WorldWideScience

Sample records for removal rates based

  1. High removal rate laser-based coating removal system

    Science.gov (United States)

    Matthews, Dennis L.; Celliers, Peter M.; Hackel, Lloyd; Da Silva, Luiz B.; Dane, C. Brent; Mrowka, Stanley

    1999-11-16

    A compact laser system that removes surface coatings (such as paint, dirt, etc.) at a removal rate as high as 1000 ft.sup.2 /hr or more without damaging the surface. A high repetition rate laser with multiple amplification passes propagating through at least one optical amplifier is used, along with a delivery system consisting of a telescoping and articulating tube which also contains an evacuation system for simultaneously sweeping up the debris produced in the process. The amplified beam can be converted to an output beam by passively switching the polarization of at least one amplified beam. The system also has a personal safety system which protects against accidental exposures.

  2. Modeling High Rate Phosphorus and Nitrogen Removal in a Vertical Flow Alum Sludge based Constructed Wetlands

    Science.gov (United States)

    Jeyakumar, Lordwin; Zhao, Yaqian

    2014-05-01

    Increased awareness of the impacts of diffuse pollution and their intensification has pushed forward the need for the development of low-cost wastewater treatment techniques. One of such efforts is the use of novel DASC (Dewatered Alum Sludge Cakes) based constructed wetlands (CWs) for removing nutrients, organics, trace elements and other pollutants from wastewater. Understanding of the processes in CWs requires a numerical model that describes the biochemical transformation and degradation processes in subsurface vertical flow (VF) CWs. Therefore, this research focuses on the development of a process-based model for phosphorus (P) and nitrogen (N) removal to achieve a stable performance by using DASC as a substrate in CWs treatment system. An object-oriented modelling tool known as "STELLA" which works based on the principle of system dynamics is used for the development of P and N model. The core objective of the modelling work is oriented towards understanding the process in DASC-based CWs and optimizes design criteria. The P and N dynamic model is developed for DASC-based CWs. The P model developed exclusively for DASC-based CW was able to simulate the effluent P concentration leaving the system satisfactorily. Moreover, the developed P dynamic model has identified the major P pathways as adsorption (72%) followed by plant uptake (20%) and microbial uptake (7%) in single-stage laboratory scale DASC-based CW. Similarly, P dynamic simulation model was developed to simulate the four-stage laboratory scale DASC-based CWs. It was found that simulated and observed values of P removal were in good agreement. The fate of P in all the four stages clearly shows that adsorption played a pivotal role in each stage of the system due to the use of the DASC as a substrate. P adsorption by wetland substrate/DASC represents 59-75% of total P reduction. Subsequently, plant uptake and microbial uptake have lesser role regarding P removal (as compared to adsorption).With regard

  3. Simulation-based Analysis of the Differences in the Removal Rate of Chlorides, Nitrates and Sulfates by Electrokinetic Desalination Treatments

    DEFF Research Database (Denmark)

    Paz-Garcia, Juan Manuel; Johannesson, Björn; Ottosen, Lisbeth M.

    2012-01-01

    Due to their abundance in the natural environment, chloride, nitrate and sulfate salts are considered the main responsible for the salt-induced decay processes in building materials and sculptures. Electro-desalination techniques, enhanced with carbonated clay buffer poultice placed between...... than chlorides and nitrates. A physicochemical model for electrochemically-induced reactive-transport processes is described and used for a theoretical analysis of the influence of the chemical interactions on the removal rate of the target ions. Simulations for the electro-desalination of a brick...

  4. Effect of CO2 Flow Rate on the Pinang Frond-Based Activated Carbon for Methylene Blue Removal

    Directory of Open Access Journals (Sweden)

    S. G. Herawan

    2013-01-01

    Full Text Available Activated carbons are regularly used the treatment of dye wastewater. They can be produced from various organics materials having high level of carbon content. In this study, a novel Pinang frond activated carbon (PFAC was produced at various CO2 flow rates in the range of 150–600 mL/min at activation temperature of 800°C for 3 hours. The optimum PFAC sample is found on CO2 flow rate of 300 mL/min which gives the highest BET surface area and pore volume of 958 m2/g and 0.5469 mL/g, respectively. This sample shows well-developed pore structure with high fixed carbon content of 79.74%. The removal of methylene blue (MB by 95.8% for initial MB concentration of 50 mg/L and 72.6% for 500 mg/L is achieved via this sample. The PFAC is thus identified to be a suitable adsorbent for removing MB from aqueous solution.

  5. Effect of CO2 Flow Rate on the Pinang Frond-Based Activated Carbon for Methylene Blue Removal

    Science.gov (United States)

    Herawan, S. G.; Ahmad, M. A.; Putra, A.; Yusof, A. A.

    2013-01-01

    Activated carbons are regularly used the treatment of dye wastewater. They can be produced from various organics materials having high level of carbon content. In this study, a novel Pinang frond activated carbon (PFAC) was produced at various CO2 flow rates in the range of 150–600 mL/min at activation temperature of 800°C for 3 hours. The optimum PFAC sample is found on CO2 flow rate of 300 mL/min which gives the highest BET surface area and pore volume of 958 m2/g and 0.5469 mL/g, respectively. This sample shows well-developed pore structure with high fixed carbon content of 79.74%. The removal of methylene blue (MB) by 95.8% for initial MB concentration of 50 mg/L and 72.6% for 500 mg/L is achieved via this sample. The PFAC is thus identified to be a suitable adsorbent for removing MB from aqueous solution. PMID:24027443

  6. Ammonia removal in anaerobic digestion by biogas stripping: an evaluation of process alternatives using a first order rate model based on experimental findings

    OpenAIRE

    Walker, Mark; Iyer, K.; Heaven, S.; Banks, C.J.

    2011-01-01

    The feasibility of biogas stripping to remove ammonia in the anaerobic digestion of source segregated food waste was investigated. It was found in batch experiments that ammonia could be removed from digestate and that the removal followed 1st order kinetics with respect to total ammonia nitrogen concentration. Increasing temperature, biogas flow rate and initial pH all increased removal rates. Using kinetic data gathered in these experiments allowed the integration of ammonia stripping with ...

  7. Rates of calcium carbonate removal from soils.

    NARCIS (Netherlands)

    Breemen, van N.; Protz, R.

    1988-01-01

    Mean annual rates of calcium carbonate removal from soils in a subarctic climate estimated from data on two chronosequences of calcareous storm ridges, appeared to be relatively constant through time. Concentrations of dissolved calcium carbonate in the soil solution in the study sites calculated

  8. Improved sulphate removal rates at increased sulphide ...

    African Journals Online (AJOL)

    Improved sulphate removal rates at increased sulphide concentration in the sulphidogenic bioreactor. ... The results of three investigations operating a continuous reactor, a column reactor and batch-test reactors have shown that increased sulphide concentrations have resulted in improved biological sulphate reduction.

  9. Laser-based coatings removal

    Energy Technology Data Exchange (ETDEWEB)

    Freiwald, J.G.; Freiwald, D.A. [F2 Associates, Inc., Albuquerque, NM (United States)

    1995-10-01

    Over the years as building and equipment surfaces became contaminated with low levels of uranium or plutonium dust, coats of paint were applied to stabilize the contaminants in place. Most of the earlier paint used was lead-based paint. More recently, various non-lead-based paints, such as two-part epoxy, are used. For D&D (decontamination and decommissioning), it is desirable to remove the paints or other coatings rather than having to tear down and dispose of the entire building. This report describes the use of pulse-repetetion laser systems for the removal of paints and coatings.

  10. Material removal mechanism and material removal rate model of polishing process for quartz glass using soft particle

    Science.gov (United States)

    Liu, Defu; Chen, Guanglin; Hu, Qing

    2015-10-01

    Fiber arrays are used to connect arrayed waveguide chips. The end-faces of fiber array components are multi-materials non-uniform surfaces. Their low polishing quality has become a bottleneck that restricts coupling performance of integrated photo-electronic devices. The chemical mechanical polishing (CMP) is normally used to improve the polishing quality of the end-faces of fiber array components. It is very important to optimize process parameters by researching the mechanical behavior of nanoparticles and material microstructure evolution on the CMP interfaces. Based on the elastic and hyper-elastic contact of the soft polishing particle with quartz glass and polishing pad, the material removal mechanism at molecular scale of polishing process for quartz glass using soft polishing particles is investigated, and the material removal rate model is also derived by using Arrhenius theory and molecule vibration theory. Theoretical and experimental results show that the material is mainly removed by the interfacial tribo-chemical effect between polishing particle and quartz glass during CMP process. The depth of a single particle embedding into the quartz glass is at molecular scale, and the superficial molecules of quartz glass are removed by chemical reactions because of enough energy obtained. The material removal rate of quartz glass during CMP process is determined by the polishing pressure, the chemical reagents and its concentration, and the relative movement speed between the quartz glass workpiece and the polishing pad.

  11. Rate and extent NOM removal during oxidation and biofiltration.

    Science.gov (United States)

    Black, Kerry E; Bérubé, Pierre R

    2014-04-01

    The presence of natural organic matter (NOM) in drinking water treatment presents many challenges. Integrated treatment processes combining oxidation and biofiltration have been demonstrated to be very effective at reducing NOM, specifically biodegradable organics. Laboratory bench-scale experiments were carried out to investigate the effect of oxidation by ozonation or UV/H2O2 on NOM. Specifically the rate of biodegradation was studied by performing bench-scale biodegradation experiments using acclimatized biological activated carbon (BAC). For the source water investigated, oxidation did not preferentially react with the biodegradable or non-biodegradable NOM. In addition, the type or dose of oxidation applied did not affect the observed rate of biodegradation. The rate kinetics for biodegradation were constant for all oxidation conditions investigated. Oxidation prior to biofiltration increased the overall removal of organic matter, but did not affect the rate of biodegradation of NOM. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Rate based failure detection

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Brett Emery Trabun; Gamage, Thoshitha Thanushka; Bakken, David Edward

    2018-01-02

    This disclosure describes, in part, a system management component and failure detection component for use in a power grid data network to identify anomalies within the network and systematically adjust the quality of service of data published by publishers and subscribed to by subscribers within the network. In one implementation, subscribers may identify a desired data rate, a minimum acceptable data rate, desired latency, minimum acceptable latency and a priority for each subscription. The failure detection component may identify an anomaly within the network and a source of the anomaly. Based on the identified anomaly, data rates and or data paths may be adjusted in real-time to ensure that the power grid data network does not become overloaded and/or fail.

  13. Oxidation mechanism and overall removal rates of endocrine disrupting chemicals by aquatic plants.

    Science.gov (United States)

    Reis, A R; Tabei, K; Sakakibara, Y

    2014-01-30

    The purpose of this study was to evaluate experimentally and theoretically the oxidation mechanisms and overall removal rates of phenolic endocrine disrupting chemicals (EDCs) by aquatic plants. EDCs used in this study were bisphenol-A (BPA), 2,4-dichlorophenol (2,4-DCP), 4-tert-octylphenol (4-t-OP), and pentachlorophenol (PCP). Referring to reported detection levels in aquatic environments and contaminated sites, the feed concentration of each EDC was set from 1 to 100μg/L. Experimental results showed that, except for PCP, phenolic EDCs were stably and concurrently removed by different types of aquatic plants over 70 days in long-term continuous treatments. Primal enzymes responsible for oxidation of BPA, 2,4-DCP, and 4-t-OP were peroxidases (POs). Moreover, enzymatic removal rates of BPA, 2,4-DCP, and 4-t-OP by POs were more than 2 orders of magnitude larger than those by aquatic plants. Assuming that overall removal rates of EDCs are controlled by mass transfer rates onto liquid films on the surface of aquatic plants, an electrochemical method based on the limiting current theory was developed to measure the mass transfer rates of EDCs. Because of extremely large removal rates of EDCs by POs, observed removal rates by aquatic plants were in reasonably good agreement with calculated results by a mathematical model developed based on an assumption that mass transfer limitation is a rate-limiting step. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  14. Tunable removal rates of silicon dioxide, silicon nitride and polysilicon films during chemical mechanical polishing

    Science.gov (United States)

    Dandu, Veera P. R.

    Achieving a high Si3N4 removal rate and a relatively low SiO2 removal rate, which is challenging but promising for emerging applications for sub-32 nm node devices, was investigated. This was thought to be impossible as the removal of Si3N4 usually follows a two-step mechanism in which silicon nitride is hydrolyzed first and then removed during CMP. Therefore, additives normally used to suppress the SiO 2 removal rate would tend to suppress the S3N4 removal rate as well. However, it was shown that by using a specific type of a cationic polymer in ceria-based dispersions, a low SiO2 removal rate (FinFET fabrication, where a polysilicon layer has to be selectively polished/protected with respect to silicon dioxide and/or silicon nitride layers. Several dispersions were identified which yield tunable removal rates of polysilicon (from <2 nm/min to ˜1 microm/min), silicon dioxide (<2 nm/min to ˜500 nm/min) and silicon nitride (<2 nm/min to ˜120 nm/min) films. This has been made possible by using several additives in ceria and silica based dispersions with and without surface functionalization at different pH values. A fundamental investigation of the interaction of the additive(s) with the abrasives, SiO2 Si3N4, and polysilicon films was also carried out in order to elucidate the removal mechanisms. Zeta potential measurements, UV-Vis Spectroscopy, adsorption isotherms and thermo gravimetric analysis were performed to understand the adsorption behavior of these additives on abrasives and polishing films at different pH values. It was observed that the Ce3+ on the surface of the ceria abrasives is reacting with the silicon dioxide and suboxide on the silicon nitride surfaces during polishing. Also, it appears that electrostatic interactions in conjunction with the reactivity of the active sites on the surface of abrasives play a vital role in determining the removal rates of silicon dioxide, silicon nitride and polysilicon films.

  15. Epidemiological Data and Survival Rate of Removable Partial Dentures

    Science.gov (United States)

    Moreno, Amália; Haddad, Marcela Filié; Rocha, Eduardo Passos; Assunção, Wirley Gonçalves; Filho, Humberto Gennari; Santos, Emerson Gomes Dos; Sonego, Mariana Vilela; Santos, Daniela Micheline Dos

    2016-01-01

    Introduction The use of removable partial denture (RPD) is considered as low-cost and common treatment option to rehabilitate edentulous areas. Aim This study aimed to investigate the epidemiological data of patients rehabilitated with removable partial denture (RPD) in order to assess treatment survival rate and failures. Materials and Methods Epidemiological data and medical records of patients treated with RPD between 2007 and 2012 at the RPD discipline of a Brazilian University (Aracatuba Dental School- UNESP) were evaluated as well as dental records of patients who underwent RPD treatments (fabrication or repairs) between 2000 and 2010. Factors such as gender, age, presence of systemic disease, main complaint, edentulous arch, period and cause of denture replacement and the prosthesis characteristics were recorded. The chi-square test was used to assess the differences between the variables and the Kaplan Meyer to assess the survival of the RPDs evaluated. Results A total of 324 maxillary RPD and 432 mandibular RPD were fabricated. Most of the patients were women aging 41 to 60-year-old. The number of mandibular RPD Kennedy class I (26%) was statistically higher for the maxillary arch (p<.05). There was no association between main complaint to gender or the presence of systemic disease. The lingual plate was the most common major connector used in the mandible (32%). The main reason for altering the design of replaced RPDs were changes during treatment plan. Conclusion The number of patients who require RPD is large; most of RPDs are Kennedy Class I. A good treatment plan is very important for achieving a positive treatment outcome, and it is strictly related to the survival rate. PMID:27437367

  16. Polymerase chain reaction-based gene removal from plasmids

    Directory of Open Access Journals (Sweden)

    Vishnu Vardhan Krishnamurthy

    2015-09-01

    Full Text Available This data article contains supplementary figures and methods to the research article entitled, “Multiplex gene removal by two-step polymerase chain reactions” (Krishnamurthy et al., Anal. Biochem., 2015, doi:http://dx.doi.org/10.1016/j.ab.2015.03.033, which presents a restriction-enzyme free method to remove multiple DNA segments from plasmids. Restriction-free cloning methods have dramatically improved the flexibility and speed of genetic manipulation compared to conventional assays based on restriction enzyme digestion (Lale and Valla, 2014. DNA Cloning and Assembly Methods, vol. 1116. Here, we show the basic scheme and characterize the success rate for single and multiplex gene removal from plasmids. In addition, we optimize experimental conditions, including the amount of template, multiple primers mixing, and buffers for DpnI treatment, used in the one-pot reaction for multiplex gene removal.

  17. Tetracycline removal during wastewater treatment in high-rate algal ponds

    Energy Technology Data Exchange (ETDEWEB)

    Godos, Ignacio de [School of Engineering and Advanced Technology, Massey University, Private Bag 11222, Palmerston North (New Zealand); Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011, Valladolid (Spain); Department of Biodiversity and Environmental Management, University of Leon, Campus Vegazana, 24071 Leon (Spain); Munoz, Raul [Department of Chemical Engineering and Environmental Technology, University of Valladolid, Dr. Mergelina s/n, 47011, Valladolid (Spain); Guieysse, Benoit, E-mail: B.J.Guieysse@massey.ac.nz [School of Engineering and Advanced Technology, Massey University, Private Bag 11222, Palmerston North (New Zealand)

    2012-08-30

    Highlights: Black-Right-Pointing-Pointer Tetracycline removal was most likely caused by photodegradation and biosorption. Black-Right-Pointing-Pointer Tetracycline presence was linked to biomass deflocculation and poor settleability. Black-Right-Pointing-Pointer Deflocculation did not impact treatment efficiency. Black-Right-Pointing-Pointer Deflocculation may hamper biomass recover during full-scale treatment. - Abstract: With the hypothesis that light supply can impact the removal of veterinary antibiotics during livestock wastewater treatment in high rate algal ponds (HRAPs), this study was undertaken to determine the mechanisms of tetracycline removal in these systems. For this purpose, two HRAPs were fed with synthetic wastewater for 46 days before tetracycline was added at 2 mg L{sup -1} to the influent of one of the reactors (Te-HRAP). From day 62, dissolved tetracycline removal stabilized around 69 {+-} 1% in the Te-HRAP and evidence from batch assays suggests that this removal was mainly caused by photodegradation and biosorption. Tetracycline addition was followed by the deflocculation of the Te-HRAP biomass but had otherwise no apparent impact on the removal of the chemical oxygen demand (COD) and biomass productivity. The results from the batch assays also suggested that the light-shading and/or pollutant-sequestrating effects of the biomass limited tetracycline removal in the pond. For the first time, these results demonstrate that the shallow geometry of HRAPs is advantageous to support the photodegradation of antibiotics during wastewater biological treatment but that the presence of these pollutants could hamper biomass recovery. These findings have significant implications for algal-based environmental biotechnologies and must be confirmed under field conditions.

  18. Complication rates and patient satisfaction with removable dentures.

    Science.gov (United States)

    Bilhan, Hakan; Erdogan, Ozge; Ergin, Selen; Celik, Melahat; Ates, Gokcen; Geckili, Onur

    2012-05-01

    The purpose of this clinical study was to evaluate the frequency and type of prosthetic complications in relation to type and properties of removable dentures and to investigate the influence of these complications and several data about the existing dentures on patient satisfaction. Ninety nine patients (44 males and 55 females) wearing removable dentures have been included in the study. The complications of the patients were recorded; patient satisfaction was determined with a Visual Analog Scale (VAS) and the relationship of complications and patient satisfaction with several data about the dentures such as denture age, type of denture, centric relation and vertical dimension was investigated. Kruskal Wallis, Mann Whitney U and Chi square tests were used for statistical analyses. The results were evaluated statistically at a significance level of Pdentures with correct centric relations was found to be significantly lower than dentures with wrong centric relations (Pdentures with wrong centric relations caused need for addition of artificial teeth.

  19. Uncertainties of stormwater characteristics and removal rates of stormwater treatment facilities: implications for stormwater handling.

    Science.gov (United States)

    Langeveld, J G; Liefting, H J; Boogaard, F C

    2012-12-15

    Stormwater runoff is a major contributor to the pollution of receiving waters. This study focuses at characterising stormwater in order to be able to determine the impact of stormwater on receiving waters and to be able to select the most appropriate stormwater handling strategy. The stormwater characterisation is based on determining site mean concentrations (SMCs) and their uncertainties as well as the treatability of stormwater by monitoring specific pollutants concentration levels (TSS, COD, BOD, TKN, TP, Pb, Cu, Zn, E.coli) at three full scale stormwater treatment facilities in Arnhem, the Netherlands. This has resulted in 106 storm events being monitored at the lamella settler, 59 at the high rate sand filter and 132 at the soil filter during the 2 year monitoring period. The stormwater characteristics in Arnhem in terms of SMCs for main pollutants TSS and COD and settling velocities differ from international data. This implies that decisions for stormwater handling made on international literature data will very likely be wrong due to assuming too high concentrations of pollutants and misjudgement of the treatability of stormwater. The removal rates monitored at the full scale treatment facilities are within the expected range, with the soil filter and the sand filter having higher removal rates than the lamella settler. The full scale pilots revealed the importance of incorporating gross solids removal in the design of stormwater treatment facilities, as the gross solids determine operation and maintenance requirements. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Complication rates and patient satisfaction with removable dentures

    Science.gov (United States)

    Bilhan, Hakan; Erdogan, Ozge; Ergin, Selen; Celik, Melahat; Ates, Gokcen

    2012-01-01

    PURPOSE The purpose of this clinical study was to evaluate the frequency and type of prosthetic complications in relation to type and properties of removable dentures and to investigate the influence of these complications and several data about the existing dentures on patient satisfaction. MATERIALS AND METHODS Ninety nine patients (44 males and 55 females) wearing removable dentures have been included in the study. The complications of the patients were recorded; patient satisfaction was determined with a Visual Analog Scale (VAS) and the relationship of complications and patient satisfaction with several data about the dentures such as denture age, type of denture, centric relation and vertical dimension was investigated. Kruskal Wallis, Mann Whitney U and Chi square tests were used for statistical analyses. The results were evaluated statistically at a significance level of Pdentures with correct centric relations was found to be significantly lower than dentures with wrong centric relations (Pdentures with wrong centric relations caused need for addition of artificial teeth. PMID:22737317

  1. High rates of denitrification and nitrate removal in cold seep sediments.

    Science.gov (United States)

    Bowles, Marshall; Joye, Samantha

    2011-03-01

    We measured denitrification and nitrate removal rates in cold seep sediments from the Gulf of Mexico. Heterotrophic potential denitrification rates were assayed in time-series incubations. Surficial sediments inhabited by Beggiatoa exhibited higher heterotrophic potential denitrification rates (32 μM N reduced day(-1)) than did deeper sediments (11 μM N reduced day(-1)). Nitrate removal rates were high in both sediment horizons. These nitrate removal rates translate into rapid turnover times (cycling at cold seeps and the requirement for novel mechanisms to provide nitrate to the sediment microbial community.

  2. Aluminum-Based Water Treatment Residue Reuse for Phosphorus Removal

    Directory of Open Access Journals (Sweden)

    Lai Yoke Lee

    2015-04-01

    Full Text Available Aluminum-based water treatment residue (Al-WTR generated during the drinking water treatment process is a readily available recycled material with high phosphorus (P adsorption capacity. The P adsorption capacity of Al-WTR generated from Singapore’s water treatment plant was evaluated with reference to particle size range, adsorption pH and temperature. Column tests, with WTR amendments in sand with and without compost, were used to simulate the bioretention systems. The adsorption rate decreased with increasing WTR sizes. Highest P adsorption capacity, 15.57 mg PO43−-P/g WTR, was achieved using fine WTR particles (>50% particles at less than 0.30 mm. At pH 4, the contact time required to reduce effluent P concentration to below the detectable range was half compared with pH 7 and 9. The adsorption rate observed at 40 ± 2 °C was 21% higher compared with that at 30 ± 2 °C. Soil mixes amended with 10% WTR and compost were able to maintain consistently high (90% total phosphorus (TP removal efficiency at a TP load up to 6.45 g/m3. In contrast, TP removal efficiencies associated with columns without WTR amendment decreased to less than 45% as the TP load increased beyond 4.5 g/m3. The results showed that WTR application is beneficial for enhanced TP removal in bioretention systems.

  3. High Metal Removal Rate Process for Machining Difficult Materials

    Energy Technology Data Exchange (ETDEWEB)

    Bates, Robert; McConnell, Elizabeth

    2016-06-29

    Machining methods across many industries generally require multiple operations to machine and process advanced materials, features with micron precision, and complex shapes. The resulting multiple machining platforms can significantly affect manufacturing cycle time and the precision of the final parts, with a resultant increase in cost and energy consumption. Ultrafast lasers represent a transformative and disruptive technology that removes material with micron precision and in a single step manufacturing process. Such precision results from athermal ablation without modification or damage to the remaining material which is the key differentiator between ultrafast laser technologies and traditional laser technologies or mechanical processes. Athermal ablation without modification or damage to the material eliminates post-processing or multiple manufacturing steps. Combined with the appropriate technology to control the motion of the work piece, ultrafast lasers are excellent candidates to provide breakthrough machining capability for difficult-to-machine materials. At the project onset in early 2012, the project team recognized that substantial effort was necessary to improve the application of ultrafast laser and precise motion control technologies (for micromachining difficult-to-machine materials) to further the aggregate throughput and yield improvements over conventional machining methods. The project described in this report advanced these leading-edge technologies thru the development and verification of two platforms: a hybrid enhanced laser chassis and a multi-application testbed.

  4. Biotechnology based processes for arsenic removal

    NARCIS (Netherlands)

    Huisman, J.; Olde Weghuis, M.; Gonzalez-Contreras, P.A.

    2011-01-01

    The regulations for arsenic control have become strict. Therefore, better technologies to remove arsenic from bleeds and effluents are desired. In addition, no single solution is suitable for all cases. The properties of the process streams and the storage facilities are major factors determining

  5. Rapid startup and high rate nitrogen removal from anaerobic sludge digester liquor using a SNAP process.

    Science.gov (United States)

    Qiao, Sen; Nishiyama, Takashi; Fujii, Tatsuo; Bhatti, Zafar; Furukawa, Kenji

    2012-02-01

    In this study, a single-stage autotrophic nitrogen removal reactor, packed with a novel acrylic fiber biomass carrier material (Biofix), was applied for nitrogen removal from sludge digester liquor. For rapid start-up, conventional activated sludge was added to the reactor soon after the attachment of anammox biomass on the Biofix carriers, which allowed conventional activated sludge to form a protective layer of biofilm around the anammox biomass. The Nitrogen removal efficiency reached 75% within 1 week at a nitrogen loading rate of 0.46 kg-N/m(3)/day for synthetic wastewater treatment. By the end of the synthetic wastewater treatment period, the maximum nitrogen removal rate had increased to 0.92 kg-N/m(3)/day at a nitrogen loading rate of 1.0 kg-N/m(3)/day. High nitrogen removal rate was also achieved during the actual raw digester liquor treatment with the highest nitrogen removal rate being 0.83 kg-N/m(3)/day at a nitrogen loading rate of 0.93 kg-N/m(3)/day. The thick biofilm on Biofix carriers allowed anammox bacteria to survive under high DO concentration of 5-6 mg/l resulting in stable and high nitrogen removal performance. FISH and CLSM analysis demonstrated that anammox bacteria coexisted and surrounded by ammonium oxidizing bacteria.

  6. 75 FR 61050 - Removal From Regulation FD of the Exemption for Credit Rating Agencies

    Science.gov (United States)

    2010-10-04

    ... COMMISSION 17 CFR Part 243 Removal From Regulation FD of the Exemption for Credit Rating Agencies AGENCY... Securities and Exchange Commission amend Regulation FD to remove the specific exemption from the rule for... Commission is deleting Rule 100(b)(2)(iii) \\1\\ under Regulation FD.\\2\\ \\1\\ 17 CFR 243.100(b)(2)(iii). \\2\\ 17...

  7. Nitrate removal from groundwater using constructed wetlands under various hydraulic loading rates.

    Science.gov (United States)

    Lin, Ying-Feng; Jing, Shuh-Ren; Lee, Der-Yuan; Chang, Yih-Feng; Shih, Kai-Chung

    2008-11-01

    This study set up two flow-through pilot-scale constructed wetlands with the same size but various flow patterns (free water surface flow (FWS) and subsurface flow (SSF)) to receive a nitrate-contaminated groundwater. The effects of hydraulic loading rate (HLR) on nitrate removal as well as the difference in performance between the various types of wetlands were investigated. Nitrate removal rates of both wetlands increased with increasing HLR until a maximum value was reached. The maximum removal rates, occurred at HLR of 0.12 and 0.07 m d(-1), were 0.910 and 1.161 g N m(-2)d(-1) for the FWS and SSF wetland, respectively. After the maximum values were reached, further increasing HLR led to a considerable decrease in nitrate removal rate. Nitrate removal efficiencies remained high (>85%) and effluent nitrate concentrations always satisfied drinking water standard (NO3-NL(-1)) when HLR did not exceed 0.04 m d(-1) for both FWS and SSF wetlands. The first-order nitrate removal rate constant tends to decrease with increasing HLRs. The FWS wetland provided significantly higher (pwetland, while the SSF wetland exhibited significantly (pwetland. However, there was no significant difference (p>0.05) in nitrate removal performance between the two types of constructed wetlands in this study except in one trial operating at HLR of 0.06-0.07 m d(-1).

  8. Intuitive Understanding of Base Rates

    DEFF Research Database (Denmark)

    Austin, Laurel

    Purpose: This study examines whether physicians and other adults intuitively understand that the probability a positive test result is a true positive (positive predictive value, PPV) depends on the base rate of disease in the population tested. In particular, this research seeks to examine perce...... in screening versus diagnostic testing may have implications for how people, including medical doctors, understand and contribute to debates about the benefits and harms of mass screening programs....

  9. Growth rate, organic carbon and nutrient removal rates of Chlorella sorokiniana in autotrophic, heterotrophic and mixotrophic conditions.

    Science.gov (United States)

    Kim, Sunjin; Park, Jeong-eun; Cho, Yong-Beom; Hwang, Sun-Jin

    2013-09-01

    This study sought to investigate the growth rate and organic carbon and nutrient removal efficiency of Chlorella sorokiniana under autotrophic, heterotrophic and mixotrophic conditions. Growth rates of the microalgae were 0.24 d(-1), 0.53 d(-1) and 0.44 d(-1) in autotrophic, heterotrophic and mixotrophic conditions, respectively. The growth rate of C. sorokiniana was significantly higher for that grown under heterotrophic conditions. The nitrogen removal rates were 13.1 mg-N/L/day, 23.9 mg-N/L/day and 19.4 mg-N/L/day, respectively. The phosphorus removal rates reached to 3.4 mg-P/L/day, 5.6 mg-P/L/day and 5.1 mg-P/L/day, respectively. Heterotrophic conditions were superior in terms of the microalgae growth and removal of nitrogen and phosphorus compared to autotrophic and mixotrophic conditions, suggesting that microalgae cultured under this condition would be most useful for application in wastewater treatment systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Intensified nitrogen removal of constructed wetland by novel integration of high rate algal pond biotechnology.

    Science.gov (United States)

    Ding, Yi; Wang, Wei; Liu, Xingpo; Song, Xinshan; Wang, Yuhui; Ullman, Jeffrey L

    2016-11-01

    High rate algal pond (HRAP) was combined with constructed wetland (CW) to intensify nitrogen removal through optimizing nitrification and denitrification. Nitrification and denitrification process mainly depends on the oxygen content and carbon source level in CWs. Algal biomass was enriched in HRAP, and dissolved oxygen (DO) concentration was increased via photosynthesis. Algal debris increased COD as degradable bioresource. The results showed that HRAP-CW hybrid systems effectively promoted the nitrogen removal performance due to rich DO and COD. The extension of hydraulic retention time in HRAP significantly improved NH4-N and TN removals by 10.9% and 11.1% in hybrid systems, respectively. The highest NH4-N and TN removals in hybrid systems respectively reached 67.2% and 63.5%, which were significantly higher than those in single CW. The study suggested that the hybrid system had the application potentials in nitrogen removal from wastewater. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. effect of turning parameters on metal removal and tool wear rates of ...

    African Journals Online (AJOL)

    user

    desired quality of the finished product at reduced machining time and cost. The present study ... most significant process parameter for MRR with a percentage contribution of the cutting ... Keywords: Orthogonal array, Robust design, Tool wear rate, Metal removal rate. 1. ... performance of a system, part or component while.

  12. Aqueous-based thick photoresist removal for bumping applications

    Science.gov (United States)

    Moore, John C.; Brewer, Alex J.; Law, Alman; Pettit, Jared M.

    2015-03-01

    Cleaning processes account for over 25% of processing in microelectronic manufacturing [1], suggesting electronics to be one of the most chemical intensive markets in commerce. Industry roadmaps exist to reduce chemical exposure, usage, and waste [2]. Companies are encouraged to create a safer working environment, or green factory, and ultimately become certified similar to LEED in the building industry [3]. A significant step in this direction is the integration of aqueous-based photoresist (PR) strippers which eliminate regulatory risks and cut costs by over 50%. One of the largest organic solvent usages is based upon thick PR removal during bumping processes [4-6]. Using market projections and the benefits of recycling, it is estimated that over 1,000 metric tons (mt) of residuals originating from bumping processes are incinerated or sent to a landfill. Aqueous-based stripping would eliminate this disposal while also reducing the daily risks to workers and added permitting costs. Positive-tone PR dissolves in aqueous strippers while negative-tone systems are lifted-off from the substrate, bumps, pillars, and redistribution layers (RDL). While the wafers are further processed and rinsed, the lifted-off PR is pumped from the tank, collected onto a filter, and periodically back-flushed to the trash. The PR solids become a non-hazardous plastic waste while the liquids are mixed with the developer stream, neutralized, filtered, and in most cases, disposed to the sewer. Regardless of PR thickness, removal processes may be tuned to perform in <15min, performing at rates nearly 10X faster than solvents with higher bath lives. A balanced formula is safe for metals, dielectrics, and may be customized to any fab.

  13. Effect of HCO3- concentration on anammox nitrogen removal rate in a moving bed biofilm reactor.

    Science.gov (United States)

    Zekker, Ivar; Rikmann, Ergo; Tenno, Toomas; Vabamäe, Priit; Kroon, Kristel; Loorits, Liis; Saluste, Alar; Tenno, Taavo

    2012-01-01

    Anammox biomass enriched in a moving bed biofilm reactor (MBBR) fed by actual sewage sludge reject water and synthetically added NO2- was used to study the total nitrogen (TN) removal rate of the anammox process depending on bicarbonate (HCO3-) concentration. MBBR performance resulted in the maximum TN removal rate of 1100 g N m(-3) d(-1) when the optimum HCO3- concentration (910 mg L(-1)) was used. The average reaction ratio of NO2- removal, NO3- production and NH4+ removal were 1.18/0.20/1. When the HCO3- concentration was increased to 1760mg L(-1) the TN removal rate diminished to 270 g N m(-3) d(-1). The process recovered from bicarbonate inhibition within 1 week. The batch tests performed with biomass taken from the MBBR showed that for the HCO3- concentration of 615 mg L(-1) the TN removal rate was 3.3 mg N L(-1) h(-1), whereas for both lower (120 mg L(-1)) and higher (5750 mg L(-1)) HCO3- concentrations the TN removal rates were 2.3 (+/- 0.15) and 1.6 (+/- 0.12) mg N L(-1) d(-1), respectively. PCR and DGGE analyses resulted in the detection of uncultured Planctomycetales bacterium clone P4 and, surprisingly, low-oxygen-tolerant aerobic ammonia oxidizers. The ability of anammox bacteria for mixotrophy was established by diminished amounts of nitrate produced when comparing the experiments with an organic carbon source and an inorganic carbon source.

  14. Near-ultraviolet removal rates for subgingival dental calculus at different irradiation angles

    Science.gov (United States)

    Schoenly, Joshua E.; Seka, Wolf D.; Rechmann, Peter

    2011-07-01

    The laser ablation rate of subgingival dental calculus irradiated at a 400-nm-wavelength, 7.4-mJ pulse energy, and 85- and 20-deg irradiation angles is measured using laser triangulation. Three-dimensional images taken before and after irradiation create a removal map with 6-μm axial resolution. Fifteen human teeth with subgingival calculus are irradiated in vitro under a cooling water spray with an ~300-μm-diam, tenth-order super-Gaussian beam. The average subgingival calculus removal rates for irradiation at 85 and 20 deg are 11.1+/-3.6 and 11.5+/-5.9 μm/pulse, respectively, for depth removal and 4.5+/-1.7×105 and 4.8+/-2.3×105 μm3/pulse, respectively, for volume removal. The ablation rate is constant at each irradiation site but varies between sites because of the large differences in the physical and optical properties of calculus. Comparison of the average depth- and volume-removal rates does not reveal any dependence on the irradiation angle and is likely due to the surface topology of subgingival calculus samples that overshadows any expected angular dependence.

  15. Effect of filtration rate on coal-sand dual-media filter performances for microalgae removal.

    Science.gov (United States)

    Sabiri, Nour-Eddine; Monnier, Elodie; Raimbault, Virginie; Massé, Anthony; Séchet, Véronique; Jaouen, Pascal

    2017-02-01

    This study tested the efficiency of granular filtration using a bilayer sand filter for microalgae removal from culture dilutions ranging from 10,000 to 17,000 cells/mL. The objective is to evaluate the removal capacity of the filter without chemical coagulation. Two filter media, sand and anthracite, with mean grain sizes of 0.395 and 1.2 mm, respectively, were used in constant-flow-rate experiments (down-flow mode) with suspensions containing Heterocapsa triquetra microalga. The conventional rapid filtration which usually operates at a constant rate of approximately 5 m3/m2 h is compared to high-rate filtration. Two filtration velocities (5 and 10 m/h) were investigated with bed depth of 1100 mm. Average microalgal cell removal rates were 90% at 5 m/h and 68% at 10 m/h. Turbidity removal was more than 71% at 5 m/h but just 57% at 10 m/h. Head losses did not increase significantly, and values measured at process end were 32 mbar at 5 m/h and 78 mbar at 10 m/h. Retention probabilities were calculated from experimental data. A theoretical model was used to evaluate the contributions of the different drivers of microalgae removal. Hypotheses are developed on the understanding of change in the mechanisms of retention as a function of filtration velocity.

  16. Assessment of the pharmacokinetics, removal rate of hemodialysis, and safety of lactulose in hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Cheng-Jui Lin

    2016-10-01

    Full Text Available Lactulose is often used to treat hepatic encephalopathy or constipation, and also exhibits benefits to chronic renal insufficiency due to reduce nitrogen-related products in serum. The present study investigated the pharmacokinetics of lactulose, its removal rate through dialysis, and safety by administering lactulose 6.5 g (Lagnos Jelly Divided Pack 16.05 g orally to six hemodialysis patients who resided in Taiwan. As a result, the means of maximum plasma concentrations (Cmax and Time to reach Cmax (Tmax were 3090 ± 970 ng/mL and 6.5 ± 2.3 hours, respectively. The mean plasma concentration was 2220 ± 986 ng/mL after administration for 24 hours. Sequentially, the mean plasma concentration reduced to 307 ± 117 ng/mL after the application of 4-hour dialysis. Area under the plasma concentration-time curve from zero to 24 h post-dose (AUC0–24h were 56,200 ± 21,300 ng h/mL and the AUC0–28h was 61,200 ± 23,300 ng h/mL. The rate of lactulose removal by dialysis was 83.6 ± 8.9%. In addition, the multiple doses of lactulose using a simulated model suggested that no plasma accumulation would be expected while coordinating with dialysis. Good tolerability was confirmed, while the mild adverse effect of diarrhea was observed in one case during the study period. No death or serious adverse effect was reported. Based on the present study, we demonstrated the pharmacokinetic transition with respect to plasma levels of lactulose in patients with impaired renal excretion treated with hemodialysis.

  17. Determination of ozone removal rates by selected building products using the FLEC emission cell.

    Science.gov (United States)

    Klenø, J G; Clausen, P A; Weschler, C J; Wolkoff, P

    2001-06-15

    Ozone removal by 16 aged (older than 1-120 months) but unused building products or materials was studied in a test system that included the field and laboratory emission cell (FLEC). The ozone removal was studied at 50 +/- 1 ppb ozone, a relative humidity of 50 +/- 5%, a temperature of 21 +/- 2 degrees C, and an air flow rate of 900 +/- 10 mL min(-1) through the FLEC (air velocity ca. 3 cm s(-1)). The ozone removal increased rapidly during the first 1-2 min and either remained at a constant level or decreased asymptotically to reach a steady state-like value. The ozone removal profiles for a given material showed good repeatability during replicate experiments. Ozone deposition velocities for the building products were calculated to be between 0.0007 cm s(-1) (lacquered ash) and 0.8 cm s(-1) (unpainted gypsum board).

  18. Virus removal within a soil infiltration zone as affected by effluent composition, application rate, and soil type.

    Science.gov (United States)

    Van Cuyk, Sheila; Siegrist, Robert L

    2007-02-01

    The column studies presented in this paper simulated the infiltrative surface of onsite wastewater systems where effluent is applied and where a biomat may form. Two bacteriophages, MS-2 and PRD-1, were used as surrogates for human pathogenic enteric viruses during two tracer tests. A vacuum manifold was used to simulate the drainage effects of an underlying unsaturated soil profile, allowing for the collection of percolate samples at 4 cm immediately below the infiltrative surface. The impact of effluent applied (septic tank effluent (STE) or a simulated ground water), soil type (medium sand or sandy loam), hydraulic loading rate (5 or 25 cm/day) and method of application (four equivalent daily doses or 24 equivalent micro-doses per day) on the removal of viruses were investigated. These unsaturated mini column experiments demonstrated that the removal of viruses within an infiltrative surface zone (of approximately 4 cm) generally improved over time under the conditions studied. An exception occurred in sand-filled columns dosed with STE where the removal of PRD-1 decreased after a period of effluent application. Statistical analysis conducted on the calculated percent removal demonstrated that the quality of the effluent applied to the infiltrative surface is important for removal of MS-2 and PRD-1. Hydraulic loading rate also proved important in the removal of viruses. At the time of tracer test 2, columns dosed at the higher HLR (25 cm/day) had higher percent removals for both MS-2 and PRD-1. Soil type altered the removal of PRD-1 at the time of the second tracer test, at which time sandy loam had higher removal rates for PRD-1. No significant differences were observed between columns dosed four times daily and those dosed 24 times daily for either bacteriophage at either of the tracer test time points. These data suggest that over a relatively short period of operation the infiltrative surface of soil based wastewater treatment systems can achieve much higher

  19. Using acoustics to estimate inspiratory flow rate and drug removed from a dry powder inhaler.

    Science.gov (United States)

    Holmes, Martin S; Seheult, Jansen; Geraghty, Colm; D'Arcy, Shona; Costello, Richard W; Reilly, Richard B

    2013-01-01

    Morbidity and mortality rates of chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD) are rising. There is a strong requirement for more effective management of these chronic diseases. Dry powder inhalers (DPIs) are one kind of devices currently employed to deliver medication aimed at controlling asthma and COPD symptoms. Despite their proven effectiveness when used correctly, some patients are unable to reach the inspiratory flow rate required to remove medication from the breath actuated devices and as a result, the medication does not reach the airways. This study employs an acoustic recording device, attached to a common DPI to record the audio signals of simulated inhalations. A rotameter was used to measure the flow rate through the inhaler while a milligram weighing scale was used to measure the amount of drug removed from each simulated inhalation. It was found that a strong correlation existed (R(2)>0.96) when average power, median amplitude, root mean square and mean absolute deviation were used to predict peak inspiratory flow rate. At a flow of 30 L/Min (mean absolute deviation=0.0049), it was found that 77% of the total emitted dose was removed from the inhaler. Results indicate that acoustic measurements may be used in the prediction of inspiratory flow rate and quantity of medication removed from an inhaler.

  20. Vision-based Ground Test for Active Debris Removal

    Directory of Open Access Journals (Sweden)

    Seong-Min Lim

    2013-12-01

    Full Text Available Due to the continuous space development by mankind, the number of space objects including space debris in orbits around the Earth has increased, and accordingly, difficulties of space development and activities are expected in the near future. In this study, among the stages for space debris removal, the implementation of a vision-based approach technique for approaching space debris from a far-range rendezvous state to a proximity state, and the ground test performance results were described. For the vision-based object tracking, the CAM-shift algorithm with high speed and strong performance, and the Kalman filter were combined and utilized. For measuring the distance to a tracking object, a stereo camera was used. For the construction of a low-cost space environment simulation test bed, a sun simulator was used, and in the case of the platform for approaching, a two-dimensional mobile robot was used. The tracking status was examined while changing the position of the sun simulator, and the results indicated that the CAM-shift showed a tracking rate of about 87% and the relative distance could be measured down to 0.9 m. In addition, considerations for future space environment simulation tests were proposed.

  1. Comparing fixation used for calcaneal displacement osteotomies: a look at removal rates and cost.

    Science.gov (United States)

    Lucas, Douglas E; Simpson, G Alex; Philbin, Terrence M

    2015-02-01

    The calcaneal displacement osteotomy is a procedure frequently used by foot and ankle surgeons for hindfoot angular deformity. Traditional techniques use compression screw fixation that can result in prominent hardware. While the results of the procedure are generally good, a common concern is the development of plantar heel pain related to prominent hardware. The primary purpose of this study is to retrospectively compare clinical outcomes of 2 fixation methods for the osteotomy. Secondarily a cost analysis will compare implant costs to hardware removal costs. Records were reviewed for patients who had undergone a calcaneal displacement osteotomy fixated with either lag screw or a locked lateral compression plate (LLCP). Neuropathy, previous ipsilateral calcaneus surgery, heel pad trauma, or incomplete radiographic follow-up were exclusionary. Thirty-two patients (19.4%) required hardware removal from the screw fixation group compared to 1 (1.6%) of the LLCP group, which is significant (P cost was remarkably different with screw fixation costing on average $247.12, compared to the LLCP costing $1175.59. Although the LLCP cost was significantly higher, cost savings were identified when the cost of removal and removal rates were included. This study demonstrates that this device provides adequate stabilization for healing in equivalent time to screw fixation. The LLCP required decreased rates of hardware removal with fewer postoperative visits over a shorter period of time. Significant savings were demonstrated in the LLCP group despite the higher implant cost. Therapeutic, Level III, Retrospective Comparative Study. © 2014 The Author(s).

  2. Efficient Total Nitrogen Removal in an Ammonia Gas Biofilter through High-Rate OLAND

    DEFF Research Database (Denmark)

    De Clippeleir, Haydée; Courtens, Emilie; Mosquera, Mariela

    2012-01-01

    .86 ± 0.04 kg N m–3 biofilter d–1 and an empty bed residence time of 14 s. After 45 days of operation a stable nitrogen removal rate of 0.67 ± 0.06 kg N m–3 biofilter d–1, an ammonia removal efficiency of 99%, a removal of 75–80% of the total nitrogen, and negligible NO/N2O productions were obtained......Ammonia gas is conventionally treated in nitrifying biofilters; however, addition of organic carbon to perform post-denitrification is required to obtain total nitrogen removal. Oxygen-limited autotrophic nitrification/denitrification (OLAND), applied in full-scale for wastewater treatment, can...... at water flow rates of 1.3 ± 0.4 m3 m–2 biofilter section d–1. Profile measurements revealed that 91% of the total nitrogen activity was taking place in the top 36% of the filter. This study demonstrated for the first time highly effective and sustainable autotrophic ammonia removal in a gas biofilter...

  3. Study on Relationship between Seasonal Temperatures and Municipal Wastewater Pollutant Concentration and Removal Rate

    Directory of Open Access Journals (Sweden)

    Yuan Shaoxiong

    2016-01-01

    Full Text Available In this study, the temperatures, pollutant concentrations and other indicators of municipal wastewater influent and effluent were tested for 7 months in 6 constructed wetland microcosms; the hydraulic retention time is 2 days. The results indicated that for both influent and effluent, there was a highly significant negative correlation (P<0.01 between the temperature and the pollutant concentrations, there was a significant difference (P<0.05 between seasonal temperatures, and the pollutant concentrations in summer and autumn were significantly different from those in winter (P<0.05. Furthermore, a regression analysis of pollutant concentration (y based on changes in water temperature (x in different seasons was performed. The analysis revealed that the relationship has the form ‘y = a -bx + cx2’, that under certain circumstances, pollutant concentrations can be calculated based on the temperature, and that the concentrations of NH4-N, Total Phosphorus (TP and Soluble Reactive Phosphorus (SRP had a significantly negative correlation with their removal rate (P < 0.01. However, seasonal temperature clearly did not have a direct impact on the pollutant concentration, and some studies have indicated that the different manners in which urban residents use water as the temperature changes may be the real reason that the pollutant concentrations of municipal wastewater vary with seasonal temperature. Furthermore, when designing and operating constructed wetlands, the impact of the changes in pollutant concentrations generated by seasonal temperature should be fully considered, dilution and other means should be taken to ensure purification.

  4. Comparison of the silicone oil removal rate between vitrectomy and manual syringe negative pressure approach.

    Science.gov (United States)

    Lin, Zhong; Wu, Rong Han; Zhou, Ye Hui

    2017-08-01

    The purpose of this study was to compare the silicone oil removal rate between vitrectomy and manual syringe negative pressure approach. Thirty-five silicone oil-filled eyes were enrolled and allocated for manual (n = 19) and vitrectomy (n = 16) removal approaches. For manual approach, a 10-ml syringe was connected to the 23-gauge cannula through a short section of blood transfusion tube. Removal was started after pulling and fixing the plunger to the end part. The syringe was pulled away immediately once the residual of silicone oil cannot be observed through the cornea. For vitrectomy approach, the only difference was the source of negative pressure, i.e., the blood transfusion tube was connected to the cannula directly to remove the silicone oil. Silicone oil removal rate was defined as the volume of silicone oil divided by the time taken for removal. The mean time taken for silicone oil removal was faster for manual approach than vitrectomy approach (4.13 ± 1.41 vs. 6.14 ± 1.49, p = 0.001). Furthermore, the silicone oil removal rate was larger for manual approach (1.42 ± 0.30 vs. 0.90 ± 0.16 ml/min, p < 0.001). No severe intraoperative or postoperative complications were noted for both approaches. The mean IOP at day 1 after surgery was significantly lower than that at baseline in both groups (manual group 10.2 ± 4.5 vs. 17.6 ± 5.9, p < 0.001, vitrectomy group 15.1 ± 7.5 vs. 8.3 ± 1.9, p < 0.002). All the eyes were recovered at 1 week after surgery. The best-corrected visual acuity (LogMar) at 1 month postoperatively improved compared to that preoperative for both approaches (manual group: 1.10 ± 0.62 vs. 1.47 ± 0.76, p = 0.07; vitrectomy group: 1.10 ± 0.47 vs. 1.11 ± 0.50, p = 0.62). Both approaches are safe for silicone oil removal. The manual approach is more convenient and efficient.

  5. Evaluating of arsenic(V) removal from water by weak-base anion exchange adsorbents.

    Science.gov (United States)

    Awual, M Rabiul; Hossain, M Amran; Shenashen, M A; Yaita, Tsuyoshi; Suzuki, Shinichi; Jyo, Akinori

    2013-01-01

    Arsenic contamination of groundwater has been called the largest mass poisoning calamity in human history and creates severe health problems. The effective adsorbents are imperative in response to the widespread removal of toxic arsenic exposure through drinking water. Evaluation of arsenic(V) removal from water by weak-base anion exchange adsorbents was studied in this paper, aiming at the determination of the effects of pH, competing anions, and feed flow rates to improvement on remediation. Two types of weak-base adsorbents were used to evaluate arsenic(V) removal efficiency both in batch and column approaches. Anion selectivity was determined by both adsorbents in batch method as equilibrium As(V) adsorption capacities. Column studies were performed in fixed-bed experiments using both adsorbent packed columns, and kinetic performance was dependent on the feed flow rate and competing anions. The weak-base adsorbents clarified that these are selective to arsenic(V) over competition of chloride, nitrate, and sulfate anions. The solution pH played an important role in arsenic(V) removal, and a higher pH can cause lower adsorption capacities. A low concentration level of arsenic(V) was also removed by these adsorbents even at a high flow rate of 250-350 h(-1). Adsorbed arsenic(V) was quantitatively eluted with 1 M HCl acid and regenerated into hydrochloride form simultaneously for the next adsorption operation after rinsing with water. The weak-base anion exchange adsorbents are to be an effective means to remove arsenic(V) from drinking water. The fast adsorption rate and the excellent adsorption capacity in the neutral pH range will render this removal technique attractive in practical use in chemical industry.

  6. Removal of Selected Organochlorine Compounds by Ozone-based Processes

    Directory of Open Access Journals (Sweden)

    K. Šimkovič

    2017-07-01

    Full Text Available The paper is focused on the possibility of using ozonation process combined with iron nanoparticles (nZVI – nano zero-valent iron to remove selected specific synthetic substances, such as hexachlorobutadiene, pentachlorobenzene, hexachlorobenzene, lindane and heptachlor. Experimental measurements were performed in order to evaluate the effectiveness of the removal of substances and their removal rates. Removal of pesticides was also monitored through calculated DOC (dissolved organic carbon as cumulative wastewater quality indicator. We investigated the effectiveness of 5 mL L–1 nZVI suspension (equal to 1 g Fe0 for the optimization of micropollutants removal from model water. Applications of 5 mL L–1 nZVI suspension and combined O3/nZVI processes have been shown as the most effective. Increasing concentrations of nZVI had almost no impact on the efficiency of the degradation process. Higher degradation efficiencies of γ-HCH were measured in O3/nZVI compared to the ozonation process. Degradation of pesticides HCLB, HCLBD and PCLB in all tested processes achieved efficiencies above 88 %.

  7. Optimization of graffiti removal on natural stone by means of high repetition rate UV laser

    Energy Technology Data Exchange (ETDEWEB)

    Fiorucci, M.P., E-mail: m.p.fiorucci@udc.es [Centro de Investigacións Tecnolóxicas, Universidade da Coruña, 15403 Ferrol (Spain); Dpto. Enxeñaría dos Recursos Naturais e Medio Ambiente, E.T.S.E. Minas, Universidade de Vigo, 36200 Vigo (Spain); López, A.J., E-mail: ana.xesus.lopez@udc.es [Centro de Investigacións Tecnolóxicas, Universidade da Coruña, 15403 Ferrol (Spain); Ramil, A., E-mail: alberto.ramil@udc.es [Centro de Investigacións Tecnolóxicas, Universidade da Coruña, 15403 Ferrol (Spain); Pozo, S., E-mail: ipozo@uvigo.es [Dpto. Enxeñaría dos Recursos Naturais e Medio Ambiente, E.T.S.E. Minas, Universidade de Vigo, 36200 Vigo (Spain); Rivas, T., E-mail: trivas@uvigo.es [Dpto. Enxeñaría dos Recursos Naturais e Medio Ambiente, E.T.S.E. Minas, Universidade de Vigo, 36200 Vigo (Spain)

    2013-08-01

    The use of laser for graffiti removal is a promising alternative to conventional cleaning methods, though irradiation parameters must be carefully selected in order to achieve the effective cleaning without damaging the substrate, especially when referring to natural stone. From a practical point of view, once a safe working window is selected, it is necessary to determine the irradiation conditions to remove large paint areas, with minimal time consumption. The aim of this paper is to present a systematic procedure to select the optimum parameters for graffiti removal by means of the 3rd harmonic of a high repetition rate nanosecond Nd:YVO{sub 4} laser. Ablation thresholds of four spray paint colors were determined and the effect of pulse repetition frequency, beam diameter and line scan separation was analyzed, obtaining a set of values which optimize the ablation process.

  8. Optimization of graffiti removal on natural stone by means of high repetition rate UV laser

    Science.gov (United States)

    Fiorucci, M. P.; López, A. J.; Ramil, A.; Pozo, S.; Rivas, T.

    2013-08-01

    The use of laser for graffiti removal is a promising alternative to conventional cleaning methods, though irradiation parameters must be carefully selected in order to achieve the effective cleaning without damaging the substrate, especially when referring to natural stone. From a practical point of view, once a safe working window is selected, it is necessary to determine the irradiation conditions to remove large paint areas, with minimal time consumption. The aim of this paper is to present a systematic procedure to select the optimum parameters for graffiti removal by means of the 3rd harmonic of a high repetition rate nanosecond Nd:YVO4 laser. Ablation thresholds of four spray paint colors were determined and the effect of pulse repetition frequency, beam diameter and line scan separation was analyzed, obtaining a set of values which optimize the ablation process.

  9. Ciprofloxacin removal during secondary domestic wastewater treatment in high rate algal ponds.

    Science.gov (United States)

    Hom-Diaz, Andrea; Norvill, Zane N; Blánquez, Paqui; Vicent, Teresa; Guieysse, Benoit

    2017-08-01

    This study investigated the removal of antibiotic ciprofloxacin during the treatment of real wastewater using high rate algal ponds (HRAP). When spiked at 2 mg/L into primary domestic wastewater, ciprofloxacin (CPX) was efficiently removed from laboratory scale photobioreactors continuously operated under various durations of artificial illumination and hydraulic residence times. Subsequent batch tests conducted with reactor microcosms showed CPX removal was mainly caused by photodegradation during daytime, and sorption to biomass during night time. These findings were confirmed during an experiment conducted in a 1000 L pilot HRAP operated outdoors, as well as during outdoor batch assays conducted using pilot HRAP microcosms. While these results highlight a potentially interesting treatment capacity in comparison to conventional biological treatment, further research must confirm these findings at relevant pollutant concentration (ng-μg/L) and determine the fate and potential toxicity of degradation products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Nutrient removal by the integrated use of high rate algal ponds and macrophyte systems in China.

    Science.gov (United States)

    Chen, P; Zhou, Q; Paing, J; Le, H; Picot, B

    2003-01-01

    High Rate Algal Ponds (HRAP) were operated at pilot scale to investigate the performance of HRAP under the temperate climate conditions of Shanghai, China. The results indicated that the HRAP gave good efficiency for nutrient removal, especially during summer. With a retention time of 4 or 8d according to the season, the annual average removal efficiencies for COD, NH4-N and PO4-P were 50%, 87% and 40%, respectively. The multi-factor linear models showed the relationships between nutrient removal efficiency and influencing factors. Using a macrophyte pond to separate algae from HRAP can achieve concentrations of COD, TP and TKN in the effluent at around 50 mg/L, 1.5 mg/L and 5 mg/L respectively.

  11. Dyes removal from textile wastewater using graphene based nanofiltration

    Science.gov (United States)

    Makertihartha, I. G. B. N.; Rizki, Z.; Zunita, M.; Dharmawijaya, P. T.

    2017-05-01

    Wastewater produced from textile industry is having more strict regulation. The major pollutant of wastewater from textile industry is Dyes. Dyes have several harsh properties i.e toxic, volatile, complexing easily with mineral ions that are dissolved in water (decreasing the amount of important mineral ions in water), and hard to disintegrate, therefore it must be removed from the waste stream. There are several methods and mechanisms to remove dyes such as chemical and physical sorption, evaporation, biological degradation, and photocatalytic system that can be applied to the waste stream. Membrane-based separation technology has been introduced in dyes removal treatment and is well known for its advantages (flexibility, mild operating condition, insensitive to toxic pollutant). Graphene and its derivatives are novel materials which have special properties due to its ultrathin layer and nanometer-size pores. Thus, the materials are very light yet strong. Moreover, it has low cost and easy to fabricate. Recently, the application of graphene and its derivatives in nanofiltration membrane processes is being widely explored. This review investigates the potentials of graphene based membrane in dyes removal processes. The operating conditions, dyes removal effectiveness, and the drawbacks of the process are the main focus in this paper.

  12. Effect of Electric Discharge Machining on Material Removal Rate and White Layer Composition

    Directory of Open Access Journals (Sweden)

    SHAHID MEHMOOD

    2017-01-01

    Full Text Available In this study the MRR (Material Removal Rate of the aerospace grade (2024 T6 aluminum alloy 2024 T6 has been determined with copper electrode and kerosene oil is used as dielectric liquid. Discharge energy is controlled by electric current while keeping Pulse-ON time and Pulse-OFF time as constant. The characteristics of the EDMed (Electric Discharge Machined surface are discussed. The sub-surface defect due to arcing has been explained. As the surface material of tool electrode and workpiece melts simultaneously and there are chances of the contamination of both surfaces by the contents of each other. Therefore, the EDS (Energy Dispersive Spectroscopy of the white layer and base material of the workpiece was performed by SEM (Scanning Electron Microscope at the discharge currents of 3, 6 and 12 amperes. It was conformed that the contamination of the surface of the workpiece material occurred by carbon, copper and oxygen contents. The quantitative analysis of these contents with respect to the discharge current has been presented in this paper.

  13. Mechanism of cadmium ion removal by base treated juniper fiber

    Science.gov (United States)

    Soo-Hong Min; J.K. Park; James S. Han; Eun Woo Shin

    2003-01-01

    Pinyon juniper, Juniperus Monosperma, is a small-diameter and underutilized (SDU) lignocellulosic material. Evaluated were efficacy of base-treated juniper fiber (BTJF) sample for cadmium (Cd 2+ ) sorption and the viability of juniper fiber as a sorbent for the removal of Cd 2+ from water. Fourier Transform Infrared Spectroscopy (FTIR) analysis indicated that...

  14. The effects of cervical mucus removal before Intrauterine Insemination (IUI in improving pregnancy rates infertile women

    Directory of Open Access Journals (Sweden)

    Ghasemi A

    2011-07-01

    Full Text Available "n 800x600 Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} Background: Intrauterine insemination (IUI is a less expensive and less invasive treatment in comparison with other assisted reproductive techniques, and it has been widely used for a variety of indications as well as in the treatment of couples with infertility. The outcome of IUI may be affected by numerous factors but in this study, we evaluated the effects of cervical mucus removal undertaken before IUI on clinical pregnancy rates."n"nMethods : In this randomized clinical trial study, all infertile women who were candidates for IUI and attended Shahid Akbar Abadi Hospital during 2009 and 2010 were recruited. The participants were randomly assigned into two groups. Cervical mucus was removed prior to IUI in patients in group A but in group B, a classic IUI was done without removing the cervical mucus. Pregnancy rates were assessed in the two groups by serum levels of β-HCG and detection of fetus in the uterus.  "n"nResults : 291 women including 143 in the classic IUI group and 148 in cervical mucus removal group completed the study. The pregnancy rates were 14.2% (21 pregnancies upon 148 cycles in the cervical mucus removal group and 7% (10 pregnancies upon 143 cycles in the control group (P=0.04, OR: 2.199; CI 95%: 0.997-4.85."n"nConclusion: The findings showed that cervical mucus removal could result in a two-fold increase in pregnancy rate in comparison with classic IUI. Thus, we suggest this practical and noninvasive method to improve pregnancy rate in these patients.

  15. High rate nitrogen removal by ANAMMOX internal circulation reactor (IC) for old landfill leachate treatment.

    Science.gov (United States)

    Phan, The Nhat; Van Truong, Thi Thanh; Ha, Nhu Biec; Nguyen, Phuoc Dan; Bui, Xuan Thanh; Dang, Bao Trong; Doan, Van Tuan; Park, Joonhong; Guo, Wenshan; Ngo, Huu Hao

    2017-06-01

    This study aimed to evaluate the performance of a high rate nitrogen removal lab-scale ANAMMOX reactor, namely Internal Circulation (IC) reactor, for old landfill leachate treatment. The reactor was operated with pre-treated leachate from a pilot Partial Nitritation Reactor (PNR) using a high nitrogen loading rate ranging from 2 to 10kgNm-3d-1. High rate removal of nitrogen (9.52±1.11kgNm-3d-1) was observed at an influent nitrogen concentration of 1500mgNL-1. The specific ANAMMOX activity was found to be 0.598±0.026gN2-NgVSS-1d-1. Analysis of ANAMMOX granules suggested that 0.5-1.0mm size granular sludge was the dominant group. The results of DNA analysis revealed that Candidatus Kueneniastuttgartiensis was the dominant species (37.45%) in the IC reactor, whereas other species like uncultured Bacteroidetes bacterium only constituted 5.37% in the system, but they were still responsible for removing recalcitrant organic matter. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. An extracorporeal carbon dioxide removal (ECCO2R) device operating at hemodialysis blood flow rates.

    Science.gov (United States)

    Jeffries, R Garrett; Lund, Laura; Frankowski, Brian; Federspiel, William J

    2017-09-06

    Extracorporeal carbon dioxide removal (ECCO2R) systems have gained clinical appeal as supplemental therapy in the treatment of acute and chronic respiratory injuries with low tidal volume or non-invasive ventilation. We have developed an ultra-low-flow ECCO2R device (ULFED) capable of operating at blood flows comparable to renal hemodialysis (250 mL/min). Comparable operating conditions allow use of minimally invasive dialysis cannulation strategies with potential for direct integration to existing dialysis circuitry. A carbon dioxide (CO2) removal device was fabricated with rotating impellers inside an annular hollow fiber membrane bundle to disrupt blood flow patterns and enhance gas exchange. In vitro gas exchange and hemolysis testing was conducted at hemodialysis blood flows (250 mL/min). In vitro carbon dioxide removal rates up to 75 mL/min were achieved in blood at normocapnia (pCO2 = 45 mmHg). In vitro hemolysis (including cannula and blood pump) was comparable to a Medtronic Minimax oxygenator control loop using a time-of-therapy normalized index of hemolysis (0.19 ± 0.04 g/100 min versus 0.12 ± 0.01 g/100 min, p = 0.169). In vitro performance suggests a new ultra-low-flow extracorporeal CO2 removal device could be utilized for safe and effective CO2 removal at hemodialysis flow rates using simplified and minimally invasive connection strategies.

  17. Harvesting costs and production rates for seed-tree removal in young-growth, mixed-conifer stands

    Science.gov (United States)

    Philip M. McDonald

    1969-01-01

    Ponderosa pine seed trees left from a previous cutting on the Challenge Experimental Forest, California, were removed in October 1963. Logging costs and production rates were compared with those for a seed-tree cutting on an area nearby. Production rates for seed-tree removal greatly exceeded those for the operation as a whole. Skidding production increased by 38...

  18. ECG Identification Based on Non-Fiducial Feature Extraction Using Window Removal Method

    Directory of Open Access Journals (Sweden)

    Woo-Hyuk Jung

    2017-11-01

    Full Text Available This study proposes electrocardiogram (ECG identification based on non-fiducial feature extraction using window removal method, nearest neighbor (NN, support vector machine (SVM, and linear discriminant analysis (LDA. In the pre-processing stage, Daubechies 4 is used to remove the baseline wander and noise of the original signal. In the feature extraction and selection stage, windows are set at a time interval of 5 s in the preprocessed signal, while autocorrelation, scaling, and discrete cosine transform (DCT are applied to extract and select features. Thereafter, the window removal method is applied to all of the generated windows to remove those that are unrecognizable. Lastly, in the classification stage, the NN, SVM, and LDA classifiers are used to perform individual identification. As a result, when the NN is used in the Normal Sinus Rhythm (NSR, PTB diagnostic, and QT database, the results indicate that the subject identification rates are 100%, 99.40% and 100%, while the window identification rates are 99.02%, 97.13% and 98.91%. When the SVM is used, all of the subject identification rates are 100%, while the window identification rates are 96.92%, 95.82% and 98.32%. When the LDA is used, all of the subject identification rates are 100%, while the window identification rates are 98.67%, 98.65% and 99.23%. The proposed method demonstrates good results with regard to data that not only includes normal signals, but also abnormal signals. In addition, the window removal method improves the individual identification accuracy by removing windows that cannot be recognized.

  19. Nutrient removal in wastewater treatment high rate algal ponds with carbon dioxide addition.

    Science.gov (United States)

    Park, J B K; Craggs, R J

    2011-01-01

    The influence of CO2 addition to high rate algal ponds (HRAPS) on nitrogen removal was investigated using two pilot-scale HRAPs operated with different hydraulic retention times (HRT: 4 and 8 days), and was compared to the nitrogen removal by the 8-day HRT pond before CO2 addition was installed. Nitrogen balances were calculated by partitioning total nitrogen into organic and inorganic nitrogen (NH4+-N and NO3--N), and by separation of the organic nitrogen into particulate (PON) and dissolved organic nitrogen (DON). PON was further divided into algal organic nitrogen (AON) and bacteria organic nitrogen (BON) to investigate nitrogen mass flow in the HRAPS. This research shows that the proportion of algae in the algal/bacterial biomass in the longer 8-day HRT HRAP8d (55.6%) was appreciably lower than that in the shorter 4-day HRT HRAP4d (80.5%) when CO2 was added to control the maximum pH to rates, indicating that the longer 8-day HRT in the summer was detrimental for two reasons: lower algal productivity and increased nitrogen loss through nitrification/denitrification. Overall nitrogen removal of approximately 60% in the HRAPS with CO2 addition was mainly achieved by algal assimilation followed by sedimentation in the settling unit.

  20. Wafer size effect on material removal rate in copper CMP process

    Energy Technology Data Exchange (ETDEWEB)

    Yuh, Minjong; Jang, Soocheon; Park, Inho; Jeong, Haedo [Pusan National University, Busan (Korea, Republic of)

    2017-06-15

    The semiconductor industry has employed the Chemical mechanical planarization (CMP) to enable surface topography control. Copper has been used to build interconnects because of its low-resistivity and high-electromigration. In this study, the effect of wafer size on the Material removal rate (MRR) in copper CMP process was investigated. CMP experiments were conducted using copper blanket wafers with diameter of 100, 150, 200 and 300 mm, while temperature and friction force were measured by infrared and piezoelectric sen-sors. The MRR increases with an increase in wafer size under the same process conditions. The wafer size increased the sliding distance of pad, resulting in an increase in the process temperature. This increased the process temperature, accelerating the chemical etching rate and the dynamic etch rate. The sliding distance of the pad was proportional to the square of the wafer radius; it may be used to predict CMP results and design a CMP machine.

  1. Nutrient removal and biofuel production in high rate algal pond using real municipal wastewater.

    Science.gov (United States)

    Kim, Byung-Hyuk; Kang, Zion; Ramanan, Rishiram; Choi, Jong-Eun; Cho, Dae-Hyun; Oh, Hee-Mock; Kim, Hee-Sik

    2014-08-01

    This study evaluated the growth and nutrient removal ability of an indigenous algal consortium on real untreated municipal wastewater in a high rate algal pond (HRAP). The HRAP was operated semicontinuously under different hydraulic retention times (HRT: 2, 4, 6, and 8 days). The average removal efficiencies of chemical oxygen demand, and total nitrogen and phosphate of real municipal wastewater were maintained at 85.44 ± 5.10%, 92.74 ± 5.82%, and 82.85 ± 8.63%, respectively, in 2 day HRT. Algae dominated the consortium and showed high settling efficiency (99%), and biomass and lipid productivity of 0.500 ± 0.03 g/l/day and 0.103 ± 0.0083 g/l/day (2 day HRT), respectively. Fatty acid methyl ester analysis revealed a predominance of palmitate (C16:0), palmitoleate (C16:1), linoleate (C18:2), and linolenate (C18:3). Microalgal diversity analyses determined the presence of Chlorella, Scenedesmus, and Stigeoclonium as the dominant microalgae. The algal consortium provides significant value not only in terms of energy savings and nutrient removal but also because of its bioenergy potential as indicated by the lipid content (20-23%) and FAME profiling.

  2. Better living through conifer removal: A demographic analysis of sage-grouse vital rates.

    Science.gov (United States)

    Severson, John P; Hagen, Christian A; Tack, Jason D; Maestas, Jeremy D; Naugle, David E; Forbes, James T; Reese, Kerry P

    2017-01-01

    Sagebrush (Artemisia spp.) obligate wildlife species such as the imperiled greater sage-grouse (Centrocercus urophasianus) face numerous threats including altered ecosystem processes that have led to conifer expansion into shrub-steppe. Conifer removal is accelerating despite a lack of empirical evidence on grouse population response. Using a before-after-control-impact design at the landscape scale, we evaluated effects of conifer removal on two important demographic parameters, annual survival of females and nest survival, by monitoring 219 female sage-grouse and 225 nests in the northern Great Basin from 2010 to 2014. Estimates from the best treatment models showed positive trends in the treatment area relative to the control area resulting in an increase of 6.6% annual female survival and 18.8% nest survival relative to the control area by 2014. Using stochastic simulations of our estimates and published demographics, we estimated a 25% increase in the population growth rate in the treatment area relative to the control area. This is the first study to link sage-grouse demographics with conifer removal and supports recommendations to actively manage conifer expansion for sage-grouse conservation. Sage-grouse have become a primary catalyst for conservation funding to address conifer expansion in the West, and these findings have important implications for other ecosystem services being generated on the wings of species conservation.

  3. Biological phosphorus removal during high-rate, low-temperature, anaerobic digestion of wastewater

    Directory of Open Access Journals (Sweden)

    Ciara eKeating

    2016-03-01

    Full Text Available We report, for the first time, extensive biologically-mediated phosphate removal from wastewater during high-rate anaerobic digestion (AD. A hybrid sludge bed/fixed-film (packed pumice stone reactor was employed for low-temperature (12°C anaerobic treatment of synthetic sewage wastewater. Successful phosphate removal from the wastewater (up to 78% of influent phosphate was observed, mediated by biofilms in the reactor. Scanning electron microscopy and energy dispersive X-ray analysis revealed the accumulation of elemental phosphorus (~2% within the sludge bed and fixed-film biofilms. 4’, 6-diamidino-2-phenylindole (DAPI staining indicated phosphorus accumulation was biological in nature and mediated through the formation of intracellular inorganic polyphosphate (polyP granules within these biofilms. DAPI staining further indicated that polyP accumulation was rarely associated with free cells. Efficient and consistent chemical oxygen demand (COD removal was recorded, throughout the 732-day trial, at applied organic loading rates between 0.4-1.5 kg COD m-3 d-1 and hydraulic retention times of 8-24 hours, while phosphate removal efficiency ranged from 28-78% on average per phase. Analysis of protein hydrolysis kinetics and the methanogenic activity profiles of the biomass revealed the development, at 12˚C, of active hydrolytic and methanogenic populations. Temporal microbial changes were monitored using Illumina Miseq analysis of bacterial and archaeal 16S rRNA gene sequences. The dominant bacterial phyla present in the biomass at the conclusion of the trial were the Proteobacteria and Firmicutes and the dominant archaeal genus was Methanosaeta. Trichococcus and Flavobacterium populations, previously associated with low temperature protein degradation, developed in the reactor biomass. The presence of previously characterised polyphosphate accumulating organisms (PAOs such as Rhodocyclus, Chromatiales, Actinobacter and Acinetobacter was

  4. Biological Phosphorus Removal During High-Rate, Low-Temperature, Anaerobic Digestion of Wastewater.

    Science.gov (United States)

    Keating, Ciara; Chin, Jason P; Hughes, Dermot; Manesiotis, Panagiotis; Cysneiros, Denise; Mahony, Therese; Smith, Cindy J; McGrath, John W; O'Flaherty, Vincent

    2016-01-01

    We report, for the first time, extensive biologically mediated phosphate removal from wastewater during high-rate anaerobic digestion (AD). A hybrid sludge bed/fixed-film (packed pumice stone) reactor was employed for low-temperature (12°C) anaerobic treatment of synthetic sewage wastewater. Successful phosphate removal from the wastewater (up to 78% of influent phosphate) was observed, mediated by biofilms in the reactor. Scanning electron microscopy and energy dispersive X-ray analysis revealed the accumulation of elemental phosphorus (∼2%) within the sludge bed and fixed-film biofilms. 4', 6-diamidino-2-phenylindole (DAPI) staining indicated phosphorus accumulation was biological in nature and mediated through the formation of intracellular inorganic polyphosphate (polyP) granules within these biofilms. DAPI staining further indicated that polyP accumulation was rarely associated with free cells. Efficient and consistent chemical oxygen demand (COD) removal was recorded, throughout the 732-day trial, at applied organic loading rates between 0.4 and 1.5 kg COD m(-3) d(-1) and hydraulic retention times of 8-24 h, while phosphate removal efficiency ranged from 28 to 78% on average per phase. Analysis of protein hydrolysis kinetics and the methanogenic activity profiles of the biomass revealed the development, at 12°C, of active hydrolytic and methanogenic populations. Temporal microbial changes were monitored using Illumina MiSeq analysis of bacterial and archaeal 16S rRNA gene sequences. The dominant bacterial phyla present in the biomass at the conclusion of the trial were the Proteobacteria and Firmicutes and the dominant archaeal genus was Methanosaeta. Trichococcus and Flavobacterium populations, previously associated with low temperature protein degradation, developed in the reactor biomass. The presence of previously characterized polyphosphate accumulating organisms (PAOs) such as Rhodocyclus, Chromatiales, Actinobacter, and Acinetobacter was recorded

  5. What is the hardware removal rate after anteroinferior plating of the clavicle? A retrospective cohort study.

    Science.gov (United States)

    Baltes, Thomas P A; Donders, Johanna C E; Kloen, Peter

    2017-10-01

    Plate position in the operative treatment of displaced midshaft clavicle fractures or nonunions is most often on the superior side. However, superior clavicular plating often results in complaints of plate prominence and local soft tissue irritation, necessitating hardware removal. We have used anteroinferior placement of the plate in the hope of increasing biomechanical stability and fixation and also of lowering complaints of plate prominence and soft tissue irritation. In this report, we set out to study the percentage of hardware removal in our group of patients treated with anteroinferior plating of the clavicle after long-term follow-up. In this retrospective review, we evaluated all patients who were surgically treated with anteroinferior plating for midshaft clavicle fracture, delayed union, or nonunion by the senior author between February 2003 and July 2015. Patients required a minimum age of 16 years at time of surgery and a follow-up of >12 months. Patients with malunion, plating on the superior aspect, or double plating were excluded. The medical records of 53 patients (54 fractures) were reviewed after a mean follow-up duration of 6.4 years (range, 1.1-13.1). The mean age at follow-up was 47.8 years (range, 20.4-80.7). All fractures and nonunions healed. In only 3 cases (5.6%), hardware removal was requested by the patient because of plate prominence. Anteroinferior plating of midshaft clavicle fractures, delayed unions, and nonunions resulted in low hardware removal rates in our cohort. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  6. Effect of the Polydispersity of RBCs on the Recovery Rate of RBCs during the Removal of CPAs

    Directory of Open Access Journals (Sweden)

    Heyuan Qiao

    2014-01-01

    Full Text Available In the process of removing cryoprotectants from cryopreserved blood, the theoretically optimal operating condition, which is based on the assumption that the distribution of red blood cells is uniform, is often used to reduce or even avoid the hypotonic damage to cells. However, due to the polydispersity of cells, the optimal condition is actually not reliable. In this study, based on the discrete concept developed in our previous work, the effect of the polydispersity on the recovery rate of cells in the dilution-filtration system was statistically investigated by assigning three random parameters, isotonic cell volume, cell surface area, and osmotically inactive cell volume, to cells in small units of blood. The results show that, due to the polydispersity, the real recovery rate deviates from the ideal value that is based on uniform distribution. The deviation significantly increases with the standard errors of cell parameters, and it can be also magnified by high cryoprotectant concentrations. Under the effect of polydispersity, the uniform distribution-based optimized blood or diluent flow rate is not perfect. In practice, one should adopt a more conservative blood or diluent flow rate so that the hypotonic damage to cells can be further reduced.

  7. Membrane-based removal of volatile methylsiloxanes from biogas

    Energy Technology Data Exchange (ETDEWEB)

    Ajhar, Marc

    2011-12-16

    This work investigates the removal of volatile methylsiloxanes (VMS) from biogas using dense, rubbery membranes. It consists of the following: a) thorough overview of already established and still developing siloxane removal technologies, b) detailed investigation of a viable sampling and analytical method, c) screening of different elastomers to identify siloxane-selective membrane materials, d) design of a suitable membrane structure, i.e. theoretical considerations about the thicknesses of the active separation layer and the porous support layer, e) assessment of the siloxane separation performance of a silicone membrane module using both synthetic gas under laboratory conditions and real landfill gas, f) comparison between the state-of-the-art technology (adsorption on activated carbon) and membrane-based processes. Suitable polymers for siloxane removal from biogas exist, however, they are not commercially available as membranes. Among the elastomers studied, Pebax registered 2533 is particularly promising. The use of a membrane made of this material could potentially become new state-of-the-art technology.

  8. Laser-based removal of irregularly shaped space debris

    Science.gov (United States)

    Scharring, Stefan; Wilken, Jascha; Eckel, Hans-Albert

    2017-01-01

    While the feasibility of laser space debris removal by high energy lasers has been shown in concept studies and laboratory proofs of principle, we address the question of the effectiveness and responsibility associated with this technique. The large variety of debris shapes poses a challenge for predicting amount and direction of the impulse imparted to the target. We present a numerical code that considers variation of fluence throughout the target surface with respect to the resulting local momentum coupling. Simple targets as well as an example for realistic space debris are investigated with respect to momentum generation. The predictability of the imparted momentum is analyzed in a Monte Carlo study. It was found that slight variations of the initial debris position and orientation may yield large differences of the modified trajectories. We identify highly cooperative targets, e.g., spheres, as well as targets that are strongly sensitive to orientation, e.g., plates, and exhibit a poor performance in laser debris removal. Despite limited predictability for the motion of a particular debris object, the laser-based approach appears to be suitable for space debris removal, albeit not with a deterministic but rather with a probabilistic treatment of the resulting trajectory modifications.

  9. Removing eye blink artefacts from EEG-A single-channel physiology-based method.

    Science.gov (United States)

    Zhang, Shenghuan; McIntosh, Julia; Shadli, Shabah M; Neo, Phoebe S-H; Huang, Zhiyi; McNaughton, Neil

    2017-11-01

    EEG signals are often contaminated with artefacts, particularly with large signals generated by eye blinks. Deletion of artefact can lose valuable data. Current methods of removing the eye blink component to leave residual EEG, such as blind source component removal, require multichannel recording, are computationally intensive, and can alter the original EEG signal. Here we describe a novel single-channel method using a model based on the ballistic physiological components of the eye blink. This removes the blink component, leaving uncontaminated EEG largely unchanged. Processing time allows its use in real-time applications such as neurofeedback training. Blink removal had a success rate of over 90% recovered variance of original EEG when removing synthesised eye blink components. Fronto-lateral sites were poorer (∼80%) than most other sites (92-96%), with poor fronto-polar results (67%). When compared with three popular independent component analysis (ICA) methods, our method was only slightly (1%) better at frontal midline sites but significantly (>20%) better at lateral sites with an overall advantage of ∼10%. With few recording channels and real-time processing, our method shows clear advantages over ICA for removing eye blinks. It should be particularly suited for use in portable brain-computer-interfaces and in neurofeedback training. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Phytoremediation of chlorpyrifos in aqueous system by riverine macrophyte, Acorus calamus: toxicity and removal rate.

    Science.gov (United States)

    Wang, Qinghai; Li, Cui; Zheng, Ruilun; Que, Xiaoe

    2016-08-01

    The potential of Acorus calamus to remove chlorpyrifos from water was assessed under laboratory conditions. Toxic effects of the insecticide in A. calamus were evaluated using pulse-amplitude modulated chlorophyll fluorescence techniques as well. At exposure concentrations above 8 mg L(-1), A. calamus showed obvious phytotoxic symptom with significant reduction in quantum efficiency of PSII (ΦPSII) and photochemical quenching coefficient (qP) in 20-day test; the inhibition of maximal quantum efficiency of PSII (Fv/Fm) was accompanied by a significant rise in initial chlorophyll fluorescence (Fo) within 15-day exposures. Fv/Fm and Fo recover to the normal level after 20-day exposure. The reduced removal rate to chlorpyrifos was observed with increase of initial chlorpyrifos concentrations. At application levels of 1, 2, and 4 mg L(-1), the disappearance rate of chlorpyrifos in the hydroponic system with plants was significantly greater than that without plants during the 20-day test periods. Chlorpyrifos was taken up from medium and transferred to above ground tissues by the plant and significant amounts of chlorpyrifos accumulated in plant tissues. The result indicated that A. calamus can promote the disappearance of chlorpyrifos from water and may be used for phytoremediation of water contaminated with a relatively low concentration of chlorpyrifos insecticide (<4 mg L(-1)).

  11. An Approach of Dynamic Object Removing for Indoor Mapping Based on UGV SLAM

    Directory of Open Access Journals (Sweden)

    Jian Tang

    2015-07-01

    Full Text Available The study of indoor mapping for Location Based Service (LBS becomes more and more popular in recent years. LiDAR SLAM based mapping method seems to be a promising indoor mapping solution. However, there are some dynamic objects such as pedestrians, indoor vehicles, etc. existing in the raw LiDAR range data. They have to be removal for mapping purpose. In this paper, a new approach of dynamic object removing called Likelihood Grid Voting (LGV is presented. It is a model free method and takes full advantage of the high scanning rate of LiDAR, which is moving at a relative low speed in indoor environment. In this method, a counting grid is allocated for recording the occupation of map position by laser scans. The lower counter value of this position can be recognized as dynamic objects and the point cloud will be removed from map. This work is a part of algorithms in our self- developed Unmanned Ground Vehicles (UGV simultaneous localization and Mapping (SLAM system- NAVIS. Field tests are carried in an indoor parking place with NAVIS to evaluate the effectiveness of the proposed method. The result shows that all the small size objects like pedestrians can be detected and removed quickly; large size of objects like cars can be detected and removed partly.

  12. Nitrous oxide production in intermittently aerated Partial Nitritation-Anammox reactor: oxic N2O production dominates and relates with ammonia removal rate

    DEFF Research Database (Denmark)

    Blum, Jan-Michael; Jensen, Marlene Mark; Smets, Barth F.

    2018-01-01

    to an effective control of accumulation of nitrogen intermediates. However, due to frequent changes of redox conditions under intermittent aeration regimes, nitrous oxide production and emissions are dynamic. In this study the production and emission dynamics of nitrous oxide in an intermittently aerated......-production rates were observed at ammonia removal rates below 5 mg NH3-N*gVSS−1*L−1, when the fraction of nitrous oxide produced was 0.011 ± 0.004% (per ammonia removed). Based on the nitrous oxide dynamics and correlations, reactor operation at relatively low nitrogen loadings (below 100 mg NH4+-N*L−1), ammonia...

  13. Safety and efficacy of low fluence, high repetition rate versus high fluence, low repetition rate 810-nm diode laser for axillary hair removal in Chinese women.

    Science.gov (United States)

    Li, Wenhai; Liu, Chengyi; Chen, Zhou; Cai, Lin; Zhou, Cheng; Xu, Qianxi; Li, Houmin; Zhang, Jianzhong

    2016-11-01

    High-fluence diode lasers with contact cooling have emerged as the gold standard to remove unwanted hair. Lowering the energy should result in less pain and could theoretically affect the efficacy of the therapy. To compare the safety and efficacy of a low fluence high repetition rate 810-nm diode laser to those of a high fluence, low repetition rate diode laser for permanent axillary hair removal in Chinese women. Ninety-two Chinese women received four axillae laser hair removal treatments at 4-week intervals using the low fluence, high repetition rate 810-nm diode laser in super hair removal (SHR) mode on one side and the high fluence, low repetition rate diode laser in hair removal (HR) mode on the other side. Hair counts were done at each follow-up visit and 6-month follow-up after the final laser treatment using a "Hi Quality Hair Analysis Program System"; the immediate pain score after each treatment session was recorded by a visual analog scale. The overall median reduction of hair was 90.2% with the 810-nm diode laser in SHR mode and 87% with the same laser in HR mode at 6-month follow-up. The median pain scores in SHR mode and in HR mode were 2.75 and 6.75, respectively. Low fluence, high repetition rate diode laser can efficiently remove unwanted hair but also significantly improve tolerability and reduce adverse events during the course of treatment.

  14. Comparison of rates of union and hardware removal between large and small cannulated screws for calcaneal osteotomy.

    Science.gov (United States)

    Sayres, Stephanie C; Gu, Yang; Kiernan, Samuel; DeSandis, Bridget Ann; Elliott, Andrew J; O'Malley, Martin J

    2015-01-01

    The calcaneal osteotomy is a common procedure to correct hindfoot malalignment. Reported union rates are high, utilizing fixation methods including staples, plates, and most commonly cannulated screws. We began our practice using 6.5 mm and 7.3 mm cannulated screws, but complaints of postoperative posterior heel pain led to hardware removal in many patients. A switch to smaller 4.5 mm cannulated screws resulted in fewer symptoms, thus we hypothesized that using a smaller screw would decrease screw removal while maintaining an equally high union rate. The records of patients who underwent a calcaneal osteotomy by 2 surgeons between January 1996 and April 2012 were retrospectively reviewed. The rates of hardware removal and union were compared between osteotomies held with two 7.3 mm, 6.5 mm, and 4.5 mm cannulated screws. There were 272 feet that met the inclusion criteria. The hardware removal rate for 130 osteotomies held with two 7.3 mm screws was 29.2% and the removal rate for 115 osteotomies held with 4.5 mm screws was 13.0%, which was significantly different (P hardware removal. There was no loss of position from the smaller screws and we feel that the 4.5mm cannulated screw provides sufficient compression and achieves a high rate of union equal to that of the larger screws. Level IV, retrospective case series. © The Author(s) 2014.

  15. Motion analysis and removal in intensity variation based OCT angiography.

    Science.gov (United States)

    Liu, Xuan; Kirby, Mitchell; Zhao, Feng

    2014-11-01

    In this work, we investigated how bulk motion degraded the quality of optical coherence tomography (OCT) angiography that was obtained through calculating interframe signal variation, i.e., interframe signal variation based optical coherence angiography (isvOCA). We demonstrated theoretically and experimentally that the spatial average of isvOCA signal had an explicit functional dependency on bulk motion. Our result suggested that the bulk motion could lead to an increased background in angiography image. Based on our motion analysis, we proposed to reduce image artifact induced by transient bulk motion in isvOCA through adaptive thresholding. The motion artifact reduced angiography was demonstrated in a 1.3μm spectral domain OCT system. We implemented signal processing using graphic processing unit for real-time imaging and conducted in vivo microvasculature imaging on human skin. Our results clearly showed that the adaptive thresholding method was highly effective in the motion artifact removal for OCT angiography.

  16. Factors affecting ozone removal rates in a simulated aircraft cabin environment

    DEFF Research Database (Denmark)

    Tamas, Gyöngyi; Weschler, Charles J.; Bako-Biro, Zsolt

    2006-01-01

    Ozone concentrations were measured concurrently inside a simulated aircraft cabin and in the airstream providing ventilation air to the cabin. Ozone decay rates were also measured after cessation of ozone injection into the supply airstream. By systematically varying the presence or absence...... present, the measured ratio of ozone's concentration in the cabin versus that outside the cabin was 0.15-0.21, smaller than levels reported in the literature. The results reinforce the conclusion that the optimal way to reduce people's exposure to both ozone and ozone oxidation products is to efficiently...... of people, soiled T-shirts, aircraft seats and a used HEPA filter, we have been able in the course of 24 experiments to isolate the contributions of these and other factors to the removal of ozone from the cabin air. In the case of this simulated aircraft, people were responsible for almost 60% of the ozone...

  17. Emission Rate of Particulate Matter and Its Removal Efficiency by Precipitators in Under-Fired Charbroiling Restaurants

    Directory of Open Access Journals (Sweden)

    Jun-Bok Lee

    2011-01-01

    Full Text Available In order to explore the potent role of meat cooking processes as the emission sources of particulate matter (PM, emission rates and the associated removal efficiency by precipitators were estimated based on the on-site measurements made at five under-fired charbroiling (UFC restaurants. The emission patterns of PM for these five restaurants were compared after having been sorted into the main meat types used for cooking: beef (B, chicken (C, intestines (I, and pork (P: two sites. The mass concentrations (μg m-3 of three PM fractions (PM2.5/PM10/TSP measured from these restaurants were 15,510/15,701/17,175 (C; 8,525/10,760/12,676 (B; 11,027/13,249/13,488 (P; and 22,409/22,412/22,414 (I. Emission factors (g kg-1 for those PM fractions were also estimated as 3.23/4.08/4.80 (B, 3.07/3.82/3.87 (P, 8.12/8.22/8.99 (C, and 6.59/6.59/6.59 (I. If the annual emission rate of PM10 is extrapolated by combining its emission factor, population, activity factor, etc., it is estimated as 500 ton year-1, which corresponds to 2.4% of the PM10 budget in Seoul, Korea. Removal efficiencies of PM10 via precipitators, such as an electrostatic precipitator (ESP, bag filter (BF, and the combination system (ESP + catalyst, installed in those UFC restaurants ranged between 54.76 and 98.98%. The removal efficiency of PM by this control system was the least effective for particles with <0.4 μm, although those in the range of 0.4–10 μm were the most effective.

  18. Base-rate sensitivity through implicit learning

    Science.gov (United States)

    Bohil, Corey J.

    2017-01-01

    Two experiments assessed the contributions of implicit and explicit learning to base-rate sensitivity. Using a factorial design that included both implicit and explicit learning disruptions, we tested the hypothesis that implicit learning underlies base-rate sensitivity from experience (and that explicit learning contributes comparatively little). Participants learned to classify two categories of simple stimuli (bar graph heights) presented in a 3:1 base-rate ratio. Participants learned either from “observational” training to disrupt implicit learning or “response” training which supports implicit learning. Category label feedback on each trial was followed either immediately or after a 2.5 second delay by onset of a working memory task intended to disrupt explicit reasoning about category membership feedback. Decision criterion values were significantly larger following response training, suggesting that implicit learning underlies base-rate sensitivity. Disrupting explicit processing had no effect on base-rate learning as long as implicit learning was supported. These results suggest base-rate sensitivity develops from experience primarily through implicit learning, consistent with separate learning systems accounts of categorization. PMID:28632779

  19. Pharmacokinetics and mechanisms of plasma removal of hemoglobin-based oxygen carriers.

    Science.gov (United States)

    Estep, Timothy N

    2015-06-01

    The circulatory persistence, distribution, and metabolism of hemoglobin-based oxygen carriers (HBOCs) is a major determinant of their safety and efficacy. In this communication, published data on the pharmacokinetics and routes of plasma elimination of HBOCs are summarized and evaluated. The circulating half-life of HBOCs is dose-dependent in both animals and humans. Half-life also increases with molecular weight in animals, at least up to the MDa range. The functional half-life of HBOCs is diminished by as much as 40% due to oxidation of the heme group relative to the overall rate of removal of hemoglobin (Hb) from plasma. Kidney excretion of HBOCs is greatly diminished compared to that of unmodified Hb, but the liver remains a primary site of catabolism. Both hepatocytes and Kupffer cells have been implicated in receptor-mediated HBOC uptake. Removal also occurs in the spleen and/or bone marrow and probably at dispersed sites in the endothelium as well. HBOCs extravasate into the lymph at a rate inversely proportional to their molecular weight and are taken up by monocyte/macrophage CD163 receptors, both as free Hb and in complexes with haptoglobin (Hp). The interactions with both Hp and the CD163 receptor are altered by Hb modification. However, monocyte/macrophage uptake may not be a quantitatively important route for the removal of clinically relevant doses of HBOCs. The relative contributions of different removal pathways have yet to be comprehensively determined, particularly in humans.

  20. Comparison of EDCs removal in full and pilot scale membrane bioreactor plants: Effect of flux rate on EDCs removal in short SRT.

    Science.gov (United States)

    Komesli, O T; Muz, M; Ak, M S; Bakırdere, S; Gökçay, C F

    2017-12-01

    Currently, it is estimated that over 1 billion people are short of adequate portable water and this is expected to increase to 2.5 billion in the year 2025. Membrane Bioreactors (MBR) are now accepted as important tools to extend the availability of water by facilitating the reuse of wastewaters. Sludge Retention Time (SRT) and liquid flux rate are the two most important parameters for controlling the MBR process. In this study, the removal of selected endocrine disrupter compounds (EDCs), diltiazem, progesterone, estrone (E1), carbamazepine (Cbz) and acetaminophen (Acet), by one full scale (VRM) and one pilot scale (clear-box) MBR plants was investigated. During the study, sludge age was set at 10 days and the sludge concentration was fixed at about 5.0 g/L. The transmembrane pressure (TMP) got higher with either increasing flux or sludge concentration in the membrane chamber. Therefore, changing the flux from 13 to 30 L/m2-h in both plants caused enhancement in TMP from -25 to -300 mbar in the clear-box and from -160 to over -350 in the full scale MBRs. It was understood that flux had very little effect on the removal of EDCs at very low concentrations. Moreover, diltiazem was completely removed in the full scale whereas no removal was achieved in the pilot scale. Estrone and progesterone were completely removed by biodegradation in both plants. Acetaminophen was completely removed in the full scale plant whereas over 95% removal was achieved in the pilot scale MBR. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Weighted Nuclear Norm Minimization Based Tongue Specular Reflection Removal

    Directory of Open Access Journals (Sweden)

    Zhenchao Cui

    2015-01-01

    Full Text Available In computational tongue diagnosis, specular reflection is generally inevitable in tongue image acquisition, which has adverse impact on the feature extraction and tends to degrade the diagnosis performance. In this paper, we proposed a two-stage (i.e., the detection and inpainting pipeline approach to address this issue: (i by considering both highlight reflection and subreflection areas, a superpixel-based segmentation method was adopted for the detection of the specular reflection areas; (ii by extending the weighted nuclear norm minimization (WNNM model, a nonlocal inpainting method is proposed for specular reflection removal. Experimental results on synthetic and real images show that the proposed method is accurate in detecting the specular reflection areas and is effective in restoring tongue image with more natural texture information of tongue body.

  2. Adsorbent for p-phenylenediamine adsorption and removal based on graphene oxide functionalized with magnetic cyclodextrin

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Dongxue; Liu, Liangliang; Jiang, Xinyu; Yu, Jingang [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Chen, Xiaohong [Collaborative Innovation Center of Resource-conserving & Environment-friendly Society and Ecological Civilization, Changsha, 410083 (China); Chen, Xiaoqing, E-mail: xqchen@csu.edu.cn [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Collaborative Innovation Center of Resource-conserving & Environment-friendly Society and Ecological Civilization, Changsha, 410083 (China)

    2015-02-28

    Highlights: • Magnetic β-cyclodextrin-graphene oxide (MCG) show high adsorption capacity. • The maximum adsorption capacity was 1102.58 mg/g at 45 °C and pH 8. • MCG can be easily and fast extracted from water by magnetic attraction. • Removal rate of MCG could reach 98% after three times of adsorption. • Adsorption capacity of MCG remained at 81% after five cycles. - Abstract: Recently, graphene oxide (GO) based magnetic nanocomposites have been widely used in an adsorption-based process for the removal of organic pollutants from the water system. In this study, magnetic β-cyclodextrin-graphene oxide nanocomposites (MCG) were synthesized according to covalent binding of magnetic β-cyclodextrin nanoparticles onto the GO surface and the as-made nanocomposites were successfully applied as adsorbents for the adsorption and removal of p-phenylenediamines (PPD). The composition and morphology of prepared materials were characterized by Fourier infrared spectrometry (FT-IR), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). Effects of pH, temperature, time and reusability on the adsorption of PPD were investigated, as well as the kinetics and isotherms parameters of the adsorbents were determined. The results indicated that the maximum adsorption capacity of MCG was 1102.58 mg/g at 45 °C and pH 8. The adsorption capacity remained at 81% after five cycles. Removal rate could reach 98% after three times of adsorption. The adsorption process with PPD was found that fitted pseudo-second-order kinetics equations and the Langmuir adsorption model. The results showed the MCG had a good adsorption ability to remove organic pollutants in wastewater.

  3. Slag-Based Nanomaterial in the Removal of Hexavalent Chromium

    Science.gov (United States)

    Baalamurugan, J.; Ganesh Kumar, V.; Govindaraju, K.; Naveen Prasad, B. S.; Bupesh Raja, V. K.; Padmapriya, R.

    Slag-based nanomaterial is a by-product obtained during steel production and has wide range of components in the form of oxides. In this study, Induction Furnace (IF) steel slag-based application in adsorption of hexavalent chromium is investigated. IF slag has mixture of oxides mainly Fe2O3 and Chromium (VI) a highly toxic pollutant leads to environmental pollution and causes problem to human health mainly, carcinogenetic diseases. Slag-based nanomaterial is characterized using High Resolution Scanning Electron Microscope (HR-SEM) in which the size was around 100nm and X-ray Fluorescence (XRF) spectroscopy. Further inductively coupled plasma mass spectroscopy and Fourier transform infrared spectroscopy were used for adsorption studies. Slag activation using NaOH (alkali activation) to the intent of surface hydroxyl (‑OH) group attachment will be a cost-effective process in the removal of hexavalent chromium. Cr(VI) ions are adsorbed on the surface of alkali activated slag material. The core-shell formation of Fe(II)/Fe(III)/Cr(VI) and the adsorption are investigated in detail in the present study.

  4. effect of turning parameters on metal removal and tool wear rates

    African Journals Online (AJOL)

    user

    The LARGER THE BETTER signal to noise (S/N) ratio based on the Taguchi technique was applied for ... corrosion resistance, fatigue strength, and aesthetics .... to-noise ratio. 7. Verification of the optimal design parameters through confirmation experiment. The Experimental outlay and variable sets for tool wear rate and ...

  5. 78 FR 79600 - Removal of Person From the Entity List Based on a Removal Request

    Science.gov (United States)

    2013-12-31

    ... estimate of 43.8 minutes for a manual or electronic submission. Total burden hours associated with the PRA... (APA), 5 U.S.C. 553(b)(3)(B), BIS finds good cause to waive requirements that this rule be subject to... assessing such removal requests. Section 553(d) of the APA generally provides that rules may not take effect...

  6. Decomposition Criterion-based Redundancy Removal in Mechanical Structures

    Directory of Open Access Journals (Sweden)

    A. N. Bozhko

    2014-01-01

    Full Text Available The most important design solutions of production engineering for the assembly operation are an assembly sequence and assembly chart. Both are closely linked with each other and therefore are recorded in the single process flow sheet that is an assembly chart.Capability for successive order assembling and splitting into assembly units depends on a set of the product design properties from which the main ones are position mechanical connections used to locate details within a product. An adequate mathematical model of the mechanical connections of technical system is a hyper graph. It allows us to give the correct description of the location relation of variable-locality.The analysis of the array of drawings shows that many designs contain redundant mechanical connections. The inequality is a criterion of redundancy, where |X| is the number of tops of the hyper graph (details, and |R| is the number of hyper edges (full assembly bases. Excess of mutual coordination is a harmful phenomenon which at designing stage exhibits as unsolvable dimension chains, while at the assembly stage it shows as relocation. Redundant connections should be removed from a design at the earliest design-for-manufacturing stages. Removal of connections generates mechanical structures with different assembly properties. The work offers some important criteria of generation of irredundant mechanical structures. The paper considers in detail a maximum decomposition criterion, which allows us to receive structures with the greatest capability to split into assembly units. It shows that such structures exhibit high flexibility in assembling and are adaptable to various specifications and production processes.

  7. Removal of Polyvinyl Alcohol Using Photoelectrochemical Oxidation Processes Based on Hydrogen Peroxide Electrogeneration

    Directory of Open Access Journals (Sweden)

    Kai-Yu Huang

    2013-01-01

    Full Text Available This study investigates the removal efficiency of PVA from aqueous solutions using UV irradiation in combination with the production of electrogenerated hydrogen peroxide (H2O2 at a polyacrylonitrile-based activated carbon fiber (ACF cathode. Three cathode materials (i.e., platinum, graphite, and ACF were fed with oxygen and used for the electrogeneration of H2O2. The amount of electrogenerated H2O2 produced using the ACF cathode was five times greater than that generated using the graphite cathode and nearly 24 times greater than that from platinum cathode. Several parameters were evaluated to characterize the H2O2 electrogeneration, such as current density, oxygen flow rate, solution pH, and the supporting electrolyte used. The optimum current density, oxygen flow rate, solution pH, and supporting electrolyte composition were found to be 10 mA cm−2, 500 cm3 min−1, pH 3, and Na2SO4, respectively. The PVA removal efficiencies were achieved under these conditions 3%, 16%, and 86% using UV, H2O2 electrogeneration, and UV/H2O2 electrogeneration, respectively. A UV light intensity of 0.6 mW cm−2 was found to produce optimal PVA removal efficiency in the present study. A simple kinetic model was proposed which confirmed pseudo-first-order reaction. Reaction rate constant (kap was found to depend on the UV light intensity.

  8. Periodic venting of MABR lumen allows high removal rates and high gas-transfer efficiencies.

    Science.gov (United States)

    Perez-Calleja, P; Aybar, M; Picioreanu, C; Esteban-Garcia, A L; Martin, K J; Nerenberg, R

    2017-09-15

    The membrane-aerated biofilm reactor (MABR) is a novel treatment technology that employs gas-supplying membranes to deliver oxygen directly to a biofilm growing on the membrane surface. When operated with closed-end membranes, the MABR provides 100-percent oxygen transfer efficiencies (OTE), resulting in significant energy savings. However, closed-end MABRs are more sensitive to back-diffusion of inert gases, such as nitrogen. Back-diffusion reduces the average oxygen transfer rates (OTR), consequently decreasing the average contaminant removal fluxes (J). We hypothesized that venting the membrane lumen periodically would increase the OTR and J. Using an experimental flow cell and mathematical modeling, we showed that back-diffusion gas profiles developed over relatively long timescales. Thus, very short ventings could re-establish uniform gas profiles for relatively long time periods. Using modeling, we systematically explored the effect of the venting interval (time between ventings). At moderate venting intervals, opening the membrane for 20 s every 30 min, the venting significantly increased the average OTR and J without substantially impacting the OTEs. When the interval was short enough, in this case shorter than 20 min, the OTR was actually higher than for continuous open-end operation. Our results show that periodic venting is a promising strategy to combine the advantages of open-end and closed end operation, maximizing both the OTR and OTE. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Visual sensor based abnormal event detection with moving shadow removal in home healthcare applications.

    Science.gov (United States)

    Lee, Young-Sook; Chung, Wan-Young

    2012-01-01

    Vision-based abnormal event detection for home healthcare systems can be greatly improved using visual sensor-based techniques able to detect, track and recognize objects in the scene. However, in moving object detection and tracking processes, moving cast shadows can be misclassified as part of objects or moving objects. Shadow removal is an essential step for developing video surveillance systems. The goal of the primary is to design novel computer vision techniques that can extract objects more accurately and discriminate between abnormal and normal activities. To improve the accuracy of object detection and tracking, our proposed shadow removal algorithm is employed. Abnormal event detection based on visual sensor by using shape features variation and 3-D trajectory is presented to overcome the low fall detection rate. The experimental results showed that the success rate of detecting abnormal events was 97% with a false positive rate of 2%. Our proposed algorithm can allow distinguishing diverse fall activities such as forward falls, backward falls, and falling asides from normal activities.

  10. Visual Sensor Based Abnormal Event Detection with Moving Shadow Removal in Home Healthcare Applications

    Directory of Open Access Journals (Sweden)

    Young-Sook Lee

    2012-01-01

    Full Text Available Vision-based abnormal event detection for home healthcare systems can be greatly improved using visual sensor-based techniques able to detect, track and recognize objects in the scene. However, in moving object detection and tracking processes, moving cast shadows can be misclassified as part of objects or moving objects. Shadow removal is an essential step for developing video surveillance systems. The goal of the primary is to design novel computer vision techniques that can extract objects more accurately and discriminate between abnormal and normal activities. To improve the accuracy of object detection and tracking, our proposed shadow removal algorithm is employed. Abnormal event detection based on visual sensor by using shape features variation and 3-D trajectory is presented to overcome the low fall detection rate. The experimental results showed that the success rate of detecting abnormal events was 97% with a false positive rate of 2%. Our proposed algorithm can allow distinguishing diverse fall activities such as forward falls, backward falls, and falling asides from normal activities.

  11. Comparison of sand-based water filters for point-of-use arsenic removal in China.

    Science.gov (United States)

    Smith, Kate; Li, Zhenyu; Chen, Bohan; Liang, Honggang; Zhang, Xinyi; Xu, Ruifei; Li, Zhilin; Dai, Huanfang; Wei, Caijie; Liu, Shuming

    2017-02-01

    Contamination of groundwater wells by arsenic is a major problem in China. This study compared arsenic removal efficiency of five sand-based point-of-use filters with the aim of selecting the most effective filter for use in a village in Shanxi province, where the main groundwater source had arsenic concentration >200 μg/L. A biosand filter, two arsenic biosand filters, a SONO-style filter and a version of the biosand filter with nails embedded in the sand were tested. The biosand filter with embedded nails was the most consistent and effective under the study conditions, likely due to increased contact time between water and nails and sustained corrosion. Effluent arsenic was below China's standard of 50 μg/L for more than six months after construction. The removal rate averaged 92% and was never below 86%. In comparison, arsenic removal for the nail-free biosand filter was never higher than 53% and declined with time. The arsenic biosand filter, in which nails sit in a diffuser basin above the sand, performed better but effluent arsenic almost always exceeded the standard. This highlights the positive impact on arsenic removal of embedding nails within the top layer of biosand filter sand and the promise of this low-cost filtration method for rural areas affected by arsenic contamination. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. A new approach using coagulation rate constant for evaluation of turbidity removal

    Science.gov (United States)

    Al-Sameraiy, Mukheled

    2017-06-01

    Coagulation-flocculation-sedimentation processes for treating three levels of bentonite synthetic turbid water using date seeds (DS) and alum (A) coagulants were investigated in the previous research work. In the current research, the same experimental results were used to adopt a new approach on a basis of using coagulation rate constant as an investigating parameter to identify optimum doses of these coagulants. Moreover, the performance of these coagulants to meet (WHO) turbidity standard was assessed by introducing a new evaluating criterion in terms of critical coagulation rate constant (kc). Coagulation rate constants (k2) were mathematically calculated in second order form of coagulation process for each coagulant. The maximum (k2) values corresponded to doses, which were obviously to be considered as optimum doses. The proposed criterion to assess the performance of coagulation process of these coagulants was based on the mathematical representation of (WHO) turbidity guidelines in second order form of coagulation process stated that (k2) for each coagulant should be ≥ (kc) for each level of synthetic turbid water. For all tested turbid water, DS coagulant could not satisfy it. While, A coagulant could satisfy it. The results obtained in the present research are exactly in agreement with the previous published results in terms of finding optimum doses for each coagulant and assessing their performances. On the whole, it is recommended considering coagulation rate constant to be a new approach as an indicator for investigating optimum doses and critical coagulation rate constant to be a new evaluating criterion to assess coagulants' performance.

  13. Modeling nitrogen removal with partial nitritation and anammox in one floc-based sequencing batch reactor.

    Science.gov (United States)

    Ni, Bing-Jie; Joss, Adriano; Yuan, Zhiguo

    2014-12-15

    Full-scale application of partial nitritation and anammox in a single floc-based sequencing batch reactor (SBR) has been achieved for high-rate nitrogen (N) removal, but mechanisms resulting in reliable operation are not well understood. In this work, a mathematical model was calibrated and validated to evaluate operating conditions that lead to out-competition of nitrite oxidizers (NOB) from the SBRs and allow to maintain high anammox activity during long-term operation. The validity of the model was tested using experimental data from two independent previously reported floc-based full-scale SBRs for N-removal via partial nitritation and anammox, with different aeration strategies at aeration phase (continuous vs. intermittent aeration). The model described the SBR cycle profiles and long-term dynamic data from the two SBR plants sufficiently and provided insights into the dynamics of microbial population fractions and N-removal performance. Ammonium oxidation and anammox reaction could occur simultaneously at DO range of 0.15-0.3 mg O2 L(-1) at aeration phase under continuous aeration condition, allowing simplified process control compared to intermittent aeration. The oxygen supply beyond prompt depletion by ammonium oxidizers (AOB) would lead to the growth of NOB competing with anammox for nitrite. NOB could also be washed out of the system and high anammox fractions could be maintained by controlling sludge age higher than 40 days and DO at around 0.2 mg O2 L(-1). Furthermore, the results suggest that N-removal in SBR occurs via both alternating nitritation/anammox and simultaneous nitritation/anammox, supporting an alternative strategy to improve N-removal in this promising treatment process, i.e., different anaerobic phases can be implemented in the SBR-cycle configuration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. A study on the effect of feed rate and cutting speed on surface roughness and material removal rate of mild steel

    Science.gov (United States)

    Latif, A. A.; Ibrahim, M. R.; Amran, A. Z.; Rahim, E. A.

    2017-10-01

    In any machining process, achieving a good surface quality and maximization of material removal rate are absolute importance. This paper provides an insight to the effect of feed rate and cutting speed on NOVIANO and conventional cutting tool in term of surface roughness and Material Removal Rate (MRR). The output of the machining during slot milling of Mild Steel with 17 HRC were measured. Mitutoyo surface tester were used to measure average mean surface roughness (Ra) of the slot milling surface. For the MRR measurement, mathematical formula was used to calculate and evaluate the different weight of workpiece before and after milling. The result shows that, when the feed rate and cutting speed increase, better surface roughness and MRR will be occur. However, the comparison between both cutting tools found that the NOVIANO cutting tool produce much better result than conventional cutting tool where surface roughness and MRR is 13.97% and 51.62%.

  15. Behavior of nitrogen removal in an aerobic sponge based moving bed biofilm reactor.

    Science.gov (United States)

    Zhang, Xinbo; Song, Zi; Guo, Wenshan; Lu, Yanmin; Qi, Li; Wen, Haitao; Ngo, Huu Hao

    2017-08-19

    This study aims to investigate the behavior of nitrogen removal in an aerobic sponge based moving bed biofilm reactor by evaluating nitrification and denitrification rates of sponge biocarriers from three aerobic moving bed biofilm reactors (MBBRs) with filling ratios of 10% (R-10), 20% (R-20) and 30% (R-30). Results showed that the highest removal efficiencies of total nitrogen in three reactors were 84.5% (R-10), 93.6% (R-20) and 95.3% (R-30). Correspondingly, simultaneous nitrification and denitrification rate (SND) was 90.9%, 97.6% and 100%, respectively. Although R-20 had the highest attached-growth biomass (AGB) per gram of sponge compared to the other two reactors, R-30 showed the maximum ammonium oxidation rate (AOR) (2.1826±0.0717mgNH4(+)-N/gAGB/h) and denitrification rate (DNR) (5.0852±0.0891mgNO3(-)-N/gAGB/h), followed by R-20 and R-10. These results indicated AOR, DNR and AGB were affected by the filling ratio under the same operation mode. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Pilot-scale evaluation of anammox-based mainstream nitrogen removal from municipal wastewater.

    Science.gov (United States)

    Lotti, T; Kleerebezem, R; Hu, Z; Kartal, B; de Kreuk, M K; van Erp Taalman Kip, C; Kruit, J; Hendrickx, T L G; van Loosdrecht, M C M

    2015-01-01

    Autotrophic nitrogen removal in the mainstream wastewater treatment process is suggested to be a prerequisite of energy autarkic wastewater treatment plants (WWTP). Whilst the application of anammox-related technologies in the side-stream is at present state of the art, the feasibility of this energy-efficient process at mainstream conditions is still under development. Lower operating temperature and ammonium concentration, together with required high nitrogen removal efficiency, represent the main challenges to face in order to reach this appealing new frontier of the wastewater treatment field. In this study, we report the evaluation of the process in a plug-flow granular sludge-based pilot-scale reactor (4 m3) continuously fed with the actual effluent of the A-stage of the WWTP of Dokhaven, Rotterdam. The one-stage partial nitritation-anammox system was operated for more than 10 months at 19±1°C. Observed average N-removal and ammonium conversion rates were comparable or higher than those of conventional N-removal systems, with 182±46 and 315±33 mg-N L(-1) d(-1), respectively. Biochemical oxygen demand was also oxidized in the system with an average removal efficiency of 90%. Heterotrophic biomass grew preferentially in flocs and was efficiently washed out of the system. Throughout the experimentation, the main bottleneck was the nitritation process that resulted in nitrite-limiting conditions for the anammox conversion. Anammox bacteria were able to grow under mainstream WWTP conditions and new granules were formed and efficiently retained in the system.

  17. REMOVAL OF CRYPTOSPORIDIUM BY IN-LINE FILTRATION: EFFECTS OF COAGULANT TYPE, FILTER LOADING RATE AND TEMPERATURE

    Science.gov (United States)

    Eight pilot-scale runs were performed to evaluate the impacts of temperature, coagulant type and filter loading rates on the removal of Cryptosporidium oocysts through in-line filtration. The study was set up as a 2(3) factorial design, which allowed investigation of all possible...

  18. Ablation rate, caries removal, and restoration using Nd:YAG and Er:YAG lasers and air abrasion

    Science.gov (United States)

    White, Joel M.

    1998-04-01

    This study evaluated the ablation rate in dentin and enamel of the Nd:YAG laser (1 - 2W, 10Hz) and the Er:YAG laser (1 - 2.5W, 10Hz), compared to the high-speed drill, low-speed drill and air abrasion (fine and extra-fine particle size). Subsequently, the effectiveness of caries removal and restoration in enamel of the Nd:YAG laser at the same powers and pulse repetition rate was compared to the high-speed drill, low-speed drill, and air abrasion. Enamel and dentin of 1mm thick mid-coronal sections from extracted third molars were ablated by Er:YAG laser ((lambda) equals 2.94 micrometer), Nd:YAG laser ((lambda) equals 1.06 micrometer) both with air/water spray, high-speed drill with 300 carbide bur, and low-speed drill with $1/4 round bur and air abrasions at 160 psi, with fine air abrasion at 50 micrometer and extra fine at 27 micrometer particle size. Removal (ablation) rate defined as dentin or enamel thickness divided by time required for perforation of the samples was determined for lasers, drills and air abrasion. Multifactor randomized ANOVA (p less than 0.05) considered removal rate as a function of treatment conditions. Removal Rate (micrometers per second) Enamel Dentin High-speed drill 273 +/- 47.34 493 +/- 1.73 Low-speed drill 0 42 +/- 14.25 Nd:YAG 2W 0 103 +/- 37 Er:YAG 2W 35 +/- 10 348 +/- 101 Air abrasion/fine 220 +/- 27 433 +/- 99 Air abrasion/extra fine 151 +/- 13 203 +/- 30 Er:YAG laser at 2W 10Hz ablated both enamel and dentin faster than the low-speed drill but slower than the high-speed drill, while the Nd:YAG laser at identical power and pulse rate did not ablate healthy enamel but was capable of removing dentin. To determine caries removal rate in enamel, extracted superficial carious molars (n equals 35) that included minimal explorer penetration and radiographic confirmation of caries extent were selected. Samples were randomly distributed into treatment groups: high-speed drill (HS), low-speed drill (LS), Nd:YAG laser (L), Nd:YAG with air

  19. Partial bioaugmentation to remove 3-chloroaniline slows bacterial species turnover rate in bioreactors.

    Science.gov (United States)

    Falk, Michael W; Seshan, Hari; Dosoretz, Carlos; Wuertz, Stefan

    2013-12-01

    Bioaugmentation is a potentially powerful tool to direct community structure and metabolic capacities in bioreactors. Yet the outcome of bioaugmentation studies is usually unpredictable and effects on microbial community dynamics are poorly understood. We asked the question whether bioaugmentation could prevent a diversity shift induced by a model toxin, 3-chloroaniline (3-CA), regardless of whether 3-CA was degraded. Four replicate membrane bioreactors (MBRs) operating in parallel were amended with Pseudomonas putida UWC3 (pWDL7::rfp), a strain that carries the upper pathway genes necessary for partial degradation of 3-CA on its plasmid. Two MBRs served as controls and two MBRs were exposed to 3-CA for 71 days. Despite the selective pressure imposed by 3-CA, there was little or no 3-CA removal and neither the 16S rRNA gene of the augmented strain UWC3 nor the plasmid pWDL7::rfp proliferated in any of the reactors. Yet both host strain and plasmid were maintained at reduced levels (~10(4) host strain cells ml(-1)) in all reactors compared to the initial inoculum (~10(7) cells ml(-1); 1% of active cells). Additionally, the microbial community dynamics were evaluated for each MBR via terminal restriction fragment length polymorphism (T-RFLP) analysis (n = 15 per reactor) that targeted a portion of the 16S rRNA gene. Analysis comprised of a suite of multivariate statistics coupled with a theoretical microbial ecological approach, 'Island Biogeography', using a bacterial species time relationship (STR), within each MBR. Control MBRs had a wider range in w values than the treatment MBRs, which is attributed to the lack of a toxin selecting for biota that can withstand its toxic nature. Bioaugmentation alone strongly slowed the bacterial species turnover rate (as revealed by very low w scaling components), compared to non-bioaugmented reactors from a previous study, but did not protect the microbial community from a diversity shift caused by the toxin. Nonmetric

  20. A biomaterial based approach for arsenic removal from water.

    Science.gov (United States)

    Al Rmalli, Shaban W; Harrington, Chris F; Ayub, Mohammed; Haris, Parvez I

    2005-04-01

    We demonstrate that the non-living, dried roots of the water hyacinth plant [Eichhornia crassipes(Mart.) Solms] can rapidly remove arsenic from water. Atomic absorption spectrometry was used to demonstrate that more than 93% of arsenite (As(iii)) and 95% of arsenate (As(v)) were removed from a solution containing 200 microg As l(-1) within 60 minutes of exposure to a powder produced from dried roots. No difference in removal efficiency was observed between the two oxidation states of As studied. The amount of arsenic remaining in solution was found to be less than 10 microg l(-1) which is the WHO guideline limit value for As in drinking water. The presence of arsenic in drinking water in a number of countries in the developing world has been found to be much higher than the WHO level, affecting the health of millions of people. In this paper, we show that a biomaterial produced from dried water hyacinth roots, a plant that is found in abundant supply in many parts of the world, can provide a simple, effective and yet cheap method for removing arsenic from contaminated water.

  1. Influence of liquid and gas flow rates on sulfuric acid mist removal from air by packed bed tower

    Directory of Open Access Journals (Sweden)

    Jafari Mohammad Javad

    2012-12-01

    Full Text Available Abstract The possible emission of sulfuric acid mists from a laboratory scale, counter-current packed bed tower operated with a caustic scrubbing solution was studied. Acid mists were applied through a local exhaust hood. The emissions from the packed bed tower were monitored in three different categories of gas flow rate as well as three liquid flow rates, while other influencing parameters were kept almost constant. Air sampling and sulfuric acid measurement were carried out iso-kinetically using USEPA method 8. The acid mists were measured by the barium-thorin titration method. According to the results when the gas flow rate increased from 10 L/s to 30 L/s, the average removal efficiency increased significantly (p 3, respectively. L/G of 2–3 was recommended for designing purposes of a packed tower for sulfuric acid mists and vapors removal from contaminated air stream.

  2. The application of Fe–Mn hydrous oxides based adsorbent for removing selenium species from water

    KAUST Repository

    Szlachta, Małgorzata

    2013-02-01

    In this study, the adsorptive removal of selenium(IV) and selenium(VI) from water by a newly developed ion exchange adsorbent, based on Fe(III) and Mn(III) hydrous oxides, was examined. This study was conducted to determine the influence of various operating parameters, such as initial anion concentration, contact time, adsorbent dose, pH, solution temperature, and the presence of competitive anions, on the treatment performance. The high Se(IV) adsorptive capacity of the adsorbent (up to 41.02. mg/g at pH 4) was due to its high affinity for selenite, as reflected in the fast rate of uptake (batch studies) and an efficient long-term removal (column experiments). Although adsorption of anions traditionally decreases as pH increases, the mixed adsorbent was capable of purifying large volumes of Se(IV)-containing water (at pH 7) to reach concentrations lower than 10 μg/L, which meets the European Commission standards. The presence of sulphate and carbonate did not influence Se(IV) adsorption. However, high phosphate and silicate concentrations may have decreased the removal efficiency of Se(IV). Data from the batch and column adsorption experiments were fitted with a number of approved models, which revealed the adsorption mechanism and allowed for a comparison of the results. © 2012 Elsevier B.V.

  3. 75 FR 72965 - Federal Travel Regulation; Removal of Privately Owned Vehicle Rates; Privately Owned Automobile...

    Science.gov (United States)

    2010-11-29

    ... regarding Seating Upgrade Programs in coach-class; and corrects grammatical errors. Accordingly, this final... than that authorized by the agency. 3. Section 301-10.124--Correcting a grammatical error by removing... travel; and makes certain grammatical corrections, where applicable. DATES: Effective Date: This final...

  4. Bioelectrode-based approach for enhancing nitrate and nitrite removal and electricity generation from eutrophic lakes

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    for nitrogen removal from surface waters. In this study, a sediment-type MFC based on two pieces of bioelectrodes was employed as a novel in situ applicable approach for nitrogen removal, as well as electricity production from eutrophic lakes. Maximum power density of 42 and 36 mW/m2 were produced respectively...... from nitrate- and nitrite-rich synthetic lake waters at initial concentration of 10 mg-N/L. Along with the electricity production a total nitrogen removal of 62% and 77% was accomplished, for nitrate and nitrite, respectively. The nitrogen removal was almost 4 times higher under close-circuit condition...... oxygen (DO) level in the water and acetate level injected to the sediment. Excessive oxygen resulted in dramatically decrease of nitrogen removal efficiency and only 7.8% removal was obtained at DO level of 7.8 mg/l. The power generation and nitrogen removal increased with acetate level and was nearly...

  5. Bioelectrode-based approach for enhancing nitrate and nitrite removal and electricity generation from eutrophic lakes

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2012-01-01

    for nitrogen removal from surface waters. In this study, a sediment-type MFC based on two pieces of bioelectrodes was employed as a novel in situ applicable approach for nitrogen removal, as well as electricity production from eutrophic lakes. Maximum power density of 42 and 36 mW/m2 were produced respectively...... from nitrate- and nitrite-rich synthetic lake waters at initial concentration of 10 mg-N/L. Along with the electricity production a total nitrogen removal of 62% and 77% was accomplished, for nitrate and nitrite, respectively. The nitrogen removal was almost 4 times higher under close-circuit condition...... oxygen (DO) level in the water and acetate level injected to the sediment. Excessive oxygen resulted in dramatically decrease of nitrogen removal efficiency and only 7.8% removal was obtained at DO level of 7.8 mg/l. The power generation and nitrogen removal increased with acetate level and was nearly...

  6. Evaluation of ozone generation and indoor organic compounds removal by air cleaners based on chamber tests

    Science.gov (United States)

    Yu, Kuo-Pin; Lee, Grace Whei-May; Hsieh, Ching-Pei; Lin, Chi-Chi

    2011-01-01

    Ozone can cause many health problems, including exacerbation of asthma, throat irritation, cough, chest ache, shortness of breath, and respiratory infections. Air cleaners are one of the sources of indoor ozone, and thus the evaluation of ozone generated by air cleaners is desired significant issue. Most evaluation methods proposed are based on chamber tests. However, the adsorption and desorption of ozone on the wall of test chamber and the deposition of ozone resulted from the surface reaction can influence the evaluation results. In this study, we developed a mass balance model that took the adsorption, desorption and deposition of ozone into consideration to evaluate the effective ozone emission rates of six selected air cleaners. The experiments were conducted in a stainless steel chamber with a volume of 11.3 m 3 at 25 °C and 60% relative humidity. The adsorption, desorption and deposition rate constants of ozone obtained by fitting the model to the experimental data were k a = 0.149 ± 0.052 m h -1, k d = 0.013 ± 0.007 h -1, and k r = 0.050 ± 0.020 h -1, respectively. The effective ozone emission rates of Air Cleaners No. 1, 2, and 3 ranged between 13,400-24,500 μg h -1, 7190-10,400 μg h -1, and 4880-6560 μg h -1, respectively, which were more stable than those of No.4, 5, and 6. The effective ozone emission rates of Air Cleaners No. 4, 5, and 6 increased with the time of operation which might be relevant to the decrease of ozone removal by the "aging" filter installed in these cleaners. The removal of toluene and formaldehyde by these six air cleaners were also evaluated and the clean air delivery rates (CADRs) of these two pollutants ranged from non-detectable to 0.42 ± 0.08 m 3 h -1, and from non-detectable to 0.75 ± 0.07 m 3 h -1, respectively. The CADRs showed an insignificant relationship with the effective ozone emission rates. Thus, the removal of toluene and formaldehyde might be resulted from the adsorption on the filters and the

  7. Impact of influent wastewater quality on nitrogen removal rates in multistage treatment wetlands.

    Science.gov (United States)

    Gajewska, Magdalena; Jóźwiakowski, Krzysztof; Ghrabi, Ahmed; Masi, Fabio

    2015-09-01

    Nitrogen removal in treatment wetlands is influenced by many factors, and the presence of electron donors (biodegradable organic matter) and electron acceptors (nitrate ions) is the main limiting one; for obtaining these conditions, multistage treatment wetlands (MTWs) are required, where an extensive nitrification can be obtained in the first stages under aerobic conditions leaving then to the following anoxic/anaerobic stages the duty of the denitrification. Most of the biodegradable organic matter is however oxidised in the first stages, and therefore, the inlet to the denitrification beds is usually poor of easily degradable carbon sources. This study is comparing the long-term performances obtained at several MTWs operating in Europe (North and South) and North Africa in order to understand if there is a significant avail in making use of the influent chemical oxygen demand (COD)/N ratio during the design phase for ensuring proper performances in terms of N overall removal. The statistic analysis performed in this study have shown that MTWs are capable to ensure sufficient removal of both organic and nutrients even in unfavourable proportions of macronutrients (C and N). The usual assumptions for conventional biological treatment systems concerning adequate C/N ratios seem to be dubious in case of wastewater treatment in MTWs.

  8. Multiple Description Coding Based on Optimized Redundancy Removal for 3D Depth Map

    Directory of Open Access Journals (Sweden)

    Sen Han

    2016-06-01

    Full Text Available Multiple description (MD coding is a promising alternative for the robust transmission of information over error-prone channels. In 3D image technology, the depth map represents the distance between the camera and objects in the scene. Using the depth map combined with the existing multiview image, it can be efficient to synthesize images of any virtual viewpoint position, which can display more realistic 3D scenes. Differently from the conventional 2D texture image, the depth map contains a lot of spatial redundancy information, which is not necessary for view synthesis, but may result in the waste of compressed bits, especially when using MD coding for robust transmission. In this paper, we focus on the redundancy removal of MD coding based on the DCT (discrete cosine transform domain. In view of the characteristics of DCT coefficients, at the encoder, a Lagrange optimization approach is designed to determine the amounts of high frequency coefficients in the DCT domain to be removed. It is noted considering the low computing complexity that the entropy is adopted to estimate the bit rate in the optimization. Furthermore, at the decoder, adaptive zero-padding is applied to reconstruct the depth map when some information is lost. The experimental results have shown that compared to the corresponding scheme, the proposed method demonstrates better rate central and side distortion performance.

  9. Sorption Kinetics for the Removal of Cadmium and Zinc onto Palm Kernel Shell Based Activated Carbon

    Directory of Open Access Journals (Sweden)

    Muhammad Muhammad

    2010-12-01

    Full Text Available The kinetics and mechanism of cadmium and zinc adsorption on palm kernel shell based activated carbons (PKSAC have been studied. A series of batch laboratory studies were conducted in order to investigate the suitability of palm kernel shell based activated carbon (PKSAC for the removal of cadmium (cadmium ions and zinc (zinc ions from their aqueous solutions. All batch experiments were carried out at pH 7.0 and a constant temperature of 30+-1°C using an incubator shaker that operated at 150 rpm. The kinetics investigated includes the pseudo first order, the pseudo-second order and the intraparticle diffusion models. The pseudo-second order model correlate excellently the experimental data, suggesting that chemisorption processes could be the rate-limiting step. Keywords: adsorption, cadmium, kinetics, palm kernel shell, zinc

  10. HYBRID FILM -PRETREATED GALVANIZED STEEL OBTAINED BY DIP-COATING PROCESS: INFLUENCE OF THE REMOVAL RATE OF THE SOL

    OpenAIRE

    Sandra Kunst; José Matos; Leonardo Antonini; Gustavo Ludwig; Luciane Fuhr; Célia Malfatti

    2013-01-01

    In this study, galvanized steel was coated with a silane obtained from a sol consisting of silanes precursors 3 - (trimetoxisililpropil) methacrylate (Tmspma) and tetraethoxysilane (TEOS) with addition of cerium nitrate [0.01 M]. Different sol removal rate were employed (10, 20 and 30 cm.min-1). Characterization of the films was performed by Scanning Electron Microscopy (SEM), perfilometry, wetting angle, open circuit potential and potentiodynamic polarization and electrochemical impedance sp...

  11. Actual laser removal of black soiling crust from siliceous sandstone by high pulse repetition rate equipment: effects on surface morphology

    Directory of Open Access Journals (Sweden)

    Iglesias-Campos, M. A.

    2016-03-01

    Full Text Available This research project studies the role of pulse repetition rate in laser removal of black soiling crust from siliceous sandstone, and specifically, how laser fluence correlates with high pulse repetition rates in cleaning practice. The aim is to define practical cleaning processes and determine simple techniques for evaluation based on end-users’ perspective (restorers. Spot and surface tests were made using a Q-switched Nd:YAG laser system with a wide range of pulse repetition rates (5–200 Hz, systematically analysed and compared by macrophotography, portable microscope, stereomicroscope with 3D visualizing and area roughness measurements, SEM imaging and spectrophotometry. The results allow the conclusion that for operation under high pulse repetition rates the average of total energy applied per spot on a treated surface should be attendant upon fluence values in order to provide a systematic and accurate description of an actual laser cleaning intervention.En este trabajo se estudia el papel de la frecuencia de repetición en la limpieza láser de costras de contaminación sobre una arenisca silícea, y concretamente, como se relaciona fluencia y frecuencias elevadas en una limpieza real. Se pretende definir un procedimiento práctico de limpieza y determinar técnicas sencillas de evaluación desde el punto de vista de los usuarios finales (restauradores. Para el estudio se realizaron diferentes ensayos en spot y en superficie mediante un equipo Q-switched Nd:YAG con un amplio rango de frecuencias (5–200 Hz, que se analizaron y compararon sistemáticamente mediante macrofotografía, microscopio portátil, estereomicroscopio con visualización 3D y mediciones de rugosidad en área, imágenes SEM y espectrofotometría. Los resultados permiten proponer que, al trabajar con altas frecuencias, la media de la energía total depositada por spot en la superficie debería acompañar los valores de fluencia para describir y comprender mejor una

  12. Organocatalytic removal of formaldehyde adducts from RNA and DNA bases

    Science.gov (United States)

    Karmakar, Saswata; Harcourt, Emily M.; Hewings, David S.; Lovejoy, Alexander F.; Kurtz, David M.; Ehrenschwender, Thomas; Barandun, Luzi J.; Roost, Caroline; Alizadeh, Ash A.; Kool, Eric T.

    2015-09-01

    Formaldehyde is universally used to fix tissue specimens, where it forms hemiaminal and aminal adducts with biomolecules, hindering the ability to retrieve molecular information. Common methods for removing these adducts involve extended heating, which can cause extensive degradation of nucleic acids, particularly RNA. Here, we show that water-soluble bifunctional catalysts (anthranilates and phosphanilates) speed the reversal of formaldehyde adducts of mononucleotides over standard buffers. Studies with formaldehyde-treated RNA oligonucleotides show that the catalysts enhance adduct removal, restoring unmodified RNA at 37 °C even when extensively modified, while avoiding the high temperatures that promote RNA degradation. Experiments with formalin-fixed, paraffin-embedded cell samples show that the catalysis is compatible with common RNA extraction protocols, with detectable RNA yields increased by 1.5-2.4-fold using a catalyst under optimized conditions and by 7-25-fold compared with a commercial kit. Such catalytic strategies show promise for general use in reversing formaldehyde adducts in clinical specimens.

  13. Methylene blue removal by carbonized textile sludge-based adsorbent.

    Science.gov (United States)

    Rahman, Ari; Kishimoto, Naoyuki; Urabe, Takeo; Ikeda, Kazuki

    2017-12-01

    Colored effluent and a large amount of sludge are major pollutant sources derived from textile industry activity. In this research, the idea for converting textile sludge into a potential adsorbent was conducted through a carbonization process in order to solve the colored effluent problem. Textile sludge was carbonized at a temperature ranging from 400 to 800 °C in the absence of oxygen. Maximum adsorption capacity of carbonized sludge for methylene blue removal reached 60.30 mg/g when the sludge was carbonized at 600 °C with specific surface area of 138.9 m 2 /g and no significant alteration was observed until 800 °C. Experimental research by using a real wastewater also showed that there was almost no disruption during adsorption of methylene blue into surface of carbonized sludge. While reactivation process revealed that the regeneration of carbonized sludge was applicable by secondary heating at the same carbonization temperature. Furthermore, the application of this research demonstrated that the carbonized textile sludge was a good adsorbent for methylene blue removal and had a capability to be reactivated.

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

    DEFF Research Database (Denmark)

    Yin, Weizhao; Wu, Jinhua; Huang, Weilin

    2016-01-01

    Abstract This study investigated the effects of varying nitrobenzene (NB) loadings via increasing flow rate or influent NB concentration mode on the removal efficiency in zero-valent iron (ZVI) columns sterilized (abiotic) or preloaded with acclimated microorganisms (biotic). It was shown...... flow rates and influent NB concentrations were at 0.5 mL min− 1 and 80 μmol L− 1 for the abiotic column and 2.0 mL min-1 and 240 μmol L− 1 for the biotic column, respectively. This study indicated that microorganisms not only enhanced overall reduction of NB, but also facilitated NB sequestration...

  15. Response surface modelling of tool electrode wear rate and material removal rate in micro electrical discharge machining of Inconel 718

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2017-01-01

    Inconel 718 is a corrosion-resistant and high strength nickel-based alloy with wide range of applications includingcomponents for cryogenic tankage, liquid fueled rockets and casings for aircraft engines. The material is characterizedby high hardness, high temperature strength, low thermal...

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

    Science.gov (United States)

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

    2016-08-01

    This study investigated the effects of varying nitrobenzene (NB) loadings via increasing flow rate or influent NB concentration mode on the removal efficiency in zero-valent iron (ZVI) columns sterilized (abiotic) or preloaded with acclimated microorganisms (biotic). It was shown that physical sequestration via adsorption/co-precipitation and reductive transformation of NB to aniline (AN) were the two major mechanisms for the NB removal in both abiotic and biotic ZVI columns. The NB removal efficiency decreased in both columns as the flow rate increased from 0.25 to 1.0mLmin(-1) whereas the AN recovery increased accordingly, with relatively high AN recovery observed at the flow rate of 1.0mLmin(-1). At the constant flow rate of 0.5mLmin(-1), increasing influent NB concentration from 80 to 400μmolL(-1) resulted in decreasing of the overall NB removal efficiency from 79.5 to 48.6% in the abiotic column and from 85.6 to 62.5% in the biotic column. The results also showed that the sequestration capacity and chemical reduction capacity were respectively 72% and 157.6% higher in the biotic column than in the abiotic column at the same tested hydraulic conditions and NB loadings. The optimal flow rates and influent NB concentrations were at 0.5mLmin(-1) and 80μmolL(-1) for the abiotic column and 2.0mLmin-1 and 240μmolL(-1) for the biotic column, respectively. This study indicated that microorganisms not only enhanced overall reduction of NB, but also facilitated NB sequestration within the porous media and that the optimal loading conditions for overall removal, sequestration, and reduction of NB may be different. Optimal operation conditions should be found for preferred sequestration or transformation (or both) of the target contaminants to meet different goals of groundwater remediation with the ZVI-PRB systems. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Active Debris Removal System Based on Polyurethane Foam

    Science.gov (United States)

    Rizzitelli, Federico; Valdatta, Marcelo; Bellini, Niccolo; Candini Gian, Paolo; Rastelli, Davide; Romei, Fedrico; Locarini, Alfredo; Spadanuda, Antonio; Bagassi, Sara

    2013-08-01

    Space debris is an increasing problem. The exponential increase of satellite launches in the last 50 years has determined the problem of space debris especially in LEO. The remains of past missions are dangerous for both operative satellites and human activity in space. But not only: it has been shown that uncontrolled impacts between space objects can lead to a potentially dangerous situation for civil people on Earth. It is possible to reach a situation of instability where the big amount of debris could cause a cascade of collisions, the so called Kessler syndrome, resulting in the infeasibility of new space missions for many generations. Currently new technologies for the mitigation of space debris are under study: for what concerning the removal of debris the use of laser to give a little impulse to the object and push it in a graveyard orbit or to be destroyed in the atmosphere. Another solution is the use of a satellite to rendezvous with the space junk and then use a net to capture it and destroy it in the reentry phase. In a parallel way the research is addressed to the study of deorbiting solutions to prevent the formation of new space junk. The project presented in this paper faces the problem of how to deorbit an existing debris, applying the studies about the use of polyurethane foam developed by Space Robotic Group of University of Bologna. The research is started with the Redemption experiment part of last ESA Rexus program. The foam is composed by two liquid components that, once properly mixed, trig an expansive reaction leading to an increase of volume whose entity depends on the chemical composition of the two starting components. It is possible to perform two kind of mission: 1) Not controlled removal: the two components are designed to react producing a low density, high expanded, spongy foam that incorporates the debris. The A/m ratio of the debris is increased and in this way also the ballistic parameter. As a consequence, the effect of

  18. Removal rate and releases of polybrominated diphenyl ethers in two wastewater treatment plants, Korea

    Science.gov (United States)

    Lee, Hyo Jin; Kim, Gi Beum

    2017-06-01

    Wastewater treatment plants (WWTPs) play an important role in minimizing the release of many pollutants into the environment. Nineteen congeners in two WWTPs in Korea were determined to investigate the occurrence and fate of polybrominated diphenyl ethers (PBDEs) during wastewater treatment processes. The concentration of total PBDEs was 69.6 and 183 ng/L in influent, which declined to 1.59 and 2.34 ng/L in the final effluent, respectively (Tongyeong and Jinhae WWTPs). PBDEs were found to exist mostly in the particulate phase of wastewater, which rendered sedimentation efficient for the removal of PBDEs. BDE-209 was the predominant congener in the influent and sludge. Most of the PBDEs entering the WWTPs presumably ended up in the sludge, with organisms in soil exposed to PBDEs through the usage of sludge application to agricultural land was relatively low. To our knowledge, this study is the first to report on the removal efficiency of PBDEs in a WWTP in Korea.

  19. Biologically-based signal processing system applied to noise removal for signal extraction

    Science.gov (United States)

    Fu, Chi Yung; Petrich, Loren I.

    2004-07-13

    The method and system described herein use a biologically-based signal processing system for noise removal for signal extraction. A wavelet transform may be used in conjunction with a neural network to imitate a biological system. The neural network may be trained using ideal data derived from physical principles or noiseless signals to determine to remove noise from the signal.

  20. Removal of heavy metals from aqueous solution by adsorption on biomass based adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Sultan; Azmatullah, M. [Malakand Univ., Chakdara, Dir (Pakistan). Dept. of Chemistry; Bangash, Fazlullah Khan [Peshawar Univ. (Pakistan). Inst. of Chemical Sciences; Amin, Noor-ul [Abdul Wali Khan Univ., Mardan (Pakistan). Dept. of Chemistry

    2013-09-15

    Removal of heavy metals i.e. Zn{sup 2+} and Cd{sup 2+} from aqueous solution by adsorption onto biomass based adsorbent was investigated as a function of time and different concentrations. The sample was characterized by FTIR, EDS, BET surface area and Zeta potential technique, which was reported earlier. Adsorption kinetics of Zn{sup 2+} and Cd{sup 2+} was tested by first order kinetics, 'Elovich and parabolic diffusion kinetic equations which show that the process of adsorption is diffusion controlled process. The rate of adsorption was high at high adsorption temperature. Thermodynamic parameters like {Delta}H , {Delta}S and {Delta}G were calculated from the kinetic data. The negative value of Gibbs free energy ({Delta}G ) shows the spontaneous nature of the process. Freundlich, Langmuir, Temkin isotherms and distribution coefficient were found fit to the adsorption isotherm data. (orig.)

  1. Removing label ambiguity in learning-based visual saliency estimation.

    Science.gov (United States)

    Li, Jia; Xu, Dong; Gao, Wen

    2012-04-01

    Visual saliency is a useful clue to depict visually important image/video contents in many multimedia applications. In visual saliency estimation, a feasible solution is to learn a "feature-saliency" mapping model from the user data obtained by manually labeling activities or eye-tracking devices. However, label ambiguities may also arise due to the inaccurate and inadequate user data. To process the noisy training data, we propose a multi-instance learning to rank approach for visual saliency estimation. In our approach, the correlations between various image patches are incorporated into an ordinal regression framework. By iteratively refining a ranking model and relabeling the image patches with respect to their mutual correlations, the label ambiguities can be effectively removed from the training data. Consequently, visual saliency can be effectively estimated by the ranking model, which can pop out real targets and suppress real distractors. Extensive experiments on two public image data sets show that our approach outperforms 11 state-of-the-art methods remarkably in visual saliency estimation.

  2. Mathematical modeling based evaluation and simulation of boron removal in bioelectrochemical systems

    Energy Technology Data Exchange (ETDEWEB)

    Ping, Qingyun [Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Abu-Reesh, Ibrahim M. [Department of Chemical Engineering, College of Engineering, Qatar University, P.O. Box 2713, Doha (Qatar); He, Zhen, E-mail: zhenhe@vt.edu [Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States)

    2016-11-01

    Boron removal is an arising issue in desalination plants due to boron's toxicity. As an emerging treatment concept, bioelectrochemical systems (BES) can achieve potentially cost-effective boron removal by taking advantage of cathodic-produced alkali. Prior studies have demonstrated successful removal of boron in microbial desalination cells (MDCs) and microbial fuel cells (MFCs), both of which are representative BES. Herein, mathematical models were developed to further evaluate boron removal by different BES and understand the key operating factors. The models delivered very good prediction of the boron concentration in the MDC integrated with Donnan Dialysis (DD) system with the lowest relative root-mean-square error (RMSE) of 0.00%; the predication of the MFC performance generated the highest RMSE of 18.55%. The model results of salt concentration, solution pH, and current generation were well fitted with experimental data for RMSE values mostly below 10%. The long term simulation of the MDC-DD system suggests that the accumulation of salt in the catholyte/stripping solution could have a positive impact on the removal of boron due to osmosis-driven convection. The current generation in the MDC may have little influence on the boron removal, while in the MFC the current-driven electromigration can contribute up to 40% of boron removal. Osmosis-induced convection transport of boron could be the major driving force for boron removal to a low level < 2 mg L{sup −} {sup 1}. The ratio between the anolyte and the catholyte flow rates should be kept > 22.2 in order to avoid boron accumulation in the anolyte effluent. - Highlights: • Mathematical models are developed to understand boron removal in BES. • Boron removal can be driven by electromigration induced by current generation. • Diffusion induced by a salt concentration gradient also contributes to boron removal. • Osmosis and current driven convection transport play diverse roles in different BES.

  3. Enhanced Arsenate Removal Performance in Aqueous Solution by Yttrium-Based Adsorbents

    Directory of Open Access Journals (Sweden)

    Sang-Ho Lee

    2015-10-01

    Full Text Available Arsenic contamination in drinking water has become an increasingly important issue due to its high toxicity to humans. The present study focuses on the development of the yttrium-based adsorbents, with basic yttrium carbonate (BYC, Ti-loaded basic yttrium carbonate (Ti-loaded BYC and yttrium hydroxide prepared using a co-precipitation method. The Langmuir isotherm results confirmed the maximum adsorption capacity of Ti-loaded BYC (348.5 mg/g was 25% higher than either BYC (289.6 mg/g or yttrium hydroxide (206.5 mg/g due to its increased specific surface area (82 m2/g and surface charge (PZC: 8.4. Pseudo first- and second-order kinetic models further confirmed that the arsenate removal rate of Ti-loaded BYC was faster than for BYC and yttrium hydroxide. It was subsequently posited that the dominant removal mechanism of BYC and Ti-loaded BYC was the carbonate-arsenate ion exchange process, whereas yttrium hydroxide was regarded to be a co-precipitation process. The Ti-loaded BYC also displayed the highest adsorption affinity for a wide pH range (3–11 and in the presence of coexisting anionic species such as phosphate, silicate, and bicarbonate. Therefore, it is expected that Ti-loaded BYC can be used as an effective and practical adsorbent for arsenate remediation in drinking water.

  4. Efficient TEA CO 2 laser based coating removal system

    CSIR Research Space (South Africa)

    Prinsloo, FJ

    2007-04-01

    Full Text Available A high power 1kW pulsed transversely excited atmospheric CO 2 laser that has been developed for the paint stripping of missiles was used to test paint stripping on several metallic and composite aircraft panels to determine the rate at which...

  5. Utilization of Anabaena sp. in CO₂ removal processes: modelling of biomass, exopolysaccharides productivities and CO₂ fixation rate.

    Science.gov (United States)

    Sánchez Fernández, J F; González-López, C V; Acién Fernández, F G; Fernández Sevilla, J M; Molina Grima, E

    2012-05-01

    This paper focuses on modelling the growth rate and exopolysaccharides production of Anabaena sp. ATCC 33047, to be used in carbon dioxide removal and biofuels production. For this, the influence of dilution rate, irradiance and aeration rate on the biomass and exopolysaccharides productivity, as well as on the CO(2) fixation rate, have been studied. The productivity of the cultures was maximum at the highest irradiance and dilution rate assayed, resulting to 0.5 g(bio) l(-1) day(-1) and 0.2 g(eps) l(-1) day(-1), and the CO(2) fixation rate measured was 1.0 gCO(2) l(-1) day(-1). The results showed that although Anabaena sp. was partially photo-inhibited at irradiances higher than 1,300 μE m(-2) s(-1), its growth rate increases hyperbolically with the average irradiance inside the culture, and so does the specific exopolysaccharides production rate. The latter, on the other hand, decreases under high external irradiances, indicating that the exopolysaccharides metabolism hindered by photo-damage. Mathematical models that consider these phenomena have been proposed. Regarding aeration, the yield of the cultures decreased at rates over 0.5 v/v/min or when shear rates were higher than 60 s(-1), demonstrating the existence of thus existence of stress damage by aeration. The behaviour of the cultures has been verified outdoors in a pilot-scale airlift tubular photobioreactor. From this study it is concluded that Anabaena sp. is highly recommended to transform CO(2) into valuable products as has been proved capable of metabolizing carbon dioxide at rates of 1.2 gCO(2) l(-1) day(-1) outdoors. The adequacy of the proposed equations is demonstrated, resulting to a useful tool in the design and operation of photobioreactors using this strain.

  6. Chemomechanical caries removal method versus mechanical caries removal methods in clinical and community-based setting: A comparative in vivo study

    OpenAIRE

    Kumar, K.V.K Santosh; Prasad, M. Ghanashyam; Sandeep, R. Venkata; Reddy, S. Pavani; D. Divya; Pratyusha, K.

    2016-01-01

    Objective: To compare the effectiveness of various caries removal techniques in mandibular primary molars using Smart Burs, atraumatic restorative technique (ART) (mechanical caries removal) and Carie-care (chemomechanical caries removal [CMCR]) among primary school children in clinical and community-based settings. Materials and Methods: A total of 80 carious primary mandibular molars were selected for the study from the dental clinic and community. They were equally assigned to four groups ...

  7. The Impact on Women on the Removal of Gender as a Rating ...

    African Journals Online (AJOL)

    Should a South African court decide that the use of gender as a motor-vehicle insurance rating variable is unfair discrimination, this would benefit male drivers, as it would lower their premium. Women, on the other hand, would be disadvantaged as they would be required to pay higher premiums to subsidise men.

  8. 76 FR 44262 - Removing Any Reference to or Reliance on Credit Ratings in Commission Regulations; Proposing...

    Science.gov (United States)

    2011-07-25

    ...) Protection of market participants and the public; (2) efficiency, competitiveness and financial integrity of... market participants and the public, promote the financial integrity of futures markets, and enhance sound... that rely on credit ratings regarding financial instruments. \\2\\ Commission regulations that are...

  9. Optimization of parameters on material removal rate in micro-WEDG ...

    African Journals Online (AJOL)

    In this work, an orthogonal array, signal to noise (S/N) ratio and Pareto analysis of variance (ANOVA) are employed to analyze the effect of the micro-WEDG parameters such as feed rate, capacitance and voltage on MRR. This paper focuses on the Taguchi technique for the optimization in micro-WEDG process to achieve ...

  10. Impact of temperature on ammonium and nitrite removal rates in RAS moving bed biofilters

    DEFF Research Database (Denmark)

    Kinyage, John Peter Hewa; Pedersen, Lars-Flemming

    2016-01-01

    by using moving bed bio-elements from a freshwater RAS in steady state operated at 18 °C. The impact of temperature on ammonium and nitrite oxidation rates was evaluated by transferring the colonized bio elements to six liter batch reactors (triplicated setup). Each reactor was acclimatized for 24 h...

  11. Performance comparison of constructed wetlands with gravel- and rice husk-based media for phenol and nitrogen removal.

    Science.gov (United States)

    Tee, H C; Seng, C E; Noor, A Md; Lim, P E

    2009-05-15

    This study aims to compare the performance of planted and unplanted constructed wetlands with gravel- and raw rice husk-based media for phenol and nitrogen removal. Four laboratory-scale horizontal subsurface-flow constructed wetland units, two of which planted with cattail (Typha latifolia) were operated outdoors. The units were operated at a nominal hydraulic retention time of 7 days and fed with domestic wastewater spiked with phenol concentration at 300 mg/L for 74 days and then at 500 mg/L for 198 days. The results show that planted wetland units performed better than the unplanted ones in the removal and mineralization of phenol. This was explained by the creation of more micro-aerobic zones in the root zone of the wetland plants which allow a faster rate of phenol biodegradation, and the phenol uptake by plants. The better performance of the rice husk-based planted wetland compared to that of the gravel-based planted wetland in phenol removal could be explained by the observation that more rhizomes were established in the rice husk-based wetland unit thus creating more micro-aerobic zones for phenol degradation. The role of rice husk as an adsorbent in phenol removal was considered not of importance.

  12. High nutrient removal rate from swine wastes and protein biomass production by full-scale duckweed ponds.

    Science.gov (United States)

    Mohedano, Rodrigo A; Costa, Rejane H R; Tavares, Flávia A; Belli Filho, Paulo

    2012-05-01

    Duckweed ponds have been successfully used in swine waste polishing, generating a biomass with high protein content. Therefore, the present study evaluated the efficiency of two full-scale duckweed ponds considering nutrient recovery from a piggery farm effluent (produced by 300 animals), as well as the biomass yield and crude protein (CP) content. A significant improvement in the effluent quality was observed, with the removal of 98.0% of the TKN (Total Kjeldahl Nitrogen) and 98.8% of the TP (Total Phosphorous), on average. The observed nitrogen removal rate is one of the highest reported (4.4 g/m(2)day of TKN). Additionally, the dissolved oxygen level rose from 0.0 to 3.0mg/L, on average. The two ponds together produced over 13 tons of biomass (68 t/ha year of dry biomass), with 35% crude protein content. Because of the excellent nutrient removal and protein biomass production, the duckweed ponds revealed a great potential for the polishing and valorisation of swine waste, under the presented conditions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Removal of the veterinary antimicrobial sulfamethazine in a horizontal-flow anaerobic immobilized biomass (HAIB) reactor subjected to step changes in the applied organic loading rate.

    Science.gov (United States)

    Oliveira, G H D; Santos-Neto, A J; Zaiat, M

    2017-12-15

    A bench-scale horizontal-flow anaerobic immobilized biomass (HAIB) reactor treating synthetic swine wastewater was operated under different applied organic loading rates (OLR) through both variations in feed strength and in hydraulic retention time (HRT). The influence of step changes in OLR on the removal of the veterinary antimicrobial sulfamethazine (SMZ) was assessed. The highest observed SMZ removal efficiency, 75 ± 6%, was achieved with an OLR of 2.7 ± 0.4 kg O 2  m -3  d -1 when a significant increase in COD removal rate was observed. The SMZ removal rate was positively correlated (r = 0.899) to the COD removal rate in all of the experimental conditions in which the HRT was kept at 24 h, indicating a cometabolic transformation of the antimicrobial. Decreasing the HRT caused a significant decrease in SMZ removal efficiency without affecting the HAIB reactor performance in terms of stability, COD removal or metabolic intermediates production. Functionally equivalent steady states were observed in four different operational phases with similar operating conditions but with widely different behavior in relation to SMZ removal. The experimental results showed the potential of anaerobic technology in removing environmentally relevant concentrations of SMZ, and the possibility of enhancing reactor performance by controlling operating conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. The effects of automated artifact removal algorithms on electroencephalography-based Alzheimer's disease diagnosis

    Science.gov (United States)

    Cassani, Raymundo; Falk, Tiago H.; Fraga, Francisco J.; Kanda, Paulo A. M.; Anghinah, Renato

    2014-01-01

    Over the last decade, electroencephalography (EEG) has emerged as a reliable tool for the diagnosis of cortical disorders such as Alzheimer's disease (AD). EEG signals, however, are susceptible to several artifacts, such as ocular, muscular, movement, and environmental. To overcome this limitation, existing diagnostic systems commonly depend on experienced clinicians to manually select artifact-free epochs from the collected multi-channel EEG data. Manual selection, however, is a tedious and time-consuming process, rendering the diagnostic system “semi-automated.” Notwithstanding, a number of EEG artifact removal algorithms have been proposed in the literature. The (dis)advantages of using such algorithms in automated AD diagnostic systems, however, have not been documented; this paper aims to fill this gap. Here, we investigate the effects of three state-of-the-art automated artifact removal (AAR) algorithms (both alone and in combination with each other) on AD diagnostic systems based on four different classes of EEG features, namely, spectral, amplitude modulation rate of change, coherence, and phase. The three AAR algorithms tested are statistical artifact rejection (SAR), blind source separation based on second order blind identification and canonical correlation analysis (BSS-SOBI-CCA), and wavelet enhanced independent component analysis (wICA). Experimental results based on 20-channel resting-awake EEG data collected from 59 participants (20 patients with mild AD, 15 with moderate-to-severe AD, and 24 age-matched healthy controls) showed the wICA algorithm alone outperforming other enhancement algorithm combinations across three tasks: diagnosis (control vs. mild vs. moderate), early detection (control vs. mild), and disease progression (mild vs. moderate), thus opening the doors for fully-automated systems that can assist clinicians with early detection of AD, as well as disease severity progression assessment. PMID:24723886

  15. The effects of automated artifact removal algorithms on electroencephalography-based Alzheimer’s disease diagnosis

    Directory of Open Access Journals (Sweden)

    Raymundo eCassani

    2014-03-01

    Full Text Available Over the last decade, electroencephalography (EEG has emerged as a reliable tool for the diagnosis of cortical disorders such as Alzheimer's disease (AD. EEG signals, however, are susceptible to several artifacts, such as ocular, muscular, movement, and environmental. To overcome this limitation, existing diagnostic systems commonly depend on experienced clinicians to manually select artifact-free epochs from the collected multi-channel EEG data. Manual selection, however, is a tedious and time-consuming process, rendering the diagnostic system ``semi-automated. Notwithstanding, a number of EEG artifact removal algorithms have been proposed in the literature. The (disadvantages of using such algorithms in automated AD diagnostic systems, however, have not been documented; this paper aims to fill this gap. Here, we investigate the effects of three state-of-the-art automated artifact removal (AAR algorithms (both alone and in combination with each other on AD diagnostic systems based on four different classes of EEG features, namely, spectral, amplitude modulation rate of change, coherence, and phase. The three AAR algorithms tested are statistical artifact rejection (SAR, blind source separation based on second order blind identification and canonical correlation analysis (BSS-SOBI-CCA, and wavelet enhanced independent component analysis (wICA. Experimental results based on 20-channel resting-awake EEG data collected from 59 participants (20 patients with mild AD, 15 with moderate-to-severe AD, and 24 age-matched healthy controls showed the wICA algorithm alone outperforming other enhancement algorithm combinations across three tasks: diagnosis (control vs. mild vs. moderate, early detection (control vs. mild, and disease progression (mild vs. moderate, thus opening the doors for fully-automated systems that can assist clinicians with early detection of AD, as well as disease severity progression assessment.

  16. A rate-based approach to cleaning-in-place

    OpenAIRE

    Trinh, Linda; Willey, A. Roy; Martin, Peter J.; Ashley, Jon; Tothill, Ibtisam E.; Rodgers, Thomas Lawrence

    2017-01-01

    Fouling is a major problem in the food industry. In cases where allergens are involved, excessive cleaning of food processing equipment often takes place to ensure allergen levels are reduced to acceptable levels. Experimental trials were conducted in a pilot scale cleaning rig to assess the effect of fluid flow rate and temperature on the removal rate of milk paste during cleaning-in-place. Conductivity measurements taken during trials were analysed to produce an equation enabling calculatio...

  17. [Study on the calcium-based sorbent for removal fluorine during coal combustion].

    Science.gov (United States)

    Li, Shu-ling; Qi, Qing-jie; Liu, Jian-zhong; Cao, Xin-yu; Zhou, Jun-hu; Cen, Ke-fa

    2004-03-01

    In the paper, the reaction of CaO-HF and fluorine removal mechanics at high temperature by blending calcium-based sorbents with coal during coal combustion were discussed, and test results about fluorine retention during coal combustion in fluidized bed and chain-grate furnace were reported. The results identified that lime and calcium-based sorbets developed can restratin the emission of fluorine during coal combustion. The efficiency of fluorine removal can reach 66.7%-70.0% at Ca/F 60-70 by blending lime with coal in fluidized bed combustion, and the efficiency of fluorine removal are between 57.32% and 75.19% by blending calcium-based sorbets with coal in chain-grate furnace combustion. Blending CaO or lime with coal during coal combustion can remove SO2 and HF simultaneously.

  18. Effect of inspiratory flow rate on the efficiency of carbon dioxide removal at tidal volumes below instrumental dead space.

    Science.gov (United States)

    Hurley, Edward H; Keszler, Martin

    2017-03-01

    The ability to ventilate babies with tidal volumes (VTs) below dead space has been demonstrated both in vivo and in vitro, though it appears to violate classical respiratory physiology. We hypothesised that this phenomenon is made possible by rapid flow of gas that penetrates the dead space allowing fresh gas to reach the lungs and that the magnitude of this phenomenon is affected by flow rate or how rapidly air flows through the endotracheal tube. We conducted two bench experiments. First, we measured the time needed for complete CO2 washout from a test lung to assess how fixed VT but different inflation flow rates affect ventilation. For the second experiment, we infused carbon dioxide at a low rate into the test lung, varied the inflation flow rate and adjusted the VT to maintain stable end tidal carbon dioxide (ETCO2). At all tested VTs, lower flow rate increased the time it took for CO2 to washout from the test lung. The effect was most pronounced for VTs below dead space. The CO2 steady-state experiment showed that ETCO2 increased when the flow rate decreased. Ventilating with a slower flow rate required a nearly 20% increase in VT for the same effective alveolar ventilation. Inflation flow rate affects the efficiency of CO2 removal with low VT. Our results are relevant for providers using volume-controlled ventilation or other modes that use low inflation flow rates because the VT required for normocapnia will be higher than published values that were generated using pressure-limited ventilation modes with high inflation flows. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  19. A passive decay-heat removal system for an ABWR based on air cooling

    Energy Technology Data Exchange (ETDEWEB)

    Mochizuki, Hiroyasu, E-mail: mochizki@u-fukui.ac.jp [Research Institute of Nuclear Engineering, University of Fukui, 1-2-4 Kanawa-cho, Tsuruga, Fukui 914-0055 (Japan); Yano, Takahiro [School of Engineering, University of Fukui, 1-2-4 Kanawa-cho, Tsuruga, Fukui 914-0055 (Japan)

    2017-01-15

    Highlights: • A passive decay heat removal system for an ABWR is discussed using combined system of the reactor and an air cooler. • Effect of number of pass of the finned heat transfer tubes on heat removal is investigated. • The decay heat can be removed by air coolers with natural convection. • Two types of air cooler are evaluated, i.e., steam condensing and water cooling types. • Measures how to improve the heat removal rate and to make compact air cooler are discussed. - Abstract: This paper describes the capability of an air cooling system (ACS) operated under natural convection conditions to remove decay heat from the core of an Advanced Boiling Water Reactor (ABWR). The motivation of the present research is the Fukushima Severe Accident (SA). The plant suffered damages due to the tsunami and entered a state of Station Blackout (SBO) during which seawater cooling was not available. To prevent this kind of situation, we proposed a passive decay heat removal system (DHRS) in the previous study. The plant behavior during the SBO was calculated using the system code NETFLOW++ assuming an ABWR with the ACS. However, decay heat removal under an air natural convection was difficult. In the present study, a countermeasure to increase heat removal rate is proposed and plant transients with the ACS are calculated under natural convection conditions. The key issue is decreasing pressure drop over the tube banks in order to increase air flow rate. The results of the calculations indicate that the decay heat can be removed by the air natural convection after safety relief valves are actuated many times during a day. Duct height and heat transfer tube arrangement of the AC are discussed in order to design a compact and efficient AC for the natural convection mode. As a result, a 4-pass heat transfer tubes with 2-row staggered arrangement is the candidate of the AC for the DHRS under the air natural convection conditions. The heat removal rate is re-evaluated as

  20. Nitrogen removal in permeable woodchips filters affected by hydraulic loading rate and woodchips ratio

    DEFF Research Database (Denmark)

    Bruun, Jacob Druedahl; Kjærgaard, Charlotte; Hoffmann, Carl Christian

    2016-01-01

    Unregulated and event-driven agricultural tile drainage discharge poses several challenges that potentially limit the nitrate (NO3) reduction in woodchip-based constructed wetland systems intercepting subsurface tile drains. Laboratory column tests were conducted to evaluate the biogeochemical re...

  1. Chitosan-based biocatalytic nanoparticles for pollutant removal from wastewater.

    Science.gov (United States)

    Alarcón-Payán, Dulce A; Koyani, Rina D; Vazquez-Duhalt, Rafael

    2017-05-01

    Chitosan, a renewable biopolymer has the prospective applications in different fields due to its gelation capacity. Nanoconfiguration of chitosan through ionotropic gelation to encapsulate enzymatic activity offers numerous potential applications. In the present study, the preparation and characterization of chitosan nanoparticles loaded with versatile peroxidase are reported. Their performance in bioremediation process and the resistance enhancement against natural microbial biodegradation were studied. The average diameter of enzymatic nanoparticles was 120nm and showed a high enzyme loading capacity. The kinetic parameters of nanoparticles exhibited a slightly lower catalytic activity (k cat ), similar affinity constant (Km) for hydrogen peroxide and higher Km value for the phenolic compound when compared with the free enzyme. The enzymatic nanoparticles showed higher thermostability and the same pH activity profile than those from free enzyme. Ten phenolic compounds, including pesticides, halogenated compounds, endocrine disruptors and antibacterials were transformed by the enzymatic nanoparticles. The transformation rate was lower than those obtained with free enzyme suggesting mass transfer limitations. But very importantly, the enzymatic nanoparticles showed a significant increase of the operational stability in real conditions of wastewater treatment process. Moreover, chemical modification of nanoparticles with different aldehydes still enhanced the operational stability of nanoparticulated enzymes. This enhancement of stability in real conditions and the potential use of biocatalytic nanoparticles in bioremediation processes are discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Postoperative Infection Rates in Patients with a Negative Baseline Urine Culture Undergoing Ureteroscopic Stone Removal

    DEFF Research Database (Denmark)

    Martov, Alexey; Gravas, Stavros; Etemadian, Masoud

    2015-01-01

    placement. Patient characteristics, operative data, and postoperative outcomes, including the development of urinary tract infection (UTI) and fever, in the two groups were compared. Results: Antibiotic prophylaxis use differed widely across participating countries (13%-100%). Differences were found between......Abstract Purpose: To examine the effects of antibiotic prophylaxis on postoperative infection rate in patients with negative urine cultures undergoing ureteroscopy (URS). Patients and Methods: Using the Clinical Research Office of the Endourological Society (CROES) URS Global Study database...... patients who did or did not receive antibiotic prophylaxis regarding the frequency of anticoagulation medication, previous treatment with URS, stone burden, previous presence of kidney stones, duration of current URS, and complications post-URS. The prevalence of fever and UTI was low (≤2.2%) and similar...

  3. Rolling-Bearing Service Life Based on Probable Cause for Removal: A Tutorial

    Science.gov (United States)

    Zaretsky, Erwin V.; Branzai, Emanuel V.

    2017-01-01

    In 1947 and 1952, Gustaf Lundberg and Arvid Palmgren developed what is now referred to as the Lundberg-Palmgren Model for Rolling Bearing Life Prediction based on classical rolling-element fatigue. Today, bearing fatigue probably accounts for less than 5 percent of bearings removed from service for cause. A bearing service life prediction methodology and tutorial indexed to eight probable causes for bearing removal, including fatigue, are presented, which incorporate strict series reliability; Weibull statistical analysis; available published field data from the Naval Air Rework Facility; and 224,000 rolling-element bearings removed for rework from commercial aircraft engines.

  4. Influence of the Chemical Interactions on the Removal Rate of Different Salts in Electrokinetic Desalination Processes

    DEFF Research Database (Denmark)

    Paz-Garcia, Juan Manuel; Johannesson, Björn; Ottosen, Lisbeth M.

    2011-01-01

    Electrokinetic desalination techniques have been successfully applied for the prevention of salt-induced deterioration problems of masonry and other construction materials. A mathematical model for electrochemical desalination treatments is described, based on the Poisson-Nernst-Planck system...... and sculptures. Simulations of the desalination treatment of brick samples contaminated with these target contaminants are shown. The influence of the chemical interactions on the efficiency is highlighted in the results....

  5. Chemical Burn from Vinegar Following an Internet-based Protocol for Self-removal of Nevi.

    Science.gov (United States)

    Feldstein, Stephanie; Afshar, Maryam; Krakowski, Andrew C

    2015-06-01

    "Natural home remedies" for nevi removal found on the Internet can be ineffective, or worse, dangerous. Children and teens, in particular, may be more likely to attempt self-treatment in order to avoid discussing their concerns with their parents. Here, the authors report a case of an adolescent who presented with a chemical burn after following an Internet-based protocol for nevi removal using apple cider vinegar.

  6. Chemical Bum from Vinegar Following an Internet-based Protocol for Self-removal of Nevi

    Science.gov (United States)

    Feldstein, Stephanie; Afshar, Maryam

    2015-01-01

    “Natural home remedies” for nevi removal found on the Internet can be ineffective, or worse, dangerous. Children and teens, in particular, may be more likely to attempt self-treatment in order to avoid discussing their concerns with their parents. Here, the authors report a case of an adolescent who presented with a chemical burn after following an Internet-based protocol for nevi removal using apple cider vinegar. PMID:26155328

  7. A field survey of the partially edentate elderly: Investigation of factors related to the usage rate of removable partial dentures.

    Science.gov (United States)

    Murai, S; Matsuda, K; Ikebe, K; Enoki, K; Hatta, K; Fujiwara, K; Maeda, Y

    2015-11-01

    Although the shortened dental arch (SDA) concept has been known to all over the world, acceptance of the SDA concept as an oral health standard can be questionable from the patients' point of view, even if it is biologically reasonable. Furthermore, because the health insurance system covers removable partial dentures (RPDs) for all citizens in Japan, SDA patients seem to prefer to receive prosthetic treatment to replace the missing teeth. However, there were few field surveys to investigate the usage rate of RPDs in Japan. The purpose of this study was to determine the usage rate of RPDs in older Japanese subjects and to investigate the factors related to the usage of RPDs. Partially edentate participants (n = 390) were included in this study. Oral examinations were conducted to record several indices. The Cochran-Armitage trend test was used to evaluate the relationship between the number of missing teeth and the usage rate of RPDs. Chi-squared tests and logistic regression analysis were conducted to evaluate the factors related to the usage rate of RPDs. Usage of RPDs had a significantly positive association with the number of missing distal extension teeth and bilaterally missing teeth. The usage rate of RPDs increased as the number of missing distal extension teeth increased (P for trend < 0·001). The conclusion of this study was that participants with missing distal extension teeth had higher usage rates of RPDs than other participants, and the usage rate increased as the number of missing distal extension teeth increased. © 2015 John Wiley & Sons Ltd.

  8. Dam Removal Information Portal (DRIP)—A map-based resource linking scientific studies and associated geospatial information about dam removals

    Science.gov (United States)

    Duda, Jeffrey J.; Wieferich, Daniel J.; Bristol, R. Sky; Bellmore, J. Ryan; Hutchison, Vivian B.; Vittum, Katherine M.; Craig, Laura; Warrick, Jonathan A.

    2016-08-18

    The removal of dams has recently increased over historical levels due to aging infrastructure, changing societal needs, and modern safety standards rendering some dams obsolete. Where possibilities for river restoration, or improved safety, exceed the benefits of retaining a dam, removal is more often being considered as a viable option. Yet, as this is a relatively new development in the history of river management, science is just beginning to guide our understanding of the physical and ecological implications of dam removal. Ultimately, the “lessons learned” from previous scientific studies on the outcomes dam removal could inform future scientific understanding of ecosystem outcomes, as well as aid in decision-making by stakeholders. We created a database visualization tool, the Dam Removal Information Portal (DRIP), to display map-based, interactive information about the scientific studies associated with dam removals. Serving both as a bibliographic source as well as a link to other existing databases like the National Hydrography Dataset, the derived National Dam Removal Science Database serves as the foundation for a Web-based application that synthesizes the existing scientific studies associated with dam removals. Thus, using the DRIP application, users can explore information about completed dam removal projects (for example, their location, height, and date removed), as well as discover sources and details of associated of scientific studies. As such, DRIP is intended to be a dynamic collection of scientific information related to dams that have been removed in the United States and elsewhere. This report describes the architecture and concepts of this “metaknowledge” database and the DRIP visualization tool.

  9. An Internet-based survey on characteristics of laser tattoo removal and associated side effects.

    Science.gov (United States)

    Klein, Annette; Rittmann, Ines; Hiller, Karl-Anton; Landthaler, Michael; Bäumler, Wolfgang

    2014-03-01

    Tattoo removal by laser therapy is a frequently performed procedure in dermatological practices. Quality-switched ruby, alexandrite, or Nd:YAG lasers are the most suitable treatment devices. Although these techniques are regarded as safe, both temporary and permanent side effects might occur. Little has been published on the frequency of complications associated with laser tattoo removal. We performed an Internet survey in German-speaking countries on characteristics of laser tattoo removal and associated side effects. A total number of 157 questionnaires entered the final analysis. Motivations for laser tattoo removal were mainly considering the tattoo as youthful folly (29%), esthetic reasons (28%), and 6% indicated medical problems. One third of participants were unsatisfied with the result of laser tattoo removal, and a complete removal of the tattoo pigment was obtained in 38% only. Local transient side effects occurred in nearly all participants, but an important rate of slightly visible scars (24%) or even important scarring (8%) was reported. Every fourth participant described mild or intense tan when the laser treatment was performed, and the same number of people indicated UV exposure following laser therapy, which should normally be avoided in these circumstances. As reported in the literature, nearly half of the participants experienced hypopigmentation in the treated area. Our results show that from the patients' point of view there is an important rate of side effects occurring after laser tattoo removal. Appropriate pretreatment counseling with regard to realistic expectations, possible side effects, and the application of test spots is mandatory to ensure patient satisfaction. Laser treatment should be performed by appropriately trained personnel only.

  10. Removal of a self-knotted feeding jejunostomy tube in a patient with tongue base cancer.

    Science.gov (United States)

    Jwo, S-C

    2010-09-01

    The knotting of an intragastric tube is a rare complication, and knotting of a feeding jejunostomy tube is rarer, and the removal or replacement of the tube is difficult. There are many reports on the removal of intragastric knotted tubes, but these methods cannot be applied for the removal of knotted feeding jejunostomy tubes, which do not have a natural orifice as large as the mouth to facilitate the introduction of instruments to correct the complication or remove the knotted tube. This is a stressful situation and doctors have to adopt strategies to resolve this problem safely and effectively in the absence of strong evidence-based knowledge. The author presents the case of a patient with tongue base cancer with a nasogastric feeding jejunostomy tube that knotted during the therapeutic course and describes a simple method to remove the knotted tube using Kelly clamps without additional invasive surgery. A literature review to elucidate methods for the removal of a self-knotted nasogastric tube, especially that occurring in feeding jejunostomy, is also reported. Copyright © 2010 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  11. Efficiency of recycled wool-based nonwoven material for the removal of oils from water

    NARCIS (Netherlands)

    Radetic, M.; Ilic, V.; Radojevic, D.; Miladinovic, R.; Jocic, D.; Javancic, P.

    2007-01-01

    The aim of this study was to highlight the potential use of recycled wool-based nonwoven material for the removal of diesel fuel, crude, base, vegetable and motor oil from water. Sorption capacity of the material in water and in oil without water, oil retention, sorbent reusability and buoyancy in

  12. Assessment of different pre-treatment methods for the removal of limonene in citrus waste and their effect on methane potential and methane production rate.

    Science.gov (United States)

    Ruiz, Begoña; de Benito, Amparo; Rivera, José Daniel; Flotats, Xavier

    2016-12-01

    The objective of this study was to assess the limonene removal efficiency of three pre-treatment methods when applied to citrus waste and to evaluate their effects on the biochemical methane potential and the methane production rate using batch anaerobic tests. The methods tested were based on removal (biological pretreatment by fungi) or recovery (steam distillation and ethanol extraction) of limonene. All the treatments decreased the concentration of limonene in orange peel, with average efficiencies of 22%, 44% and 100% for the biological treatment, steam distillation and ethanol extraction, respectively. By-products from limonene biodegradation by fungi exhibited an inhibitory effect also, not making interesting the biological pretreatment. The methane potential and production rate of the treated orange peel increased significantly after applying the recovery strategies, which separated and recovered simultaneously other inhibitory components of the citrus essential oil. Apart from the high recovery efficiency of the ethanol extraction process, it presented a favourable energy balance. © The Author(s) 2016.

  13. Implementation of ferric hydroxide-based media for removal of toxic metalloids

    Directory of Open Access Journals (Sweden)

    Szlachta Małgorzata

    2017-01-01

    Full Text Available Effective removal of inorganic arsenic species is possible by application of the sorption technique with the use of iron-based sorbents. This study investigates the removal of arsenic(III and arsenic(V from an aqueous solution by application of a granular ferric hydroxide-based sorbent. The performance of tested media was evaluated based on the batch and fixed-bed adsorption studies. The efficiency of the process was determined with various treatment times, adsorbent doses, initial concentrations of arsenic and various solution temperatures. The obtained adsorption data were fitted with pseudo-first and second-order kinetic models and Langmuir and Freundlich isotherm equations. It was observed that the overall arsenite removal was lower when compared to the arsenate, and all tested operating parameters influenced the process efficiency. The experiments under dynamic conditions showed high treatment capacity and stability of tested adsorbent over a long period of time.

  14. The high cost of improper removal of lead-based paint from housing: a case report.

    OpenAIRE

    Jacobs, David E; Mielke, Howard; Pavur, Nancy

    2003-01-01

    The costs of lead-based paint hazard control in housing are well documented, but the costs of cleanup after improper, inherently dangerous, methods of removing lead-based paint are not. In this article we report a case of childhood lead poisoning and document the costs of decontamination after uncontained power sanding was used to remove paint down to bare wood from approximately 3,000 ft(2) of exterior siding on a large, well-maintained 75-year-old house in a middle-income neighborhood. Afte...

  15. Catalytic decomposition of H2O2 over Fe-based catalysts for simultaneous removal of NOX and SO2

    Science.gov (United States)

    Huang, Xianming; Ding, Jie; Zhong, Qin

    2015-01-01

    Simultaneous flue gas desulfurization and denitrification were achieved with rad OH radicals from the decomposition of H2O2 over hematite (Fe) as well as hematite supported on alumina (Fe-Al) and anatase (Fe-Ti). Under all conditions, SO2 achieved 100% removal, whereas NOX removal varies with the catalysts. The supporting of Fe over aluminum enhances the catalytic removal of NOX, whereas that of anatase presents negative effect. The NOX removal is determined by the decomposition rate of H2O2 into rad OH radicals over sbnd OH bonded with Fe (Fe-OH). The supporting of Fe over alumina enhances the content of Fe-OH and the points of zero charge (PZC) values, which are beneficial for the production of rad OH radicals. The supporting of Fe over anatase results in the formation of FeOTi, which cannot decompose H2O2 into rad OH radicals. Furthermore, H2O2 tends more to be reacted with TiOH to produce O2 over Fe-Ti. Finally, the enhancement mechanism of H2O2 decomposition over Fe-based catalysts is speculated. It has a contribution to the correct choice for supports and active ingredients of the catalyst in the future industrial applications.

  16. REMOVING SHADOWS FROM HIGH-RESOLUTION URBAN AERIAL IMAGES BASED ON COLOR CONSTANCY

    Directory of Open Access Journals (Sweden)

    Q. Ye

    2012-08-01

    Full Text Available A method is explored to remove tall building shadows in true color and color infrared urban aerial images based on the theory of color constancy. This paper first uses the specthem ratio and Otsu threshold segmentation methods to detect building shadows on urban aerial true color and color infrared aerial images. Then, based on the shadow detection result, one of the color constancy algorithms SoG (Shades of Gray is used to remove the shadows in aerial images with different p values of the Minkowski norm. Finally, the shadow removal results with different p values have been compared by brightness, contrast and average gradients. The experiments show that the result of this method based on color constancy has a good visual effect, and different from general scene image shadow removal, the aerial images get the best shadow removal result when p is 2. It means the two types of aerial images should not be simply regarded as gray world images.

  17. A study on discrete wavelet-based noise removal from EEG signals.

    Science.gov (United States)

    Asaduzzaman, K; Reaz, M B I; Mohd-Yasin, F; Sim, K S; Hussain, M S

    2010-01-01

    Electroencephalogram (EEG) serves as an extremely valuable tool for clinicians and researchers to study the activity of the brain in a non-invasive manner. It has long been used for the diagnosis of various central nervous system disorders like seizures, epilepsy, and brain damage and for categorizing sleep stages in patients. The artifacts caused by various factors such as Electrooculogram (EOG), eye blink, and Electromyogram (EMG) in EEG signal increases the difficulty in analyzing them. Discrete wavelet transform has been applied in this research for removing noise from the EEG signal. The effectiveness of the noise removal is quantitatively measured using Root Mean Square (RMS) Difference. This paper reports on the effectiveness of wavelet transform applied to the EEG signal as a means of removing noise to retrieve important information related to both healthy and epileptic patients. Wavelet-based noise removal on the EEG signal of both healthy and epileptic subjects was performed using four discrete wavelet functions. With the appropriate choice of the wavelet function (WF), it is possible to remove noise effectively to analyze EEG significantly. Result of this study shows that WF Daubechies 8 (db8) provides the best noise removal from the raw EEG signal of healthy patients, while WF orthogonal Meyer does the same for epileptic patients. This algorithm is intended for FPGA implementation of portable biomedical equipments to detect different brain state in different circumstances.

  18. Enhanced adsorption and regeneration with lignocellulose-based phosphorus removal media using molecular coating nanotechnology.

    Science.gov (United States)

    Kim, Juyoung; Mann, Justin D; Kwon, Soonjo

    2006-01-01

    The removal of phosphorus in point and non-point-source pollution has become one of the leading problems in water quality since the beginning of the 21st century. Several natural, domestic, and industrial treatment systems already exist, but with very limited efficiencies and serious procedural defects. Lignocellulose-based Anion Removal Media (LAM) was developed in association with iron nanocoating technology as means of phosphorus adsorption from various concentrations of contaminated water. Results revealed that trivalent iron coated lignocellulose pellets can be used to effectively remove phosphorus contaminants from point and non-point-source polluted water. Removal capacities of pelletized cotton media surpass existing materials for phosphorus removal by at least 22 times, while remaining both efficient and cost effective. The materials were also investigated for regeneration, yielding high removal capacities even after the fifth regeneration. Treatment methodology and outlines are proposed, and procedural mechanisms are explored in this study. An economic evaluation of this technology is also assessed for a practical application of LAM to point/non-point-source polluted water.

  19. Removal of Cu 2+ Ions from Aqueous Medium Using Clinoptilolite/Emeraldine Base Composite

    Directory of Open Access Journals (Sweden)

    Silviya I. Lavrova

    2016-12-01

    Full Text Available The aim of this study was to investigate the removal efficiency of in situ synthesized composites consisted of emeraldine base and clinoptilolite on copper ions removal from aqueous medium. Two composite materials (Composite I and Composite II with different quantity of clinoptilolite were synthesised. The influence of the composite dosage, the contact time and the initial copper ions concentration has been studied. The results show that the significant removal of the copper ions becomes at the first minute of the contact between the composite material and the aqueous medium and the longer contact time leads to increasing of the copper ions removal. The removal efficiency at the 1st minute was 57.5% and 77.3% using Composite Iand Composite II, respectively. Maximum removal efficiency of 87.3% and 96.8% was achieved at the same dosage of Composite I and Composite II, respectively, at contact time of 360 minutes and temperature of 24 °C.

  20. Application of cellulose nanofibers to remove water-based flexographic inks from wastewaters.

    Science.gov (United States)

    Balea, Ana; Monte, M Concepción; de la Fuente, Elena; Negro, Carlos; Blanco, Ángeles

    2017-02-01

    Water-based or flexographic inks in paper and plastic industries are more environmentally favourable than organic solvent-based inks. However, their use also creates new challenges because they remain dissolved in water and alter the recycling process. Conventional deinking technologies such as flotation processes do not effectively remove them. Adsorption, coagulation/flocculation, biological and membrane processes are either expensive or have negative health impacts, making the development of alternative methods necessary. Cellulose nanofibers (CNF) are biodegradable, and their structural and mechanical properties are useful for wastewater treatment. TEMPO-oxidised CNF have been evaluated for the decolourisation of wastewaters that contained copper phthalocyanine blue, carbon black and diarlyide yellow pigments. CNF in combination with a cationic polyacrylamide (cPAM) has also been tested. Jar-test methodology was used to evaluate the efficiency of the different treatments and cationic/anionic demand, turbidity and ink concentration in waters were measured. Results show that dual-component system for ink removal has a high potential as an alternative bio-based adsorbent for the removal of water-based inks. In addition, experiments varying CNF and cPAM concentrations were performed to optimise the ink-removal process. Ink concentration reductions of 100%, 87.5% and 83.3% were achieved for copper phthalocyanine blue, carbon black and diarlyide yellow pigments, respectively. Flocculation studies carried out show the decolourisation mechanism during the dual-component treatment of wastewaters containing water-based inks.

  1. A technique of anterior screw removal through a posterior costotransversectomy approach for posterior-based osteotomies.

    Science.gov (United States)

    Lewis, Stephen J; David, Kenny; Singer, Syndie; Bacon, Sarah A; Kopka, Michaela; Gray, Randolph; Magana, Sofia

    2010-05-15

    Case report. To describe a novel technique to remove anterior instrumentation from a posterior approach while performing posterior-based osteotomies for spinal deformities. Posterior-based osteotomies such as pedicle subtraction osteotomies (PSOs) and vertebral column resections are performed to restore sagittal alignment. The removal of previously placed anterior implants at the desired osteotomy level can often be challenging. We propose a technique for the removal of anterior instrumentation through a posterior approach to facilitate osteotomy closure and deformity correction, while avoiding the need for an anterior incision. A 34-year-old woman presented with a residual deformity after several anterior and posterior procedures. The residual coronal Cobb angle measured 60 degrees between T7 and L2, with a 46 degrees thoracolumbar kyphosis between T10 and L2. The screw head at the desired osteotomy level was in close proximity to the liver after the previous right-sided thoracoabdominal approach. Therefore, the T11 anterior screw was accessed through a posterior costotransversectomy approach and disconnected from the rod proximally and distally with a high-speed side-cutting burr. A portion of the right lateral vertebral body of T11 was removed to expose the neck of the screw, which was separated from the shaft with the same burr. A PSO was performed at T11 and the remaining screw shank was removed with the posterior-based osteotomy. No major complications were encountered during the procedure. The anterior screw at T11 was removed from posteriorly, and the PSO was completed successfully. Postoperative recovery was without incident, and the patient was very satisfied with her results. This technique describes a novel, safe, and effective method to deal with anterior instrumentation from the posterior approach while performing posterior-based osteotomies for rigid spinal deformities.

  2. Prediction of material removal rate and surface roughness for wire electrical discharge machining of nickel using response surface methodology

    Directory of Open Access Journals (Sweden)

    Thangam Chinnadurai

    2016-12-01

    Full Text Available This study focuses on investigating the effects of process parameters, namely, Peak current (Ip, Pulse on time (Ton, Pulse off time (Toff, Water pressure (Wp, Wire feed rate (Wf, Wire tension (Wt, Servo voltage (Sv and Servo feed setting (Sfs, on the Material Removal Rate (MRR and Surface Roughness (SR for Wire electrical discharge machining (Wire-EDM of nickel using Taguchi method. Response Surface Methodology (RSM is adopted to evolve mathematical relationships between the wire cutting process parameters and the output variables of the weld joint to determine the welding input parameters that lead to the desired optimal wire cutting quality. Besides, using response surface plots, the interaction effects of process parameters on the responses are analyzed and discussed. The statistical software Mini-tab is used to establish the design and to obtain the regression equations. The developed mathematical models are tested by analysis-of-variance (ANOVA method to check their appropriateness and suitability. Finally, a comparison is made between measured and calculated results, which are in good agreement. This indicates that the developed models can predict the responses accurately and precisely within the limits of cutting parameter being used.

  3. Recent measurements of the rates of ozone removal from the atmosphere by land surfaces. Paper 78-30. 5

    Energy Technology Data Exchange (ETDEWEB)

    Wesely, M.L.; Eastman, J.A.; Cook, D.R.; Hicks, B.B.

    1978-01-01

    The factors that control the uptake of airborne pollutants at land surfaces are highly varied and depend to a large extent on the chemical properties of the pollutant considered. Since ozone is not very soluble in pure water and is highly reactive with many substances, its uptake or destruction should be retarded by liquid water but enhanced by biological activity that produces substances susceptible to attack by ozone. It would appear that the variability in surface resistance to uptake of ozone is quite large due to the great natural variations in chemical composition, temperature, and water content of outdoor surfaces. Thus, the rates of removal of ozone from the atmosphere can be difficult to predict when flow over numerous kinds of surfaces is involved, such as in episodes of rather high ozone concentrations that occur over regional-scale distances (about 1000 km). The purpose of the present study is to examine measurements of ozone flux obtained directly by eddy-correlation techniques above certain agricultural surfaces, and to determine the surface properties, including estimated stomatal resistance, that are important in regulating the rate of ozone destruction at the surface. The two experimental sites were a large field of full-grown, healthy maize in Sangamon County near Springfield, Illinois, and the second site was a field of senescent maize in Rush County near Indianapolis, Indiana.

  4. Dam removal: Listening in

    Science.gov (United States)

    Foley, Melissa M.; Bellmore, James; O'Connor, James E.; Duda, Jeff; East, Amy E.; Grant, Gordon G.; Anderson, Chauncey; Bountry, Jennifer A.; Collins, Mathias J.; Connolly, Patrick J.; Craig, Laura S.; Evans, James E.; Greene, Samantha; Magilligan, Francis J.; Magirl, Christopher S.; Major, Jon J.; Pess, George R.; Randle, Timothy J.; Shafroth, Patrick B.; Torgersen, Christian; Tullos, Desiree D.; Wilcox, Andrew C.

    2017-01-01

    Dam removal is widely used as an approach for river restoration in the United States. The increase in dam removals—particularly large dams—and associated dam-removal studies over the last few decades motivated a working group at the USGS John Wesley Powell Center for Analysis and Synthesis to review and synthesize available studies of dam removals and their findings. Based on dam removals thus far, some general conclusions have emerged: (1) physical responses are typically fast, with the rate of sediment erosion largely dependent on sediment characteristics and dam-removal strategy; (2) ecological responses to dam removal differ among the affected upstream, downstream, and reservoir reaches; (3) dam removal tends to quickly reestablish connectivity, restoring the movement of material and organisms between upstream and downstream river reaches; (4) geographic context, river history, and land use significantly influence river restoration trajectories and recovery potential because they control broader physical and ecological processes and conditions; and (5) quantitative modeling capability is improving, particularly for physical and broad-scale ecological effects, and gives managers information needed to understand and predict long-term effects of dam removal on riverine ecosystems. Although these studies collectively enhance our understanding of how riverine ecosystems respond to dam removal, knowledge gaps remain because most studies have been short (< 5 years) and do not adequately represent the diversity of dam types, watershed conditions, and dam-removal methods in the U.S.

  5. Efficacy of reactive mineral-based sorbents for phosphate, bacteria, nitrogen and TOC removal--column experiment in recirculation batch mode.

    Science.gov (United States)

    Nilsson, Charlotte; Lakshmanan, Ramnath; Renman, Gunno; Rajarao, Gunaratna Kuttuva

    2013-09-15

    Two mineral-based materials (Polonite and Sorbulite) intended for filter wells in on-site wastewater treatment were compared in terms of removal of phosphate (PO4-P), total inorganic nitrogen (TIN), total organic carbon (TOC) and faecal indicator bacteria (Escherichia coli and Enterococci). Using an innovative, recirculating system, septic tank effluent was pumped at a hydraulic loading rate of 3000 L m(2) d(-1) into triplicate bench-scale columns of each material over a 90-day period. The results showed that Polonite performed better with respect to removal of PO4-P, retaining on average 80% compared with 75% in Sorbulite. This difference was attributed to higher CaO content in Polonite and its faster dissolution. Polonite also performed better in terms of removal of bacteria because of its higher pH value. The total average reduction in E. coli was 60% in Polonite and 45% in Sorbulite, while for Enterococci the corresponding value was 56% in Polonite and 34% in Sorbulite. Sorbulite removed TIN more effectively, with a removal rate of 23%, while Polonite removed 11% of TIN, as well as TOC. Organic matter (measured as TOC) was accumulated in the filter materials but was also released periodically. The results showed that Sorbulite could meet the demand in removing phosphate and nitrogen with reduced microbial release from the wastewater treatment process. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Improvement of cadmium ion removal by base treatment of juniper fiber

    Science.gov (United States)

    S.H. Min; J.S. Han; E.W. Shin; J.K. Park

    2004-01-01

    Juniper is a small-diameter underutilized lignocellulosic material. We evaluated the efficacy of base-treated juniper fiber (BTJF) for cadmium (Cd2+) sorption and the viability of juniper fiber as a sorbent for removing Cd2+ from water. Fourier transform infrared spectroscopy analysis indicated that carboxylate ion is a major functional group responsible for Cd2+...

  7. REMOVAL AND CONTAINMENT OF LEAD-BASED PAINT VIA NEEDLE SCALERS

    Science.gov (United States)

    This report describes a comparative technical and economic evaluation of using a dustless needlegun system versus a conventional abrasive grit blasting system in the removal of lead-based paint from steel structures. The objective of the study was to comparatively analyze the ope...

  8. FIELD DEMONSTRATION OF LEAD-BASED PAINT REMOVAL AND INORGANIC STABILIZATION TECHNOLOGIES

    Science.gov (United States)

    A study was conducted to demonstrate the effectiveness of a wet abrasive blasting technology to remove lead-based paint from exterior wood siding and brock substrates and to stabilize the resultant blasting media (coal slag and mineral sand) paint debris to reduce the leachable l...

  9. Clinical Fit of Partial Removable Dental Prostheses Based on Alginate or Polyvinyl Siloxane Impressions.

    NARCIS (Netherlands)

    Fokkinga, W.A.; Witter, D.J.; Bronkhorst, E.M.; Creugers, N.H.J.

    2017-01-01

    PURPOSE: The aim of this study was to analyze the clinical fit of metal-frame partial removable dental prostheses (PRDPs) based on custom trays used with alginate or polyvinyl siloxane impression material. MATERIALS AND METHODS: Fifth-year students of the Nijmegen Dental School made 25 correct

  10. A weak-base fibrous anion exchanger effective for rapid phosphate removal from water.

    Science.gov (United States)

    Awual, Md Rabiul; Jyo, Akinori; El-Safty, Sherif A; Tamada, Masao; Seko, Noriaki

    2011-04-15

    This work investigated that weak-base anion exchange fibers named FVA-c and FVA-f were selectively and rapidly taken up phosphate from water. The chemical structure of both FVA-c and FVA-f was the same; i.e., poly(vinylamine) chains grafted onto polyethylene coated polypropylene fibers. Batch study using FVA-c clarified that this preferred phosphate to chloride, nitrate and sulfate in neutral pH region and an equilibrium capacity of FVA-c for phosphate was from 2.45 to 6.87 mmol/g. Column study using FVA-f made it clear that breakthrough capacities of FVA-f were not strongly affected by flow rates from 150 to 2000 h(-1) as well as phosphate feed concentration from 0.072 to 1.6mM. Under these conditions, breakthrough capacities were from 0.84 to 1.43 mmol/g indicating high kinetic performances. Trace concentration of phosphate was also removed from feeds containing 0.021 and 0.035 mM of phosphate at high feed flow rate of 2500 h(-1), breakthrough capacities were 0.676 and 0.741 mmol/g, respectively. The column study also clarified that chloride and sulfate did not strongly interfere with phosphate uptake even in their presence of equimolar and fivefold molar levels. Adsorbed phosphate on FVA-f was quantitatively eluted with 1M HCl acid and regenerated into hydrochloride form simultaneously for next phosphate adsorption operation. Therefore, FVA-f is able to use long time even under rigorous chemical treatment of multiple regeneration/reuse cycles without any noticeable deterioration. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. An ontology-driven, case-based clinical decision support model for removable partial denture design

    Science.gov (United States)

    Chen, Qingxiao; Wu, Ji; Li, Shusen; Lyu, Peijun; Wang, Yong; Li, Miao

    2016-06-01

    We present the initial work toward developing a clinical decision support model for specific design of removable partial dentures (RPDs) in dentistry. We developed an ontological paradigm to represent knowledge of a patient’s oral conditions and denture component parts. During the case-based reasoning process, a cosine similarity algorithm was applied to calculate similarity values between input patients and standard ontology cases. A group of designs from the most similar cases were output as the final results. To evaluate this model, the output designs of RPDs for 104 randomly selected patients were compared with those selected by professionals. An area under the curve of the receiver operating characteristic (AUC-ROC) was created by plotting true-positive rates against the false-positive rate at various threshold settings. The precision at position 5 of the retrieved cases was 0.67 and at the top of the curve it was 0.96, both of which are very high. The mean average of precision (MAP) was 0.61 and the normalized discounted cumulative gain (NDCG) was 0.74 both of which confirmed the efficient performance of our model. All the metrics demonstrated the efficiency of our model. This methodology merits further research development to match clinical applications for designing RPDs. This paper is organized as follows. After the introduction and description of the basis for the paper, the evaluation and results are presented in Section 2. Section 3 provides a discussion of the methodology and results. Section 4 describes the details of the ontology, similarity algorithm, and application.

  12. Escherichia coli removal in biochar-augmented biofilter: effect of infiltration rate, initial bacterial concentration, biochar particle size, and presence of compost.

    Science.gov (United States)

    Mohanty, Sanjay K; Boehm, Alexandria B

    2014-10-07

    Bioretention systems and biofilters are used in low impact development to passively treat urban stormwater. However, these engineered natural systems are not efficient at removing fecal indicator bacteria, the contaminants responsible for a majority of surface water impairments. The present study investigates the efficacy of biochar-augmented model sand biofilters for Escherichia coli removal under a variety of stormwater bacterial concentrations and infiltration rates. Additionally, we test the role of biochar particle size and "presence of compost on model" biofilter performance. Our results show that E. coli removal in a biochar-augmented sand biofilter is ∼ 96% and is not greatly affected by increases in stormwater infiltration rates and influent bacterial concentrations, particularly within the ranges expected in field. Removal of fine (biochar particles from the biochar-sand biofilter decreased the removal capacity from 95% to 62%, indicating biochar size is important. Addition of compost to biochar-sand biofilters not only lowered E. coli removal capacity but also increased the mobilization of deposited bacteria during intermittent infiltration. This result is attributed to exhaustion of attachment sites on biochar by the dissolved organic carbon leached from compost. Overall, our study indicates that biochar has potential to remove bacteria from stormwater under a wide range of field conditions, but for biochar to be effective, the size should be small and biochar should be applied without compost. Although the results aid in the optimization of biofilter design, further studies are needed to examine biochar potential in the field over an entire rainy season.

  13. Azimuth Ambiguities Removal in Littoral Zones Based on Multi-Temporal SAR Images

    Directory of Open Access Journals (Sweden)

    Xiangguang Leng

    2017-08-01

    Full Text Available Synthetic aperture radar (SAR is one of the most important techniques for ocean monitoring. Azimuth ambiguities are a real problem in SAR images today, which can cause performance degradation in SAR ocean applications. In particular, littoral zones can be strongly affected by land-based sources, whereas they are usually regions of interest (ROI. Given the presence of complexity and diversity in littoral zones, azimuth ambiguities removal is a tough problem. As SAR sensors can have a repeat cycle, multi-temporal SAR images provide new insight into this problem. A method for azimuth ambiguities removal in littoral zones based on multi-temporal SAR images is proposed in this paper. The proposed processing chain includes co-registration, local correlation, binarization, masking, and restoration steps. It is designed to remove azimuth ambiguities caused by fixed land-based sources. The idea underlying the proposed method is that sea surface is dynamic, whereas azimuth ambiguities caused by land-based sources are constant. Thus, the temporal consistence of azimuth ambiguities is higher than sea clutter. It opens up the possibilities to use multi-temporal SAR data to remove azimuth ambiguities. The design of the method and the experimental procedure are based on images from the Sentinel data hub of Europe Space Agency (ESA. Both Interferometric Wide Swath (IW and Stripmap (SM mode images are taken into account to validate the proposed method. This paper also presents two RGB composition methods for better azimuth ambiguities visualization. Experimental results show that the proposed method can remove azimuth ambiguities in littoral zones effectively.

  14. Effect of application rates and media types on nitrogen and surfactant removal in trickling filters applied to the post-treatment of effluents from UASB reactors

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, P. G. S. de; Taveres, F. v. F.; Chernicharo, C. A. I.

    2009-07-01

    Tricking filters are a very promising alternative for the post treatment of effluents from UASB reactors treating domestic sewage,especially in developing countries. Although a fair amount of information is already available regarding organic mater removal in this combined system, very little is known in relation to nitrogen and surfactant removal in trickling filters post-UASB reactors. Therefore, the purpose of this study was to evaluate and compare the effect evaluate and compare the effect of different application rates and packing media types on trickling filters applied to the post-treatment of effluents from UASB reactors, regarding the removal of ammonia nitrogen and surfactants. (Author)

  15. A Range-Based Multivariate Model for Exchange Rate Volatility

    NARCIS (Netherlands)

    B. Tims (Ben); R.J. Mahieu (Ronald)

    2003-01-01

    textabstractIn this paper we present a parsimonious multivariate model for exchange rate volatilities based on logarithmic high-low ranges of daily exchange rates. The multivariate stochastic volatility model divides the log range of each exchange rate into two independent latent factors, which are

  16. Fuzzy Logic-Based Filter for Removing Additive and Impulsive Noise from Color Images

    Science.gov (United States)

    Zhu, Yuhong; Li, Hongyang; Jiang, Huageng

    2017-12-01

    This paper presents an efficient filter method based on fuzzy logics for adaptively removing additive and impulsive noise from color images. The proposed filter comprises two parts including noise detection and noise removal filtering. In the detection part, the fuzzy peer group concept is applied to determine what type of noise is added to each pixel of the corrupted image. In the filter part, the impulse noise is deducted by the vector median filter in the CIELAB color space and an optimal fuzzy filter is introduced to reduce the Gaussian noise, while they can work together to remove the mixed Gaussian-impulse noise from color images. Experimental results on several color images proves the efficacy of the proposed fuzzy filter.

  17. Applicability of Zeolite Based Systems for Ammonia Removal and Recovery From Wastewater.

    Science.gov (United States)

    Das, Pallabi; Prasad, Bably; Singh, Krishna Kant Kumar

    2017-09-01

      Ammonia discharged in industrial effluents bears deleterious effects and necessitates remediation. Integrated systems devoted to recovery of ammonia in a useful form and remediation of the same addresses the challenges of waste management and its utilization. A comparative performance evaluation study was undertaken to access the suitability of different zeolite based systems (commercial zeolites and zeolites synthesized from fly ash) for removal of ammonia followed by its subsequent release. Four main parameters which were studied to evaluate the applicability of such systems for large scale usage are cost-effectiveness, ammonia removal efficiency, performance on regeneration, and ammonia release percentage. The results indicated that synthetic zeolites outperformed zeolites synthesized from fly ash, although the later proved to be more efficient in terms of total cost incurred. Process technology development in this direction will be a trade-of between cost and ammonia removal and release efficiencies.

  18. Development of iron-based nanoparticles for Cr(VI removal from drinking water

    Directory of Open Access Journals (Sweden)

    Vourlias G.

    2013-01-01

    Full Text Available A great deal of research over recent decades has been motivated by the requirement to lower the concentration of chromium in drinking water. This study has been conducted to determine the feasibility of iron-based nanoparticles for chromium removal from contaminated water. Single Fe, Fe3O4 and binary Fe/Fe3O4 nanoparticles were grown at the 45-80 nm size range using the solar physical vapor deposition technique and tested as potential hexavalent chromium removing agents from aqueous solutions. Due to their higher electron donation ability compared to the Fe3O4 ones, single Fe nanoparticles exhibited the highest Cr(VI removal capacity of more than 3 µg/mg while maintaining a residual concentration 50 µg/L, equal to the regulation limit for drinking water. In combination to their facile and fast magnetic separation, the applicability of the studied particles in water treatment facilities should be considered.

  19. Automatic Artifact Removal from Electroencephalogram Data Based on A Priori Artifact Information

    Directory of Open Access Journals (Sweden)

    Chi Zhang

    2015-01-01

    Full Text Available Electroencephalogram (EEG is susceptible to various nonneural physiological artifacts. Automatic artifact removal from EEG data remains a key challenge for extracting relevant information from brain activities. To adapt to variable subjects and EEG acquisition environments, this paper presents an automatic online artifact removal method based on a priori artifact information. The combination of discrete wavelet transform and independent component analysis (ICA, wavelet-ICA, was utilized to separate artifact components. The artifact components were then automatically identified using a priori artifact information, which was acquired in advance. Subsequently, signal reconstruction without artifact components was performed to obtain artifact-free signals. The results showed that, using this automatic online artifact removal method, there were statistical significant improvements of the classification accuracies in both two experiments, namely, motor imagery and emotion recognition.

  20. Gaussian Elimination-Based Novel Canonical Correlation Analysis Method for EEG Motion Artifact Removal

    Directory of Open Access Journals (Sweden)

    Vandana Roy

    2017-01-01

    Full Text Available The motion generated at the capturing time of electro-encephalography (EEG signal leads to the artifacts, which may reduce the quality of obtained information. Existing artifact removal methods use canonical correlation analysis (CCA for removing artifacts along with ensemble empirical mode decomposition (EEMD and wavelet transform (WT. A new approach is proposed to further analyse and improve the filtering performance and reduce the filter computation time under highly noisy environment. This new approach of CCA is based on Gaussian elimination method which is used for calculating the correlation coefficients using backslash operation and is designed for EEG signal motion artifact removal. Gaussian elimination is used for solving linear equation to calculate Eigen values which reduces the computation cost of the CCA method. This novel proposed method is tested against currently available artifact removal techniques using EEMD-CCA and wavelet transform. The performance is tested on synthetic and real EEG signal data. The proposed artifact removal technique is evaluated using efficiency matrices such as del signal to noise ratio (DSNR, lambda (λ, root mean square error (RMSE, elapsed time, and ROC parameters. The results indicate suitablity of the proposed algorithm for use as a supplement to algorithms currently in use.

  1. Alginate-based nanocomposites for efficient removal of heavy metal ions.

    Science.gov (United States)

    Esmat, Mohamed; Farghali, Ahmed A; Khedr, Mohamed H; El-Sherbiny, Ibrahim M

    2017-09-01

    Cobalt ferrite nanoparticles (CF), titanate nanotubes (T), alginate (G) and their nanocomposite microparticles (CF/G and T/G) were prepared and used for efficient removal of Cu(2+), Fe(3+) and As(3+) ions from water. The nanocomposites were characterized using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), FTIR and vibrating sample magnetometer (VSM). In addition, the effects of pH, contact time, adsorbent weight and heavy metal ion concentration on the removal efficiency were investigated. Our results revealed a successful preparation of the nanocomposite particles. The optimized batch experiment conditions were found to be pH of 6.5, contact time of 2h and adsorbent weight of 0.15g. The removal efficiencies for Cu(2+) using G, CF, T, CF/G and T/G were found to be 91%, 100%, 99.9%, 95% and 98%, respectively. While that of Fe(3+) removal was 60%, 100%, 100%, 60% and 82%, respectively. Efficient removal of As(3+) ions was also attained (98% upon using T nanoadsorbents). The current study demonstrated that the developed nanomaterials (CF and T) and their corresponding alginate-based nanocomposite microparticles could be further tailored and used as efficient adsorbents for the uptake of different heavy metal ions from wastewater. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Colorimetric detection and removal of radioactive Co ions using sodium alginate-based composite beads

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Daigeun; Jo, Ara [Organic and Optoelectronic Materials Laboratory, Department of Organic Materials Engineering, Chungnam National University, Daejeon 34134 (Korea, Republic of); Yang, Hee-Man; Seo, Bum-Kyoung; Lee, Kune-Woo [Decontamination and Decommissioning Research Division, Korea Atomic Energy Research Institute, Daejeon 34057 (Korea, Republic of); Lee, Taek Seung, E-mail: tslee@cnu.ac.kr [Organic and Optoelectronic Materials Laboratory, Department of Organic Materials Engineering, Chungnam National University, Daejeon 34134 (Korea, Republic of)

    2017-03-15

    Highlights: • Organic/inorganic hybridized alginate beads were newly synthesized via sol-gel chemistry. • Interaction between the azopyridine and metal ion is the main cause of Co ion detection. • The beads showed improved stability and least leakage of azopyridine during use. • Removal of Co ion was assessed by the ion-exchange of carboxylate groups in alginate. • The beads with dual functions of detection and removal of Co ion were successfully accomplished. - Abstract: We demonstrate a simple method for the visual determination and removal of Co ions using a bead-shaped, capturing probe based on hybridized sodium alginate. For Co ions, the designed protocol consisted of three main constituents: an azopyridine-based Co ion-probe for visual detection; sodium alginate as an adsorbent for the Co ion and a bead construct for removal and structure; silica as a linker for the probe and the alginate, leading to a robust structure. When the composite beads were exposed to Co ions, the yellow color of the beads turned to intensive violet and the color intensity was associated with the Co ion concentration. The color variation was quantified using red-green-blue (RGB) color values that were obtained with a scanner and evaluated with Photoshop. The technique achieved both visual recognition with obvious color change of the beads and efficient removal of the radioactive {sup 60}Co ion. The sensing and removal of any radioactive isotope could be achieved with an appropriate sensing probe, to provide a simple and universal platform for remediation.

  3. Visual Sensor Based Abnormal Event Detection with Moving Shadow Removal in Home Healthcare Applications

    OpenAIRE

    Young-Sook Lee; Wan-Young Chung

    2012-01-01

    Vision-based abnormal event detection for home healthcare systems can be greatly improved using visual sensor-based techniques able to detect, track and recognize objects in the scene. However, in moving object detection and tracking processes, moving cast shadows can be misclassified as part of objects or moving objects. Shadow removal is an essential step for developing video surveillance systems. The goal of the primary is to design novel computer vision techniques that can extract objects...

  4. 76 FR 4569 - Market-Based Rate Affiliate Restrictions

    Science.gov (United States)

    2011-01-26

    ... Energy Regulatory Commission 18 CFR Part 35 Market-Based Rate Affiliate Restrictions AGENCY: Federal... proposed rulemaking, which proposed to amend its regulations governing market-based rates for public... clarification that employees that determine the timing of scheduled outages or that engage in economic dispatch...

  5. 75 FR 20796 - Market-Based Rate Affiliate Restrictions

    Science.gov (United States)

    2010-04-21

    ... Federal Energy Regulatory Commission 18 CFR Part 35 Market-Based Rate Affiliate Restrictions April 15... regulations governing market- based rates for public utilities pursuant to section 205 of the Federal Power Act (FPA). The Commission proposes to clarify that employees that determine the timing of scheduled...

  6. Base-Rate Neglect in ALCOVE: A Critical Reevaluation.

    Science.gov (United States)

    Lewandowsky, Stephan

    1995-01-01

    The recent hybrid model of categorization, Attention Learning Covering Map (ALCOVE), combines desirable properties of exemplar models with a connectionist architecture and learning rule. An important property is the apparent ability of ALCOVE to account for base-rate neglect. ALCOVE's base-rate neglect predictions are reexamined, and their…

  7. Experimental Study of Material Removal Rate in Electrical Discharge Turning of Titanium Alloy (Ti-6al-4v)

    Science.gov (United States)

    Puri, Y. M.; Gohil, Vikas

    2017-03-01

    Electrical discharge turning (EDT) is a new machining process in which an external axis is added to a conventional EDM machine in order to produce precise cylindrical forms on hard and difficult to machine materials. By feeding a pre shaped tool electrode against a rotating work piece, axially symmetrical pats can be produce. The machining performance of EDT process is influenced by its machining parameters, which directly affect the quality of the machined component. This paper presents an experimental study on the effects of EDM parameters namely pulse-on time, peak current, gap voltage, spindle speed and flushing pressure on material removal rate (MRR) in electrical discharge turning of titanium alloy Ti-6Al-4V. This has been done by means of the Taguchi’s design of experiment technique. A mathematical model has been developed for MRR by regression analysis and factor effects were analyzed using analysis of variance (ANOVA). Signal-to-noise ratio analysis is used to find the optimal condition.

  8. Interference-based optical image encryption with silhouette removal by amplitude modulation

    Science.gov (United States)

    Wang, Yong; Quan, Chenggen

    2017-10-01

    Interference-based optical encryption schemes have an inherent silhouette problem, due to the equipollent nature of the phase-only masks generated from an analytical method. We propose a new interference-based optical image encryption with silhouette removal by amplitude modulation. Different from the previous methods, which require time-consuming iterative computation or post-processing of the phase-only masks for silhouette removal, the proposed method can resolve the problem by adding an amplitude modulating operation on the original image. The introduction of the amplitude modulator can significantly enhance the security of the system, and the silhouette problem inherent in a conventional interference-based encryption method is fully resolved. The design and parameter choice of the amplitude modulator is discussed. Numerical simulations are presented to verify the validity of the proposed method.

  9. Novel silicone-based polymer containing active methylene designed for the removal of indoor formaldehyde.

    Science.gov (United States)

    Niu, Song; Yan, Hongxia

    2015-04-28

    Indoor air pollution is caused inevitably due to complicated home decoration, in which formaldehyde is one of the most typical pollutants. It will be a convenient, economical and effective strategy to remove indoor formaldehyde if imparting a feature of formaldehyde removal to decorative coatings. We have successfully explored a novel silicone-based polymer containing active methylene used as a formaldehyde absorbent in coatings via a straightforward transesterification process using inexpensive and easily available chemicals. The polymer has been characterized by (13)C NMR, FTIR, GC and GPC. Formaldehyde removal capacity of the coating films containing different contents of the polymer has been investigated. The results indicated that coatings incorporating 4wt% of the polymer could make the coating films exhibit significant improvement on formaldehyde removal including purificatory performance (>85%) and durability of purificatory effect (>60%), compared to those consisting of absorbents without any silicon, and improve yellowing resistance performance, while other properties, such as gloss, adhesion, pencil hardness, flexibility and impact resistance, were kept almost unaffected. The chemical absorption process of the silicone-based polymer filled in interior decorative coatings is demonstrated as a promising technology to purify indoor formaldehyde and thus can reduce the harm to individuals. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Regeneration of iron-based adsorptive media used for removing arsenic from groundwater.

    Science.gov (United States)

    Chen, Abraham S C; Sorg, Thomas J; Wang, Lili

    2015-06-15

    Adsorptive media technology is regarded as a simple, low cost method of removing arsenic from drinking water particularly for small systems. Currently, when the effluent of a treatment system reaches the USEPA maximum contaminant level (MCL) of 10 ug/L, the exhausted media is removed and replaced by new virgin media. Although the commonly used iron-based media products are reasonable in price, the replacement cost accounts for around 80% of the systems total operational costs. One option to media replacement is on-site regeneration and reuse of the exhausted media. To determine whether an iron based media can be successfully regenerated and reused, laboratory batch and column regeneration tests were conducted on six exhausted iron-based media products obtained from six full scale arsenic removal treatment systems. Batch tests conducted on three of the media products to evaluate the effectiveness of 1-6% caustic regenerant solutions found that arsenic desorption increased until around 4%. Using 4% caustic solutions, the columns tests on the six exhausted media products showed arsenic removals ranged from 25 to 90% with the best results obtained with the Severn Trent E33 media. Exposing the media to caustic (pH ≥ 13) and acid (pH ≤ 2) solutions found minimal media loss with the caustic solution, but significant media dissolution with a pH 2 acid solution. A six column pilot plant test at an Ohio test site with the lab regenerated media products found that the regenerated media could achieve arsenic removals somewhat similar to virgin media. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Comparative study of biological nutrient removal (BNR) processes with sedimentation and membrane-based separation.

    Science.gov (United States)

    Monti, Alessandro; Hall, Eric R; Dawson, Robert N; Husain, Hadi; Kelly, Harlan G

    2006-07-05

    A membrane-enhanced biological phosphorus removal (MEBPR) process was operated in parallel with a conventional EBPR (CEBPR) process under challenging operating conditions to uncover fundamental differences in their ability to remove chemical oxygen demand (COD), nitrogen (N), and phosphorus (P) from municipal wastewater. Both systems exhibited the same potential to achieve excellent soluble-P removal when a favorable COD to P ratio was maintained in the influent. The MEBPR train generated a superior effluent quality when measured as total P. The CEBPR effluent contained significantly lower levels of nitrates due to the extra denitrification occurring in the sludge blanket of the secondary clarifier. The observed sludge yield in the MEBPR system was estimated to be between 0.23 and 0.28 g VSS/g COD, and this was 15% lower than the CEBPR sludge yield. When the influent volatile fatty acids (VFAs) became limiting, the CEBPR train exhibited better performance in the removal of soluble-P, due to the higher observed sludge yield and an overall greater denitrification activity that led to a more efficient use of VFAs in the anaerobic zone. After experiencing a severe deterioration of the biological P activity in both processes, the MEBPR train exhibited faster recovery than the CEBPR side. In this experimental work, it was demonstrated that an MEBPR process can sustain long-term satisfactory bio-P performance at HRTs as low as 7 h. However, the lower sludge yield and the reduced denitrification capacity are two important factors that impact the design of high rate membrane-assisted biological nutrient removal (BNR) processes. (c) 2006 Wiley Periodicals, Inc.

  12. Evaluation of Team-Based Learning and Traditional Instruction in Teaching Removable Partial Denture Concepts.

    Science.gov (United States)

    Echeto, Luisa F; Sposetti, Venita; Childs, Gail; Aguilar, Maria L; Behar-Horenstein, Linda S; Rueda, Luis; Nimmo, Arthur

    2015-09-01

    The aim of this study was to evaluate the effectiveness of team-based learning (TBL) methodology on dental students' retention of knowledge regarding removable partial denture (RPD) treatment. The process of learning RPD treatment requires that students first acquire foundational knowledge and then use critical thinking skills to apply that knowledge to a variety of clinical situations. The traditional approach to teaching, characterized by a reliance on lectures, is not the most effective method for learning clinical applications. To address the limitations of that approach, the teaching methodology of the RPD preclinical course at the University of Florida was changed to TBL, which has been shown to motivate student learning and improve clinical performance. A written examination was constructed to compare the impact of TBL with that of traditional teaching regarding students' retention of knowledge and their ability to evaluate, diagnose, and treatment plan a partially edentulous patient with an RPD prosthesis. Students taught using traditional and TBL methods took the same examination. The response rate (those who completed the examination) for the class of 2013 (traditional method) was 94% (79 students of 84); for the class of 2014 (TBL method), it was 95% (78 students of 82). The results showed that students who learned RPD with TBL scored higher on the examination than those who learned RPD with traditional methods. Compared to the students taught with the traditional method, the TBL students' proportion of passing grades was statistically significantly higher (p=0.002), and 23.7% more TBL students passed the examination. The mean score for the TBL class (0.758) compared to the conventional class (0.700) was statistically significant with a large effect size, also demonstrating the practical significance of the findings. The results of the study suggest that TBL methodology is a promising approach to teaching RPD with successful outcomes.

  13. Evidence-based review of hair removal using lasers and light sources.

    Science.gov (United States)

    Haedersdal, M; Wulf, H C

    2006-01-01

    Unwanted hair growth remains a therapeutic challenge and there is a considerable need for an effective and safe treatment modality. From an evidence-based view to summarize efficacy and adverse effects from hair removal with ruby, alexandrite, diode, and Nd:YAG lasers and intense pulsed light (IPL). Original publications of controlled clinical trials were identified in Medline and the Cochrane Library. A total of 9 randomized controlled (RCTs) and 21 controlled trials (CTs) were identified. The best available evidence was found for the alexandrite (three RCTs, eight CTs) and diode (three RCTs, four CTs) lasers, followed by the ruby (two RCTs, six CTs) and Nd:YAG (two RCTs, four CTs) lasers, whereas limited evidence was available for IPL sources (one RCT, one CT). Based on the present best available evidence we conclude that (i) epilation with lasers and light sources induces a partial short-term hair reduction up to 6 months postoperatively, (ii) efficacy is improved when repeated treatments are given, (iii) efficacy is superior to conventional treatments (shaving, wax epilation, electrolysis), (iv) evidence exists for a partial long-term hair removal efficacy beyond 6 months postoperatively after repetitive treatments with alexandrite and diode lasers and probably after treatment with ruby and Nd:YAG lasers, whereas evidence is lacking for long-term hair removal after IPL treatment, (v) today there is no evidence for a complete and persistent hair removal efficacy, (vi) the occurrence of postoperative side-effects is reported low for all the laser systems. The evidence from controlled clinical trials favours the use of lasers and light sources for removal of unwanted hair. We recommend that patients are pre-operatively informed of the expected treatment outcome.

  14. The ability of biologically based wastewater treatment systems to remove emerging organic contaminants--a review.

    Science.gov (United States)

    Garcia-Rodríguez, Aida; Matamoros, Víctor; Fontàs, Clàudia; Salvadó, Victòria

    2014-10-01

    Biologically based wastewater treatment systems are considered a sustainable, cost-effective alternative to conventional wastewater treatment systems. These systems have been used and studied for the treatment of urban sewage from small communities, and recently, it has been reported that they can also effectively remove emerging organic contaminants (EOCs). EOCs are a new group of unregulated contaminants which include pharmaceutical and personal care products, some pesticides, veterinary products, and industrial compounds among others that are thought to have long-term adverse effects on human health and ecosystems. This review is focused on reporting the ability of biologically based wastewater treatment systems to remove EOCs and the main elimination mechanisms and degradation processes (i.e., biodegradation, photodegradation, phytoremediation, and sorption) taking place in constructed wetlands, ponds, and Daphnia and fungal reactors.

  15. Relationship among reaction rate, release rate and efficiency of nanomachine-based targeted drug delivery.

    Science.gov (United States)

    Zhao, Qingying; Li, Min; Luo, Jun

    2017-12-04

    In nanomachine applications towards targeted drug delivery, drug molecules released by nanomachines propagate and chemically react with tumor cells in aqueous environment. If the nanomachines release drug molecules faster than the tumor cells react, it will result in loss and waste of drug molecules. It is a potential issue associated with the relationship among reaction rate, release rate and efficiency. This paper aims to investigate the relationship among reaction rate, release rate and efficiency based on two drug reception models. We expect to pave a way for designing a control method of drug release. We adopted two analytical methods that one is drug reception process based on collision with tumors and another is based on Michaelis Menten enzymatic kinetics. To evaluate the analytical formulations, we used the well-known simulation framework N3Sim to establish simulations. The analytical results of the relationship among reaction rate, release rate and efficiency is obtained, which match well with the numerical simulation results in a 3-D environment. Based upon two drug reception models, the results of this paper would be beneficial for designing a control method of nanomahine-based drug release.

  16. Iron and aluminium based adsorption strategies for removing arsenic from water.

    Science.gov (United States)

    Giles, Dion E; Mohapatra, Mamata; Issa, Touma B; Anand, Shashi; Singh, Pritam

    2011-12-01

    Arsenic is a commonly occurring toxic metal in natural systems and is the root cause of many diseases and disorders. Occurrence of arsenic contaminated water is reported from several countries all over the world. A great deal of research over recent decades has been motivated by the requirement to lower the concentration of arsenic in drinking water and the need to develop low cost techniques which can be widely applied for arsenic removal from contaminated water. This review briefly presents iron and aluminium based adsorbents for arsenic removal. Studies carried out on oxidation of arsenic(III) to arsenic(V) employing various oxidising agents to facilitate arsenic removal are briefly mentioned. Effects of competing ions, As:Fe ratios, arsenic(V) vs. arsenic(III) removal using ferrihydrite as the adsorbent have been discussed. Recent efforts made for investigating arsenic adsorption on iron hydroxides/oxyhydroxides/oxides such as granular ferric hydroxide, goethite, akaganeite, magnetite and haematite have been reviewed. The adsorption behaviours of activated alumina, gibbsite, bauxite, activated bauxite, layered double hydroxides are discussed. Point-of-use adsorptive remediation methods indicate that Sono Arsenic filter and Kanchan™ Arsenic filter are in operation at various locations of Bangladesh and Nepal. The relative merits and demerits of such filters have been discussed. Evaluation of kits used for at-site arsenic estimation by various researchers also forms a part of this review. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Optimization of microwave-assisted rubberwood sawdust based activated carbon preparation conditions for methylene blue removal

    Science.gov (United States)

    Khasri, Azduwin; Ahmad, Mohd Azmier

    2017-10-01

    Optimum preparation conditions of rubberwood sawdust based activated carbon (RSAC) for methylene blue (MB) dye removal was studied. RSAC was produced by applying physiochemical activation method by using potassium hydroxide as a chemical agent which accompanied by carbon dioxide gasification under microwave heating. The effects of microwave power, irradiation time and impregnation ratio on two types of responses namely MB removal and RSAC yield using the center composite design (CCD) were also included in this study. The preparation variables correlation for responses was developed by two quadratic models. Optimum preparation conditions of RSAC were obtained at microwave power, irradiation time and IR of 354 W, 4.5 minutes and 0.98, respectively, which resulted MB removal and yield of 83.79% and 28%, respectively. The average pore diameter, surface area and total pore volume of optimized RSAC were 4.12 nm, 796.33 m2/g and 0.4219 cm3/g, respectively. This sample was found to has well-developed pores on its surface and can be a promising adsorbent for MB removal from aqueous solution.

  18. Fiber-based tools: material removal and mid-spatial frequency error reduction.

    Science.gov (United States)

    Shahinian, Hossein; Hassan, Mohammed; Cherukuri, Harish; Mullany, Brigid A

    2017-10-10

    This paper details the feasibility of using fiber-based tools in a computer numerical control (CNC) environment to process optical materials and their ability to reduce the amplitude of pre-existing mid-spatial-frequency (MSF) surface errors. The work is motivated by earlier research conducted by the group exploring the ability of polymeric fiber-based tools to remove material from BK7 glass substrates. To evaluate these tools in a CNC environment, three tasks are explored. First, the ability of the tools to maintain their form and material removal profile while operating under translational conditions is explored. Second, the ability of the tools to disengage and re-engage with the workpiece edge, and how this affects the tool's material removal profile. Finite element (FE) modelling of the fiber-workpiece edge interaction was conducted to support the experimental work. And third, the deterministic behavior of the tool under full raster conditions is verified. Testing on a 3-axis CNC machine tool demonstrated that the tooling is sufficiently robust and stable to operate under translational and rotational speeds of 30 mm/s and 1000 rpm, respectively. Both the FE modeling and experimental testing confirmed the truncation of a fiber's material removal profile as a fiber extends beyond the workpiece edge. The ability of fiber-based tools to reduce MSF errors was explored both through FE modeling and experimental testing on germanium samples. Both the FE model and experimental results demonstrate that fiber-based tools can successfully reduce pre-existing MSF errors.

  19. Web-Based Physician Ratings for California Physicians on Probation.

    Science.gov (United States)

    Murphy, Gregory P; Awad, Mohannad A; Osterberg, E Charles; Gaither, Thomas W; Chumnarnsongkhroh, Thanabhudee; Washington, Samuel L; Breyer, Benjamin N

    2017-08-22

     Web-based physician ratings systems are a popular tool to help patients evaluate physicians. Websites help patients find information regarding physician licensure, office hours, and disciplinary records along with ratings and reviews. Whether higher patient ratings are associated with higher quality of care is unclear.  The aim of this study was to characterize the impact of physician probation on consumer ratings by comparing website ratings between doctors on probation against matched controls.  A retrospective review of data from the Medical Board of California for physicians placed on probation from December 1989 to September 2015 was performed. Violations were categorized into nine types. Nonprobation controls were matched by zip code and specialty with probation cases in a 2:1 ratio using the California Department of Consumer Affairs website. Web-based reviews were recorded from vitals.com, healthgrades.com, and ratemds.com (ratings range from 1-5).  A total of 410 physicians were placed on probation for 866 violations. The mean (standard deviation [SD]) number of ratings per doctor was 5.2 (7.8) for cases and 4 (6.3) for controls (P=.003). The mean rating for physicians on probation was 3.7 (1.6) compared with 4.0 (1.0) for controls when all three rating websites were pooled (P1.0-2.2). This association was not significant in a multivariate model when we included age and gender.  Web-based physician ratings were lower for doctors on probation indicating that patients may perceive a difference. Despite these statistical findings, the absolute difference was quite small. Physician rating websites have utility but are imperfect proxies for competence. Further research on physician Web-based ratings is warranted to understand what they measure and how they are associated with quality.

  20. Pilot Plant Demonstration of Stable and Efficient High Rate Biological Nutrient Removal with Low Dissolved Oxygen Conditions

    Science.gov (United States)

    Aeration in biological nutrient removal (BNR) processes accounts for nearly half of the total electricity costs at many wastewater treatment plants. Even though conventional BNR processes are usually operated to have aerated zones with high dissolved oxygen (DO) concentrations, r...

  1. Heart rate-based lactate minimum test: a reproducible method.

    NARCIS (Netherlands)

    Strupler, M.; Muller, G.; Perret, C.

    2009-01-01

    OBJECTIVE: To find the individual intensity for aerobic endurance training, the lactate minimum test (LMT) seems to be a promising method. LMTs described in the literature consist of speed or work rate-based protocols, but for training prescription in daily practice mostly heart rate is used. The

  2. Rate adaptation in ad hoc networks based on pricing

    CSIR Research Space (South Africa)

    Awuor, F

    2011-09-01

    Full Text Available that incorporates penalty (pricing) obtruded to users’ choices of transmission parameters to curb the self-interest behaviour. Therefore users determine their data rates and transmit power based on the perceived coupled interference at the intended receiver...

  3. Six- and twelve-month documented removal rates among women electing postpartum inpatient compared to delayed or interval contraceptive implant insertions after Medicaid payment reform.

    Science.gov (United States)

    Crockett, Amy H; Pickell, Lesley Bundon; Heberlein, Emily C; Billings, Deborah L; Mills, Benjie

    2017-01-01

    This study aims to document 6- and 12-month removal rates for women receiving the contraceptive implant inpatient postpartum versus those receiving the same contraceptive method during an outpatient visit, in a setting where postpartum inpatient long-acting reversible contraceptive (LARC) services (devices plus provider insertion costs) are reimbursed by Medicaid. We conducted a retrospective cohort study among Medicaid-enrolled women using medical record review for all women receiving the etonogestrel implant between July 1, 2007 and June 30, 2014. We compared the percentage of women with the implant removed at 6 and 12 months as well as reasons for early removal, for inpatient postpartum implant insertions vs. delayed postpartum or interval outpatient implant insertions. A total of 4% of women (34/776 insertions) had documented implant removal within 6 months post-insertion, with no difference between postpartum inpatient and outpatient (delayed postpartum or interval). A total of 12% (62/518 insertions) of women had documented implant removal within 12 months. A lower percentage of women with postpartum inpatient insertions had the implant removed at 12 months post-insertion, compared to outpatient insertions (7% vs. 14%, p=.04). After controlling for age, parity, race and body mass index, women with postpartum inpatient insertions were less likely to have the implant removed within 12 months (OR=0.44, 95% CI 0.20-0.97). The most commonly stated reason for removal was abnormal uterine bleeding, regardless of insertion timing. In a setting with a Medicaid policy that covers postpartum inpatient LARC insertion, a low percentage of women who received an implant immediately postpartum had it removed within 1 year of insertion. A Medicaid payment policy that removes institutional barriers to offering postpartum inpatient contraceptive implants to women free-of-charge may facilitate meeting women's desires and intentions to delay subsequent pregnancy, as evidenced by

  4. Influence of pollution loading and flow rate on catalytic BTEX removal with a combined Cu2O, Fe0/Zeolite bed

    Directory of Open Access Journals (Sweden)

    Roohollah Rostami

    2014-01-01

    Full Text Available ABSTRACT Environmental impacts and health concerns of BTEX compounds have been pointed in many studies. The agencies responsible for health and environment have delivered standard and guideline for BTEX concentrations. Because of the extensive use in industries and the presence of these compounds in fossil fuels, their emission resources are very divers. Today's, Control of air pollution caused by these compounds is one of the air qualities controlling challenges. "Thermal catalyzed" process is one of the technologies to control this kind of air pollution and consistent with using nanoparticles as a catalyst, this process is further considered now. So, we conducted this study to survey elimination of the BTEX, form polluted air flow, by this process. In this study, removal of the BTEX from polluted air by a thermal catalyzed process in the presence of zero-valent iron and copper oxide nanoparticles was investigated and the effect of changes in pollution load and flow rate was surveyed on removal efficiency and the decomposition of the pollutants. Fe0 and Cu2O nanoparticles were coated on a bed of natural zeolite (Clinoptilolite with a zeolite grains size of 1-2 mm. The thermal catalyst process was conducted at 350°C and different pollution loading and air flow rate. 96.18% and 78.42% of removal efficiency achieved with the retention times of 14.1s and 7.05s. Increasing the pollution load reduced removal efficiency and pollutants' mineralization. By doubling the pollution load, the removal efficiency declined as much as 14.5 %. According to the results, increasing of the flow rate has a greater effect than the pollution load on the complete decomposition. Also this process showed a good efficiency for BTEX removal under high pollution loading and flow rates.

  5. Performance based regulation: a strategy to increase breastfeeding rates

    OpenAIRE

    Fernanda Cobo-Armijo; Sofía Charvel; Mauricio Hernández-Ávila

    2017-01-01

    The decreasing breastfeeding rate in México is of public health concern. In this paper we discus an innovative regulatory ap­proach -Performance Based Regulation- and its application to improve breastfeeding rates. This approach, forces industry to take responsibility for the lack of breastfeeding and its consequences. Failure to comply with this targets results in financial penalties. Applying performance based regulation as a strategy to improve breastfeeding is feasible because: the breast...

  6. Enhancing zero valent iron based natural organic matter removal by mixing with dispersed carbon cathodes.

    Science.gov (United States)

    Liu, Peng; Keller, Jurg; Gernjak, Wolfgang

    2016-04-15

    Former studies have shown that adding granular activated carbon (GAC) cathodes could enhance the overall performance of the zero valent iron (ZVI) process for organics removal. The present study evaluates for the first time the performance of such an enhanced ZVI process to remove natural organic matter (NOM), an important water quality parameter in drinking water. Lab-scale batch tests were conducted with surface reservoir feed water from a drinking water plant. In the GAC enhanced ZVI process dissolved organic carbon (DOC) and UV254 were reduced by 61±3% and 70±2%, respectively, during 24h treatment corresponding to 1.8min empty bed contact time. The process was superior to ZVI alone, particularly during the earlier stages of the process due to the synergistically increased iron dissolution rate. Besides GAC, graphite and anthracite also prove to be suitable and potentially more cost-effective options as cathode materials for the enhanced ZVI process, whereby electrically conductive graphite clearly outperformed anthracite. The dominant mechanisms in terms of NOM removal from surface water were found to be coagulation following iron dissolution and adsorption in the case of employing GAC. Oxidation was also occurring to a lesser degree, converting some non-biodegradable into biodegradable DOC. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Removal Rates of Dental Implants Placed in Conjunction With Autologous Bone and Xenogeneic and Synthetic Alloplastic Materials in Finland Between 1994 and 2012

    NARCIS (Netherlands)

    Wolff, J.; Pyysalo, M.; Antalainen, A.K.; Sandor, G.K.; Helminen, M.

    2015-01-01

    Purpose: This study aimed to assess the use of bone augmentation materials in Finland from 1994 to 2012 by assessing removal rates of implants placed in combination with autologous bone, xenogeneic grafts, and synthetic alloplastic materials. Materials and Methods: The National Institute for Health

  8. Removal rates of dental implants placed in conjunction with autologous bone and xenogeneic and synthetic alloplastic materials in Finland between 1994 and 2012

    NARCIS (Netherlands)

    Wolff, J.; Pyysalo, M.; Antalainen, A.K.; Sándor, G.K.; Helminen, M.

    2015-01-01

    Purpose: This study aimed to assess the use of bone augmentation materials in Finland from 1994 to 2012 by assessing removal rates of implants placed in combination with autologous bone, xenogeneic grafts, and synthetic alloplastic materials. Materials and Methods: The National Institute for Health

  9. 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...

  10. Reduced rate of intensive care unit acquired gram-negative bacilli after removal of sinks and introduction of 'water-free' patient care

    NARCIS (Netherlands)

    Hopman, J.; Tostmann, A.; Wertheim, H.F.L.; Bos, M.; Kolwijck, E.; Akkermans, R.P.; Sturm, P.D.J.; Voss, A.; Pickkers, P.; Hoeven, H. van der

    2017-01-01

    BACKGROUND: Sinks in patient rooms are associated with hospital-acquired infections. The aim of this study was to evaluate the effect of removal of sinks from the Intensive Care Unit (ICU) patient rooms and the introduction of 'water-free' patient care on gram-negative bacilli colonization rates.

  11. A reconsideration of negative ratings for network-based recommendation

    Science.gov (United States)

    Hu, Liang; Ren, Liang; Lin, Wenbin

    2018-01-01

    Recommendation algorithms based on bipartite networks have become increasingly popular, thanks to their accuracy and flexibility. Currently, many of these methods ignore users' negative ratings. In this work, we propose a method to exploit negative ratings for the network-based inference algorithm. We find that negative ratings play a positive role regardless of sparsity of data sets. Furthermore, we improve the efficiency of our method and compare it with the state-of-the-art algorithms. Experimental results show that the present method outperforms the existing algorithms.

  12. pH-sensitive Itaconic acid based polymeric hydrogels for dye removal applications.

    Science.gov (United States)

    Sakthivel, M; Franklin, D S; Guhanathan, S

    2016-12-01

    A series of Itaconic Acid (IA) based pH-sensitive polymeric hydrogels were synthesized by condensation polymerization of Itaconic Acid (IA) with Ethylene Glycol (EG) in the presence of an acid medium resulted into pre-polymer. Further, pre-polymer were co-polymerized with Acrylic Acid (AA) through free radical polymerization using Potassium persulphate (KPS). The structural and surface morphological characterizations of the synthesized hydrogels were studied using FT-IR spectroscopy and Scanning Electron Microscope (SEM) respectively. The swelling and swelling equilibrium were performed at varies pH (4.0-10.0). Further, the effects of IA, EG and AA on swelling properties have also been investigated. Thermal stability of synthesized hydrogels have been investigated by TGA, DTA and DSC. The synthesized hydrogels have shown good ability to uptake a Cationic dye. The Methylene blue has been chosen as a model cationic dye. The results of dye removal using IA hydrogels found to have excellent dye removal capacity. Such kind of IA based hydrogels may be recommended for eco-friendly environmental application. viz., removal of dyes and metal ions and sewage water treatment, purification of water etc. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. A High-Fidelity Haze Removal Method Based on HOT for Visible Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Hou Jiang

    2016-10-01

    Full Text Available Spatially varying haze is a common feature of most satellite images currently used for land cover classification and mapping and can significantly affect image quality. In this paper, we present a high-fidelity haze removal method based on Haze Optimized Transformation (HOT, comprising of three steps: semi-automatic HOT transform, HOT perfection and percentile based dark object subtraction (DOS. Since digital numbers (DNs of band red and blue are highly correlated in clear sky, the R-squared criterion is utilized to search the relative clearest regions of the whole scene automatically. After HOT transform, spurious HOT responses are first masked out and filled by means of four-direction scan and dynamic interpolation, and then homomorphic filter is performed to compensate for loss of HOT of masked-out regions with large areas. To avoid patches and halo artifacts, a procedure called percentile DOS is implemented to eliminate the influence of haze. Scenes including various land cover types are selected to validate the proposed method, and a comparison analysis with HOT and Background Suppressed Haze Thickness Index (BSHTI is performed. Three quality assessment indicators are selected to evaluate the haze removed effect on image quality from different perspective and band profiles are utilized to analyze the spectral consistency. Experiment results verify the effectiveness of the proposed method for haze removal and the superiority of it in preserving the natural color of object itself, enhancing local contrast, and maintaining structural information of original image.

  14. Fumarate-based metal-organic frameworks as a new platform for highly selective removal of fluoride from brick tea

    OpenAIRE

    Ke, Fei; Peng, Chuanyi; Zhang, Tian; Zhang, Mengran; Zhou, Chengyan; Cai, Huimei; Zhu, Junfa; Wan, Xiaochun

    2018-01-01

    Adsorption and removal of fluoride from brick tea is very important but challenging. In this work, two fumarate-based metal-organic frameworks (MOFs) were synthesized for the selective removal of fluoride from brick tea infusion. MOFs were examined for adsorption time, effect of dose, and uptake capacity at different initial concentrations and temperatures. Remarkably, over 80% fluoride removal was achieved by MOF-801 within 5 min at room temperature, while no significant adsorption occurred ...

  15. Coalescence-avoiding joint probabilistic data association based on bias removal

    Science.gov (United States)

    Jing, Peiliang; Xu, Shiyou; Li, Xian; Chen, Zengping

    2015-12-01

    In order to deal with the track coalescence problem of the joint probabilistic data association (JPDA) algorithm, a novel approach from a state bias removal point of view is developed in this paper. The factors that JPDA causes the state bias are analyzed, and the direct computation equation of the bias in the ideal case is given. Then based on the definitions of target detection hypothesis and target-to-target association hypothesis, the bias estimation is extended to the general and practical case. Finally, the estimated bias is removed from the state updated by JPDA to generate the unbiased state. The results of Monte Carlo simulations show that the proposed method can handle track coalescence and presents better performance when compared with the traditional methods.

  16. VLSI implementation of a new LMS-based algorithm for noise removal in ECG signal

    Science.gov (United States)

    Satheeskumaran, S.; Sabrigiriraj, M.

    2016-06-01

    Least mean square (LMS)-based adaptive filters are widely deployed for removing artefacts in electrocardiogram (ECG) due to less number of computations. But they posses high mean square error (MSE) under noisy environment. The transform domain variable step-size LMS algorithm reduces the MSE at the cost of computational complexity. In this paper, a variable step-size delayed LMS adaptive filter is used to remove the artefacts from the ECG signal for improved feature extraction. The dedicated digital Signal processors provide fast processing, but they are not flexible. By using field programmable gate arrays, the pipelined architectures can be used to enhance the system performance. The pipelined architecture can enhance the operation efficiency of the adaptive filter and save the power consumption. This technique provides high signal-to-noise ratio and low MSE with reduced computational complexity; hence, it is a useful method for monitoring patients with heart-related problem.

  17. A TBB-CUDA Implementation for Background Removal in a Video-Based Fire Detection System

    Directory of Open Access Journals (Sweden)

    Fan Wang

    2014-01-01

    Full Text Available This paper presents a parallel TBB-CUDA implementation for the acceleration of single-Gaussian distribution model, which is effective for background removal in the video-based fire detection system. In this framework, TBB mainly deals with initializing work of the estimated Gaussian model running on CPU, and CUDA performs background removal and adaption of the model running on GPU. This implementation can exploit the combined computation power of TBB-CUDA, which can be applied to the real-time environment. Over 220 video sequences are utilized in the experiments. The experimental results illustrate that TBB+CUDA can achieve a higher speedup than both TBB and CUDA. The proposed framework can effectively overcome the disadvantages of limited memory bandwidth and few execution units of CPU, and it reduces data transfer latency and memory latency between CPU and GPU.

  18. Dependence and risk assessment for oil prices and exchange rate portfolios: A wavelet based approach

    Science.gov (United States)

    Aloui, Chaker; Jammazi, Rania

    2015-10-01

    In this article, we propose a wavelet-based approach to accommodate the stylized facts and complex structure of financial data, caused by frequent and abrupt changes of markets and noises. Specifically, we show how the combination of both continuous and discrete wavelet transforms with traditional financial models helps improve portfolio's market risk assessment. In the empirical stage, three wavelet-based models (wavelet-EGARCH with dynamic conditional correlations, wavelet-copula, and wavelet-extreme value) are considered and applied to crude oil price and US dollar exchange rate data. Our findings show that the wavelet-based approach provides an effective and powerful tool for detecting extreme moments and improving the accuracy of VaR and Expected Shortfall estimates of oil-exchange rate portfolios after noise is removed from the original data.

  19. Rain-rate data base development and rain-rate climate analysis

    Science.gov (United States)

    Crane, Robert K.

    1993-01-01

    The single-year rain-rate distribution data available within the archives of Consultative Committee for International Radio (CCIR) Study Group 5 were compiled into a data base for use in rain-rate climate modeling and for the preparation of predictions of attenuation statistics. The four year set of tip-time sequences provided by J. Goldhirsh for locations near Wallops Island were processed to compile monthly and annual distributions of rain rate and of event durations for intervals above and below preset thresholds. A four-year data set of tropical rain-rate tip-time sequences were acquired from the NASA TRMM program for 30 gauges near Darwin, Australia. They were also processed for inclusion in the CCIR data base and the expanded data base for monthly observations at the University of Oklahoma. The empirical rain-rate distributions (edfs) accepted for inclusion in the CCIR data base were used to estimate parameters for several rain-rate distribution models: the lognormal model, the Crane two-component model, and the three parameter model proposed by Moupfuma. The intent of this segment of the study is to obtain a limited set of parameters that can be mapped globally for use in rain attenuation predictions. If the form of the distribution can be established, then perhaps available climatological data can be used to estimate the parameters rather than requiring years of rain-rate observations to set the parameters. The two-component model provided the best fit to the Wallops Island data but the Moupfuma model provided the best fit to the Darwin data.

  20. Novel sorbents for removal of gadolinium-based contrast agents in sorbent dialysis and hemoperfusion: preventive approaches to nephrogenic systemic fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Yantasee, Wassana; Fryxell, Glen E.; Porter, George A.; Pattamakomsan, Kanda; Sukwarotwat, Vichaya; Chouyyok, Wilaiwan; Koonsiripaiboon, View; Xu, Jide; Raymond, Kenneth N.

    2010-02-01

    Gd based contrast agents in many forms of organocomplex have recently been linked to a debilitating and a potentially fatal skin disease called Nephrogenic Systemic Fibrosis (NSF) in patients with renal failures. Free Gd released from the complexes by transmetallation is believed to be the most important trigger for NSF. Removal of Gd complex from the patients immediately after the contrast study would prevent the dissociation of Gd and should eliminate NSF as a complication. Although removal of Gd based contrast agents may be accomplished with conventional hemodialysis, it requires three hemodialysis sessions at 3 hours each to remove 98% of the contrast agents. In this work, mesoporous silica material that are functionalized with 1-hydroxy-2-pyridinone (1,2-HOPO-SAMMS®) has been evaluated for effective removal of both free and chelated Gd (Magnevist, a brand of gadopentetate dimeglumine) from the dialysate and sodium chloride solution. The material has high affinity, rapid removal rate, and large sorption capacity for both free and chelated Gd, the properties that are far superior to those of activated carbon and zirconium phosphate currently used in the state-of-the-art sorbent dialysis systems. 99% of both free and chelated Gd would be removed in a single pass thru the sorbent bed of 1,2-HOPO-SAMMS®. The sorbent provides an effective and predicable strategy for removing Gd from patients with impaired renal function, thus it would allow for the continued use of contrast MRI while removing the risk of NSF and would represent a safe alternative to traditional contrast studies in the patient population.

  1. Sequential Aeration of Membrane-Aerated Biofilm Reactors for High-Rate Autotrophic Nitrogen Removal: Experimental Demonstration

    DEFF Research Database (Denmark)

    Pellicer i Nàcher, Carles; Sun, Sheng-Peng; Lackner, Susanne

    2010-01-01

    One-stage autotrophic nitrogen (N) removal, requiring the simultaneous activity of aerobic and anaerobic ammonium oxidizing bacteria (AOB and AnAOB), can be obtained in spatially redox-stratified biofilms. However, previous experience with Membrane-Aerated Biofilm Reactors (MABRs) has revealed......S rRNA gene confirmed that sequential aeration, even at elevated average O2 loads, stimulated the abundance of AnAOB and AOB and prevented the increase in NOB. Nitrous oxide (N2O) emissions were 100-fold lower compared to other anaerobic ammonium oxidation (Anammox)-nitritation systems. Hence...... a difficulty in reducing the abundance and activity of nitrite oxidizing bacteria (NOB), which drastically lowers process efficiency. Here we show how sequential aeration is an effective strategy to attain autotrophic N removal in MABRs: Two separate MABRs, which displayed limited or no N removal under...

  2. Submicron and Nanoparticulate Matter Removal by HEPA-Rated Media Filters and Packed Beds of Granular Materials

    Science.gov (United States)

    Perry, J. L.; Agui, J. H.; Vijayakimar, R

    2016-01-01

    Contaminants generated aboard crewed spacecraft by diverse sources consist of both gaseous chemical contaminants and particulate matter. Both HEPA media filters and packed beds of granular material, such as activated carbon, which are both commonly employed for cabin atmosphere purification purposes have efficacy for removing nanoparticulate contaminants from the cabin atmosphere. The phenomena associated with particulate matter removal by HEPA media filters and packed beds of granular material are reviewed relative to their efficacy for removing fine (less than 2.5 micrometers) and ultrafine (less than 0.01 micrometers) sized particulate matter. Considerations are discussed for using these methods in an appropriate configuration to provide the most effective performance for a broad range of particle sizes including nanoparticulates.

  3. Production of sugarcane bagasse-based activated carbon for formaldehyde gas removal from potted plants exposure chamber.

    Science.gov (United States)

    Mohamed, Elham F; El-Hashemy, Mohammed A; Abdel-Latif, Nasser M; Shetaya, Waleed H

    2015-12-01

    Agricultural wastes such as rice straw, sugar beet, and sugarcane bagasse have become a critical environmental issue due to growing agriculture demand. This study aimed to investigate the valorization possibility of sugarcane bagasse waste for activated carbon preparation. It also aimed to fully characterize the prepared activated carbon (BET surface area) via scanning electron microscope (SEM) and in terms of surface functional groups to give a basic understanding of its structure and to study the adsorption capacity of the sugarcane bagasse-based activated carbon using aqueous methylene blue (MB). The second main objective was to evaluate the performance of sugarcane bagasse-based activated carbon for indoor volatile organic compounds removal using the formaldehyde gas (HCHO) as reference model in two potted plants chambers. The first chamber was labeled the polluted chamber (containing formaldehyde gas without activated carbon) and the second was taken as the treated chamber (containing formaldehyde gas with activated carbon). The results indicated that the sugarcane bagasse-based activated carbon has a moderate BET surface area (557 m2/g) with total mesoporous volume and microporous volume of 0.310 and 0.273 cm3/g, respectively. The prepared activated carbon had remarkable adsorption capacity for MB. Formaldehyde removal rate was then found to be more than 67% in the treated chamber with the sugarcane bagasse-based activated carbon. The plants' responses for this application as dry weight, chlorophyll contents, and protein concentration were also investigated. Preparation of activated carbon from sugarcane bagasse (SCBAC) is a promising approach to produce cheap and efficient adsorbent for gas pollutants removal. It may be also a solution for the agricultural wastes problems in big cities, particularly in Egypt. MB adsorption tests suggest that the SCBAC have high adsorption capacity. Formaldehyde gas removal in the plant chambers indicates that the SCBAC have

  4. Treatment of a slaughterhouse wastewater: effect of internal recycle rate on chemical oxygen demand, total Kjeldahl nitrogen and total phosphorus removal.

    Science.gov (United States)

    Fongsatitkul, P; Wareham, D G; Elefsiniotis, P; Charoensuk, P

    2011-12-01

    This study investigated the ability of an anaerobic/anoxic/oxic (A2/O) system to treat a slaughterhouse wastewater. The system employed two identical continuous-flow reactors (101 total liquid volume each) running in parallel with the main operational variable, being the internal recycle (IR) rate. The chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN) and total phosphorus (TP) performance was evaluated as the IR flowrate was increased from a Q of 151d(-1) to 4Q at a system hydraulic retention time of 16 h and a solids retention time of 10 d. The COD:TKN and COD:TP ratios were 8.2:1 and 54:1, which supported both nitrogen and phosphorus removal. For all IR multiples of Q, the COD removal was in excess of 90%. The TKN removal showed a modest improvement (a 4-5% increase, depending on the dissolved oxygen (DO)) as the IR doubled from Q to 2Q, but no further increase was observed at the 4Q IR rate. The TP removal reached its optimum (around 85%-89% (again depending on the DO)) at the 2Q rate.

  5. Comparing the Efficacy Rates of Lime and Poly Aluminum Chloride Coagulants in Cadmium Removal from the Landfill Leachate by Chemical Precipitation

    Directory of Open Access Journals (Sweden)

    Mostafaii Gh. PhD,

    2015-12-01

    Full Text Available Aims Chemical precipitation is a simple, efficient, and cost-effective method for eliminating heavy metals found in landfill leachate. The aim of the present study was to compare the efficacy rates of cadmium removal with the coagulants like poly aluminum chloride and lime using chemical precipitation method. Materials & Methods In this experimental study, the raw studied samples were collected from the landfill located in Kahrizak, Iran, in May 2014. The elimination rates of cadmium at 1000, 1500 and 2000mg/l concentrations of lime; at 100, 150 200mg/l concentrations of poly aluminum chloride; at 7, 9, 11 pH levels; and during 20, 40 and 60min of the reaction time were studied. Data were analyzed in SPSS 16 software using ANOVA, independent T and repeated measurement tests. Findings The maximum elimination rate of cadmium in both lime and poly aluminum chloride were seen at pH=11. The maximum rates of cadmium removal occurred at minute 40 in 2000mg/l concentration of lime (99.4% and 200mg/l concentration of poly aluminum chloride (98%. Conclusion Both lime and poly aluminum chloride have the best cadmium removal rate from leachate at pH=11 after 40 minutes of precipitation process. Being more inexpensive and easily available than poly aluminum chloride, lime is considered as an appropriate coagulant.

  6. Aluminum-based drinking-water treatment residuals: A novel sorbent for perchlorate removal

    Energy Technology Data Exchange (ETDEWEB)

    Makris, Konstantinos C. [Department of Earth and Environmental Science, University of Texas at San Antonio, 6900 North Loop 1604 West, San Antonio, TX 78249-0663 (United States); Sarkar, Dibyendu [Department of Earth and Environmental Science, University of Texas at San Antonio, 6900 North Loop 1604 West, San Antonio, TX 78249-0663 (United States)]. E-mail: dibyendu.sarkar@utsa.edu; Datta, Rupali [Department of Earth and Environmental Science, University of Texas at San Antonio, 6900 North Loop 1604 West, San Antonio, TX 78249-0663 (United States)

    2006-03-15

    Perchlorate contamination of aquifers and drinking-water supplies has led to stringent regulations in several states to reduce perchlorate concentrations in water at acceptable levels for human consumption. Several perchlorate treatment technologies exist, but there is significant cost associated with their use, and the majority of them are unable to degrade perchlorate to innocuous chloride. We propose the use of a novel sorbent for perchlorate, i.e. an aluminum-based drinking-water treatment residual (Al-WTR), which is a by-product of the drinking-water treatment process. Perchlorate sorption isotherms (23 {+-} 1 {sup o}C) showed that the greatest amount (65%) of perchlorate removed by the Al-WTR was observed with the lowest initial perchlorate load (10 mg L{sup -1}) after only 2 h of contact time. Increasing the contact time to 24 h, perchlorate removal increased from 65 to 76%. A significant correlation was observed between the amounts of perchlorate removed with evolved chloride in solution, suggesting degradation of perchlorate to chloride. - Drinking-water treatment residuals are a low-cost sorbent for perchlorate.

  7. High-accuracy process based on the corrective calibration of removal function in the magnetorheological finishing

    Science.gov (United States)

    Zhong, Xianyun; Fan, Bin; Wu, Fan

    2017-08-01

    The corrective calibration of the removal function plays an important role in the magnetorheological finishing (MRF) high-accuracy process. This paper mainly investigates the asymmetrical characteristic of the MRF removal function shape and further analyzes its influence on the surface residual error by means of an iteration algorithm and simulations. By comparing the ripple errors and convergence ratios based on the ideal MRF tool function and the deflected tool function, the mathematical models for calibrating the deviation of horizontal and flowing directions are presented. Meanwhile, revised mathematical models for the coordinate transformation of an MRF machine is also established. Furthermore, a Ø140-mm fused silica plane and a Ø196 mm, f/1∶1, fused silica concave sphere samples are taken as the experiments. After two runs, the plane mirror final surface error reaches PV 17.7 nm, RMS 1.75 nm, and the polishing time is 16 min in total; after three runs, the sphere mirror final surfer error reaches RMS 2.7 nm and the polishing time is 70 min in total. The convergence ratios are 96.2% and 93.5%, respectively. The spherical simulation error and the polishing result are almost consistent, which fully validate the efficiency and feasibility of the calibration method of MRF removal function error using for the high-accuracy subaperture optical manufacturing.

  8. Magnetic composites based on metallic nickel and molybdenum carbide: A potential material for pollutants removal

    Energy Technology Data Exchange (ETDEWEB)

    Mambrini, Raquel V.; Fonseca, Thales L. [Departamento de Quimica, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901 (Brazil); Dias, Anderson [Departamento de Quimica, Universidade Federal de Ouro Preto, Ouro Preto, MG 35400-000 (Brazil); Oliveira, Luiz C.A.; Araujo, Maria Helena [Departamento de Quimica, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901 (Brazil); Moura, Flavia C.C., E-mail: flaviamoura@ufmg.br [Departamento de Quimica, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901 (Brazil)

    2012-11-30

    Highlights: Black-Right-Pointing-Pointer New magnetic molybdenum carbide composites can be prepared by CVD from ethanol. Black-Right-Pointing-Pointer Magnetic molybdenum carbide shows promising results for pollutants removal. Black-Right-Pointing-Pointer The carbide composites can be easily recovered magnetically and reused. - Abstract: New magnetic composites based on metallic nickel and molybdenum carbide, Ni/Mo{sub 2}C, have been produced via catalytic chemical vapor deposition from ethanol. Scanning electron microscopy, thermal analysis, Raman spectroscopy and X-ray diffraction studies suggest that the CVD process occurs in a single step. This process involves the reduction of NiMo oxides at different temperatures (700, 800 and 900 Degree-Sign C) with catalytic deposition of carbon from ethanol producing molybdenum carbide on Ni surface. In the absence of molybdenum the formation of Ni/C was observed. The magnetic molybdenum carbide was successfully used as pollutants removal by adsorption of sulfur and nitrogen compounds from liquid fuels and model dyes such as methylene blue and indigo carmine. The dibenzothiofene adsorption process over Ni/Mo{sub 2}C reached approximately 20 mg g{sup -1}, notably higher than other materials described in the literature and also removed almost all methylene blue dye. The great advantage of these carbide composites is that they may be easily recovered magnetically and reused.

  9. Arduino-based noise robust online heart-rate detection.

    Science.gov (United States)

    Das, Sangita; Pal, Saurabh; Mitra, Madhuchhanda

    2017-04-01

    This paper introduces a noise robust real time heart rate detection system from electrocardiogram (ECG) data. An online data acquisition system is developed to collect ECG signals from human subjects. Heart rate is detected using window-based autocorrelation peak localisation technique. A low-cost Arduino UNO board is used to implement the complete automated process. The performance of the system is compared with PC-based heart rate detection technique. Accuracy of the system is validated through simulated noisy ECG data with various levels of signal to noise ratio (SNR). The mean percentage error of detected heart rate is found to be 0.72% for the noisy database with five different noise levels.

  10. Using wastewater and high-rate algal ponds for nutrient removal and the production of bioenergy and biofuels.

    Science.gov (United States)

    Batten, David; Beer, Tom; Freischmidt, George; Grant, Tim; Liffman, Kurt; Paterson, David; Priestley, Tony; Rye, Lucas; Threlfall, Greg

    2013-01-01

    This paper projects a positive outcome for large-scale algal biofuel and energy production when wastewater treatment is the primary goal. Such a view arises partly from a recent change in emphasis in wastewater treatment technology, from simply oxidising the organic matter in the waste (i.e. removing the biological oxygen demand) to removing the nutrients - specifically nitrogen and phosphorus - which are the root cause of eutrophication of inland waterways and coastal zones. A growing need for nutrient removal greatly improves the prospects for using new algal ponds in wastewater treatment, since microalgae are particularly efficient in capturing and removing such nutrients. Using a spreadsheet model, four scenarios combining algae biomass production with the making of biodiesel, biogas and other products were assessed for two of Australia's largest wastewater treatment plants. The results showed that super critical water reactors and anaerobic digesters could be attractive pathway options, the latter providing significant savings in greenhouse gas emissions. Combining anaerobic digestion with oil extraction and the internal economies derived from cheap land and recycling of water and nutrients on-site could allow algal oil to be produced for less than US$1 per litre.

  11. Microorganism and Agricultural Based Biosorbents Towards Removal of Cadmium from Waste-Water: An Overview.

    Science.gov (United States)

    Pal, Souvik; Mukherjee, Subhankar; Bhattacharyya, Nabarun

    2017-01-01

    Non-degradable and persistent nature of Cadmium (Cd) poses high toxicity to human, plants and animals. Several industrial processes generated wastes are the main anthropogenic pathway through which Cd enters into the environment. Although, World Health Organization (WHO) has set the limit of Cd in drinking water is 0.005 mg L-1, the industrial activities release much higher concentrations of metal ions to the water stream than the prescribed limits, which leads to the increasing health hazards and environmental pollution. To address this issue, one of the major applicable solutions is the treatment or purification of contaminated water and effluents. The implantation of wastewater treatment systems aims to minimize environmental impacts, but ultimately generates waste materials, such as sewage sludge, which must be properly recycled. In this review, we focus on the research efforts being made towards the removal of Cd (II) from waste waters using biological means with a special emphasis on the microorganism and agricultural based biosorbents. Mechanistic pathway towards removal of Cd (II) ions from the wastewater, efficiency of the adsorbents and the factors affecting the process have been studied with specific examples. Also the recent patents related to this area have been taken into considerations to understand applicability of microorganism and agricultural based biosorbents. This overview presents various scientific reports towards low-cost microorganism and agricultural based biosorbents for efficient removal of Cd (II) by producing less toxic waste and the future perspective of the process. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  12. Graphene and g-C3N4 based photocatalysts for NOx removal: A review

    Science.gov (United States)

    Nikokavoura, Aspasia; Trapalis, Christos

    2018-02-01

    NOx liberated into atmosphere from automobile exhausts and fossil fuel combustion, comprise the major air pollutants. They are responsible for serious environmental problems such as acid rain, ozone accumulation, haze and photochemical smog. Besides they contribute to the deterioration of human health by causing decrease of the lung function and respiratory problems. The application of photocatalytic methods in order to mitigate the presence of NOx in the atmosphere is preferable as they are environmentally friendly, mild and low cost. Therefore, in this review, the photocatalytic activity of g-C3N4 and graphene based composites towards NOx removal was discussed. NOx oxidation to non volatile nitrates on the surface of graphene and g-C3N4 based photocatalysts has attracted much interest during the last years due to their structures with unique features such as large specific surface area, thermal and chemical stability and enhanced visible light utilization. The formation of 2D-2D intimate heterojunctions between graphene or g-C3N4 and other components ensures the enhanced charge transfer, lifetime of electron/hole pairs and thus photocatalytic activity. The increased visible light harvesting also contributes to their usefulness as effective photocatalytic materials. In the present work, the advantages of these novel photocatalysts and the differences/similarities between them were exhaustively highlighted. The role of graphene as catalyst promoter, electron reservoir, support and photosensitizer in its photocatalytic composites was emphasized. The effect of g-C3N4 doping and copolymerization with metals/semiconductors on its photocatalytic activity towards NOx oxidation was thoroughly discussed. Besides, the preparation methods, photocatalytic efficiencies, type of irradiation, utilization of appropriate cocatalysts, and reaction mechanisms during the photocatalytic NOx removal by graphene and g-C3N4 composies, were summarized. It was demonstrated that in the vast

  13. Removal Kinetics of Organic Matter and Nitrogen Using Microbial Electrochemical Based - Constructed Wetlands (iMETland)

    DEFF Research Database (Denmark)

    Ramírez Vargas, Carlos Andrés; Arias, Carlos Alberto; Carvalho, Pedro

    In recent years the combination of Constructed Wetlands and Microbial Fuel Cell (MFC), has led to an innovative set- up for wastewater treatment and energy harvesting, relaying on electrodes and external circuits (CW – MFC). Based on this approach, a new concept is being developed to create....... The iMETland technology is still in development and therefore uncertainties still exist regarding the dynamics in the removal of pollutants, as well as in its performance along time. To elucidate these uncertainties, a benchmark study is being conducted to characterize the processes and interactions n...

  14. REMOVAL OF IMPULSIVE NOISE USING WEIGHTED FUZZY MEAN FILTER BASED ON CLOUD MODEL

    Directory of Open Access Journals (Sweden)

    K. Kannan

    2013-08-01

    Full Text Available This paper proposes a weighted fuzzy mean filter based on cloud model and reports its performance in removing the impulsive noise from the digital image. In addition, the performance of the proposed weighted fuzzy mean filter is compared with already existing variants of median and switching filters using root mean square error, peak signal to noise ratio and quality index. Even though the image is corrupted by 90%, this weighted fuzzy mean filter is capable of recovering the original image with good detail preservation.

  15. Novel Sorbent-Based Process for High Temperature Trace Metal Removal

    Energy Technology Data Exchange (ETDEWEB)

    Gokhan Alptekin

    2008-09-30

    intermittent operation of the PSDF gasifier (due to the difficulties in the handling of the low quality lignite), only a small fraction of the sorbent capacity was utilized (we measured a mercury capacity of 3.27 mg/kg, which is only a fraction of the 680 mg/kg Hg capacity measured for the same sorbent used at our bench-scale evaluations at TDA). Post reaction examination of the sorbent by chemical analysis also indicated some removal As and Se (we did not detect any significant amounts of Cd in the synthesis gas or over the sorbent). The tests at UNDEERC was more successful and showed clearly that the TDA sorbent can effectively remove Hg and other trace metals (As and Se) at high temperature. The on-line gas measurements carried out by TDA and UNDEERC separately showed that TDA sorbent can achieve greater than 95% Hg removal efficiency at 260 C ({approx}200g sorbent treated more than 15,000 SCF synthesis gas). Chemical analysis conducted following the tests also showed modest amounts of As and Se accumulation in the sorbent bed (the test durations were still short to show higher capacities to these contaminants). We also evaluated the stability of the sorbent and the fate of mercury (the most volatile and unstable of the trace metal compounds). The Synthetic Ground Water Leaching Procedure Test carried out by an independent environmental laboratory showed that the mercury will remain on the sorbent once the sorbent is disposed. Based on a preliminary engineering and cost analysis, TDA estimated the cost of mercury removal from coal-derived synthesis gas as $2,995/lb (this analysis assumes that this cost also includes the cost of removal of all other trace metal contaminants). The projected cost will result in a small increase (less than 1%) in the cost of energy.

  16. Poultry litter-based activated carbon for removing heavy metal ions in water.

    Science.gov (United States)

    Guo, Mingxin; Qiu, Guannan; Song, Weiping

    2010-02-01

    Utilization of poultry litter as a precursor material to manufacture activated carbon for treating heavy metal-contaminated water is a value-added strategy for recycling the organic waste. Batch adsorption experiments were conducted to investigate kinetics, isotherms, and capacity of poultry litter-based activated carbon for removing heavy metal ions in water. It was revealed that poultry litter-based activated carbon possessed significantly higher adsorption affinity and capacity for heavy metals than commercial activated carbons derived from bituminous coal and coconut shell. Adsorption of metal ions onto poultry litter-based carbon was rapid and followed Sigmoidal Chapman patterns as a function of contact time. Adsorption isotherms could be described by different models such as Langmuir and Freundlich equations, depending on the metal species and the coexistence of other metal ions. Potentially 404 mmol of Cu2+, 945 mmol of Pb2+, 236 mmol of Zn2+, and 250-300 mmol of Cd2+ would be adsorbed per kg of poultry litter-derived activated carbon. Releases of nutrients and metal ions from litter-derived carbon did not pose secondary water contamination risks. The study suggests that poultry litter can be utilized as a precursor material for economically manufacturing granular activated carbon that is to be used in wastewater treatment for removing heavy metals.

  17. Flexible Thermoplastic Denture Base Materials for Aesthetical Removable Partial Denture Framework

    OpenAIRE

    Singh, Kunwarjeet; Aeran, Himanshu; Kumar, Narender; Gupta, Nidhi

    2013-01-01

    Conventional fixed partial dentures, implant supported Fixed Partial Dentures (FDPs) and removable partial dentures are the most common treatment modalities for the aesthetic and functional rehabilitation of partially edentulous patients. Although implants and FDP have certain advantages over removable partial dentures, in some cases, removable partial dentures may be the only choice which is available. Removable cast partial dentures are used as definitive removable prostheses when indicated...

  18. Coupled interference based rate adaptation in ad hoc networks

    CSIR Research Space (South Africa)

    Awuor, F

    2011-09-01

    Full Text Available since the channel condition is time variant [5], [6]. Hence CIN considers link adaptation based on SINR performance to derive transmit power that minimizes coupled interference in the network. In [5], an algorithm is proposed where an average value... channel condition variance for proper choice of PHY mode. In [7], rate adaptation scheme is proposed wherein nodes select the power-rate pair to maximize their utility based on the previous measured SINRs. The values of SINR employed by [5],[6] and [7...

  19. The Effect of Removing Potentially Infectious Dogs on the Numbers of Canine Leishmania infantum Infections in an Endemic Area with High Transmission Rates

    Science.gov (United States)

    Grimaldi, Gabriel; Teva, Antonio; Santos, Claudiney B.; Ferreira, Adelson L.; Falqueto, Aloísio

    2012-01-01

    To assess the effect of the rapid removal of potentially infectious dogs on the prevalence and incidence of canine infections, a prospective study was undertaken in an area endemic for Leishmania infantum. We used serological testing based on the rapid DPP rK28 fusion protein chromatographic immunoassay for this dog screening-and-culling intervention trial. The outcome was evaluated by measuring seropositivity and sero-conversion/-reversion rates for canine infection. Our estimates indicated that concomitant detection and elimination of seropositive dogs with active disease may affect the numbers of canine infections and disease burden temporarily, although it is insufficient as a measure to interrupt the zoonotic L. infantum transmission. However, most of the asymptomatic, seropositive dogs continuously exhibit low levels of antibodies and/or reverted, remaining seronegative thereafter. In the process of waiting for an effective vaccine, one option for canine reservoir control may be to identify these possibly genetically resistant animals and promote their expansion in the population. PMID:22665602

  20. Improving the ablation efficiency of excimer laser systems with higher repetition rates through enhanced debris removal and optimized spot pattern.

    Science.gov (United States)

    Arba-Mosquera, Samuel; Klinner, Thomas

    2014-03-01

    To evaluate the reasons for the required increased radiant exposure for higher-repetition-rate excimer lasers and determine experimentally possible compensations to achieve equivalent ablation profiles maintaining the same single-pulse energies and radiant exposures for laser repetition rates ranging from 430 to 1000 Hz. Schwind eye-tech-solutions GmbH and Co. KG, Kleinostheim, Germany. Experimental study. Poly(methyl methacrylate) (PMMA) plates were photoablated. The pulse laser energy was maintained during all experiments; the effects of the flow of the debris removal, the shot pattern for the correction, and precooling the PMMA plates were evaluated in terms of achieved ablation versus repetition rate. The mean ablation performance ranged from 88% to 100%; the variability between the profile measurements ranged from 1.4% to 6.2%. Increasing the laser repetition rate from 430 Hz to 1000 Hz reduced the mean ablation performance from 98% to 91% and worsened the variability from 1.9% to 4.3%. Increasing the flow of the debris removal, precooling the PMMA plates to -18°C, and adapting the shot pattern for the thermal response of PMMA to excimer ablation helped stabilize the variability. Only adapting the shot pattern for the thermal response of PMMA to excimer ablation helped stabilize the mean ablation performance. The ablation performance of higher-repetition-rate excimer lasers on PMMA improved with improvements in the debris removal systems and shot pattern. More powerful debris removal systems and smart shot patterns in terms of thermal response improved the performance of these excimer lasers. Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  1. Human trafficking for organ removal in India: a victim-centered, evidence-based report.

    Science.gov (United States)

    Budiani-Saberi, Debra A; Raja, Kallakurichi Rajendiran; Findley, Katie C; Kerketta, Ponsian; Anand, Vijay

    2014-02-27

    Enhancements in the national transplant law to prohibit commercial transplants in India have curbed the trade. Yet, the human rights abuse of human trafficking for organ removal (HTOR) continues in various transplant centers throughout India. Beginning in September 2010 until May 2012, in-depth interviews were conducted with 103 victims of HTOR in India in which victims described their experiences of a commercial kidney removal in compelling detail. Victims were located in Tamil Nadu, and reference is made to the broader study that included 50 additional victims in small towns and villages in West Bengal and Karnataka. Fourteen cases (14%) in Tamil Nadu and an additional 20 cases (40%) from West Bengal and Karnataka occurred between 2009 to May 2012. The cases in Tamil Nadu ranged in age from 19 to 55 years, with an average age of 33 years in Erode and 36 years in Chennai. Fifty-seven percent of the victims in Erode are female, and 87% of the victims in Chennai are female. Twelve percent of the individuals were widowed or abandoned, 79% were married, and 91% were parents with an average of two kids. Of those interviewed, 28% had no formal education, 19% had some primary schooling, 22% had some secondary schooling, and no individuals reported schooling above high school. All victims interviewed lived in abject poverty with monthly income levels well below the national average. The majority of victims reported long lasting health, economic, social, and psychological consequences. No matter the reason expressed for an organ sale, all victims reported that they would not have agreed to the organ removal if their economic circumstances were not so dire. One hundred percent of the victims interviewed expressed that they need assistance to cope with these consequences. Human trafficking for an organ removal continues in private transplant centers throughout India, service to foreign patients is ongoing, and victims' consequences are long lasting. A rights-based response

  2. A DO- and pH-Based Early Warning System of Nitrification Inhibition for Biological Nitrogen Removal Processes

    Science.gov (United States)

    Hong, Seil; Choi, Il; Lim, Byung Jin; Kim, Hyunook

    2012-01-01

    In Korea, more than 80% of municipal wastewater treatment plants (WWTPs) with capacities of 500 m3·d−1 or more are capable of removing nitrogen from wastewater through biological nitrification and denitrification processes. Normally, these biological processes show excellent performance, but if a toxic chemical is present in the influent to a WWTP, the biological processes (especially, the nitrification process) may be affected and fail to function normally; nitrifying bacteria are known very vulnerable to toxic substances. Then, the toxic compound as well as the nitrogen in wastewater may be discharged into a receiving water body without any proper treatment. Moreover, it may take significant time for the process to return back its normal state. In this study, a DO- and pH-based strategy to identify potential nitrification inhibition was developed to detect early the inflow of toxic compounds to a biological nitrogen removal process. This strategy utilizes significant changes observed in the oxygen uptake rate and the pH profiles of the mixed liquor when the activity of nitrifying bacteria is inhibited. Using the strategy, the toxicity from test wastewater with 2.5 mg·L−1 Hg2+, 0.5 mg·L−1 allythiourea, or 0.25 mg·L−1 chloroform could be successfully detected. PMID:23443381

  3. Preparation of Fly ash Based Adsorbents for Removal Active Red X-3B from Dying Wastewater

    Directory of Open Access Journals (Sweden)

    Li Jinping

    2016-01-01

    Full Text Available Fly ash with a large number of active sites can occur with the adsorbent chemical and physical adsorption, and therefore have a strong adsorption capacity. The original fly ash and raw fly ash compared to the physical and chemical properties to a significant change. On the fly ash in industrial water treatment application were outlined. The purpose is to focus on the modification methods of fly ash and comparison of raw fly ash and fly ash in the effect of dyeing wastewater. Single factor test method; select the appropriate modifier to study the dosage, pH, stirring time on the modification of adsorption properties of fly ash before and after. The results showed that the modified fly ash was better than the adsorption. Greatly improves on active red X-3B dye wastewater removal capacity, pH = 5, 6, dosage is 5g / L, the mixing time is 30min, COD removal rate reached 73.07%. This modified material can be used as adsorbent for pre-treating dying wastewater.

  4. A study on the effects of different hydraulic loading rates (HLR) on pollutant removal efficiency of subsurface horizontal-flow constructed wetlands used for treatment of domestic wastewaters.

    Science.gov (United States)

    Çakir, Recep; Gidirislioglu, Ali; Çebi, Ulviye

    2015-12-01

    The research into the treatment of domestic wastewaters originating from Büyükdöllük village in Edirne Province was carried out over a 3 year experimental period. The wastewaters of the settlement were treated using a constructed wetland with subsurface horizontal flow, and the effects of different hydraulic loading levels on removal efficiency were studied. In order to achieve this goal, three equal chambers (ponds) of 300 m(2) each were constructed and planted with Phragmites australis. Each of the chambers was loaded with domestic wastewater with average flow discharge creating hydraulic loading rates of 0. m(3) day(-1) m(-2); 0.075 m(3) day(-1) m(-2) and 0.125 m(3) day(-1) m(-2), respectively. According to the results of the study, the inlet levels of the pollutant parameters with carbon origin in the water samples taken from the system entrance are high and the average values for three years are respectively: Biological Oxygen Demand, BOD5 -324.5 mg L(-1); Chemical Oxygen Demand, COD -484,0 mg L(-1); suspended solids (TSS) -147.3 mg L(-1) and Oil and Grease -0.123 mg L(-1). It was also determined that the removal rates of the system were closely dependent on the applied hydraulic loading levels and the highest removal rates of 64.9%, 62.5%, 86.3% and 80.34% for BOD5, COD, TSS and Oil and Grease, respectively, were determined in the pond with a hydraulic loading rate of 0.050 m(3) day(-1) m(-2). Lower removal of 57.9%, 55.5%, 81.4% and 74.5% for BOD5, COD, TSS and Oil and Grease were recorded in the pond with a hydraulic loading rate of 0.075 m(3) day(-1) m(-2); and these values were 49.1%, 47.8%, 70.9% and 62.1% for the pond with a hydraulic loading rate of 0.125 m(3) day(-1) m(-2). High removal rates were also recorded for the other investigated pollution parameters. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. A Pilot-scale Evaluation of Soluble Manganese Removal Using Pyrolucite Media in a High-Rate Adsorptive Contactor

    OpenAIRE

    Subramaniam, Archana

    2010-01-01

    Soluble manganese (Mn) is a common water contaminant which can cause discoloration of water and staining if not treated properly in a water treatment plant. The â natural greensand effectâ is one of the proven methods for efficient removal of Mn from water. Therefore, research is ongoing to develop different ways to effectively create the natural greensand effect in a post-filtration sorptive contactor for application at water treatment facilities. The research reported by Zuravnsky (...

  6. Pilot plant demonstration of stable and efficient high rate biological nutrient removal with low dissolved oxygen conditions.

    Science.gov (United States)

    Keene, Natalie A; Reusser, Steve R; Scarborough, Matthew J; Grooms, Alan L; Seib, Matt; Santo Domingo, Jorge; Noguera, Daniel R

    2017-09-15

    Aeration in biological nutrient removal (BNR) processes accounts for nearly half of the total electricity costs at many wastewater treatment plants. Even though conventional BNR processes are usually operated to have aerated zones with high dissolved oxygen (DO) concentrations, recent research has shown that nitrification can be maintained using very low-DO concentrations (e.g., below 0.2 mg O2/L), and therefore, it may be possible to reduce energy use and costs in BNR facilities by decreasing aeration. However, the effect of reduced aeration on enhanced biological phosphorus removal (EBPR) is not understood. In this study, we investigated, at the pilot-scale level, the effect of using minimal aeration on the performance of an EBPR process. Over a 16-month operational period, we performed stepwise decreases in aeration, reaching an average DO concentration of 0.33 mg O2/L with stable operation and nearly 90% phosphorus removal. Under these low-DO conditions, nitrification efficiency was maintained, and nearly 70% of the nitrogen was denitrified, without the need for internal recycling of high nitrate aeration basin effluent to the anoxic zone. At the lowest DO conditions used, we estimate a 25% reduction in energy use for aeration compared to conventional BNR operation. Our improved understanding of the efficiency of low-DO BNR contributes to the global goal of reducing energy consumption during wastewater treatment operations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Agent-based model of laser hair removal: a treatment optimization and patient education tool.

    Science.gov (United States)

    Eapen, Bell Raj

    2009-01-01

    Tracking of various parameters associated with laser hair removal is tedious and time consuming. The currently available mathematical models are not simple enough for physicians to be used as a treatment optimization and patient education tool. The aim of the study was to develop a mathematical model for laser hair removal using agent-based modeling and to make a user-friendly simulation environment. The model was created using NetLogo. The hairs were modeled as agents oscillating between anagen and telogen. The variables were assigned based on published data whenever possible and the various paths the agent could take were coded as conditional statements. The improvement was assessed using an arbitrary index which takes into account the mean diameter and pigmentation along with the number and length of hairs visible above the surface. Few of the commonly encountered scenarios were simulated using the model. The model is made freely available online (http://www.gulfdoctor.net/model/lhr.htm). Limited number of simulations performed indicated that an eight-week gap between laser sessions may be more effective than a four-week gap. The simulation provides a reliable tool for treatment optimization and patient education as obtaining relevant clinical data is slow and labor-intensive. Its visual interface and online availability makes it useful for everyday use.

  8. Agent-based model of laser hair removal: A treatment optimization and patient education tool

    Directory of Open Access Journals (Sweden)

    Eapen Bell

    2009-01-01

    Full Text Available Background: Tracking of various parameters associated with laser hair removal is tedious and time consuming. The currently available mathematical models are not simple enough for physicians to be used as a treatment optimization and patient education tool. Aim: The aim of the study was to develop a mathematical model for laser hair removal using agent-based modeling and to make a user-friendly simulation environment. Methods: The model was created using NetLogo. The hairs were modeled as agents oscillating between anagen and telogen. The variables were assigned based on published data whenever possible and the various paths the agent could take were coded as conditional statements. The improvement was assessed using an arbitrary index which takes into account the mean diameter and pigmentation along with the number and length of hairs visible above the surface. Few of the commonly encountered scenarios were simulated using the model. Results: The model is made freely available online (http://www.gulfdoctor.net/model/lhr.htm. Limited number of simulations performed indicated that an eight-week gap between laser sessions may be more effective than a four-week gap. Conclusions: The simulation provides a reliable tool for treatment optimization and patient education as obtaining relevant clinical data is slow and labor-intensive. Its visual interface and online availability makes it useful for everyday use.

  9. Tuning of Isomerization Rates in Indigo-Based Photoswitches

    Science.gov (United States)

    Samoylova, E.; Maerz, B.; Wiedbrauk, S.; Oesterling, S.; Nenov, A.; Dube, H.; de Vivie-Riedle, R.; Zinth, W.

    Ultrafast excited-state dynamics in indigo-based photochromic compounds was studied with the transient absorption spectroscopy and ab initio calculations. We demonstrate an approach for adjusting excited state relaxation routes and photoisomerization rates for applications where fast photoswitching is needed.

  10. Research on the Material Removal in the Polishing of Potassium Dihydrogen Phosphate Crystals Based on Deliquescent Action

    Directory of Open Access Journals (Sweden)

    Shaolong Guo

    2014-01-01

    Full Text Available Through the polishing experiments of potassium dihydrogen phosphate (KDP crystals based on deliquescent action, the effect of several major factors, including crystal’s initial surface state, polishing time, and revolution of polishing plate, on material removal was researched. Under certain experimental conditions, the rules of material removal were reached, and experimental results are discussed, which lays the foundation for popularization and application of polishing technology for KDP crystals based on deliquescent action.

  11. Removal of Phenolic Compounds from Water Using Sewage Sludge-Based Activated Carbon Adsorption: A Review

    Science.gov (United States)

    Jarrah, Nabeel; Zubair, Mukarram; Alagha, Omar

    2017-01-01

    Due to their industrial relevance, phenolic compounds (PC) are amongst the most common organic pollutants found in many industrial wastewater effluents. The potential detrimental health and environmental impacts of PC necessitate their removal from wastewater to meet regulatory discharge standards to ensure meeting sustainable development goals. In recent decades, one of the promising, cost-effective and environmentally benign techniques for removal of PC from water streams has been adsorption onto sewage sludge (SS)-based activated carbon (SBAC). This is attributed to the excellent adsorptive characteristics of SBAC and also because the approach serves as a strategy for sustainable management of huge quantities of different types of SS that are in continual production globally. This paper reviews conversion of SS into activated carbons and their utilization for the removal of PC from water streams. Wide ranges of topics which include SBAC production processes, physicochemical characteristics of SBAC, factors affecting PC adsorption onto SBAC and their uptake mechanisms as well as the regeneration potential of spent SBAC are covered. Although chemical activation techniques produce better SBAC, yet more research work is needed to harness advances in material science to improve the functional groups and textural properties of SBAC as well as the low performance of physical activation methods. Studies focusing on PC adsorptive performance on SBAC using continuous mode (that are more relevant for industrial applications) in both single and multi-pollutant aqueous systems to cover wide range of PC are needed. Also, the potentials of different techniques for regeneration of spent SBAC used for adsorption of PC need to be assessed in relation to overall economic evaluation within realm of environmental sustainability using life cycle assessment. PMID:28934127

  12. Removal of Phenolic Compounds from Water Using Sewage Sludge-Based Activated Carbon Adsorption: A Review.

    Science.gov (United States)

    Mu'azu, Nuhu Dalhat; Jarrah, Nabeel; Zubair, Mukarram; Alagha, Omar

    2017-09-21

    Due to their industrial relevance, phenolic compounds (PC) are amongst the most common organic pollutants found in many industrial wastewater effluents. The potential detrimental health and environmental impacts of PC necessitate their removal from wastewater to meet regulatory discharge standards to ensure meeting sustainable development goals. In recent decades, one of the promising, cost-effective and environmentally benign techniques for removal of PC from water streams has been adsorption onto sewage sludge (SS)-based activated carbon (SBAC). This is attributed to the excellent adsorptive characteristics of SBAC and also because the approach serves as a strategy for sustainable management of huge quantities of different types of SS that are in continual production globally. This paper reviews conversion of SS into activated carbons and their utilization for the removal of PC from water streams. Wide ranges of topics which include SBAC production processes, physicochemical characteristics of SBAC, factors affecting PC adsorption onto SBAC and their uptake mechanisms as well as the regeneration potential of spent SBAC are covered. Although chemical activation techniques produce better SBAC, yet more research work is needed to harness advances in material science to improve the functional groups and textural properties of SBAC as well as the low performance of physical activation methods. Studies focusing on PC adsorptive performance on SBAC using continuous mode (that are more relevant for industrial applications) in both single and multi-pollutant aqueous systems to cover wide range of PC are needed. Also, the potentials of different techniques for regeneration of spent SBAC used for adsorption of PC need to be assessed in relation to overall economic evaluation within realm of environmental sustainability using life cycle assessment.

  13. Evidence-based considerations for removable prosthodontic and dental implant occlusion: a literature review.

    Science.gov (United States)

    Taylor, Thomas D; Wiens, Jonathan; Carr, Alan

    2005-12-01

    The dental literature is filled with discussions of dental occlusion, occlusal schemes, philosophies, and methods to correct and restore the diseased, worn, or damaged occlusion. Traditionally, these discussions have been empirical in nature and not based on scientific evidence. Due to the empirical nature of the literature, the study of occlusion has been extremely complex and troublesome to both pre- and post-doctoral students. The introduction of osseointegrated implants has further complicated the situation. Dentists may apply the principles of occlusion for the natural dentition directly to implant-supported and retained restorations. Although this may be successful, this rationale may result in overly complex or simplified treatment protocols and outcomes. There is an emerging body of scientific literature related to dental implant therapy that may be useful in formulating treatment protocols and prosthesis designs for implant-supported restorations. This review focuses on some of the "classic" removable prosthodontic literature and the currently available scientific literature involving removable prosthodontic occlusion and dental implant occlusion. The authors reviewed the English peer-reviewed literature prior to 1996 in as comprehensive manner as possible, and material after 1996 was reviewed electronically using MEDLINE. Electronic searches of the literature were performed in MEDLINE using key words-animal studies, case series, clinical trials, cohort studies, complete denture occlusion, dental implant function, dental implant occlusion, dental implant occlusion research, dental implant functional loading, dental implants, dental occlusion, dental occlusion research, denture function, denture occlusion, dentures, implant function, implant functional loading, implant occlusion, occlusion, and removable partial denture occlusion-in various combinations to obtain potential references for review. A total of 5447 English language titles were obtained, many of

  14. A Personal Perspective on the Initial Federal Health-Based Regulation to Remove Lead from Gasoline

    Science.gov (United States)

    Bridbord, Kenneth; Hanson, David

    2009-01-01

    Objective This article describes the personal experience and perspective of the authors, who had primary responsibility for drafting the initial health-based regulation limiting lead content of gasoline during the early 1970s while employed by the U.S. Environmental Protection Agency (EPA). Data source Information used by the U.S. EPA in developing the initial health-based regulation limiting lead content of gasoline in December 1973 and studies documenting the impact of that and subsequent actions. Data extraction Among the lessons learned from this experience is the importance of having input from independent scientists to the regulatory decision-making process. This also demonstrates the critical role of independent peer-reviewed research, such as that supported by the National Institutes of Health, as well as research conducted by scientists from the Centers for Disease Control and Prevention, in delineating the consequences of lead exposure in the population. Data synthesis Removal of lead from gasoline in the United States has been described as one of the great public health achievements of the 20th century, but it almost did not happen. The experience of the authors in developing this regulation may be helpful to others involved in developing health-based regulatory policy in the future. Conclusion The initial U.S. EPA health-based regulation to remove lead from gasoline is clearly an example where science successfully affected public policy. The leadership of the U.S. EPA at that time deserves much credit for establishing an atmosphere in which this was possible. PMID:19672397

  15. Removal of As, Cd, Cr, Cu, Ni and Zn from polluted water using an iron based sorbent

    DEFF Research Database (Denmark)

    Genc-Fuhrman, Hülya; Wu, P.; Zhou, Y.

    2008-01-01

    In this study fixed-bed sorption filters are filled with an iron based sorbent (ferrosorp plus, FP) and used to remove a range of heavy metals (i.e. As, Cd, Cr, Cu, Ni, and Zn) from polluted water. It is found that FP is very effective at simultaneous removal of the heavy metals, and the magnitude...... of heavy metal removal in a decreasing order is Cd, Ni, Cr, Zn, Cu and As. Furthermore, the effect of humic acid (HA) and light on the heavy metal removal is also tested. The data show that both the presence of 100 mg/L HA and the absence of light suppress the removal, with the suppression due to HA being...

  16. Artificial-intelligence-based optimization of the management of snow removal assets and resources.

    Science.gov (United States)

    2002-10-01

    Geographic information systems (GIS) and artificial intelligence (AI) techniques were used to develop an intelligent : snow removal asset management system (SRAMS). The system has been evaluated through a case study examining : snow removal from the ...

  17. ANALYZE OF THE TURBIDITY REMOVAL RATE IN NATURAL WATERS BY THE USE OF THE EXTRACT OF MORINGA OLEIFERA LAM SEEDS

    Directory of Open Access Journals (Sweden)

    Luana Loren Corrêa Oliveira

    2011-07-01

    Full Text Available New methodologies of water and wastewater treatment pointed out the use of natural products instead the use of conventional chemical reactants. On this scene, natural extracts has been prepared using seeds of Moringa oleifera for alternative water cleaning, in regions without conventional treatment. In this kind of research, essentials variables such as extract resting time or dilution for example, plays an important role for improving the efficiency of the tests. In this work, the study of the water Turbidity removal was performed using different extract preparations and the tests showed a direct link between these variables to improve the water clarification process.

  18. A macroalgae-based biotechnology for water remediation: Simultaneous removal of Cd, Pb and Hg by living Ulva lactuca.

    Science.gov (United States)

    Henriques, Bruno; Rocha, Luciana S; Lopes, Cláudia B; Figueira, Paula; Duarte, A C; Vale, Carlos; Pardal, M A; Pereira, E

    2017-04-15

    Metal uptake from contaminated waters by living Ulva lactuca was studied during 6 days, under different relevant contamination scenarios. In mono-metallic solutions, with concentrations ranging from 10 to 100 μg L-1 for Hg, 10-200 μg L-1 for Cd, and 50-1000 μg L-1 for Pb, macroalgae (500 mg L-1, d.w.) were able to remove, in most cases 93-99% of metal, allowing to achieve water quality criteria regarding both surface and drinking waters. In multi-metallic solutions, comprising simultaneously the three metals, living macroalgae still performed well, with Hg removal (c.a. 99%) not being significantly affected by the presence of Cd and Pb, even when those metals were in higher concentrations. Removal efficiencies for Cd and Pb varied between 57 and 96%, and 34-97%, respectively, revealing an affinity of U. lactuca toward metals: Hg > Cd > Pb. Chemical quantification in macroalgae, after bioaccumulation assays demonstrated that all Cd and Hg removed from solution was really bound in macroalgae biomass, while only half of Pb showed to be sorbed on the biomass. Overall, U. lactuca accumulated up to 209 μg g-1 of Hg, up to 347 μg g-1 of Cd and up to 1641 μg g-1 of Pb, which correspond to bioconcentration factors ranging from 500 to 2200, in a dose-dependent accumulation. Pseudo-first order, pseudo-second order and Elovich models showed a good performance in describing the kinetics of bioaccumulation, in the whole period of time. In the range of experimental conditions used, no mortality was observed and U. lactuca relative growth rate was not significantly affected by the presence of metals. Results represent an important contribution for developing a macroalgae-based biotechnology, applied for contaminated saline water remediation, more "green" and cost-effective than conventional treatment methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Development of Composite Adsorbent Coating Based Acrylic Polymer/Bentonite for Methylene Blue Removal

    Directory of Open Access Journals (Sweden)

    Syahida Farhan Azha

    2017-07-01

    Full Text Available The development of composite adsorbent coating based acrylic polymer solution (APS mixed with bentonite (ben was investigated. The composite adsorbent coating was prepared and coated to a high surface area substrate, cotton cellulosic fiber (CCF. The APS/ben-CCF was used for a single cationic methylene blue (MB dye adsorption system. Characterization of composition and structure of materials and coating was carried out by X-ray fluorescence (XRF, scanning electron microscopy (SEM, and UV-spectroscopy (UV-VIS. The adsorption properties of the APS/ben-CCF were investigated as a function of solution pH, initial dye concentration and contact time as well as solution temperature of MB dye. The result revealed that the APS/ben-CCF functioned well in solutions of various pH (acidic to alkaline, achieving 100% removal of MB within 2 hours of adsorption for 50 ppm. Kinetic studies showed that APS/ben-CCF is endothermic in nature since the adsorption capacity increased with increasing solution temperature. These results demonstrate that APS/ben-CCF composite adsorbent coating is an advanced adsorbent with advantages such as easy phase separation and capability to remove cationic dyes in a short time period.

  20. Electrochemical treatment of rice grain-based distillery effluent: chemical oxygen demand and colour removal.

    Science.gov (United States)

    Prajapati, Abhinesh Kumar; Chaudhari, Parmesh Kumar

    2014-01-01

    The electrochemical (EC) treatment of rice grain-based distillery wastewater was carried out in a 1.5 dm3 electrolytic batch reactor using aluminium plate electrodes. With the four-plate configurations, a current density (j) of 89.3 A/m2 and pH 8 was found to be optimal, obtaining a maximum chemical oxygen demand (COD) and colour removal of 93% and 87%, respectively. The chemical dissolution of aluminium was strongly influenced by initial pH (pHi). At higher pHi (pH 9.5) anode consumption decreased while energy consumption increased. At the optimal current density 89.3 A/m2, the aluminium electrode consumption was 16.855 g/dm3 wastewater and energy consumption was 31.4 Wh/dm3 achieving a maximum COD removal of 87%. The settling and filterability characteristics ofelectrochemically treated sludge were also analysed at different pH. It was noted that treated slurry at pHi 9.5 gave best settling characteristic, which decreased with increase in pH. EC-treated effluent at pHi 8 had provided best filterability. Characteristics of scum and residues are also analysed at different pH.

  1. Magnetic composites based on metallic nickel and molybdenum carbide: a potential material for pollutants removal.

    Science.gov (United States)

    Mambrini, Raquel V; Fonseca, Thales L; Dias, Anderson; Oliveira, Luiz C A; Araujo, Maria Helena; Moura, Flávia C C

    2012-11-30

    New magnetic composites based on metallic nickel and molybdenum carbide, Ni/Mo(2)C, have been produced via catalytic chemical vapor deposition from ethanol. Scanning electron microscopy, thermal analysis, Raman spectroscopy and X-ray diffraction studies suggest that the CVD process occurs in a single step. This process involves the reduction of NiMo oxides at different temperatures (700, 800 and 900°C) with catalytic deposition of carbon from ethanol producing molybdenum carbide on Ni surface. In the absence of molybdenum the formation of Ni/C was observed. The magnetic molybdenum carbide was successfully used as pollutants removal by adsorption of sulfur and nitrogen compounds from liquid fuels and model dyes such as methylene blue and indigo carmine. The dibenzothiofene adsorption process over Ni/Mo(2)C reached approximately 20 mg g(-1), notably higher than other materials described in the literature and also removed almost all methylene blue dye. The great advantage of these carbide composites is that they may be easily recovered magnetically and reused. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Polysulfone and polyacrylate-based zwitterionic coatings for the prevention and easy removal of marine biofouling.

    Science.gov (United States)

    Hibbs, Michael R; Hernandez-Sanchez, Bernadette A; Daniels, Justin; Stafslien, Shane J

    2015-01-01

    A series of polysulfone and polyacrylate-based zwitterionic coatings were prepared on epoxy-primed aluminum substrata and characterized for their antifouling (AF) and fouling-release (FR) properties towards marine bacteria, microalgae and barnacles. The zwitterionic polymer coatings provided minimal resistance against bacterial biofilm retention and microalgal cell attachment, but facilitated good removal of attached microbial biomass by exposure to water-jet apparatus generated hydrodynamic shearing forces. Increasing the ion content of the coatings improved the AF properties, but required a stronger adhesive bond to the epoxy-primed aluminum substratum to prevent coating swelling and dissolution. Grafted poly(sulfobetaine) (gpSBMA), the most promising zwitterionic coating identified from microfouling evaluations, enabled the removal of four out of five barnacles reattached to its surface without incurring damage to their baseplates. This significant result indicated that gpSBMA relied predominately on its surface chemistry for its FR properties since it was very thin (~1-2 µm) relative to commercial coating standards (>200 µm).

  3. SVM-Based Spectral Analysis for Heart Rate from Multi-Channel WPPG Sensor Signals

    Directory of Open Access Journals (Sweden)

    Jiping Xiong

    2017-03-01

    Full Text Available Although wrist-type photoplethysmographic (hereafter referred to as WPPG sensor signals can measure heart rate quite conveniently, the subjects’ hand movements can cause strong motion artifacts, and then the motion artifacts will heavily contaminate WPPG signals. Hence, it is challenging for us to accurately estimate heart rate from WPPG signals during intense physical activities. The WWPG method has attracted more attention thanks to the popularity of wrist-worn wearable devices. In this paper, a mixed approach called Mix-SVM is proposed, it can use multi-channel WPPG sensor signals and simultaneous acceleration signals to measurement heart rate. Firstly, we combine the principle component analysis and adaptive filter to remove a part of the motion artifacts. Due to the strong relativity between motion artifacts and acceleration signals, the further denoising problem is regarded as a sparse signals reconstruction problem. Then, we use a spectrum subtraction method to eliminate motion artifacts effectively. Finally, the spectral peak corresponding to heart rate is sought by an SVM-based spectral analysis method. Through the public PPG database in the 2015 IEEE Signal Processing Cup, we acquire the experimental results, i.e., the average absolute error was 1.01 beat per minute, and the Pearson correlation was 0.9972. These results also confirm that the proposed Mix-SVM approach has potential for multi-channel WPPG-based heart rate estimation in the presence of intense physical exercise.

  4. Region filling and object removal by exemplar-based image inpainting.

    Science.gov (United States)

    Criminisi, Antonio; Pérez, Patrick; Toyama, Kentaro

    2004-09-01

    A new algorithm is proposed for removing large objects from digital images. The challenge is to fill in the hole that is left behind in a visually plausible way. In the past, this problem has been addressed by two classes of algorithms: 1) "texture synthesis" algorithms for generating large image regions from sample textures and 2) "inpainting" techniques for filling in small image gaps. The former has been demonstrated for "textures"--repeating two-dimensional patterns with some stochasticity; the latter focus on linear "structures" which can be thought of as one-dimensional patterns, such as lines and object contours. This paper presents a novel and efficient algorithm that combines the advantages of these two approaches. We first note that exemplar-based texture synthesis contains the essential process required to replicate both texture and structure; the success of structure propagation, however, is highly dependent on the order in which the filling proceeds. We propose a best-first algorithm in which the confidence in the synthesized pixel values is propagated in a manner similar to the propagation of information in inpainting. The actual color values are computed using exemplar-based synthesis. In this paper, the simultaneous propagation of texture and structure information is achieved by a single, efficient algorithm. Computational efficiency is achieved by a block-based sampling process. A number of examples on real and synthetic images demonstrate the effectiveness of our algorithm in removing large occluding objects, as well as thin scratches. Robustness with respect to the shape of the manually selected target region is also demonstrated. Our results compare favorably to those obtained by existing techniques.

  5. Novel Integration of Frame Rate Up Conversion and HEVC Coding Based on Rate-Distortion Optimization.

    Science.gov (United States)

    Lu, Guo; Zhang, Xiaoyun; Chen, Li; Gao, Zhiyong

    2018-02-01

    Frame rate up conversion (FRUC) can improve the visual quality by interpolating new intermediate frames. However, high frame rate videos by FRUC are confronted with more bitrate consumption or annoying artifacts of interpolated frames. In this paper, a novel integration framework of FRUC and high efficiency video coding (HEVC) is proposed based on rate-distortion optimization, and the interpolated frames can be reconstructed at encoder side with low bitrate cost and high visual quality. First, joint motion estimation (JME) algorithm is proposed to obtain robust motion vectors, which are shared between FRUC and video coding. What's more, JME is embedded into the coding loop and employs the original motion search strategy in HEVC coding. Then, the frame interpolation is formulated as a rate-distortion optimization problem, where both the coding bitrate consumption and visual quality are taken into account. Due to the absence of original frames, the distortion model for interpolated frames is established according to the motion vector reliability and coding quantization error. Experimental results demonstrate that the proposed framework can achieve 21% ~ 42% reduction in BDBR, when compared with the traditional methods of FRUC cascaded with coding.

  6. Overnight storage of removable dentures in alkaline peroxide-based tablets affects biofilm mass and composition.

    Science.gov (United States)

    Duyck, J; Vandamme, K; Muller, P; Teughels, W

    2013-12-01

    Clinical guidelines for denture care are available, but evidence for optimal nocturnal storage is scarce. The aim of the study was to compare the role of the overnight storage state on plaque growth and composition on acrylic removable dentures. In a parallel-group randomized controlled trial of 51 institutionalized participants, 3 denture overnight preservation methods were considered: (i) in water, (ii) dry or (iii) in water with added alkaline peroxide-based cleansing tablet. Biofilm samples were taken on day 7 (developing biofilm - dBF) and day 14 (maturing biofilm - mBF) from a mechanically uncleaned, standardized region, situated distally to the second lower premolars. Total and individual levels of selected perio-pathogenic and commensal species (n=20), and of Candida albicans were calculated by PCR. Differences between storage conditions (water/dry/tablet) and between the samples (dBF/mBF) were assessed by means of unpaired and paired t-tests respectively, with α=5%. Overnight denture storage with cleansing tablet significantly decreased the total bacterial level of dBF and mBF up to 13.8%. Fn, Ec, Cs, Sc, Ao and Vp counts were particularly affected by tablet care. Significant lower amounts of Candida albicans for tablet storage compared to water preservation were recorded in dBF and mBF (-69.3 ± 3.8% and -75.9 ± 3.2% respectively). The mass and pathogenicity of dBF and mBF was equal, irrespective of the overnight storage intervention. The use of cleansing tablets for acrylic removable denture overnight storage reduces denture biofilm mass and pathogenicity compared to dry and water preservation, and may contribute to the overall systemic health. Evidence-based clinical guidelines for overnight storage of removable acrylic dentures are lacking. The findings of this study indicate that alkaline peroxide-based cleansing tablets decrease bacterial and Candida levels in denture biofilms in case of poor oral hygiene. This provides evidence for a clinical

  7. Clinical Fit of Partial Removable Dental Prostheses Based on Alginate or Polyvinyl Siloxane Impressions.

    Science.gov (United States)

    Fokkinga, Wietske A; Witter, Dick J; Bronkhorst, Ewald M; Creugers, Nico H

    The aim of this study was to analyze the clinical fit of metal-frame partial removable dental prostheses (PRDPs) based on custom trays used with alginate or polyvinyl siloxane impression material. Fifth-year students of the Nijmegen Dental School made 25 correct impressions for 23 PRDPs for 21 patients using alginate, and 31 correct impressions for 30 PRDPs for 28 patients using polyvinyl siloxane. Clinical fit of the framework as a whole and of each retainer separately were evaluated by calibrated supervisors during framework try-in before (first evaluation) and after (second evaluation) possible adjustments (score 0 = poor fit, up to score 3 = good fit). Framework fit and fit of the denture base were evaluated at delivery (third evaluation). Finally, postinsertion sessions were evaluated and total number of sessions needed, sore spots, adjustments to the denture base, and reported food-impaction were recorded. No significant differences in clinical fit (of the framework as a whole, for the retainers, or for the denture base) were found between the groups in the three evaluation sessions. Differences were not found for postinsertion sessions with one exception: in the alginate group, four subjects reported food impaction, versus none in the polyvinyl siloxane group. Clinical fit of metal-frame PRDPs based on impressions with custom trays combined with alginate or polyvinyl siloxane was similar.

  8. Impact of implant support on mandibular free-end base removable partial denture: theoretical study.

    Science.gov (United States)

    Oh, Won-suk; Oh, Tae-Ju; Park, Ju-mi

    2016-02-01

    This study investigated the impact of implant support on the development of shear force and bending moment in mandibular free-end base removable partial dentures (RPDs). Three theoretical test models of unilateral mandibular free-end base RPDs were constructed to represent the base of tooth replacement, as follows: Model 1: first and second molars (M1 and M2); Model 2: second premolar (P2), M1, and M2; and Model 3: first premolar (P1), P2, M1, and M2. The implant support located either at M1 or M2 sites. The occlusal loading was concentrated at each replacement tooth to calculate the stress resultants developed in the RPD models using the free-body diagrams of shear force and bending moment. There was a trend of reduction in the peak shear force and bending moment when the base was supported by implant. However, the degree of reduction varied with the location of implant support. The moment reduced by 76% in Model 1, 58% in Model 2, and 42% in Model 3, when the implant location shifted from M1 to M2 sites. The shear forces and bending moments subjected to mandibular free-end base RPDs were found to decrease with the addition of implant support. However, the impact of implant support varied with the location of implant in this theoretical study. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Removal of microcystin-LR from drinking water using a bamboo-based charcoal adsorbent modified with chitosan.

    Science.gov (United States)

    Zhang, Hangjun; Zhu, Guoying; Jia, Xiuying; Ding, Ying; Zhang, Mi; Gao, Qing; Hu, Ciming; Xu, Shuying

    2011-01-01

    A new kind of low-cost syntactic adsorbent from bamboo charcoal and chitosan was developed for the removal of microcystin-LR from drinking water. Removal efficiency was higher for the syntactic adsorbent when the amount of bamboo charcoal was increased. The optimum dose ratio of bamboo charcoal to chitosan was 6:4, and the optimum amount was 15 mg/L; equilibrium time was 6 hr. The adsorption isotherm was non-linear and could be simulated by the Freundlich model (R2 = 0.9337). Adsorption efficiency was strongly affected by pH and natural organic matter (NOM). Removal efficiency was 16% higher at pH 3 than at pH 9. Efficiency rate was reduced by 15% with 25 mg/L NOM (UV254 = 0.089 cm(-1)) in drinking water. This study demonstrated that the bamboo charcoal modified with chitosan can effectively remove microcystin-LR from drinking water.

  10. Predicting online ratings based on the opinion spreading process

    Science.gov (United States)

    He, Xing-Sheng; Zhou, Ming-Yang; Zhuo, Zhao; Fu, Zhong-Qian; Liu, Jian-Guo

    2015-10-01

    Predicting users' online ratings is always a challenge issue and has drawn lots of attention. In this paper, we present a rating prediction method by combining the user opinion spreading process with the collaborative filtering algorithm, where user similarity is defined by measuring the amount of opinion a user transfers to another based on the primitive user-item rating matrix. The proposed method could produce a more precise rating prediction for each unrated user-item pair. In addition, we introduce a tunable parameter λ to regulate the preferential diffusion relevant to the degree of both opinion sender and receiver. The numerical results for Movielens and Netflix data sets show that this algorithm has a better accuracy than the standard user-based collaborative filtering algorithm using Cosine and Pearson correlation without increasing computational complexity. By tuning λ, our method could further boost the prediction accuracy when using Mean Absolute Error (MAE) and Root Mean Squared Error (RMSE) as measurements. In the optimal cases, on Movielens and Netflix data sets, the corresponding algorithmic accuracy (MAE and RMSE) are improved 11.26% and 8.84%, 13.49% and 10.52% compared to the item average method, respectively.

  11. Good production rate forecast based on flow, reservoir analysis

    Energy Technology Data Exchange (ETDEWEB)

    El-Feky, S.A.

    1987-03-16

    Well bore flow efficiencies under expected modes of production operations, coupled with a detailed reservoir description, are necessary for an accurate evaluation of production rate forecast. A production rate forecast for an offshore water-drive oil reservoir in the Gulf of Suez has been prepared. The best overall completion that exhibits both the highest initial producing rates and the long term producing efficiencies was determined for different wells. Three different flow configurations were examined. The wells were classified according to their productivity indices into Group I, Group II, and Group III, having average productivity indices of 53, 18 and 6 b/d/psi, respectively. The study was based on the performance of the three well groups. The Orkiszewski correlation for vertical multiphase pressure gradient calculation program available from Garrett Computing Systems was used to calculate bottom hole flowing pressures at a wide range of oil and water production rates with and without gas lift. Analysis of the expected reservoir performance was essential in evaluating the production forecast. Based on the results of the evaluation, reservoir operations, including well completions, control of water production, and gas lift requirements, have been recommended.

  12. Performance based regulation: a strategy to increase breastfeeding rates

    Directory of Open Access Journals (Sweden)

    Fernanda Cobo-Armijo

    2017-05-01

    Full Text Available The decreasing breastfeeding rate in México is of public health concern. In this paper we discus an innovative regulatory ap­proach -Performance Based Regulation- and its application to improve breastfeeding rates. This approach, forces industry to take responsibility for the lack of breastfeeding and its consequences. Failure to comply with this targets results in financial penalties. Applying performance based regulation as a strategy to improve breastfeeding is feasible because: the breastmilk substitutes market is an oligopoly, hence it is easy to identify the contribution of each market participant; the regulation’s target population is clearly defined; it has a clear regulatory standard which can be easily evaluated, and sanctions to infringement can be defined under objective parameters. Recommendations: modify public policy, celebrate concertation agreements with the industry, create persuasive sanctions, strengthen enforcement activities and coordinate every action with the International Code of Marketing of Breast-milk Substitutes.

  13. Heart rate measurement based on face video sequence

    Science.gov (United States)

    Xu, Fang; Zhou, Qin-Wu; Wu, Peng; Chen, Xing; Yang, Xiaofeng; Yan, Hong-jian

    2015-03-01

    This paper proposes a new non-contact heart rate measurement method based on photoplethysmography (PPG) theory. With this method we can measure heart rate remotely with a camera and ambient light. We collected video sequences of subjects, and detected remote PPG signals through video sequences. Remote PPG signals were analyzed with two methods, Blind Source Separation Technology (BSST) and Cross Spectral Power Technology (CSPT). BSST is a commonly used method, and CSPT is used for the first time in the study of remote PPG signals in this paper. Both of the methods can acquire heart rate, but compared with BSST, CSPT has clearer physical meaning, and the computational complexity of CSPT is lower than that of BSST. Our work shows that heart rates detected by CSPT method have good consistency with the heart rates measured by a finger clip oximeter. With good accuracy and low computational complexity, the CSPT method has a good prospect for the application in the field of home medical devices and mobile health devices.

  14. MarDRe: efficient MapReduce-based removal of duplicate DNA reads in the cloud.

    Science.gov (United States)

    Expósito, Roberto R; Veiga, Jorge; González-Domínguez, Jorge; Touriño, Juan

    2017-09-01

    This article presents MarDRe, a de novo cloud-ready duplicate and near-duplicate removal tool that can process single- and paired-end reads from FASTQ/FASTA datasets. MarDRe takes advantage of the widely adopted MapReduce programming model to fully exploit Big Data technologies on cloud-based infrastructures. Written in Java to maximize cross-platform compatibility, MarDRe is built upon the open-source Apache Hadoop project, the most popular distributed computing framework for scalable Big Data processing. On a 16-node cluster deployed on the Amazon EC2 cloud platform, MarDRe is up to 8.52 times faster than a representative state-of-the-art tool. Source code in Java and Hadoop as well as a user's guide are freely available under the GNU GPLv3 license at http://mardre.des.udc.es . rreye@udc.es.

  15. Strategies based on silica monoliths for removing pollutants from wastewater effluents: a review.

    Science.gov (United States)

    Rodrigues, Dina; Rocha-Santos, Teresa A P; Freitas, Ana C; Gomes, Ana M P; Duarte, Armando C

    2013-09-01

    Silica monoliths have been used for more than half a century in a wide variety of applications, such as stationary phases for microextraction fibers, capillary columns for chromatography, in the encapsulation of biomolecules for affinity chromatography and for microfluidic or microarray chips and, more recently, and less well known for wastewater treatment. The main objective of this review article is to specifically overview the strategies that use silica monoliths for the removal of chemical pollutants from wastewater effluents or prepared solutions. The discussion of advantages and drawbacks of such strategies will be supported with the main studies carried out so far which have been performed in laboratory environment only. The application and potential research interest in several strategies using composites and biocomposites based silica monoliths as cleaning systems are also discussed. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Space debris removal by ground-based lasers: main conclusions of the European project CLEANSPACE.

    Science.gov (United States)

    Esmiller, Bruno; Jacquelard, Christophe; Eckel, Hans-Albert; Wnuk, Edwin

    2014-11-01

    Studies show that the number of debris in low Earth orbit is exponentially growing despite future debris release mitigation measures considered. Specifically, the already existing population of small and medium debris (between 1 cm and several dozens of cm) is today a concrete threat to operational satellites. A ground-based laser solution which can remove, at low expense and in a nondestructive way, hazardous debris around selected space assets appears as a highly promising answer. This solution is studied within the framework of the CLEANSPACE project which is part of the FP7 space program. The overall CLEANSPACE objective is: to propose an efficient and affordable global system architecture, to tackle safety regulation aspects, political implications and future collaborations, to develop affordable technological bricks, and to establish a roadmap for the development and the future implantation of a fully functional laser protection system. This paper will present the main conclusions of the CLEANSPACE project.

  17. Photocatalytic Removal of Microcystin-LR by Advanced WO3-Based Nanoparticles under Simulated Solar Light

    Directory of Open Access Journals (Sweden)

    Chao Zhao

    2015-01-01

    Full Text Available A series of advanced WO3-based photocatalysts including CuO/WO3, Pd/WO3, and Pt/WO3 were synthesized for the photocatalytic removal of microcystin-LR (MC-LR under simulated solar light. In the present study, Pt/WO3 exhibited the best performance for the photocatalytic degradation of MC-LR. The MC-LR degradation can be described by pseudo-first-order kinetic model. Chloride ion (Cl− with proper concentration could enhance the MC-LR degradation. The presence of metal cations (Cu2+ and Fe3+ improved the photocatalytic degradation of MC-LR. This study suggests that Pt/WO3 photocatalytic oxidation under solar light is a promising option for the purification of water containing MC-LR.

  18. Photocatalytic Removal of Microcystin-LR by Advanced WO3-Based Nanoparticles under Simulated Solar Light

    Science.gov (United States)

    Zhao, Chao; Li, Dawei; Feng, Chuanping; Zhang, Zhenya; Sugiura, Norio; Yang, Yingnan

    2015-01-01

    A series of advanced WO3-based photocatalysts including CuO/WO3, Pd/WO3, and Pt/WO3 were synthesized for the photocatalytic removal of microcystin-LR (MC-LR) under simulated solar light. In the present study, Pt/WO3 exhibited the best performance for the photocatalytic degradation of MC-LR. The MC-LR degradation can be described by pseudo-first-order kinetic model. Chloride ion (Cl−) with proper concentration could enhance the MC-LR degradation. The presence of metal cations (Cu2+ and Fe3+) improved the photocatalytic degradation of MC-LR. This study suggests that Pt/WO3 photocatalytic oxidation under solar light is a promising option for the purification of water containing MC-LR. PMID:25884038

  19. Space debris removal using a high-power ground-based laser

    Energy Technology Data Exchange (ETDEWEB)

    Monroe, D.K.

    1993-08-01

    The feasibility of utilizing a ground-based laser without an orbital mirror for space debris removal is examined. Technical issues include atmospheric transmission losses, adaptive-optics corrections of wavefront distortions, laser field of view limitations, and laser-induced impulse generation. The physical constraints require a laser with megawatt output, long run-time capability, and wavelength with good atmospheric transmission characteristics. It is found that a 5-MW reactor-pumped laser can deorbit debris having masses of the order of one kilogram from orbital altitudes to be used by Space Station Freedom. Debris under one kilogram can be deorbited after one pass over the laser site, while larger debris can be deorbited or transferred to alternate orbits after multiple passes over the site.

  20. Removal of metal cations from wastewater using recycled wool-based non-woven material

    Directory of Open Access Journals (Sweden)

    MAJA RADETIC

    2007-06-01

    Full Text Available In this study, the effect of low-temperature air plasma, biopolymer chitosan and hydrogen peroxide treatment of recycled wool-based non-woven material on metal cation uptake was investigated. Recycled wool-based material either as an untreated or modified material showed ability to bind all investigated metal cations in the following order: Pb2+>Cu2+>Zn2+>Co2+. Material performed good selectivity due to distinct sorption rates of studied metal cations.

  1. Chitosan-based hydrogel for dye removal from aqueous solutions: Optimization of the preparation procedure

    Science.gov (United States)

    Gioiella, Lucia; Altobelli, Rosaria; de Luna, Martina Salzano; Filippone, Giovanni

    2016-05-01

    The efficacy of chitosan-based hydrogels in the removal of dyes from aqueous solutions has been investigated as a function of different parameters. Hydrogels were obtained by gelation of chitosan with a non-toxic gelling agent based on an aqueous basic solution. The preparation procedure has been optimized in terms of chitosan concentration in the starting solution, gelling agent concentration and chitosan-to-gelling agent ratio. The goal is to properly select the material- and process-related parameters in order to optimize the performances of the chitosan-based dye adsorbent. First, the influence of such factors on the gelling process has been studied from a kinetic point of view. Then, the effects on the adsorption capacity and kinetics of the chitosan hydrogels obtained in different conditions have been investigated. A common food dye (Indigo Carmine) has been used for this purpose. Noticeably, although the disk-shaped hydrogels are in the bulk form, their adsorption capacity is comparable to that reported in the literature for films and beads. In addition, the bulk samples can be easily separated from the liquid phase after the adsorption process, which is highly attractive from a practical point of view. Compression tests reveal that the samples do not breakup even after relatively large compressive strains. The obtained results suggest that the fine tuning of the process parameters allows the production of mechanical resistant and highly adsorbing chitosan-based hydrogels.

  2. Investigating the effect of gas flow rate, inlet ozone concentration and relative humidity on the efficacy of catalytic ozonation process in the removal of xylene from waste airstream

    Directory of Open Access Journals (Sweden)

    H.R. MokaramI

    2010-10-01

    Full Text Available Background and aimsThe catalytic ozonation is an efficient process for the degradation of volatile organic compounds from contaminated air stream. This study was aimed at investigating the efficacy of catalytic ozonation process in removal of xylene from the polluted air stream andthe influence of retention time (gas flow rate, inlet ozone dose and relative humidity on this performanceMethodsthe catalytic ozonation of xylene was conducted using a bench scale set-up consisted of a syringe pump,an air pump, an ozone generator, and a glass reactor packed with activated carbon. Several experimental run was defined to investigate the influence of the selectedoperational variables.ResultsThe results indicated that the efficiency of catalytic ozonation was greater than that of single adsorption in removal of xylene under similar inlet concentration and relative humidity. We found a significant catalytic effect for activated carbon when used in combination with ozonation process, leading to improvement of xylene removal percentage. In addition, the elimination capacity of the system improved with the increase of inlet ozone dose as well as gas flow rate. The relative humidity showed a positive effect of the xylene removal at the range of 5 to 50%, while the higher humidity (more than 50% resulted in reduction of the performance.ConclusionThe findings of the present work revealed that the catalytic ozonation process can be an efficient technique for treating the air streams containing industrial concentrations of xylene. Furthermore, there is a practical potential to retrofit the present adsorption systems intothe catalytic ozonation simply by coupling them with the ozonation system. the catalytic ozonation of xylene was conducted using a bench scale set-up consisted of a syringe pump,an air pump, an ozone generator, and a glass reactor packed with activated carbon. Several experimental run was defined to investigate the influence of the selected

  3. Evaluation of radon adsorption characteristics of a coconut shell-based activated charcoal system for radon and thoron removal applications.

    Science.gov (United States)

    Karunakara, N; Sudeep Kumara, K; Yashodhara, I; Sahoo, B K; Gaware, J J; Sapra, B K; Mayya, Y S

    2015-04-01

    Radon ((222)Rn), thoron ((220)Rn), and their decay products contribute a major fraction (more than 50%) of doses received from ionisation radiation in public domain indoor environments and occupation environments such as uranium mines, thorium plants, and underground facilities, and are recognised as important radiological hazardous materials, which need to be controlled. This paper presents studies on the removal of (222)Rn and (220)Rn from air using coconut shell-based granular activated charcoal cylindrical adsorber beds. Experiments were conducted to evaluate the (222)Rn and (220)Rn adsorption characteristics, and the mitigation efficiency of coconut-based activated charcoal available in India. The performance parameters evaluated include breakthrough time (τ) and adsorption coefficient (K), and degassing characteristics of the charcoal bed of varying dimensions at different flow rates. While the breakthrough for (222)Rn occurred depending on the dimension of the adsorber bed and flow rates, for (220)Rn, the breakthrough did not occur. The breakthrough curve exhibited a stretched S-shape response, instead of the theoretically predicted sharp step function. The experiments confirm that the breakthrough time individually satisfies the quadratic relationship with respect to the diameter of the bed, and the linear relationship with respect to the length, as predicted in the theory. The K value varied in the range of 2.3-4.12 m(3) kg(-1) with a mean value of 2.99 m(3) kg(-1). The K value was found to increase with the increase in flow rate. Heating the charcoal to ∼ 100 °C resulted in degassing of the adsorbed (222)Rn, and the K of the degassed charcoal and virgin charcoal were found to be similar with no deterioration in performance indicating the re-usability of the charcoal. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. A rate-based transcutaneous CO2 sensor for noninvasive respiration monitoring.

    Science.gov (United States)

    Chatterjee, M; Ge, X; Kostov, Y; Luu, P; Tolosa, L; Woo, H; Viscardi, R; Falk, S; Potts, R; Rao, G

    2015-05-01

    The pain and risk of infection associated with invasive blood sampling for blood gas measurements necessitate the search for reliable noninvasive techniques. In this work we developed a novel rate-based noninvasive method for a safe and fast assessment of respiratory status. A small sampler was built to collect the gases diffusing out of the skin. It was connected to a CO2 sensor through gas-impermeable tubing. During a measurement, the CO2 initially present in the sampler was first removed by purging it with nitrogen. The gases in the system were then recirculated between the sampler and the CO2 sensor, and the CO2 diffusion rate into the sampler was measured. Because the measurement is based on the initial transcutaneous diffusion rate, reaching mass transfer equilibrium and heating the skin is no longer required, thus, making it much faster and safer than traditional method. A series of designed experiments were performed to analyze the effect of the measurement parameters such as sampler size, measurement location, subject positions, and movement. After the factor analysis tests, the prototype was sent to a level IV NICU for clinical trial. The results show that the measured initial rate of increase in CO2 partial pressure is linearly correlated with the corresponding arterial blood gas measurements. The new approach can be used as a trending tool, making frequent blood sampling unnecessary for respiratory status monitoring.

  5. Fuzzy MADM Approach for Rating of Process-Based Fraud

    Directory of Open Access Journals (Sweden)

    Solichul Huda

    2016-02-01

    Full Text Available Process-Based Fraud (PBF is fraud enabled by process deviations that occur in business processes. Several studies have proposed PBF detection methods; however, false decisions are still often made because of cases with low deviation. Low deviation is caused by ambiguity in determining fraud attribute values and low frequency of occurrence. This paper proposes a method of detecting PBF with low deviation in order to correctly detect fraudulent cases. Firstly, the fraudulence attributes are established, then a fuzzy approach is utilized to weigh the importance of the fraud attributes. Further, multi-attribute decision making (MADM is employed to obtain a PBF rating according to attribute values and attribute importance weights. Finally, a decision is made whether the deviation is fraudulent or not, based on the PBF rating. Experimental validation showed that the accuracy and false discovery rate of the method were 0.92 and 0.33, respectively.

  6. Flexible thermoplastic denture base materials for aesthetical removable partial denture framework.

    Science.gov (United States)

    Singh, Kunwarjeet; Aeran, Himanshu; Kumar, Narender; Gupta, Nidhi

    2013-10-01

    Conventional fixed partial dentures, implant supported Fixed Partial Dentures (FDPs) and removable partial dentures are the most common treatment modalities for the aesthetic and functional rehabilitation of partially edentulous patients. Although implants and FDP have certain advantages over removable partial dentures, in some cases, removable partial dentures may be the only choice which is available. Removable cast partial dentures are used as definitive removable prostheses when indicated, but location of clasps may affect aesthetics. So, when patient is concerned about aesthetics, flexible partial dentures which is aesthetically superior to flipper and cast partial dentures, may be considered. But for the success of flexible removable partial denture, proper diagnosis, treatment planning and insertion technique of this prosthesis is very important, which have been thoroughly described in this article.

  7. Late Complications and Stone Recurrence Rates after Bile Duct Stone Removal by Endoscopic Sphincterotomy and Large Balloon Dilation are Similar to Those after Endoscopic Sphincterotomy Alone

    Science.gov (United States)

    Kim, Ka Young; Kim, Ho Gak; Kim, Byeong Suk; Jung, Jin Tae; Kwon, Joong Goo; Kim, Eun Young; Lee, Chang Hyeong

    2013-01-01

    Background/Aims Between endoscopic sphincterotomy (ES) alone and combined endoscopic sphincterotomy and large balloon dilation (ES-LBD) groups, efficacy and long-term complications, difference in biliary stone recurrence rate, and risk factors of stone recurrence were compared. Methods Medical records of 222 patients who underwent ERCP for biliary stone removal were retrospectively reviewed. Patients with dilated CBD ≥11 mm and follow-up longer than 6 months were included. Results There were 101 patients in ES-LBD group and 121 patients in ES group. Mean follow-up duration was 25.0 (6-48) months and 13.0 (6-43) months, respectively (p=0.001). There was no difference in number of ERCP sessions, brown pigment stones, angle between mid and distal common bile duct (CBD angle) <135°, and lithotripsy rate. Complete retrieval success rate was excellent in both groups (100% vs. 99%). Early complication rate of ES-LBD and ES alone group was 4 and 4.1%, respectively (p=1.000). One patient in ES-LBD group died from delayed bleeding. Late complication rate was 5.9 and 3.3%, respectively (p=1.000). Stone recurrence rate was 6.9% and 5.8%, respectively (p=0.984). The only Independent risk factor of stone recurrence was presence of periampullary diverticulum. Conclusions Late complication and stone recurrence rates were similar between ES-LBD and ES alone groups. PMID:24340257

  8. Doppler-Based Flow Rate Sensing in Microfluidic Channels

    Directory of Open Access Journals (Sweden)

    Liron Stern

    2014-09-01

    Full Text Available We design, fabricate and experimentally demonstrate a novel generic method to detect flow rates and precise changes of flow velocity in microfluidic devices. Using our method we can measure flow rates of ~2 mm/s with a resolution of 0.08 mm/s. The operation principle is based on the Doppler shifting of light diffracted from a self-generated periodic array of bubbles within the channel and using self-heterodyne detection to analyze the diffracted light. As such, the device is appealing for variety of “lab on chip” bio-applications where a simple and accurate speed measurement is needed, e.g., for flow-cytometry and cell sorting.

  9. COD removal characteristics in air-cathode microbial fuel cells

    KAUST Repository

    Zhang, Xiaoyuan

    2015-01-01

    © 2014 Elsevier Ltd. Exoelectrogenic microorganisms in microbial fuel cells (MFCs) compete with other microorganisms for substrate. In order to understand how this affects removal rates, current generation, and coulombic efficiencies (CEs), substrate removal rates were compared in MFCs fed a single, readily biodegradable compound (acetate) or domestic wastewater (WW). Removal rates based on initial test conditions fit first-order kinetics, but rate constants varied with circuit resistance. With filtered WW (100Ω), the rate constant was 0.18h- 1, which was higher than acetate or filtered WW with an open circuit (0.10h- 1), but CEs were much lower (15-24%) than acetate. With raw WW (100Ω), COD removal proceeded in two stages: a fast removal stage with high current production, followed by a slower removal with little current. While using MFCs increased COD removal rate due to current generation, secondary processes will be needed to reduce COD to levels suitable for discharge.

  10. 76 FR 26549 - Removal of Certain References to Credit Ratings Under the Securities Exchange Act of 1934

    Science.gov (United States)

    2011-05-06

    ...); and Asset class-specific factors (e.g., in the case of structured finance products, the quality of the.... of Finance 1431, 1433, n.5 (1994) (noting that ``issuers with the lowest ratings find that they... derivatives-related credit risk. \\39\\ As a condition of approval, applicants must maintain an ``early warning...

  11. Removal of inorganic mercury and methylmercury from surface waters following coagulation of dissolved organic matter with metal-based salts.

    Science.gov (United States)

    Henneberry, Yumiko K; Kraus, Tamara E C; Fleck, Jacob A; Krabbenhoft, David P; Bachand, Philip M; Horwath, William R

    2011-01-01

    The presence of inorganic mercury (IHg) and methylmercury (MeHg) in surface waters is a health concern worldwide. This study assessed the removal potential use of metal-based coagulants as a means to remove both dissolved IHg and MeHg from natural waters and provides information regarding the importance of Hg associations with the dissolved organic matter (DOM) fraction and metal hydroxides. Previous research indicated coagulants were not effective at removing Hg from solution; however these studies used high concentrations of Hg and did not reflect naturally occurring concentrations of Hg. In this study, water collected from an agricultural drain in the Sacramento-San Joaquin Delta was filtered to isolate the dissolved organic matter (DOM) fraction. The DOM was then treated with a range of coagulant doses to determine the efficacy of removing all forms of Hg from solution. Three industrial-grade coagulants were tested: ferric chloride, ferric sulfate, and polyaluminum chloride. Coagulation removed up to 85% of DOM from solution. In the absence of DOM, all three coagulants released IHg into solution, however in the presence of DOM the coagulants removed up to 97% of IHg and 80% of MeHg. Results suggest that the removal of Hg is mediated by DOM-coagulant interactions. There was a preferential association of IHg with the more aromatic, higher molecular weight fraction of DOM but no such relationship was found for MeHg. This study offers new fundamental insights regarding large-scale removal of Hg at environmentally relevant regarding large-scale removal of Hg at environmentally relevant concentrations. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Infrared imaging based hyperventilation monitoring through respiration rate estimation

    Science.gov (United States)

    Basu, Anushree; Routray, Aurobinda; Mukherjee, Rashmi; Shit, Suprosanna

    2016-07-01

    A change in the skin temperature is used as an indicator of physical illness which can be detected through infrared thermography. Thermograms or thermal images can be used as an effective diagnostic tool for monitoring and diagnosis of various diseases. This paper describes an infrared thermography based approach for detecting hyperventilation caused due to stress and anxiety in human beings by computing their respiration rates. The work employs computer vision techniques for tracking the region of interest from thermal video to compute the breath rate. Experiments have been performed on 30 subjects. Corner feature extraction using Minimum Eigenvalue (Shi-Tomasi) algorithm and registration using Kanade Lucas-Tomasi algorithm has been used here. Thermal signature around the extracted region is detected and subsequently filtered through a band pass filter to compute the respiration profile of an individual. If the respiration profile shows unusual pattern and exceeds the threshold we conclude that the person is stressed and tending to hyperventilate. Results obtained are compared with standard contact based methods which have shown significant correlations. It is envisaged that the thermal image based approach not only will help in detecting hyperventilation but can assist in regular stress monitoring as it is non-invasive method.

  13. Effects of operation parameters on nutrient removal from wastewater and high-protein biomass production in a duckweed-based (Lemma aequinoctialis) pilot-scale system.

    Science.gov (United States)

    Zhao, Yonggui; Fang, Yang; Jin, Yanling; Huang, Jun; Bao, Shu; He, Zhiming; Wang, Feng; Zhao, Hai

    2014-01-01

    The effects of water depth, coverage rate and harvest regime on nutrient removal from wastewater and high-protein biomass production were assessed in a duckweed-based (Lemna aequinoctialis) pilot-scale wastewater treatment system (10 basins × 12 m(2)) that is located near Dianchi Lake in China. The results indicated that a water depth of 50 cm, a coverage rate of 150% and a harvest regime of 4 days were preferable conditions, under which excellent records of high-protein duckweed (dry matter production of 6.65 g/m(2)/d with crude protein content of 36.16% and phosphorus content of 1.46%) were obtained at a temperature of 12-21 °C. At the same time, the system achieved a removal efficiency of 66.16, 23.1, 48.3 and 76.52% for NH4(+)-N, TN, TP and turbidity, respectively, with the considerable removal rate of 0.465 g/m(2)/d for TN and 0.134 g/m(2)/d for TP at a hydraulic retention time of 6 days. In additionally, it was found that a lower duckweed density could lead to higher dissolved oxygen in the water and then a higher removal percentage of NH4(+)-N by nitrobacteria. This study obtains the preferable operation conditions for wastewater treatment and high-protein biomass production in a duckweed-based pilot-scale system, supplying an important reference for further large-scale applications of duckweed.

  14. High Data Rate Optical Wireless Communications Based on Ultraviolet Band

    KAUST Repository

    Sun, Xiaobin

    2017-10-01

    Optical wireless communication systems based on ultraviolet (UV)-band has a lot inherent advantages, such as low background solar radiation, low device dark noise. Besides, it also has small restrictive requirements for PAT (pointing, acquisition, and tracking) because of its high atmospheric scattering with molecules and aerosols. And these advantages are driving people to explore and utilize UV band for constructing and implementing a high-data-rate, less PAT communication links, such as diffuse-line-of-sight links (diffuse-LOS) and non-line-of-sight (NLOS). The responsivity of the photodetector at UV range is far lower than that of visible range, high power UV transmitters which can be easily modulated are under investigation. These factors make it is hard to realize a high-data-rate diffuse-LOS or NLOS UV communication links. To achieve a UV link mentioned above with current devices and modulation schemes, this thesis presents some efficient modulation schemes and available devices for the time being. Besides, a demonstration of ultraviolet-B (UVB) communication link is implemented utilizing quadrature amplitude modulation (QAM) orthogonal frequency-division multiplexing (OFDM). The demonstration is based on a 294-nm UVB-light-emitting-diode (UVB-LED) with a full-width at half-maximum (FWHM) of 9 nm, and according to the measured L-I-V curve, we set the bias voltage as 7V for maximum the ac amplitude and thus get a high signal-noise-ratio (SNR) channel, and the light output power is 190 μW with such bias voltage. Besides, there is a unique silica gel lens on top of the LED to concentrate the beam. A -3-dB bandwidth of 29 MHz was measured and a high-speed near-solar-blind communication link with a data rate of 71 Mbit/s was achieved using 8-QAM-OFDM at perfect alignment, and 23.6 Mbit/s using 2-QAM-OFDM when the angle subtended by the pointing direction of the UVB-LED and photodetector (PD) is 12 degrees, thus establishing a diffuse-line-of-sight (LOS) link

  15. [Design of Oxygen Saturation, Heart Rate, Respiration Rate Detection System Based on Smartphone of Android Operating System].

    Science.gov (United States)

    Zhu, Mingshan; Zeng, Bixin

    2015-03-01

    In this paper, we designed an oxygen saturation, heart rate, respiration rate monitoring system based on smartphone of android operating system, physiological signal acquired by MSP430 microcontroller and transmitted by Bluetooth module.

  16. Comprehensive evaluation of nitrogen removal rate and biomass, ethanol, and methane production yields by combination of four major duckweeds and three types of wastewater effluent.

    Science.gov (United States)

    Toyama, Tadashi; Hanaoka, Tsubasa; Tanaka, Yasuhiro; Morikawa, Masaaki; Mori, Kazuhiro

    2017-11-24

    To assess the potential of duckweeds as agents for nitrogen removal and biofuel feedstocks, Spirodela polyrhiza, Lemna minor, Lemna gibba, and Landoltia punctata were cultured in effluents of municipal wastewater, swine wastewater, or anaerobic digestion for 4 days. Total dissolved inorganic nitrogen (T-DIN) of 20-50 mg/L in effluents was effectively removed by inoculating with 0.3-1.0 g/L duckweeds. S. polyrhiza showed the highest nitrogen removal (2.0-10.8 mg T-DIN/L/day) and biomass production (52.6-70.3 mg d.w./L/day) rates in all the three effluents. Ethanol and methane were produced from duckweed biomass grown in each effluent. S. polyrhiza and L. punctata biomass showed higher ethanol (0.168-0.191, 0.166-0.172 and 0.174-0.191 g-ethanol/g-biomass, respectively) and methane (340-413 and 343-408 NL CH 4 /kg VS, respectively) production potentials than the others, which is related to their higher carbon and starch contents and calorific values. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  17. Cognition and behavior in the fallacy of base rates

    Directory of Open Access Journals (Sweden)

    Claudia Milena Pico Bonilla

    2017-05-01

    Full Text Available Behavioral economics has applied psychology concepts related to cognitive analysis, which gives little importance to environmental effects. In contrast, the analysis of behavior gives a central role to the environment, and therefore employs concepts such as reinforcement schedules and stimuli control. In this document presents the cognitive-behavioral discussion about choice behavior. In addition, we compare their methods through two experiments dealing with the base-rate fallacy. In the experiments, the characteristics of the stimuli (verbal and non-verbal are varied and contrasted. The paper concludes that this fallacy occurs on a smaller scale when there are less irrelevant stimuli.

  18. Drilling load modeling and validation based on the filling rate of auger flute in planetary sampling

    Directory of Open Access Journals (Sweden)

    Qiquan Quan

    2017-02-01

    Full Text Available Some type of penetration into a subsurface is required in planetary sampling. Drilling and coring, due to its efficient penetrating and cuttings removal characteristics, has been widely applied in previous sampling missions. Given the complicated mechanical properties of a planetary regolith, suitable drilling parameters should be matched with different drilling formations properly. Otherwise, drilling faults caused by overloads could easily happen. Hence, it is necessary to establish a drilling load model, which is able to reveal the relationships among drilling loads, an auger’s structural parameters, soil’s mechanical properties, and relevant drilling parameters. A concept for the filling rate of auger flute (FRAF is proposed to describe drilling conditions. If the FRAF index under one group of drilling parameters is less than 1, this means that the auger flute currently removes cuttings smoothly. Otherwise, the auger will be choked with compressed cuttings. In drilling operations, the drilling loads on the auger mainly come from the conveyance action, while the drilling loads on the drill bit primarily come from the cutting action. Experiments in one typical lunar regolith simulant indicate that the estimated drilling loads based on the FRAF coincide with the test results quite well. Based on this drilling load model, drilling parameters have been optimized.

  19. Decision-Based Marginal Total Variation Diffusion for Impulsive Noise Removal in Color Images

    Directory of Open Access Journals (Sweden)

    Hongyao Deng

    2017-01-01

    Full Text Available Impulsive noise removal for color images usually employs vector median filter, switching median filter, the total variation L1 method, and variants. These approaches, however, often introduce excessive smoothing and can result in extensive visual feature blurring and thus are suitable only for images with low density noise. A marginal method to reduce impulsive noise is proposed in this paper that overcomes this limitation that is based on the following facts: (i each channel in a color image is contaminated independently, and contaminative components are independent and identically distributed; (ii in a natural image the gradients of different components of a pixel are similar to one another. This method divides components into different categories based on different noise characteristics. If an image is corrupted by salt-and-pepper noise, the components are divided into the corrupted and the noise-free components; if the image is corrupted by random-valued impulses, the components are divided into the corrupted, noise-free, and the possibly corrupted components. Components falling into different categories are processed differently. If a component is corrupted, modified total variation diffusion is applied; if it is possibly corrupted, scaled total variation diffusion is applied; otherwise, the component is left unchanged. Simulation results demonstrate its effectiveness.

  20. Zirconium-Based Metal–Organic Framework for Removal of Perrhenate from Water

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Debasis; Xu, Wenqian; Nie, Zimin; Johnson, Lewis E. V.; Coghlan, Campbell; Sushko, Maria L.; Kim, Dongsang; Schweiger, Michael J.; Kruger, Albert A.; Doonan, Christian J.; Thallapally, Praveen K.

    2016-09-06

    Efficient removal of pertechnetate (TcO4 -) anions from liquid waste or melter off-gas solution for alternative treatment is one of the promising options to manage 99Tc in legacy nuclear waste. Safe immobilization of 99Tc is of major importance due to its long half-life (t1/2= 2.13 × 105 yrs) and environmental mobility. Different types of inorganic and solid state ion-exchange materials such as layered double hydroxides have been shown to absorb TcO4 - anions from water. However, both high capacity and selectivity have yet to be achieved in a single material. Herein, we show that a protonated version of an ultra-stable zirconium based metalorganic framework can adsorb perrhenate (ReO4 -) anions, a non-radioactive surrogate for TcO4 -, from water even in the presence of other common anions. Synchrotron based powder X-ray diffraction and molecular simulations were used to identify the position of the adsorbed ReO4 - (surrogate for TcO4 -) molecule within the framework.

  1. Zirconium-Based Metal-Organic Framework for Removal of Perrhenate from Water.

    Science.gov (United States)

    Banerjee, Debasis; Xu, Wenqian; Nie, Zimin; Johnson, Lewis E V; Coghlan, Campbell; Sushko, Maria L; Kim, Dongsang; Schweiger, Michael J; Kruger, Albert A; Doonan, Christian J; Thallapally, Praveen K

    2016-09-06

    The efficient removal of pertechnetate (TcO4(-)) anions from liquid waste or melter off-gas solution for an alternative treatment is one of the promising options to manage (99)Tc in legacy nuclear waste. Safe immobilization of (99)Tc is of major importance because of its long half-life (t1/2 = 2.13 × 10(5) yrs) and environmental mobility. Different types of inorganic and solid-state ion-exchange materials have been shown to absorb TcO4(-) anions from water. However, both high capacity and selectivity have yet to be achieved in a single material. Herein, we show that a protonated version of an ultrastable zirconium-based metal-organic framework can adsorb perrhenate (ReO4(-)) anions, a nonradioactive surrogate for TcO4(-), from water even in the presence of other common anions. Synchrotron-based powder X-ray diffraction and molecular simulations were used to identify the position of the adsorbed ReO4(-) (surrogate for TcO4(-)) molecule within the framework.

  2. Zirconium-Based Metal–Organic Framework for Removal of Perrhenate from Water

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Debasis; Xu, Wenqian; Nie, Zimin; Johnson, Lewis E. V.; Coghlan, Campbell; Sushko, Maria L.; Kim, Dongsang; Schweiger, Michael J.; Kruger, Albert A.; Doonan, Christian J.; Thallapally, Praveen K.

    2016-09-06

    Efficient removal of pertechnetate (TcO4-) anions from liquid waste or melter off-gas solution for alternative treatment is one of the promising options to manage 99Tc in legacy nuclear waste. Safe immobilization of 99Tc is of major importance due to its long half-life (t1/2= 2.13 × 105 yrs) and environmental mobility. Different types of inorganic and solid state ion-exchange materials such as layered double hydroxides have been shown to absorb TcO4- anions from water. However, both high capacity and selectivity have yet to be achieved in a single material. Herein, we show that a protonated version of an ultra-stable zirconium based metal-organic framework can adsorb perrhenate (ReO4-) anions, a non-radioactive sur-rogate for TcO4-, from water even in the presence of other common anions. Synchrotron based powder X-ray diffraction and molecular simulations were used to identify the position of the adsorbed ReO4- (surrogate for TcO4-) molecule within the framework.

  3. Removal of anti-Stokes emission background in STED microscopy by FPGA-based synchronous detection.

    Science.gov (United States)

    Castello, M; Tortarolo, G; Coto Hernández, I; Deguchi, T; Diaspro, A; Vicidomini, G

    2017-05-01

    In stimulated emission depletion (STED) microscopy, the role of the STED beam is to de-excite, via stimulated emission, the fluorophores that have been previously excited by the excitation beam. This condition, together with specific beam intensity distributions, allows obtaining true sub-diffraction spatial resolution images. However, if the STED beam has a non-negligible probability to excite the fluorophores, a strong fluorescent background signal (anti-Stokes emission) reduces the effective resolution. For STED scanning microscopy, different synchronous detection methods have been proposed to remove this anti-Stokes emission background and recover the resolution. However, every method works only for a specific STED microscopy implementation. Here we present a user-friendly synchronous detection method compatible with any STED scanning microscope. It exploits a data acquisition (DAQ) card based on a field-programmable gate array (FPGA), which is progressively used in STED microscopy. In essence, the FPGA-based DAQ card synchronizes the fluorescent signal registration, the beam deflection, and the excitation beam interruption, providing a fully automatic pixel-by-pixel synchronous detection method. We validate the proposed method in both continuous wave and pulsed STED microscope systems.

  4. A systematic review of light-based home-use devices for hair removal and considerations on human safety

    DEFF Research Database (Denmark)

    Thaysen-Petersen, D; Bjerring, P; Dierickx, C

    2012-01-01

    , one CT, five UCTs) and limited evidence for laser devices (one diode laser, one UCT). Most studies evaluated short-term hair reduction up to 3 and 6 months following light exposure at different body sites. Hair reduction percentages ranged from 6% to 72% after repetitive treatments. The most......Background Hair removal with professional light-based devices is established as an effective, mainstream treatment. The field of optical home-based hair removal is evolving and movement from control by physicians into hands of consumers warrants understanding efficacy and human safety. Objectives...... To systematically review and evaluate the efficacy and human safety of currently available home-based optical hair removal devices. Methods A comprehensive Pub Med literature search was conducted which systematically identified publications of relevance. Prospective clinical trials were included whether controlled...

  5. Solid formation in piperazine rate-based simulation

    DEFF Research Database (Denmark)

    Gaspar, Jozsef; Thomsen, Kaj; von Solms, Nicolas

    2014-01-01

    . It uses the extended UNIQUAC thermodynamic model for phase equilibria and thermal properties estimation. The mass and heat transfer phenomena is implemented in a film model approach, based on second order reactions kinetics. The transfer fluxes are calculated using the concentration of the dissolved......Piperazine is a promising solvent for reducing CO2 emissions. It can be applied for the post-combustion capture process and it has limited degradation and fast kinetics. However, precipitation and slurry formation still represent a challenge for the PZ-CO2-H2O system from an operational point...... of view but also from a modeling perspective. The present work develops a rate-based model for CO2 absorption and desorption modeling for gas-liquid-solid systems and it is demonstrated for the piperazine CO2 capture process. This model is an extension of the DTU CAPCO2 model to precipitating systems...

  6. Assessing heart rate variability through wavelet-based statistical measures.

    Science.gov (United States)

    Wachowiak, Mark P; Hay, Dean C; Johnson, Michel J

    2016-10-01

    Because of its utility in the investigation and diagnosis of clinical abnormalities, heart rate variability (HRV) has been quantified with both time and frequency analysis tools. Recently, time-frequency methods, especially wavelet transforms, have been applied to HRV. In the current study, a complementary computational approach is proposed wherein continuous wavelet transforms are applied directly to ECG signals to quantify time-varying frequency changes in the lower bands. Such variations are compared for resting and lower body negative pressure (LBNP) conditions using statistical and information-theoretic measures, and compared with standard HRV metrics. The latter confirm the expected lower variability in the LBNP condition due to sympathetic nerve activity (e.g. RMSSD: p=0.023; SDSD: p=0.023; LF/HF: p=0.018). Conversely, using the standard Morlet wavelet and a new transform based on windowed complex sinusoids, wavelet analysis of the ECG within the observed range of heart rate (0.5-1.25Hz) exhibits significantly higher variability, as measured by frequency band roughness (Morlet CWT: p=0.041), entropy (Morlet CWT: p=0.001), and approximate entropy (Morlet CWT: p=0.004). Consequently, this paper proposes that, when used with well-established HRV approaches, time-frequency analysis of ECG can provide additional insights into the complex phenomenon of heart rate variability. Copyright © 2016. Published by Elsevier Ltd.

  7. Significance of Test-based Ratings for Metropolitan Boston Schools

    Directory of Open Access Journals (Sweden)

    Craig Bolon

    2001-10-01

    Full Text Available In 1998 Massachusetts began state-sponsored, annual achievement testing of all students in three public school grades. It has created a school and district rating system for which scores on these tests are the sole factor. It proposes to use tenth-grade test scores as a sole criterion for high school graduation, beginning with the class of 2003. The state is treating scores and ratings as though they were precise educational measures of high significance. A review of tenth-grade mathematics test scores from academic high schools in metropolitan Boston showed that statistically they are not. Community income is strongly correlated with test scores and accounted for more than 80 percent of the variance in average scores for a sample of Boston-area communities. Once community income was included in models, other factors--including percentages of students in disadvantaged populations, (Note 1 percentages receiving special education, percentages eligible for free or reduced price lunch, percentages with limited English proficiency, school sizes, school spending levels, and property values--all failed to associate substantial additional variance. Large uncertainties in residuals of school-averaged scores, after subtracting predictions based on community income, tend to make the scores ineffective for rating performance of schools. Large uncertainties in year-to-year score changes tend to make the score changes ineffective for measuring performance trends.

  8. Traditional waveform based spike sorting yields biased rate code estimates.

    Science.gov (United States)

    Ventura, Valérie

    2009-04-28

    Much of neuroscience has to do with relating neural activity and behavior or environment. One common measure of this relationship is the firing rates of neurons as functions of behavioral or environmental parameters, often called tuning functions and receptive fields. Firing rates are estimated from the spike trains of neurons recorded by electrodes implanted in the brain. Individual neurons' spike trains are not typically readily available, because the signal collected at an electrode is often a mixture of activities from different neurons and noise. Extracting individual neurons' spike trains from voltage signals, which is known as spike sorting, is one of the most important data analysis problems in neuroscience, because it has to be undertaken prior to any analysis of neurophysiological data in which more than one neuron is believed to be recorded on a single electrode. All current spike-sorting methods consist of clustering the characteristic spike waveforms of neurons. The sequence of first spike sorting based on waveforms, then estimating tuning functions, has long been the accepted way to proceed. Here, we argue that the covariates that modulate tuning functions also contain information about spike identities, and that if tuning information is ignored for spike sorting, the resulting tuning function estimates are biased and inconsistent, unless spikes can be classified with perfect accuracy. This means, for example, that the commonly used peristimulus time histogram is a biased estimate of the firing rate of a neuron that is not perfectly isolated. We further argue that the correct conceptual way to view the problem out is to note that spike sorting provides information about rate estimation and vice versa, so that the two relationships should be considered simultaneously rather than sequentially. Indeed we show that when spike sorting and tuning-curve estimation are performed in parallel, unbiased estimates of tuning curves can be recovered even from

  9. Model study of the enzymatic modification of natural extracts: peroxidase-based removal of eugenol from rose essential oil.

    Science.gov (United States)

    Bouhlel, Charfeddine; Dolhem, Gwenn'Ann; Fernandez, Xavier; Antoniotti, Sylvain

    2012-02-01

    A protocol based on the use of horseradish peroxidase (HRP) is proposed for the removal of allergenic eugenol from rose essential oil without loss of the organoleptic quality and with a good conservation of the chemical composition. For the first time, an enzyme-based strategy is proposed for essential oils treatment and opens new opportunities in the detoxification of natural extracts used in perfumery and cosmetics. Our results on eugenol in rose essential oil constitute a first step toward the development of efficient and mild processes for the removal of more toxic compounds of natural extracts.

  10. Biological denitrification process based on the Fe(0)-carbon micro-electrolysis for simultaneous ammonia and nitrate removal from low organic carbon water under a microaerobic condition.

    Science.gov (United States)

    Deng, Shihai; Li, Desheng; Yang, Xue; Xing, Wei; Li, Jinlong; Zhang, Qi

    2016-11-01

    A combined process between micro-electrolysis and biological denitrification (MEBD) using iron scraps and an activated carbon-based micro-electrolysis carrier was developed for nitrogen removal under a microaerobic condition. The process provided NH4(+)-N and total nitrogen (TN) removal efficiencies of 92.6% and 95.3%, respectively, and TN removal rate of 0.373±0.11kgN/(m(3)d) at corresponding DO of 1.0±0.1mg/L and HRT of 3h, and the optimal pH of 7.6-8.4. High-throughput sequencing analysis verified that dominant classes belonged to β-, α-, and γ-Proteobacteria, and Nitrospira. The dominant genera Hydrogenophaga and Sphaerotilus significantly increased during the operation, covering 13.2% and 6.1% in biofilms attached to the carrier in the middle of the reactor, respectively. Autotrophic denitrification contributed to >80% of the TN removal. The developed MEBD achieved efficient simultaneous nitrification and autotrophic denitrification, presenting significant potential for application in practical low organic carbon water treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. An empirical model for salt removal percentage in water under the effect of different current intensities of current carrying coil at different flow rates

    Directory of Open Access Journals (Sweden)

    Rameen S. AbdelHady

    2011-10-01

    Full Text Available The magnetic treatment of hard water is an alternative, simple approach by which the hard water that needs to be treated flows through a magnetic field. This field is created by inducing current in a coil wrapped around a pipe. Consequently some of its properties, such as total dissolved salts (TDS, conductivity (Ec and PH change. The primary purpose of hard water treatment is to decrease TDS in the incoming liquid stream. Using performance data from the application of different magnetic field densities on the different flow levels of water, empirical mathematical models were developed relating the salt removal percentage (SRP to operating flow rate and current of the coil. The obtained experimental results showed that the SRP increased with increasing the current at low flow rates (up to 0.75 ml/s.

  12. Camera-based measurement of respiratory rates is reliable.

    Science.gov (United States)

    Becker, Christoph; Achermann, Stefan; Rocque, Mukul; Kirenko, Ihor; Schlack, Andreas; Dreher-Hummel, Thomas; Zumbrunn, Thomas; Bingisser, Roland; Nickel, Christian H

    2017-06-01

    Respiratory rate (RR) is one of the most important vital signs used to detect whether a patient is in critical condition. It is part of many risk scores and its measurement is essential for triage of patients in emergency departments. It is often not recorded as measurement is cumbersome and time-consuming. We intended to evaluate the accuracy of camera-based measurements as an alternative measurement to the current practice of manual counting. We monitored the RR of healthy male volunteers with a camera-based prototype application and simultaneously by manual counting and by capnography, which was considered the gold standard. The four assessors were mutually blinded. We simulated normoventilation, hypoventilation and hyperventilation as well as deep, normal and superficial breathing depths to assess potential clinical settings. The volunteers were assessed while being undressed, wearing a T-shirt or a winter coat. In total, 20 volunteers were included. The results of camera-based measurements of RRs and capnography were in close agreement throughout all clothing styles and respiratory patterns (Pearson's correlation coefficient, r=0.90-1.00, except for one scenario, in which the volunteer breathed slowly dressed in a winter coat r=0.84). In the winter-coat scenarios, the camera-based prototype application was superior to human counters. In our pilot study, we found that camera-based measurements delivered accurate and reliable results. Future studies need to show that camera-based measurements are a secure alternative for measuring RRs in clinical settings as well.

  13. Interactions of Nitrogen Source and Rate and Weed Removal Timing Relative to Nitrogen Content in Corn and Weeds and Corn Grain Yield.

    Science.gov (United States)

    Knight, Alexandra M; Everman, Wesley J; Jordan, David L; Heiniger, Ronnie W; Smyth, T Jot

    2017-01-01

    Adequate fertility combined with effective weed management is important in maximizing corn (Zea mays L.) grain yield. Corn uptake of nitrogen (N) is dependent upon many factors including weed species and density and the rate and formulation of applied N fertilizer. Understanding interactions among corn, applied N, and weeds is important in developing management strategies. Field studies were conducted in North Carolina to compare corn and weed responses to urea ammonium nitrate (UAN), sulfur-coated urea (SCU), and composted poultry litter (CPL) when a mixture of Palmer amaranth (Amaranthus palmeri S. Wats.) and large crabgrass (Digitaria sanguinalis L.) was removed with herbicides at heights of 8 or 16 cm. These respective removal timings corresponded with 22 and 28 days after corn planting or V2 and V3 stages of growth, respectively. Differences in N content in above-ground biomass of corn were noted early in the season due to weed interference but did not translate into differences in corn grain yield. Interactions of N source and N rate were noted for corn grain yield but these factors did not interact with timing of weed control. These results underscore that timely implementation of control tactics regardless of N fertility management is important to protect corn grain yield.

  14. Interactions of Nitrogen Source and Rate and Weed Removal Timing Relative to Nitrogen Content in Corn and Weeds and Corn Grain Yield

    Directory of Open Access Journals (Sweden)

    Alexandra M. Knight

    2017-01-01

    Full Text Available Adequate fertility combined with effective weed management is important in maximizing corn (Zea mays L. grain yield. Corn uptake of nitrogen (N is dependent upon many factors including weed species and density and the rate and formulation of applied N fertilizer. Understanding interactions among corn, applied N, and weeds is important in developing management strategies. Field studies were conducted in North Carolina to compare corn and weed responses to urea ammonium nitrate (UAN, sulfur-coated urea (SCU, and composted poultry litter (CPL when a mixture of Palmer amaranth (Amaranthus palmeri S. Wats. and large crabgrass (Digitaria sanguinalis L. was removed with herbicides at heights of 8 or 16 cm. These respective removal timings corresponded with 22 and 28 days after corn planting or V2 and V3 stages of growth, respectively. Differences in N content in above-ground biomass of corn were noted early in the season due to weed interference but did not translate into differences in corn grain yield. Interactions of N source and N rate were noted for corn grain yield but these factors did not interact with timing of weed control. These results underscore that timely implementation of control tactics regardless of N fertility management is important to protect corn grain yield.

  15. Removal of gadolinium-based contrast agents: adsorption on activated carbon.

    Science.gov (United States)

    Elizalde-González, María P; García-Díaz, Esmeralda; González-Perea, Mario; Mattusch, Jürgen

    2017-03-01

    Three carbon samples were employed in this work, including commercial (1690 m 2  g -1 ), activated carbon prepared from guava seeds (637 m 2  g -1 ), and activated carbon prepared from avocado kernel (1068 m 2  g -1 ), to study the adsorption of the following gadolinium-based contrast agents (GBCAs): gadoterate meglumine Dotarem®, gadopentetate dimeglumine Magnevist®, and gadoxetate disodium Primovist®. The activation conditions with H 3 PO 4 were optimized using a Taguchi methodology to obtain mesoporous materials. The best removal efficiency by square meter in a batch system in aqueous solution and model urine was achieved by avocado kernel carbon, in which mesoporosity prevails over microporosity. The kinetic adsorption curves were described by a pseudo-second-order equation, and the adsorption isotherms in the concentration range 0.5-6 mM fit the Freundlich equation. The chemical characterization of the surfaces shows that materials with a greater amount of phenolic functional groups adsorb the GBCA better. Adsorption strongly depends on the pH due to the combination of the following factors: contrast agent protonated forms and carbon surface charge. The tested carbon samples were able to adsorb 70-90% of GBCA in aqueous solution and less in model urine. This research proposes a method for the elimination of GBCA from patient urine before its discharge into wastewater.

  16. A dipeptide-based superhydrogel: Removal of toxic dyes and heavy metal ions from waste water.

    Science.gov (United States)

    Nandi, Nibedita; Baral, Abhishek; Basu, Kingshuk; Roy, Subhasish; Banerjee, Arindam

    2017-01-01

    A short peptide-based molecule has been found to form a strong hydrogel at phosphate buffer solution of pH 7.46. The hydrogel has been characterized thoroughly using various techniques including field emission scanning electron microscopy (FE-SEM), wide angle powder X-ray diffraction (PXRD), and rheological analysis. It has been observed from FE-SEM images that entangled nanofiber network is responsible for gelation. Rheological investigation demonstrates that the self-assembly of this synthetic dipeptide results in the formation of mechanically strong hydrogel with storage modulus (G') around 104 Pa. This gel has been used for removing both cationic and anionic toxic organic dyes (Brilliant Blue, Congo red, Malachite Green, Rhodamine B) and metal ions (Co2+ and Ni2+ ) from waste water. Moreover, only a small amount of the gelator is required (less than 1 mg/mL) for preparation of this superhydrogel and even this hydrogel can be reused three times for dye/metal ion absorption. This signifies the importance of the hydrogel towards waste water management. © 2016 Wiley Periodicals, Inc.

  17. Neural networks-based modeling applied to a process of heavy metals removal from wastewaters.

    Science.gov (United States)

    Suditu, Gabriel D; Curteanu, Silvia; Bulgariu, Laura

    2013-01-01

    This article approaches the problem of environment pollution with heavy metals from disposal of industrial wastewaters, namely removal of these metals by means of biosorbents, particularly with Romanian peat (from Poiana Stampei). The study is carried out by simulation using feed-forward and modular neural networks with one or two hidden layers, pursuing the influence of certain operating parameters (metal nature, sorbent dose, pH, temperature, initial concentration of metal ion, contact time) on the amount of metal ions retained on the unit mass of sorbent. In neural network modeling, a consistent data set was used, including five metals: lead, mercury, cadmium, nickel and cobalt, the quantification of the metal nature being done by its electronegativity. Even if based on successive trials, the method of designing neural models was systematically conducted, recording and comparing the errors obtained with different types of neural networks, having various numbers of hidden layers and neurons, number of training epochs, or using various learning methods. The errors with values under 5% make clear the efficiency of the applied method.

  18. Adsorptive removal of anionic dyes from aqueous solutions using microgel based on nanocellulose and polyvinylamine.

    Science.gov (United States)

    Jin, Liqiang; Sun, Qiucun; Xu, Qinghua; Xu, Yongjian

    2015-12-01

    A novel nanocomposite microgel based on nanocellulose and amphoteric polyvinylamine (PVAm) was fabricated via a two-step method. Firstly, cellulose nanocrystal was oxidized by sodium periodate to yield dialdehyde nanocellulose (DANC). DANC was then used as a crosslinker to react with PVAm to obtain a pH responsive microgel with high density of free amine groups. The microgel was characterized using FTIR, XRD, AFM and elemental analysis. AFM images revealed that the nanocomposite was microspherical particles with a diameter ranging from 200 to 300nm. The microgel was found to be effective in anionic dye removal at acidic conditions. The adsorption isotherms for congo red 4BS, acid red GR and reactive light yellow K-4G fit well with the Sips model, and the maximum adsorption capacities were 869.1mgg(-1), 1469.7mgg(-1) and 1250.9mgg(-1), respectively. The adsorption for these three anionic dyes all followed pseudo second order kinetics, indicating a chemisorption nature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Muscle activity and masticatory efficiency with bilateral extension base removable partial dentures with different cusp angles.

    Science.gov (United States)

    Al-Omiri, Mahmoud K

    2017-06-20

    Whether masticatory efficiency and electromyographic activity are influenced by type of artificial teeth and food is unclear. The purpose of this clinical study was to evaluate the influence of extension base removable partial dentures (RPDs) with different cusp angles: anatomic (33 degrees), semianatomic (20 degrees), and nonanatomic (0 degrees) teeth on masticatory efficiency and muscle activity during the mastication of test foods with different textures. Twelve participants with RPDs were selected to perform masticatory efficiency and electromyographic tests. Surface electromyograms (EMGs) were used to record the activities of the masseter and temporalis muscles during the mastication of different types of test foods. The maximal voltage and duration were measured on the integrated EMG signal in each muscle during food mastication, and the mean reading of both sides was then recorded. Analysis of variance and the Tukey post hoc test were used to perform statistical analyses (α=.05). The masticatory efficiency of RPDs with nonanatomic teeth was significantly inferior to that of RPDs with anatomic and semianatomic teeth (P.05). Also, muscle activity (according to EMG) with RPDs with NA teeth was significantly higher than that with anatomic and semianatomic teeth (PEMG muscle activity and reduced masticatory efficiency than anatomic or semianatomic teeth. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  20. Polymer-based adsorbent for heavy metals removal from aqueous solution

    Science.gov (United States)

    Mahmud, H. N. M. E.; Huq, A. K. O.; Yahya, R.

    2017-06-01

    A novel conducting polymer-based adsorbent, polypyrrole (PPy) fine powder has successfully been prepared as a new adsorbent and utilized in the adsorption of heavy metal ions like arsenic, zinc and cadmium ions from aqueous solution. PPy was chemically synthesized by using FeCl3.6H2O as an oxidant. The prepared PPy adsorbent was characterized by Brunauer-Emmet-Teller (BET) surface analysis, field emission scanning electron microscopy (FESEM) and attenuated total reflectance fourier transform infrared ATR-(FTIR) spectroscopy. The adsorption was conducted by varying different parameters such as, contact time, pH and adsorbent dosage. The concentrations of metal ions were measured by inductively coupled plasma mass spectroscopy (ICP-MS). The results show that PPy acts as an effective sorbent for the removal of arsenic, zinc and cadmium ions from aqueous solution. The as-prepared PPy fine powder is easy to prepare and appeared as an effective adsorbent for heavy metal ions particularly arsenic in wastewater treatment.

  1. Evaluating the efficiency of humic acid to remove micro-organisms from denture base material.

    Science.gov (United States)

    Meriç, Gökçe; Güvenir, Meryem; Süer, Kaya

    2016-09-01

    To evaluate the efficiency of humic acid substances on removing micro-organisms from denture base materials. Old denture wearer needs effective, easy-use and safe denture-cleaning material. Square-shaped, heat-polymerised acrylic resin specimens (n = 550) were prepared and divided into five groups (n = 110 for each) corresponding to the microbial contamination (Candida albicans, Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis, Pseudomonas aeruginosa). Contaminated specimens were randomly assigned to the application of five different denture-cleaning agents as follows (n = 20 for each): Kloroben, Corsodyl, Steradent, Corega, experimental solution with humic acid. Ten specimens were assessed as an experimental control carried out simultaneously for the treatment groups for each micro-organism. It was divided into two groups: negative control and positive control (n = 5 for each). All acrylic specimens were incubated 37°C for 24 h (for bacterial strains) and 37°C for 48 h (for yeast strains). After incubation period, all brain-heart infusion broths (BHI) which contain disinfectant acrylic specimens were cultured on 5% sheep blood agar (for bacteria) and Sabouraud dextrose agar (SDA) for yeast using loop. The numbers of colony-forming units per millilitre (CFU/ml) were calculated. The results were analysed by Mann-Whitney U-test and Kruskal-Wallis tests (p = 0.05). Corsodyl and Kloroben completely eliminated the adherence of all investigated micro-organisms (100%) and showed the highest removal activity compared with other cleaning agents (p < 0.05). There was no statistically significant difference between Corsodyl and Kloroben (p ≥ 0.05), and there was no statistically significant difference between Corega, Steradent and experimental solution (p ≥ 0.05). Humic acid could be used as an alternative 'natural' solution for denture-cleaning agent. © 2014 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley

  2. Reduced rate of intensive care unit acquired gram-negative bacilli after removal of sinks and introduction of ‘water-free’ patient care

    Directory of Open Access Journals (Sweden)

    Joost Hopman

    2017-06-01

    Full Text Available Abstract Background Sinks in patient rooms are associated with hospital-acquired infections. The aim of this study was to evaluate the effect of removal of sinks from the Intensive Care Unit (ICU patient rooms and the introduction of ‘water-free’ patient care on gram-negative bacilli colonization rates. Methods We conducted a 2-year pre/post quasi-experimental study that compared monthly gram-negative bacilli colonization rates pre- and post-intervention using segmented regression analysis of interrupted time series data. Five ICUs of a tertiary care medical center were included. Participants were all patients of 18 years and older admitted to our ICUs for at least 48 h who also received selective digestive tract decontamination during the twelve month pre-intervention or the twelve month post-intervention period. The effect of sink removal and the introduction of ‘water-free’ patient care on colonization rates with gram-negative bacilli was evaluated. The main outcome of this study was the monthly colonization rate with gram-negative bacilli (GNB. Yeast colonization rates were used as a ‘negative control’. In addition, colonization rates were calculated for first positive culture results from cultures taken ≥3, ≥5, ≥7, ≥10 and ≥14 days after ICU-admission, rate ratios (RR were calculated and differences tested with chi-squared tests. Results In the pre-intervention period, 1496 patients (9153 admission days and in the post-intervention period 1444 patients (9044 admission days were included. Segmented regression analysis showed that the intervention was followed by a statistically significant immediate reduction in GNB colonization in absence of a pre or post intervention trend in GNB colonization. The overall GNB colonization rate dropped from 26.3 to 21.6 GNB/1000 ICU admission days (colonization rate ratio 0.82; 95%CI 0.67–0.99; P = 0.02. The reduction in GNB colonization rate became more pronounced in patients

  3. The long-term effect of nitrite on the granule-based enhanced biological phosphorus removal system and the reversibility.

    Science.gov (United States)

    Zheng, Xiongliu; Sun, Peide; Lou, Juqing; Fang, Zhiguo; Guo, Maoxin; Song, Yingqi; Tang, Xiudi; Jiang, Tao

    2013-03-01

    This study investigated the long-term effect of nitrite on the granule-based enhanced biological phosphorus removal (EBPR) system and the reversibility from macro- to micro-scale. Nitrite was found to seriously deteriorate the EBPR performance and result in severe sludge bulking. The inhibited polysaccharides excretion could lead to breaking the stability and integrity of the granules. Therefore, the reduced particle size and granule disintegration were observed. In this study, granules with lower ratio of proteins to polysaccharides (1.76) had better structure and function than the higher (3.84). Experimental results demonstrated that the microbial community structure was largely changed due to the presence of nitrite. In comparison, glycogen accumulating organisms (GAOs) had stronger resistibility and higher recovery rate than poly-phosphate accumulating organisms (PAOs). Interestingly, the community composition was unable to recover (Dice coefficients, 33.0%), although good EBPR performance was achieved only by propagating other types of PAOs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Fabrication of the novel hydrogel based on waste corn stalk for removal of methylene blue dye from aqueous solution

    Science.gov (United States)

    Ma, Dongzhuo; Zhu, Baodong; Cao, Bo; Wang, Jian; Zhang, Jianwei

    2017-11-01

    The novel hydrogel based on waste corn stalk was synthetized by aqueous solution polymerization technique with functional monomers in the presence of organic montmorillonite (OMMT) under ultrasonic. In this study, batch adsorption experiments were carried out to research the effect of initial dye concentration, the dosage of hydrogel, stirring speed, contact time and temperature on the adsorption of methylene blue (MB) dye. The adsorption process was best described by the pseudo-second-order kinetic model, which confirmed that it should be a chemical process. Furthermore, we ascertained the rate controlling step by establishing the intraparticle diffusion model and the liquid film diffusion model. The adsorption and synthesis mechanisms were vividly depicted in our work as well. Structural and morphological characterizations by virtue of FTIR, FESEM, and Biomicroscope supported the relationship between the adsorption performance and material's microstructure. This research is a valuable contribution for the environmental protection, which not only converts waste corn stalks into functional materials, but improves the removal of organic dye from sewage water.

  5. Removal of residual palm oil-based biodiesel catalyst using membrane ultra-filtration technique: An optimization study

    Directory of Open Access Journals (Sweden)

    I.M. Atadashi

    2014-09-01

    Full Text Available In this research work, residual potassium hydroxide catalyst was removed from palm oil-based alkyl esters (biodiesel using membrane separative technique, with the aim of achieving high-quality biodiesel that meets international standard specifications. Further, Central Composite Design (CCD coupled with Response Surface Methodology (RSM was employed to study the effects of the system variables such as flow rate, temperature and transmembrane pressure (TMP on the retention of potassium. At the optimum conditions, the coefficient of retention (%R of the catalyst was 93.642, and the content of the potassium was reduced from 8.328 mg/L to 0.312 mg/L; a value well below the one specified by both EN 14214 and ASTM D6751 standards. In addition, the comparison between predicted and experimental values for the catalyst retention offers a reasonable percentage error of 0.081%. Therefore, this study has proven that membrane technique can be used to post treat crude biodiesel; in order to achieve high-quality biodiesel fuel that can be efficiently used on diesel engines.

  6. Evaluation of the metabolic rate based on the recording of the heart rate.

    Science.gov (United States)

    Malchaire, Jacques; d'AMBROSIO Alfano, Francesca Romana; Palella, Boris Igor

    2017-06-08

    The assessment of harsh working conditions requires a correct evaluation of the metabolic rate. This paper revises the basis described in the ISO 8996 standard for the evaluation of the metabolic rate at a work station from the recording of the heart rate of a worker during a representative period of time. From a review of the literature, formulas different from those given in the standard are proposed to estimate the maximum working capacity, the maximum heart rate, the heart rate and the metabolic rate at rest and the relation (HR vs. M) at the basis of the estimation of the equivalent metabolic rate, as a function of the age, height and weight of the person. A Monte Carlo simulation is used to determine, from the approximations of these parameters and formulas, the imprecision of the estimated equivalent metabolic rate. The results show that the standard deviation of this estimate varies from 10 to 15%.

  7. A systematic review of light-based home-use devices for hair removal and considerations on human safety.

    Science.gov (United States)

    Thaysen-Petersen, D; Bjerring, P; Dierickx, C; Nash, J F; Town, G; Haedersdal, M

    2012-05-01

    Hair removal with professional light-based devices is established as an effective, mainstream treatment. The field of optical home-based hair removal is evolving and movement from control by physicians into hands of consumers warrants understanding efficacy and human safety. To systematically review and evaluate the efficacy and human safety of currently available home-based optical hair removal devices. A comprehensive Pub Med literature search was conducted which systematically identified publications of relevance. Prospective clinical trials were included whether controlled, uncontrolled or randomized and with a sample size of at least 10 individuals. We identified a total of seven studies: one controlled (CT) and six uncontrolled trials (UCTs). No randomized controlled trials (RCT) were recognized. The best evidence was found for IPL (intense pulsed light) (three devices, one CT, five UCTs) and limited evidence for laser devices (one diode laser, one UCT). Most studies evaluated short-term hair reduction up to 3 and 6 months following light exposure at different body sites. Hair reduction percentages ranged from 6% to 72% after repetitive treatments. The most frequently reported side-effect was erythema, but oedema, blistering, crusting and pigment changes were also reported. Theoretical concerns about ocular damage and paradoxical hair growth have not been reported in any of the studies reviewed. Available evidence from prospective, uncontrolled clinical trials indicates short-term hair removal efficacy of currently available home-use light-based hair removal devices. Additional controlled trials will be helpful to substantiate the efficacy and to better predict the incidence of adverse events associated with optical home-use hair removal. © 2011 The Authors. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.

  8. HEART-RATE-VARIABILITY SPECTRA BASED ON NONEQUIDISTANT SAMPLING - THE SPECTRUM OF COUNTS AND THE INSTANTANEOUS HEART-RATE SPECTRUM

    NARCIS (Netherlands)

    VANSTEENIS, HG; TULEN, JHM; MULDER, LJM

    This paper compares two methods to estimate heart rate variability spectra i.e., the spectrum of counts and the instantaneous heart rate spectrum. Contrary to Fourier techniques based on equidistant sampling of the interbeat intervals, the spectrum of counts of the instantaneous heart rate spectrum

  9. A prototype of novel agro-waste based column bed device for removal of textile dye Optilan Red.

    Science.gov (United States)

    Gita, Samchetshabam; Shukla, S P; Choudhury, T G; Prakash, C; Singh, A R

    2017-09-01

    The aim of the study was to assess the potentiality of an agro-waste (sugarcane bagasse) for removal of the textile dye (Optilan Red) using novel column based filtration unit with a packed column of chemically treated sugarcane bagasse. The treated and untreated sugarcane bagasse (biosorbent) were characterized by Fourier transform infrared (FT-IR) spectroscopy. Effect of initial dye concentration on percentage removal of dye, equilibrium adsorption of sugarcane bagasse, kinetic studies, breakthrough point equilibrium and desorption of dye from the column material were studied. An inverse dependence of initial dye concentration on percent removal of dye was observed, whereas the equilibrium adsorption (q e ) showed a direct relationship with dye concentration. The time required for reaching breakthrough point was 120 min. Desorption of dye through alkali wash resulted in complete desorption after 1 h washing of the column for its reuse for next cycle. FT-IR analysis shows vibration in valence bands of the hydrogen bond of OH group, and the bands of intra-molecular and intermolecular hydrogen bonds, which results in interaction of treated bagasse with Optilan Red textile dye. The present study showed that more than 93% removal of the dye can be achieved in the concentration range 10-50 ppm (aqueous solution). The removal efficiency of the column remained almost unchanged for the treatment of dye-house wastewater spiked with the dye. The agro-waste based treatment process shows a considerable potential for a low-cost treatment of dye contaminated water.

  10. Smartphone-based photoplethysmographic imaging for heart rate monitoring.

    Science.gov (United States)

    Alafeef, Maha

    2017-07-01

    The purpose of this study is to make use of visible light reflected mode photoplethysmographic (PPG) imaging for heart rate (HR) monitoring via smartphones. The system uses the built-in camera feature in mobile phones to capture video from the subject's index fingertip. The video is processed, and then the PPG signal resulting from the video stream processing is used to calculate the subject's heart rate. Records from 19 subjects were used to evaluate the system's performance. The HR values obtained by the proposed method were compared with the actual HR. The obtained results show an accuracy of 99.7% and a maximum absolute error of 0.4 beats/min where most of the absolute errors lay in the range of 0.04-0.3 beats/min. Given the encouraging results, this type of HR measurement can be adopted with great benefit, especially in the conditions of personal use or home-based care. The proposed method represents an efficient portable solution for HR accurate detection and recording.

  11. Base rates of hate crime victimization among college students.

    Science.gov (United States)

    Rayburn, Nadine Recker; Earleywine, Mitchell; Davison, Gerald C

    2003-10-01

    This study uses the unmatched count technique (UCT) to estimate base rates for hate crime victimization in college students and compares the results with estimates found using conventional methods. Hate crimes, criminal acts perpetrated against individuals or members of specific stigmatized groups, intend to express condemnation, hate, disapproval, dislike, or distrust for a group. The UCT is a promising tool in the investigation of hate crime because it does not require participants to directly answer sensitive questions. This may provide more accurate responses than other methods. The UCT revealed higher estimates for a variety of serious hate crimes, including physical and sexual assault. These higher estimates provide a better feel for the level of hate crime victimization and point to the increased need for hate crime victims' assistance programs on college campuses.

  12. Optimization of Surface Acoustic Wave-Based Rate Sensors

    Directory of Open Access Journals (Sweden)

    Fangqian Xu

    2015-10-01

    Full Text Available The optimization of an surface acoustic wave (SAW-based rate sensor incorporating metallic dot arrays was performed by using the approach of partial-wave analysis in layered media. The optimal sensor chip designs, including the material choice of piezoelectric crystals and metallic dots, dot thickness, and sensor operation frequency were determined theoretically. The theoretical predictions were confirmed experimentally by using the developed SAW sensor composed of differential delay line-oscillators and a metallic dot array deposited along the acoustic wave propagation path of the SAW delay lines. A significant improvement in sensor sensitivity was achieved in the case of 128° YX LiNbO3, and a thicker Au dot array, and low operation frequency were used to structure the sensor.

  13. Evaluation of the metabolic rate based on the recording of the heart rate

    OpenAIRE

    MALCHAIRE, Jacques; ALFANO, Francesca Romana d?AMBROSIO; PALELLA, Boris Igor

    2017-01-01

    The assessment of harsh working conditions requires a correct evaluation of the metabolic rate. This paper revises the basis described in the ISO 8996 standard for the evaluation of the metabolic rate at a work station from the recording of the heart rate of a worker during a representative period of time. From a review of the literature, formulas different from those given in the standard are proposed to estimate the maximum working capacity, the maximum heart rate, the heart rate and the me...

  14. Mecoprop (MCPP) removal in full-scale rapid sand filters at a groundwater-based waterworks

    DEFF Research Database (Denmark)

    Hedegaard, Mathilde Jørgensen; Arvin, Erik; Corfitzen, Charlotte B.

    2014-01-01

    Contamination by the herbicide mecoprop (MCPP) was detected in groundwater abstraction wells at Kerteminde Waterworks in concentrations up to 0.08μg/L. MCPP was removed to below detection limit in a simple treatment line where anaerobic groundwater was aerated and subsequently filtered by primary.......It was concluded that MCPP was removed in secondary rapid sand filters at Kerteminde Waterworks, to which both adsorption and microbial degradation contributed....... in the full-scale system. Therefore, microcosms were set up with filter sand, water and 14C-labelled MCPP at an initial concentration of 0.2μg/L. After 24h, 79–86% of the initial concentration of MCPP was removed. Sorption removed 11–15%, while the remaining part was removed by microbial processes, leading...... to a complete mineralisation of 13–18%. Microbial removal in the filter sand was similar at different depths of the rapid sand filter, while the amount of MCPP which adsorbed to the filter sand after 48h decreased with depth from 21% of the initial MCPP in the top layer to 7% in the bottom layer...

  15. Retrospective comparative ten-year study of cumulative survival rates of remaining teeth in large edentulism treated with implant-supported fixed partial dentures or removable partial dentures.

    Science.gov (United States)

    Yamazaki, Seiya; Arakawa, Hikaru; Maekawa, Kenji; Hara, Emilio Satoshi; Noda, Kinji; Minakuchi, Hajime; Sonoyama, Wataru; Matsuka, Yoshizo; Kuboki, Takuo

    2013-07-01

    This study aimed to compare the survival rates of remaining teeth between implant-supported fixed dentures (IFDs) and removable partial dentures (RPDs) in patients with large edentulous cases. The second goal was to assess the risk factors for remaining tooth loss. The study subjects were selected among those who received prosthodontic treatment at Okayama University Dental Hospital for their edentulous space exceeding at least four continuous missing teeth. Twenty-one patients were included in the IFD group and 82 patients were included in the RPD group. Survival rates of remaining teeth were calculated in three subcategories: (1) whole remaining teeth, (2) adjacent teeth to intended edentulous space, and (3) opposing teeth to intended edentulous space. The ten-year cumulative survival rate of the whole remaining teeth was significantly higher in the IFD group (40.0%) than in the RPD group (24.4%). On the other hand, there was no significant difference between two groups in the survival rate of teeth adjacent or opposing to intended edentulous space. A Cox proportional hazard analysis revealed that RPD restoration and gender (male) were the significant risk factors for remaining tooth loss (whole remaining teeth). These results suggest that IFD treatment can reduce the incidence of remaining tooth loss in large edentulous cases. Copyright © 2013 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  16. EVALUATION OF TWO LEAD-BASED PAINT REMOVAL AND WASTE STABILIZATION TECHNOLOGY COMBINATIONS ON TYPICAL EXTERIOR SURFACES

    Science.gov (United States)

    A study was conducted to demonstrate the effectiveness of a wet abrasive blasting technology to remove lead-based paint from exterior wood siding and brick substrates as well as to evaluate the effectiveness of two waste stabilization technologies to stabilize the resulting blast...

  17. Utilization of Anabaena sp. in CO{sub 2} removal processes. Modelling of biomass, exopolysaccharides productivities and CO{sub 2} fixation rate

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Fernandez, J.F.; Gonzalez-Lopez, C.V.; Acien Fernandez, F.G.; Fernandez Sevilla, J.M.; Molina Grima, E. [Almeria Univ. (Spain). Dept. of Chemical Engineering

    2012-05-15

    This paper focuses on modelling the growth rate and exopolysaccharides production of Anabaena sp. ATCC 33047, to be used in carbon dioxide removal and biofuels production. For this, the influence of dilution rate, irradiance and aeration rate on the biomass and exopolysaccharides productivity, as well as on the CO{sub 2} fixation rate, have been studied. The productivity of the cultures was maximum at the highest irradiance and dilution rate assayed, resulting to 0.5 g{sub bio} l{sup -1} day{sup -1} and 0.2 g{sub eps} l{sup -1} day{sup -1}, and the CO{sub 2} fixation rate measured was 1.0 gCO{sub 2} l{sup -1} day{sup -1}. The results showed that although Anabaena sp. was partially photo-inhibited at irradiances higher than 1,300 {mu}E m-2 s{sup -1}, its growth rate increases hyperbolically with the average irradiance inside the culture, and so does the specific exopolysaccharides production rate. The latter, on the other hand, decreases under high external irradiances, indicating that the exopolysaccharides metabolism hindered by photo-damage. Mathematical models that consider these phenomena have been proposed. Regarding aeration, the yield of the cultures decreased at rates over 0.5 v/v/min or when shear rates were higher than 60 s{sup -1}, demonstrating the existence of thus existence of stress damage by aeration. The behaviour of the cultures has been verified outdoors in a pilot-scale airlift tubular photobioreactor. From this study it is concluded that Anabaena sp. is highly recommended to transform CO{sub 2} into valuable products as has been proved capable of metabolizing carbon dioxide at rates of 1.2 gCO{sub 2} l{sup -1} day{sup -1} outdoors. The adequacy of the proposed equations is demonstrated, resulting to a useful tool in the design and operation of photobioreactors using this strain. (orig.)

  18. Simultaneous removal and evaluation of organic substrates and NH{sub 3}-N by a novel combined process in treating chemical synthesis-based pharmaceutical wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhaobo [School of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Wang, Hongcheng [School of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Ren, Nanqi, E-mail: rnq@hit.edu.cn [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China); Cui, Minhua; Nie, Shukai; Hu, Dongxue [School of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer We research a novel combined process to treat chemical synthesis-based pharmaceutical wastewater. Black-Right-Pointing-Pointer The mechanism of amoxicillin verifies that the biodegradation, adsorption, hydrolysis and unknown mechanism were able to remove amoxicillin from wastewater. Black-Right-Pointing-Pointer In this study demonstrates that biodegradation is the major factor for removal mechanism at work for amoxicillin. Black-Right-Pointing-Pointer Mathematical statistic methods were employed to evaluate the performance of the WWTP. - Abstract: A full-scale novel combined anaerobic/micro-aerobic and two-stage aerobic biological process is used for the treatment of an actual chemical synthesis-based pharmaceutical wastewater containing amoxicillin. The anaerobic system is an up-flow anaerobic sludge blanket (UASB), the micro-aerobic system is a novel micro-aerobic hydrolysis acidification reactor (NHAR) and the two-stage aerobic process comprised cyclic activated sludge system (CASS) and biological contact oxidation tank (BCOT). The influent wastewater was high in COD, NH{sub 3}-N varying daily 4016-13,093 mg-COD L{sup -1} and 156.4-650.2 mg-NH{sub 3}-N L{sup -1}, amoxicillin varying weekly between 69.1 and 105.4 mg-amoxicillin L{sup -1}, respectively; Almost all the COD, NH{sub 3}-N, amoxicillin were removed by the biological combined system, with removal percentages 97%, 93.4% and 97.2%, respectively, leaving around 104 mg-COD L{sup -1}, 9.4 mg-NH{sub 3}-N L{sup -1} and 2.6 {+-} 0.8 mg-amoxicillin L{sup -1} in the final clarifier effluent. The performance evaluation of the wastewater treatment plant (WWTP) by mathematical statistic methods shown that at most of time effluent can meet the higher treatment discharge standard. In addition, the fate of amoxicillin in the full-scale WWTP and the amoxicillin removal rate of each different removal routes in UASB, NHAR, CASS, BCOT and final clarifier processes are investigated

  19. Wavelet Transform Based Filter to Remove the Notches from Signal Under Harmonic Polluted Environment

    Science.gov (United States)

    Das, Sukanta; Ranjan, Vikash

    2017-12-01

    The work proposes to annihilate the notches present in the synchronizing signal required for converter operation appearing due to switching of semiconductor devices connected to the system in the harmonic polluted environment. The disturbances in the signal are suppressed by wavelet based novel filtering technique. In the proposed technique, the notches in the signal are determined and eliminated by the wavelet based multi-rate filter using `Daubechies4' (db4) as mother wavelet. The computational complexity of the adapted technique is very less as compared to any other conventional notch filtering techniques. The proposed technique is developed in MATLAB/Simulink and finally validated with dSPACE-1103 interface. The recovered signal, thus obtained, is almost free of the notches.

  20. Removal of selected emerging PPCP compounds using greater duckweed (Spirodela polyrhiza) based lab-scale free water constructed wetland.

    Science.gov (United States)

    Li, Jianan; Zhou, Qizhi; Campos, Luiza C

    2017-12-01

    Greater duckweed (Spirodela polyrhiza) based lab-scale free water constructed wetland (CW) was employed for removing four emerging pharmaceuticals and personal care products (PPCPs) (i.e. DEET, paracetamol, caffeine and triclosan). Orthogonal design was used to test the effect of light intensity, aeration, E.coli abundance and plant biomass on the target compounds. Synthetic wastewater contaminated with the target compounds at concentration of 25 μg/L was prepared, and both batch and continuous flow experiments were conducted. Up to 100% removals were achieved for paracetamol (PAR), caffeine (CAF) and tricolsan (TCS) while the highest removal for DEET was 32.2% in batch tests. Based on orthogonal Duncan analysis, high light intensity (240 μmolmm -2 s -1 ), full aeration, high plant biomass (1.00 kg/m 2 ) and high E.coli abundance (1.0 × 10 6  CFU/100 mL) favoured elimination of the PPCPs. Batch verification test achieved removals of 17.1%, 98.8%, 96.4% and 95.4% for DEET, PAR, CAF and TCS respectively. Continuous flow tests with CW only and CW followed by stabilization tank (CW-ST) were carried out. Final removals of the PPCP contaminants were 32.6%, 97.7%, 98.0% and 100% for DEET, PAR, CAF and TCS, respectively, by CW system alone, while 43.3%, 97.5%, 98.2% and 100%, respectively, were achieved by CW-ST system. By adding the ST tank, PPCP concentrations decreased significantly faster (p < 0.05) compared with continuous flow CW alone. In addition, after removing aerators during continuous flow CW experiments, the treatment systems presented good stability for the PPCP removals. CW-ST showed better chemical oxygen demand (COD) and total organic carbon (TOC) removals (89.3%, 91.2%, respectively) than CW only (79.4%, 85.2%, respectively). However, poor DEET removal (<50%) and high E.coli abundance (up to 1.7 log increase) in the final treated water indicated further treatment processes may be required. Statistical analysis showed significant correlations

  1. Removal of ionizable aromatic pollutants from contaminated water using nano γ-Fe2O3based magnetic cationic hydrogel: Sorptive performance, magnetic separation and reusability.

    Science.gov (United States)

    Khan, Musharib; Lo, Irene M C

    2017-01-15

    Acid dyes found in textile industrial effluents are hazardous aromatic pollutants which ionize in aqueous environments. Owing to their non-biodegradability, conventional wastewater treatment processes are not able to remove them and sorptive treatment systems can alternatively be employed. In this study, a nano γ-Fe 2 O 3 based magnetic cationic hydrogel, synthesized through a facile method, was applied for the removal of two acid dyes (Acid Red 27 and Acid Orange 52). The sorption performance (e.g., capacity and kinetics) and solution matrix effects (e.g., pH and competing anions) were investigated. Furthermore, different regeneration conditions (e.g., composition, strength and amount) were tested to develop a suitable regeneration strategy, based on which, reusability of the material was investigated for 30 consecutive sorption-desorption cycles. The material exhibited a rapid sorption rate (99% dye removal within 5min) and sorption isotherm data agreed well with the Langmuir model with an estimated maximum capacity of 833mg/g and 1430mg/g for Acid Red 27 and Acid Orange 52, respectively. The high sorptive performance persisted not only over a wide pH range but also over 30 consecutive rounds of sorption-desorption. Moreover, the impregnated γ-Fe 2 O 3 nanoparticles rendered the hydrogel superparamagnetic allowing its convenient magnetic separation. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Phenyl-functionalized magnetic palm-based powdered activated carbon for the effective removal of selected pharmaceutical and endocrine-disruptive compounds.

    Science.gov (United States)

    Wong, Kien Tiek; Yoon, Yeomin; Snyder, Shane A; Jang, Min

    2016-06-01

    Triethoxyphenylsilane (TEPS)-functionalized magnetic palm-based powdered activated carbon (MPPAC-TEPS) was prepared and characterized using various spectroscopic methods, and then tested for the removal of bisphenol A, carbamazepine, ibuprofen and clofibric acid. Magnetite film on MPPAC-TEPS was homogeneously coated on the outer surface of palm-based powdered activated carbon (PPAC) through a hydrothermal co-precipitation technique. Followed by silanization of phenyl-functionalized organosilane on MPPAC's magnetic film. As results, micro/mesopore surface area and volume increased without significant pore clogging and iron (Fe) dissolution under the acidic conditions was greatly decreased. The unique structural and chemical features of MPPAC-TEPS were found to be the main reasons for the enhanced adsorption rates and removal capacities of POPs. The presence of electrolytes and different pH values greatly affected the sorption efficiencies. The dominant sorption mechanism of POPs by MPPAC-TEPS was determined to be π-π interaction (physisorption), based on thermodynamic (ΔG°) and differential scanning calorimetry (DSC). Thermal regeneration at a low temperature (350 °C) was an effective method to desorb the retained POPs and enabled to reactivate MPPAC-TEPS with sustained sorption rates and capacities, whereas PPAC was largely exhausted. As a new type of sorbent for POPs, MPPAC-TEPS has operational advantages, such as magnetic separation and stable regeneration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. [Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio]. Volume 9, Removal action system design

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-01

    This Removal Action System Design has been prepared as a Phase I Volume for the implementation of the Phase II removal action at Wright-Patterson Air Force Base (WPAFB) near Dayton, Ohio. The objective of the removal action is to prevent, to the extent practicable, the migration of ground water contaminated with chlorinated volatile organic compounds (VOCS) across the southwest boundary of Area C. The Phase 1, Volume 9 Removal Action System Design compiles the design documents prepared for the Phase II Removal Action. These documents, which are presented in Appendices to Volume 9, include: Process Design, which presents the 30 percent design for the ground water treatment system (GWTS); Design Packages 1 and 2 for Earthwork and Road Construction, and the Discharge Pipeline, respectively; no drawings are included in the appendix; Design Package 3 for installation of the Ground Water Extraction Well(s); Design Package 4 for installation of the Monitoring Well Instrumentation; and Design Package 5 for installation of the Ground Water Treatment System; this Design Package is incorporated by reference because of its size.

  4. Hydrogen sulfide removal from sediment and water in box culverts/storm drains by iron-based granules.

    Science.gov (United States)

    Sun, J L; Shang, C; Kikkert, G A

    2013-01-01

    A renewable granular iron-based technology for hydrogen sulfide removal from sediment and water in box culverts and storm drains is discussed. Iron granules, including granular ferric hydroxide (GFH), granular ferric oxide (GFO) and rusted waste iron crusts (RWIC) embedded in the sediment phase removed aqueous hydrogen sulfide formed from sedimentary biological sulfate reduction. The exhausted iron granules were exposed to dissolved oxygen and this regeneration process recovered the sulfide removal capacities of the granules. The recovery is likely attributable to the oxidation of the ferrous iron precipitates film and the formation of new reactive ferric iron surface sites on the iron granules and sand particles. GFH and RWIC showed larger sulfide removal capacities in the sediment phase than GFO, likely due to the less ordered crystal structures on their surfaces. This study demonstrates that the iron granules are able to remove hydrogen sulfide from sediment and water in box culverts and storm drains and they have the potential to be regenerated and reused by contacting with dissolved oxygen.

  5. Removal of a low-velocity projectile from the base of the sphenoid sinus using navigation-guided endoscopy.

    Science.gov (United States)

    Verhaeghe, Wim; Schepers, Serge; Sun, Yi; Orye, Johan; Vrielinck, Luc; Lakiere, Eva; De Temmerman, Griet; Politis, Constantinus

    2012-03-01

    A patient surviving after a metal projectile penetrates the sphenoid sinus is unusual. Removing a foreign object from this region is challenging because of the difficult access and proximity to delicate structures. The use of navigation-guided endoscopy makes the manipulation of the surgical instruments near delicate structures safer, and the procedure is minimally invasive. A computed tomographic scan of brain showed the projectile located at the base of the left sphenoid sinus. To prevent infection and irritation and avoid secondary surgical damage, navigation-guided endoscopy was used to remove the bullet. Using the BRAINLAB navigation system, the movement of the endoscope could be followed on the screen, and the tip could be navigated into close contact with the projectile. The bullet could be located, without being visible through the endoscope, making the incision and removal of the bony wall of the sinus minimal; it was removed without complications. Intraoperative navigation of endoscopes is very useful because it enables the surgeon to correlate the visual information through the endoscope with the localization of the instruments seen on the navigation screen. Patient safety and reinforced self-confidence of surgeons are advantages of this procedure. Reduced operative time may not always occur because of a lack of experience with the navigation system. When there are no vascular or neurologic complications, a minimally invasive treatment using nasal navigation-guided endoscopic removal can limit the potential surgical damage.

  6. Modeling phosphate transport and removal in a compact bed filled with a mineral-based sorbent for domestic wastewater treatment.

    Science.gov (United States)

    Herrmann, Inga; Jourak, Amir; Gustafsson, Jon Petter; Hedström, Annelie; Lundström, T Staffan; Viklander, Maria

    2013-11-01

    Phosphorus filter units containing mineral-based sorbents with a high phosphate (PO4) binding capacity have been shown to be appropriate for removing PO4 in the treatment of domestic wastewater in on-site facilities. However, a better understanding of their PO4 removal mechanisms, and reactions that could lead to the formation of PO4 compounds, is required to evaluate the potential utility of candidate sorbents. Models based on data obtained from laboratory-scale experiments with columns of selected materials can be valuable for acquiring such understanding. Thus, in this study the transport and removal of PO4 in experiments with a laboratory-scale column filled with a commercial silicate-based sorbent were modeled, using the hydro-geochemical transport code PHREEQC. The resulting models, that incorporated the dissolution of calcite, kinetic constrains for the dissolution of calcium oxide (CaO) and wollastonite (CaSiO3), and the precipitation of amorphous tricalcium phosphate, Ca3(PO4)2, successfully simulated the removal of PO4 observed in the experiments. © 2013. Published by Elsevier B.V. All rights reserved.

  7. [Estimating glomerular filtration rate based on serum cystatin C].

    Science.gov (United States)

    Lü, Rui-Xue; Li, Yi-Song; Huang, Heng-Jian; Peng, Zhi-Ying; Ying, Bin-Wu; An, Zhen-Mei

    2012-01-01

    To develop an estimating formula for glomerular filtration Rate (GFR) based on serum cystatin C in patients with chronic kidney disease (CKD). Clinical characteristics of 242 CKD patients were collected. The patients were randomly divided into modeling group and model validation group. The rGFR obtained from 99mTc-DTPA clearance rate was used as a reference value of GFR. s-cystatin C was detected by latex enhanced immunoturbidimetric method. Preliminary linear regression analysis followed by multiple linear regression were performed to investigate the association between s-cystatin C and rGFR. The validity of the estimation formula was tested in the model validation group in comparison with Hoek formula and Orebro formula. With standardised countdown conversion, s-cystatin showed linear correlation with rGFR, with a correlation coefficient of 0.773. The multiple correlation coefficient, determination coefficient, adjusted R square and std. error of the estimation model were 0.863, 0.745, 0.742, and 0.207, respectively. The residuals P-P probability plot analysis showed that the model residuals fitted into normal distribution with homogeneity of variance. Theeformula was: eGFR = 67/s-cystatin C +3. No significant difference was found between the distribution of eGFR and rGFR. Our formula had an accuracy of 30% and 50%, which were no less than those obtained from Hoek formula and Orebro formula. The new formula also had acceptable bias and high precision. The Bland-Altman analysis and ROC curve analysis showed good applicability of the new formula. The GFR prediction formula we established has a good prediction performance as comparised with other formulae, which could be used in measuring GFR in CKD patients.

  8. Functionalized carbon nanotubes based filters for chromium removal from aqueous solutions.

    Science.gov (United States)

    Elsehly, Emad M; Chechenin, N G; Makunin, A V; Motaweh, H A; Leksina, E G

    2017-04-01

    This investigation examines the filtration efficiency of chromium from aqueous solution using two types of commercial multiwalled carbon nanotubes (MWCNTs) (Taunit-M (TM) and Taunit-MD (TMD)). These MWCNTs were modified using two complementary treatments, purification (using a mixture of hydrochloric acid and hydrogen peroxide) and functionalization (using nitric acid). The effect of these treatments on the morphology of MWCNT Taunit filters was characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy to estimate the outer diameter distribution and element content deposited on filters. Effects of different parameters, i.e., carbon nanotube filter mass, concentration of chromium in aqueous solution, and pH of aqueous solution, on removal of this heavy metal were determined. From these investigations, the removal efficiency of chromium could reach 97% for modified TM and 70% for modified TMD at concentration of 10 ppm, suggesting that modified TM is an excellent adsorbent for chromium removal from aqueous solutions and more efficient than modified TMD. A significant increase in chromium removal by modified TM at pH = 2 has been observed compared with higher pH values. It was found that modified TM filters can be reused through many cycles of regeneration with high performance. Modified TM filters may be a promising candidate for heavy metal ion removal from industrial wastewater.

  9. An EGSB-SBR based process for coupling methanogenesis and shortcut nitrogen removal.

    Science.gov (United States)

    Bai, Cui; Zhang, Daijun; He, Qiang; Lu, Peili; Ai, Hainan

    2013-01-01

    An integrated process consisting of an anaerobic/anoxic expanded granular sludge bed (EGSB) reactor and an aerobic sequencing batch reactor (SBR) was developed by a mode of sequencing batch operation, in which methanogenesis, denitrification and anammox were coupled in EGSB with methanogenesis first, then denitrification and anammox simultaneously, and partial nitrification occurred in SBR for providing nitrite to EGSB. This process extended the application of the anammox process to the treatment of wastewater containing high concentrations of chemical oxygen demand (COD) and ammonium. When the volumetric exchange ratio between EGSB and SBR was controlled at 57% with the influent pH at 6-8, 74.38-83.65% of NH(4)(+)-N, 72.68-83.12% of total nitrogen (TN) and 88.34-98.86% of COD were removed in a range of 200-4,500 mg/L COD and 40-90 mg/L NH(4)(+)-N respectively. TN removal by anammox and shortcut denitrification was 26.35-58.64 and 0-32.80% of the removed nitrogen, respectively. The results showed that the contribution of anammox gradually decreased with an increase in the C/N ratio of influent, whereas the reverse was true for shortcut denitrification. The COD removal by methanogenesis was 70.89-98.79% of the removed COD, and increased with increasing C/N ratio.

  10. Characterizing the Effects of Micro Electrical Discharge Machining Parameters on Material Removal Rate during Micro EDM Drilling of Tungsten Carbide (WC-Co)

    Science.gov (United States)

    Hourmand, Mehdi; Sarhan, Ahmed A. D.; Sayuti, Mohd

    2017-10-01

    Micro-dies, molds and miniaturized products can be manufactured using micro EDM process. In this research, EDM machine and on-machine fabricated CuW micro-electrode were utilized to produce the micro holes in WC-16%Co. The effects of voltage, current, pulse ON time, pulse OFF time, capacitor and rotating speed on Material removal rate (MRR) during micro EDM drilling of WC-16% Co was analyzed using fractional factorial design method. ANOVA analysis shows that increasing current, rotating speed, capacitor and decreasing voltage and pulse ON time lead to the amplify in MRR. It was found that out of all the factors, current and capacitor had the most significant effect on MRR, while the effect of capacitor was more than current. Eventually, it can be concluded that micro holes can be produced using EDM machine.

  11. Breath-hold after forced expiration before removal of the biopsy needle decreased the rate of pneumothorax in CT-guided transthoracic lung biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Min, Lingfeng; Xu, Xingxiang [Subei People' s Hospital of Jiangsu Province, Clinical Medical School of Yangzhou University, Yangzhou 225001, Jiangsu (China); Song, Yong [Jinling Hospital, Nanjing University School of Medical, Nanjing 210002, Jiangsu (China); Issahar, Ben-Dov [Pulmonary Institute, Sheba Medical Center, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv (Israel); Wu, Jingtao; Zhang, Le; Huang, Qian [Subei People' s Hospital of Jiangsu Province, Clinical Medical School of Yangzhou University, Yangzhou 225001, Jiangsu (China); Chen, Mingxiang, E-mail: chenmx1129@126.com [Subei People' s Hospital of Jiangsu Province, Clinical Medical School of Yangzhou University, Yangzhou 225001, Jiangsu (China)

    2013-01-15

    Purpose: To assess the effect of a breath-hold after forced expiration on the rate of pneumothorax after computed tomography (CT)-guided transthoracic needle biopsy of pulmonary lesions. Materials and methods: Between January 2008 and December 2011, percutaneous CT-guided lung biopsy was performed in 440 patients. Two hundred and twenty-one biopsies were performed without (control group) and two hundred and nineteen biopsies were performed with (study group) the study maneuver – a breath-hold after forced expiratory approach. Multivariate analysis was performed between groups for risk factors for pneumothorax, including patient demographics, lesion characteristics, and biopsy technique. Results: A reduced number of pneumothoraces (18 [8.2%] vs 35 [15.8%]; P = 0.014) but no significant difference in rate of drainage catheter insertions (2 [0.9%] vs (4 [1.8%]; P = 0.418) were noted in the study group as compared with the control group. By logistic regression analysis, three factors significantly and independently affected the risk for pneumothorax including lesion size (transverse and longitudinal diameter), distance from pleura and utilizing or avoiding the breath-hold after deep expiration maneuver. Conclusion: Breath-holding after forced expiration before removal of the biopsy needle during the percutaneous CT-guided transthoracic lung biopsy almost halved the rate of overall pneumothorax. Small lesion size (longitudinal diameter) and the distance from pleura were also predictors of pneumothorax in our study.

  12. Removal of metals from industrial wastewater and urban runoff by mineral and bio-based sorbents.

    Science.gov (United States)

    Gogoi, Harshita; Leiviskä, Tiina; Heiderscheidt, Elisangela; Postila, Heini; Tanskanen, Juha

    2018-03-01

    The study was performed to evaluate chemically modified biosorbents, hydrochloric acid treated peat (HCl-P) and citric acid treated sawdust (Citric acid-SD) for their metal removal capacity from dilute industrial wastewater and urban runoff and compare their efficiency with that of commercially available mineral sorbents (AQM PalPower M10 and AQM PalPower T5M5 magnetite). Batch and column experiments were conducted using real water samples to assess the sorbents' metal sorption capacity. AQM PalPower M10 (consisting mainly of magnesium, iron and silicon oxides) exhibited excellent Zn removal from both industrial wastewater and spiked runoff water samples even at low dosages (0.1 g/L and 0.05 g/L, respectively). The high degree of Zn removal was associated with the release of hydroxyl ions from the sorbent and subsequent precipitation of zinc hydroxide. The biosorbents removed Ni and Cr better than AQM PalPower M10 from industrial wastewater and performed well in removing Cr and Cu from spiked runoff water, although at higher dosages (0.3-0.75 g/L). The main mechanism of sorption by biosorbents was ion exchange. The sorbents required a short contact time to reach equilibrium (15-30 min) in both tested water samples. AQM PalPower T5M5 magnetite was the worst performing sorbent, leaching Zn into both industrial and runoff water and Ni into runoff water. Column tests revealed that both HCl-P and AQM PalPower M10 were able to remove metals, although some leaching was witnessed, especially As from AQM PalPower M10. The low hydraulic conductivity observed for HCl-P may restrict the possibilities of using such small particle size peat material in a filter-type passive system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Evidence based decontamination protocols for the removal of external Δ9-tetrahydrocannabinol (THC) from contaminated hair.

    Science.gov (United States)

    Duvivier, Wilco F; Peeters, Ruth J P; van Beek, Teris A; Nielen, Michel W F

    2016-02-01

    External contamination can cause false positive results in forensic hair testing for drugs of abuse and is therefore a major concern when hair evidence is used in court. Current literature about decontamination strategies is mainly focused on external cocaine contamination and no consensus on the best decontamination procedure for hair samples containing cannabinoids has been reached so far. In this study, different protocols with solvents, both organic as well as aqueous, were tested on blank and drug user hair for their performance on removing external cannabis contamination originating from either smoke or indirect contact with cannabis plant material. Smoke contamination was mimicked by exposing hair samples to smoke from a cannabis cigarette and indirect contact contamination by handling hair with cannabis contaminated gloves or hands. Δ9-tetrahydrocannabinol (THC) levels in the hair samples and wash solvents were determined using liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. Aqueous surfactant solutions removed more THC contamination compared to water, but much less than organic solvents. Methanol, dichloromethane and chloroform were most efficient in removing THC contamination. Due to its lower environmental impact, methanol was chosen as the preferred decontamination solvent. After testing of different sequential wash steps on externally contaminated blank hair, three protocols performed equally well, removing all normal level and more than 99% of unrealistically high levels of external cannabis contamination. Thorough testing on cannabis users' hair, both as such and after deliberate contamination, showed that using these protocols all contamination could be washed from the hair while no incorporated THC was removed from truly positive samples. The present study provides detailed scientific evidence in support of the recommendations of the Society of Hair Testing: a protocol using a single methanol wash followed by a single aqueous

  14. Practical Rate-Based Congestion Control for Wireless Mesh Networks

    Science.gov (United States)

    Elrakabawy, Sherif M.; Lindemann, Christoph

    We introduce an adaptive pacing scheme to overcome the drawbacks of TCP in wireless mesh networks with Internet connectivity. The pacing scheme is implemented at the wireless TCP sender as well as at the mesh gateway, and reacts according to the direction of TCP flows running across the wireless network and the Internet. TCP packets are transmitted rate-based within the TCP congestion window according to the current out-of-interference delay and the coefficient of variation of recently measured round-trip times. Opposed to the majority of previous work which builds on simulations, we implement a Linux prototype of our approach and evaluate its feasibility in a real 20-node mesh testbed. In an experimental performance study, we compare the goodput and fairness of our approach against the widely deployed TCP NewReno. Experiments show that our approach, which we denote as Mesh Adaptive Pacing (MAP), can achieve up to 150% more goodput than TCP NewReno and significantly improves fairness between competing flows. MAP is incrementally deployable since it is TCP-compatible, does not require cross-layer information from intermediate nodes along the path, and requires no modifications in the wired domain.

  15. Investigation on thiosulfate-involved organics and nitrogen removal by a sulfur cycle-based biological wastewater treatment process.

    Science.gov (United States)

    Qian, Jin; Lu, Hui; Cui, Yanxiang; Wei, Li; Liu, Rulong; Chen, Guang-Hao

    2015-02-01

    Thiosulfate, as an intermediate of biological sulfate/sulfite reduction, can significantly improve nitrogen removal potential in a biological sulfur cycle-based process, namely the Sulfate reduction-Autotrophic denitrification-Nitrification Integrated (SANI(®)) process. However, the related thiosulfate bio-activities coupled with organics and nitrogen removal in wastewater treatment lacked detailed examinations and reports. In this study, S2O3(2-) transformation during biological SO4(2-)/SO3(2-) co-reduction coupled with organics removal as well as S2O3(2-) oxidation coupled with chemolithotrophic denitrification were extensively evaluated under different experimental conditions. Thiosulfate is produced from the co-reduction of sulfate and sulfite through biological pathway at an optimum pH of 7.5 for organics removal. And the produced S2O3(2-) may disproportionate to sulfide and sulfate during both biological S2O3(2-) reduction and oxidation most possibly carried out by Desulfovibrio-like species. Dosing the same amount of nitrate, pH was found to be the more direct factor influencing the denitritation activity than free nitrous acid (FNA) and the optimal pH for denitratation (7.0) and denitritation (8.0) activities were different. Spiking organics significantly improved both denitratation and denitritation activities while minimizing sulfide inhibition of NO3(-) reduction during thiosulfate-based denitrification. These findings in this study can improve the understanding of mechanisms of thiosulfate on organics and nitrogen removal in biological sulfur cycle-based wastewater treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Hair removal.

    Science.gov (United States)

    Haedersdal, Merete; Haak, Christina S

    2011-01-01

    Hair removal with optical devices has become a popular mainstream treatment that today is considered the most efficient method for the reduction of unwanted hair. Photothermal destruction of hair follicles constitutes the fundamental concept of hair removal with red and near-infrared wavelengths suitable for targeting follicular and hair shaft melanin: normal mode ruby laser (694 nm), normal mode alexandrite laser (755 nm), pulsed diode lasers (800, 810 nm), long-pulse Nd:YAG laser (1,064 nm), and intense pulsed light (IPL) sources (590-1,200 nm). The ideal patient has thick dark terminal hair, white skin, and a normal hormonal status. Currently, no method of lifelong permanent hair eradication is available, and it is important that patients have realistic expectations. Substantial evidence has been found for short-term hair removal efficacy of up to 6 months after treatment with the available systems. Evidence has been found for long-term hair removal efficacy beyond 6 months after repetitive treatments with alexandrite, diode, and long-pulse Nd:YAG lasers, whereas the current long-term evidence is sparse for IPL devices. Treatment parameters must be adjusted to patient skin type and chromophore. Longer wavelengths and cooling are safer for patients with darker skin types. Hair removal with lasers and IPL sources are generally safe treatment procedures when performed by properly educated operators. However, safety issues must be addressed since burns and adverse events do occur. New treatment procedures are evolving. Consumer-based treatments with portable home devices are rapidly evolving, and presently include low-level diode lasers and IPL devices. Copyright © 2011 S. Karger AG, Basel.

  17. Site-based plaque removal efficacy of four branded toothbrushes and the effect of dental floss in interproximal plaque removal: a randomized examiner-blind controlled study.

    Science.gov (United States)

    Ashwath, Balachandran; Vijayalakshmi, Rajaraman; Arun, Dayanathi; Kumar, Vasanth

    2014-01-01

    The aim of this study was to evaluate the sitelevel plaque removal efficacy of four commercially available toothbrushes. The adjunctive benefit of dental floss on interproximal plaque removal was also evaluated. This study was designed as a randomized examiner- blinded clinical study involving 60 subjects. The subjects were randomly divided into four groups of 15 participants each, and a particular branded toothbrush was allotted for each group. Brushing technique, toothpaste, and brushing time were standardized for all the subjects. The Turesky- Gilmore-Glickman modification of Quigley-Hein plaque index was used to evaluate plaque scores at baseline, and 1, 2, 3, and 4 weeks by one blinded examiner. After 2 weeks, the subjects were provided with dental floss to be used in conjunction with the toothbrush. Buccal, lingual, and interproximal plaque reduction percentages were computed and analyzed for statistical significance. The four toothbrushes showed similar plaque removal scores at the three sites, with no statistical significance (P > .05). The interproximal plaque removal scores of the four toothbrushes were the least at 2 weeks (25%) when compared with buccal (65%) and lingual (60%) percentage scores. The addition of dental floss significantly increased the interproximal plaque removal scores, with 4-week scores revealing 70% removal. These data revealed the lack of significance between the four toothbrushes studied, which is in line with previous studies. The addition of dental floss had a significant effect on the interproximal plaque removal, which could be crucial in the maintenance of gingival health.

  18. Micropollutants removal from secondary-treated municipal wastewater using weak polyelectrolyte multilayer based nanofiltration membranes

    NARCIS (Netherlands)

    Abtahi, S. Mehran; Ilyas, Shazia; Joannis Cassan, Claire; Albasi, Claire; de Vos, Wiebe M.

    2018-01-01

    Nanofiltration (NF) is seen as a very promising technology to remove micropollutants (MPs) from wastewater. Unfortunately this process tends to produce a highly saline concentrate stream, as commercial NF membranes retain both the MPs and most of the ions. The high salinity makes subsequent

  19. Optimized biofilm-based systems for removal of pharmaceuticals from hospital waste water

    DEFF Research Database (Denmark)

    Andersen, Henrik R; Chhetri, Ravi; Hansen, Kamilla

    Discharge of hospital wastewater is of increasing concern, as hospitals are identified as chemical pollution source due to pharmaceutical content. This project seeks to develop the most efficient and economically feasible technology to remove pharmaceuticals from wastewater, regardless of the poi...

  20. Regenerating an Arsenic Removal Iron-Based Adsorptive Media System, Part 1: The Regeneration Process

    Science.gov (United States)

    Adsorptive media technology is a frequently used method of removing arsenic by small water systems because of its simplicity and efficiency. Current practice is to replace the media when it no longer reduces arsenic below the USEPA drinking water maximum contaminant level (MCL) ...

  1. Regenerating an Arsenic Removal Iron-Based Adsorptive Media System, Part 2: Performance and Cost

    Science.gov (United States)

    The replacement of exhausted, adsorptive media used to remove arsenic from drinking water accounts for approximately 80% of the total operational and maintenance (O/M) costs of this commonly used small system technology. The results of three, full scale system studies of an on-s...

  2. Pharmaceutical removal from water with iron- or manganese-based technologies

    NARCIS (Netherlands)

    Liu, Wenbo; Sutton, Nora B.; Rijnaarts, Huub H.M.; Langenhoff, Alette A.M.

    2016-01-01

    Pharmaceuticals are detected at trace levels in waters. Their adverse effects on aquatic ecosystems and human health demand novel pharmaceutical removal technologies for treating wastewater effluents. Iron (Fe) or manganese (Mn) may play important roles in these new technologies since these metals

  3. Effective removal of cationic dyes from aqueous solution using gum ghatti-based biodegradable hydrogel

    CSIR Research Space (South Africa)

    Mittal, H

    2015-08-01

    Full Text Available polymer was characterized by FTIR, SEM, and Brunauer–Emmett–Teller techniques. The Gg-cl-P(AAm-co-MAA) hydrogel was studied as an adsorbent for the removal of methylene blue (MB) and methyl violet (MV) from aqueous solutions. Adsorption of both the dyes...

  4. A novel enzyme-based acidizing system: Matrix acidizing and drilling fluid damage removal

    Energy Technology Data Exchange (ETDEWEB)

    Harris, R.E.; McKay, D.M. [Cleansorb Limited, Surrey (United Kingdom); Moses, V. [King`s College, London (United Kingdom)

    1995-12-31

    A novel acidizing process is used to increase the permeability of carbonate rock cores in the laboratory and to remove drilling fluid damage from cores and wafers. Field results show the benefits of the technology as applied both to injector and producer wells.

  5. Treatment outcomes with mandibular removable partial dentures: a population-based study of patient satisfaction.

    Science.gov (United States)

    Frank, R P; Milgrom, P; Leroux, B G; Hawkins, N R

    1998-07-01

    Little is known about the outcomes of treatment with mandibular removable partial dentures provided by dentists in private dental practice. This study examined 15 aspects of patient satisfaction and explored the factors found to be associated with dissatisfaction. A questionnaire was mailed to people whose dental insurance claims included CPT Code 5214 within the last 5 years. A composite measure of treatment outcome was created by combining the responses to the 15 satisfaction items, and 10 factors were then tested statistically to determine their relationship to dissatisfaction. A majority of the respondents were satisfied with the prosthesis, but a substantial amount of dissatisfaction existed. Dissatisfaction was greater when there was no previous wearing experience or when there was an opposing maxillary removable partial denture. Respondents under the age of 60 expressed more dissatisfaction than did those over the age of 60, and subjects with lower levels of general health also reported less satisfaction. One third of the respondents believed their prosthesis required adjustment or replacement, and one fourth said the removable partial denture had caused a problem with the natural teeth. A majority of survey respondents treated with a mandibular removable partial denture in private dental practice were satisfied with the prosthesis, but a substantial amount of dissatisfaction existed. Dissatisfaction was related to age, health, prior experience with a prosthesis, and the type of opposing dentition.

  6. CO2 removal from biogas with supported amine sorbents : First technical evaluation based on experimental data

    NARCIS (Netherlands)

    Sutanto, Stevia; Dijkstra, J. W.; Pieterse, J. A.Z.; Boon, J; Hauwert, P.; Brilman, D. W.F.

    2017-01-01

    Biogas from fermentation of manure and organic residues produces a gas stream that can be fed into the natural gas grid, provided impurities (CO2, H2S and H2O) are removed according to specifications prior to grid injection. Compared to conventional technologies, supported amine sorbents (SAS) seem

  7. Fly ash-based geopolymer for Pb removal from aqueous solution.

    Science.gov (United States)

    Al-Zboon, Kamel; Al-Harahsheh, Mohammad S; Hani, Falah Bani

    2011-04-15

    The aim of this work was to synthesis highly amorphous geopolymer from waste coal fly ash, to be used as an adsorbent for lead Pb(II) removal from aqueous wastewater. The effect of various parameters including geopolymer dosage, initial concentration, contact time, pH and temperature on lead adsorption were investigated. The major components of the used ash in the current study were SiO(2), Al(2)O(3) and Fe(2)O(3) representing 91.53 wt% of its mass. It was found that the synthesized geopolymer has higher removal capacity for lead ions when compared with that of raw coal fly ash. The removal efficiency increases with increasing geopolymer dosage, contact time, temperature, and the decrease of Pb(2+) initial concentration. The optimum removal efficiency was obtained at pH 5. Adsorption isotherm study indicated that Langmuir isotherm model is the best fit for the experimental data than Freundlich model. It was found also that the adsorption process is endothermic and more favorable at higher temperatures. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Nitrogen availability influences phosphorus removal in microalgae-based wastewater treatment.

    Science.gov (United States)

    Beuckels, Annelies; Smolders, Erik; Muylaert, Koenraad

    2015-06-15

    Microalgae offer a promising technology to remove and re-use the nutrients N and P from wastewater. For effective removal of both N and P, it is important that microalgae can adjust the N and P concentration in their biomass to the N and P supply in the wastewater. The aim of this study was to evaluate to what extent microalgae can adjust the N and P concentrations in their biomass to the N and P supply in the wastewater, and to what extent supply of one nutrient influences the removal of the other nutrient. Using Chlorella and Scenedesmus as model organisms, we quantified growth and biomass composition in medium with different initial N and P concentrations in all possible combinations. Nutrient supply marginally affected biomass yield of both microalgae but had a strong influence on the composition of the biomass. The nutrient concentrations in the biomass ranged 5.0-10.1 % for N and 0.5-1.3 % for P in Chlorella and 2.9-8.4 % for N and 0.5-1.7 % for P in Scenedesmus. The concentrations of P in the biomass remained low and were relatively constant (0.6-0.8 % P) when the N concentration in the biomass was low. As a result, removal of P from the wastewater was influenced by the concentration of N in the wastewater. When the initial N concentration in the wastewater was above 40 mg L(-1) the microalgae could remove up to 6 mg P L(-1), but this removal was only 2 mg P L(-1) when the initial N concentration was below 20 mg L(-1). A lower N supply increased the carbohydrate concentration to about 40% and lipid concentration to about 30% for both species, compared to around 15% and 10% respectively at high N supply. Our results show that sufficiently high N concentrations are needed to ensure effective P removal from wastewater due to the positive effect of N on the accumulation of P. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Paint removal activities in Canada

    Science.gov (United States)

    Foster, Terry

    1993-03-01

    Paint removal activities currently under way in Canada include: research and development of laser paint stripping; development and commercialization of a new blasting medium based on wheat starch; commercialization of a new blasting medium and process using crystalline ice blasting for paint removal and surface cleaning; and the development of automated and robotic systems for paint stripping applications. A specification for plastic media blasting (PMB) of aircraft and aircraft components is currently being drafted by NDHQ for use by the Canadian Armed Forces (CAF) and contractors involved in coating removal for the CAF. Defense Research Establishment Pacific (DREP) is studying the effects of various blast media on coating removal rates, and minimizing the possibility of damage to substrates other than aluminum such as graphite epoxy composite and Kevlar. The effects of plastic media blasting on liquid penetrant detection of fatigue cracks is also under investigation.

  10. Preparation of geopolymer-based inorganic membrane for removing Ni{sup 2+} from wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Yuanyuan; Yuan, Yuan; Wang, Kaituo; He, Yan; Cui, Xuemin, E-mail: cui-xm@tsinghua.edu.cn

    2015-12-15

    Highlights: • A type free-sintering geopolymer membrane for waste water treatment was fabricated. • The geopolymer inorganic membrane held good strength and appropriate water flux. • The mechanism of removing Ni{sup 2+} combined actions of the adsorption and rejection. • The geopolymer membrane is a promising way to remove heavy metal ions in industry. - Abstract: A type of novel free-sintering and self-supporting inorganic membrane for wastewater treatment was fabricated in this study. This inorganic membrane was synthesised using metakaolin and sodium silicate solutions moulded according to a designed molar ratio (SiO{sub 2}/Al{sub 2}O{sub 3} = 2.96, Na{sub 2}O/Al{sub 2}O{sub 3} = 0.8 and H{sub 2}O/Na{sub 2}O = 19) which formed a homogenous structure and had a relative concentration pore size distribution, via scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) analyses. In this work, the Ni{sup 2+} removal effect of geopolymer inorganic membrane was studied under different pH value, initial concentration of Ni{sup 2+} solutions and initial operation temperature. Results showed that geopolymer inorganic membrane efficiently removes Ni{sup 2+} from wastewater because of the combined actions of the adsorption and rejection of this membrane on Ni{sup 2+} during membrane separation. Therefore, geopolymer inorganic membrane may have positive potential applications in removing Ni{sup 2+} or other heavy metal ions from aqueous industrial wastewater.

  11. Using environmental chemistry technologies for the removal of arsenic from drinking water, and fat and oil based phase change materials for thermal energy storage

    Science.gov (United States)

    Sutterlin, William R.

    The first four chapters of this dissertation involve the removal of arsenic from drinking water. Various forms of a macroporous char prepared by partial gasification of subbituminous coal were studied for removal of arsenic(V) and arsenic(III) from water. In increasing order of effectiveness for arsenic(V) removal were untreated char removed arsenic(V) and arsenic(III) from 10,000 mL of water containing 500 micrograms/L of arsenic to levels below 10 micrograms/L. The capacity of the solid to remove arsenic was significantly diminished in water containing 4 mg/L of phosphate. An electrical current passed over 4 g of iron(III) oxide char in a column enabled removal of arsenic(III) from 14,000 mL of 500 micrograms/L arsenic(III) to below 10 micrograms/liter and at significantly higher flow rates than could be employed without electrolysis. The fifth chapter in this dissertation focused on the retention of organics onto a char/concrete pellet. A mixture of naphthalene, pentachlorophenol, biphenyl, toluene, tetrachloroethane, and chlorobenzene were impregnated into a loose granular char, a char/concrete pellet and a sand/concrete pellet. The results showed that the char/concrete pellet had significant advantages over the other forms. Chapters 6--9 focus on phase change materials (PCMs). These PCMs are made from fats and oils. PCMs are perhaps the only proven method that can provide near 100% thermal energy storage. In chapter 7 a novel HPLC method was developed that could provide quantification and qualification of the resulting products formed after PCM synthesis. In chapter 8 thermal cycling studies were conducted on the fat and oil based PCMs. These thermal cycle demonstrated that these PCMs were capable of going through a multitude of freeze and melt processes with little to no degradation if the appropriate preservative is used. Finally in chapter 9 the PCM is incorporated into a simulated 100 th scale house. A traditional freon based evaporator is used to freeze

  12. FMO-based H.264 frame layer rate control for low bit rate video transmission

    Science.gov (United States)

    Cajote, Rhandley D.; Aramvith, Supavadee; Miyanaga, Yoshikazu

    2011-12-01

    The use of flexible macroblock ordering (FMO) in H.264/AVC improves error resiliency at the expense of reduced coding efficiency with added overhead bits for slice headers and signalling. The trade-off is most severe at low bit rates, where header bits occupy a significant portion of the total bit budget. To better manage the rate and improve coding efficiency, we propose enhancements to the H.264/AVC frame layer rate control, which take into consideration the effects of using FMO for video transmission. In this article, we propose a new header bits model, an enhanced frame complexity measure, a bit allocation and a quantization parameter adjustment scheme. Simulation results show that the proposed improvements achieve better visual quality compared with the JM 9.2 frame layer rate control with FMO enabled using a different number of slice groups. Using FMO as an error resilient tool with better rate management is suitable in applications that have limited bandwidth and in error prone environments such as video transmission for mobile terminals.

  13. FMO-based H.264 frame layer rate control for low bit rate video transmission

    Directory of Open Access Journals (Sweden)

    Miyanaga Yoshikazu

    2011-01-01

    Full Text Available Abstract The use of flexible macroblock ordering (FMO in H.264/AVC improves error resiliency at the expense of reduced coding efficiency with added overhead bits for slice headers and signalling. The trade-off is most severe at low bit rates, where header bits occupy a significant portion of the total bit budget. To better manage the rate and improve coding efficiency, we propose enhancements to the H.264/AVC frame layer rate control, which take into consideration the effects of using FMO for video transmission. In this article, we propose a new header bits model, an enhanced frame complexity measure, a bit allocation and a quantization parameter adjustment scheme. Simulation results show that the proposed improvements achieve better visual quality compared with the JM 9.2 frame layer rate control with FMO enabled using a different number of slice groups. Using FMO as an error resilient tool with better rate management is suitable in applications that have limited bandwidth and in error prone environments such as video transmission for mobile terminals.

  14. Estimating mental fatigue based on electroencephalogram and heart rate variability

    Science.gov (United States)

    Zhang, Chong; Yu, Xiaolin

    2010-01-01

    The effects of long term mental arithmetic task on psychology are investigated by subjective self-reporting measures and action performance test. Based on electroencephalogram (EEG) and heart rate variability (HRV), the impacts of prolonged cognitive activity on central nervous system and autonomic nervous system are observed and analyzed. Wavelet packet parameters of EEG and power spectral indices of HRV are combined to estimate the change of mental fatigue. Then wavelet packet parameters of EEG which change significantly are extracted as the features of brain activity in different mental fatigue state, support vector machine (SVM) algorithm is applied to differentiate two mental fatigue states. The experimental results show that long term mental arithmetic task induces the mental fatigue. The wavelet packet parameters of EEG and power spectral indices of HRV are strongly correlated with mental fatigue. The predominant activity of autonomic nervous system of subjects turns to the sympathetic activity from parasympathetic activity after the task. Moreover, the slow waves of EEG increase, the fast waves of EEG and the degree of disorder of brain decrease compared with the pre-task. The SVM algorithm can effectively differentiate two mental fatigue states, which achieves the maximum classification accuracy (91%). The SVM algorithm could be a promising tool for the evaluation of mental fatigue. Fatigue, especially mental fatigue, is a common phenomenon in modern life, is a persistent occupational hazard for professional. Mental fatigue is usually accompanied with a sense of weariness, reduced alertness, and reduced mental performance, which would lead the accidents in life, decrease productivity in workplace and harm the health. Therefore, the evaluation of mental fatigue is important for the occupational risk protection, productivity, and occupational health.

  15. Estimating time-based instantaneous total mortality rate based on the age-structured abundance index

    Science.gov (United States)

    Wang, Yingbin; Jiao, Yan

    2015-05-01

    The instantaneous total mortality rate ( Z) of a fish population is one of the important parameters in fisheries stock assessment. The estimation of Z is crucial to fish population dynamics analysis, abundance and catch forecast, and fisheries management. A catch curve-based method for estimating time-based Z and its change trend from catch per unit effort (CPUE) data of multiple cohorts is developed. Unlike the traditional catch-curve method, the method developed here does not need the assumption of constant Z throughout the time, but the Z values in n continuous years are assumed constant, and then the Z values in different n continuous years are estimated using the age-based CPUE data within these years. The results of the simulation analyses show that the trends of the estimated time-based Z are consistent with the trends of the true Z, and the estimated rates of change from this approach are close to the true change rates (the relative differences between the change rates of the estimated Z and the true Z are smaller than 10%). Variations of both Z and recruitment can affect the estimates of Z value and the trend of Z. The most appropriate value of n can be different given the effects of different factors. Therefore, the appropriate value of n for different fisheries should be determined through a simulation analysis as we demonstrated in this study. Further analyses suggested that selectivity and age estimation are also two factors that can affect the estimated Z values if there is error in either of them, but the estimated change rates of Z are still close to the true change rates. We also applied this approach to the Atlantic cod ( Gadus morhua) fishery of eastern Newfoundland and Labrador from 1983 to 1997, and obtained reasonable estimates of time-based Z.

  16. Observable Social Cognition--A Rating Scale: an interview-based assessment for schizophrenia.

    Science.gov (United States)

    Healey, Kristin M; Combs, Dennis R; Gibson, Clare M; Keefe, Richard S E; Roberts, David L; Penn, David L

    2015-01-01

    Individuals with schizophrenia consistently show impairments in social cognition (SC). SC has become a potential treatment target due to its association with functional outcomes. An alternative method of assessment is to administer an observer-based scale incorporating an informant's "first hand" impressions in ratings. The present study used the Observable Social Cognition: A Rating Scale (OSCARS) in 62 outpatients and 50 non-psychiatric controls (NPCs) to assess performance in domains of SC (e.g. emotion perception, theory of mind). The OSCARS demonstrated sufficient internal consistency and test-retest reliability. Construct validity was assessed through an exploratory factor analysis. Patient OSCARS indices were not significantly correlated with measures of SC with the exception of aggressive attributional style. Individuals with less impairment in SC reacted more aggressively to ambiguous situations. NPC OSCARS were significantly correlated with measures of theory of mind and attributional style. In a combined sample of patients and controls, six of eight items were significantly correlated with the SC task assessing the same domain, providing modest evidence of convergent validity. In patients, the OSCARS was significantly correlated with measures of functional outcome and neurocognition. Last, the OSCARS was found to be significantly associated with functional outcome after the influence of objective measures of SC was statistically removed. The present study provides preliminary evidence that the OSCARS may be useful for clinicians in collecting data about patients' potential real-world SC deficits, in turn increasing the degree to which these impairments may be targeted in treatment.

  17. Long-term observations of black carbon mass concentrations at Fukue Island, western Japan, during 2009-2015: constraining wet removal rates and emission strengths from East Asia

    Science.gov (United States)

    Kanaya, Yugo; Pan, Xiaole; Miyakawa, Takuma; Komazaki, Yuichi; Taketani, Fumikazu; Uno, Itsushi; Kondo, Yutaka

    2016-08-01

    Long-term (2009-2015) observations of atmospheric black carbon (BC) mass concentrations were performed using a continuous soot-monitoring system (COSMOS) at Fukue Island, western Japan, to provide information on wet removal rate constraints and the emission strengths of important source regions in East Asia (China and others). The annual average mass concentration was 0.36 µg m-3, with distinct seasonality; high concentrations were recorded during autumn, winter, and spring and were caused by Asian continental outflows, which reached Fukue Island in 6-46 h. The observed data were categorized into two classes, i.e., with and without a wet removal effect, using the accumulated precipitation along a backward trajectory (APT) for the last 3 days as an index. Statistical analysis of the observed ΔBC / ΔCO ratios was performed to obtain information on the emission ratios (from data with zero APT only) and wet removal rates (including data with nonzero APTs). The estimated emission ratios (5.2-6.9 ng m-3 ppb-1) varied over the six air mass origin areas; the higher ratios for south-central East China (30-35° N) than for north-central East China (35-40° N) indicated the relative importance of domestic emissions and/or biomass burning sectors. The significantly higher BC / CO emission ratios adopted in the bottom-up Regional Emission inventory in Asia (REAS) version 2 (8.3-23 ng m-3 ppb-1) over central East China and Korea needed to be reduced at least by factors of 1.3 and 2.8 for central East China and Korea, respectively, but the ratio for Japan was reasonable. The wintertime enhancement of the BC emission from China, predicted by REAS2, was verified for air masses from south-central East China but not for those from north-central East China. Wet removal of BC was clearly identified as a decrease in the ΔBC / ΔCO ratio against APT. The transport efficiency (TE), defined as the ratio of the ΔBC / ΔCO ratio with precipitation to that without precipitation, was

  18. A novel method to remove GPR background noise based on the similarity of non-neighboring regions

    Science.gov (United States)

    Montiel-Zafra, V.; Canadas-Quesada, F. J.; Vera-Candeas, P.; Ruiz-Reyes, N.; Rey, J.; Martinez, J.

    2017-09-01

    Ground penetrating radar (GPR) is a non-destructive technique that has been widely used in many areas of research, such as landmine detection or subsurface anomalies, where it is required to locate targets embedded within a background medium. One of the major challenges in the research of GPR data remains the improvement of the image quality of stone materials by means of detection of true anisotropies since most of the errors are caused by an incorrect interpretation by the users. However, it is complicated due to the interference of the horizontal background noise, e.g., the air-ground interface, that reduces the high-resolution quality of radargrams. Thus, weak or deep anisotropies are often masked by this type of noise. In order to remove the background noise obtained by GPR, this work proposes a novel background removal method assuming that the horizontal noise shows repetitive two-dimensional regions along the movement of the GPR antenna. Specifically, the proposed method, based on the non-local similarity of regions over the distance, computes similarities between different regions of the same depth in order to identify most repetitive regions using a criterion to avoid closer regions. Evaluations are performed using a set of synthetic and real GPR data. Experimental results show that the proposed method obtains promising results compared to the classic background removal techniques and the most recently published background removal methods.

  19. Mesostructured metal oxide-based nanocomposites as sorbents for H2S removal from syngas coal gasification

    OpenAIRE

    Mureddu, Mauro

    2015-01-01

    Desulphurization of gas phase sulphur compounds has been receiving dramatic attention since hazardous, corrosive, and toxic gases that cause environmental damages (especially acid rain) and industrial challenges (i.e., corrosion of equipment and deactivation of catalysts). This dissertation presents results of R&D efforts to develop efficient MeOx/SBA-15-based sorbents for H2S removal in view of possible applications in hydrogen purification, air pollution control, and deep des...

  20. Revisiting the influence of loading on organic material removal in primary facultative ponds

    Directory of Open Access Journals (Sweden)

    F. J. A. da Silva

    2010-03-01

    Full Text Available This paper investigated the influence of organic loading on BOD and COD removal in primary facultative ponds. The study was based on six full-scale pond plants in which average removals of unfiltered biochemical oxygen demand (BOD and chemical oxygen demand (COD were 72 and 50%, respectively. For filtered samples, the removals were 89 and 83%, respectively. First-order removal rates assuming ideal hydraulic patterns (completely mixed and plug-flow decreased with increments in the mean hydraulic retention time (HRT. Reduction in organic loading also caused a decrease in removal rates. The results emphasized that HRT and surface organic loading are more reliable to estimate first-order removal rates than traditional Arrhenius-style equations. Thus, HRT and surface organic loading can be used to compute more realistic first-order removal rates and surface removal rates. An alternative design procedure based on HRT and surface organic loading was proposed and demonstrated.

  1. Multi-criteria assessment of community-based fluoride-removal technologies for rural Ethiopia.

    Science.gov (United States)

    Osterwalder, Lars; Johnson, C Annette; Yang, Hong; Johnston, Richard B

    2014-08-01

    Elevated concentrations of naturally-occurring fluoride in groundwater pose a serious health risk to millions of people living in the Ethiopian Rift Valley. In the absence of low-fluoride water resources of sufficient capacity, fluoride removal from drinking water is the accepted mitigation option. To date, five different community-level fluoride-removal technologies have been implemented in Ethiopia, although only a few units have been found in a functional state in the field. Which technology should be promoted and up-scaled is the subject of controversial debate amongst key stakeholders. This paper describes a multi-criteria decision analysis exercise, which was conducted with the participation of stakeholders in Ethiopia during a one-day workshop, to assess in an objective and transparent manner the available technology options. Criteria for technology comparison were selected and weighted, thus enabling the participants to assess the advantages and disadvantages of the different technologies and hear the views of other stakeholders. It was shown that there is no single most-preferable, technical solution for fluoride removal in Ethiopia. Selection of the most suitable solution depends on location-specific parameters and on the relative importance given to different criteria by the stakeholders involved. The data presented in this paper can be used as reference values for Ethiopia. © 2013. Published by Elsevier B.V. All rights reserved.

  2. Experiment and DFT studies on radioiodine removal and storage mechanism by imidazolium-based ionic liquid.

    Science.gov (United States)

    Cao, Bobo; Liu, Shuangyue; Du, Dongmei; Xue, Zhimin; Fu, Hui; Sun, Haitao

    2016-03-01

    In order to remove and store radioactive substances effectively, studies on the mechanisms of radioiodine captured by ionic liquids (ILs) with a fixed cation (1-butyl-3-methyl-imidazolium cation [Bmim]+) were carried out in experimental and theoretical methods. Fourier transform infrared attenuated total reflectance (FT-IR ATR) spectra of 2BP8HQ and ultraviolet-visible (UV/vis) spectroscopy were used to investigate the kinetic process of radioiodine removal by ILs in experiment. Corresponding theoretical investigations on the structures and formation mechanisms of ILs, bare anions and complexes as well as hydrogen bonds was carried using density functional theory. The electrostatic potential was used in configuration design and construction. Charge distribution was used to show the variation of atom charge density, Interaction energy and vibration frequency change were performed to explore possible mechanisms on the halogen bond formation between radioiodine molecule and bare anion or anion in ILs when radioiodine captured by ILs. In order to characterize halogen bonds both natural bond orbital analysis and atoms in molecules analysis were performed. Both experimental and computational results showed that radioiodine could be captured by ILs with a 1:1mol stoichiometry. It was noteworthy that [Bmim][Br], [Bmim][I] and [Bmim][Cl], containing high radioiodine capture efficiency anions, were better candidates in removal and reliable storage of radioiodine for their capture efficiencies of over 80% in 5h. Copyright © 2016. Published by Elsevier Inc.

  3. Biological removal of gaseous ammonia in biofilters: space travel and earth-based applications

    Science.gov (United States)

    Joshi, J. A.; Hogan, J. A.; Cowan, R. M.; Strom, P. F.; Finstein, M. S.; Janes, H. W. (Principal Investigator)

    2000-01-01

    Gaseous NH3 removal was studied in laboratory-scale biofilters (14-L reactor volume) containing perlite inoculated with a nitrifying enrichment culture. These biofilters received 6 L/min of airflow with inlet NH3 concentrations of 20 or 50 ppm, and removed more than 99.99% of the NH3 for the period of operation (101, 102 days). Comparison between an active reactor and an autoclaved control indicated that NH3 removal resulted from nitrification directly, as well as from enhanced absorption resulting from acidity produced by nitrification. Spatial distribution studies (20 ppm only) after 8 days of operation showed that nearly 95% of the NH3 could be accounted for in the lower 25% of the biofilter matrix, proximate to the port of entry. Periodic analysis of the biofilter material (20 and 50 ppm) showed accumulation of the nitrification product NO3- early in the operation, but later both NO2- and NO3- accumulated. Additionally, the N-mass balance accountability dropped from near 100% early in the experiments to approximately 95 and 75% for the 20- and 50-ppm biofilters, respectively. A partial contributing factor to this drop in mass balance accountability was the production of NO and N2O, which were detected in the biofilter exhaust.

  4. Preparation of geopolymer-based inorganic membrane for removing Ni(2+) from wastewater.

    Science.gov (United States)

    Ge, Yuanyuan; Yuan, Yuan; Wang, Kaituo; He, Yan; Cui, Xuemin

    2015-12-15

    A type of novel free-sintering and self-supporting inorganic membrane for wastewater treatment was fabricated in this study. This inorganic membrane was synthesised using metakaolin and sodium silicate solutions moulded according to a designed molar ratio (SiO2/Al2O3=2.96, Na2O/Al2O3=0.8 and H2O/Na2O=19) which formed a homogenous structure and had a relative concentration pore size distribution, via scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analyses. In this work, the Ni(2+) removal effect of geopolymer inorganic membrane was studied under different pH value, initial concentration of Ni(2+) solutions and initial operation temperature. Results showed that geopolymer inorganic membrane efficiently removes Ni(2+) from wastewater because of the combined actions of the adsorption and rejection of this membrane on Ni(2+) during membrane separation. Therefore, geopolymer inorganic membrane may have positive potential applications in removing Ni(2+) or other heavy metal ions from aqueous industrial wastewater. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Subspace-based interference removal methods for a multichannel biomagnetic sensor array

    Science.gov (United States)

    Sekihara, Kensuke; Nagarajan, Srikantan S.

    2017-10-01

    Objective. In biomagnetic signal processing, the theory of the signal subspace has been applied to removing interfering magnetic fields, and a representative algorithm is the signal space projection algorithm, in which the signal/interference subspace is defined in the spatial domain as the span of signal/interference-source lead field vectors. This paper extends the notion of this conventional (spatial domain) signal subspace by introducing a new definition of signal subspace in the time domain. Approach. It defines the time-domain signal subspace as the span of row vectors that contain the source time course values. This definition leads to symmetric relationships between the time-domain and the conventional (spatial-domain) signal subspaces. As a review, this article shows that the notion of the time-domain signal subspace provides useful insights over existing interference removal methods from a unified perspective. Main results and significance. Using the time-domain signal subspace, it is possible to interpret a number of interference removal methods as the time domain signal space projection. Such methods include adaptive noise canceling, sensor noise suppression, the common temporal subspace projection, the spatio-temporal signal space separation, and the recently-proposed dual signal subspace projection. Our analysis using the notion of the time domain signal space projection reveals implicit assumptions these methods rely on, and shows that the difference between these methods results only from the manner of deriving the interference subspace. Numerical examples that illustrate the results of our arguments are provided.

  6. Nature-based solutions for hydro-meteorological risk reduction and nutrient removal in the Nordic and Arctic regions

    Science.gov (United States)

    Bring, Arvid; Kalantari, Zahra

    2017-04-01

    Natural ecological functions provide essential and fundamental benefits to mankind, but can also be actively employed in nature-based solutions to specific challenges in society. For example, water-related ecosystem services have a role in such societal benefits as flood protection, erosion control, and excess nutrient removal. Ecosystem services may be produced and consumed in different locations, and research has recently attempted to formalize this discrepancy in identifying service providing areas (SPAs), service benefitting areas (SBAs), and service connecting areas (SCAs). However, in terms of water-related services, there is a lack of formal evaluation of how SPAs, SBAs, and SCAs are related to hydrological measures such as discharge, flood recurrence, excess nutrient removal, etc. We seek to map SPAs, SBAs and SCAs for a number of key ecosystem services in the Nordic and Arctic region though established ecological definitions (typically, based on land use) and evaluate the findings alongside metrics of hydrological connectivity (river networks), provisioning areas (runoff generating areas), and benefitting areas (river stretches where water flow is moderated). We make use of extensive GIS analysis using both high-resolution land cover data and river network maps. In the end, the results are expected to contribute to identifying how water-related ecosystem services can be employed as nature-based solutions for hydro-meteorological risk reduction and nutrient removal in a changing climate in the Nordic and Arctic regions.

  7. Evaluation of two lead-based paint removal and waste stabilization technology combinations on typical exterior surfaces.

    Science.gov (United States)

    Daniels, A E; Kominsky, J R; Clark, P J

    2001-10-12

    A study was conducted to demonstrate the effectiveness of a wet abrasive blasting technology to remove lead-based paint from exterior wood siding and brick substrates as well as to evaluate the effectiveness of two waste stabilization technologies to stabilize the resulting blast media (coal slag and mineral sand) paint debris thereby reducing the leachable lead content. The lead-based paint removal technology effectiveness was determined by the use of an X-ray fluorescence (XRF) spectrum analyzer (L- and K-shell). The effectiveness of the technologies to stabilize the debris was evaluated through the toxicity characteristic leaching procedure (TCLP). Wet abrasive blasting effectively removed the lead-based paint coating from both the wood and brick substrates to below the US Department of Housing and Urban Development Guideline (1mg/cm(2)) with no minimal or no damage to the underlying substrates (Pstabilization technologies consistently stabilized the resultant paint debris to achieve a leachable lead content below the RCRA regulatory threshold of <5 mg/l.

  8. MEASURING THE ELASTICITY OF THE LOCAL TELECOMMUNICATIONS TAX BASE WITH RESPECT TO THE TAX RATE

    National Research Council Canada - National Science Library

    Yonghong Wu; David Merriman

    2009-01-01

    .... They estimate the tax rate elasticity of the telecommunications tax base after instrumenting for own telecommunications tax rate. The statistical results suggest that the consumption of telecommunication services is initially fairly unresponsive to tax rate differentials.

  9. Chromium(VI Removal from Aqueous Solution by Magnetite Coated by a Polymeric Ionic Liquid-Based Adsorbent

    Directory of Open Access Journals (Sweden)

    Thania Alexandra Ferreira

    2017-05-01

    Full Text Available An evaluation of the chromium(VI adsorption capacity of four magnetite sorbents coated with a polymer phase containing polymethacrylic acid or polyallyl-3-methylimidazolium is presented. Factors that influence the chromium(VI removal such as solution pH and contact time were investigated in batch experiments and in stirred tank reactor mode. Affinity and rate constants increased with the molar ratio of the imidazolium. The highest adsorption was obtained at pH 2.0 due to the contribution of electrostatic interactions.

  10. Influence of removing excess of resin-based materials applied to eroded enamel on the resistance to erosive challenge.

    Science.gov (United States)

    Tereza, Guida Paola Genovez; de Oliveira, Gabriela Cristina; de Andrade Moreira Machado, Maria Aparecida; de Oliveira, Thais Marchine; da Silva, Thiago Cruvinel; Rios, Daniela

    2016-04-01

    The aim of this study was to evaluate the effect of removing excess of resin-based materials applied to eroded enamel, subjected to erosive challenge. Bovine enamel blocks were immersed in HCl 0.01M, pH 2.3, for 30s under agitation at 50 rpm in room temperature, in order to form a softened erosion lesion. The blocks were then randomly divided into eight groups (n=12) and treated as follows: Cn- and Ce-control without treatment, Hn- and He-fissure resin sealant (Helioseal Clear(®)), An- and Ae-self-etch adhesive (Adhese(®)), In- and Ie-infiltrant (Icon(®)); being n-with excess removal and e-without excess removal of the material. After application of the materials, the blocks were immersed in HCl for 2 min, followed by immersion in artificial saliva for 120 min. This cycle was repeated four times a day for five days. Material thickness and enamel wear were assessed using profilometry. Data were analyzed by two-way ANOVA and Tukey's test (Pmaterial over enamel, being similar effective in inhibiting erosion progression (P>0.05). Groups Hn, An, and In (with excess removal) were similar to controls (Cn, Ce) and resulted in near enamel loss after application and after erosive challenge (P>0.05). Resin-based materials are able to protect enamel against erosion only when they are present over enamel, as a physical barrier. The resin-based materials demonstrated potential to prevent the progression of erosion lesions when the material remains on the dental surface. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Improved virus removal by high-basicity polyaluminum coagulants compared to commercially available aluminum-based coagulants.

    Science.gov (United States)

    Shirasaki, N; Matsushita, T; Matsui, Y; Oshiba, A; Marubayashi, T; Sato, S

    2014-01-01

    We investigated the effects of basicity, sulfate content, and aluminum hydrolyte species on the ability of polyaluminum chloride (PACl) coagulants to remove F-specific RNA bacteriophages from river water at a pH range of 6-8. An increase in PACl basicity from 1.5 to 2.1 and the absence of sulfate led to a reduction of the amount of monomeric aluminum species (i.e., an increase of the total amount of polymeric aluminum and colloidal aluminum species) in the PACl, to an increase in the colloid charge density of the PACl, or to both and, as a result, to high virus removal efficiency. The efficiency of virus removal at around pH 8 observed with PACl-2.1c, a nonsulfated high-basicity PACl (basicity 2.1-2.2) with a high colloidal aluminum content, was larger than that observed with PACl-2.1b, a nonsulfated high-basicity PACl (basicity 2.1-2.2) with a high polymeric aluminum content. In contrast, although extremely high basicity PACls (e.g., PACl-2.7ns, basicity 2.7) effectively removed turbidity and UV260-absorbing natural organic matter and resulted in a very low residual aluminum concentration, the virus removal ratio with PACl-2.7ns was smaller than the ratio with PACl-2.1c at around pH 8, possibly as a result of a reduction of the colloid charge density of the PACl as the basicity was increased from 2.1 to 2.7. Liquid (27)Al NMR analysis revealed that PACl-2.1c contained Al30 species, which was not the case for PACl-2.1b or PACl-2.7ns. This result suggests that Al30 species probably played a major role in virus removal during the coagulation process. In summary, PACl-2.1c, which has high colloidal aluminum content, contains Al30 species, and has a high colloid charge density, removed viruses more efficiently (>4 log10 for infectious viruses) than the other aluminum-based coagulants-including commercially available PACls (basicity 1.5-1.8), alum, and PACl-2.7ns-over the entire tested pH (6-8) and coagulant dosage (0.54-5.4 mg-Al/L) ranges. Copyright © 2013 Elsevier

  12. Impact of Cr(VI) on P removal performance in enhanced biological phosphorus removal (EBPR) system based on the anaerobic and aerobic metabolism.

    Science.gov (United States)

    Fang, Jing; Sun, Pei-de; Xu, Shao-juan; Luo, Tao; Lou, Ju-qing; Han, Jing-yi; Song, Ying-qi

    2012-10-01

    Influence of Cr(VI) on P removal in enhanced biological phosphorus removal (EBPR) system was investigated with respect to the composition of poly-phosphate-accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), the transformation of poly-β-hydroxyalkanoates (PHA) and glycogen, enzymes' activities, and the intracellular Cr. Whether EBPR system could revive after Cr(VI) shock was also explored. Results showed P removal performance was completely inhibited by Cr(VI) with the concentration more than 5 mg L(-1). PAOs were more sensitive to Cr(VI) than GAOs and the other bacteria were. PHA consumption, glycogen synthesis and adenylate kinase's activity had been inhibited by 5 mg L(-1) Cr(VI). Both adenylate kinase's activity and P removal efficiency were negatively correlated with the intracellular Cr. Recovery experiments revealed that P removal performance with 5 mg L(-1) Cr(VI) shock could revive after a 2-day recovery treatment, while systems with high level Cr(VI) (20 and 60 mg L(-1)) shock could not. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. 3D graphene-based nanostructured materials as sorbents for cleaning oil spills and for the removal of dyes and miscellaneous pollutants present in water.

    Science.gov (United States)

    Riaz, Muhammad Adil; McKay, Gordon; Saleem, Junaid

    2017-12-01

    Oil spills over seawater and dye pollutants in water cause economic and environmental damage every year. Among various methods to deal oil spill problems, the use of porous materials has been proven as an effective strategy. In recent years, graphene-based porous sorbents have been synthesized to address the shortcomings associated with conventional sorbents such as their low uptake capacity, slow sorption rate, and non-recyclability. This article reviews the research undertaken to control oil spillage using three-dimensional (3D) graphene-based materials. The use of these materials for removal of dyes and miscellaneous environmental pollutants from water is explored and the application of various multifunctional 3D oil sorbents synthesized by surface modification technique is presented. The future prospects and limitations of these materials as sorbents are also discussed.

  14. Radiocarbon Based Ages and Growth Rates: Hawaiian Deep Sea Corals

    Energy Technology Data Exchange (ETDEWEB)

    Roark, E B; Guilderson, T P; Dunbar, R B; Ingram, B L

    2006-01-13

    The radial growth rates and ages of three different groups of Hawaiian deep-sea 'corals' were determined using radiocarbon measurements. Specimens of Corallium secundum, Gerardia sp., and Leiopathes glaberrima, were collected from 450 {+-} 40 m at the Makapuu deep-sea coral bed using a submersible (PISCES V). Specimens of Antipathes dichotoma were collected at 50 m off Lahaina, Maui. The primary source of carbon to the calcitic C. secundum skeleton is in situ dissolved inorganic carbon (DIC). Using bomb {sup 14}C time markers we calculate radial growth rates of {approx} 170 {micro}m y{sup -1} and ages of 68-75 years on specimens as tall as 28 cm of C. secundum. Gerardia sp., A. dichotoma, and L. glaberrima have proteinaceous skeletons and labile particulate organic carbon (POC) is their primary source of architectural carbon. Using {sup 14}C we calculate a radial growth rate of 15 {micro}m y{sup -1} and an age of 807 {+-} 30 years for a live collected Gerardia sp., showing that these organisms are extremely long lived. Inner and outer {sup 14}C measurements on four sub-fossil Gerardia spp. samples produce similar growth rate estimates (range 14-45 {micro}m y{sup -1}) and ages (range 450-2742 years) as observed for the live collected sample. Similarly, with a growth rate of < 10 {micro}m y{sup -1} and an age of {approx}2377 years, L. glaberrima at the Makapuu coral bed, is also extremely long lived. In contrast, the shallow-collected A. dichotoma samples yield growth rates ranging from 130 to 1,140 {micro}m y{sup -1}. These results show that Hawaiian deep-sea corals grow more slowly and are older than previously thought.

  15. 75 FR 53688 - Constellation Mystic Power, LLC; Supplemental Notice That Initial Market-Based Rate Filing...

    Science.gov (United States)

    2010-09-01

    ...-000] Constellation Mystic Power, LLC; Supplemental Notice That Initial Market-Based Rate Filing... the above-referenced proceeding of Constellation Mystic Power, LLC's application for market-based rate...

  16. DEM Development from Ground-Based LiDAR Data: A Method to Remove Non-Surface Objects

    Directory of Open Access Journals (Sweden)

    Maneesh Sharma

    2010-11-01

    Full Text Available Topography and land cover characteristics can have significant effects on infiltration, runoff, and erosion processes on watersheds. The ability to model the timing and routing of surface water and erosion is affected by the resolution of the digital elevation model (DEM. High resolution ground-based Light Detecting and Ranging (LiDAR technology can be used to collect detailed topographic and land cover characteristic data. In this study, a method was developed to remove vegetation from ground-based LiDAR data to create high resolution DEMs. Research was conducted on intensively studied rainfall–runoff plots on the USDA-ARS Walnut Gulch Experimental Watershed in Southeast Arizona. LiDAR data were used to generate 1 cm resolution digital surface models (DSM for 5 plots. DSMs created directly from LiDAR data contain non-surface objects such as vegetation cover. A vegetation removal method was developed which used a slope threshold and a focal mean filter method to remove vegetation and create bare earth DEMs. The method was validated on a synthetic plot, where rocks and vegetation were added incrementally. Results of the validation showed a vertical error of ±7.5 mm in the final DEM.

  17. A combination method based on chitosan adsorption and duckweed (Lemna gibba L.) phytoremediation for boron (B) removal from drinking water.

    Science.gov (United States)

    Türker, Onur Can; Baran, Talat

    2018-01-28

    The metalloid boron (B) and its compounds widely exist in the environment, and boron can have hazardous effects on plants, animals, and human beings when it is found in high concentrations in water bodies. It is difficult and costly to remove B with conventional treatment methods from drinking water. Therefore, alternative and cost-effective treatment techniques are necessary. In this study, for the first time, a novel and environmentally friendly method based on the phytoremediation ability of chitosan and duckweed (Lemna gibba L.) combination was evaluated for B removal from drinking water. Our results from batch adsorption experiment indicated that the highest B uptake capacity of chitosan bead was found as 3.18 mg/g, and we determined the optimal B sorption occurs at pH value of 7. The Langmuir isotherm and pseudo-second-order kinetic model better fitted the equilibrium obtained for B removal. B in drinking water could be reduced to less than 2.4 mg L -1 when 0.05 g of plant-based chitosan beads and 12 L. gibba fronds were used in the 4-day treatment period.

  18. Removal of solar radiation effect based on nonlinear data processing technique for Seismo-Ionospheric Anomaly before few earthquakes

    Directory of Open Access Journals (Sweden)

    Kunvar Shardaprasad Yadav

    2016-05-01

    Full Text Available The study of ionospheric precursorsof earthquakehas gained interest among many researchers, specially the precursor obtained in terms of anomalous variation in total electron content (TEC. If earthquake occurs during a period of moderate to high solar activity, the TEC derived using global positioning system (GPS measurements requires the elimination of solar effect so as to identify the precursory signature. This paperincludes multi-resolution time series technique to remove the nonlinear effect from solar radiation on GPS-based TEC. The technique is based on wavelet transform applicable to RINEX TEC data. This technique is used to remove nonlinear background solar effect from TEC prior to four different earthquakes (M 6.0. Further in order to evaluate the extracted TEC, we obtain the correlation between the decomposed TEC A6 and measured solar index (F10.7 and extreme ultraviolet (EUV. A good correlation is obtained between decomposed TEC A6 and EUV for all the cases. This suggests that this technique is useful in removal of background solar effect for identifying earthquake precursor in TEC.

  19. Cloud-shadow removal for Unmanned Aerial System multispectral imagery based on tensor decomposition methods

    DEFF Research Database (Denmark)

    Baum, Andreas; Wang, Sheng; Garcia, Monica

    that are mosaicked into larger images to produce ortho-photomaps. Frequently, especially in northern latitudes, the images to be mosaicked have been acquired under varying irradiance conditions due to moving clouds that create artifacts in the detected signal unrelated to physical changes in vegetation properties......, this study succeeded to remove the cloud shadow effects and image noise in UAS imagery providing normalized reflectance. The comparison between the corrected and un-corrected images shows a significant improvement for reflectance estimation in the shadow areas. Further, analysis of vegetation indices e...

  20. Polymer based nanocomposites for the removal of Cr(VI) from water

    CSIR Research Space (South Africa)

    Setshedi, K

    2012-10-10

    Full Text Available .3 pH 2 pH 6 % R em ov al pH Feasibility test for Cr(VI) contaminated ground water and the effect of competing ions 100 ppm Cr(VI) sol. Nanocomposite + Cr(VI) sol 0 ppm Cr(VI) sol. 0 20 40 60 80 100 Q e( m g/ g) Cr 6+ Cr 6... nanocomposites for the removal of Cr(VI) from water Emerging Researcher Symposium Katlego Setshedi 10 October 2012 Outline ? CSIR 2012 Slide 2 ? Background ? Problem statement ? Health impacts ? Remedies ? Objectives ? Experimental procedure...

  1. Iterative l(1)-min algorithm for fixed pattern noise removal in fiber-bundle-based endoscopic imaging.

    Science.gov (United States)

    Liu, Xuan; Zhang, Lijun; Kirby, Mitchell; Becker, Richard; Qi, Shaohai; Zhao, Feng

    2016-04-01

    In this study, we developed a signal processing method for fixed pattern noise removal in fiber-bundle-based endoscopic imaging. We physically acquired the fixed pattern of the fiber bundle and used it as a prior image in an l1 norm minimization (l1-min) algorithm. We chose an iterative shrinkage thresholding algorithm for l1 norm minimization. In addition to fixed pattern noise removal, this method also improved image contrast while preserving spatial resolution. The effectiveness of this method was demonstrated on images obtained from a dark-field illuminated reflectance fiber-optic microscope (DRFM). The iterative l1-min algorithm presented in this paper, in combination with the DRFM system that we previously developed, enables high-resolution, high-sensitivity, intrinsic-contrast, and in situ cellular imaging which has great potential in clinical diagnosis and biomedical research.

  2. Sequence-based analysis of protein degradation rates

    NARCIS (Netherlands)

    Correa Marrero, Miguel; Dijk, van Aalt-Jan; Ridder, de Dick

    2017-01-01

    Protein turnover is a key aspect of cellular homeostasis and proteome dynamics. However, there is little consensus on which properties of a protein determine its lifetime in the cell. In this work, we exploit two reliable datasets of experimental protein degradation rates to learn models and uncover

  3. The removal of COD, TSS and colour of black liquor by coagulation–flocculation process at optimized pH, settling and dosing rate

    Directory of Open Access Journals (Sweden)

    Muhammad Irfan

    2017-05-01

    Full Text Available Pulp and Paper mills are generating millions of tons of wastewater and are major source of water pollution. In this research work, pulping wastes have been characterized and found to contain very high COD, TSS and colour. Coagulation–flocculation process was performed to find out the performance of different coagulants and flocculants like alum, ferric chloride, aluminium chloride, ferrous sulphate, poly aluminium chloride (PAC, cationic and anionic polyacrylamide polymers in individual form as well as in different combinations. The effects of dosing rate, settling time and pH were examined for reduction of COD, TSS and colour. Coagulants used in combinations were found to be more effective in reducing COD, TSS and colour instead of using individual form. The initial pH of the effluent for coagulation process was found to have remarkable effect on COD, TSS and colour removal. The most effective results were found using cationic and anionic polyacrylamide combination with ferric chloride and aluminium chloride and reduction of 76% COD, 95% TSS and 95% colour were observed at pH < 3.

  4. Two years survival rate of class II composite resin restorations prepared by ART with and without a chemomechanical caries removal gel in primary molars.

    Science.gov (United States)

    Topaloglu-Ak, Asli; Eden, Ece; Frencken, Jo E; Oncag, Ozant

    2009-09-01

    The aim was to test the null hypotheses that there is no difference: (1) in carious lesion development at the restoration margin between class II composite resin restorations in primary molars produced through the atraumatic restorative treatment (ART) with and without a chemomechanical caries removal gel and (2) in the survival rate of class II composite resin restorations between two treatment groups after 2 years. Three hundred twenty-seven children with 568 class II cavitated lesions were included in a parallel mouth study design. Four operators placed resin composite (Filtek Z 250) restorations bonded with a self-etch adhesive (Adper prompt L pop). Two independent examiners evaluated the restorations after 0.5, 1, and 2 years using the modified Ryge criteria. The Kaplan-Meier survival method was applied to estimate survival percentages. A high proportion of restorations were lost during the study period. Therefore, the first hypothesis could not be tested. No statistically significant difference was observed between the cumulative survival percentages of restorations produced by the two treatment approaches over the 2-year period (ART, 54.1 +/- 3.4%; ART with Carisolv, 46.0 +/- 3.4%). This hypothesis was accepted. ART with chemomechanical gel might not provide an added benefit increasing the survival percentages of ART class II composite resin restorations in primary teeth.

  5. Enhanced WWTP effluent organic matter removal in hybrid ozonation-coagulation (HOC) process catalyzed by Al-based coagulant

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xin [School of Environmental and Municipal Engineering, Xi’an University of Architecture and Technology, Xi’an, Shaanxi Province, 710055 (China); Jin, Pengkang, E-mail: pkjin@hotmail.com [School of Environmental and Municipal Engineering, Xi’an University of Architecture and Technology, Xi’an, Shaanxi Province, 710055 (China); Hou, Rui [School of Environmental and Municipal Engineering, Xi’an University of Architecture and Technology, Xi’an, Shaanxi Province, 710055 (China); Yang, Lei [Department of Materials Science and Engineering, Monash University, Clayton, VIC, 3800 (Australia); Wang, Xiaochang C., E-mail: xcwang@xauat.edu.cn [School of Environmental and Municipal Engineering, Xi’an University of Architecture and Technology, Xi’an, Shaanxi Province, 710055 (China)

    2017-04-05

    Highlights: • A novel HOC process was firstly put forward to apply in wastewater reclamation. • Interactions between ozone and Al-based coagulants was found in the HOC process. • Ozonation can be catalyzed and enhanced by Al-based coagulants in the HOC process. • HOC process showed better organics removal than pre-ozonation-coagulation process. - Abstract: A novel hybrid ozonation-coagulation (HOC) process was developed for application in wastewater reclamation. In this process, ozonation and coagulation occurred simultaneously within a single unit. Compared with the conventional pre-ozonation-coagulation process, the HOC process exhibited much better performance in removing dissolved organic matters. In particular, the maximal organic matters removal efficiency was obtained at the ozone dosage of 1 mgO{sub 3}/mg DOC at each pH value (pH 5, 7 and 9). In order to interpret the mechanism of the HOC process, ozone decomposition was monitored. The results indicated that ozone decomposed much faster in the HOC process. Moreover, by using the reagent of O{sub 3}-resistant hydroxyl radical (·OH) probe compound, para-chlorobenzoic acid (pCBA), and electron paramagnetic resonance (EPR) analysis, it was observed that the HOC process generated higher content of ·OH compared with pre-ozonation process. This indicates that the ·OH oxidation reaction as the key step can be catalyzed and enhanced by Al-based coagulants and their hydrolyzed products in this developed process. Thus, based on the catalytic effects of Al-based coagulants on ozonation, the HOC process provides a promising alternative to the conventional technology for wastewater reclamation in terms of higher efficiency.

  6. On orbit MTF measurement of remote sensing camera based on wavelet transform (notice of removal)

    Science.gov (United States)

    Li, Guangze; Wang, Xiaodong; Zhou, Huaide; Hao, Zhihang

    2006-01-01

    This paper (SPIE Paper 60310G) was removed from the SPIE Digital Library on 8 August 2008 upon learning that portions of the paper are identical or similar to material contained in a Master's Thesis by Taeyoung Choi at South Dakota State University in 2002 titled "IKONOS Satellite on Orbit Modulation Transfer Function (MTF) Measurement using Edge and Pulse Method," without attribution or credit to the source. As stated in the SPIE Publication Ethics Guidelines, "SPIE defines plagiarism as the reuse of someone else's prior ideas, processes, results, or words without explicit attribution of the original author and source, or falsely representing someone else's work as one's own. Unauthorized use of another researcher's unpublished data or findings without permission is considered to be a form of plagiarism even if the source is attributed. SPIE considers plagiarism in any form, at any level, to be unacceptable and a serious breach of professional conduct." It is SPIE policy to remove such papers and to provide citations to original sources so that interested readers can obtain the information directly from these sources.

  7. Characterization of coal gasification slag-based activated carbon and its potential application in lead removal.

    Science.gov (United States)

    Xu, Yiting; Chai, Xiaoli

    2017-03-23

    Highly porous activated carbons were prepared from a coal gasification slag (CGS) precursor, by KOH activation to remove Pb2+ from aqueous solution. The effects of pretreatment methods and activation parameters on the properties of the activated carbon were investigated, such as KOH/CGS mass ratio, activation temperature and activation time. The results showed that the maximum Brunauer-Emmett-Teller surface area and total pore volume with the value of 2481 m2 g-1 and of 1.711 cc g-1 were obtained at a KOH/CGS ratio of 3.0 by physical mixing, an activation temperature of 750°C and an activation time of 80 min. SEM, FTIR and EA analyses indicated that pronounced pores existed on the exterior surface of the activated samples, and the contents of H and O decreased due to the loss of surface chemical groups during activation. Experimental data for the Pb2+ adsorption were fitted well by Freundlich equation and a pseudo-second-order model with a maximum experimental adsorption capacity of 141 mg/g. All of the results indicated that CGS could be a promising material to prepare porous activated carbon for Pb2+ removal from wastewater.

  8. Adsorbent for resorcinol removal based on cellulose functionalized with magnetic poly(dopamine).

    Science.gov (United States)

    Ding, Chaofan; Sun, Yuanling; Wang, Yanhui; Li, Jianbo; Lin, Yanna; Sun, Weiyan; Luo, Chuannan

    2017-06-01

    A simple chemical bonding method to synthesize magnetic cellulose-poly(dopamine) (Fe3O4@CMC@PDA) was reported. The adsorption behaviors of resorcinol in aqueous solution on Fe3O4@CMC@PDA were systematically investigated. As the results shown that, with the advantage of high surface area, abundant hydroxyl and amino groups of Fe3O4@CMC@PDA, and the magnetic property of Fe3O4, the resorcinol can be easily and rapidly extracted from the water by magnetic attraction under investigation. The adsorption equilibrium of Fe3O4@CMC@PDA for resorcinol corresponded with Freundlich isotherm, and the novel adsorbent exhibited better resorcinol removal efficiency in solutions with low pH. It was found that the resorcinol adsorption performance of Fe3O4@CMC@PDA strongly depends on their surface charge concentration and specific surface area. These results provide evidences for estimating and optimizing the removal of phenols from the wastewater by using of Fe3O4@CMC@PDA composites in the future. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. ICA-AROMA: A robust ICA-based strategy for removing motion artifacts from fMRI data.

    Science.gov (United States)

    Pruim, Raimon H R; Mennes, Maarten; van Rooij, Daan; Llera, Alberto; Buitelaar, Jan K; Beckmann, Christian F

    2015-05-15

    Head motion during functional MRI (fMRI) scanning can induce spurious findings and/or harm detection of true effects. Solutions have been proposed, including deleting ('scrubbing') or regressing out ('spike regression') motion volumes from fMRI time-series. These strategies remove motion-induced signal variations at the cost of destroying the autocorrelation structure of the fMRI time-series and reducing temporal degrees of freedom. ICA-based fMRI denoising strategies overcome these drawbacks but typically require re-training of a classifier, needing manual labeling of derived components (e.g. ICA-FIX; Salimi-Khorshidi et al. (2014)). Here, we propose an ICA-based strategy for Automatic Removal of Motion Artifacts (ICA-AROMA) that uses a small (n=4), but robust set of theoretically motivated temporal and spatial features. Our strategy does not require classifier re-training, retains the data's autocorrelation structure and largely preserves temporal degrees of freedom. We describe ICA-AROMA, its implementation, and initial validation. ICA-AROMA identified motion components with high accuracy and robustness as illustrated by leave-N-out cross-validation. We additionally validated ICA-AROMA in resting-state (100 participants) and task-based fMRI data (118 participants). Our approach removed (motion-related) spurious noise from both rfMRI and task-based fMRI data to larger extent than regression using 24 motion parameters or spike regression. Furthermore, ICA-AROMA increased sensitivity to group-level activation. Our results show that ICA-AROMA effectively reduces motion-induced signal variations in fMRI data, is applicable across datasets without requiring classifier re-training, and preserves the temporal characteristics of the fMRI data. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. The future cost of electrical energy storage based on experience rates

    Science.gov (United States)

    Schmidt, O.; Hawkes, A.; Gambhir, A.; Staffell, I.

    2017-08-01

    Electrical energy storage could play a pivotal role in future low-carbon electricity systems, balancing inflexible or intermittent supply with demand. Cost projections are important for understanding this role, but data are scarce and uncertain. Here, we construct experience curves to project future prices for 11 electrical energy storage technologies. We find that, regardless of technology, capital costs are on a trajectory towards US$340 ± 60 kWh-1 for installed stationary systems and US$175 ± 25 kWh-1 for battery packs once 1 TWh of capacity is installed for each technology. Bottom-up assessment of material and production costs indicates this price range is not infeasible. Cumulative investments of US$175-510 billion would be needed for any technology to reach 1 TWh deployment, which could be achieved by 2027-2040 based on market growth projections. Finally, we explore how the derived rates of future cost reduction influence when storage becomes economically competitive in transport and residential applications. Thus, our experience-curve data set removes a barrier for further study by industry, policymakers and academics.

  11. Removal of Cu{sup 2+} and Pb{sup 2+} ions using CMC based thermoresponsive nanocomposite hydrogel

    Energy Technology Data Exchange (ETDEWEB)

    Oezkahraman, Bengi [Faculty of Engineering, Chemical Engineering Department, Hitit University, Corum (Turkey); Acar, Isil; Emik, Serkan [Faculty of Engineering, Chemical Engineering Department, Istanbul University, Avcilar-Istanbul (Turkey)

    2011-07-15

    In this study, carboxymethylcellulose (CMC) based thermoresponsive nanocomposite hydrogel was synthesized for the removal of Cu{sup 2+} and Pb{sup 2+} ions from aqueous solutions. To prepare nanocomposite hydrogel, graft copolymerization of N-isopropyl acrylamide (NIPAm) and acrylic acid (AA) onto CMC was carried out in Na-montmorillonite (MMT)/water suspension media and ammonium persulfate (APS) used as initiator. The chemical structures of hydrogels were characterized by Fourier transform infrared (FT-IR) and X-ray diffraction spectroscopy (XRD). Lower critical solution temperature (LCST), pH responsivity, swelling, and deswelling properties of the hydrogels were also examined. In addition competitive and non-competitive removal of Cu{sup 2+} and Pb{sup 2+} studies were carried out. According to heavy metal sorption studies results, removal capacities of nanocomposite hydrogel for both metal ions were found to be higher than those of pure hydrogel. The analyzed adsorption data showed that the adsorption process of Cu{sup 2+} and Pb{sup 2+} could be explained by pseudo-second order kinetic model. Moreover, according to competitive sorption studies, it is found to be that both hydrogels are more selective to Cu{sup 2+} ion rather than Pb{sup 2+}. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Effect of wastewater-borne bacteria on algal growth and nutrients removal in wastewater-based algae cultivation system.

    Science.gov (United States)

    Ma, Xiaochen; Zhou, Wenguang; Fu, Zongqiang; Cheng, Yanling; Min, Min; Liu, Yuhuan; Zhang, Yunkai; Chen, Paul; Ruan, Roger

    2014-09-01

    Centrate, a type of nutrient-rich municipal wastewater was used to determine the effect of wastewater-borne bacteria on algal growth and nutrients removal efficiency in this study. The characteristics of algal and bacterial growth profiles, wastewater nutrient removal and effect of initial algal inoculums were systematically examined. The results showed that initial algal concentration had apparent effect on bacterial growth, and the presence of bacteria had a significant influence on algal growth pattern, suggesting symbiotic relationship between algae and bacteria at the initial stage of algae cultivation. The maximum algal biomass of 2.01 g/L with 0.1g/L initial algal inoculums concentration can be obtained during algae cultivation in raw centrate medium. The synergistic effect of centrate-borne bacteria and microalgae on algae growth and nutrient removal performance at initial fast growth stage has great potential to be applied to pilot-scale wastewater-based algae wastewater system cultivated in continuous or semi-continuous mode. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Evaluation of a Full-Scale Water-Based Scrubber for Removing Siloxanes from Digester Gas: A Case Study.

    Science.gov (United States)

    Surita, Sharon C; Tansel, Berrin

    2015-05-01

    Siloxanes are becoming more prominent in digester gas at water resource recovery facilities because of their wide use in personal care products. This study evaluates a full-scale water-based scrubber operating in a water resource recovery facility (Miami, FL). The digester gas is used for energy generation due to its high methane content. During energy generation, siloxanes are converted to silicates and Silicon Dioxide (SiO2), which leave deposits on engine components. Trimethylsilanol (TMSOH), Octamethyltrisiloxane (L3), Hexamethylcyclotrisiloxane (D3), Octamethylcyclotetrasiloxane (D4), Decamethylcyclopentasiloxane (D5), and Dodecamethylcyclohexasiloxane (D6) were detected in the digester gas. D4 and D5 were present at the highest concentrations, 5000 and 1800 μg/ m3, respectively. Sampling results have indicated that scrubbers employed for hydrogen sulfide (H2S) removal at the facility do not provide effective removal of siloxanes due to their high Henry's Constant. Post scrubber treatment is needed to remove siloxanes from the digester gas prior to combustion.

  14. Automated solvent artifact removal and base plane correction from multidimensional NMR protein spectra by Auremol-SSA

    Energy Technology Data Exchange (ETDEWEB)

    Malloni, Wilhelm Massimiliano; Sanctis, Silvia de; Lang, Elmar W.; Kalbitzer, Hans Robert [Institut fuer Biophysik und Physikalische Biochemie, Universitaet Regensburg (Germany); Neidig, Klaus-Peter [Bruker Biospin GmbH, Software Abteilung (Germany)

    2010-07-01

    Strong solvent signals lead to a disappearance of weak protein signals close to the solvent resonance frequency and to base plane variations all over the spectrum. AUREMOL-SSA method provides an automated approach for solvent artifact removal from multidimensional NMR protein spectra. Its core algorithm is based on singular spectrum analysis (SSA) in the time domain and it is combined with an automated base plane correction in the frequency domain. The SSA technique is an extension of the PCA applied to a time lagged data set that embeds each FID separately in an M-dimensional vector space. The performance of the method has been tested on synthetic and experimental spectra including a two-dimensional NOESY spectrum and a three-dimensional 1H,13C-HCCH-TOCSY spectrum. An extension of the FLATT algorithm for base points selection has been introduced after the solvent removal. Those pure baseline regions are then linearly interpolated and subtracted from the original spectrum. The advantage for practical applications is the complete automation that includes the SSA followed by filtering Fourier transformation, phase correction related to the group delay management and baseline correction.

  15. New Solid-Base Cu-MgO for CO2 Capture at 473 K and Removal of Nitrosamine.

    Science.gov (United States)

    Li, Yan Y; Dong, Xin Y M; Sun, Xiao D; Wang, Ying; Zhu, Jian H

    2016-11-09

    To fabricate a new solid base with high efficiency in the adsorption of CO2 at 473 K and catalytic activity in the degradation of nitrosamines, magnesium oxalate and copper nitrate are mixed with the assistance of microwave irradiation followed by calcination to immobilize CuO among MgO particles. The binary solid base CuO-MgO is thus moderately reduced to form the Cu-inserted MgO composite with highly exposed strong basic sites, and it can capture 34.6 mg g-1 of CO2 in the harsh instantaneous adsorption at 473 K and keep a high strong basicity while trapping the CO2 mixed with SO2 and NO. Besides this, the new solid base exhibits high activity in the removal of volatile nitrosamine N-nitrosopyrrolidine (NPYR), for the first time expanding the application of solid bases to environmental catalysis.

  16. Effects of shock 2,4-dichlorophenol (DCP) and cod loading rates on the removal of 2,4-DCP in a sequential upflow anaerobic sludge blanket/aerobic completely stirred tank reactor system.

    Science.gov (United States)

    Uluköy, A; Sponza, D T

    2008-04-01

    The treatability of 2,4-dwichlorophenol (DCP) was studied in an anaerobic/aerobic sequential reactor system. Laboratory scale upflow anaerobic sludge blanket (UASB) reactor/completely stirred tank reactors (CSTR) were operated at constant 2,4-DCP concentrations, and increasing chemical oxygen demand (COD) loading rates. The effect of shock organic loading rates on 2,4-DCP, COD removal efficiencies and methane gas production were investigated in the UASB reactor. When the organic loading rate was increased from 3.6 g l(-1) d(-1) to 30.16 g l(-1) d(-1), the COD and 2,4-DCP removal efficiencies decreased from 80 to 25% and from 99 to 60% in the UASB reactor. The optimum organic loading rates for maximum 2,4-DCP (E=99-100%) and COD (E=65-85%) removal efficiencies were 25-30 and 8-20 g-COD l(-1) d(-1), respectively. The percentage of methane of the total gas varied between 70 and 80 while the organic loadings were 18 g-COD l(-1) d(-1) and 20.36 g-COD l(-1) d(-1), respectively. During 80 days of operation, 2,4-DCP concentration was found to be below 0.5 and 0.1 mg l(-1) in aerobic reactor effluent resulting in 78 and 100% removal efficiencies. When the hydraulic retention time (HRT) was 18.72 h, the 2,4-DCP removal efficiency was 97% in the aerobic reactor. The optimum COD removal efficiency was 78.83% in anaerobic reactor effluent at an influent COD loading rate of 7.238 g-COD l(-1) d(-1) while 83.6% maximum COD removal efficiency was obtained in the aerobic reactor, resulting in a total COD removal efficiency of 96.83% in the whole system. The 2,4-DCP removal efficiency was 99% in the sequential anaerobic (UASB)/aerobic (CSTR) reactor system at COD loading rates varying between 11.46 and 30.16 g-COD l(-1) d(-1).

  17. The plant virus microscope image registration method based on mismatches removing.

    Science.gov (United States)

    Wei, Lifang; Zhou, Shucheng; Dong, Heng; Mao, Qianzhuo; Lin, Jiaxiang; Chen, Riqing

    2016-01-01

    The electron microscopy is one of the major means to observe the virus. The view of virus microscope images is limited by making specimen and the size of the camera's view field. To solve this problem, the virus sample is produced into multi-slice for information fusion and image registration techniques are applied to obtain large field and whole sections. Image registration techniques have been developed in the past decades for increasing the camera's field of view. Nevertheless, these approaches typically work in batch mode and rely on motorized microscopes. Alternatively, the methods are conceived just to provide visually pleasant registration for high overlap ratio image sequence. This work presents a method for virus microscope image registration acquired with detailed visual information and subpixel accuracy, even when overlap ratio of image sequence is 10% or less. The method proposed focus on the correspondence set and interimage transformation. A mismatch removal strategy is proposed by the spatial consistency and the components of keypoint to enrich the correspondence set. And the translation model parameter as well as tonal inhomogeneities is corrected by the hierarchical estimation and model select. In the experiments performed, we tested different registration approaches and virus images, confirming that the translation model is not always stationary, despite the fact that the images of the sample come from the same sequence. The mismatch removal strategy makes building registration of virus microscope images at subpixel accuracy easier and optional parameters for building registration according to the hierarchical estimation and model select strategies make the proposed method high precision and reliable for low overlap ratio image sequence. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Cu-based metal-organic framework/activated carbon composites for sulfur compounds removal

    Science.gov (United States)

    Shi, Rui-Hua; Zhang, Zhen-Rong; Fan, Hui-Ling; Zhen, Tian; Shangguan, Ju; Mi, Jie

    2017-02-01

    MOF-199 was modified by incorporating activated carbon (AC) during its synthesis under hydrothermal conditions to improve its performance in the removal of hydrogen sulfide (H2S) and dimethyl sulfide (CH3SCH3). A variety of different characterization techniques including X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, nitrogen adsorption/desorption isotherms, scanning electron microscopy (SEM), pyridine adsorption infrared spectroscopy (Py-IR), thermogravimetric- mass spectroscopy (TG-MS) and X-ray photoelectron spectroscopy (XPS) were used to analyze the fresh and exhausted composites. It was found that the composites, which have an amount of AC of less than 2%, had the same morphology as those of pristine MOF-199, but exhibited a more ordered crystallinity structure as well as higher surface area. The composite with 2% AC incorporation showed highest sulfur capacity of 8.46 and 8.53% for H2S and CH3SCH3, respectively, which increased by 51 and 41% compared to that of MOF-199. This improvement was attributed to the formation of more micropores and especially the increased number of unsaturated copper metal sites, as revealed by Py-IR. It is suggested the chemical reaction was apparent during adsorption of H2S, which resulted in the formation of CuS and the collapse of the MOF structure. Whereas reversible chemisorption was found for CH3SCH3 adsorption, as testified by TG-MS and fixed-bed regeneration. Exhausted MAC-2 can be almost totally regenerated by high temperature 180 °C nitrogen purge, indicating a promising adsorbent for CH3SCH3 removal.

  19. Silver-based getters for {sup 129}I removal from low-activity waste

    Energy Technology Data Exchange (ETDEWEB)

    Asmussen, R. Matthew; Neeway, James J.; Lawter, Amanda R.; Wilson, Andrew; Qafoku, Nikolla P. [Pacific Northwest National Laboratory, Richland, WA (United States). Geosciences Group

    2016-07-01

    A prominent radionuclide of concern in nuclear wastes, {sup 129}I, is present in low-activity wastes (LAW) at the Hanford site. Several Ag-containing materials were tested as immobilization agents, or ''getters'', for I (as iodide, I{sup -}) removal from deionized (DI) water and a liquid LAW simulant: Ag impregnated activate carbon (Ag-C), Ag exchanged zeolite (Ag-Z), and argentite. In anoxic batch experiments with DI water, the Ag-C and argentite were most effective, with maximum K{sub d} values of 6.2 x 10{sup 5} mL/g for the Ag-C and 3.7 x 10{sup 5} mL/g for the argentite after 15 days. Surface area and Ag content were found to influence the performance of the getters in DI water. In the anoxic batch experiments with LAW simulant, Ag-Z vastly outperformed the other getters with K{sub d} values of 2.2 x 10{sup 4} mL/g at 2 h, which held steady until 15 days, compared with 1.8 x 10{sup 3} mL/g reached at 15 days by the argentite. All getters were stable over long periods of time (i.e. 40 days) in DI water, while the Ag-Z and argentite were also stable in the LAW simulant. Ag-Z was found to have consistent I removal upon crushing to a smaller particle size and in the presence of O{sub 2}, making it a strong candidate for the treatment of LAW containing I.

  20. Removal of triazine-based pollutants from water by carbon nanotubes: Impact of dissolved organic matter (DOM) and solution chemistry.

    Science.gov (United States)

    Engel, Maya; Chefetz, Benny

    2016-12-01

    Adsorption of organic pollutants by carbon nanotubes (CNTs) in the environment or removal of pollutants during water purification require deep understanding of the impacts of the presence of dissolved organic matter (DOM). DOM is an integral part of environmental systems and plays a key role affecting the behavior of organic pollutants. In this study, the effects of solution chemistry (pH and ionic strength) and the presence of DOM on the removal of atrazine and lamotrigine by single-walled CNTs (SWCNTs) was investigated. The solubility of atrazine slightly decreased (∼5%) in the presence of DOM, whereas that of lamotrigine was significantly enhanced (by up to ∼70%). Simultaneous introduction of DOM and pollutant resulted in suppression of removal of both atrazine and lamotrigine, which was attributed to DOM-pollutant competition or blockage of adsorption sites by DOM. However the decrease in removal of lamotrigine was also a result of its complexation with DOM. Pre-introduction of DOM significantly reduced pollutant adsorption by the SWCNTs, whereas introduction of DOM after the pollutant resulted in the release of adsorbed atrazine and lamotrigine from the SWCNTs. These data imply that DOM exhibits higher affinity for the adsorption sites than the triazine-based pollutants. In the absence of DOM atrazine was a more effective competitor than lamotrigine for adsorption sites in SWCNTs. However, competition between pollutants in the presence of DOM revealed lamotrigine as the better competitor. Our findings help unravel the complex DOM-organic pollutant-CNT system and will aid in CNT-implementation in water-purification technologies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Zirconium-based metal organic frameworks: Highly selective adsorbents for removal of phosphate from water and urine

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Kun-Yi Andrew, E-mail: linky@nchu.edu.tw [Department of Environmental Engineering, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung, Taiwan (China); Chen, Shen-Yi [Department of Environmental Engineering, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung, Taiwan (China); Jochems, Andrew P. [New Mexico Bureau of Geology & Mineral Resources and New Mexico Institute of Mining & Technology, Socorro, NM (United States)

    2015-06-15

    Phosphate is one of the most concerning compounds in wastewater streams and a main nutrient that causes eutrophication. To eliminate the phosphate pollution, Metal Organic Frameworks (MOFs) are proposed in this study as adsorbents to remove phosphate from water. The zirconium-based MOF, UiO-66, was selected as representative MOF given its exceptional stability in water. To investigate the effect of an amine functional group, UiO-66-NH2 was also prepared using an amine-substituted ligand. The adsorption kinetics and isotherm reveal that UiO-66-NH2 exhibited higher adsorption capacities than UiO-66 possibly due to the amine group. However, the interaction between phosphate and zirconium sites of UiO MOFs might be the primary factor accounting for the phosphate adsorption to UiO MOFs. UiO MOFs also exhibited a high selectivity towards phosphate over other anions such as bromate, nitrite and nitrate. Furthermore, UiO MOFs were found to adsorb phosphate and to completely remove diluted phosphate in urine. We also found that UiO MOFs could be easily regenerated and re-used for phosphate adsorption. These findings suggest that UiO MOFs can be effective and selective adsorbents to remove phosphate from water as well as urine. - Highlights: • UiO-66 as the first type of MOFs was used to remove phosphate from water and urine. • The amine group in UiO MOFs was found to enhance the phosphate adsorption. • UiO-66 exhibited a high adsorption selectivity towards phosphate over other anions. • UiO-66 could be easily regenerated and re-used with 85% regeneration efficiency.

  2. The impact of statistical choices on neonatal intensive care unit quality ratings based on nosocomial infection rates.

    Science.gov (United States)

    Lee, Henry C; Chien, Alyna T; Bardach, Naomi S; Clay, Ted; Gould, Jeffrey B; Dudley, R Adams

    2011-05-01

    To examine the extent to which performance assessment methods affect the percentage of neonatal intensive care units (NICUs) and very low-birth-weight (VLBW) infants included in performance assessments, the distribution of NICU performance ratings, and the level of agreement in those ratings. Cross-sectional study based on risk-adjusted nosocomial infection rates. NICUs belonging to the California Perinatal Quality Care Collaborative 2007-2008. One hundred twenty-six California NICUs and 10 487 VLBW infants. Three performance assessment choices: (1) excluding "low-volume" NICUs (those caring for <30 VLBW infants per year) vs a criterion based on confidence intervals, (2) using Bayesian vs frequentist hierarchical models, and (3) pooling data across 1 vs 2 years. Proportion of NICUs and patients included in quality assessment, distribution of ratings for NICUs, and agreement between methods using the κ statistic. Depending on the methods applied, 51% to 85% of NICUs and 72% to 96% of VLBW infants were included in performance assessments, 76% to 87% of NICUs were considered "average," and the level of agreement between NICU ratings ranged from 0.23 to 0.89. The percentage of NICUs included in performance assessments and their ratings can shift dramatically depending on performance measurement method. Physicians, payers, and policymakers should continue to closely examine which existing performance assessment methods are most appropriate for evaluating pediatric care quality.

  3. Observable Social Cognition: A Rating Scale (OSCARS): An Interview-Based Assessment for Schizophrenia

    Science.gov (United States)

    Healey, Kristin M.; Combs, Dennis R.; Gibson, Clare M.; Keefe, Richard S.E.; Roberts, David L.; Penn, David L.

    2015-01-01

    Introduction Individuals with schizophrenia consistently show impairments in social cognition (SC). SC has become a potential treatment target due to its association with functional outcomes. An alternative method of assessment is to administer an observer-based scale incorporating an informant’s “first hand” impressions in ratings. Methods The present study used the Observable Social Cognition: A Rating Scale (OSCARS) in 62 outpatients and 50 non-psychiatric controls (NPCs) to assess performance in domains of SC (e.g. emotion perception, theory of mind). Results The OSCARS demonstrated sufficient internal consistency and test-retest reliability. Construct validity was assessed through an exploratory factor analysis. Patient OSCARS indices were not significantly correlated with measures of SC with the exception of aggressive attributional style. Individuals with less impairment in SC reacted more aggressively to ambiguous situations. NPC OSCARS were significantly correlated with measures of theory of mind and attributional style. In a combined sample of patients and controls, six of eight items were significantly correlated with the SC task assessing the same domain, providing modest evidence of convergent validity. In patients, the OSCARS was significantly correlated with measures of functional outcome and neurocognition. Lastly, the OSCARS was found to be significantly associated with functional outcome after the influence of objective measures of SC was statistically removed. Conclusions The present study provides preliminary evidence that the OSCARS may be useful for clinicians in collecting data about patients’ potential real-world SC deficits, in turn increasing the degree to which these impairments may be targeted in treatment. PMID:25675960

  4. Rate-based structural health monitoring using permanently installed sensors.

    Science.gov (United States)

    Corcoran, Joseph

    2017-09-01

    Permanently installed sensors are becoming increasingly ubiquitous, facilitating very frequent in situ measurements and consequently improved monitoring of 'trends' in the observed system behaviour. It is proposed that this newly available data may be used to provide prior warning and forecasting of critical events, particularly system failure. Numerous damage mechanisms are examples of positive feedback; they are 'self-accelerating' with an increasing rate of damage towards failure. The positive feedback leads to a common time-response behaviour which may be described by an empirical relation allowing prediction of the time to criticality. This study focuses on Structural Health Monitoring of engineering components; failure times are projected well in advance of failure for fatigue, creep crack growth and volumetric creep damage experiments. The proposed methodology provides a widely applicable framework for using newly available near-continuous data from permanently installed sensors to predict time until failure in a range of application areas including engineering, geophysics and medicine.

  5. Rate-based structural health monitoring using permanently installed sensors

    Science.gov (United States)

    Corcoran, Joseph

    2017-09-01

    Permanently installed sensors are becoming increasingly ubiquitous, facilitating very frequent in situ measurements and consequently improved monitoring of `trends' in the observed system behaviour. It is proposed that this newly available data may be used to provide prior warning and forecasting of critical events, particularly system failure. Numerous damage mechanisms are examples of positive feedback; they are `self-accelerating' with an increasing rate of damage towards failure. The positive feedback leads to a common time-response behaviour which may be described by an empirical relation allowing prediction of the time to criticality. This study focuses on Structural Health Monitoring of engineering components; failure times are projected well in advance of failure for fatigue, creep crack growth and volumetric creep damage experiments. The proposed methodology provides a widely applicable framework for using newly available near-continuous data from permanently installed sensors to predict time until failure in a range of application areas including engineering, geophysics and medicine.

  6. Enhanced WWTP effluent organic matter removal in hybrid ozonation-coagulation (HOC) process catalyzed by Al-based coagulant.

    Science.gov (United States)

    Jin, Xin; Jin, Pengkang; Hou, Rui; Yang, Lei; Wang, Xiaochang C

    2017-04-05

    A novel hybrid ozonation-coagulation (HOC) process was developed for application in wastewater reclamation. In this process, ozonation and coagulation occurred simultaneously within a single unit. Compared with the conventional pre-ozonation-coagulation process, the HOC process exhibited much better performance in removing dissolved organic matters. In particular, the maximal organic matters removal efficiency was obtained at the ozone dosage of 1mgO3/mg DOC at each pH value (pH 5, 7 and 9). In order to interpret the mechanism of the HOC process, ozone decomposition was monitored. The results indicated that ozone decomposed much faster in the HOC process. Moreover, by using the reagent of O3-resistant hydroxyl radical (OH) probe compound, para-chlorobenzoic acid (pCBA), and electron paramagnetic resonance (EPR) analysis, it was observed that the HOC process generated higher content of OH compared with pre-ozonation process. This indicates that the OH oxidation reaction as the key step can be catalyzed and enhanced by Al-based coagulants and their hydrolyzed products in this developed process. Thus, based on the catalytic effects of Al-based coagulants on ozonation, the HOC process provides a promising alternative to the conventional technology for wastewater reclamation in terms of higher efficiency. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Preoperative regional maximal removal rate of technetium-99m-galactosyl human serum albumin is correlated with liver functional parameters, but did not predict postoperative morbidity.

    Science.gov (United States)

    Yano, Koichi; Nanashima, Atsushi; Fujii, Yoshiro; Hiyoshi, Masahide; Imamura, Naoya; Hamada, Takeomi; Tsuchimochi, Yuki; Wada, Takashi; Mizutani, Yoichi; Hirai, Toshinori

    2017-08-01

    Recently, posthepatectomy complications have been predicted by advances of new liver functional parameters, and the technetium-99m-galactosyl human serum albumin (GSA) liver scintigraphy has been applied widely for this purpose. We evaluated the clinical significance of the regional maximal removal rate (GSA-Rmax) in patients with various liver diseases as predictors of posthepatectomy complications. Between 2012 and March 2016, we examined 200 patients who underwent hepatectomy for liver and biliary diseases. The patients' background liver conditions included chronic viral liver diseases in 147 patients, normal liver in 44 patients, and others in nine patients. Hepatectomy-related postoperative complications (i.e. long-term ascites, intra-abdominal infection, and hepatic failure) occurred in 69 (35%) patients. A multivariate logistic analysis was carried out to detect the predictive parameters for complications. The median and mean preoperative GSA-Rmax was 0.420 and 0.448±0.148 mg/min, respectively. The GSA-Rmax was significantly correlated with liver functional parameters of ICGR15, LHL15, HH15, platelet count, prothrombin activity, and serum hyaluronic acid level (P<0.01), and was significantly correlated with postoperative total bilirubin level and C-reactive protein level (P<0.05). With respect to patient outcomes, GSA-Rmax was significantly lower in patients with long-term ascites (P<0.05). The predictive cutoff value for posthepatectomy long-term ascites for GSA-Rmax was 0.421 mg/min. However, the multivariate logistic regression analysis identified that a higher serum hyaluronic acid level and a lower platelet count were significant, independent factors, but not lower GSA-Rmax. GSA-Rmax is one of the liver functional parameters and is a complementary parameter to predict postoperative hyperbilirubinemia, inflammatory responses, and ascites when Tc-GSA scintigraphy is performed.

  8. Cataract removal

    Science.gov (United States)

    ... eye diseases and eye surgery. Adults are usually awake for the procedure. Numbing medicine (local anesthesia) is ... removed. Tips for recovering after cataract surgery: Wear dark sunglasses outside after you remove the patch. Wash ...

  9. Nevus Removal

    Science.gov (United States)

    ... find the answers you seek. What are the Negative Effects of Nevus Removal? Removal procedures are major ... Reunited Donor Challenge Met! Find Nevus Outreach on Facebook To New Parents of a Child With a ...

  10. Cu-based metal–organic framework/activated carbon composites for sulfur compounds removal

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Rui-Hua [State Key Laboratory of Coal Science and Technology, Co-founded by Shanxi Province and the Ministry of Science and Technology, Institute for Chemical Engineering of Coal, Taiyuan University of Technology, West Yingze Street Number 79, Taiyuan 030024 (China); Zhang, Zhen-Rong [Institute of Applied Chemical, Shanxi (China); Fan, Hui-Ling, E-mail: fanhuiling@tyut.edu.cn [State Key Laboratory of Coal Science and Technology, Co-founded by Shanxi Province and the Ministry of Science and Technology, Institute for Chemical Engineering of Coal, Taiyuan University of Technology, West Yingze Street Number 79, Taiyuan 030024 (China); Zhen, Tian [Deparment of Analysis and Service Center Micromertics instrumental Ltd, Shanghai (China); Shangguan, Ju; Mi, Jie [State Key Laboratory of Coal Science and Technology, Co-founded by Shanxi Province and the Ministry of Science and Technology, Institute for Chemical Engineering of Coal, Taiyuan University of Technology, West Yingze Street Number 79, Taiyuan 030024 (China)

    2017-02-01

    Highlights: • Incorporation of AC less than 2% in MOF-199 can increase micropores and BET surface area, as evidenced by N{sub 2} adsorption. • Lewis acid (unsaturated copper) sites could also be increased in the modified MOF-199, as revealed by Py-IR characterization. • Composite with 2% AC showed highest sulfur capacity with 8.46 and 8.53% for H{sub 2}S and CH{sub 3}SCH{sub 3}, respectively. • The adsorption of CH{sub 3}SCH{sub 3} on composite is reversible, physic-adsorption and weak chemisorption were involved. - Abstract: MOF-199 was modified by incorporating activated carbon (AC) during its synthesis under hydrothermal conditions to improve its performance in the removal of hydrogen sulfide (H{sub 2}S) and dimethyl sulfide (CH{sub 3}SCH{sub 3}). A variety of different characterization techniques including X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, nitrogen adsorption/desorption isotherms, scanning electron microscopy (SEM), pyridine adsorption infrared spectroscopy (Py-IR), thermogravimetric- mass spectroscopy (TG-MS) and X-ray photoelectron spectroscopy (XPS) were used to analyze the fresh and exhausted composites. It was found that the composites, which have an amount of AC of less than 2%, had the same morphology as those of pristine MOF-199, but exhibited a more ordered crystallinity structure as well as higher surface area. The composite with 2% AC incorporation showed highest sulfur capacity of 8.46 and 8.53% for H{sub 2}S and CH{sub 3}SCH{sub 3}, respectively, which increased by 51 and 41% compared to that of MOF-199. This improvement was attributed to the formation of more micropores and especially the increased number of unsaturated copper metal sites, as revealed by Py-IR. It is suggested the chemical reaction was apparent during adsorption of H{sub 2}S, which resulted in the formation of CuS and the collapse of the MOF structure. Whereas reversible chemisorption was found for CH{sub 3}SCH{sub 3} adsorption, as

  11. Contingency inferences driven by base rates: Valid by sampling

    Directory of Open Access Journals (Sweden)

    Florian Kutzner

    2011-04-01

    Full Text Available Fiedler et al. (2009, reviewed evidence for the utilization of a contingency inference strategy termed pseudocontingencies (PCs. In PCs, the more frequent levels (and, by implication, the less frequent levels are assumed to be associated. PCs have been obtained using a wide range of task settings and dependent measures. Yet, the readiness with which decision makers rely on PCs is poorly understood. A computer simulation explored two potential sources of subjective validity of PCs. First, PCs are shown to perform above chance level when the task is to infer the sign of moderate to strong population contingencies from a sample of observations. Second, contingency inferences based on PCs and inferences based on cell frequencies are shown to partially agree across samples. Intriguingly, this criterion and convergent validity are by-products of random sampling error, highlighting the inductive nature of contingency inferences.

  12. Umbilical necrosis rates after abdominal-based microsurgical breast reconstruction.

    Science.gov (United States)

    Ricci, Joseph A; Kamali, Parisa; Becherer, Babette E; Curiel, Daniel; Wu, Winona; Tobias, Adam M; Lin, Samuel J; Lee, Bernard T

    2017-07-01

    Umbilical stalk necrosis represents a rare, yet important complication after abdominal-based microsurgical breast reconstruction, which is both underrecognized and understudied in the literature. Once identified, umbilical reconstruction can be an extremely challenging problem. All consecutive breast free flaps at a single institution from February 2004 to February 2016 were reviewed, excluding non-abdominal-based flaps. Patients were divided based on the development of umbilical necrosis postoperatively. Demographics, surgical characteristics, and other complications were compared between the groups. A total of 918 patients met the inclusion criteria, with 29 developing umbilical necrosis identified (3.2%). Patients developing necrosis tended to be older (49.4 yrs versus 52.9 yrs; P necrosis was also associated with increased flap weight (830 g versus 656 g; P necrosis was not associated with any concomitant complications. Umbilical stalk necrosis was found to occur in 3.2% of patients and was associated with several preoperative comorbidities and intraoperative characteristics. This information should help influence intraoperative decision-making to prevent the development of this undesirable complication. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Effects of constructed wetland design on ibuprofen removal – A mesocosm scale study

    DEFF Research Database (Denmark)

    Zhang, Liang; Lyu, Tao; Zhang, Yang

    2017-01-01

    This study aimed to investigate the effects of constructed wetland design (unsaturated, saturated and aerated saturated) and plant species (Juncus, Typha, Berula, Phragmites and Iris) on the mass removal and removal kinetics of the pharmaceutical ibuprofen. Planted systems had higher ibuprofen...... removal rates (29%–99%) than in the unplanted ones (15%–85%) in all designs. The use of forced aeration improved ibuprofen removal only in the unplanted mesocosms. In general, ibuprofen removal followed an area-based first-order removal kinetics model with removal rate coefficients (kA) varying between 3...... and 35 cm/d. The ibuprofen removal was mainly attributed to microbial degradation by the fixed bed biofilm, but plant uptake and degradation within plant tissues also occurred. The ibuprofen removal was positively correlated with the oxygen concentration in the water and the removal of nutrients...

  14. Fluorescence background removal method for biological Raman spectroscopy based on empirical mode decomposition.

    Science.gov (United States)

    Leon-Bejarano, Maritza; Dorantes-Mendez, Guadalupe; Ramirez-Elias, Miguel; Mendez, Martin O; Alba, Alfonso; Rodriguez-Leyva, Ildefonso; Jimenez, M

    2016-08-01

    Raman spectroscopy of biological tissue presents fluorescence background, an undesirable effect that generates false Raman intensities. This paper proposes the application of the Empirical Mode Decomposition (EMD) method to baseline correction. EMD is a suitable approach since it is an adaptive signal processing method for nonlinear and non-stationary signal analysis that does not require parameters selection such as polynomial methods. EMD performance was assessed through synthetic Raman spectra with different signal to noise ratio (SNR). The correlation coefficient between synthetic Raman spectra and the recovered one after EMD denoising was higher than 0.92. Additionally, twenty Raman spectra from skin were used to evaluate EMD performance and the results were compared with Vancouver Raman algorithm (VRA). The comparison resulted in a mean square error (MSE) of 0.001554. High correlation coefficient using synthetic spectra and low MSE in the comparison between EMD and VRA suggest that EMD could be an effective method to remove fluorescence background in biological Raman spectra.

  15. Isolation, identification and removal of filamentous organism from SND based SBR degrading nitrophenols.

    Science.gov (United States)

    Kulkarni, P M

    2012-06-01

    Four identical lab scale sequencing batch reactors R, R1, R2, and R3, were used to assess nitrophenol biodegradation using a single sludge biomass containing Thiosphaera pantotropha. Nitrophenols [4-Nitrophenol (4-NP), 2,4-dinitrophenol (2,4-DNP) and 2,4,6-trinitrophenol (2,4,6-TNP)] were biotransformed by heterotrophic nitrification and aerobic denitrification (SND). Reactor R was used as background control, whereas R1, R2, and R3 were fed with 4-NP, 2,4-DNP, and 2,4,6-TNP, respectively. The concentration of each nitrophenol was gradually increased from 2.5 to 200 mg/l along with increase in COD, during acclimation studies. The final COD maintained was 4,500 mg/l with each nitrophenolic loading of 200 mg/l. During late phase of acclimation and HRT study, a filamentous organism started appearing in 2,4-DNP and 2,4,6-TNP bioreactors. Filaments were never found in 4-NP and background control reactor. Biochemistry and physiology behind filamentous organism development, was studied to obtain permanent solution for its removal. The effect of different input parameters such as COD loading, DO levels, SVI etc. were analyzed. The morphology and development of filamentous organism were examined extensively using microscopic techniques involving ESEM, oil immersion, phase contrast, and dark field microscopy. The organism was grown and isolated on selective agar plates and was identified as member of Streptomyses species.

  16. Alginate Production from Alternative Carbon Sources and Use of Polymer Based Adsorbent in Heavy Metal Removal

    Directory of Open Access Journals (Sweden)

    Çiğdem Kıvılcımdan Moral

    2016-01-01

    Full Text Available Alginate is a biopolymer composed of mannuronic and guluronic acids. It is harvested from marine brown algae; however, alginate can also be synthesized by some bacterial species, namely, Azotobacter and Pseudomonas. Use of pure carbohydrate sources for bacterial alginate production increases its cost and limits the chance of the polymer in the industrial market. In order to reduce the cost of bacterial alginate production, molasses, maltose, and starch were utilized as alternative low cost carbon sources in this study. Results were promising in the case of molasses with the maximum 4.67 g/L of alginate production. Alginates were rich in mannuronic acid during early fermentation independent of the carbon sources while the highest guluronic acid content was obtained as 68% in the case of maltose. The polymer was then combined with clinoptilolite, which is a natural zeolite, to remove copper from a synthetic wastewater. Alginate-clinoptilolite beads were efficiently adsorbed copper up to 131.6 mg Cu2+/g adsorbent at pH 4.5 according to the Langmuir isotherm model.

  17. Titanium removable denture based on a one-metal rehabilitation concept.

    Science.gov (United States)

    Ohkubo, Chikahiro; Sato, Yohei; Nishiyama, Yuichiro; Suzuki, Yasunori

    2017-09-26

    The use of a single metal for all restorations would be necessary because it protects against metal corrosion caused by the contact of different metals. For this "one-metal rehabilitation" concept, non-alloyed commercially pure (CP) titanium should be used for all restorations. Titanium frameworks have been cast and used for the long term without catastrophic failure, whereas they have been fabricated recently using computer-aided design/computer-aided manufacturing (CAD/CAM). However, the milling process for the frameworks of removable partial dentures (RPDs) is not easy because they have very complicated shapes and consist of many components. Currently, the fabrication of RPD frameworks has been challenged by one-process molding using repeated laser sintering and high-speed milling. Laser welding has also been used typically for repairing and rebuilding titanium frameworks. Although laboratory and clinical problems still remain, the one-metal rehabilitation concept using CP titanium as a bioinert metal can be recommended for all restorations.

  18. Reducing Moose-Vehicle Collisions through Salt Pool Removal and Displacement: an Agent-Based Modeling Approach

    Directory of Open Access Journals (Sweden)

    Paul D. Grosman

    2009-12-01

    Full Text Available Between 1990 and 2002, more than 200 moose-vehicle collisions occurred each year in Quebec, including about 50/yr in the Laurentides Wildlife Reserve. One cause is the presence of roadside salt pools that attract moose near roads in the spring and summer. Using the computer simulation technique of agent-based modeling, this study investigated whether salt pool removal and displacement, i.e., a compensatory salt pool set up 100 to 1500 m away from the road shoulder, would reduce the number of moose-vehicle collisions. Moose road crossings were used as a proxy measure. A GPS telemetry data set consisting of approximately 200,000 locations of 47 moose over 2 yr in the Laurentides Wildlife Reserve was used as an empirical basis for the model. Twelve moose were selected from this data set and programmed in the model to forage and travel in the study area. Five parameters with an additional application of stochasticity were used to determine moose movement between forest polygons. These included food quality; cover quality, i.e., protection from predators and thermal stress; proximity to salt pools; proximity to water; and slope. There was a significant reduction in road crossings when either all or two thirds of the roadside salt pools were removed, with and/or without salt pool displacement. With 100% salt pool removal, the reduction was greater (49% without compensatory salt pools than with them (18%. When two thirds of the salt pools were removed, the reduction was the same with and without compensatory salt pools (16%. Although moose-vehicle collisions are not a significant mortality factor for the moose population in the Laurentides Wildlife Reserve, in areas with higher road densities, hunting pressure, and/or predator densities it could mean the difference between a stable and a declining population, and salt pool removal could be part of a good mitigation plan to halt population declines. This model can be used, with improvements such as

  19. Adsorption Removal of Glycidyl Esters from Palm Oil and Oil Model Solution by Using Acid-Washed Oil Palm Wood-Based Activated Carbon: Kinetic and Mechanism Study.

    Science.gov (United States)

    Cheng, Weiwei; Liu, Guoqin; Wang, Xuede; Han, Lipeng

    2017-11-08

    Acid-washed oil palm wood-based activated carbon (OPAC) has been investigated for its potential application as a promising adsorbent in the removal of glycidyl esters (GEs) from both palm oil and oil model (hexadecane) solution. It was observed that the removal rate of GEs in palm oil was up to >95%, which was significantly higher than other adsorbents used in this study. In batch adsorption system, the adsorption efficiency and performance of acid-washed OPAC were evaluated as a function of several experimental parameters such as contact time, initial glycidyl palmitate (PGE) concentration, adsorbent dose, and temperature. The Langmuir, Freundlich, and Dubinin-Radushkevich models were used to describe the adsorption equilibrium isotherm, and the equilibrium data were fitted best by the Langmuir model. The maximum adsorption capacity of acid-washed OPAC was found to be 36.23 mg/g by using the Langmuir model. The thermodynamic analysis indicated that the adsorption of PGE on acid-washed OPAC was an endothermic and physical process in nature. The experimental data were fitted by using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. It was found that the kinetic of PGE adsorption onto acid-washed OPAC followed well the pseudo-second-order model for various initial PGE concentrations and the adsorption process was controlled by both film diffusion and intraparticle diffusion. The desorption test indicated the removal of GEs from palm oil was attributed to not only the adsorption of GEs on acid-washed OPAC, but also the degradation of GEs adsorbed at activated sites with acidic character. Furthermore, no significant difference between before and after PGE adsorption in oil quality was observed.

  20. Rural-urban differences in the long-term risk of colorectal cancer after adenoma removal: a population-based study.

    Science.gov (United States)

    Fournel, Isabelle; Cottet, Vanessa; Binquet, Christine; Jooste, Valérie; Faivre, Jean; Bouvier, Anne-Marie; Bonithon-Kopp, Claire

    2014-04-01

    We investigated the impact of municipality of residence on colonoscopic surveillance and colorectal cancer risk after adenoma resection in a French well-defined administrative area. This registry-based study included all patients residing in Côte d'Or (n=5769) first diagnosed with colorectal adenomas between January 1, 1990, and December 31, 1999. Information about colonoscopic surveillance and colorectal cancer incidence was collected until December 31, 2003. A rural place of residence reduced the probability of colonoscopic surveillance in men [HR=0.89 (95%CI: 0.79-0.99), p=0.041] and in patients without family history of colorectal cancer [HR=0.91(0.82-0.99), p=0.044]. After a median follow-up of 7.7 years, 87 patients developed invasive colorectal cancer. After advanced adenoma removal, the standardized incidence ratio for colorectal cancer was 3.03 (95%CI: 1.92-4.54) for rural patients and 1.87 (95%CI: 1.26-2.66) for urban patients compared with the general population. The risk of colorectal cancer was higher in rural patients than in urban ones only after removal of the initial advanced adenoma [HR=1.73 (95%CI: 1.01-3.00, p=0.048)]. Further adjustment for surveillance colonoscopy, physician location, and other confounders had little impact on these results. The increased risk of subsequent colorectal cancer after advanced adenoma removal in French rural patients was not explained by a lower rate of colonoscopic surveillance. The role of socio-economic and environmental factors requires further exploration. Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  1. Comprehensive analysis of step-feeding strategy to enhance biological nitrogen removal in alum sludge-based tidal flow constructed wetlands.

    Science.gov (United States)

    Hu, Y S; Zhao, Y Q; Zhao, X H; Kumar, J L G

    2012-05-01

    Step-feeding strategies have been extensively studied and comprehensively analyzed in this study for a four-stage alum sludge-based tidal flow constructed wetlands (AlS-TFCWs) system. Enhanced total nitrogen removal of 83% is achieved under high nitrogen loading rate of 19.1 g N/m(2)d. The key issues towards the success of a significant nitrogen removal in step-feeding TFCWs are the bed resting time (which provides better aeration for nitrification) and up flow stage/delayed input of side stream(s) (which ensure favorable environment for better denitrification). Simultaneous nitrification and denitrification (SND) was found effective in the 1st stage of the system and SND via nitrite is the main nitrogen conversion mechanism. The optimal influent distribution fraction for step-feeding purpose can be estimated from a theoretical basis, which is a function of the influent BCOD/TKN ratio. Therefore the influent distribution fraction should be adjusted according to the variety of influent characteristics, rather than a fixed value. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Artificial intelligence based model for optimization of COD removal efficiency of an up-flow anaerobic sludge blanket reactor in the saline wastewater treatment.

    Science.gov (United States)

    Picos-Benítez, Alain R; López-Hincapié, Juan D; Chávez-Ramírez, Abraham U; Rodríguez-García, Adrián

    2017-03-01

    The complex non-linear behavior presented in the biological treatment of wastewater requires an accurate model to predict the system performance. This study evaluates the effectiveness of an artificial intelligence (AI) model, based on the combination of artificial neural networks (ANNs) and genetic algorithms (GAs), to find the optimum performance of an up-flow anaerobic sludge blanket reactor (UASB) for saline wastewater treatment. Chemical oxygen demand (COD) removal was predicted using conductivity, organic loading rate (OLR) and temperature as input variables. The ANN model was built from experimental data and performance was assessed through the maximum mean absolute percentage error (= 9.226%) computed from the measured and model predicted values of the COD. Accordingly, the ANN model was used as a fitness function in a GA to find the best operational condition. In the worst case scenario (low energy requirements, high OLR usage and high salinity) this model guaranteed COD removal efficiency values above 70%. This result is consistent and was validated experimentally, confirming that this ANN-GA model can be used as a tool to achieve the best performance of a UASB reactor with the minimum requirement of energy for saline wastewater treatment.

  3. 42 CFR 413.220 - Methodology for calculating the per-treatment base rate under the ESRD prospective payment system...

    Science.gov (United States)

    2010-10-01

    ...; OPTIONAL PROSPECTIVELY DETERMINED PAYMENT RATES FOR SKILLED NURSING FACILITIES Payment for End-Stage Renal..., or 2009. CMS removes the effects of enrollment and price growth from total expenditures for 2007...

  4. A comparison of complication rates based on published haemovigilance data.

    Science.gov (United States)

    Flesland, O

    2007-06-01

    Haemovigilance is defined as the collection of information on complications of transfusion, the analysis of the data, and suggestions for improvement in the transfusion service. A national haemovigilance system is of value in identifying possible areas in need of improvement in the national transfusion system. Haemovigilance becomes even more important if the system is used to compare the situation in one country with the situation in other countries, e.g. if the countries differ significantly in products used. The current study focuses on immunological transfusion complications, especially TRALI, as published in haemovigilance reports from Denmark, Norway, Sweden and the UK. In Norway immunological transfusion reactions occurred 96.7 times per 100 000 red cell (RBC) transfusion, 231.1 times per 100 000 thrombocyte (Trc) concentrate transfusion and five times per 100.000 transfusions of solvent detergent treated plasma (SD plasma). Denmark and the UK have similar rates of transfusion reactions to RBC and fresh frozen plasma (FFP), but quite different for Trc (0.5 vs. 4.9 per 100 000). In 49% of reported TRALI the causative product is FFP, but no case of TRALI after SD plasma transfusion has been reported. When considering all reports for immunological complications in Norway, the most striking is the very small number of reports related to SD plasma. Comparing data from Denmark and the UK shows a big difference in reactions caused by thrombocyte concentrates that may reflect different production methods in the two countries. TRALI is most often caused by FFP, but has never been reported after SD plasma transfusion. Heamovigilance data can be valuable in choosing the safest products available.

  5. A Text Steganographic System Based on Word Length Entropy Rate

    Directory of Open Access Journals (Sweden)

    Francis Xavier Kofi Akotoye

    2017-10-01

    Full Text Available The widespread adoption of electronic distribution of material is accompanied by illicit copying and distribution. This is why individuals, businesses and governments have come to think of how to protect their work, prevent such illicit activities and trace the distribution of a document. It is in this context that a lot of attention is being focused on steganography. Implementing steganography in text document is not an easy undertaking considering the fact that text document has very few places in which to embed hidden data. Any minute change introduced to text objects can easily be noticed thus attracting attention from possible hackers. This study investigates the possibility of embedding data in text document by employing the entropy rate of the constituent characters of words not less than four characters long. The scheme was used to embed bits in text according to the alphabetic structure of the words, the respective characters were compared with their neighbouring characters and if the first character was alphabetically lower than the succeeding character according to their ASCII codes, a zero bit was embedded otherwise 1 was embedded after the characters had been transposed. Before embedding, the secret message was encrypted with a secret key to add a layer of security to the secret message to be embedded, and then a pseudorandom number was generated from the word counts of the text which was used to paint the starting point of the embedding process. The embedding capacity of the scheme was relatively high compared with the space encoding and semantic method.

  6. Haze Removal Based on a Fully Automated and Improved Haze Optimized Transformation for Landsat Imagery over Land

    Directory of Open Access Journals (Sweden)

    Lixin Sun

    2017-09-01

    Full Text Available Optical satellite imagery is often contaminated by the persistent presence of clouds and atmospheric haze. Without an effective method for removing this contamination, most optical remote sensing applications are less reliable. In this research, a methodology has been developed to fully automate and improve the Haze Optimized Transformation (HOT-based haze removal. The method is referred to as AutoHOT and characterized with three notable features: a fully automated HOT process, a novel HOT image post-processing tool and a class-based HOT radiometric adjustment method. The performances of AutoHOT in haze detection and compensation were evaluated through three experiments with one Landsat-5 TM, one Landsat-7 ETM+ and eight Landsat-8 OLI scenes that encompass diverse landscapes and atmospheric haze conditions. The first experiment confirms that AutoHOT is robust and effective for haze detection. The average overall, user’s and producer’s accuracies of AutoHOT in haze detection can reach 96.4%, 97.6% and 97.5%, respectively. The second and third experiments demonstrate that AutoHOT can not only accurately characterize the haze intensities but also improve dehazed results, especially for brighter targets, compared to traditional HOT radiometric adjustment.

  7. Gender bias in the diagnosis of personality disorders: the roles of base rates and social stereotypes.

    Science.gov (United States)

    Flanagan, Elizabeth H; Blashfield, Roger K

    2003-10-01

    In all three studies described in this article, novices were trained to associate traits from the DSM-IV Cluster B personality disorder categories with four letters of the alphabet. Novices were also taught various gender associations (i.e., "base rate" information) with the categories (none, stereotype-consistent, or stereotype-inconsistent). Results showed that when no gender associations were taught (Study I), case gender did not affect ratings of case vignettes. When associations were consistent with social stereotypes (Study II), case gender influenced ratings in the expected direction. When associations were the opposite of social stereotypes (Study III), only the ratings for narcissistic and histrionic were affected. Across the three studies, these results suggested that subjects rated cases in accordance with known "base rates," but that the correspondence between base rates and stereotypic associations affected the consistency and magnitude of this base rate effect.

  8. Chitosan and chitosan chlorhydrate based various approaches for enhancement of dissolution rate of carvedilol

    National Research Council Canada - National Science Library

    Shete, Amol S; Yadav, Adhikrao V; Murthy, Srinivasa M

    2012-01-01

    .... There is need to enhance the dissolution rate of carvedilol. The objective of our present investigation was to compare chitosan and chitosan chlorhydrate based various approaches for enhancement of dissolution rate of carvedilol...

  9. Removal of BCG artefact from concurrent fMRI-EEG recordings based on EMD and PCA.

    Science.gov (United States)

    Javed, Ehtasham; Faye, Ibrahima; Malik, Aamir Saeed; Abdullah, Jafri Malin

    2017-11-01

    Simultaneous electroencephalography (EEG) and functional magnetic resonance image (fMRI) acquisitions provide better insight into brain dynamics. Some artefacts due to simultaneous acquisition pose a threat to the quality of the data. One such problematic artefact is the ballistocardiogram (BCG) artefact. We developed a hybrid algorithm that combines features of empirical mode decomposition (EMD) with principal component analysis (PCA) to reduce the BCG artefact. The algorithm does not require extra electrocardiogram (ECG) or electrooculogram (EOG) recordings to extract the BCG artefact. The method was tested with both simulated and real EEG data of 11 participants. From the simulated data, the similarity index between the extracted BCG and the simulated BCG showed the effectiveness of the proposed method in BCG removal. On the other hand, real data were recorded with two conditions, i.e. resting state (eyes closed dataset) and task influenced (event-related potentials (ERPs) dataset). Using qualitative (visual inspection) and quantitative (similarity index, improved normalized power spectrum (INPS) ratio, power spectrum, sample entropy (SE)) evaluation parameters, the assessment results showed that the proposed method can efficiently reduce the BCG artefact while preserving the neuronal signals. Compared with conventional methods, namely, average artefact subtraction (AAS), optimal basis set (OBS) and combined independent component analysis and principal component analysis (ICA-PCA), the statistical analyses of the results showed that the proposed method has better performance, and the differences were significant for all quantitative parameters except for the power and sample entropy. The proposed method does not require any reference signal, prior information or assumption to extract the BCG artefact. It will be very useful in circumstances where the reference signal is not available. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Constraining earthquake source inversions with GPS data: 1. Resolution-based removal of artifacts

    Science.gov (United States)

    Page, M.T.; Custodio, S.; Archuleta, R.J.; Carlson, J.M.

    2009-01-01

    We present a resolution analysis of an inversion of GPS data from the 2004 Mw 6.0 Parkfield earthquake. This earthquake was recorded at thirteen 1-Hz GPS receivers, which provides for a truly coseismic data set that can be used to infer the static slip field. We find that the resolution of our inverted slip model is poor at depth and near the edges of the modeled fault plane that are far from GPS receivers. The spatial heterogeneity of the model resolution in the static field inversion leads to artifacts in poorly resolved areas of the fault plane. These artifacts look qualitatively similar to asperities commonly seen in the final slip models of earthquake source inversions, but in this inversion they are caused by a surplus of free parameters. The location of the artifacts depends on the station geometry and the assumed velocity structure. We demonstrate that a nonuniform gridding of model parameters on the fault can remove these artifacts from the inversion. We generate a nonuniform grid with a grid spacing that matches the local resolution length on the fault and show that it outperforms uniform grids, which either generate spurious structure in poorly resolved regions or lose recoverable information in well-resolved areas of the fault. In a synthetic test, the nonuniform grid correctly averages slip in poorly resolved areas of the fault while recovering small-scale structure near the surface. Finally, we present an inversion of the Parkfield GPS data set on the nonuniform grid and analyze the errors in the final model. Copyright 2009 by the American Geophysical Union.

  11. Optimization of a Nafion Membrane-Based System for Removal of Chloride and Fluoride from Lunar Regolith-Derived Water

    Science.gov (United States)

    Anthony, Stephen M.; Santiago-Maldonado, Edgardo; Captain, James G.; Pawate, Ashtamurthy S.; Kenis, Paul J. A.

    2012-01-01

    A long-term human presence in space will require self-sustaining systems capable of producing oxygen and potable water from extraterrestrial sources. Oxygen can be extracted from lunar regolith, and water contaminated with hydrochloric and hydrofluoric acids is produced as an intermediate in this process. We investigated the ability of Nafion proton exchange membranes to remove hydrochloric and hydrofluoric acids from water. The effect of membrane thickness, product stream flow rate, and acid solution temperature and concentration on water flux, acid rejection, and water and acid activity were studied. The conditions that maximized water transport and acid rejection while minimizing resource usage were determined by calculating a figure of merit. Water permeation is highest at high solution temperature and product stream flow rate across thin membranes, while chloride and fluoride permeation are lowest at low acid solution temperature and concentration across thin membranes. The figure of merit varies depending on the starting acid concentration; at low concentration, the figure of merit is highest across a thin membrane, while at high concentration, the figure of merit is highest at low solution temperature. In all cases, the figure of merit increases with increasing product stream flow rate.

  12. Albumin removal from human fibrinogen preparations for manufacturing human fibrin-based biomaterials

    Directory of Open Access Journals (Sweden)

    Vaibhav Sharma

    2015-01-01

    Full Text Available Commercially available two component human fibrin sealants are commonly used to manufacture human fibrin-based biomaterials. However, this method is costly and allows little room for further tuning of the biomaterial. Human fibrinogen solutions offer a more cost-effective and versatile alternative to manufacture human fibrin-based biomaterials. Yet, human fibrinogen is highly unstable and contains certain impurities like human albumin. Within the context of biomaterials and tissue engineering we offer a simple yet novel solution based on classical biochemical techniques to significantly reduce albumin in human fibrinogen solutions. This method can be used for various tissue engineering and biomedical applications as an initial step in the manufacturing of human fibrin-based biomaterials to optimise their regenerative application.

  13. Multiplicative noise removal through fractional order tv-based model and fast numerical schemes for its approximation

    Science.gov (United States)

    Ullah, Asmat; Chen, Wen; Khan, Mushtaq Ahmad

    2017-07-01

    This paper introduces a fractional order total variation (FOTV) based model with three different weights in the fractional order derivative definition for multiplicative noise removal purpose. The fractional-order Euler Lagrange equation which is a highly non-linear partial differential equation (PDE) is obtained by the minimization of the energy functional for image restoration. Two numerical schemes namely an iterative scheme based on the dual theory and majorization- minimization algorithm (MMA) are used. To improve the restoration results, we opt for an adaptive parameter selection procedure for the proposed model by applying the trial and error method. We report numerical simulations which show the validity and state of the art performance of the fractional-order model in visual improvement as well as an increase in the peak signal to noise ratio comparing to corresponding methods. Numerical experiments also demonstrate that MMAbased methodology is slightly better than that of an iterative scheme.

  14. Video-Based Physiologic Monitoring During an Acute Hypoxic Challenge: Heart Rate, Respiratory Rate, and Oxygen Saturation.

    Science.gov (United States)

    Addison, Paul S; Jacquel, Dominique; Foo, David M H; Antunes, André; Borg, Ulf R

    2017-09-01

    The physiologic information contained in the video photoplethysmogram is well documented. However, extracting this information during challenging conditions requires new analysis techniques to capture and process the video image streams to extract clinically useful physiologic parameters. We hypothesized that heart rate, respiratory rate, and oxygen saturation trending can be evaluated accurately from video information during acute hypoxia. Video footage was acquired from multiple desaturation episodes during a porcine model of acute hypoxia using a standard visible light camera. A novel in-house algorithm was used to extract photoplethysmographic cardiac pulse and respiratory information from the video image streams and process it to extract a continuously reported video-based heart rate (HRvid), respiratory rate (RRvid), and oxygen saturation (SvidO2). This information was then compared with HR and oxygen saturation references from commercial pulse oximetry and the known rate of respiration from the ventilator. Eighty-eight minutes of data were acquired during 16 hypoxic episodes in 8 animals. A linear mixed-effects regression showed excellent responses relative to a nonhypoxic reference signal with slopes of 0.976 (95% confidence interval [CI], 0.973-0.979) for HRvid; 1.135 (95% CI, 1.101-1.168) for RRvid, and 0.913 (95% CI, 0.905-0.920) for video-based oxygen saturation. These results were obtained while maintaining continuous uninterrupted vital sign monitoring for the entire study period. Video-based monitoring of HR, RR, and oxygen saturation may be performed with reasonable accuracy during acute hypoxic conditions in an anesthetized porcine hypoxia model using standard visible light camera equipment. However, the study was conducted during relatively low motion. A better understanding of the effect of motion and the effect of ambient light on the video photoplethysmogram may help refine this monitoring technology for use in the clinical environment.

  15. The surgical rate and recurrence rate in right colonic diverticulitis using the CT-based modified hinchey classification

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Hwan; Kim, Hyuk Jung; Jang, Suk Ki; Yeon, Jae Woo [Dept. of Radiology, Daejin Medical Center Bundang Jesaeng General Hospital, Seongnam (Korea, Republic of); Ko, You Sun; Lee, Kyoung Ho [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of)

    2015-08-15

    The purpose of this report is to retrospectively analyze the need for surgery, and the recurrence rate, using a CT-based method in patients with right colonic diverticulitis. For the purposes of our study, we included 416 patients with a mean age of 41.9 (238 of which were men), with a diagnosis of colonic diverticulitis that was based on CT findings. These findings were reviewed by two independent radiologists, who localized diverticulitis and determined it using a modified Hinchey classification. We were able to follow-up with 384 patients over a period of 30 months. Out of the 416 patients, 396 of them had right colonic diverticulitis. In right colonic diverticulitis, the κ value in determining the modified Hinchey classification was 0.80. 98.2% (389/396) of the patients with right colonic diverticulitis had stages Ia-II. The surgery rate was 4.6% (17/366) and 28% (5/18) for right and left colonic diverticulitis, respectively (p < 0.001). In the instances of right colonic diverticulitis, the surgery rate was 2.8% (10/359) for stages Ia-II, while all seven patients with stage III or IV underwent surgery. The recurrence rate was 6.5% (23/356) and 15% (2/13) for right and left colonic diverticulitis, respectively (p = 0.224). The CT-based modified Hinchey classification of right colonic diverticulitis showed good interobserver agreement. Most patients with right colonic diverticulitis had lower stages (Ia-II) at the point of CT, rarely needed surgery, and had a low recurrence rate.

  16. APE1, the DNA base excision repair protein, regulates the removal of platinum adducts in sensory neuronal cultures by NER

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun-Suk [Department of Biochemistry and Molecular Biology, Indianapolis, IN 46202 (United States); Guo, Chunlu; Thompson, Eric L. [Department of Pharmacology and Toxicology, Indianapolis, IN 46202 (United States); Jiang, Yanlin [Department of Pediatrics and Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46202 (United States); Kelley, Mark R. [Department of Biochemistry and Molecular Biology, Indianapolis, IN 46202 (United States); Department of Pharmacology and Toxicology, Indianapolis, IN 46202 (United States); Department of Pediatrics and Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46202 (United States); Vasko, Michael R. [Department of Pharmacology and Toxicology, Indianapolis, IN 46202 (United States); Lee, Suk-Hee, E-mail: slee@iu.edu [Department of Biochemistry and Molecular Biology, Indianapolis, IN 46202 (United States)

    2015-09-15

    Peripheral neuropathy is one of the major side effects of treatment with the anticancer drug, cisplatin. One proposed mechanism for this neurotoxicity is the formation of platinum adducts in sensory neurons that could contribute to DNA damage. Although this damage is largely repaired by nuclear excision repair (NER), our previous findings suggest that augmenting the base excision repair pathway (BER) by overexpressing the repair protein APE1 protects sensory neurons from cisplatin-induced neurotoxicity. The question remains whether APE1 contributes to the ability of the NER pathway to repair platinum-damage in neuronal cells. To examine this, we manipulated APE1 expression in sensory neuronal cultures and measured Pt-removal after exposure to cisplatin. When neuronal cultures were treated with increasing concentrations of cisplatin for two or three hours, there was a concentration-dependent increase in Pt-damage that peaked at four hours and returned to near baseline levels after 24 h. In cultures where APE1 expression was reduced by ∼80% using siRNA directed at APE1, there was a significant inhibition of Pt-removal over eight hours which was reversed by overexpressing APE1 using a lentiviral construct for human wtAPE1. Overexpressing a mutant APE1 (C65 APE1), which only has DNA repair activity, but not its other significant redox-signaling function, mimicked the effects of wtAPE1. Overexpressing DNA repair activity mutant APE1 (226 + 177APE1), with only redox activity was ineffective suggesting it is the DNA repair function of APE1 and not its redox-signaling, that restores the Pt-damage removal. Together, these data provide the first evidence that a critical BER enzyme, APE1, helps regulate the NER pathway in the repair of cisplatin damage in sensory neurons.

  17. Adherence to surveillance guidelines after removal of colorectal adenomas: a large, community-based study

    Science.gov (United States)

    van Heijningen, Else-Mariëtte B; Lansdorp-Vogelaar, Iris; Steyerberg, Ewout W; Goede, S Lucas; Dekker, Evelien; Lesterhuis, Wilco; ter Borg, Frank; Vecht, Juda; Spoelstra, Pieter; Engels, Leopold; Bolwerk, Clemens J M; Timmer, Robin; Kleibeuker, Jan H; Koornstra, Jan J; de Koning, Harry J; Kuipers, Ernst J; van Ballegooijen, Marjolein

    2015-01-01

    Objective To determine adherence to recommended surveillance intervals in clinical practice. Design 2997 successive patients with a first adenoma diagnosis (57% male, mean age 59 years) from 10 hospitals, who underwent colonoscopy between 1998 and 2002, were identified via Pathologisch Anatomisch Landelijk Geautomatiseerd Archief: Dutch Pathology Registry. Their medical records were reviewed until 1 December 2008. Time to and findings at first surveillance colonoscopy were assessed. A surveillance colonoscopy occurring within ±3 months of a 1-year recommended interval and ±6 months of a recommended interval of 2 years or longer was considered appropriate. The analysis was stratified by period per change in guideline (before 2002: 2–3 years for patients with 1 adenoma, annually otherwise; in 2002: 6 years for 1–2 adenomas, 3 years otherwise). We also assessed differences in adenoma and colorectal cancer recurrence rates by surveillance timing. Results Surveillance was inappropriate in 76% and 89% of patients diagnosed before 2002 and in 2002, respectively. Patients eligible under the pre-2002 guideline mainly received surveillance too late or were absent (57% of cases). For patients eligible under the 2002 guideline surveillance occurred mainly too early (48%). The rate of advanced neoplasia at surveillance was higher in patients with delayed surveillance compared with those with too early or appropriate timed surveillance (8% vs 4–5%, p<0.01). Conclusions There is much room for improving surveillance practice. Less than 25% of patients with adenoma receive appropriate surveillance. Such practice seriously hampers the effectiveness and efficiency of surveillance, as too early surveillance poses a considerable burden on available resources while delayed surveillance is associated with an increased rate of advanced adenoma and especially colorectal cancer. PMID:25586057

  18. Duration of off-loading and recurrence rate in Charcot osteo-arthropathy treated with less restrictive regimen with removable walker.

    Science.gov (United States)

    Christensen, Tomas M; Gade-Rasmussen, Birthe; Pedersen, Lis W; Hommel, Eva; Holstein, Per E; Svendsen, Ole L

    2012-01-01

    Recent literature on acute diabetic Charcot osteoarthropathy (CA) reports unusually long periods of off-loading. Data suggest that this might increase the re-currence rate. Subsequently we evaluated the influence of duration of off-loading on the risk of required re-casting. In this retrospective consecutive series from 2000 to 2005, 56 people with diabetes and an acute Charcot foot were included. The inclusion criteria were an initial persistent temperature difference more than 2°C between the two feet, oedema, and typical hot spots on a bone scintigram, radiology, and a typical clinical course. Treatment was off-loading in a removable cast and 2 crutches. In-door walking was allowed. Gradually augmented weight bearing was prescribed when the skin temperature difference had decreased to a level less than 2°C and edema had subsided. Re-casting was required for immediate exacerbation during re-load as well as for recurrence - defined as new swelling and skin temperature difference of more than 2°C in the same foot occurring after a stable interval of at least one month after full weight bearing. The duration of off-loading for all patients was 141±21 days (mean±SD). Three patients (5%) were re-casted immediately for exacerbation after re-load and 7 patients (12 %) after recurrence of the CA. Duration of re-casting was 79±44 days. The primary period of off-loading was not statistically significantly different for those not requiring versus those requiring re-casting: 142±24 days compared to 134±41 days. Neither were the differences in demographic data, metabolic regulation, BMI or localization of CA. Patients with risk of exacerbation or recurrence of CA could not be identified in the present study and there was no relation to the duration of off-loading. Nevertheless off-loading periods with immobilisation should be kept as short as possible, due to other side effects. This can be obtained by early gradual augmented re-loading. Copyright © 2012 Elsevier Inc

  19. Magnetic graphene oxide based nano-composites for removal of radionuclides and metals from contaminated solutions.

    Science.gov (United States)

    Lujanienė, G; Šemčuk, S; Lečinskytė, A; Kulakauskaitė, I; Mažeika, K; Valiulis, D; Pakštas, V; Skapas, M; Tumėnas, S

    2017-01-01

    Magnetic graphene oxide based composites of the nano-particle size of nano-composites was studied in a wide range of initial concentrations and analyzed by Langmuir and Freundlich models. In addition, the effects of pH and coexisting ions on the adsorption of Cs to Prussian blue based composites were investigated. The maximum adsorption capacities of studied elements varied from 29 to 641 mg g(-1). The obtained Langmuir and Freundlich constants indicated the dominating physisorption mechanism and favorable adsorption conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. A fuzzy-logic based diagnosis and control of a reactor performing complete autotrophic nitrogen removal

    DEFF Research Database (Denmark)

    Mauricio Iglesias, Miguel; Vangsgaard, Anna Katrine; Gernaey, Krist

    Diagnosis and control modules based on fuzzy set theory were tested for novel bioreactor monitoring and control. Two independent modules were used jointly to carry out first the diagnosis of the state of the system and then use transfer this information to control the reactor. The separation...

  1. A fuzzy-logic based diagnosis and control of a reactor performing complete autotrophic nitrogen removal

    DEFF Research Database (Denmark)

    Mauricio Iglesias, Miguel; Vangsgaard, Anna Katrine; Gernaey, Krist

    2013-01-01

    This contribution explores the use of diagnosis and control modules based on fuzzy set theory and logic for bioreactor monitoring and control. With this aim, two independent modules were used jointly to carry out first the diagnosis of the state of the system and then use transfer this information...

  2. Subsurface iron and arsenic removal: Low-cost technology for community-based water supply in Bangladesh

    KAUST Repository

    Van Halem, Doris

    2010-12-01

    The principle of subsurface or in situ iron and arsenic removal is that aerated water is periodically injected into an anoxic aquifer through a tube well, displacing groundwater containing Fe(II). An oxidation zone is created around the tube well where Fe(II) is oxidised. The freshly formed iron hydroxide surfaces provide new sorption sites for soluble Fe(II) andarsenic. The system\\'s efficiency is determined based on the ratio between abstracted volume with reduced iron/arsenic concentrations (V) and the injected volume (Vi). In the field studypresented in this paper, the small-scale application of this technology was investigated in rural Bangladesh. It was found that at small injection volumes (>1m3) iron removal was successful and became more effective with every successive cycle. For arsenic, however, the system did not prove to be very effective yet. Arsenic retardation was only limited and breakthrough of 10mg/L (WHO guideline) was observed before V/Vi = 1, which corresponds to arrival of groundwater at the well. Possible explanations for insufficient arsenic adsorption are the short contact times within the oxidation zone, and the presence of competing anions, like phosphate. © IWA Publishing 2010.

  3. Development, verification and validation of an FPGA-based core heat removal protection system for a PWR

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Yichun, E-mail: ycwu@xmu.edu.cn [College of Energy, Xiamen University, Xiamen 361102 (China); Shui, Xuanxuan, E-mail: 807001564@qq.com [College of Energy, Xiamen University, Xiamen 361102 (China); Cai, Yuanfeng, E-mail: 1056303902@qq.com [College of Energy, Xiamen University, Xiamen 361102 (China); Zhou, Junyi, E-mail: 1032133755@qq.com [College of Energy, Xiamen University, Xiamen 361102 (China); Wu, Zhiqiang, E-mail: npic_wu@126.com [State Key Laboratory of Reactor System Design Technology, Nuclear Power Institute of China, Chengdu 610041 (China); Zheng, Jianxiang, E-mail: zwu@xmu.edu.cn [College of Energy, Xiamen University, Xiamen 361102 (China)

    2016-05-15

    Highlights: • An example on life cycle development process and V&V on FPGA-based I&C is presented. • Software standards and guidelines are used in FPGA-based NPP I&C system logic V&V. • Diversified FPGA design and verification languages and tools are utilized. • An NPP operation principle simulator is used to simulate operation scenarios. - Abstract: To reach high confidence and ensure reliability of nuclear FPGA-based safety system, life cycle processes of discipline specification and implementation of design as well as regulations verification and validation (V&V) are needed. A specific example on how to conduct life cycle development process and V&V on FPGA-based core heat removal (CHR) protection system for CPR1000 pressure water reactor (PWR) is presented in this paper. Using the existing standards and guidelines for life cycle development and V&V, a simplified FPGA-based CHR protection system for PWR has been designed, implemented, verified and validated. Diversified verification and simulation languages and tools are used by the independent design team and the V&V team. In the system acceptance testing V&V phase, a CPR1000 NPP operation principle simulator (OPS) model is utilized to simulate normal and abnormal operation scenarios, and provide input data to the under-test FPGA-based CHR protection system and a verified C code CHR function module. The evaluation results are applied to validate the under-test FPGA-based CHR protection system. The OPS model operation outputs also provide reasonable references for the tests. Using an OPS model in the system acceptance testing V&V is cost-effective and high-efficient. A dedicated OPS, as a commercial-off-the-shelf (COTS) item, would contribute as an important tool in the V&V process of NPP I&C systems, including FPGA-based and microprocessor-based systems.

  4. BIM-Based Decision Support System for Material Selection Based on Supplier Rating

    Directory of Open Access Journals (Sweden)

    Abiola Akanmu

    2015-12-01

    Full Text Available Material selection is a delicate process, typically hinged on a number of factors which can be either cost or environmental related. This process becomes more complicated when designers are faced with several material options of building elements and each option can be supplied by different suppliers whose selection criteria may affect the budgetary and environmental requirements of the project. This paper presents the development of a decision support system based on the integration of building information models, a modified harmony search algorithm and supplier performance rating. The system is capable of producing the cost and environmental implications of different material combinations or building designs. A case study is presented to illustrate the functionality of the developed system.

  5. Development of Composite Adsorbent Coating Based Acrylic Polymer/Bentonite for Methylene Blue Removal

    OpenAIRE

    Azha, Syahida Farhan; Abd Hamid, Shazlina; Ismail, Suzylawati

    2017-01-01

    The development of composite adsorbent coating based acrylic polymer solution (APS) mixed with bentonite (ben) was investigated. The composite adsorbent coating was prepared and coated to a high surface area substrate, cotton cellulosic fiber (CCF). The APS/ben-CCF was used for a single cationic methylene blue (MB) dye adsorption system. Characterization of composition and structure of materials and coating was carried out by X-ray fluorescence (XRF), scanning electron microscopy (SEM), and U...

  6. Effects of Personalization and Invitation Email Length on Web-Based Survey Response Rates

    Science.gov (United States)

    Trespalacios, Jesús H.; Perkins, Ross A.

    2016-01-01

    Individual strategies to increase response rate and survey completion have been extensively researched. Recently, efforts have been made to investigate a combination of interventions to yield better response rates for web-based surveys. This study examined the effects of four different survey invitation conditions on response rate. From a large…

  7. A rate-compatible family of protograph-based LDPC codes built by expurgation and lengthening

    Science.gov (United States)

    Dolinar, Sam

    2005-01-01

    We construct a protograph-based rate-compatible family of low-density parity-check codes that cover a very wide range of rates from 1/2 to 16/17, perform within about 0.5 dB of their capacity limits for all rates, and can be decoded conveniently and efficiently with a common hardware implementation.

  8. Zirconium oxide-coated sand based batch and column adsorptive removal of arsenic from water: Isotherm, kinetic and thermodynamic studies

    Directory of Open Access Journals (Sweden)

    Saif Ali Chaudhry

    2017-06-01

    Full Text Available This paper reports zirconium oxide-coated sand preparation, characterization by SEM, EDX, XRD, FT-IR and thermoanalytical techniques, and use as an adsorbent for the removal of most toxic form of arsenic, As(III, from aqueous solution in both batch and column methods. Batch experimental parameters such as contact time, concentration, dose of adsorbent, pH of As(III solution and temperature were optimized. The adsorption data was fitted to Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms at 303, 308 and 313 K. The maximum Langmuir monolayer adsorption capacity was found to be 136.98 μg/g at 313 K. Values of ΔH°, ΔG° and ΔS° were found to be −12.90, −8.74 to –8.28 and 0.014 kJ/mol, suggesting exothermic and spontaneous adsorption process with slight increase in entropy. The adsorption process followed pseudo-second order kinetics and was controlled by film diffusion step. The column studies showed that when flow rate was increased from 3.0 to 5.0 mL/min, the arsenic adsorption capacity of ZrOCS increased from 33.104 to 42.231 μg/g and breakthrough, and exhaustion times got reduced reduced. The results indicated that zirconium oxide-coated sand (ZrOCS is an excellent adsorbent for the removal of As(III from water.

  9. Technical bases and user's manual for the prototype of a Suppression Pool Aerosol Removal Code (SPARC)

    Energy Technology Data Exchange (ETDEWEB)

    Owczarski, P.C.; Schreck, R.I.; Postma, A.K.

    1985-05-01

    This code was written to calculate the capture of aerosol particles in the pressure suppression pool (wet well) of a boiling water reactor under hypothetical accident conditions. The code incorporates five aerosol scrubbing models and two thermal-hydraulic models. The scrubbing models describe (1) steam condensation, (2) soluble particle growth in a humid atmosphere, (3) gravitational settling, (4) inertial deposition, (5) diffusional deposition. Mechanical entrainment of pool liquid by breaking of bubbles at the surface was also considered. An optional model for equilibrium pool temperature and a model for steam evaporation are the two thermal-hydraulic models used in the code. Steam evaporation was found to significantly retard deposition processes in pools near the boiling point. The code user supplies the values of several controlling variables in the code input. The SPARC output can include the decontamination factors (DF) of twenty different particle size groups, an overall DF for the whole particle distribution, particle log normal distribution parameters, and mass flow rates of particles (wet and dry) leaving the pool.

  10. Magnetic composites based on natural sources used for removal of oil; Compositos magneticos baseados em fontes naturais usados para remocao de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Grance, E.G.O.; Varela, A.; Daher, E.; Gomes, L.Q.; Michel, R.C.; Souza Junior, F.G. [Instituto de Macromoleculas Professora Eloisa Mano - Universidade Federal do Rio de Janeiro, RJ (Brazil)], e-mail: fernando_gomes@ima.ufrj.br; Rodrigues, C.H.M. [Coordenadoria da Licenciatura em Quimica. Instituto Federal do Espirito Santo, Aracruz, ES (Brazil); Oliveira, G.E. [Departamento de Quimica - Centro de Ciencias Exatas - Universidade Federal do Espirito Santo (UFES), Vitoria, ES (Brazil)

    2011-07-01

    Present paper deals with the preparation and characterization of a magnetic resin based on lignin from Kraft process. This material, due to this aromatic / aliphatic balance is able to oil spill clean up processes. The resin was prepared through bulk polycondensation of lignin, cashew nutshell liquid and formaldehyde in presence of maghemite nanoparticles. Obtained magnetic composites were studied using ATR, FTIR and SAXS. Magnetic force and oil removal capability tests were also performed. Results showed that obtained materials posses a considerable magnetic force and a good oil removal capability. One part of the best material was able to remove eleven parts of oil from the water, making it a good absorber. (author)

  11. Kurtosis based blind source extraction of complex noncircular signals with application in EEG artifact removal in real-time

    Directory of Open Access Journals (Sweden)

    Soroush eJavidi

    2011-10-01

    Full Text Available A new class of complex domain blind source extraction (BSE algorithms suitable for the extraction of both circular and noncircular complex signals is proposed. This is achieved through sequential extraction based on the degree of kurtosis and in the presence of noncircular measurement noise. The existence and uniqueness analysis of the solution is followed by a study of fast converging variants of the algorithm. The performance is first assessed through simulations on well understood benchmark signals, followed by a case study on real-time artifact removal from EEG signals, verified using both qualitative and quantitative metrics. The results illustrate the power of the proposed approach in real-time blind extraction of general complex-valued sources.

  12. The effect of COD loading on the granule-based enhanced biological phosphorus removal system and the recoverability.

    Science.gov (United States)

    Yu, Shenjing; Sun, Peide; Zheng, Wei; Chen, Lujun; Zheng, Xiongliu; Han, Jingyi; Yan, Tao

    2014-11-01

    In this study, the effect of varied COD loading (200, 400, 500, 600 and 800 mg L(-1)) on stability and recoverability of granule-based enhanced biological phosphorus removal (EBPR) system was investigated during continuously 53-d operation. Results showed that COD loading higher than 500 mg L(-1) could obviously deteriorate the granular EBPR system and result in sludge bulking with filamentous bacteria. High COD loading also changed the transformation patterns of poly-β-hydroxyalkanoates (PHAs) and glycogen in metabolism process of polyphosphate-accumulating organisms (PAOs) and inhibited the EPS secretion, which completely destroyed the stability and integrality of granules. Results of FISH indicated that glycogen-accumulating organisms (GAOs) and other microorganisms had a competitive advantage over PAOs with higher COD loading. The community composition and EBPR performance were recovered irreversibly in long time operation when COD loading was higher than 500 mg L(-1). Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Zinc Ion Removal on Hybrid Pectin-Based Beads Containing Modified Poly(Methyl Methacrylate Waste

    Directory of Open Access Journals (Sweden)

    Agata Jakóbik-Kolon

    2017-12-01

    Full Text Available A new hybrid sorbent in the form of round beads containing modified poly(methyl methacrylate (PMMA waste immobilized in pectin and crosslinked with calcium ions was prepared. A previously obtained and characterized powdered poly(methyl methacrylate–based sorbent was used. Batch and column studies on the new material’s sorption-desorption properties were performed. Two kinetic models (pseudo-first- and pseudo-second-order and three isotherms (Langmuir, Langmuir bisite and Freundlich were used to describe the results. Breakthrough and elution curves were also obtained. Nitric, hydrochloric, and sulfuric acid of various concentrations were used in the desorption studies. Higher sorption affinity of zinc(II ions to hybrid sorbent than to pectin alone, reflected by higher values of the Langmuir and Freundlich model parameters, was observed. The maximum sorption capacities, calculated based on the best-fitted models, were 50.2 mg/g (Langmuir bisite and 42.2 mg/g (Langmuir for hybrid and only pectin beads, respectively. The stripping of Zn ions using 0.1 M solutions of mineral acids was similarly effective in the case of both sorbents. The mass balance calculated for the column studies showed about 100% recovery of zinc in a sorption-desorption cycle. By applying the hybrid sorbent under the studied conditions it is possible to purify Zn in water to the level permitted by law and concentrate Zn(II ions by about 60 times.

  14. Novel Approach to Tar Removal from Biomass Producer Gas by Means of a Nickel-Based Catalyst

    Science.gov (United States)

    Vosecký, M.; Kameníková, P.; Pohořelý, M.; Skoblja, S.; Punčochář, M.

    The nickel-based catalyst was exposed to the raw gas from gasification of woody biomass with air in a fluidized-bed. After dust removal on a barrier filter and sulphur compounds capture, namely H2S, on an active sorbent made of CuO and ZnO, higher hydrocarbons as tar components were decomposed/reformed on aNi-catalyst. Steam reforming reactions led to decomposition of tar and all hydrocarbons higher than CH4 into mainly H2 and CO which further underwent reaction with steam via the water gas shift reaction to CO2. The reforming reactions caused approximately 10-20 % decrease in the lower heating values of the producer gas from the inlet values 5.0-6.5 MJ m-3. The gas yield increased fromvalues 2.4-2.6 m3 kg-1 to values 2.8-3.0 m3 kg-1 on dry biomass basis. The chosen tar removal concept based on combination of dolomite in the fluidized-bed with the secondary catalytic reactor was proved by 20 hours long experiment in which the finaltar content below 30 mg m-3 was attained corresponding to more than 97 % tar conversion. H2S content in producer gas was expected to be below 100 vol. ppm, bulk of which was captured on the sorbent. Only limited deactivation of thecatalyst by sulphur compounds was found in the front of the catalyst bed where sulphur content was determined as high as 173 wt. ppm compared to 22 wt. ppm in the fresh sample.

  15. 78 FR 75560 - Biofuels Washington LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Science.gov (United States)

    2013-12-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Biofuels Washington LLC; Supplemental Notice That Initial Market- Based Rate...-referenced proceeding, of Biofuels Washington LLC's application for market-based rate authority, with an...

  16. Can Sample-Specific Simulations Help Detect Low Base-Rate Taxonicity?

    Science.gov (United States)

    Beach, Steven R. H.; Amir, Nader; Bau, Jinn Jonp

    2005-01-01

    The authors examined the role of the sample-specific simulations (SSS; A. M. Ruscio & J. Ruscio, 2002; J. Ruscio & A. M. Ruscio, 2004) procedure in detecting low base-rate taxa that might otherwise prove elusive. The procedure preserved key distributional characteristics for moderate to high base-rate taxa, but it performed inadequately for low…

  17. 77 FR 35374 - Independence Electricity; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Science.gov (United States)

    2012-06-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Independence Electricity; Supplemental Notice That Initial Market-Based Rate...-referenced proceeding of Independence Electricity's application for market-based rate authority, with an...

  18. 75 FR 61747 - Union Leader Corporation; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Science.gov (United States)

    2010-10-06

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Union Leader Corporation; Supplemental Notice That Initial Market-Based Rate... notice in the above-referenced proceeding of Union Leader Corporation's application for market-based rate...

  19. Influence of category coherence and type of base-rate acquisition on property generalization.

    Science.gov (United States)

    Kim, ShinWoo; Lee, Guk-Hee

    2017-01-01

    Category coherence involves identifying similarities between social categories, such as jobs and hobbies, and is primarily used for generalizing or drawing inferences about their properties. Category coherence is also used for drawing inferences from explicit information, such as base rates. For example, people generalize the properties of groups or brands from multiple sources (e.g., survey results and the share market in periodicals). However, generalizing the properties of categories using explicit base-rate information may not always involve category coherence; rather, it may involve directly analyzing base-rate information. Therefore, this study attempts to distinguish between conditions in which people use category coherence and explicit base-rate information. Specifically, we proposed that people acquiring explicit base-rate knowledge-described as a percentage-would generalize a category's properties according to its base rate; however, for base-rate information acquired via direct observation, the inductive strength in generalizing properties would be greater for categories with high levels of coherence. Our results (Experiment 1 and Experiment 2) validated these two predictions. Finally, the interaction between category coherence and type of base-rate acquisition was discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Unobtrusive heart rate monitor based on a fiber specklegram sensor and a single-board computer

    Science.gov (United States)

    Benevides, Alessandro B.; Frizera, Anselmo; Cotrina, Anibal; Ribeiro, Moisés. R. N.; Segatto, Marcelo E. V.; Pontes, Maria José

    2015-09-01

    This paper proposes a portable and unobtrusive heart rate monitor based on fiber specklegram sensors. The proposed module uses the Raspberry Pi module to perform the image acquisition and the fiber specklegram sensor, which is based on multimode plastic optical fibers. The heart rate is obtained by welch power spectral density estimate and the heart beats are identified by means of a threshold analysis.

  1. TEMPORARY REMOVAL

    DEFF Research Database (Denmark)

    Calkins, Hugh; Hindricks, Gerhard; Cappato, Riccardo

    2017-01-01

    The publisher regrets that this article has been temporarily removed. A replacement will appear as soon as possible in which the reason for the removal of the article will be specified, or the article will be reinstated. The full Elsevier Policy on Article Withdrawal can be found at https://www.e...

  2. Multilevel correlations in the biological phosphorus removal process: From bacterial enrichment to conductivity-based metabolic batch tests and polyphosphatase assays.

    Science.gov (United States)

    Weissbrodt, David G; Maillard, Julien; Brovelli, Alessandro; Chabrelie, Alexandre; May, Jonathan; Holliger, Christof

    2014-12-01

    Enhanced biological phosphorus removal (EBPR) from wastewater relies on the preferential selection of active polyphosphate-accumulating organisms (PAO) in the underlying bacterial community continuum. Efficient management of the bacterial resource requires understanding of population dynamics as well as availability of bioanalytical methods for rapid and regular assessment of relative abundances of active PAOs and their glycogen-accumulating competitors (GAO). A systems approach was adopted here toward the investigation of multilevel correlations from the EBPR bioprocess to the bacterial community, metabolic, and enzymatic levels. Two anaerobic-aerobic sequencing-batch reactors were operated to enrich activated sludge in PAOs and GAOs affiliating with "Candidati Accumulibacter and Competibacter phosphates", respectively. Bacterial selection was optimized by dynamic control of the organic loading rate and the anaerobic contact time. The distinct core bacteriomes mainly comprised populations related to the classes Betaproteobacteria, Cytophagia, and Chloroflexi in the PAO enrichment and of Gammaproteobacteria, Alphaproteobacteria, Acidobacteria, and Sphingobacteria in the GAO enrichment. An anaerobic metabolic batch test based on electrical conductivity evolution and a polyphosphatase enzymatic assay were developed for rapid and low-cost assessment of the active PAO fraction and dephosphatation potential of activated sludge. Linear correlations were obtained between the PAO fraction, biomass specific rate of conductivity increase under anaerobic conditions, and polyphosphate-hydrolyzing activity of PAO/GAO mixtures. The correlations between PAO/GAO ratios, metabolic activities, and conductivity profiles were confirmed by simulations with a mathematical model developed in the aqueous geochemistry software PHREEQC. © 2014 Wiley Periodicals, Inc.

  3. Removing damped sinusoidal vibrations in adaptive optics systems using a DFT-based estimation method

    Science.gov (United States)

    Kania, Dariusz

    2017-06-01

    The problem of a vibrations rejection in adaptive optics systems is still present in publications. These undesirable signals emerge because of shaking the system structure, the tracking process, etc., and they usually are damped sinusoidal signals. There are some mechanical solutions to reduce the signals but they are not very effective. One of software solutions are very popular adaptive methods. An AVC (Adaptive Vibration Cancellation) method has been presented and developed in recent years. The method is based on the estimation of three vibrations parameters and values of frequency, amplitude and phase are essential to produce and adjust a proper signal to reduce or eliminate vibrations signals. This paper presents a fast (below 10 ms) and accurate estimation method of frequency, amplitude and phase of a multifrequency signal that can be used in the AVC method to increase the AO system performance. The method accuracy depends on several parameters: CiR - number of signal periods in a measurement window, N - number of samples in the FFT procedure, H - time window order, SNR, THD, b - number of A/D converter bits in a real time system, γ - the damping ratio of the tested signal, φ - the phase of the tested signal. Systematic errors increase when N, CiR, H decrease and when γ increases. The value of systematic error for γ = 0.1%, CiR = 1.1 and N = 32 is approximately 10^-4 Hz/Hz. This paper focuses on systematic errors of and effect of the signal phase and values of γ on the results.

  4. Investigation of Ammonium and Nitrite Removal by Zeolite Material Synthesized on Red Mud Base

    Directory of Open Access Journals (Sweden)

    Pham Thi Mai Huong

    2017-07-01

    Full Text Available The zeolite with the unit formula of Na8(Al6Si6O24S.4H2O was synthesized directly on red mud base with addition of single silicon (signed as RH-ZeO-Si and both silicon and aluminum portions (signed as RM-ZeO-SiAl to original Tan Rai (Vietnam red mud. The structure of the zeolite was studied by X-Ray difration and FT-IR absorption spectra. The synthesized materials were studied on their adsorption ability of ammonium and nitrite ions. The results showed that, the adsorption of ammonium cation was mostly allowing ion-exchange mechanism and the zeolite crystaline forms played predominantly role besids minor one of single metal oxides. For nitrite anions, it is otherwise, the adsorption mechanism was mostly leant to electrostatic attraction between nitrite anions and electropositive effect of the hematite surface in light acidic condition. The adsorption isotherms of all ammonium and nitrite ions on both synthesized materials were nearly conformable with Freundlich model than Langmuir model. Those showed that, both materials have unhomogeneous adsorption surface. The maximum adsorption capacity of ammonium and nitrite on RM-ZeO-Si was 5.71 mg/g and 2.73 mg/g respectively, and on RM-ZeO-SiAl was 5.61 mg/g and 3.12 mg/g respectively. The initial test of competitive ions influencing on adsorption ability showed that, for all cases the competition of cations to ammonium ion was more significance than those of anions to nitrite ion in the same conditions.

  5. Multiplicative Noise and Blur Removal by Framelet Decomposition and and $l_1$-based L-curve Method.

    Science.gov (United States)

    Ng, Michael; Zhao, Xi-Le; Wang, Fan

    2016-06-22

    This paper proposes a framelet based convex optimization model for multiplicative noise and blur removal problem. The main idea is to employ framelet expansion to represent the original image and use the variable decomposition to solve the problem. Because of the nature of multiplicative noise, we decompose the observed data into the original image variable and the noise variable to obtain the resulting model. The original image variable is represented by framelet, it is determined by using l1-norm in the selection and shrinkage of framelet coefficients. The noise variable is measured by using the mean and the variance of the underlying probability distribution. This framelet setting can be applied to analysis, synthesis and balanced approaches, and the resulting optimization models are convex such that they can be solved very efficiently by the alternating direction of multiplier method. An another contribution of this paper is to propose to select the regularization parameter by using the l1-based L-curve method for these framelet based models. Numerical examples are presented to illustrate the effectiveness of these models and show that the performance of the proposed method is better than that by the existing methods.

  6. INVESTIGATION OF THE NON THERMAL PLASMA-BASED ADVANCED OXIDATION PROCESS FOR REMOVAL OF ORGANIC CONTAMINANTS IN AZO DYES SOLUTION

    Directory of Open Access Journals (Sweden)

    Tota Pirdo Kasih

    2017-03-01

    Full Text Available The present study deals with the development of non thermal plasma-based AOPs for removal of organic contaminants in wastewater treatment. The plasma itself is generated based on point-to-point geometry under organic solution and can generate hydroxyl radicals, ozone, peroxide and other radicals as the basic species to destruct organic contaminants. Electrical diagnostic in the form of voltage and current waveform was investigated through the variation of time during the formation of plasma channeling. The evolutions of plasma channeling with its physical phenomena were also discussed. The relationship between the electrodes distance towards applied voltage to sustain the plasma were also studied. It was found that the mineralization have occurred during plasma treatment to transform the harmful functional group in organic dye solution into harmless species. Simultaneously, the decoloration process by using this submerged plasma treatment system is able to change the orange color of methyl orange solution into clearly transparent water in 30 minutes. The present findings may provide the plasma-based advanced oxidation process as a promising chemical-free and cost competitive AOP process application on specially the waste water treatment in textile industry.

  7. Enhanced Detection of Vibrio Cholerae in Oyster Homogenate Based on Centrifugal Removal of Inhibitory Agents

    Science.gov (United States)

    Alexander, Donita; DePaola, Angelo; Young, Ronald B.

    1998-01-01

    The disease cholera, caused by Vibrio cholerae, has been associated with consumption of contaminated seafood, including raw oysters. Detection of V. cholerae in foods typically involves blending the oysters, diluting the homogenate in alkaline peptone water (APW), overnight enrichment, and isolation on selective agar. Unfortunately, the oyster homogenate must be diluted to large volumes because lower dilutions inhibit the growth of V. cholerae. The goals of this study were to develop an alternative to large dilutions and to evaluate the basis for the inhibition observed in lower dilutions of oyster homogenates. Centrifugation of oyster homogenates at 10,000 x g for 15 min, followed by enrichment of the resulting pellet in APW, was found to eliminate the inhibition of V. cholerae growth. Inhibition appears not to be due to competing microflora but to a component(s) released when V. cholerae grows in the presence of oyster homogenate. The inhibitory component(s) kills the V. cholerae after the cell concentration reaches > 10(exp 8) cells/mL, rather than initially preventing their growth. The pH also declines from 8.0 to 5.5 during this period; however, the pH decline by itself appears not to cause V. cholerae death. Seven strains of V. cholerae (01 and non-01) and two strains of V. vulnificus were susceptible to the inhibitory agent(s). However, other Vibrio and non-Vibrio species tested were not inhibited by the oyster homogenates. Based on digestion of oyster homogenates with pronase, trypsin and lipase, the inhibitory reaction involves a protein(s). In a preliminary trial with oyster homogenate seeded with 1 cfu/g of V. cholerae, the modified centrifugation technique detected a slightly higher percentage of samples at a 1:10 dilution than the standard FDA Bacteriological Analytical Method (BAM) detected in uncentrifuged oyster homogenate at a 1:100 dilution. V. cholerae in seeded samples could also be detected more frequently by the modified centrifugation method

  8. Removal of Basic Dyes from Aqueous Solution by Chloroacetic Acid Modified Ferula Communis Based Adsorbent: Thermodynamic and Kinetic Studies

    OpenAIRE

    Salih, Shameran Jamal

    2014-01-01

    ABSTRACT: This research aimed to propose an alternative cheap and abundantly available adsorbent (Ferula communis) for the removal of basic dyes from aqueous solutions. Chloroacetic acid modified Ferula communis (MFC) shows a great potential for the removal of basic red 9 dyes (BR9) from aqueous solution with the effects of solution capacity under pH, temperature, contact time, adsorbent dosage, and initial dye concentration condition on BR9 removal were examined. The adsorption equilibrium d...

  9. Effect of calcium on adsorptive removal of As(III) and As(V) by iron oxide-based adsorbents

    KAUST Repository

    Uwamariya, V.

    2014-06-25

    The effects of calcium on the equilibrium adsorption capacity of As(III) and As(V) onto iron oxide-coated sand (IOCS) and granular ferric hydroxide (GFH) were investigated through batch experiments, rapid small-scale column tests (RSSCT) and kinetics modelling. Batch experiments showed that at calcium concentrations≤20 mg/L, high As(III) and As(V) removal efficiencies by IOCS and GFH are achieved at pH 6. An increase of the calcium concentration to 40 and 80 mg/L reversed this trend, giving higher removal efficiencies at higher pH (8). The adsorption capacities of IOCS and GFH at an equilibrium arsenic concentration of 10 g/L were found to be between 2.0 and 3.1 mg/g for synthetic water without calcium and between 2.8 and 5.3 mg/g when 80 mg/L of calcium was present at the studied pH values. After 10 hours of filter run in RSSCT, approximately 1000 empty bed volumes, the ratios of C/Co for As(V) were 26% and 18% for calcium-free model water; and only 1% and 0.2% after addition of 80 mg/L of Ca for filter columns with IOCS and GFH, respectively. The adsorption of As(III) and As(V) onto GFH follows a second-order reaction, with and without addition of calcium. The adsorption of As(III) and As(V) onto IOCS follows a first-order reaction without calcium addition, and moves to the second-reaction-order kinetics when calcium is added. Based on the intraparticle diffusion model, the main controlling mechanism for As(III) adsorption is intraparticle diffusion, while surface diffusion contributes greatly to the adsorption of As(V).

  10. Acid-base chemical reaction model for nucleation rates in the polluted atmospheric boundary layer.

    Science.gov (United States)

    Chen, Modi; Titcombe, Mari; Jiang, Jingkun; Jen, Coty; Kuang, Chongai; Fischer, Marc L; Eisele, Fred L; Siepmann, J Ilja; Hanson, David R; Zhao, Jun; McMurry, Peter H

    2012-11-13

    Climate models show that particles formed by nucleation can affect cloud cover and, therefore, the earth's radiation budget. Measurements worldwide show that nucleation rates in the atmospheric boundary layer are positively correlated with concentrations of sulfuric acid vapor. However, current nucleation theories do not correctly predict either the observed nucleation rates or their functional dependence on sulfuric acid concentrations. This paper develops an alternative approach for modeling nucleation rates, based on a sequence of acid-base reactions. The model uses empirical estimates of sulfuric acid evaporation rates obtained from new measurements of neutral molecular clusters. The model predicts that nucleation rates equal the sulfuric acid vapor collision rate times a prefactor that is less than unity and that depends on the concentrations of basic gaseous compounds and preexisting particles. Predicted nucleation rates and their dependence on sulfuric acid vapor concentrations are in reasonable agreement with measurements from Mexico City and Atlanta.

  11. The Upside to Hg-DOM Associations for Water Quality: Removal of Hg from Solution Using Coagulaion with Metal-Based Salts

    Science.gov (United States)

    Henneberry, Y.; Kraus, T. E.; Fleck, J.; Krabbenhoft, D. P.; Horwath, W. R.

    2011-12-01

    This study assessed the potential use of metal-based coagulants to remove dissolved mercury (Hg) from natural waters and provides information regarding the importance of Hg associations with the dissolved organic matter (DOM) fraction and metal hydroxides. Previous research indicated coagulants were not effective at removing Hg from solution; however those studies used high concentrations of Hg, which did not reflect naturally occurring concentrations of Hg. Filtered water collected from an agricultural drain in the Sacramento-San Joaquin Delta (Delta) was treated with three industrial-grade coagulants (ferric chloride, ferric sulfate, and polyaluminum chloride) to determine their efficacy in removing both inroganic (IHg) and methylmercury (MeHg) from the water column. The Delta suffers from elevated surface water Hg concentrations and as a result is listed as an imparied water body. Coagulants removed up to 85% of DOM from solution. In the absence of DOM, all three coagulants released IHg into solution, however in the presence of DOM the coagulants removed up to 97% of IHg and 80% of MeHg. Results suggest that the removal of Hg is mediated by DOM-coagulant interactions. There was a preferential association of IHg with the more aromatic, higher molecular weight fraction of DOM but no such relationship was found for MeHg. This study offers new fundamental insights regarding large-scale removal of Hg at environmentally relevant concentrations. Research using isotopically labeled Hg is providing insight into whether coagulation can remove recently added Hg (e.g. atmospheric deposition) from solution and whether once formed, the floc can remove additional Hg from the water column.

  12. A unified canonical correlation analysis-based framework for removing gradient artifact in concurrent EEG/fMRI recording and motion artifact in walking recording from EEG signal.

    Science.gov (United States)

    Li, Junhua; Chen, Yu; Taya, Fumihiko; Lim, Julian; Wong, Kianfoong; Sun, Yu; Bezerianos, Anastasios

    2017-09-01

    Artifacts cause distortion and fuzziness in electroencephalographic (EEG) signal and hamper EEG analysis, so it is necessary to remove them prior to the analysis. Particularly, artifact removal becomes a critical issue in experimental protocols with significant inherent recording noise, such as mobile EEG recordings and concurrent EEG-fMRI acquisitions. In this paper, we proposed a unified framework based on canonical correlation analysis for artifact removal. Raw signals were reorganized to construct a pair of matrices, based on which sources were sought through maximizing autocorrelation. Those sources related to artifacts were then removed by setting them as zeros, and the remaining sources were used to reconstruct artifact-free EEG. Both simulated and real recorded data were utilized to assess the proposed framework. Qualitative and quantitative results showed that the proposed framework was effective to remove artifacts from EEG signal. Specifically, the proposed method outperformed independent component analysis method for mitigating motion-related artifacts and had advantages for removing gradient artifact compared to the classical method (average artifacts subtraction) and the state-of-the-art method (optimal basis set) in terms of the combination of performance and computational complexity.

  13. Picosecond-pulse generation over 10 GHz repetition rate based on cascaded semiconductor optical amplifiers

    Science.gov (United States)

    Tai, Wenlong; Yang, Tianxin; Ge, Chunfeng; Jia, Dongfang

    2017-02-01

    A cavity-free setup to generate short pulses at high repetition rate is introduced, which is based on four-wave mixing (FWM) in cascaded semiconductor optical amplifiers (SOAs). High repetition rate picosecond-pulse is important in optical communication and all-optic information processing systems. Cavity-free setup based on SOA means without ring cavity, which is stable and easy to be large-scale integrated. In this paper, we obtain picosecond-pulse around 10GHz repetition rate and the side-mode suppression ratio is 23 dB. Moreover, the repetition rate and center wavelength of optical pulse is tunable.

  14. On-site phytoremediation applicability assessment in Alur Ilmu, Universiti Kebangsaan Malaysia based on spatial and pollution removal analyses.

    Science.gov (United States)

    Mahmud, Mohd Hafiyyan; Lee, Khai Ern; Goh, Thian Lai

    2017-10-01

    The present paper aims to assess the phytoremediation performance based on pollution removal efficiency of the highly polluted region of Alur Ilmu urban river for its applicability of on-site treatment. Thirteen stations along Alur Ilmu were selected to produce thematic maps through spatial distribution analysis based on six water quality parameters of Malaysia's Water Quality Index (WQI) for dry and raining seasons. The maps generated were used to identify the highly polluted region for phytoremediation applicability assessment. Four free-floating plants were tested in treating water samples from the highly polluted region under three different conditions, namely controlled, aerated and normal treatments. The selected free-floating plants were water hyacinth (Eichhornia crassipes), water lettuce (Pistia stratiotes), rose water lettuce (Pistia sp.) and pennywort (Centella asiatica). The results showed that Alur Ilmu was more polluted during dry season compared to raining season based on the water quality analysis. During dry season, four parameters were marked as polluted along Alur Ilmu, namely dissolve oxygen (DO), 4.72 mg/L (class III); ammoniacal nitrogen (NH3-N), 0.85 mg/L (class IV); total suspended solid (TSS), 402 mg/L (class V) and biological oxygen demand (BOD), 3.89 mg/L (class III), whereas, two parameters were classed as polluted during raining season, namely total suspended solid (TSS), 571 mg/L (class V) and biological oxygen demand (BOD), 4.01 mg/L (class III). The thematic maps generated from spatial distribution analysis using Kriging gridding method showed that the highly polluted region was recorded at station AL 5. Hence, water samples were taken from this station for pollution removal analysis. All the free-floating plants were able to reduce TSS and COD in less than 14 days. However, water hyacinth showed the least detrimental effect from the phytoremediation process compared to other free-floating plants, thus made it a suitable free

  15. Projections of population-based twinning rates through the year 2100.

    Science.gov (United States)

    Oleszczuk, J J; Keith, D M; Keith, L G; Rayburn, W F

    1999-11-01

    To present the first compilation of population-based twinning rates published after the year 1990 and to project population-based twinning rates through the year 2100. We searched the Internet-based MEDLINE database for articles published after 1990 in which population-based twinning rates were described. We used population-based data from national statistical authorities from Australia, Austria, Canada, Finland, Hong Kong, Israel, Japan, Norway, Singapore and Sweden, published by Y. Imaizumi in a recent article. U.S. figures were based