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  1. Soft Measurement Modeling Based on Chaos Theory for Biochemical Oxygen Demand (BOD

    Directory of Open Access Journals (Sweden)

    Junfei Qiao

    2016-12-01

    Full Text Available The precision of soft measurement for biochemical oxygen demand (BOD is always restricted due to various factors in the wastewater treatment plant (WWTP. To solve this problem, a new soft measurement modeling method based on chaos theory is proposed and is applied to BOD measurement in this paper. Phase space reconstruction (PSR based on Takens embedding theorem is used to extract more information from the limited datasets of the chaotic system. The WWTP is first testified as a chaotic system by the correlation dimension (D, the largest Lyapunov exponents (λ1, the Kolmogorov entropy (K of the BOD and other water quality parameters time series. Multivariate chaotic time series modeling method with principal component analysis (PCA and artificial neural network (ANN is then adopted to estimate the value of the effluent BOD. Simulation results show that the proposed approach has higher accuracy and better prediction ability than the corresponding modeling approaches not based on chaos theory.

  2. PROPOSED MODIFICATIONS OF K2-TEMPERATURE RELATION AND LEAST SQUARES ESTIMATES OF BOD (BIOCHEMICAL OXYGEN DEMAND) PARAMETERS

    Science.gov (United States)

    A technique is presented for finding the least squares estimates for the ultimate biochemical oxygen demand (BOD) and rate coefficient for the BOD reaction without resorting to complicated computer algorithms or subjective graphical methods. This may be used in stream water quali...

  3. Modeling and Forecast Biological Oxygen Demand (BOD using Combination Support Vector Machine with Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Abazar Solgi

    2017-06-01

    given from Fourier transform that was introduced in the nineteenth-century. Overall, concept of wavelet transform for current theory was presented by Morlet and a team under the supervision of Alex Grossman at the Research Center for Theoretical Physics Marcel in France. After the parameters decomposition using wavelet analysis and using principal component analysis (PCA, the main components were determined. These components are then used as input to the support vector machine model to obtain a hybrid model of Wavelet-SVM (WSVM. For this study, a series of monthly of BOD in Karun River in Molasani station and auxiliary variables dissolved oxygen (DO, temperature and monthly river flow in a 13 years period (2002-2014 were used. Results and Discussion: To run the SVM model, seven different combinations were evaluated. Combination 6 which was contained of 4 parameters including BOD, dissolved oxygen (DO, temperature and monthly river flow with a time lag have best performance. The best structure had RMSE equal to 0.0338 and the coefficient of determination equal to 0.84. For achieving the results of the WSVM, the wavelet transform and input parameters were decomposed to sub-signal, then this sub-signals were studied with Principal component analysis (PCA method and important components were entered as inputs to SVM model to obtain the hybrid model WSVM. After numerous run this program in certain modes and compare them with each other, the results was obtained. One of the key points about the choice of the mother wavelet is the time series. So, the patterns of the mother wavelet functions that can better adapt to diagram curved of time series can do the mappings operation and therefore will have better results. In this study, according to different wavelet tests and according to the above note, four types of mother wavelet functions Haar, Db2, Db7 and Sym3 were selected. Conclusions: Compare the results of the monthly modeling indicate that the use of wavelet transforms can

  4. Biological Oxygen Demand in Soils and Litters

    Science.gov (United States)

    Smagin, A. V.; Smagina, M. V.; Sadovnikova, N. B.

    2018-03-01

    Biological oxygen demand (BOD) in mineral and organic horizons of soddy-podzolic soils in the forest-park belt of Moscow as an indicator of their microbial respiration and potential biodestruction function has been studied. The BOD of soil samples has been estimated with a portable electrochemical analyzer after incubation in closed flasks under optimum hydrothermal conditions. A universal gradation scale of this parameter from very low (140 g O2/(m3 h)) has been proposed for mineral and organic horizons of soil. A physically substantiated model has been developed for the vertical distribution of BOD in the soil, which combines the diffusion transport of oxygen from the atmosphere and its biogenic uptake in the soil by the first-order reaction. An analytical solution of the model in the stationary state has been obtained; from it, the soil oxygen diffusivity and the kinetic constants of O2 uptake have been estimated, and the profile-integrated total BOD value has been calculated (0.4-1.8 g O2/(m2 h)), which is theoretically identical to the potential oxygen flux from the soil surface due to soil respiration. All model parameters reflect the recreation load on the soil cover by the decrease in their values against the control.

  5. Facultative Stabilization Pond: Measuring Biological Oxygen Demand using Mathematical Approaches

    Science.gov (United States)

    Wira S, Ihsan; Sunarsih, Sunarsih

    2018-02-01

    Pollution is a man-made phenomenon. Some pollutants which discharged directly to the environment could create serious pollution problems. Untreated wastewater will cause contamination and even pollution on the water body. Biological Oxygen Demand (BOD) is the amount of oxygen required for the oxidation by bacteria. The higher the BOD concentration, the greater the organic matter would be. The purpose of this study was to predict the value of BOD contained in wastewater. Mathematical modeling methods were chosen in this study to depict and predict the BOD values contained in facultative wastewater stabilization ponds. Measurements of sampling data were carried out to validate the model. The results of this study indicated that a mathematical approach can be applied to predict the BOD contained in the facultative wastewater stabilization ponds. The model was validated using Absolute Means Error with 10% tolerance limit, and AME for model was 7.38% (< 10%), so the model is valid. Furthermore, a mathematical approach can also be applied to illustrate and predict the contents of wastewater.

  6. Oxygen demand of aircraft and airfield pavement deicers and alternative freezing point depressants

    Science.gov (United States)

    Corsi, Steven R.; Mericas, Dean; Bowman, George

    2012-01-01

    Aircraft and pavement deicing formulations and other potential freezing point depressants were tested for biochemical oxygen demand (BOD) and chemical oxygen demand (COD). Propylene glycol-based aircraft deicers exhibited greater BOD5 than ethylene glycol-based aircraft deicers, and ethylene glycol-based products had lower degradation rates than propylene glycol-based products. Sodium formate pavement deicers had lower COD than acetate-based pavement deicers. The BOD and COD results for acetate-based pavement deicers (PDMs) were consistently lower than those for aircraft deicers, but degradation rates were greater in the acetate-based PDM than in aircraft deicers. In a 40-day testing of aircraft and pavement deicers, BOD results at 20°C (standard) were consistently greater than the results from 5°C (low) tests. The degree of difference between standard and low temperature BOD results varied among tested products. Freshwater BOD test results were not substantially different from marine water tests at 20°C, but glycols degraded slower in marine water than in fresh water for low temperature tests. Acetate-based products had greater percentage degradation than glycols at both temperatures. An additive component of the sodium formate pavement deicer exhibited toxicity to the microorganisms, so BOD testing did not work properly for this formulation. BOD testing of alternative freezing point depressants worked well for some, there was little response for some, and for others there was a lag in response while microorganisms acclimated to the freezing point depressant as a food source. Where the traditional BOD5 test performed adequately, values ranged from 251 to 1,580 g/kg. Where the modified test performed adequately, values of BOD28 ranged from 242 to 1,540 g/kg.

  7. Determination of Biochemical Oxygen Demand of Area Waters: A Bioassay Procedure for Environmental Monitoring

    Science.gov (United States)

    Riehl, Matthew

    2012-01-01

    A graphical method for determining the 5-day biochemical oxygen demand (BOD5) for a body of water is described. In this bioassay, students collect a sample of water from a designated site, transport it to the laboratory, and evaluate the amount of oxygen consumed by naturally occurring bacteria during a 5-day incubation period. An accuracy check,…

  8. THE DEVELOPMENT OF BIOCHEMICAL OXYGEN DEMAND SENSOR USING LOCAL YEAST: Candida fukuyamaensis, UICC Y-247

    Directory of Open Access Journals (Sweden)

    Endang Saepudin

    2011-04-01

    Full Text Available In order to shorten the measurement time of biochemical oxygen demand (BOD, a BOD sensor based on yeastmetabolism was developed. Local yeast, Indonesian Origin, Candida fukuyamaensis UICC Y-247, was used as atransducer. The yeast was immobilized as a thin film in agarose matrix with the auxiliary of Nafion® acting as themembrane for ion exchange process. The film was then attached to gold-modified glassy carbons and used as transduceron the working electrodes. The measurements were conducted by observing the depletion of glucose concentrationusing multipulse amperometric method and then converted to BOD values. Optimum condition was observed in awaiting measurement time of 30 min at an applied potential of 450 mV (vs. Ag/AgCl. Linearity was shown in glucoseconcentration range of 0.1–0.5 mM, which was equivalent to BOD concentration range of 10–50 mg/L. A detectionlimit of 1.13 mg/L BOD could be achieved. Good repeatability was shown by a relative standard deviation (RSD of2.7% (n = 15. However, decreasing current response of ~50% was found after 3 days. Comparing to the conventionalBOD measurement, this BOD sensor can be used as an alternative method for BOD measurements.

  9. Simulation of temperature distribution, BOD, and DO by thermal effluents of power plants

    International Nuclear Information System (INIS)

    Haeuser, J.

    1977-01-01

    A transient one, two, or three dimensional numerical model for simulation of heat load by power plants is presented. Water quality is determined by three parameters: temperature, biological oxygen demand (BOD), and disolved oxygen (DO). (orig.) [de

  10. An optical biosensing film for biochemical oxygen demand determination in seawater with an automatic flow sampling system

    Science.gov (United States)

    Xin, Lingling; Wang, Xudong; Guo, Guangmei; Wang, Xiaoru; Chen, Xi

    2007-09-01

    An on-line roboticized apparatus, including an optical biosensing film with an automatic flow sampling system, has been developed for biochemical oxygen demand (BOD) determination of seawater. The sensing film employed in the apparatus consisted of an organically modified silicate (ORMOSIL) film embedded with tri(4,7-diphenyl-1,10-phenanthroline) ruthenium(II) perchlorate. Three species of microorganism cultivated from seawater were immobilized in an ORMOSIL-polyvinyl alcohol matrix. Possible factors affecting BOD determination were studied, including sampling frequency, temperature, pH and sodium chloride concentration. Based on measurements of the linear fluctuant coefficients and the reproducibility of its response to seawater, the BOD apparatus showed the advantages of high veracity and short response time. Generally, the linear fluctuant coefficient (R2) in the BOD range 0.2-40 mg l-1 was 0.9945 when using a glucose/glutamate (GGA) BOD standard solution. A reproducible response for the BOD sensing film of within ±2.8% could be obtained in the 2 mg l-1 GGA solution. The BOD apparatus was applied to the BOD determination of seawater, and the values estimated by this biosensing apparatus correlated well with those determined by the conventional 5 day BOD (BOD5) test.

  11. Effects of Operating Parameters on Measurements of Biochemical Oxygen Demand Using a Mediatorless Microbial Fuel Cell Biosensor

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    Min-Chi Hsieh

    2015-12-01

    Full Text Available The conventional Biochemical Oxygen Demand (BOD method takes five days to analyze samples. A microbial fuel cell (MFC may be an alternate tool for rapid BOD determination in water. However, a MFC biosensor for continuous BOD measurements of water samples is still unavailable. In this study, a MFC biosensor inoculated with known mixed cultures was used to determine the BOD concentration. Effects of important parameters on establishing a calibration curve between the BOD concentration and output signal from the MFC were evaluated. The results indicate monosaccharides were good fuel, and methionine, phenylalanine, and ethanol were poor fuels for electricity generation by the MFC. Ions in the influent did not significantly affect the MFC performance. CN− in the influent could alleviate the effect of antagonistic electron acceptors on the MFC performance. The regression equation for BOD concentration and current density of the biosensor was y = 0.0145x + 0.3317. It was adopted to measure accurately and continuously the BOD concentration in actual water samples at an acceptable error margin. These results clearly show the developed MFC biosensor has great potential as an alternative BOD sensing device for online measurements of wastewater BOD.

  12. Experimental demonstration of bandwidth on demand (BoD) provisioning based on time scheduling in software-defined multi-domain optical networks

    Science.gov (United States)

    Zhao, Yongli; Li, Yajie; Wang, Xinbo; Chen, Bowen; Zhang, Jie

    2016-09-01

    A hierarchical software-defined networking (SDN) control architecture is designed for multi-domain optical networks with the Open Daylight (ODL) controller. The OpenFlow-based Control Virtual Network Interface (CVNI) protocol is deployed between the network orchestrator and the domain controllers. Then, a dynamic bandwidth on demand (BoD) provisioning solution is proposed based on time scheduling in software-defined multi-domain optical networks (SD-MDON). Shared Risk Link Groups (SRLG)-disjoint routing schemes are adopted to separate each tenant for reliability. The SD-MDON testbed is built based on the proposed hierarchical control architecture. Then the proposed time scheduling-based BoD (Ts-BoD) solution is experimentally demonstrated on the testbed. The performance of the Ts-BoD solution is evaluated with respect to blocking probability, resource utilization, and lightpath setup latency.

  13. Factors affecting the performance of a single-chamber microbial fuel cell-type biological oxygen demand sensor.

    Science.gov (United States)

    Yang, Gai-Xiu; Sun, Yong-Ming; Kong, Xiao-Ying; Zhen, Feng; Li, Ying; Li, Lian-Hua; Lei, Ting-Zhou; Yuan, Zhen-Hong; Chen, Guan-Yi

    2013-01-01

    Microbial fuel cells (MFCs) are devices that exploit microorganisms as biocatalysts to degrade organic matter or sludge present in wastewater (WW), and thereby generate electricity. We developed a simple, low-cost single-chamber microbial fuel cell (SCMFC)-type biochemical oxygen demand (BOD) sensor using carbon felt (anode) and activated sludge, and demonstrated its feasibility in the construction of a real-time BOD measurement system. Further, the effects of anodic pH and organic concentration on SCMFC performance were examined, and the correlation between BOD concentration and its response time was analyzed. Our results demonstrated that the SCMFC exhibited a stable voltage after 132 min following the addition of synthetic WW (BOD concentration: 200 mg/L). Notably, the response signal increased with an increase in BOD concentration (range: 5-200 mg/L) and was found to be directly proportional to the substrate concentration. However, at higher BOD concentrations (>120 mg/L) the response signal remained unaltered. Furthermore, we optimized the SCMFC using synthetic WW, and tested it with real WW. Upon feeding real WW, the BOD values exhibited a standard deviation from 2.08 to 8.3% when compared to the standard BOD5 method, thus demonstrating the practical applicability of the developed system to real treatment effluents.

  14. Enhanced response of microbial fuel cell using sulfonated poly ether ether ketone membrane as a biochemical oxygen demand sensor

    Energy Technology Data Exchange (ETDEWEB)

    Ayyaru, Sivasankaran; Dharmalingam, Sangeetha, E-mail: sangeetha@annauniv.edu

    2014-03-01

    Graphical abstract: - Highlights: • Sulfonated poly ether ether ketone (SPEEK) membrane in SCMFC used to determine the BOD. • The biosensor produces a good linear relationship with the BOD concentration up to 650 ppm. • This sensing range was 62.5% higher than that of Nafion{sup ®}. • SPEEK exhibited one order lesser oxygen permeability than Nafion{sup ®}. • Nafion{sup ®} shows high anodic internal resistance (67 Ω) than the SPEEK (39 Ω). - Abstract: The present study is focused on the development of single chamber microbial fuel cell (SCMFC) using sulfonated poly ether ether ketone (SPEEK) membrane to determine the biochemical oxygen demand (BOD) matter present in artificial wastewater (AW). The biosensor produces a good linear relationship with the BOD concentration up to 650 ppm when using artificial wastewater. This sensing range was 62.5% higher than that of Nafion{sup ®}. The most serious problem in using MFC as a BOD sensor is the oxygen diffusion into the anode compartment, which consumes electrons in the anode compartment, thereby reducing the coulomb yield and reducing the electrical signal from the MFC. SPEEK exhibited one order lesser oxygen permeability than Nafion{sup ®}, resulting in low internal resistance and substrate loss, thus improving the sensing range of BOD. The system was further improved by making a double membrane electrode assembly (MEA) with an increased electrode surface area which provide high surface area for electrically active bacteria.

  15. Electrocoagulation process to Chemical and Biological Oxygen Demand treatment from carwash grey water in Ahvaz megacity, Iran.

    Science.gov (United States)

    Mohammadi, Mohammad Javad; Takdastan, Afshin; Jorfi, Sahand; Neisi, Abdolkazem; Farhadi, Majid; Yari, Ahmad Reza; Dobaradaran, Sina; Khaniabadi, Yusef Omidi

    2017-04-01

    In this work, we present the result of an electric coagulation process with iron and aluminum electrodes for removal of chemical and biological oxygen demand (COD and BOD) from grey water in different car washes of Ahvaz, Iran. Nowadays, one of the important dangerous that can contaminate water resources for drinking, agriculture and industrial is Car wash effluent [1,2]. In this study, initial COD and BOD concentration, pH of the solution, voltage power and reaction time was investigated. The concentration level of remaining COD and BOD in samples was measured, using DR/5000 UV-vis HACH spectrophotometer [3,4]. The effects of contact time, initial pH, electrical potential and voltage data on removal of COD and BOD were presented. Statistical analysis of the data was carried out using Special Package for Social Sciences (SPSS 16).

  16. Electrocoagulation process to Chemical and Biological Oxygen Demand treatment from carwash grey water in Ahvaz megacity, Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Javad Mohammadi

    2017-04-01

    Full Text Available In this work, we present the result of an electric coagulation process with iron and aluminum electrodes for removal of chemical and biological oxygen demand (COD and BOD from grey water in different car washes of Ahvaz, Iran. Nowadays, one of the important dangerous that can contaminate water resources for drinking, agriculture and industrial is Car wash effluent [1,2]. In this study, initial COD and BOD concentration, pH of the solution, voltage power and reaction time was investigated. The concentration level of remaining COD and BOD in samples was measured, using DR/5000 UV–vis HACH spectrophotometer [3,4]. The effects of contact time, initial pH, electrical potential and voltage data on removal of COD and BOD were presented. Statistical analysis of the data was carried out using Special Package for Social Sciences (SPSS 16.

  17. A BOD monitoring disposable reactor with alginate-entrapped bacteria.

    Science.gov (United States)

    Villalobos, Patricio; Acevedo, Cristian A; Albornoz, Fernando; Sánchez, Elizabeth; Valdés, Erika; Galindo, Raúl; Young, Manuel E

    2010-10-01

    Biochemical oxygen demand (BOD) is a measure of the amount of dissolved oxygen that is required for the biochemical oxidation of the organic compounds in 5 days. New biosensor-based methods have been conducted for a faster determination of BOD. In this study, a mathematical model to evaluate the feasibility of using a BOD sensor, based on disposable alginate-entrapped bacteria, for monitoring BOD in situ was applied. The model considers the influences of alginate bead size and bacterial concentration. The disposable biosensor can be adapted according to specific requirements depending on the organic load contained in the wastewater. Using Klein and Washausen parameter in a Lineweaver-Burk plot, the glucose diffusivity was calculated in 6.4 × 10(-10) (m2/s) for beads of 1 mm in diameter and slight diffusion restrictions were observed (n = 0.85). Experimental results showed a correlation (p < 0.05) between the respirometric peak and the standard BOD test. The biosensor response was representative of BOD.

  18. Measurement of biological oxygen demand sandy beaches

    African Journals Online (AJOL)

    Measurements of biological oxygen demand in a sandy beach using conventional .... counting the cells present in a sample of aged seawater and comparing this with .... This activity peaked at 71 % above the undisturbed level after 16 hours.

  19. BOD-DO modeling and water quality analysis of a waste water outfall off Kochi, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Babu, M.T.; Das, V.K.; Vethamony, P.

    Water quality scenarios around an offshore outfall off Kochi were simulated using MIKE21 water quality model, assuming a high Biochemical Oxygen Demand (BOD=50 mgl sup(-1)) effluent discharge. The discharge is introduced into the model through...

  20. Replacement of chemical oxygen demand (COD) with total organic carbon (TOC) for monitoring wastewater treatment performance to minimize disposal of toxic analytical waste.

    Science.gov (United States)

    Dubber, Donata; Gray, Nicholas F

    2010-10-01

    Chemical oxygen demand (COD) is widely used for wastewater monitoring, design, modeling and plant operational analysis. However this method results in the production of hazardous wastes including mercury and hexavalent chromium. The study examined the replacement of COD with total organic carbon (TOC) for general performance monitoring by comparing their relationship with influent and effluent samples from 11 wastewater treatment plants. Biochemical oxygen demand (BOD5) was also included in the comparison as a control. The results show significant linear relationships between TOC, COD and BOD5 in settled (influent) domestic and municipal wastewaters, but only between COD and TOC in treated effluents. The study concludes that TOC can be reliably used for the generic replacement of both COD (COD=49.2+3.00*TOC) and BOD5 (BOD5=23.7+1.68*TOC) in influent wastewaters but only for COD (COD=7.25+2.99*TOC) in final effluents.

  1. Biological oxygen demand in soils and hydrogel compositions for plant protection of the rhizosphere

    Science.gov (United States)

    Valentinovich Smagin, Andrey

    2018-02-01

    Potential biological activity of mineral and organogenic samples from light-textured sod-podzolic soils as well as of hydrogel compositions for protecting the root layer from pathogenic microflora and unfavorable edaphic factors were studied in laboratory conditions by oxygen consumption under the optimal hydrothermic conditions with portable gas analyzers. We have conducted ecological standardization of biological activity and organic matter destruction estimated by biological oxygen demand (BOD) in the widespread sandy soils. The primary outcome was the scale of gradations of biological oxygen uptake in soils with a range of quantities of potential biological activity from “very low” (140 g·m-3·hour-1), obtained on the basis of statistical processing of data array 1308 measurements. Acrylic polymer hydrogels had BOD = 0.2-2 g·m-3·hour-1, which corresponded to the periods of their half-lives from 0.2±0.1 to 6.8± 4.5 years, or relatively low resistance to biodestruction. In contrast to the pure gels, hydrogel compositions for rhizosphere based on ionic and colloidal silver showed low biological activity (BOD=0.01-0.2 g·m-3· hour-1) and, accordingly, significant resistance to biodegradation with half-lives from 5 to 70 years and above.

  2. Determination of Biological Oxygen Demand Rate Constant and ...

    African Journals Online (AJOL)

    Determination of Biological Oxygen Demand Rate Constant and Ultimate Biological Oxygen Demand for Liquid Waste Generated from Student Cafeteria at Jimma University: A Tool for Development of Scientific Criteria to Protect Aquatic Health in the Region.

  3. Use of COD, TOC, and Fluorescence Spectroscopy to Estimate BOD in Wastewater.

    Science.gov (United States)

    Christian, Evelyn; Batista, Jacimaria R; Gerrity, Daniel

    2017-02-01

      Common to all National Pollutant Discharge Elimination System (NPDES) permits in the United States is a limit on biochemical oxygen demand (BOD). Chemical oxygen demand (COD), total organic carbon (TOC), and fluorescence spectroscopy are also capable of quantifying organic content, although the mechanisms of quantification and the organic fractions targeted differ for each test. This study explores correlations between BOD5 and these alternate test procedures using facility influent, primary effluent, and facility effluent samples from a full-scale water resource recovery facility. Relative reductions of the water quality parameters proved to be strong indicators of their suitability as surrogates for BOD5. Suitable correlations were generally limited to the combined datasets for the three sampling locations or the facility effluent alone. COD exhibited relatively strong linear correlations with BOD5 when considering the three sample points (r = 0.985) and the facility effluent alone (r = 0.914), while TOC exhibited a suitable linear correlation with BOD5 in the facility effluent (r = 0.902). Exponential regressions proved to be useful for estimating BOD5 based on TOC or fluorescence (r > 0.95).

  4. Relationships between water quality parameters in rivers and lakes: BOD5, COD, NBOPs, and TOC.

    Science.gov (United States)

    Lee, Jaewoong; Lee, Seunghyun; Yu, Soonju; Rhew, Doughee

    2016-04-01

    Biological oxygen demand (BOD5) or chemical oxygen demand (COD) analysis is widely used to evaluate organic pollutants in water systems as well as the efficiency of wastewater treatment plants. However, both analysis methods have restrictions such as being insensitive, imprecise, time-consuming, and the production of chemical waste. Therefore, total organic carbon (TOC) analysis for organic pollutants has been considered for an alternative analysis instead of BOD5 or COD. Several studies have investigated the replacement of BOD5 or COD with TOC in wastewater samples; however, few studies have investigated the relationships between water quality parameters in rivers and lakes. Therefore, this study evaluated the relationships between BOD5, COD, or NBOPs and TOC by the analysis of national water quality monitoring data of rivers and lakes for 5 years. High correlation coefficients (r) of 0.87 and 0.66 between BOD5 and TOC (p TOC (p TOC was 0.93 for rivers and 0.72 for lakes. The coefficients of determination (R 2) were 0.75 and 0.44 between BOD5 and TOC for rivers and lakes as well as were 0.87 and 0.57 between COD and TOC for rivers and lakes, respectively. The coefficient of determination (R 2) between NBOPs and TOC was 0.73 for rivers and 0.52 for lakes.

  5. Microbial BOD sensors based on Zr (IV)-loaded collagen fiber.

    Science.gov (United States)

    Zhao, Lei; He, Li; Chen, Shujuan; Zou, Likou; Zhou, Kang; Ao, Xiaolin; Liu, Shuliang; Hu, Xinjie; Han, Guoquan

    2017-03-01

    Biochemical oxygen demand (BOD) sensors based on Zr (IV)-loaded collagen fiber (ZrCF), a novel material with great porous structure, were developed. This novel material shows adsorbability by microorganisms. Saccharomyces cerevisiae and Escherichia coli were used for the construction of BOD sensors. Factors affecting BOD sensor performance were examined. The ZrCF-based BOD sensor showed different sensitivities and linear response ranges with different biofilm densities. The amount of microorganisms strongly affected the performance of the BOD sensor. Poor permeability of previously reported immobilization carriers were greatly circumvented by ZrCF. The service life of the ZrCF-based BOD sensor was more than 42 days. The immobilized microorganisms can be stored for more than 6 months under 4°C in PB solution. There was good correlation between the results of the sensor method and the standard 5-day BOD method in the determination of pure organic substrates and real water samples. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Rapid adaptation of activated sludge bacteria into a glycogen accumulating biofilm enabling anaerobic BOD uptake.

    Science.gov (United States)

    Hossain, Md Iqbal; Paparini, Andrea; Cord-Ruwisch, Ralf

    2017-03-01

    Glycogen accumulating organisms (GAO) are known to allow anaerobic uptake of biological oxygen demand (BOD) in activated sludge wastewater treatment systems. In this study, we report a rapid transition of suspended activated sludge biomass to a GAO dominated biofilm by selective enrichment using sequences of anaerobic loading followed by aerobic exposure of the biofilm to air. The study showed that within eight weeks, a fully operational, GAO dominated biofilm had developed, enabling complete anaerobic BOD uptake at a rate of 256mg/L/h. The oxygen uptake by the biofilm directly from the atmosphere had been calculated to provide significant energy savings. This study suggests that wastewater treatment plant operators can convert activated sludge systems readily into a "passive aeration" biofilm that avoids costly oxygen transfer to bulk wastewater solution. The described energy efficient BOD removal system provides an opportunity to be coupled with novel nitrogen removal processes such as anammox. Copyright © 2016. Published by Elsevier Ltd.

  7. Performance of a modified multi-stage bubble column reactor for lead(II) and biological oxygen demand removal from wastewater using activated rice husk

    International Nuclear Information System (INIS)

    Sahu, J.N.; Agarwal, S.; Meikap, B.C.; Biswas, M.N.

    2009-01-01

    The excessive release of wastewater into the environment is a major concern worldwide. Adsorption is the one of the most effective technique for treatment of wastewater. In this work activated carbon prepared from rice husk has been used as an adsorbent. In the present investigation a three phase modified multi-stage bubble column reactor (MMBCR) has been designed to remove lead and biochemical oxygen demand (BOD) from wastewater by means of its adsorption onto the surface of activated rice husk. The multi-staging has been achieved by hydrodynamically induced continuous bubble generation, breakup and regeneration. Under optimum conditions, maximum lead and BOD reduction achieved using activated rice husk was 77.15% and 19.05%, respectively. Results showed MMBCR offered appreciated potential benefits for lead removal from wastewater and BOD removal, even this extent of removal is encouraging and the MMBCR can be used a pretreatment unit before subjecting the wastewater to biological treatment

  8. Performance of a modified multi-stage bubble column reactor for lead(II) and biological oxygen demand removal from wastewater using activated rice husk.

    Science.gov (United States)

    Sahu, J N; Agarwal, S; Meikap, B C; Biswas, M N

    2009-01-15

    The excessive release of wastewater into the environment is a major concern worldwide. Adsorption is the one of the most effective technique for treatment of wastewater. In this work activated carbon prepared from rice husk has been used as an adsorbent. In the present investigation a three phase modified multi-stage bubble column reactor (MMBCR) has been designed to remove lead and biochemical oxygen demand (BOD) from wastewater by means of its adsorption onto the surface of activated rice husk. The multi-staging has been achieved by hydrodynamically induced continuous bubble generation, breakup and regeneration. Under optimum conditions, maximum lead and BOD reduction achieved using activated rice husk was 77.15% and 19.05%, respectively. Results showed MMBCR offered appreciated potential benefits for lead removal from wastewater and BOD removal, even this extent of removal is encouraging and the MMBCR can be used a pretreatment unit before subjecting the wastewater to biological treatment.

  9. Chemical oxygen demand (cod) attenuation of methyl red in water ...

    African Journals Online (AJOL)

    Chemical oxygen demand (cod) attenuation of methyl red in water using biocarbons obtained from Nipa palm leaves. ... eco-friendly and locally accessible biocarbon for mitigation of organic contaminants in water. Keywords: Chemical oxygen demand, biocarbon, methyl red, biodegradation, bioremediation, Nipa palm ...

  10. Submersible microbial fuel cell sensor for monitoring microbial activity and BOD in groundwater: Focusing on impact of anodic biofilm on sensor applicability

    DEFF Research Database (Denmark)

    Zhang, Yifeng; Angelidaki, Irini

    2011-01-01

    was required for application of the sensor for microbial activity measurement, while biofilm‐colonized anode was needed for utilizing the sensor for BOD content measurement. The current density of SUMFC sensor equipped with a biofilm‐colonized anode showed linear relationship with BOD content, to up to 250 mg......A sensor, based on a submersible microbial fuel cell (SUMFC), was developed for in situ monitoring of microbial activity and biochemical oxygen demand (BOD) in groundwater. Presence or absence of a biofilm on the anode was a decisive factor for the applicability of the sensor. Fresh anode...

  11. Right ventricular oxygen supply/demand balance in exercising dogs.

    Science.gov (United States)

    Hart, B J; Bian, X; Gwirtz, P A; Setty, S; Downey, H F

    2001-08-01

    This is the first investigation of right ventricular (RV) myocardial oxygen supply/demand balance in a conscious animal. A novel technique developed in our laboratory was used to collect right coronary (RC) venous blood samples from seven instrumented, conscious dogs at rest and during graded treadmill exercise. Contributions of the RV oxygen extraction reserve and the RC flow reserve to exercise-induced increases in RV oxygen demand were measured. Strenuous exercise caused a 269% increase in RV oxygen consumption. Expanded arteriovenous oxygen content difference (A-V(Delta)O2) provided 58% of this increase in oxygen demand, and increased RC blood flow (RCBF) provided 42%. At less strenuous exercise, expanded A-V(Delta)O2 provided 60-80% of the required oxygen, and increases in RCBF were small and driven by increased aortic pressure. RC resistance fell only at strenuous exercise after the extraction reserve had been mobilized. Thus RC resistance was unaffected by large decreases in RC venous PO2 until an apparent threshold at 20 mmHg was reached. Comparisons of RV findings with published left ventricular data from exercising dogs demonstrated that increased O2 demand of the left ventricle is met primarily by increasing coronary flow, whereas increased O2 extraction makes a greater contribution to RV O2 supply.

  12. A theoretical model for oxygen transport in skeletal muscle under conditions of high oxygen demand.

    Science.gov (United States)

    McGuire, B J; Secomb, T W

    2001-11-01

    Oxygen transport from capillaries to exercising skeletal muscle is studied by use of a Krogh-type cylinder model. The goal is to predict oxygen consumption under conditions of high demand, on the basis of a consideration of transport processes occurring at the microvascular level. Effects of the decline in oxygen content of blood flowing along capillaries, intravascular resistance to oxygen diffusion, and myoglobin-facilitated diffusion are included. Parameter values are based on human skeletal muscle. The dependence of oxygen consumption on oxygen demand, perfusion, and capillary density are examined. When demand is moderate, the tissue is well oxygenated and consumption is slightly less than demand. When demand is high, capillary oxygen content declines rapidly with axial distance and radial oxygen transport is limited by diffusion resistance within the capillary and the tissue. Under these conditions, much of the tissue is hypoxic, consumption is substantially less than demand, and consumption is strongly dependent on capillary density. Predicted consumption rates are comparable with experimentally observed maximal rates of oxygen consumption.

  13. A Mediated BOD Biosensor Based on Immobilized B. Subtilis on Three-Dimensional Porous Graphene-Polypyrrole Composite

    Directory of Open Access Journals (Sweden)

    Jingfang Hu

    2017-11-01

    Full Text Available We have developed a novel mediated biochemical oxygen demand (BOD biosensor based on immobilized Bacillus subtilis (B. subtilis on three-dimensional (3D porous graphene-polypyrrole (rGO-PPy composite. The 3D porous rGO-PPy composite was prepared using hydrothermal method following with electropolymerization. Then the 3D porous rGO-PPy composite was used as a support for immobilizing negatively charged B. subtilis denoted as rGO-PPy-B through coordination and electrostatic interaction. Further, the prepared rGO-PPy-B was used as a microbial biofilm for establishing a mediated BOD biosensor with ferricyanide as an electronic acceptor. The indirect determination of BOD was performed by electrochemical measuring ferrocyanide generated from a reduced ferricyanide mediator using interdigited ultramicroelectrode array (IUDA as the working electrode. The experimental results suggested a good linear relationship between the amperometric responses and BOD standard concentrations from 4 to 60 mg/L, with a limit detection of 1.8 mg/L (S/N ≥ 3. The electrochemical measurement of real water samples showed a good agreement with the conventional BOD5 method, and the good anti-interference as well as the long-term stability were well demonstrated, indicating that the proposed mediated BOD biosensor in this study holds a potential practical application of real water monitoring.

  14. Impact simulation of shrimp farm effluent on BOD-DO in Setiu River

    Science.gov (United States)

    Chong, Michael Sueng Lock; Teh, Su Yean; Koh, Hock Lye

    2017-08-01

    Release of effluent from intensive aquaculture farms into a river can pollute the receiving river and exert negative impacts on the aquatic ecosystem. In this paper, we simulate the effects of effluent released from a marine shrimp aquaculture farm into Sg Setiu, focusing on two critical water quality parameters i.e. DO (dissolved oxygen) and BOD (biochemical oxygen demand). DO is an important constituent in a river in sustaining water quality, with levels of DO below 5 mg/L deemed undesirable. DO levels can be depressed by the presence of BOD and other organics that consume DO. Water quality simulations in conjunction with management of effluent treatment can suggest mitigation measures for reducing the adverse environmental impact. For this purpose, an in-house two-dimensional water quality simulation model codenamed TUNA-WQ will be used for these simulations. TUNA-WQ has been undergoing regular updates and improvements to broaden the applicability and to improve the robustness. Here, the model is calibrated and verified for simulation of DO and BOD dynamics in Setiu River (Sg Setiu). TUNA-WQ simulated DO and BOD in Setiu River due to the discharge from a marine shrimp aquaculture farm will be presented.

  15. Huge supply/demand increases seen in oxygenate forecasts

    International Nuclear Information System (INIS)

    Rhoades, A.K.

    1992-01-01

    Industry originally projected that oxygenate supply would not be able to meet the demand created by U.S. oxygenated and reformulated gasoline mandates. This paper reports that those projections have been reserved in two recent industry reports - one from Chemical Market Associates Inc. (CMAI) and one from Pace Consultants Inc. Pace's report, by Paulo Nery and Nathan Sims, predicts gasoline and oxygenates demand, and examines the role ethanol may play in changing those values. CMAI's report estimates captive supply and demand of butylenes and oxygenates. Oxygenates are entering the domestic gasoline market this winter as a result of the 1990 U.S. Clean Air Act Amendments. Methyl tertiary butyl ether (MTBE) is the most important oxygenate, although ethanol, ethyl tertiary butyl ether (ETBE), and tertiary amyl methyl ether (TAME) are gathering market strength. Ethanol's strength is derived from President Bush's ruling granting a waiver to reformulated gasoline containing ethanol. This waiver allows ethanol blends to have a vapor pressure 1 psi higher than other types of gasoline

  16. Correlating Biochemical and Chemical Oxygen Demand of Effluents

    African Journals Online (AJOL)

    F. K. Attiogbe1, Mary Glover-Amengor2 and K. T. Nyadziehe3

    There is also a slaughterhouse for animals (Sarfo-Afriyie, 1999). ... day period of the BOD test, the bacteria oxidized mainly the soluble organic ..... characteristics of the waste (effluent) not being constant (http://www.hach.com), and this is.

  17. Flame-Oxidized Stainless-Steel Anode as a Probe in Bioelectrochemical System-Based Biosensors to Monitor the Biochemical Oxygen Demand of Wastewater

    Directory of Open Access Journals (Sweden)

    Qiaochu Liang

    2018-02-01

    Full Text Available Biochemical oxygen demand (BOD is a widely used index of water quality in wastewater treatment; however, conventional measurement methods are time-consuming. In this study, we analyzed a novel flame-oxidized stainless steel anode (FO-SSA for use as the probe of bioelectrochemical system (BES-based biosensors to monitor the BOD of treated swine wastewater. A thinner biofilm formed on the FO-SSA compared with that on a common carbon-cloth anode (CCA. The FO-SSA was superior to the CCA in terms of rapid sensing; the response time of the FO-SSA to obtain the value of R2 > 0.8 was 1 h, whereas the CCA required 4 h. These results indicate that the FO-SSA offers better performance than traditional CCAs in BES biosensors and can be used to improve biomonitoring of wastewater.

  18. Removal of chemical oxygen demand from textile wastewater using a natural coagulant

    Energy Technology Data Exchange (ETDEWEB)

    Ramavandi, Bahman [Bushehr University of Medical Sciences, Bushehr (Iran, Islamic Republic of); Farjadfard, Sima [Islamic Azad University, Tehran (Iran, Islamic Republic of)

    2014-01-15

    A biomaterial was successfully synthesized from Plantago ovata by using an FeCl{sub 3}-induced crude extract (FCE). The potential of FCE to act as a natural coagulant was tested for the pretreatment of real textile wastewater. Tests were performed to evaluate the effects of FCE quantity, salt concentration, and wastewater pH on chemical oxygen demand (COD) reduction during a coagulation/flocculation process. Experimental results indicated that the wastewater could be effectively treated by using a coagulation/flocculation process, where the BOD{sub 5}/COD ratio of the effluent was improved to 0.48. A low coagulant dose, 1.5mg/L, achieved a high COD removal percentage, 89%, at operational conditions of neutral pH and room temperature. The experimental data revealed that the maximum COD removal occurred at water pH<8. Increasing the salt promoted the COD removal. The settling and filterability characteristics of the sludge were also studied. Scanning electron microscopy and energy dispersive spectroscopy studies were conducted to determine the sludge structure and composition, respectively. Overall, FCE as an eco-friendly biomaterial was revealed to be a very efficient coagulant and a promising option for the removal of COD from wastewaters.

  19. Sediment oxygen demand in the lower Willamette River, Oregon, 1994

    Science.gov (United States)

    Caldwell, James M.; Doyle, Micelis C.

    1995-01-01

    An investigation of sediment oxygen demand (SOD) at the interface of the stream and stream bed was performed in the lower Willamette River (river mile 51 to river mile 3) during August, 1994, as part of a cooperative project with the Oregon Department of Environmental Quality. The primary goals of the investigation were to measure the spatial variability of SOD in the lower Willamette River and to relate SOD to bottom-sediment characteristics.

  20. Use of one- and two-mediator systems for developing a BOD biosensor based on the yeast Debaryomyces hansenii.

    Science.gov (United States)

    Zaitseva, A S; Arlyapov, V A; Yudina, N Yu; Alferov, S V; Reshetilov, A N

    2017-03-01

    We investigated the use of one- and two-mediator systems in amperometric BOD biosensors (BOD, biochemical oxygen demand) based on the yeast Debaryomyces hansenii. Screening of nine mediators potentially capable of electron transfer - ferrocene, 1,1'-dimethylferrocene, ferrocenecarboxaldehyde, ferroceneacetonitrile, neutral red, 2,6-dichlorophenolindophenol, thionine, methylene blue and potassium ferricyanide - showed only ferrocene and neutral red to be efficient electron carriers for the eukaryotes studied. Two-mediator systems based on combinations of the investigated compounds were used to increase the efficiency of electron transfer. The developed two-mediator biosensors exceeded their one-mediator analogs by their characteristics. The most preferable two-mediator system for developing a BOD biosensor was a ferrocene-methylene blue combination that ensured a satisfactory long-time stability (43 days), selectivity, sensitivity (the lower limit of the determined BOD 5 concentrations, 2.5mg О 2 /dm 3 ) and speed (assay time for one sample, not greater than 10min) of BOD determination. Analysis of water samples showed that the use of a ferrocene-methylene blue two-mediator system and the yeast D. hansenii enabled registration of data that highly correlated with the results of the standard method (R=0.9913). Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Efeito da concentração inicial de oxigênio no coeficiente de aeração para experimentos de DBO de longo prazo - DOI: 10.4025/actascibiolsci.v25i2.1976 Effect of initial concentration of dissolved oxygen in aeration coefficient for long-term BOD experiments- DOI: 10.4025/actascibiolsci.v25i2.1976

    Directory of Open Access Journals (Sweden)

    Marcela Bianchessi da Cunha Santino

    2003-04-01

    Full Text Available Incubações de demanda bioquímica de oxigênio (DBO de longo prazo foram realizadas para determinar o coeficiente de aeração proveniente de experimentos de consumo de oxigênio. Os frascos de DBO foram preparados com água destilada e incubados no escuro e sob temperatura controlada (19,4ºC. Os frascos foram submetidos a dois tratamentos que foram baseados na concentração inicial de oxigênio dissolvido (OD: Tratamento 1 = 1,43mg L-1 e Tratamento 2 = 7,67mg L-1. As concentrações de OD foram determinadas com oxímetro durante 52 dias. Os resultados foram ajustados a um modelo cinético de primeira ordem. Os frascos de DBO apresentaram um incremento nas concentrações de OD para ambos os tratamentos e o coeficiente de aeração (ka foi de 0,065 dia-1. Os ajustes apontam dispersão nos valores de ka e a concentração inicial de OD nos frascos de DBO não interferiu no processo de aeração sendo um processo aleatórioLong-term incubations of biochemical oxygen demand (BOD were performed to determine the aeration coefficient derived from oxygen uptake experiments. The BOD bottles were prepared with distilled water and the incubation occurred in the dark, under controlled temperature (19.4ºC. The bottles were submitted to two different treatments based on the initial dissolved oxygen (DO concentrations (Treatment 1: 1.43mg L-1 and Treatment 2: 7.67mg L-1. The DO concentrations were measured with an OD meter during 52 days. The results were fitted to a first-order kinetics model. The BOD bottles showed an increase in DO concentration for both treatments and the mean aeration coefficient (ka was 0.065 a day-1. The fittings pointed to some dispersion in the ka values, and the initial concentration of DO in the BOD bottles does not interfere in the aeration process, being a random process

  2. A reduced-order adaptive neuro-fuzzy inference system model as a software sensor for rapid estimation of five-day biochemical oxygen demand

    Science.gov (United States)

    Noori, Roohollah; Safavi, Salman; Nateghi Shahrokni, Seyyed Afshin

    2013-07-01

    The five-day biochemical oxygen demand (BOD5) is one of the key parameters in water quality management. In this study, a novel approach, i.e., reduced-order adaptive neuro-fuzzy inference system (ROANFIS) model was developed for rapid estimation of BOD5. In addition, an uncertainty analysis of adaptive neuro-fuzzy inference system (ANFIS) and ROANFIS models was carried out based on Monte-Carlo simulation. Accuracy analysis of ANFIS and ROANFIS models based on both developed discrepancy ratio and threshold statistics revealed that the selected ROANFIS model was superior. Pearson correlation coefficient (R) and root mean square error for the best fitted ROANFIS model were 0.96 and 7.12, respectively. Furthermore, uncertainty analysis of the developed models indicated that the selected ROANFIS had less uncertainty than the ANFIS model and accurately forecasted BOD5 in the Sefidrood River Basin. Besides, the uncertainty analysis also showed that bracketed predictions by 95% confidence bound and d-factor in the testing steps for the selected ROANFIS model were 94% and 0.83, respectively.

  3. Estimates of Nitrogen, Phosphorus, Biochemical Oxygen Demand, and Fecal Coliforms Entering the Environment Due to Inadequate Sanitation Treatment Technologies in 108 Low and Middle Income Countries.

    Science.gov (United States)

    Fuhrmeister, Erica R; Schwab, Kellogg J; Julian, Timothy R

    2015-10-06

    Understanding the excretion and treatment of human waste (feces and urine) in low and middle income countries (LMICs) is necessary to design appropriate waste management strategies. However, excretion and treatment are often difficult to quantify due to decentralization of excreta management. We address this gap by developing a mechanistic, stochastic model to characterize phosphorus, nitrogen, biochemical oxygen demand (BOD), and fecal coliform pollution from human excreta for 108 LMICs. The model estimates excretion and treatment given three scenarios: (1) use of existing sanitation systems, (2) use of World Health Organization-defined "improved sanitation", and (3) use of best available technologies. Our model estimates that more than 10(9) kg/yr each of phosphorus, nitrogen and BOD are produced. Of this, 22(19-27)%, 11(7-15)%, 17(10-23)%, and 35 (23-47)% (mean and 95% range) BOD, nitrogen, phosphorus, and fecal coliforms, respectively, are removed by existing sanitation systems. Our model estimates that upgrading to "improved sanitation" increases mean removal slightly to between 17 and 53%. Under the best available technology scenario, only approximately 60-80% of pollutants are treated. To reduce impact of nutrient and microbial pollution on human and environmental health, improvements in both access to adequate sanitation and sanitation treatment efficiency are needed.

  4. The Influence of Ozonization For DO, BOD and Bacterial Growth in The Liquid Waste From Tanning Leather Industry

    International Nuclear Information System (INIS)

    M-Yazid; Aris-Bastianudin; Widdi-Usada

    2007-01-01

    The research of ozonization influence of dissolved oxygen (DO), biological oxygen demand (BOD) and the bacterial growth in the liquid waste from tanning leather industry has been done. The objectives of this research was to studied the influence of ozonization for decomposition process of the organic compound in these waste by indicator of BOD decreased, increased of DO and decomposer bacterial growth. The ozonization was carried out by time variation 0, 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165, 180, 195 and 210 minutes. Each samples of the waste has been ozonized keep in the sterile reaction tube for isolated of bacterial and the other keep in the bottle for BOD and DO measurement. These research results show that ozonization with 16.243 x 10 -4 mg/second debit for 3 hours can decreased of BOD were 19.61 %, and ozonization for 3.5 hours can increased of DO were 82.5%. The other hand, 3 hours ozonization can decreased of kind of bacterial growth were 80 %. (author)

  5. Artificial neural network modelling of biological oxygen demand in rivers at the national level with input selection based on Monte Carlo simulations.

    Science.gov (United States)

    Šiljić, Aleksandra; Antanasijević, Davor; Perić-Grujić, Aleksandra; Ristić, Mirjana; Pocajt, Viktor

    2015-03-01

    Biological oxygen demand (BOD) is the most significant water quality parameter and indicates water pollution with respect to the present biodegradable organic matter content. European countries are therefore obliged to report annual BOD values to Eurostat; however, BOD data at the national level is only available for 28 of 35 listed European countries for the period prior to 2008, among which 46% of data is missing. This paper describes the development of an artificial neural network model for the forecasting of annual BOD values at the national level, using widely available sustainability and economical/industrial parameters as inputs. The initial general regression neural network (GRNN) model was trained, validated and tested utilizing 20 inputs. The number of inputs was reduced to 15 using the Monte Carlo simulation technique as the input selection method. The best results were achieved with the GRNN model utilizing 25% less inputs than the initial model and a comparison with a multiple linear regression model trained and tested using the same input variables using multiple statistical performance indicators confirmed the advantage of the GRNN model. Sensitivity analysis has shown that inputs with the greatest effect on the GRNN model were (in descending order) precipitation, rural population with access to improved water sources, treatment capacity of wastewater treatment plants (urban) and treatment of municipal waste, with the last two having an equal effect. Finally, it was concluded that the developed GRNN model can be useful as a tool to support the decision-making process on sustainable development at a regional, national and international level.

  6. Tissue oxygen demand in regulation of the behavior of the cells in the vasculature.

    Science.gov (United States)

    Barvitenko, Nadezhda N; Aslam, Muhammad; Filosa, Jessica; Matteucci, Elena; Nikinmaa, Mikko; Pantaleo, Antonella; Saldanha, Carlota; Baskurt, Oguz K

    2013-08-01

    The control of arteriolar diameters in microvasculature has been in the focus of studies on mechanisms matching oxygen demand and supply at the tissue level. Functionally, important vascular elements include EC, VSMC, and RBC. Integration of these different cell types into functional units aimed at matching tissue oxygen supply with tissue oxygen demand is only achieved when all these cells can respond to the signals of tissue oxygen demand. Many vasoactive agents that serve as signals of tissue oxygen demand have their receptors on all these types of cells (VSMC, EC, and RBC) implying that there can be a coordinated regulation of their behavior by the tissue oxygen demand. Such functions of RBC as oxygen carrying by Hb, rheology, and release of vasoactive agents are considered. Several common extra- and intracellular signaling pathways that link tissue oxygen demand with control of VSMC contractility, EC permeability, and RBC functioning are discussed. © 2013 John Wiley & Sons Ltd.

  7. PREDICTION OF BOD AND COD OF A REFINERY WASTEWATER USING MULTILAYER ARTIFICIAL NEURAL NETWORKS

    Directory of Open Access Journals (Sweden)

    Eldon Raj Rene

    2008-06-01

    Full Text Available In the recent past, artificial neural networks (ANNs have shown the ability to learn and capture non-linear static or dynamic behaviour among variables based on the given set of data. Since the knowledge of internal procedure is not necessary, the modelling can take place with minimum previous knowledge about the process through proper training of the network. In the present study, 12 ANN based models were proposed to predict the Biochemical Oxygen Demand (BOD5 and Chemical Oxygen Demand (COD concentrations of wastewater generated from the effluent treatment plant of a petrochemical industry. By employing the standard back error propagation (BEP algorithm, the network was trained with 103 data points for water quality indices such as Total Suspended Solids (TSS, Total Dissolved Solids (TDS, Phenol concentration, Ammoniacal Nitrogen (AMN, Total Organic Carbon (TOC and Kjeldahl’s Nitrogen (KJN to predict BOD and COD. After appropriate training, the network was tested with a separate test data and the best model was chosen based on the sum square error (training and percentage average relative error (% ARE for testing. The results from this study reveal that ANNs can be accurate and efficacious in predicting unknown concentrations of water quality parameters through its versatile training process.

  8. Manual or automated measuring of antipsychotics' chemical oxygen demand.

    Science.gov (United States)

    Pereira, Sarah A P; Costa, Susana P F; Cunha, Edite; Passos, Marieta L C; Araújo, André R S T; Saraiva, M Lúcia M F S

    2018-05-15

    Antipsychotic (AP) drugs are becoming accumulated in terrestrial and aqueous resources due to their actual consumption. Thus, the search of methods for assessing the contamination load of these drugs is mandatory. The COD is a key parameter used for monitoring water quality upon the assessment of the effect of polluting agents on the oxygen level. Thus, the present work aims to assess the chemical oxygen demand (COD) levels of several typical and atypical antipsychotic drugs in order to obtain structure-activity relationships. It was implemented the titrimetric method with potassium dichromate as oxidant and a digestion step of 2h, followed by the measurement of remained unreduced dichromate by titration. After that, an automated sequential injection analysis (SIA) method was, also, used aiming to overcome some drawbacks of the titrimetric method. The results obtained showed a relationship between the chemical structures of antipsychotic drugs and their COD values, where the presence of aromatic rings and oxidable groups give higher COD values. It was obtained a good compliance between the results of the reference batch procedure and the SIA system, and the APs were clustered in two groups, with the values ratio between the methodologies, of 2 or 4, in the case of lower or higher COD values, respectively. The SIA methodology is capable of operating as a screening method, in any stage of a synthetic process, being also more environmentally friendly, and cost-effective. Besides, the studies presented open promising perspectives for the improvement of the effectiveness of pharmaceutical removal from the waste effluents, by assessing COD values. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. The Metropolis-Hastings algorithm, a handy tool for the practice of environmental model estimation : illustration with biochemical oxygen demand data

    Directory of Open Access Journals (Sweden)

    Franck Torre

    2001-02-01

    Full Text Available Environmental scientists often face situations where: (i stimulus-response relationships are non-linear; (ii data are rare or imprecise; (iii facts are uncertain and stimulus-responses relationships are questionable. In this paper, we focus on the first two points. A powerful and easy-to-use statistical method, the Metropolis-Hastings algorithm, allows the quantification of the uncertainty attached to any model response. This stochastic simulation technique is able to reproduce the statistical joint distribution of the whole parameter set of any model. The Metropolis-Hastings algorithm is described and illustrated on a typical environmental model: the biochemical oxygen demand (BOD. The aim is to provide a helpful guideline for further, and ultimately more complex, models. As a first illustration, the MH-method is also applied to a simple regression example to demonstrate to the practitioner the ability of the algorithm to produce valid results.

  10. Chapter A7. Section 7.0. Five-Day Biochemical Oxygen Demand

    Science.gov (United States)

    Delzer, Gregory C.; McKenzie, Stuart W.

    1999-01-01

    The presence of a sufficient concentration of dissolved oxygen is critical to maintaining the aquatic life and aesthetic quality of streams and lakes. Determinng how organic matter affects the concentration of dissolved oxygen (DO) in a stream or lake is integral to water-quality management. The decay of organic matter in water is measured as biochemical or chemical oxygen demand. This report describes the field protocols used by U.S. Geological Survey (USGS) personnel to determine the five-day test for biochemical oxygen demand.

  11. A comparative study of technologies for the continuous measurements of the biochemical demand for oxygen and toxicity of water; Estudio comparativo de tecnologias de medicion en continuo de la demanda bioquimica de oxigeno y de la toxicidad en aguas

    Energy Technology Data Exchange (ETDEWEB)

    Diez-Caballero Arnau, T.; Rodriguez Albalat, G.; Rosa de la Garcia, S.; Jimenez Bono, M.; Millan Navarro, C.; prats, R.; Serramia, A.; Miguel, S. de

    2002-07-01

    The Prevention and Integrated Control of Contamination Act (Ley de Prevencion y control Integrado de la Contaminacion) was passed by the Spanish parliament on 13 June. the basic purpose of this law is to prevent, reduce and control contamination of the atmosphere, water and soil caused by the most contaminating industrial activities. Public sector bodies and private companies in Spanish have been invited by the European Union to adopt new technologies in their production processes with a view to cutting down emissions, minimising or re-using waste, and pre-treating or purifying effluents. I t is therefore extremely appropriate to make available information on new tools of analysis that allow users to take preventive measures to reduce the impact their activity may have on the environment. A fundamental parameter in monitoring water is the Biological Demand for Oxygen (BOD). Various different chemical, physical and biological techniques have been developed to solve the problem of continuously monitoring the BOD and toxicity of water. This study carried out a comparative analysis of these techniques, describing the advantages and disadvantages of applying them to water quality control. At the present time it can be said that the BOD microbiosensor. Multisens 304 is the best available technology for monitoring this parameter. The articles tells us why. (Author) 8 refs.

  12. What is the Effect of Case-Based Learning on the Academic Achievement of Students on the Topic of "Biochemical Oxygen Demand?"

    Science.gov (United States)

    Günter, Tuğçe; Alpat, Sibel Kılınç

    2017-11-01

    The purpose of this study was to investigate the effect of the case-based learning (CBL) method used in "biochemical oxygen demand (BOD)," which is a topic taught in the environmental chemistry course, at Dokuz Eylul University, on the academic achievement and opinions of students. The research had a quasi-experimental design and the study group consisted of 4th and 5th grade students (N = 18) attending the Chemistry Teaching Program in a university in Izmir. The "Biochemical Oxygen Demand Achievement Test (BODAT)" and the structured interview form were used as data collection tools. The results of BODAT post-test showed the higher increase in the achievement scores of the experimental group may be an indication of the effectiveness of the CBL method in improving academic achievement in the relevant topic. In addition, the experimental and control group students had positive opinions regarding the method, the scenario, and the material. The students found the method, the scenario, and the material to be interesting, understandable/instructional, relatable with everyday life, suitable for the topic, and enhancing active participation.

  13. Enhancing Signal Output and Avoiding BOD/Toxicity Combined Shock Interference by Operating a Microbial Fuel Cell Sensor with an Optimized Background Concentration of Organic Matter

    Directory of Open Access Journals (Sweden)

    Yong Jiang

    2016-08-01

    Full Text Available In the monitoring of pollutants in an aquatic environment, it is important to preserve water quality safety. Among the available analysis methods, the microbial fuel cell (MFC sensor has recently been used as a sustainable and on-line electrochemical microbial biosensor for biochemical oxygen demand (BOD and toxicity, respectively. However, the effect of the background organic matter concentration on toxicity monitoring when using an MFC sensor is not clear and there is no effective strategy available to avoid the signal interference by the combined shock of BOD and toxicity. Thus, the signal interference by the combined shock of BOD and toxicity was systematically studied in this experiment. The background organic matter concentration was optimized in this study and it should be fixed at a high level of oversaturation for maximizing the signal output when the current change (ΔI is selected to correlate with the concentration of a toxic agent. When the inhibition ratio (IR is selected, on the other hand, it should be fixed as low as possible near the detection limit for maximizing the signal output. At least two MFC sensors operated with high and low organic matter concentrations and a response chart generated from pre-experiment data were both required to make qualitative distinctions of the four types of combined shock caused by a sudden change in BOD and toxicity.

  14. Efficiency of removal of bod5 and ss in sedimentation tanks and filters in wastewater treatment systems for coffee bean (Coffea arabica processing

    Directory of Open Access Journals (Sweden)

    Nelson Gutiérrez Guzmán

    2014-12-01

    Full Text Available n order to evaluate the current operating conditions of wastewater treatment systems of small scale coffee growers in the south of Huila a lab-scale prototype (S 1:25 was constructed. It was composed of both a sediment tank and a filter fit in series, simulating similar operating conditions used by coffee producers. Removal of biological oxygen demand (BOD5 and suspended solids (SS was performed in wastewater from coffee bean processing. A 23 factorial experimental design for the evaluation of the type of sedimentation tank, type of filter and hydraulic retention time (HRT in the sedimentation tank was employed. The results showed high removal efficiencies of suspended solid concentrations (more than 95%, and low removal efficiencies in BOD5 (about 20%. The combination of tank type 1 (square with a lower area, filter type 1 (upflow anaerobic filter – UAF and HRT of 30 hours had the highest removal efficiency.

  15. Sediment oxygen demand of wetlands in the oil sands region of north-eastern Alberta

    International Nuclear Information System (INIS)

    Slama, C.; Ciborowski, J.J.; Gardner Costa, J.

    2009-01-01

    Reclaimed land in the Alberta oil sands mining area contains both reference and oil sands process-affected wetlands constructed using varying sediment compositions. The sediments derived from oil sands process materials (OSPM) may alter the biochemical reactions that take place and affect the sediment oxygen demand (SOD), which is a key factor that contributes to oxygen depletion. This presentation reported on a study in which SOD was measured in a suite of constructed wetlands of different ages, with or without OSPM and topsoil. The purpose of the study was to clarify the role of SOD in wetland function and in the reclamation process. Dissolved oxygen loggers were inserted into dome-shaped chambers on the sediment to measure changes in oxygen demand. Complementary measurements of respiration (CO 2 elution) were used to quantify the biological sediment oxygen demand (BSOD) component of SOD. The chemical sediment oxygen demand (CSOD) was then determined by subtraction from SOD. Wetlands reclaimed using OSPM are expected to have a lower BSOD to CSOD ratio than reference wetlands. Residual ammonia in OSPM sediments may react with sulphate and bind phosphorus. This reduces phosphorus bioavailability and may impede submergent macrophyte growth. As such, wetlands affected by CSOD will have fewer submerged macrophytes than BSOD dominant wetlands.

  16. Nutrient regeneration and oxygen demand in Bering Sea continental shelf sediments

    Science.gov (United States)

    Rowe, Gilbert T.; Phoel, William C.

    1992-04-01

    Measurements of seabed oxygen demand and nutrient regeneration were made on continental shelf sediments in the southeast Bering Sea from 1 to 15 June 1981. The mean seabed oxygen demand was relatively modest (267 μM O 2 m -2 h -1), equivalent to a utilization of 60 mg organic carbon m -2 day -1. The seasonal build up of ammonium over the mid-shelf domain was generated at least in part by the bottom biota, as previously suggested ( WHITLEDGEet al., 1986 , Continental Shelf Research, 5, 109-132), but on the outer shelf nitrate replaced ammonium as the dominant inorganic nitrogen compound that was regenerated from the sediments. Comparison of oxygen consumption with the organic matter in sedimenting particulate matter (sampled with sediment traps) could imply that benthic processes were not accounting for the fate of considerable quantities of organic matter. Benthic oxygen demand rates, however, probably lag behind the input of the spring bloom to the bottom, thus extending the remineralization process out over time. Consumption by small microheterotrophs in the water column was also a likely sink, although shelf export and advective transport north were possible as well. Estimated nitrification rates in surface sediments could account for only a small fraction of the abrupt increase in nitrate observed in the water column over the shelf just prior to the spring bloom.

  17. An evaluation of solutions to moment method of biochemical oxygen ...

    African Journals Online (AJOL)

    This paper evaluated selected solutions of moment method in respect to Biochemical Oxygen Demand (BOD) kinetics with the aim of ascertain error free solution. Domestic - institutional wastewaters were collected two - weekly for three months from waste - stabilization ponds in Obafemi Awolowo University, Ile - Ife.

  18. Oxygen enriched air using membrane for palm oil wastewater treatment

    Directory of Open Access Journals (Sweden)

    Ramlah Mohd Tajuddin

    2002-11-01

    Full Text Available A research aimed to explore new method of aeration using oxygen enriched air performance on BOD reduction of palm oil wastewater was conducted. The oxygen enriched air was obtained from an Oxygen Enriched System (OES developed using asymmetric polysulfone hollow fiber membrane with composition consisting of PSF: 22%, DMAc: 31.8%, THF: 31.8%, EtOH: 14.4%. Palm oil wastewater samples were taken from facultative pond effluent. These samples were tested for its initial biochemical oxygen demand (BOD, total suspended solids (TSS, pH, conductivity, turbidity, dissolved oxygen (DO, suspended solids (SS, and total dissolved solids (TDS before being subjected to two modes of aeration system, that is diffused air and oxygen enriched air. These water quality concentrations were tested for every 20 minutes for two-hour period during the aeration process. Results of BOD, TSS, pH, conductivity, DO, SS and TDS concentrations against time of samples from the two modes of aeration were then compared. It was found that DO concentration achieved in oxygen enriched air aeration was better than aeration using diffused air system. Aeration using OES improve the DO concentration in the wastewater and thus improve the BOD reduction and also influence other physical characteristics of wastewater. This phenomenon indicates the advantage of using air with higher oxygen concentration for wastewater aeration instead of diffused air system.

  19. Sediment oxygen demand of wetlands in the oil sands region of northeastern Alberta

    International Nuclear Information System (INIS)

    Slama, C.; Gardner Costa, J.; Ciborowski, J.

    2010-01-01

    Sediment oxygen demand (SOD) can significantly influence the dissolved oxygen concentrations in shallow water bodies. This study discussed the types of sediments used to reclaim wetlands and their influence on SOD, successional processes, and ecosystem trajectories. The study hypothesized that oil sands process material (OSPM) affected wetlands would support cyanobacterial biofilms as opposed to submergent macrophytes as a result of insufficient phosphorus levels. SOD was assessed by monitoring dissolved oxygen concentrations within domes placed on the sediment surface for a 3-hour period. Gas flux and composition analyses were used to quantify the biological SOD components. Chemical SOD components were then determined by subtraction. Concentrations of phosphorus bioavailable to the macrophytes were estimated using plant root simulator probes. The study showed that OSPM wetlands exhibited higher chemical SOD and SOD than reference wetlands, and supported benthic biofilms as opposed to the submergent macrophyte communities typically found in northeastern Alberta wetlands.

  20. Sediment oxygen demand of wetlands in the oil sands region of northeastern Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Slama, C.; Gardner Costa, J.; Ciborowski, J. [Windsor Univ., ON (Canada)

    2010-07-01

    Sediment oxygen demand (SOD) can significantly influence the dissolved oxygen concentrations in shallow water bodies. This study discussed the types of sediments used to reclaim wetlands and their influence on SOD, successional processes, and ecosystem trajectories. The study hypothesized that oil sands process material (OSPM) affected wetlands would support cyanobacterial biofilms as opposed to submergent macrophytes as a result of insufficient phosphorus levels. SOD was assessed by monitoring dissolved oxygen concentrations within domes placed on the sediment surface for a 3-hour period. Gas flux and composition analyses were used to quantify the biological SOD components. Chemical SOD components were then determined by subtraction. Concentrations of phosphorus bioavailable to the macrophytes were estimated using plant root simulator probes. The study showed that OSPM wetlands exhibited higher chemical SOD and SOD than reference wetlands, and supported benthic biofilms as opposed to the submergent macrophyte communities typically found in northeastern Alberta wetlands.

  1. Lysimeter experiments to determine the ability of soil to reduce concentrations of BOD, available P and inorganic N in dirty water.

    Science.gov (United States)

    Brookman, S K E; Chadwick; Retter, A R

    2005-11-01

    Lysimeter experiments were conducted to determine the ability of different soils to reduce levels of biochemical oxygen demand (BOD) and concentrations of molybdate reactive phosphorus (MRP) and ammonium-N (NH4(+)-N) in dirty water and the impact of applications on nitrate leaching. An additional experiment investigated the effect of dirty water components on leaching quality. This information is required to assess the potential risk of dirty water applications on polluting groundwater and to assess the use of such soils in the development of treatment systems for dirty water. Intact and disturbed soil lysimeters, 0.5 and 1m deep were constructed from four soils; a coarse free-draining sandy loam, a sandy loam over soft sandstone, a calcareous silty clay over chalk and a sandy loam over granite. For the coarse free-draining sandy loam, lysimeters were also constructed from disturbed soil with and without the addition of lime, to assess if this could increase phosphorus immobilisation. Levels of BOD and concentrations of MRP, NH4(+)-N and nitrate (NO3(-)-N) of leachates were measured following dirty water applications at 2 and 8 mm day(-1) under laboratory conditions. Under the daily 2mm application, all soils were effective at treating dirty water, reducing concentrations of BOD, MRP and NH4(+)- N by > or = 98% but NO3(-)-N concentrations increased up to 80 mg l(-1) from the 0.5 m deep lysimeters of the sandy loam over granite. Soils were less effective at reducing levels of BOD, MRP and NH4(+)- N at the 8 mm daily rate of application, with maximum NO3(-)-N concentrations of leachates of 200 mg l(-1) from disturbed soils.

  2. Explorations on Temperature, Oxygen, Nutrients and Habitat Demands of Fish Species Found in River Coruh

    Directory of Open Access Journals (Sweden)

    Bilal Akbulut

    2009-04-01

    Full Text Available For the protection of our natural resources, fish species being economic and ecological richness of the natural in the basin of the Çoruh to know their request is extremely a vital important issue. In this study, temperature and oxygen demand, food and habitat of 18 fish species in six families found in river Çoruh assessed and discussed with the literature and database. Limiting the impact of water temperature on the reproductive, growth and nutrition emphasized. The fish species in the basin spawn at temperatures between 14-30°C according to database. Three species belonging to a family feed with animal food floating in the water. The species belonging to the other families more feed mixed with plant and animal foods diet in the floor or near the ground. Importance of their environmental demands has clarified for conservation and sustainable use of these fish species inhabiting in Çoruh River.

  3. Separating the effects of partial submergence and soil oxygen demand on plant physiology.

    Science.gov (United States)

    van Bodegom, Peter M; Sorrell, Brian K; Oosthoek, Annelies; Bakker, Chris; Aerts, Rien

    2008-01-01

    In wetlands, a distinct zonation of plant species composition occurs along moisture gradients, due to differential flooding tolerance of the species involved. However, "flooding" comprises two important, distinct stressors (soil oxygen demand [SOD] and partial submergence) that affect plant survival and growth. To investigate how these two flooding stressors affect plant performance, we executed a factorial experiment (water depth x SOD) for six plant species of nutrient-rich and nutrient-poor conditions, occurring along a moisture gradient in Dutch dune slacks. Physiological, growth, and biomass responses to changed oxygen availability were quantified for all species. The responses were consistent with field zonation, but the two stressors affected species differently. Increased SOD increased root oxygen deprivation, as indicated by either raised porosity or increased alcohol dehydrogenase (ADH) activity in roots of flood-intolerant species (Calamagrostis epigejos and Carex arenaria). While SOD affected root functioning, partial submergence tended more to reduce photosynthesis (as shown both by gas exchange and 13C assimilation), leaf dark respiration, 13C partitioning from shoots to roots, and growth of these species. These processes were especially affected if the root oxygen supply was depleted by a combination of flooding and increased SOD. In contrast, the most flood-tolerant species (Juncus subnodulosus and Typha latifolia) were unaffected by any treatment and maintained high internal oxygen concentrations at the shoot : root junction and low root ADH activity in all treatments. For these species, the internal oxygen transport capacity was well in excess of what was needed to maintain aerobic metabolism across all treatments, although there was some evidence for effects of SOD on their nitrogen partitioning (as indicated by 865N values) and photosynthesis. Two species intermediate in flooding tolerance (Carex nigra and Schoenus nigricans) responded more

  4. Research progress of on-line automatic monitoring of chemical oxygen demand (COD) of water

    Science.gov (United States)

    Cai, Youfa; Fu, Xing; Gao, Xiaolu; Li, Lianyin

    2018-02-01

    With the increasingly stricter control of pollutant emission in China, the on-line automatic monitoring of water quality is particularly urgent. The chemical oxygen demand (COD) is a comprehensive index to measure the contamination caused by organic matters, and thus it is taken as one important index of energy-saving and emission reduction in China’s “Twelve-Five” program. So far, the COD on-line automatic monitoring instrument has played an important role in the field of sewage monitoring. This paper reviews the existing methods to achieve on-line automatic monitoring of COD, and on the basis, points out the future trend of the COD on-line automatic monitoring instruments.

  5. Peroxone mineralization of chemical oxygen demand for direct potable water reuse: Kinetics and process control.

    Science.gov (United States)

    Wu, Tingting; Englehardt, James D

    2015-04-15

    Mineralization of organics in secondary effluent by the peroxone process was studied at a direct potable water reuse research treatment system serving an occupied four-bedroom, four bath university residence hall apartment. Organic concentrations were measured as chemical oxygen demand (COD) and kinetic runs were monitored at varying O3/H2O2 dosages and ratios. COD degradation could be accurately described as the parallel pseudo-1st order decay of rapidly and slowly-oxidizable fractions, and effluent COD was reduced to below the detection limit (<0.7 mg/L). At dosages ≥4.6 mg L(-1) h(-1), an O3/H2O2 mass ratio of 3.4-3.8, and initial COD <20 mg/L, a simple first order decay was indicated for both single-passed treated wastewater and recycled mineral water, and a relationship is proposed and demonstrated to estimate the pseudo-first order rate constant for design purposes. At this O3/H2O2 mass ratio, ORP and dissolved ozone were found to be useful process control indicators for monitoring COD mineralization in secondary effluent. Moreover, an average second order rate constant for OH oxidation of secondary effluent organics (measured as MCOD) was found to be 1.24 × 10(7) ± 0.64 × 10(7) M(-1) S(-1). The electric energy demand of the peroxone process is estimated at 1.73-2.49 kW h electric energy for removal of one log COD in 1 m(3) secondary effluent, comparable to the energy required for desalination of medium strength seawater. Advantages/disadvantages of the two processes for municipal wastewater reuse are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Chemometrics-assisted spectrophotometry method for the determination of chemical oxygen demand in pulping effluent.

    Science.gov (United States)

    Chen, Honglei; Chen, Yuancai; Zhan, Huaiyu; Fu, Shiyu

    2011-04-01

    A new method has been developed for the determination of chemical oxygen demand (COD) in pulping effluent using chemometrics-assisted spectrophotometry. Two calibration models were established by inducing UV-visible spectroscopy (model 1) and derivative spectroscopy (model 2), combined with the chemometrics software Smica-P. Correlation coefficients of the two models are 0.9954 (model 1) and 0.9963 (model 2) when COD of samples is in the range of 0 to 405 mg/L. Sensitivities of the two models are 0.0061 (model 1) and 0.0056 (model 2) and method detection limits are 2.02-2.45 mg/L (model 1) and 2.13-2.51 mg/L (model 2). Validation experiment showed that the average standard deviation of model 2 was 1.11 and that of model 1 was 1.54. Similarly, average relative error of model 2 (4.25%) was lower than model 1 (5.00%), which indicated that the predictability of model 2 was better than that of model 1. Chemometrics-assisted spectrophotometry method did not need chemical reagents and digestion which were required in the conventional methods, and the testing time of the new method was significantly shorter than the conventional ones. The proposed method can be used to measure COD in pulping effluent as an environmentally friendly approach with satisfactory results.

  7. Chemical Oxygen Demand abatement in sewage using Micro-Aeration Enhanced Ecological Floating Bed

    Science.gov (United States)

    Shi, Hongle; Zhou, Gaofeng; Liu, Yiqing; Tan, Jiancong; Fu, Yongsheng

    2018-02-01

    The traditional ecological floating bed combined with micro-aeration system and artificial medium was developed for the removal of contaminants and remediation of surface water. This micro-aeration enhanced ecological floating bed (MAEEFB) consisted of aeration unit, microbial processing unit and aquatic plant unit. Batch experiments were conducted in different operating conditions on the removal of chemical oxygen demand (COD) in the sewage using MAEEFB. The removal rate of COD by MAEEFB, enhanced ecological floating bed (EEFB) and traditional ecological floating bed (TEFB) in the same reaction conditions was 59.2%, 56.9% and 30.6%, respectively, indicating that the combination of micro-aeration system and artificial medium could enhance the removal efficiency of COD in TEFB. In MAEEFB, the aeration intensity should be designed reasonablely considering both treatment efficiency and operation cost. Only increasing the specific surface area of the packing cannot effectively improve the purification efficiency of water. Factors like packing material, ability of intercepting organics and complicated extent of microorganisms attaching on the packing should also be considered.

  8. Chemical oxygen demand reduction in coffee wastewater through chemical flocculation and advanced oxidation processes

    Institute of Scientific and Technical Information of China (English)

    ZAYAS Pérez Teresa; GEISSLER Gunther; HERNANDEZ Fernando

    2007-01-01

    The removal of the natural organic matter present in coffee processing wastewater through chemical coagulation-flocculatio and advanced oxidation processes(AOP)had been studied.The effectiveness of the removal of natural organic matter using commercial flocculants and UV/H202,UVO3 and UV/H-H202/O3 processes was determined under acidic conditions.For each of these processes,different operational conditions were explored to optimize the treatment efficiency of the coffee wastewater.Coffee wastewater is characterized by a high chemical oxygen demand(COD)and low total suspended solids.The outcomes of coffee wastewater reeatment using coagulation-flocculation and photodegradation processes were assessed in terms of reduction of COD,color,and turbidity.It was found that a reductiOn in COD of 67%could be realized when the coffee wastewater was treated by chemical coagulation-flocculatlon witll lime and coagulant T-1.When coffee wastewater was treated by coagulation-flocculation in combination with UV/H202,a COD reduction of 86%was achieved,although only after prolonged UV irradiation.Of the three advanced oxidation processes considered,UV/H202,uv/03 and UV/H202/03,we found that the treatment with UV/H2O2/O3 was the most effective,with an efficiency of color,turbidity and further COD removal of 87%,when applied to the flocculated coffee wastewater.

  9. Exercise Training Reduces Peripheral Arterial Stiffness and Myocardial Oxygen Demand in Young Prehypertensive Subjects

    Science.gov (United States)

    2013-01-01

    BACKGROUND Large artery stiffness is a major risk factor for the development of hypertension and cardiovascular disease. Persistent prehypertension accelerates the progression of arterial stiffness. METHODS Forty-three unmedicated prehypertensive (systolic blood pressure (SBP) = 120–139mm Hg or diastolic blood pressure (DBP) = 80–89mm Hg) men and women and 15 normotensive time-matched control subjects (NMTCs; n = 15) aged 18–35 years of age met screening requirements and participated in the study. Prehypertensive subjects were randomly assigned to a resistance exercise training (PHRT; n = 15), endurance exercise training (PHET; n = 13) or time-control group (PHTC; n = 15). Treatment groups performed exercise training 3 days per week for 8 weeks. Pulse wave analysis, pulse wave velocity (PWV), and central and peripheral blood pressures were evaluated before and after exercise intervention or time-matched control. RESULTS PHRT and PHET reduced resting SBP by 9.6±3.6mm Hg and 11.9±3.4mm Hg, respectively, and DBP by 8.0±5.1mm Hg and 7.2±3.4mm Hg, respectively (P endurance exercise alone effectively reduce peripheral arterial stiffness, central blood pressures, augmentation index, and myocardial oxygen demand in young prehypertensive subjects. PMID:23736111

  10. Exercise training reduces peripheral arterial stiffness and myocardial oxygen demand in young prehypertensive subjects.

    Science.gov (United States)

    Beck, Darren T; Martin, Jeffrey S; Casey, Darren P; Braith, Randy W

    2013-09-01

    Large artery stiffness is a major risk factor for the development of hypertension and cardiovascular disease. Persistent prehypertension accelerates the progression of arterial stiffness. Forty-three unmedicated prehypertensive (systolic blood pressure (SBP) = 120-139 mm Hg or diastolic blood pressure (DBP) = 80-89 mm Hg) men and women and 15 normotensive time-matched control subjects (NMTCs; n = 15) aged 18-35 years of age met screening requirements and participated in the study. Prehypertensive subjects were randomly assigned to a resistance exercise training (PHRT; n = 15), endurance exercise training (PHET; n = 13) or time-control group (PHTC; n = 15). Treatment groups performed exercise training 3 days per week for 8 weeks. Pulse wave analysis, pulse wave velocity (PWV), and central and peripheral blood pressures were evaluated before and after exercise intervention or time-matched control. PHRT and PHET reduced resting SBP by 9.6±3.6mm Hg and 11.9±3.4mm Hg, respectively, and DBP by 8.0±5.1mm Hg and 7.2±3.4mm Hg, respectively (P endurance exercise alone effectively reduce peripheral arterial stiffness, central blood pressures, augmentation index, and myocardial oxygen demand in young prehypertensive subjects.

  11. Integrating the Fenton's Process with Biofiltration by to Reduce Chemical Oxygen Demand of Winery Effluents.

    Science.gov (United States)

    Pipolo, Marco; Martins, Rui C; Quinta-Ferreira, Rosa M; Costa, Raquel

    2017-03-01

    The discharge of poorly decontaminated winery wastewater remains a serious environmental problem in many regions, and the industry is welcoming improved treatment methods. Here, an innovative decontamination approach integrating Fenton's process with biofiltration by Asian clams is proposed. The potential of this approach was assessed at the pilot scale using real effluent and by taking an actual industrial treatment system as a benchmark. Fenton peroxidation was observed to remove 84% of the effluent's chemical oxygen demand (COD), reducing it to 205 mg L. Subsequent biofiltration decreased the effluent's COD to approximately zero, well below the legal discharge limit of 150 mg L, in just 3 d. The reduction of the effluent's organic load through Fenton's process did not decrease its toxicity toward , but the effluent was much less harmful after biofiltration. The performance of the treatment proposed exceeded that of the integrated Fenton's process-sequencing batch reactor design implemented in the winery practice, where a residence time of around 10 d in the biological step typically results in 80 to 90% of COD removal. The method proposed is effective and compatible with typical winery budgets and potentially contributes to the management of a nuisance species. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  12. Low cost chemical oxygen demand sensor based on electrodeposited nano-copper film

    Directory of Open Access Journals (Sweden)

    Hamdy H. Hassan

    2018-02-01

    Full Text Available A commercially available copper electrical cable and pure Cu disk were used as substrates for the electrodeposition of copper nanoparticles (nano-Cu. The surface morphology of the prepared nano-Cu/Cu electrodes was investigated by scanning electron microscope (SEM and energy dispersive X-ray spectrometer (EDX. The bare copper substrates and the nano-copper modified electrodes were utilized and optimized for electrochemical assay of chemical oxygen demand (COD using glycine as a standard. A comparison was made among the four electrodes (i.e., bare and nano-Cu coated copper cable and pure copper disk as potential COD sensors. The oxidation behavior of glycine was investigated on the surface of the prepared sensors using linear sweep voltammetry (LSV. The results indicate significant enhancement of the electrochemical oxidation of glycine by the deposited nano-Cu. The effects of different deposition parameters, such as Cu2+ concentration, deposition potential, deposition time, pH, and scan rate on the response of the prepared sensors were investigated. Under optimized conditions, the optimal nano-Cu based COD sensor exhibited a linear range of 2–595 mg/L, lower limit of detection (LOD as low as 1.07 mg/L (S/N = 3. The developed method exhibited high tolerance level to Cl− ion where 1.0 M Cl− exhibited minimal influence. The sensor was utilized for the detection of COD in different real water samples. The results obtained were validated using the standard dichromate method.

  13. Study of the degradation performance (TOC, BOD, and toxicity) of bisphenol A by the photo-Fenton process.

    Science.gov (United States)

    Pérez-Moya, M; Kaisto, T; Navarro, M; Del Valle, L J

    2017-03-01

    Degradation of bisphenol A (BPA, 0.5 L, 30 mg L -1 ) was studied by photo-Fenton treatment, while Fenton reagents were variables. The efficiency of the degradation process was evaluated by the reduction of total organic carbon (TOC), the biochemical oxygen demand (BOD), and toxicity. For toxicity analysis, bacterial methods were found infeasible, but the in vitro assay of VERO cells culture was successfully applied. Experiments according to a 2 2 design of experiments (DOE) with star points and three center points for statistical validity allowed selecting those process conditions (Fe(II) and H 2 O 2 load) that maximized the process performance. Photo-Fenton process effectively eliminated BPA and partly degraded its by-products (residual TOC TOC = 92 %) was attained. Toxicity was also detected to 50 % of cellular mortality even at long reaction times. However, 40.25 mg L -1 of H 2 O 2 decreased residual TOC to 70 % while cell mortality decreased down to 25 %. With more H 2 O 2 , the residual TOC decreased down to 15 % but cell mortality remained within the 20-25 % level. Photo-Fenton increased the biodegradability and reduced the toxicity of the studied sample.

  14. Characterization of water quality and simulation of temperature, nutrients, biochemical oxygen demand, and dissolved oxygen in the Wateree River, South Carolina, 1996-98

    Science.gov (United States)

    Feaster, Toby D.; Conrads, Paul

    2000-01-01

    In May 1996, the U.S. Geological Survey entered into a cooperative agreement with the Kershaw County Water and Sewer Authority to characterize and simulate the water quality in the Wateree River, South Carolina. Longitudinal profiling of dissolved-oxygen concentrations during the spring and summer of 1996 revealed dissolved-oxygen minimums occurring upstream from the point-source discharges. The mean dissolved-oxygen decrease upstream from the effluent discharges was 2.0 milligrams per liter, and the decrease downstream from the effluent discharges was 0.2 milligram per liter. Several theories were investigated to obtain an improved understanding of the dissolved-oxygen dynamics in the upper Wateree River. Data suggest that the dissolved-oxygen concentration decrease is associated with elevated levels of oxygen-consuming nutrients and metals that are flowing into the Wateree River from Lake Wateree. Analysis of long-term streamflow and water-quality data collected at two U.S. Geological Survey gaging stations suggests that no strong correlation exists between streamflow and dissolved-oxygen concentrations in the Wateree River. However, a strong negative correlation does exist between dissolved-oxygen concentrations and water temperature. Analysis of data from six South Carolina Department of Health and Environmental Control monitoring stations for 1980.95 revealed decreasing trends in ammonia nitrogen at all stations where data were available and decreasing trends in 5-day biochemical oxygen demand at three river stations. The influence of various hydrologic and point-source loading conditions on dissolved-oxygen concentrations in the Wateree River were determined by using results from water-quality simulations by the Branched Lagrangian Transport Model. The effects of five tributaries and four point-source discharges were included in the model. Data collected during two synoptic water-quality samplings on June 23.25 and August 11.13, 1997, were used to calibrate

  15. Studies on the kinetics and intraparticle diffusivities of BOD, colour ...

    African Journals Online (AJOL)

    EJIRO

    The kinetics and intraparticle diffusivities of BOD, TSS and colour reduction from palm oil mill effluent (POME) using ... discharged (Asia et al., 2006). The oil palm ... biological treatment methods, anaerobic digestion is often the most ... and lower capital cost. ... was then rinsed with distilled water and air dried, ready for the.

  16. Studies on the kinetics and intraparticle diffusivities of BOD, colour ...

    African Journals Online (AJOL)

    Therefore, this study reveals that boiler fly ash can effectively be used as an adsorbent for POME treatment and also established the kinetic and mechanisms of the sorption process. Also, the results of this study could serve as effective design parameters for a treatment plant to further reduce BOD, colour and TSS from ...

  17. Incorporation of oxygen contribution by plant roots into classical dissolved oxygen deficit model for a subsurface flow treatment wetland.

    Science.gov (United States)

    Bezbaruah, Achintya N; Zhang, Tian C

    2009-01-01

    It has been long established that plants play major roles in a treatment wetland. However, the role of plants has not been incorporated into wetland models. This study tries to incorporate wetland plants into a biochemical oxygen demand (BOD) model so that the relative contributions of the aerobic and anaerobic processes to meeting BOD can be quantitatively determined. The classical dissolved oxygen (DO) deficit model has been modified to simulate the DO curve for a field subsurface flow constructed wetland (SFCW) treating municipal wastewater. Sensitivities of model parameters have been analyzed. Based on the model it is predicted that in the SFCW under study about 64% BOD are degraded through aerobic routes and 36% is degraded anaerobically. While not exhaustive, this preliminary work should serve as a pointer for further research in wetland model development and to determine the values of some of the parameters used in the modified DO deficit and associated BOD model. It should be noted that nitrogen cycle and effects of temperature have not been addressed in these models for simplicity of model formulation. This paper should be read with this caveat in mind.

  18. Serum Tumor Necrosis Factor-alpha associates with Myocardial Oxygen Demand and Exercise Tolerance in Postmenopausal Women.

    Science.gov (United States)

    Carter, Stephen J; Bryan, David R; Neumeier, William H; Glasser, Stephen P; Hunter, Gary R

    2018-01-01

    The functional implications of serum tumor necrosis factor-alpha (TNF-α), a marker of oxidative stress, on hemodynamic parameters at rest and during physical exertion are unclear. The aims of this investigation were to examine the independent associations of TNF-α on myocardial oxygen demand at rest and during submaximal exercise, while also evaluating the association of TNF-α on exercise tolerance. Forty, postmenopausal women, provided blood samples and completed a modified-Balke protocol to measure maximal oxygen uptake (VO 2max ). Large artery compliance was measured by pulse contour analyses while rate-pressure product (RPP), an index of myocardial oxygen demand, was measured at rest and during two submaximal workloads (i.e., ≈55% and ≈75% VO 2max ). RPP was calculated by dividing the product of heart rate and systolic blood pressure (via auscultation) by 100. Exercise tolerance corresponded with the cessation of the graded exercise test. During higher-intensity exertion, ≈75% VO 2max , multiple linear regression revealed a positive association ( r = 0.43; p = 0.015) between TNF-α and RPP while adjusting for maximal heart rate, VO 2max , large artery compliance, and percent body fat. Path analyses revealed a significant indirect effect of large artery compliance on exercise tolerance through TNF-α, β = 0.13, CI [0.03, 0.35], indicating greater levels of TNF-α associated with poorer exercise tolerance. These data suggest TNF-α independently associates with myocardial oxygen demand during physical exertion, thus highlighting the utility of higher-intensity efforts to expose important phenomena not apparent at rest. TNF-α also appears to be indirectly associated with the link between large artery compliance and exercise tolerance.

  19. Application of Microbial BOD Sensors in Marine Monitoring

    Institute of Scientific and Technical Information of China (English)

    张悦; 王建龙; 李花子; 施汉昌; 竺建荣

    2001-01-01

    A strain of yeast, which can endure high osmotic pressure, is employed for the sensitive material of the microbial BOD sensor. Two immobilization methods are used, I.e. Calcium alginate gel be ads and PV A gel beads. The results show that the PVA gel beads is better. The influences of osmosis and heavy metal ions on the yeast entrapped in the PVA gel beads are also studied in the experiment.

  20. Respirometric oxygen demand determinations of laboratory- and field-scale biofilters

    International Nuclear Information System (INIS)

    Rho, D.; Mercier, P.; Jette, J.F.

    1995-01-01

    A biofiltration experiment operated at three inlet concentrations (425, 830, and 1,450 mg m -3 ), showed that the specific oxygen consumption rate was highly correlated (R = 0.938, n = 23) with the toluene elimination capacity. A radiorespirometric test was found to be more sensitive and appropriate for the field-scale biofilter treating gasoline vapors

  1. Nitrogen and chemical oxygen demand removal from septic tank wastewater in subsurface flow constructed wetlands: substrate (cation exchange capacity) effects.

    Science.gov (United States)

    Collison, Robert S; Grismer, Mark E

    2014-04-01

    The current article focuses on chemical oxygen demand (COD) and nitrogen (ammonium and nitrate) removal performance from synthetic human wastewater as affected by different substrate rocks having a range of porosities and cation exchange capacities (CECs). The aggregates included lava rock, lightweight expanded shale, meta-basalt (control), and zeolite. The first three had CECs of 1 to 4 mequiv/100 gm, whereas the zeolite CEC was much greater (-80 mequiv/100 gm). Synthetic wastewater was gravity fed to each constructed wetland system, resulting in a 4-day retention time. Effluent samples were collected, and COD and nitrogen species concentrations measured regularly during four time periods from November 2008 through June 2009. Chemical oxygen demand and nitrogen removal fractions were not significantly different between the field and laboratory constructed wetland systems when corrected for temperature. Similarly, overall COD and nitrogen removal fractions were practically the same for the aggregate substrates. The important difference between aggregate effects was the zeolite's ammonia removal process, which was primarily by adsorption. The resulting single-stage nitrogen removal process may be an alternative to nitrification and denitrification that may realize significant cost savings in practice.

  2. Quantum dots assisted photocatalysis for the chemiluminometric determination of chemical oxygen demand using a single interface flow system

    Energy Technology Data Exchange (ETDEWEB)

    Silvestre, Cristina I.C.; Frigerio, Christian [Requimte, Department of Chemistry, Faculty of Pharmacy, Porto University, Rua Anibal Cunha 164, 4099-030, Porto (Portugal); Santos, Joao L.M., E-mail: joaolms@ff.up.pt [Requimte, Department of Chemistry, Faculty of Pharmacy, Porto University, Rua Anibal Cunha 164, 4099-030, Porto (Portugal); Lima, Jose L.F.C. [Requimte, Department of Chemistry, Faculty of Pharmacy, Porto University, Rua Anibal Cunha 164, 4099-030, Porto (Portugal)

    2011-08-12

    Highlights: {yields} A novel flow method for the determination of chemical oxygen demand is proposed. {yields} CdTe nanocrystals are irradiated with UV light to generate strong oxidizing species. {yields} Reactive species promote a fast catalytic degradation of organic matter. {yields} Luminol is used as a chemiluminescence probe for indirect COD assessment. {yields} A single interface flow system was implemented to automate the assays. - Abstract: A novel flow method for the determination of chemical oxygen demand (COD) is proposed in this work. It relies on the combination of a fully automated single interface flow system, an on-line UV photocatalytic unit and quantum dot (QD) nanotechnology. The developed approach takes advantage of CdTe nanocrystals capacity to generate strong oxidizing species upon irradiation with UV light, which fostered a fast catalytic degradation of the organic compounds. Luminol was used as a chemiluminescence (CL) probe for indirect COD assessment, since it is easily oxidized by the QD generated species yielding a strong CL emission that is quenched in the presence of the organic matter. The proposed methodology allowed the determination of COD concentrations between 1 and 35 mg L{sup -1}, with good precision (R.S.D. < 1.1%, n = 3) and a sampling frequency of about 33 h{sup -1}. The procedure was applied to the determination of COD in wastewater certified reference materials and the obtained results showed an excellent agreement with the certified values.

  3. Chromium (VI) biosorption and removal of chemical oxygen demand by Spirulina platensis from wastewater-supplemented culture medium.

    Science.gov (United States)

    Magro, Clinei D; Deon, Maitê C; De Rossi, Andreia; Reinehr, Christian O; Hemkemeier, Marcelo; Colla, Luciane M

    2012-01-01

    The inappropriate discharge of wastewater containing high concentrations of toxic metals is a serious threat to the environment. Given that the microalga Spirulina platensis has demonstrated a capacity for chromium VI (Cr (VI) biosorption, we assessed the ideal concentration of chromium-containing wastewater required for maximum removal of Cr (VI) and chemical oxygen demand (COD) from the environment by using this microalga. The Paracas and Leb-52 strains of S. platensis, with initial wastewater concentrations of 0%, 12.5%, 25%, and 50%, were cultured in Zarrouk medium diluted to 50% under controlled air, temperature, and lighting conditions. The cultures were maintained for 28 days, and pH, biomass growth, COD, and Cr (VI) were assessed. The wastewater concentration influenced microalgal growth, especially at high concentrations. Removal of 82.19% COD and 60.92% Cr (VI) was obtained, but the COD removal was greater than the Cr (VI) removal in both strains of S. platensis.

  4. Esmolol acutely alters oxygen supply-demand balance in exercising muscles of healthy humans.

    Science.gov (United States)

    Proctor, David N; Luck, J Carter; Maman, Stephan R; Leuenberger, Urs A; Muller, Matthew D

    2018-04-01

    Beta-adrenoreceptor antagonists (β blockers) reduce systemic O 2 delivery and blood pressure (BP) during exercise, but the subsequent effects on O 2 extraction within the active limb muscles are unknown. In this study, we examined the effects of the fast-acting, β 1 selective blocker esmolol on systemic hemodynamics and leg muscle O 2 saturation (near infrared spectroscopy, NIRS) during submaximal leg ergometry. Our main hypothesis was that esmolol would augment exercise-induced reductions in leg muscle O 2 saturation. Eight healthy adults (6 men, 2 women; 23-67 year) performed light and moderate intensity bouts of recumbent leg cycling before (PRE), during (β 1 -blocked), and 45 min following (POST) intravenous infusion of esmolol. Oxygen uptake, heart rate (HR), BP, and O 2 saturation (SmO 2 ) of the vastus lateralis (VL) and medial gastrocnemius (MG) muscles were measured continuously. Esmolol attenuated the increases in HR and systolic BP during light (-12 ± 9 bpm and -26 ± 12 mmHg vs. PRE) and moderate intensity (-20 ± 10 bpm and -40 ± 18 mmHg vs. PRE) cycling (all P Exercise-induced reductions in SmO 2 occurred to a greater extent during the β 1 -blockade trial in both the VL (P = 0.001 vs. PRE) and MG muscles (P = 0.022 vs. PRE). HR, SBP and SmO 2 were restored during POST (all P exercising muscles of healthy humans. © 2018 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

  5. Oxygen demand for the stabilization of the organic fraction of municipal solid waste in passively aerated bioreactors

    International Nuclear Information System (INIS)

    Kasinski, Slawomir; Wojnowska-Baryla, Irena

    2014-01-01

    Highlights: • The use of an passively aerated reactor enables effective stabilization of OFMSW. • Convective air flow does not inhibit the aerobic stabilization of waste. • The use of an passively aerated reactor reduces the heat loss due to convection. • The volume of supplied air exceeds 1.7–2.88 times the microorganisms demand. - Abstract: Conventional aerobic waste treatment technologies require the use of aeration devices that actively transport air through the stabilized waste mass, which greatly increases operating costs. In addition, improperly operated active aeration systems, may have the adverse effect of cooling the stabilized biomass. Because active aeration can be a limiting factor for the stabilization process, passive aeration can be equally effective and less expensive. Unfortunately, there are few reports documenting the use of passive aeration systems in municipal waste stabilization. There have been doubts raised as to whether a passive aeration system provides enough oxygen to the organic matter mineralization processes. In this paper, the effectiveness of aeration during aerobic stabilization of four different organic fractions of municipal waste in a reactor with an integrated passive ventilation system and leachate recirculation was analyzed. For the study, four fractions separated by a rotary screen were chosen. Despite the high temperatures in the reactor, the air flow rate was below 0.016 m 3 /h. Using Darcy’s equation, theoretical values of the air flow rate were estimated, depending on the intensity of microbial metabolism and the amount of oxygen required for the oxidation of organic compounds. Calculations showed that the volume of supplied air exceeded the microorganisms demand for oxidation and endogenous activity by 1.7–2.88-fold

  6. Correlation of COD and BOD of domestic wastewater with the power output of bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Khan, A M; Ataullah,; Shaheen, A; Ahmad, I; Malik, F; Shahid, H A [Federal Urdu University of Arts, Science and Technology, Gulshan-e-Iqbal Campus, University Road, Karachi-75300 (Pakistan). Research Laboratory of Bioenergy, Department of Chemistry

    2011-04-15

    This research article deals with the studies on the development of the correlation of COD, BOD, and BOD/sub 5/ of domestic wastewater (DWW), and fermented domestic wastewater (FDWW) with the power output of the microbial fuel cell (MFC). The fermentation of DWW was carried out with yeast (Saccharomyces cerevisiae), and yogurt bacteria (Streptococcus lactis) to produce biohydrogen which was converted to the electrical energy through the development of microbial fuel cell (MFC). The values of COD, BOD, and BOD/sub 5/ for yogurt fermented domestic wastewater (Yogurt-FDWW) were found to be greater than the values of yeast fermented domestic wastewater (Yeast-FDWW). The power output of DWW and FDWW was increased with the increase in COD, BOD and BOD/sub 5/ values. The main objective of this article is to develop the renewable alternative of fossil fuels which are the major cause of global warming and global pollution. (author)

  7. Correlation of COD and BOD of domestic wastewater with the power output of bioreactor

    International Nuclear Information System (INIS)

    Khan, A.M.; Ataullah; Shaheen, A.; Ahmad, I.; Malik, F.; Shahid, H.A.

    2011-01-01

    This research article deals with the studies on the development of the correlation of COD, BOD, and BOD/sub 5/ of domestic wastewater (DWW), and fermented domestic wastewater (FDWW) with the power output of the microbial fuel cell (MFC). The fermentation of DWW was carried out with yeast (Saccharomyces cerevisiae), and yogurt bacteria (Streptococcus lactis) to produce biohydrogen which was converted to the electrical energy through the development of microbial fuel cell (MFC). The values of COD, BOD, and BOD/sub 5/ for yogurt fermented domestic wastewater (Yogurt-FDWW) were found to be greater than the values of yeast fermented domestic wastewater (Yeast-FDWW). The power output of DWW and FDWW was increased with the increase in COD, BOD and BOD/sub 5/ values. The main objective of this article is to develop the renewable alternative of fossil fuels which are the major cause of global warming and global pollution. (author)

  8. An integrated mathematical model for chemical oxygen demand (COD) removal in moving bed biofilm reactors (MBBR) including predation and hydrolysis.

    Science.gov (United States)

    Revilla, Marta; Galán, Berta; Viguri, Javier R

    2016-07-01

    An integrated mathematical model is proposed for modelling a moving bed biofilm reactor (MBBR) for removal of chemical oxygen demand (COD) under aerobic conditions. The composite model combines the following: (i) a one-dimensional biofilm model, (ii) a bulk liquid model, and (iii) biological processes in the bulk liquid and biofilm considering the interactions among autotrophic, heterotrophic and predator microorganisms. Depending on the values for the soluble biodegradable COD loading rate (SCLR), the model takes into account a) the hydrolysis of slowly biodegradable compounds in the bulk liquid, and b) the growth of predator microorganisms in the bulk liquid and in the biofilm. The integration of the model and the SCLR allows a general description of the behaviour of COD removal by the MBBR under various conditions. The model is applied for two in-series MBBR wastewater plant from an integrated cellulose and viscose production and accurately describes the experimental concentrations of COD, total suspended solids (TSS), nitrogen and phosphorous obtained during 14 months working at different SCLRs and nutrient dosages. The representation of the microorganism group distribution in the biofilm and in the bulk liquid allow for verification of the presence of predator microorganisms in the second reactor under some operational conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Application of integrated ozone and granular activated carbon for decolorization and chemical oxygen demand reduction of vinasse from alcohol distilleries.

    Science.gov (United States)

    Hadavifar, Mojtaba; Younesi, Habibollah; Zinatizadeh, Ali Akbar; Mahdad, Faezeh; Li, Qin; Ghasemi, Zahra

    2016-04-01

    This study investigates the treatment of the distilleries vinasse using a hybrid process integrating ozone oxidation and granular activated carbons (GAC) in both batch and continuous operation mode. The batch-process studies have been carried out to optimize initial influent pH, GAC doses, the effect of the ozone (O3) and hydrogen peroxide (H2O2) concentrations on chemical oxygen demand (COD) and color removal of the distilleries vinasse. The continuous process was carried out on GAC and ozone treatment alone as well as the hybrid process comb both methods to investigate the synergism effectiveness of the two methods for distilleries vinasse COD reduction and color removal. In a continuous process, the Yan model described the experimental data better than the Thomas model. The efficiency of ozonation of the distilleries vinasse was more effective for color removal (74.4%) than COD removal (25%). O3/H2O2 process was not considerably more effective on COD and color removal. Moreover, O3/GAC process affected negatively on the removal efficiency by reducing COD and color from distilleries vinasse. The negative effect decreased by increasing pH value of the influent. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Pecan shell-based granular activated carbon for treatment of chemical oxygen demand (COD) in municipal wastewater.

    Science.gov (United States)

    Bansode, R R; Losso, J N; Marshall, W E; Rao, R M; Portier, R J

    2004-09-01

    The present investigation was undertaken to compare the adsorption efficiency of pecan shell-based granular activated carbon with the adsorption efficiency of the commercial carbon Filtrasorb 200 with respect to uptake of the organic components responsible for the chemical oxygen demand (COD) of municipal wastewater. Adsorption efficiencies for these two sets of carbons (experimental and commercial) were analyzed by the Freundlich adsorption model. The results indicate that steam-activated and acid-activated pecan shell-based carbons had higher adsorption for organic matter measured as COD, than carbon dioxide-activated pecan shell-based carbon or Filtrasorb 200 at all the carbon dosages used during the experiment. The higher adsorption may be related to surface area as the two carbons with the highest surface area also had the highest organic matter adsorption. These results show that granular activated carbons made from agricultural waste (pecan shells) can be used with greater effectiveness for organic matter removal from municipal wastewater than a coal-based commercial carbon. Copyright 2004 Elsevier Ltd.

  11. Miniaturized and green method for determination of chemical oxygen demand using UV-induced oxidation with hydrogen peroxide and single drop microextraction

    International Nuclear Information System (INIS)

    Akhoundzadeh, Jeyran; Chamsaz, Mahmoud; Costas, Marta; Lavilla, Isela; Bendicho, Carlos

    2013-01-01

    We report on a green method for the determination of low levels of chemical oxygen demand. It is based on the combination of (a) UV-induced oxidation with hydrogen peroxide, (b) headspace single-drop microextraction with in-drop precipitation, and (c) micro-turbidimetry. The generation of CO 2 after photolytic oxidation followed by its sequestration onto a microdrop of barium hydroxide gives rise to a precipitate of barium carbonate which is quantified by turbidimetry. UV-light induced oxidation was studied in the absence and presence of H 2 O 2 , ultrasound, and ferrous ion. Determinations of chemical oxygen demand were performed using potassium hydrogen phthalate as a model compound. The optimized method gives a calibration curve that is linear between 3.4 and 20 mg L −1 oxygen. The detection limit was 1.2 mg L −1 of oxygen, and the repeatability (as relative standard deviation) was around 5 %. The method was successfully applied to the determination of chemical oxygen demand in different natural waters and a synthetic wastewater. (author)

  12. BAYESIAN PARAMETER ESTIMATION IN A MIXED-ORDER MODEL OF BOD DECAY. (U915590)

    Science.gov (United States)

    We describe a generalized version of the BOD decay model in which the reaction is allowed to assume an order other than one. This is accomplished by making the exponent on BOD concentration a free parameter to be determined by the data. This "mixed-order" model may be ...

  13. The Effect of H2O2 Interference in Chemical Oxygen Demand Removal During Advanced Oxidation Processes

    Directory of Open Access Journals (Sweden)

    Afsane Chavoshani

    2016-07-01

    Full Text Available Hydrogen peroxide (H2O2 is one of the most oxidants in AOPs. By H2O2 dissociation, hydroxyl radical with a standard oxidation potential of 2.7 is produced. It is reported H2O¬ residual in AOPs has been led to interference in chemical oxygen demand (COD test and it is able to hinder biological treatment of waste water. Because of high mixed organic load of solid waste leachate, this study investigated effect of H2O2 interference in COD removal from solid waste leachate. In this study effect of parameters such as pH (3,5,7,12, H2O2 dose (0.01, 0.02, 0.03, 0.04 mol l-1, and time reaction(10,20,30,40,50,60 min evaluated on H2O2 interference in COD removal from solid waste leachate. Optimum pH and concentration were 3 and 0.02 moll-1 respectively. With increasing reaction time, COD removal was increased. The false COD obtained between 0.49mg per 1mg of H2O2. The average of COD removal by H2O2 for 60 min was 6.57%. Also reaction rate of this process was 0.0029 min-1. The presence of H2O2 leads to overestimation of COD values after reaction time because it consumes the oxidation agent. The extent of H2O2 interference in COD analysis was proportional to the remaining H2O2 concentration at the moment of sampling.

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

    Science.gov (United States)

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

    2017-04-01

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

  15. Ability of the aquatic fern Azolla to remove chemical oxygen demand and polyphenols from olive mill wastewater

    Directory of Open Access Journals (Sweden)

    Sacchi, Angelo

    2007-03-01

    Full Text Available We investigated the biofiltration ability of the aquatic fern Azolla to remove polyphenols and chemical oxygen demand (COD from olive mill wastewater (OMWw collected from the traditional (TS and continuous (CS extraction systems. Azolla biomass was packed into five sequential Imhoff cones and five sequential columns. In both experiments, the filtrates collected from the 5th biofilter showed a decrease in polyphenol contents: from 7650 mg l–1 to 3610 mg l–1 in TS OMWw and from 3852 mg l–1 to 1351 mg l–1 in CS OMWw. The COD contents decreased from 110200 mg L–1 to 52400 mg L–1 in TS OMWw and from 41600 mg L–1 to 2300 mg L–1 in CS OMWw. A 5:1 OMWw to Azolla-fresh-weight ratio was optimal for both polyphenol and COD removal. The biofiltration ability of alfalfa was compared with that of Azolla, but the treatment with alfalfa did not result in the reduction of COD or polyphenols.La eficacia del helecho de agua azolla para eliminar polifenoles y reducir la demanda química de oxígeno (DQO de los alpechines obtenidos en el proceso de obtención tradicional y continuo del aceite de oliva, fue investigado mediante ensayos de filtración. Cinco conos secuenciales de Imhoff y cinco columnas secuenciales se rellenaron de biomasa de Azolla. En ambos experimentos, el filtrado procedente de la quinta extracción mostró una disminución en el contenido de polifenoles de 7650 mg L–1 a 3610 mg L–1en el alpechín obtenido mediante el sistema tradicional y de 3852 mg L–1 a 1351 mg L–1en el alpechín del sistema continuo. La demanda química de oxígeno del alpechín del sistema tradicional disminuyó de 110200 mg L–1 a 52400 mg L–1 en y de 41600 mg L–1a 2300 mg L–1en el procedente del sistema continuo. Una proporción en peso 5:1 de alpechín: Azolla fue la óptima tanto para la reducción de los polifenoles como para la de la DQO. La eficiencia del tratamiento biológico con alfalfa se comparó con la obtenida con Azolla. Los

  16. Determination of chemical oxygen demand (COD) using an alternative wet chemical method free of mercury and dichromate.

    Science.gov (United States)

    Kolb, Marit; Bahadir, Müfit; Teichgräber, Burkhard

    2017-10-01

    Worldwide, the standard methods for the determination of the important wastewater parameter chemical oxygen demand (COD) are still based on the use of the hazardous chemicals, mercury sulfate and chromium(VI). However, due to their properties they are meanwhile classified as "priority pollutants" and shall be phased out or banned in the frame of REACH (current European Chemical Law: Registration, Evaluation, Authorization and restriction of Chemicals) by the European Union. Hence, a new wet-chemical method free of mercury and chromium(VI) was developed. Manganese(III) was used as oxidant and silver nitrate for the removal of chloride ions. The quantification was performed by back titration of manganese(III) with iron(II) as done in the standard method. In order to minimize losses of organic substances during the precipitation of silver chloride, suspended and colloid organic matter had to be separated by precipitation of aluminum hydroxide in a first step. In these cases, two fractions, one of the suspended and colloid matters and a second of the dissolved organic substances, are prepared and oxidized separately. The method was tested with potassium hydrogen phthalate (KHP) as conventional COD reference substance and different types of wastewater samples. The oxidation of KHP was reproducible in a COD range of 20-500 mg/L with a mean recovery rate of 88.7% in comparison to the standard COD method (DIN 38409-41). Also in presence of 1000 mg/L chloride a recovery rate of 84.1% was reached. For a series of industrial and municipal wastewater samples a high correlation (R 2  = 0.9935) to the standard method with a mean recovery rate of 78.1% (±5.2%) was determined. Even though the results of the new method are not 100% of the standard method, its high correlation to the standard method and reproducibility offers an environmentally benign alternative method with no need to purchase new laboratory equipment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Model development for prediction and mitigation of dissolved oxygen sags in the Athabasca River, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Nancy, E-mail: nancy@ualberta.ca [Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada T6G 2W2 (Canada); McEachern, Preston [Tervita Corporation, AB (Canada); Yu, Tong; Zhu, David Z. [Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada T6G 2W2 (Canada)

    2013-01-15

    Northern rivers exposed to high biochemical oxygen demand (BOD) loads are prone to dissolved oxygen (DO) sags in winter due to re-aeration occurring within limited open water leads. Additionally, photosynthesis is reduced by decreased daylight hours, inability of solar radiation to pass through ice, and slower algal growth in winter. The low volumetric flow decreases point-source dilution while their travel time increases. The Athabasca River in Alberta, Canada, has experienced these sags which may affect the aquatic ecosystem. A water quality model for an 800 km reach of this river was customized, calibrated, and validated specifically for DO and the factors that determine its concentration. After validation, the model was used to assess the assimilative capacity of the river and mitigation measures that could be deployed. The model reproduced the surface elevation and water temperature for the seven years simulated with mean absolute errors of < 15 cm and < 0.9 °C respectively. The ice cover was adequately predicted for all seven winters, and the simulation of nutrients and phytoplankton primary productivity were satisfactory. The DO concentration was very sensitive to the sediment oxygen demand (SOD), which represented about 50% of the DO sink in winter. The DO calibration was improved by implementing an annual SOD based on the BOD load. The model was used to estimate the capacity of the river to assimilate BOD loads in order to maintain a DO concentration of 7 mg/L, which represents the chronic provincial guideline plus a buffer of 0.5 mg/L. The results revealed the maximum assimilative BOD load of 8.9 ton/day at average flow conditions, which is lower than the maximum permitted load. In addition, the model predicted a minimum assimilative flow of about 52 m{sup 3}/s at average BOD load. Climate change scenarios could increase the frequency of this low flow. A three-level warning-system is proposed to manage the BOD load proactively at different river

  18. Effect of ozonation on microbial fish pathogens, ammonia, nitrate, nitrite, and bod in simulated reuse hatchery water

    Energy Technology Data Exchange (ETDEWEB)

    Colberg, P.J.; Lingg, A.J.

    1978-10-01

    The effectiveness of ozone for eliminating fish pathogens and reducing nitrite, ammonia, and BOD associated with reuse hatchery systems was evaluated. Comparative survival rates of four bacterial fish pathogens and a bacterium-protozoan population during batch and continuous flow ozonation indicated a specific microbial ozone demand during batch treatment and 99% mortality of pathogens during continuous flow treatment. Oxidation of carbon and nitrite by ozone was rapid at low ozone concentrations; carbon and ammonia oxidation rates were pH dependent. The oxidation capacity of ozone in water was greatest at elevated pH even though lower ozone concentrations were used. Ozone treatment appears to be successful for disinfecting hatchery makeup water for recycling. However, the economics of such treatment are yet to be determined. (10 graphs, 28 references, 1 table)

  19. Quality improvement in determination of chemical oxygen demand in samples considered difficult to analyze, through participation in proficiency-testing schemes

    DEFF Research Database (Denmark)

    Raposo, Francisco; Fernández-Cegrí, V.; De la Rubia, M.A.

    2010-01-01

    Chemical oxygen demand (COD) is a critical analytical parameter in waste and wastewater treatment, more specifically in anaerobic digestion, although little is known about the quality of measuring COD of anaerobic digestion samples. Proficiency testing (PT) is a powerful tool that can be used...... to test the performance achievable in the participants laboratories, so we carried out a second PT of COD determination in samples considered ‘‘difficult’’ to analyze (i.e. solid samples and liquid samples with high concentrations of suspended solids). The results obtained (based on acceptable z...

  20. Perbedaan Efektivitas Zeolit Dan Manganese Greensand Untuk Menurunkan Kadar Fosfat Dan Chemical Oxygen Demand Limbah Cair “Laundry Zone” Di Tembalang

    OpenAIRE

    Lavina, Dahona Lenthe; Sulistyani, Sulistyani; Rahadjo, Mursid

    2016-01-01

    Laundry business is a business in clothes washing services. Preliminary test results show that the levels of phosphate and COD laundry liquid wastes is 12,36 mg/l and 5.920 mg/l. These levels exceeded the water quality standard of waste that phosphate concentration of 2 mg/l and COD concentration of 100 mg/l. This research aimed to determine the difference effectiveness of zeolite and manganese greensand to decrease phosphate and chemical oxygen demand on waste "laundry zone" in Tembalang. T...

  1. The supply and demand for pollution control: Evidence from wastewater treatment

    Science.gov (United States)

    McConnell, V.D.; Schwarz, G.E.

    1992-01-01

    This paper analyzes the determination of pollution control from wastewater treatment plants as an economic decision facing local or regional regulators. Pollution control is measured by plant design effluent concentration levels and is fully endogenous in a supply- and-demand model of treatment choice. On the supply side, plant costs are a function of the design treatment level of the plant, and on the demand side, treatment level is a function of both the costs of control and the regional or regulatory preferences for control. We find evidence that the economic model of effluent choice by local regulators has a good deal of explanatory power. We find evidence that wastewater treatment plant removal of biological oxygen demand (BOD) is sensitive to many local factors including the size of the treatment plant, the flow rate of the receiving water, the population density of the surrounding area, regional growth, state sensitivity to environmental issues, state income, and the extent to which the damages from pollution fall on other states. We find strong evidence that regulators are sensitive to capital costs in determining the design level of BOD effluent reduction at a plant. Thus, proposed reductions in federal subsidies for wastewater treatment plant construction are likely to have significant adverse effects on water quality. ?? 1992.

  2. PEMANFAATAN SPUIT BEKAS SEBAGAI MEDIA BIOFILTRASI DALAM MENURUNKAN KADAR BOD DAN COD AIR LIMBAH LAUNDRY

    Directory of Open Access Journals (Sweden)

    Susilawati Susilawati

    2016-07-01

    Full Text Available Abstract: Utilization Spuit Used As Media biofilters on Reducing levels of BOD and COD Wastewater Laundry. The aim of this study was to test the ability of the media syringe biofiltration method used in lowering levels of BOD and COD in waste water laundry Hospital Dr. Soedarso Pontianak. This research is a quasi-experimental research design with one group pretest-posttest. Laboratory results mean BOD levels before processing is 103.63 mg/L and the average after processing into 46.41 mg/ L, with a value of 55.21 % effectiveness. While the average COD level before processing is 413.70 mg / L and the average after processing into a 195.88 mg/L with a value of 45.92% effectiveness. Expected to other researchers to control the pH and blowers before treatment and during treatment, as it will affect the final result. Abstrak : Pemanfaatan Spuit Bekas Sebagai Media Biofiltrasi Dalam Menurunkan Kadar BOD dan COD Air Limbah Laundry. Tujuan dari penelitian ini untuk menguji kemampuan metode biofiltrasi dengan media spuit bekas pakai dalam menurunkan kadar BOD dan COD pada air limbah laundry RSUD Dr. Soedarso Pontianak. Penelitian ini merupakan penelitian eksperimen semu dengan rancangan penelitian one group pre test post test. Hasil laboratorium rata-rata kadar BOD sebelum pengolahan yaitu 103.63 mg/L dan rata-rata setelah pengolahan menjadi 46.41 mg/L, dengan nilai efektivitas 55,21 %. Sedangkan rata-rata kadar COD sebelum pengolahan yaitu 413.70 mg/L dan rata-rata setelah pengolahan menjadi 195.88 mg/L dengan nilai efektivitas 45,92 %. Diharapkan kepada peneliti lain untuk mengontrol pH dan blower sebelum perlakuan dan pada saat perlakuan, jika melakukan penelitian sejenis karena akan mempengaruhi hasil akhir.

  3. Construction of Microbial-based Biosensor to Measure BOD of Industrial Wastewaters

    Directory of Open Access Journals (Sweden)

    Behnam Mahdavi

    2014-04-01

    Full Text Available In this study a cell-based biosensor for measurement of BOD was designed and developed. Activated sludge collected from wastewater treatment plant of Shahinshahr was used as biological receptor and a Clark cell was used as transducer. According to the results obtained from the sensor calibration, a linear relationship between the current changes and glucose-glutamic acid (GAA standard concentrations up to 50 mg/L was observed. The BOD values of different industrial wastewaters, inlet and outlet of treatment plant of Ardineh Company (Isfahan, and also  inlet and outlet of domestic wastewater treatment plant of Shahinshahr, and outlet of treatment plant of Pegah Company (Isfahan were measured using this biosensor. Comparison of the results of this biosensor and the results of the standard BOD test (BOD5 showed that the mean percentage error measured by the sensor was +29.6%. The results concerning the stability of the designed biosensor showed a stability time of 3 days for the response of biosensor.

  4. Reliability of BOD POD Measurements Remains High After a Short-Duration Low-Carbohydrate Diet.

    Science.gov (United States)

    Greer, Beau Kjerulf; Edsall, Kathleen M; Greer, Anna E

    2016-04-01

    The purpose of the current study was to determine whether expected changes in body weight via a 3-day low-carbohydrate (LC) diet will disrupt the reliability of air displacement plethysmography measurements via BOD POD. Twenty-four subjects recorded their typical diets for 3 days before BOD POD and 7-site skinfold analyses. Subjects were matched for lean body mass and divided into low-CHO (LC) and control (CON) groups. The LC group was given instruction intended to prevent more than 50 grams/day of carbohydrate consumption for 3 consecutive days, and the CON group replicated their previously recorded diet. Body composition measurements were repeated after dietary intervention. Test-retest reliability measures were significant (p fat percentage in both the LC and the CON groups (rs = .993 and .965, respectively). Likewise, skinfold analysis for body fat percentage reliability was high in both groups (rs = .996 and .997, respectively). There were significant differences between 1st and 2nd BOD POD measurements for body mass (72.9 ± 13.3 vs. 72.1 ± 13.0 kg [M ± SD]) and body volume (69.0 ± 12.7-68.1 ± 12.2 L) in the LC group (p .05) in BOD POD-determined body fat percentage, lean body mass, or fat mass between the 1st and 2nd trial in either group. Body composition measures via BOD POD and 7-site skinfolds remain reliable after 3 days of an LC diet despite significant decreases in body mass.

  5. Chemical oxygen demand removal efficiency and limited factors study of aminosilicone polymers in a water emulsion by iron-carbon micro-electrolysis.

    Science.gov (United States)

    Yang, Shangyuan; Liang, Zhiwei; Yu, Huadong; Wang, Yunlong; Chen, Yingxu

    2014-02-01

    Micro-electrolysis was applied in the present study to investigate the effect of pH, iron-carbon mass ratio, contact time, and treatment batch on the removal efficiency of chemical oxygen demand (COD) within an aminosilicone emulsion. The results exhibited that the removal efficiency of COD decreased linearly with the batch increase, and this tendency was consistent under the various conditions. The adsorption of activated carbons contributes a large portion to the elimination of COD within the aminosilicone emulsion. The oxidation action of iron-carbon micro-electrolysis was proven and the aminosilicone emulsion's COD removal contribution was approximately 16%. Aminosilicone polymers were adsorbed on the surface of activated carbons and iron chips, which contributes to the decline of COD removal efficiency and limits the contribution of oxidation action.

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-07-01

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

  8. A new route of bioaugmentation by allochthonous and autochthonous through biofilm bacteria for soluble chemical oxygen demand removal of old leachate.

    Science.gov (United States)

    Alijani Ardeshir, Rashid; Rastgar, Sara; Peyravi, Majid; Jahanshahi, Mohsen; Shokuhi Rad, Ali

    2017-10-01

    Landfill leachate contains environmental pollutants that are generally resistant to biodegradation. In this study, indigenous and exogenous bacteria in leachate were acclimated in both biofilm and suspension forms to increase the removal of soluble chemical oxygen demand (SCOD). The bacteria from the leachate and sewage were acclimated to gradually increasing leachate concentration prepared using a reverse osmosis membrane over 28 days. The SCOD removal was measured aerobically or nominally anaerobically. Biofilms were prepared using different carrier media (glass, rubber, and plastic). The maximum SCOD removal in suspensions was 32% (anaerobic) and in biofilms was 39% (aerobic). In the suspension form, SCOD removal using acclimated bacteria from leachate and sewage anaerobically increased in comparison with the control (P technology using biofilms and acclimations can be an effective, inexpensive, and simple way to decrease SCOD in old landfill leachate.

  9. Dual effect of fetal bovine serum on early development depends on stage-specific reactive oxygen species demands in pigs.

    Directory of Open Access Journals (Sweden)

    Seong-Eun Mun

    Full Text Available Despite the application of numerous supplements to improve in vitro culture (IVC conditions of mammalian cells, studies regarding the effect of fetal bovine serum (FBS on mammalian early embryogenesis, particularly in relation to redox homeostasis, are lacking. Herein, we demonstrated that early development of in vitro-produced (IVP porcine embryos highly depends on the combination of FBS supplementation timing and embryonic reactive oxygen species (ROS requirements. Interestingly, FBS significantly reduced intracellular ROS levels in parthenogenetically activated (PA embryos regardless of the developmental stage. However, the beneficial effect of FBS on early embryogenesis was found only during the late phase (IVC 4-6 days treatment group. In particular, developmental competence parameters, such as blastocyst formation rate, cellular survival, total cell number and trophectoderm proportion, were markedly increased by FBS supplementation during the late IVC phase. In addition, treatment with FBS elevated antioxidant transcript levels during the late IVC phase. In contrast, supplementation with FBS during the entire period (1-6 days or during the early IVC phase (1-2 days greatly impaired the developmental parameters. Consistent with the results from PA embryos, the developmental competence of in vitro fertilization (IVF or somatic cell nuclear transfer (SCNT embryos were markedly improved by treatment with FBS during the late IVC phase. Moreover, the embryonic stage-specific effects of FBS were reversed by the addition of an oxidant and were mimicked by treatment with an antioxidant. These findings may increase our understanding of redox-dependent early embryogenesis and contribute to the large-scale production of high-quality IVP embryos.

  10. Influence of myocardial oxygen demand on the coronary vascular response to arterial blood gas changes in humans.

    Science.gov (United States)

    Vermeulen, Tyler Dennis; Boulet, Lindsey M; Stembridge, Mike; Williams, Alexandra Mackenzie; Anholm, James D; Subedi, Prajan; Gasho, Chris; Ainslie, Philip N; Feigl, Eric O; Foster, Glen Edward

    2018-03-30

    It remains unclear if the human coronary vasculature is inherently sensitive to changes in arterial PO 2 and PCO 2 or if coronary vascular responses are the result of concomitant increases in myocardial O 2 consumption/demand (MVO 2 ). We hypothesized that the coronary vascular response to PO 2 and PCO 2 would be attenuated in healthy men when MVO 2 was attenuated with β 1 -adrenergic receptor blockade. Healthy men (n=11; age: 25 {plus minus} 1 years) received intravenous esmolol (β 1 -adrenergic receptor antagonist) or volume-matched saline in a double-blind, randomized, crossover study, and were exposed to poikilocapnic hypoxia, isocapnic hypoxia, and hypercapnic hypoxia. Measurements made at baseline and following 5-min of steady state at each gas manipulation included left anterior descending coronary blood velocity (LAD V ; Doppler echocardiography), heart rate and arterial blood pressure. LAD V values at the end of each hypoxic condition were compared between esmolol and placebo. Rate pressure product (RPP) and left-ventricular mechanical energy (ME LV ) were calculated as indices of MVO 2 . All gas manipulations augmented RPP, ME LV , and LAD V but only RPP and ME LV were attenuated (4-18%) following β 1 -adrenergic receptor blockade (P<0.05). Despite attenuated RPP and MELV responses, β 1 -adrenergic receptor blockade did not attenuate the mean LADV vasodilatory response when compared to placebo during poikilocapnic hypoxia (29.4{plus minus}2.2 vs. 27.3{plus minus}1.6 cm/s) and isocapnic hypoxia (29.5{plus minus}1.5 vs. 30.3{plus minus}2.2 cm/s). Hypercapnic hypoxia elicited a feed-forward coronary dilation that was blocked by β 1 -adrenergic receptor blockade. These results indicate a direct influence of arterial PO 2 on coronary vascular regulation that is independent of MVO 2 .

  11. Reduction Colour and BOD of Textile Waste by Carbon-TiO2

    International Nuclear Information System (INIS)

    Budi Setiawan; Rosyidin; Nurimaniwathy

    2007-01-01

    The Granule Forming of Carbon adsorbent has been done with 5, 10, 15% of TiO 2 using the variation of adhesive materials on 110, 130, and 150 °C with diameter of 0.5 and 1 cm. The adsorbent materials was used to media of color levels absorption and BOD level on textile waste product by using stirring methods. The variation of stirring 20, 40 and 60 minutes. The result showed that the best materials condition and process were fox glue on 110 °C, stirring time at 60 minutes at 15% TiO 2 , which potent to adsorb colours level 29.608% and BOD level 66.157%. (author)

  12. Achieving low effluent NO3-N and TN concentrations in low influent chemical oxygen demand (COD) to total Kjeldahl nitrogen (TKN) ratio without using external carbon source

    Science.gov (United States)

    Cao, Jiashun; Oleyiblo, Oloche James; Xue, Zhaoxia; Otache, Y. Martins; Feng, Qian

    2015-07-01

    Two mathematical models were used to optimize the performance of a full-scale biological nutrient removal (BNR) activated treatment plant, a plug-flow bioreactors operated in a 3-stage phoredox process configuration, anaerobic anoxic oxic (A2/O). The ASM2d implemented on the platform of WEST2011 software and the BioWin activated sludge/anaerobic digestion (AS/AD) models were used in this study with the aim of consistently achieving the designed effluent criteria at a low operational cost. Four ASM2d parameters (the reduction factor for denitrification , the maximum growth rate of heterotrophs (µH), the rate constant for stored polyphosphates in PAOs ( q pp), and the hydrolysis rate constant ( k h)) were adjusted. Whereas three BioWin parameters (aerobic decay rate ( b H), heterotrophic dissolved oxygen (DO) half saturation ( K OA), and Y P/acetic) were adjusted. Calibration of the two models was successful; both models have average relative deviations (ARD) less than 10% for all the output variables. Low effluent concentrations of nitrate nitrogen (N-NO3), total nitrogen (TN), and total phosphorus (TP) were achieved in a full-scale BNR treatment plant having low influent chemical oxygen demand (COD) to total Kjeldahl nitrogen (TKN) ratio (COD/TKN). The effluent total nitrogen and nitrate nitrogen concentrations were improved by 50% and energy consumption was reduced by approximately 25%, which was accomplished by converting the two-pass aerobic compartment of the plug-flow bioreactor to anoxic reactors and being operated in an alternating mode. Findings in this work are helpful in improving the operation of wastewater treatment plant while eliminating the cost of external carbon source and reducing energy consumption.

  13. Accuracy of different sensors for the estimation of pollutant concentrations (total suspended solids, total and dissolved chemical oxygen demand) in wastewater and stormwater.

    Science.gov (United States)

    Lepot, Mathieu; Aubin, Jean-Baptiste; Bertrand-Krajewski, Jean-Luc

    2013-01-01

    Many field investigations have used continuous sensors (turbidimeters and/or ultraviolet (UV)-visible spectrophotometers) to estimate with a short time step pollutant concentrations in sewer systems. Few, if any, publications compare the performance of various sensors for the same set of samples. Different surrogate sensors (turbidity sensors, UV-visible spectrophotometer, pH meter, conductivity meter and microwave sensor) were tested to link concentrations of total suspended solids (TSS), total and dissolved chemical oxygen demand (COD), and sensors' outputs. In the combined sewer at the inlet of a wastewater treatment plant, 94 samples were collected during dry weather, 44 samples were collected during wet weather, and 165 samples were collected under both dry and wet weather conditions. From these samples, triplicate standard laboratory analyses were performed and corresponding sensors outputs were recorded. Two outlier detection methods were developed, based, respectively, on the Mahalanobis and Euclidean distances. Several hundred regression models were tested, and the best ones (according to the root mean square error criterion) are presented in order of decreasing performance. No sensor appears as the best one for all three investigated pollutants.

  14. Enhanced removal of chemical oxygen demand, nitrogen and phosphorus using the ameliorative anoxic/anaerobic/oxic process and micro-electrolysis.

    Science.gov (United States)

    Bao, K Q; Gao, J Q; Wang, Z B; Zhang, R Q; Zhang, Z Y; Sugiura, N

    2012-01-01

    Synthetic wastewater was treated using a novel system integrating the reversed anoxic/anaerobic/oxic (RAAO) process, a micro-electrolysis (ME) bed and complex biological media. The system showed superior chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) removal rates. Performance of the system was optimised by considering the influences of three major controlling factors, namely, hydraulic retention time (HRT), organic loading rate (OLR) and mixed liquor recirculation (MLR). TP removal efficiencies were 69, 87, 87 and 83% under the HRTs of 4, 8, 12 and 16 h. In contrast, HRT had negligible effects on the COD and TN removal efficiencies. COD, TN and TP removal efficiencies from synthetic wastewater were 95, 63 and 87%, respectively, at an OLR of 1.9 g/(L·d). The concentrations of COD, TN and TP in the effluent were less than 50, 15 and 1 mg/L, respectively, at the controlled MLR range of 75-100%. In this system, organics, TN and TP were primarily removed from anoxic tank regardless of the operational conditions.

  15. Coupling of anodic oxidation and adsorption by granular activated carbon for chemical oxygen demand removal from 4,4'-diaminostilbene-2,2'-disulfonic acid wastewater.

    Science.gov (United States)

    Wang, Lizhang; Zhao, Yuemin

    2010-01-01

    Experiments were performed to reduce chemical oxygen demand (COD) from 4,4'-diaminostilbene-2,2'-disulfonic (DSD) acid manufacturing wastewater using electrochemical oxidation coupled with adsorption by granular activated carbon. The COD removal is affected by the residence time and applied voltage. When the residence time is increased, lower value of COD effluent could be obtained, however, the average current efficiency (ACE) decreased rapidly, and so does the applied voltage. In addition, aeration could effectively enhance COD removal efficiency and protect anodes from corrosion. Furthermore, the acidic condition is beneficial to the rapid decrease of COD and the values of pH effluent are independent of the initial solution pH. The optimization conditions obtained from these experiments are applied voltage of 4.8 V, residence time of 180 min and air-liquid ratio of 4.2 with the COD effluent of about 690 mg L⁻¹. In these cases, the ACE and energy consumption are 388% and 4.144 kW h kg⁻¹ COD, respectively. These perfect results from the experiments illustrate that the combined process is a considerable alternative for the treatment of industrial wastewater containing high concentration of organic pollutants and salinity.

  16. Quantitative relations between chemical oxygen demand concentration and its influence factors in the sluice-controlled river reaches of Shaying River, China.

    Science.gov (United States)

    Dou, Ming; Li, Guiqiu; Li, Congying

    2015-01-01

    Recent research on the effects of dam and sluice construction on the water environment has attracted extensive attention from academia and governments alike. Because the operation of sluices greatly alters environmental factors such as water flow and sediment load, the water quality in sluice-controlled river reaches (SCRRs) undergoes complex changes compared with those in normal reaches. This work used river reaches near the Huaidian Sluice in Shaying River of China as a case study to analyse the effects of sluice operation on water quality evolution in SCRRs. The most influential factors affecting the rate of change in chemical oxygen demand (COD) concentration in SCRRs were identified through water quality monitoring experiments performed under various modes of sluice operation and by applying a statistical method 'partial correlation analysis'. Then, a hydrodynamic model incorporating sluice operation and a water quality transport and transform model incorporating the release of endogenous loads were developed. Using these two models, the processes of temporal and spatial change of COD concentrations in the SCRRs were simulated under various scenarios designed to represent the dominant factors of influence. Finally, the simulation results were used to develop empirical relationships between the rate of change in COD concentrations and the dominant factors of influence. The results reveal that three factors, i.e., water inflow concentration, gate opening size, and gate opening number, are the dominant factors of influence, and there are logarithmic relationships between the rate of change in COD concentration in the SCRRs and these factors.

  17. Effects of acute and 2-hour postphysical activity on the estimation of body fat made by the bod pod.

    Science.gov (United States)

    Harrop, Bradley J; Woodruff, Sarah J

    2015-06-01

    The Bod Pod has been found to be reliable/valid against several criterion methods, including hydrostatic weighing and dual-energy x-ray absorptiometry, and under different conditions, such as clothing, dehydrated states, and body temperature changes. However, questions remain regarding the effects of an acute bout of exercise. Therefore, the purpose was to determine the effects of an acute bout of exercise on the estimations made by the Bod Pod. Participants (15 men and 22 women) were of age 18-27 years and were currently exercising. Baseline Bod Pod measures were completed followed by a 30-minute cycling trial at 75% of maximum heart rate. Bod Pod measures were taken immediately after exercise and 2 hours after exercise. Differences between men and women were found at baseline between height (p temperature (p temperature (p estimate of %BF, and continues to affect the prediction 2 hours after exercise in women.

  18. KEMAMPUAN SISTEM SARINGAN PASIR-TANAMAN MENURUNKAN NILAI BOD DAN COD AIR TERCEMAR LIMBAH PENCELUPAN

    Directory of Open Access Journals (Sweden)

    I W. Budiarsa Suyasa

    2012-11-01

    Full Text Available Colored of clothes has developed as concentrated in Denpasar area. The process has a negativeeffect because of waste, the resulting organic toxicants and heavy metal into aquatic system. The effect ofthe pollution including the river, well water and organism that live there. The research of bioremedialeffectiveness of herb-sand treatment system on laboratory simulation were studied in Denpasar, from June2004 to September 2004.For laboratory simulation, the plants were cultured in 25 cm sand bed, in between 5 cm palmfiber ofwhich were in between 10 cm pumicestone for the top and 5 cm gravel for the bottom with surface area of 25x 50 cm2.The result of treatment system showed that effective for decrease biological oxygen demandcompared to those of chemical oxygen demand parameters. The treatment system reduced significantly BODlevel respectively to 13,15 for 3 days, 11,19 for 10 days and 5,79 for 20 days with 85,55 – 93,63 effectively.While COD level respectively to 76,68 for 3 days, 61,38 for 10 days and 58,57 for 20 days with 42,78 – 56,50effectively. Time of treatment for 3, 10 and 20 days showed a little increase of pH from 6,87 to 7,00.

  19. [Pollution load and the first flush effect of BOD5 and COD in urban runoff of Wenzhou City].

    Science.gov (United States)

    Wang, Jun; Bi, Chun-juan; Chen, Zhen-lou; Zhou, Dong

    2013-05-01

    Four typical rainfalls were monitored in two different research areas of Wenzhou Municipality. Concentrations of BOD5 and COD in six different urban runoffs were measured. In addition the event mean concentration (EMC), M (V) curve and BOD5/COD of pollutant were calculated. The results showed that concentrations of BOD5 and COD in different urban runoffs of Wenzhou ranged from ND to 69.21 mg x L(-1) and ND to 636 mg x L(-1). Concentrations of BOD5 and COD in different urban runoffs were decreasing over time, so it is greatly significant to manage the initial runoff for reducing organic pollution. Judged by EMC of BOD5 and COD in these five rainfalls, concentrations of pollutant in some urban runoffs were out of the integrated wastewater discharge standard. If these runoffs flowed into river, it would cause environmental pressure to the next level receiving water bodies. According to the M (V) curve, the first flush effect of COD in most urban runoffs was common; while the first flush effect of BOD5 was same as that of COD. The result also showed that organic pollution was serious at the beginning of runoff. The underlying surface type could affect the concentration of BOD5 and COD in urban runoff. While the results of BOD5/COD also suggested that biodegradation was considered as one of the effective ways to decrease the pollution load of organics in urban runoff, and the best management plans (BMPs) should be selected for various urban runoff types for the treatment of organic pollution.

  20. Comparison of Poly Aluminum Chloride and Chlorinated Cuprous for Chemical Oxygen Demand and Color Removal from Kashan Textile Industries Company Wastewater

    Directory of Open Access Journals (Sweden)

    Hoseindoost Gh.1 MSPH,

    2016-08-01

    Full Text Available Aims Textile wastewaters are the most important health and environmental problems in Kashan. This research was aimed to compare the poly aluminum chloride and chlorinated cuprous efficiency for removal of Chemical Oxygen Demand (COD and color from Kashan Textile Industries Company wastewater. Materials & Methods This experimental bench scale study in a batch system was conducted on 20 composed wastewater samples collected from Kashan Textile Industries Company raw wastewater. During 5 months, in the beginning of every week a day was selected randomly and in the day a composed sample was taken and studied. PAC at the doses of 10, 20, 30, 40 and 50mg.l-1 and chlorinated cuprous at the doses of 100, 200, 300, 400 and 500mg.l-1 were applied. The optimum pH also optimum concentration of PAC and chlorinated cuprous were determined using Jar test. The data was analyzed by SPSS 16 using descriptive statistics and Fisher Exact test. Findings The average concentration of COD in the raw textile wastewater was 2801.56±1398.29mg.l-1. The average COD concentration has been decreased to 1125.47±797.55mg.l-1. There was a significant difference between the effects of these two coagulants efficiency (p<0.05. The average COD removal efficiency for chlorinated cuprous and PAC was 58.52% and 72.56%, respectively. Also, the average color removal efficiency by chlorinated cuprous and PAC were 17.23 and 64.45%, respectively. Conclusion PAC is more efficient than chlorinated cuprous for both COD and color removal from KTIC wastewater.

  1. Biochemical oxygen demand and nutrient processing in a novel multi-stage raw municipal wastewater and acid mine drainage passive co-treatment system.

    Science.gov (United States)

    Strosnider, W H; Winfrey, B K; Nairn, R W

    2011-01-01

    A laboratory-scale, four-stage continuous flow reactor system was constructed to test the viability of high-strength acid mine drainage (AMD) and municipal wastewater (MWW) passive co-treatment. The synthetic AMD had pH 2.60 and 1860 mg/L acidity as CaCO(3) equivalent with 46, 0.25, 2, 290, 55, 1.2 and 390 mg/L of Al, As, Cd, Fe, Mn, Pb and Zn, respectively. The AMD was introduced to the system at a 1:2 ratio with raw MWW from the City of Norman, Oklahoma USA containing 265 ± 94 mg/L BOD(5), 11.5 ± 5.3 mg/L PO(4)(-3), and 20.8 ± 1.8 mg/L NH(4)(+)-N. During the 135 d experiment, PO(4)(-3) and NH(4)(+)-N were decreased to treatment is a viable ecological engineering approach for the developed and developing world that can be optimized and applied to improve water quality with minimal use of fossil fuels and refined materials. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. The influence of ozonated time on the degree of depreciation of BOD, COD, TSS and phosphate in hospital liquid waste

    International Nuclear Information System (INIS)

    Isyuniarto and Andrianto

    2009-01-01

    The influence of ozonated time towards degree depreciation of Bode, COD, TSS and phosphate in hospital liquid waste was done. This research aim study influence of lime adding and ozone using to reduce of BOD, COD, TSS and phosphate in hospital waste. Added of lime mean for total increase ion OH - , while parameter of ozonization time mean to complete organic compounds oxidation in waste and flock formation. From this research it was found that optimum lime addition was 1.1% (% weight) and ozonization time was 20 minutes. In this condition it was achieved degree of BOD = 18.88 mg/l; COD = 25.68 mg/l, TSS = 80 mg/l and phosphate = 1.52 mg/l. This condition fulfil quality standard decided, that has to BOD = 75 mg/l; COD = 100 mg/l, TSS = 100 mg/l and phosphate = 2.0 mg/l. (author)

  3. Treatment of swine wastewater in continuous activated sludge systems under different dissolved oxygen conditions: Reactor operation and evaluation using modelling.

    Science.gov (United States)

    Waki, Miyoko; Yasuda, Tomoko; Fukumoto, Yasuyuki; Béline, Fabrice; Magrí, Albert

    2018-02-01

    Swine wastewater was treated in two continuously aerated activated sludge (AS) systems at high (AS1: 1.7-2.6 mg/L) and low (AS2: 0.04-0.08 mg/L) dissolved oxygen (DO), and at three temperatures (10, 20, and 30 °C). Biochemical oxygen demand (BOD) removal was >94.8%. Meanwhile, total nitrogen (N) removal was significantly higher in AS2, at 64, 89, and 88%, than in AS1, at 12, 24, and 46%, for 10, 20, and 30 °C, respectively. The experimental data were considered in a simulation study using an AS model for BOD and N removal, which also included nitrite, free ammonia, free nitrous acid, and temperature. Simulations at high-DO showed that ammonium was partly oxidized into nitrate but not removed, whereas at low-DO ammonium was removed mainly through the nitrite shortcut in simultaneous nitrification-denitrification. This study demonstrates that treatment at low-DO is an effective method for removing N, and modelling a helpful tool for its optimization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Proceeding of US Army Corps of Engineers Workshop on Sediment Oxygen Demand Held in Providence, Rhode Island on 21-22 August 1990.

    Science.gov (United States)

    1992-06-01

    Eutrophication," Mar, Ecol, Prog., Ser. 3, pp 83-91. Pamatmat, M. M. 1971. "Oxygen Consumption by the Seabed. VI. Seasonal Cycle of Chemical Oxydation and...primarily ferrous iron) and easily degraded organic substances (primarily volatile fatty acids and alcohols ) within the sediment interstitial waters...compounds such as volatile fatty acids and alcohols , must be combined with oxygen through the process of microbial metabolism (see the paper by Jacobson

  5. Mineral dust emission from the Bodélé Depression, northern Chad, during BoDEx 2005

    Science.gov (United States)

    Todd, Martin C.; Washington, Richard; Martins, José Vanderlei; Dubovik, Oleg; Lizcano, Gil; M'bainayel, Samuel; Engelstaedter, Sebastian

    2007-03-01

    Mineral dust in the atmosphere is an important component of the climate system but is poorly quantified. The Bodélé Depression of northern Chad stands out as the world's greatest source region of mineral dust into the atmosphere. Frequent dust plumes are a distinguishing feature of the region's climate. There is a need for more detailed information on processes of dust emission/transport and dust optical properties to inform model simulations of this source. During the Bodélé Dust Experiment (BoDEx) in 2005, instrumentation was deployed to measure dust properties and boundary layer meteorology. Observations indicate that dust emission events are triggered when near-surface wind speeds exceed 10 ms-1, associated with synoptic-scale variability in the large-scale atmospheric circulation. Dust emission pulses in phase with the diurnal cycle of near-surface winds. Analysis of dust samples shows that the dust consists predominantly of fragments of diatomite sediment. The particle size distribution of this diatomite dust estimated from sun photometer data, using a modified Aeronet retrieval algorithm, indicates a dominant coarse mode (radius centered on 1-2 μm) similar to other Saharan dust observations. Single-scattering albedo values are high, broadly in line with other Saharan dust even though the diatomite composition of dust from the Bodélé is likely to be unusual. The radiative impact of high dust loadings results in a reduction in surface daytime maximum temperature of around 7°C in the Bodélé region. Using optical and physical properties of dust obtained in the field, we estimate the total dust flux emitted from the Bodélé to be 1.18 ± 0.45 Tg per day during a substantial dust event. We speculate that the Bodélé Depression (˜10,800 km2) may be responsible for between 6-18% of global dust emissions, although the uncertainty in both the Bodélé and global estimates remains high.

  6. Transport of North African dust from the Bodélé depression to the Amazon Basin: a case study

    Directory of Open Access Journals (Sweden)

    Y. Ben-Ami

    2010-08-01

    Full Text Available Through long-range transport of dust, the North-African desert supplies essential minerals to the Amazon rain forest. Since North African dust reaches South America mostly during the Northern Hemisphere winter, the dust sources active during winter are the main contributors to the forest. Given that the Bodélé depression area in southwestern Chad is the main winter dust source, a close link is expected between the Bodélé emission patterns and volumes and the mineral supply flux to the Amazon.

    Until now, the particular link between the Bodélé and the Amazon forest was based on sparse satellite measurements and modeling studies. In this study, we combine a detailed analysis of space-borne and ground data with reanalysis model data and surface measurements taken in the central Amazon during the Amazonian Aerosol Characterization Experiment (AMAZE-08 in order to explore the validity and the nature of the proposed link between the Bodélé depression and the Amazon forest.

    This case study follows the dust events of 11–16 and 18–27 February 2008, from the emission in the Bodélé over West Africa (most likely with contribution from other dust sources in the region the crossing of the Atlantic Ocean, to the observed effects above the Amazon canopy about 10 days after the emission. The dust was lifted by surface winds stronger than 14 m s−1, usually starting early in the morning. The lofted dust, mixed with biomass burning aerosols over Nigeria, was transported over the Atlantic Ocean, and arrived over the South American continent. The top of the aerosol layer reached above 3 km, and the bottom merged with the boundary layer. The arrival of the dusty air parcel over the Amazon forest increased the average concentration of aerosol crustal elements by an order of magnitude.

  7. Dissolved Organic In Natural and Polluted Waters: Methodology and Results of Running Control of Chemical Oxygen Demand (cod) For The Inland and Marine Aquatic System

    Science.gov (United States)

    Melentyev, K. V.; Worontsov, A. M.

    Current control of dissolved organic matter in natural and waste waters is the definition traditionally of chemical oxygen demand (COD) -- one of the basic parameters of quality of water. According to the International Standard (ISO 6060), it requires not less than one hour, while in many cases the operative information about amount of dissolved organic matter in aquatic environments have importance for prevention of an emergency. The standard method is applicable to waters with meaning of COD above 30 mg O2/l and, as the chloride ion prevents, it could be difficult for assessment of organic matter in sea water. Besides it is based on dichromate oxidation of the sum of organic substances in strong acid conditions at the presence of silver and mercury, that resulted in formation toxic pollutants. Till now attempts of automation of the COD definition in aquatic system were limited, basically, to duplication of the technology submitted the above standard (automatic COD analyzers "SERES Co."-- France, or "Tsvet Co." - Russia). The system of ozone-chemiluminescence automatic control of organic matter in water (CS COD) is offered and designed. Its based on the ozone oxidation of these substances in flowing water system and measurement arising from luminescent effects. CS COD works in real time. An instrument uses for reaction the atmospheric air, doesn't require fill of reagents and doesn't make new toxic pollutants. The system was tested in laboratory, and biochemical control of organic matter in water samples gathered from the river Neva and other polluted inland water areas and basins in St. Petersburg region was fulfilled (distilled water was used as "zero" media). The results of systematization of these measurements are presented. The new special ozone generator and flowing reactor for real-time running control of different waters in natural conditions were developed, and several series of large - scale field experiments onboard research ship were provided

  8. Post-ischaemic changes in the response time of oxygen consumption to demand in the isolated rat heart are mediated partly by calcium and glycolysis

    NARCIS (Netherlands)

    Zuurbier, C. J.; Ince, C.

    2002-01-01

    This study examined whether different durations of ischaemia (I) and reperfusion (R) altered the kinetics of O-2 consumption-to-demand matching and the contribution of changes in calcium and metabolic pathways to possible alterations. The response time of mitochondrial O-2 consumption (t(mito)) to a

  9. Zależność bodźcowości ciśnienia od cyrkulacji atmosferycznej w Warszawie

    Directory of Open Access Journals (Sweden)

    Katarzyna Rozbicka

    2016-09-01

    Full Text Available W pracy zbadano: czasowy rozkład ciśnienia atmosferycznego, bodźcowe oddziaływanie ciśnienia atmosferycznego o wartościach wyższych od 1015 hPa lub niższych od 985 hPa. Wyznaczono częstość i prawdopodobieństwo wystąpienia ciśnienia o oddziaływaniu bodźcowym oraz zanalizowano zależność zmian międzydobowych ciśnienia od typów cyrkulacji atmosferycznej według klasyfikacji Lityńskiego. Do obliczeń wykorzystano cogodzinne wartości ciśnienia atmosferycznego pochodzące ze stacji Ursynów SGGW z okresu 2011–2015. Na podstawie badań stwierdzono, że ciśnienie atmosferyczne o oddziaływaniu bodźcowym w Warszawie może wystąpić w każdym miesiącu z prawdopodobieństwem od 0,2% do 19,1%, w przypadku ciśnienia o wartościach wyższych niż 1015 hPa oraz od 0,1 do 3,4%, w przypadku ciśnienia niższego od 985 hPa, z wyjątkiem czerwca i sierpnia. Zmiany międzydobowe ciśnienia atmosferycznego mogą osiągać około 24 hPa, a częstość występowania bodźców „silnych” wywołanych tymi zmianami wyniosła w poszczególnych miesiącach od 1% do 16%, natomiast bodźców „bardzo silnych” od 2% do 8%. Spośród sytuacji synoptycznych największe znaczenie dla bodźcowości zmian ciśnienia mają sytuacje cyklonalne: szczególnie przy adwekcji powietrza z sektora północno-zachodniego (NWC.

  10. Biodegradation of BOD and ammonia-free using bacterial consortium in aerated fixed film bioreactor (AF2B)

    Science.gov (United States)

    Prayitno, Rulianah, Sri; Saroso, Hadi; Meilany, Diah

    2017-06-01

    BOD and Ammonia-free (NH3-N) are pollutants of hospital wastewater which often exceed the quality standards. It is because biological processes in wastewater treatment plant (WWTP) have not been effective in degrading BOD and NH3-N. Therefore, a study on factors that influence the biodegradation of BOD and NH3-N by choosing the type of bacteria to improve the mechanisms of biodegradation processes is required. Bacterial consortium is a collection of several types of bacteria obtained from isolation process, which is known to be more effective than a single bacterial in degrading pollutants. On the other hand, AF2B is a type of reactor in wastewater treatment system. The AF2B contains a filter media that has a large surface area so that the biodegradation process of pollutants by microorganism can be improved. The objective of this research is to determine the effect of volume of starter and air supplies on decreasing BOD and NH3-N in hospital wastewater using bacterial consortium in the AF2B on batch process. The research was conducted in three stages: the making of the growth curve of the bacterial consortium, bacterial consortium acclimatization, and hospital wastewater treatment in the AF2B with batch process. The variables used are the volume of starter (65%, 75%, and 85% in volume) and air supplies (2.5, 5, and 7.5 L/min). Meanwhile, the materials used are hospital wastewater, bacterial consortium (Pseudomonas diminuta, Pseudomonas capica, Bacillius sp, and Nitrobacter sp), blower, and AF2B. AF2B is a plastic basin containing a filter media with a wasp-nest shape used as a medium for growing the bacterial consortium. In the process of making the growth curve, a solid form of bacterial consortium was dissolved in sterilized water, then grown in a nutrient broth (NB). Then, shaking and sampling were done at any time to determine the path growth of bacterial consortium. In the acclimatization process, bacterial isolates were grown using hospital wastewater as a

  11. Pengaruh Laju Alir Inlet Reaktor MSL terhadap Reduksi BOD, COD, TSS, dan Minyak/Lemak Limbah Cair Industri Minyak Goreng

    Directory of Open Access Journals (Sweden)

    Salmariza Sy

    2017-06-01

    Full Text Available This research was conducted by treating edible oil industry wastewater used Multi Soil Layering (MSL method. The MSL reactor was built from a 200x120x200 cm concrete basin. Andisol soil was mixed with sawdust and fine charcoal at each ratio 5:1:1 based on dry weight as an impermeable layer. The flow rate variations were 250, 500, 1000, and 1500 L/m2.day. The observed pollutant parameters were BOD, COD, TSS, oil/fat, and pH. The results showed that MSL reactor was effective to decrease the pollutant content of edible oil industry wastewater. The reactor could reduce concentration of effluent parameters below standard except for oil/fat parameters at high flow rates. In the effluent was found BOD 0.66-14.22 mg/L, COD 5-69 mg/L, TSS 9-26 mg/L, and oil/fat 2-9 mg/L. The flow rate had an effect on reduction efficiency of BOD, COD, TSS, and oil/fat but did not effect pH as all flow rate could raise pH 6.37-6.95 became pH 6.99-7.24. The lower the flow rate the higher the reduction efficiency. The reduction efficiency at flow rates 250 and 1500 L/m2 days for BOD were 99% and 86%, COD were 96% and 71%, TSS were 88% and 77%, and oil/fat were 80% and 60%.ABSTRAK  Penelitian ini dilakukan dengan mengolah air limbah industri minyak goreng menggunakan metoda Multi Soil Layering (MSL. Reaktor MSL dibuat dari beton berbentuk bak ukuran 200x120x200 cm. Tanah andisol dicampur dengan serbuk gergaji dan arang halus pada rasio masing-masing 5:1:1 berdasarkan berat kering sebagai penyusun lapisan impermeable. Variasi laju alir yaitu 250, 500, 1000, dan 1500 L/m2.hari. Parameter pencemar yang dianalisis meliputi BOD, COD, TSS, minyak/lemak, dan pH. Hasil penelitian menunjukkan bahwa reaktor MSL sangat efektif untuk menurunkan kandungan zat pencemar limbah cair industri minyak goreng. Reaktor dapat mereduksi konsentrasi parameter outlet sampai dibawah baku mutu yang distandarkan kecuali untuk parameter miyak/lemak pada perlakuan laju alir tinggi. Pada effluen

  12. Ventilatory accommodation of oxygen demand and respiratory water loss in kangaroos from mesic and arid environments, the eastern grey kangaroo (Macropus giganteus) and the red kangaroo (Macropus rufus).

    Science.gov (United States)

    Dawson, T J; Munn, A J; Blaney, C E; Krockenberger, A; Maloney, S K

    2000-01-01

    We studied ventilation in kangaroos from mesic and arid environments, the eastern grey kangaroo (Macropus giganteus) and the red kangaroo (Macropus rufus), respectively, within the range of ambient temperatures (T(a)) from -5 degrees to 45 degrees C. At thermoneutral temperatures (Ta=25 degrees C), there were no differences between the species in respiratory frequency, tidal volume, total ventilation, or oxygen extraction. The ventilatory patterns of the kangaroos were markedly different from those predicted from the allometric equation derived for placentals. The kangaroos had low respiratory frequencies and higher tidal volumes, even when adjustment was made for their lower basal metabolism. At Ta>25 degrees C, ventilation was increased in the kangaroos to facilitate respiratory water loss, with percent oxygen extraction being markedly lowered. Ventilation was via the nares; the mouth was closed. Differences in ventilation between the two species occurred at higher temperatures, and at 45 degrees C were associated with differences in respiratory evaporative heat loss, with that of M. giganteus being higher. Panting in kangaroos occurred as a graded increase in respiratory frequency, during which tidal volume was lowered. When panting, the desert red kangaroo had larger tidal volumes and lower respiratory frequencies at equivalent T(a) than the eastern grey kangaroo, which generally inhabits mesic forests. The inference made from this pattern is that the red kangaroo has the potential to increase respiratory evaporative heat loss to a greater level.

  13. Burden of disease calculation, cost of illness analysis and demand ...

    African Journals Online (AJOL)

    The paper introduces the demand for death for Activities of Daily Living (ADL) measured disability as being pioneered by Igberaese and co-workers, as a way of eliminating the BoD and CoI once and for all. It makes DALY only equal to YLL, as YLD approaches zero. DALY will simply be the number of years of life lost due to ...

  14. Demand Uncertainty

    DEFF Research Database (Denmark)

    Nguyen, Daniel Xuyen

    This paper presents a model of trade that explains why firms wait to export and why many exporters fail. Firms face uncertain demands that are only realized after the firm enters the destination. The model retools the timing of uncertainty resolution found in productivity heterogeneity models....... This retooling addresses several shortcomings. First, the imperfect correlation of demands reconciles the sales variation observed in and across destinations. Second, since demands for the firm's output are correlated across destinations, a firm can use previously realized demands to forecast unknown demands...... in untested destinations. The option to forecast demands causes firms to delay exporting in order to gather more information about foreign demand. Third, since uncertainty is resolved after entry, many firms enter a destination and then exit after learning that they cannot profit. This prediction reconciles...

  15. Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

    Science.gov (United States)

    Tegen, I.; Heinold, B.; Todd, M.; Helmert, J.; Washington, R.; Dubovik, O.

    2006-09-01

    We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via self-abrasion of saltating diatomite flakes in the Bodélé, the emission model based on the assumption of dust production by saltation and using observed surface wind speeds as input parameters reproduces observed dust optical thicknesses well. Although the peak wind speeds in the regional model underestimate the highest wind speeds occurring on 10-12 March 2005, the spatio-temporal evolution of the dust cloud can be reasonably well reproduced by this model. Dust aerosol interacts with solar and thermal radiation in the regional model; it is responsible for a decrease in maximum daytime temperatures by about 5 K at the beginning the dust storm on 10 March 2005. This direct radiative effect of dust aerosol accounts for about half of the measured temperature decrease compared to conditions on 8 March. Results from a global dust model suggest that the dust from the Bodélé is an important contributor to dust crossing the African Savannah region towards the Gulf of Guinea and the equatorial Atlantic, where it can contribute up to 40% to the dust optical thickness.

  16. Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

    Directory of Open Access Journals (Sweden)

    I. Tegen

    2006-01-01

    Full Text Available We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via self-abrasion of saltating diatomite flakes in the Bodélé, the emission model based on the assumption of dust production by saltation and using observed surface wind speeds as input parameters reproduces observed dust optical thicknesses well. Although the peak wind speeds in the regional model underestimate the highest wind speeds occurring on 10–12 March 2005, the spatio-temporal evolution of the dust cloud can be reasonably well reproduced by this model. Dust aerosol interacts with solar and thermal radiation in the regional model; it is responsible for a decrease in maximum daytime temperatures by about 5 K at the beginning the dust storm on 10 March 2005. This direct radiative effect of dust aerosol accounts for about half of the measured temperature decrease compared to conditions on 8 March. Results from a global dust model suggest that the dust from the Bodélé is an important contributor to dust crossing the African Savannah region towards the Gulf of Guinea and the equatorial Atlantic, where it can contribute up to 40% to the dust optical thickness.

  17. Pengaruh Jumlah Eceng Gondok(eichornia Crassipes) Dan Waktu Tinggal Terhadappenurunan Konsentrasi Cod, Bod, Dan Warnadalam Limbah Batik

    OpenAIRE

    Wahyu A, Diah; Syafrudin, Syafrudin; Zaman, Badrus

    2015-01-01

    Batik industries is one of any industries that produce wastewater. According to the previous researches, also known that wastewater of batik industries contain organic substances, suspended solid, color, chromium, phenol, and other. Result of the characteristic test show that BOD concentration is about 130,37 mg/l, COD 1376,29 mg/l, also color 10.000 mg/l PtCo. Treatment for wastewater of batik industries is needed since wastewater can be harm to the environment and it can decrease the enviro...

  18. Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

    OpenAIRE

    I. Tegen; B. Heinold; M. Todd; J. Helmert; R. Washington; O. Dubovik; O. Dubovik

    2006-01-01

    We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via self-abras...

  19. Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

    OpenAIRE

    Tegen , I.; Heinold , B.; Todd , M.; Helmert , J.; Washington , R.; Dubovik , O.

    2006-01-01

    International audience; We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust producti...

  20. Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

    OpenAIRE

    R. Washington; J. Helmert; M. Todd; B. Heinold; I. Tegen; O. Dubovik

    2006-01-01

    We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via ...

  1. Lipid production from tapioca wastewater by culture of Scenedesmus sp. with simultaneous BOD, COD and nitrogen removal

    Science.gov (United States)

    Romaidi; Hasanudin, Muhammad; Kholifah, Khusnul; Maulidiyah, Alik; Putro, Sapto P.; Kikuchi, Akira; Sakaguchi, Toshifumi

    2018-05-01

    The use of microalgae to produce biodiesel or possibly remove nutrients from industrial wastewater has gained important attention during recent years due to their photosynthetic rate and its versatile nature to grow in various wastewater systems. In this study, a microalgae, Scenedesmus sp., was cultured to enhance the lipid production and nutrients removal from tapioca wastewater sample. To assess lipid production, Scenedesmus sp. was cultured in different concentration of tapioca wastewater sample (from 0 to 100 %), and nutrient removal including BOD, COD, NH4, NO2, NO3 level by Scenedesmus sp. was assessed in 100% of tapioca wastewater culture. After 8 days of culture, it was found out that 50% of tapioca wastewater sample resulted in highest concentration of lipid content than that of the other concentrations. The level of environment indicator as nutrient removal such as BOD, COD, NH4, NO2, NO3 were also decreased up to 74%, 72%, 95%, 91%, and 91%, respectively. The pH condition changed from initial condition acidic (pH: 4) to neutral or basic condition (pH: 7-8) as recommended in wastewater treatment system. This research provided a novel approach and achieved efficient simultaneous lipid production and nutrients removal from tapioca wastewater sample by Scenedesmus’s culture system.

  2. Quantification of the inert chemical oxygen demand of raw wastewater and evaluation of soluble microbial product production in demo-scale upflow anaerobic sludge blanket reactors under different operational conditions.

    Science.gov (United States)

    Aquino, Sergio F; Gloria, Roberto M; Silva, Silvana Q; Chernicharo, Carlos A L

    2009-06-01

    This paper investigates the production of soluble microbial products (SMPs) in demonstration-scale upflow anaerobic sludge blanket reactors operated under different conditions and fed with raw wastewater. The results showed that 9.2 +/- 1.3% of the influent soluble chemical oxygen demand (COD) could be considered inert to anaerobic treatment and that the amount of COD produced by biomass varied from 30 to 70 mg x L(-1), accounting for 45 to 63% of the soluble effluent COD. The accumulation of SMP appeared to be dependent on the hydraulic retention time (HRT) applied to the reactors, with a larger accumulation of SMP observed at the lowest HRT (5 hours); this may have been due to stress conditions caused by high upflow velocity (1.1 m x h(-1)). In terms of residual COD characterization, ultrafiltration results showed that higher amounts of high molecular weight compounds were found when HRT was the lowest (5 hours), and that the molecular weight distribution depended on the operational condition of the reactors. Biodegradability tests showed that the low and high molecular weight SMPs were only partially degraded anaerobically (10 to 60%) and that the high molecular weight SMPs were difficult to degrade aerobically.

  3. Biogas Production and Removal COD – BOD and TSS from Wastewater Industrial Alcohol (Vinasse by Modified UASB Bioreactor

    Directory of Open Access Journals (Sweden)

    Utami Isni

    2016-01-01

    Full Text Available Biogas production and decreased organic loading of vinasse using a modified UASB bioreactor has been done successfully. Vinasse is waste from the ethanol industry which contains COD: 9.360 mg / L , BOD : 4.013 mg/L, and TSS: 317.5 mg/L. The purpose of this research was to study the performance of bioreactors Upflow Anaerobic Sludge Blanket (UASB to decompose the vinasse into biogas or methane. UASB operating principle is to distribute wastewater in the bioreactor to flow upward through the sludge blanket by setting the hidrolic retention time (HRT. Four UASB bioreactor columns were used in this experiment wherein each with a capacity of 50 L in volume; 23 cm inside diameter, and 120 cm. The variations of hydraulic capacity followed the variations of HRT in the range of 72-36 hours. Modifications were carried out on the top of column UASB with the aim of preventing gas losses and increasing the flowrate of gas out from the top of the column. The results showed that HRT increased from 36 h to 72 h followed by an increase in COD removal efficiency of 55.64% to 66.81%; BOD5 from 67.85% to 74.58%; and TSS from 66.69% to 84.19%. The maximum volume of biogas produced was in the range of 5.826 L / day (42.89% methane to 7.930 L / day (methane 58.06%.

  4. Oxygen therapy reduces postoperative tachycardia

    DEFF Research Database (Denmark)

    Stausholm, K; Kehlet, H; Rosenberg, J

    1995-01-01

    Concomitant hypoxaemia and tachycardia in the postoperative period is unfavourable for the myocardium. Since hypoxaemia per se may be involved in the pathogenesis of postoperative tachycardia, we have studied the effect of oxygen therapy on tachycardia in 12 patients randomly allocated to blinded...... air or oxygen by facemask on the second or third day after major surgery. Inclusion criteria were arterial hypoxaemia (oxygen saturation 90 beat.min-1). Each patient responded similarly to oxygen therapy: an increase in arterial oxygen saturation and a decrease...... in heart rate (p oxygen has a positive effect on the cardiac oxygen delivery and demand balance....

  5. [Domiciliary oxygen therapy].

    Science.gov (United States)

    Abdel Kafi, S

    2010-09-01

    In Belgium, oxygen therapy is becoming more and more accessible. When oxygen is needed for short periods or for special indications as palliative care, an agreement between mutual insurance companies and pharmacists allows the practitioner the home installation of gazeous oxygen cylinder or of oxygen concentrator. When long term oxygen therapy (LTOT) is indicated for patients with respiratory insufficiency, the pneumologist must first ask the INAMI the authorization to install one of the following modalities: oxygen concentrator with or without demand oxygen delivery cylinder and liquid oxygen. The goal of LTOT is to increase survival and quality of life. The principal and well accepted indication for LTOT is severe hypoxemia. The beneficial effects of oxygen therapy limited at night or on exertion are controversial. In order to increase patient's autonomy, oxygen can be prescribed for ambulation, respecting prescription's rules. At each step of oxygen therapy implementing (indication, choice of the device and follow-up) the patient under oxygen may benefit from a joint approach between the general practitioner and the chest specialist.

  6. In demand

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, B. [Bridgestone Ltd. (United Kingdom)

    2005-11-01

    The paper explains how good relationships can help alleviate potential tyre shortages. Demand for large dump truck tyres (largely for China) has increased by 50% within 12 months. Bridgestone's manufacturing plants are operating at maximum capacity. The company supplies tyres to all vehicles at Scottish Coal's opencast coal mines. Its Tyre Management System (TMS) supplied free of charge to customers helps maximise tyre life and minimise downtime from data on pressure, tread and general conditions fed into the hand-held TMS computer. 3 photos.

  7. Treatment of sludge containing nitro-aromatic compounds in reed-bed mesocosms – Water, BOD, carbon and nutrient removal

    International Nuclear Information System (INIS)

    Gustavsson, L.; Engwall, M.

    2012-01-01

    Highlights: ► It is necessary to improve existing and develop new sludge management techniques. ► One method is dewatering and biodegradation of compounds in constructed wetlands. ► The result showed high reduction of all tested parameters after treatment. ► Plants improve degradation and Phragmites australis is tolerant to xenobiotics. ► The amount of sludge could be reduced by 50–70%. - Abstract: Since the mid-1970s, Sweden has been depositing 1 million ton d.w sludge/year, produced at waste water treatment plants. Due to recent legislation this practice is no longer a viable method of waste management. It is necessary to improve existing and develop new sludge management techniques and one promising alternative is the dewatering and treatment of sludge in constructed wetlands. The aim of this study was to follow reduction of organic carbon, BOD and nutrients in an industrial sludge containing nitro-aromatic compounds passing through constructed small-scale wetlands, and to investigate any toxic effect such as growth inhibition of the common reed Phragmites australis. The result showed high reduction of all tested parameters in all the outgoing water samples, which shows that constructed wetlands are suitable for carbon and nutrient removal. The results also showed that P. australis is tolerant to xenobiotics and did not appear to be affected by the toxic compounds in the sludge. The sludge residual on the top of the beds contained low levels of organic carbon and is considered non-organic and could therefore be landfilled. Using this type of secondary treatment method, the amount of sludge could be reduced by 50–70%, mainly by dewatering and biodegradation of organic compounds.

  8. Ọmọ̀jọ́lá, Bodé. Yorùbá Music in the Twentieth Century: Identity, Agency and Performance Practice

    OpenAIRE

    Vallier, Gilles-Félix

    2017-01-01

    Ọmọ̀jọ́lá, Bodé. — Yorùbá Music in the Twentieth Century : Identity, Agency and Performance Practice. New York, University of Rochester Press ; Eastman, Rochester Studies in Ethnomusicology, 2012, 285 p., bibl., ill., CD. Yorùbá Music in the Twentieth Century de Bodé Ọmọ̀jọ́lá déconstruit efficacement la notion d'une culture musicale yorùbá singulière, découvrant à la place une tapisserie pittoresque de traditions socialement et esthétiquement diverses, lesquelles sont unies, dans bien des ...

  9. THE USE OF SILICA SAND, ZEOLITE AND ACTIVE CHARCOAL TO REDUCE BOD, COD AND TSS OF LAUNDRY WASTE WATER AS A BIOLOGY LEARNING RESOURCES

    Directory of Open Access Journals (Sweden)

    Moch Assiddieq

    2017-11-01

    Full Text Available The aquatic environment contaminated with detergent waste in high concentrations can endanger the lives human and biota in the water. This study aimed to determine the decrease of BOD, COD and TSS content of laundry liquid waste by using filter media of silica sand, zeolite, and activated charcoal. Filter medium 1a can reduce BOD level from 98.6 mg/L to 58.80 mg/L (40.36%, while medium 1b can decrease BOD level to 21.20 mg/L (78.48%. It showed that media 1a had not fulfilled the quality standard of BOD of waste water that is 50 mg/L, while media 1b had fulfilled the standard of quality. Filter media 1a can decrease COD level from 210 mg/L to 78.80 mg/L (62.47%, whereas medium 1b can decrease COD to 25.60 mg/L (87.80%. This showed that media 1a and media 1b had met the quality standard of COD of waste water that is 100 mg/L. Filter media 1a can decrease TSS level from 465 mg/L to 122.5 mg/L (73.65%, whereas medium 1b can decrease TSS level to 52.3 mg/L (88.75%. This showed that media 1a and media 1b had met the quality standard of TSS of waste water that is 150 mg/L.

  10. THE EFFECT OF INFLUENT CONCENTRATION AND HYDRAULIC LOADING RATE (HLR TO BOD AND COD REMOVAL ON ARTIFICIAL DOMESTIC WASTEWATER TREATMENT (GREY WATER USING UASB REACTOR

    Directory of Open Access Journals (Sweden)

    Syafrudin Syafrudin

    2014-05-01

    Full Text Available Upflow anaerobic sludge blanket (UASB reactor is one of anaerobic biological treatment was develop in late 1970’s. UASB reactor is suitable for the tropic areas because it has a high temperature about 20°-30°C. Domestic wastewater is divided into two types, namely black water and grey water. But in this case used domestic grey water. Grey water is household wastewater from showers, sinks and kitchen. Grey water has a total 75% of the domestic wastewater volume. The research was conducted in laboratory scale. This study performed a variation of Hydraulic Loading Rate (HLR and the influent concentration. There were 25 reactors include 5 variations of influent concentration and 5 Hydraulic Loading Rate’s (HLR variation. The research could asses BOD5 and COD removal with treatment in UASB. Efficiency of BOD5 removal by varying the influent concentration and HLR was about 38%-75% and COD was about 40%-77%. The lower concentration could be increase efficiency BOD5 and COD removal. Influent concentration optimum occurred when middle concentration was about 840 mg/L COD and HLR optimum was 0,05 m3/m2/hour.

  11. Oxygen therapy for cluster headache

    DEFF Research Database (Denmark)

    Petersen, Anja S; Barloese, Mads Cj; Lund, Nunu Lt

    2017-01-01

    -controlled, crossover inpatient study, and 102 CH attacks were treated with 100% oxygen delivered by demand valve oxygen (DVO), O2ptimask or simple mask (15 liters/min) or placebo delivered by DVO for 15 minutes. Primary endpoint: Two-point decrease of pain on a five-point rating scale within 15 minutes. Results Only...

  12. Oxygen toxicity

    Directory of Open Access Journals (Sweden)

    C. A. van der Westhuizen

    1990-07-01

    Full Text Available Oxygen has been discovered about 200 years ago. Since then the vital physiological involvement of oxygen in various biologi­cal processes, mainly energy production, has been established. However, in the body molecular oxygen can be converted to toxic oxygen metabolites such as superoxide anion, hydrogen peroxide, the hydroxyl radical and singlet oxygen. These toxic metabolites are produced mainly in the mitochondria, plasma membranes and endoplasmic reticulum.

  13. Future butanes supply/demand

    International Nuclear Information System (INIS)

    Whitley, S.C.

    1992-01-01

    This paper graphically depicts, through in-depth supply/demand analysis, how environmental regulations can be both bad and good for an industry. In the case of n-butane, the Environmental Protection Agency (EPA) summertime gasoline volatility regulations are a culprit - threatening to ultimately destroy refinery demand for the product as a gasoline blendstock. Waiting in the wings are environmental regulations that should eventually prove to be n-butane's savior. The regulations referred to here are the Clean Air Act (CAA) of 1990's mandate for motor fuel oxygenates. The negative impact of gasoline volatility regulations on U.S. n-butane demand and the positive impact that should come from the use of n-butane as a MTBE precursor are covered. Many variables exist which make studying the effects of these environmental regulations very difficult. Over the past three years RPC Group has conducted numerous studies on n-butane supply/demand, as impacted by both EPA gasoline volatility and fuel oxygenate regulations

  14. Analysis of tannery effluents from the Challawa industrial estate in ...

    African Journals Online (AJOL)

    Global Journal of Pure and Applied Sciences ... and some physicochemical parameters such as conductivity, solids, chloride, chromium, alkalinity, sulphide, chemical oxygen demand, COD, and biochemical oxygen demand, BOD, of the waste water were determined. ... Keywords: tannery, effluent, pollution, environment

  15. Dynamic of the structure and biodiversity of macrozoobenthos in one ...

    African Journals Online (AJOL)

    xiongjing

    2012-07-10

    Jul 10, 2012 ... oxygen demand; BOD, biochemical oxygen demand. cause a diverse range of .... deterministic factors determining the elimination or replacement of species .... need for new approaches and concepts. Glob. Change Biol.

  16. Pemanfaatan Abu Tandan Kosong Kelapa Sawit Untuk Menurunkan Kandungan Minyak/Lemak BOD Dan COD Dari Limbah Cair Pabrik Kelapa Sawit

    OpenAIRE

    Sari, Riris Duma

    2011-01-01

    An investigation of the utilization of oil palm empty fruit bunch ash to reduce the content of oil/grease, BOD and COD from oil mill effluent. Samples of palm oil mill effluent from wastewater treatment plant of PT Nusantara IV (Persero) oil processing unit sopsa of Padang Lawas district. Samples taken from the last pond will be discharged into the environment. Empty Fruit of Oil Palm Ash taken from the kitchen burning empty fruit bunches PT Nusantara IVB (Persero) units Sosa of Padang Law...

  17. Oxygen requirements of the earliest animals

    DEFF Research Database (Denmark)

    Mills, Daniel Brady; Ward, Lewis M.; Jones, CarriAyne

    2014-01-01

    likely exhibited a physiology and morphology similar to that of a modern sponge, its oxygen demands may have been met well before the enhanced oxygenation of the Ediacaran Period. Therefore, the origin of animals may not have been triggered by a contemporaneous rise in the oxygen content...

  18. Oxygen Therapy

    Science.gov (United States)

    ... their breathing to dangerously low levels. Will I need oxygen when I sleep? Usually if you use supplemental oxygen during the ... your health care provider tells you you only need to use oxygen for exercise or sleep. Even if you feel “fine” off of your ...

  19. Oxygen Therapy

    Directory of Open Access Journals (Sweden)

    Bonnie Solmes

    2000-01-01

    Full Text Available LTOT is prescribed for people with chronic lung disease in whom there is a decrease in the ability of the lungs to supply enough oxygen to the body. The heart is obliged to pump faster to meet the body's oxygen requirements. This may place undue stress on the heart, resulting in palpitations, dizziness and fatigue. A low oxygen level in arterial blood is also harmful to the heart, the brain and the pulmonary blood vessels. Oxygen therapy is used to break this cycle. A person with low blood oxygen will often be able to accomplish more with less fatigue with the help of supplemental oxygen therapy. Shortness of breath is a mechanical problem resulting from the effects of chronic obstructive pulmonary disease. Oxygen therapy may or may not reduce shortness of breath, but it will help the lungs and heart to function with less stress.

  20. Oxygenates to hike gasoline price

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper reports that cost of achieving required US gasoline formulations this winter in Environmental Protection Agency carbon monoxide (CO) nonattainment areas could reach 3-5 cents/gal, an Energy Information Administration analysis has found. EIA says new winter demand for gasoline blending oxygenates such as methyl tertiary butyl ether (MTBE) or ethanol created by 190 amendments to the Clean Air Act (CAA) will exceed US oxygenate production by 140,000-220,000 b/d. The shortfall must be made up from inventory or imports. EIA estimates the cost of providing incremental oxygenate to meet expected gasoline blending demand likely will result in a price premium of about 20 cents/gal of MTBE equivalent over traditional gasoline blend octane value. That cost likely will be added to the price of oxygenated gasoline

  1. Enraizamento de estacas lenhosas de pereira tratadas com AIB e mantidas em ambiente de estufa tipo B.O.D. e de telado Rooting of hardwood cuttings of pear tree with IBA under B.O.D. chamber and greenhouse environment

    Directory of Open Access Journals (Sweden)

    Wilson Barbosa

    2007-01-01

    Full Text Available Pesquisou-se o enraizamento da pereira em ambiente controlado de estufa tipo B.O.D. e em telado simples. Utilizou-se a cultivar híbrida 'Limeira', destinada exclusivamente para fins culinários e para porta-enxerto. Estacas lenhosas sem folhas, medindo 25 cm de comprimento, foram tratadas com ácido indolbutírico (AIB nas concentrações de 0; 2.000; 4.000 e 6.000 mg.L-1 por 10 segundos. Como substrato, utilizou-se da mistura de vermiculita e areia grossa (2:1 v/v, sendo a mesma umedecida com meio contendo solução salina MS e sacarose 1%. As estacas permaneceram por 42 dias dentro de estufas tipo B.O.D. (temperatura de 25ºC, umidade relativa do ar de 90% e fotoperíodo de 8 horas e de telado com irrigação por microaspersão, sem controle ambiental. Em ambiente controlado de estufa, as estacas não-tratadas com AIB iniciaram intensa brotação das gemas e formação de calo após sete dias do plantio. Já em ambiente de telado, essas estacas demoraram 21 dias para o início de brotação das gemas, mostrando menor desenvolvimento de calo. Nas estacas tratadas com AIB, os calos surgiram nas regiões dos cortes após o terceiro dia de incubação na estufa B.O.D. As raízes desenvolveram-se a partir dos tecidos da base e dos calos, tornando-se mais nítidas a partir de 14 e 28 dias, respectivamente, para os ambientes de estufa e de telado. Após 42 dias, o melhor percentual de enraizamento (83% foi verificado no tratamento com AIB a 2.000 mg.L-1, em ambiente de estufa B.O.D. O emprego dessa estufa, com temperatura, luz e umidade relativa controladas, mostrou-se viável em relação ao telado, no processo de enraizamento das estacas lenhosas da pereira 'Limeira', podendo favorecer o sistema de propagação vegetativa da pereira e encurtar o período da formação de mudas.The rooting of cuttings pear under controlled environment of chamber (B.O.D. type and greenhouse was searched. Hardwood cuttings of 'Limeira' pear, without leaves, measuring

  2. On-Demand Telemetry

    Data.gov (United States)

    National Aeronautics and Space Administration — AFRC has previously investigated the use of Network Based Telemetry. We will be building on that research to enable On-Demand Telemetry. On-Demand Telemetry is a way...

  3. Money Demand in Latvia

    OpenAIRE

    Ivars Tillers

    2004-01-01

    The econometric analysis of the demand for broad money in Latvia suggests a stable relationship of money demand. The analysis of parameter exogeneity indicates that the equilibrium adjustment is driven solely by the changes in the amount of money. The demand for money in Latvia is characterised by relatively high income elasticity typical for the economy in a monetary expansion phase. Due to stability, close fit of the money demand function and rapid equilibrium adjustment, broad money aggreg...

  4. Electricity demand forecasting techniques

    International Nuclear Information System (INIS)

    Gnanalingam, K.

    1994-01-01

    Electricity demand forecasting plays an important role in power generation. The two areas of data that have to be forecasted in a power system are peak demand which determines the capacity (MW) of the plant required and annual energy demand (GWH). Methods used in electricity demand forecasting include time trend analysis and econometric methods. In forecasting, identification of manpower demand, identification of key planning factors, decision on planning horizon, differentiation between prediction and projection (i.e. development of different scenarios) and choosing from different forecasting techniques are important

  5. Ethanol Demand in United States Gasoline Production

    Energy Technology Data Exchange (ETDEWEB)

    Hadder, G.R.

    1998-11-24

    The Oak Ridge National Laboratory (OWL) Refinery Yield Model (RYM) has been used to estimate the demand for ethanol in U.S. gasoline production in year 2010. Study cases examine ethanol demand with variations in world oil price, cost of competing oxygenate, ethanol value, and gasoline specifications. For combined-regions outside California summer ethanol demand is dominated by conventional gasoline (CG) because the premised share of reformulated gasoline (RFG) production is relatively low and because CG offers greater flexibility for blending high vapor pressure components like ethanol. Vapor pressure advantages disappear for winter CG, but total ethanol used in winter RFG remains low because of the low RFG production share. In California, relatively less ethanol is used in CG because the RFG production share is very high. During the winter in California, there is a significant increase in use of ethanol in RFG, as ethanol displaces lower-vapor-pressure ethers. Estimated U.S. ethanol demand is a function of the refiner value of ethanol. For example, ethanol demand for reference conditions in year 2010 is 2 billion gallons per year (BGY) at a refiner value of $1.00 per gallon (1996 dollars), and 9 BGY at a refiner value of $0.60 per gallon. Ethanol demand could be increased with higher oil prices, or by changes in gasoline specifications for oxygen content, sulfur content, emissions of volatile organic compounds (VOCS), and octane numbers.

  6. Biotechnological sulphide removal with oxygen

    NARCIS (Netherlands)

    Buisman, C.

    1989-01-01

    This thesis deals with the development of a new process for biotechnological sulphide removal from wastewater, in which it is attempted to convert sulphide into elemental sulphur by colourless sulphur bacteria. The toxicity, corrosive properties, unpleasant odor and high oxygen demand of sulphide

  7. Electricity demand in Kazakhstan

    International Nuclear Information System (INIS)

    Atakhanova, Zauresh; Howie, Peter

    2007-01-01

    Properties of electricity demand in transition economies have not been sufficiently well researched mostly due to data limitations. However, information on the properties of electricity demand is necessary for policy makers to evaluate effects of price changes on different consumers and obtain demand forecasts for capacity planning. This study estimates Kazakhstan's aggregate demand for electricity as well as electricity demand in the industrial, service, and residential sectors using regional data. Firstly, our results show that price elasticity of demand in all sectors is low. This fact suggests that there is considerable room for price increases necessary to finance generation and distribution system upgrading. Secondly, we find that income elasticity of demand in the aggregate and all sectoral models is less than unity. Of the three sectors, electricity demand in the residential sector has the lowest income elasticity. This result indicates that policy initiatives to secure affordability of electricity consumption to lower income residential consumers may be required. Finally, our forecast shows that electricity demand may grow at either 3% or 5% per year depending on rates of economic growth and government policy regarding price increases and promotion of efficiency. We find that planned supply increases would be sufficient to cover growing demand only if real electricity prices start to increase toward long-run cost-recovery levels and policy measures are implemented to maintain the current high growth of electricity efficiency

  8. Innovation and Demand

    DEFF Research Database (Denmark)

    Andersen, Esben Sloth

    2007-01-01

    the demand-side of markets in the simplest possible way. This strategy has allowed a gradual increase in the sophistication of supply-side aspects of economic evolution, but the one-sided focus on supply is facing diminishing returns. Therefore, demand-side aspects of economic evolution have in recent years...... received increased attention. The present paper argues that the new emphasis on demand-side factors is quite crucial for a deepened understanding of economic evolution. The major reasons are the following: First, demand represents the core force of selection that gives direction to the evolutionary process....... Second, firms' innovative activities relate, directly or indirectly, to the structure of expected and actual demand. Third, the demand side represents the most obvious way of turning to the much-needed analysis of macro-evolutionary change of the economic system....

  9. PERFECT DEMAND ILLUSION

    Directory of Open Access Journals (Sweden)

    Alexander Yu. Sulimov

    2015-01-01

    Full Text Available The article is devoted to technique «Perfect demand illusion», which allows to strengthen the competitive advantageof retailers. Also in the paper spells out the golden rules of visual merchandising.The definition of the method «Demand illusion», formulated the conditions of its functioning, and is determined by the mainhypothesis of the existence of this method.Furthermore, given the definition of the «Perfect demand illusion», and describes its additional conditions. Also spells out the advantages of the «Perfect demandillusion», before the «Demand illusion».

  10. Divers of Passenger Demand

    OpenAIRE

    Wittmer, Andreas

    2011-01-01

    -Overview drivers of passenger demand -Driver 1: Economic growth in developing countries -Driver 2: International business travel in developed countries -Driver 3: International leisure travel in developed countries

  11. Uranium supply and demand

    Energy Technology Data Exchange (ETDEWEB)

    Spriggs, M J

    1976-01-01

    Papers were presented on the pattern of uranium production in South Africa; Australian uranium--will it ever become available; North American uranium resources, policies, prospects, and pricing; economic and political environment of the uranium mining industry; alternative sources of uranium supply; whither North American demand for uranium; and uranium demand and security of supply--a consumer's point of view. (LK)

  12. Wood supply and demand

    Science.gov (United States)

    Peter J. Ince; David B. McKeever

    2011-01-01

    At times in history, there have been concerns that demand for wood (timber) would be greater than the ability to supply it, but that concern has recently dissipated. The wood supply and demand situation has changed because of market transitions, economic downturns, and continued forest growth. This article provides a concise overview of this change as it relates to the...

  13. An improved solution of first order kinetics for biochemical oxygen ...

    African Journals Online (AJOL)

    This paper evaluated selected Biochemical Oxygen Demand first order kinetics methods. Domesticinstitutional wastewaters were collected twice in a month for three months from the Obafemi Awolowo University, Ile-Ife waste stabilization ponds. Biochemical Oxygen Demand concentrations at different days were determined ...

  14. Oxygen safety

    Science.gov (United States)

    ... sure you have working smoke detectors and a working fire extinguisher in your home. If you move around the house with your oxygen, you may need more than one fire extinguisher in different locations. Smoking can be very dangerous. No one should smoke ...

  15. Oxygen therapy - infants

    Science.gov (United States)

    ... breathe increased amounts of oxygen to get normal levels of oxygen in their blood. Oxygen therapy provides babies with the extra oxygen. Information Oxygen is a gas that the cells in your body need to work properly. The ...

  16. Asian oil demand

    International Nuclear Information System (INIS)

    Fesharaki, F.

    2005-01-01

    This conference presentation examined global oil market development and the role of Asian demand. It discussed plateau change versus cyclical movement in the global oil market; supply and demand issues of OPEC and non-OPEC oil; if high oil prices reduce demand; and the Asian oil picture in the global context. Asian oil demand has accounted for about 50 per cent of the global incremental oil market growth. The presentation provided data charts in graphical format on global and Asia-Pacific incremental oil demand from 1990-2005; Asia oil demand growth for selected nations; real GDP growth in selected Asian countries; and, Asia-Pacific oil production and net import requirements. It also included charts in petroleum product demand for Asia-Pacific, China, India, Japan, and South Korea. Other data charts included key indicators for China's petroleum sector; China crude production and net oil import requirements; China's imports and the share of the Middle East; China's oil exports and imports; China's crude imports by source for 2004; China's imports of main oil products for 2004; India's refining capacity; India's product balance for net-imports and net-exports; and India's trade pattern of oil products. tabs., figs

  17. Chemical Oxygen Demand (COD) Attenuation of Methyl Red in ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Department of Pure & Industrial Chemistry, Faculty of Science , University of ... ABSTRACT: Attenuation of methyl red dyestuff in water was assessed by ... alternative low cost materials (Ahmad et al., 2010, .... ml distilled water as blank was also taken through the .... quality control measures such as washing of glassware,.

  18. Demonstrate a Low Biochemical Oxygen Demand Aircraft Deicing Fluid

    Science.gov (United States)

    2013-03-04

    slipperiness when walking or sliding shoes on pavement . Fluid was observed to lead to significant slipperiness FAIL Fluid has no impact on flight...of the specimens was ground to a 32 micro -inch (µin) finish, wiped clean with methyl ethyl ketone (MEK) and weighed to the nearest milligram (mg) on

  19. Chemical oxygen demand reduction in a whey fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Moresi, M; Colicchio, A; Sansovini, F; Sebastiani, E

    1980-01-01

    The efficiency of COD reduction in the fermentation of whey by Kluyveromyces fragilis IMAT 1872 was studied at various temperatures, lactose concentrations, air dilution ratios, and stirring speeds. Two different optimal sets of these variables were found according to whether the objective was the production of cell mass or the reduction of COD. The 2 sets were then compared to establish a strategy for the industrial development of this fermentation process. The experimental efficiencies of COD removal were submitted to analysis in a composite design. Only the O2 transfer coefficient factor and the stripping factor were significant. Therefore, the observations were fitted with a quadratic expression by using only these factors: the mean std. error was <6%. The yield of cells varied in this fermentation, but this parameter may be particularly useful for analyzing and optimizing any fermentation process when the culture medium is a mixture of carbohydrates or the main substrate is fully utilized during the initial stages of fermentation.

  20. Uranium supply and demand

    International Nuclear Information System (INIS)

    1984-05-01

    This report covers the period 1983 to 1995. It draws together the industry's latest views on future trends in supply and demand, and sets them in their historical context. It devotes less discussion than its predecessors to the technical influences underpinning the Institute's supply and demand forecasts, and more to the factors which influence the market behaviour of the industry's various participants. As the last decade has clearly shown, these latter influences can easily be overlooked when undue attention is given to physical imbalances between supply and demand. (author)

  1. On energy demand

    International Nuclear Information System (INIS)

    Haefele, W.

    1977-01-01

    Since the energy crisis, a number of energy plans have been proposed, and almost all of these envisage some kind of energy demand adaptations or conservation measures, hoping thus to escape the anticipated problems of energy supply. However, there seems to be no clear explanation of the basis on which our foreseeable future energy problems could be eased. And in fact, a first attempt at a more exact definition of energy demand and its interaction with other objectives, such as economic ones, shows that it is a highly complex concept which we still hardly understand. The article explains in some detail why it is so difficult to understand energy demand

  2. Sizewell: UK power demand

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    The Sizewell Inquiry was about whether the next power stations to be built in the UK should be nuclear or coal and, if nuclear, PWRs or AGRs. During the period of the Inquiry forecasts of demand for electricity were low. Now, however, it seems that the forecast demand is much increased. This uncertainty in demand and the wide regional variations are examined in some detail. Facts and figures on electricity sales (area by area) are presented. Also the minutes of supply lost per consumer per year. These show that security of supply is also a problem. It is also shown that the way electricity is used has changed. Whilst electricity generation has been changing to large-scale, centralised power stations the demand patterns may make smaller scale, quickly-constructed units more sensible. The questions considered at the Sizewell Inquiry may, indeed, no longer be the right ones. (UK)

  3. Mathematical modeling of dissolved oxygen in fish ponds ...

    African Journals Online (AJOL)

    Mathematical modeling of dissolved oxygen in fish ponds. WJS Mwegoha, ME Kaseva, SMM Sabai. Abstract. A mathematical model was developed to predict the effects of wind speed, light, pH, Temperature, dissolved carbon dioxide and chemical oxygen demand (COD) on Dissolved Oxygen (DO) in fish ponds. The effects ...

  4. A demanding market

    International Nuclear Information System (INIS)

    Thomas, M.

    1997-01-01

    The article relates to the oil and natural gas market, and it gives a survey of proved reserves at the end of 1996 worldwide. The long term trend of increasing world energy demand has seen a major rise during 1996 when global consumption grew by 3%. But worldwide demand, excluding the Former Soviet Union, shows this figure increasing further to 3.7% for the whole of last year according to statistics. 3 figs

  5. Maximum power demand cost

    International Nuclear Information System (INIS)

    Biondi, L.

    1998-01-01

    The charging for a service is a supplier's remuneration for the expenses incurred in providing it. There are currently two charges for electricity: consumption and maximum demand. While no problem arises about the former, the issue is more complicated for the latter and the analysis in this article tends to show that the annual charge for maximum demand arbitrarily discriminates among consumer groups, to the disadvantage of some [it

  6. Comparison of airline passenger oxygen systems.

    Science.gov (United States)

    Byrne, N J

    1995-08-01

    The principal sources of oxygen for inflight passenger use, scheduled and unscheduled, are examined. Present practices of assessment of the passenger's "fitness to fly" are described. Three partner airlines, British Airways, U.S. Air, and Qantas, catering for more than 8000 oxygen requests annually, are compared. Analysis of customer use suggests that medical oxygen requests are frequently not clinically justified. The growth in demand, for both scheduled and unscheduled use of an expensive resource, supports the need for a "recommended best practice" among carriers. Passengers with respiratory disorders who will most benefit from inflight oxygen are vulnerable either to hypoxia or asthma.

  7. DEVICE FOR CONTROL OF OXYGEN PARTIAL PRESSURE

    Science.gov (United States)

    Bradner, H.; Gordon, H.S.

    1957-12-24

    A device is described that can sense changes in oxygen partial pressure and cause a corresponding mechanical displacement sufficient to actuate meters, valves and similar devices. A piston and cylinder arrangement contains a charge of crystalline metal chelate pellets which have the peculiar property of responding to variations in the oxygen content of the ambient atmosphere by undergoing a change in dimension. A lever system amplifies the relative displacement of the piston in the cylinder, and actuates the controlled valving device. This partial pressure oxygen sensing device is useful in controlled chemical reactions or in respiratory devices such as the oxygen demand meters for high altitude aircraft.

  8. Iron oxide minerals in dust-source sediments from the Bodélé Depression, Chad: Implications for radiative properties and Fe bioavailability of dust plumes from the Sahara

    Science.gov (United States)

    Moskowitz, Bruce M; Reynolds, Richard L.; Goldstein, Harland L.; Beroquo, Thelma; Kokaly, Raymond F.; Bristow, Charlie S

    2016-01-01

    Atmospheric mineral dust can influence climate and biogeochemical cycles. An important component of mineral dust is ferric oxide minerals (hematite and goethite) which have been shown to influence strongly the optical properties of dust plumes and thus affect the radiative forcing of global dust. Here we report on the iron mineralogy of dust-source samples from the Bodélé Depression (Chad, north-central Africa), which is estimated to be Earth’s most prolific dust producer and may be a key contributor to the global radiative budget of the atmosphere as well as to long-range nutrient transport to the Amazon Basin. By using a combination of magnetic property measurements, Mössbauer spectroscopy, reflectance spectroscopy, chemical analysis, and scanning electron microscopy, we document the abundance and relative amounts of goethite, hematite, and magnetite in dust-source samples from the Bodélé Depression. The partition between hematite and goethite is important to know to improve models for the radiative effects of ferric oxide minerals in mineral dust aerosols. The combination of methods shows (1) the dominance of goethite over hematite in the source sediments, (2) the abundance and occurrences of their nanosize components, and (3) the ubiquity of magnetite, albeit in small amounts. Dominant goethite and subordinate hematite together compose about 2% of yellow-reddish dust-source sediments from the Bodélé Depression and contribute strongly to diminution of reflectance in bulk samples. These observations imply that dust plumes from the Bodélé Depression that are derived from goethite-dominated sediments strongly absorb solar radiation. The presence of ubiquitous magnetite (0.002–0.57 wt%) is also noteworthy for its potentially higher solubility relative to ferric oxide and for its small sizes, including PM bioavailability to marine and terrestrial ecosystems.

  9. Long-term oxygen therapy for COPD. Improving longevity and quality of life in hypoxemic patients.

    Science.gov (United States)

    Weg, J G; Haas, C F

    1998-04-01

    Long-term oxygen therapy can increase life expectancy in hypoxemic patients with COPD. Accurate identification of hypoxemia requires arterial blood gas measurements. Pulse oximetry can be used to measure trends in oxygenation, oxygen needs, and oxygen requirements during exercise and sleep. A detailed oxygen prescription indicates: (1) the oxygen dose (L/min), (2) the number of hours per day that oxygen therapy is required, (3) the dose required during exercise, (4) the oxygen supply system: concentrator, compressed gas cylinder, or liquid oxygen reservoir, and (5) the delivery device: nasal cannula, demand-flow device, reservoir cannula, or transtracheal oxygen catheter.

  10. Are macroinvertebrates in high altitude streams affected by oxygen deficiency?

    DEFF Research Database (Denmark)

    Jacobsen, Dean; Rostgaard, S.; Vásconez, J. J.

    2003-01-01

    1. The solubility of oxygen in water increases with decreasing temperature. This has led to a general perception of cold, high mountain streams as more oxygen rich than warmer lowland streams, and that macroinvertebrates inhabiting high altitude streams have had no need to adapt to critical oxygen...... conditions. However, this fails to take into account that oxygen solubility declines with decreasing atmospheric pressure, which may be of importance at high altitudes. 2. Based on samples of macroinvertebrate benthos and in situ measurements of respiratory oxygen demand of macroinvertebrates in small...... the mean weight-specific respiratory rate of macroinvertebrates declined by only 50%, from 400 to 3800 m. We suggest that this disproportionately large gap between availability and demand of oxygen at high altitudes may imply a potential oxygen deficiency for the fauna, and we discuss how oxygen deficiency...

  11. UK Nuclear Workforce Demand

    International Nuclear Information System (INIS)

    Roberts, John

    2017-01-01

    UK Nuclear Sites: DECOMMISSIONING - 26 Magnox Reactors, 2 Fast Reactors; OPERATIONAL - 14 AGRs, 1 PWR; 9.6 GWe Total Capacity. Nuclear Workforce Demand • Total workforce demand is expected to grow from ~88,000 in 2017 to ~101,000 in 2021 • Average “inflow” is ~7,000 FTEs per annum • 22% of the workforce is female (28% in civil, 12% in defence) • 81% generic skills, 18% nuclear skills, 1% subject matter experts • 3300 trainees total in SLCs and Defence Enterprise (16% graduate trainees) • At peak demand on Civils Construction, over 4,000 workers will be required on each nuclear new build site • Manufacturing workforce is expected to rise from around 4,000 in 2014 to 8,500 at the peak of onsite activity in 2025

  12. Subject positioning in the BOD POD® only marginally affects measurement of body volume and estimation of percent body fat in young adult men.

    Directory of Open Access Journals (Sweden)

    Maarten W Peeters

    Full Text Available INTRODUCTION: The aim of the study was to evaluate whether subject positioning would affect the measurement of raw body volume, thoracic gas volume, corrected body volume and the resulting percent body fat as assessed by air displacement plethysmography (ADP. METHODS: Twenty-five young adult men (20.7±1.1 y, BMI = 22.5±1.4 kg/m(2 were measured using the BOD POD® system using a measured thoracic gas volume sitting in a 'forward bent' position and sitting up in a straight position in random order. RESULTS: Raw body volume was 58±124 ml (p<0.05 higher in the 'straight' position compared to the 'bent' position. The mean difference in measured thoracic gas volume (bent-straight = -71±211 ml was not statistically significant. Corrected body volume and percent body fat in the bent position consequently were on average 86±122 ml (p<0.05 and 0.5±0.7% (p<0.05 lower than in the straight position respectively. CONCLUSION: Although the differences reached statistical significance, absolute differences are rather small. Subject positioning should be viewed as a factor that may contribute to between-test variability and hence contribute to (inprecision in detecting small individual changes in body composition, rather than a potential source of systematic bias. It therefore may be advisable to pay attention to standardizing subject positioning when tracking small changes in PF are of interest. The cause of the differences is shown not to be related to changes in the volume of isothermal air in the lungs. It is hypothesized and calculated that the observed direction and magnitude of these differences may arise from the surface area artifact which does not take into account that a subject in the bent position exposes more skin to the air in the device therefore potentially creating a larger underestimation of the actual body volume due to the isothermal effect of air close to the skin.

  13. Demand Modelling in Telecommunications

    Directory of Open Access Journals (Sweden)

    M. Chvalina

    2009-01-01

    Full Text Available This article analyses the existing possibilities for using Standard Statistical Methods and Artificial Intelligence Methods for a short-term forecast and simulation of demand in the field of telecommunications. The most widespread methods are based on Time Series Analysis. Nowadays, approaches based on Artificial Intelligence Methods, including Neural Networks, are booming. Separate approaches will be used in the study of Demand Modelling in Telecommunications, and the results of these models will be compared with actual guaranteed values. Then we will examine the quality of Neural Network models. 

  14. DemandStat

    International Nuclear Information System (INIS)

    2003-01-01

    DemandStat is an accurate and up-to-date international statistics database dedicated to energy demand, with an unrivaled level of details for powerful market analysis. It provides detailed consumption statistics (30 sectors) on all energies, detailed 2003 data and historical annual data since 1970, frequent data revision and update (2 updates options), 150 data sources gathered and expertized, all data on a single database Consistent and homogeneous statistics, in line with all major data providers (IEA, Eurostat, ADB, OLADE, etc), no ruptures in time-series with easy request building and data analysis and reactive support from data experts. (A.L.B.)

  15. Education on Demand

    DEFF Research Database (Denmark)

    Boysen, Lis; Hende, Merete

    2015-01-01

    Dette notat beskriver nogle af resultaterne fra programmet "Education on Demand' i projektet Det erhvervsrettede Uddannelseslaboratorium. Programmet har haft fokus på udfordringer og forandringsbehov i uddannelsesinstitutioner og -systemet. Herunder har det beskæftiget sig særligt med de to temat......Dette notat beskriver nogle af resultaterne fra programmet "Education on Demand' i projektet Det erhvervsrettede Uddannelseslaboratorium. Programmet har haft fokus på udfordringer og forandringsbehov i uddannelsesinstitutioner og -systemet. Herunder har det beskæftiget sig særligt med de...

  16. Iron oxide minerals in dust-source sediments from the Bodélé Depression, Chad: Implications for radiative properties and Fe bioavailability of dust plumes from the Sahara

    Science.gov (United States)

    Moskowitz, Bruce M; Reynolds, Richard L.; Goldstein, Harland L.; Beroquo, Thelma; Kokaly, Raymond F.; Bristow, Charlie S

    2016-01-01

    Atmospheric mineral dust can influence climate and biogeochemical cycles. An important component of mineral dust is ferric oxide minerals (hematite and goethite) which have been shown to influence strongly the optical properties of dust plumes and thus affect the radiative forcing of global dust. Here we report on the iron mineralogy of dust-source samples from the Bodélé Depression (Chad, north-central Africa), which is estimated to be Earth’s most prolific dust producer and may be a key contributor to the global radiative budget of the atmosphere as well as to long-range nutrient transport to the Amazon Basin. By using a combination of magnetic property measurements, Mössbauer spectroscopy, reflectance spectroscopy, chemical analysis, and scanning electron microscopy, we document the abundance and relative amounts of goethite, hematite, and magnetite in dust-source samples from the Bodélé Depression. The partition between hematite and goethite is important to know to improve models for the radiative effects of ferric oxide minerals in mineral dust aerosols. The combination of methods shows (1) the dominance of goethite over hematite in the source sediments, (2) the abundance and occurrences of their nanosize components, and (3) the ubiquity of magnetite, albeit in small amounts. Dominant goethite and subordinate hematite together compose about 2% of yellow-reddish dust-source sediments from the Bodélé Depression and contribute strongly to diminution of reflectance in bulk samples. These observations imply that dust plumes from the Bodélé Depression that are derived from goethite-dominated sediments strongly absorb solar radiation. The presence of ubiquitous magnetite (0.002–0.57 wt%) is also noteworthy for its potentially higher solubility relative to ferric oxide and for its small sizes, including PM iron apportionment is estimated at about 33% in ferric oxide minerals, 1.4% in magnetite, and 65% in ferric silicates. Structural iron in clay

  17. RECENT PROGRESS OF OXYGEN/NITROGEN SEPARATION USING MEMBRANE TECHNOLOGY

    OpenAIRE

    K. C. CHONG; S. O. LAI; H. S. THIAM; H. C. TEOH; S. L. HENG

    2016-01-01

    The oxygen-enriched air is highly demanded for various industrial applications such as medical, chemical and enhanced combustion processes. The conventional oxygen/nitrogen production is either cryogenic distillation or pressure swing adsorption (PSA). Both of these techniques possess the production capability of 20 to 300 tonnes of oxygen per day and oxygen purity of more than 95%. However, these techniques are energy intensive. Alternatively, membrane technology is an emerging technology...

  18. Causality in demand

    DEFF Research Database (Denmark)

    Nielsen, Max; Jensen, Frank; Setälä, Jari

    2011-01-01

    to fish demand. On the German market for farmed trout and substitutes, it is found that supply sources, i.e. aquaculture and fishery, are not the only determinant of causality. Storing, tightness of management and aggregation level of integrated markets might also be important. The methodological...

  19. Oil supply and demand

    Energy Technology Data Exchange (ETDEWEB)

    Babusiaux, D

    2004-07-01

    Following the military intervention in Iraq, it is taking longer than expected for Iraqi exports to make a comeback on the market. Demand is sustained by economic growth in China and in the United States. OPEC is modulating production to prevent inventory build-up. Prices have stayed high despite increased production by non-OPEC countries, especially Russia. (author)

  20. Oil supply and demand

    Energy Technology Data Exchange (ETDEWEB)

    Rech, O

    2006-07-01

    The year 2004 saw a change in the oil market paradigm that was confirmed in 2005. Despite a calmer geopolitical context, prices continued to rise vigorously. Driven by world demand, they remain high as a result of the saturation of production and refining capacity. The market is still seeking its new equilibrium. (author)

  1. Oil supply and demand

    International Nuclear Information System (INIS)

    Rech, O.

    2006-01-01

    The year 2004 saw a change in the oil market paradigm that was confirmed in 2005. Despite a calmer geopolitical context, prices continued to rise vigorously. Driven by world demand, they remain high as a result of the saturation of production and refining capacity. The market is still seeking its new equilibrium. (author)

  2. The demand for euros

    NARCIS (Netherlands)

    Arnold, I.J.M.; Roelands, S.

    2010-01-01

    This paper investigates the demand for euros using panel data for 10 euro area countries covering the period from 1999 to 2008. Monetary aggregates are constructed to ensure that money is a national concept by excluding deposits owned by non-residents and including external deposits owned by

  3. Oil supply and demand

    International Nuclear Information System (INIS)

    Babusiaux, D.

    2004-01-01

    Following the military intervention in Iraq, it is taking longer than expected for Iraqi exports to make a comeback on the market. Demand is sustained by economic growth in China and in the United States. OPEC is modulating production to prevent inventory build-up. Prices have stayed high despite increased production by non-OPEC countries, especially Russia. (author)

  4. Oil supply and demand

    International Nuclear Information System (INIS)

    Rech, O.

    2004-01-01

    World oil demand, driven by economic development in China, posted the highest growth rate in 20 years. In a context of geopolitical uncertainty, prices are soaring, encouraged by low inventory and the low availability of residual production capacity. Will 2004 bring a change in the oil market paradigm? (author)

  5. Textbook Factor Demand Curves.

    Science.gov (United States)

    Davis, Joe C.

    1994-01-01

    Maintains that teachers and textbook graphics follow the same basic pattern in illustrating changes in demand curves when product prices increase. Asserts that the use of computer graphics will enable teachers to be more precise in their graphic presentation of price elasticity. (CFR)

  6. Oil supply and demand

    Energy Technology Data Exchange (ETDEWEB)

    Rech, O

    2004-07-01

    World oil demand, driven by economic development in China, posted the highest growth rate in 20 years. In a context of geopolitical uncertainty, prices are soaring, encouraged by low inventory and the low availability of residual production capacity. Will 2004 bring a change in the oil market paradigm? (author)

  7. Pulmonary hematological parameters, energetic flight demands and their correlation with oxygen diffusion capacity in the lungs Parámetros hematológicos pulmonares, demandas energéticas del vuelo y su correlación la capacidad de difusión de oxígeno en los pulmones

    Directory of Open Access Journals (Sweden)

    M CANALS

    2007-09-01

    Full Text Available Hematological parameters of birds and mammals seem to respond to environmental requirements, such as hypoxia at high altitude and the energetic demands of locomotion and flight. In this work we hypothesize that lung capillary hematocrit and red blood size may be influenced by the energetic requirements of flight. Also, we propose that hematological parameters should vary together with the morphological parameters that determine oxygen diffusion capacity. We analyzed the red blood cell size and the local characteristics of the pulmonary capillary hematocrit correlating these with the pulmonary factors that determines the oxygen diffusion capacity. We deal with seven species, non-flying and flying birds and mammals, with different energetic requirements. The capillary hematocrit was not different in each taxon, but the red blood cell size was smaller in flying mammals and birds than non-flying ones. Correlation of erythrocyte size with the diffusing characteristics of the lungs produced a non-phylogenetic clustering with a group constituting by the bats Tadarida brasiliensis y Myotis chiloensis, and the bird Z. auriculata; revealing similar functional response in unrelated species. Finally, in mammals, a negative correlation between the red blood cell size and the mass-specific oxygen diffusion capacity was obtained. These results suggest that the direction of the hematological and pulmonary adjustments is governed mainly by the requirements of flight independent of phylogenetic origin of the species studiedLos parámetros hematológicos y pulmonares parecen responder a las exigencias ambientales como la hipoxia y la alta altitud y a los requerimientos energéticos de la locomoción. En este trabajo sometemos a prueba la hipótesis que el hematocrito del capilar pulmonar y el tamaño del glóbulo rojo pueden ser influidos por los requerimientos energéticos del vuelo. También proponemos que los parámetros hematológicos varían en conjunto con

  8. Electricity demand in Tunisia

    International Nuclear Information System (INIS)

    Gam, Imen; Ben Rejeb, Jaleleddine

    2012-01-01

    This paper examines the global electricity demand in Tunisia as a function of gross domestic product in constant price, the degree of urbanization, the average annual temperature, and the real electricity price per Kwh. This demand will be examined employing annual data over a period spanning almost thirty one years from 1976 to 2006. A long run relationship between the variables under consideration is determined using the Vector Autoregressive Regression. The empirical results suggest that the electricity demand in Tunisia is sensitive to its past value, any changes in gross domestic product and electricity price. The electricity price effects have a negative impact on long-run electricity consumption. However, the gross domestic product and the past value of electricity consumption have a positive effect. Moreover, the causality test reveals a unidirectional relationship between price and electricity consumption. Our empirical findings are effective to policy makers to maintain the electricity consumption in Tunisia by using the appropriate strategy. - Highlights: ► This paper examined the electricity demand in Tunisia in the long-run. ► The empirical analysis revealed that in the long-run the electricity demand is affected by changes in its past value, GDP in constant price and real electricity price. ► There is a unidirectional relationship between price and electricity consumption, that is to say, that the electricity price causes the consumption. ► Those results suggest that a pricing policy can be an effective instrument to rationalize the electricity consumption in Tunisia in the long-run.

  9. Effect of hypolimnetic oxygenation on oxygen depletion rates in two water-supply reservoirs.

    Science.gov (United States)

    Gantzer, Paul A; Bryant, Lee D; Little, John C

    2009-04-01

    Oxygenation systems, such as bubble-plume diffusers, are used to improve water quality by replenishing dissolved oxygen (DO) in the hypolimnia of water-supply reservoirs. The diffusers induce circulation and mixing, which helps distribute DO throughout the hypolimnion. Mixing, however, has also been observed to increase hypolimnetic oxygen demand (HOD) during system operation, thus accelerating oxygen depletion. Two water-supply reservoirs (Spring Hollow Reservoir (SHR) and Carvins Cove Reservoir (CCR)) that employ linear bubble-plume diffusers were studied to quantify diffuser effects on HOD. A recently validated plume model was used to predict oxygen addition rates. The results were used together with observed oxygen accumulation rates to evaluate HOD over a wide range of applied gas flow rates. Plume-induced mixing correlated well with applied gas flow rate and was observed to increase HOD. Linear relationships between applied gas flow rate and HOD were found for both SHR and CCR. HOD was also observed to be independent of bulk hypolimnion oxygen concentration, indicating that HOD is controlled by induced mixing. Despite transient increases in HOD, oxygenation caused an overall decrease in background HOD, as well as a decrease in induced HOD during diffuser operation, over several years. This suggests that the residual or background oxygen demand decreases from one year to the next. Despite diffuser-induced increases in HOD, hypolimnetic oxygenation remains a viable method for replenishing DO in thermally-stratified water-supply reservoirs such as SHR and CCR.

  10. Aggregated Demand Modelling Including Distributed Generation, Storage and Demand Response

    OpenAIRE

    Marzooghi, Hesamoddin; Hill, David J.; Verbic, Gregor

    2014-01-01

    It is anticipated that penetration of renewable energy sources (RESs) in power systems will increase further in the next decades mainly due to environmental issues. In the long term of several decades, which we refer to in terms of the future grid (FG), balancing between supply and demand will become dependent on demand actions including demand response (DR) and energy storage. So far, FG feasibility studies have not considered these new demand-side developments for modelling future demand. I...

  11. Sulphur demand growing. [Alberta

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-20

    Sulfur markets look better going into 1975 than they have for several years, as North American demand growth is being filled largely by elemental sulfur producers and overseas. Demand is rising as fast as the capacity of Canadian transportation and handling facilities. It will take a long time to make much of a dent in the total Alberta stockpile of 14 million long tons at the end of 1974, with involuntary production from sour gas plants exceeding sales volume since 1972. However, there is some encouragement in the approaching peakout of production combined with a substantial increase in price since the low point of the cycle at the beginning of 1973, and a predicted rise of at least 20% in domestic (North American) sales this year over 1974.

  12. Ontario demand response scenarios

    International Nuclear Information System (INIS)

    Rowlands, I.H.

    2005-09-01

    Strategies for demand management in Ontario were examined via 2 scenarios for a commercial/institutional building with a normal summertime peak load of 300 kW between 14:00 and 18:00 during a period of high electricity demand and high electricity prices. The first scenario involved the deployment of a 150 kW on-site generator fuelled by either diesel or natural gas. The second scenario involved curtailing load by 60 kW during the same periods. Costs and benefits of both scenarios were evaluated for 3 groups: consumers, system operators and society. Benefits included electricity cost savings, deferred transmission capacity development, lower system prices for electricity, as well as environmental changes, economic development, and a greater sense of corporate social responsibility. It was noted that while significant benefits were observed for all 3 groups, they were not substantial enough to encourage action, as the savings arising from deferred generation capacity development do not accrue to individual players. The largest potential benefit was identified as lower prices, spread across all users of electricity in Ontario. It was recommended that representative bodies cooperate so that the system-wide benefits can be reaped. It was noted that if 10 municipal utilities were able to have 250 commercial or institutional customers engaged in distributed response, then a total peak demand reduction of 375 MW could be achieved, representing more than 25 per cent of Ontario's target for energy conservation. It was concluded that demand response often involves the investment of capital and new on-site procedures, which may affect reactions to various incentives. 78 refs., 10 tabs., 5 figs

  13. Household electricity demand profiles

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Heiselberg, Per Kvols; Larsen, Olena Kalyanova

    2016-01-01

    Highlights •A 1-min resolution household electricity load model is presented. •Model adapts a bottom-up approach with single appliance as the main building block. •Load profiles are used to analyse the flexibility potential of household appliances. •Load profiles can be applied in other domains, .......g. building energy simulations. •The demand level of houses with different number of occupants is well captured....

  14. Energy demand patterns

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, L; Schipper, L; Meyers, S; Sathaye, J; Hara, Y

    1984-05-01

    This report brings together three papers on energy demand presented at the Energy Research Priorities Seminar held in Ottawa on 8-10 August 1983. The first paper suggests a framework in which energy demand studies may be organized if they are to be useful in policy-making. Disaggregation and the analysis of the chain of energy transformations are possible paths toward more stable and reliable parameters. The second paper points to another factor that leads to instability in sectoral parameters, namely a changeover from one technology to another; insofar as technologies producing a product (or service) vary in their energy intensity, a technological shift will also change the energy intensity of the product. Rapid technological change is characteristic of some sectors in developing countries, and may well account for the high aggregate GDP-elasticities of energy consumption observed. The third paper begins with estimates of these elasticities, which were greater than one for all the member countries of the Asian Development Bank in 1961-78. The high elasticities, together with extreme oil dependence, made them vulnerable to the drastic rise in the oil price after 1973. The author distinguishes three diverging patterns of national experience. The oil-surplus countries naturally gained from the rise in the oil price. Among oil-deficit countries, the newly industrialized countries expanded their exports so rapidly that the oil crisis no longer worried them. For the rest, balance of payments adjustments became a prime concern of policy. Whether they dealt with the oil bill by borrowing, by import substitution, or by demand restraint, the impact of energy on their growth was unmistakable. The paper also shows why energy-demand studies, and energy studies in general, deserve to be taken seriously. 16 refs., 4 figs., 18 tabs.

  15. Migration and Tourism Demand

    Directory of Open Access Journals (Sweden)

    Nuno Carlos LEITÃO

    2012-02-01

    Full Text Available This study considers the relationship between immigration and Portuguese tourism demand for the period 1995-2008, using a dynamic panel data approach. The findings indicate that Portuguese tourism increased significantly during the period in accordance with the values expected for a developed country. The regression results show that income, shock of immigration, population, and geographical distance between Portugal and countries of origin are the main determinants of Portuguese tourism.

  16. Demand scenarios, worldwide

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, A [Massachusetts Inst. of Technology, Center for Technology, Policy and Industrial Development and the MIT Joint Program on the Science and Policy of Global Change, Cambridge, MA (United States)

    1996-11-01

    Existing methods are inadequate for developing aggregate (regional and global) and long-term (several decades) passenger transport demand scenarios, since they are mainly based on simple extensions of current patterns rather than causal relationships that account for the competition among transport modes (aircraft, automobiles, buses and trains) to provide transport services. The demand scenario presented in this paper is based on two empirically proven invariances of human behavior. First, transport accounts for 10 to 15 percent of household total expenditures for those owning an automobile, and around 5 percent for non-motorized households on average (travel money budget). Second, the mean time spent traveling is approximately one hour per capita per day (travel time budget). These two budgets constraints determine the dynamics of the scenario: rising income increases per capita expenditure on travel which, in turn, increase demand for mobility. Limited travel time constraints travelers to shift to faster transport systems. The scenario is initiated with the first integrated historical data set on traffic volume in 11 world regions and the globe from 1960 to 1990 for all major modes of motorized transport. World average per capita traffic volume, which was 1,800 kilometers in 1960 and 4,2090 in 1990, is estimated to rise to 7,900 kilometers in 2020 - given a modest average increase in Gross World Product of 1.9% per year. Higher economic growth rates in Asian regions result in an increase in regional per capita traffic volume up to a factor of 5.3 from 1990 levels. Modal splits continue shifting to more flexible and faster modes of transport. At one point, passenger cars can no longer satisfy the increasing demand for speed (i.e. rising mobility within a fixed time budget). In North America it is estimated that the absolute traffic volume of automobiles will gradually decline starting in the 2010s. (author) 13 figs., 6 tabs., 35 refs.

  17. Supply and demand perspectives

    International Nuclear Information System (INIS)

    Trienekens, Pieter

    1999-01-01

    The outlook for the European gas market is one of steady growth. This growth will manifest itself in all regions and in all sectors of the market, but most strongly in the power generating sector. To meet future demand, it is necessary to bring gas to Western Europe from remote sources in Russia, North Africa and Norway. These new gas supplies require heavy investments in production and transportation, which can only be undertaken on the basis of long-term take-or-pay contracts. Famous examples of such contracts are the development of the Troll field, the Yamal-Europe pipeline connection, and the bringing on stream of Nigerian LNG for Europe. Tensions are likely to arise between the nature of these long-term gas contracts and the dynamic nature of demand in the gas market, and more specifically in the main growth market, the power sector. The presentation further elaborates on the tensions underlying supply and demand in the years to come

  18. Four-Hour Dives with Exercise While Breathing Oxygen Partial Pressure of 1.3 ATM

    National Research Council Canada - National Science Library

    Shykoff, B

    2006-01-01

    .... Still, because the increased ventilatory demands and blood flow to the lungs during underwater exercise may cause pulmonary injury or may increase oxygen-induced injury over those ventilatory demands...

  19. Meeting increased demand.

    Science.gov (United States)

    Blair, Andrew

    2004-07-01

    New Zealand is a little country with a little economy but with a population that's rapidly aging. New Zealand's population is only 4.3 million people. It's GDP is only $US58.6 billion (2002). New Zealand's expenditure on health as a percentage of GDP is not out of line with that of other countries. As a nation we have been increasing expenditure on health over recent years. In 1990 we spent 7% of GDP on health. In 1995 that increased to 7.65% and is now 8.3%. However, in per capita terms our expenditure on health does not compare so well with like countries. The size of New Zealand's economy is restricting what our country spends on health. Health is already the second highest demand on the New Zealand tax dollar. The tolerance of New Zealanders would be challenged if a Government attempted to increase taxes further to meet the growing demands for expenditure on health, but at the same time the population's expectations are increasing. This is the challenging situation we face today. What lies ahead? Like all industrialized countries New Zealand is facing an aging population. The population below age 40 is decreasing, but it is increasing significantly over that age. 16% of the population is currently aged over 60. By 2051 this proportion will almost double to just over 31%. Coupled with the aging population is increased awareness and expectations, as access to options for treatment and technology becomes readily accessible to the population through such media as the internet. The extent of the impact of the aging population can be clearly represented by focusing on one specialty such as orthopaedics. The New Zealand Orthopaecic Association undertook a study in July 2003 which concluded (among other things) that as a result of the projected aging of the population, over the next 50 years: Musculo-skeletal operations will increase by over 30%. The number of hip replacements will nearly double. The incidence of osteoporosis will increase by a massive 201%. The number

  20. Physiological demands of downhill mountain biking.

    Science.gov (United States)

    Burr, Jamie F; Drury, C Taylor; Ivey, Adam C; Warburton, Darren E R

    2012-12-01

    Mountain biking is a popular recreational pursuit and the physiological demands of cross-country style riding have been well documented. However, little is known regarding the growing discipline of gravity-assisted downhill cycling. We characterised the physiological demands of downhill mountain biking under typical riding conditions. Riding oxygen consumption (VO(2)) and heart rate (HR) were measured on 11 male and eight female experienced downhill cyclists and compared with data during a standardised incremental to maximum (VO(2max)) exercise test. The mean VO(2) while riding was 23.1 ± 6.9 ml · kg(-1) · min(-1) or 52 ± 14% of VO(2max) with corresponding heart rates of 146 ± 11 bpm (80 ± 6% HRmax). Over 65% of the ride was in a zone at or above an intensity level associated with improvements in health-related fitness. However, the participants' heart rates and ratings of perceived exertion were artificially inflated in comparison with the actual metabolic demands of the downhill ride. Substantial muscular fatigue was evident in grip strength, which decreased 5.4 ± 9.4 kg (5.5 ± 11.2%, P = 0.03) post-ride. Participation in downhill mountain biking is associated with significant physiological demands, which are in a range associated with beneficial effects on health-related fitness.

  1. Psychopathology and tobacco demand.

    Science.gov (United States)

    Farris, Samantha G; Aston, Elizabeth R; Zvolensky, Michael J; Abrantes, Ana M; Metrik, Jane

    2017-08-01

    Behavioral economic measurement of the relative value of tobacco (Cigarette Purchase Task; CPT) is used to examine individual differences in motivation for tobacco under certain contexts. Smokers with psychopathology, relative to those without, may demonstrate stronger demand for tobacco following a period of smoking deprivation, which could account for disparate rates of smoking and cessation among this subgroup. Participants (n=111) were community-recruited adult daily smokers who completed the CPT after a deprivation period of approximately 60min. Presence of psychopathology was assessed via clinical interview; 40.5% (n=45) of the sample met criteria for past-year psychological diagnosis. Specifically, 31.5% (n=35) had an emotional disorder (anxiety/depressive disorder), 17.1% (n=19) had a substance use disorder, and 19.1% of the sample had more than one disorder. Smokers with any psychopathology showed significantly higher intensity (demand at unrestricted cost; $0) and O max (peak expenditure for a drug) relative to smokers with no psychopathology. Intensity was significantly higher among smokers with an emotional disorder compared to those without. Smokers with a substance use disorder showed significantly higher intensity and O max , and lower elasticity, reflecting greater insensitivity to price increases. Having≥2 disorders was associated with higher intensity relative to having 1 or no disorders. Findings suggest that presence of psychopathology may be associated with greater and more persistent motivation to smoke. Future work is needed to explore the mechanism linking psychopathology to tobacco demand. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Ethane supply and demand

    International Nuclear Information System (INIS)

    Jamerson, J.B.

    1993-01-01

    Estimates are given for ethane production, chiefly from the Gulf Coast area. Increase in interregional transfers are predicted. Comparisons from 1992 through 1995 are made. The author concludes the following: ethane will be supply limited over the decade of the 90's; values will be over competing feedstocks; minimum practical demands will be close to available supply; regional relationships will reflect pipeline tariffs; purity ethane/EP spreads may narrow with new Mt. Belvieu fractionation capacity; new domestic supplies will back out imports; and Ethane's share of ethylene production may drop over the period

  3. Road infrastructure and demand induction

    DEFF Research Database (Denmark)

    Nielsen, Thomas Alexander Sick; Hovgesen, Henrik Harder; Lahrmann, Harry

    2006-01-01

    a long screenline is used to measure the development in aggregate demand in selected corridors. The paper analyses demand induction by establishing time series of aggregate demand that is compared with the national traffic index. Significant trend breaks in the association between aggregate demand...... in the corridors and the national index, following the opening of motorways or bridges, indicates demand induction by infrastructure expansion in a number of instances. Lack of significant trend breaks following opening year is found in peripheral areas where major population centres are missing. This indicates...... the necessity of some latent demand within suitable travel range for new infrastructure elements to produce significant amounts of induced demand. Estimates of demand induction as a percentage of the realised demand five years after opening are between 10% and 67% for new motorway sections depending...

  4. an improved solution of first order kinetics for biochemical oxygen ...

    African Journals Online (AJOL)

    DELL

    Accuracies of these methods were evaluated using relative error, Akaike ... Keywords: Wastewater, Environmental Engineering, Biochemical Oxygen Demand Kinetic Parameters,. Statistical ... evaluating organic pollution level and quality of wastewaters. ... compounds ...... method can be applied on electronic devices, and.

  5. Demand response in energy markets

    International Nuclear Information System (INIS)

    Skytte, K.; Birk Mortensen, J.

    2004-11-01

    Improving the ability of energy demand to respond to wholesale prices during critical periods of the spot market can reduce the total costs of reliably meeting demand, and the level and volatility of the prices. This fact has lead to a growing interest in the short-run demand response. There has especially been a growing interest in the electricity market where peak-load periods with high spot prices and occasional local blackouts have recently been seen. Market concentration at the supply side can result in even higher peak-load prices. Demand response by shifting demand from peak to base-load periods can counteract the market power in the peak-load. However, demand response has so far been modest since the current short-term price elasticity seems to be small. This is also the case for related markets, for example, green certificates where the demand is determined as a percentage of the power demand, or for heat and natural gas markets. This raises a number of interesting research issues: 1) Demand response in different energy markets, 2) Estimation of price elasticity and flexibility, 3) Stimulation of demand response, 4) Regulation, policy and modelling aspects, 5) Demand response and market power at the supply side, 6) Energy security of supply, 7) Demand response in forward, spot, ancillary service, balance and capacity markets, 8) Demand response in deviated markets, e.g., emission, futures, and green certificate markets, 9) Value of increased demand response, 10) Flexible households. (BA)

  6. Soil aquifer treatment of artificial wastewater under saturated conditions

    KAUST Repository

    Essandoh, H. M K; Tizaoui, Chedly; Mohamed, Mostafa H A; Amy, Gary L.; Brdjanovic, Damir

    2011-01-01

    A 2000 mm long saturated laboratory soil column was used to simulate soil aquifer treatment under saturated conditions to assess the removal of chemical and biochemical oxygen demand (COD and BOD), dissolved organic carbon (DOC), nitrogen

  7. Demand for electrical energy

    International Nuclear Information System (INIS)

    Bergougnoux, J.; Fouquet, D.

    1983-01-01

    The different utilizations of electric energy are reviewed in the residential and tertiary sectors, in the industry. The competitive position of electricity in regard to other fuels has been strengthned by the sudden rise in the price of oil in 1973-1974 and 1979-1980. The evolution of electricity prices depended on the steps taken to adjust the electricity generation system. The substitution of electricity applications for hydro-carbons is an essential point of energy policy. The adjustment at all times, at least cost and most reliability, of the supply of electricity to the demand for it is a major problem in the design and operation of electric systems. National demand for power at a given moment is extremely diversified. Electricity consumption presents daily and seasonal variations, and variations according to the different sectors. Forecasting power requirements is for any decision on operation or investment relating to an electrical system. Load management is desirable (prices according to the customers, optional tariffs for ''peak-day withdrawal''). To conclude, prospects for increased electricity consumption are discussed [fr

  8. Demand for male contraception.

    Science.gov (United States)

    Dorman, Emily; Bishai, David

    2012-10-01

    The biological basis for male contraception was established decades ago, but despite promising breakthroughs and the financial burden men increasingly bear due to better enforcement of child support policies, no viable alternative to the condom has been brought to market. Men who wish to control their fertility must rely on female compliance with contraceptives, barrier methods, vasectomy or abstinence. Over the last 10 years, the pharmaceutical industry has abandoned most of its investment in the field, leaving only nonprofit organisations and public entities pursuing male contraception. Leading explanations are uncertain forecasts of market demand pitted against the need for critical investments to demonstrate the safety of existing candidate products. This paper explores the developments and challenges in male contraception research. We produce preliminary estimates of potential market size for a safe and effective male contraceptive based on available data to estimate the potential market for a novel male method.

  9. Animating the Ethical Demand

    DEFF Research Database (Denmark)

    Vistisen, Peter; Jensen, Thessa; Poulsen, Søren Bolvig

    2015-01-01

    This paper addresses the challenge of attaining ethical user stances during the design process of products and services and proposes animation-based sketching as a design method, which supports elaborating and examining different ethical stances towards the user. The discussion is qualified...... by an empirical study of Responsible Research and Innovation (RRI) in a Triple Helix constellation. Using a three-week long innovation workshop, U- CrAc, involving 16 Danish companies and organisations and 142 students as empirical data, we discuss how animation-based sketching can explore not yet existing user...... dispositions, as well as create an incentive for ethical conduct in development and innovation processes. The ethical fulcrum evolves around Løgstrup’s Ethical Demand and his notion of spontaneous life manifestations. From this, three ethical stances are developed; apathy, sympathy and empathy. By exploring...

  10. Rewarding yet demanding

    DEFF Research Database (Denmark)

    Bjørkedal, S T B; Torsting, A M B; Møller, T

    2016-01-01

    in a logbook. The Canadian Occupational Performance Measure was used to initiate and guide the intervention and the Canadian Model of Client-Centred Enablement for the client-therapist relationship. RESULTS: Participants described the intervention, which presupposed a certain level of patient readiness...... design comprising an eight-week client-centred occupational therapy intervention with semi-structured interviews with five of the six clients out of 10 who completed the intervention. Braun and Clark's thematic analysis was applied to the transcripts. Adherence rate and dropouts were recorded......, as demanding. Participants valued engaging in real-life occupations while anchoring new strategies but also the occupational therapist's role in dealing with failure. Participants felt the intervention assisted in their recovery process and enabled them to engage in meaningful occupations. CONCLUSION...

  11. PROOF on Demand

    International Nuclear Information System (INIS)

    Malzacher, Peter; Manafov, Anar

    2010-01-01

    PROOF on Demand (PoD) is a set of utilities, which allows starting a PROOF cluster at user request, on any resource management system. It provides a plug-in based system, which allows to use different job submission frontends, such as LSF or gLite WMS. Main components of PoD are the PROOFAgent and the PAConsole. PROOFAgent provides the communication layer between the PROOF master on the local machine and the PROOF workers on the remote resources, possibly behind a firewall. PAConsole provides a user-friendly GUI, which is used to setup, manage, and shutdown the dynamic PROOF cluster. Installation is simple and doesn't require administrator privileges, and all the processes run in user space. PoD gives users, who don't have a centrally-administrated static PROOF cluster at their institute, the possibility to enjoy the full power of interactive analysis with PROOF.

  12. Artificial oxygen transport protein

    Science.gov (United States)

    Dutton, P. Leslie

    2014-09-30

    This invention provides heme-containing peptides capable of binding molecular oxygen at room temperature. These compounds may be useful in the absorption of molecular oxygen from molecular oxygen-containing atmospheres. Also included in the invention are methods for treating an oxygen transport deficiency in a mammal.

  13. Environment-quality demands

    International Nuclear Information System (INIS)

    Delfini, M.G.; Leenhouts, H.P.

    1988-12-01

    In the framework of the Environment Quality Requirements (MKE) project a model has been designed in which environment-quality demands have been defined and quantified, and a measuring strategy has been developed. In the model it is required for the quality of the environment that the radionuclide concentration in the various environment compartiments remains limited in order to keep the effective dose equivalence for the 'reference man' under a certain reference level. In order to be able to determine the maximum nuclide concentration it is necessary to quantify the relation between the concentration in the environment and the dose for the people. The quantitative relation between concentration and dose has been established on the base of parameters (Derived Activity Limits (DAL's) which have to be calculated for each environment compartiment, each nuclide and each exposure pathway. This model has been described and, as example, the DAL's have been calculated for the compartiment air (for which the two exposure pathways inhalation and direct radiation were considered). For the other environment compartiments a similar elaboration is needed. The feasibility of application of the MKE-model in the actual practice of measurements in the environment and examination of dose for the population depends upon the possibility for performing nuclide specific measurements in all environment compartiments, the level of the dose resulting from the contamination of the environment and the related accurateness of the measurements

  14. Modelling Commodity Demands and Labour Supply with m-Demands

    OpenAIRE

    Browning, Martin

    1999-01-01

    In the empirical modelling of demands and labour supply we often lack data on a full set of goods. The usual response is to invoke separability assumptions. Here we present an alternative based on modelling demands as a function of prices and the quantity of a reference good rather than total expenditure. We term such demands m-demands. The advantage of this approach is that we make maximum use of the data to hand without invoking implausible separability assumptions. In the theory section qu...

  15. Oxygen supply in aquatic ectotherms: partial pressure and solubility together explain biodiversity and size patterns.

    Science.gov (United States)

    Verberk, Wilco C E P; Bilton, David T; Calosi, Piero; Spicer, John I

    2011-08-01

    Aquatic ectotherms face the continuous challenge of capturing sufficient oxygen from their environment as the diffusion rate of oxygen in water is 3 x 10(5) times lower than in air. Despite the recognized importance of oxygen in shaping aquatic communities, consensus on what drives environmental oxygen availability is lacking. Physiologists emphasize oxygen partial pressure, while ecologists emphasize oxygen solubility, traditionally expressing oxygen in terms of concentrations. To resolve the question of whether partial pressure or solubility limits oxygen supply in nature, we return to first principles and derive an index of oxygen supply from Fick's classic first law of diffusion. This oxygen supply index (OSI) incorporates both partial pressure and solubility. Our OSI successfully explains published patterns in body size and species across environmental clines linked to differences in oxygen partial pressure (altitude, organic pollution) or oxygen solubility (temperature and salinity). Moreover, the OSI was more accurately and consistently related to these ecological patterns than other measures of oxygen (oxygen saturation, dissolved oxygen concentration, biochemical oxygen demand concentrations) and similarly outperformed temperature and altitude, which covaried with these environmental clines. Intriguingly, by incorporating gas diffusion rates, it becomes clear that actually more oxygen is available to an organism in warmer habitats where lower oxygen concentrations would suggest the reverse. Under our model, the observed reductions in aerobic performance in warmer habitats do not arise from lower oxygen concentrations, but instead through organismal oxygen demand exceeding supply. This reappraisal of how organismal thermal physiology and oxygen demands together shape aerobic performance in aquatic ectotherms and the new insight of how these components change with temperature have broad implications for predicting the responses of aquatic communities to

  16. Global energy demand outlook

    International Nuclear Information System (INIS)

    Hatcher, S.R.

    1999-01-01

    Perhaps the most compelling issue the world will face in the next century is the quality of life of the increasing populations of the poorer regions of the world. Energy is the key to generating wealth and protecting the environment. Today, most of the energy generated comes from fossil fuels and there should be enough for an increase in consumption over the next half century. However, this is likely to be impacted by the Kyoto Protocol on carbon dioxide emissions. Various authoritative studies lead to a global energy demand projection of between 850 to 1070 EJ per year in the mid-21 st century, which is nearly three times as much as the world uses today. The studies further indicate that, unless there is a major thrust by governments to create incentives and/or to levy heavy taxes, the use of fossil fuels will continue to increase and there will be a major increase in carbon dioxide emissions globally. Most of the increase will come from the newly industrializing countries which do not have the technology or financial resources to install non-carbon energy sources such as nuclear power, and the new renewable energy technologies. The real issue for the nuclear industry is investment cost. Developing countries, in particular will have difficulty in raising capital for energy projects with a high installed cost and will have difficulties in raising large blocks of capital. A reduction in investment costs of the order of 50% with a short construction schedule is in order if nuclear power is to compete and contribute significantly to energy supply and the reduction of carbon dioxide emissions. Current nuclear power plants and methods are simply not suited to the production of plants that will compete in this situation. Mass production designs are needed to get the benefits of cost reduction. Water cooled reactors are well demonstrated and positioned to achieve the cost reduction necessary but only via some radical thinking on the part of the designers. The reactors of

  17. Promotion and Fast Food Demand

    OpenAIRE

    Timothy J. Richards; Luis Padilla

    2009-01-01

    Many believe that fast food promotion is a significant cause of the obesity epidemic in North America. Industry members argue that promotion only reallocates brand shares and does not increase overall demand. We study the effect of fast food promotion on market share and total demand by estimating a discrete / continuous model of fast food restaurant choice and food expenditure that explicitly accounts for both spatial and temporal determinants of demand. Estimates are obtained using a unique...

  18. Intercity Travel Demand Analysis Model

    OpenAIRE

    Ming Lu; Hai Zhu; Xia Luo; Lei Lei

    2014-01-01

    It is well known that intercity travel is an important component of travel demand which belongs to short distance corridor travel. The conventional four-step method is no longer suitable for short distance corridor travel demand analysis for the time spent on urban traffic has a great impact on traveler's main mode choice. To solve this problem, the author studied the existing intercity travel demand analysis model, then improved it based on the study, and finally established a combined model...

  19. Job demands-resources model

    OpenAIRE

    Bakker, Arnold; Demerouti, Eva

    2013-01-01

    markdownabstract* The question of what causes job stress and what motivates people has received a lot of research attention during the past five decades. In this paper, we discuss Job Demands-Resources (JD-R) theory, which represents an extension of the Job Demands-Resources model (Bakker & Demerouti, 2007; Demerouti, Bakker, Nachreiner, & Schaufeli, 2001) and is inspired by job design and job stress theories. JD-R theory explains how job demands and resources have unique and multiplicative e...

  20. North American oil demand outlook

    International Nuclear Information System (INIS)

    Stewart, M.B.

    1995-01-01

    An understanding of the relationship of economic growth and potential petroleum product demand is needed to forecast the potential for North American oil demand growth as well as knowledge of world supply and price. The bullish expectations for economic growth in the US and Canada auger well for North American refiners and marketeers. The growth in world economic output forecast, however, means a larger oil demand and an increase in OPEC's pricing power. Such price increases could depress North American oil demand growth. (author)

  1. Theory and development of fluorescence-based optochemical oxygen sensors: oxygen optodes.

    Science.gov (United States)

    Opitz, N; Lübbers, D W

    1987-01-01

    As the preceding considerations concerning the physical and technical features of oxygen optodes have demonstrated, fluorescence-based optochemical oxygen sensors possess certain advantages and peculiarities compared to conventionally applied electrochemical sensors such as polarographic oxygen electrodes. First, in contrast to oxygen electrodes, oxygen measurements with oxygen optodes do not suffer from distortions caused by the reference electrodes. In addition, because of the polarographic process, platinum electrodes continuously consume oxygen, which falsifies the results, especially when small sample volumes or long-term measurements, or both, are involved, whereas the sensor layer of oxygen optodes must only be equilibrated. Moreover, the surface of the platinum wire has to be catalytically clean in order to obtain a plateau of the polarogram and, consequently, to achieve a low rest current at zero PO2. Unfortunately, the demand for catalytically clean platinum surfaces turns out to be rather critical, since surface contamination occurs even with membranized electrodes, resulting in the well-known phenomenon of "electrode poisoning." The question of the specificity of oxygen electrodes also must be considered. In this context, CO2 and halothane may interfere with oxygen measurements, whereas fluorescence quenching is unaffected by CO2 and halothane affects the measurements only slightly, depending on the special indicator used. Furthermore, because of the flow dependence, oxygen measurements with the oxygen electrode show a distinct "stirring effect" caused by the turbulence in front of the electrode, which disturbs the diffusion field. Because of the completely different physical principle of fluorescence optical sensors, such influences are not observed with oxygen optodes. In addition, isolation and shielding of electrical circuits found in electrodes are not necessary for optodes. Furthermore, the sensitivity of oxygen optodes can be tuned to the desired

  2. Biogeochemistry: Oxygen burrowed away

    NARCIS (Netherlands)

    Meysman, F.J.R.

    2014-01-01

    Multicellular animals probably evolved at the seafloor after a rise in oceanic oxygen levels. Biogeochemical model simulations suggest that as these animals started to rework the seafloor, they triggered a negative feedback that reduced global oxygen.

  3. Oxygen transport membrane

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof.......The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-12-31

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-12-31

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

  6. Proterozoic atmospheric oxygen

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene

    2014-01-01

    This article is concerned with the evolution of atmospheric oxygen concentrations through the Proterozoic Eon. In particular, this article will seek to place the history of atmospheric oxygenation through the Proterozoic Eon in the context of the evolving physical environment including the history...... of continental growth and volcanic outgassing, as well as biogeochemical processing of elements within the oceans. The author will seek to explore constraints on the history of oxygenation and understand which processes have regulated oxygen through this eon....

  7. Oxygen evolution reaction catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Haber, Joel A.; Jin, Jian; Xiang, Chengxiang; Gregoire, John M.; Jones, Ryan J.; Guevarra, Dan W.; Shinde, Aniketa A.

    2016-09-06

    An Oxygen Evolution Reaction (OER) catalyst includes a metal oxide that includes oxygen, cerium, and one or more second metals. In some instances, the cerium is 10 to 80 molar % of the metals in the metal oxide and/or the catalyst includes two or more second metals. The OER catalyst can be included in or on an electrode. The electrode can be arranged in an oxygen evolution system such that the Oxygen Evolution Reaction occurs at the electrode.

  8. Harnessing the power of demand

    Energy Technology Data Exchange (ETDEWEB)

    Sheffrin, Anjali; Yoshimura, Henry; LaPlante, David; Neenan, Bernard

    2008-03-15

    Demand response can provide a series of economic services to the market and also provide ''insurance value'' under low-likelihood, but high-impact circumstances in which grid reliablity is enhanced. Here is how ISOs and RTOs are fostering demand response within wholesale electricity markets. (author)

  9. Guidelines for forecasting energy demand

    International Nuclear Information System (INIS)

    Sonino, T.

    1976-11-01

    Four methodologies for forecasting energy demand are reviewed here after considering the role of energy in the economy and the analysis of energy use in different economic sectors. The special case of Israel is considered throughout, and some forecasts for energy demands in the year 2000 are presented. An energy supply mix that may be considered feasible is proposed. (author)

  10. Coal background paper. Coal demand

    International Nuclear Information System (INIS)

    1997-01-01

    Statistical data are presented on coal demands in IEA and OECD member countries and in other countries. Coal coaking and coaking coal consumption data are tabulated, and IEA secretariat's coal demand projections are summarized. Coal supply and production data by countries are given. Finally, coal trade data are presented, broken down for hard coal, steam coal, coking coal (imports and export). (R.P.)

  11. Uranium resources, demand and production

    International Nuclear Information System (INIS)

    Stipanicic, P.N.

    1985-05-01

    Estimations of the demand and production of principal uranium resource categories are presented. The estimations based on data analysis made by a joint 'NEA/IAEA Working Party on Uranium Resources' and the corresponding results are published by the OECD (Organization for Economic Co-operation and Development) in the 'Uranium Resources, Production and Demand' Known as 'Red Book'. (M.C.K.) [pt

  12. Demand differentiation in inventory systems

    NARCIS (Netherlands)

    Kleijn, M.J.

    1998-01-01

    This book deals with inventory systems where customer demand is categorised into different classes. Most inventory systems do not take into account individual customer preferences for a given product, and therefore handle all demand in a similar way. Nowadays, market segmentation has become a

  13. Demand Response in Smart Grids

    DEFF Research Database (Denmark)

    Hansen, Jacob; Knudsen, Jesper Viese; Annaswamy, Anuradha M.

    2014-01-01

    In recent decades, moves toward higher integration of Renewable Energy Resources have called for fundamental changes in both the planning and operation of the overall power grid. One such change is the incorporation of Demand Response (DR), the process by which consumers can adjust their demand...

  14. Credit demand in Mozambican manufacturing

    DEFF Research Database (Denmark)

    Byiers, Bruce; Rand, John; Tarp, Finn

    2010-01-01

    This paper uses two industrial firm surveys to identify the key determinants of credit demand in Mozambican manufacturing. We construct five different measures of being credit constrained and estimate desired debt demand. Besides firm size and ownership structure, we find evidence that general...

  15. Job demands-resources model

    NARCIS (Netherlands)

    A.B. Bakker (Arnold); E. Demerouti (Eva)

    2013-01-01

    markdownabstract* The question of what causes job stress and what motivates people has received a lot of research attention during the past five decades. In this paper, we discuss Job Demands-Resources (JD-R) theory, which represents an extension of the Job Demands-Resources model (Bakker &

  16. Residential energy demand in Brazil

    International Nuclear Information System (INIS)

    Arouca, M.; Gomes, F.M.; Rosa, L.P.

    1981-01-01

    The energy demand in Brazilian residential sector is studied, discussing the methodology for analyzing this demand from some ideas suggested, for developing an adequate method to brazilian characteristics. The residential energy consumption of several fuels in Brazil is also presented, including a comparative evaluation with the United States and France. (author)

  17. Demand as Frequency Controlled Reserve

    DEFF Research Database (Denmark)

    Xu, Zhao; Togeby, Mikael; Østergaard, Jacob

    This report summaries the research outcomes of the project ‘Demand as Frequency Controlled Reserve (DFR)’, which has received the support from Energinet.dk’s PSO program, Grant no. 2005-2-6380. The objective of this project is to investigate the technology of using electricity demands for providing...

  18. Aircraft Oxygen Generation

    Science.gov (United States)

    2012-02-01

    An Oxygen Enriched Air System for the AV-8A Harrier (NADC-81198-60).” 70 Horch , T., et. al. “The F-16 Onboard Oxygen Generating System: Performance...Only and Safety Privileged). Horch , T., Miller, R., Bomar, J., Tedor, J., Holden, R., Ikels, K., & Lozano, P. (1983). The F-16 Onboard Oxygen

  19. Evaluation of organic matter concentration in winery wastewater: a case study from Australia.

    Science.gov (United States)

    Quayle, Wendy C; Fattore, Alison; Zandona, Roy; Christen, Evan W; Arienzo, Michele

    2009-01-01

    The 5-day biological oxygen demand (BOD(5)) remains a key indicator for proof of compliance with environmental regulators in the monitoring and management of winery effluent. Inter-conversion factors from alternative tests that are more rapid, accurate and simpler to perform have been determined that allow prediction of BOD(5) in winery wastewaters, generally, and at different stages of production and treatment. Mean values obtained from this dataset offer rule of thumb inter-conversion factors: BOD(5) = 0.7 Chemical Oxygen Demand (COD), BOD(5) = 2.3 Total Organic Carbon (TOC) and BOD(5) = 2.7 Dissolved Organic Carbon (DOC). Specific predictive linear relationships are also provided. Out of the relationships between BOD(5) vs COD, TOC and DOC, in winery wastewater, irrespective of vintage or non-vintage production periods and stage of treatment, TOC offered the most reliable prediction of BOD(5). Ethanol, glucose and fructose were evaluated in untreated wastewater as predictors of BOD(5) due to their high specificity in winery effluent. A significant relationship was determined between BOD(5) and (ethanol + glucose + fructose; R(2) = 0.64, n = 19; pwinery effluents when using a commercially available mercury free test kit compared with using a traditional COD test kit that contained mercury. This suggests that mercury free COD test kits could be used by the wine industry for organic pollution assessment with associated reductions to user and environmental risk, as well as reducing the costs of kit waste disposal.

  20. Are demand forecasting techniques applicable to libraries?

    OpenAIRE

    Sridhar, M. S.

    1984-01-01

    Examines the nature and limitations of demand forecasting, discuses plausible methods of forecasting demand for information, suggests some useful hints for demand forecasting and concludes by emphasizing unified approach to demand forecasting.

  1. Oxygen configurations in silica

    International Nuclear Information System (INIS)

    Chelikowsky, James R.; Chadi, D. J.; Binggeli, N.

    2000-01-01

    We propose a transition state for oxygen in silica. This state is produced by the insertion of an oxygen molecule into the Si-O-Si bond, i.e., it consists of producing a Si-O-O-O-Si bond. This state allows molecular oxygen diffusion in silica without breaking the molecular O 2 bond and it is energetically more stable than a peroxy configuration. This configuration may allow for exchange of molecular oxygen with the oxygen in the silica framework. (c) 2000 The American Physical Society

  2. A theoretical model for the effects of reduced hemoglobin-oxygen affinity on tumor oxygenation

    International Nuclear Information System (INIS)

    Kavanagh, Brian D.; Secomb, Timothy W.; Hsu, Richard; Lin, P.-S.; Venitz, Jurgen; Dewhirst, Mark W.

    2002-01-01

    Purpose: To develop a theoretical model for oxygen delivery to tumors, and to use the model to simulate the effects of changing the affinity of hemoglobin for oxygen on tumor oxygenation. Methods and Materials: Hemoglobin affinity is expressed in terms of P 50 , the partial pressure of oxygen (Po 2 ) at half saturation. Effects of changing P 50 on arterial Po 2 are predicted using an effective vessel approach to describe diffusive oxygen transport in the lungs, assuming fixed systemic oxygen demand and fixed blood flow rate. The decline in oxygen content of blood as it flows through normal tissue before entering the tumor region is assumed fixed. The hypoxic fraction of the tumor region is predicted using a three-dimensional simulation of diffusion from a network of vessels whose geometry is derived from observations of tumor microvasculature in the rat. Results: In air-breathing rats, predicted hypoxic fraction decreases with moderate increases in P 50 , but increases with further increases of P 50 , in agreement with previous experimental results. In rats breathing hyperoxic gases, and in humans breathing either normoxic or hyperoxic gases, increased P 50 is predicted to improve tumor oxygenation. Conclusions: The results support the administration of synthetic agents to increase P 50 during radiation treatment of tumors

  3. An update on the MTBE supply and demand picture

    International Nuclear Information System (INIS)

    Elkins, D.R.

    1993-01-01

    The initial Clean Air Act to establish emissions standards for automobiles and light-duty trucks was passed in 1966. It was modified in 1970 and again in 1977. In 1990 it was amended to present a 20 year plan to achieve cleaner air through fuel composition and vehicle design. This paper discusses the supply and demand within the US of methyl tertiary butyl ether as an oxygenated fuel additive to gasoline to help control the ozone pollution problem

  4. [Recent technical advances in portable oxygen delivery systems].

    Science.gov (United States)

    Machida, K; Kawabe, Y; Mori, M; Haga, T

    1992-08-01

    According to a Japanese national survey (June 30, 1990), the number of patients receiving home oxygen therapy (HOT) has been greater than 18,000 since March 1985, when HOT was first covered by health insurance. The oxygen concentrator, especially the molecular sieve type, is the most common method of delivery (more than 90%). In April 1988, the portable oxygen cylinder was acknowledged by health insurance, and the liquid oxygen supply system in April 1990. Three types of portable oxygen delivery systems are available; oxygen cyclinder, liquid oxygen system, and oxygen concentrator (membrane type), of which the oxygen cylinder is most commonly used. In our hospital, portable oxygen supply systems were used in 80% of 168 HOT cases in 1990, and the use of 400 L aluminum oxygen cylinders at a flow rate of 1-2 L/min has been most popular. There is an strong desire from patients for lighter portable oxygen supply system of longer duration. In 19 patients with chronic respiratory failure, we evaluated a newly designed demand oxygen delivery system (DODS), which weighs 2.4 kg including the DOD device (TER-20 Teijin), 1.1 L oxygen cylinder made of ultressor, nasal cannula, and carrier. Arterial blood gases at rest (room air) were PaO2 61.9 +/- 6.3 torr, PaCO2 63.8 +/- 9.4 torr and pH 7.40 +/- 0.04. A crossover trial was performed under three conditions; breathing room air with no weight, and pulse oxygen flow and continuous oxygen flow each carrying 2.4 kg of weight. Both 6 minute walking (E1) and walking on a slow speed treadmill (E2) were studied.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Voltage Controlled Dynamic Demand Response

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Mahat, Pukar

    2013-01-01

    Future power system is expected to be characterized by increased penetration of intermittent sources. Random and rapid fluctuations in demands together with intermittency in generation impose new challenges for power balancing in the existing system. Conventional techniques of balancing by large...... central or dispersed generations might not be sufficient for future scenario. One of the effective methods to cope with this scenario is to enable demand response. This paper proposes a dynamic voltage regulation based demand response technique to be applied in low voltage (LV) distribution feeders....... An adaptive dynamic model has been developed to determine composite voltage dependency of an aggregated load on feeder level. Following the demand dispatch or control signal, optimum voltage setting at the LV substation is determined based on the voltage dependency of the load. Furthermore, a new technique...

  6. Energy demand: Facts and trends

    Energy Technology Data Exchange (ETDEWEB)

    Chateau, B; Lapillonne, B

    1982-01-01

    The relationship between economic development and energy demand is investigated in this book. It gives a detailed analysis of the energy demand dynamics in industrialized countries and compares the past evolution of the driving factors behind energy demand by sector and by end-uses for the main OECD countries: residential sector (space heating, water heating, cooking...), tertiary sector, passenger and goods transport by mode, and industry (with particular emphasis on the steel and cement industry). This analysis leads to a more precise understanding of the long-term trends of energy demand; highlighting the influence on these trends of energy prices, especially after the oil price shocks, and of the type of economic development pattern.

  7. Temperature Effect on Energy Demand

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Duk [Korea Energy Economics Institute, Euiwang (Korea)

    1999-03-01

    We provide various estimates of temperature effect for accommodating seasonality in energy demand, particularly natural gas demand. We exploit temperature response and monthly temperature distribution to estimate the temperature effect on natural gas demand. Both local and global smoothed temperature responses are estimated from empirical relationship between hourly temperature and hourly energy consumption data during the sample period (1990 - 1996). Monthly temperature distribution estimates are obtained by kernel density estimation from temperature dispersion within a month. We integrate temperature response and monthly temperature density over all the temperatures in the sample period to estimate temperature effect on energy demand. Then, estimates of temperature effect are compared between global and local smoothing methods. (author). 15 refs., 14 figs., 2 tabs.

  8. Demand Response Spinning Reserve Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Eto, Joseph H.; Nelson-Hoffman, Janine; Torres, Carlos; Hirth,Scott; Yinger, Bob; Kueck, John; Kirby, Brendan; Bernier, Clark; Wright,Roger; Barat, A.; Watson, David S.

    2007-05-01

    The Demand Response Spinning Reserve project is a pioneeringdemonstration of how existing utility load-management assets can providean important electricity system reliability resource known as spinningreserve. Using aggregated demand-side resources to provide spinningreserve will give grid operators at the California Independent SystemOperator (CAISO) and Southern California Edison (SCE) a powerful, newtool to improve system reliability, prevent rolling blackouts, and lowersystem operating costs.

  9. Television Advertising and Soda Demand

    OpenAIRE

    Lopez, Rigoberto A.; Liu, Yizao; Zhu, Chen

    2012-01-01

    This study examines the effects of television advertising on consumer demand for carbonated soft drinks using a random coefficients logit model (BLP) with household and advertising data from seven U.S. cities over a three year period. We find that advertising decreases the price elasticity of demand, indicating that advertising plays predominantly a persuasive, therefore anti-competitive role in this market. Further results show that brand spillover effects are significant and that measuring ...

  10. Balancing supply and demand resources

    International Nuclear Information System (INIS)

    Sinha, J.; Saleeby, R.G.

    1990-01-01

    This article deals with using demand-side management (DSM) resources as an effective means of balancing supply and demand as a part of least-cost planning. The authors present a more sophisticated application of the load forecast adjustment method that reduces the number of DSM programs that need to be evaluated and provides blocks large enough to eliminate resolution problems in production costing models

  11. Integrated turbomachine oxygen plant

    Science.gov (United States)

    Anand, Ashok Kumar; DePuy, Richard Anthony; Muthaiah, Veerappan

    2014-06-17

    An integrated turbomachine oxygen plant includes a turbomachine and an air separation unit. One or more compressor pathways flow compressed air from a compressor through one or more of a combustor and a turbine expander to cool the combustor and/or the turbine expander. An air separation unit is operably connected to the one or more compressor pathways and is configured to separate the compressed air into oxygen and oxygen-depleted air. A method of air separation in an integrated turbomachine oxygen plant includes compressing a flow of air in a compressor of a turbomachine. The compressed flow of air is flowed through one or more of a combustor and a turbine expander of the turbomachine to cool the combustor and/or the turbine expander. The compressed flow of air is directed to an air separation unit and is separated into oxygen and oxygen-depleted air.

  12. Ambient oxygen promotes tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Ho Joong Sung

    2011-05-01

    Full Text Available Oxygen serves as an essential factor for oxidative stress, and it has been shown to be a mutagen in bacteria. While it is well established that ambient oxygen can also cause genomic instability in cultured mammalian cells, its effect on de novo tumorigenesis at the organismal level is unclear. Herein, by decreasing ambient oxygen exposure, we report a ∼50% increase in the median tumor-free survival time of p53-/- mice. In the thymus, reducing oxygen exposure decreased the levels of oxidative DNA damage and RAG recombinase, both of which are known to promote lymphomagenesis in p53-/- mice. Oxygen is further shown to be associated with genomic instability in two additional cancer models involving the APC tumor suppressor gene and chemical carcinogenesis. Together, these observations represent the first report directly testing the effect of ambient oxygen on de novo tumorigenesis and provide important physiologic evidence demonstrating its critical role in increasing genomic instability in vivo.

  13. Stochastic model of forecasting spare parts demand

    OpenAIRE

    Ivan S. Milojević; Rade V. Guberinić

    2012-01-01

    If demand is known for the whole planning period (complete information), then this type of demand or a supply system is deterministic. In the simplest cases, the demand per time unit is constant. If demand levels change over time following a precisely determined and pre-known principle, this type of demand is also classified as deterministic. This quality of demand is very rare. In most cases demand is the product of a process, for example TMS maintenance, whose progression cannot be predicte...

  14. 201-IJBCS-Article-Dr S O Ayoola

    African Journals Online (AJOL)

    RHUMSIKI

    Seasonal variation in fish distribution and physico-chemical parameters of wetland areas in Oyo ... The water pH, Biological Oxygen Demand (BOD) and Chemical Oxygen Demand ..... that low pH creates a stress situation in most organisms ...

  15. Hollow-fiber membrane bioreactor for the treatment of high-strength landfill leachate

    KAUST Repository

    Rizkallah, Marwan; El-Fadel, Mutasem E.; Saikaly, Pascal; Ayoub, George M.; Darwiche, Nadine D.; Hashisho, Jihan

    2013-01-01

    -fiber MBR. For this purpose, a laboratory-scale MBR was constructed and operated to treat leachate with a chemical oxygen demand (COD) of 9000-11,000 mg/l, a 5-day biochemical oxygen demand (BOD5) of 4000-6,000 mg/l, volatile suspended solids (VSS) of 300

  16. Influence of Hudiara Drain Water Irrigation on Trace Elements Load ...

    African Journals Online (AJOL)

    ... Drain Water Irrigation on Trace Elements Load In Soil And Uptake By Vegetables. ... This polluted water not only contains organic matter and crop nutrients but also ... Plant samples were collected at maturity from all the monitoring points. ... (DO), Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD) ...

  17. Selecting an oxygen plant for a copper smelter modernization

    Science.gov (United States)

    Larson, Kenneth H.; Hutchison, Robert L.

    1994-10-01

    The selection of an oxygen plant for the Cyprus Miami smelter modernization project began with a good definition of the use requirements and the smelter process variables that can affect oxygen demand. To achieve a reliable supply of oxygen with a reasonable amount of capital, critical equipment items were reviewed and reliability was added through the use of installed spares, purchase of insurance spare parts or the installation of equipment design for 50 percent of the production design such that the plant could operate with one unit while the other unit is being maintained. The operating range of the plant was selected to cover variability in smelter oxygen demand, and it was recognized that the broader operating range sacrificed about two to three percent in plant power consumption. Careful consideration of the plant "design point" was important to both the capital and operating costs of the plant, and a design point was specified that allowed a broad range of operation for maximum flexibility.

  18. Nitrogen fixation in the activated sludge treatment of thermomechanical pulping wastewater: effect of dissolved oxygen.

    Science.gov (United States)

    Slade, A H; Anderson, S M; Evans, B G

    2003-01-01

    N-ViroTech, a novel technology which selects for nitrogen-fixing bacteria as the bacteria primarily responsible for carbon removal, has been developed to treat nutrient limited wastewaters to a high quality without the addition of nitrogen, and only minimal addition of phosphorus. Selection of the operating dissolved oxygen level to maximise nitrogen fixation forms a key component of the technology. Pilot scale activated sludge treatment of a thermomechanical pulping wastewater was carried out in nitrogen-fixing mode over a 15 month period. The effect of dissolved oxygen was studied at three levels: 14% (Phase 1), 5% (Phase 2) and 30% (Phase 3). The plant was operated at an organic loading of 0.7-1.1 kg BOD5/m3/d, a solids retention time of approximately 10 d, a hydraulic retention time of 1.4 d and a F:M ratio of 0.17-0.23 mg BOD5/mg VSS/d. Treatment performance was very stable over the three dissolved oxygen operating levels. The plant achieved 94-96% BOD removal, 82-87% total COD removal, 79-87% soluble COD removal, and >99% total extractives removal. The lowest organic carbon removals were observed during operation at 30% DO but were more likely to be due to phosphorus limitation than operation at high dissolved oxygen, as there was a significant decrease in phosphorus entering the plant during Phase 3. Discharge of dissolved nitrogen, ammonium and oxidised nitrogen were consistently low (1.1-1.6 mg/L DKN, 0.1-0.2 mg/L NH4+-N and 0.0 mg/L oxidised nitrogen). Discharge of dissolved phosphorus was 2.8 mg/L, 0.1 mg/L and 0.6 mg/L DRP in Phases 1, 2 and 3 respectively. It was postulated that a population of polyphosphate accumulating bacteria developed during Phase 1. Operation at low dissolved oxygen during Phase 2 appeared to promote biological phosphorus uptake which may have been affected by raising the dissolved oxygen to 30% in Phase 3. Total nitrogen and phosphorus discharge was dependent on efficient secondary clarification, and improved over the course of

  19. Pattern of Demand For Money

    Directory of Open Access Journals (Sweden)

    Ahmad Berlian

    2017-12-01

    Full Text Available In the activity of the modern economy, the availability of money as a means of transaction is very important, because with the money as a means to pay consumers can easily to get the basic material needs are required, the manufacturer can provide the raw materials of labor for production, and distributors can obtain a variety of merchandise to be delivered at the end consumer. The pattern of use of money is influenced by the attitude of the public in the transaction. Researchers assume, that there are differences among communities, either by group differences in income, educational differences, ethnic differences, differences in profession, and perhaps even religious differences embraced. So as to provide information to the monetary authorities, to enrich the theory of demand for money based economic agents in Indonesia, and for the application of the theory of demand for money, the researchers felt the need to study patterns of use of money. Qualitative research, in addition to knowing whether the variables that affect the demand for money as the above theory is still relevant for economic actors in Indonesia at this time, or even are new variables, as well as the motive of money demand. Keywords: Demand for money, Keynes Theory, qualitative method

  20. Estimating oxygen needs for childhood pneumonia in developing country health systems: a new model for expecting the unexpected.

    Directory of Open Access Journals (Sweden)

    Beverly D Bradley

    Full Text Available Planning for the reliable and cost-effective supply of a health service commodity such as medical oxygen requires an understanding of the dynamic need or 'demand' for the commodity over time. In developing country health systems, however, collecting longitudinal clinical data for forecasting purposes is very difficult. Furthermore, approaches to estimating demand for supplies based on annual averages can underestimate demand some of the time by missing temporal variability.A discrete event simulation model was developed to estimate variable demand for a health service commodity using the important example of medical oxygen for childhood pneumonia. The model is based on five key factors affecting oxygen demand: annual pneumonia admission rate, hypoxaemia prevalence, degree of seasonality, treatment duration, and oxygen flow rate. These parameters were varied over a wide range of values to generate simulation results for different settings. Total oxygen volume, peak patient load, and hours spent above average-based demand estimates were computed for both low and high seasons.Oxygen demand estimates based on annual average values of demand factors can often severely underestimate actual demand. For scenarios with high hypoxaemia prevalence and degree of seasonality, demand can exceed average levels up to 68% of the time. Even for typical scenarios, demand may exceed three times the average level for several hours per day. Peak patient load is sensitive to hypoxaemia prevalence, whereas time spent at such peak loads is strongly influenced by degree of seasonality.A theoretical study is presented whereby a simulation approach to estimating oxygen demand is used to better capture temporal variability compared to standard average-based approaches. This approach provides better grounds for health service planning, including decision-making around technologies for oxygen delivery. Beyond oxygen, this approach is widely applicable to other areas of

  1. Energy supply and demand in California

    Science.gov (United States)

    Griffith, E. D.

    1978-01-01

    The author expresses his views on future energy demand on the west coast of the United States and how that energy demand translates into demand for major fuels. He identifies the major uncertainties in determining what future demands may be. The major supply options that are available to meet projected demands and the policy implications that flow from these options are discussed.

  2. International Oil Supplies and Demands

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-01

    The eleventh Energy Modeling Forum (EMF) working group met four times over the 1989--90 period to compare alternative perspectives on international oil supplies and demands through 2010 and to discuss how alternative supply and demand trends influence the world's dependence upon Middle Eastern oil. Proprietors of eleven economic models of the world oil market used their respective models to simulate a dozen scenarios using standardized assumptions. From its inception, the study was not designed to focus on the short-run impacts of disruptions on oil markets. Nor did the working group attempt to provide a forecast or just a single view of the likely future path for oil prices. The model results guided the group's thinking about many important longer-run market relationships and helped to identify differences of opinion about future oil supplies, demands, and dependence.

  3. Fundamental Travel Demand Model Example

    Science.gov (United States)

    Hanssen, Joel

    2010-01-01

    Instances of transportation models are abundant and detailed "how to" instruction is available in the form of transportation software help documentation. The purpose of this paper is to look at the fundamental inputs required to build a transportation model by developing an example passenger travel demand model. The example model reduces the scale to a manageable size for the purpose of illustrating the data collection and analysis required before the first step of the model begins. This aspect of the model development would not reasonably be discussed in software help documentation (it is assumed the model developer comes prepared). Recommendations are derived from the example passenger travel demand model to suggest future work regarding the data collection and analysis required for a freight travel demand model.

  4. International Oil Supplies and Demands

    International Nuclear Information System (INIS)

    1991-09-01

    The eleventh Energy Modeling Forum (EMF) working group met four times over the 1989--90 period to compare alternative perspectives on international oil supplies and demands through 2010 and to discuss how alternative supply and demand trends influence the world's dependence upon Middle Eastern oil. Proprietors of eleven economic models of the world oil market used their respective models to simulate a dozen scenarios using standardized assumptions. From its inception, the study was not designed to focus on the short-run impacts of disruptions on oil markets. Nor did the working group attempt to provide a forecast or just a single view of the likely future path for oil prices. The model results guided the group's thinking about many important longer-run market relationships and helped to identify differences of opinion about future oil supplies, demands, and dependence

  5. International Oil Supplies and Demands

    International Nuclear Information System (INIS)

    1992-04-01

    The eleventh Energy Modeling Forum (EMF) working group met four times over the 1989--1990 period to compare alternative perspectives on international oil supplies and demands through 2010 and to discuss how alternative supply and demand trends influence the world's dependence upon Middle Eastern oil. Proprietors of eleven economic models of the world oil market used their respective models to simulate a dozen scenarios using standardized assumptions. From its inception, the study was not designed to focus on the short-run impacts of disruptions on oil markets. Nor did the working group attempt to provide a forecast or just a single view of the likely future path for oil prices. The model results guided the group's thinking about many important longer-run market relationships and helped to identify differences of opinion about future oil supplies, demands, and dependence

  6. Consumer demand and quality assurance

    DEFF Research Database (Denmark)

    Grunert, Klaus G; Wognum, Nel; Trienekens, Jacques

    2011-01-01

    Consumers differ in their demands, and this mau have implications for the type of supply chain governance that is most suitable for serving them. We present a segmentation of pork consumers in the EU based on their food-related lifestyles and demand for different pork products. We then present...... an inventory of pork chain governance and quality management systems, also resulting from a pan-European study, and attempt to match types of chains to consumer segments, arguing that the type of quality demanded by the consumers has implications especially for the quality management system governing the chain......, and that these implications are different for fresh meat and processed meat. The paper closes with a call for more collaboration between chain researchers and consumer researchers....

  7. International Oil Supplies and Demands

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-01

    The eleventh Energy Modeling Forum (EMF) working group met four times over the 1989--1990 period to compare alternative perspectives on international oil supplies and demands through 2010 and to discuss how alternative supply and demand trends influence the world's dependence upon Middle Eastern oil. Proprietors of eleven economic models of the world oil market used their respective models to simulate a dozen scenarios using standardized assumptions. From its inception, the study was not designed to focus on the short-run impacts of disruptions on oil markets. Nor did the working group attempt to provide a forecast or just a single view of the likely future path for oil prices. The model results guided the group's thinking about many important longer-run market relationships and helped to identify differences of opinion about future oil supplies, demands, and dependence.

  8. North American supply/demand

    International Nuclear Information System (INIS)

    Pocino, M.C.

    1998-01-01

    The projected supply and demand for natural gas in five major regions of North America for the year 2000 was presented. In most regions, supply is expected to be greater than demand. A summary of how California dealt with an increase in natural gas demand in 1990 was presented. The California strategy included a readjustment of pipeline capacity, storage capacity and transportation. Whereas in the 1980s, when capacity was inadequate, the focus was on competition with alternate fuels, maximized capacity use, primary concern about reliability and only secondary concern about price, in the the 1990s, with excess capacity, the emphasis is on 'gas on gas' competition, efforts to satisfy the customer, primary concern about price, and only marginal concern about reliability. tabs., figs

  9. Climate change and energy demand

    International Nuclear Information System (INIS)

    Hengeveld, H.G.

    1991-01-01

    Climate and weather events affect energy demand in most economic sectors. Linear relationships exist between consumption and heating degree days, and peak electricity demand increases significantly during heat waves. The relative magnitudes of demand changes for a two times carbon dioxide concentration scenario are tabulated, illustrating heating degree days and cooling degree days for 5 Prairie locations. Irrigation, water management, crop seeding and harvesting and weed control are examples of climate-dependent agricultural activities involving significant energy use. The variability of summer season liquid fuel use in the agricultural sector in the Prairie provinces from 1984-1989 shows a relationship between agricultural energy use and regional climate fluctuations. 4 refs., 2 figs., 1 tab

  10. Supplies should match growing demand

    International Nuclear Information System (INIS)

    Rasmusen, H.J.

    1997-01-01

    The natural gas industry is currently enjoying healthy growth prospects. Not only is the demand for natural gas steadily growing; the outlook for increasing gas reserves is promising as well. The success of natural gas in the marketplace reflects, on one hand, continuous attention paid to public and customer requirements and, on the other hand, the ability of the gas industry to direct technological developments toward the increasing public demand for gas at competitive market prices supplied in a reliable, safe and environmentally friendly manner. In the past, the gas industry has been involved in the development of technologies for everything from gas production to the end user and from borehole to burner tip, and the author believes that the industry must continue or even increase its emphasis on technology in the future in order to capture new market opportunities. He explains this by looking at the supply side, the demand side and the structural side of the business

  11. Pay for load demand - electricity pricing with load demand component

    International Nuclear Information System (INIS)

    Pyrko, Jurek; Sernhed, Kerstin; Abaravicius, Juozas

    2003-01-01

    This publication is part of a project called Direct and Indirect Load Control in Buildings. Peak load problems have attracted considerable attention in Sweden during last three winters, caused by a significant decrease in available reserve power, which is a consequence of political decisions and liberalisation of the electricity market. A possible way to lower peak loads, avoiding electricity shortages and reducing electricity costs both for users and utilities, is to make customers experience the price difference during peak load periods and, in this way, become more aware of their energy consumption pattern and load demand. As of January 1st 2001, one of the Swedish energy utilities - Sollentuna Energi - operating in the Stockholm area, introduced a new electricity tariff with differentiated grid fees based on a mean value of the peak load every month. This tariff was introduced for all residential customers in the service area. The objective of this study is to investigate the extent to which a Load Demand Component, included in electricity pricing, can influence energy use and load demand in residential buildings. What are the benefits and disadvantages for customers and utilities? This paper investigates the impact of the new tariff on the utility and different types of typical residential customers, making comparisons with previous tariff. Keywords Load demand, electricity pricing, tariff, residential customers, energy behaviour

  12. Oxygen enrichment incineration

    International Nuclear Information System (INIS)

    Kim, Jeong Guk; Yang, Hee Chul; Park, Geun Il; Kim, Joon Hyung

    2000-10-01

    Oxygen enriched combustion technology has recently been used in waste incineration. To apply the oxygen enrichment on alpha-bearing waste incineration, which is being developed, a state-of-an-art review has been performed. The use of oxygen or oxygen-enriched air instead of air in incineration would result in increase of combustion efficiency and capacity, and reduction of off-gas product. Especially, the off-gas could be reduced below a quarter, which might reduce off-gas treatment facilities, and also increase an efficiency of off-gas treatment. However, the use of oxygen might also lead to local overheating and high nitrogen oxides (NOx) formation. To overcome these problems, an application of low NOx oxy-fuel burner and recycling of a part of off-gas to combustion chamber have been suggested

  13. Oxygen enrichment incineration

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Guk; Yang, Hee Chul; Park, Geun Il; Kim, Joon Hyung

    2000-10-01

    Oxygen enriched combustion technology has recently been used in waste incineration. To apply the oxygen enrichment on alpha-bearing waste incineration, which is being developed, a state-of-an-art review has been performed. The use of oxygen or oxygen-enriched air instead of air in incineration would result in increase of combustion efficiency and capacity, and reduction of off-gas product. Especially, the off-gas could be reduced below a quarter, which might reduce off-gas treatment facilities, and also increase an efficiency of off-gas treatment. However, the use of oxygen might also lead to local overheating and high nitrogen oxides (NOx) formation. To overcome these problems, an application of low NOx oxy-fuel burner and recycling of a part of off-gas to combustion chamber have been suggested.

  14. Demand as Frequency Controlled Reserve

    DEFF Research Database (Denmark)

    Xu, Zhao; Østergaard, Jacob; Togeby, Mikael

    2011-01-01

    Relying on generation side alone is deemed insufficient to fulfill the system balancing needs for future Danish power system, where a 50% wind penetration is outlined by the government for year 2025. This paper investigates using the electricity demand as frequency controlled reserve (DFR) as a new...... balancing measure, which has a high potential and can provide many advantages. Firstly, the background of the research is reviewed, including conventional power system reserves and the electricity demand side potentials. Subsequently, the control logics and corresponding design considerations for the DFR...

  15. Collusion and the elasticity of demand

    OpenAIRE

    David Collie

    2004-01-01

    The analysis of collusion in infinitely repeated Cournot oligopoly games has generally assumed that demand is linear, but this note uses constant-elasticity demand functions to investigate how the elasticity of demand affects the sustainability of collusion.

  16. EIA projections of coal supply and demand

    International Nuclear Information System (INIS)

    Klein, D.E.

    1989-01-01

    Contents of this report include: EIA projections of coal supply and demand which covers forecasted coal supply and transportation, forecasted coal demand by consuming sector, and forecasted coal demand by the electric utility sector; and policy discussion

  17. Metabolic Demands of Heavy Metal Drumming

    Directory of Open Access Journals (Sweden)

    Bryan Romero

    2016-07-01

    Full Text Available Background: The drum set involves dynamic movement of all four limbs. Motor control studies have been done on drum set playing, yet not much is known about the physiological responses to this activity. Even less is known about heavy metal drumming. Aims: The purpose of this study was to determine metabolic responses and demands of heavy metal drumming. Methods: Five semi-professional male drummers (mean ± SD age = 27.4 ± 2.6 y, height = 177.2 ± 3.8 cm, body mass = 85.1 ± 17.8 kg performed four prescribed and four self-selected heavy metal songs. Oxygen consumption (VO2, minute ventilation (VE and respiratory exchange ratio (RER were measured using a metabolic cart.  Heart rate (HR was measured using a heart rate monitor. VO2max was determined using a graded cycle ergometer test. Results: The results indicated a metabolic cost of 6.3 ± 1.4 METs and heart rate of 145.1 ± 15.7 beats·min-1 (75.4 ± 8.3% of age-predicted HRmax. VO2 peak values reached approximately 90% of the drummer’s VO2max when performing at the fastest speeds. According to these results, heavy metal drumming may be considered vigorous intensity activity (≥ 6.0 METs. The relative VO2max of 40.2 ± 9.5 mL·kg·min-1 leads to an aerobic fitness classification of “average” for adult males. Conclusions: The metabolic demands required during heavy metal drumming meet the American College of Sports Medicine guidelines for the development of health related fitness.  Keywords: Drum set, Exercise physiology, VO2, Music

  18. Separation of metabolic supply and demand: aerobic glycolysis as a normal physiological response to fluctuating energetic demands in the membrane.

    Science.gov (United States)

    Epstein, Tamir; Xu, Liping; Gillies, Robert J; Gatenby, Robert A

    2014-01-01

    Cancer cells, and a variety of normal cells, exhibit aerobic glycolysis, high rates of glucose fermentation in the presence of normal oxygen concentrations, also known as the Warburg effect. This metabolism is considered abnormal because it violates the standard model of cellular energy production that assumes glucose metabolism is predominantly governed by oxygen concentrations and, therefore, fermentative glycolysis is an emergency back-up for periods of hypoxia. Though several hypotheses have been proposed for the origin of aerobic glycolysis, its biological basis in cancer and normal cells is still not well understood. We examined changes in glucose metabolism following perturbations in membrane activity in different normal and tumor cell lines and found that inhibition or activation of pumps on the cell membrane led to reduction or increase in glycolysis, respectively, while oxidative phosphorylation remained unchanged. Computational simulations demonstrated that these findings are consistent with a new model of normal physiological cellular metabolism in which efficient mitochondrial oxidative phosphorylation supplies chronic energy demand primarily for macromolecule synthesis and glycolysis is necessary to supply rapid energy demands primarily to support membrane pumps. A specific model prediction was that the spatial distribution of ATP-producing enzymes in the glycolytic pathway must be primarily localized adjacent to the cell membrane, while mitochondria should be predominantly peri-nuclear. The predictions were confirmed experimentally. Our results show that glycolytic metabolism serves a critical physiological function under normoxic conditions by responding to rapid energetic demand, mainly from membrane transport activities, even in the presence of oxygen. This supports a new model for glucose metabolism in which glycolysis and oxidative phosphorylation supply different types of energy demand. Cells use efficient but slow-responding aerobic metabolism

  19. Consumer Demand for Major Foods in Egypt

    OpenAIRE

    Basem Fayaad; Stanley R. Johnson; Mohamed El-Khishin

    1995-01-01

    This study provides information on the structure of the consumer demand for major foods in Egypt. The information is in the form of key parameters for consumer demand systems. The modern theory of consumer behavior is the basis for estimating systems of demand equations. These systems yield estimates of own- and cross-price elasticities. The Linear Almost Ideal Demand System (LAIDS) model is applied in estimating a system of demand equations for food commodities. A full demand matrix results ...

  20. Intercity Travel Demand Analysis Model

    Directory of Open Access Journals (Sweden)

    Ming Lu

    2014-01-01

    Full Text Available It is well known that intercity travel is an important component of travel demand which belongs to short distance corridor travel. The conventional four-step method is no longer suitable for short distance corridor travel demand analysis for the time spent on urban traffic has a great impact on traveler's main mode choice. To solve this problem, the author studied the existing intercity travel demand analysis model, then improved it based on the study, and finally established a combined model of main mode choice and access mode choice. At last, an integrated multilevel nested logit model structure system was built. The model system includes trip generation, destination choice, and mode-route choice based on multinomial logit model, and it achieved linkage and feedback of each part through logsum variable. This model was applied in Shenzhen intercity railway passenger demand forecast in 2010 as a case study. As a result, the forecast results were consistent with the actuality. The model's correctness and feasibility were verified.

  1. Uranium. Resources, production and demand

    International Nuclear Information System (INIS)

    1997-01-01

    The events characterising the world uranium market in the last several years illustrate the persistent uncertainly faced by uranium producers and consumers worldwide. With world nuclear capacity expanding and uranium production satisfying only about 60 per cent of demand, uranium stockpiles continue to be depleted at a high rate. The uncertainty related to the remaining levels of world uranium stockpiles and to the amount of surplus defence material that will be entering the market makes it difficult to determine when a closer balance between uranium supply and demand will be reached. Information in this report provides insights into changes expected in uranium supply and demand until well into the next century. The 'Red Book', jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, is the foremost reference on uranium. This world report is based on official information from 59 countries and includes compilations of statistics on resources, exploration, production and demand as of 1 January 1997. It provides substantial new information from all of the major uranium producing centres in Africa, Australia, Eastern Europe, North America and the New Independent States, including the first-ever official reports on uranium production in Estonia, Mongolia, the Russian Federation and Uzbekistan. It also contains an international expert analysis of industry statistics and worldwide projections of nuclear energy growth, uranium requirements and uranium supply

  2. Criteria for demand response systems

    NARCIS (Netherlands)

    Lampropoulos, I.; Kling, W.L.; Bosch, van den P.P.J.; Ribeiro, P.F.; Berg, van den J.

    2013-01-01

    The topic of demand side management is currently becoming more important than ever, in parallel with the further deregulation of the electricity sector, and the increasing integration of renewable energy sources. A historical review of automation integration in power system control assists in

  3. The moral demands of affluence

    DEFF Research Database (Denmark)

    Sønderholm, Jørn

    2015-01-01

    In 2004, Garrett Cullity made a significant contribution to the literature on what the world’s relatively affluent owe to the world’s relatively poor through the publishing of The Moral Demands of Affluence. In this discussion note, I draw attention to a logical problem in Cullity’s master argument...

  4. Smart Buildings and Demand Response

    Science.gov (United States)

    Kiliccote, Sila; Piette, Mary Ann; Ghatikar, Girish

    2011-11-01

    Advances in communications and control technology, the strengthening of the Internet, and the growing appreciation of the urgency to reduce demand side energy use are motivating the development of improvements in both energy efficiency and demand response (DR) systems in buildings. This paper provides a framework linking continuous energy management and continuous communications for automated demand response (Auto-DR) in various times scales. We provide a set of concepts for monitoring and controls linked to standards and procedures such as Open Automation Demand Response Communication Standards (OpenADR). Basic building energy science and control issues in this approach begin with key building components, systems, end-uses and whole building energy performance metrics. The paper presents a framework about when energy is used, levels of services by energy using systems, granularity of control, and speed of telemetry. DR, when defined as a discrete event, requires a different set of building service levels than daily operations. We provide examples of lessons from DR case studies and links to energy efficiency.

  5. Consumer surplus and CES demand

    NARCIS (Netherlands)

    ten Raa, Thijs

    2015-01-01

    This article presents the consumer surplus formula for constant elasticity of substitution (CES) demands. The formula is used to compare the monopoly and optimum provisions of product variety. It is shown that a monopolist under-provides variety. This result is contrasted with Lambertini’s analysis

  6. Projecting Electricity Demand in 2050

    Energy Technology Data Exchange (ETDEWEB)

    Hostick, Donna J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Belzer, David B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hadley, Stanton W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Markel, Tony [National Renewable Energy Lab. (NREL), Golden, CO (United States); Marnay, Chris [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Kintner-Meyer, Michael C. W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-07-01

    This paper describes the development of end-use electricity projections and load curves that were developed for the Renewable Electricity (RE) Futures Study (hereafter RE Futures), which explored the prospect of higher percentages (30% - 90%) of total electricity generation that could be supplied by renewable sources in the United States. As input to RE Futures, two projections of electricity demand were produced representing reasonable upper and lower bounds of electricity demand out to 2050. The electric sector models used in RE Futures required underlying load profiles, so RE Futures also produced load profile data in two formats: 8760 hourly data for the year 2050 for the GridView model, and in 2-year increments for 17 time slices as input to the Regional Energy Deployment System (ReEDS) model. The process for developing demand projections and load profiles involved three steps: discussion regarding the scenario approach and general assumptions, literature reviews to determine readily available data, and development of the demand curves and load profiles.

  7. The Cognitive Demands of Writing

    NARCIS (Netherlands)

    Torrance, Mark; Jeffery, Gaynor

    1999-01-01

    Writing is a complex activity that places demands on cognitive resources. This volume presents original theory and research exploring the ways in which the sub-components of the writing process (generating and organizing content, producing grammatical sentences, etc.) differ in their cognitive

  8. Demand Controlled Ventilation and Classroom Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Davies, Molly [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eliseeva, Ekaterina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faulkner, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hong, Tienzen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sullivan, Douglas P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-05-01

    This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling.

  9. Demand controlled ventilation and classroom ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Davies, Molly [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eliseeva, Ekaterina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faulkner, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hong, Tienzen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sullivan, Douglas P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-01-06

    This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling.

  10. Demand as frequency controlled reserve

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Z.; Togeby, M.; OEstergaard, J.

    2008-09-15

    Using demand as frequency controlled reserve (DFR) is an emerging technology which allow demand to participate actively in maintaining the system operation without reducing the energy service delivered to the customer and without need of user interaction. The basic premise is that traditional frequency controlled reserves from power plants and interconnections with neighbouring systems can be costly, slow and not fulfil the need for future power grids with a high share of wind power and fewer central power plants, and an intention to perform flexible operation such as is landing. Electricity demands, on the other hand, have advantages as frequency reserve including fast activation speed, smooth linear activation, low expected costs, and well-dispersed in the distribution grid. The main challenge of DFR is new methods for monitoring the available capacity. This project has investigated the technology of using electricity demands for providing frequency reserve to power systems. Within the project the potential and economy of DFR compatible loads in Denmark has been investigated, control logic has been designed, power system impact has been investigated, potential business models has been evaluated and an implementation strategy has been suggested. The tasks and goals of the project have been successfully accomplished based on which the conclusion and future recommendation are made. This project has developed the DFR technology that enables electricity demands to autonomously disconnect or reconnect to the grid in response to system frequency variations. The developed DFR technology is proved to be a promising technology from several perspectives. Technically, using DFR is feasible to provide reserves and enhance power system frequency control, while fulfilling technical requirements such as linear activation (or reconnection) according to frequency (or time). Environmentally, the DFR technology is pollution free in contrast to traditional reserves from generation

  11. Diurnal variations in wastewater characteristics at main out fall in Lahore

    International Nuclear Information System (INIS)

    Haider, H.; Ali, W.; Ali, W.

    2012-01-01

    Variations in the flow and pollutants concentrations during the day were monitored at the Main Out fall disposal station of the city of Lahore. The laboratory analysis of the wastewater samples collected at 2 hour interval on fifth and sixth May, 2009 for pH, temperature, alkalinity, hardness, Biochemical Oxygen Demand (BOD5), BOD5 Filtered, Total Kjeldahl Nitrogen (TKN), Ammonia Nitrogen (NH/sub 3/-N), chlorides, solids, turbidity, sulphates and nitrates were carried out. Average values and standard deviations were determined to assess the type of wastewater treatment. Correlation between BOD5 and BOD5 Filtered was developed through regression analysis. Diurnal variations in the Ultimate Biochemical Oxygen Demand (BODU) at the Main Out fall based on Carbonaceous Biochemical Oxygen Demand (CBODU) and Nitrogenous Biochemical Oxygen Demand (NBODU) are also estimated. The ratio between CBODU/NBODU ranges between 0.86 to 1.8 during a day at Main Out fall. This variation is primarily due to the large diurnal variation in CBODU values as a result of industrial activities in the study area. The BOD5/ TKN ratio varies between 3.3 and 6.9 and the calculated BODU (i.e., CBODU + NBODU) was found to be almost double of BOD5 during most part of the day primarily due to inclusion of NBOD. The study results reveal the importance of NBOD while designing the wastewater treatment facilities and implementing a water quality control strategy for the River Ravi. (author)

  12. Addressing Energy Demand through Demand Response. International Experiences and Practices

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Bo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ghatikar, Girish [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ni, Chun Chun [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dudley, Junqiao [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Martin, Phil [Enernoc, Inc., Boston, MA (United States); Wikler, Greg

    2012-06-01

    Demand response (DR) is a load management tool which provides a cost-effective alternative to traditional supply-side solutions to address the growing demand during times of peak electrical load. According to the US Department of Energy (DOE), demand response reflects “changes in electric usage by end-use customers from their normal consumption patterns in response to changes in the price of electricity over time, or to incentive payments designed to induce lower electricity use at times of high wholesale market prices or when system reliability is jeopardized.” 1 The California Energy Commission (CEC) defines DR as “a reduction in customers’ electricity consumption over a given time interval relative to what would otherwise occur in response to a price signal, other financial incentives, or a reliability signal.” 2 This latter definition is perhaps most reflective of how DR is understood and implemented today in countries such as the US, Canada, and Australia where DR is primarily a dispatchable resource responding to signals from utilities, grid operators, and/or load aggregators (or DR providers).

  13. Simultaneous sampling of tissue oxygenation and oxygen consumption in skeletal muscle.

    Science.gov (United States)

    Nugent, William H; Song, Bjorn K; Pittman, Roland N; Golub, Aleksander S

    2016-05-01

    Under physiologic conditions, microvascular oxygen delivery appears to be well matched to oxygen consumption in respiring tissues. We present a technique to measure interstitial oxygen tension (PISFO2) and oxygen consumption (VO2) under steady-state conditions, as well as during the transitions from rest to activity and back. Phosphorescence Quenching Microscopy (PQM) was employed with pneumatic compression cycling to achieve 1 to 10 Hz sampling rates of interstitial PO2 and simultaneous recurrent sampling of VO2 (3/min) in the exteriorized rat spinotrapezius muscle. The compression pressure was optimized to 120-130 mmHg without adverse effect on the tissue preparation. A cycle of 5s compression followed by 15s recovery yielded a resting VO2 of 0.98 ± 0.03 ml O2/100 cm(3)min while preserving microvascular oxygen delivery. The measurement system was then used to assess VO2 dependence on PISFO2 at rest and further tested under conditions of isometric muscle contraction to demonstrate a robust ability to monitor the on-kinetics of tissue respiration and the compensatory changes in PISFO2 during contraction and recovery. The temporal and spatial resolution of this approach is well suited to studies seeking to characterize microvascular oxygen supply and demand in thin tissues. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Effects of Fiber Type and Size on the Heterogeneity of Oxygen Distribution in Exercising Skeletal Muscle

    Science.gov (United States)

    Liu, Gang; Mac Gabhann, Feilim; Popel, Aleksander S.

    2012-01-01

    The process of oxygen delivery from capillary to muscle fiber is essential for a tissue with variable oxygen demand, such as skeletal muscle. Oxygen distribution in exercising skeletal muscle is regulated by convective oxygen transport in the blood vessels, oxygen diffusion and consumption in the tissue. Spatial heterogeneities in oxygen supply, such as microvascular architecture and hemodynamic variables, had been observed experimentally and their marked effects on oxygen exchange had been confirmed using mathematical models. In this study, we investigate the effects of heterogeneities in oxygen demand on tissue oxygenation distribution using a multiscale oxygen transport model. Muscles are composed of different ratios of the various fiber types. Each fiber type has characteristic values of several parameters, including fiber size, oxygen consumption, myoglobin concentration, and oxygen diffusivity. Using experimentally measured parameters for different fiber types and applying them to the rat extensor digitorum longus muscle, we evaluated the effects of heterogeneous fiber size and fiber type properties on the oxygen distribution profile. Our simulation results suggest a marked increase in spatial heterogeneity of oxygen due to fiber size distribution in a mixed muscle. Our simulations also suggest that the combined effects of fiber type properties, except size, do not contribute significantly to the tissue oxygen spatial heterogeneity. However, the incorporation of the difference in oxygen consumption rates of different fiber types alone causes higher oxygen heterogeneity compared to control cases with uniform fiber properties. In contrast, incorporating variation in other fiber type-specific properties, such as myoglobin concentration, causes little change in spatial tissue oxygenation profiles. PMID:23028531

  15. Demand chain management - The evolution

    Directory of Open Access Journals (Sweden)

    D Ericsson

    2011-06-01

    Full Text Available The concepts of Supply Chain Management (SCM and Demand Chain Management (DCM are among the new and debated topics concerning logistics in the literature. The question considered in this paper is: “Are these concepts needed or will they just add to the confusion?” Lasting business concepts have always evolved in close interaction between business and academia. Different approaches start out in business and they are then, more or less si- multaneously, aligned, integrated, systemised and structured in academia. In this way a terminology (or language is provided that helps in further diffusion of the concepts. There is a lack of consensus on the definition of the concept of SCM. This may be one of the major reasons for the difficulty in advancing the science and measuring the results of implementation in business. Relationships in SCM span from rather loose coalitions to highly structured virtual network integrations. DCM is a highly organised chain in which the key is mutual interdependence and partnership. The purpose is to create a distinctive competence for the chain as a whole that helps to identify and satisfy customer needs and wishes. The classical research concerning vertical marketing systems is very helpful in systemising the rather unstructured discussions in current SCM research. The trend lies in increasing competition between channels rather than between companies, which in turn leads to the creation of channels with a high degree of partnership and mutual interdependence between members. These types of channels are known as organised vertical marketing systems in the classic marketing channel research. The behaviour in these types of channels, as well as the formal and informal structures, roles in the network, power and dependence relations, etc. are well covered topics in the literature. The concept of vertical marketing systems lies behind the definition of demand chains and demand chain management proposed in this paper. A

  16. High Selectivity Oxygen Delignification

    Energy Technology Data Exchange (ETDEWEB)

    Lucian A. Lucia

    2005-11-15

    Project Objective: The objectives of this project are as follows: (1) Examine the physical and chemical characteristics of a partner mill pre- and post-oxygen delignified pulp and compare them to lab generated oxygen delignified pulps; (2) Apply the chemical selectivity enhancement system to the partner pre-oxygen delignified pulps under mill conditions (with and without any predetermined amounts of carryover) to determine how efficiently viscosity is preserved, how well selectivity is enhanced, if strength is improved, measure any yield differences and/or bleachability differences; and (3) Initiate a mill scale oxygen delignification run using the selectivity enhancement agent, collect the mill data, analyze it, and propose any future plans for implementation.

  17. Optic nerve oxygenation

    DEFF Research Database (Denmark)

    Stefánsson, Einar; Pedersen, Daniella Bach; Jensen, Peter Koch

    2005-01-01

    The oxygen tension of the optic nerve is regulated by the intraocular pressure and systemic blood pressure, the resistance in the blood vessels and oxygen consumption of the tissue. The oxygen tension is autoregulated and moderate changes in intraocular pressure or blood pressure do not affect...... the optic nerve oxygen tension. If the intraocular pressure is increased above 40 mmHg or the ocular perfusion pressure decreased below 50 mmHg the autoregulation is overwhelmed and the optic nerve becomes hypoxic. A disturbance in oxidative metabolism in the cytochromes of the optic nerve can be seen...... at similar levels of perfusion pressure. The levels of perfusion pressure that lead to optic nerve hypoxia in the laboratory correspond remarkably well to the levels that increase the risk of glaucomatous optic nerve atrophy in human glaucoma patients. The risk for progressive optic nerve atrophy in human...

  18. Pathology of oxygen

    National Research Council Canada - National Science Library

    Autor, Anne Pomeroy

    1982-01-01

    This volume has been designed to provide those interested in oxygen toxicity with a working knowledge of advancement in the field with the intention that the topics described in each chapter will be immediately useful...

  19. Using oxygen at home

    Science.gov (United States)

    ... at Home Tell your local fire department, electric company, and telephone company that you use oxygen in your home. They ... M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health ...

  20. Pathology of oxygen

    National Research Council Canada - National Science Library

    Autor, Anne Pomeroy

    1982-01-01

    .... The book is divided into three general sections. The first and smallest section of the book explains the molecular and biochemical basis of our current understanding of oxygen radical toxicity as well as the means by which normal aerobic cells...

  1. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    la Cour, M; Kiilgaard, Jens Folke; Eysteinsson, T

    2000-01-01

    To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide.......To investigate the influence of acute changes in intraocular pressure on the oxygen tension in the vicinity of the optic nerve head under control conditions and after intravenous administration of 500 mg of the carbonic anhydrase inhibitor dorzolamide....

  2. Ekstrakorporal oxygenering ved legionellapneumoni

    DEFF Research Database (Denmark)

    Uslu, Bülent; Steensen, Morten

    2009-01-01

    We present a case report with a 49-year-old woman with legionella pneumonia and fulminant respiratory failure. Despite maximal conventional respirator treatment with positive pressure ventilation, 100% oxygen and pharmacological treatment in an intensive care unit, further deterioration with hypo......We present a case report with a 49-year-old woman with legionella pneumonia and fulminant respiratory failure. Despite maximal conventional respirator treatment with positive pressure ventilation, 100% oxygen and pharmacological treatment in an intensive care unit, further deterioration...

  3. Intraportal islet oxygenation.

    Science.gov (United States)

    Suszynski, Thomas M; Avgoustiniatos, Efstathios S; Papas, Klearchos K

    2014-05-01

    Islet transplantation (IT) is a promising therapy for the treatment of diabetes. The large number of islets required to achieve insulin independence limit its cost-effectiveness and the number of patients who can be treated. It is believed that >50% of islets are lost in the immediate post-IT period. Poor oxygenation in the early post-IT period is recognized as a possible reason for islet loss and dysfunction but has not been extensively studied. Several key variables affect oxygenation in this setting, including (1) local oxygen partial pressure (pO(2)), (2) islet oxygen consumption, (3) islet size (diameter, D), and (4) presence or absence of thrombosis on the islet surface. We discuss implications of oxygen-limiting conditions on intraportal islet viability and function. Of the 4 key variables, the islet size appears to be the most important determinant of the anoxic and nonfunctional islet volume fractions. Similarly, the effect of thrombus formation on the islet surface may be substantial. At the University of Minnesota, average size distribution data from clinical alloislet preparations (n = 10) indicate that >150-µm D islets account for only ~30% of the total islet number, but >85% of the total islet volume. This suggests that improved oxygen supply to the islets may have a profound impact on islet survivability and function since most of the β-cell volume is within large islets which are most susceptible to oxygen-limiting conditions. The assumption that the liver is a suitable islet transplant site from the standpoint of oxygenation should be reconsidered. © 2014 Diabetes Technology Society.

  4. DataBase on Demand

    International Nuclear Information System (INIS)

    Aparicio, R Gaspar; Gomez, D; Wojcik, D; Coz, I Coterillo

    2012-01-01

    At CERN a number of key database applications are running on user-managed MySQL database services. The database on demand project was born out of an idea to provide the CERN user community with an environment to develop and run database services outside of the actual centralised Oracle based database services. The Database on Demand (DBoD) empowers the user to perform certain actions that had been traditionally done by database administrators, DBA's, providing an enterprise platform for database applications. It also allows the CERN user community to run different database engines, e.g. presently open community version of MySQL and single instance Oracle database server. This article describes a technology approach to face this challenge, a service level agreement, the SLA that the project provides, and an evolution of possible scenarios.

  5. Advertising media and cigarette demand.

    Science.gov (United States)

    Goel, Rajeev K

    2011-01-01

    Using state-level panel data for the USA spanning three decades, this research estimates the demand for cigarettes. The main contribution lies in studying the effects of cigarette advertising disaggregated across five qualitatively different groups. Results show cigarette demand to be near unit elastic, the income effects to be generally insignificant and border price effects and habit effects to be significant. Regarding advertising effects, aggregate cigarette advertising has a negative effect on smoking. Important differences across advertising media emerge when cigarette advertising is disaggregated. The effects of public entertainment and Internet cigarette advertising are stronger than those of other media. Anti-smoking messages accompanying print cigarette advertising seem relatively more effective. Implications for smoking control policy are discussed.

  6. Uranium Resources, production and demand

    International Nuclear Information System (INIS)

    1988-01-01

    Periodic assessments of world uranium supply and demand have been conducted by the OECD Nuclear Energy Agency (NEA) and the International Atomic Energy Agency (IAEA) since the mid 1960s. Published every two years, the report URANIUM RESOURCES, PRODUCTION AND DEMAND, commonly referred to as the RED BOOK, has become an essential reference document for nuclear planners and policy makers in the international nuclear community. The latest Red Book, published in 1988, was based on data collected mainly in early 1987. Most of the data for 1987 were therefore provisional. The STATISTICAL UPDATE 1988 provides updated 1987 data collected in 1988 and provisional data for 1988. The publication, which covers OECD Countries and gives Secretariat estimates for the rest of the World Outside Centrally Planned Economies (WOCA), is being issued every second year, between publications of more complete Red Books

  7. Enrichment demand boosts SWU prices

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The enrichment market is picking up significantly on very brisk demand. US utilities, which normally purchase material nine months to a year ahead of time, are already hitting the market to fill their 1996 requirements. In June, two non-US utilities, one European entity and a US utility bought SWUs, the entity in an off-market deal. But that doesn't tell the whole story. Three other US utilities entered the market during the month. Meanwhile, we count 13 more utilities getting ready to hit the market for more than 4 million SWUs. Why the surge in demand? Utilities, uncertain of the role to be played by the new US Enrichment Corp. and seeking to take advantage of low interest rates, are implementing buy and hold strategies. As a result, the upper end of NUKEM's SWU price range inched up to $78. The lower end dipped to $67 based on the European deal

  8. Singlet oxygen quenching by oxygen in tetraphenyl-porphyrin solutions

    International Nuclear Information System (INIS)

    Dedic, Roman; Korinek, Miloslav; Molnar, Alexander; Svoboda, Antonin; Hala, Jan

    2006-01-01

    Time-resolved measurement of singlet oxygen infrared phosphorescence is a powerful tool for determination of quantum yields and kinetics of its photosensitization. This technique was employed to investigate in detail the previously observed effect of singlet oxygen quenching by oxygen. The question whether the singlet oxygen is quenched by oxygen in ground or in excited state was addressed by study of two complementary dependencies of singlet oxygen lifetimes: on dissolved oxygen concentration and on excitation intensity. Oxygen concentration dependence study of meso-tetra(4-sulphonato)phenylporphyrin (TPPS 4 ) phosphorescence kinetics showed linearity of the dependence of TPPS 4 triplet state rate-constant. Corresponding bimolecular quenching constant of (1.5±0.1)x10 9 l/mol s was obtained. On the other hand, rate constants of singlet oxygen depopulation exhibit nonlinear dependence on oxygen concentration. Comparison of zero oxygen concentration-extrapolated value of singlet oxygen lifetime of (6.5±0.4) μs to (3.7±0.1) μs observed under air-saturated conditions indicates importance of the effect of quenching of singlet oxygen by oxygen. Upward-sloping dependencies of singlet oxygen depopulation rate-constant on excitation intensity evidence that singlet oxygen is predominantly quenched by oxygen in excited singlet state

  9. Demand controlled ventilation; Behovsstyrt ventilasjon

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Henning Holm

    2006-07-01

    The terms CAV and VAV have been known terms for many years in the ventilation business. The terms are also included in building regulations, but the time is now right to focus on demand controlled ventilation (DCV). The new building regulations and the accompanying energy framework underline the need for a more nuanced thinking when it comes to controlling ventilation systems. Descriptions and further details of the ventilation systems are provided (ml)

  10. Strong demand for natural uranium

    International Nuclear Information System (INIS)

    Kalinowski, P.

    1975-01-01

    The Deutsches Atomforum and the task group 'fuel elements' of the Kerntechnische Gesellschaft had organized an international two-day symposium in Mainz on natural uranium supply which was attended by 250 experts from 20 countries. The four main themes were: Demand for natural uranium, uranium deposits and uranium production, attitude of the uranium producing countries, and energy policy of the industrial nations. (orig./AK) [de

  11. Alcohol demand and risk preference.

    Science.gov (United States)

    Dave, Dhaval; Saffer, Henry

    2008-12-01

    Both economists and psychologists have studied the concept of risk preference. Economists categorize individuals as more or less risk-tolerant based on the marginal utility of income. Psychologists categorize individuals' propensity towards risk based on harm avoidance, novelty seeking and reward dependence traits. The two concepts of risk are related, although the instruments used for empirical measurement are quite different. Psychologists have found risk preference to be an important determinant of alcohol consumption; however economists have not included risk preference in studies of alcohol demand. This is the first study to examine the effect of risk preference on alcohol consumption in the context of a demand function. The specifications employ multiple waves from the Panel Study of Income Dynamics (PSID) and the Health and Retirement Study (HRS), which permit the estimation of age-specific models based on nationally representative samples. Both of these data sets include a unique and consistent survey instrument designed to directly measure risk preference in accordance with the economist's definition. This study estimates the direct impact of risk preference on alcohol demand and also explores how risk preference affects the price elasticity of demand. The empirical results indicate that risk preference has a significant negative effect on alcohol consumption, with the prevalence and consumption among risk-tolerant individuals being 6-8% higher. Furthermore, the tax elasticity is similar across both risk-averse and risk-tolerant individuals. This suggests that tax policies are as equally effective in deterring alcohol consumption among those who have a higher versus a lower propensity for alcohol use.

  12. Millennium bim managing growing demand

    OpenAIRE

    Lopes, Francisca Barbosa Malpique de Paiva

    2014-01-01

    Millennium bim, the Mozambican operation of Millennium bcp group, was the Company selected to serve as background for the development of a teaching case in Marketing. This case is followed by a teaching note, and is intended to be used as a pedagogical tool in undergraduate and/or graduate programs. Even though Mozambique is still characterized by high financial exclusion, the number of people entering within the banking industry has been growing at a fast pace. Actually, the demand for fi...

  13. Demand for healthcare in India

    Directory of Open Access Journals (Sweden)

    Brijesh C. Purohit

    2013-03-01

    Full Text Available In a developing country like India, allocation of scarce fiscal resources has to be based on a clear understanding of how investments in the heath sector are going to affect demand. Three aspects like overall healthcare demand, consumer decisions to use public and/or private care and role of price/quality influencing poor/rich consumer’s decisions are critical to assessing the equity implications of alternative policies. Our paper addresses these aspects through examining the pattern of healthcare demand in India. Data from the National Family Health Survey are used to model the healthcare choices that individuals make. We consider what these behavioral characteristics imply for public policy. This analysis aims to study disparities between rural and urban areas from all throughout India to five Indian states representing three levels of per capita incomes (all-India average, rich and poor. Results evidence that healthcare demand both in rural and urban areas is a commodity emerging as an essential need. Choices between public or private provider are guided by income and quality variables mainly with regard to public healthcare denoting thus a situation of very limited alternatives in terms of availing private providers. These results emphasize that existing public healthcare facilities do not serve the objective of providing care to the poor in a satisfactory manner in rural areas. Thus, any financing strategy to improve health system and reduce disparities across rich-poor states and rural-urban areas should also take into account not only overcoming inadequacy but also inefficiency in allocation and utilization of healthcare inputs.

  14. Uranium resources, production and demand

    International Nuclear Information System (INIS)

    1988-01-01

    Nuclear power-generating capacity will continue to expand, albeit at a slower pace than during the past fifteen years. This expansion must be matched by an adequately increasing supply of uranium. This report compares uranium supply and demand data in free market countries with the nuclear industry's natural uranium requirements up to the year 2000. It also reviews the status of uranium exploration, resources and production in 46 countries

  15. The economics of uranium demand

    International Nuclear Information System (INIS)

    Owen, A.D.

    1983-01-01

    The major characteristics of the demand for uranium are identified, and a number of factors which determine the actual level of uranium requirements of the nuclear power industry are discussed. Since the role of inventories is central to the process of short-term price formation, by comparing projections of uranium production and apparent consumption, the relative level of total inventories is calculated and an assessment is made of its likely impact on the uranium market during the 1980s. (author)

  16. Forecasting Croatian inbound tourism demand

    OpenAIRE

    Tica, Josip; Kožić, Ivan

    2015-01-01

    The aim of this paper is to present a forecasting model for the overnight stays of foreign tourists in Croatia. Tourism is one of the most important parts of the Croatian economy. It is particularly important in the context of the services sector. Regular and significant surpluses and the consumption of foreign guests are an important element of budget revenues, especially VAT. The ability to forecast the development of inbound tourism demand in a timely manner is crucial for both business...

  17. Optimal Advertising with Stochastic Demand

    OpenAIRE

    George E. Monahan

    1983-01-01

    A stochastic, sequential model is developed to determine optimal advertising expenditures as a function of product maturity and past advertising. Random demand for the product depends upon an aggregate measure of current and past advertising called "goodwill," and the position of the product in its life cycle measured by sales-to-date. Conditions on the parameters of the model are established that insure that it is optimal to advertise less as the product matures. Additional characteristics o...

  18. Demand, Energy, and Power Factor

    Science.gov (United States)

    1994-08-01

    POWER FACTOR DEFINITION I Basically , power factor (pf) is a measure of how effectively the plant uses the electricity it purchases from the utility. It...not be made available by the plant. U 24 This video is relatively short, less than fifteen-minutes, and covers the basics on demand, block extenders... ratemaking methodology and test period as used in determining the NC-RS rates. Pending final decision by the FERC, the Federal Government would pay a rate as

  19. World gas supply-demand

    International Nuclear Information System (INIS)

    Rushby, I.L.

    1996-01-01

    The rapid growth in demand for natural gas from a global perspective is documented in this paper. Low prices compared to other fuels and a return to normal winter temperatures is argued to be the cause of this increase in consumption. Natural gas production and prices for 1995 are discussed and forecasts made for future years, in particular the prospects for LNG in Asia. Data on energy growth and gas specific information in world markets are included. (UK)

  20. Automation of energy demand forecasting

    Science.gov (United States)

    Siddique, Sanzad

    Automation of energy demand forecasting saves time and effort by searching automatically for an appropriate model in a candidate model space without manual intervention. This thesis introduces a search-based approach that improves the performance of the model searching process for econometrics models. Further improvements in the accuracy of the energy demand forecasting are achieved by integrating nonlinear transformations within the models. This thesis introduces machine learning techniques that are capable of modeling such nonlinearity. Algorithms for learning domain knowledge from time series data using the machine learning methods are also presented. The novel search based approach and the machine learning models are tested with synthetic data as well as with natural gas and electricity demand signals. Experimental results show that the model searching technique is capable of finding an appropriate forecasting model. Further experimental results demonstrate an improved forecasting accuracy achieved by using the novel machine learning techniques introduced in this thesis. This thesis presents an analysis of how the machine learning techniques learn domain knowledge. The learned domain knowledge is used to improve the forecast accuracy.

  1. Energy demand and population change.

    Science.gov (United States)

    Allen, E L; Edmonds, J A

    1981-09-01

    During the post World War 2 years energy consumption has grown 136% while population grew about 51%; per capita consumption of energy expanded, therefore, about 60%. For a given population size, demographic changes mean an increase in energy needs; for instance the larger the group of retirement age people, the smaller their energy needs than are those for a younger group. Estimates indicate that by the year 2000 the energy impact will be toward higher per capita consumption with 60% of the population in the 19-61 age group of workers. Rising female labor force participation will increase the working group even more; it has also been found that income and energy grow at a proportional rate. The authors predict that gasoline consumption within the US will continue to rise with availability considering the larger number of female drivers and higher per capita incomes. The flow of illegal aliens (750,000/year) will have a major impact on income and will use greater amounts of energy than can be expected. A demographic change which will lower energy demands will be the slowdown of the rate of household formation caused by the falling number of young adults. The response of energy demand to price changes is small and slow but incomes play a larger role as does the number of personal automobiles and social changes affecting household formation. Households, commercial space, transportation, and industry are part of every demand analysis and population projections play a major role in determining these factors.

  2. Demand for radiotherapy in Spain.

    Science.gov (United States)

    Rodríguez, A; Borrás, J M; López-Torrecilla, J; Algara, M; Palacios-Eito, A; Gómez-Caamaño, A; Olay, L; Lara, P C

    2017-02-01

    Assessing the demand for radiotherapy in Spain based on existing evidence to estimate the human resources and equipment needed so that every person in Spain has access to high-quality radiotherapy when they need it. We used data from the European Cancer Observatory on the estimated incidence of cancer in Spain in 2012, along with the evidence-based indications for radiotherapy developed by the Australian CCORE project, to obtain an optimal radiotherapy utilisation proportion (OUP) for each tumour. About 50.5 % of new cancers in Spain require radiotherapy at least once over the course of the disease. Additional demand for these services comes from reradiation therapy and non-melanoma skin cancer. Approximately, 25-30 % of cancer patients with an indication for radiotherapy do not receive it due to factors that include access, patient preference, familiarity with the treatment among physicians, and especially resource shortages, all of which contribute to its underutilisation. Radiotherapy is underused in Spain. The increasing incidence of cancer expected over the next decade and the greater frequency of reradiations necessitate the incorporation of radiotherapy demand into need-based calculations for cancer services planning.

  3. Demands from the school inclusion

    Directory of Open Access Journals (Sweden)

    Selma Norberto Matos

    2014-04-01

    Full Text Available From the implementation of public policies on school inclusion, mainly those directed to the target audience of special education, the number of students with special educational needs in common classes has increased. This fact has helped to compose the picture in schools where the limitations and contradictions of the Brazilian educational system have appeared. Educational actors and authors are challenged to build knowledge able of responding to demands of daily school, concerning living and learning in diversity. Whereas this inclusive process is new in the schools, the study aimed to analyze the demands of teachers from the school inclusion. The research was qualitative and exploratory, and six teachers, their students with special educational needs and three professionals in the Nucleus of Inclusive Education from the Municipal Department of Education took in it. Technique of participant observation, field diary, semi-structured interview and questionnaire were used for data collection, while analysis of content was used for discussion of the data. The results indicate that there are achievements and contradictions in the reality of schools that themselves propose inclusive; advances and limitations resulting from the municipal politics; that the model of performance of the group of special education, in the context analyzed, may be revised or expanded; and that the teachers has demands with regard to public policy, training, and the psychologist.

  4. PREDICTING DEMAND FOR COTTON YARNS

    Directory of Open Access Journals (Sweden)

    SALAS-MOLINA Francisco

    2017-05-01

    Full Text Available Predicting demand for fashion products is crucial for textile manufacturers. In an attempt to both avoid out-of-stocks and minimize holding costs, different forecasting techniques are used by production managers. Both linear and non-linear time-series analysis techniques are suitable options for forecasting purposes. However, demand for fashion products presents a number of particular characteristics such as short life-cycles, short selling seasons, high impulse purchasing, high volatility, low predictability, tremendous product variety and a high number of stock-keeping-units. In this paper, we focus on predicting demand for cotton yarns using a non-linear forecasting technique that has been fruitfully used in many areas, namely, random forests. To this end, we first identify a number of explanatory variables to be used as a key input to forecasting using random forests. We consider explanatory variables usually labeled either as causal variables, when some correlation is expected between them and the forecasted variable, or as time-series features, when extracted from time-related attributes such as seasonality. Next, we evaluate the predictive power of each variable by means of out-of-sample accuracy measurement. We experiment on a real data set from a textile company in Spain. The numerical results show that simple time-series features present more predictive ability than other more sophisticated explanatory variables.

  5. Determining the Source of Water Vapor in a Cerium Oxide Electrochemical Oxygen Separator to Achieve Aviator Grade Oxygen

    Science.gov (United States)

    Graf, John; Taylor, Dale; Martinez, James

    2014-01-01

    More than a metric ton of water is transported to the International Space Station (ISS) each year to provide breathing oxygen for the astronauts. Water is a safe and compact form of stored oxygen. The water is electrolyzed on ISS and ambient pressure oxygen is delivered to the cabin. A much smaller amount of oxygen is used each year in spacesuits to conduct Extra Vehicular Activities (EVAs). Space suits need high pressure (>1000 psia) high purity oxygen (must meet Aviator Breathing Oxygen "ABO" specifications, >99.5% O2). The water / water electrolysis system cannot directly provide high pressure, high purity oxygen, so oxygen for EVAs is transported to ISS in high pressure gas tanks. The tanks are relatively large and heavy, and the majority of the system launch weight is for the tanks and not the oxygen. Extracting high purity oxygen from cabin air and mechanically compressing the oxygen might enable on-board production of EVA grade oxygen using the existing water / water electrolysis system. This capability might also benefit human spaceflight missions, where oxygen for EVAs could be stored in the form of water, and converted into high pressure oxygen on-demand. Cerium oxide solid electrolyte-based ion transport membranes have been shown to separate oxygen from air, and a supported monolithic wafer form of the CeO2 electrolyte membrane has been shown to deliver oxygen at pressures greater than 300 psia. These supported monolithic wafers can withstand high pressure differentials even though the membrane is very thin, because the ion transport membrane is supported on both sides (Fig 1). The monolithic supported wafers have six distinct layers, each with matched coefficients of thermal expansion. The wafers are assembled into a cell stack which allows easy air flow across the wafers, uniform current distribution, and uniform current density (Fig 2). The oxygen separation is reported to be "infinitely selective" to oxygen [1] with reported purity of 99.99% [2

  6. 46 CFR 169.689 - Demand loads.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Demand loads. 169.689 Section 169.689 Shipping COAST... Electrical Electrical Installations on Vessels of 100 Gross Tons and Over § 169.689 Demand loads. Demand loads must meet § 111.60-7 of this chapter except that smaller demand loads for motor feeders are...

  7. Dissolved oxygen and aeration in ictalurid catfish aquaculture

    Science.gov (United States)

    Feed-based production of ictalurid catfish in ponds is the largest aquaculture sector in the United States. The feed biochemical oxygen demand (FBOD) typically is 1.1-1.2 kg O2/kg feed. Feed also results in a substantial increase of carbon dioxide, ammonia nitrogen, and phosphate to ponds, and this ...

  8. Demand for food products in Finland: A demand system approach

    Directory of Open Access Journals (Sweden)

    Ilkka P. Laurila

    1994-07-01

    Full Text Available The study was concerned with the estimation of food-demand parameters in a system context. The patterns of food consumption in Finland were presented over the period 1950-1991, and a complete demand system of food expenditures was estimated. Price and expenditure elasticities of demand were derived, and the results were used to obtain projections on future consumption. While the real expenditure on food has increased, the budget share of food has decreased. In the early 19505, combined Food-at-Home and Food-away-from-Home corresponded to about 40% of consumers’ total expenditure. In 1991 the share was 28%. There was a shift to meals eaten outside the home. While the budget share of Food-away-from-Home increased from 3% to 7% over the observation period, Food-at-Home fell from 37% to 21%, and Food-at-Home excluding Alcoholic Drinks fell from 34% to 16%. Within Food-at-Home, the budget shares of the broad aggregate groups, Animalia (food from animal sources, Beverages, and Vegetablia (food from vegetable sources, remained about the same over the four decades, while structural change took place within the aggregates. Within Animalia, consumption shifted from Dairy Products (other than Fresh Milk to Meat and Fish. Within Beverages, consumption shifted from Fresh Milk and Hot Drinks to Alcoholic Drinks and Soft Drinks. Within Vegetablia, consumption shifted from Flour to Fruits, while the shares of Bread and Cake and Vegetables remained about the same. As the complete demand system, the Almost Ideal Demand System (AIDS was employed. The conventional AIDS was extended by developing a dynamic generalisation of the model and allowing for systematic shifts in structural relationships over time. A four-stage budgeting system was specified, consisting of seven sub-systems (groups, and covering 18 food categories. Tests on parameter restrictions and misspecification tests were used to choose the most preferred model specification for each group. Generally

  9. Closed Loop Control of Oxygen Delivery and Oxygen Generation

    Science.gov (United States)

    2017-08-01

    were used for this study and were connected via a USB cable to allow communication. The ventilator was modified to allow closed loop control of oxygen...connected via a USB cable to allow communication. The ventilator was modified to allow closed loop control of oxygen based on the oxygen saturation...2017-4119, 28 Aug 2017. oximetry (SpO2) and intermittent arterial blood sampling for arterial oxygen tension (partial pressure of oxygen [PaO2]) and

  10. Operational Limitations of Arctic Waste Stabilization Ponds: Insights from Modeling Oxygen Dynamics and Carbon Removal

    DEFF Research Database (Denmark)

    Ragush, Colin M.; Gentleman, Wendy C.; Hansen, Lisbeth Truelstrup

    2018-01-01

    Presented here is a mechanistic model of the biological dynamics of the photic zone of a single-cell arctic waste stabilization pond (WSP) for the prediction of oxygen concentration and the removal of oxygen-demanding substances. The model is an exploratory model to assess the limiting environmen...

  11. Photo-oxidation: Major sink of oxygen in the ocean surface layer

    NARCIS (Netherlands)

    Gieskes, W.W.C.; Laane, R.W.P.M.; Ruardij, P.

    2015-01-01

    Evidence is presented that the oxygen demand associated with photochemical processes in the surface layer of oceans and seas worldwide is of the same order of magnitude as the amount of oxygen released by photosynthesis of the world's marine phytoplankton. Both estimates are of necessity quite rough

  12. Photo-oxidation : Major sink of oxygen in the ocean surface layer

    NARCIS (Netherlands)

    Gieskes, W. W. C.; Laane, R. W. P. M.; Ruardij, P.

    2015-01-01

    Evidence is presented that the oxygen demand associated with photochemical processes in the surface layer of oceans and seas worldwide is of the same order of magnitude as the amount of oxygen released by photosynthesis of the world's marine phytoplankton. Both estimates are of necessity quite rough

  13. Market demands to Danish pork

    DEFF Research Database (Denmark)

    Bredahl, Lone

    2001-01-01

    position on its markets. It is expected that results of the analysis will be part of superior strategic decisions for the Danish pork sector as regards future Danish pork export markets. The market demands to be identified will therefore be evaluated in relation to resources and competences within the line...... of business. The study takes its starting point in a value chain perspective. The value chain covers the product- and distribution stages a product passes through before reaching the consumers. The value chain perspective presumes that added value is accumulated when a product passes through the stages...

  14. Uranium, resources, production and demand

    International Nuclear Information System (INIS)

    1990-01-01

    The thirteenth edition of the report looks at recent developments and their impact on the short term (i.e. to the year 2005) and presents a longer term (to 2030) analysis of supply possibilities in the context of a range of requirement scenarios. It presents results of a 1989 review of uranium supply and demand in the World Outside Centrally Planned Economies Areas. It contains updated information on uranium exploration activities, resources and production for over 40 countries including a few CPEs, covering the period 1987 and 1988

  15. Growing energy demand - environmental impact

    International Nuclear Information System (INIS)

    Rama Rao, G.A.

    2012-01-01

    Scientists can bring information, insights, and analytical skills to bear on matters of public concern. Often they can help the public and its representatives to understand the likely causes of events (such as natural and technological disasters) and to estimate the possible effects of projected policies. Often they can testify to what is not possible. Even so, scientists can seldom bring definitive answers to matters of public debate. Some issues are too complex to fit within the current scope of science, or there may be little reliable information available, or the values involved may lie outside of science. Scientists and technologists strive to find an answer to the growing energy demand

  16. LPG world supply and demand

    International Nuclear Information System (INIS)

    Holmes, Ch.

    2008-01-01

    Over the course of this decade, the global LPG market has moved from being tight, where supply barely exceeded non-price sensitive demand, to the current market situation where supply growth has outstripped demand growth to such an extent that current fundamentals suggest that considerable length will prevail in the market over the near term. As is the case for many other energy commodity markets, the LPG industry has experienced a considerable transformation over the last five years with many new LPG supply projects coming on-stream and demand growth in many developing markets slowing in response to higher energy prices. The near term challenge for LPG producers will be securing outlets for output as the market becomes increasingly oversupplied. With expanding LPG supply and a worldwide tightness in the naphtha market, it is expected that petrochemical consumers will favor relatively low priced LPG over naphtha and the resulting increase in LPG cracking rates will go some way to reducing the expected supply surplus. However, the timing of several new LPG supply projects and the start-up of LPG-based petrochemical plants in the Middle-East are expected to impact global LPG trade and pricing over the next few years. Thus, at this point in time, the global LPG market has a high degree of uncertainty with questions remaining over the impact of high energy (and LPG) prices on traditional and developing market demand, the timing of new supply projects and the combined effect of these two factors on international LPG prices. World LPG production has been rising in nearly every region of the world over the last few years and totaled about 229 million tons in 2007, which is some 30 million tons per year higher than in 2000. The exception is North America which accounts for the largest share of global LPG supply at about 24% but production there has remained relatively flat in recent years. Strong LPG production growth in the Middle-East which contributed to about 19% of

  17. World oil supply and demand'

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    Apart from a collapse of oil and gas consumption in the CIS, a strong increase in demand in the newly industrialized countries and an upward trend in the OECD countries are observed. Non-Opec supply continued to grow, with a production decline in Usa and Russia but a record production level in the North Sea and a remarkable revival in South America (Colombia, Argentina) and Africa (Congo, Angola). In Opec countries, the trend goes from supply control to development of production capacity. Situations in Saudi Arabia, Iran and Iraq are detailed

  18. Market architecture and power demand management

    International Nuclear Information System (INIS)

    Rious, Vincent; Roques, Fabien

    2014-12-01

    Demand response is a cornerstone problem in electricity markets considering climate change constraint. Most liberalized electricity markets have a poor track record at developing demand response. In Europe, different models are considered for demand response, from a development under a regulated regime to a development under competitive perspectives. In this paper, focusing on demand response for mid-size and small consumers, we investigate which types of market signals should be sent to demand response aggregators to see demand response emerge as a competitive activity. Using data from the French power system over eight years, we compare the possible market design options to allow demand response to develop. Our simulations demonstrate that with the current market rules, demand response is not a profitable activity in the French electricity industry. Introducing a capacity remuneration could bring additional revenues to demand response aggregators if the power system has no over-capacity

  19. Oxygen Dependent Biocatalytic Processes

    DEFF Research Database (Denmark)

    Pedersen, Asbjørn Toftgaard

    Enzyme catalysts have the potential to improve both the process economics and the environ-mental profile of many oxidation reactions especially in the fine- and specialty-chemical industry, due to their exquisite ability to perform stereo-, regio- and chemo-selective oxida-tions at ambient...... to aldehydes and ketones, oxyfunctionalization of C-H bonds, and epoxidation of C-C double bonds. Although oxygen dependent biocatalysis offers many possibilities, there are numerous chal-lenges to be overcome before an enzyme can be implemented in an industrial process. These challenges requires the combined...... far below their potential maximum catalytic rate at industrially relevant oxygen concentrations. Detailed knowledge of the en-zyme kinetics are therefore required in order to determine the best operating conditions and design oxygen supply to minimize processing costs. This is enabled...

  20. Two-photon NADH imaging exposes boundaries of oxygen diffusion in cortical vascular supply regions

    OpenAIRE

    Kasischke, Karl A; Lambert, Elton M; Panepento, Ben; Sun, Anita; Gelbard, Harris A; Burgess, Robert W; Foster, Thomas H; Nedergaard, Maiken

    2010-01-01

    Oxygen transport imposes a possible constraint on the brain's ability to sustain variable metabolic demands, but oxygen diffusion in the cerebral cortex has not yet been observed directly. We show that concurrent two-photon fluorescence imaging of endogenous nicotinamide adenine dinucleotide (NADH) and the cortical microcirculation exposes well-defined boundaries of tissue oxygen diffusion in the mouse cortex. The NADH fluorescence increases rapidly over a narrow, very low pO2 range with a p ...

  1. Hyperbaric oxygen and radiotherapy

    International Nuclear Information System (INIS)

    Mayer, R.; Hamilton-Farrell, M.R.; Kleij, A.J. van der

    2005-01-01

    Background: Hyperbaric oxygen (HBO) therapy is the inhalation of 100% oxygen at a pressure of at least 1.5 atmospheres absolute (150 kPa). It uses oxygen as a drug by dissolving it in the plasma and delivering it to the tissues independent of hemoglobin. For a variety of organ systems, HBO is known to promote new vessel growth into areas with reduced oxygen tension due to poor vascularity, and therewith promotes wound healing and recovery of radiation-injured tissue. Furthermore, tumors may be sensitized to irradiation by raising intratumoral oxygen tensions. Methods: A network of hyperbaric facilities exists in Europe, and a number of clinical studies are ongoing. The intergovernmental framework COST B14 action 'Hyperbaric Oxygen Therapy' started in 1999. The main goal of the Working Group Oncology is preparation and actual implementation of prospective study protocols in the field of HBO and radiation oncology in Europe. Results: In this paper a short overview on HBO is given and the following randomized clinical studies are presented: (a) reirradiation of recurrent squamous cell carcinoma of the head and neck after HBO sensitization; (b) role of HBO in enhancing radiosensitivity on glioblastoma multiforme; (c) osseointegration in irradiated patients; adjunctive HBO to prevent implant failures; (d) the role of HBO in the treatment of late irradiation sequelae in the pelvic region. The two radiosensitization protocols (a, b) allow a time interval between HBO and subsequent irradiation of 10-20 min. Conclusion: Recruitment of centers and patients is being strongly encouraged, detailed information is given on www.oxynet.org. (orig.)

  2. Diazonium Functionalisation of Carbon Nanotubes for Specific Orientation of Multicopper Oxidases: Controlling Electron Entry Points and Oxygen Diffusion to the Enzyme.

    Science.gov (United States)

    Lalaoui, Noémie; Holzinger, Michael; Le Goff, Alan; Cosnier, Serge

    2016-07-18

    We report the controlled orientation of bilirubin oxidases (BOD) from Myrothecium verrucaria on multiwalled carbon nanotubes (MWCNTs) functionalised by electrografting of 6-carboxynaphthalenediazonium and 4-(2-aminoethyl)benzenediazonium salts. On negatively charged naphthoate-modified MWCNTs, a high-potential (0.44 V vs. SCE) oxygen reduction electrocatalysis is observed, occurring via the T1 copper centre. On positively charged ammonium-modified MWCNTs, a low-potential (0.15 V) oxygen reduction electrocatalysis is observed, occurring through a partially oxidised state of the T2/T3 trinuclear copper cluster. Finally, chemically modified naphthoate MWCNTs exhibit high bioelectrocatalytic current densities of 3.9 mA cm(-2) under air at gas-diffusion electrode. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. [The oxygen consumption of ostrich embryos during incubation].

    Science.gov (United States)

    Reiner, G; Dzapo, V

    1995-02-01

    This work deals with the oxygen consumption of ostrich chicks during incubation. Brood eggs were incubated in a hermetic isolated acrylic-glass cylinder. Reduction of oxygen content in the air surrounding the egg was measured using an oxygen-sensitive electrode. A sigmoid curve could be drawn during incubation, with the steepest phase being around day 26. Maximum oxygen consumption was reached on day 36. It was slightly decreased until day 39, when the embryo switches to lung circulation, followed again by an increase until hatching. Average oxygen consumptions for the whole brood interval were calculated to 63.6 liters. Oxygen volumes consumed on day 36 result in a demand about to 240 liters of fresh air per egg and day. Oxygen consumption of the embryos on day 36 was significantly positive correlated with their vitality. Numb or less vital embryos could be clearly differentiated from others. The higher a chick's oxygen consumption, the earlier and shorter its hatching. Possible applications of the method in regard to the evaluation of incubation parameters or chicken constitution are discussed.

  4. Cerebral Microcirculation and Oxygen Tension in the Human Secondary Cortex

    Science.gov (United States)

    Linninger, A. A.; Gould, I. G.; Marinnan, T.; Hsu, C.-Y.; Chojecki, M.; Alaraj, A.

    2013-01-01

    The three-dimensional spatial arrangement of the cortical microcirculatory system is critical for understanding oxygen exchange between blood vessels and brain cells. A three-dimensional computer model of a 3 × 3 × 3 mm3 subsection of the human secondary cortex was constructed to quantify oxygen advection in the microcirculation, tissue oxygen perfusion, and consumption in the human cortex. This computer model accounts for all arterial, capillary and venous blood vessels of the cerebral microvascular bed as well as brain tissue occupying the extravascular space. Microvessels were assembled with optimization algorithms emulating angiogenic growth; a realistic capillary bed was built with space filling procedures. The extravascular tissue was modeled as a porous medium supplied with oxygen by advection–diffusion to match normal metabolic oxygen demand. The resulting synthetic computer generated network matches prior measured morphometrics and fractal patterns of the cortical microvasculature. This morphologically accurate, physiologically consistent, multi-scale computer network of the cerebral microcirculation predicts the oxygen exchange of cortical blood vessels with the surrounding gray matter. Oxygen tension subject to blood pressure and flow conditions were computed and validated for the blood as well as brain tissue. Oxygen gradients along arterioles, capillaries and veins agreed with in vivo trends observed recently in imaging studies within experimental tolerances and uncertainty. PMID:23842693

  5. Novel nanostructured oxygen sensor

    Science.gov (United States)

    Boardman, Alan James

    New government regulations and industry requirements for medical oxygen sensors require the development of alternate materials and process optimization of primary sensor components. Current oxygen sensors are not compliant with the Restriction of Hazardous Substances (RoHS) Directive. This work focused on two areas. First, was finding suitable readily available materials for the sensor anodes. Second was optimizing the processing of the sensor cathode membrane for reduced delamination. Oxygen sensors were made using tin (Sn) and bismuth (Bi) electrodes, potassium hydroxide (KOH) and acetic acid (CH3COOH) electrolytes with platinum (Pt) and gold (Au) reference electrodes. Bi electrodes were fabricated by casting and pressing processes. Electrochemical characterization of the Sn and Bi electrodes was performed by Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS) and sensing characterization per BSEN ISO 21647:2009 at various oxygen percentages, 0%, 20.9% and 100% oxygen levels with an automated test apparatus. The Sn anode with both electrolyte solutions showed good oxygen sensing properties and performance in a sensor. This system shows promise for replacement of Pb electrodes as required by the RoHS Directive. The Bi anode with Au cathode in both KOH and CH3COOH electrolytes showed acceptable performance and oxygen sensing properties. The Bi anodes fabricated by separate manufacturing methods demonstrated effectiveness for use in medical oxygen sensors. Gold thin films were prepared by magnetron sputtering on Flouroethylene Polymer (FEP) films. The FEP substrate temperature ranged from -77°C to 50°C. X-Ray Diffraction (XRD) and 4-point resistivity characterized the effects of substrate temperature to Au thin film particle size. XRD peak broadening and resistivity measurements showed a strong correlation of particle size to FEP substrate temperature. Particle size at 50°C was 594A and the -77°C particle size was 2.4 x 103A. Substrate

  6. Demand Response Valuation Frameworks Paper

    Energy Technology Data Exchange (ETDEWEB)

    Heffner, Grayson

    2009-02-01

    While there is general agreement that demand response (DR) is a valued component in a utility resource plan, there is a lack of consensus regarding how to value DR. Establishing the value of DR is a prerequisite to determining how much and what types of DR should be implemented, to which customers DR should be targeted, and a key determinant that drives the development of economically viable DR consumer technology. Most approaches for quantifying the value of DR focus on changes in utility system revenue requirements based on resource plans with and without DR. This ''utility centric'' approach does not assign any value to DR impacts that lower energy and capacity prices, improve reliability, lower system and network operating costs, produce better air quality, and provide improved customer choice and control. Proper valuation of these benefits requires a different basis for monetization. The review concludes that no single methodology today adequately captures the wide range of benefits and value potentially attributed to DR. To provide a more comprehensive valuation approach, current methods such as the Standard Practice Method (SPM) will most likely have to be supplemented with one or more alternative benefit-valuation approaches. This report provides an updated perspective on the DR valuation framework. It includes an introduction and four chapters that address the key elements of demand response valuation, a comprehensive literature review, and specific research recommendations.

  7. Economic demand and essential value.

    Science.gov (United States)

    Hursh, Steven R; Silberberg, Alan

    2008-01-01

    The strength of a rat's eating reflex correlates with hunger level when strength is measured by the response frequency that precedes eating (B. F. Skinner, 1932a, 1932b). On the basis of this finding, Skinner argued response frequency could index reflex strength. Subsequent work documented difficulties with this notion because responding was affected not only by the strengthening properties of the reinforcer but also by the rate-shaping effects of the schedule. This article obviates this problem by measuring strength via methods from behavioral economics. This approach uses demand curves to map how reinforcer consumption changes with changes in the "price" different ratio schedules impose. An exponential equation is used to model these demand curves. The value of this exponential's rate constant is used to scale the strength or essential value of a reinforcer, independent of the scalar dimensions of the reinforcer. Essential value determines the consumption level to be expected at particular prices and the response level that will occur to support that consumption. This approach permits comparing reinforcers that differ in kind, contributing toward the goal of scaling reinforcer value. (c) 2008 APA, all rights reserved

  8. Controlling energy demand. What history?

    International Nuclear Information System (INIS)

    Beers, Marloes; Bonhomme, Noel; Bouvier, Yves; Pautard, Eric; Fevrier, Patrick; Lanthier, Pierre; Goyens, Valerie; Desama, Claude; Beltran, Alain

    2012-01-01

    this special dossier of the historical annals of electricity collection takes stock of the post 1970's history of energy demand control in industrialized countries: Abatement of energy dependence, the European Communities program of rational use of energy in the 1970's (Marloes Beers); The G7 and the energy cost: the limits of dialogue between industrialized countries - 1975-1985 (Noel Bonhomme); Saving more to consume more. The ambiguity of EDF's communication during the 'energy saving' era (Yves Bouvier); From rationing to energy saving certificates, 4 decades of electricity demand control in France and in the UK (eric Pautard); The French agency of environment and energy mastery (ADEME): between energy control and sustainable development (Patrick Fevrier); Hydro-Quebec and efficiency in household energy consumption, from 1990 to the present day (Pierre Lanthier); Control of energy consumption since the 1970's, the policy of rational use of energy in Walloon region - Belgium (Valerie Goyens); Electricity distribution in the new energy paradigm (Claude Desama); Conclusion (Alain Beltran)

  9. OXYGEN MANAGEMENT DURING ALCOHOLIC FERMENTATION

    OpenAIRE

    MOENNE VARGAS, MARÍA ISABE

    2013-01-01

    Oxygen additions are a common practice in winemaking, as oxygen has a positive effect in fermentative kinetics, biomass synthesis and improvement of color, structure and :flavor in treated wines. However, most oxygen additions are carried out heuristically through pump-over operations solely on a know-how basis, which is difficult to manage in terms of the exact quantity of oxygen transferred to the fermenting must. It is important to estímate the amount of oxygen added because...

  10. Eta Carinae: A Demanding Mistress

    Science.gov (United States)

    Gull, Theodore

    2012-01-01

    In the 1840's a southern star, Eta Argus, brightened to rival Sirius for nearly a decade, then faded. Today, we see the Homunculus, an hourglass figure with tutu, a dusty shell exceeding 12 solar masses expanding outward at 500 km/s. Many observers have systematically studied the massive binary total shrouded by interacting winds and its ejecta. More recently 3-D wind-wind collision models have begun to explain the extended structures resolved by Hubble Space Telescope. Now Herschel Space Observatory infrared scans are revealing wind interaction emissions and complex molecules left over from the dust that formed out of gas originally overabundant in nitrogen and greatly-depleted in oxygen and carbon. Many questions remain to be answered: What is the dust that formed in the 1840s event? What are the end states of the two massive companions ... SN, GRB, Hypernova? and When

  11. Optic nerve oxygen tension

    DEFF Research Database (Denmark)

    Kiilgaard, Jens Folke; Pedersen, D B; Eysteinsson, T

    2004-01-01

    The authors have previously reported that carbonic anhydrase inhibitors such as acetazolamide and dorzolamide raise optic nerve oxygen tension (ONPO(2)) in pigs. The purpose of the present study was to investigate whether timolol, which belongs to another group of glaucoma drugs called beta...

  12. Home Oxygen Therapy

    Science.gov (United States)

    ... cold it can hurt your skin. Keep a fire extinguisher close by, and let your fire department know that you have oxygen in your ... any symptoms of illness. Medicare, Medicaid, and Commercial Insurance Certain insurance policies may pay for all your ...

  13. Central oxygen pipeline failure

    African Journals Online (AJOL)

    surgical intensive care unit (ICU), with two patients on full ventilation and ... uncertainty around the cause of the failure and the restoration, .... soon as its level also falls below three tons. Should ... (properly checked and closed prior to each anaesthetic). ... in use at the time of the central oxygen pipeline failure at Tygerberg.

  14. Extracorporeal membrane oxygenation (ECMO)

    African Journals Online (AJOL)

    Extracorporeal membrane oxygenation (ECMO) is not a novel therapy in the true sense of the ... Intention-to-treat analysis showed benefit for ECMO, with a relative risk ... no doubt that VV-ECMO is an advance in medical technology, and that.

  15. Oxygen Extraction from Minerals

    Science.gov (United States)

    Muscatello, Tony

    2017-01-01

    Oxygen, whether used as part of rocket bipropellant or for astronaut life support, is a key consumable for space exploration and commercialization. In Situ Resource Utilization (ISRU) has been proposed many times as a method for making space exploration more cost effective and sustainable. On planetary and asteroid surfaces the presence of minerals in the regolith that contain oxygen is very common, making them a potential oxygen resource. The majority of research and development for oxygen extraction from minerals has been for lunar regolith although this work would generally be applicable to regolith at other locations in space. This presentation will briefly survey the major methods investigated for oxygen extraction from regolith with a focus on the current status of those methods and possible future development pathways. The major oxygen production methods are (1) extraction from lunar ilmenite (FeTiO3) with either hydrogen or carbon monoxide, (2) carbothermal reduction of iron oxides and silicates with methane, and (3) molten regolith electrolysis (MRE) of silicates. Methods (1) and (2) have also been investigated in a two-step process using CO reduction and carbon deposition followed by carbothermal reduction. All three processes have byproducts that could also be used as resources. Hydrogen or carbon monoxide reduction produce iron metal in small amounts that could potentially be used as construction material. Carbothermal reduction also makes iron metal along with silicon metal and a glass with possible applications. MRE produces iron, silicon, aluminum, titanium, and glass, with higher silicon yields than carbothermal reduction. On Mars and possibly on some moons and asteroids, water is present in the form of mineral hydrates, hydroxyl (-OH) groups on minerals, andor water adsorbed on mineral surfaces. Heating of the minerals can liberate the water which can be electrolyzed to provide a source of oxygen as well. The chemistry of these processes, some key

  16. Ocean Ridges and Oxygen

    Science.gov (United States)

    Langmuir, C. H.

    2014-12-01

    The history of oxygen and the fluxes and feedbacks that lead to its evolution through time remain poorly constrained. It is not clear whether oxygen has had discrete steady state levels at different times in Earth's history, or whether oxygen evolution is more progressive, with trigger points that lead to discrete changes in markers such as mass independent sulfur isotopes. Whatever this history may have been, ocean ridges play an important and poorly recognized part in the overall mass balance of oxidants and reductants that contribute to electron mass balance and the oxygen budget. One example is the current steady state O2 in the atmosphere. The carbon isotope data suggest that the fraction of carbon has increased in the Phanerozoic, and CO2 outgassing followed by organic matter burial should continually supply more O2 to the surface reservoirs. Why is O2 not then increasing? A traditional answer to this question would relate to variations in the fraction of burial of organic matter, but this fraction appears to have been relatively high throughout the Phanerozoic. Furthermore, subduction of carbon in the 1/5 organic/carbonate proportions would contribute further to an increasingly oxidized surface. What is needed is a flux of oxidized material out of the system. One solution would be a modern oxidized flux to the mantle. The current outgassing flux of CO2 is ~3.4*1012 moles per year. If 20% of that becomes stored organic carbon, that is a flux of .68*1012 moles per year of reduced carbon. The current flux of oxidized iron in subducting ocean crust is ~2*1012 moles per year of O2 equivalents, based on the Fe3+/Fe2+ ratios in old ocean crust compared to fresh basalts at the ridge axis. This flux more than accounts for the incremental oxidizing power produced by modern life. It also suggests a possible feedback through oxygenation of the ocean. A reduced deep ocean would inhibit oxidation of ocean crust, in which case there would be no subduction flux of oxidized

  17. Demand Moderation in Military Communication Networks

    National Research Council Canada - National Science Library

    Blackmore, Perry

    2002-01-01

    .... Demand moderation is the term used to encompass the array of mechanisms aimed at achieving this end. Integrated Defence networks of the future should benefit enormously from demand moderation mechanisms.

  18. Demand sensing in e-business

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Accurate assessment of demand and market shares is critical for many businesses and public ... allowing them to reap much higher benefits from demand sensing. .... entiation in service policies that offers a cost-effective compromise between ...

  19. Mobility on Demand Operational Concept Report.

    Science.gov (United States)

    2017-09-10

    This operational concept report provides an overview of the Mobility on Demand (MOD) concept and its evolution, description of the MOD ecosystem in a supply and demand framework, and its stakeholders and enablers. Leveraging the MOD ecosystem framewo...

  20. Driving demand for broadband networks and services

    CERN Document Server

    Katz, Raul L

    2014-01-01

    This book examines the reasons why various groups around the world choose not to adopt broadband services and evaluates strategies to stimulate the demand that will lead to increased broadband use. It introduces readers to the benefits of higher adoption rates while examining the progress that developed and emerging countries have made in stimulating broadband demand. By relying on concepts such as a supply and demand gap, broadband price elasticity, and demand promotion, this book explains differences between the fixed and mobile broadband demand gap, introducing the notions of substitution and complementarity between both platforms. Building on these concepts, ‘Driving Demand for Broadband Networks and Services’ offers a set of best practices and recommendations aimed at promoting broadband demand.  The broadband demand gap is defined as individuals and households that could buy a broadband subscription because they live in areas served by telecommunications carriers but do not do so because of either ...

  1. Demands Set Upon Modern Cartographic Visualization

    Directory of Open Access Journals (Sweden)

    Stanislav Frangeš

    2007-05-01

    Full Text Available Scientific cartography has the task to develop and research new methods of cartographic visualization. General demands are set upon modern cartographic visualization, which encompasses digital cartography and computer graphics: legibility, clearness, accuracy, plainness and aesthetics. In this paper, it is explained in detail what demands should be met in order to satisfy the general demands set. In order to satisfy the demand of legibility, one should respect conditions of minimal sizes, appropriate graphical density and better differentiation of known features. Demand of clearness needs to be met by fulfilling conditions of simplicity, contrasting quality and layer arrangement of cartographic representation. Accuracy, as the demand on cartographic visualization, can be divided into positioning accuracy and accuracy signs. For fulfilling the demand of plainness, the conditions of symbolism, traditionalism and hierarchic organization should be met. Demand of aesthetics will be met if the conditions of beauty and harmony are fulfilled.

  2. Cut Electric Bills by Controlling Demand

    Science.gov (United States)

    Grumman, David L.

    1974-01-01

    Electric bills can be reduced by lowering electric consumption and by controlling demand -- the amount of electricity used at a certain point in time. Gives tips to help reduce electric demand at peak power periods. (Author/DN)

  3. Prices dip on slow demand

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    The Restricted Uranium Spot Market Price Range slipped to $9.90-$10.35, mostly due to lackluster demand. Only three transactions took place during the month. Two of the purchases, accounting for 98% of the month's volume, were by European utilities; the other was made by a US utility. One of the European purchases was made in the unrestricted market, but since it included a host of fuel cycle services, the U3O8 price could not be determined. Hence, NUKEM's Unrestricted Uranium Spot Market Price Range stays the same, at $7.90-$8.00. The other European deal, concluded in the restricted market, represents the low end of the restricted market price range. The US deal was based on bids that were made at the beginning of November and therefore does not reflect market conditions in December. Looking ahead, we see four utilities ready to enter the market for nearly 1 million lbs U3O8 equivalent

  4. Residential electricity demand in Singapore

    International Nuclear Information System (INIS)

    Ang, B.W.; Goh, T.N.; Liu, X.Q.

    1992-01-01

    Residential electricity consumption in Singapore increased at a rate of 8.8% per year between 1972 and 1990. Estimates of the long-run income and price elasticities are 1.0 and -0.35, respectively. The energy-conservation campaigns that have been launched are found to have marginal effects on consumption. A statistical analysis shows that the consumption is sensitive to small changes in climatic variables, particularly the temperature, which is closely linked to the growing diffusion of electric appliances for environmental controls. There has been a temporal increase in the ownership levels of appliances associated with increasing household incomes. However, other factors were involved since the ownership levels would also increase over time after the elimination of the income effect. A large part of the future growth in electricity demand will arise from the growing need for air-conditioning, which will lead to increasingly large seasonal variations in electricity use. (author)

  5. Uranium, resources, production and demand

    International Nuclear Information System (INIS)

    1986-01-01

    Periodic assessments of world uranium supply have been conducted by the OECD Nuclear Energy Agency (NEA) and the International Atomic Energy Agency (IAEA) since the mid 1960s. Published every two years, the report Uranium resources, production and demand, commonly referred to as the red book, has become an essential reference document for nuclear planners and policy makers in the international nuclear community. The latest red book, published in 1986, was based on data collected mainly in early 1985. Most of the data for 1985 were therefore provisional. The statistical update 1986 provides updated 1985 data collected in 1986 and provisional data for 1986. This is the first time such an annual update of key Red Book statistical data has been prepared. This year it covers only OECD countries with a secretariat estimate for the rest of Woca

  6. Transport gasoline demand in Canada

    International Nuclear Information System (INIS)

    Eltony, M.N.

    1993-01-01

    This paper provides an estimate of household gasoline demand in Canada by applying a detailed model to pool time-series (1969-1988) and cross-sectional provincial data. The model recognises three major behavioural changes that households can make in response to gasoline price changes: drive fewer miles, purchase fewer cars, and buy more fuel-efficient vehicles. In the model, fuel economy is treated in considerable detail. The two components of the fuel economy of new cars sold-the technical fuel efficiency of various classes of cars and the distribution of new car sales according to their interior volume rather than their weight - are estimated as functions of economic variables. Car manufacturers are assumed to improve the technical fuel economy according to their expectation of consumer's response to future changes in gasoline prices and general economic conditions. (author)

  7. Matching energy sources to demand

    International Nuclear Information System (INIS)

    Hendry, A.

    1979-01-01

    Diagrams show the current pattern of energy usage in Scotland; primary energy inputs; the various classes of user; the disposition of input energy in terms of useful and waste energy; an energy flow diagram showing the proportions of primary fuels taken by the various user groups and the proportions of useful energy derived by each. Within the S.S.E.B. area, installed capacity and maximum demand are shown for the present and projected future to the year 2000. A possible energy flow diagram for Scotland in 1996 is shown. The more efficient use of energy is discussed, with particular reference to the use of electricity. The primary energy inputs considered are oil, coal, nuclear, hydro and gas. (U.K.)

  8. Oxygen diffusion in monazite

    Science.gov (United States)

    Cherniak, D. J.; Zhang, X. Y.; Nakamura, M.; Watson, E. B.

    2004-09-01

    We report measurements of oxygen diffusion in natural monazites under both dry, 1-atm conditions and hydrothermal conditions. For dry experiments, 18O-enriched CePO4 powder and monazite crystals were sealed in Ag-Pd capsules with a solid buffer (to buffer at NNO) and annealed in 1-atm furnaces. Hydrothermal runs were conducted in cold-seal pressure vessels, where monazite grains were encapsulated with 18O-enriched water. Following the diffusion anneals, oxygen concentration profiles were measured with Nuclear Reaction Analysis (NRA) using the reaction 18O(p,α)15N. Over the temperature range 850-1100 °C, the Arrhenius relation determined for dry diffusion experiments on monazite is given by: Under wet conditions at 100 MPa water pressure, over the temperature range 700-880 °C, oxygen diffusion can be described by the Arrhenius relationship: Oxygen diffusion under hydrothermal conditions has a significantly lower activation energy for diffusion than under dry conditions, as has been found the case for many other minerals, both silicate and nonsilicate. Given these differences in activation energies, the differences between dry and wet diffusion rates increase with lower temperatures; for example, at 600 °C, dry diffusion will be more than 4 orders of magnitude slower than diffusion under hydrothermal conditions. These disparate diffusivities will result in pronounced differences in the degree of retentivity of oxygen isotope signatures. For instance, under dry conditions (presumably rare in the crust) and high lower-crustal temperatures (∼800 °C), monazite cores of 70-μm radii will preserve O isotope ratios for about 500,000 years; by comparison, they would be retained at this temperature under wet conditions for about 15,000 years.

  9. Controlled manipulation of oxygen vacancies using nanoscale flexoelectricity

    Energy Technology Data Exchange (ETDEWEB)

    Das, Saikat [Inst. for Basic Science (IBS), Seoul (Republic of Korea). Center for Correlated Electron Systems; Seoul National University (SNU), Seoul (Republic of Korea). Dept. of Physics and Astronomy; Wang, Bo [Pennsylvania State Univ., University Park, PA (United States).Dept. of Materials Science and Engineering; Cao, Ye [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Inst. for; Rae Cho, Myung [Inst. for Basic Science (IBS), Seoul (Republic of Korea). Center for Correlated Electron Systems; Seoul National University (SNU), Seoul (Republic of Korea). Dept. of Physics and Astronomy; Jae Shin, Yeong [Inst. for Basic Science (IBS), Seoul (Republic of Korea). Center for Correlated Electron Systems; Seoul National University (SNU), Seoul (Republic of Korea). Dept. of Physics and Astronomy; Mo Yang, Sang [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS); Sookmyung Women' s Univ., Seoul (Republic of Korea). Dept. of Physics; Wang, Lingfei [Inst. for Basic Science (IBS), Seoul (Republic of Korea). Center for Correlated Electron Systems; Seoul National University (SNU), Seoul (Republic of Korea). Dept. of Physics and Astronomy; Kim, Minu [Inst. for Basic Science (IBS), Seoul (Republic of Korea). Center for Correlated Electron Systems; Seoul National University (SNU), Seoul (Republic of Korea). Dept. of Physics and Astronomy; Kalinin, Sergei V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Inst. for Functional Imaging of Materials; Chen, Long-Qing [Pennsylvania State Univ., University Park, PA (United States).Dept. of Materials Science and Engineering; Noh, Tae Won [Inst. for Basic Science (IBS), Seoul (Republic of Korea). Center for Correlated Electron Systems; Seoul National University (SNU), Seoul (Republic of Korea). Dept. of Physics and Astronomy

    2017-09-20

    Oxygen vacancies, especially their distribution, are directly coupled to the electromagnetic properties of oxides and related emergent functionalities that have implications for device applications. Here using a homoepitaxial strontium titanate thin film, we demonstrate a controlled manipulation of the oxygen vacancy distribution using the mechanical force from a scanning probe microscope tip. By combining Kelvin probe force microscopy imaging and phase-field simulations, we show that oxygen vacancies can move under a stress-gradient-induced depolarisation field. When tailored, this nanoscale flexoelectric effect enables a controlled spatial modulation. In motion, the scanning probe tip thereby deterministically reconfigures the spatial distribution of vacancies. Finally, the ability to locally manipulate oxygen vacancies on-demand provides a tool for the exploration of mesoscale quantum phenomena and engineering multifunctional oxide devices.

  10. Brain magnetic resonance imaging with contrast dependent on blood oxygenation

    International Nuclear Information System (INIS)

    Ogawa, S.; Lee, T.M.; Kay, A.R.; Tank, D.W.

    1990-01-01

    Paramagnetic deoxyhemoglobin in venous blood is a naturally occurring contrast agent for magnetic resonance imaging (MRI). By accentuating the effects of this agent through the use of gradient-echo techniques in high yields, the authors demonstrate in vivo images of brain microvasculature with image contrast reflecting the blood oxygen level. This blood oxygenation level-dependent (BOLD) contrast follows blood oxygen changes induced by anesthetics, by insulin-induced hypoglycemia, and by inhaled gas mixtures that alter metabolic demand or blood flow. The results suggest that BOLD contrast can be used to provide in vivo real-time maps of blood oxygenation in the brain under normal physiological conditions. BOLD contrast adds an additional feature to magnetic resonance imaging and complement other techniques that are attempting to provide position emission tomography-like measurements related to regional neural activity

  11. Crude oil prices: Robust demands strengthens outlook

    International Nuclear Information System (INIS)

    Simmons, M.R.

    1996-01-01

    This paper briefly summarizes the growth in the global demand for oil products by showing the historical trends in production and demand in developing countries. It shows world incremental production growth from 1985 to 1995 and developing countries's demands from 1971 to 1989. The paper goes on to make predictions as to whether the demand growth rate can be sustained. It provides information on the status of the world offshore drilling and production facilities to determine the capacity of this resource

  12. Price elasticity of demand: An overlooked concept

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    An all-too-common mistake in analyzing the uranium market is to assume that demand for uranium is driven only by the design and operational parameters of nuclear power plants. Because it is generally accepted that demand for uranium is inelastic, not much attention has been given to how prices can indirectly affect demand. The purpose of this paper is to highlight the factors that are most sensitive to uranium prices, and to show how they alter uranium demand

  13. Endogenous Money Supply and Money Demand

    OpenAIRE

    Woon Gyu Choi; Seonghwan Oh

    2000-01-01

    This paper explores the behavior of money demand by explicitly accounting for the money supply endogeneity arising from endogenous monetary policy and financial innovations. Our theoretical analysis indicates that money supply factors matter in the money demand function when the money supply partially responds to money demand. Our empirical results with U.S. data provide strong evidence for the relevance of the policy stance to the demand for MI under a regime in which monetary policy is subs...

  14. Water demand management in Mediterranean regions

    OpenAIRE

    Giulio Querini; Salvo Creaco

    2005-01-01

    Water sustainability needs a balance between demand and availability: 1) Water demand management: demand may be managed by suppliers and regulations responsible persons, using measures like invoicing, consumptions measurement and users education in water conservation measures; 2) Augmentation of water supply: availibility may be augmented by infrastructural measures, waste water reuse, non-conventional resources and losses reduction. Water Demand Management is about achieving a reduction in t...

  15. 7 CFR 987.11 - Trade demand.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Trade demand. 987.11 Section 987.11 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... RIVERSIDE COUNTY, CALIFORNIA Order Regulating Handling Definitions § 987.11 Trade demand. Trade demand means...

  16. 31 CFR 29.511 - Demand letters.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Demand letters. 29.511 Section 29.511... Overpayments § 29.511 Demand letters. Except as provided in § 29.516(e), before starting collection action to recover an overpayment, the Benefits Administrator must send a demand letter that informs the debtor in...

  17. 7 CFR 981.21 - Trade demand.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Trade demand. 981.21 Section 981.21 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 981.21 Trade demand. Trade demand means the quantity of almonds...

  18. 7 CFR 3560.709 - Demand letter.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Demand letter. 3560.709 Section 3560.709 Agriculture... DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Unauthorized Assistance § 3560.709 Demand letter. (a) If a... repayment schedule, the Agency will send the borrower a demand letter specifying: (1) The amount of...

  19. Oil prices: demand and supply. Lesson plan

    OpenAIRE

    anonymous

    2005-01-01

    Upon completion of this lesson, students will be able to list the determinants of demand and supply, recognize which factors will cause demand curves or supply curves to shift, determine equilibrium using a demand/supply graph, and show the effects on price and quantity when equilibrium changes.

  20. Detecting pipe bursts by monitoring water demand

    NARCIS (Netherlands)

    Bakker, M.; Vreeburg, J.H.G.; Van der Roer, M.; Sperber, V.

    2012-01-01

    An algorithm which compares measured and predicted water demands to detect pipe bursts was developed and tested on three data sets of water demand and reported pipe bursts of three years. The algorithm proved to be able to detect bursts where the water loss exceeds 30% of the average water demand in

  1. Effect of abattoir wastes on the water quality of Aleto River in the ...

    African Journals Online (AJOL)

    The effects of abattoir effluent on the water quality parameters, pH, dissolved oxygen, nitrate (NO3), phosphate (PO4), sulphate (SO4), hardness, conductivity, faecal coliform and the biochemical oxygen demand (BOD), of the receiving surface water of Aleto River in River State (Niger Delta, Nigeria) was monitored monthly ...

  2. Exploring Demand Charge Savings from Commercial Solar

    Energy Technology Data Exchange (ETDEWEB)

    Darghouth, Naim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Gagnon, Pieter [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bird, Lori [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-07-31

    Commercial retail electricity rates commonly include a demand charge component, based on some measure of the customer’s peak demand. Customer-sited solar PV can potentially reduce demand charges, but the magnitude of these savings can be difficult to predict, given variations in demand charge designs, customer loads, and PV generation profiles. Moreover, depending on the circumstances, demand charges from solar may or may not align well with associated utility cost savings. Lawrence Berkeley National Laboratory (Berkeley Lab) and the National Renewable Energy Laboratory (NREL) are collaborating in a series of studies to understand how solar PV can reduce demand charge levels for a variety of customer types and demand charges designs. Previous work focused on residential customs with solar. This study, instead, focuses on commercial customers and seeks to understand the extent and conditions under which rooftop can solar reduce commercial demand charges. To answer these questions, we simulate demand charge savings for a broad range of commercial customer types, demand charge designs, locations, and PV system characteristics. This particular analysis does not include storage, but a subsequent analysis in this series will evaluate demand charge savings for commercial customers with solar and storage.

  3. Origin of photosynthetic oxygen

    International Nuclear Information System (INIS)

    Gerster, Richard; Dupuy, Jacques; Guerin de Montgareuil, Pierre

    From the comparison of isotopic exchange kinetics between C 18 O 2 and the water of algae suspensions or aerial leaves subjected to alternating darkness and light, it becomes possible to calculate the isotopic abundance of the CO 2 involved in the photochemical process; this value has been compared to those of the intracellular water and of the evolved O 2 . Kinetics of the appearance of 18 O in the oxygen produced by algae suspended in enriched water are also presented [fr

  4. Untitled

    African Journals Online (AJOL)

    surface-water problem, affecting both which is the main tributary of the River running and still water demanding special. Gibe. Such waste discharge without any attention (2). form of treatment not only becomes a. The 5-day Biological Oxygen. Demand (BOD) is the best single strength potential health hazard to the nearby.

  5. Evaluation of selected wetland plants for removal of chromium from ...

    African Journals Online (AJOL)

    user

    demand (COD), biochemical oxygen demand (BOD) and nitrogen under a 5 day hydraulic retention time were analyzed based on HACH manual. The Cr in the plant tissue was analyzed through .... measured for five days of hydraulic retention time (HRT) using a stopwatch and measuring cylinder (Figure 1). The wastewater ...

  6. Crucial market demands and company competencies

    DEFF Research Database (Denmark)

    Jensen, Bjarne; Stacey, Julia

    1999-01-01

    More and more, it is acknowledged that a company's success depends on it being capable of complying with the market's demands and wishes. It is, however, not always obvious, how the individual company will be able to meet the market's demands. A recent MAPP study has investigated this topic...... and identified a number of central market demands, which Danish food companies are faced with. Moreover, the study has identified which competencies are required to meet these demands and have also looked at howsuccessful companies structure some of these competencies. The study takes its point of departure...... in a literature review of MAPP's research. Results show that there are 27 central market demands, retail and consumer demands that Danish companies ought to be able to live up to. The study has also identified which competencies food companies must possess to be able to meet market's demands. Results from three...

  7. Demand Uncertainty: Exporting Delays and Exporting Failures

    DEFF Research Database (Denmark)

    Nguyen, Daniel Xuyen

    2012-01-01

    This paper presents a model of trade that explains why firms wait to export and why many exporters fail. Firms face uncertain demands that are only realized after the firm enters the destination. The model retools the timing of the resolution of uncertainty found in models with heterogeneity...... of firm productivity. This retooling addresses several shortcomings. First, the imperfect correlation of demands reconciles the sales variation observed in and across destinations. Second, since demands for the firm's output are correlated across destinations, a firm can use previously realized demands...... to forecast unknown demands in untested destinations. The option to forecast demands causes firms to delay exporting in order to gather more information about foreign demand. Third, since uncertainty is resolved after entry, many firms enter a destination and then exit after learning that they cannot profit...

  8. Food safety information and food demand

    DEFF Research Database (Denmark)

    Smed, Sinne; Jensen, Jørgen Dejgård

    2005-01-01

    Purpose – The purpose of this paper is to analyze how news about food-related health risks affects consumers’ demands for safe food products. Design/methodology/approach – By identifying structural breaks in an econometrically estimated demand model, news with permanent impact on demand...... induces a permanent increase in the demand for pasteurized eggs, while more moderate negative news influences demand temporarily and to a lesser extent. There is, however, considerable variation in the response to food safety news across socio-demographic groups of consumers. Research limitations...... is distinguished from news with temporary impact. The Danish demand for pasteurized versus shell eggs is used as an illustrative case. Findings – Negative safety news about one product variety can provide significant stimulation to the demand for safe varieties. Severe negative news about the safety of shell eggs...

  9. Stability of Money Demand Function in Pakistan

    Directory of Open Access Journals (Sweden)

    Haroon Sarwar

    2013-09-01

    Full Text Available The role, which money demand function plays in monetary policy formulation has attracted a lot of research studies to analyze this macroeconomic phenomenon. In the wake of current global and local economic and political upheavals, it is imperative to revisit the stability of money demand function. The study used the time series data and applied latest econometric techniques to find out the long run and short run money demand relationship. Moreover, all the three official monetary aggregates were used for finding out the most stable monetary demand relationship, which could provide correct signals for monetary policy formulation. The study found that broader monetary aggregate (M2 was the proper aggregate, which provided stable money demand function for Pakistan. The real GDP was positively related to the demand for real balances, while opportunity cost of money was negatively related. The study found that the role of financial innovation, in explaining the demand for money warrants attention in formulating monetary policy.

  10. Oxygen injection facility

    International Nuclear Information System (INIS)

    Ota, Masamoto; Hirose, Yuki

    1998-01-01

    A compressor introduces air as a starting material and sends it to a dust removing device, a dehumidifying device and an adsorption/separation system disposed downstream. The facility of the present invention is disposed in the vicinity of an injection point and installed in a turbine building of a BWR type reactor having a pipeline of a feedwater system to be injected. The adsorbing/separation system comprises an adsorbing vessel and an automatic valve, and the adsorbing vessel is filled with an adsorbent for selectively adsorbing nitrogen. Zeolite is used as the adsorbent. Nitrogen in the air passing through the adsorbing vessel is adsorbed and removed under a pressurized condition, and a highly concentrated oxygen gas is formed. The direction of the steam of the adsorbed nitrogen is changed by an opening/closing switching operation of an automatic valve and released to the atmosphere (the pressure is released). Generated oxygen gas is stored under pressure in a tank, and injected to the pipeline of the feedwater system by an oxygen injection conduit by way of a flow rate control valve. In the adsorbing vessel, steps of adsorption, separation and storage under pressure are repeated successively. (I.N.)

  11. ITM oxygen for gasification

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, P.A.; Foster, E.P. [Air Products and Chemicals Inc., Toronto, ON (Canada); Gunardson, H.H. [Air Products Canada Ltd., Mississauga, ON (Canada)

    2005-11-01

    This paper described a newly developed air separation technology called Ionic Transport Membrane (ITM), which reduces the overall cost of the gasification process. The technology is well suited for advanced energy conversion processes such as integrated gasification combined cycle (IGCC) that require oxygen and use heavy carbonaceous feedstocks such as residual oils, bitumens, coke and coal. It is also well suited for traditional industrial applications for oxygen and distributed power. Air Products Canada Limited developed the ceramic membrane air separation technology that can reduce the cost of pure oxygen by more than 30 per cent. The separation technology achieves a capital cost reduction of 30 per cent and an energy reduction of 35 per cent over conventional cryogenic air separation. ITM is an electrochemical process that integrates well with the gasification process and an IGCC option for producing electricity from the waste heat generated from gasification. This paper described the integration of ITM technology with both the gasification and IGCC processes and showed the attractive economics of ITM. 6 refs., 2 tabs., 6 figs.

  12. Worldwide satellite market demand forecast

    Science.gov (United States)

    Bowyer, J. M.; Frankfort, M.; Steinnagel, K. M.

    1981-01-01

    The forecast is for the years 1981 - 2000 with benchmark years at 1985, 1990 and 2000. Two typs of markets are considered for this study: Hardware (worldwide total) - satellites, earth stations and control facilities (includes replacements and spares); and non-hardware (addressable by U.S. industry) - planning, launch, turnkey systems and operations. These markets were examined for the INTELSAT System (international systems and domestic and regional systems using leased transponders) and domestic and regional systems. Forecasts were determined for six worldwide regions encompassing 185 countries using actual costs for existing equipment and engineering estimates of costs for advanced systems. Most likely (conservative growth rate estimates) and optimistic (mid range growth rate estimates) scenarios were employed for arriving at the forecasts which are presented in constant 1980 U.S. dollars. The worldwide satellite market demand forecast predicts that the market between 181 and 2000 will range from $35 to $50 billion. Approximately one-half of the world market, $16 to $20 billion, will be generated in the United States.

  13. The Integron: Adaptation On Demand.

    Science.gov (United States)

    Escudero, José Antonio; Loot, Céline; Nivina, Aleksandra; Mazel, Didier

    2015-04-01

    The integron is a powerful system which, by capturing, stockpiling, and rearranging new functions carried by gene encoding cassettes, confers upon bacteria a rapid adaptation capability in changing environments. Chromosomally located integrons (CI) have been identified in a large number of environmental Gram-negative bacteria. Integron evolutionary history suggests that these sedentary CIs acquired mobility among bacterial species through their association with transposable elements and conjugative plasmids. As a result of massive antibiotic use, these so-called mobile integrons are now widespread in clinically relevant bacteria and are considered to be the principal agent in the emergence and rise of antibiotic multiresistance in Gram-negative bacteria. Cassette rearrangements are catalyzed by the integron integrase, a site-specific tyrosine recombinase. Central to these reactions is the single-stranded DNA nature of one of the recombination partners, the attC site. This makes the integron a unique recombination system. This review describes the current knowledge on this atypical recombination mechanism, its implications in the reactions involving the different types of sites, attC and attI, and focuses on the tight regulation exerted by the host on integron activity through the control of attC site folding. Furthermore, cassette and integrase expression are also highly controlled by host regulatory networks and the bacterial stress (SOS) response. These intimate connections to the host make the integron a genetically stable and efficient system, granting the bacteria a low cost, highly adaptive evolution potential "on demand".

  14. Nuclear Knowledge - Demand or Pride?

    International Nuclear Information System (INIS)

    Valeca, S.C.; Valeca, M.

    2009-01-01

    Full text: Nowadays, the increasing energy demand and the decreasing 'classical' resources is a reality. In this context, sustainable development and economical growth is mandatory for each country. Nuclear energy becomes more and more attractive in order to solve those problems. During last years, nuclear knowledge management became an interesting topic in dedicated debates, due to the uniqueness of nuclear Industry. With five decades of operational experience in commercial power production, the nuclear power industry is mature and represents the first high technology enterprise of the twentieth century. There is a constant expectation that fission reactor technologies of today will 'soon' be superseded by more advanced designs, new concepts like Generation IV, fusion reactors, etc. Nuclear industry is highly regulated and politicized and strong anti-nuclear lobbies led to stagnation. The presentation underlines the key activity areas of the nuclear knowledge: - providing guidance for policy formulation and implementation of nuclear knowledge management; - strengthening the contribution of nuclear knowledge in solving development problems; - facilitating knowledge creation and utilization; - implementing effective knowledge management systems; - preserving and maintaining nuclear knowledge; - securing sustainable human resources for the nuclear sector; - enhancing nuclear education and training. Knowledge management in nuclear life cycle should cover all stages involved, namely: - design and engineering; - procurement; - manufacturing; - construction and commissioning; - operation and maintenance- refurbishment and decommissioning. In this context, Romania must change the Nuclear Educational System in order to face the requirements raised by Bologna Process and nuclear development. Possible solutions to attain this goal are illustrated in this presentation. (authors)

  15. Lead -- supply/demand outlook

    International Nuclear Information System (INIS)

    Schnull, T.

    1999-01-01

    As Japan goes--so goes the world. That was the title of a recent lead article in The Economist that soberly discussed the potential of much more severe global economic problems occurring, if rapid and coordinated efforts were not made to stabilize the economic situation in Asia in general, and in Japan in particular. During the first 6 months of last year, commodity markets reacted violently to the spreading economic problems in Asia. More recent currency and financial problems in Russia have exacerbated an already unpleasant situation. One commodity after another--including oil, many of the agricultural commodities, and each of the base metals--have dropped sharply in price. Many are now trading at multiyear lows. Until there is an overall improvement in the outlook for these regions, sentiment will likely continue to be negative, and metals prices will remain under pressure. That being said, lead has maintained its value better than many other commodities during these difficult times, finding support in relatively strong fundamentals. The author takes a closer look at those supply and demand fundamentals, beginning with consumption

  16. World uranium supply and demand

    International Nuclear Information System (INIS)

    Patterson, J.A.

    1980-01-01

    The role of nuclear energy is under increasing scrutiny and uncertainty. None the less, there will be an increasing need for expansion of uranium supply to fuel committed reactors. Longer-term demand projections are very uncertain. Improved knowledge of the extent of world resources and their availability and economics is needed to support planning for reactor development, especially for breeder reactors, and for fuel-cycle development, especially enrichment, and reprocessing and recycle of uranium and plutonium. Efforts to date to estimate world uranium resources have been very useful but have largely reflected the state of available knowledge for the lower cost resources in regions that have received considerable exploration efforts. The IUREP evaluation of world resources provides an initial speculative estimate of world resources, including areas not previously appraised. Projections of long-range supply from the estimated resources suggest that the high-growth nuclear cases using once-through cycle may not be supportable for very long. However, additional effort is needed to appraise and report more completely and consistently on world resources, the production levels attainable from these resources, and the economic and price characteristics of such production. (author)

  17. BATMAN: MOS Spectroscopy on Demand

    Science.gov (United States)

    Molinari, E.; Zamkotsian, F.; Moschetti, M.; Spano, P.; Boschin, W.; Cosentino, R.; Ghedina, A.; González, M.; Pérez, H.; Lanzoni, P.; Ramarijaona, H.; Riva, M.; Zerbi, F.; Nicastro, L.; Valenziano, L.; Di Marcantonio, P.; Coretti, I.; Cirami, R.

    2016-10-01

    Multi-Object Spectrographs (MOS) are the major instruments for studying primary galaxies and remote and faint objects. Current object selection systems are limited and/or difficult to implement in next generation MOS for space and ground-based telescopes. A promising solution is the use of MOEMS devices such as micromirror arrays, which allow the remote control of the multi-slit configuration in real time. TNG is hosting a novelty project for real-time, on-demand MOS masks based on MOEMS programmable slits. We are developing a 2048×1080 Digital-Micromirror-Device-based (DMD) MOS instrument to be mounted on the Galileo telescope, called BATMAN. It is a two-arm instrument designed for providing in parallel imaging and spectroscopic capabilities. With a field of view of 6.8×3.6 arcmin and a plate scale of 0.2 arcsec per micromirror, this astronomical setup can be used to investigate the formation and evolution of galaxies. The wavelength range is in the visible and the spectral resolution is R=560 for a 1 arcsec object, and the two arms will have 2k × 4k CCD detectors. ROBIN, a BATMAN demonstrator, has been designed, realized and integrated. We plan to have BATMAN first light by mid-2016.

  18. Chinese energy demand falls back

    Energy Technology Data Exchange (ETDEWEB)

    Smil, V.

    1977-10-01

    China's growth in energy demand and production declined in 1976, partly because of difficulty of sustaining a rapid 5.4 percent growth and partly because of the disruptions caused by a major earthquake and the deaths of Mao Tse-Tung and Chou En-Lai. The earthquake, which damaged all mines, the power station, refineries, and transportation lines in the Tangshan area, has had serious economic consequences. The failure to back up a growing coal industry with adequate investments and mechanization was recognized in 1975 and prompted a 10-year modernization program. Progress has been made with new mine shafts, pulverizing equipment, and the use of small mines for local industries. Oil and gas production increased after the discovery of new fields and the use of new technology in the hydrocarbon industries. Ports and terminal facilities to handle large tankers will increase China's oil export traffic. Electricity generation increased with new power facilities, although China's dependence on human and animal power is still a major factor. Changes in energy consumption patterns are developing, but industry still represents 50 percent and transportation less than 10 percent. (DCK)

  19. Oxygen diffusion in zircon

    Science.gov (United States)

    Watson, E. B.; Cherniak, D. J.

    1997-05-01

    Oxygen diffusion in natural, non-metamict zircon was characterized under both dry and water-present conditions at temperatures ranging from 765°C to 1500°C. Dry experiments were performed at atmospheric pressure by encapsulating polished zircon samples with a fine powder of 18O-enriched quartz and annealing the sealed capsules in air. Hydrothermal runs were conducted in cold-seal pressure vessels (7-70 MPa) or a piston cylinder apparatus (400-1000 MPa) on zircon samples encapsulated with both 18O-enriched quartz and 18O water. Diffusive-uptake profiles of 18O were measured in all samples with a particle accelerator, using the 18O(p, α) 15N reaction. For dry experimental conditions at 1100-1500°C, the resulting oxygen diffusivities (24 in all) are well described by: D dry (m 2/s) = 1.33 × 10 -4exp(-53920/T) There is no suggestion of diffusive anisotropy. Under wet conditions at 925°C, oxygen diffusion shows little or no dependence upon P H 2O in the range 7-1000 MPa, and is insensitive to total pressure as well. The results of 27 wet experiments at 767-1160°C and 7-1000 MPa can be described a single Arrhenius relationship: D wet (m 2/s) = 5.5 × 10 -12exp(-25280/T) The insensitivity of oxygen diffusion to P H 2O means that applications to geologic problems can be pursued knowing only whether the system of interest was 'wet' (i.e., P H 2O > 7MPa ) or 'dry'. Under dry conditions (presumably rare in the crust), zircons are extremely retentive of their oxygen isotopic signatures, to the extent that δ 18O would be perturbed at the center of a 200 μm zircon only during an extraordinarily hot and protracted event (e.g., 65 Ma at 900°C). Under wet conditions, δ 18O may or may not be retained in the central regions of individual crystals, cores or overgrowth rims, depending upon the specific thermal history of the system.

  20. Oxygen Transport Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay

    2008-08-30

    The focus of this research was to develop new membrane materials by synthesizing different compounds and determining their defect structures, crystallographic structures and electrical properties. In addition to measuring electrical conductivity, oxygen vacancy concentration was also evaluated using thermogravimetry, Neutron diffraction and Moessbauer Spectroscopy. The reducing conditions (CO{sub 2}/CO/H{sub 2} gas mixtures with steam) as encountered in a reactor environment can be expected to have significant influence on the mechanical properties of the oxides membranes. Various La based materials with and without Ti were selected as candidate membrane materials for OTM. The maximum electrical conductivity of LSF in air as a function of temperature was achieved at < 600 C and depends on the concentration of Sr (acceptor dopant). Oxygen occupancy in LSF was estimated using Neutron diffractometry and Moessbauer Spectroscopy by measuring magnetic moment changes depending on the Fe{sup 3+} and Fe{sup 4+} ratio. After extensive studies of candidate materials, lanthanum ferrites (LSF and LSFT) were selected as the favored materials for the oxygen transport membrane (OTM). LSF is a very good material for an OTM because of its high electronic and oxygen ionic conductivity if long term stability and mechanical strength are improved. LSFT not only exhibits p-type behavior in the high oxygen activity regime, but also has n-type conduction in reducing atmospheres. Higher concentrations of oxygen vacancies in the low oxygen activity regime may improve the performance of LSFT as an OTM. The hole concentration is related to the difference in the acceptor and donor concentration by the relation p = [Sr'{sub La}]-[Ti{sm_bullet}{sub Fe}]. The chemical formulation predicts that the hole concentration is, p = 0.8-0.45 or 0.35. Experimental measurements indicated that p is about {approx} 0.35. The activation energy of conduction is 0.2 eV which implies that LSCF conducts via the

  1. Function and Content of Maternal Demands: Developmental Significance of Early Demands for Competent Action.

    Science.gov (United States)

    Kuczynski, Leon; Kochanska, Grazyna

    1995-01-01

    Examined mothers' demands during mothers' interactions with their 1.5- to 3.5-year olds. Mothers with authoritative child-rearing attitudes emphasized proactive, competence-oriented demands and avoided regulatory control. Maternal demands for competent action predicted fewer behavior problems in their children at age five; maternal demands focused…

  2. The development of demand elasticity model for demand response in the retail market environment

    NARCIS (Netherlands)

    Babar, M.; Nguyen, P.H.; Kamphuis, I.G.

    2015-01-01

    In the context of liberalized energy market, increase in distributed generation, storage and demand response has expanded the price elasticity of demand, thus causing the addition of uncertainty to the supply-demand chain of power system. In order to cope with the challenges of demand uncertainty

  3. Theory of oxygen isotope exchange

    NARCIS (Netherlands)

    den Otter, M.W.; Boukamp, Bernard A.; Bouwmeester, Henricus J.M.

    2001-01-01

    Transients for oxygen molecular mass numbers 32, 34 and 36 are derived which can be used for the interpretation of oxygen isotope exchange data based on measurement of concentrations of 16O2, 16O18O and 18O2 in the gas phase. Key parameters in the theory are the rate at which oxygen molecules are

  4. Mixed oxygen ion/electron-conducting ceramics for oxygen separation

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, J.W.; Armstrong, T.R.; Armstrong, B.L. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-08-01

    Mixed oxygen ion and electron-conducting ceramics are unique materials that can passively separate high purity oxygen from air. Oxygen ions move through a fully dense ceramic in response to an oxygen concentration gradient, charge-compensated by an electron flux in the opposite direction. Compositions in the system La{sub 1{minus}x}M{sub x}Co{sub 1{minus}y{minus}z}Fe{sub y}N{sub z}O{sub 3{minus}{delta}}, perovskites where M=Sr, Ca, and Ba, and N=Mn, Ni, Cu, Ti, and Al, have been prepared and their electrical, oxygen permeation, oxygen vacancy equilibria, and catalytic properties evaluated. Tubular forms, disks, and asymmetric membrane structures, a thin dense layer on a porous support of the same composition, have been fabricated for testing purposes. In an oxygen partial gradient, the passive oxygen flux through fully dense structures was highly dependent on composition. An increase in oxygen permeation with increased temperature is attributed to both enhanced oxygen vacancy mobility and higher vacancy populations. Highly acceptor-doped compositions resulted in oxygen ion mobilities more than an order of magnitude higher than yttria-stabilized zirconia. The mixed conducting ceramics have been utilized in a membrane reactor configuration to upgrade methane to ethane and ethylene. Conditions were established to balance selectivity and throughput in a catalytic membrane reactor constructed from mixed conducting ceramics.

  5. Evolving Oxygen Landscape of the Early Atmosphere and Oceans

    Science.gov (United States)

    Lyons, T. W.; Reinhard, C. T.; Planavsky, N. J.

    2013-12-01

    we see evidence for an oxygenation event that significantly predated recent evidence for ocean ventilation in the post-glacial Ediacaran ocean. The trigger that facilitated the transition out of the oxygen-lean ';boring billion' is an area of active study. Additional evidence points to the likelihood of rising and falling oxygen levels through the later Neoproterozoic, which would have had a strong impact on early animal diversification and development of oxygen-demanding ecologies marked by large animals with complex trophic relationships. These observations now provide a context for interpreting the cause-and-effect relationships among the late Proterozoic rise in oxygen, the onset and dynamics of global-scale Neoproterozoic glaciation, metazoan diversification, and large-scale tectonic processes as surface expressions of deep-Earth processes.

  6. Resource Demand Scenarios for the Major Metals.

    Science.gov (United States)

    Elshkaki, Ayman; Graedel, T E; Ciacci, Luca; Reck, Barbara K

    2018-03-06

    The growth in metal use in the past few decades raises concern that supplies may be insufficient to meet demands in the future. From the perspective of historical and current use data for seven major metals-iron, manganese, aluminum, copper, nickel, zinc, and lead-we have generated several scenarios of potential metal demand from 2010 to 2050 under alternative patterns of global development. We have also compared those demands with various assessments of potential supply to midcentury. Five conclusions emerge: (1) The calculated demand for each of the seven metals doubles or triples relative to 2010 levels by midcentury; (2) The largest demand increases relate to a scenario in which increasingly equitable values and institutions prevail throughout the world; (3) The metal recycling flows in the scenarios meet only a modest fraction of future metals demand for the next few decades; (4) In the case of copper, zinc, and perhaps lead, supply may be unlikely to meet demand by about midcentury under the current use patterns of the respective metals; (5) Increased rates of demand for metals imply substantial new energy provisioning, leading to increases in overall global energy demand of 21-37%. These results imply that extensive technological transformations and governmental initiatives could be needed over the next several decades in order that regional and global development and associated metal demand are not to be constrained by limited metal supply.

  7. Use of an oxygen concentrator in a Nigerian neonatal unit: economic implications and reliability.

    Science.gov (United States)

    Mokuolu, Olugbenga A; Ajayi, Oluade A

    2002-09-01

    A 3-year experience of using an oxygen concentrator in a Nigerian newborn unit and economic appraisal of its effectiveness is reported. The oxygen concentrator is a device that absorbs nitrogen from ambient air, with a resultant oxygen concentration of 85 to 95% at different flow rates. The oxygen concentrator met our oxygen needs which averaged 18 hours a day, and had a huge cost advantage over the oxygen cylinders. The cost of oxygen via cylinder for just one patient for a year exceeds the initial capital outlay for a concentrator. The Puritan-Bennett oxygen concentrator has a lifespan of at least 7 years and is virtually maintenance-free for the 1st 26,400 hours of use, after which some major components might need replacement. We conclude that in developing countries oxygen concentrators are a more cost-effective, reliable and convenient means of oxygen supply than oxygen cylinders, and recommend their use where there is a high demand for oxygen.

  8. A role for haemolymph oxygen capacity in heat tolerance of eurythermal crabs.

    Directory of Open Access Journals (Sweden)

    Folco eGiomi

    2013-05-01

    Full Text Available Heat tolerance in aquatic ectotherms is constrained by a mismatch, occurring at high temperatures, between oxygen delivery and demand which compromises the maintenance of aerobic scope. The present study analyses how the wide thermal tolerance range of an eurythermal model species, the green crab Carcinus maenas is supported and limited by its ability to sustain efficient oxygen transport to tissues. Similar to other eurytherms, C. maenas sustains naturally occurring acute warming events through the integrated response of circulatory and respiratory systems. The response of C. maenas to warming is characterized by two phases. During initial warming, oxygen consumption and heart rate increase while stroke volume and haemolymph oxygen partial pressures decrease. During further warming, dissolved oxygen levels in the venous compartment decrease below the threshold of full haemocyanin oxygen saturation. The progressive release of haemocyanin bound oxygen with further warming follows an exponential pattern, thereby saving energy in oxygen transport and causing an associated leveling off of metabolic rate. According to the concept of oxygen and capacity limited thermal tolerance, this indicates that the thermal tolerance window is widened by the increasing contribution of haemocyanin oxygen transport and associated energy savings in cardiocirculation. Haemocyanin bound oxygen sustains cardiac performance to cover the temperature range experienced by C. maenas in the field. To our knowledge this is the first study providing evidence of a relationship between thermal tolerance and blood (haemolymph oxygen transport in eurythermal invertebrates.

  9. A role for haemolymph oxygen capacity in heat tolerance of eurythermal crabs.

    Science.gov (United States)

    Giomi, Folco; Pörtner, Hans-Otto

    2013-01-01

    Heat tolerance in aquatic ectotherms is constrained by a mismatch, occurring at high temperatures, between oxygen delivery and demand which compromises the maintenance of aerobic scope. The present study analyses how the wide thermal tolerance range of an eurythermal model species, the green crab Carcinus maenas is supported and limited by its ability to sustain efficient oxygen transport to tissues. Similar to other eurytherms, C. maenas sustains naturally occurring acute warming events through the integrated response of circulatory and respiratory systems. The response of C. maenas to warming can be characterized by two phases. During initial warming, oxygen consumption and heart rate increase, while stroke volume and haemolymph oxygen partial pressure decrease. During further warming, dissolved oxygen levels in the venous compartment decrease below the threshold of full haemocyanin oxygen saturation. The progressive release of haemocyanin bound oxygen with further warming follows an exponential pattern, thereby saving energy in oxygen transport and causing an associated leveling off of metabolic rate. According to the concept of oxygen and capacity limited thermal tolerance (OCLTT), this indicates that the thermal tolerance window is widened by the increasing contribution of haemocyanin oxygen transport and associated energy savings in cardiocirculation. Haemocyanin bound oxygen sustains cardiac performance to cover the temperature range experienced by C. maenas in the field. To our knowledge this is the first study providing evidence of a relationship between thermal tolerance and blood (haemolymph) oxygen transport in a eurythermal invertebrate.

  10. The World Demand for Catfish Pangasius

    DEFF Research Database (Denmark)

    Nguyen, Thong Tien; Roth, Eva; Nielsen, Max

    2014-01-01

    flexibilities are less than 1. While there are many demand studies for other whitefish species and salmon, which are strongly competed by catfish in many markets, there is a lack of demand study for Pangasius catfish. Therefore, this study will supplement seafood demand literature and be meaningful for seafood......In this paper we present a world demand system for Pangasius catfish products. We use solely exporting data from Vietnam for estimating a non-linear Almost Ideal Demand System because Vietnam accounts for more than 90% catfish export value of the world and the products exported are mostly...... in filleted form. The demand system includes seven equations representing for most important markets that are ASEAN & EAST ASIA, NORTH AMERICA, OCEANIA, RUSIAN & EASTERN EU, SOUTH & CENTRAL AMERICA, WESTERN EU, and ROW (rest of the world) markets. The monthly data are updating from January 2007 to March 2014...

  11. Demand forecast model based on CRM

    Science.gov (United States)

    Cai, Yuancui; Chen, Lichao

    2006-11-01

    With interiorizing day by day management thought that regarding customer as the centre, forecasting customer demand becomes more and more important. In the demand forecast of customer relationship management, the traditional forecast methods have very great limitation because much uncertainty of the demand, these all require new modeling to meet the demands of development. In this paper, the notion is that forecasting the demand according to characteristics of the potential customer, then modeling by it. The model first depicts customer adopting uniform multiple indexes. Secondly, the model acquires characteristic customers on the basis of data warehouse and the technology of data mining. The last, there get the most similar characteristic customer by their comparing and forecast the demands of new customer by the most similar characteristic customer.

  12. Physiological demands of off-road vehicle riding.

    Science.gov (United States)

    Burr, Jamie F; Jamnik, Veronica K; Shaw, Jim A; Gledhill, Norman

    2010-07-01

    The purpose of this study was to characterize the physiological demands of recreational off-road vehicle riding under typical riding conditions using habitual recreational off-road vehicle riders (n = 128). Comparisons of the physical demands of off-road vehicle riding were made between vehicle types (all-terrain vehicle (ATV) and off-road motorcycle (ORM)) to the demands of common recreational activities. Habitual riders (ATV = 56, ORM = 72) performed strength assessments before and after a representative trail ride (48 +/- 24.2 min), and ambulatory oxygen consumption was measured during one lap (24.2 +/- 11.8 min) of the ride. The mean VO2 requirement (mL x kg(-1) x min(-1)) while riding an off-road vehicle was 12.1 +/- 4.9 for ATV and 21.3 +/- 7.1 for ORM (P = 0.002), which is comparable to the VO2 required of many common recreational activities. Temporal analysis of activity intensity revealed approximately 14% of an ATV ride and 38% of an ORM ride are within the intensity range (940% VO2 reserve) required to achieve changes in aerobic fitness. Riding on a representative course also led to muscular fatigue, particularly in the upper body. On the basis of the measured metabolic demands, evidence of muscular strength requirements, and the associated caloric expenditures with off-road vehicle riding, this alternative form of activity conforms to the recommended physical activity guidelines and can be effective for achieving beneficial changes in health and fitness.

  13. Owning, letting and demanding second homes

    DEFF Research Database (Denmark)

    Bloze, Gintautas; Skak, Morten

    register data and presents estimations of the probability of owning a second home, the decision to let the second home and the number of let weeks per year. Also income elasticities for primary and second housing demand are estimated. We find a conventional monotonic increase in demand elasticities...... for primary housing demand for non-owners of second homes; however, owners of second homes have the highest income elasticity in the middle income group....

  14. Pathological demand avoidance: Exploring the behavioural profile.

    OpenAIRE

    O Nions, E.; Viding, E.; Greven, C. U.; Ronald, A.; Happé, F.

    2014-01-01

    'Pathological Demand Avoidance' is a term increasingly used by practitioners in the United Kingdom. It was coined to describe a profile of obsessive resistance to everyday demands and requests, with a tendency to resort to 'socially manipulative' behaviour, including outrageous or embarrassing acts. Pathological demand avoidance is thought to share aspects of social impairment with autism spectrum disorders, but autism spectrum disorder-appropriate strategies, such as routine and repetition, ...

  15. Modelling the Demand for Money in Pakistan

    OpenAIRE

    Qayyum, Abdul

    2005-01-01

    The study estimates the dynamic demand for money (M2) function in Pakistan by employing cointegration analysis and error correction mechanism. The parameters of preferred model are found to be super-exogenous for the relevant class of interventions. It is found that the rate of inflation is an important determinant of money demand in Pakistan. The analysis reveals that the rates of interest, market rate, and bond yield are important for the long-run money demand behaviour. Since the preferred...

  16. Stream Macroinvertebrate Occurrence along Gradients in Organic Pollution and Eutrophication

    DEFF Research Database (Denmark)

    Friberg, Nikolai; Skriver, Jens; Larsen, Søren Erik

    2010-01-01

    We analysed a large number of concurrent samples of macroinvertebrate communities and chemical indicators of eutrophication and organic pollution [total-P, total-N, NH4-N, biological oxygen demand (BOD5)] from 594 Danish stream sites. Samples were taken over an 11-year time span as part of the Da......We analysed a large number of concurrent samples of macroinvertebrate communities and chemical indicators of eutrophication and organic pollution [total-P, total-N, NH4-N, biological oxygen demand (BOD5)] from 594 Danish stream sites. Samples were taken over an 11-year time span as part...

  17. Modeling of Aircraft Deicing Fluid Induced Biochemical Oxygen Demand in Subsurface-Flow Constructed Treatment Wetlands

    Science.gov (United States)

    2009-03-01

    Jukka A. Rintala, Christof Holliger, and Alla N. Nozhevnikova. “Evaluation of Kinetic Coefficients Using Intergrated Monod and Haldane Models for...Rousseau, Diederik P. L., Peter A Vanrolleghem, and Niels De Pauw. “Model-Based Design of Horizontal Subsurface Flow constructed Treatment

  18. Demand controlled ventilation in a bathroom

    DEFF Research Database (Denmark)

    Mortensen, Dorthe Kragsig; Nielsen, Toke Rammer; Topp, Claus

    2008-01-01

    consumption during periods where the demand for ventilation is low and poor indoor climate during periods where the demand for ventilation is high. Controlling the ventilation rate by demand can improve the energy performance of the ventilation system and the indoor climate. This paper compares the indoor...... climate and energy consumption of a Constant Air Volume (CAV) system and a Demand Controlled Ventilation (DCV) system for two different bathroom designs. The air change rate of the CAV system corresponded to 0.5h-1. The ventilation rate of the DCV system was controlled by occupancy and by the relative...

  19. Money Demand Features in CEE Countries

    Directory of Open Access Journals (Sweden)

    Valentina-Ioana MERA

    2016-01-01

    Full Text Available The existence of a stable relationship between money demand and its determinants is important for the efficiency of monetary policy. In this paper we carried a preliminary analysis on the variables that can influence money demand in five Central and Eastern European countries (Bulgaria, Czech Republic, Hungary, Poland and Romania in order to determine which characteristics define the evolution of money demand and its determinants, and how volatile they are. The results indicate a number of similarities in terms of monetary development and also suggest that some additional variables that may influence money demand in this specific sample.

  20. Dissolved oxygen - A target indicator in determining use of the Gulf of Kachchh waters

    Digital Repository Service at National Institute of Oceanography (India)

    Desa, E.; Zingde, M.D.; Vethamony, P.; Babu, M.T.; DeSousa, S.N.; Verlecar, X.N.

    for the SW-1 waters. BOD -DO simulation shows that when effluents containing a BOD concentration of 50.0 mgl sup(-1) are introduced at three select locations, DO reduces from 5.1 mgl sup(-1) to 3.1,5.0 and 3.8 mgl sup(-1), respectively, indicating a strong...

  1. Oxygen-Methane Thruster

    Science.gov (United States)

    Pickens, Tim

    2012-01-01

    An oxygen-methane thruster was conceived with integrated igniter/injector capable of nominal operation on either gaseous or liquid propellants. The thruster was designed to develop 100 lbf (approximately 445 N) thrust at vacuum conditions and use oxygen and methane as propellants. This continued development included refining the design of the thruster to minimize part count and manufacturing difficulties/cost, refining the modeling tools and capabilities that support system design and analysis, demonstrating the performance of the igniter and full thruster assembly with both gaseous and liquid propellants, and acquiring data from this testing in order to verify the design and operational parameters of the thruster. Thruster testing was conducted with gaseous propellants used for the igniter and thruster. The thruster was demonstrated to work with all types of propellant conditions, and provided the desired performance. Both the thruster and igniter were tested, as well as gaseous propellants, and found to provide the desired performance using the various propellant conditions. The engine also served as an injector testbed for MSFC-designed refractory combustion chambers made of rhenium.

  2. OXYGEN TRANSPORT CERAMIC MEMBRANES

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2000-10-01

    This is the third quarterly report on oxygen Transport Ceramic Membranes. In the following, the report describes the progress made by our university partners in Tasks 1 through 6, experimental apparatus that was designed and built for various tasks of this project, thermodynamic calculations, where applicable and work planned for the future. (Task 1) Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. (Task 2) Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. (Task 3) Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. (Task 4) Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. (Task 5) Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. (Task 6) Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

  3. OXYGEN ABUNDANCES IN CEPHEIDS

    International Nuclear Information System (INIS)

    Luck, R. E.; Andrievsky, S. M.; Korotin, S. N.; Kovtyukh, V. V.

    2013-01-01

    Oxygen abundances in later-type stars, and intermediate-mass stars in particular, are usually determined from the [O I] line at 630.0 nm, and to a lesser extent, from the O I triplet at 615.7 nm. The near-IR triplets at 777.4 nm and 844.6 nm are strong in these stars and generally do not suffer from severe blending with other species. However, these latter two triplets suffer from strong non-local thermodynamic equilibrium (NLTE) effects and thus see limited use in abundance analyses. In this paper, we derive oxygen abundances in a large sample of Cepheids using the near-IR triplets from an NLTE analysis, and compare those abundances to values derived from a local thermodynamic equilibrium (LTE) analysis of the [O I] 630.0 nm line and the O I 615.7 nm triplet as well as LTE abundances for the 777.4 nm triplet. All of these lines suffer from line strength problems making them sensitive to either measurement complications (weak lines) or to line saturation difficulties (strong lines). Upon this realization, the LTE results for the [O I] lines and the O I 615.7 nm triplet are in adequate agreement with the abundance from the NLTE analysis of the near-IR triplets.

  4. Sterilization by oxygen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Adir Jose; Mansano, Ronaldo Domingues; Andreoli Pinto, Terezinha de Jesus; Ruas, Ronaldo; Silva Zambon, Luis da; Silva, Monica Valero da; Verdonck, Patrick Bernard

    2004-07-31

    The use of polymeric medical devices has stimulated the development of new sterilization methods. The traditional techniques rely on ethylene oxide, but there are many questions concerning the carcinogenic properties of the ethylene oxide residues adsorbed on the materials after processing. Another common technique is the gamma irradiation process, but it is costly, its safe operation requires an isolated site and it also affects the bulk properties of the polymers. The use of a gas plasma is an elegant alternative sterilization technique. The plasma promotes an efficient inactivation of the micro-organisms, minimises the damage to the materials and presents very little danger for personnel and the environment. Pure oxygen reactive ion etching type of plasmas were applied to inactivate a biologic indicator, the Bacillus stearothermophilus, to confirm the efficiency of this process. The sterilization processes took a short time, in a few minutes the mortality was complete. In situ analysis of the micro-organisms' inactivating time was possible using emission spectrophotometry. The increase in the intensity of the 777.5 nm oxygen line shows the end of the oxidation of the biologic materials. The results were also observed and corroborated by scanning electron microscopy.

  5. High Selectivity Oxygen Delignification

    Energy Technology Data Exchange (ETDEWEB)

    Arthur J. Ragauskas

    2005-09-30

    The overall objective of this program was to develop improved extended oxygen delignification (EOD) technologies for current U.S. pulp mill operations. This was accomplished by: (1) Identifying pulping conditions that optimize O and OO performance; (2) Identifying structural features of lignin that enhance reactivity towards EOD of high kappa pulps; (3) Identifying factors minimizing carbohydrate degradation and improve pulp strength of EOD high kappa pulps; (4) Developing a simple, reproducible method of quantifying yield gains from EOD; and (5) Developing process conditions that significantly reduce the capital requirements of EOD while optimizing the yield benefits. Key research outcomes included, demonstrating the use of a mini-O sequence such as (E+O)Dkf:0.05(E+O) or Dkf:0.05(E+O)(E+O) without interstage washing could capture approximately 60% of the delignification efficiency of a conventional O-stage without the major capital requirements associated with an O-stage for conventional SW kraft pulps. The rate of formation and loss of fiber charge during an O-stage stage can be employed to maximize net fiber charge. Optimal fiber charge development and delignification are two independent parameters and do not parallel each other. It is possible to utilize an O-stage to enhance overall cellulosic fiber charge of low and high kappa SW kraft pulps which is beneficial for physical strength properties. The application of NIR and multi-variant analysis was developed into a rapid and simple method of determining the yield of pulp from an oxygen delignification stage that has real-world mill applications. A focus point of this program was the demonstration that Kraft pulping conditions and oxygen delignification of high and low-kappa SW and HW pulps are intimately related. Improved physical pulp properties and yield can be delivered by controlling the H-factor and active alkali charge. Low AA softwood kraft pulp with a kappa number 30 has an average improvement of 2% in

  6. Drivers of U.S. mineral demand

    Science.gov (United States)

    Sznopek, John L.

    2006-01-01

    Introduction: The word 'demand' has different meanings for different people. To some, it means their 'wants and needs,' to others it is what they consume. Yet, when considering economics, demand refers to the specific amounts of goods or services that individuals will purchase at various prices. Demand is measured over a given time period. It is determined by a number of factors including income, tastes, and the price of complementary and substitute goods. In this paper, the term consumption is used fairly synonymously with the term demand. Most mineral commodities, like iron ore, copper, zinc, and gravel, are intermediate goods, which means that they are used in the production of other goods, called final goods. Demand for intermediate goods is called derived demand because such demand is derived from the demand for final goods. When demand increases for a commodity, generally the price rises. With everything else held constant, this increases the profits for those who provide this commodity. Normally, this would increase profits of existing producers and attract new producers to the market. When demand for a commodity decreases, generally the price falls. Normally, this would cause profits to fall and, as a consequence, the least efficient firms may be forced from the industry. Demand changes for specific materials as final goods or production techniques are reengineered while maintaining or improving product performance, for example, the use of aluminum in the place of copper in long distance electrical transmission lines or plastic replacing steel in automobile bumpers. Substitution contributes to efficient material usage by utilizing cheaper or technically superior materials. In this way, it may also alleviate materials scarcity. If a material becomes relatively scarce (and thus more expensive), a more abundant (and less expensive) material generally replaces it (Wagner and others, 2003, p. 91).

  7. Ethanol demand in Brazil: Regional approach

    International Nuclear Information System (INIS)

    Freitas, Luciano Charlita de; Kaneko, Shinji

    2011-01-01

    Successive studies attempting to clarify national aspects of ethanol demand have assisted policy makers and producers in defining strategies, but little information is available on the dynamic of regional ethanol markets. This study aims to analyze the characteristics of ethanol demand at the regional level taking into account the peculiarities of the developed center-south and the developing north-northeast regions. Regional ethanol demand is evaluated based on a set of market variables that include ethanol price, consumer's income, vehicle stock and prices of substitute fuels; i.e., gasoline and natural gas. A panel cointegration analysis with monthly observations from January 2003 to April 2010 is employed to estimate the long-run demand elasticity. The results reveal that the demand for ethanol in Brazil differs between regions. While in the center-south region the price elasticity for both ethanol and alternative fuels is high, consumption in the north-northeast is more sensitive to changes in the stock of the ethanol-powered fleet and income. These, among other evidences, suggest that the pattern of ethanol demand in the center-south region most closely resembles that in developed nations, while the pattern of demand in the north-northeast most closely resembles that in developing nations. - Research highlights: → Article consists of a first insight on regional demand for ethanol in Brazil. → It proposes a model with multiple fuels, i.e., hydrous ethanol, gasohol and natural gas. → Results evidence that figures for regional demand for ethanol differ amongst regions and with values reported for national demand. → Elasticities for the center-south keep similarities to patterns for fuel demand in developed nations while coefficients for the north-northeast are aligned to patterns on developing countries.

  8. Ethanol demand in Brazil: Regional approach

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Luciano Charlita de, E-mail: lucianofreitas@hiroshima-u.ac.j [Graduate School for International Development and Cooperation, Development Policy, Hiroshima University 1-5-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8529 (Japan); Kaneko, Shinji [Graduate School for International Development and Cooperation, Development Policy, Hiroshima University 1-5-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8529 (Japan)

    2011-05-15

    Successive studies attempting to clarify national aspects of ethanol demand have assisted policy makers and producers in defining strategies, but little information is available on the dynamic of regional ethanol markets. This study aims to analyze the characteristics of ethanol demand at the regional level taking into account the peculiarities of the developed center-south and the developing north-northeast regions. Regional ethanol demand is evaluated based on a set of market variables that include ethanol price, consumer's income, vehicle stock and prices of substitute fuels; i.e., gasoline and natural gas. A panel cointegration analysis with monthly observations from January 2003 to April 2010 is employed to estimate the long-run demand elasticity. The results reveal that the demand for ethanol in Brazil differs between regions. While in the center-south region the price elasticity for both ethanol and alternative fuels is high, consumption in the north-northeast is more sensitive to changes in the stock of the ethanol-powered fleet and income. These, among other evidences, suggest that the pattern of ethanol demand in the center-south region most closely resembles that in developed nations, while the pattern of demand in the north-northeast most closely resembles that in developing nations. - Research highlights: {yields} Article consists of a first insight on regional demand for ethanol in Brazil. {yields} It proposes a model with multiple fuels, i.e., hydrous ethanol, gasohol and natural gas. {yields} Results evidence that figures for regional demand for ethanol differ amongst regions and with values reported for national demand. {yields} Elasticities for the center-south keep similarities to patterns for fuel demand in developed nations while coefficients for the north-northeast are aligned to patterns on developing countries.

  9. Medical oxygen and air travel.

    Science.gov (United States)

    Lyznicki, J M; Williams, M A; Deitchman, S D; Howe, J P

    2000-08-01

    This report responds to a resolution that asked the American Medical Association (AMA) to take action to improve airport and airline accommodations for passengers requiring medical oxygen. Information for the report was derived from a search of the MEDLINE database and references listed in pertinent articles, as well as through communications with experts in aerospace and emergency medicine. Based on this information, the AMA Council on Scientific Affairs determined that commercial air travel exposes passengers to altitude-related hypoxia and gas expansion, which may cause some passengers to experience significant symptoms and medical complications during flight. Medical guidelines are available to help physicians evaluate and counsel potential passengers who are at increased risk of inflight hypoxemia. Supplemental oxygen may be needed for some passengers to maintain adequate tissue oxygenation and prevent hypoxemic complications. For safety and security reasons, federal regulations prohibit travelers from using their own portable oxygen system onboard commercial aircraft. Many U.S. airlines supply medical oxygen for use during flight but policies and procedures vary. Oxygen-dependent passengers must make additional arrangements for the use of supplemental oxygen in airports. Uniform standards are needed to specify procedures and equipment for the use of medical oxygen in airports and aboard commercial aircraft. Revision of federal regulations should be considered to accommodate oxygen-dependent passengers and permit them to have an uninterrupted source of oxygen from departure to destination.

  10. Oxygen effect and intracellular oxygen content (adaptation hypothesis)

    Energy Technology Data Exchange (ETDEWEB)

    Yarmonenko, S P; Ehpshtejn, I M [Akademiya Meditsinskikh Nauk SSSR, Moscow. Onkologicheskij Tsentr

    1977-01-01

    Experimental data indicating that a radiomodifying action of hypoxia is dependent on the ''prehistory'' of the irradiated object are considered. This dependence manifests itself in a decreased protective action of acute hypoxia on the hypoxia-adapted objects. To explain this a hypothesis is proposed connecting a degree of cell radiosensitivity modification, determined by the oxygen effect, with the intracellular oxygen content. The latter, in accord with current ideas, is regulated by variations in the diffusion resistance to oxygen shown by the cytoplasmic membranes depending on the energy level of the cell and the degree of its oxygenation.

  11. Oxygen effect and intracellular oxygen content (adaptation hypothesis)

    International Nuclear Information System (INIS)

    Yarmonenko, S.P.; Ehpshtejn, I.M.

    1977-01-01

    Experimental data indicating that a radiomodifying action of hypoxia is dependent on the ''prehistory'' of the irradiated object are considered. This dependence manifests itself in a decreased protective action of acute hypoxia on the hypoxia-adapted objects. To explain this a hypothesis is proposed connecting a degree of cell radiosensitivity modification, determined by the oxygen effect, with the intracellular oxygen content. The latter, in accord with current ideas, is regulated by variations in the diffusion resistance to oxygen shown by the cytoplasmic membranes depending on the energy level of the cell and the degree of its oxygenation

  12. P. Electricity demand, substitution and resources

    International Nuclear Information System (INIS)

    1976-01-01

    This report discusses the demand for electricity in New Zealand, the accuracy of demand predictions, and whether some other form of energy could be substituted for electricity. It then discusses past and possible future electricity generation in New Zealand by geothermal steam and hydro power and the resources of gas and coal that could be made available for electricity generation

  13. Water Demand Management Policy Brief No

    International Development Research Centre (IDRC) Digital Library (Canada)

    Bob Stanley

    Water demand management ― WDM ― can be hard to define. More an issue of policy than of technology, it is about managing and moderating our demands for good quality fresh water. It is less a matter of piping and pumps and more a tool ...

  14. Using imperfect advance demand information in forecasting

    NARCIS (Netherlands)

    Tan, T.

    2008-01-01

    In this paper, we consider the demand-forecasting problem of a make-to-stock system operating in a business-to-business environment where some customers provide information on their future orders, which are subject to changes in time, hence constituting imperfect advance demand information (ADI).

  15. Performance demand and sexual arousal in women

    NARCIS (Netherlands)

    Laan, E.; Everaerd, W.; van Aanhold, M. T.; Rebel, M.

    1993-01-01

    Up to now, no experimental studies have inquired into the possible role of performance demand in female sexuality. The objective of this study is to investigate the effects of performance demand on sexual arousal in functional women, using explicit instructions. Forty-eight female subjects were

  16. Teaching Aggregate Demand and Supply Models

    Science.gov (United States)

    Wells, Graeme

    2010-01-01

    The author analyzes the inflation-targeting model that underlies recent textbook expositions of the aggregate demand-aggregate supply approach used in introductory courses in macroeconomics. He shows how numerical simulations of a model with inflation inertia can be used as a tool to help students understand adjustments in response to demand and…

  17. Centrifuges help match supply and demand

    International Nuclear Information System (INIS)

    Crossley, P.S.

    1980-01-01

    Since the early 1970's the enrichment market situation has changed dramatically. Falling demands and increasing production capacity has resulted in over-capacity and stockpiles of enriched uranium. New trends in the industry are considered by analysing the following issues: supply and demand; technical development; build-up plans; contracting policies; enrichment economics; and nuclear safeguards. (U.K.)

  18. Lighting Systems Control for Demand Response

    NARCIS (Netherlands)

    Husen, S.A.; Pandharipande, A.; Tolhuizen, L.M.G.; Wang, Y.; Zhao, M.

    2012-01-01

    Lighting is a major part of energy consumption in buildings. Lighting systems will thus be one of the important component systems of a smart grid for dynamic load management services like demand response.In the scenario considered in this paper, under a demand response request, lighting systems in a

  19. Information management - Assessing the demand for information

    Science.gov (United States)

    Rogers, William H.

    1991-01-01

    Information demand is defined in terms of both information content (what information) and form (when, how, and where it is needed). Providing the information richness required for flight crews to be informed without overwhelming their information processing capabilities will require a great deal of automated intelligence. It is seen that the essence of this intelligence is comprehending and capturing the demand for information.

  20. Simple utility functions with Giffen demand

    DEFF Research Database (Denmark)

    Sørensen, Peter Norman

    2007-01-01

    Simple utility functions with the Giffen property are presented: locally, the demand curve for a good is upward sloping. The utility functions represent continuous, monotone, convex preferences......Simple utility functions with the Giffen property are presented: locally, the demand curve for a good is upward sloping. The utility functions represent continuous, monotone, convex preferences...

  1. Sectoral energy demand data: Sources and Issues

    International Nuclear Information System (INIS)

    Ounali, A.

    1991-01-01

    This chapter of the publication is dealing with Sectoral Energy Demand Data giving details about the Sources and Issues. Some comments are presented on rural energy surveys. Guidelines for the Definition and Desegregation of Sectoral Energy Consumption is given and Data Necessary for Sectoral Energy Demand Analysis is discussed

  2. Pathological Demand Avoidance: Exploring the Behavioural Profile

    Science.gov (United States)

    O'Nions, Elizabeth; Viding, Essi; Greven, Corina U; Ronald, Angelica; Happé, Francesca

    2014-01-01

    "Pathological Demand Avoidance" is a term increasingly used by practitioners in the United Kingdom. It was coined to describe a profile of obsessive resistance to everyday demands and requests, with a tendency to resort to "socially manipulative" behaviour, including outrageous or embarrassing acts. Pathological demand…

  3. Intermittent demand : Linking forecasting to inventory obsolescence

    NARCIS (Netherlands)

    Teunter, Ruud H.; Syntetos, Aris A.; Babai, M. Zied

    2011-01-01

    The standard method to forecast intermittent demand is that by Croston. This method is available in ERP-type solutions such as SAP and specialised forecasting software packages (e.g. Forecast Pro), and often applied in practice. It uses exponential smoothing to separately update the estimated demand

  4. 7 CFR 984.22 - Trade demand.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Trade demand. 984.22 Section 984.22 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 984.22 Trade demand. (a) Inshell. The quantity of merchantable inshell...

  5. Improving Water Demand Management Addressing Socioeconomic ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Efforts to conserve water by improving water demand management policies in the Middle East and North Africa are often slowed or even thwarted by a lack of political consensus and support for water demand management from key powerful stakeholders with vested interest in the status quo. This policy brief based on ...

  6. Improving Water Demand Management Addressing Socioeconomic ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2012-01-20

    Jan 20, 2012 ... Efforts to conserve water by improving water demand management policies in the Middle East and North Africa are often slowed or even thwarted by a lack of political consensus and support for water demand management from key powerful stakeholders with vested interest in the status quo. This policy ...

  7. Cost and Demand Characteristics of Telecom Networks

    DEFF Research Database (Denmark)

    Falch, Morten

    1997-01-01

    The Chapter presents the general characteristics of the cost and demand profiles for telecommunication services and identifies the barriers towards a free competitive market for telecommunication services related to these characteristics.......The Chapter presents the general characteristics of the cost and demand profiles for telecommunication services and identifies the barriers towards a free competitive market for telecommunication services related to these characteristics....

  8. Reporting, Recording, and Transferring Contingency Demand Data

    National Research Council Canada - National Science Library

    Smith, Bernard

    2000-01-01

    .... In this report, we develop a standard set of procedures for reporting and recording demand data at the contingency location and transferring contingency demand data to the home base - ensuring proper level allocation and valid worldwide peacetime operating stock (POS) and readiness spares package (RSP) requirements.

  9. Job demands, health perception and sickness absence

    NARCIS (Netherlands)

    Roelen, C.A.; Koopmans, P.C.; de Graaf, J.H.; van Zandbergen, J.W.; Groothoff, J.W.

    2007-01-01

    Background Investigation of the relations between job demands, health and sickness absence is required to design a strategy for the prevention of absence and disability. Aim To study the relationships between (physical and psychological) job demands, health perception and sickness absence. Methods

  10. WATER DEMAND PREDICTION USING ARTIFICIAL NEURAL ...

    African Journals Online (AJOL)

    This paper presents Hourly water demand prediction at the demand nodes of a water distribution network using NeuNet Pro 2.3 neural network software and the monitoring and control of water distribution using supervisory control. The case study is the Laminga Water Treatment Plant and its water distribution network, Jos.

  11. Oxygen rocking aqueous batteries utilizing reversible topotactic oxygen insertion/extraction in iron-based perovskite oxides Ca1-xLaxFeO3-δ

    Science.gov (United States)

    Hibino, Mitsuhiro; Kimura, Takeshi; Suga, Yosuke; Kudo, Tetsuichi; Mizuno, Noritaka

    2012-08-01

    Developments of large-scale energy storages with not only low cost and high safety but also abundant metals are significantly demanded. While lithium ion batteries are the most successful method, they cannot satisfy all conditions. Here we show the principle of novel lithium-free secondary oxygen rocking aqueous batteries, in which oxygen shuttles between the cathode and anode composed of iron-based perovskite-related oxides Ca0.5La0.5FeOz (2.5 topotactic oxygen extraction and reinsertion during discharge and charge processes.

  12. Cointegration and the demand for gasoline

    International Nuclear Information System (INIS)

    Bhaskara Rao, B.; Rao, Gyaneshwar

    2009-01-01

    Since the early 1970s, there has been a worldwide upsurge in the price of energy and in particular of gasoline. Therefore, demand functions for energy and its components like gasoline have received much attention. However, since confidence in the estimated demand functions is important for use in policy and forecasting, following [Amarawickrama, H.A., Hunt, L.C., 2008. Electricity demand for Sri Lanka: A time series analysis. Energy Economics 33, 724-739], this paper estimates the demand for gasoline is estimated with five alternative time series techniques with data from Fiji. Estimates with these alternative techniques are very close, and thus increase our confidence in them. We found that gasoline demand is both price and income inelastic.

  13. The balance of supply and demand

    International Nuclear Information System (INIS)

    Darmayan, P.

    1981-01-01

    The Supply and Demand Committee of the Uranium Institute was established to monitor continuously information and developments bearing on the uranium market and to publish from time to time reports giving its views on the supply and demand outlook. The last Uranium Institute supply and demand report was compiled at the beginning of 1979. Its main conclusions were that from 1979 to 1990 the flexibilities of the market were such as to offer adequate scope to producers and consumers of uranium to ensure a balance between supply and demand. Is that conclusion still valid one and a half years later. Some of the Supply and Demand Committee's more recent estimates are reported under the headings: reactor orders and cancellations; revised Institute forecasts of nuclear capacity; uranium supply; main implications of the new forecasts. (U.K.)

  14. Uranium 2009 resources, production and demand

    CERN Document Server

    Organisation for Economic Cooperation and Development. Paris

    2010-01-01

    With several countries currently building nuclear power plants and planning the construction of more to meet long-term increases in electricity demand, uranium resources, production and demand remain topics of notable interest. In response to the projected growth in demand for uranium and declining inventories, the uranium industry – the first critical link in the fuel supply chain for nuclear reactors – is boosting production and developing plans for further increases in the near future. Strong market conditions will, however, be necessary to trigger the investments required to meet projected demand. The "Red Book", jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, is a recognised world reference on uranium. It is based on information compiled in 40 countries, including those that are major producers and consumers of uranium. This 23rd edition provides a comprehensive review of world uranium supply and demand as of 1 January 2009, as well as data on global ur...

  15. The UFE Prospective scenarios for energy demand

    International Nuclear Information System (INIS)

    2013-01-01

    After an overview of the French energy consumption in 2011 (final energy consumption, distribution of CO 2 emissions related to energy consumption), this Power Point presentation proposes graphs and figures illustrating UFE's prospective scenarios for energy demand. The objective is to foresee energy demand in 2050, to study the impact of possible actions on energy demand, and to assess the impact on greenhouse gas emissions. Hypotheses relate to demographic evolution, economic growth, energy intensity evolution, energy efficiency, and use transfers. Factors of evolution of energy demand are discussed: relationship between demography and energy consumption, new uses of electricity (notably with TICs), relationship between energy intensity and economic growth. Actions on demand are discussed. The results of different scenarios of technical evolution are presented

  16. Option value of electricity demand response

    Energy Technology Data Exchange (ETDEWEB)

    Sezgen, Osman; Goldman, C.A. [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley CA 94720 (United States); Krishnarao, P. [Citigroup Energy Inc., 1301 Fannin St, Houston, TX 77002 (United States)

    2007-02-15

    As electricity markets deregulate and energy tariffs increasingly expose customers to commodity price volatility, it is difficult for energy consumers to assess the economic value of investments in technologies that manage electricity demand in response to changing energy prices. The key uncertainties in evaluating the economics of demand-response technologies are the level and volatility of future wholesale energy prices. In this paper, we demonstrate that financial engineering methodologies originally developed for pricing equity and commodity derivatives (e.g., futures, swaps, options) can be used to estimate the value of demand-response technologies. We adapt models used to value energy options and assets to value three common demand-response strategies: load curtailment, load shifting or displacement, and short-term fuel substitution-specifically, distributed generation. These option models represent an improvement to traditional discounted cash flow methods for assessing the relative merits of demand-side technology investments in restructured electricity markets. (author)

  17. Communication technologies for demand side management

    Energy Technology Data Exchange (ETDEWEB)

    Uuspaeae, P [VTT Energy, Espoo (Finland)

    1998-08-01

    The scope of this research is data communications for electric utilities, specifically for the purposes of Demand Side Management (DSM). Demand Side Management has the objective to change the customer`s end use of energy in a manner that benefits both the customer and the utility. For example, peak demand may be reduced, and the peak demand may be relocated to off peak periods. Thus additional investments in generation and network may be avoided. A number of Demand Side Management functions can be implemented if a communication system is available between the Electric Utility and the Customer. The total communication capacity that is needed, will depend on several factors, such as the functions that are chosen for DSM, and on the number and type of customers. Some functions may be handled with one-way communications, while some other functions need to have two-way communication

  18. Cointegration and the demand for gasoline

    Energy Technology Data Exchange (ETDEWEB)

    Bhaskara Rao, B. [University of Western Sydney, Sydney1797 (Australia); Rao, Gyaneshwar [University of the South Pacific (Fiji)

    2009-10-15

    Since the early 1970s, there has been a worldwide upsurge in the price of energy and in particular of gasoline. Therefore, demand functions for energy and its components like gasoline have received much attention. However, since confidence in the estimated demand functions is important for use in policy and forecasting, following [Amarawickrama, H.A., Hunt, L.C., 2008. Electricity demand for Sri Lanka: A time series analysis. Energy Economics 33, 724-739], this paper estimates the demand for gasoline is estimated with five alternative time series techniques with data from Fiji. Estimates with these alternative techniques are very close, and thus increase our confidence in them. We found that gasoline demand is both price and income inelastic. (author)

  19. Demand flexibility from residential heat pump

    DEFF Research Database (Denmark)

    Bhattarai, Bishnu Prasad; Bak-Jensen, Birgitte; Pillai, Jayakrishnan Radhakrishna

    2014-01-01

    Demand response (DR) is considered as a potentially effective tool to compensate generation intermittency imposed by renewable sources. Further, DR can instigate to offer optimum asset utilization and to avoid or delay the need for new infrastructure investment. Being a sizable load together...... with high thermal time constant, heat pumps (HP) can offer a great deal of flexibility in the future intelligent grids especially to compensate fluctuating generation. However, the HP flexibility is highly dependent on thermal demand profile, namely hot water and space heating demand. This paper proposes...... price based scheduling followed by a demand dispatch based central control and a local voltage based adaptive control, to realize HP demand flexibility. Two-step control architecture, namely local primary control encompassed by the central coordinative control, is proposed to implement...

  20. Competition with supply and demand functions

    International Nuclear Information System (INIS)

    Bolle, F.

    2001-01-01

    If economic agents have to determine in advance their supply or demand in reaction to different market prices we may assume that their strategic instruments are supply or demand functions. The best examples for such markets are the spot markets for electricity in England and Wales, in Chile, in New Zealand, in Scandinavia and perhaps elsewhere. A further example is computerized trading in stock markets, financial markets, or commodity exchanges. The functional form of equilibria is explicitly determined in this paper. Under a certain condition, equilibria exist for every finite spread of (stochastic) autonomous demand, i.e. demand from small, non-strategically acting consumers. Contrary to competition with supply functions alone, however, there is no tendency for market prices to converge to 0 if the spread of autonomous demand increases infinitely. Lower bounds of market prices can be computed instead

  1. Option value of electricity demand response

    International Nuclear Information System (INIS)

    Sezgen, Osman; Goldman, C.A.; Krishnarao, P.

    2007-01-01

    As electricity markets deregulate and energy tariffs increasingly expose customers to commodity price volatility, it is difficult for energy consumers to assess the economic value of investments in technologies that manage electricity demand in response to changing energy prices. The key uncertainties in evaluating the economics of demand-response technologies are the level and volatility of future wholesale energy prices. In this paper, we demonstrate that financial engineering methodologies originally developed for pricing equity and commodity derivatives (e.g., futures, swaps, options) can be used to estimate the value of demand-response technologies. We adapt models used to value energy options and assets to value three common demand-response strategies: load curtailment, load shifting or displacement, and short-term fuel substitution-specifically, distributed generation. These option models represent an improvement to traditional discounted cash flow methods for assessing the relative merits of demand-side technology investments in restructured electricity markets. (author)

  2. Oxygen Reduction on Platinum

    DEFF Research Database (Denmark)

    Nesselberger, Markus

    . The influence of the ion adsorption strength, which is observed in the “particle size studies” on the oxygen reduction rate on Pt/C catalysts, is further investigated under similar reaction conditions by infrared spectroscopy. The designed in situ electrochemical ATR-FTIR setup features a high level...... of instrument automation and online data treatment, and provides welldefined mass transport conditions enabling kinetic measurements. A modified electrochemical / spectroscopic interface is presented allowing the exclusive investigation of the Pt/C catalyst layer. Three types of potential dependent adsorption...... adsorption on Pt does not block the ORR directly. Instead, the onset of oxide formation with the concomitant conversion of the anion adsorbate layer is the decisive blocking mechanism....

  3. Reactive Oxygen Species

    DEFF Research Database (Denmark)

    Franchina, Davide G.; Dostert, Catherine; Brenner, Dirk

    2018-01-01

    T cells are a central component of defenses against pathogens and tumors. Their effector functions are sustained by specific metabolic changes that occur upon activation, and these have been the focus of renewed interest. Energy production inevitably generates unwanted products, namely reactive...... and transcription factors, influencing the outcome of the T cell response. We discuss here how ROS can directly fine-tune metabolism and effector functions of T cells....... oxygen species (ROS), which have long been known to trigger cell death. However, there is now evidence that ROS also act as intracellular signaling molecules both in steady-state and upon antigen recognition. The levels and localization of ROS contribute to the redox modeling of effector proteins...

  4. THE COMPETITIVE DEMANDS OF ELITE MALE RINK HOCKEY

    Directory of Open Access Journals (Sweden)

    Aladino Fernández

    2013-06-01

    Full Text Available The aim of this study was to simulate the activity pattern of rink hockey by designing a specific skate test (ST to study the energy expenditure and metabolic responses to this intermittent high-intensity exercise and extrapolate the results from the test to competition. Six rink hockey players performed, in three phases, the 20-metre multi-stage shuttle roller skate test, a tournament match and the ST. Heart rate was monitored in all three phases. Blood lactate, oxygen consumption, ventilation and respiratory exchange ratio were also recorded during the ST. Peak HR was 190.7±7.2 beats · min-1. There were no differences in peak HR between the three tests. Mean HR was similar between the ST and the match (86% and 87% of HRmax, respectively. Peak and mean ventilation averaged 111.0±8.8 L · min-1 and 70.3±14.0 L · min-1 (60% of VEmax, respectively. VO2max was 56.3±8.4 mL · kg-1 · min-1, and mean oxygen consumption was 40.9±7.9 mL · kg-1 · min-1 (70% of VO2max. Maximum blood lactate concentration was 7.2±1.3 mmol · L-1. ST yielded an energy expenditure of 899.1±232.9 kJ, and energy power was 59.9±15.5 kJ · min-1. These findings suggest that the ST is suitable for estimating the physiological demands of competitive rink hockey, which places a heavy demand on the aerobic and anaerobic systems, and requires high energy consumption.

  5. OXYGEN TRANSPORT CERAMIC MEMBRANES

    International Nuclear Information System (INIS)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2001-01-01

    Conversion of natural gas to liquid fuels and chemicals is a major goal for the Nation as it enters the 21st Century. Technically robust and economically viable processes are needed to capture the value of the vast reserves of natural gas on Alaska's North Slope, and wean the Nation from dependence on foreign petroleum sources. Technologies that are emerging to fulfill this need are all based syngas as an intermediate. Syngas (a mixture of hydrogen and carbon monoxide) is a fundamental building block from which chemicals and fuels can be derived. Lower cost syngas translates directly into more cost-competitive fuels and chemicals. The currently practiced commercial technology for making syngas is either steam methane reforming (SMR) or a two-step process involving cryogenic oxygen separation followed by natural gas partial oxidation (POX). These high-energy, capital-intensive processes do not always produce syngas at a cost that makes its derivatives competitive with current petroleum-based fuels and chemicals. This project has the following 6 main tasks: Task 1--Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. Task 2--Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. Task 3--Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. Task 4--Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. Task 5--Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. Task 6--Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques

  6. Characteristic of leachate at Alor Pongsu Landfill Site, Perak, Malaysia: A comparative study

    Science.gov (United States)

    Nor Farhana Zakaria, Siti; Aziz, Hamidi Abdul

    2018-04-01

    Leachate is a harmful by product generated from the landfill site. Leachate contains a high concentration of pollutant which can cause serious pollution to environmental. In this study, characteristics of leachate in Alor Pongsu Landfill Site (APLS) were monitored and analyzed according to the Standard Methods for the Examination of Water and Wastewater (2005). Composition in leachate at APLS was monitored for one year starting from January 2015 until January 2016. Nine parameters were monitored including color, chemical oxygen demand (COD), biological oxygen demand (BOD5), ammoniacal nitrogen (NH3-N), biodegradability ratio (BOD5/COD), temperature, dissolved oxygen (DO), total dissolved solid (TDS) and pH. Based on the analysis, Alor Pongsu Landfill leachate was categorized as stabilized landfill leachate by referring to the BOD5/COD < 0.1. Comparison with allowable discharge limits for leachate shows that most of parameters exceeded the standard discharge limitation. Thus, proper treatment is needed before leachate can be discharged to the environment.

  7. Province gets serious about demand management

    International Nuclear Information System (INIS)

    Anon

    2003-01-01

    Directives from the Minister to the Ontario Energy Board to review options for demand-side management and demand reduction activities, and discussion papers describing the policy framework needed to implement demand management, are indications of renewed interest by the provincial government in demand-side management of Ontario's electric power supply. This renewed interest comes on the hills of a 5.5 per cent increase in electricity use, a 33 per cent increase in imports, and consumption records broken in 10 of the last 12 months. A 117-page study was released in April by Navigant Consulting, entitled 'Demand response blueprint for Ontario' which estimates that if the Ontario market had 250 MW of additional demand response, customers providing the demand response would have saved $20 million by reducing their demand when HOEP was greater than $120/MWh, while other customers would have saved $170 million due to lower HOEP, and would have enjoyed greater reliability as a result of the increase in reserve margins. Other than price signals to induce customers to save, the Navigant report suggest paying customers not to consume during peak periods. The report estimates that such a policy could generate a total demand response of 350 MW and a $235 million reduction in revenue to generators. The Navigan report also includes a large number of detailed analysis and recommendations. One among them is for the extensive use of interval meters for customers with loads over 200 kW. The report tends to be critical of the recent price freeze ordered by the Ontario government, claiming that the freeze could increase consumption, making prices more volatile and increasing the cost to the government even more. Successful demand response programs from California, New York and the New England states are cited as examples for Ontario to emulate

  8. Coordination of Energy Efficiency and Demand Response

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, Charles; Reid, Michael; Levy, Roger; Silverstein, Alison

    2010-01-29

    This paper reviews the relationship between energy efficiency and demand response and discusses approaches and barriers to coordinating energy efficiency and demand response. The paper is intended to support the 10 implementation goals of the National Action Plan for Energy Efficiency's Vision to achieve all cost-effective energy efficiency by 2025. Improving energy efficiency in our homes, businesses, schools, governments, and industries - which consume more than 70 percent of the nation's natural gas and electricity - is one of the most constructive, cost-effective ways to address the challenges of high energy prices, energy security and independence, air pollution, and global climate change. While energy efficiency is an increasingly prominent component of efforts to supply affordable, reliable, secure, and clean electric power, demand response is becoming a valuable tool in utility and regional resource plans. The Federal Energy Regulatory Commission (FERC) estimated the contribution from existing U.S. demand response resources at about 41,000 megawatts (MW), about 5.8 percent of 2008 summer peak demand (FERC, 2008). Moreover, FERC recently estimated nationwide achievable demand response potential at 138,000 MW (14 percent of peak demand) by 2019 (FERC, 2009).2 A recent Electric Power Research Institute study estimates that 'the combination of demand response and energy efficiency programs has the potential to reduce non-coincident summer peak demand by 157 GW' by 2030, or 14-20 percent below projected levels (EPRI, 2009a). This paper supports the Action Plan's effort to coordinate energy efficiency and demand response programs to maximize value to customers. For information on the full suite of policy and programmatic options for removing barriers to energy efficiency, see the Vision for 2025 and the various other Action Plan papers and guides available at www.epa.gov/eeactionplan.

  9. Strategies for Demand Response in Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Watson, David S.; Kiliccote, Sila; Motegi, Naoya; Piette, Mary Ann

    2006-06-20

    This paper describes strategies that can be used in commercial buildings to temporarily reduce electric load in response to electric grid emergencies in which supplies are limited or in response to high prices that would be incurred if these strategies were not employed. The demand response strategies discussed herein are based on the results of three years of automated demand response field tests in which 28 commercial facilities with an occupied area totaling over 11 million ft{sup 2} were tested. Although the demand response events in the field tests were initiated remotely and performed automatically, the strategies used could also be initiated by on-site building operators and performed manually, if desired. While energy efficiency measures can be used during normal building operations, demand response measures are transient; they are employed to produce a temporary reduction in demand. Demand response strategies achieve reductions in electric demand by temporarily reducing the level of service in facilities. Heating ventilating and air conditioning (HVAC) and lighting are the systems most commonly adjusted for demand response in commercial buildings. The goal of demand response strategies is to meet the electric shed savings targets while minimizing any negative impacts on the occupants of the buildings or the processes that they perform. Occupant complaints were minimal in the field tests. In some cases, ''reductions'' in service level actually improved occupant comfort or productivity. In other cases, permanent improvements in efficiency were discovered through the planning and implementation of ''temporary'' demand response strategies. The DR strategies that are available to a given facility are based on factors such as the type of HVAC, lighting and energy management and control systems (EMCS) installed at the site.

  10. Mitochondrial Respiration and Oxygen Tension.

    Science.gov (United States)

    Shaw, Daniel S; Meitha, Karlia; Considine, Michael J; Foyer, Christine H

    2017-01-01

    Measurements of respiration and oxygen tension in plant organs allow a precise understanding of mitochondrial capacity and function within the context of cellular oxygen metabolism. Here we describe methods that can be routinely used for the isolation of intact mitochondria, and the determination of respiratory electron transport, together with techniques for in vivo determination of oxygen tension and measurement of respiration by both CO 2 production and O 2 consumption that enables calculation of the respiratory quotient [CO 2 ]/[O 2 ].

  11. Oxygen-reducing catalyst layer

    Science.gov (United States)

    O'Brien, Dennis P [Maplewood, MN; Schmoeckel, Alison K [Stillwater, MN; Vernstrom, George D [Cottage Grove, MN; Atanasoski, Radoslav [Edina, MN; Wood, Thomas E [Stillwater, MN; Yang, Ruizhi [Halifax, CA; Easton, E Bradley [Halifax, CA; Dahn, Jeffrey R [Hubley, CA; O'Neill, David G [Lake Elmo, MN

    2011-03-22

    An oxygen-reducing catalyst layer, and a method of making the oxygen-reducing catalyst layer, where the oxygen-reducing catalyst layer includes a catalytic material film disposed on a substrate with the use of physical vapor deposition and thermal treatment. The catalytic material film includes a transition metal that is substantially free of platinum. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.

  12. Oxygen potentials of transuranium oxides

    International Nuclear Information System (INIS)

    Haruyoshi Otobe; Mituso Akabori; Arai Yasuo; Kazuo Minato

    2008-01-01

    The oxygen potentials of pyrochlore-type Pu 2 Zr 2 O 7+y , fluorite-type (Pu 0.5 Zr 0.5 )O 2-x and AmO 2-x have been measured by the electromotive force (EMF) method with a zirconia solid-electrolyte. The oxygen potentials of these oxides were reviewed. The phase relations, microstructure, equilibrium state of these oxides were discussed, referring to the isothermal curve of the oxygen potentials. (authors)

  13. Can Oxygen Set Thermal Limits in an Insect and Drive Gigantism?

    Science.gov (United States)

    Verberk, Wilco C. E. P.; Bilton, David T.

    2011-01-01

    Background Thermal limits may arise through a mismatch between oxygen supply and demand in a range of animal taxa. Whilst this oxygen limitation hypothesis is supported by data from a range of marine fish and invertebrates, its generality remains contentious. In particular, it is unclear whether oxygen limitation determines thermal extremes in tracheated arthropods, where oxygen limitation may be unlikely due to the efficiency and plasticity of tracheal systems in supplying oxygen directly to metabolically active tissues. Although terrestrial taxa with open tracheal systems may not be prone to oxygen limitation, species may be affected during other life-history stages, particularly if these rely on diffusion into closed tracheal systems. Furthermore, a central role for oxygen limitation in insects is envisaged within a parallel line of research focussing on insect gigantism in the late Palaeozoic. Methodology/Principal Findings Here we examine thermal maxima in the aquatic life stages of an insect at normoxia, hypoxia (14 kPa) and hyperoxia (36 kPa). We demonstrate that upper thermal limits do indeed respond to external oxygen supply in the aquatic life stages of the stonefly Dinocras cephalotes, suggesting that the critical thermal limits of such aquatic larvae are set by oxygen limitation. This could result from impeded oxygen delivery, or limited oxygen regulatory capacity, both of which have implications for our understanding of the limits to insect body size and how these are influenced by atmospheric oxygen levels. Conclusions/Significance These findings extend the generality of the hypothesis of oxygen limitation of thermal tolerance, suggest that oxygen constraints on body size may be stronger in aquatic environments, and that oxygen toxicity may have actively selected for gigantism in the aquatic stages of Carboniferous arthropods. PMID:21818347

  14. Can oxygen set thermal limits in an insect and drive gigantism?

    Directory of Open Access Journals (Sweden)

    Wilco C E P Verberk

    Full Text Available BACKGROUND: Thermal limits may arise through a mismatch between oxygen supply and demand in a range of animal taxa. Whilst this oxygen limitation hypothesis is supported by data from a range of marine fish and invertebrates, its generality remains contentious. In particular, it is unclear whether oxygen limitation determines thermal extremes in tracheated arthropods, where oxygen limitation may be unlikely due to the efficiency and plasticity of tracheal systems in supplying oxygen directly to metabolically active tissues. Although terrestrial taxa with open tracheal systems may not be prone to oxygen limitation, species may be affected during other life-history stages, particularly if these rely on diffusion into closed tracheal systems. Furthermore, a central role for oxygen limitation in insects is envisaged within a parallel line of research focussing on insect gigantism in the late Palaeozoic. METHODOLOGY/PRINCIPAL FINDINGS: Here we examine thermal maxima in the aquatic life stages of an insect at normoxia, hypoxia (14 kPa and hyperoxia (36 kPa. We demonstrate that upper thermal limits do indeed respond to external oxygen supply in the aquatic life stages of the stonefly Dinocras cephalotes, suggesting that the critical thermal limits of such aquatic larvae are set by oxygen limitation. This could result from impeded oxygen delivery, or limited oxygen regulatory capacity, both of which have implications for our understanding of the limits to insect body size and how these are influenced by atmospheric oxygen levels. CONCLUSIONS/SIGNIFICANCE: These findings extend the generality of the hypothesis of oxygen limitation of thermal tolerance, suggest that oxygen constraints on body size may be stronger in aquatic environments, and that oxygen toxicity may have actively selected for gigantism in the aquatic stages of Carboniferous arthropods.

  15. Demand-Side Flexibility for Energy Transitions: Ensuring the Competitive Development of Demand Response Options

    OpenAIRE

    Nursimulu, Anjali; Florin, Marie-Valentine; Vuille, François

    2015-01-01

    This report provides an overview of the current debates about demand response development, focusing primarily on Europe, with some comparisons to the United States. ‘Demand response’ includes strategies that involve end-use customers adapting or altering their electricity demand in response to grid conditions or market prices. It is viewed as a multi-purpose power-system resource that enhances the energy system’s capacity to cope with increasing demand, rising costs of conventional transmissi...

  16. Estimation of Forest Products Demand as an Intermediary Function

    OpenAIRE

    Andersson, A.E.

    1984-01-01

    In this article the problem of demand forecasting is discussed from a quantitative point of view. It is shown that an intermediate demand approach is preferable to the common final demand procedures of forest product demand studies.

  17. Oxygen diffusion and oxygen effect in tumor tissue

    International Nuclear Information System (INIS)

    Eissa, H.M.; Hehn, G.

    1979-06-01

    The diffusion of oxygen in tumor cords of bronchus carcinoma of the lung have been studied with refined computer methods for solving the diffusion equation in axis symmetric tumor structures. In this tumor configuration we may find three different regions consisting of euoxic cells, hypoxic tumor cells and necrotic parts. In the case of oxygen supply from a capillary inside a cylinder of tumor tissue with radius 200 μm or in a tumor cord of radius 300 μm with oxygen supply by capillaries outside, we get a relation of well oxygenated cells to hypoxic cells approximately as 1:8 or as 1:1.1 respectively. Of course most of the tumor cords observed in histological slices have smaller diameters, so that an average of approximately 20% hypoxic cells can be assumed. Based on the work of Ardenne, the diffusion of oxygen and glucose in a tumor of type DS-carcinosarcom has been investigated in both intact tumor and tumor treated with ionizing radiation. We can show that a strong reoxygenation effect takes place in that the well supplied regions may increase in some tumor configurations up to a factor of four by volume. The biological consequences of the oxygen pressure determined in tumor cells are discussed in detail. The investigation of oxygen diffusion in the intercapillary tumor region should give a quantitative physical basis for considering the oxygen effect with the aim to explain the advantages of neutron therapy against conventional radiotherapy. (orig./MG) [de

  18. Integration of oxygen membranes for oxygen production in cement plants

    DEFF Research Database (Denmark)

    Puig Arnavat, Maria; Søgaard, Martin; Hjuler, Klaus

    2015-01-01

    The present paper describes the integration of oxygen membranes in cement plants both from an energy, exergy and economic point of view. Different configurations for oxygen enrichment of the tertiary air for combustion in the pre-calciner and full oxy-fuel combustion in both pre-calciner and kiln...

  19. Dynamic inventory rationing strategies for inventory systems with two demand classes, Poisson demand and backordering

    NARCIS (Netherlands)

    Teunter, Ruud H.; Haneveld, Willem K. Klein

    2008-01-01

    We study inventory systems with two demand classes (critical and non-critical), Poisson demand and backordering. We analyze dynamic rationing strategies where the number of items reserved for critical demand depends on the remaining time until the next order arrives. Different from results in the

  20. History of demand side management and classification of demand response control schemes

    NARCIS (Netherlands)

    Lampropoulos, I.; Kling, W.L.; Ribeiro, P.F.; Berg, van den J.

    2013-01-01

    The scope of this paper is to provide a review on the topic of demand side management. A historical overview provides a critical insight to applied cases, while the discovery of new evidence calls for reconsideration of the design of demand response control schemes. The developments at the demand