone. 184.1563 Section 184.1563 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN...

  19. CT-guided ozone/steroid therapy for the treatment of degenerative spinal disease - effect of age, gender, disc pathology and multi-segmental changes

    Energy Technology Data Exchange (ETDEWEB)

    Oder, Bernhard; Loewe, Maria; Reisegger, Michael; Thurnher, Siegfried A. [Hospital Brothers of St. John of God, Department of Radiology and Nuclear Medicine, Vienna (Austria); Lang, Wilfried [Hospital Brothers of St. John of God, Department of Neurology, Vienna (Austria); Ilias, Wilfried [Hospital Brothers of St. John of God, Department of Anaesthesiology, Intensive Care Medicine and Pain Therapy, Vienna (Austria)

    2008-09-15

    Oxygen-ozone nucleolysis (ONL) is a new, minimally invasive procedure for the treatment of discogenic low back pain with or without radicular symptoms. The aim of the present study was to determine associations between the morphology of the basic disease, patient-specific factors and the outcome of the treatment. Six hundred and twelve patients not responding to conservative therapy were divided into five groups (disc bulging, disc herniation, postoperative patients, osteochondrosis, others) and subjected to nucleolysis with ozone and to periradicular infiltration with steroids and local anaesthesia. The success of treatment was assessed by means of a visual analog pain scale (VAS) and the Oswestry Disability Index (ODI). A significant reduction in the VAS was registered after 2 and 6 months (from 8.6 to 5.4 and 6.0; p<0.001) in all patient groups; an excellent therapy response (VAS below 3.0) was achieved by about a third of the patients. A significant improvement in ODI was registered in all patients (46 to 31; p<0.001), most pronounced in the herniation group (25.5, p=0.015). Patients below 50 years had significantly better values in the VAS and ODI score 6 months after treatment. Final VAS and ODI scores for patients with a single diseased segment were 4.2 and 28.0, in two affected segments 6.5 and 32 and in three segments 6.7 and 38.5 (p<0.001 and p=0.051). ONL with periradicular steroid therapy might exert a functional and sustained analgesic effect in patients with degenerative changes in the lumbar spine not responding to conservative therapy and was most effective below 50 years with disc herniation in one segment. (orig.)

  20. CT-guided ozone/steroid therapy for the treatment of degenerative spinal disease - effect of age, gender, disc pathology and multi-segmental changes

    International Nuclear Information System (INIS)

    Oder, Bernhard; Loewe, Maria; Reisegger, Michael; Thurnher, Siegfried A.; Lang, Wilfried; Ilias, Wilfried

    2008-01-01

    Oxygen-ozone nucleolysis (ONL) is a new, minimally invasive procedure for the treatment of discogenic low back pain with or without radicular symptoms. The aim of the present study was to determine associations between the morphology of the basic disease, patient-specific factors and the outcome of the treatment. Six hundred and twelve patients not responding to conservative therapy were divided into five groups (disc bulging, disc herniation, postoperative patients, osteochondrosis, others) and subjected to nucleolysis with ozone and to periradicular infiltration with steroids and local anaesthesia. The success of treatment was assessed by means of a visual analog pain scale (VAS) and the Oswestry Disability Index (ODI). A significant reduction in the VAS was registered after 2 and 6 months (from 8.6 to 5.4 and 6.0; p<0.001) in all patient groups; an excellent therapy response (VAS below 3.0) was achieved by about a third of the patients. A significant improvement in ODI was registered in all patients (46 to 31; p<0.001), most pronounced in the herniation group (25.5, p=0.015). Patients below 50 years had significantly better values in the VAS and ODI score 6 months after treatment. Final VAS and ODI scores for patients with a single diseased segment were 4.2 and 28.0, in two affected segments 6.5 and 32 and in three segments 6.7 and 38.5 (p<0.001 and p=0.051). ONL with periradicular steroid therapy might exert a functional and sustained analgesic effect in patients with degenerative changes in the lumbar spine not responding to conservative therapy and was most effective below 50 years with disc herniation in one segment. (orig.)

  1. Electron beam treatment plant for textile dyeing wastewater

    International Nuclear Information System (INIS)

    Han, B.; Kim, J.; Kim, Y.; Choi, J.; Ahn, S.; Makarov, I.E.; Ponomarev, A.V.

    2006-01-01

    A pilot plant for treating 1,000 m 3 of textile dyeing wastewater per day with electron beam has constructed and operated continuously in Daegu, Korea since 1998. This plant is combined with biological treatment system and it shows the reduction of chemical reagent consumption, and also the reduction in retention time with the increase in removal efficiencies of COD Cr and BOD 5 up to 30∼40%. Increase in biodegradability after radiation treatment of aqueous-organic systems is due to radiolytical conversions of non-biodegradable compounds. On the basis of data obtained from pilot plant operation, construction of actual industrial scale plant has started in 2003, and will be finished by 2005. This plant is located on the area of existing wastewater treatment facility (Daegu Dyeing Industrial Complex) and to have treatment capacity 10,000 m 3 of wastewater per day using one 1 MeV, 400 kW accelerator, and combined with existing bio- treatment facility. The overall construction cost and the operation cost in the radiation processing, when compared to other conventional and advanced oxidation techniques, are more cost-effective and convenient for wastewater treatment. This project is supported by the International Atomic Energy Agency (IAEA) and Korean Government. (author)

  2. Basic research on flue gas smoke treatment by electron beam

    International Nuclear Information System (INIS)

    Namba, Hideki

    1995-01-01

    Recently, accompanying the increase of the use of fossil fuel, the environment destruction due to the sulfur oxides and nitrogen oxides contained in combustion smoke has become a serious problem. The development of flue gas smoke treatment technology by using electron beam was started in Japan, and attention has been paid worldwide as the promising dry type simultaneous desulfurizing and denitrating process. In this process, by adding ammonia to smoke, and irradiating electron beam on it, ammonium nitrate and ammonium sulfate are formed. As to the reaction mechanism of denitration and desulfurization, radical formation, radical reaction, denitration mechanism, desulfurization mechanism, the particle size distribution of the formed aerosol, the amounts of denitration and desulfurization by electron beam smoke treatment process, the improvement of the denitration efficiency by multi-stage irradiation method and the improvement of the desulfurization rate by low temperature irradiation, and the basic test toward the pilot test are explained. The basic research for putting this system to practical use was carried out jointly by Japan Atomic Energy Research Institute, Chubu Electric Power Co., Inc., and Ebara Seisakusho for standard coal burning smoke in Japan. The verifying test at the pilot plant in Shinnagoya Thermal Power Station was carried out, and it was verified that this process can be used practically for treating coal-burning smoke. (K.I.)

  3. Band-Bending of Ga-Polar GaN Interfaced with Al2O3 through Ultraviolet/Ozone Treatment.

    Science.gov (United States)

    Kim, Kwangeun; Ryu, Jae Ha; Kim, Jisoo; Cho, Sang June; Liu, Dong; Park, Jeongpil; Lee, In-Kyu; Moody, Baxter; Zhou, Weidong; Albrecht, John; Ma, Zhenqiang

    2017-05-24

    Understanding the band bending at the interface of GaN/dielectric under different surface treatment conditions is critically important for device design, device performance, and device reliability. The effects of ultraviolet/ozone (UV/O 3 ) treatment of the GaN surface on the energy band bending of atomic-layer-deposition (ALD) Al 2 O 3 coated Ga-polar GaN were studied. The UV/O 3 treatment and post-ALD anneal can be used to effectively vary the band bending, the valence band offset, conduction band offset, and the interface dipole at the Al 2 O 3 /GaN interfaces. The UV/O 3 treatment increases the surface energy of the Ga-polar GaN, improves the uniformity of Al 2 O 3 deposition, and changes the amount of trapped charges in the ALD layer. The positively charged surface states formed by the UV/O 3 treatment-induced surface factors externally screen the effect of polarization charges in the GaN, in effect, determining the eventual energy band bending at the Al 2 O 3 /GaN interfaces. An optimal UV/O 3 treatment condition also exists for realizing the "best" interface conditions. The study of UV/O 3 treatment effect on the band alignments at the dielectric/III-nitride interfaces will be valuable for applications of transistors, light-emitting diodes, and photovoltaics.

  4. CHARACTERIZATION OF OZONE EMISSIONS FROM AIR CLEANERS EQUIPPED WITH OZONE GENERATORS AND SENSOR AND FEEDBACK CONTROL CIRCUITRY

    Science.gov (United States)

    The paper give results of a characterization of ozone emissions from air cleaners equipped with ozone generators and sensor and feedback control circuitry. Ozone emission rates of several consumer appliances, marketed as indoor air treatment or air purification systems, were det...

  5. Construction of Industrial Electron Beam Plant for Wastewater Treatment

    International Nuclear Information System (INIS)

    Han, B.; Kim, J.; Kim, Y.; Kim, S.; Lee, M.; Choi, J.; Ahn, S.; Makarov, I.E.; Ponomarev, A.V.

    2004-01-01

    A pilot plant for treating 1,000 m3/day of dyeing wastewater with e-beam has been constructed and operated since 1998 in Daegu, Korea together with the biological treatment facility. The wastewater from various stages of the existing purification process has been treated with electron beam in this plant, and it gave rise to elaborate the optimal technology of the electron beam treatment of wastewater with increased reliability at instant changes in the composition of wastewater. Installation of the e-beam pilot plant resulted in decolorizing and destructive oxidation of organic impurities in wastewater, appreciable to reduction of chemical reagent consumption, in reduction of the treatment time, and in increase in flow rate limit of existing facilities by 30-40%. Industrial plant for treating 10,000 m3/day, based upon the pilot experimental result, is under construction and will be finished by 2005. This project is supported by the International Atomic Energy Agency (IAEA) and Korean Government

  6. Electron beam processing programme: Wastewater and sludge treatment in Brazil

    International Nuclear Information System (INIS)

    Sampa, M.H.O.; Rela, P.R.; Duarte, C.L.; Borrely, S.I.; Vieira, J.M.

    1998-01-01

    The Institute for Energetic and Nuclear Research, working on environmental applications, has an extensive research programme using high energy electron beam in treating industrial wastewater and sludge. The experiments are being conducted in a pilot plant using an industrial electron beam 1.5MeV, 25mA, where the streams are presented to the scanned electron beam in counter flow. This pilot plant is designed to process approximately 3.0m 3 /h with an average dose 5kGy and the absorbed dose measurement is performed continuously by calorimetric system in real time. Combined biological and radiation treatment of domestic sewage and sludge were carried out to investigate disinfestation and removal of organic matter. The experiments showed that total and fecal coliforms were decreased by about 5 logs cycles with a 3.0kGy radiation dose in raw sewage and biological effluents, respectively. Concerning the industrial wastewater in the first stage of the programme, the irradiation was conducted using batch systems with samples originating from a Governmental Wastewater Treatment Plant. The data showed a significant color reduction effect when delivered dose was increased, and the opposite was noted for turbidity and total suspended solids. Other experiments were focused to process real industrial effluents from one of the most important chemical and pharmaceutical industries in Brazil. A special transport truck was used to transfer the liquid waste from the Industry to the Electron Beam Pilot Plant. Large quantities of liquid waste were irradiated with and without air addition with the doses from 2kGy to 20kGy. Such experiences performed in association with the Industry demonstrated that this technology has a great potential to be transferred and to contribute with a permanent cleanup alternative for hazardous wastes

  7. Ozonation and sol-gel method to obtain Cu/Cu O nanoparticles from cyanidation wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Soria A, M. J.; Puente S, D. M.; Carrillo P, F. R. [Universidad Autonoma de Coahuila, Facultad de Metalurgia, Carretera 57 Km 4.5, 25710 Monclova, Coahuila (Mexico); Garcia C, L. A. [Centro de Investigacion en Quimica Aplicada, Blvd. Enrique Reyna No. 140, Col. Los Pinos, 25253 Saltillo, Coahuila (Mexico); Velazquez S, J., E-mail: frrcarrillo@yahoo.com.mx [University of Texas at San Antonio, Department of Physics and Astronomy, San Antonio TX 78249 (United States)

    2015-07-01

    The extraction process of gold and silver by cyanidation generates large amounts of effluent which also contain contaminants such as cyanide and significant metal values such as copper. This paper presents the results of the removal and recovery of copper from ozonation treatment of a residual aqueous cyanide. The residual solution was treated by ozonation-precipitation to obtain a precipitate of copper. From this, copper nano composites obtained by Pechini modified sol-gel method were obtained. The compounds obtained were characterized by X-ray diffraction, showing a dependence of the type of compounds formed over time of ozonation and heat treatment of the gel. The particle size was measured by scanning electron microscopy and calculated by the Scherrer equation, being between 50 and 120 nm. (Author)

  8. An experimental investigation of wastewater treatment using electron beam irradiation

    Science.gov (United States)

    Emami-Meibodi, M.; Parsaeian, M. R.; Amraei, R.; Banaei, M.; Anvari, F.; Tahami, S. M. R.; Vakhshoor, B.; Mehdizadeh, A.; Fallah Nejad, N.; Shirmardi, S. P.; Mostafavi, S. J.; Mousavi, S. M. J.

    2016-08-01

    Electron beam (EB) is used for disinfection and treatment of different types of sewage and industrial wastewater. However, high capital investment required and the abundant energy consumed by this process raise doubts about its cost-effectiveness. In this paper, different wastewaters, including two textile sewages and one municipal wastewater are experimentally studied under different irradiation strategies (i.e. batch, 60 l/min and 1000 m3/day) in order to establish the reliability and the optimum conditions for the treatment process. According to the results, EB improves the efficiency of traditional wastewater treatment methods, but, for textile samples, coagulation before EB irradiation is recommended. The cost estimation of EB treatment compared to conventional methods shows that EB has been more expensive than chlorination and less expensive than activated sludge. Therefore, EB irradiation is advisable if and only if conventional methods of textile wastewater treatment are insufficient or chlorination of municipal wastewater is not allowed for health reasons. Nevertheless, among the advanced oxidation processes (AOP), EB irradiation process may be the most suitable one in industrial scale operations.

  9. Two-phase ozonation of chlorinated organics

    International Nuclear Information System (INIS)

    Bhattacharyya, D.; Freshour, A.; West, D.

    1995-01-01

    In the last few years the amount of research being conducted in the field of single-phase ozonation has grown extensively. However, traditional aqueous-phase ozonation systems are limited by a lack of selective oxidation potential, low ozone solubility in water, and slow intermediate decomposition rates. Furthermore, ozone may decompose before it can be utilized for pollutant destruction since ozone can be highly unstable in aqueous solutions. Naturally occurring compounds such as NaHCO 3 also affect ozone reactions by inhibiting the formation of OH-free radicals. To compensate for these factors, excess ozone is typically supplied to a reactor. Since ozone generation requires considerable electric power consumption (16 - 24 kWh/kg of O 3 ), attempts to enhance the ozone utilization rate and stability should lead to more efficient application of this process to hazardous waste treatment. To improve the process, ozonation may be more efficiently carried out in a two-phase system consisting of an inert solvent (saturated with O 3 ) contacted with an aqueous phase containing pollutants. The non-aqueous phase must meet the following criteria: (1) non-toxic, (2) very low vapor pressure, (3) high density (for ease of separation), (4) complete insolubility in water, (5) reusability, (6) selective pollutant extractability, (7) high oxidant solubility, and (8) extended O 3 stability. Previously published studies (1) have indicated that a number of fluorinated hydrocarbon compounds fit these criteria. For this project, FC40 (a product of 3M Co.) was chosen due to its low vapor pressure (3 mm Hg) and high specific gravity (1.9). The primary advantages of the FC40 solvent are that it is non-toxic, reusable, has an ozone solubility 10 times that of water, and that 85 % of the ozone remains in the solvent even after 2 hours. This novel two-phase process has been utilized to study the rapid destruction of organic chlorine compounds and organic mixtures

  10. Dosimetry for combustion flue gas treatment with electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Mehta, K.; Bułka, S.; Sun, Y. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

    2011-07-01

    The electron beam treatment of flue gas is one of the new technologies. There are several reasons for carrying out dosimetry at various phases of the project as understanding the process and optimizing the equipment, for process control and for troubleshooting in case of malfunction etc. The main challenge in measuring dose for flue gas applications is that the medium being irradiated is gaseous. Two general approaches for dose measurements are: adding/placing some dosimeters in the reaction vessel (gas) and using the components of the gas itself as a dosimeter. Various techniques and methods have been tried which are discussed in this paper. (author)

  11. Secondary maxima in ozone profiles

    Directory of Open Access Journals (Sweden)

    R. Lemoine

    2004-01-01

    Full Text Available Ozone profiles from balloon soundings as well as SAGEII ozone profiles were used to detect anomalous large ozone concentrations of ozone in the lower stratosphere. These secondary ozone maxima are found to be the result of differential advection of ozone-poor and ozone-rich air associated with Rossby wave breaking events. The frequency and intensity of secondary ozone maxima and their geographical distribution is presented. The occurrence and amplitude of ozone secondary maxima is connected to ozone variability and trend at Uccle and account for a large part of the total ozone and lower stratospheric ozone variability.

  12. Treatment of textiles industrial wastewater by electron beam and biological treatment (sbr)

    International Nuclear Information System (INIS)

    Khomsaton Abu Bakar; Khairul Zaman Mohd Dahlan; Zulkafli Ghazali; Ting Teo Ming

    2008-08-01

    Study of treating textiles industrial wastewater with combined of electron beam and Tower Style Biological Treatment (TSB) was investigated in Korea. In this project, textiles wastewater was also treated with electron beam, but hybrid with Sequencing Batch Reactor (SBR). The purpose of this research is to develop combined electron beam treatment with existing biological treatment facility (SBR), of textile industries in Malaysia. The objectives of this project are to determine the effective irradiation parameter for treatment and to identify effective total retention time in SBR system. To achieve the objective, samples fill in polypropyle tray were irradiated at 1 MeV, 20 mA and 1 MeV ,5 mA at doses 11, 20, 30, 40 and 50 kGy respectively. Raw effluent and two series of irradiated effluent at 1 MeV 20 mA (11, 20, 30, 40 and 50 kGy) and 1 MeV 5 mA (11, 20, 30, 40 and 50 kGy) were then treated in SBR system. Samples were analysed at 6, 14 and 20 hrs after aeration in the SBR. The results show that, average reduction in BOD was about 2-11% after irradiated at 5 mA, and the percentage increased to 21-73% after treatment in SBR system. At 20 mA, BOD reduced to 7-29% during irradiation and the value increased to 57-87% after treatment in SBR system. (Author)

  13. Cr(VI) formation during ozonation of Cr-containing materials in ...

    African Journals Online (AJOL)

    Ozonation, or advanced oxidation processes (utilising ozone decomposition products as oxidants) are widely used in industrial wastewater and drinking water treatment plants. In these applications the use of ozone is based on ozone and its decomposition by-products being strong oxidants. In this paper, the possible ...

  14. Impacto del tratamiento con ozono sobre las propiedades superficiales del carbón activado Impact of ozone treatment on activated carbon surface properties

    Directory of Open Access Journals (Sweden)

    Héctor Valdés

    2011-08-01

    Full Text Available El uso conjunto de ozono y carbón activado para tratar efluentes tóxicos ha sido demostrado recientemente. Sin embargo, existen dudas acerca del efecto del ozono sobre las propiedades del carbón activado. En este artículo se presentan resultados sobre la modificación de las propiedades superficiales de un carbón activado comercial por la acción del ozono durante diferentes tiempos de exposición. Las propiedades químicas superficiales del carbón activado fueron evaluadas utilizando las técnicas de neutralización selectiva, desorción térmica programada (DTP y el pH del punto de carga cero. Las características texturales fueron evaluadas mediante microscopía electrónica de barrido. El área superficial aparente, el volumen de microporos y mesoporos fueron obtenidos a partir de las isotermas de adsorción de nitrógeno a 77 K. Las propiedades adsortivas fueron caracterizadas por el índice de adsorción de azul de metileno. Los resultados demuestran que los grupos superficiales oxigenados presentes en el carbón activado se modifican producto del tratamiento con el ozono. A mayores dosis de ozono, el carbón sufre mayor oxidación y se incrementan los grupos ácidos en especial los grupos carboxílicos, mientras que el pH de punto de carga cero disminuye. El área BET, así como el volumen de microporos disminuyen al igual que el poder de adsorción de azul de metileno.The combined use of ozone and activated carbon has recently started to be developed for the treatment of toxic effluents. However, the effect of ozone on the properties of activated carbon is not fully elucidated. A study was undertaken of modifications of the surface properties of a commercial activated carbon produced by its ozonation during different time periods. Surface chemistry of the activated carbon samples was characterized by of selective neutralization, temperature-programmed desorption, and pH of the point of zero charge. Surface area and volume of

  15. Development of an irradiation device for electron beam wastewater treatment

    International Nuclear Information System (INIS)

    Rela, Paulo Roberto

    2003-01-01

    When domestic or industrial effluents with synthetic compounds are disposed without an adequate treatment, they impact negatively the environment with damages to aquatic life and for the human being. Both population and use of goods and services that contribute for the hazardous waste are growing. Hazardous regulations are becoming more restrictive and technologies, which do not destroy these products, are becoming less acceptable. The electron beam radiation process is an advanced oxidation process, that produces highly reactive radicals resulting in mineralization of the contaminant. In this work was developed an irradiation system in order to optimize the interaction of electron beam delivered from the accelerator with the processed effluent. It is composed by an irradiation device where the effluent presents to the electron beam in an up flow stream and a process control unit that uses the calorimetric principle. The developed irradiation device has a different configuration from the devices used by others researchers that are working with this technology. It was studied the technical and economic feasibility, comparing with the literature the results of the irradiation device demonstrated that it has a superior performance, becoming an process for use in disinfection and degradation of hazardous organic compounds of wastewater from domestic and industrial origin, contributing as an alternative technology for Sanitary Engineering. (author)

  16. Electron beam coal combustion flue gas treatment developments in Poland

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    1994-01-01

    The research on EB(electron beam) flue gas treatment has started in Poland since 1985. It followed early tests performed in Japan, USA and Germany. The first tests using batch method were carried out in Institute of Atomic Energy. The continuous flow laboratory installation (400 Nm 3 /h) has been constructed in the Institute of Nuclear Chemistry and Technology (INCT) then. This installation containing ILV-6 electron beam accelerator (power 20 kW, energy of electrons 0-2 MeV) is equipped with additional microwaves generator. The eb or eb/mw energy can be applied to treated flue gas. On the basis of laboratory test an industrial pilot plant has been constructed at EPS Kaweczyn near Warsaw. At this plant being the biggest of this kind (20 000 Nm 3 /h) for the first time in industrial conditions multistage irradiation has been applied (two ELW-3 accelerators 50 kW each, energy of electrons 600-800 keV). High efficiency of SO 2 and NO x simultaneous removal, usable product (fertilizer), lower (in comparison with conventional technologies - FGD/SCR) investment and operational costs are the main advantages which have led to decision about starting demonstration industrial project. Feasibility study has been prepared for EPS Pomorzany, Szczecin, Poland. The plant planned will treat flue gases from power/heat generation block (2 Benson type boilers 56 MW e plus 40 MW th each). To meet Polish limits of 1997 half of flue gases will be treated with removal efficiency of 90% for SO 2 and 70% for NO x . Total flow rate will be equal to 270 000 Nm 3 /h. (author)

  17. Optimized lens-sparing treatment of retinoblastoma with electron beams

    International Nuclear Information System (INIS)

    Steenbakkers, Roel J.H.M.; Altschuler, Martin D.; D'Angio, Giulio J.; Goldwein, Joel W.; Kassaee, Alireza

    1997-01-01

    Purpose: The ideal lens-sparing radiotherapy technique for retinoblastoma calls for 100% dose to the entire retina including the ora serrata and zero dose to the lens. Published techniques, most of which use photons, have not accomplished this ideal treatment. We describe here a technique that approaches this ideal configuration using electron beam therapy. Methods and Materials: Dose-modeling calculations were made using a computer program built around a proprietary algorithm. This program calculates 3D dose distribution for electrons and photons and uses the Cimmino feasibility method for the inverse problem of beam weighting to achieve the prescribed dose. The algorithm has been verified in the ocular region by measurements in a RANDO phantom. To search for an ideal lens-sparing beam setup, a stylized phantom of an 8-month-old infant was generated with built-in inhomogeneities, and a phantom of a 5-year-old child was generated from a patient CT series. Results: Of more than 100 different beam setups tested, two 9 MeV electron beams at gantry angles plus and minus 26 degrees from the optic nerve axis achieved the best distribution. Both fields have a lens block and an isocenter between the globe and origin of the optic nerve. When equal doses are given to both fields, the entire extent of the retina (including ora serrata) received 100%, while the lens received 10% or less. Conclusion: The two-oblique-electron-beam technique here described appears to meet most of the stringent dosimetry needed to treat retinoblastoma. It is suitable for a range of ages, from infancy to early childhood years

  18. Finding the lost open-circuit voltage in polymer solar cells by UV-ozone treatment of the nickel acetate anode buffer layer.

    Science.gov (United States)

    Wang, Fuzhi; Sun, Gang; Li, Cong; Liu, Jiyan; Hu, Siqian; Zheng, Hua; Tan, Zhan'ao; Li, Yongfang

    2014-06-25

    Efficient polymer solar cells (PSCs) with enhanced open-circuit voltage (Voc) are fabricated by introducing solution-processed and UV-ozone (UVO)-treated nickel acetate (O-NiAc) as an anode buffer layer. According to X-ray photoelectron spectroscopy data, NiAc partially decomposed to NiOOH during the UVO treatment. NiOOH is a dipole species, which leads to an increase in the work function (as confirmed by ultraviolet photoemission spectroscopy), thus benefitting the formation of ohmic contact between the anode and photoactive layer and leading to increased Voc. In addition, the UVO treatment improves the wettability between the substrate and solvent of the active layer, which facilitates the formation of an upper photoactive layer with better morphology. Further, the O-NiAc layer can decrease the series resistance (Rs) and increase the parallel resistance (Rp) of the devices, inducing enhanced Voc in comparison with the as-prepared NiAc-buffered control devices without UVO treatment. For PSCs based on the P3HT:PCBM system, Voc increases from 0.50 to 0.60 V after the NiAc buffer layer undergoes UVO treatment. Similarly, in the P3HT:ICBA system, the Voc value of the device with a UVO-treated NiAc buffer layer increases from 0.78 to 0.88 V, showing an enhanced power conversion efficiency of 6.64%.

  19. Enzymatic changes in intact leaves of Phaseolus vulgaris following ozone fumigation

    Energy Technology Data Exchange (ETDEWEB)

    Dass, H C; Weaver, G M

    1972-01-01

    Enzymatic changes in the intact leaves of Phaseolus vulgaris cv. Seaway 65 were studied following ozone fumigation. It was found that peroxidase enzyme increased significantly with the ozone treatment in the first 48 h. Similarly, cellulase enzyme showed significant increase 48 h. following ozone treatment. Lactic dehydrogenase activity was not markedly affected by ozone treatment. Disc electrophoretic studies of peroxidase isoenzymes showed that ozone treatment induced a new band of peroxidase. The role of peroxidase, cellulase and lactic dehydrogenase enzymes is discussed in relation to ozone damage and the bronzing disorder in white beans. 22 references, 1 figure, 1 table.

  20. The Antarctic ozone hole

    International Nuclear Information System (INIS)

    Jones, Anna E

    2008-01-01

    Since the mid 1970s, the ozone layer over Antarctica has experienced massive destruction during every spring. In this article, we will consider the atmosphere, and what ozone and the ozone layer actually are. We explore the chemistry responsible for the ozone destruction, and learn about why conditions favour ozone destruction over Antarctica. For the historical perspective, the events leading up to the discovery of the 'hole' are presented, as well as the response from the international community and the measures taken to protect the ozone layer now and into the future

  1. Lightweight ozonizer for field and airborne use

    Science.gov (United States)

    Stone, E. J.; Caldwell, J. R.; de Waal, C.; Horvath, J. J.; Pearson, R., Jr.; Stedman, D. H.

    1982-12-01

    An efficient, lightweight apparatus for the production of ozone in flowing oxygen or air has been constructed and tested. The exciter is an automotive electronic ignition running from a 28-V dc power source. The discharge tube consists of coaxial conductive-coated flint glass tubing fitting into Teflon end pieces. A single such unit will produce 4% ozone in oxygen flowing at 0.2 l/min, or a maximum of 0.020 l of ozone per minute in a total flow of 1.0 l/min.

  2. Ozone pretreatment and fermentative hydrolysis of wheat straw

    Science.gov (United States)

    Ben'ko, E. M.; Chukhchin, D. G.; Lunin, V. V.

    2017-11-01

    Principles of the ozone pretreatment of wheat straw for subsequent fermentation into sugars are investigated. The optimum moisture contents of straw in the ozonation process are obtained from data on the kinetics of ozone absorbed by samples with different contents of water. The dependence of the yield of reducing sugars in the fermentative reaction on the quantity of absorbed ozone is established. The maximum conversion of polysaccharides is obtained at ozone doses of around 3 mmol/g of biomass, and it exceeds the value for nonozonated samples by an order of magnitude. The yield of sugar falls upon increasing the dose of ozone. The process of removing lignin from the cell walls of straw during ozonation is visualized by means of scanning electron microscopy.

  3. Physicochemical characteristics of ozonated sunflower oils obtained by different procedures

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, M. F.; Sanchez, Y.; Gomez, M.; Hernandez, F.; Veloso, M. C.; Pereira, P. A.; Mangrich, A. S.; Andrade, J. B.

    2012-07-01

    Two ozonation procedures for sunflower oils at different applied ozone dosages were carried out. Ozone was obtained from medicinal oxygen and from air. Peroxide, acidity, and iodine indexes, along with density, viscosity and antimicrobial activity were determined. The fatty acid compositions of the samples were analyzed using GC. The content of oxygen was determined using an elemental analysis. Electronic Paramagnetic Resonance was used to measure the organic free radicals. The reactions were achieved up to peroxide index values of 658 and 675 mmolequiv kg1 using medicinal oxygen and air for 5 and 8 hours, respectively. The samples of ozonized sunflower oil did not present organic free radicals, which is a very important issue if these oils are to be used as drugs. The ozonation reaction is more rapid with medicinal oxygen (5 hours) than with air (8 hours). Ozonized sunflower oil with oxygen as an ozone source was obtained with high potential for antimicrobial activity. (Author) 34 refs.

  4. Industrial plant for electron beam flue gas treatment

    International Nuclear Information System (INIS)

    Chmielewski, A.G.; Iller, E.; Tyminnski, B.; Zimek, Z; Ostapczuk, A.; Licki, J.

    2001-01-01

    The electron beam flue gas treatment technology was invented many years ago. Research on the process has been carried out in Japan, USA, Germany and Poland. However, the recent fidings, based on the experiments performed at pilot plant at Electric Power Station Kaweczyn, led to developments which made process mature just at the dawn of the XXI century. The process is being implemented in the full industrial scale at Electric Power Station Pomorzany (Dolna Odra EPS Group). Other developments are reported in Japan and after Nagoya's pilot plant experiments, an industrial plant has been built in China and another one is constructed in Japan. There are remarkable differences in technological and design solutions applied in all these installations. Developments achieved at EPS Kaweczyn pilot plant and INCT laboratory unit were the basis for the project realized at EPS Pomorzan

  5. Electron beam treatment planning: A review of dose computation methods

    International Nuclear Information System (INIS)

    Mohan, R.; Riley, R.; Laughlin, J.S.

    1983-01-01

    Various methods of dose computations are reviewed. The equivalent path length methods used to account for body curvature and internal structure are not adequate because they ignore the lateral diffusion of electrons. The Monte Carlo method for the broad field three-dimensional situation in treatment planning is impractical because of the enormous computer time required. The pencil beam technique may represent a suitable compromise. The behavior of a pencil beam may be described by the multiple scattering theory or, alternatively, generated using the Monte Carlo method. Although nearly two orders of magnitude slower than the equivalent path length technique, the pencil beam method improves accuracy sufficiently to justify its use. It applies very well when accounting for the effect of surface irregularities; the formulation for handling inhomogeneous internal structure is yet to be developed

  6. Electron beam treatment of simulated marine diesel exhaust gases

    Directory of Open Access Journals (Sweden)

    Licki Janusz

    2015-09-01

    Full Text Available The exhaust gases from marine diesel engines contain high SO2 and NOx concentration. The applicability of the electron beam flue gas treatment technology for purification of marine diesel exhaust gases containing high SO2 and NOx concentration gases was the main goal of this paper. The study was performed in the laboratory plant with NOx concentration up to 1700 ppmv and SO2 concentration up to 1000 ppmv. Such high NOx and SO2 concentrations were observed in the exhaust gases from marine high-power diesel engines fuelled with different heavy fuel oils. In the first part of study the simulated exhaust gases were irradiated by the electron beam from accelerator. The simultaneous removal of SO2 and NOx were obtained and their removal efficiencies strongly depend on irradiation dose and inlet NOx concentration. For NOx concentrations above 800 ppmv low removal efficiencies were obtained even if applied high doses. In the second part of study the irradiated gases were directed to the seawater scrubber for further purification. The scrubbing process enhances removal efficiencies of both pollutants. The SO2 removal efficiencies above 98.5% were obtained with irradiation dose greater than 5.3 kGy. For inlet NOx concentrations of 1700 ppmv the NOx removal efficiency about 51% was obtained with dose greater than 8.8 kGy. Methods for further increase of NOx removal efficiency are presented in the paper.

  7. Application of a dummy eye shield for electron treatment planning

    International Nuclear Information System (INIS)

    Kang, Sei-Kwon; Park, Soah; Hwang, Taejin; Cheong, Kwang-Ho; Han, Taejin; Kim, Haeyoung; Lee, Me-Yeon; Kim, Kyoung Ju; Oh, Do Hoon; Bae, Hoonsik

    2013-01-01

    Metallic eye shields have been widely used for near-eye treatments to protect critical regions, but have never been incorporated into treatment plans because of the unwanted appearance of the metal artifacts on CT images. The purpose of this work was to test the use of an acrylic dummy eye shield as a substitute for a metallic eye shield during CT scans. An acrylic dummy shield of the same size as the tungsten eye shield was machined and CT scanned. The BEAMnrc and the DOSXYZnrc were used for the Monte Carlo (MC) simulation, with the appropriate material information and density for the aluminum cover, steel knob and tungsten body of the eye shield. The Pinnacle adopting the Hogstrom electron pencil-beam algorithm was used for the one-port 6-MeV beam plan after delineation and density override of the metallic parts. The results were confirmed with the metal oxide semiconductor field effect transistor (MOSFET) detectors and the Gafchromic EBT2 film measurements. For both the maximum eyelid dose over the shield and the maximum dose under the shield, the MC results agreed with the EBT2 measurements within 1.7%. For the Pinnacle plan, the maximum dose under the shield agreed with the MC within 0.3%; however, the eyelid dose differed by -19.3%. The adoption of the acrylic dummy eye shield was successful for the treatment plan. However, the Pinnacle pencil-beam algorithm was not sufficient to predict the eyelid dose on the tungsten shield, and more accurate algorithms like MC should be considered for a treatment plan. (author)

  8. Pyrolytic citrate synthesis and ozone annealing

    International Nuclear Information System (INIS)

    Celani, F.; Saggese, A.; Giovannella, C.; Messi, R.; Merlo, V.

    1988-01-01

    A pyrolytic procedure is described that via a citrate synthesis allowed us to obtain very fine grained YBCO powders that, after a first furnace thermal treatment in ozone, results already to contain a large amount of superconducting microcrystals. A second identical thermal treatment gives a final product strongly textured, as shown by magnetic torque measurements. Complementary structural and diamagnetic measurement show the high quality of these sintered pellets. The role covered by both the pyrolytic preparation and the ozone annealing are discussed

  9. Anti-Inflammatory and Tissue Regenerative Effects of Topical Treatment with Ozonated Olive Oil/Vitamin E Acetate in Balanitis Xerotica Obliterans

    Directory of Open Access Journals (Sweden)

    Monica Currò

    2018-03-01

    Full Text Available Balanitis xerotica obliterans (BXO is a chronic inflammatory skin disorder, considered the male genital variant of lichen sclerosus. Anti-inflammatory drugs are commonly used in BXO. We evaluated the effects of an innovative formulation of ozonated olive oil with vitamin E acetate (OZOILE® on the inflammatory status and tissue remodeling in male children with BXO. The mRNA transcripts of proteins involved either in inflammation or in dynamics of tissue regeneration were analyzed by quantitative real-time PCR, in foreskins affected by BXO removed from patients untreated or treated with OZOILE® cream for 7 days before circumcision. We found a significant reduction in mRNA levels of IL-1β, TNF-α, INF–γ, transglutaminase 2 and NOS2 in foreskins treated with OZOILE® in comparison to untreated ones (p < 0.001. No significant differences were observed in NF-κB activation in the specimens obtained from treated and untreated patients. Hence, OZOILE® treatment up-regulated hypoxia-inducible factor (HIF-1alpha, vascular endothelial growth factor (VEGF and E-cadherin gene expression (p < 0.001. The treatment with OZOILE® showed effective results in children affected by BXO by reducing the inflammatory process and stimulating mechanisms for tissue regeneration of the foreskin. A randomized clinical trial on a large number of children affected by BXO might be useful to verify the efficacy of topical treatment with OZOILE®.

  10. Effect of Pulse Width on Ozone Generation in Pulsed Streamer Discharges

    OpenAIRE

    Tamaribuchi, Hiroyuki; Wang, Douyan; Namihira, Takao; Katsuki, Sunao; Akiyama, Hidenori; タマリブチ, ヒロユキ; オウ, トエン; ナミヒラ, タカオ; カツキ, スナオ; アキヤマ, ヒデノリ; 溜渕, 浩之; 王, 斗艶; 浪平, 隆男; 勝木, 淳; 秋山, 秀典

    2007-01-01

    Ozone has been used in treatment of drinking water andwaste water (e.g., deodorization, decolorization, anddisinfection). Though general ozonizers based on silentdischarge or barrier discharge have been used to supplyozone at many industrial situations, there is still someproblem, such as improvements of ozone concentrationand ozone yield.In this work, ozone was generated by pulsed powerdischarge in order to improve the characteristics of ozonegeneration. High electric field with short pulse ...

  11. Demonstration plant of smoke treatment by electron beam irradiation

    International Nuclear Information System (INIS)

    Kawamura, Keita

    1989-01-01

    The acid rain caused by sulfur oxides and nitrogen oxides has become the large social problem as it damages forests, lakes and agricultural crops and also buildings in Europe and America. In such circumstances, concern has been expressed in various countries on the smoke treatment technology, EBA process, which removes the sulfur oxides and nitrogen oxides contained in smoke simultaneously by irradiating electron beam on the smoke which is exhausted from power station boilers and industrial boilers and mainly causes acid rain. The research and development of this technology were begun in 1971 based on the original idea of Ebara Corp., and from 1972, those were advanced as the joint research with Japan Atomic Energy Research Institute. Thereafter, by the joint research with the technical research association on prevention of nitrogen oxides in iron and steel industry, by ammonia addition and irradiation process, the desulfurization and denitration performance was heightened, and the byproduct was successfully captured as powder, in this way, the continuous dry treatment process was established. The demonstration test plant was constructed in a coal-firing power station in Indiana, USA, and the trial operation was carried out from 1985 for two years. (K.I.)

  12. Shelf life characteristics of bread produced from ozonated wheat flour.

    Science.gov (United States)

    Obadi, Mohammed; Zhu, Ke-Xue; Peng, Wei; Sulieman, Abdellatif A; Mahdi, Amer Ali; Mohammed, Khalid; Zhou, Hui-Ming

    2017-11-13

    The objective of this work was to study the effect of ozone treatment on the quality of bread and its shelf life. Flour was treated with ozone gas a rate of 5 L/min for 5, 15, 25, 35, and 45 min. Baking studies showed that bread made from flour treated with ozone for 15 min exhibited improved quality properties (in terms of specific volume, bread color, and crumb cell numbers). Exposure to ozone for shorter times did not cause obvious changes in the major volatile compounds of bread. A shelf life tests showed that ozone gas treatment influenced the extent of starch crystallinity. The relative starch crystallinity of bread made from flour treated with ozone for 15 min was lower than the control value, as were the hardness, springiness, and cohesiveness. Microscopic examination of crumb structure revealed remarkable differences between control and treated breads. Although ozone is a naturally occurring substance found in the atmosphere, ozone can also be produced synthetically. Recently, ozone has come to be regarded as a new treatment for flour. Especially in countries where the chlorination is forbidden, ozone treatment may be of a great interest if it were associated with significant and reliable changes in flour. Ozone treatment of wheat flour tends to improve bread shelf life and quality in terms of physiochemical, baking properties, X-ray diffraction data, volatile compound levels, crumb structure, and textural characteristics. Given such findings, desirable shelf life and bread qualities may be achieved when ozone is used as a flour oxidant prior to bread baking. Analyses of the effects of ozone gas on treatment of flour on bread shelf life and quality would aid the production of high quality and extend the shelf life of bread. © 2017 Wiley Periodicals, Inc.

  13. Ozone Antimicrobial Efficacy

    Science.gov (United States)

    Ozone is a potent germicide that has been used extensively for water purification. In Europe, 90 percent of the municipal water systems are treated with ozone, and in France, ozone has been used to treat drinking water since 1903. However, there is limited information on the bioc...

  14. Production of ozone using nanosecond short pulsed power

    OpenAIRE

    Shimomura, N.; Wakimoto, M.; Togo, H.; Namihira, Takao; Akiyama, Hidenori; ナミヒラ, タカオ; アキヤマ, ヒデノリ; 浪平, 隆男; 秋山, 秀典

    2003-01-01

    Production of ozone is one of the most typical industrial and commercial applications of electrical discharge. The demand of ozone will be increasing for wholesome and environment-friendly sterilizations. The production of ozone using the pulsed power discharge will apply electron accelerations around the head of streamer discharge. The breakdowns in reactor, however, often limit the efficient production. The pulse shape should be controlled for dimension of the reactor. On the other hand, th...

  15. Formation of Ozonic Compound and Used as Therapeutic Agent in Medicine

    Science.gov (United States)

    Zhu, Lei; Ye, Chunyong; Min, Xinmin

    2018-03-01

    It has some encouraging results to use ozone in medicine. However, as ozone is usually in gas state, unstable and strong oxidability, it is difficult to be stored and used commonly. Ozone, ethylene, acrylic acid and the ozonic compounds were calculated to study the interaction between ozone and carrier material to form ozonide. The stability of the ozonide, or the bond strength between ozone and ions of carrier are controlled felicitously to release ozone from the ozonide with proper velocity. Ozone antimicrobial has been composed on the above principle. It can be used conveniently, especially for common families. There are some characteristics of ozone antimicrobial or ozone, such as universal applicability, efficiency and rapidity, security, strong penetrability, no drug resistance and sterilization and treatment simultaneity.

  16. Earth's ozone layer

    International Nuclear Information System (INIS)

    Lasa, J.

    1991-01-01

    The paper contain the actual results of investigations of the influence of the human activity on the Earth's ozone layer. History of the ozone measurements and of the changes in its concentrations within the last few years are given. The influence of the trace gases on both local and global ozone concentrations are discussed. The probable changes of the ozone concentrations are presented on the basis of the modelling investigations. The effect of a decrease in global ozone concentration on human health and on biosphere are also presented. (author). 33 refs, 36 figs, 5 tabs

  17. Treatment of effluents from ammonia plants--3. Ozonation of amines in an effluent from a reforming plant serving an ammonia complex

    Energy Technology Data Exchange (ETDEWEB)

    Wilde, F G.N.D.

    1977-01-01

    The use of ozone in aqueous solutions was studied in an investigation of the oxidation of methylamines in the process condensate from an ammonia plant. Good conversion of trimethylamine to the nonodorous oxidation product could be achieved with a 1:1.5 ratio of amine to ozone when ozone passed into a packed tower through which an alkaline solution of the amine was flowing. Mono- and dimethylamine did not react as readily. The importance of a high pH value is stressed.

  18. Tropospheric Ozone and Photochemical Smog

    Science.gov (United States)

    Sillman, S.

    2003-12-01

    global background ozone can make the effects of local pollution events everywhere more acute, and can also cause ecological damage in remote locations that are otherwise unaffected by urban pollution. Ozone at the global scale is also related to greenhouse warming.This chapter provides an overview of photochemical smog at the urban and regional scale, focused primarily on ozone and including a summary of information about particulates. It includes the following topics: dynamics and extent of pollution events; health and ecological impacts; relation between ozone and precursor emissions, including hydrocarbons and nitrogen oxides (NOx); sources, composition, and fundamental properties of particulates; chemistry of ozone and related species; methods of interpretation based on ambient measurements; and the connection between air pollution events and the chemistry of the global troposphere. Because there are many similarities between the photochemistry of ozone during pollution events and the chemistry of the troposphere in general, this chapter will include some information about global tropospheric chemistry and the links between urban-scale and global-scale events. Additional treatment of the global troposphere is found in Volume 4 of this work. The chemistry of ozone formation discussed here is also related to topics discussed in greater detail elsewhere in this volume (see Chapters 9.10 and 9.12) and in Volume 4.

  19. The role of dissociation channels of excited electronic states in quantum optimal control of ozone isomerization: A three-state dynamical model

    Energy Technology Data Exchange (ETDEWEB)

    Kurosaki, Yuzuru, E-mail: kurosaki.yuzuru@jaea.go.jp [Quantum Beam Science Directorate, Tokai Research and Development Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Ho, Tak-San, E-mail: tsho@Princeton.EDU [Department of Chemistry, Princeton University, Princeton, NJ 08544 (United States); Rabitz, Herschel, E-mail: hrabitz@Princeton.EDU [Department of Chemistry, Princeton University, Princeton, NJ 08544 (United States)

    2016-05-01

    The prospect of performing the open → cyclic ozone isomerization has attracted much research attention. Here we explore this consideration theoretically by performing quantum optimal control calculations to demonstrate the important role that excited-state dissociation channels could play in the isomerization transformation. In the calculations we use a three-state, one-dimensional dynamical model constructed from the lowest five {sup 1}A′ potential energy curves obtained with high-level ab initio calculations. Besides the laser field-dipole couplings between all three states, this model also includes the diabatic coupling between the two excited states at an avoided crossing leading to competing dissociation channels that can further hinder the isomerization process. The present three-state optimal control simulations examine two possible control pathways previously considered in a two-state model, and reveal that only one of the pathways is viable, achieving a robust ∼95% yield to the cyclic target in the three-state model. This work represents a step towards an ultimate model for the open → cyclic ozone transformation capable of giving adequate guidance about the necessary experimental control field resources as well as an estimate of the ro-vibronic spectral character of cyclic ozone as a basis for an appropriate probe of its formation.

  20. Reactivity and selectivity of arenes in reactions with ozone

    International Nuclear Information System (INIS)

    Vysotskii, Yu.B.; Mestechkin, M.M.; Sivyakova, L.N.; Tyupalo, N.F.

    1987-01-01

    The reactions of arenes with ozone, distinguished by the variety of products (quinones, aldehydes, acids), are of interest not only from the theoretical standpoint but also are of preparative value in the case of polycyclic hydrocarbons. In this work a quantitative treatment of this reaction is given on the basis of direct kinetic measurements and simple quantum chemical means, permitting its rate constants and the yield of the products to be related to the elements of electronic structure readily subject to quantum mechanical calculation

  1. Cooling tower water conditioning study. [using ozone

    Science.gov (United States)

    Humphrey, M. F.; French, K. R.

    1979-01-01

    Successful elimination of cooling tower treatment chemicals was demonstrated. Three towers functioned for long periods of time with ozone as the only treatment for the water. The water in the systems was reused as much as 30 times (cycles of concentration) without deleterious effects to the heat exchangers. Actual system blow-down was eliminated and the only makeup water added was that required to replace the evaporation and mist entrainment losses. Minimum water savings alone are approximately 75.1 1/kg/year. Cost estimates indicate that a savings of 55 percent was obtained on the systems using ozone. A major problem experienced in the use of ozone for cooling tower applications was the difficulty of accurate concentration measurements. The ability to control the operational characteristics relies on easily and accurately determined concentration levels. Present methods of detection are subject to inaccuracies because of interfering materials and the rapid destruction of the ozone.

  2. Effect of ozonation on the reactivity of lignocellulose substrates in enzymatic hydrolyses to sugars

    Science.gov (United States)

    Ben'ko, E. M.; Manisova, O. R.; Lunin, V. V.

    2013-07-01

    The efficiency of pre-treatment of aspen wood with ozone for subsequent enzymatic hydrolysis into sugars is determined by the amount of absorbed ozone. The ozone absorption rate depended on the water content in the sample being ozonized and was maximum at a relative humidity of wood of ˜40%. As a result of ozone pre-treatment, the initial rate of the enzymatic hydrolysis of wood under the action of a cellulase complex increased eightfold, and the maximum yield of sugars increased tenfold depending on the ozone dose. The ozonation at ozone doses of more than 3 mol/PPU (phenylpropane structural unit of lignin) led to a decrease in the yield of sugars because of the oxidative destruction of cellulose and hemicellulose. The alkaline ozonation in 2 and 12% NaOH was inefficient because of the accompanying oxidation of carbohydrates and considerably decreased the yield of sugars.

  3. The Effects of Acid Passivation, Tricresyl Phosphate Presoak, and UV/Ozone Treatment on the Tribology of Perfluoropolyether-Lubricated 440C Stainless Steel Couples

    Science.gov (United States)

    Shogrin, Bradley A.; Jones, William R., Jr.; Herrera-Fierro, Pilar; Jansen, Mark J.

    2001-01-01

    The boundary-lubrication performance of two perfluoropolyether (PFPE) thin films in the presence of passivated 440C stainless steel is presented. The study used a standard ball on disk (BoD) tribometer in dry nitrogen and a vacuum spiral orbit tribometer (SOT). Stainless steel surfaces were passivated with one of four techniques: high and low temperature chromic acid bath, a tricresyl phosphate (TCP) soak, or UV/Ozone treated for 15 min. After passivation, each BoD disk had a 400A film of Krytox 16256 (PFPE) applied to it. The lifetimes of these films were quantified by measuring the number of sliding cycles before an increase in friction occurred. The lubricated lifetime of the 440C couple was not altered as a result of the various passivation techniques. The resulting surface chemistry of each passivation technique was examined using X-ray photoelectron spectroscopy (XPS). The SOT was used to examine the effects of the TCP treatment on the lubricated lifetime of another PFPE, Brayco 815Z, under rolling conditions. None of the passivation techniques were found to dramatically increase the oxide film thickness or lubricated lifetimes.

  4. Effect of ozone gas processing on physical and chemical properties ...

    African Journals Online (AJOL)

    Purpose: To investigate the effects of ozone treatment on chemical and physical properties of wheat (Triticum aestivum L.) gluten, glutenin and gliadin. Methods: Wheat proteins isolated from wheat flour were treated with ozone gas. The physical and chemical properties of gluten proteins were investigated after treatment ...

  5. The Effect of Ozone and Zeolite Concentration to the Performance of the Treatment of Wastewater Containing Heavy Metal Using Flotation Process

    Directory of Open Access Journals (Sweden)

    Eva Karamah

    2010-10-01

    Full Text Available Industrial wastewater which contains heavy metal cannot be disposed to the environment directly, due to its toxicity. In this research, separation of metal from wastewater was conducted by sorptive flotation method, using Lampung natural zeolite as bonding agent. The most common diffuser used in the flotation process is air or oxygen. In this research, ozone is used as diffuser because it is a stronger oxidant and more dissolvable in water than oxygen. Besides, ozone is a coagulant aid and disinfectant. With ozone as diffuser, it is expected that the process become faster with higher efficiency. This research was conducted to determine ozone effectiveness as diffuser, compared with other diffuser, and also to determine optimum concentration and effectiveness of zeolite in flotation of iron, nickel and copper. The research result shows that separation of iron with air diffuser is 90.8%, air-oxygen diffuser is 95.7%, air-ozone (from air diffuser is 99.7%, and air-ozone (from oxygen diffuser is 99.7%. Natural zeolite is effective as bonding agent with optimum concentration equal to 2 gram/liter, producing separation percentage for iron equal to 99.70%, copper equal to 88.98% and Nickel equal to 98.46%.

  6. Effects of ozone and ozone/peroxide on trace organic contaminants and NDMA in drinking water and water reuse applications.

    Science.gov (United States)

    Pisarenko, Aleksey N; Stanford, Benjamin D; Yan, Dongxu; Gerrity, Daniel; Snyder, Shane A

    2012-02-01

    An ozone and ozone/peroxide oxidation process was evaluated at pilot scale for trace organic contaminant (TOrC) mitigation and NDMA formation in both drinking water and water reuse applications. A reverse osmosis (RO) pilot was also evaluated as part of the water reuse treatment train. Ozone/peroxide showed lower electrical energy per order of removal (EEO) values for TOrCs in surface water treatment, but the addition of hydrogen peroxide increased EEO values during wastewater treatment. TOrC oxidation was correlated to changes in UV(254) absorbance and fluorescence offering a surrogate model for predicting contaminant removal. A decrease in N-nitrosodimethylamine (NDMA) formation potential (after chloramination) was observed after treatment with ozone and ozone/peroxide. However, during spiking experiments with surface water, ozone/peroxide achieved limited destruction of NDMA, while in wastewaters net direct formation of NDMA of 6-33 ng/L was observed after either ozone or ozone/peroxide treatment. Once formed during ozonation, NDMA passed through the subsequent RO membranes, which highlights the significance of the potential for direct NDMA formation during oxidation in reuse applications. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Treatment of foods with 'soft-electrons' (low-energy electrons)

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Toru [Japan International Research Center for Agricultural Sciences (JIRCAS), Tsukuba, Ibaraki (Japan); Todoriki, Setsuko [National Food Research Institute (NFRI), Tsukuba, Ibaraki (Japan)

    2003-02-01

    Electrons with energies of 300 keV or lower were defined as soft-electrons'. Soft-electrons can eradicate microorganisms residing on the surface of grains, pulses, spices, dehydrated vegetables, tea leaves and seeds, and reduce their microbial loads to levels lower than 10 CFU/g with little quality deterioration. Soft-electrons can inactivate insect pests infesting grains and pulses and inhibit sprouting of potatoes. (author)

  8. Treatment of foods with 'soft-electrons' (low-energy electrons)

    International Nuclear Information System (INIS)

    Hayashi, Toru; Todoriki, Setsuko

    2003-01-01

    Electrons with energies of 300 keV or lower were defined as soft-electrons'. Soft-electrons can eradicate microorganisms residing on the surface of grains, pulses, spices, dehydrated vegetables, tea leaves and seeds, and reduce their microbial loads to levels lower than 10 CFU/g with little quality deterioration. Soft-electrons can inactivate insect pests infesting grains and pulses and inhibit sprouting of potatoes. (author)

  9. Clinical implementation of total skin electron irradiation treatment with a 6 MeV electron beam in high-dose total skin electron mode

    International Nuclear Information System (INIS)

    Lucero, J. F.; Rojas, J. I.

    2016-01-01

    Total skin electron irradiation (TSEI) is a special treatment technique offered by modern radiation oncology facilities, given for the treatment of mycosis fungoides, a rare skin disease, which is type of cutaneous T-cell lymphoma [1]. During treatment the patient’s entire skin is irradiated with a uniform dose. The aim of this work is to present implementation of total skin electron irradiation treatment using IAEA TRS-398 code of practice for absolute dosimetry and taking advantage of the use of radiochromic films.

  10. Clinical implementation of total skin electron irradiation treatment with a 6 MeV electron beam in high-dose total skin electron mode

    Energy Technology Data Exchange (ETDEWEB)

    Lucero, J. F., E-mail: fernando.lucero@hoperadiotherapy.com.gt [Universidad Nacional de Costa Rica, Heredia (Costa Rica); Hope International, Guatemala (Guatemala); Rojas, J. I., E-mail: isaac.rojas@siglo21.cr [Centro Médico Radioterapia Siglo XXI, San José (Costa Rica)

    2016-07-07

    Total skin electron irradiation (TSEI) is a special treatment technique offered by modern radiation oncology facilities, given for the treatment of mycosis fungoides, a rare skin disease, which is type of cutaneous T-cell lymphoma [1]. During treatment the patient’s entire skin is irradiated with a uniform dose. The aim of this work is to present implementation of total skin electron irradiation treatment using IAEA TRS-398 code of practice for absolute dosimetry and taking advantage of the use of radiochromic films.

  11. Integrating Organ Motion and Setup Uncertainty into Optimization of Modulated Electron Beam Treatment of Breast Cancer

    National Research Council Canada - National Science Library

    Pawlicki, Todd

    2003-01-01

    ... of modulated electron radiotherapy (MERT) treatment of the breast. The premise is that MERT treatments will deliver a more conformal dose to the breast while minimizing the dose to normal tissues over conventional photon techniques...

  12. The stratospheric ozone and the ozone layer

    International Nuclear Information System (INIS)

    Zea Mazo, Jorge Anibal; Leon Aristizabal Gloria Esperanza; Eslava Ramirez Jesus Antonio

    2000-01-01

    An overview is presented of the principal characteristics of the stratospheric ozone in the Earth's atmosphere, with particular emphasis on the tropics and the ozone hole over the poles. Some effects produced in the atmosphere as a consequence of the different human activities will be described, and some data on stratospheric ozone will be shown. We point out the existence of a nucleus of least ozone in the tropics, stretching from South America to central Africa, with annual mean values less than 240 DU, a value lower than in the middle latitudes and close to the mean values at the South Pole. The existence of such a minimum is confirmed by mean values from measurements made on satellites or with earthbound instruments, for different sectors in Colombia, like Medellin, Bogota and Leticia

  13. Abscisic acid protects bean leaves from ozone-induced phytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Fletcher, R.A.; Adedipe, N.O.; Ormrod, D.P.

    1972-01-01

    Abscisic acid treatment of primary bean leaves caused a partial closure of stomates and thus considerably reduced the phytotoxicity of ozone. The symptoms of ozone-induced phytotoxicity in the water-treated leaves are a marked decrease in chlorophyll and slight decreases in the levels of protein and RNA. The evidence indicates that ozone injury to leaves is not metabolically related to normal leaf senescence.

  14. Ozone therapy in periodontics.

    Science.gov (United States)

    Gupta, G; Mansi, B

    2012-02-22

    Gingival and Periodontal diseases represent a major concern both in dentistry and medicine. The majority of the contributing factors and causes in the etiology of these diseases are reduced or treated with ozone in all its application forms (gas, water, oil). The beneficial biological effects of ozone, its anti-microbial activity, oxidation of bio-molecules precursors and microbial toxins implicated in periodontal diseases and its healing and tissue regeneration properties, make the use of ozone well indicated in all stages of gingival and periodontal diseases. The primary objective of this article is to provide a general review about the clinical applications of ozone in periodontics. The secondary objective is to summarize the available in vitro and in vivo studies in Periodontics in which ozone has been used. This objective would be of importance to future researchers in terms of what has been tried and what the potentials are for the clinical application of ozone in Periodontics.

  15. Treatment of surfaces with low-energy electrons

    Science.gov (United States)

    Frank, L.; Mikmeková, E.; Lejeune, M.

    2017-06-01

    Electron-beam-induced deposition of various materials from suitable precursors has represented an established branch of nanotechnology for more than a decade. A specific alternative is carbon deposition on the basis of hydrocarbons as precursors that has been applied to grow various nanostructures including masks for subsequent technological steps. Our area of study was unintentional electron-beam-induced carbon deposition from spontaneously adsorbed hydrocarbon molecules. This process traditionally constitutes a challenge for scanning electron microscopy practice preventing one from performing any true surface studies outside an ultrahigh vacuum and without in-situ cleaning of samples, and also jeopardising other electron-optical devices such as electron beam lithographs. Here we show that when reducing the energy of irradiating electrons sufficiently, the e-beam-induced deposition can be converted to e-beam-induced release causing desorption of hydrocarbons and ultimate cleaning of surfaces in both an ultrahigh and a standard high vacuum. Using series of experiments with graphene samples, we demonstrate fundamental features of e-beam-induced desorption and present results of checks for possible radiation damage using Raman spectroscopy that led to optimisation of the electron energy for damage-free cleaning. The method of preventing carbon contamination described here paves the way for greatly enhanced surface sensitivity of imaging and substantially reduced demands on vacuum systems for nanotechnological applications.

  16. Treatment of surfaces with low-energy electrons

    Energy Technology Data Exchange (ETDEWEB)

    Frank, L., E-mail: ludek@isibrno.cz [Institute of Scientific Instruments of the CAS, v.v.i., Královopolská 147, 61264 Brno (Czech Republic); Mikmeková, E. [Institute of Scientific Instruments of the CAS, v.v.i., Královopolská 147, 61264 Brno (Czech Republic); FEI Company, Achtseweg Noord 5, 5651 GG Eindhoven (Netherlands); Lejeune, M. [LPMC – Faculte des Sciences d’Amiens, Universite de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens Cedex 2 (France)

    2017-06-15

    Highlights: • Using proper irradiation parameters, adsorbed hydrocarbons are released from surfaces. • Slow electrons remove hydrocarbons instead of depositing carbon. • Prolonged irradiation with very slow electrons does not create defects in graphene. - Abstract: Electron-beam-induced deposition of various materials from suitable precursors has represented an established branch of nanotechnology for more than a decade. A specific alternative is carbon deposition on the basis of hydrocarbons as precursors that has been applied to grow various nanostructures including masks for subsequent technological steps. Our area of study was unintentional electron-beam-induced carbon deposition from spontaneously adsorbed hydrocarbon molecules. This process traditionally constitutes a challenge for scanning electron microscopy practice preventing one from performing any true surface studies outside an ultrahigh vacuum and without in-situ cleaning of samples, and also jeopardising other electron-optical devices such as electron beam lithographs. Here we show that when reducing the energy of irradiating electrons sufficiently, the e-beam-induced deposition can be converted to e-beam-induced release causing desorption of hydrocarbons and ultimate cleaning of surfaces in both an ultrahigh and a standard high vacuum. Using series of experiments with graphene samples, we demonstrate fundamental features of e-beam-induced desorption and present results of checks for possible radiation damage using Raman spectroscopy that led to optimisation of the electron energy for damage-free cleaning. The method of preventing carbon contamination described here paves the way for greatly enhanced surface sensitivity of imaging and substantially reduced demands on vacuum systems for nanotechnological applications.

  17. Quantum-mechanical treatment of an electron undergoing synchrotron radiation.

    Science.gov (United States)

    White, D.

    1972-01-01

    The problem of an electron moving perpendicular to an intense magnetic field is approached from the framework of quantum mechanics. A numerical solution to the related rate equations describing the probabilities of occupation of the electron's energy states is put forth along with the expected errors involved. The quantum-mechanical approach is found to predict a significant amount of energy broadening with time for an initially monoenergetic electron beam entering a region of an intense magnetic field as long as the product of initial energy and magnetic field is of order 50 MG BeV or larger.

  18. Treatment of surfaces with low-energy electrons

    Czech Academy of Sciences Publication Activity Database

    Frank, Luděk; Mikmeková, Eliška; Lejeune, M.

    2017-01-01

    Roč. 407, JUN 15 (2017), s. 105-108 ISSN 0169-4332 R&D Projects: GA TA ČR(CZ) TE01020118; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : Low- energy electrons * Electron beam induced release * Graphene * Ultimate cleaning of surfaces Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Nano-processes (applications on nano-scale) Impact factor: 3.387, year: 2016

  19. Effects of Single and Multifactor Treatments with Elevated Temperature, CO2 and Ozone on Oilseed Rape and Barley

    DEFF Research Database (Denmark)

    Clausen, Sabine Karin; Frenck, Georg; van der Linden, Leon Gareth

    2011-01-01

    We investigated the effect of elevated [CO2], [O3] and temperature on plant productivity and if these climate factors interacted with each other in multifactor treatments. The climate effects were studied in 14 different cultivars/lines of European spring oilseed rape (Brassica napus L.) and spring...... barley (Hordeum vulgare L.). Seven genotypes of each species were cultivated in six single- and multifactor treatments with ambient or elevated CO2 (385 ppm and 700 ppm), O3 (20 ppb and 60 ppb) and temperature (12/19 °C and 17/24 °C). Growth and production parameters were measured. Elevated CO2 increased....... A significantly decreased yield and thousand grain weight was also seen in barley due to elevated O3. The multifactor combination of elevated CO2, O3 and temperature showed a decrease in growth and production in the two species, though not statistically significant for all parameters. This trend suggests...

  20. SMM mesospheric ozone measurements

    Science.gov (United States)

    Aikin, A. C.

    1990-01-01

    The main objective was to understand the secular and seasonal behavior of ozone in the lower mesosphere, 50 to 70 km. This altitude region is important in understanding the factors which determine ozone behavior. A secondary objective is the study of stratospheric ozone in the polar regions. Use is made of results from the SBUV satellite borne instrument. In the Arctic the interaction between chlorine compounds and low molecular weight hydrocarbons is studied. More than 30,000 profiles were obtained using the UVSP instrument on the SMM spacecraft. Several orbits of ozone data per day were obtained allowing study of the current rise in solar activity from the minimum until the present. Analysis of Nimbus 7 SBUV data in Antarctic spring indicates that ozone is depleted within the polar vortex relative to ozone outside the vortex. This depletion confirms the picture of ozone loss at altitudes where polar stratospheric clouds exist. In addition, there is ozone loss above the cloud level indicating that there is another mechanism in addition to ozone loss initiated by heterogeneous chlorine reactions on cloud particles.

  1. The effect of heat- or ultra violet ozone-treatment of titanium on complement deposition from human blood plasma.

    Science.gov (United States)

    Linderbäck, Paula; Harmankaya, Necati; Askendal, Agneta; Areva, Sami; Lausmaa, Jukka; Tengvall, Pentti

    2010-06-01

    Titanium (Ti) is a well known metallic biomaterial extensively used in dental, orthopaedic-, and occasionally also in blood contacting applications. It integrates well to bone and soft tissues, and is shown upon blood plasma contact to activate the intrinsic pathway of coagulation and bind complement factor 3b. The material properties depend largely on those of the nm-thick dense layer of TiO(2) that becomes rapidly formed upon contact with air and water. The spontaneously formed amorphous Ti-oxide has a pzc approximately 5-6 and its water solubility is at the order of 1-2 micromolar. It is often subjected to chemical- and heat treatments in order to increase the anatase- and rutile crystallinity, to modify the surface topography and to decrease the water solubility. In this work, we prepared sol-gel derived titanium and smooth PVD titanium surfaces, and analysed their oxide and protein deposition properties in human blood plasma before and after annealing at 100-500 degrees C or upon UVO-treatment for up to 96 hours. The blood plasma results show that complement deposition vanished irreversibly after heat treatment at 250-300 degrees C for 30 minutes or after UVO exposure for 24 hours or longer. XPS and infrared spectroscopy indicated change of surface water/hydroxyl binding upon the heat- and UVO treatments, and increased Ti oxidation. XRD analysis confirmed an increased crystallinity and both control (untreated) and annealed smooth titanium displayed low XRD-signals indicating some nanocrystallinity, with predominantly anatase phase. The current results show that the behaviour of titanium dioxide in blood contact can be controlled through relatively simple means, such as mild heating and illumination in UV-light, which both likely irreversibly change the stoichiometry and structure of the outmost layers of titanium dioxide and its OH/H(2)O binding characteristics. (c) 2010 Elsevier Ltd. All rights reserved.

  2. Study on the Ozonation of Organic Wastes (1)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Hong; Kang, Il Sik; Hong, Dae Seok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    Ozone is often used in combination with H{sub 2}O{sub 2}, UV, peroxides, and the catalyst. These combined processes have the purpose to increase OH radicals, so this combination process is called the advanced oxidation process (AOP, Advanced Oxidation Process). In this study, the possibility of the oxidation treatment of LSC Cocktail solution by using a combination of ozone and hydrogen peroxide was investigated. The addition of a suitable amount of hydrogen peroxide increases the efficiency of the oxidation process during ozonation of the organic materials. But on the contrary, the excess addition of hydrogen they can play a role as a scavenger consuming the hydroxyl radicals generated during the ozonation process. So it is very important to find the amount of volume of hydrogen peroxide. The efficiency of oxidation treatment of organic materials is greatly depended on the properties of liquid waste (pH, concentration and chemical type of organics), the process temperature, the flow rate (waste and ozone gas), the ozone concentration, the hydrogen peroxide concentration and the presence or absence of scavengers. In this study, by using an ozone contactor (hydrophobic hollow fiber membrane type), the basic experiments were carried out to evaluate the applicability of ozonation to the organic wastes. First of all, the oxidation treatment was evaluated by ozone alone, and secondly was evaluated according to the changes of the amount of hydrogen peroxide and a pH of wastes.

  3. Study on the Ozonation of Organic Wastes (1)

    International Nuclear Information System (INIS)

    Kim, Ki Hong; Kang, Il Sik; Hong, Dae Seok

    2014-01-01

    Ozone is often used in combination with H 2 O 2 , UV, peroxides, and the catalyst. These combined processes have the purpose to increase OH radicals, so this combination process is called the advanced oxidation process (AOP, Advanced Oxidation Process). In this study, the possibility of the oxidation treatment of LSC Cocktail solution by using a combination of ozone and hydrogen peroxide was investigated. The addition of a suitable amount of hydrogen peroxide increases the efficiency of the oxidation process during ozonation of the organic materials. But on the contrary, the excess addition of hydrogen they can play a role as a scavenger consuming the hydroxyl radicals generated during the ozonation process. So it is very important to find the amount of volume of hydrogen peroxide. The efficiency of oxidation treatment of organic materials is greatly depended on the properties of liquid waste (pH, concentration and chemical type of organics), the process temperature, the flow rate (waste and ozone gas), the ozone concentration, the hydrogen peroxide concentration and the presence or absence of scavengers. In this study, by using an ozone contactor (hydrophobic hollow fiber membrane type), the basic experiments were carried out to evaluate the applicability of ozonation to the organic wastes. First of all, the oxidation treatment was evaluated by ozone alone, and secondly was evaluated according to the changes of the amount of hydrogen peroxide and a pH of wastes

  4. Degradation of sulfamethoxazole using ozone and chlorine dioxide - Compound-specific stable isotope analysis, transformation product analysis and mechanistic aspects.

    Science.gov (United States)

    Willach, Sarah; Lutze, Holger V; Eckey, Kevin; Löppenberg, Katja; Lüling, Michelle; Terhalle, Jens; Wolbert, Jens-Benjamin; Jochmann, Maik A; Karst, Uwe; Schmidt, Torsten C

    2017-10-01

    The sulfonamide antibiotic sulfamethoxazole (SMX) is a widely detected micropollutant in surface and groundwaters. Oxidative treatment with e.g. ozone or chlorine dioxide is regularly applied for disinfection purposes at the same time exhibiting a high potential for removal of micropollutants. Especially for nitrogen containing compounds such as SMX, the related reaction mechanisms are largely unknown. In this study, we systematically investigated reaction stoichiometry, product formation and reaction mechanisms in reactions of SMX with ozone and chlorine dioxide. To this end, the neutral and anionic SMX species, which may occur at typical pH-values of water treatment were studied. Two moles of chlorine dioxide and approximately three moles of ozone were consumed per mole SMX degraded. Oxidation of SMX with ozone and chlorine dioxide leads in both cases to six major transformation products (TPs) as revealed by high-resolution mass spectrometry (HRMS). Tentatively formulated TP structures from other studies could partly be confirmed by compound-specific stable isotope analysis (CSIA). However, for one TP, a hydroxylated SMX, it was not possible by HRMS alone to identify whether hydroxylation occurred at the aromatic ring, as suggested in literature before, or at the anilinic nitrogen. By means of CSIA and an analytical standard it was possible to identify sulfamethoxazole hydroxylamine unequivocally as one of the TPs of the reaction of SMX with ozone as well as with chlorine dioxide. H-abstraction and electron transfer at the anilinic nitrogen are suggested as likely initial reactions of ozone and chlorine dioxide, respectively, leading to its formation. Oxidation of anionic SMX with ozone did not show any significant isotopic fractionation whereas the other reactions studied resulted in a significant carbon isotope fractionation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Current status of electron beam treatment of flue gas in China

    International Nuclear Information System (INIS)

    Wang Zhiguang

    2006-01-01

    Fossil resource especially coal will remain the main energy resource in China over the next 3 ∼4 decades. Pollution of flue gas from fossil power station is one problem being desiderated to solve since 1990's. Electron beam treatment of flue gas as an advanced technique has been developed and used by some institutes and industries in China. The current status of flue gas treatment using electron beam and the development of electron accelerator in China are reviewed. (author)

  6. On the OSL curve shape and preheat treatment of electronic components from portable electronic devices

    DEFF Research Database (Denmark)

    Woda, Clemens; Greilich, Steffen; Beerten, Koen

    2010-01-01

    The shape of the OSL decay curve and the effect of longer time delays between accidental exposure and readout of alumina-rich electronic components from portable electronic devices are investigated. The OSL decay curve follows a hyperbolic decay function, which is interpreted as an approximation ...

  7. Ozone and Water Stress: Effects on the Behaviour of Two White Clover Biotypes

    Directory of Open Access Journals (Sweden)

    Massimo Fagnano

    Full Text Available ozone pollution, water stress, stomata conductance, ozone uptake, clover, OTC.Ozone is a strong oxidizing pollutant which derives by alteration of the photolytic NOx cycle and it accumulates in the troposphere spreading in rural areas and therefore determining injuries on natural vegetation and crops. Since its penetration occurs mainly through stomata, all factors which alter plant-atmosphere relations could be able to modify plant response to ozone. Interaction between ozone and water stress in Mediterranean environment was studied on ozone resistant and sensitive biotypes of white clover, which were grown in charcoal filtered and notfiltered Open Top Chambers in factorial combination with different levels of water supply. Measurements of biomass, leaf area and stomatal conductance were made during the growth period. Ozone injuries were estimated as not-filtered/filtered OTC yield ratio; the stomatal flux of ozone was estimated multiplying stomata conductance x diffusivity ratio between ozone and water vapour (0.613 x ozone hourly concentrations. The hourly values of ozone uptake were cumulated throughout the cropping periods of the two years. In the sensitive biotype, water stress reduced yield losses due to ozone from 38% to 22%, as well as yield losses due to water stress were reduced by the presence of ozone from 43% to 29%, while no interaction between ozone and water stress was observed in the resistant biotype. Biomass yield losses of the sensitive biotype were strictly correlated to cumulated ozone uptake (R2 = 0.99, while biomass yield losses of the resistant biotype were not affected by the ozone fluxes variations created by the treatments. Flux based models could better estimate yield losses due to ozone in Mediterranean environments in which other stresses could be contemporary present; therefore, the new European directives might replace the actual thresholds based

  8. Treatment of diazo dye C.I. Reactive Black 5 in aqueous solution by combined process of interior microelectrolysis and ozonation.

    Science.gov (United States)

    Guo, Xiaoyan; Cai, Yaping; Wei, Zhongbo; Hou, Haifeng; Yang, Xi; Wang, Zunyao

    2013-01-01

    Interior microelectrolysis (IM) as a pretreatment process was effective to treat Reactive Black 5 (RB5) in this study. The removal rates of chemical oxygen demand (COD), total organic carbon (TOC) and color were 46.05, 39.99 and 98.77%, respectively, when this process was conducted under the following optimal conditions: the volumetric ratio between iron scraps and active carbon (AC) (V(Fe)/V(C)) 1.0, pH 2.0, aeration dosage 0.6 L/min, and reaction time 100 min. Contaminants could be further removed by ozonation. After subsequent ozonation for 200 min, the solution could be completely decolorized, and the COD and TOC removal rates were up to 77.78 and 66.51%, respectively. In addition, acute toxicity tests with Daphnia magna showed that pretreatment by IM generated effluents that were more toxic when compared with the initial wastewater, and the toxicity was reduced after subsequent ozonation.

  9. Electron-impact ionization of atomic hydrogen: dynamical variational treatment

    Energy Technology Data Exchange (ETDEWEB)

    Defrance, P.; Lecointre, J. [Institute of Condensed Matter and Nanosciences, Universite Catholique de Louvain, Louvain-la-Neuve (Belgium); Kereselidze, T.; Machavariani, Z.S. [Department of Exact and Natural Sciences, Tbilissi State University, Tbilissi (Georgia)

    2011-10-15

    A simple and straightforward calculating scheme is proposed for electron-impact single and multiple ionization of atoms. The method is based on the application of the Hulthen-Kohn dynamical variational principle. An effective charge seen by the scattered electron is determined for a certain type of trial wave functions mathematically in a rigorous way excluding any empirical assumptions. Validity of the elaborated approach is assessed by calculating triply differential cross section (TDCS) for electron-impact ionization of hydrogen. It is shown that, inclusion of the effective charge into the calculation reduces height of a 'binary peak' in comparison with the first Born approximation result. The height of a 'recoil peak' depends on the sign of the effective charge. The calculated TDCS are compared with the available experimental data and with the results of sophisticated theories and agreement is found. (authors)

  10. LANDFILL LEACHATES PRETREATMENT BY OZONATION

    Directory of Open Access Journals (Sweden)

    Jacek Leszczyński

    2016-06-01

    Full Text Available In this paper, the application of ozonation processes for stabilized landfill leachate treatment was investigated. The leachate came from a municipal sanitary landfill located nearby Bielsk Podlaski. The average values of its main parameters were: pH 8.23; COD 870 mgO2/dm3; BOD 90 mgO2/dm3; NH4+ 136.2 mgN/dm3; UV254 absorbance 0.312 and turbidity 14 NTU. The ozone dosages used were in the range of 115.5 to 808.5 mgO3/dm3 of the leachate. The maximum COD, color and UV254 absorbance removal wa.5 mgO3/dm3. After oxidation, the ratio of BOD/COD was increased from 0.1 up to 0.23.

  11. Rapid Removal of Tetrabromobisphenol A by Ozonation in Water: Oxidation Products, Reaction Pathways and Toxicity Assessment.

    Directory of Open Access Journals (Sweden)

    Ruijuan Qu

    Full Text Available Tetrabromobisphenol A (TBBPA is one of the most widely used brominated flame retardants and has attracted more and more attention. In this work, the parent TBBPA with an initial concentration of 100 mg/L was completely removed after 6 min of ozonation at pH 8.0, and alkaline conditions favored a more rapid removal than acidic and neutral conditions. The presence of typical anions and humic acid did not significantly affect the degradation of TBBPA. The quenching test using isopropanol indicated that direct ozone oxidation played a dominant role during this process. Seventeen reaction intermediates and products were identified using an electrospray time-of-flight mass spectrometer. Notably, the generation of 2,4,6-tribromophenol was first observed in the degradation process of TBBPA. The evolution of reaction products showed that ozonation is an efficient treatment for removal of both TBBPA and intermediates. Sequential transformation of organic bromine to bromide and bromate was confirmed by ion chromatography analysis. Two primary reaction pathways that involve cleavage of central carbon atom and benzene ring cleavage concomitant with debromination were thus proposed and further justified by calculations of frontier electron densities. Furthermore, the total organic carbon data suggested a low mineralization rate, even after the complete removal of TBBPA. Meanwhile, the acute aqueous toxicity of reaction solutions to Photobacterium Phosphoreum and Daphnia magna was rapidly decreased during ozonation. In addition, no obvious difference in the attenuation of TBBPA was found by ozone oxidation using different water matrices, and the effectiveness in natural waters further demonstrates that ozonation can be adopted as a promising technique to treat TBBPA-contaminated waters.

  12. Rapid Removal of Tetrabromobisphenol A by Ozonation in Water: Oxidation Products, Reaction Pathways and Toxicity Assessment

    Science.gov (United States)

    Wang, Xinghao; Huang, Qingguo; Lu, Junhe; Wang, Liansheng; Wang, Zunyao

    2015-01-01

    Tetrabromobisphenol A (TBBPA) is one of the most widely used brominated flame retardants and has attracted more and more attention. In this work, the parent TBBPA with an initial concentration of 100 mg/L was completely removed after 6 min of ozonation at pH 8.0, and alkaline conditions favored a more rapid removal than acidic and neutral conditions. The presence of typical anions and humic acid did not significantly affect the degradation of TBBPA. The quenching test using isopropanol indicated that direct ozone oxidation played a dominant role during this process. Seventeen reaction intermediates and products were identified using an electrospray time-of-flight mass spectrometer. Notably, the generation of 2,4,6-tribromophenol was first observed in the degradation process of TBBPA. The evolution of reaction products showed that ozonation is an efficient treatment for removal of both TBBPA and intermediates. Sequential transformation of organic bromine to bromide and bromate was confirmed by ion chromatography analysis. Two primary reaction pathways that involve cleavage of central carbon atom and benzene ring cleavage concomitant with debromination were thus proposed and further justified by calculations of frontier electron densities. Furthermore, the total organic carbon data suggested a low mineralization rate, even after the complete removal of TBBPA. Meanwhile, the acute aqueous toxicity of reaction solutions to Photobacterium Phosphoreum and Daphnia magna was rapidly decreased during ozonation. In addition, no obvious difference in the attenuation of TBBPA was found by ozone oxidation using different water matrices, and the effectiveness in natural waters further demonstrates that ozonation can be adopted as a promising technique to treat TBBPA-contaminated waters. PMID:26430733

  13. Alignment creation by elastic electron scattering. A quantum treatment

    International Nuclear Information System (INIS)

    Csanak, G.; Kilcrease, D.P.; Fursa, D.V.; Bray, I.

    2004-01-01

    Alignment creation by elastic heavy particle scattering has been studied by many authors. A formula for the alignment creation cross section by elastic scattering is obtained by quantum-mechanical methods. The formula obtained differs from the analogous formula relevant for inelastic electron scattering. In the case of a J=1 to J=1 transition according to the inelastic formula, the alignment created is proportional to the quantity σ (1) - σ (0) where σ (M) is the excitation cross section of the M magnetic sublevel and thus σ (1) = (σ 1-1 + σ 10 + σ 11 )/3 and σ (0) = (σ 0-1 +σ 00 + σ 01 )/3 where σ MM' refers to the cross section of the electron impact induced M' to M transition. In the elastic scattering alignment creation formula obtained in the case of a J=1 to J=1 elastic scattering, the alignment created is proportional to the quantity q(1) - q(0) where q(1) σ (1) - σ 11 /3 and q(0) = σ 00 /3. Thus in obtaining q(M), the elastic scattering cross section by the M magnetic sublevel, σ MM' , is subtracted. This derivation considered only direct scattering, i.e. the incident electron was considered distinguishable from the target electrons. (Y.Kazumata)

  14. Pollution Control Using Ozone

    DEFF Research Database (Denmark)

    2017-01-01

    This invention relates to a method for cleaning air comprising one or more pollutants, the method comprising contacting the air with thermal decompositions products of ozone.......This invention relates to a method for cleaning air comprising one or more pollutants, the method comprising contacting the air with thermal decompositions products of ozone....

  15. The pollution by ozone

    International Nuclear Information System (INIS)

    1997-09-01

    Air pollution by ozone is increasing in spite of several points to reduce it. If the process of ozone formation are complex, the sources of this pollution are well known: first, mobile sources with automobiles (49%), boats , trains and planes (13%), then are following paints and solvents(18%), thermal power plants(11%), and finally industry processing with 5%. (N.C.)

  16. Improvement in Dissolution of Cotton Pulp with Ionic liquid by the Electron Beam Treatment

    International Nuclear Information System (INIS)

    Lee, Won Sil; Jung, Wong Gi; Sung, Yong Joo

    2013-01-01

    Electron beam treatment was applied for improving dissolution of cotton pulp with ionic liquids. Two ionic liquids, 1-allyl-3-methylimidazolium chloride ([Amim]Cl]: AC) and 1,3-dimethylimidzolium methlphosphite ([Dmim][(MeO)(H)PO2]: Me) were used for this experiment. Treatment with electron beams up to dose of 400 kGy resulted in the increase of hot water extract and alkali extract of cotton pulp and the great reduction in the molecular weight of cellulose. For the dissolution of cotton pulp with two ionic liquids, the electron beam treated samples showed faster dissolution. The dissolved cellulose with Me ionic liquid were regenerated with Acetonitrile and the structure of regenerated cellulose showed distinct difference depending on the electron beam treatment. Those results provide the electron beam pre-treatment could be applied as an energy efficient and environmentally benign method to increase the dissolution of cotton pulp with ionic liquids

  17. Root growth and physiology of potted and field-grown trembling aspen exposed to tropospheric ozone

    Science.gov (United States)

    M.D. Coleman; R.E. Dickson; J.G. Isebrands; D.F. Karnosky

    1996-01-01

    We studied root growth and respiration of potted plants and field-grown aspen trees (Populus tremuloides Michx.) exposed to ambient or twice-ambient ozone. Root dry weight of potted plants decreased up to 45% after 12 weeks of ozone treatment, and root system respiration decreased by 27%. The ozone-induced decrease in root system respiration of...

  18. Estonian total ozone climatology

    Directory of Open Access Journals (Sweden)

    K. Eerme

    Full Text Available The climatological characteristics of total ozone over Estonia based on the Total Ozone Mapping Spectrometer (TOMS data are discussed. The mean annual cycle during 1979–2000 for the site at 58.3° N and 26.5° E is compiled. The available ground-level data interpolated before TOMS, have been used for trend detection. During the last two decades, the quasi-biennial oscillation (QBO corrected systematic decrease of total ozone from February–April was 3 ± 2.6% per decade. Before 1980, a spring decrease was not detectable. No decreasing trend was found in either the late autumn ozone minimum or in the summer total ozone. The QBO related signal in the spring total ozone has an amplitude of ± 20 DU and phase lag of 20 months. Between 1987–1992, the lagged covariance between the Singapore wind and the studied total ozone was weak. The spring (April–May and summer (June–August total ozone have the best correlation (coefficient 0.7 in the yearly cycle. The correlation between the May and August total ozone is higher than the one between the other summer months. Seasonal power spectra of the total ozone variance show preferred periods with an over 95% significance level. Since 1986, during the winter/spring, the contribution period of 32 days prevails instead of the earlier dominating 26 days. The spectral densities of the periods from 4 days to 2 weeks exhibit high interannual variability.

    Key words. Atmospheric composition and structure (middle atmosphere – composition and chemistry; volcanic effects – Meteorology and atmospheric dynamics (climatology

  19. Electron Beam Welding of Duplex Steels with using Heat Treatment

    Science.gov (United States)

    Schwarz, Ladislav; Vrtochová, Tatiana; Ulrich, Koloman

    2010-01-01

    This contribution presents characteristics, metallurgy and weldability of duplex steels with using concentrated energy source. The first part of the article describes metallurgy of duplex steels and the influence of nitrogen on their solidification. The second part focuses on weldability of duplex steels with using electron beam aimed on acceptable structure and corrosion resistance performed by multiple runs of defocused beam over the penetration weld.

  20. Bubble-free ozone addition through ceramic membranes for wet-oxidative waste water treatment; Blasenfreier Ozoneintrag durch keramische Membranen zur nassoxidativen Abwasserbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Janknecht, P.; Wilderer, P.A. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl und Pruefamt fuer Wasserguete- und Abfallwirtschaft

    1999-07-01

    A prerequisite for successful wet oxidation is very accurately tuned and carefully monitored process control. In the alternative, a decline in water quality is actually possible. In particular, earlier studies in the ozonification of landfill leachate encountered problems in reducing levels of AOX in the presence of halogenated hydrocarbons. Serious problems in process control may arise when ozone is conventionally added and forms bubbles in the presence of surface-active substances; this foam accumulates and is so persistent as to evade mechanical control. Since the formation of foam is directly due to gas bubbles carried in, bubble-free addition of ozone through a membrane may be a viable approach. (orig.) [German] Voraussetzung fuer den Erfolg einer Nassoxidation ist eine sehr genau eingestellte und sorgfaeltig ueberwachte Prozessfuehrung, da anderenfalls auch eine Verschlechterung der Wasserqualitaet eintreten kann; insbesondere haben sich hier bei frueheren Untersuchungen zur Ozonung von Deponiesickerwaessern Schwierigkeiten bei der Reduzierung des AOX-Wertes in Anwesenheit von halogenierten Kohlenwasserstoffen ergeben. Gravierende Schwierigkeiten in der Prozessfuehrung kann Schaum bereiten, der sich bei konventionellem Blaseneintrag des Ozons in Anwesenheit von oberflaechenaktiven Substanzen bildet, sich in der Anlage ansammelt und dabei so bestaendig ist, dass er auf mechanische Weise nicht zu kontrollieren ist. Da die Schaumbildung direkt auf die eingetragenen Gasblasen zurueckzufuehren ist, stellt der blasenfreie Eintrag von Ozon durch eine Membran einen moeglichen Loesungsansatz dar. (orig.)

  1. Stem wood properties of Populus tremuloides, Betula papyrifera and Acer saccharum saplings after three years of treatments to elevated carbon dioxide and ozone

    Science.gov (United States)

    Seija Kaakinen; Katri Kostiainen; Fredrik Ek; Pekka Saranpaa; Mark E. Kubiske; Jaak Sober; David F. Karnosky; Elina Vapaavuori

    2004-01-01

    The aim of this study was to examine the effects of elevated carbon dioxide [CO2] and ozone [O3] and their interaction on wood chemistry and anatomy of five clones of 3-year-old trembling aspen (Populus tremuloides Michx.). Wood chemistry was studied also on paper birch (Betula papyrifera...

  2. Oxidation by UV and ozone of organic contaminants dissolved in deionized and raw mains water

    International Nuclear Information System (INIS)

    Francis, P.D.

    1987-01-01

    Organic contaminants dissolved in deionized pretreated and raw mains water were reacted with ultraviolet light and ozone. Ozone first was used for partial oxidation followed by ozone combined with ultraviolet radiation to produce total oxidation. The reduction of total organic carbon (TOC) level and direct oxidation of halogenated compounds were measured throughout the treatment process. The rate of TOC reduction was compared for ozone injected upstream and inside the reactor

  3. Ozone as an air pollutant

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    1996-01-01

    A Danish new book on ozone as an air pollutant has been reviewed. The Book is "Ozon som luftforurening" by Jes Fenger, Published by "Danmarks Miljøundersøgelser, 1995.......A Danish new book on ozone as an air pollutant has been reviewed. The Book is "Ozon som luftforurening" by Jes Fenger, Published by "Danmarks Miljøundersøgelser, 1995....

  4. Fe-Mn bi-metallic oxides loaded on granular activated carbon to enhance dye removal by catalytic ozonation.

    Science.gov (United States)

    Tang, Shoufeng; Yuan, Deling; Zhang, Qi; Liu, Yameng; Zhang, Qi; Liu, Zhengquan; Huang, Haiming

    2016-09-01

    A Fe-Mn bi-metallic oxide supported on granular activated carbon (Fe-Mn GAC) has been fabricated by an impregnation-desiccation method and tested in the catalytic ozonation of methyl orange (MO) degradation and mineralization. X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy characterizations revealed that Fe-Mn oxides were successfully loaded and uniformly distributed on the GAC, and nitrogen adsorption isotherms showed that the supported GAC retained a large surface area and a high pore volume compared with the pristine GAC. The catalytic activity was systematically assessed by monitoring the MO removal efficiencies at different operational parameters, such as catalyst dosage, initial solution pH, and ozone flow rate. The Fe-Mn GAC exhibited better catalytic activity relative to ozone alone and GAC alone, improving the TOC removal by 24.5 and 11.5 % and COD removal by 13.6 and 7.3 %, respectively. The reusability of the hybrid was examined over five consecutive cyclic treatments. The Fe-Mn GAC catalytic activity was only a slight loss in the cycles, showing good stability. The addition of Na2CO3 as hydroxyl radicals (•OH) scavengers proved that the catalytic ozonation mechanism was the enhanced generation of •OH by the Fe-Mn GAC. The above results render the Fe-Mn GAC an industrially promising candidate for catalytic ozonation of dye contaminant removal.

  5. Enamel and dentin bond strength following gaseous ozone application.

    Science.gov (United States)

    Cadenaro, Milena; Delise, Chiara; Antoniollo, Francesca; Navarra, Ottavia Chiara; Di Lenarda, Roberto; Breschi, Lorenzo

    2009-08-01

    To evaluate the effects of gaseous ozone application on enamel and dentin bond strength produced by two self-etching adhesive systems. The shear bond strength test was conducted to assess adhesion on enamel (protocol 1), while the microtensile bond strength test was performed on dentin (protocol 2). Protocol 1: 96 bovine incisors were randomly divided into 4 groups, and enamel surfaces were bonded in accordance with the following treatments: (1E) ozone + Clearfil Protect Bond; (2E) Clearfil Protect Bond (control); (3E) ozone + Xeno III; (4E) Xeno III (control). Ozone gas was applied for 80 s. Shear bond strength was measured with a universal testing machine. Protocol 2: 40 noncarious human molars were selected. Middle/deep dentin was exposed and bonded in accordance with the following treatments: (1D) ozone+Clearfil Protect Bond; (2D) Clearfil Protect Bond (control); (3D) ozone+Xeno III (4D) Xeno III (control). Four-mm-thick buildups were built on the adhesives, then specimens were sectioned in accordance with the nontrimming technique. Specimens were stressed until failure occurred, and failure modes were analyzed. Shear bond and microtensile bond strength data were analyzed using two-way ANOVA and Tukey's post-hoc test. No statistical differences were found between ozone treated specimens and controls, neither on enamel nor on dentin irrespective of the tested adhesive. Clearfil Protect Bond showed higher bond strength to enamel than Xeno III, irrespective of the ozone treatment (p enamel and dentin bond strength.

  6. Ozone therapy in the management and prevention of caries

    Directory of Open Access Journals (Sweden)

    Merve Erkmen Almaz

    2015-01-01

    Full Text Available The purpose of this article was to assess the effectiveness of ozone therapy in the management and prevention of caries, reviewing clinical and in vitro studies. Ozone has proven to be effective against gram-negative and gram-positive bacteria, viruses, and fungi. In dentistry, most of the published articles are based on ozone's antimicrobial effects and the treatment of caries. Most of the clinical studies reported ozone to be a promising alternative to conventional methods for caries management. However, a few studies have shown ozone to be insufficient for preventing caries and reducing microorganisms in open occlusal carious lesions. Ozone might be a useful tool to reduce and control oral infectious microorganisms in dental plaque and dental cavity. However, the results of in vitro studies are controversial; while some researchers reported that ozone therapy had a minimal or no effect on the viability of microorganisms, others suggested ozone to be highly effective in killing both gram-positive and gram-negative oral microorganisms. Therefore, more evidence is required before ozone can be accepted as an alternative to present methods for the management and prevention of caries.

  7. Optimized lens-sparing treatment of retinoblastoma with electron beams

    NARCIS (Netherlands)

    Steenbakkers, RJHM; Altschuler, MD; DAngio, GJ; Goldwein, JW; Kassaee, A

    1997-01-01

    Purpose: The ideal lens-sparing radiotherapy technique for retinoblastoma calls for 100% dose to the entire retina including the ora serrata and zero dose to the lens, Published techniques, most of which use photons, have not accomplished this ideal treatment. We describe here a technique that

  8. OZONE ABSORPTION IN RAW WATERS

    Directory of Open Access Journals (Sweden)

    LJILJANA TAKIĆ

    2008-03-01

    Full Text Available The ozone absorption in raw water entering the main ozonization step at the Belgrade drinking water supply plant was investigated in a continuous stirred tank reactor (CSTR. A slow chemical reaction rate of dissolved ozone and pollutants present in raw water have been experimentally determined. The modified Hatta number was defined and calculated as a criterion which determines whether and to which extent the reactions of ozone and pollutants influence the rate of the pure physical ozone absorption.

  9. Ozone, greenhouse effect. Ozone, effet de serre

    Energy Technology Data Exchange (ETDEWEB)

    Aviam, A.M.; Arthaut, R.

    1992-12-01

    This file is made of eight general papers on environment (climates under observation, research on photo-oxidizing pollution, scientific aspects of stratospheric ozone layer, urban engineering and environment, glory of public gardens, earths not very natural, darwinism and society, economical data on environment). (A.B.). refs., 3 tabs.

  10. Japan’s experience of flue gas treatment by electron beams

    International Nuclear Information System (INIS)

    Machi, S.

    2011-01-01

    The electron beam flue gas treatment technology was invented in Japan in 1970's. The paper presents the outlook of the Japanese activities on the development and present state of EBFGT technology. (author)

  11. Japan’s experience of flue gas treatment by electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Machi, S.

    2011-07-01

    The electron beam flue gas treatment technology was invented in Japan in 1970's. The paper presents the outlook of the Japanese activities on the development and present state of EBFGT technology. (author)

  12. Fractal structure formation on the surfaces of solids subjected to high intensity electron and ion treatment

    International Nuclear Information System (INIS)

    Altajskij, M.V.; Ivanov, V.V.; Korenev, S.A.; Orelovich, O.L.; Puzynin, I.V.; Chernik, V.V.

    1997-01-01

    We discuss the results of scanning electron microscopy of surfaces of the solids subjected to high intensity electron and ion beam treatment. The appearance of fractal structures on the modified surfaces is shown. The fractal dimensions of these structures were estimated by box-counting algorithm

  13. Automatic programmable air ozonizer

    International Nuclear Information System (INIS)

    Gubarev, S.P.; Klosovsky, A.V.; Opaleva, G.P.; Taran, V.S.; Zolototrubova, M.I.

    2015-01-01

    In this paper we describe a compact, economical, easy to manage auto air ozonator developed at the Institute of Plasma Physics of the NSC KIPT. It is designed for sanitation, disinfection of premises and cleaning the air from foreign odors. A distinctive feature of the developed device is the generation of a given concentration of ozone, approximately 0.7 maximum allowable concentration (MAC), and automatic maintenance of a specified level. This allows people to be inside the processed premises during operation. The microprocessor controller to control the operation of the ozonator was developed

  14. [Curative effect of ozone hydrotherapy for pemphigus].

    Science.gov (United States)

    Jiang, Fuqiong; Deng, Danqi; Li, Xiaolan; Wang, Wenfang; Xie, Hong; Wu, Yongzhuo; Luan, Chunyan; Yang, Binbin

    2018-02-28

    To determine clinical curative effects of ozone therapy for pemphigus vulgaris.
 Methods: Ozone hydrotherapy was used as an aid treatment for 32 patients with pemphigus vulgaris. The hydropathic compression of potassium permanganate solution for 34 patients with pemphigus vulgaris served as a control. The main treatment for both groups were glucocorticoids and immune inhibitors. The lesions of patients, bacterial infection, usage of antibiotics, patient's satisfaction, and clinical curative effect were evaluated in the 2 groups.
 Results: There was no significant difference in the curative effect and the average length of staying at hospital between the 2 groups (P>0.05). But rate for the usage of antibiotics was significantly reduced in the group of ozone hydrotherapy (P=0.039). The patients were more satisfied in using ozone hydrotherapy than the potassium permanganate solution after 7-day therapy (P>0.05).
 Conclusion: Ozone hydrotherapy is a safe and effective aid method for pemphigus vulgaris. It can reduce the usage of antibiotics.

  15. The electron beam treatment process for site remediation

    International Nuclear Information System (INIS)

    Cooper, W.J.; Nickelsen, M.G.; Waite, T.D.; Kurucz, C.N.

    1994-01-01

    This paper summarizes recent studies in the application of high energy electrons for the destruction of toxic organic compounds in hazardous waste leachates. Initial studies have been conducted using single organic solutes in treated groundwater. The solutes of interest are among those most frequently reported in hazardous waste leachates or contaminated ground water. From these studies it has been shown that the process can effectively remove a number of different regulated organic compounds. Using a kinetically based model for open-quotes pure-waterclose quotes the authors have undertaken studies to extend this model to account for the destruction of these compounds in natural waters. Because of the presence of numerous radical scavengers in natural water, e.g., carbonate/biocarbonate ion, dissolved organic carbon, and oxygen, this requires adding a substantial number of bimolecular reaction rate constants. However, it appears that even though many of the reaction rate constants are not known reasonable predictions are possible

  16. Comparative study of ozonized olive oil and ozonized sunflower oil

    Directory of Open Access Journals (Sweden)

    Díaz Maritza F.

    2006-01-01

    Full Text Available In this study the ozonized olive and sunflower oils are chemical and microbiologically compared. These oils were introduced into a reactor with bubbling ozone gas in a water bath at room temperature until they were solidified. The peroxide, acidity and iodine values along with antimicrobial activity were determined. Ozonization effects on the fatty acid composition of these oils were analyzed using Gas-Liquid Chromatographic Technique. An increase in peroxidation and acidity values was observed in both oils but they were higher in ozonized sunflower oil. Iodine value was zero in ozonized olive oil whereas in ozonized sunflower was 8.8 g Iodine per 100 g. The antimicrobial activity was similar for both ozonized oils except for Minimum Bactericidal Concentrations of Pseudomona aeruginosa. Composition of fatty acids in both ozonized oils showed gradual decrease in unsaturated fatty acids (C18:1, C18:2 with gradual increase in ozone doses.

  17. Prediction of required ozone dosage for pilot recirculating aquaculture systems based on laboratory studies

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Rojas-Tirado, Paula Andrea; Kaarsholm, Kamilla Marie Speht

    2017-01-01

    In recirculating aquaculture systems (RAS), the water quality changes continuously. Organic and inorganic compounds accumulates creating toxic conditions for the farmed organisms. Ozone improves water quality diminishing significantly both bacteria load and dissolved organic matter. However......, in a non-meticulously designed system, residual ozone might reach the culture tanks causing significant harm to cultured species or excess costs. The aim of the study was to predict the suitable ozone dosage in pilot RAS, for water treatment purposes, based on laboratory studies. The ozone effect on water...... quality of freshwater RAS and system’s ozone demand was investigated. Bench-scale ozonation experiments revealed the ozone demand of the system to be 180 mg O3/h. Three different ozone dosages were applied to four replicated systems with fixed feed loading (1.56 kg feed/m3 make up water). Results...

  18. SU-E-T-210: Comparison of Proton with Electron Boost in Breast Cancer Treatment

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Y; Chang, A [Procure Proton Therapy Center, Oklahoma City, OK (United States); Liu, Y [INTEGRIS Cancer Institute of Oklahoma, Oklahoma City, OK (United States)

    2015-06-15

    Purpose: Electron beams are commonly used for boost radiation following whole breast irradiation (WBI) to improve the in-breast local control. Proton beams have a finite range and a sharper distal dose falloff compared to electron beams, thus potentially sparing more heart and lung in breast treatment. The purpose of the study is to compare protons with electrons for boost breast treatment in terms of target coverage and normal tissue sparing. Methods: Six breast cancer patients were included in this study. All women received WBI to 45–50 Gy, followed by a 10–16.2 Gy boost with standard fractionation. If proton beams were used for the boost treatment, an electron plan was retrospectively generated for comparison using the same CT set and structures, and vice versa if electron beams were used for treatment. Proton plans were generated using the treatment planning system (TPS) with two to three uniform scanning proton beams. Electron plans were generated using the Pinnacle TPS with one single en face beam. Dose-volume histograms (DVH) were calculated and compared between proton and electron boost plans. Results: Proton plans show a similar boost target coverage, similar skin dose, and much better heart and lung sparing. For an example patient, V95% for PTV was 99.98% and skin (5 mm shell) received a max dose close to the prescription dose for both protons and electrons; however, V2 and V5 for the ipsilateral lung and heart were 37.5%, 17.9% and 19.9%, 4.9% respectively for electrons, but were essentially 0 for protons. Conclusions: This dosimetric comparison demonstrates that while both proton therapy and electron therapy provided similar coverage and skin dose, proton therapy could largely reduce the dose to lung and heart, thus leading to potential less side effects.

  19. Effect of ozonation on microbial fish pathogens, ammonia, nitrate, nitrite, and bod in simulated reuse hatchery water

    Energy Technology Data Exchange (ETDEWEB)

    Colberg, P.J.; Lingg, A.J.

    1978-10-01

    The effectiveness of ozone for eliminating fish pathogens and reducing nitrite, ammonia, and BOD associated with reuse hatchery systems was evaluated. Comparative survival rates of four bacterial fish pathogens and a bacterium-protozoan population during batch and continuous flow ozonation indicated a specific microbial ozone demand during batch treatment and 99% mortality of pathogens during continuous flow treatment. Oxidation of carbon and nitrite by ozone was rapid at low ozone concentrations; carbon and ammonia oxidation rates were pH dependent. The oxidation capacity of ozone in water was greatest at elevated pH even though lower ozone concentrations were used. Ozone treatment appears to be successful for disinfecting hatchery makeup water for recycling. However, the economics of such treatment are yet to be determined. (10 graphs, 28 references, 1 table)

  20. Electron beam treatment with radical scavengers/enhancers

    International Nuclear Information System (INIS)

    Gehringer, P.

    1994-08-01

    E-beam treatment of low level contaminated groundwater is best apt to demonstrate the role of scavengers and enhancers, respectively because groundwater already contains some scavengers as natural solutes. The action of ionizing radiation to water is known to result in the formation of ions, molecular and free radical species. For low level contaminations of groundwater (pollutant concentration aqu - and H are of interest for pollutant decomposition. The pollutants have to compete for the free radical species with the natural solutes. 10 figures are discussed. (author)

  1. Addressing Ozone Layer Depletion

    Science.gov (United States)

    Access information on EPA's efforts to address ozone layer depletion through regulations, collaborations with stakeholders, international treaties, partnerships with the private sector, and enforcement actions under Title VI of the Clean Air Act.

  2. Ozone health effects

    International Nuclear Information System (INIS)

    Easterly, C.

    1994-01-01

    Ozone is a principal component of photochemical air pollution endogenous to numerous metropolitan areas. It is primarily formed by the oxidation of NOx in the presence of sunlight and reactive organic compounds. Ozone is a highly active oxidizing agent capable of causing injury to the lung. Lung injury may take the form of irritant effects on the respiratory tract that impair pulmonary function and result in subjective symptoms of respiratory discomfort. These symptoms include, but are not limited to, cough and shortness of breath, and they can limit exercise performance. The effects of ozone observed in humans have been primarily limited to alterations in respiratory function, and a range of respiratory physiological parameters have been measured as a function of ozone exposure in adults and children. These affects have been observed under widely varying (clinical experimental and environmental settings) conditions

  3. 2001 Ozone Design Value

    Data.gov (United States)

    U.S. Environmental Protection Agency — Ozone is generated by a complex atmoshperic chemical process. Industrial and automobile pollutants in the form of oxides of nitrogen and hydrocarbons react in the...

  4. Thermoluminescence as a tool for monitoring ozone-stressed plants

    Energy Technology Data Exchange (ETDEWEB)

    Skotnica, J.; Gilbert, M.; Weingart, I.; Wilhelm, C

    2003-05-01

    Thermoluminescence parameters are more sensitive to ozone than fluorescence parameters (F{sub 0}, F{sub M}, F{sub v}/F{sub M}). - The effect of ozone (6 h, various concentrations from 0 to 350 ppb) on barley (Hordeum vulgare L., cv. Bomi) and tomato (Lycopersicon esculentum L., cv. Yellow Cherry) leaves was investigated in parallel by thermoluminescence (TL) and fluorescence (FL) methods. Several significant changes were found in TL glow curves measured after excitation by one single turnover flash at +2 deg. C in the temperature range from 2 to 170 deg. C immediately after ozone exposure. Contrary to TL, ozone induced only negligible changes in FL parameters F{sub 0}, F{sub M} and F{sub v}/F{sub M}. Measurements done 24 h after ozone exposure showed partial recovery of ozone-induced changes. The extent of recovery was not the same in different parts of TL curves. Fluorescence parameters were not significantly changed. The results demonstrate that TL parameters are more sensitive to ozone than conventially used FL parameters F{sub 0}, F{sub M} and F{sub v}/F{sub M}. Moreover, TL measurements seem to give information not only about the PSII electron transport, but also about the extent of oxidative damage and membrane lipid peroxidation. It is concluded, that TL can be a highly informative tool for monitoring the impact of ozone on plants.

  5. Electron beams for power plant flue gas treatment

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    1998-01-01

    Among the processes in which fuel is used for energy generation coal burning plays leading role. On the other hand combustion of fossil fuels is the biggest source of air pollution. When burning fossil fuel pollutants such as particulate, sulfur oxides, nitrogen oxides, volatile organic compounds and others are emitted. Air pollution caused by these pollutants not only acts directly on environment but by contamination of water and soil leads to their degradation. The advanced technology for simultaneous SO 2 , NO x and VOC removal is discussed in the paper. The technology is based on electron accelerators applications. Many new solutions have been introduced in the new pilot plants which have been operated at coal fired power stations. 98% SO 2 and up to 90% NO x removals were obtained at very moderate energy consumption (for de SO x ). Additional agricultural tests have proven full applicability of byproduct in pure form or as a blending stock for NPK fertilizers. Two full scale industrial plants are being built in China (640 kW accelerators) and Poland (1.2 MW accelerators). These will be the biggest radiation processing units using accelerator technology all over the world

  6. Electron beam treatment parameters for control of stored product insects

    International Nuclear Information System (INIS)

    Cleghorn, D.A.; Nablo, S.V.; Ferro, D.N.; Hagstrum, D.W.

    2002-01-01

    The fluidized bed process (EBFB) has been evaluated for the disinfestation of cereal grains. The various life stages from egg to adult have been studied on the 225 kV pilot as a function of surface dose. Three of the most common pests were selected: the rice weevil (S. oryzae), the lesser grain borer (R. dominica) and the red flour beetle (T. castaneum). The major challenge to this process lies in those 'protected' life-stages active deeply within the endosperm of the grain kernel. The rice weevil is such an internal feeder in which the larvae develop through several molts during several weeks before pupation and adult emergence. Product velocities up to 2000 m/min have been used for infested hard winter wheat at dose levels up to 1000 Gy. Detailed depth of penetration studies at three life stages of S. oryzae larvae were conducted at 225-700 kV and demonstrated effective mortality at 400 kVx200 Gy. Mortality data are also presented for the radiation labile eggs of these insects as well as the (sterile) adults, which typically lived for several weeks before death. These results are compared with earlier 60 Co gamma-ray studies on these same insects. Based upon these studies, the effectiveness of the fluidized bed process employing self-shielded electron beam equipment for insect control in wheat/rice at sub-kilogray dose levels has been demonstrated

  7. Plasmachemical and heterogeneous processes in ozonizers with oxygen activation by a dielectric barrier discharge

    Energy Technology Data Exchange (ETDEWEB)

    Mankelevich, Yu. A., E-mail: ymankelevich@mics.msu.su; Voronina, E. N.; Poroykov, A. Yu.; Rakhimov, T. V.; Voloshin, D. G.; Chukalovsky, A. A. [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation)

    2016-10-15

    Plasmachemical and heterogeneous processes of generation and loss of ozone in the atmosphericpressure dielectric barrier discharge in oxygen are studied theoretically. Plasmachemical and electronic kinetics in the stage of development and decay of a single plasma filament (microdischarge) are calculated numerically with and without allowance for the effects of ozone vibrational excitation and high initial ozone concentration. The developed analytical approach is applied to determine the output ozone concentration taking into account ozone heterogeneous losses on the Al{sub 2}O{sub 3} dielectric surface. Using the results of quantummechanical calculations by the method of density functional theory, a multistage catalytic mechanism of heterogeneous ozone loss based on the initial passivation of a pure Al{sub 2}O{sub 3} surface by ozone and the subsequent interaction of O{sub 3} molecules with the passivated surface is proposed. It is shown that the conversion reaction 2O{sub 3} → 3O{sub 2} of a gas-phase ozone molecule with a physically adsorbed ozone molecule can result in the saturation of the maximum achievable ozone concentration at high specific energy depositions, the nonstationarity of the output ozone concentration, and its dependence on the prehistory of ozonizer operation.

  8. Investigation of a combined platinum and electron lifetime control treatment for silicon

    International Nuclear Information System (INIS)

    Jia, Yunpeng; Cui, Zhihang; Yang, Fei; Zhao, Bao; Zou, Shikai; Liang, Yongsheng

    2017-01-01

    In silicon, the effect of Combined Lifetime Treatment (CLT) involving platinum diffusion and subsequent electron irradiation is different from the separate treatments of platinum diffusion and electron irradiation, even the treatment of electron irradiation followed by platinum diffusion. In this paper, we investigated the experimental behavior of different kinds of lifetime treated samples. We found that the reverse leakage current (I rr ) increases with the increasing platinum diffusion temperature or electron irradiation dose in the separate treatments. Conversely, I rr of the CLT samples decreased with rising platinum diffusion temperature at the same dose of subsequent electron irradiation. By deep-level transient spectroscopy (DLTS), a new energy level E7 (Ec −0.376 eV) was found in our CLT samples. The new level E7 suppresses the dominance of the deeper level E8 (Ec −0.476 eV), which is caused by electron irradiation directly and results in I rr ’s increase. The formation of the level E7 comes from the complex defect-combined effect between platinum atoms and silicon vacancies, and it affects device’s characteristics finally. These research will be helpful to the development of platinum-diffused devices used in intense electron irradiation environments.

  9. Investigation of a combined platinum and electron lifetime control treatment for silicon

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Yunpeng [College of Electronic Information and Control Engineering, Beijing University of Technology, Beijing 100124 (China); Cui, Zhihang, E-mail: czhczh321321@126.com [College of Electronic Information and Control Engineering, Beijing University of Technology, Beijing 100124 (China); Yang, Fei [State Grid Smart Electrical Engineering, Beijing 100192 (China); Zhao, Bao; Zou, Shikai; Liang, Yongsheng [College of Electronic Information and Control Engineering, Beijing University of Technology, Beijing 100124 (China)

    2017-02-01

    In silicon, the effect of Combined Lifetime Treatment (CLT) involving platinum diffusion and subsequent electron irradiation is different from the separate treatments of platinum diffusion and electron irradiation, even the treatment of electron irradiation followed by platinum diffusion. In this paper, we investigated the experimental behavior of different kinds of lifetime treated samples. We found that the reverse leakage current (I{sub rr}) increases with the increasing platinum diffusion temperature or electron irradiation dose in the separate treatments. Conversely, I{sub rr} of the CLT samples decreased with rising platinum diffusion temperature at the same dose of subsequent electron irradiation. By deep-level transient spectroscopy (DLTS), a new energy level E7 (Ec −0.376 eV) was found in our CLT samples. The new level E7 suppresses the dominance of the deeper level E8 (Ec −0.476 eV), which is caused by electron irradiation directly and results in I{sub rr}’s increase. The formation of the level E7 comes from the complex defect-combined effect between platinum atoms and silicon vacancies, and it affects device’s characteristics finally. These research will be helpful to the development of platinum-diffused devices used in intense electron irradiation environments.

  10. Monte Carlo based electron treatment planning and cutout output factor calculations

    Science.gov (United States)

    Mitrou, Ellis

    Electron radiotherapy (RT) offers a number of advantages over photons. The high surface dose, combined with a rapid dose fall-off beyond the target volume presents a net increase in tumor control probability and decreases the normal tissue complication for superficial tumors. Electron treatments are normally delivered clinically without previously calculated dose distributions due to the complexity of the electron transport involved and greater error in planning accuracy. This research uses Monte Carlo (MC) methods to model clinical electron beams in order to accurately calculate electron beam dose distributions in patients as well as calculate cutout output factors, reducing the need for a clinical measurement. The present work is incorporated into a research MC calculation system: McGill Monte Carlo Treatment Planning (MMCTP) system. Measurements of PDDs, profiles and output factors in addition to 2D GAFCHROMICRTM EBT2 film measurements in heterogeneous phantoms were obtained to commission the electron beam model. The use of MC for electron TP will provide more accurate treatments and yield greater knowledge of the electron dose distribution within the patient. The calculation of output factors could invoke a clinical time saving of up to 1 hour per patient.

  11. Research and development on municipal Wastewater treatment processes using electron beams

    International Nuclear Information System (INIS)

    Kashiwaya, Mamoru

    1994-01-01

    This paper was described concerning the experimental results and their engineering evaluations on electron beam irradiation treatment to effluent and sludge produced in existing municipal wastewater treatment plants implemented by the Japan Atomic Energy Research Institute and the study committee for past five years. Laboratory tests using an electron accelerator were carried out for the purposes of disinfection both to effluent and to dewatered sludge. And composting tests by a pilot-plant were also carried out to find the optimal conditions on design and operation, and initial and operational cost estimations for pelletized sludge with/without the irradiation. It was found that these applications to effluent, sludge and supernatant were quite effective. However, several problems awaiting solution were found from the tests and evaluating works on the matters of marketed electron accelerators. As the results of tests and evaluating works, electron beam irradiation treatment process applied to effluent should be carried out at the municipal wastewater treatment plants. Regenerated granular activated carbon treated by electron beam irradiation may also be applicable to remove hazardous organic substances in effluent. However, long-term tests by pilotplants will be necessary to determine the design criteria, operation and maintenance conditions, and so on. For composting of dewatered sludge produced at municipal wastewater treatment plants, several sizes of smaller electron accelerator are required to be on the market. Especially, medium and small sizes municipalities expect to install composting facilities in the plant. (J.P.N.)

  12. The ozone backlash

    International Nuclear Information System (INIS)

    Taubes, G.

    1993-01-01

    While evidence for the role of chlorofluorocarbons in ozone depletion grows stronger, researchers have recently been subjected to vocal public criticism of their theories-and their motives. Their understanding of the mechanisms of ozone destruction-especially the annual ozone hole that appears in the Antarctic-has grown stronger, yet everywhere they go these days, they seem to be confronted by critics attacking their theories as baseless. For instance, Rush Limbaugh, the conservative political talk-show host and now-best-selling author of The Way Things Ought to Be, regularly insists that the theory of ozone depletion by CFCs is a hoax: bladerdash and poppycock. Zoologist Dixy Lee Ray, former governor of the state of Washington and former head of the Atomic Energy Commission, makes the same argument in her book, Trashing the Planet. The Wall Street Journal and National Review have run commentaries by S. Fred Singer, a former chief scientists for the Department of Transportation, purporting to shoot holes in the theory of ozone depletion. Even the June issue of Omni, a magazine with a circulation of more than 1 million that publishes a mixture of science and science fiction, printed a feature article claiming to expose ozone research as a politically motivated scam

  13. Ozone depletion calculations

    International Nuclear Information System (INIS)

    Luther, F.M.; Chang, J.S.; Wuebbles, D.J.; Penner, J.E.

    1992-01-01

    Models of stratospheric chemistry have been primarily directed toward an understanding of the behavior of stratospheric ozone. Initially this interest reflected the diagnostic role of ozone in the understanding of atmospheric transport processes. More recently, interest in stratospheric ozone has arisen from concern that human activities might affect the amount of stratospheric ozone, thereby affecting the ultraviolet radiation reaching the earth's surface and perhaps also affecting the climate with various potentially severe consequences for human welfare. This concern has inspired a substantial effort to develop both diagnostic and prognostic models of stratospheric ozone. During the past decade, several chemical agents have been determined to have potentially significant impacts on stratospheric ozone if they are released to the atmosphere in large quantities. These include oxides of nitrogen, oxides of hydrogen, chlorofluorocarbons, bromine compounds, fluorine compounds and carbon dioxide. In order to assess the potential impact of the perturbations caused by these chemicals, mathematical models have been developed to handle the complex coupling between chemical, radiative, and dynamical processes. Basic concepts in stratospheric modeling are reviewed

  14. Ozone sonde cell current measurements and implications for observations of near-zero ozone concentrations in the tropical upper troposphere

    Directory of Open Access Journals (Sweden)

    H. Vömel

    2010-04-01

    Full Text Available Laboratory measurements of the Electrochemical Concentration Cell (ECC ozone sonde cell current using ozone free air as well as defined amounts of ozone reveal that background current measurements during sonde preparation are neither constant as a function of time, nor constant as a function of ozone concentration. Using a background current, measured at a defined timed after exposure to high ozone may often overestimate the real background, leading to artificially low ozone concentrations in the upper tropical troposphere, and may frequently lead to operator dependent uncertainties. Based on these laboratory measurements an improved cell current to partial pressure conversion is proposed, which removes operator dependent variability in the background reading and possible artifacts in this measurement. Data from the Central Equatorial Pacific Experiment (CEPEX have been reprocessed using the improved background treatment based on these laboratory measurements. In the reprocessed data set near-zero ozone events no longer occur. At Samoa, Fiji, Tahiti, and San Cristóbal, nearly all near-zero ozone concentrations occur in soundings with larger background currents. To a large extent, these events are no longer observed in the reprocessed data set using the improved background treatment.

  15. Natural zeolite reactivity towards ozone: The role of compensating cations

    International Nuclear Information System (INIS)

    Valdés, Héctor; Alejandro, Serguei; Zaror, Claudio A.

    2012-01-01

    Highlights: ► Chemical and thermal treatment enhances catalytic activity of natural zeolite. ► Modified natural zeolite exhibits high stability after thermal treatment. ► Reducing the compensating cation content leads to an increase on ozone abatement. ► Surface active atomic oxygen was detected using the DRIFT technique. ► The highest reactivity toward ozone was performed by NH4Z3 zeolite sample. - Abstract: Among indoor pollutants, ozone is recognised to pose a threat to human health. Recently, low cost natural zeolites have been applied as alternative materials for ozone abatement. In this work, the effect of compensating cation content of natural zeolite on ozone removal is studied. A Chilean natural zeolite is used here as starting material. The amount of compensating cations in the zeolite framework was modified by ion exchange using an ammonium sulphate solution (0.1 mol L −1 ). Characterisation of natural and modified zeolites were performed by X-ray powder diffraction (XRD), nitrogen adsorption at 77 K, elemental analysis, X-ray fluorescence (XRF), thermogravimetric analysis coupled with mass spectroscopy (TGA-MS), and temperature-programmed desorption of ammonia (NH 3 -TPD). Ozone adsorption and/or decomposition on natural and modified zeolites were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Results show that the zeolite compensating cation content affects ozone interaction with zeolite active sites. Ammonium ion-exchange treatments followed by thermal out-gassing at 823 K, reduces ozone diffusion resistance inside the zeolite framework, increasing ozone abatement on zeolite surface active sites. Weak and strong Lewis acid sites of zeolite surface are identified here as the main active sites responsible of ozone removal.

  16. Natural zeolite reactivity towards ozone: The role of compensating cations

    Energy Technology Data Exchange (ETDEWEB)

    Valdes, Hector, E-mail: hvaldes@ucsc.cl [Laboratorio de Tecnologias Limpias (F. Ingenieria), Universidad Catolica de la Santisima Concepcion, Alonso de Ribera 2850, Concepcion (Chile); Alejandro, Serguei; Zaror, Claudio A. [Departamento de Ingenieria Quimica (F. Ingenieria), Universidad de Concepcion, Concepcion (Chile)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer Chemical and thermal treatment enhances catalytic activity of natural zeolite. Black-Right-Pointing-Pointer Modified natural zeolite exhibits high stability after thermal treatment. Black-Right-Pointing-Pointer Reducing the compensating cation content leads to an increase on ozone abatement. Black-Right-Pointing-Pointer Surface active atomic oxygen was detected using the DRIFT technique. Black-Right-Pointing-Pointer The highest reactivity toward ozone was performed by NH4Z3 zeolite sample. - Abstract: Among indoor pollutants, ozone is recognised to pose a threat to human health. Recently, low cost natural zeolites have been applied as alternative materials for ozone abatement. In this work, the effect of compensating cation content of natural zeolite on ozone removal is studied. A Chilean natural zeolite is used here as starting material. The amount of compensating cations in the zeolite framework was modified by ion exchange using an ammonium sulphate solution (0.1 mol L{sup -1}). Characterisation of natural and modified zeolites were performed by X-ray powder diffraction (XRD), nitrogen adsorption at 77 K, elemental analysis, X-ray fluorescence (XRF), thermogravimetric analysis coupled with mass spectroscopy (TGA-MS), and temperature-programmed desorption of ammonia (NH{sub 3}-TPD). Ozone adsorption and/or decomposition on natural and modified zeolites were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Results show that the zeolite compensating cation content affects ozone interaction with zeolite active sites. Ammonium ion-exchange treatments followed by thermal out-gassing at 823 K, reduces ozone diffusion resistance inside the zeolite framework, increasing ozone abatement on zeolite surface active sites. Weak and strong Lewis acid sites of zeolite surface are identified here as the main active sites responsible of ozone removal.

  17. Cooling tower water ozonation at Southern University

    International Nuclear Information System (INIS)

    Chen, C.C.; Knecht, A.T.; Trahan, D.B.; Yaghi, H.M.; Jackson, G.H.; Coppenger, G.D.

    1990-01-01

    Cooling-tower water is a critical utility for many industries. In the past, inexpensive water coupled with moderate regulation of discharge water led to the neglect of the cooling tower as an energy resource. Now, with the increased cost of chemical treatment and tough EPA rules and regulations, this situation is rapidly changing. The operator of the DOE Y-12 Plant in Oak Ridge as well as many other industries are forced to develop an alternate method of water treatment. The cooling tower is one of the major elements in large energy systems. The savings accrued from a well engineered cooling tower can be a significant part of the overall energy conservation plan. During a short-term ozonation study between 1987-1988, the Y-12 Plant has been successful in eliminating the need for cooling tower treatment chemicals. However, the long-term impact was not available. Since April 1988, the ozone cooling water treatment study at the Y-12 Plant has been moved to the site at Southern University in Baton Rouge, Louisiana. The purpose of this continued study is to determine whether the use of ozonation on cooling towers is practical from an economic, technical and environmental standpoint. This paper discusses system design, operating parameter and performance testing of the ozonation system at Southern University

  18. Electrical discharges of plasma ozonizer and its application

    Directory of Open Access Journals (Sweden)

    Tirawanichakul, S.

    2007-05-01

    Full Text Available Ozone synthesis is one of the applications of near atmospheric plasma processing. An ozone generator in this research comprised two annular cylindrical-shaped electrodes. The inner electrode was made ofstainless steel covered with the dielectric glass and the outer electrode was also made of stainless steel. The electric spacing gap was 0.0075 m and length of ozonizer was 0.21 m. Oxygen gas passing through thedischarge gap between two electrodes supplied by an alternating current (AC high voltage power supply, frequency 50 Hz, ranging of 6-10 kVAC was used for producing ozone. The amount of ozone was determinedby the KI standard method. The result showed that the concentration of ozone is proportional to the AC applied voltage. For determining effect of purified oxygen feed rate of 6-10 L/min on quantity of ozone, theresults indicated that at the volumetric flow rate of 8 L/min produced the largest amount of ozone. In addition, ozone concentration at a flow rate of 8 L/min and an electrical discharge time of 3 minutes wasapproximately determined as 41, 60, 80 and 135 mg/L at 8, 9, 10 and 11 kVAC, respectively. Moreover, study of dye wastewater of Krajud mat was proposed and treated by three different methods. Firstly, dye wastewater was solely treated by a plasma ozonation. Secondly, a combination ofozonation and alum coagulation was used for dye wastewater treatment. Finally, the combined ozonation and activated carbon adsorption were used for dye wastewater treatment. The experimental results showedthat the percentage of light absorbance reduction of pink dyed wastewater for these three different methods was about 56%, 35% and 10%, respectively compared to the reference sample. In addition, For thesemethods, the percentage of BOD of treated dye wastewater could be reduced to 64%, 54% and 46% respectively, the percentage of COD could be reduced to approximately 78%, 62% and 27%, respectively, comparedto the reference sample. In conclusion, the

  19. Ozone: The secret greenhouse gas

    International Nuclear Information System (INIS)

    Berntsen, Terje; Tjernshaugen, Andreas

    2001-01-01

    The atmospheric ozone not only protects against harmful ultraviolet radiation; it also contributes to the greenhouse effect. Ozone is one of the jokers to make it difficult to calculate the climatic effect of anthropogenic emissions. The greenhouse effect and the ozone layer should not be confused. The greenhouse effect creates problems when it becomes enhanced, so that the earth becomes warmer. The problem with the ozone layer, on the contrary, is that it becomes thinner and so more of the harmful ultraviolet radiation gets through to the earth. However, ozone is also a greenhouse gas and so the greenhouse effect and the ozone layer are connected

  20. Application of electron beam to industrial wastewater treatment

    International Nuclear Information System (INIS)

    Han, B.; Kim, D.K.; Boo, J.Y.; Kim, J.K.; Kim, Y.; Chung, W.; Choi, J.S.; Kang, H.J.; Pikaev, A.K.

    2001-01-01

    Global withdrawals of water to satisfy human demands have grown dramatically in this century. Between 1900 and 1995, water consumption increased by over six times, more than double the rate of population growth. This rapid growth in water demand is due to the increasing reliance on irrigation to achieve food security, the growth of industrial uses, and the increasing use per capita for domestic purposes. Given the seriousness of the situation and future risk of crises, there is an urgent need to develop the water efficient technologies including economical treatment methods of wastewater and polluted water. In the Central Research Institute of Samsung Heavy Industries (SHI), many industrial wastewater including leachate from landfill area, wastewater from papermill, dyeing complex, petrochemical processes, etc. are under investigation with EB irradiation. For the study of treating dyeing wastewater combined with conventional facilities, an EB pilot plant for treating 1,000m 3 /day of wastewater from 60,000m 3 /day of total dyeing wastewater has been constructed and operated in Taegu Dyeing Industrial Complex. A commercial plant for re-circulation of wastewater from Papermill Company is also designed for S-paper Co. in Cheongwon City, and after the successful installation, up to 80% of wastewater could be re-used in paper producing process. (author)

  1. Feature of flue gas treatment by electron-beam irradiation and details of its development

    International Nuclear Information System (INIS)

    Tokunaga, Okihiro; Suzuki, Nobutake.

    1986-01-01

    The method of flue gas treatment with an electron beam, developed jointly by Japan Atomic Energy Research Institute and Ebara Corporation, is promising as a simple, dry process, not using a catalyst, of the desulfurization and denitration. In the procedure, flue gas is irradiated with an electron beam in the presence of ammonia, so that sulfurous acid gas and nitrogen oxide are converted to ammonium sulfate and ammonium nitrate particles, which are then removed. The method is already demonstrated in the flue gas treatment of an iron ore sintering furnace as pilot test. And further, the pilot tests in coal combustion flue gas treatment are proceeding in the United States and West Germany. For the flue gas treatment method using an electron beam, the mechanisms of desulfurization and denitration, the course taken in its development and the present state of development are described, and also the future outlook and problems. (Mori, K.)

  2. Application of Resonant Converter in Ozone Generator Model

    Directory of Open Access Journals (Sweden)

    Mochammad Facta

    2008-04-01

    Full Text Available Ozone is one of the favorable oxidant to use in home appliance and industry as disinfectant for food processing, food storage, odor abatement, groundwater remediation, and drinking water purification. The common and previous technical method for generating ozone uses a high voltage and low frequency. This kind of method has disadvantage of energy efficiency, size and weight. This paper proposed the use power electronics in the inverter resonant circuit to produce alternating current with high frequency. The basic RLC resonance circuit is used for early study to determine resonance frequency for inverter. As the result, the ozone chamber terminal voltage had been achieved for initiation by using resonance frequency.

  3. Efficacy and fumigation characteristics of ozone in stored maize.

    Science.gov (United States)

    Kells, S A.; Mason, L J.; Maier, D E.; Woloshuk, C P.

    2001-10-01

    This study evaluated the efficacy of ozone as a fumigant to disinfest stored maize. Treatment of 8.9tonnes (350bu) of maize with 50ppm ozone for 3d resulted in 92-100% mortality of adult red flour beetle, Tribolium castaneum (Herbst), adult maize weevil, Sitophilus zeamais (Motsch.), and larval Indian meal moth, Plodia interpunctella (Hübner) and reduced by 63% the contamination level of the fungus Aspergillus parasiticus Speare on the kernel surface. Ozone fumigation of maize had two distinct phases. Phase 1 was characterized by rapid degradation of the ozone and slow movement through the grain. In Phase 2, the ozone flowed freely through the grain with little degradation and occurred once the molecular sites responsible for ozone degradation became saturated. The rate of saturation depended on the velocity of the ozone/air stream. The optimum apparent velocity for deep penetration of ozone into the grain mass was 0.03m/s, a velocity that is achievable in typical storage structures with current fans and motors. At this velocity 85% of the ozone penetrated 2.7m into the column of grain in 0.8d during Phase 1 and within 5d a stable degradation rate of 1ppm/0.3m was achieved. Optimum velocity for Phase 2 was 0.02m/s. At this velocity, 90% of the ozone dose penetrated 2.7m in less than 0.5d. These data demonstrate the potential usefulness of using ozone in managing stored maize and possibly other grains.

  4. Effect of ozone gas processing on physical and chemical properties ...

    African Journals Online (AJOL)

    chemical properties of gluten proteins were investigated after treatment with .... differences in most of the visible bands among all samples. Figure 1: SDS-PAGE analysis of protein patterns in wheat gluten and glutenin, with and without ozone.

  5. Effect of electron-ion treatment on fermentative activity of food yeasts

    International Nuclear Information System (INIS)

    Sergeev, I.N.; Ostapenkov, A.M.

    1988-01-01

    Investigation into effect of electron-ion treatment (EIT) on fermentative activity (FA) of Sacch cerevisial type yeasts of 12 breed was conducted. It is shown that even within the limits of one and the same type different treatment regimes are meded. This is obviously connected with physiologic peculiarities of different yeast breeds. Therefore an individual optimal treatment regime should be determined in each particular case during EIT of different breeds

  6. Theoretical analysis of ozone generation by pulsed dielectric barrier discharge in oxygen

    Science.gov (United States)

    Wei, L. S.; Zhou, J. H.; Wang, Z. H.; Cen, K. F.

    2007-08-01

    The use of very short high-voltage pulses combined with a dielectric layer results in high-energy electrons that dissociate oxygen molecules into atoms, which are a prerequisite for the subsequent production of ozone by collisions with oxygen molecules and third particles. The production of ozone depends on both the electrical and the physical parameters. For ozone generation by pulsed dielectric barrier discharge in oxygen, a mathematical model, which describes the relation between ozone concentration and these parameters that are of importance in its design, is developed according to dimensional analysis theory. A formula considering the ozone destruction factor is derived for predicting the characteristics of the ozone generation, within the range of the corona inception voltage to the gap breakdown voltage. The trend showing the dependence of the concentration of ozone in oxygen on these parameters generally agrees with the experimental results, thus confirming the validity of the mathematical model.

  7. Enhancement of electron field emission of vertically aligned carbon nanotubes by nitrogen plasma treatment

    Energy Technology Data Exchange (ETDEWEB)

    Wang, B.B. [College of Chemistry and Chemical Engineering, Chongqing University of Technology, 69 Hongguang Rd, Lijiatuo, Banan District, Chongqing 400054 (China); Plasma Nanoscience Centre Australia (PNCA), CSIRO Materials Science and Engineering, P.O. Box 218, Lindfield, NSW 2070 (Australia); Cheng, Q.J. [Plasma Nanoscience Centre Australia (PNCA), CSIRO Materials Science and Engineering, P.O. Box 218, Lindfield, NSW 2070 (Australia); Plasma Nanoscience, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Chen, X. [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); Ostrikov, K., E-mail: kostya.ostrikov@csiro.au [Plasma Nanoscience Centre Australia (PNCA), CSIRO Materials Science and Engineering, P.O. Box 218, Lindfield, NSW 2070 (Australia); Plasma Nanoscience, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia)

    2011-09-22

    Highlights: > A new and custom-designed bias-enhanced hot-filament chemical vapor deposition system is developed to synthesize vertically aligned carbon nanotubes. > The carbon nanotubes are later treated with nitrogen plasmas. > The electron field emission characteristics of the carbon nanotubes are significantly improved after the nitrogen plasma treatment. > A new physical mechanism is proposed to interpret the improvement of the field emission characteristics. - Abstract: The electron field emission (EFE) characteristics from vertically aligned carbon nanotubes (VACNTs) without and with treatment by the nitrogen plasma are investigated. The VACNTs with the plasma treatment showed a significant improvement in the EFE property compared to the untreated VACNTs. The morphological, structural, and compositional properties of the VACNTs are extensively examined by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and energy dispersive X-ray spectroscopy. It is shown that the significant EFE improvement of the VACNTs after the nitrogen plasma treatment is closely related to the variation of the morphological and structural properties of the VACNTs. The high current density (299.6 {mu}A/cm{sup 2}) achieved at a low applied field (3.50 V/{mu}m) suggests that the VACNTs after nitrogen plasma treatment can serve as effective electron field emission sources for numerous applications.

  8. Enhancement of electron field emission of vertically aligned carbon nanotubes by nitrogen plasma treatment

    International Nuclear Information System (INIS)

    Wang, B.B.; Cheng, Q.J.; Chen, X.; Ostrikov, K.

    2011-01-01

    Highlights: → A new and custom-designed bias-enhanced hot-filament chemical vapor deposition system is developed to synthesize vertically aligned carbon nanotubes. → The carbon nanotubes are later treated with nitrogen plasmas. → The electron field emission characteristics of the carbon nanotubes are significantly improved after the nitrogen plasma treatment. → A new physical mechanism is proposed to interpret the improvement of the field emission characteristics. - Abstract: The electron field emission (EFE) characteristics from vertically aligned carbon nanotubes (VACNTs) without and with treatment by the nitrogen plasma are investigated. The VACNTs with the plasma treatment showed a significant improvement in the EFE property compared to the untreated VACNTs. The morphological, structural, and compositional properties of the VACNTs are extensively examined by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and energy dispersive X-ray spectroscopy. It is shown that the significant EFE improvement of the VACNTs after the nitrogen plasma treatment is closely related to the variation of the morphological and structural properties of the VACNTs. The high current density (299.6 μA/cm 2 ) achieved at a low applied field (3.50 V/μm) suggests that the VACNTs after nitrogen plasma treatment can serve as effective electron field emission sources for numerous applications.

  9. Ozone modeling within plasmas for ozone sensor applications

    OpenAIRE

    Arshak, Khalil; Forde, Edward; Guiney, Ivor

    2007-01-01

    peer-reviewed Ozone (03) is potentially hazardous to human health and accurate prediction and measurement of this gas is essential in addressing its associated health risks. This paper presents theory to predict the levels of ozone concentration emittedfrom a dielectric barrier discharge (DBD) plasma for ozone sensing applications. This is done by postulating the kinetic model for ozone generation, with a DBD plasma at atmospheric pressure in air, in the form of a set of rate equations....

  10. Simple Technique of Exfoliation and Dispersion of Multilayer Graphene from Natural Graphite by Ozone-Assisted Sonication.

    Science.gov (United States)

    Lin, Zaw; Karthik, Paneer Selvam; Hada, Masaki; Nishikawa, Takeshi; Hayashi, Yasuhiko

    2017-05-27

    Owing to its unique properties, graphene has attracted tremendous attention in many research fields. There is a great space to develop graphene synthesis techniques by an efficient and environmentally friendly approach. In this paper, we report a facile method to synthesize well-dispersed multilayer graphene (MLG) without using any chemical reagents or organic solvents. This was achieved by the ozone-assisted sonication of the natural graphite in a water medium. The frequency or number of ozone treatments plays an important role for the dispersion in the process. The possible mechanism of graphene exfoliation and the introduction of functional groups have been postulated. The experimental setup is unique for ozone treatment and enables the elimination of ozone off-gas. The heat generated by the dissipation of ultrasonic waves was used as it is, and no additional heat was supplied. The graphene dispersion was stable, and no evidence of aggregation was observed---even after several months. The characterization results show that well-dispersed MLG was successfully synthesized without any significant damage to the overall structure. The graphene obtained by this method has potential applications in composite materials, conductive coatings, energy storage, and electronic devices.

  11. Simple Technique of Exfoliation and Dispersion of Multilayer Graphene from Natural Graphite by Ozone-Assisted Sonication

    Directory of Open Access Journals (Sweden)

    Zaw Lin

    2017-05-01

    Full Text Available Owing to its unique properties, graphene has attracted tremendous attention in many research fields. There is a great space to develop graphene synthesis techniques by an efficient and environmentally friendly approach. In this paper, we report a facile method to synthesize well-dispersed multilayer graphene (MLG without using any chemical reagents or organic solvents. This was achieved by the ozone-assisted sonication of the natural graphite in a water medium. The frequency or number of ozone treatments plays an important role for the dispersion in the process. The possible mechanism of graphene exfoliation and the introduction of functional groups have been postulated. The experimental setup is unique for ozone treatment and enables the elimination of ozone off-gas. The heat generated by the dissipation of ultrasonic waves was used as it is, and no additional heat was supplied. The graphene dispersion was stable, and no evidence of aggregation was observed---even after several months. The characterization results show that well-dispersed MLG was successfully synthesized without any significant damage to the overall structure. The graphene obtained by this method has potential applications in composite materials, conductive coatings, energy storage, and electronic devices.

  12. Natural zeolite reactivity towards ozone: the role of compensating cations.

    Science.gov (United States)

    Valdés, Héctor; Alejandro, Serguei; Zaror, Claudio A

    2012-08-15

    Among indoor pollutants, ozone is recognised to pose a threat to human health. Recently, low cost natural zeolites have been applied as alternative materials for ozone abatement. In this work, the effect of compensating cation content of natural zeolite on ozone removal is studied. A Chilean natural zeolite is used here as starting material. The amount of compensating cations in the zeolite framework was modified by ion exchange using an ammonium sulphate solution (0.1 mol L(-1)). Characterisation of natural and modified zeolites were performed by X-ray powder diffraction (XRD), nitrogen adsorption at 77K, elemental analysis, X-ray fluorescence (XRF), thermogravimetric analysis coupled with mass spectroscopy (TGA-MS), and temperature-programmed desorption of ammonia (NH(3)-TPD). Ozone adsorption and/or decomposition on natural and modified zeolites were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Results show that the zeolite compensating cation content affects ozone interaction with zeolite active sites. Ammonium ion-exchange treatments followed by thermal out-gassing at 823 K, reduces ozone diffusion resistance inside the zeolite framework, increasing ozone abatement on zeolite surface active sites. Weak and strong Lewis acid sites of zeolite surface are identified here as the main active sites responsible of ozone removal. Copyright © 2012 Elsevier B.V. All rights reserved.

  13. Application of ozone micro-nano-bubbles to groundwater remediation.

    Science.gov (United States)

    Hu, Liming; Xia, Zhiran

    2018-01-15

    Ozone is widely used for water treatment because of its strong oxidation ability. However, the efficiency of ozone in groundwater remediation is limited because of its relatively low solubility and rapid decomposition in the aqueous phase. Methods for increasing the stability of ozone within the subsurface are drawing increasing attention. Micro-nano-bubbles (MNBs), with diameters ranging from tens of nanometres to tens of micrometres, present rapid mass transfer rates, persist for a relatively long time in water, and transport with groundwater flow, which significantly improve gas concentration and provide a continuous gas supply. Therefore, MNBs show a considerable potential for application in groundwater remediation. In this study, the characteristics of ozone MNBs were examined, including their size distribution, bubble quantity, and zeta potential. The mass transfer rate of ozone MNBs was experimentally investigated. Ozone MNBs were then used to treat organics-contaminated water, and they showed remarkable cleanup efficiency. Column tests were also conducted to study the efficiency of ozone MNBs for organics-contaminated groundwater remediation. Based on the laboratory tests, field monitoring was conducted on a trichloroethylene (TCE)-contaminated site. The results showed that ozone MNBs can greatly improve remediation efficiency and represent an innovative technology for in situ remediation of organics-contaminated groundwater. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  14. Fate of return activated sludge after ozonation: an optimization study for sludge disintegration.

    Science.gov (United States)

    Demir, Ozlem; Filibeli, Ayse

    2012-09-01

    The effects of ozonation on sludge disintegration should be investigated before the application of ozone during biological treatment, in order to minimize excess sludge production. In this study, changes in sludge and supernatant after ozonation of return activated sludge were investigated for seven different ozone doses. The optimum ozone dose to avoid inhibition of ozonation and high ozone cost was determined in terms of disintegration degree as 0.05 g O3/gTS. Suspended solid and volatile suspended solid concentrations of sludge decreased by 77.8% and 71.6%, respectively, at the optimum ozone dose. Ozonation significantly decomposed sludge flocs. The release of cell contents was proved by the increase of supernatant total nitrogen (TN) and phosphorus (TP). While TN increased from 7 mg/L to 151 mg/L, TP increased from 8.8 to 33 mg/L at the optimum ozone dose. The dewaterability and filterability characteristics of the ozonated sludge were also examined. Capillary suction time increased with increasing ozone dosage, but specific resistance to filtration increased to a specific value and then decreased dramatically. The particle size distribution changed significantly as a result of floc disruption at an optimum dose of 0.05 gO3/gTS.

  15. CONTRIBUTION TO INDOOR OZONE LEVELS OF AN OZONE GENERATOR

    Science.gov (United States)

    This report gives results of a study of a commonly used commercially available ozone generator, undertaken to determine its impact on indoor ozone levels. xperiment were conducted in a typical mechanically ventilated office and in a test house. he generated ozone and the in-room ...

  16. Electron beam process design for the treatment of wastes and economic feasibility of the process

    Energy Technology Data Exchange (ETDEWEB)

    Cleland, M R; Fernald, R A; Malcof, S R [High Voltage Engineering Corp., Burlington, MA (USA)

    1984-01-01

    Electron beam irradiation is a practical and economical method to disinfect liquid municipal sludges at high throughput rates. Demonstration facilities have been built in Boston and Miami with treatment capacities of 170,000 gallons per day (650 cubic meters per day) for a minimum dose of 400 kilorads. The electron treatment process is described in some detail. Capital and operating cost estimates are given for continuous sludge disinfection. Total costs for liquid sludge are $7.50 per 1000 gallons. Equivalent costs for residual sewage solids are $50.00 per metric ton. Economic comparisons are made between electron accelerators and gamma-ray sources for liquid and dewatered sludge. The possibilities of treating wastewater and drinking water with high-energy electrons are also reviewed.

  17. A 3D technique for simulation of irregular electron treatment fields using a digital camera

    International Nuclear Information System (INIS)

    Bassalow, Roustem; Sidhu, Narinder P.

    2003-01-01

    Cerrobend inserts, which define electron field apertures, are manufactured at our institution using perspex templates. Contours are reproduced manually on these templates at the simulator from the field outlines drawn on the skin or mask of a patient. A previously reported technique for simulation of electron treatment fields uses a digital camera to eliminate the need for such templates. However, avoidance of the image distortions introduced by non-flat surfaces on which the electron field outlines were drawn could only be achieved by limiting the application of this technique to surfaces which were flat or near flat. We present a technique that employs a digital camera and allows simulation of electron treatment fields contoured on an anatomical surface of an arbitrary three-dimensional (3D) shape, such as that of the neck, extremities, face, or breast. The procedure is fast, accurate, and easy to perform

  18. Ozone-depleting Substances (ODS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — This site includes all of the ozone-depleting substances (ODS) recognized by the Montreal Protocol. The data include ozone depletion potentials (ODP), global warming...

  19. Air Quality Guide for Ozone

    Science.gov (United States)

    GO! Local Air Quality Conditions Zip Code: State : My Current Location Air Quality Guide for Ozone Ground-level ozone is one of our nation’s most common air pollutants. Use the chart below to help reduce ...

  20. Health Effects of Ozone Pollution

    Science.gov (United States)

    Inhaling ozone can cause coughing, shortness of breath, worse asthma or bronchitis symptoms, and irritation and damage to airways.You can reduce your exposure to ozone pollution by checking air quality where you live.

  1. Treatability study of the effluent containing reactive blue 21 dye by ozonation and the mass transfer study of ozone

    Science.gov (United States)

    Velpula, Priyadarshini; Ghuge, Santosh; Saroha, Anil K.

    2018-04-01

    Ozonation is a chemical treatment process in which ozone reacts with the pollutants present in the effluent by infusion of ozone into the effluent. This study includes the effect of various parameters such as inlet ozone dose, pH of solution and initial concentration of dye on decolorization of dye in terms CRE. The maximum CRE of 98.62% with the reaction rate constant of 0.26 min-1 is achieved in 18 minutes of reaction time at inlet ozone dose of 11.5 g/m3, solution pH of 11 and 30 mg/L of initial concentration of dye. The presence of radical scavenger (Tertiary Butyl Alcohol) suppressed the CRE from 98.62% to 95.4% at high pH values indicates that the indirect mechanism dominates due to the presence of hydroxyl radicals which are formed by the decomposition of ozone. The diffusive and convective mass transfer coefficients of ozone are calculated as 1.78 × 10-5 cm2/sec and 0.075 min-1. It is observed that the fraction of resistance offered by liquid is very much high compared to gas phase indicates that the ozonation is a liquid phase mass transfer controlled operation.

  2. Ozone therapy in dentistry. A brief review for physicians.

    Science.gov (United States)

    Domb, William C

    2014-10-31

    The 21(st) century dental practice is quite dynamic. New treatment protocols and new materials are being developed at a rapid pace. Ozone dental therapy falls into the category of new treatment protocols in dentistry, yet ozone is not new at all. Ozone therapy is already a major treatment modality in Europe, South America and a number of other countries. What is provided here will not be an exhaustive scientific treatise so much as a brief general introduction into what dentists are now doing with ozone therapies and the numerous oral/systemic links that make this subject so important for physicians so that, ultimately, they may serve their patients more effectively and productively.

  3. Modulated electron radiotherapy treatment planning using a photon multileaf collimator for post-mastectomized chest walls

    International Nuclear Information System (INIS)

    Salguero, Francisco Javier; Palma, Bianey; Arrans, Rafael; Rosello, Joan; Leal, Antonio

    2009-01-01

    Background and purpose: To evaluate the feasibility of using a photon MLC (xMLC) for modulated electron radiotherapy treatment (MERT) as an alternative to conventional post-mastectomy chest wall (CW) irradiation. A Monte Carlo (MC) based planning system was developed to overcome the inaccuracy of the 'pencil beam' algorithm. MC techniques are known to accurately calculate the dose distributions of electron beams, allowing the explicit simulation of electron interactions within the MLC. Materials and methods: Four real clinical CW cases were planned using MERT which were compared with the conventional electron treatments based on blocks and by a straightforward approach using the MLC, and not the blocks (as an intermediate step to MERT) to shape the same segments with SSD between 60 and 70 cm depending on PTV size. MC calculations were verified with an array of ionization chambers and radiochromic films in a solid water phantom. Results: Tests based on gamma analysis between MC dose distributions and radiochromic film measurements showed an excellent agreement. Differences in the absolute dose measured with a plane-parallel chamber at a reference point were below 3% for all cases. MERT solution showed a better PTV coverage and a significant reduction of the doses to the organs at risk (OARs). Conclusion: MERT can effectively improve the current electron treatments by obtaining a better PTV coverage and sparing healthy tissues. More directly, block-shaped treatments could be replaced by MLC-shaped non-modulated segments providing similar results.

  4. Ozone bioindicator sampling and estimation

    Science.gov (United States)

    Gretchen C, Smith; William D. Smith; John W. Coulston

    2007-01-01

    Ozone is an important forest stressor that has been measured at known phytotoxic levels at forest locations across the United States. The percent forest exhibiting negative impacts from ozone air pollution is one of the Montreal Process indicators of forest health and vitality. The ozone bioindicator data of the U.S. Forest Service Forest Inventory and Analysis Program...

  5. Ozonated Olive Oils and Troubles

    Directory of Open Access Journals (Sweden)

    Bulent Uysal

    2014-04-01

    Full Text Available One of the commonly used methods for ozone therapy is ozonated oils. Most prominent type of used oils is extra virgin olive oil. But still, each type of unsaturated oils may be used for ozonation. There are a lot of wrong knowledge on the internet about ozonated oils and its use as well. Just like other ozone therapy studies, also the studies about ozone oils are inadequate to avoid incorrect knowledge. Current data about ozone oil and its benefits are produced by supplier who oversees financial interests and make misinformation. Despite the rapidly increasing ozone oil sales through the internet, its quality and efficacy is still controversial. Dozens of companies and web sites may be easily found to buy ozonated oil. But, very few of these products are reliable, and contain sufficiently ozonated oil. This article aimed to introduce the troubles about ozonated oils and so to inform ozonated oil users. [J Intercult Ethnopharmacol 2014; 3(2.000: 49-50

  6. Disappearing threat to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Gribbin, J

    1979-02-15

    Concern that human activities might disturb the dynamic natural equilibrium of the ozone layer has stemmed from the fact that this layer plays a key part in the ecology of the earth by absorbing harmful ultraviolet radiation which would otherwise penetrate to the ground. Apparently, however, a decline of as much at 15% in total global ozone would have very little effect on climate. A 50% reduction would produce a marked cooling of the stratosphere at 40 km altitude over the tropics, but barely detectable changes in temperature and rainfall in the lower atmosphere. Therefore, biological effects of more uv light at ground level is the only hazard associated with ozone depletion on the scale which might take place.

  7. SU-F-P-03: Management of Time to Treatment Inititation: Case for An Electronic Whiteboard

    Energy Technology Data Exchange (ETDEWEB)

    Adnani, N [The Global Medical Physics Institute, Irvine, CA (United States)

    2016-06-15

    Purpose: To determine if data mining of an electronic whiteboard improves the management of the Time to Treatment Initiation (TTI) in radiation oncology. Methods: An electronic whiteboard designed to help in managing the planning workflow and improves communication regarding patient planning progress was used to record the dates at which each phase of the planning process began or completed. These are CT Sim date, Plan Start, Physician Review, Physicist Review, Approval for Treatment Delivery, Setup or Verification of Simulation. Results: During clinical implementation, the electronic whiteboard was able to fulfill its primary objective of providing a transparent account of the planning progress of each patient. Peer pressure also meant that individual tasks, such as contouring, were easily brought to the attention of the responsible party and prioritized accordingly. Data mining to analyze the electronic whiteboard per patient (figure 1), per diagnosis (figure 2), per treatment modality (figure 3), per physician (figure 4), per planner (figure 5), etc., added another sophisticated tool in the management of Time to Treatment Initiation without compromising quality of the plans being generated. A longer than necessary time between CT Sim and Plan Start can be discussed among the members of the treatment team as an indication of inadequate/outdated CT Simulator, Contouring Tools, Image Fusion Tools, Other Imaging Studies (MRI, PET/CT) performed, etc. The same for the Plan Start to Physician Review where an extended time than expected may be due unrealistic planning goals, limited planning system features, etc. Conclusion: An Electronic Whiteboard in radiation oncology is not only helping with organizing planning workflow, it is also a potent tool that can be used to reduce the Time to Treatment Initiation by providing the clinic with hard data about the duration of each phase treatment planning as a function of different variable affecting the planning process. The

  8. SU-F-P-03: Management of Time to Treatment Inititation: Case for An Electronic Whiteboard

    International Nuclear Information System (INIS)

    Adnani, N

    2016-01-01

    Purpose: To determine if data mining of an electronic whiteboard improves the management of the Time to Treatment Initiation (TTI) in radiation oncology. Methods: An electronic whiteboard designed to help in managing the planning workflow and improves communication regarding patient planning progress was used to record the dates at which each phase of the planning process began or completed. These are CT Sim date, Plan Start, Physician Review, Physicist Review, Approval for Treatment Delivery, Setup or Verification of Simulation. Results: During clinical implementation, the electronic whiteboard was able to fulfill its primary objective of providing a transparent account of the planning progress of each patient. Peer pressure also meant that individual tasks, such as contouring, were easily brought to the attention of the responsible party and prioritized accordingly. Data mining to analyze the electronic whiteboard per patient (figure 1), per diagnosis (figure 2), per treatment modality (figure 3), per physician (figure 4), per planner (figure 5), etc., added another sophisticated tool in the management of Time to Treatment Initiation without compromising quality of the plans being generated. A longer than necessary time between CT Sim and Plan Start can be discussed among the members of the treatment team as an indication of inadequate/outdated CT Simulator, Contouring Tools, Image Fusion Tools, Other Imaging Studies (MRI, PET/CT) performed, etc. The same for the Plan Start to Physician Review where an extended time than expected may be due unrealistic planning goals, limited planning system features, etc. Conclusion: An Electronic Whiteboard in radiation oncology is not only helping with organizing planning workflow, it is also a potent tool that can be used to reduce the Time to Treatment Initiation by providing the clinic with hard data about the duration of each phase treatment planning as a function of different variable affecting the planning process. The

  9. The Effects of Acid Passivation, Tricresyl Phosphate Pre-Soak, and UV/Ozone Treatment on the Tribology of Perfluoropolyether-Lubricated 440C Stainless Steel Couples

    Science.gov (United States)

    Shogrin, Bradley A.; Jones, William R., Jr.; Herrera-Fierro, Pilar

    1997-01-01

    The boundary-lubrication performance of perfluoropolyether (PFPE) thin films in the presence of passivated 440 C stainless steel is presented. The study utilized a standard ball-on-disc tribometer. Stainless steel surfaces were passivated with one of four techniques: 1) submersion in a chromic acid bath for 30 minutes at 46 C, 2) submersion in a chromic acid bath for 60 minutes at 56 C, 3) submersion in a tricresyl phosphate (TCP) bath for 2 days at 107 C, or 4) UV/Ozone treated for 15 minutes. After passivation, each disc had a 400 A film of PFPE (hexafluoropropene oxide) applied to it reproducibly (+/- 20%) and uniformly (+/- 15%) using a film deposition device. The lifetimes of these films were quantified by measuring the number of sliding wear cycles required to induce an increase in the friction coefficient from an initial value characteristic of the lubricated wear couple to a final, or failure value, characteristic of an unlubricated, unpassivated wear couple. The lubricated lifetime of the 440 C couple was not altered as a result of the various passivation techniques. The resulting surface chemistry of each passivation technique was examined using X-ray Photoelectron Spectroscopy (XPS). It was found that chromic acid passivation altered the Cr to Fe ratio of the surface. TCP passivation resulted in a FePO4 layer on the surface, while UV/Ozone passivation only removed the carbonaceous contamination layer. None of the passivation techniques were found to dramatically increase the oxide film thickness.

  10. A new diagnostic for tropospheric ozone production

    Science.gov (United States)

    Edwards, Peter M.; Evans, Mathew J.

    2017-11-01

    Tropospheric ozone is important for the Earth's climate and air quality. It is produced during the oxidation of organics in the presence of nitrogen oxides. Due to the range of organic species emitted and the chain-like nature of their oxidation, this chemistry is complex and understanding the role of different processes (emission, deposition, chemistry) is difficult. We demonstrate a new methodology for diagnosing ozone production based on the processing of bonds contained within emitted molecules, the fate of which is determined by the conservation of spin of the bonding electrons. Using this methodology to diagnose ozone production in the GEOS-Chem chemical transport model, we demonstrate its advantages over the standard diagnostic. We show that the number of bonds emitted, their chemistry and lifetime, and feedbacks on OH are all important in determining the ozone production within the model and its sensitivity to changes. This insight may allow future model-model comparisons to better identify the root causes of model differences.

  11. A new diagnostic for tropospheric ozone production

    Directory of Open Access Journals (Sweden)

    P. M. Edwards

    2017-11-01

    Full Text Available Tropospheric ozone is important for the Earth's climate and air quality. It is produced during the oxidation of organics in the presence of nitrogen oxides. Due to the range of organic species emitted and the chain-like nature of their oxidation, this chemistry is complex and understanding the role of different processes (emission, deposition, chemistry is difficult. We demonstrate a new methodology for diagnosing ozone production based on the processing of bonds contained within emitted molecules, the fate of which is determined by the conservation of spin of the bonding electrons. Using this methodology to diagnose ozone production in the GEOS-Chem chemical transport model, we demonstrate its advantages over the standard diagnostic. We show that the number of bonds emitted, their chemistry and lifetime, and feedbacks on OH are all important in determining the ozone production within the model and its sensitivity to changes. This insight may allow future model–model comparisons to better identify the root causes of model differences.

  12. OZONE BLEACHING AT NEUTRAL PH – A NEW CONCEPT

    Directory of Open Access Journals (Sweden)

    Fernando de Carvalho

    2010-08-01

    Full Text Available The effect of medium consistency ozone stage pH was evaluated for brown and oxygen delignified eucalyptus kraft pulp samples obtained from VCP - Luiz Antônio pulp mill. These samples were used as such or previously treated with the hot acid stage (A. The main objective of this study was to determine the viability of increasing the ozone stage pH aiming at decreasing bleaching variable costs. The ozone stage was studied in the pH range of 2.5-9.0, taking into account some important variables which affect ozone bleaching: (1 pulp kappa number entering the ozone stage, (2 reactivity of ozone towards lignin versus hexenuronic acids (HexA´s, (3 pulp treatments prior to ozone stage (acid hydrolysis, and (4 pulp treatments after the ozone stage (extraction or a chlorine dioxide stage.  Therefore, the impact of ozone stage pH was investigated in bleaching process such as Z/DEop vs AZ/DEop, Z/DEopD vs AZ/DEopD, Z/E vs AZ/E. The results were interpreted based on ozone stage efficiency and selectivity, and overall bleaching performance measured by the total bleaching chemical consumption required to achieve full brightness, pulp quality and environmental impact. It was concluded that the increase of ozone stage pH from 2.5 to 7.0 has a slightly negative impact on the efficiency and selectivity, measured after Z/DEop sequence, but this effect is not expressive in the end of Z/DEopD bleaching sequence. The increase of ozone stage pH from 2.5 to 7.0 in the sequence Z/DEopD is cost-effective at industrial level because it represents expressive reduction of sulphuric acid and caustic soda demand for pH control in the bleaching plant. These gain areas achieved without any significant changes in pulp quality and effluent load discharge. Nevertheless, the increase of ozone stage pH from 2.5 to 7.0 has a very high negative impact on the efficiency and selectivity for the Z/E and AZ/E processes and it is not recommended in such cases.

  13. Physicochemical patterns of ozone absorption by wood

    Science.gov (United States)

    Mamleeva, N. A.; Lunin, V. V.

    2016-11-01

    Results from studying aspen and pine wood ozonation are presented. The effect the concentration of ozone, the reagent residence time, and the content of water in a sample of wood has on ozone consumption rate and ozone demand are analyzed. The residence time is shown to determine the degree of ozone conversion degree and the depth of substrate destruction. The main patterns of ozone absorption by wood with different moisture content are found. Ways of optimizing the ozonation of plant biomass are outlined.

  14. Electron beam treatment of organic pollutants contained in gaseous streams. 1. RCM report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Volatile Organic Compounds (VOC) and Polyaromatic Hydrocarbons (PAH) are emitted in different processes, mostly combustion-based ones applied in power, chemical and metallurgical industries, municipal wastes incineration, etc. Many of them are persistent in environment, so called Persistent Organic Pollutants (POPs). They are responsible for ozone layer depletion, ground level and photochemical smog formation, contribute to the greenhouse effect, most of them being carcinogenic or/and mutagenic. Some tests performed in different countries have shown that electron beam technology can be a promising technique in these applications. Good removing efficiency for chlorohydrocarbons, dioxins and PAH was demonstrated in the laboratory scale. Different hybrid techniques like eb/absorption or eb/catalysis were studied as well. However, due to the different product formation, this technique should be studied carefully further concerning process mechanism, analyses of products and possible technical solution applications. The present CRP aiming at development of laboratory and pilot plant methodologies for comparative evaluation of degradation effects of organic pollutants in gaseous phase. Theoretical and experimental investigations of the mechanisms of the processes are part of the research work. Limitation of formation of toxic byproducts, modification of physical and chemical properties, application of hybrid processes (eb/catalytist) are important topics for further development under the CRP. The CRP has been launched with the objectives of developing analytical techniques for better understanding of degradation effects of organic pollutants in gaseous phase and technologies (processing conditions) to control these emissions. It is anticipated that through collaborative and cooperative research efforts of the participants, new analytical methods to study the process and strategies to apply electron beam to address these emissions will be developed. The executive summary

  15. Electron beam treatment of organic pollutants contained in gaseous streams. 1. RCM report

    International Nuclear Information System (INIS)

    2005-01-01

    Volatile Organic Compounds (VOC) and Polyaromatic Hydrocarbons (PAH) are emitted in different processes, mostly combustion-based ones applied in power, chemical and metallurgical industries, municipal wastes incineration, etc. Many of them are persistent in environment, so called Persistent Organic Pollutants (POPs). They are responsible for ozone layer depletion, ground level and photochemical smog formation, contribute to the greenhouse effect, most of them being carcinogenic or/and mutagenic. Some tests performed in different countries have shown that electron beam technology can be a promising technique in these applications. Good removing efficiency for chlorohydrocarbons, dioxins and PAH was demonstrated in the laboratory scale. Different hybrid techniques like eb/absorption or eb/catalysis were studied as well. However, due to the different product formation, this technique should be studied carefully further concerning process mechanism, analyses of products and possible technical solution applications. The present CRP aiming at development of laboratory and pilot plant methodologies for comparative evaluation of degradation effects of organic pollutants in gaseous phase. Theoretical and experimental investigations of the mechanisms of the processes are part of the research work. Limitation of formation of toxic byproducts, modification of physical and chemical properties, application of hybrid processes (eb/catalytist) are important topics for further development under the CRP. The CRP has been launched with the objectives of developing analytical techniques for better understanding of degradation effects of organic pollutants in gaseous phase and technologies (processing conditions) to control these emissions. It is anticipated that through collaborative and cooperative research efforts of the participants, new analytical methods to study the process and strategies to apply electron beam to address these emissions will be developed. The executive summary

  16. Total skin electron therapy treatment verification: Monte Carlo simulation and beam characteristics of large non-standard electron fields

    International Nuclear Information System (INIS)

    Pavon, Ester Carrasco; Sanchez-Doblado, Francisco; Leal, Antonio; Capote, Roberto; Lagares, Juan Ignacio; Perucha, Maria; Arrans, Rafael

    2003-01-01

    Total skin electron therapy (TSET) is a complex technique which requires non-standard measurements and dosimetric procedures. This paper investigates an essential first step towards TSET Monte Carlo (MC) verification. The non-standard 6 MeV 40 x 40 cm 2 electron beam at a source to surface distance (SSD) of 100 cm as well as its horizontal projection behind a polymethylmethacrylate (PMMA) screen to SSD = 380 cm were evaluated. The EGS4 OMEGA-BEAM code package running on a Linux home made 47 PCs cluster was used for the MC simulations. Percentage depth-dose curves and profiles were calculated and measured experimentally for the 40 x 40 cm 2 field at both SSD = 100 cm and patient surface SSD = 380 cm. The output factor (OF) between the reference 40 x 40 cm 2 open field and its horizontal projection as TSET beam at SSD = 380 cm was also measured for comparison with MC results. The accuracy of the simulated beam was validated by the good agreement to within 2% between measured relative dose distributions, including the beam characteristic parameters (R 50 , R 80 , R 100 , R p , E 0 ) and the MC calculated results. The energy spectrum, fluence and angular distribution at different stages of the beam (at SSD = 100 cm, at SSD = 364.2 cm, behind the PMMA beam spoiler screen and at treatment surface SSD = 380 cm) were derived from MC simulations. Results showed a final decrease in mean energy of almost 56% from the exit window to the treatment surface. A broader angular distribution (FWHM of the angular distribution increased from 13deg at SSD 100 cm to more than 30deg at the treatment surface) was fully attributable to the PMMA beam spoiler screen. OF calculations and measurements agreed to less than 1%. The effect of changing the electron energy cut-off from 0.7 MeV to 0.521 MeV and air density fluctuations in the bunker which could affect the MC results were shown to have a negligible impact on the beam fluence distributions. Results proved the applicability of using MC

  17. A voltammetric electronic tongue as tool for water quality monitoring in wastewater treatment plants.

    Science.gov (United States)

    Campos, Inmaculada; Alcañiz, Miguel; Aguado, Daniel; Barat, Ramón; Ferrer, José; Gil, Luis; Marrakchi, Mouna; Martínez-Mañez, Ramón; Soto, Juan; Vivancos, José-Luis

    2012-05-15

    The use of a voltammetric electronic tongue as tool for the prediction of concentration levels of certain water quality parameters from influent and effluent wastewater from a Submerged Anaerobic Membrane Bioreactor pilot plant applied to domestic wastewater treatment is proposed here. The electronic tongue consists of a set of noble (Au, Pt, Rh, Ir, and Ag) and non-noble (Ni, Co and Cu) electrodes that were housed inside a stainless steel cylinder which was used as the body of the electronic tongue system. As a previous step an electrochemical study of the response of the ions sulphate, orthophosphate, acetate, bicarbonate and ammonium was carried out in water using the electrodes contained in the electronic tongue. The second part of the work was devoted to the application of the electronic tongue to the characterization of the influent and effluent waters from the wastewater treatment plant. Partial Least Squares analysis was used to obtain a correlation between the data from the tongue and the pollution parameters measured in the laboratory such as soluble chemical oxygen demand (CODs), soluble biological oxygen demand (BODs), ammonia (NH(4)-N), orthophosphate (PO(4)-P), Sulphate (SO(4)-S), acetic acid (HAC) and alkalinity (Alk). A total of 28 and 11 samples were used in the training and the validation steps, respectively, for both influent and effluent water samples. The electronic tongue showed relatively good predictive power for the determination of BOD, COD, NH(4)-N, PO(4)-P, SO(4)-S, and Alk. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Monte Carlo treatment planning with modulated electron radiotherapy: framework development and application

    Science.gov (United States)

    Alexander, Andrew William

    Within the field of medical physics, Monte Carlo radiation transport simulations are considered to be the most accurate method for the determination of dose distributions in patients. The McGill Monte Carlo treatment planning system (MMCTP), provides a flexible software environment to integrate Monte Carlo simulations with current and new treatment modalities. A developing treatment modality called energy and intensity modulated electron radiotherapy (MERT) is a promising modality, which has the fundamental capabilities to enhance the dosimetry of superficial targets. An objective of this work is to advance the research and development of MERT with the end goal of clinical use. To this end, we present the MMCTP system with an integrated toolkit for MERT planning and delivery of MERT fields. Delivery is achieved using an automated "few leaf electron collimator" (FLEC) and a controller. Aside from the MERT planning toolkit, the MMCTP system required numerous add-ons to perform the complex task of large-scale autonomous Monte Carlo simulations. The first was a DICOM import filter, followed by the implementation of DOSXYZnrc as a dose calculation engine and by logic methods for submitting and updating the status of Monte Carlo simulations. Within this work we validated the MMCTP system with a head and neck Monte Carlo recalculation study performed by a medical dosimetrist. The impact of MMCTP lies in the fact that it allows for systematic and platform independent large-scale Monte Carlo dose calculations for different treatment sites and treatment modalities. In addition to the MERT planning tools, various optimization algorithms were created external to MMCTP. The algorithms produced MERT treatment plans based on dose volume constraints that employ Monte Carlo pre-generated patient-specific kernels. The Monte Carlo kernels are generated from patient-specific Monte Carlo dose distributions within MMCTP. The structure of the MERT planning toolkit software and

  19. Chemical and Spectral Characterization of The Ozonation Products of κ-Carrageenan

    Directory of Open Access Journals (Sweden)

    Prasetyaningrum Aji

    2018-01-01

    Full Text Available Kappa (κ- carrageenan oligomers are known to have several biological activities. Recent progress in the development of modified κ-carrageenan has resulted low molecular of κ-carrageenan. Ozone is a powerful oxidant and considered for depolymerization of κ-carrageenan. However, few studies have investigated the changes in κ-carrageenan properties associated with ozone treatment. This study would investigate on the changes in chemical structure after ozonation process. The experiments were carried out in a glass reactor equipped with an ozone bubble diffuser. Ozone with concentration of 80 ± 2 was bubbled into the solution. The ozone treatment was conducted at different times, i.e., 0 (control, 5, 10, 15, and 20 minutes. The experiments were conducted at pH 7 and constant stirring speed (200 rpm. Ozone-treated κ-carrageenan was dried at 60 ºC for 24 h in a forced air oven. The chemical and spectral analyses of κ-carrageenan after ozonation process were carried out using UV-Vis and FT-IR spectroscopy. These changes are seen in the UV spectra as a high intensity of absorbance peak at 290 nm. It is shows that ozonation of κ-carrageenan leads to some chemical changes such as the formation of carbonyl, carboxyl or double bonds.The FT-IR spectra reveals that the chemical structure of degraded κ-carrageenan, in term of sulfate content, is only slightly affected by the ozone treatment.

  20. Ozone dosing alters the biological potential and therapeutic outcomes of plasma rich in growth factors.

    Science.gov (United States)

    Anitua, E; Zalduendo, M M; Troya, M; Orive, G

    2015-04-01

    Until now, ozone has been used in a rather empirical way. This in-vitro study investigates, for the first time, whether different ozone treatments of plasma rich in growth factors (PRGF) alter the biological properties and outcomes of this autologous platelet-rich plasma. Human plasma rich in growth factors was treated with ozone using one of the following protocols: a continuous-flow method; or a syringe method in which constant volumes of ozone and PRGF were mixed. In both cases, ozone was added before, during and after the addition of calcium chloride. Three ozone concentrations, of the therapeutic range 20, 40 and 80 μg/mL, were tested. Fibrin clot properties, growth factor content and the proliferative effect on primary osteoblasts and gingival fibroblasts were evaluated. Ozone treatment of PRGF using the continuous flow protocol impaired formation of the fibrin scaffold, drastically reduced the levels of growth factors and significantly decreased the proliferative potential of PRGF on primary osteoblasts and gingival fibroblasts. In contrast, treatment of PRGF with ozone using the syringe method, before, during and after the coagulation process, did not alter the biological outcomes of the autologous therapy. These findings suggest that ozone dose and the way that ozone combines with PRGF may alter the biological potential and therapeutic outcomes of PRGF. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Measurement of Ozone Production Sensor

    Directory of Open Access Journals (Sweden)

    M. Cazorla

    2010-05-01

    Full Text Available A new ambient air monitor, the Measurement of Ozone Production Sensor (MOPS, measures directly the rate of ozone production in the atmosphere. The sensor consists of two 11.3 L environmental chambers made of UV-transmitting Teflon film, a unit to convert NO2 to O3, and a modified ozone monitor. In the sample chamber, flowing ambient air is exposed to the sunlight so that ozone is produced just as it is in the atmosphere. In the second chamber, called the reference chamber, a UV-blocking film over the Teflon film prevents ozone formation but allows other processes to occur as they do in the sample chamber. The air flows that exit the two chambers are sampled by an ozone monitor operating in differential mode so that the difference between the two ozone signals, divided by the exposure time in the chambers, gives the ozone production rate. High-efficiency conversion of NO2 to O3 prior to detection in the ozone monitor accounts for differences in the NOx photostationary state that can occur in the two chambers. The MOPS measures the ozone production rate, but with the addition of NO to the sampled air flow, the MOPS can be used to study the sensitivity of ozone production to NO. Preliminary studies with the MOPS on the campus of the Pennsylvania State University show the potential of this new technique.

  2. Total skin electron therapy as treatment for epitheliotropic lymphoma in a dog.

    Science.gov (United States)

    Santoro, Domenico; Kubicek, Lyndsay; Lu, Bo; Craft, William; Conway, Julia

    2017-04-01

    Mycosis fungoides (MF) is an uncommon cutaneous neoplasm in dogs. Treatment options are limited. Total skin electron therapy (TSET) has been suggested as a possible therapy for canine MF. To describe the use of TSET as palliative treatment for MF in a dog. An adult dog, previously diagnosed with nonepidermolytic ichthyosis, was presented with generalized erythroderma, alopecia and erosions. Histopathology revealed a densely cellular, well-demarcated, unencapsulated infiltrate extending from the epidermis to the mid-dermis compatible with MF. The infiltrate exhibited epitheliotropism multifocally for the epidermis, infundibula and adnexa. Due to a lack of response to chemotherapy, TSET was elected. Six megavoltage electrons were delivered using a 21EX Varian linear accelerator. A dose of 6 Gy was delivered to the skin surface and a 100 cm skin to surface distance was used for dog setup. The treatment time for the cranial half treatment was 3 h. The treatment was divided in two sessions (cranial and caudal halves of the body) 15 days apart. Clinical and histopathological complete remission was achieved and the dog was kept in remission with no additional treatments for 19 months before relapse and development of Sézary syndrome. To the best of the authors' knowledge, this is the first case reporting the use of TSET for medically refractory canine MF with post treatment follow-up. This case suggests that the use of TSET may be an effective palliative treatment for canine MF. © 2017 ESVD and ACVD.

  3. Influence of pulsed electron beam treatment on microstructure and properties of TA15 titanium alloy

    International Nuclear Information System (INIS)

    Gao Yukui

    2013-01-01

    Highlights: ► The hardness changes were determined by nanoindention method. ► The surface modification by pulsed electron beam treatment was investigated. ► The mechanism was analyzed based on XRD and TEM investigations. ► The modification effects were focused at the surface layer hardness. - Abstract: The surface of TA15 titanium alloy was modified by pulsed electron beam and the hardness distribution along the treated surface layer was investigated by nanoindent technology. The grade characteristics were therefore analyzed by studying the distribution of hardness along surface layer of specimens. Moreover, the microstructure was investigated by OM, XRD and TEM techniques. Furthermore, the correlation of hardness to microstructure was analyzed. The results show that the grade fine grain microstructure is formed in the upper surface layer and the temperature grade or heat effect caused by pulsed electron beam treatment is the main reason to form grade fine grain microstructure in the surface layer.

  4. Influence of the curve density relative electron in dosimetry clinic in treatments stereo tactics

    International Nuclear Information System (INIS)

    Moreno Saiz, C.; Benitez Villegas, E. M.; Casado Villalon, F. J.; Parra Osorio, V.; Bodineau Gil, C.; Garcia Pareja, S.

    2013-01-01

    The objective of this study is to analyze the difference between clinical dosimetry in the treatments with radiosurgery and stereotactic radiotherapy fractional obtained from the relative Electron density curve (Schneider 1996) tabulated and provided with the scanner's radiation therapy. (Author)

  5. Developing an electronic health record (EHR) for methadone treatment recording and decision support.

    LENUS (Irish Health Repository)

    Xiao, Liang

    2011-02-01

    In this paper, we give an overview of methadone treatment in Ireland and outline the rationale for designing an electronic health record (EHR) with extensibility, interoperability and decision support functionality. Incorporating several international standards, a conceptual model applying a problem orientated approach in a hierarchical structure has been proposed for building the EHR.

  6. The role of phantom and treatment head generated bremsstrahlung in high-energy electron beam dosimetry

    International Nuclear Information System (INIS)

    Sorcini, B.B.; Hyoedynmaa, S.; Brahme, A.

    1996-01-01

    An analytical expression has been derived for the phantom generated bremsstrahlung photons in plane-parallel monoenergetic electron beams normally incident on material of any atomic number (Be, H 2 O, Al, Cu and U). The expression is suitable for the energy range from 1 to 50 MeV and it is solely based on known scattering power and radiative and collision stopping power data for the material at the incident electron energy. The depth dose distribution due to the bremsstrahlung generated by the electrons in the phantom is derived by convolving the bremsstrahlung energy fluence produced in the phantom with a simple analytical energy deposition kernel. The kernel accounts for both electrons and photons set in motion by the bremsstrahlung photons. The energy loss by the primary electrons, the build-up of the electron fluence and the generation, attenuation and absorption of bremsstrahlung photons are all taken into account in the analytical formula. The longitudinal energy deposition kernel is derived analytically and it is consistent with both the classical biexponential relation describing the photon depth dose distribution and the exponential attenuation of the primary photons. For comparison Monte Carlo calculated energy deposition distributions using ITS3 code were used. Good agreement was found between the results with the analytical expression and the Monte Carlo calculation. For tissue equivalent materials, the maximum total energy deposition differs by less than 0.2% from Monte Carlo calculated dose distributions. The result can be used to estimate the depth dependence of phantom generated bremsstrahlung in different materials in therapeutic electron beams and the bremsstrahlung production in different electron absorbers such as scattering foils, transmission monitors and photon and electron collimators. By subtracting the phantom generated bremsstrahlung from the total bremsstrahlung background the photon contamination generated in the treatment head can be

  7. Surface treatment by the ion flow from electron beam generated plasma in the forevacuum pressure range

    Directory of Open Access Journals (Sweden)

    Klimov Aleksandr

    2018-01-01

    Full Text Available The paper presents research results of peculiarities of gas ion flows usage and their generation from large plasma formation (>50 sq.cm obtained by electron beam ionization of gas in the forevacuum pressure range. An upgraded source was used for electron beam generation, which allowed obtaining ribbon electron beam with no transmitting magnetic field. Absence of magnetic field in the area of ion flow formation enables to obtain directed ion flows without distorting their trajectories. In this case, independent control of current and ion energy is possible. The influence of electron beam parameters on the parameters of beam plasma and ion flow – current energy and density – was determined. The results of alumina ceramics treatment with a beam plasma ions flow are given.

  8. Effectiveness of electron irradiation as a quarantine treatment of cut flowers

    International Nuclear Information System (INIS)

    Hayashi, T.; Todoriki, S.; Nakakita, H.; Dohino, T.; Tanabe, K.

    1999-01-01

    The effects of electron beams on spider mite (Tetranychus urticae) and flour beetle (Tribolium freemani) were slightly smaller than those of gamma-rays. 'Soft-electrons' (low-energy electrons) at an energy of 170 keV inactivated eggs, larvae, pupae, and adults of the flour beetle. Electron beams at doses up to 400 Gy killed or sterilized all the pests for cut flowers tested; spider mite (Tetranychus urticae), mealybug (Pseudococcus comstocki), leaf miner (Liriomyza trifolii), thrips (Thrips palmi, Thrips tabaci), cutworm (Spodoptera litura), and aphid (Myzus persicae). Carnation, alstromeria, gladiolus, tulip, statice, stock, dendrobium, prairie gentian, oncidium, campanula, gloriosa, fern, gypsophila, freesia, lobelia, triteleia, and gerbera were resistant to radiation, while chrysanthemum, rose, lily, calla, antherium, sweet pea, and iris were sensitive. Radiation-induced deterioration of chrysanthemum could be prevented by post-irradiation treatment with commercial preservative solutions or sugar solutions. (author)

  9. Our Shrinking Ozone Layer

    Indian Academy of Sciences (India)

    Depletion of the ozone layer is therefore having significant effects on life on .... but there is always a net balance between the rate of formation and destruction ..... award of Commonwealth Fellowship during the present work and also being an ...

  10. The ozone monitoring instrument

    NARCIS (Netherlands)

    Levelt, P.F.; Oord, G.H.J. van den; Dobber, M.R.; Mälkki, A.; Visser, H.; Vries, J. de; Stammes, P.; Lundell, J.O.V.; Saari, H.

    2006-01-01

    The Ozone Monitoring Instrument (OMI) flies on the National Aeronautics and Space Adminsitration's Earth Observing System Aura satellite launched in July 2004. OMI is a ultraviolet/visible (UV/VIS) nadir solar backscatter spectrometer, which provides nearly global coverage in one day with a spatial

  11. Ozone, greenhouse effect

    International Nuclear Information System (INIS)

    Aviam, A.M.; Arthaut, R.

    1992-01-01

    This file is made of eight general papers on environment (climates under observation, research on photo-oxidizing pollution, scientific aspects of stratospheric ozone layer, urban engineering and environment, glory of public gardens, earths not very natural, darwinism and society, economical data on environment). (A.B.). refs., 3 tabs

  12. Revisiting Antarctic Ozone Depletion

    Science.gov (United States)

    Grooß, Jens-Uwe; Tritscher, Ines; Müller, Rolf

    2015-04-01

    Antarctic ozone depletion is known for almost three decades and it has been well settled that it is caused by chlorine catalysed ozone depletion inside the polar vortex. However, there are still some details, which need to be clarified. In particular, there is a current debate on the relative importance of liquid aerosol and crystalline NAT and ice particles for chlorine activation. Particles have a threefold impact on polar chlorine chemistry, temporary removal of HNO3 from the gas-phase (uptake), permanent removal of HNO3 from the atmosphere (denitrification), and chlorine activation through heterogeneous reactions. We have performed simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) employing a recently developed algorithm for saturation-dependent NAT nucleation for the Antarctic winters 2011 and 2012. The simulation results are compared with different satellite observations. With the help of these simulations, we investigate the role of the different processes responsible for chlorine activation and ozone depletion. Especially the sensitivity with respect to the particle type has been investigated. If temperatures are artificially forced to only allow cold binary liquid aerosol, the simulation still shows significant chlorine activation and ozone depletion. The results of the 3-D Chemical Transport Model CLaMS simulations differ from purely Lagrangian longtime trajectory box model simulations which indicates the importance of mixing processes.

  13. Growth of soybean at future tropospheric ozone concentrations decreases canopy evapotranspiration and soil water depletion

    Energy Technology Data Exchange (ETDEWEB)

    Bernacchi, Carl J., E-mail: bernacch@illinois.edu [Global Change and Photosynthesis Research Unit, United States Department of Agriculture Agricultural Research Service, Urbana, IL 61801 (United States); Institute for Genomic Biology and Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Leakey, Andrew D.B. [Institute for Genomic Biology and Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Kimball, Bruce A. [USDA-ARS US Arid-Land Agricultural Research Center, 21881 N. Cardon Lane, Maricopa, AZ 85238 (United States); Ort, Donald R. [Global Change and Photosynthesis Research Unit, United States Department of Agriculture Agricultural Research Service, Urbana, IL 61801 (United States); Institute for Genomic Biology and Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

    2011-06-15

    Tropospheric ozone is increasing in many agricultural regions resulting in decreased stomatal conductance and overall biomass of sensitive crop species. These physiological effects of ozone forecast changes in evapotranspiration and thus in the terrestrial hydrological cycle, particularly in intercontinental interiors. Soybean plots were fumigated with ozone to achieve concentrations above ambient levels over five growing seasons in open-air field conditions. Mean season increases in ozone concentrations ([O{sub 3}]) varied between growing seasons from 22 to 37% above background concentrations. The objective of this experiment was to examine the effects of future [O{sub 3}] on crop ecosystem energy fluxes and water use. Elevated [O{sub 3}] caused decreases in canopy evapotranspiration resulting in decreased water use by as much as 15% in high ozone years and decreased soil water removal. In addition, ozone treatment resulted in increased sensible heat flux in all years indicative of day-time increase in canopy temperature of up to 0.7 deg. C. - Highlights: > Globally, tropospheric ozone is currently and will likely continue to increase into the future. > We examine the impact of elevated ozone on water use by soybean at the SoyFACE research facility. > High ozone grown soybean had reduced rates of evapotranspiration and higher soil moisture. > Increases in ozone have the potential to impact the hydrologic cycle where these crops are grown. - Soybean grown in elevated concentrations of ozone is shown to evapotranspire less water compared with soybean canopies grown under current atmospheric conditions.

  14. Growth of soybean at future tropospheric ozone concentrations decreases canopy evapotranspiration and soil water depletion

    International Nuclear Information System (INIS)

    Bernacchi, Carl J.; Leakey, Andrew D.B.; Kimball, Bruce A.; Ort, Donald R.

    2011-01-01

    Tropospheric ozone is increasing in many agricultural regions resulting in decreased stomatal conductance and overall biomass of sensitive crop species. These physiological effects of ozone forecast changes in evapotranspiration and thus in the terrestrial hydrological cycle, particularly in intercontinental interiors. Soybean plots were fumigated with ozone to achieve concentrations above ambient levels over five growing seasons in open-air field conditions. Mean season increases in ozone concentrations ([O 3 ]) varied between growing seasons from 22 to 37% above background concentrations. The objective of this experiment was to examine the effects of future [O 3 ] on crop ecosystem energy fluxes and water use. Elevated [O 3 ] caused decreases in canopy evapotranspiration resulting in decreased water use by as much as 15% in high ozone years and decreased soil water removal. In addition, ozone treatment resulted in increased sensible heat flux in all years indicative of day-time increase in canopy temperature of up to 0.7 deg. C. - Highlights: → Globally, tropospheric ozone is currently and will likely continue to increase into the future. → We examine the impact of elevated ozone on water use by soybean at the SoyFACE research facility. → High ozone grown soybean had reduced rates of evapotranspiration and higher soil moisture. → Increases in ozone have the potential to impact the hydrologic cycle where these crops are grown. - Soybean grown in elevated concentrations of ozone is shown to evapotranspire less water compared with soybean canopies grown under current atmospheric conditions.

  15. Studies on the dose distribution and treatment technique of high energy electron beams

    International Nuclear Information System (INIS)

    Lee, D.H.; Chu, S.S.

    1978-01-01

    Some important properties of high energy electron beams from the linear accelerator, LMR-13, installed in the Yonsei Cancer Center were studied. The results of experimental studies on the problems associated with the 8, 10, and 12 MeV electron beam therapy were as followings; The ionization type dosemeters calibrated by 90 Sr standard source were suitable to the measurements of the outputs and the obsorbed doses in accuracy point of view, and dose measurements using ionization chambers were difficult when measuring doses in small field size and the regions of rapid fall off. The electron energies were measured precisely with an energy spectrometer, and the practical electron energy was calculated within 5% error in the maximum range of the high energy electron beam in water. The correcting factors of perturbated dose distributions owing to radiation field, energy, and materials of the treatment cone were checked and described systematically and thus the variation of dose distributions due to the non-homogeneities of tissues and slopping skin surfaces were completely compensated. The electron beams were adequately diffused using the scatterers, and minimized the bremsstrahlung, irradiation field size, and materials of scatterers. Thus, the therapeutic capacity with the limited electron energy could be extended by improving the dose distributions. (author)

  16. Disinfection technology with ozone for cryptosporidium; Cryptosporidium taisaku to shite no ozone shodoku gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Y.; Takahashi, K. [Fuji Electric Co. Ltd., Tokyo (Japan); Motoyama, N. [Fuji Electric Corporate Research and Development, Ltd., Kanagawa (Japan)

    1998-06-10

    Measures against Cryptosporidium parvum (C. parvum) in the waterworks are discussed. C. parvum is a pathogenic protozoan, and exists in the form of oocyst protected by a hard shell. It does not multiply in water or food, but does in human intestines and causes violent diarrhea and bellyache. A grave concern was created when many people were infected with the protozoan via tap water in Japan and the United States. Under such circumstances, ozone is used in an experiment to inactivate C. parvum. It is found that the C. parvum oocyst inactivation effect is evaluated by using a Ct value (disinfectant concentration Cmg/Ltimescontact time in minute) and that ozone treatment inactivates 90-99% of the protozoan. When various advanced water treatment technologies are being introduced for the purpose of serving safe and tasty water, the outcome of this study conveniently offers an ozone treatment method that will additionally inactivate pathogenic protozoa. Studies will be continued to elucidate the effects of factors of ozone treatment and water quality for the completion of an ideal disinfection process. Reference is made to an example of disinfection work implemented at a water purification plant of Milwaukie City, United States. 9 refs., 6 figs., 4 tabs.

  17. Oxidation of Ce(III) in Foam Decontaminant by Ozone

    International Nuclear Information System (INIS)

    Jung, Chong Hun; Yoon, I. H.; Choi, W. K.; Moon, J. K.; Yang, H. B.; Lee, J. S.

    2016-01-01

    A nanoparticle-based foam decontaminant is composed of a surfactant and nanoparticles for the generation and maintenance of foam, and a chemical decontamination agent made of Ce(IV) dissolved in nitric acid. Ce(IV) will be reduced to Ce(III) through the decontamination process. Oxidizing cerium(III) can be reused as a decontamination agent, Ce(IV). Oxidation treatment technology by ozone uses its strong oxidizing power. It can be regarded as an environmentally friendly process, because ozone cannot be stored and transported like other industrial gases (because it quickly decays into diatomic oxygen) and must therefore be produced on site, and used ozone can decompose immediately. The ozonation treatment of Ce(III) in foam decontaminant containing a surfactant is necessary for the effective regeneration of Ce(III). Thus, the present study was undertaken to determine the optimal conditions for ozonation treatment in the regeneration of Ce(III) into Ce(IV) in the nanoparticle-based foam decontaminant containing surfactant. This study was undertaken to determine the optimal conditions for ozonation treatment in the regeneration of Ce(III) to Ce(IV) in nanoparticle-based foam decontaminant containing a TBS surfactant. The oxidation conversion rate of Ce(III) was increased with an increase in the flow rate of the gas mixture and ozone injection amount. The oxidation time required for the 100% oxidation conversion of Ce(III) to Ce(IV) at a specific ozone injection amount can be predicted from these experimental data

  18. Removal of pharmaceuticals in WWTP effluents by ozone and ...

    African Journals Online (AJOL)

    Ozonation to achieve removal of pharmaceuticals from wastewater effluents, with pH values in the upper and lower regions of the typical range for Swedish wastewater, was investigated. The main aim was to study the effects of varying pH values (6.0 and 8.0), and if small additions of H2O2 prior to ozone treatment could ...

  19. Oxidation of Ce(III) in Foam Decontaminant by Ozone

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Chong Hun; Yoon, I. H.; Choi, W. K.; Moon, J. K.; Yang, H. B. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lee, J. S. [Gachon University, Seongnam (Korea, Republic of)

    2016-10-15

    A nanoparticle-based foam decontaminant is composed of a surfactant and nanoparticles for the generation and maintenance of foam, and a chemical decontamination agent made of Ce(IV) dissolved in nitric acid. Ce(IV) will be reduced to Ce(III) through the decontamination process. Oxidizing cerium(III) can be reused as a decontamination agent, Ce(IV). Oxidation treatment technology by ozone uses its strong oxidizing power. It can be regarded as an environmentally friendly process, because ozone cannot be stored and transported like other industrial gases (because it quickly decays into diatomic oxygen) and must therefore be produced on site, and used ozone can decompose immediately. The ozonation treatment of Ce(III) in foam decontaminant containing a surfactant is necessary for the effective regeneration of Ce(III). Thus, the present study was undertaken to determine the optimal conditions for ozonation treatment in the regeneration of Ce(III) into Ce(IV) in the nanoparticle-based foam decontaminant containing surfactant. This study was undertaken to determine the optimal conditions for ozonation treatment in the regeneration of Ce(III) to Ce(IV) in nanoparticle-based foam decontaminant containing a TBS surfactant. The oxidation conversion rate of Ce(III) was increased with an increase in the flow rate of the gas mixture and ozone injection amount. The oxidation time required for the 100% oxidation conversion of Ce(III) to Ce(IV) at a specific ozone injection amount can be predicted from these experimental data.

  20. Matching Electron Beams Without Secondary Collimation for Treatment of Extensive Recurrent Chest-Wall Carcinoma

    International Nuclear Information System (INIS)

    Feygelman, Vladimir; Mandelzweig, Yuri; Baral, Ed

    2015-01-01

    Matching electron beams without secondary collimators (applicators) were used for treatment of extensive, recurrent chest-wall carcinoma. Due to the wide penumbra of such beams, the homogeneity of the dose distribution at and around the junction point is clinically acceptable and relatively insensitive to positional errors. Specifically, dose around the junction point is homogeneous to within ±4% as calculated from beam profiles, while the positional error of 1 cm leaves this number essentially unchanged. The experimental isodose distribution in an anthropomorphic phantom supports this conclusion. Two electron beams with wide penumbra were used to cover the desired treatment area with satisfactory dose homogeneity. The technique is relatively simple yet clinically useful and can be considered a viable alternative for treatment of extensive chest-wall disease. The steps are suggested to make this technique more universal.

  1. Ozone-induced changes in the chloroplast structure of conifer needles, and their use in ozone diagnostics

    International Nuclear Information System (INIS)

    Kivimaeenpaeae, M.; Sellden, G.; Sutinen, S.

    2005-01-01

    Ozone induces characteristic symptoms in the chloroplasts of the needles of several coniferous species. Chloroplasts are (1) reduced in size and (2) the stroma is electron dense. Moreover (3) these chloroplast alterations are more pronounced in the outer mesophyll cell layers and in the upper side of the needle compared to the inner layers and lower side. The syndrome, including the three symptoms (1)-(3), is found in the green needles of Scots pine and Norway spruce not only in the experimental fumigations, but also in mature trees in the field, and has potential for diagnosis of ozone stress. For sound ozone diagnostics all three symptoms must be present in the samples studied. The symptoms in relation to needle anatomy and physiology is discussed, and recommendations for sampling and analysis are given. - Ozone-induced alterations in chloroplast structure of conifer needles are reviewed, and recommendations for field monitoring given

  2. SU-E-T-447: Electronic Brachytherapy (EBT) Treatment of Cervical Cancer - First Clinical Experience

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D; Johnson, M; Thompson, J; Ahmad, S [University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma (United States); Chan, L; Hausen, H [Xoft Inc., San Jose, CA (United States)

    2014-06-01

    Purpose: To study the first trial patient in which an electronic brachytherapy (EBT) x-ray source is utilized for treatment of cervical cancer. Methods: During patient treatment, a miniaturized x-ray source was used in combination with a customized titanium tandem and ovoid applicator set. The semi-specialized source was modeled with formalisms outlined by AAMP Task Group 43. Multiple models were used to compensate for variable attenuation conditions as a function of source positions. Varian Brachyvision treatment planning software was utilized on CT data sets for dose calculations prior to treatment delivery. The dose was prescribed to “point A” as defined by American Brachytherapy society. Additional treatments plans were created from those clinically utilized in patient care and were recalculated for an existing Ir-192 source model. Dose volume histograms (DVH) and point dose calculations were compared between the modalities for the clinical condition present in patients treated with EBT. Results: Clinical treatment times, though longer than those typically experienced by Ir-192 users, were manageable. Instantaneous dose rates at personal positions within the treatment vault were lower than those measured during intra operative radiation therapy and breast EBT treatments. Due to lower average photon energy in EBT, dose gradients within the treatment plans were as expected steeper than those observed in Ir-192 based brachytherapy. DVH comparisons between Ir-192 and EBT treatments showed an expected decrease in the integral dose to normal tissues of interest for EBT. In comparing plans created for EBT delivery with those calculated for Ir-192, average dose values for EBT were more than 4%, 11%, and 9% lower at predefined bladder, rectum and “point B” positions, respectively. Conclusion: For the first time, we have demonstrated that the utilizing electronic brachytherapy system for tandem and ovoid based treatment of cancer of the cervix is feasible, and

  3. The determination and fate of disinfection by-products from ozonation of polluted raw water

    International Nuclear Information System (INIS)

    Huang, W.-J.; Fang, G.-C.; Wang, C.-C.

    2005-01-01

    The major disinfection by-products (DBPs) resulting from ozone treatment of polluted surface water were investigated. By-products of either health concern or which may contribute to biological instability of treated drinking water were investigated. The major DBPs were analyzed in two fractions: carbonyl compounds and brominated organic compounds. The natural organic matter (NOM) was also isolated and fractionated from polluted water for subsequent ozonation and DBPs identification under conditions of typical drinking treatment. The main identified carbonyl compounds were low molecular weight carboxylic acids, benzoic compounds, aliphatic aldehydes and odorous aldehydes, respectively. Brominated organics were also found in ozonated water, including bromoform (CHBr 3 ), monobromoacetic acid (MBAA), dibromoacetic acid (DBAA), 2,4-dibromophenol (2,4-DBP) and dibromoacetonitrile (DBAN), respectively. It was also found that the characteristic of organic precursors have significant influences on brominated organic by-products formation. Humic acid demonstrated the highest CHBr 3 , DBAA and 2,4-DBP formations, whereas hydrophilic neutral produced less CHBr 3 and 2,4-DBP than the rest of the organic fractions but produced the highest amount of DBAN. In addition to the other target compounds, a total of 59 different organic compounds were detected by means of gas chromatograph/high-resolution electron-impact mass spectrometry (GC/EI-MS) detection and tentatively identified using mass spectral library searching, mainly aromatics, acids/esters, alcohols, aldehydes, phthalates and amines/amino acids were analyzed. The percentage of elimination or formation levels reached during ozonation is also discussed in this study

  4. Optimization of Industrial Ozone Generation with Pulsed Power

    Science.gov (United States)

    Lopez, Jose; Guerrero, Daniel; Freilich, Alfred; Ramoino, Luca; Seton Hall University Team; Degremont Technologies-Ozonia Team

    2013-09-01

    Ozone (O3) is widely used for applications ranging from various industrial chemical synthesis processes to large-scale water treatment. The consequent surge in world-wide demand has brought about the requirement for ozone generation at the rate of several hundreds grams per kilowatt hour (g/kWh). For many years, ozone has been generated by means of dielectric barrier discharges (DBD), where a high-energy electric field between two electrodes separated by a dielectric and gap containing pure oxygen or air produce various microplasmas. The resultant microplasmas provide sufficient energy to dissociate the oxygen molecules while allowing the proper energetics channels for the formation of ozone. This presentation will review the current power schemes used for large-scale ozone generation and explore the use of high-voltage nanosecond pulses with reduced electric fields. The created microplasmas in a high reduced electric field are expected to be more efficient for ozone generation. This is confirmed with the current results of this work which observed that the efficiency of ozone generation increases by over eight time when the rise time and pulse duration are shortened. Department of Physics, South Orange, NJ, USA.

  5. The effect of chronic ozone exposure on the activation of endoplasmic reticulum stress and apoptosis in rat hippocampus

    Directory of Open Access Journals (Sweden)

    Erika Rodríguez-Martínez

    2016-10-01

    Full Text Available The chronic exposure to low doses of ozone, like in environmental pollution, leads to a state of oxidative stress, which has been proposed to contribute to neurodegenerative disorders, including Alzheimer's disease. It induces an increase of calcium in the endoplasmic reticulum (ER, which produces ER stress. On the other hand, different studies show that, in diseases such as Alzheimer’s, there exist disturbances in protein folding where ER plays an important role. The objective of this study was to evaluate the state of chronic oxidative stress on ER stress and its relationship with apoptotic death in the hippocampus of rats exposed to low doses of ozone. We used 108 male Wistar rats randomly divided into five groups. The groups received one of the following treatments: 1 Control (air, 2 Ozone (O3 7 days, 3 O3 15 days, 4 O3 30 days, 5 O3 60 days, and 6 O3 90 days. Two hours after each treatment, the animals were sacrificed and the hippocampus was extracted. Afterwards, the tissue was processed for western blot and immunohistochemistry using the following antibodies: ATF6, GRP8 and caspase 12. It was also performed TUNEL assay and electronic microscopy. Our results show an increase in ATF6, GRP78 and caspase 12 as well as ER ultrastructural alterations and an increase of TUNEL positive cells after 60 and 90 days of exposure to ozone. With the obtained results, we can conclude that oxidative stress induced by chronic exposure to low doses of ozone leads to ER stress. ER stress activates ATF6 inducing the increase of GRP78 in the cytoplasm, which leads to the increase in the nuclear translocation of ATF6. Finally, the translocation creates a vicious cycle that, together with the activation of the cascade for apoptotic cell death, contributes to the maintenance of ER stress. These events potentially contribute in the neurodegeneration processes in diseases like Alzheimer’s Disease.

  6. Generation of ozone and safety aspects in an accelerator facility of BARC

    International Nuclear Information System (INIS)

    Dubey, Praveen; Sawatkar, Aparna R.; Sathe, Arun P.; Soundararajan, S.; Sarma, K.S.S.

    2009-01-01

    Industrial electron beam accelerators up to 10 MeV are commonly employed for different applications. During normal operation of an accelerator, the principal hazard is the high radiation level produced. Experiments and applications in which the electron beam is used to irradiate materials outside the accelerator vacuum system are associated with problems such as radiation damage and production of considerable quantities of ozone. The possible generation of ozone during the operation of an electron beam accelerator is of special interest due to reactivity, corrosivity and the toxic characteristics of ozone. Industrial hygiene surveys were conducted to estimate the airborne concentration of ozone during operations of the electron beam accelerator (Type: ILU-6; 2 MeV; 20 KW) at varied operating parameters. The ozone concentration in the accelerator room was measured at different powers of the accelerator and the ozone decay pattern was also observed after beam shut down. Ozone in the accelerator room was measured by different methods such as colorimetry using neutral buffered potassium iodide, chemiluminescence method using ethylene and by using electrochemical sensor. An air velocity meter was used to measure the linear air velocity across the exhaust grills and the number of air changes available in the accelerator room was calculated. Necessary control measures were suggested to keep the occupational exposure of the personnel to ozone concentrations well within the Threshold Limit Values. (author)

  7. Proceedings of the FNCA 2004 workshop on application of electron accelerator. EB treatment of flue gases

    International Nuclear Information System (INIS)

    Yoshii, Fumio; Kume, Tamikazu

    2005-06-01

    'Forum for Nuclear Cooperation in Asia (FNCA) Workshop on Application of Electron Accelerator' was sponsored by the Ministry of Education, Culture, Sports, Science and Technology (MEXT). The 2004 workshop was jointly organized by China Atomic Energy Authority (CAEA), Institute of Modern Physics/Chinese Academy of Sciences(IMP-CAS) and Japan Atomic Energy Research Institute (JAERI). It was held at Prime Hotel, Beijing, China from 6 to 10 September 2004. The Workshop was attended by 28 experts on application of electron accelerator from each of the participating countries, i.e., China, Indonesia, Korea, Malaysia, The Philippines, Thailand and Vietnam, and 10 participants from Japan. On the first day, a National Executive Management Seminar on Application of Electron Accelerator was held and attended by 67 participants. Total of 20 papers including Seminar lectures, invited papers on flue gas treatment by electron beam, and country reports on EB irradiation system were presented. The major areas of interest of FNCA member states for cooperation were identified for application of low energy electron accelerator as liquid (natural polymer, wastewater), solid (hydrogel, thin film) and gases (flue gas). Based on the proposal from the participating countries, discussions were carried out to re-formulate the work plan of the project for three years until FY 2005. It was agreed the FNCA 2005 workshop on EB treatment of wastewater will be held in Korea. All manuscripts submitted by every speaker were included in the proceedings. The 20 of the presented papers are indexed individually. (J.P.N.)

  8. A study on radiation treatment of wastewater using an electron accelerator

    International Nuclear Information System (INIS)

    Hashimoto, Shoji

    1982-02-01

    A study on radiation oxidation treatment of refractory or toxic wastewater using an electron accelerator was carried out from the viewpoint of reaction engineering. For the process using electron beams, oxygen supply to the penetration range of electron (reaction zone) where the dose rate is extremely high, is significantly important. A concentric dual-tube-type bubbling column reactor was shown to be most suitable to maintain the dissolved oxygen at a high concentration. Rate expressions of pollutant reduction and oxygen consumption in the reactor were derived. The efficiency of active species utilization for oxidation, phi, was defined and shown to be an important design parameter. A new wastewater treatment system (Electron Accelerator-Dual tube Bubbling Reactor system) was proposed, and successfully demonstrated for the treatment of wastewater involving dyes and phenol. The dissolved oxygen was maintained at a high concentration by using this type of reactor for the high dose rate irradiation. phi was obtained as a function of dissolved oxygen concentration for the dye solution and was also obtained as functions of the oxygen concentration and dose rate for the phenol solution. By these experimental results, the effectiveness of EA-DBR system was proved. (author)

  9. Oxidation kinetics of hazelnut oil treated with ozone

    Directory of Open Access Journals (Sweden)

    H. Uzun

    2018-01-01

    Full Text Available The present study investigates the oxidation kinetics of hazelnut oil ozonated in different treatment periods (1, 5, 60 and 180 min. The kinetic rate constant (k was taken as the inverse of oxidation onset time (To observing a linear relationship from the plot of lnTo to isothermal temperatures (373, 383, 393, and 403 K carried out at differential scanning calorimetry. Kinetic parameters, activation energy (Ea, activation enthalpy (ΔH‡ and entropy (ΔS‡ were calculated based on the Arrhenius equation and activated complex theory. k values showed an exponential rise with the increase of ozone treatment time. The increase in k correlated well with the increase in the peroxide and free fatty acid values of all samples. Ea and ∆H‡ of the ozone treated oils showed a reducing trend and reflected an increased oxidation sensitivity after ozone treatment. Consistently, an increase in ∆S‡ indicated a faster oxidation reaction with an increase in ozone exposure time. However, no significant difference was observed in k, Ea, ΔH‡, ΔS‡ (p < 0.05 as a function of storage period, after the hazelnut oil was treated with ozone for 1 min.

  10. Oxidation kinetics of hazelnut oil treated with ozone

    International Nuclear Information System (INIS)

    Uzun, H.; Ibanoglu, E.

    2017-01-01

    The present study investigates the oxidation kinetics of hazelnut oil ozonated in different treatment periods (1, 5, 60 and 180 min). The kinetic rate constant (k) was taken as the inverse of oxidation onset time (To) observing a linear relationship from the plot of ln To to isothermal temperatures (373, 383, 393, and 403 K) carried out at differential scanning calorimetry. Kinetic parameters, activation energy (Ea), activation enthalpy (ΔH‡) and entropy (ΔS‡) were calculated based on the Arrhenius equation and activated complex theory. k values showed an exponential rise with the increase of ozone treatment time. The increase in k correlated well with the increase in the peroxide and free fatty acid values of all samples. Ea and ΔH‡ of the ozone treated oils showed a reducing trend and reflected an increased oxidation sensitivity after ozone treatment. Consistently, an increase in ΔS‡ indicated a faster oxidation reaction with an increase in ozone exposure time. However, no significant difference was observed in k, Ea, ΔH‡, ΔS‡ (p < 0.05) as a function of storage period, after the hazelnut oil was treated with ozone for 1 min. [es

  11. Time-dependent theoretical treatments of the dynamics of electrons and nuclei in molecular systems

    International Nuclear Information System (INIS)

    Deumens, E.; Diz, A.; Longo, R.; Oehrn, Y.

    1994-01-01

    An overview is presented of methods for time-dependent treatments of molecules as systems of electrons and nuclei. The theoretical details of these methods are reviewed and contrasted in the light of a recently developed time-dependent method called electron-nuclear dynamics. Electron-nuclear dynamics (END) is a formulation of the complete dynamics of electrons and nuclei of a molecular system that eliminates the necessity of constructing potential-energy surfaces. Because of its general formulation, it encompasses many aspects found in other formulations and can serve as a didactic device for clarifying many of the principles and approximations relevant in time-dependent treatments of molecular systems. The END equations are derived from the time-dependent variational principle applied to a chosen family of efficiently parametrized approximate state vectors. A detailed analysis of the END equations is given for the case of a single-determinantal state for the electrons and a classical treatment of the nuclei. The approach leads to a simple formulation of the fully nonlinear time-dependent Hartree-Fock theory including nuclear dynamics. The nonlinear END equations with the ab initio Coulomb Hamiltonian have been implemented at this level of theory in a computer program, ENDyne, and have been shown feasible for the study of small molecular systems. Implementation of the Austin Model 1 semiempirical Hamiltonian is discussed as a route to large molecular systems. The linearized END equations at this level of theory are shown to lead to the random-phase approximation for the coupled system of electrons and nuclei. The qualitative features of the general nonlinear solution are analyzed using the results of the linearized equations as a first approximation. Some specific applications of END are presented, and the comparison with experiment and other theoretical approaches is discussed

  12. Determination of Penetration Depth of 800 keV Electron Beam into Coal Fired Power Plant Flue Gas at in a Electron Beam Machine Flue Gas Treatment System

    International Nuclear Information System (INIS)

    Rany Saptaaji

    2008-01-01

    Penetration depth calculation of 800 keV electron beam into flue gas from coal fired power plan is presented in this paper. Electron Beam for Flue Gas Treatment (EB-FGT) is a dry treatment process using electron beam to simultaneously reduce SO 2 and NO x . Flue gas irradiation produces active radicals and then reaction with SO 2 and NO x produces nitrate acid and sulphate acid. Process vessel is needed in this process as reaction container of flue gas with electron beam. The calculation of electron beam penetration depth into flue gas is used to determine the process vessel dimension. The result of calculation of optimum penetration depth of 800 keV electron beam into flue gas is 188.67 cm. (author)

  13. Removal of nalidixic acid and its degradation products by an integrated MBR-ozonation system.

    Science.gov (United States)

    Pollice, A; Laera, G; Cassano, D; Diomede, S; Pinto, A; Lopez, A; Mascolo, G

    2012-02-15

    Chemical-biological degradation of a widely spread antibacterial (nalidixic acid) was successfully obtained by an integrated membrane bioreactor (MBR)-ozonation process. The composition of the treated solution simulated the wastewater from the production of the target pharmaceutical, featuring high salinity and a relevant concentration of sodium acetate. Aim of treatment integration was to exploit the synergistic effects of chemical oxidation and bioprocesses, by adopting the latter to remove most of the COD and the ozonation biodegradable products. Integration was achieved by placing ozonation in the recirculation stream of the bioreactor effluent. The recirculation flow rate was three-fold the MBR feed, and the performance of the integrated system was compared to the standard polishing configuration (single ozonation step after the MBR). Results showed that the introduction of the ozonation step did not cause relevant drawbacks to both biological and filtration processes. nalidixic acid passed undegraded through the MBR and was completely removed in the ozonation step. Complete degradation of most of the detected ozonation products was better achieved with the integrated MBR-ozonation process than using the sequential treatment configuration, i.e. ozone polishing after MBR, given the same ozone dosage. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. [Ozone concentration distribution of urban].

    Science.gov (United States)

    Yin, Yong-quan; Li, Chang-mei; Ma, Gui-xia; Cui, Zhao-jie

    2004-11-01

    The increase of ozone concentration in urban is one of the most important research topics on environmental science. With the increase of nitrogen oxides and hydrogen-carbon compounds which are exhausted from cars, the ozone concentration in urban is obviously increased on sunlight, and threat of photochemistry smog will be possible. Therefore, it is very important to monitor and study the ozone concentration distribution in urban. The frequency-distribution, diurnal variation and monthly variation of ozone concentration were studied on the campus of Shandong University during six months monitoring. The influence of solar radiation and weather conditions on ozone concentration were discussed. The frequency of ozone concentration less than 200 microg/m3 is 96.88%. The ozone concentration has an obvious diurnal variation. The ozone concentration in the afternoon is higher than in the morning and in the evening. The maximum appears in June, when it is the strong solar radiation and high air-temperature. The weather conditions also influence the ozone concentration. The ozone concentration in clear day is higher than in rainy and cloudy day.

  15. Physiological studies on photochemical oxidant injury in rice plants. II. Effect of abscisic acid (ABA) on ozone injury and ethylene production in rice plants

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y.H.; Nakamura, H.; Ota, Y.

    1981-12-01

    In order to determine the effect of ABA on ozone injury to rice plants, ethylene production, rate of chlorophyll retention and ozone-sensitivity of rice plants pretreated with ABA solution were investigated. The experiments were carried out in pots using rice plants at the 7-8 leaf stage. The results obtained are summarized as follows: ethylene production by the leaf blades exposed to ozone increased with the increase in the dosage of ozone; ethylene production was higher in cv. Nihonbare which was more sensitive to ozone than in cv. Tongil; pre-treatment with ABA solution one hour before ozone treatment reduced ethylene production by the leaf blades exposed to ozone; and the rate of chlorophyll retention decreased following injury, but increased remarkably by the pre-treatment with ABA solution. In conclusion, it could be demonstrated that ozone injury of rice plants can be reduced by the pre-treatment with ABA solution. 28 references, 5 figures, 1 table.

  16. Electronic problem-solving treatment: description and pilot study of an interactive media treatment for depression.

    Science.gov (United States)

    Cartreine, James Albert; Locke, Steven E; Buckey, Jay C; Sandoval, Luis; Hegel, Mark T

    2012-09-25

    Computer-automated depression interventions rely heavily on users reading text to receive the intervention. However, text-delivered interventions place a burden on persons with depression and convey only verbal content. The primary aim of this project was to develop a computer-automated treatment for depression that is delivered via interactive media technology. By using branching video and audio, the program simulates the experience of being in therapy with a master clinician who provides six sessions of problem-solving therapy. A secondary objective was to conduct a pilot study of the program's usability, acceptability, and credibility, and to obtain an initial estimate of its efficacy. The program was produced in a professional multimedia production facility and incorporates video, audio, graphics, animation, and text. Failure analyses of patient data are conducted across sessions and across problems to identify ways to help the user improve his or her problem solving. A pilot study was conducted with persons who had minor depression. An experimental group (n = 7) used the program while a waitlist control group (n = 7) was provided with no treatment for 6 weeks. All of the experimental group participants completed the trial, whereas 1 from the control was lost to follow-up. Experimental group participants rated the program high on usability, acceptability, and credibility. The study was not powered to detect clinical improvement, although these pilot data are encouraging. Although the study was not powered to detect treatment effects, participants did find the program highly usable, acceptable, and credible. This suggests that the highly interactive and immersive nature of the program is beneficial. Further clinical trials are warranted. ClinicalTrials.gov NCT00906581; http://clinicaltrials.gov/ct2/show/NCT00906581 (Archived by WebCite at http://www.webcitation.org/6A5Ni5HUp).

  17. Bolus electron conformal therapy for the treatment of recurrent inflammatory breast cancer: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Michelle M., E-mail: mmkim@mdanderson.org [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States); Kudchadker, Rajat J.; Kanke, James E.; Zhang, Sean; Perkins, George H. [Department of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX (United States)

    2012-07-01

    The treatment of locoregionally recurrent breast cancer in patients who have previously undergone radiation therapy is challenging. Special techniques are often required that both eradicate the disease and minimize the risks of retreatment. We report the case of a patient with an early-stage left breast cancer who developed inflammatory-type recurrence requiring re-irradiation of the chest wall using bolus electron conformal therapy with image-guided treatment delivery. The patient was a 51-year-old woman who had undergone lumpectomy, axillary lymph node dissection, and adjuvant whole-breast radiation therapy for a stage I left breast cancer in June 1998. In March 2009, she presented at our institution with biopsy-proven recurrent inflammatory carcinoma and was aggressively treated with multi-agent chemotherapy followed by mastectomy that left a positive surgical margin. Given the patient's prior irradiation and irregular chest wall anatomy, bolus electron conformal therapy was used to treat her chest wall and draining lymphatics while sparing the underlying soft tissue. The patient still had no evidence of disease 21 months after treatment. Our results indicate that bolus electron conformal therapy is an accessible, effective radiation treatment approach for recurrent breast cancer in patients with irregular chest wall anatomy as a result of surgery. This approach may complement standard techniques used to reduce locoregional recurrence in the postmastectomy setting.

  18. Comparative study of ozonized olive oil and ozonized sunflower oil

    OpenAIRE

    Díaz,Maritza F.; Hernández,Rebeca; Martínez,Goitybell; Vidal,Genny; Gómez,Magali; Fernández,Harold; Garcés,Rafael

    2006-01-01

    In this study the ozonized olive and sunflower oils are chemical and microbiologically compared. These oils were introduced into a reactor with bubbling ozone gas in a water bath at room temperature until they were solidified. The peroxide, acidity and iodine values along with antimicrobial activity were determined. Ozonization effects on the fatty acid composition of these oils were analyzed using Gas-Liquid Chromatographic Technique. An increase in peroxidation and acidity values was observ...

  19. Yield of Ozone, Nitrite Nitrogen and Hydrogen Peroxide Versus Discharge Parameter Using APPJ Under Water

    International Nuclear Information System (INIS)

    Chen Bingyan; Wen Wen; Zhu Changping; Wang Yuan; Gao Ying; Fei Juntao; He Xiang; Yin Cheng; Jiang Yongfeng; Chen Longwei

    2016-01-01

    Discharge plasma in and in contact with water can be accompanied with ultraviolet radiation and electron impact, thus can generate hydroxyl radicals, ozone, nitrite nitrogen and hydrogen peroxide. In this paper, a non-equilibrium plasma processing system was established by means of an atmospheric pressure plasma jet immersed in water. The hydroxyl intensities and discharge energy waveforms were tested. The results show that the positive and negative discharge energy peaks were asymmetric, where the positive discharge energy peak was greater than the negative one. Meanwhile, the yield of ozone and nitrite nitrogen was enhanced with the increase of both the treatment time and the discharge energy. Moreover, the pH value of treated water was reduced rapidly and maintained at a lower level. The residual concentration of hydrogen peroxide in APPJ treated water was kept at a low level. Additionally, both the efficiency energy ratio of the yield of ozone and nitrite nitrogen and that of the removal of p-nitrophenol increased as a function of discharge energy and discharge voltage. The experimental results were fully analyzed and the chemical reaction equations and the physical processes of discharges in water were given. (paper)

  20. Investigation of In-Package Ozonation: The Effectiveness of Ozone to Inactive Salmonella enteritidis on Raw, Shell Eggs

    Directory of Open Access Journals (Sweden)

    Austin Donner

    2011-01-01

    Full Text Available Food production, handling, and distribution practices pose a constant threat to the quality and safety of food products. The objective of this research is to evaluate an innovative in-package ozonation process to reduce Salmonella enteritidis on raw, shell eggs. Previous research has shown that in-package ozonation eliminates contaminants from outside sources, reduces pathogens, and extends shelf life. In this study, raw, shell eggs were inoculated with Salmonella enteritidis and exposed to ozonation treatment. Microbial recoveries were then tested to determine bacterial reductions. Measurements included: relative humidity (34 percent at 5oC, surface temperatures (oC, ozone concentrations, bacterial reductions of Salmonella enteritidis, and quality assessment of eggs (Haugh Unit [HU], color, pH, and weight. After a 24-hour storage period, all treated samples indicated 3 log10 reductions on average (previous research has achieved up to 6log10. These results show effective in-package ozonation treatment reducing Salmonella enteritidis on raw, shell eggs without significant effect on measured egg quality over time. Benefits of in-package ozonation include no heating, low power requirements (less or equal to 50 Watts, short treatment time (seconds to minutes, and adaptability into existing processes. Given its ability to ensure the safety and longevity of food products, this technology has great potential for utilization in the food processing industry.

  1. Heterogeneous catalytic ozonation of ciprofloxacin in water with carbon nanotube supported manganese oxides as catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Sui, Minghao, E-mail: suiminghao.sui@gmail.com [State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China); Xing, Sichu; Sheng, Li; Huang, Shuhang; Guo, Hongguang [State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer Ciprofloxacin in water was degraded by heterogeneous catalytic ozonation. Black-Right-Pointing-Pointer MnOx were supported on MWCNTs to serve as catalyst for ozonation. Black-Right-Pointing-Pointer MnOx/MWCNT exhibited highly catalytic activity on ozonation of ciprofloxacin in water. Black-Right-Pointing-Pointer MnOx/MWCNT resulted in effective antibacterial activity inhibition on ciprofloxacin. Black-Right-Pointing-Pointer MnOx/MWCNT promoted the generation of hydroxyl radicals. - Abstract: Carbon nanotube-supported manganese oxides (MnOx/MWCNT) were used as catalysts to assist ozone in degrading ciprofloxacin in water. Manganese oxides were successfully loaded on multi-walled carbon nanotube surfaces by simply impregnating the carbon nanotube with permanganate solution. The catalytic activities of MnOx/MWCNT in ciprofloxacin ozonation, including degradation, mineralization effectiveness, and antibacterial activity change, were investigated. The presence of MnOx/MWCNT significantly elevated the degradation and mineralization efficiency of ozone on ciprofloxacin. The microbiological assay with a reference Escherichia coli strain indicated that ozonation with MnOx/MWCNT results in more effective antibacterial activity inhibition of ciprofloxacin than that in ozonation alone. The effects of catalyst dose, initial ciprofloxacin concentration, and initial pH conditions on ciprofloxacin ozonation with MnOx/MWCNT were surveyed. Electron spin resonance trapping was applied to assess the role of MnOx/MWCNT in generating hydroxyl radicals (HO{center_dot}) during ozonation. Stronger 5,5-dimethyl-1-pyrroline-N-oxide-OH signals were observed in the ozonation with MnOx/MWCNT compared with those in ozonation alone, indicating that MnOx/MWCNT promoted the generation of hydroxyl radicals. The degradation of ciprofloxacin was studied in drinking water and wastewater process samples to gauge the potential effects of water background matrix on

  2. Structure and properties of the tool steel after electron beam treatment and following tempering

    International Nuclear Information System (INIS)

    Kozyr', I.G.; Borodin, R.V.; Voropaev, A.V.; Potapov, V.G.

    1998-01-01

    The possibility of changing the surface structure of chromium tool steel has been considered. The given properties were reached through the surface remelting by electron beam with following tempering of strengthened layer. The found distinguished zones with different structure and properties are formed as the result of this treatment. It is shown that for hipereutectoid steel the thermal furnace annealing at 300 deg C is necessary for strengthened surface layer forming after electron beam remelting. The same result can be had by means of short-term heating with electronic beam up to higher temperatures, but is not higher A 1 . The evaluation of temperature fields was carried out by numerical solution of nonstationary heat conductivity equation

  3. Advanced Oxidation Treatment of Drinking Water and Wastewater Using High-energy Electron Beam Irradiation

    Directory of Open Access Journals (Sweden)

    Abbas Behjat

    2007-03-01

    Full Text Available Application of electron beam as a strong oxidation method for disinfection of drinking water and wastewater has been investigated. Drinking water samples were prepared from wells in rock zones in Yazd Province. Wastewater samples were collected from Yazd Wastewater Treatment Plant. Samples were irradiated by 10 MeV electron beam accelerator at Yazd Radiation Processing Center. The irradiation dose range varied from 0.5-5 kGy. Biological parameters and microbial agents such as aerobic mesophiles and coliforms including E. coli count before and after irradiation versus irradiation dose were obtained using MPN method. The data obtained from irradiated water and wastewater were compared with un-irradiated (control samples. The results showed a removal of 90% of all microorganisms at irradiation doses below 5 kGy, suggesting electron beam irradiation as an effective method for disinfection of wastewater.

  4. Health Effects of Ozone and Particle Pollution

    Science.gov (United States)

    ... this page: Health Effects of Ozone and Particle Pollution Two types of air pollution dominate in the ... So what are ozone and particle pollution? Ozone Pollution It may be hard to imagine that pollution ...

  5. Reinterpretation of ozone data from Base Roi Baudouin

    Science.gov (United States)

    Kelder, H.; Muller, C.

    1994-01-01

    The ozone Dobson measurements obtained in Antarctica at the Belgian 'Base Roi Baudouin' (70 deg 26 min S, 24 deg 19 min E) in 1965 and 1966 were retrieved from the KNMI (Royal Netherlands Meteorological Institute) archives in De Bilt. Despite excellent treatment at the time by the meteorologists in charge at the KNMI (Wisse and Meerburg, 1969), a study of the original observers notes was made in order to check possible seasonal ozone phenomena. No systematic anomaly in the first analysis was found; meteorological data from the site together with Brewer-Mast ozone soundings concur that the conditions did not correspond either in 1965 nor 1966 to the current ozone hole (Farman et al., 1985) situation, however, the data yields excellent correlation with stratospheric temperature and shows in 1966 a clear November maximum in opposition to an October value around 344 Dobson units.

  6. Present status on the use of electron accelerator for wastewater treatment in Korea

    International Nuclear Information System (INIS)

    Lee, Myun Joo; Han, Bum Soo; Choi, Jang Seung; Kang, Ho

    2006-01-01

    In the part 1, four major irradiation R and D works studied in field of wastewater treatment in Korea were introduced. Disinfection of total coli-forms in unchlorinated secondary effluent, removal of color in dyeing wastewater and feasibility test to control algal bloom used the electron beam as a radiation source. Treatment of groundwater polluted by TCE and PCE used gamma rays as a radiation source. Backgrounds and experimental results on each research topic were introduced. In the part 2, national on-going projects related to wastewater treatment using irradiation technology in Korea were introduced. With regarding these projects, EB treatment plant for textile dyeing wastewater was described based on the construction and evaluation of ecological stability. (author)

  7. Laboratory scale electron beam system for treatment of flue gases from diesel combustion

    International Nuclear Information System (INIS)

    Siti Aiasah Hashim; Khairul Zaman Mohd Dahlan; Khomsaton Abu Bakar; Ayub Muhammad

    2004-01-01

    Laboratory scale test rig to treat simulated flue gas using electron beam technology was installed at the Alurtron EB-Irradiation Center, MINT. The experiment test rig was proposed as a result of feasibility studies conducted jointly by IAEA, MINT and TNB Research in 1997. The test rig system consists of several components, among other, diesel generator sets, pipe ducts, spray cooler, ammonia dosage system, irradiation vessel, bag filter and gas analyzers. The installation was completed and commissioned in October 2001. results from the commissioning test runs and subsequent experimental work showed that the efficiency of flue gas treatment is high. It was proven that electron beam technology might be applied in the treatment of air pollutants. This paper describes the design and work function of the individual major components as well as the full system function. Results from the initial experimental works are also presented. (Author)

  8. On the treatment of light-ion electronic stopping in dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Schiwietz, G. (Hahn-Meitner-Inst. Berlin GmbH, Div., FD (Germany)); Grande, P.L. (Hahn-Meitner-Inst. Berlin GmbH, Div., FD (Germany))

    1994-05-01

    A review is given on single-electron mechanisms and the corresponding theoretical approaches describing the electronic energy-transfer processes of light ions in gases and solids. Special emphasis is given to a discussion on the connection between exact Bloch-wave treatments and free-atom approximations. In the case of solids, perturbation theory is applied to the stopping of low-energy ions in the alkaline metals Li and Na. These calculations include Bloch wavefunctions of the Wigner-Seitz type obtained from a Hartree-Fock-Slater calculation and allow for a prediction of the mean energy loss under channeling conditions. Results of the most widely used local-density approximation are compared to data of our more complete perturbative treatment. Comparison is also made with recent LCAO calculations. (orig.)

  9. Electron beam flue gas treatment. Research cooperation among JAERI, IAEA and INCT

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The research co-operation is conducted among Japan Atomic Energy Research Institute (JAERI), International Atomic Energy Agency (IAEA) and Institute of Nuclear Chemistry and Technology in Poland (INCT) on Electron Beam Flue Gas Treatment from January 1993 to March 1997. The first phase of the cooperation was carried out for 3 years from January 1993 to March 1995. This cooperation was performed through information exchange meetings (Coordination Meetings), held in Takasaki and Warsaw, and experiments and discussions by exchange scientists. Many useful results were obtained on electron beam treatment of flue gas from coal-combustion heat generation plant in Kaweczyn within the frame work of the research co-operation. This report includes the main results of the tripartite research cooperation. (author)

  10. Protecting the ozone layer.

    Science.gov (United States)

    Munasinghe, M; King, K

    1992-06-01

    Stratospheric ozone layer depletion has been recognized as a problem by the Vienna Convention for the Protection of the Ozone Layer and the 1987 Montreal Protocol (MP). The ozone layer shields the earth from harmful ultraviolet radiation (UV-B), which is more pronounced at the poles and around the equator. Industrialized countries have contributed significantly to the problem by releasing chlorofluorocarbons (CFCs) and halons into the atmosphere. The effect of these chemicals, which were known for their inertness, nonflammability, and nontoxicity, was discovered in 1874. Action to deal with the effects of CFCs and halons was initiated in 1985 in a 49-nation UN meeting. 21 nations signed a protocol limiting ozone depleting substances (ODS): CFCs and halons. Schedules were set based on each country's use in 1986; the target phaseout was set for the year 2000. The MP restricts trade in ODSs and weights the impact of substances to reflect the extent of damage; i.e., halons are 10 times more damaging than CFCs. ODS requirements for developing countries were eased to accommodate scarce resources and the small fraction of ODS emissions. An Interim Multilateral Fund under the Montreal Protocol (IMFMP) was established to provide loans to finance the costs to developing countries in meeting global environmental requirements. The IMFMP is administered by the World Bank, the UN Environmental Program, and the UN Development Program. Financing is available to eligible countries who use .3 kg of ODS/person/year. Rapid phaseout in developed countries has occurred due to strong support from industry and a lower than expected cost. Although there are clear advantages to rapid phaseout, there were no incentives included in the MP for rapid phaseout. Some of the difficulties occur because the schedules set minimum targets at the lowest possible cost. Also, costs cannot be minimized by a country-specific and ODS-specific process. The ways to improve implementation in scheduling and

  11. Development of biological treatment known as SBR process for supporting radiation treatment of industrial wastewater using electron beam

    International Nuclear Information System (INIS)

    Khomsaton Abu Bakar; Siti Aishah Hashim; Zulkafli Ghazali; Khairul Zaman Dahlan; Ismail Yaziz

    2005-01-01

    Electron beam irradiation of wastewater is capable of degrading stable non-biodegradable compound. However it requires high dose and in turn increase the cost of operation. A combination of irradiation and biological treatment is expected to overcome this problem. In this study, the treatment system will use a biological process known as Sequencing Batch Reactor (SBR). The SBR will be developed in a series and each series consist of reaction tank and clarifier tank. Filling and reaction step will occur in reaction tank while settling, decanting and idling step will ensue in the clarifier tank. The process is designed as such to enable rapid and simultaneous analysis on treated sample in order to achieve reliable results. (Author)

  12. Improving the properties of stainless steel electron-beam welds by laser treatment

    International Nuclear Information System (INIS)

    Wu Xueyi; Zhou Changchi

    1991-10-01

    For improving the properties of corrosion resistance of stainless steel, which is widely used in nuclear engineering, the technological test on rapid fusing and setting formed by using laser treatment in electron-beam welds on stainless steel was investigated and the analytical results of welding structure and properties were reported. The experimental results show that after laser treatment more finegrained structure in the surface of the welding centreline and welding heat-affected zone was observed. Segregation of chemical composition was reduced. Plasticity and corrosion resistance in the welding zone was increased. Intergranular corrosion of heat-affected zone was improved

  13. Mixed boson-fermion description of correlated electrons: Fluctuation corrections in the symmetric treatment

    International Nuclear Information System (INIS)

    Vicente Alvarez, J.J.; Balseiro, C.A.; Ceccatto, H.A.

    1995-07-01

    We consider the introduction of fluctuation corrections to saddle- point results in the symmetric treatment of a mixed pseudofermion-boson representation of correlated electrons. In our calculations we avoid the complications of working in the discrete imaginary-time formulation of the functional integral, a procedure recently advocated in the literature as mandatory for this problem. For a simple two-site model our approach leads to approximate results in remarkable agreement with the exact ones, and without the spurious nonanalyticities of other similar treatments. (author). 14 refs, 2 figs

  14. Chromium Waste Treatment from Leather Manufacture Using Electron Beam Radiation Technic

    International Nuclear Information System (INIS)

    Didiek Herhady, R.; Sukarsono, R.

    2007-01-01

    Leather manufacture chromium waste treatment using chemical methods have an essential disadvantage, because of the production of the secondary contamination of wastes and separated sediments used by reagents. Therefore, a new technique is needed to solve this problem. The aim of the research to learn the advantages of electron beam radiation for chromium waste treatment. Water radiolysis can be produced by the interaction between electron beam and water or liquid substances. This phenomenon produces many reducing agents and ions that could reduce chromium concentrations in the liquid waste. Ethyl alcohol as a scavenger was added in the waste samples, then the pH of varied from 1, 4, 8 to 12, then were irradiated. Irradiation were done by Electron Beam Machine with dose 15, 25, and 35 kGy. After irradiation, chromium concentration in the samples were analyzed by AAS and UV-vis spectrophotometer. The results had shown that chromium could be reduced by high dose electron beam. The optimum reduction of chromium was achieved at liquid waste pH 8 and irradiation dose 35 kGy. (author)

  15. Novel treatment options for nonmelanoma skin cancer: focus on electronic brachytherapy

    Directory of Open Access Journals (Sweden)

    Kasper ME

    2015-11-01

    Full Text Available Michael E Kasper,1,2 Ahmed A Chaudhary3 1Department of Radiation Oncology, Lynn Cancer Institute at Boca Raton Regional Hospital, Boca Raton, 2Charles E. Schmidt College of Medicine, Florida Atlantic University, FL, 3North Main Radiation Oncology, Warren Alpert School of Medicine, Brown University, RI, USA Abstract: Nonmelanoma skin cancer (NMSC is an increasing health care issue in the United States, significantly affecting quality of life and impacting health care costs. Radiotherapy has a long history in the treatment of NMSC. Shortly after the discovery of X-rays and 226Radium, physicians cured patients with NMSC using these new treatments. Both X-ray therapy and brachytherapy have evolved over the years, ultimately delivering higher cure rates and lower toxicity. Electronic brachytherapy for NMSC is based on the technical and clinical data obtained from radionuclide skin surface brachytherapy and the small skin surface applicators developed over the past 25 years. The purpose of this review is to introduce electronic brachytherapy in the context of the history, data, and utilization of traditional radiotherapy and brachytherapy. Keywords: electronic brachytherapy, superficial radiotherapy, skin surface brachytherapy, electron beam therapy, nonmelanoma skin cancer, basal cell carcinoma, squamous cell carcinoma

  16. Ozone therapy in postgraduate theses in Egypt: systematic review.

    Science.gov (United States)

    AlBedah, Abdullah M N; Khalil, Mohamed K M; Elolemy, Ahmed T; Alrasheid, Mohamed H S; Al Mudaiheem, Abdullah; Elolemy, Tawfik M B

    2013-08-01

    Systematic reviews of the studies published in the major medical data bases have not shown solid support for the use of ozone therapy. Unpublished or grey literature, including postgraduate theses, may solve this controversy. To review the postgraduate theses published in Egypt in order to assess the clinical safety and effectiveness of ozone therapy in specific medical conditions. The databases of the Egyptian Universities' Library Consortium and the databases of each university were searched for postgraduate theses that evaluated ozone therapy as an intervention for any disease or condition in any age group, compared with any or no other intervention and published before September 2010. A total of 28 quasi trials were included. The theses did not report any safety issues in terms of ozone therapy. With respect to its effectiveness, the studies suggested some benefits of ozone in the treatment of dental infection and recovery, musculoskeletal disorders, diabetes mellitus, chronic diseases, and obstetrics and gynaecology. However, the number of studies included was small and they were of limited quality. There is insufficient evidence to recommend the use of ozone in the treatment of dental infections, in facilitating faster dental recovery after extraction or implantation, in diabetes mellitus, musculoskeletal disorders, or obstetrics and gynaecology.

  17. Utilization of high energy electron beam in the treatment of drinking and waste water

    International Nuclear Information System (INIS)

    Oliveira Sampa, M.H. de; Borrely, S.I.; Morita, D.M.

    1991-08-01

    Samples of drinking water and waste water were irradiated using high energy electron beam with doses from 0.37kGy to 100kGy. Preliminary data show the removal of about 100% tri halomethanes (THM) in drinking water (concentration from 2.7 μg/1 to 45μg/1, 90% of the color of the Public Owned Wastewater Treatment Plant effluent and 87% of oil and grease of the cutting fluid waste water. (author)

  18. Use of Ozone to Treat Ileostomy Dermatitis in an Experimental Rat Model.

    Science.gov (United States)

    Biçer, Şenol; Sayar, İlyas; Gürsul, Cebrail; Işık, Arda; Aydın, Merve; Peker, Kemal; Demiryilmaz, İsmail

    2016-03-07

    Dermatitis associated with ileostomy is an important problem that affects many people, especially children. The aim of this study was to investigate the therapeutic effects of ozone on dermatitis due to ileostomy, and to develop an alternative treatment option. A total of 28 rats were divided into 4 groups: control, ileostomy, ozone, and zinc oxide. Ileostomy was performed in all rats except the control group. After a 1-week waiting time, the ozone group was administered ozone therapy and the zinc oxide group was administered zinc oxide cream locally once a day for a total of 7 days. All rats were sacrificed at the end of this period. The efficacy of treatment was examined by biochemical, histopathological, and immunohistochemical parameters. The levels of malondialdehyde (MDA), total glutathione (tGSH), total antioxidant capacity (TAC), and total oxidant status (TOS) were measured from tissue. Vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen (PCNA) were examined immunohistochemically. Dermatitis occurred pathologically in all rats that underwent ileostomy surgery. The lowest dermatitis score was in the ozone treatment group (p<0.05). Ileostomy dermatitis caused increased levels of MDA and TOS. Ozone treatment resulted in reduced MDA and TOS levels, while the levels of tGSH and TAC were increased (p<0.05). Both VEGF and PCNA immunostaining were augmented in the ozone treatment group (p<0.05). Local ozone application may be a good alternative compared to the conventional treatment methods for the prevention of skin lesions that develop after ileostomy.

  19. Growth of Chironomus dilutus larvae exposed to ozone-treated and untreated oil sands process water

    International Nuclear Information System (INIS)

    Anderson, J.; Wiseman, S.; Franz, E.; Jones, P.; Liber, K.; Giesy, J.; Gamal El-Din, M.; Marin, J.

    2010-01-01

    Oil sand processing operations require large quantities of freshwater and produce large volumes of oil sands process water (OSPW) which must be stored on-site. This presentation reviewed various treatment methods for remediating OSPW in order to eliminate downstream toxicity. Naphthenic acids are the most important target fractions for treatment because they are primarily responsible for the acute toxicity of OSPW. Although ozonation has shown promise for reducing OSPW toxicity, the effects of ozonation on aquatic invertebrates remain unknown. This study investigated the effects of exposure to untreated and ozonated OSPW in Chironomus dilutus larvae. OSPW was treated with either a 50 or 80 mg O 3 /L dose of ozonation. The effects of ozonation levels on C. dilutus survival and growth were examined. The study showed that after a 10-day exposure, there were pronounced effects on survival of larvae exposed to ozone-treated or untreated OSPW. Larvae exposed to OSPW were 64-77 percent smaller than their respective controls, but the mean wet mass of organisms exposed to 50 mg O 3 /L ozonated OSPW was not much different from that of the controls. Larvae exposed to 80 mg O 3 /L ozone-treated OSPW were 40 percent smaller than the freshwater controls, and the mean wet mass was also much larger than the untreated OSPW. It was concluded that the toxicity of OSPW to benthic invertebrates may be reduced by ozone treatment.

  20. Enhancing electronic and optoelectronic performances of tungsten diselenide by plasma treatment.

    Science.gov (United States)

    Xie, Yuan; Wu, Enxiu; Hu, Ruixue; Qian, Shuangbei; Feng, Zhihong; Chen, Xuejiao; Zhang, Hao; Xu, Linyan; Hu, Xiaodong; Liu, Jing; Zhang, Daihua

    2018-06-21

    Transition metal dichalcogenides (TMDCs) have recently become spotlighted as nanomaterials for future electronic and optoelectronic devices. In this work, we develop an effective approach to enhance the electronic and optoelectronic performances of WSe2-based devices by N2O plasma treatment. The hole mobility and sheet density increase by 2 and 5 orders of magnitude, reaching 110 cm2 V-1 s-1 and 2.2 × 1012 cm-2, respectively, after the treatment. At the same time, the contact resistance (Rc) between WSe2 and its metal electrode drop by 5 orders of magnitude from 1.0 GΩ μm to 28.4 kΩ μm. The WSe2 photoconductor exhibits superior performance with high responsivity (1.5 × 105 A W-1), short response time (106). We have also built a lateral p-n junction on a single piece of WSe2 flake by selective plasma exposure. The junction reaches an exceedingly high rectifying ratio of 106, an excellent photoresponsivity of 2.49 A W-1 and a fast response of 8 ms. The enhanced optoelectronic performance is attributed to band-engineering through the N2O plasma treatment, which can potentially serve as an effective and versatile approach for device engineering and optimization in a wide range of electronic and optoelectronic devices based on 2D materials.

  1. Ciliary body toxicities of systemic oxcarbazepine and valproic acid treatments: electron microscopic study.

    Science.gov (United States)

    Göktaş, Güleser; Aktaş, Zeynep; Erdoğan, Deniz; Seymen, Cemile Merve; Karaca, Emine Esra; Cansu, Ali; Serdaroğlu, Ayşe; Kaplanoğlu, Gülnur Take

    2015-01-01

    Ciliary body is responsible for humour aqueous production in posterior chamber. Valproic acid (VPA) has been widely used for the treatment of epilepsy and other neuropsychiatric diseases such as bipolar disease and major depression. Oxcarbazepine (OXC) is a new anti-epileptic agent that has been used recently for childhood epilepsies such as VPA. In this study, we aimed to investigate the effects of VPA and OXC treatments used as antiepileptic in ciliary body by electron microscopy. In our study, 40 Wistar rats (21 days old) were divided equally into four groups which were applied saline (group 1), VPA (group 2), OXC (group 3) and VPA + OXC (group 4). The as-prepared ocular tissues were characterized by transmission electron microscopy (TEM) technique in scanning and transmission electron microscopy (SEM-TEM) (Carl Zeiss EVO LS10). The results confirmed that VPA caused dense ciliary body degeneration. Additionally, ciliary body degeneration in group 4 was supposed to be due to VPA treatment. Ciliary body damage and secondary outcomes should be considered in patients with long-term VPA therapy.

  2. Structure-phase states evolution in Al-Si alloy under electron-beam treatment and high-cycle fatigue

    International Nuclear Information System (INIS)

    Konovalov, Sergey; Alsaraeva, Krestina; Gromov, Victor; Semina, Olga; Ivanov, Yurii

    2015-01-01

    By methods of scanning and transmission electron diffraction microscopy the analysis of structure-phase states and defect substructure of silumin subjected to high-intensity electron beam irradiation in various regimes and subsequent fatigue loading up to failure was carried out. It is revealed that the sources of fatigue microcracks are silicon plates of micron and submicron size are not soluble in electron beam processing. The possible reasons of the silumin fatigue life increase under electron-beam treatment are discussed

  3. Investigation of Ozone Yield of Air Fed Ozonizer by High Pressure Homogeneous Dielectric Barrier Discharge

    Science.gov (United States)

    2013-07-01

    around 2 ms and 12 ms in this figure, and during the discharge period, the current was continuous without any pulse . Once a discharge generated in...electron avalanches [10]. Fig. 1. High pressure ozone generator. (a) Top view (b) Side view Fig. 2. Barrier discharge device. Table 1... discharge N. Osawa P1 P, UY. Yoshioka UP2 P, R. Hanaoka P1 P 1 Center for Electric, Optic and Energy applications, Department of Electric and

  4. Monte Carlo based treatment planning for modulated electron beam radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Michael C. [Radiation Physics Division, Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States)]. E-mail: mclee@reyes.stanford.edu; Deng Jun; Li Jinsheng; Jiang, Steve B.; Ma, C.-M. [Radiation Physics Division, Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States)

    2001-08-01

    A Monte Carlo based treatment planning system for modulated electron radiation therapy (MERT) is presented. This new variation of intensity modulated radiation therapy (IMRT) utilizes an electron multileaf collimator (eMLC) to deliver non-uniform intensity maps at several electron energies. In this way, conformal dose distributions are delivered to irregular targets located a few centimetres below the surface while sparing deeper-lying normal anatomy. Planning for MERT begins with Monte Carlo generation of electron beamlets. Electrons are transported with proper in-air scattering and the dose is tallied in the phantom for each beamlet. An optimized beamlet plan may be calculated using inverse-planning methods. Step-and-shoot leaf sequences are generated for the intensity maps and dose distributions recalculated using Monte Carlo simulations. Here, scatter and leakage from the leaves are properly accounted for by transporting electrons through the eMLC geometry. The weights for the segments of the plan are re-optimized with the leaf positions fixed and bremsstrahlung leakage and electron scatter doses included. This optimization gives the final optimized plan. It is shown that a significant portion of the calculation time is spent transporting particles in the leaves. However, this is necessary since optimizing segment weights based on a model in which leaf transport is ignored results in an improperly optimized plan with overdosing of target and critical structures. A method of rapidly calculating the bremsstrahlung contribution is presented and shown to be an efficient solution to this problem. A homogeneous model target and a 2D breast plan are presented. The potential use of this tool in clinical planning is discussed. (author)

  5. Electron/photon matched field technique for treatment of orbital disease

    International Nuclear Information System (INIS)

    Arthur, Douglas W.; Zwicker, Robert D.; Garmon, Pamela W.; Huang, David T.; Schmidt-Ullrich, Rupert K.

    1997-01-01

    Purpose: A number of approaches have been described in the literature for irradiation of malignant and benign diseases of the orbit. Techniques described to date do not deliver a homogeneous dose to the orbital contents while sparing the cornea and lens of excessive dose. This is a result of the geometry encountered in this region and the fact that the target volume, which includes the periorbital and retroorbital tissues but excludes the cornea, anterior chamber, and lens, cannot be readily accommodated by photon beams alone. To improve the dose distribution for these treatments, we have developed a technique that combines a low-energy electron field carefully matched with modified photon fields to achieve acceptable dose coverage and uniformity. Methods and Materials: An anterior electron field and a lateral photon field setup is used to encompass the target volume. Modification of these fields permits accurate matching as well as conformation of the dose distribution to the orbit. A flat-surfaced wax compensator assures uniform electron penetration across the field, and a sunken lead alloy eye block prevents excessive dose to the central structures of the anterior segment. The anterior edge of the photon field is modified by broadening the penumbra using a form of pseudodynamic collimation. Direct measurements using film and ion chamber dosimetry were used to study the characteristics of the fall-off region of the electron field and the penumbra of the photon fields. >From the data collected, the technique for accurate field matching and dose uniformity was generated. Results: The isodose curves produced with this treatment technique demonstrate homogeneous dose coverage of the orbit, including the paralenticular region, and sufficient dose sparing of the anterior segment. The posterior lens accumulates less than 40% of the prescribed dose, and the lateral aspect of the lens receives less than 30%. A dose variation in the match region of ±12% is confronted when

  6. Optimum field size and choice of isodose lines in electron beam treatment

    International Nuclear Information System (INIS)

    Das, Indra J.; Cheng, Chee W.; Healey, Glenn A.

    1995-01-01

    Purpose: A method is provided for the optimum field size and the choice of isodose line for the dose prescription in electron beam therapy. Methods and Materials: Electron beam dose uniformity was defined in terms of target coverage factor (TCF) which is an index of dose coverage of a given treatment volume. The TCF was studied with respect to the field size, the beam energy, and the isodose level for prescription from the measured data for various accelerators. The effect of the TCF on air gap between electron applicator/cone and the surface was investigated. Electron beams from scattering foil and scanned beam units were analyzed for the target coverage. Results: A mathematical method is provided to optimize a field size for target coverage by a given isodose line in terms of TCF which is strongly dependent on the type of accelerator and the design of the collimator. For a given type of collimating system, the TCF does not depend on the type of electron beam production (scattering foil or swept scanned beam). Selection of isodose line for dose prescription is very critical for the value of the TCF and the dose coverage. The TCF is inversely proportional to the isodose value selected for the treatment and nearly linear with field size and beam energy. Air gap between applicator and the surface reduces the dose uniformity. Tertiary collimator moderately improves the lateral coverage for high energy beams. Conclusions: To adequately cover the target volume in electron beam treatment, lateral and depth coverage should be considered. The coverage at depth is strongly dependent on the choice of isodose line or beam normalization. If the dose prescription is at d max (i.e., the 100% isodose line is selected), the choice of beam energy is not critical for depth coverage since d max is nearly independent of energy for smaller fields. The 100% isodose line should not be chosen for treatment because of the significant constriction of this isodose line and inadequate

  7. Ozone exposure of a weed community produces adaptive changes in seed populations of Spergula arvensis.

    Directory of Open Access Journals (Sweden)

    Jennifer B Landesmann

    Full Text Available Tropospheric ozone is one of the major drivers of global change. This stress factor alters plant growth and development. Ozone could act as a selection pressure on species communities composition, but also on population genetic background, thus affecting life history traits. Our objective was to evaluate the consequences of prolonged ozone exposure of a weed community on phenotypic traits of Spergulaarvensis linked to persistence. Specifically, we predicted that the selection pressure exerted by high ozone concentrations as well as the concomitant changes in the weed community would drive population adaptive changes which will be reflected on seed germination, dormancy and longevity. In order to test seed viability and dormancy level, we conducted germination experiments for which we used seeds produced by S. arvensis plants grown within a weed community exposed to three ozone treatments during four years (0, 90 and 120 ppb. We also performed a soil seed bank experiment to test seed longevity with seeds coming from both the four-year ozone exposure experiment and from a short-term treatment conducted at ambient and added ozone concentrations. We found that prolonged ozone exposure produced changes in seed germination, dormancy and longevity, resulting in three S. arvensis populations. Seeds from the 90 ppb ozone selection treatment had the highest level of germination when stored at 75% RH and 25 °C and then scarified. These seeds showed the lowest dormancy level when being subjected to 5 ºC/5% RH and 25 ºC/75% followed by 5% RH storage conditions. Furthermore, ozone exposure increased seed persistence in the soil through a maternal effect. Given that tropospheric ozone is an important pollutant in rural areas, changes in seed traits due to ozone exposure could increase weed persistence in fields, thus affecting weed-crop interactions, which could ultimately reduce crop production.

  8. Ozone exposure of a weed community produces adaptive changes in seed populations of Spergula arvensis.

    Science.gov (United States)

    Landesmann, Jennifer B; Gundel, Pedro E; Martínez-Ghersa, M Alejandra; Ghersa, Claudio M

    2013-01-01

    Tropospheric ozone is one of the major drivers of global change. This stress factor alters plant growth and development. Ozone could act as a selection pressure on species communities composition, but also on population genetic background, thus affecting life history traits. Our objective was to evaluate the consequences of prolonged ozone exposure of a weed community on phenotypic traits of Spergulaarvensis linked to persistence. Specifically, we predicted that the selection pressure exerted by high ozone concentrations as well as the concomitant changes in the weed community would drive population adaptive changes which will be reflected on seed germination, dormancy and longevity. In order to test seed viability and dormancy level, we conducted germination experiments for which we used seeds produced by S. arvensis plants grown within a weed community exposed to three ozone treatments during four years (0, 90 and 120 ppb). We also performed a soil seed bank experiment to test seed longevity with seeds coming from both the four-year ozone exposure experiment and from a short-term treatment conducted at ambient and added ozone concentrations. We found that prolonged ozone exposure produced changes in seed germination, dormancy and longevity, resulting in three S. arvensis populations. Seeds from the 90 ppb ozone selection treatment had the highest level of germination when stored at 75% RH and 25 °C and then scarified. These seeds showed the lowest dormancy level when being subjected to 5 ºC/5% RH and 25 ºC/75% followed by 5% RH storage conditions. Furthermore, ozone exposure increased seed persistence in the soil through a maternal effect. Given that tropospheric ozone is an important pollutant in rural areas, changes in seed traits due to ozone exposure could increase weed persistence in fields, thus affecting weed-crop interactions, which could ultimately reduce crop production.

  9. Theoretical treatment of electron capture and excitation in two-electron system ion-atom, atom-atom collisions at low to intermediate energy

    International Nuclear Information System (INIS)

    Kimura, M.

    1986-01-01

    A review of various theoretical treatments which have been used to study electron-capture and excitation processes in two-electron-system ion-atom, atom-atom collisions at low to intermediate energy is presented. Advantages as well as limitations associated with these theoretical models in application to practical many-electron ion-atom, atom-atom collisions are specifically pointed out. Although a rigorous theoretical study of many-electron systems has just begun so that reports of theoretical calculations are scarce to date in comparison to flourishing experimental activities, some theoretical results are of great interest and provide important information for understanding collision dynamics of the system which contains many electrons. Selected examples are given for electron capture in a multiply charged ion-He collision, ion-pair formation in an atom-atom collision and alignment and orientation in a Li + + He collision. (Auth.)

  10. Effects of sulfide treatment on electronic transport of graphene/n-type Si Schottky diodes

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Jian-Jhou; Lin, Yow-Jon, E-mail: rzr2390@yahoo.com.tw

    2014-05-01

    The present work reports the fabrication and detailed electrical properties of graphene/n-type Si Schottky diodes with and without sulfide treatment. The graphene/n-type Si Schottky diode without sulfide treatment shows a poor rectifying behavior with an ideality factor (η) of 4.2 and high leakage. η > 2 implies that the interfacial defects influence the electronic conduction through the device. However, the graphene/n-type Si Schottky diode with sulfide treatment for 5 min shows a good rectifying behavior with η of 1.8 and low leakage. Such an improvement indicates that a good passivation is formed at the interface as a result of the reduction of the defect density. These experimental demonstrations suggest that it may be possible to minimize the adverse effects of the interface states to obtain functional devices using sulfide treatment. In addition, the graphene/n-type Si Schottky diode with sulfide treatment for 10 min shows a poor rectifying behavior with η of 2.5 and high leakage. Note, a suitable sulfide treatment time is an important issue for improving the device performance. - Highlights: • Graphene/Si diodes with sulfide treatment for 5 min show a good rectifying behavior. • Graphene/Si diodes without sulfide treatment show a poor rectifying behavior. • The interfacial defects of Schottky diodes were controlled by sulfide treatment. • Such an improvement indicates that a good passivation is formed at the interface. • A suitable sulfide treatment time is an important issue for improving performances.

  11. Effects of sulfide treatment on electronic transport of graphene/n-type Si Schottky diodes

    International Nuclear Information System (INIS)

    Zeng, Jian-Jhou; Lin, Yow-Jon

    2014-01-01

    The present work reports the fabrication and detailed electrical properties of graphene/n-type Si Schottky diodes with and without sulfide treatment. The graphene/n-type Si Schottky diode without sulfide treatment shows a poor rectifying behavior with an ideality factor (η) of 4.2 and high leakage. η > 2 implies that the interfacial defects influence the electronic conduction through the device. However, the graphene/n-type Si Schottky diode with sulfide treatment for 5 min shows a good rectifying behavior with η of 1.8 and low leakage. Such an improvement indicates that a good passivation is formed at the interface as a result of the reduction of the defect density. These experimental demonstrations suggest that it may be possible to minimize the adverse effects of the interface states to obtain functional devices using sulfide treatment. In addition, the graphene/n-type Si Schottky diode with sulfide treatment for 10 min shows a poor rectifying behavior with η of 2.5 and high leakage. Note, a suitable sulfide treatment time is an important issue for improving the device performance. - Highlights: • Graphene/Si diodes with sulfide treatment for 5 min show a good rectifying behavior. • Graphene/Si diodes without sulfide treatment show a poor rectifying behavior. • The interfacial defects of Schottky diodes were controlled by sulfide treatment. • Such an improvement indicates that a good passivation is formed at the interface. • A suitable sulfide treatment time is an important issue for improving performances

  12. Treatment of dentin with stannous fluoride - SEM and electron microprobe study

    International Nuclear Information System (INIS)

    Ellingsen, J.E.; Roella, G.

    1987-01-01

    The effect of SnF 2 -treatment of dentin surfaces was investigated by means of scanning electron microscopy (SEM) and electron microprobe analysis. Human dentin was treated with aqueous SnF 2 solutions of concentrations varying from 1 to 10%. The treatment periods lasted for 1, 5, 10 or 60 min. Both tin and fluoride were identified on the surfaces. The concentration varied depending on the extensiveness of the treatment. Immersion in 1 M KOH for 15 h removed both tin and fluoride from the surfaces. This reaction was not observed after immersion in H 2 O for the same time period. Examination of the SnF 2 -treated dentin surfaces showed a dense layer of globular particles and in addition some larger particles. The dentinal tubules were totally covered even after the treatment with the lowest concentration of SnF 2 . Deposition of tin- and fluoride-containing globules on dentin surfaces may be of clinical interest. This layer may have importance both for the caries resistance of dentin and for hypersensitivity reactions. (author)

  13. Electron beam combined with hydrothermal treatment for enhancing the enzymatic convertibility of sugarcane bagasse

    International Nuclear Information System (INIS)

    Duarte, C.L.; Ribeiro, M.A.; Oikawa, H.; Mori, M.N.; Napolitano, C.M.; Galvão, C.A.

    2012-01-01

    The use of microbial cellulolytic enzymes is the most efficient process to liberate glucose from cellulose in biomass without the formation of fermentation inhibitors. A combination of pretreatment technologies is an alternative way to increase the access of enzymes to cellulose, and consequently, the conversion yield. In this way, the present study reports on the enzymatic hydrolysis of SCB submitted to three kinds of pretreatment: electron beam processing (EBP), and EBP followed by hydrothermal (TH) and diluted acid (AH) treatment. SCB samples were irradiated using a radiation dynamics electron beam accelerator, and then submitted to thermal and acid (0.1% sulfuric acid) hydrolysis for 40 and 60 min at 180 °C. These samples were submitted to enzymatic hydrolysis (EH) using commercial preparations, including Celluclast 1.5 L and beta-glycosidase. The addition of diluted acid improved TH treatment allowing for a shorter application time. EBP with 50 kGy increased the enzymatic hydrolysis yield of cellulose by 20% after TH and 30% after AH. - Highlights: ► We study the enzymatic hydrolysis of cellulose and hemicellulose in sugarcane bagasse. ► We study the combination of three pretreatments: electron beam processing, EBP followed by hydrothermal and by diluted acid treatment. ► The electron beam processing increased the enzymatic hydrolysis from 8% to 15% with 20 kGy. ► The enzymes used were commercial preparations, as Celluclast 1.5 L and β-glycosidase. ► The EBP with 50 kGy increased on 20% the yield of EH of cellulose after TH and 30% after AH.

  14. Effect of ozonation on the biological treatability of a textile mill effluent.

    Science.gov (United States)

    Karahan, O; Dulkadiroglu, H; Kabdasli, I; Sozen, S; Babuna, F Germirli; Orhon, D

    2002-12-01

    Ozonation applied prior to biological processes, has proved to be a very effective chemical treatment step mostly for colour removal when soluble dyes are used in textile finishing operations. Its impact on biological treatability however has not been fully evaluated yet. This study evaluates the effect of ozonation on the quality of wastewater from a textile mill involving bleaching and reactive dyeing of cotton and synthetic knit fabric. The effect of ozonation on COD fractionation and kinetic coefficients defining major biological processes is emphasised. The results indicate that the extent of ozone applied greatly affects the remaining organic carbon composition in the wastewater. The relative magnitude of different COD fractions varies as a function of the ozone dose. Ozonation does not however exert a measurable impact on the rate of major biological processes.

  15. Catalyzed ozonation process with GAC and metal doped-GAC for removing organic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Oh, B.S.; Kang, J.W.; Song, S.J. [Dept. of Environmental Engineering, Yonsei Univ., Wonju Campus, Hyeung-up Myon (Korea); Oh, H.J. [Water Resources and Environmental Research Div., Korea Inst. of Construction Technology, Kyonggi-do (Korea)

    2003-07-01

    This study investigates the catalytic role of granular activated carbon (GAC) and metal (Mn or Fe) doped-GAC in transforming ozone into more reactive secondary radicals such as OH radicals for the treatment of wastewater. The GAC doped with Mn showed the highest catalytic performance of ozone decomposition into OH radical (OH{sup .}) production. Likewise, activated carbon alone could accelerate ozone decomposition, resulting in the formation of OH{sup .}s. In the presence of promoters, ozone depletion rate was enhanced further by the Mn-GAC catalyst system even in an acidic pH aqueous condition. (orig.)

  16. Clinical observation of ozone laser combined with puncture needle in the treatment of 58 patients with cervical spondylosis%臭氧激光联合穿刺针治疗颈椎病58例观察

    Institute of Scientific and Technical Information of China (English)

    顾柯; 闫宇邱; 于龙; 李岩; 刘文立; 郭洋; 魏武

    2011-01-01

    Objective: To study the therapeutic effects and safety of patent technology ozone laser combined with puncture needle in the treatment of cervical spondylosis. Methods: 58 patients with cervical spondylosis received the treatment of patent technology ozone laser combined with puncture needle (hereafter referred to as combined needle) in our department from August 2008 to February 2010. VAS score changes before and 6 months after surgery and MacNab score criteria 6 months after surgery were analyzed. Results: After 6 to 9 months' follow-up, the VAS score of preoperative neck and shoulder pain was (6.57±1.34) scores. The VAS score of 1-week postoperative neck and shoulder pain was (1.80±0.65) scores and those of 1, 3 and 6 months were all 0 (0-2) scores. The VAS score of postoperative neck and shoulder pain obviously reduced compared with that of preoperative (H= 1.680, P=0.000), and the VAS scores of postoperative neck and shoulder pain in 6 months showed no significant rebound. 6-month follow-up showed that 29 patients were excellent, 23 good and 6 fair, with the excellent and good rate of 89.6% (52/58). Conclusion: Ozone laser combined with puncture needle for the treatment of cervical spondylosis is safe and effective.%目的:研究专利技术臭氧激光联合穿刺针治疗颈椎病的疗效和安全性.方法:对我科2008年8月~2010年2月收治的58例颈椎病患者,应用专利技术臭氧激光联合穿刺针(以下简称联合针)进行臭氧激光联合治疗,分析术前及术后6个月内VAS评分的变化及术后6个月MacNab评分标准.结果:随访6~9个月,术前颈肩痛VAS评分为(6.57±1.34)分,术后1周VAS评分(1.80±0.65)分,术后颈肩痛VAS评分较术前有明显降低(H=61.680,P=0.000),术后1、3、6个月VAS评分均为0(0~2)分,术后6个月内颈肩痛VAS评分无明显反弹.6个月随访时29例优,23例良,6例可,优良率为89.6%(52/58).结论:激光臭氧联合穿刺针介入治疗颈椎病安全且疗效显著.

  17. Some cytologic aspects of ionizing radaiation and electron treatment effect of potatoes tubers

    International Nuclear Information System (INIS)

    Totadze, L.Eh.; Svanidze, S.S.

    1982-01-01

    Effect of ionizing radiation and electron treatment on the microstructure of potatoe tubers of the Majestic sort has been studied. The potatoe is subjected to alternating current and Co 60 gamma-radiation treatment (with the doses 5000 rad, 10000, 15000, 20000, 25000 and 30000 rad). A supposition is made that the pass of alternating current at the voltage of 60 V, current intensity 1 mA and the exposure of 5 min through potatoe tuber causes certain cytoplasmatic changes in somatic cells manifested in the increase of tuber rest period. During potatoe tuber treatment with Co 60 γ-radiation a direct correlation between irradiation doses and degradation of somatic cells is observed

  18. Purification and treatment of industrial wastewater by electron beam process: it's potential and effectiveness evaluation

    International Nuclear Information System (INIS)

    Zulkafli Ghazali; Khomsaton Abu Bakar; Ting Teo Ming; Siti Aiasah Hashim; Khairul Zaman Mohd Dahlan

    2002-01-01

    Demand for water has grown dramatically globally. We have seen how acute is the demand for treated water in Malaysia during dry spell of late. Between 1900 and 1995, water consumption increased by over six times, globally, more than double the rate of population growth. This rapid growth in water demand is due to the increasing reliance on irrigation to achieve food security, the growth of industries, and the increasing use for domestic purposes. Given the seriousness of the situation and future risk of crises, there is an urgent need to develop the water-efficient technologies including economical treatment methods of wastewater and polluted water. Electron beam treatment (E-Beam treatment) is a comparatively new method of wastewater purification. E-beam treatment is also an environment-friendly approach for the cleanup of contaminated groundwater and industrial wastewater. E-beam treatment treats multi-components waste streams and does not require any hazardous chemical additives nor does it create any secondary wastes. It uses fast formation of short-lived reactive particles, which are capable of efficient decomposition of pollutants inside wastewater. This paper highlights the practical treatment of wastewater using E-Beam method that gives essential conveniences and advantages of the followings: - strongest reducing and oxidizing agents; - universality and interchangeability of redox agents; - variety of paths for pollutant conversion; - process controllability; - wide choice of equipment and technological regimes; - compatibility with conventional methods. (Author)