210Po and 210Pb concentration of cigarettes traded in Hungary and their estimated dose contribution due to smoking

International Nuclear Information System (INIS)

Kovacs, Tibor; Somlai, Janos; Nagy, Katalin; Szeiler, Gabor

2007-01-01

It is known that tobacco leaves may contain 210 Pb and 210 Po in significant concentrations. The cumulative alpha-radiation dose due to the radioactive content of inhaled cigarette smoke and the increasing number of lung cancer cases explain the importance of the investigation. The present study investigated the activity concentrations of these two radionuclides in 29 Hungarian cigarette samples. The relation between 210 Po/ 210 Pb activity and nicotine/tar content of these cigarettes was also examined. 210 Po was determined by alpha spectrometry using a PIPS detector after chemical leaching and spontaneous deposition of 210 Po on a high nickel-content (25%) stainless steel disk. The 210 Pb activity was calculated from the 210 Po originated from the decay of 210 Pb after a waiting period of eight months. The 210 Po activity concentrations of the measured types of cigarettes ranged from 10.0 to 33.5 mBq/cigarette, and the activity of 210 Pb varied from 9.6 to 32.5 mBq/cigarette. The average annual committed effective dose is estimated to be 185.6±70.6μSv/y and 58.7±22.7μSv/y due to cigarette smoking (20 cigarettes/day) for 210 Po and 210 Pb, respectively

Concentration changes due to cathodic protection

NARCIS (Netherlands)

Gellings, P.J.

1978-01-01

By solving the appropriate diffusion equations the concentration changes are calculated in the environment of underground structures protected cathodically. It is shown that these changes are negligible under all practical circumstances.

Characterization of high concentration dust generator

International Nuclear Information System (INIS)

Shimura, Toichiro; Yokochi, Akira

1999-01-01

This paper describes the development of fluidized bed type high concentration dust generator that keeps for long period dust concentration range of about 10 mg/m 3 for the study of working place monitoring system and evaluation of respirator. The generator is keeping constant powder in fluidized bed for keeping the dust concentration. It is necessary to keep constant feeding rate of powder in order to keep the quantity of dust in the fluidized bed. Our generator enables to obtain constant feeding rate by a screw feeder and by using mixed powder with fluidising particles (glass beads) before feeding. The generator produces high concentration dust of 11.3 mg/m 3 ± 1.0 mg/m 3 for about 5 hours and keeps the dust size 4.2-4.6 μm in mass median aerodynamic diameter with reasonable reproducibility. (author)

Nitrogen concentration profiles in oxy-nitrited high-speed steel

International Nuclear Information System (INIS)

Barcz, A.; Turos, A.; Wielunski, L.

1976-01-01

Nuclear microanalysis has been applied for the determination of in-depth concentration profiles of nitrogen in oxy-nitrided high-speed steel. The concentration profiles were deduced from measurements of the nitrogen content, determined by means of the 14 N(d,α) 12 C reaction for the set of initially identical samples after the removal of surface layers of sequentially increasing thicknesses. The 1.2 MeV deuterons were obtained from the Institute of Nuclear Research Van de Graaf accelerator LECH. The α-particles produced in the 14 N(d,α) 12 C reaction were detected by means of silicon surface barrier detector mounted at 150 deg C. Strong blocking of the nitrogen diffusion due to the presence of oxygen has been observed. The accuracy of nitrogen detection is of the order of 5% for nitrogen-rich regions and 10% for the matrix. However, the local non-uniformity of the steel may cause a spread of about 20% of the measured values. (T.G.)

Electrical injuries due to railway high tension cables.

Science.gov (United States)

Reichl, M; Kay, S

1985-08-01

We have noted a large number of young boys being admitted to our Unit with burns due to railway high tension cables. On review of these cases we have noted: most of the burns were due to arcing, there is a high level of ignorance among the population at risk. We propose some ways of preventing these injuries.

Multijunction Photovoltaic Technologies for High-Performance Concentrators: Preprint

Energy Technology Data Exchange (ETDEWEB)

McConnell, R.; Symko-Davies, M.

2006-05-01

Multijunction solar cells provide high-performance technology pathways leading to potentially low-cost electricity generated from concentrated sunlight. The National Center for Photovoltaics at the National Renewable Energy Laboratory has funded different III-V multijunction solar cell technologies and various solar concentration approaches. Within this group of projects, III-V solar cell efficiencies of 41% are close at hand and will likely be reported in these conference proceedings. Companies with well-developed solar concentrator structures foresee installed system costs of $3/watt--half of today's costs--within the next 2 to 5 years as these high-efficiency photovoltaic technologies are incorporated into their concentrator photovoltaic systems. These technology improvements are timely as new large-scale multi-megawatt markets, appropriate for high performance PV concentrators, open around the world.

Trends in Pinus ponderosa foliar pigment concentration due to chronic exposure of ozone and acid rain

International Nuclear Information System (INIS)

Neuman, L.; Houpis, J.; Anderson, P.

1991-01-01

To determine the effects of ozone and acid rain on mature Ponderosa pine trees, Lawrence Livermore National Lab. has collaborated with University of California Berkeley, University of California Davis, California State University Chico, and the US Forest Service at the latter's Chico Tree Improvement Center. Foliar tissue from mature grafted scions of Pinus ponderosa were exposed to two times ambient ozone for ten months and to acid rain (3.0 pH) weekly for 10 weeks using branch exposure chambers. Pigment extracts were analyzed spectrophotometrically for concentrations of chlorophylls a and b, and carotenoid pigments, at 662 nm, 644 nm, and 470 nm, respectively. Pigment concentrations were expressed on a surface area basis. Preliminary results revealed that chlorophyll a showed a downward trend due to the ozone treatment. Acid rain caused no effects on these three pigments, however, chlorophyll b showed an upward trend due to the interaction of ozone and acid rain. The carotenoid pigments showed no changes due to the treatments either singly, or in combination

Highly Stable Operation of Lithium Metal Batteries Enabled by the Formation of a Transient High Concentration Electrolyte Layer

Energy Technology Data Exchange (ETDEWEB)

Zheng, Jianming; Yan, Pengfei; Mei, Donghai; Engelhard, Mark H.; Cartmell, Samuel S.; Polzin, Bryant; Wang, Chong M.; Zhang, Jiguang; Xu, Wu

2016-02-08

Lithium (Li) metal has been extensively investigated as an anode for rechargeable battery applications due to its ultrahigh specific capacity and the lowest redox potential. However, significant challenges including dendrite growth and low Coulombic efficiency are still hindering the practical applications of rechargeable Li metal batteries. Here, we demonstrate that long-term cycling of Li metal batteries can be realized by the formation of a transient high concentration electrolyte layer near the surface of Li metal anode during high rate discharge process. The highly concentrated Li+ ions in this transient layer will immediately solvate with the available solvent molecules and facilitate the formation of a stable and flexible SEI layer composed of a poly(ethylene carbonate) framework integrated with other organic/inorganic lithium salts. This SEI layer largely suppresses the corrosion of Li metal anode by free organic solvents and enables the long-term operation of Li metal batteries. The fundamental findings in this work provide a new direction for the development and operation of Li metal batteries that could be operated at high current densities for a wide range of applications.

Vitamin E concentrations in adults with HIV/AIDS on highly active antiretroviral therapy.

Science.gov (United States)

Itinoseki Kaio, Daniella J Itinoseki; Rondó, Patricia Helen C; Luzia, Liania Alves; Souza, José Maria P; Firmino, Aline Vale; Santos, Sigrid Sousa

2014-09-15

HIV/AIDS patients are probably more predisposed to vitamin E deficiency, considering that they are more exposed to oxidative stress. Additionally, there are an extensive number of drugs in the highly active antiretroviral therapy (HAART) regimens that may interfere with vitamin E concentrations. The objective of this study was to compare serum concentrations of alpha-tocopherol in 182 HIV/AIDS patients receiving different HAART regimens. The patients were divided into three groups according to regimen: nucleoside analog reverse-transcriptase inhibitors (NRTIs) + non-nucleoside analog reverse-transcriptase inhibitors (NNRTIs); NRTIs + protease inhibitors + ritonavir; NRTIs + other classes. Alpha-tocopherol was assessed by high-performance liquid chromatography. Multiple linear regression analysis was used to evaluate the effects of HAART regimen, time of use, and compliance with the regimen on alpha-tocopherol concentrations. Alpha-tocopherol concentrations were on average 4.12 μmol/L lower for the NRTIs + other classes regimen when compared to the NRTIs + NNRTIs regimen (p = 0.037). A positive association (p < 0.001) was observed between alpha-tocopherol and cholesterol concentrations, a finding due, in part, to the relationship between liposoluble vitamins and lipid profile. This study demonstrated differences in alpha-tocopherol concentrations between patients using different HAART regimens, especially regimens involving the use of new drugs. Long-term prospective cohort studies are needed to monitor vitamin E status in HIV/AIDS patients since the beginning of treatment.

Generating false negatives and false positives for As and Mo concentrations in groundwater due to well installation.

Science.gov (United States)

Wallis, Ilka; Pichler, Thomas

2018-08-01

Groundwater monitoring relies on the acquisition of 'representative' groundwater samples, which should reflect the ambient water quality at a given location. However, drilling of a monitoring well for sample acquisition has the potential to perturb groundwater conditions to a point that may prove to be detrimental to the monitoring objective. Following installation of 20 monitoring wells in close geographic proximity in central Florida, opposing concentration trends for As and Mo were observed. In the first year after well installation As and Mo concentrations increased in some wells by a factor of 2, while in others As and Mo concentrations decreased by a factor of up to 100. Given this relatively short period of time, a natural change in groundwater composition of such magnitude is not expected, leaving well installation itself as the likely cause for the observed concentration changes. Hence, initial concentrations were identified as 'false negatives' if concentrations increased with time or as 'false positives' if concentrations decreased. False negatives were observed if concentrations were already high, i.e., the As or Mo were present at the time of drilling. False positives were observed if concentrations were relatively lower, i.e., As or Mo were present at low concentrations of approximately 1 to 2μg/L before drilling, but then released from the aquifer matrix as a result of drilling. Generally, As and Mo were present in the aquifer matrix in either pyrite or organic matter, both of which are susceptible to dissolution if redox conditions change due to the addition of oxygen. Thus, introduction of an oxidant into an anoxic aquifer through use of an oxygen saturated drilling fluid served as the conceptual model for the trends where concentrations decreased with time. Mixing between drilling fluid and groundwater (i.e., dilution) was used as the conceptual model for scenarios where increasing trends were observed. Conceptual models were successfully tested

Introduction of high oxygen concentrations into silicon wafers by high-temperature diffusion

International Nuclear Information System (INIS)

Casse, G.; Glaser, M.; Lemeilleur, F.; Ruzin, A.; Wegrzecki, M.

1999-01-01

The tolerance of silicon detectors to hadron irradiation can be improved by the introduction of a high concentration of oxygen into the starting material. High-resistivity Floating-Zone (FZ) silicon is required for detectors used in particle physics applications. A significantly high oxygen concentration (>10 17 atoms cm -3 ) cannot readily be achieved during the FZ silicon refinement. The diffusion of oxygen at elevated temperatures from a SiO 2 layer grown on both sides of a silicon wafer is a simple and effective technique to achieve high and uniform concentrations of oxygen throughout the bulk of a 300 μm thick silicon wafer

Reactive Transport Modeling Investigation of High Dissolved Sulfide Concentrations in Sedimentary Basin Rocks

Science.gov (United States)

Xie, M.; Mayer, U. K.; MacQuarrie, K. T. B.

2017-12-01

Water with total dissolved sulfide in excess of 1 mmol L-1is widely found in groundwater at intermediate depths in sedimentary basins, including regions of the Michigan basin in southeastern Ontario, Canada. Conversely, at deeper and shallower depths, relatively low total dissolved sulfide concentrations have been reported. The mechanisms responsible for the occurrence of these brackish sulfide-containing waters are not fully understood. Anaerobic microbial sulfate reduction is a common process resulting in the formation of high sulfide concentrations. Sulfate reduction rates depend on many factors including the concentration of sulfate, the abundance of organic substances, redox conditions, temperature, salinity and the species of sulfate reducing bacteria (SRB). A sedimentary basin-specific conceptual model considering the effect of salinity on the rate of sulfate reduction was developed and implemented in the reactive transport model MIN3P-THCm. Generic 2D basin-scale simulations were undertaken to provide a potential explanation for the dissolved sulfide distribution observed in the Michigan basin. The model is 440 km in the horizontal dimension and 4 km in depth, and contains fourteen sedimentary rock units including shales, sandstones, limestones, dolostone and evaporites. The main processes considered are non-isothermal density dependent flow, kinetically-controlled mineral dissolution/precipitation and its feedback on hydraulic properties, cation exchange, redox reactions, biogenic sulfate reduction, and hydromechanical coupling due to glaciation-deglaciation events. Two scenarios were investigated focusing on conditions during an interglacial period and the transient evolution during a glaciation-deglaciation cycle. Inter-glaciation simulations illustrate that the presence of high salinity brines strongly suppress biogenic sulfate reduction. The transient simulations show that glaciation-deglaciation cycles can have an impact on the maximum depth of

An assessment method of dose equivalent due to indoor 220Rn progeny by using 220Rn concentration measured at a 20 cm distance from wall

International Nuclear Information System (INIS)

Iida, T.; Ikebe, Y.; Okamoto, K.; Guo, Q.; Yamasaki, T.

1996-01-01

A pair of passive cup monitors with a different air exchange openings was developed for measuring simultaneously 222 Rn and 220 Rn concentrations. Indoor 220 Rn concentrations were very high in traditional Japanese dwellings with soil walls. The 220 Rn concentration decreases exponentially with the distance from wall. The effective diffusion coefficient of 220 Rn in dwelling and the exhalation rate of 220 Rn from wall were evaluated from the distribution of the 220 Rn concentrations. Then, indoor 220 Rn progeny concentration could be estimated from the 220 Rn concentration at a 20 cm distance from wall. From the results of the surveys. the average annual effective dose equivalent due to 220 Rn progeny was expected to be 0.67 mSv/year in the traditional Japanese dwellings. (author)

Extremely high concentration of folates in premature newborns.

Science.gov (United States)

Zikavska, T; Brucknerova, I

2014-01-01

Extremely high concentration of folates in premature newborns: case reports. Folates are a group of water soluble compounds, which are important for metabolic processes in human body. These are important during periods of rapid cell growth. The most accurate indicator of long-term folate level status in the body is the determination of red blood cell (RBC) folate concentrations. The optimal level of RBC folate is not known in neonatal period. Authors discuss the reasons for extremely high level of RBC folate concentrations. In our work we present the cases of two premature newborns with extremely high level of RBC folate concentrations, which were analyzed immunochemically on the first day of life and after six weeks of life. In both cases we measured RBC folate concentrations on the 1st day of life. After 6 weeks we found extremely high RBC folate concentration level (5516.67 ng/ml) in the first case after RBC transfusions. In second case after two months of life the RBC folate concentration level was doubled (2335.1 ng/ml) until 24 hours after RBC transfusion compared to levels after birth. The normal range of RBC folate values vary in newborns. The upper limit of daily dose of folic acid in pregnancy and neonatal period is not known. On the other hand it is an easily excreted water-soluble vitamin but in premature newborn it can lead to the disruption of metabolic balance and slow its degradation. Some factors can have an impact on RBC folate concentration. Blood transfusion can be one of the main influences on RBC folate concentration. To clarify these mechanisms further studies are required (Ref. 29).

Activity concentration and population dose from 226Ra due to consumption of dietary components

International Nuclear Information System (INIS)

Wagh, S.S.; Patra, A.K.; Ravi, P.M.; Sarkar, P.K.

2012-01-01

226 Ra (T 1/2 = 1620 years, α-energy 4.78 MeV, 4.59 MeV, γ-energy 186 keV), a product of natural uranium decay series, is abundantly observed in natural environment. Radium, along with its homologue calcium, an essential element in the plant system, is absorbed from the soil by plants and gets redistributed. within different parts of the plants. Because of the long half-life of 226 Ra, it gets accumulated in the human body for along time. The hazard due to ingestion of 226 Ra dissolved in water is reported to be about 40 times higher than that of 90 Sr. This paper deals with the concentration of 226 Ra in different dietary components and ingestion dose from 226 Ra due to consumption of dietary components. Internal radiation exposure to non-human biota due to 226 Ra is also discussed

Stress concentration effects in high pressure components

International Nuclear Information System (INIS)

Aller, J.E.

1990-01-01

This paper examines the stress concentration effects of sideholes in thick walled, high pressure cylinders. It has been shown that the theoretical stress concentration factor at the intersection of a small crossbore in a closed end, thick walled cylinder varies between 3.0 and 4.0. Tests have shown that this effect can be greatly reduced in practice by carefully radiusing the bore intersection and autofrettaging the cylinder. It has also been shown that the minimum stress concentration factor occurs when the main bore and sidehole or crossbore have the same diameter, and the radius of the intersection is approximately equal to the sidehole radius. When the bore and sidehole intersection angle decreases from 90 degrees, the stress concentration factor increases significantly. Knowledge of these fundamental relationships can be used in maintaining, as well ad designing, high pressure equipment

Case study of elevated layers of high sulfate concentration

International Nuclear Information System (INIS)

McNaughton, D.J.; Orgill, M.M.

1979-01-01

During studies in August 1976 that were part of the Multi-State Atmospheric Power Production Pollutant Study (MAP3S), Alkezweeny et al., (1977) noted that in the Milwaukee urban plume, layers of relatively high sulfate concentrations occurred at high altitudes with respect to the boundary layer. This paper represents a progress report on studies undertaken to investigate possible causes for a bimodel vertical profile of sulfate concentrations. Data presented by Alkezweeny et al., (1977) serve as a basis for this study. Data from August 23, 1976, and August 24, 1978, indicate concentrations relatively high in sulfate, at 1000 and 6000 ft, respectively, with lower concentrations at lower altitudes. Concentrations of trace metals also indicate no peaks in the vertical concentration profiles above the surface. Initial studies of the high, elevated sulfate concentrations have centered on the August 23 measurements taken over southeast Wisconsin using synoptic data from the national weather service, emissions data from the national emissions data bank system (EPA), air quality data from the national air surveillance network (EPA), and satellite photographs from the EROS Data Center

Acetate biodegradation by anaerobic microorganisms at high pH and high calcium concentration

International Nuclear Information System (INIS)

Yoshida, Takahiro

2011-01-01

Acetate biodegradation at a high pH and a high calcium concentration was examined to clarify the effect of bacterial activity on the migration of organic 14 C compounds in cementitious repositories. Tamagawa river sediment or Teganuma pond sediment was anaerobically cultured with 5 mM acetate and 10 mM nitrate at pH 9.5-12 at 30 o C. After 20 and 90 days, the acetate concentration of the culture medium was analyzed and found to have decreased below 5 mM at pH ≤ 11. On the other hand, it did not decrease when either sediment was incubated in the absence of nitrate. These results suggest that nitrate-reducing bacteria can biodegrade acetate under more alkaline conditions than the reported pH range in which nitrate-reducing bacteria can exhibit activity. Acetate biodegradation was also examined at a high calcium concentration. Sediments were anaerobically cultured at pH 9.5 with 5 mM acetate and 10 mM nitrate in solution, equilibrated with ordinary Portland cement hydrate, in which the Ca concentration was 14.6 mM. No decrease in acetate concentration after incubation of the sediments was observed, nor was it lower than in the absence of cementitious composition, suggesting that kinetics of acetate biodegradation by anaerobic microorganisms is lowered by a high Ca concentration. - Research highlights: → Acetate biodegradation at a high pH and a high calcium concentration was examined to clarify the effect of bacterial activity on the migration of organic 14 C compounds in cementitious repositories. → Nitrate-reducing bacteria can biodegrade acetate at pH ≤ 11. → Kinetics of acetate biodegradation by anaerobic microorganisms might be lowered by a high Ca concentration.

Ozone concentrations at a selected high-elevation forest site downwind Mexico City

Science.gov (United States)

Torres-JArdon, R.

2013-05-01

July to September. Episodes of high concentrations occurred mainly during the dry warm months. Most of the year, nocturnal ozone levels were higher than those registered in the urban area due to the PMH altitude. As a great part of the mountain terrain regularly is above the nocturnal mixing layer formed each day on the valley floor, the ozone remanent levels above this layer in the mountains are kept isolated from urban NOx emissions generated at night. An evaluation of the AOT40 indicator shows that the forest zone is under a strong risk due to ozone pollution. A preliminary analysis of several ozone events in the PNMH shows the suppression of the diel peak, suggesting that a stratospheric intrusion of ozone occurs frequently in high-elevation sites surrounding MCMA.

{sup 210}Po and {sup 210}Pb concentration of cigarettes traded in Hungary and their estimated dose contribution due to smoking

Energy Technology Data Exchange (ETDEWEB)

Kovacs, Tibor [Department of Radiochemistry, University of Pannonia, P.O. Box 158, H-8201 Veszprem (Hungary)], E-mail: kt@almos.vein.hu; Somlai, Janos [Department of Radiochemistry, University of Pannonia, P.O. Box 158, H-8201 Veszprem (Hungary); Nagy, Katalin [Department of Rheumatology, Markhot F. Heves County Hospital, Szechenyi ut 27, H-3300 Eger (Hungary); Szeiler, Gabor [Department of Radiochemistry, University of Pannonia, P.O. Box 158, H-8201 Veszprem (Hungary)

2007-11-15

It is known that tobacco leaves may contain {sup 210}Pb and {sup 210}Po in significant concentrations. The cumulative alpha-radiation dose due to the radioactive content of inhaled cigarette smoke and the increasing number of lung cancer cases explain the importance of the investigation. The present study investigated the activity concentrations of these two radionuclides in 29 Hungarian cigarette samples. The relation between {sup 210}Po/{sup 210}Pb activity and nicotine/tar content of these cigarettes was also examined. {sup 210}Po was determined by alpha spectrometry using a PIPS detector after chemical leaching and spontaneous deposition of {sup 210}Po on a high nickel-content (25%) stainless steel disk. The {sup 210}Pb activity was calculated from the {sup 210}Po originated from the decay of {sup 210}Pb after a waiting period of eight months. The {sup 210}Po activity concentrations of the measured types of cigarettes ranged from 10.0 to 33.5 mBq/cigarette, and the activity of {sup 210}Pb varied from 9.6 to 32.5 mBq/cigarette. The average annual committed effective dose is estimated to be 185.6{+-}70.6{mu}Sv/y and 58.7{+-}22.7{mu}Sv/y due to cigarette smoking (20 cigarettes/day) for {sup 210}Po and {sup 210}Pb, respectively.

Changes of electronic structure of SnTe due to high concentration of Sn vacancies

International Nuclear Information System (INIS)

Masek, J.; Nuzhnyj, D.N.

1997-01-01

Non-stoichiometric Sn 1-y Te is a strongly degenerated n-type semiconductor. This is important for understanding unusual features of magnetic behaviour of Sn 1-x Gd x Te where the relative positions of the Fermi energy and the atomic d-level of Gd govern the exchange coupling.The influence of the Sn vacancies on the band structure cannot be neglect if their concentration reaches a few atomic percent. We address this problem by using a tight-binding coherent potential approach and show that although the character of the bands remains unchanged, they are modified so that ε d can come out above the heavy-hole band. (author)

Bovine Mammary Nutrigenomics and Changes in the Milk Composition due to Rapeseed or Sunflower Oil Supplementation of High-Forage or High-Concentrate Diets.

Science.gov (United States)

Leroux, Christine; Bernard, Laurence; Faulconnier, Yannick; Rouel, Jacques; de la Foye, Anne; Domagalski, Jordann; Chilliard, Yves

2016-01-01

Fatty acid (FA) composition plays a crucial role in milk nutritional quality. Despite the known nutritional regulation of ruminant milk composition, the overall mammary mechanisms underlying this regulation are far from being understood. The aim of our study was to determine nutritional regulation of mammary transcriptomes in relation to the cow milk composition. Twelve cows received diets differing in the forage-to-concentrate ratio [high forage (HF) and low forage (LF)] supplemented or not with lipids [HF with whole intact rapeseeds (RS) and LF sunflower oil (SO)] in a 4 × 4 Latin square design. Milk production and FA composition were determined. The gene expression profile was studied using RT-qPCR and a bovine microarray. Our results showed a higher amplitude of milk composition and mammary transcriptome responses to lipid supplementation with the LF-SO compared with the LF diet than with the HF-RS compared with the HF diet. Forty-nine differentially expressed genes, including genes involved in lipid metabolism, were identified with LF-SO versus LF, whereas RS supplementation to the HF diet did not affect the mammary transcriptome. This study highlights different responses to lipid supplementation of milk production and composition and mammary transcriptomes depending on the nature of lipid supplementation and the percentage of dietary concentrate. © 2016 S. Karger AG, Basel.

Effects of high nitrogen concentrations on the growth of submersed macrophytes at moderate phosphorus concentrations.

Science.gov (United States)

Yu, Qing; Wang, Hong-Zhu; Li, Yan; Shao, Jian-Chun; Liang, Xiao-Min; Jeppesen, Erik; Wang, Hai-Jun

2015-10-15

Eutrophication of lakes leading to loss of submersed macrophytes and higher turbidity is a worldwide phenomenon, attributed to excessive loading of phosphorus (P). However, recently, the role of nitrogen (N) for macrophyte recession has received increasing attention. Due to the close relationship between N and P loading, disentanglement of the specific effects of these two nutrients is often difficult, and some controversy still exists as to the effects of N. We studied the effects of N on submersed macrophytes represented by Vallisneria natans (Lour.) Hara in pots positioned at three depths (0.4 m, 0.8 m, and 1.2 m to form a gradient of underwater light conditions) in 10 large ponds having moderate concentrations of P (TP 0.03 ± 0.04 mg L(-1)) and five targeted concentrations of total nitrogen (TN) (0.5, 2, 10, 20, and 100 mg L(-1)), there were two ponds for each treatment. To study the potential shading effects of other primary producers, we also measured the biomass of phytoplankton (ChlaPhyt) and periphyton (ChlaPeri) expressed as chlorophyll a. We found that leaf length, leaf mass, and root length of macrophytes declined with increasing concentrations of TN and ammonium, while shoot number and root mass did not. All the measured growth indices of macrophytes declined significantly with ChlaPhyt, while none were significantly related to ChlaPeri. Neither ChlaPhyt nor ChlaPeri were, however, significantly negatively related to the various N concentrations. Our results indicate that shading by phytoplankton unrelated to the variation in N loading and perhaps toxic stress exerted by high nitrogen were responsible for the decline in macrophyte growth. Copyright © 2015 Elsevier Ltd. All rights reserved.

High indoor radon concentrations in some Swedish waterworks

International Nuclear Information System (INIS)

Aakerblom, G.; Hagberg, N.; Mjoenes, L.; Heiberg, A.

2002-01-01

High indoor radon concentrations in buildings used for water treatment are not uncommon. When raw water is processed in an open system radon escapes from the water to the indoor air of the premises. It is not unusual that the staff of the waterworks have their offices in the building where the water is processed. If large volumes of water are processed and the evaporated radon can reach the workplaces the indoor radon concentration can be very high even if the radon concentration of the raw water is moderate. Groundwaters from aquifers in bedrock and soil and surface water that has been infiltrated through deposits of sand or gravel have the potential to cause high indoor radon levels. In surface water emanating directly from a lake or a river the radon concentrations are normally too low to cause problems. Three waterworks in central Sweden have been studied, Ludvika, Fredriksberg and Kolbaeck. The radon concentrations in the raw water of these waterworks are from 85 Bq/l to 300 Bq/l. Average indoor radon concentrations exceeding 17,000 Bq/m 3 have been measured in Ludvika with peaks of almost 37,000 Bq/m 3 . In Kolbaeck radon concentrations up to 56,000 Bq/m 3 have been measured. It is quite possible that employees of waterworks can receive doses exceeding 20 mSv per year (calculated according to ICRP:s dose conversion convention). Measurements of radon and gamma radiation from the waterworks are reported and methods to lower the indoor radon concentrations are discussed. (author)

Adaptive sensor-based ultra-high accuracy solar concentrator tracker

Science.gov (United States)

Brinkley, Jordyn; Hassanzadeh, Ali

2017-09-01

Conventional solar trackers use information of the sun's position, either by direct sensing or by GPS. Our method uses the shading of the receiver. This, coupled with nonimaging optics design allows us to achieve ultra-high concentration. Incorporating a sensor based shadow tracking method with a two stage concentration solar hybrid parabolic trough allows the system to maintain high concentration with acute accuracy.

Fabrication procedures for manufacturing high uranium concentration dispersion fuel elements

International Nuclear Information System (INIS)

Souza, Jose Antonio Batista de

2011-01-01

IPEN-CNEN/SP developed the technology to produce the dispersion type fuel elements for research reactors and made it available for routine production. Today, the fuel produced in IPEN-CNEN/SP is limited to the uranium concentration of 3.0 gU/cm 3 for U 3 Si 2 -Al dispersion-based and 2.3 gU/cm 3 for U 3 O 8 -Al dispersion. The increase of uranium concentration in fuel plates enables the reactivity of the reactor core reactivity to be higher and extends the fuel life. Concerning technology, it is possible to increase the uranium concentration in the fuel meat up to the limit of 4.8 gU/cm 3 in U 3 Si 2 -Al dispersion and 3.2 gU/cm 3 U 3 O 8 -Al dispersion. These dispersions are well qualified worldwide. This work aims to develop the manufacturing process of both fuel meats with high uranium concentrations, by redefining the manufacturing procedures currently adopted in the Nuclear Fuel Center of IPEN-CNEN/SP. Based on the results, it was concluded that to achieve the desired concentration, it is necessary to make some changes in the established procedures, such as in the particle size of the fuel powder and in the feeding process inside the matrix, before briquette pressing. These studies have also shown that the fuel plates, with a high concentration of U 3 Si 2 -Al, met the used specifications. On the other hand, the appearance of the microstructure obtained from U 3 O 8 -Al dispersion fuel plates with 3.2 gU/cm 3 showed to be unsatisfactory, due to the considerably significant porosity observed. The developed fabrication procedure was applied to U 3 Si 2 production at 4.8 gU/cm 3 , with enriched uranium. The produced plates were used to assemble the fuel element IEA-228, which was irradiated in order to check its performance in the IEA-R1 reactor at IPEN-CNEN/SP. These new fuels have potential to be used in the new Brazilian Multipurpose Reactor - RMB. (author)

Probabilistic Prognosis of Environmental Radioactivity Concentrations due to Radioisotopes Discharged to Water Bodies from Nuclear Power Plants.

Science.gov (United States)

Tomás Zerquera, Juan; Mora, Juan C; Robles, Beatriz

2017-11-15

Due to their very low values, the complexity of comparing the contribution of nuclear power plants (NPPs) to environmental radioactivity with modeled values is recognized. In order to compare probabilistic prognosis of radioactivity concentrations with environmental measurement values, an exercise was performed using public data of radioactive routine discharges from three representative Spanish nuclear power plants. Specifically, data on liquid discharges from three Spanish NPPs: Almaraz, Vandellós II, and Ascó to three different aquatic bodies (river, lake, and coast) were used. Results modelled using generic conservative models together with Monte Carlo techniques used for uncertainties propagation were compared with values of radioactivity concentrations in the environment measured in the surroundings of these NPPs. Probability distribution functions were inferred for the source term, used as an input to the model to estimate the radioactivity concentrations in the environment due to discharges to the water bodies. Radioactivity concentrations measured in bottom sediments were used in the exercise due to their accumulation properties. Of all the radioisotopes measured in the environmental monitoring programs around the NPPs, only Cs-137, Sr-90, and Co-60 had positive values greater than their respective detection limits. Of those, Sr-90 and Cs-137 are easily measured in the environment, but significant contribution from the radioactive fall-out due to nuclear explosions in the atmosphere exists, and therefore their values cannot be attributed to the NPPs. On the contrary, Co-60 is especially useful as an indicator of the radioactive discharges from NPPs because its presence in the environment can solely be attributed to the impact of the closer nuclear facilities. All the modelled values for Co-60 showed a reasonable correspondence with measured environmental data in all cases, being conservative in two of them. The more conservative predictions obtained with

Decadal and seasonal trends of nutrient concentration and export from highly managed coastal catchments.

Science.gov (United States)

Wan, Yongshan; Wan, Lei; Li, Yuncong; Doering, Peter

2017-05-15

Understanding anthropogenic and hydro-climatic influences on nutrient concentrations and export from highly managed catchments often necessitates trend detection using long-term monitoring data. This study analyzed the temporal trend (1979-2014) of total nitrogen (TN) and total phosphorus (TP) concentrations and export from four adjacent coastal basins in south Florida where land and water resources are highly managed through an intricate canal network. The method of integrated seasonal-trend decomposition using LOESS (LOcally weighted regrESSion) was employed for trend detection. The results indicated that long-term trends in TN and TP concentrations (increasing/decreasing) varied with basins and nutrient species, reflecting the influence of basin specific land and water management practices. These long-term trends were intervened by short-term highs driven by high rainfall and discharges and lows associated with regional droughts. Seasonal variations in TP were more apparent than for TN. Nutrient export exhibited a chemostatic behavior for TN from all the basins, largely due to the biogenic nature of organic N associated with the ubiquity of organic materials in the managed canal network. Varying degrees of chemodynamic export was present for TP, reflecting complex biogeochemical responses to the legacy of long-term fertilization, low soil P holding capacity, and intensive stormwater management. The anthropogenic and hydro-climatic influences on nutrient concentration and export behavior had great implications in nutrient loading abatement strategies for aquatic ecosystem restoration of the downstream receiving waterbody. Published by Elsevier Ltd.

Effect of high Xe-concentration in a plasma display panel with a SrCaO cold cathode

International Nuclear Information System (INIS)

Uchida, Giichiro; Kajiyama, Hiroshi; Shinoda, Tsutae; Uchida, Satoshi; Akiyama, Toshiyuki

2010-01-01

We present here measurements of high Xe-contents plasma display panel (PDP) with SrCaO cold cathode. Luminous efficacy (η) shows a two-step increase with Xe-concentration in Ne/Xe gas mixture: η drastically increases up to Xe-concentration of 30% (Xe: 30%), and then attains 5 lm/W at the highest Xe-concentration of Xe: 100%. The high performance PDP with Xe: 100% can be operated at low applied voltage between 230 and 377 V due to the high secondary electron emission from the SrCaO cathode. Emission measurements clearly show the change in discharge characteristics at Xe: 30%, where the discharge changes from a Ne/Xe mixture discharge to an almost pure Xe discharge, and the vacuum ultraviolet (VUV) radiation from the combination of resonance and excimer radiations to only excimer radiation. Theoretical analysis solving Boltzmann equation for electron demonstrates that increasing Xe-concentration enhances the collision frequency for electron impact excitation directly from ground state to lower levels concerned with the VUV radiation, resulting in a drastic increase in luminous efficacy up to Xe: 30%. Also, one-dimensional fluid simulation of a Ne/Xe dielectric barrier discharge clearly shows that a combination of high secondary electron emission cathode and high Xe-concentration is quite effective for high VUV radiation efficiency because it induces a drastic increase in electron-heating efficiency.

The ability of fungus Mucor racemosus Fresenius to degrade high concentration of detergent

Directory of Open Access Journals (Sweden)

Jakovljević Violeta D.

2014-01-01

Full Text Available The ability of fungus Mucor racemosus Fresenius to decompose high concentration of commercial detergent (MERIX, Henkel, Serbia was investigated in this study. Fungus was cultivated in liquid growth medium by Czapek with addition of detergent at concentration 0.5% during 16 days. The biochemical changes of pH, redox potential, amount of free and total organic acids, and activity of alkaline phosphatase were evaluated by analysis of fermentation broth. Simultaneously, biodegradation percentage of anionic surfactant of tested detergent was confirmed by MBAS assay. At the same time, the influence of detergent on fungal growth and total dry weight biomass was determined. Detergent at concentration 0.5% influenced on decreasing of pH value and increasing of redox potential as well as increasing of free and total organic acids. Enzyme activity of alkaline phosphatase was reduced by detergent at concentration 0.5%. The fungus was decomposed about 62% of anionic surfactant during 16 day. Due to fungus was produced higher dry weight biomass (53% in relation to control. [Projekat Ministarstva nauke Republike Srbije, br. III 43004

Origin of high ammonium, arsenic and boron concentrations in the proximity of a mine: Natural vs. anthropogenic processes.

Science.gov (United States)

Scheiber, Laura; Ayora, Carlos; Vázquez-Suñé, Enric; Cendón, Dioni I; Soler, Albert; Baquero, Juan Carlos

2016-01-15

human drinking; the second zone is downflow and contains groundwater suitable for continuous irrigation but not drinkable due to high ammonium concentrations; and the third zone contains groundwater of elevated salinity (up to 5940 μS cm(-1)) and is not useable due to high ammonium, arsenic and boron concentrations. Copyright © 2015 Elsevier B.V. All rights reserved.

High-performance flat-panel solar thermoelectric generators with high thermal concentration

Science.gov (United States)

Kraemer, Daniel; Poudel, Bed; Feng, Hsien-Ping; Caylor, J. Christopher; Yu, Bo; Yan, Xiao; Ma, Yi; Wang, Xiaowei; Wang, Dezhi; Muto, Andrew; McEnaney, Kenneth; Chiesa, Matteo; Ren, Zhifeng; Chen, Gang

2011-07-01

The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar thermal to electric power conversion technology based on the Seebeck effect and high thermal concentration, thus enabling wider applications. The developed solar thermoelectric generators (STEGs) achieved a peak efficiency of 4.6% under AM1.5G (1 kW m-2) conditions. The efficiency is 7-8 times higher than the previously reported best value for a flat-panel STEG, and is enabled by the use of high-performance nanostructured thermoelectric materials and spectrally-selective solar absorbers in an innovative design that exploits high thermal concentration in an evacuated environment. Our work opens up a promising new approach which has the potential to achieve cost-effective conversion of solar energy into electricity.

High-performance flat-panel solar thermoelectric generators with high thermal concentration.

Science.gov (United States)

Kraemer, Daniel; Poudel, Bed; Feng, Hsien-Ping; Caylor, J Christopher; Yu, Bo; Yan, Xiao; Ma, Yi; Wang, Xiaowei; Wang, Dezhi; Muto, Andrew; McEnaney, Kenneth; Chiesa, Matteo; Ren, Zhifeng; Chen, Gang

2011-05-01

The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar thermal to electric power conversion technology based on the Seebeck effect and high thermal concentration, thus enabling wider applications. The developed solar thermoelectric generators (STEGs) achieved a peak efficiency of 4.6% under AM1.5G (1 kW m(-2)) conditions. The efficiency is 7-8 times higher than the previously reported best value for a flat-panel STEG, and is enabled by the use of high-performance nanostructured thermoelectric materials and spectrally-selective solar absorbers in an innovative design that exploits high thermal concentration in an evacuated environment. Our work opens up a promising new approach which has the potential to achieve cost-effective conversion of solar energy into electricity. © 2011 Macmillan Publishers Limited. All rights reserved

Insulin Resistance Induced by a High Fructose Diet in Rats Due to Hepatic Disturbance

International Nuclear Information System (INIS)

Heibashy, M.I.A.; Mazen, G.M.A.; Kelada, N.A.H.

2013-01-01

High consumption of dietary fructose is accused of being responsible for the development of the insulin resistance (IR) syndrome. Concern has arisen because of the realization that fructose, at elevated concentrations, can promote metabolic changes that are potentially deleterious. Among these changes is IR which manifests as a decreased biological response to normal levels of plasma insulin. Therefore, this experiment was designed to evaluate the role of high fructose diet on metabolic syndrome in rats. The experimental animals were divided into two batches. The control batch received a control diet; the second batch was given a high-fructose diet as the sole source of carbohydrate. The rats were continued on the dietary regimen for 1, 2 and 3 months. After the experimental periods, fructose fed rats groups showed significant elevations in the levels of glucose, insulin sensitivity, liver function tests, nitric oxide and tumor necrosis factor-α when compared to their corresponding values in the rats fed normal diet. Moreover, liver lipid peroxidation [thiobarbituric acid-reactive substance (TBARS) and lipid hydroperoxide concentrations were remarkably increased in high-fructose-fed rats according to the time of administration (1, 2 and 3 months). On the other hand, the activities of enzymatic antioxidants (glutathione reductase and glutathione peroxidase) and glyoxalase I and II were significantly declined in this group. In conclusion, high fructose feeding raises liver dysfunction and causes the features of metabolic syndrome (insulin resistance) in rats dependent on the time of administration due to different mechanisms which were discussed in this work according to available recent researches

High nutrient concentration and temperature alleviated formation of large colonies of Microcystis: Evidence from field investigations and laboratory experiments.

Science.gov (United States)

Zhu, Wei; Zhou, Xiaohua; Chen, Huaimin; Gao, Li; Xiao, Man; Li, Ming

2016-09-15

Correlations between Microcystis colony size and environmental factors were investigated in Meiliang Bay and Gonghu Bay of Lake Taihu (China) from 2011 to 2013. Compared with Gonghu Bay, both nutrient concentrations and Microcystis colony sizes were greater in Meiliang Bay. The median colony size (D50: 50% of the total mass of particles smaller than this size) increased from April to August and then decreased until November. In both bays, the average D50 of Microcystis colonies were 500 μm) dominated in summer. The differences in colony size in Meiliang Bay and Gonghu Bay were probably due to horizontal drift driven by the prevailing south wind in summer. Redundancy analysis (RDA) of field data indicated that colony size was negatively related to nutrient concentrations but positively related to air temperature, suggesting that low nutrient concentrations and high air temperature promoted formation of large colonies. To validate the field survey, Microcystis colonies collected from Lake Taihu were cultured at different temperatures (15, 20, 25 and 30 °C) under high and low nutrient concentrations for 9 days. The size of Microcystis colonies significantly decreased when temperature was above 20 °C but had no significant change at 15 °C. The differences in temperature effects on colony formation shown from field and laboratory suggested that the larger colonies in summer were probably due to the longer growth period rather than the higher air temperature and light intensity. In addition, colony size decreased more significantly at high nutrient levels. Therefore, it could be concluded that high nutrient concentration and temperature may alleviate formation of large colonies of Microcystis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Is a high serum copper concentration a risk factor for implantation failure?

Science.gov (United States)

Matsubayashi, Hidehiko; Kitaya, Kotaro; Yamaguchi, Kohei; Nishiyama, Rie; Takaya, Yukiko; Ishikawa, Tomomoto

2017-08-10

Copper-containing contraceptive devices may deposit copper ions in the endometrium, resulting in implantation failure. The deposition of copper ions in many organs has been reported in patients with untreated Wilson's disease. Since these patients sometimes exhibit subfertility and/or early pregnancy loss, copper ions were also considered to accumulate in the uterine endometrium. Wilson's disease patients treated with zinc successfully delivered babies because zinc interfered with the absorption of copper from the gastrointestinal tract. These findings led to the hypothesis that infertile patients with high serum copper concentrations may have implantation failure due to the excess accumulation of copper ions. The relationship between implantation (pregnancy) rates and serum copper concentrations has not yet been examined. The Japanese government recently stated that actual copper intake was higher among Japanese than needed. Therefore, the aim of the present study was to investigate whether serum copper concentrations are related to the implantation (pregnancy) rates of human embryos in vivo. We included 269 patients (age copper, and zinc concentrations were measured 16 days after the first date of progesterone replacement. We compared 96 women who were pregnant without miscarriage at 10 weeks of gestation (group P) and 173 women who were not pregnant (group NP). No significant differences were observed in age or BMI between the groups. Copper concentrations were significantly higher in group NP (average 193.2 μg/dL) than in group P (average 178.1 μg/dL). According to the area under the curve (AUC) on the receiver operating characteristic curve for the prediction of clinical pregnancy rates, the Cu/Zn ratio (AUC 0.64, 95% CI 0.54-0.71) was a better predictor than copper or zinc. When we set the cut-off as 1.59/1.60 for the Cu/Zn ratio, sensitivity, specificity, the positive predictive value, and negative predictive value were 0.98, 0.29, 0.71, and 0

Applications of nonimaging optics for very high solar concentrations

International Nuclear Information System (INIS)

O'Gallagher, J.; Winston, R.

1997-01-01

Using the principles and techniques of nonimaging optics, solar concentrations that approach the theoretical maximum can be achieved. This has applications in solar energy collection wherever concentration is desired. In this paper, we survey recent progress in attaining and using high and ultrahigh solar fluxes. We review a number of potential applications for highly concentrated solar energy and the current status of the associated technology. By making possible new and unique applications for intense solar flux, these techniques have opened a whole new frontier for research and development of potentially economic uses of solar energy

Origin of high ammonium, arsenic and boron concentrations in the proximity of a mine: Natural vs. anthropogenic processes

International Nuclear Information System (INIS)

Scheiber, Laura; Ayora, Carlos; Vázquez-Suñé, Enric; Cendón, Dioni I.; Soler, Albert; Baquero, Juan Carlos

2016-01-01

for human drinking; the second zone is downflow and contains groundwater suitable for continuous irrigation but not drinkable due to high ammonium concentrations; and the third zone contains groundwater of elevated salinity (up to 5940 μS cm"−"1) and is not useable due to high ammonium, arsenic and boron concentrations. - Highlights: • Differentiation between natural and anthropogenic sources of NH_4, As and B • Assessment of hydrogeochemical processes that control the presence of NH_4, As and B in groundwater • High NH_4, As and B concentrations in Niebla-Posadas aquifer • Contribution to scientific-based aquifer management • Aquifer zonation based on groundwater quality for its good management

Origin of high ammonium, arsenic and boron concentrations in the proximity of a mine: Natural vs. anthropogenic processes

Energy Technology Data Exchange (ETDEWEB)

Scheiber, Laura, E-mail: scheiber.ls@gmail.com [Institute of Environmental Assessment and Water Research, CSIC, Jordi Girona 18. E-08034 Barcelona (Spain); Ayora, Carlos; Vázquez-Suñé, Enric [Institute of Environmental Assessment and Water Research, CSIC, Jordi Girona 18. E-08034 Barcelona (Spain); Cendón, Dioni I. [Australian Nuclear Science and Technology Organisation, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); School of Biological, Earth and Environmental Sciences (BEES), University of New South Wales (UNSW), NSW 2052 (Australia); Soler, Albert [Departament de Cristallografia, Mineralogia i Dipòsits Minerals, Facultat de Geologia, Universitat de Barcelona, C/Martí Franquès, sn., Barcelona (Spain); Baquero, Juan Carlos [Cobre Las Cruces S.A., Carretera SE-3410 km 4, 41860 Gerena, Sevilla (Spain)

2016-01-15

of sufficient quality for human drinking; the second zone is downflow and contains groundwater suitable for continuous irrigation but not drinkable due to high ammonium concentrations; and the third zone contains groundwater of elevated salinity (up to 5940 μS cm{sup −1}) and is not useable due to high ammonium, arsenic and boron concentrations. - Highlights: • Differentiation between natural and anthropogenic sources of NH{sub 4}, As and B • Assessment of hydrogeochemical processes that control the presence of NH{sub 4}, As and B in groundwater • High NH{sub 4}, As and B concentrations in Niebla-Posadas aquifer • Contribution to scientific-based aquifer management • Aquifer zonation based on groundwater quality for its good management.

Rheological behavior of high-concentration sodium caseinate dispersions.

Science.gov (United States)

Loveday, Simon M; Rao, M Anandha; Creamer, Lawrence K; Singh, Harjinder

2010-03-01

Apparent viscosity and frequency sweep (G', G'') data for sodium caseinate dispersions with concentrations of approximately 18% to 40% w/w were obtained at 20 degrees C; colloidal glass behavior was exhibited by dispersions with concentration >or=23% w/w. The high concentrations were obtained by mixing frozen powdered buffer with sodium caseinate in boiling liquid nitrogen, and allowing the mixtures to thaw and hydrate at 4 degrees C. The low-temperature G'-G'' crossover seen in temperature scans between 60 and 5 degrees C was thought to indicate gelation. Temperature scans from 5 to 90 degrees C revealed gradual decrease in G' followed by plateau values. In contrast, G'' decreased gradually and did not reach plateau values. Increase in hydrophobicity of the sodium caseinate or a decrease in the effective volume fraction of its aggregates may have contributed to these phenomena. The gelation and end of softening temperatures of the dispersions increased with the concentration of sodium caseinate. From an Eldridge-Ferry plot, the enthalpy of softening was estimated to be 29.6 kJ mol(-1). The results of this study should be useful for creating new products with high concentrations of sodium caseinate.

Extreme concentration fluctuations due to local reversibility of mixing in turbulent flows

Science.gov (United States)

Xia, Hua; Francois, Nicolas; Punzmann, Horst; Szewc, Kamil; Shats, Michael

2018-05-01

Mixing of a passive scalar in a fluid (e.g. a radioactive spill in the ocean) is the irreversible process towards homogeneous distribution of a substance. In a moving fluid, due to the chaotic advection [H. Aref, J. Fluid Mech. 143 (1984) 1; J. M. Ottino, The Kinematics of Mixing: Stretching,Chaos and Transport (Cambridge University Press, Cambridge, 1989)] mixing is much faster than if driven by molecular diffusion only. Turbulence is known as the most efficient mixing flow [B. I. Shraiman and E. D. Siggia, Nature 405 (2000) 639]. We show that in contrast to spatially periodic flows, two-dimensional turbulence exhibits local reversibility in mixing, which leads to the generation of unpredictable strong fluctuations in the scalar concentration. These fluctuations can also be detected from the analysis of the fluid particle trajectories of the underlying flow.

Fluidized bed combustion of single coal char particles at high CO{sub 2} concentration

Energy Technology Data Exchange (ETDEWEB)

Scala, F.; Chirone, R. [CNR, Naples (Italy)

2010-12-15

Combustion of single coal char particles was studied at 850{sup o}C in a lab-scale fluidized bed at high CO{sub 2} concentration, typical of oxyfiring conditions. The burning rate of the particles was followed as a function of time by continuously measuring the outlet CO and O{sub 2} concentrations. Some preliminary evaluations on the significance of homogeneous CO oxidation in the reactor and of carbon gasification by CO{sub 2} in the char were also carried out. Results showed that the carbon burning rate increases with oxygen concentration and char particle size. The particle temperature is approximately equal to that of the bed up to an oxygen concentration of 2%, but it is considerably higher for larger oxygen concentrations. Both CO{sub 2} gasification of char and homogeneous CO oxidation are not negligible. The gasification reaction rate is slow and it is likely to be controlled by intrinsic kinetics. During purely gasification conditions the extent of carbon loss due to particle attrition by abrasion (estimated from the carbon mass balance) appears to be much more important than under combustion conditions.

Compact high-sensitivity potentiometer for detection of low ion concentrations in liquids

Science.gov (United States)

Balevicius, Z.; Lescinskas, R.; Celiesiute, R.; Stirke, A.; Balevicius, S.; Kersulis, S.; Bleizgys, V.; Maciuleviciene, R.; Ramanavicius, A.; Zurauskiene, N.

2018-04-01

The compact potentiometer, based on an electronic circuit protected from electrostatic and electromagnetic interference, was developed for the measurement of low ion concentrations in liquids. The electronic circuit of the potentiometer, consisting of analogous and digital parts, enables the measurement of fA currents. This makes it possible to perform reliable measurements of ion concentrations in liquids that are as small as 10-8-10-7M. The instrument was tested using electrodes that were selective for tetraphenylphosphonium (TPP+) ions. It was demonstrated that the characteristic response time of the potentiometer electronic circuit to changes in the concentration of these ions in a liquid was in the order of 10 s. An investigation of TPP+ absorption by baker yeast has shown that this device can be successfully used for long term (several hours) measurements with zero signal drift, which was about 1 μV/s. Finally, due to the small dimensions of the electronic circuit (7.5 × 2 × 1.5 cm), this potentiometer can be easily installed at a large apparatus in the laboratory condition (≈25 °C), such as high pulsed electrical generators of magnetic fields that are used in electroporation studies of biological cells.

Denitrification of fertilizer wastewater at high chloride concentration

DEFF Research Database (Denmark)

Ucisik, Ahmed Süheyl; Henze, Mogens

Wastewater from fertilizer industry is characterized by high contents of chloride concentration, which normally vary between 60 and 76 g/l. Experiments with bilogical denitrification were performed in lab-scale "fill and draw" reactors with synthetic wastewater with chloride concentrations up to 77.......4 g/l. The results of the experiments showed that biological denitrification was feasible at the extreme environmental conditions prevailing in fertilizer wastewater. Stable continuous biological denitrfication of the synthetic high chloride wastewater was performed up to 77.4 g Cl/l at 37 degree C...

Highly concentrating Fresnel lenses

International Nuclear Information System (INIS)

Kritchman, E.M.; Friesem, A.A.; Yekutieli, G.

1979-01-01

A new type of concave Fresnel lens capable of concentrating solar radiation very near the ultimate concentration limit is considered. The differential equations that describe the lens are solved to provide computed solutions which are then checked by ray tracing techniques. The performance (efficiency and concentration) of the lens is investigated and compared to that of a flat Fresnel lens, showing that the new lens is preferable for concentrating solar radiation. (author)

Butanol production from concentrated lactose/whey permeate: Use of pervaporation membrane to recover and concentrate product

Science.gov (United States)

In these studies butanol (acetone butanol ethanol, or ABE) was produced from concentrated lactose/whey permeate containing 211 gL-1 lactose. Fermentation of such a highly concentrated lactose solution was possible due to simultaneous product removal using a pervaporation membrane. In this system a p...

Ultra flat ideal concentrators of high concentration

Energy Technology Data Exchange (ETDEWEB)

Chaves, Julio [IST, Physics Dept., Lisboa (Portugal); INETI-DER, Lisboa (Portugal); Collares-Pereira, Manuel [INETI-DER, Lisboa (Portugal)

2000-07-01

A new method for the design of nonimaging devices is presented. Its application to the design of ultra flat compact concentrators is analysed. These new concentrators are based on a combination of two stages: the first one is composed of a large number of small structures placed side by side and the second one is a very compact single device concentrating the radiation to the limit. These devices are ideal for 2D. These compact designs are much more compact than the traditional ones like lens-mirror combinations or parabolic primaries with nonimaging secondaries. Besides, they can be designed for any acceptance angle, while the traditional ones are limited to small acceptance angles. (Author)

Tailoring Microbial Electrochemical Cells for Production of Hydrogen Peroxide at High Concentrations and Efficiencies.

Science.gov (United States)

Young, Michelle N; Links, Mikaela J; Popat, Sudeep C; Rittmann, Bruce E; Torres, César I

2016-12-08

A microbial peroxide producing cell (MPPC) for H 2 O 2 production at the cathode was systematically optimized with minimal energy input. First, the stability of H 2 O 2 was evaluated using different catholytes, membranes, and catalyst materials. On the basis of these results, a flat-plate MPPC fed continuously using 200 mm NaCl catholyte at a 4 h hydraulic retention time was designed and operated, producing H 2 O 2 for 18 days. H 2 O 2 concentration of 3.1 g L -1 H 2 O 2 with 1.1 Wh g -1 H 2 O 2 power input was achieved in the MPPC. The high H 2 O 2 concentration was a result of the optimum materials selected. The small energy input was largely the result of the 0.5 cm distance between the anode and cathode, which reduced ionic transport losses. However, >50 % of operational overpotentials were due to the 4.5-5 pH unit difference between the anode and cathode chambers. The results demonstrate that a MPPC can continuously produce H 2 O 2 at high concentration by selecting compatible materials and appropriate operating conditions. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Hole traps associated with high-concentration residual carriers in p-type GaAsN grown by chemical beam epitaxy

Energy Technology Data Exchange (ETDEWEB)

Elleuch, Omar, E-mail: mr.omar.elleuch@gmail.com; Wang, Li; Lee, Kan-Hua; Demizu, Koshiro; Ikeda, Kazuma; Kojima, Nobuaki; Ohshita, Yoshio; Yamaguchi, Masafumi [Toyota Technological Institute, 2-12-1 Hisakata, Tempaku, Nagoya 468-8511 (Japan)

2015-01-28

The hole traps associated with high background doping in p-type GaAsN grown by chemical beam epitaxy are studied based on the changes of carrier concentration, junction capacitance, and hole traps properties due to the annealing. The carrier concentration was increased dramatically with annealing time, based on capacitance–voltage (C–V) measurement. In addition, the temperature dependence of the junction capacitance (C–T) was increased rapidly two times. Such behavior is explained by the thermal ionization of two acceptor states. These acceptors are the main cause of high background doping in the film, since the estimated carrier concentration from C–T results explains the measured carrier concentration at room temperature using C–V method. The acceptor states became shallower after annealing, and hence their structures are thermally unstable. Deep level transient spectroscopy (DLTS) showed that the HC2 hole trap was composed of two signals, labeled HC21 and HC22. These defects correspond to the acceptor levels, as their energy levels obtained from DLTS are similar to those deduced from C–T. The capture cross sections of HC21 and HC22 are larger than those of single acceptors. In addition, their energy levels and capture cross sections change in the same way due to the annealing. This tendency suggests that HC21 and HC22 signals originate from the same defect which acts as a double acceptor.

Hole traps associated with high-concentration residual carriers in p-type GaAsN grown by chemical beam epitaxy

International Nuclear Information System (INIS)

Elleuch, Omar; Wang, Li; Lee, Kan-Hua; Demizu, Koshiro; Ikeda, Kazuma; Kojima, Nobuaki; Ohshita, Yoshio; Yamaguchi, Masafumi

2015-01-01

The hole traps associated with high background doping in p-type GaAsN grown by chemical beam epitaxy are studied based on the changes of carrier concentration, junction capacitance, and hole traps properties due to the annealing. The carrier concentration was increased dramatically with annealing time, based on capacitance–voltage (C–V) measurement. In addition, the temperature dependence of the junction capacitance (C–T) was increased rapidly two times. Such behavior is explained by the thermal ionization of two acceptor states. These acceptors are the main cause of high background doping in the film, since the estimated carrier concentration from C–T results explains the measured carrier concentration at room temperature using C–V method. The acceptor states became shallower after annealing, and hence their structures are thermally unstable. Deep level transient spectroscopy (DLTS) showed that the HC2 hole trap was composed of two signals, labeled HC21 and HC22. These defects correspond to the acceptor levels, as their energy levels obtained from DLTS are similar to those deduced from C–T. The capture cross sections of HC21 and HC22 are larger than those of single acceptors. In addition, their energy levels and capture cross sections change in the same way due to the annealing. This tendency suggests that HC21 and HC22 signals originate from the same defect which acts as a double acceptor

Dramatic effect on Selenium concentration in blood serum due to the difference between the Hungarian and Indian dietary habits

International Nuclear Information System (INIS)

Szuecs, Z.; Lahiri, S.; Andrasi, D.; Kovacs, B.

2012-01-01

Complete text of publication follows. The importance of Selenium as trace element in animals, as well as in humans is well known. The deficiency of Selenium was observed in case of several heavy or fatal clinical events such as high infant mortality, premature, malformations and even prostate cancer. Hungary is in the top of their worldwide statistic with parallel of the low concentration of Selenium in soil as well as in food. The direct correlation can explain in Venezuela, where the prostate cancer is 'unknown disease'. The concentration of Selenium in India is higher than the worldwide level. Under the scientific bilateral cooperation 'Speciation dependent studies on physicochemical behavior of some elements in trace scale in natural and synthetic system' the Selenium was determined in human blood serum from the group of Hungarian and group of Indian patients. The samples were given in same time from each group. The main goal of the study was explain the effect of the traditional dietary habit for the level of Selenium. Therefore the samples were taken from the visiting scientist just arrived to the host institute as well as from the host scientists too. After 2 weeks stay the sampling was repeated, when the guest scientists eat the same food as the host scientists. The measurements were done in Thermo-2 ICP-MS from blood-serum separated by centrifuge. The results are summarized in Table 1. Dramatic effect was found for the level of Selenium in blood serum. As it was expected the Hungarian samples showed low concentration of Selenium in starting of the visit, as well as the high concentration was found in Indian sample, comparing to the Hungarian sample. After two weeks the Hungarian sample showed much higher concentration, however it was still less, than in Indian sample. Similar effect was found during the visit the Indian scientists in Hungary, however their Selenium concentration decreased not so spectacular due to the Selenium 'store' in body. The general

Estimates concentrations in bottled 222Rn of the dose due to mineral waters in Iran

International Nuclear Information System (INIS)

Assadi, M. R.; Esmaealnejad, M.; Rahmatinejad, Z.

2006-01-01

Radon is a radionuclide that has the main role in exposure. Radon in water causes exposure in whole body but the largest dose being received by the stomach, as EPA (Environmental Protection Agency) estimates that radon in drinking water causes about 168 cancer deaths per year: 89 p ercent f rom lung cancer caused by breathing released to the indoor air from water and 11 p ercent f rom stomach cancer caused by consuming water containing radon. Now days the consumption of bottled mineral waters has become very popular. As is known, some kinds of mineral waters contain naturally occurring radionuclides in higher concentration than the usual drinking (tap) water. Surveys and reports on radon in most surface waters is low compared with radon level in groundwater and mineral water. In our work, the concentration of Rn(222) was determined in some bottled mineral waters available in Iran , and in next step the dose contribution ; due to ingestion ; for 1 l d -1 bottled mineral water consumption.

Atmospheric conditions during high ragweed pollen concentrations in Zagreb, Croatia

Science.gov (United States)

Prtenjak, Maja Telišman; Srnec, Lidija; Peternel, Renata; Madžarević, Valentina; Hrga, Ivana; Stjepanović, Barbara

2012-11-01

We examined the atmospheric conditions favourable to the occurrence of maximum concentrations of ragweed pollen with an extremely high risk of producing allergy. Over the 2002-2009 period, daily pollen data collected in Zagreb were used to identify two periods of high pollen concentration (> 600 grains/m3) for our analysis: period A (3-4 September 2002) and period B (6-7 September 2003). Synoptic conditions in both periods were very similar: Croatia was under the influence of a lower sector high pressure system moving slowly eastward over Eastern Europe. During the 2002-2009 period, this type of weather pattern (on ~ 70% of days), in conjunction with almost non-gradient surface pressure conditions in the area (on ~ 30% of days) characterised days when the daily pollen concentrations were higher than 400 grains/m3. Numerical experiments using a mesoscale model at fine resolution showed successful multi-day simulations reproducing the local topographic influence on wind flow and in reasonable agreement with available observations. According to the model, the relatively weak synoptic flow (predominantly from the eastern direction) allowed local thermal circulations to develop over Zagreb during both high pollen episodes. Two-hour pollen concentrations and 48-h back-trajectories indicated that regional-range transport of pollen grains from the central Pannonian Plain was the cause of the high pollen concentrations during period A. During period B, the north-westward regional-range transport in Zagreb was supplemented significantly by pronounced horizontal recirculation of pollen grains. This recirculation happened within the diurnal local circulation over the city, causing a late-evening increase in pollen concentration.

Efficacy of high iodine concentration contrast medium with saline pushing in hepatic CT in patients with chronic liver disease. Comparison of high doses-standard contrast medium concentration

International Nuclear Information System (INIS)

Matoba, Munetaka; Kondo, Tamaki; Nishikawa, Takahiro; Kuginuki, Yasuaki; Yokota, Hajime; Higashi, Kotaro; Tonami, Hisao

2006-01-01

The aim of this study was to compare the enhancement of liver parenchyama with high iodine concentration contrast medium with saline pushing to that with high doses standard iodine concentration in hepatic CT in patients with chronic liver disease. There was no statistically significant difference regarding to the enhancement of liver parenchyama between the 370 mgI/ml of contrast medium with saline pushing and high doses standard iodine concentration contrast medium. (author)

Study on high concentration solar concentrator using a Fresnel lens with a secondary concentrator; Fresnel lens to niji shukokei wo mochiita solar chemistry yo kobairitsu shukokei ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Aihara, T; Suzuki, A; Fujibayashi, K [Tokyo University of Agriculture and Technology, Tokyo (Japan)

1997-11-25

A high concentration light collection system for solar chemistry was devised by using an inexpensive Fresnel lens in a primary concentration system and a conical type concentrator in a secondary concentration system. A Fresnel lens alone would not achieve sufficiently high light collecting magnification to attain high temperatures because of restrictions in the opening angle as seen from a focus. Therefore, a secondary concentration system was installed on a focus for an attempt of stopping. Reflection plane of a three-dimensional compound parabolic concentrator (CPC) is a rotary parabolic plane, whose process is expensive because of its surface processing accuracy. Therefore, a conical type concentrator was employed as a secondary concentration system. This system may not be capable of achieving as high concentration as in the CPC, but its shape is simple and it is inexpensive. In its optimization, a complete black body surface placed in vacuum atmosphere was hypothesized as a light concentrating part for the secondary concentration system to calculate heat collecting efficiencies at respective temperature settings. Using simultaneously the secondary concentration system, rather than collecting heat by using a Fresnel lens alone, has attained as high value as from 5.99% (500 degC) to 43.47% (1400 degC). Economical high-temperature heat collection of solar chemistry level may be possible by using a Fresnel lens and a conical secondary concentration system. 1 ref., 7 figs., 2 tabs.

Near-bed observations of high-concentration sediment transport in the Changjiang Estuary

Science.gov (United States)

Zhou, Z.; Ge, J.; Ding, P.

2017-12-01

The North Passage, the core of turbidity maximum in the Changjiang Estuary, is now under the strong sedimentation due to the abundant sediment supply from the upstream Changjiang River and the river-tide interacted dynamics. Recent studies suggested that strong siltation could be attributed to bottom high-concentration sediment transport, which however is very difficult to be detected and observed by vessel-anchored survey methods. To better understand the mechanisms of sediment transport and deposition in the channel region of the North Passage and its adjacent areas, we conducted continuous field observations which covered spring and neap tide period in the wintertime of 2016, the summertime of 2015 and 2017, focusing on near-bottom sediment transport. Tripods mounted with multiple instruments, including up-looking and down-looking Acoustic Doppler Current Profilers(ADCP), Vector Current Meter(ADV), Optical Backscatter Sensor(OBS), ASM, ALEC and RBR were used to observe the near-bottom physical process and its induced sediment dynamics. Results of these observations clearly described the current-wave-sediment interaction, which produced different patterns of bottom mud suspension at different tripods. Both hydrodynamic features and suspended sediment showed variations between spring and neap tide. Taking data of 2016 as an example, averaged suspended sediment concentration(SSC) at two tripods was 1.52 g/L and 2.13 g/L during the neap tide, 4.51 g/L and 5.75 g/L with the peak value reaching 25 g/L during the spring tide. At the tripod which was closer to the channel region, three peaks of SSC during the spring tide occurred near the flood slack with notable salinity increase, indicating the impact of saltwater intrusion on the bottom hydrodynamics. The results showed the occurrence of high-concentration suspended sediment was probably related to combined effects of bottom salinity intrusion, turbulent kinetic energy(TKE) and local stratification due to density

High concentration suspended sediment measurments using acontinuous fiber optic in-stream transmissometer

Energy Technology Data Exchange (ETDEWEB)

Campbell, Chris G.; Laycak, Danny T.; Hoppes, William; Tran,Nguyen T.; Shi, Frank G.

2004-05-26

Suspended sediment loads mobilized during high flow periods in rivers and streams are largely uncharacterized. In smaller and intermittent streams, a large storm may transport a majority of the annual sediment budget. Therefore monitoring techniques that can measure high suspended sediment concentrations at semi-continuous time intervals are needed. A Fiber optic In-stream Transmissometer (FIT) is presented for continuous measurement of high concentration suspended sediment in storm runoff. FIT performance and precision were demonstrated to be reasonably good for suspended sediment concentrations up to 10g/L. The FIT was compared to two commercially available turbidity devices and provided better precision and accuracy at both high and low concentrations. Both turbidity devices were unable to collect measurements at concentrations greater than 4 g/L. The FIT and turbidity measurements were sensitive to sediment particle size. Particle size dependence of transmittance and turbidity measurement poses the greatest problem for calibration to suspended sediment concentration. While the FIT was demonstrated to provide acceptable measurements of high suspended sediment concentrations, approaches to real-time suspended sediment detection need to address the particle size dependence in concentration measurements.

High concentrations of thiosulfate in scala tympani perilymph after systemic administration in the guinea pig.

Science.gov (United States)

Pierre, Pernilla Videhult; Engmér, Cecilia; Wallin, Inger; Laurell, Göran; Ehrsson, Hans

2009-02-01

High concentrations of the antioxidant thiosulfate reach scala tympani perilymph after i.v. administration in the guinea pig. Thiosulfate concentrations in perilymph remain elevated longer than in blood. This warrants further studies on the possibility of obtaining otoprotection by thiosulfate administration several hours before that of cisplatin without compromising the anticancer effect caused by cisplatin inactivation in the blood compartment. Thiosulfate may reduce cisplatin-induced ototoxicity, presumably by oxidative stress relief and formation of inactivate platinum complexes. This study aimed to explore to what extent thiosulfate reaches scala tympani perilymph after systemic administration in the guinea pig. Scala tympani perilymph (1 microl) was aspirated from the basal turn of each cochlea up to 3 h after thiosulfate administration (103 mg/kg b.w., i.v.). Blood samples were also taken. Thiosulfate was quantified by HPLC and fluorescence detection. Substantial thiosulfate concentrations were found in perilymph. The area under the concentration-time curve for thiosulfate in perilymph and blood was 3100 microMxmin and 6300 microMxmin, respectively. The highest thiosulfate concentrations in perilymph were found at the first sampling at about 10 min. Due to a more rapid elimination from blood, perilymph concentrations exceeded those of blood towards the end of the experiment.

Cellulase Inhibition by High Concentrations of Monosaccharides

DEFF Research Database (Denmark)

Hsieh, Chia-Wen; Cannella, David; Jørgensen, Henning

2014-01-01

Biological degradation of biomass on an industrial scale culminates in high concentrations of end products. It is known that the accumulation of glucose and cellobiose, end products of hydrolysis, inhibit cellulases and decrease glucose yields. Aside from these end products, however, other monosa...

Multiphysics modelling and experimental validation of high concentration photovoltaic modules

International Nuclear Information System (INIS)

Theristis, Marios; Fernández, Eduardo F.; Sumner, Mike; O'Donovan, Tadhg S.

2017-01-01

Highlights: • A multiphysics modelling approach for concentrating photovoltaics was developed. • An experimental campaign was conducted to validate the models. • The experimental results were in good agreement with the models. • The multiphysics modelling allows the concentrator’s optimisation. - Abstract: High concentration photovoltaics, equipped with high efficiency multijunction solar cells, have great potential in achieving cost-effective and clean electricity generation at utility scale. Such systems are more complex compared to conventional photovoltaics because of the multiphysics effect that is present. Modelling the power output of such systems is therefore crucial for their further market penetration. Following this line, a multiphysics modelling procedure for high concentration photovoltaics is presented in this work. It combines an open source spectral model, a single diode electrical model and a three-dimensional finite element thermal model. In order to validate the models and the multiphysics modelling procedure against actual data, an outdoor experimental campaign was conducted in Albuquerque, New Mexico using a high concentration photovoltaic monomodule that is thoroughly described in terms of its geometry and materials. The experimental results were in good agreement (within 2.7%) with the predicted maximum power point. This multiphysics approach is relatively more complex when compared to empirical models, but besides the overall performance prediction it can also provide better understanding of the physics involved in the conversion of solar irradiance into electricity. It can therefore be used for the design and optimisation of high concentration photovoltaic modules.

Polonium-210 concentration of cigarettes traded in Cuba and their estimated dose contribution due to smoking

International Nuclear Information System (INIS)

Brigido Flores, O.; Montalvan Estrada, A.; Fabelo Bonet, O.; Barreras Caballero, A.

2015-01-01

Cigarette smoking is one of the pathways that might contribute significantly to the increase in the radiation dose reaching man, due to the relatively large concentrations of polonium-210 found in tobacco leaves. The results of 200 Po determination on the 11 most frequently smoked brands of cigarettes and cigars which constitute over 75% of the total cigarette consumption in Cuba are presented and discussed. Moreover, the polonium content in cigarette smoke was estimated on the basis of its activity in cigarettes, ash, fresh filters and post-smoking filters. 210 Po was determined by gas flow proportional detector after spontaneous deposition of 210 Po on a high copper-content disk. The annual committed equivalent dose for lungs and the annual effective dose for smokers between 12-17 years old and for adults were calculated on the basis of the 210 Po inhalation through cigarette smoke. The results showed concentration ranging from 9.3 to 14.4 mBq per cigarette with a mean value of 11.8 ± 0.6 mBq.Cig -1 . the results of this work indicate that Cuban smokers who smoke one pack (20 cigarettes) per day inhale from 62 to 98 mBq.d -1 of 210 Po and smokers between 12-17 years old who consume 10 cigarettes daily inhale from 30-50 mBq.d -1 . The average committed equivalent dose for lungs is estimated to be 466 ± 36 and 780 ± 60 μSv.year -1 for young and adult smokers, respectively and annual committed effective dose is calculated to be 60 ± 5 and 100 ± 8 μSv for these two groups of smokers, respectively. (Author)

Differences in Swallowing between High and Low Concentration Taste Stimuli

Directory of Open Access Journals (Sweden)

Ahmed Nagy

2014-01-01

Full Text Available Taste is a property that is thought to potentially modulate swallowing behavior. Whether such effects depend on taste, intensity remains unclear. This study explored differences in the amplitudes of tongue-palate pressures in swallowing as a function of taste stimulus concentration. Tongue-palate pressures were collected in 80 healthy women, in two age groups (under 40, over 60, stratified by genetic taste status (nontasters, supertasters. Liquids with different taste qualities (sweet, sour, salty, and bitter were presented in high and low concentrations. General labeled magnitude scale ratings captured perceived taste intensity and liking/disliking of the test liquids. Path analysis explored whether factors of taste, concentration, age group, and/or genetic taste status impacted: (1 perceived intensity; (2 palatability; and (3 swallowing pressures. Higher ratings of perceived intensity were found in supertasters and with higher concentrations, which were more liked/disliked than lower concentrations. Sweet stimuli were more palatable than sour, salty, or bitter stimuli. Higher concentrations elicited stronger tongue-palate pressures independently and in association with intensity ratings. The perceived intensity of a taste stimulus varies as a function of stimulus concentration, taste quality, participant age, and genetic taste status and influences swallowing pressure amplitudes. High-concentration salty and sour stimuli elicit the greatest tongue-palate pressures.

High pressure inertial focusing for separating and concentrating bacteria at high throughput

Science.gov (United States)

Cruz, J.; Hooshmand Zadeh, S.; Graells, T.; Andersson, M.; Malmström, J.; Wu, Z. G.; Hjort, K.

2017-08-01

Inertial focusing is a promising microfluidic technology for concentration and separation of particles by size. However, there is a strong correlation of increased pressure with decreased particle size. Theory and experimental results for larger particles were used to scale down the phenomenon and find the conditions that focus 1 µm particles. High pressure experiments in robust glass chips were used to demonstrate the alignment. We show how the technique works for 1 µm spherical polystyrene particles and for Escherichia coli, not being harmful for the bacteria at 50 µl min-1. The potential to focus bacteria, simplicity of use and high throughput make this technology interesting for healthcare applications, where concentration and purification of a sample may be required as an initial step.

[Condition optimization for bio-oxidation of high-S and high-As gold concentrate].

Science.gov (United States)

Yang, Caiyun; Dong, Bowen; Wang, Meijun; Ye, Zhiyong; Zheng, Tianling; Huang, Huaiguo

2015-12-04

To study the effects of temperature and lixivium return on the concentrate bio-oxidation and rate of gold cyanide leaching. The bioleaching of a high-sulphur (S) and high-arsenic (As) refractory gold concentrate was conducted, and we studied the effects of different temperature (40 ° and 45 °C) and lixivium return (0 and 600 mL) on the bio-oxidation efficiency. The bacterial community structure also was investigated by 16S rRNA gene clone library. The results showed that both the temperature and lixivium return significantly influenced the oxidation system. The temperature rising elevated the oxidation level, while the addition of lixivium depressed the oxidation. Dissimilarity and DCA (detrended correspondence analysis) indicated the effect of temperature on oxidation system was much greater than lixivium. The bacterial community was comprised by Acidithiocacillus caldu (71%) Leptospirillum ferriphilum (23%) and Sulfobacillus thermosulfidooxidans (6%) indicated by the clone library, and the OTU coverage based on 97% sequence similarity was as high as 93.67%. Temperature rising to 45 T would improve the oxidation efficiency while lixivium return would decrease it. This study is helpful to provide an important guiding value for the industry cost optimization of mesophile bacterial oxidation and reduction process.

Polyaspartic Acid Concentration Controls the Rate of Calcium Phosphate Nanorod Formation in High Concentration Systems

Energy Technology Data Exchange (ETDEWEB)

Krogstad, Daniel V. [Biosystems and; Wang, Dongbo [Biosystems and; Lin-Gibson, Sheng [Biosystems and

2017-08-31

Polyelectrolytes are known to greatly affect calcium phosphate (CaP) mineralization. The reaction kinetics as well as the CaP phase, morphology and aggregation state depend on the relative concentrations of the polyelectrolyte and the inorganic ions in a complex, nonlinear manner. This study examines the structural evolution and kinetics of polyaspartic acid (pAsp) directed CaP mineralization at high concentrations of polyelectrolytes, calcium, and total phosphate (19–30 mg/mL pAsp, 50–100 mM Ca2+, Ca/P = 2). Using a novel combination of characterization techniques including cryogenic transmission electron microscopy (cryo-TEM), spectrophotometry, X-ray total scattering pair distribution function analysis, and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), it was determined that the CaP mineralization occurred over four transition steps. The steps include the formation of aggregates of pAsp stabilized CaP spherical nanoparticles (sNP), crystallization of sNP, oriented attachment of the sNP into nanorods, and further crystallization of the nanorods. The intermediate aggregate sizes and the reaction kinetics were found to be highly polymer concentration dependent while the sizes of the particles were not concentration dependent. This study demonstrates the complex role of pAsp in controlling the mechanism as well as the kinetics of CaP mineralization.

Life time fatality risk assessment due to variation of indoor radon concentration in dwellings in western Haryana, India

International Nuclear Information System (INIS)

Kansal, Sandeep; Mehra, Rohit; Singh, N.P.

2012-01-01

Indoor radon measurements in 60 dwellings belonging to 12 villages of Sirsa, Fatehbad and Hisar districts of western Haryana, India, have been carried out, using LR-115 type II cellulose nitrate films in the bare mode. The annual average indoor radon value in the studied area varies from 76.00 to 115.46 Bq m −3 , which is well within the recommended action level 200–300 Bq m −3 (). The winter/summer ratio of indoor radon ranges from 0.78 to 2.99 with an average of 1.52. The values of annual average dose received by the residents and Life time fatality risk assessment due to variation of indoor radon concentration in dwellings of studied area suggests that there is no significance threat to the human beings due to the presence of natural radon in the dwellings. - Highlights: ► The radon concentration values in the dwellings are 2–3 times more than the world average of 40 Bq m −3 . ► These values are lower than the recommended action level of 200–300 Bq m −3 (). ► The annual effective dose is less than the recommended action level of 3–10 mSv per year (). ► The values of life time fatality risk determined for the studied area are within safe standards. ► There is no significant threat to the human beings due to the presence of natural radon in the dwellings.

Selection of common bean lines with high grain yield and high grain calcium and iron concentrations

Directory of Open Access Journals (Sweden)

Nerinéia Dalfollo Ribeiro

2014-02-01

Full Text Available Genetic improvement of common bean nutritional quality has advantages in marketing and can contribute to society as a food source. The objective of this study was to evaluate the genetic variability for grain yield, calcium and iron concentrations in grains of inbred common bean lines obtained by different breeding methods. For this, 136 F7 inbred lines were obtained using the Pedigree method and 136 F7 inbred lines were obtained using the Single-Seed Descent (SSD method. The lines showed genetic variability for grain yield, and concentrations of calcium and iron independently of the method of advancing segregating populations. The Pedigree method allows obtaining a greater number of lines with high grain yield. Selection using the SSD method allows the identification of a larger number of lines with high concentrations of calcium and iron in grains. Weak negative correlations were found between grain yield and calcium concentration (r = -0.0994 and grain yield and iron concentration (r = -0.3926. Several lines show genetic superiority for grain yield and concentrations of calcium and iron in grains and their selection can result in new common bean cultivars with high nutritional quality.

Luminescent passive-oxidized silicon quantum dots as biological staining labels and their cytotoxicity effects at high concentration

International Nuclear Information System (INIS)

Fujioka, Kouki; Manabe, Noriyoshi; Hanada, Sanshiro; Hoshino, Akiyoshi; Yamamoto, Kenji; Hiruoka, Masaki; Sato, Keisuke; Hirakuri, Kenji; Miyasaka, Ryosuke; Tilley, Richard D; Manome, Yoshinobu

2008-01-01

Semiconductor quantum dots (QDs) hold some advantages over conventional organic fluorescent dyes. Due to these advantages, they are becoming increasingly popular in the field of bioimaging. However, recent work suggests that cadmium based QDs affect cellular activity. As a substitute for cadmium based QDs, we have developed photoluminescent stable silicon quantum dots (Si-QDs) with a passive-oxidation technique. Si-QDs (size: 6.5 ± 1.5 nm) emit green light, and they have been used as biological labels for living cell imaging. In order to determine the minimum concentration for cytotoxicity, we investigated the response of HeLa cells. We have shown that the toxicity of Si-QDs was not observed at 112 μg ml -1 and that Si-QDs were less toxic than CdSe-QDs at high concentration in mitochondrial assays and with lactate dehydrogenase (LDH) assays. Especially under UV exposure, Si-QDs were more than ten times safer than CdSe-QDs. We suggest that one mechanism for the cytotoxicity is that Si-QDs can generate oxygen radicals and these radicals are associated with membrane damages. This work has demonstrated the suitability of Si-QDs for bioimaging in lower concentration, and their cytotoxicity and one toxicity mechanism at high concentration

High-concentration planar microtracking photovoltaic system exceeding 30% efficiency

Science.gov (United States)

Price, Jared S.; Grede, Alex J.; Wang, Baomin; Lipski, Michael V.; Fisher, Brent; Lee, Kyu-Tae; He, Junwen; Brulo, Gregory S.; Ma, Xiaokun; Burroughs, Scott; Rahn, Christopher D.; Nuzzo, Ralph G.; Rogers, John A.; Giebink, Noel C.

2017-08-01

Prospects for concentrating photovoltaic (CPV) power are growing as the market increasingly values high power conversion efficiency to leverage now-dominant balance of system and soft costs. This trend is particularly acute for rooftop photovoltaic power, where delivering the high efficiency of traditional CPV in the form factor of a standard rooftop photovoltaic panel could be transformative. Here, we demonstrate a fully automated planar microtracking CPV system 660× concentration ratio over a 140∘ full field of view. In outdoor testing over the course of two sunny days, the system operates automatically from sunrise to sunset, outperforming a 17%-efficient commercial silicon solar cell by generating >50% more energy per unit area per day in a direct head-to-head competition. These results support the technical feasibility of planar microtracking CPV to deliver a step change in the efficiency of rooftop solar panels at a commercially relevant concentration ratio.

Investigation of the areas of high radon concentration in Gyeongju

International Nuclear Information System (INIS)

Lee, Jung Min; Park, Chan Hee; Kim, Shin Jae; Moon, Joo Hyun

2013-01-01

The aim of this study was to survey the radon concentrations at 21 elementary schools in Gyeongju, Republic of Korea, to identify those schools with high radon concentrations. Considering their geological characteristics and the preliminary survey results, three schools were finally placed under close scrutiny. For these three schools, continuous measurements over 48 h were taken at the principal's and administration office. The radon concentrations at one school, Naenam, exceeded the action level (148 Bq/m 3 ) established by the U.S. EPA, while those at the other two schools were below that level. - Highlights: • Preliminary measurements of the indoor radon concentrations were performed at the auditoriums in 23 elementary schools in Gyeongju. • Considering the geological characteristics and preliminary survey results, three elementary schools were screened for closer scrutiny. • For the three schools, continuous measurements were made at their principal's and administration offices over 48-h period. • The scrutiny revealed one elementary school of high radon concentration much higher than the U.S. EPA action level

Selection of antibiotic resistance at very low antibiotic concentrations.

Science.gov (United States)

Sandegren, Linus

2014-05-01

Human use of antibiotics has driven the selective enrichment of pathogenic bacteria resistant to clinically used drugs. Traditionally, the selection of resistance has been considered to occur mainly at high, therapeutic levels of antibiotics, but we are now beginning to understand better the importance of selection of resistance at low levels of antibiotics. The concentration of an antibiotic varies in different body compartments during treatment, and low concentrations of antibiotics are found in sewage water, soils, and many water environments due to natural production and contamination from human activities. Selection of resistance at non-lethal antibiotic concentrations (below the wild-type minimum inhibitory concentration) occurs due to differences in growth rate at the particular antibiotic concentration between cells with different tolerance levels to the antibiotic. The minimum selective concentration for a particular antibiotic is reached when its reducing effect on growth of the susceptible strain balances the reducing effect (fitness cost) of the resistance determinant in the resistant strain. Recent studies have shown that resistant bacteria can be selected at concentrations several hundred-fold below the lethal concentrations for susceptible cells. Resistant mutants selected at low antibiotic concentrations are generally more fit than those selected at high concentrations but can still be highly resistant. The characteristics of selection at low antibiotic concentrations, the potential clinical problems of this mode of selection, and potential solutions will be discussed.

Black carbon concentrations in the highly polluted Kathmandu Valley, Nepal: a three year monitoring with a dual-spot Aethalometer

Science.gov (United States)

Rupakheti, Maheswar; Drinovec, Luka; Puppala, SivaPraveen; Mahata, Khadak; Rupakheti, Dipesh; Kathayat, Bhogendra; Singdan, Pratik; Panday, Arnico; Lawrence, Mark

2016-04-01

Our knowledge about ambient black carbon (BC) in the vast Himalayan region, a region vulnerable to impacts of global warming, is very limited due to unavailability of a long-term ambient monitoring. Here we present results from a continuous monitoring of ambient BC concentrations, with a new generation Aethalometer (AE33), over a three year period (January 2013- January 2016) at a semi-urban site in the highly polluted Kathmandu Valley in the foothills of the central Himalaya, one of the most polluted cities in the world. This is the longest time series of BC concentrations that have been monitored with AE33 (which uses the dual-spot technique for a real-time filter loading compensation) in highly polluted ambient environment. The measurements were carried out under the framework of project SusKat (Sustainable Atmosphere for the Kathmandu Valley). BC concentrations were found to be extremely high, especially in winter and the pre-monsoon period, with the hourly-averaged values often exceeding 50 μg/m3. BC concentrations showed a clear diurnal cycle with a prominent peak around 8-9 am and a second peak around 8-9 pm local time in all four seasons. Night-time BC was also fairly high. The diurnal cycle was driven by a combination of increased emissions from traffic, cooking activities, garbage burning, and lower mixing heights (˜200 m) and reduced horizontal ventilation in the mornings and evenings. BC concentrations showed significant seasonal variations - a maximum in winter season and minimum during the monsoon (rainy) season, with monthly average values in the range 5-30 μg/m3. An increase in emissions from the operation of over 100 brick kilns in winter and spring, and an increase in the use of small but numerous diesel power generators during hours with power cuts contributed significantly to ambient BC concentrations in the valley. Fractional contributions of biomass burning and fossil fuel combustion to BC was estimated based on a real-time method for

Highly concentrated zinc oxide nanocrystals sol with strong blue emission

International Nuclear Information System (INIS)

Vafaee, M.; Sasani Ghamsari, M.; Radiman, S.

2011-01-01

Highly concentrated ZnO sol was synthesized by an improved sol-gel method. Water was used as a modifier to control the sol-gel reaction and provide a way to increase the sol concentration. Concentration of ZnO in the prepared sol is higher than from other methods. Optical absorption and photoluminescence were used to investigate optical properties of the prepared sol. FTIR test was performed to study the influence of water on the compounds of as-prepared sol. The size and morphology of ZnO nanoparticles have been studied by HRTEM. The prepared colloidal ZnO nanocrystals have narrow size distribution (5-8 nm) and showed strong blue emission. The prepared sol has enough potential for optoelectronic applications. - Research highlights: → Novel sol-gel route has been employed to prepare highly concentrated ZnO colloidal nanocrystals. → Water has been used to control the sources of emission in synthesized material. → A strong blue luminescent material has been obtained.

Development and impact of hooks of high droplet concentration on remote southeast Pacific stratocumulus

Directory of Open Access Journals (Sweden)

R. C. George

2013-07-01

Full Text Available Over the southeastern Pacific (SEP, droplet concentration (Nd in the typically unpolluted marine stratocumulus west of 80° W (> 1000 km offshore is periodically strongly enhanced in zonally elongated "hook"-shaped features that increase albedo. Here, we examine three hook events using the chemistry version of the Weather Research and Forecasting model (WRF-Chem with 14 km horizontal resolution, satellite data, and aircraft data from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx. A particularly strong hook yields insights into the development, decay, and radiative impact of these features. Hook development occurs with Nd increasing to polluted levels over the remote ocean primarily due to entrainment of cloud condensation nuclei (CCN from the lower free troposphere (FT. The feature advects northwestward until the FT CCN source is depleted, after which Nd decreases over a few days due to precipitation and dilution. The model suggests that the FT CCN source supplying the hook consists of high concentrations of small accumulation-mode aerosols that contribute a relatively small amount of aerosol mass to the MBL, in agreement with near-coast VOCALS measurements of polluted layers in the FT. The aerosol particles in this hook originate mainly from a pulse of offshore flow that transports Santiago-region (33–35° S emissions to the remote marine FT. To provide pollution CCN that can sustain hooks, the FT transport of pollution plumes to the remote ocean requires strong, deep offshore flow. Such flow is favored by a trough approaching the South American coast and a southeastward shift of the climatological subtropical high-pressure system. The model simulations show precipitation suppression in the hook and a corresponding increase in liquid water path (LWP compared with a simulation without anthropogenic sources. LWP also increases as the hook evolves over time due to increasing stability and decreasing subsidence. WRF

Efficient purification and concentration of viruses from a large body of high turbidity seawater.

Science.gov (United States)

Sun, Guowei; Xiao, Jinzhou; Wang, Hongming; Gong, Chaowen; Pan, Yingjie; Yan, Shuling; Wang, Yongjie

2014-01-01

Marine viruses are the most abundant entities in the ocean and play crucial roles in the marine ecological system. However, understanding of viral diversity on large scale depends on efficient and reliable viral purification and concentration techniques. Here, we report on developing an efficient method to purify and concentrate viruses from large body of high turbidity seawater. The developed method characterizes with high viral recovery efficiency, high concentration factor, high viral particle densities and high-throughput, and is reliable for viral concentration from high turbidity seawater. Recovered viral particles were used directly for subsequent analysis by epifluorescence microscopy, transmission electron microscopy and metagenomic sequencing. Three points are essential for this method:•The sampled seawater (>150 L) was initially divided into two parts, water fraction and settled matter fraction, after natural sedimentation.•Both viruses in the water fraction concentrated by tangential flow filtration (TFF) and viruses isolated from the settled matter fraction were considered as the whole viral community in high turbidity seawater.•The viral concentrates were re-concentrated by using centrifugal filter device in order to obtain high density of viral particles.

Estimation of thorium intake due to consumption of vegetables by inhabitants of high background radiation area by INAA

International Nuclear Information System (INIS)

Sathyapriya, R.S.; Suma Nair; Prabhath, R.K.; Madhu Nair; Rao, D.D.

2012-01-01

A study was conducted to estimate the thorium concentration in locally grown vegetables in high background radiation area (HBRA) of southern coastal regions of India. Locally grown vegetables were collected from HBRA of southern coastal regions of India. Thorium concentration was quantified using instrumental neutron activation analysis. The samples were irradiated at CIRUS reactor and counted using a 40% relative efficiency HPGe detector coupled to MCA. The annual intake of thorium was evaluated using the consumption data provided by National Nutrition Monitoring Board. The daily intake of 232 Th from the four food categories (green leafy vegetables, others vegetables, roots and tubers, and fruits) ranged between 0.27 and 5.352 mBq d -1 . The annual internal dose due to ingestion of thorium from these food categories was 46.8 x 10 -8 for female and 58.6 x 10 -8 Sv y -1 for male. (author)

A compact spectrum splitting concentrator for high concentration photovoltaics based on the dispersion of a lens

Science.gov (United States)

He, J.; Flowers, C. A.; Yao, Y.; Atwater, H. A.; Rockett, A. A.; Nuzzo, R. G.

2018-06-01

Photovoltaic devices used in conjunction with functional optical elements for light concentration and spectrum splitting are known to be a viable approach for highly efficient photovoltaics. Conventional designs employ discrete optical elements, each with the task of either performing optical concentration or separating the solar spectrum. In the present work, we examine the performance of a compact photovoltaic architecture in which a single lens plays a dual role as both a concentrator and a spectrum splitter, the latter made possible by exploiting its intrinsic dispersion. A four-terminal two-junction InGaP/GaAs device is prepared to validate the concept and illustrates pathways for improvements. A spectral separation in the visible range is demonstrated at the focal point of a plano-convex lens with a geometric concentration ratio of 1104X with respect to the InGaP subcell.

Gravitational settling of a highly concentrated system of solid spherical particles

Science.gov (United States)

Arkhipov, V. A.; Usanina, A. S.

2017-09-01

In the present paper, we report on the results of an experimental study of the process of gravity sedimentation of a cloud of monodispersed solid spherical particles with initial volume concentration C > 0.03, which was performed in a wide range of Reynolds numbers. An analytical estimate of the settling regimes of spherical particle clouds is presented. A new method for creating a spherical particle cloud with a high concentration of particles is proposed. A qualitative picture of the settling process of a highly concentrated particle cloud under gravity is revealed. A criterial dependence for the drag coefficient of a sedimenting spherical particle cloud as an entity is obtained.

High Voltage Solar Concentrator Experiment with Implications for Future Space Missions

Science.gov (United States)

Mehdi, Ishaque S.; George, Patrick J.; O'Neill, Mark; Matson, Robert; Brockschmidt, Arthur

2004-01-01

This paper describes the design, development, fabrication, and test of a high performance, high voltage solar concentrator array. This assembly is believed to be the first ever terrestrial triple-junction-cell solar array rated at over 1 kW. The concentrator provides over 200 W/square meter power output at a nominal 600 Vdc while operating under terrestrial sunlight. Space-quality materials and fabrication techniques were used for the array, and the 3005 meter elevation installation below the Tropic of Cancer allowed testing as close as possible to space deployment without an actual launch. The array includes two concentrator modules, each with a 3 square meter aperture area. Each concentrator module uses a linear Fresnel lens to focus sunlight onto a photovoltaic receiver that uses 240 series-connected triple-junction solar cells. Operation of the two receivers in series can provide 1200 Vdc which would be adequate for the 'direct drive' of some ion engines or microwave transmitters in space. Lens aperture width is 84 cm and the cell active width is 3.2 cm, corresponding to a geometric concentration ratio of 26X. The evaluation includes the concentrator modules, the solar cells, and the materials and techniques used to attach the solar cells to the receiver heat sink. For terrestrial applications, a finned aluminum extrusion was used for the heat sink for the solar cells, maintaining a low cell temperature so that solar cell efficiency remains high.

Mitigation of houses with extremely high indoor radon concentrations

International Nuclear Information System (INIS)

Jiranek, M.; Neznal, M.

2006-01-01

Full text of publication follows: The paper reports on the experience of the Czech Technical University in dealing with mitigation of houses in which unusually high indoor radon concentrations were found. The whole process of remediation is illustrated by example of an old single-family house that was built in the area formed by highly permeable soils with high radon content in the soil air. T he house has a small cellar located under 1/5 of the ground floor area. Two types of floors, i.e. timber floors and cracked concrete slabs were found in the house. As a result of extremely high radon concentration in the sub-floor region (up to 600 kBq/m 3 ) and leaky structures in contact with soil, radon concentrations around 100 kBq/m 3 in the cellar and up to 60 kBq/m 3 in the living rooms on the ground floor were measured prior to mitigation. Mitigation measures that were carried out in the house consist of reconstruction of timber floors and installation of active soil depressurization. Timber floors were replaced with concrete slab fitted with damp proof membrane, thermal insulation and floor covering. The soil depressurization system was made up of two sections. The first section is composed of the network of perforated pipes inserted in the drainage layer placed under the new floors and four perforated tubes drilled under the existing floors. The soil air from this section is extracted by means of a roof fan installed at the top of the vertical exhaust pipe running inside the living space and terminating above the roof. The second section was designed to withdraw by means of a small fan radon-laden air from the filling in the floor above the cellar and from perforated tubes drilled into the sub-floor region under the rooms adjacent to the cellar. It serves also for the active ventilation of the cellar. Pressure, temperature and radon concentration sensors were installed into the drainage layer during the reconstruction of floors to record variations in these

Concentration of High Level Radioactive Liquid Waste. Basic data acquisition

Energy Technology Data Exchange (ETDEWEB)

Juvenelle, A.; Masson, M.; Garrido, M.H. [DEN/VRH/DRCP/SCPS/LPCP, BP 17171 - 30207 Bagnols sur Ceze Cedex (France)

2008-07-01

Full text of publication follows: In order to enhance its knowledge about the concentration of high level liquid waste (HLLW) from the nuclear fuel reprocessing process, a program of studies was defined by Cea. In a large field of acidity, it proposes to characterize the concentrated solution and the obtained precipitates versus the concentration factor. Four steps are considered: quantification of the salting-out effect on the concentrate acidity, acquisition of solubility data, precipitates characterisation versus the concentration factor through aging tests and concentration experimentation starting from simulated fission products solutions. The first results, reported here, connect the acidity of the concentrated solution to the concentration factor and allow us to precise the field of acidity (4 to 12 N) for the next experiments. In this field, solubility data of various elements (Ba, Sr, Zr...) are separately measured at room temperature, in nitric acid in a first time, then in the presence of various species present in medium (TBP, PO{sub 4}{sup 3-}). The reactions between these various elements are then investigated (formation of insoluble mixed compounds) by following the concentration cations in solution and characterising the precipitates. (authors)

High surface hole concentration p-type GaN using Mg implantation

International Nuclear Information System (INIS)

Long Tao; Yang Zhijian; Zhang Guoyi

2001-01-01

Mg ions were implanted on Mg-doped GaN grown by metalorganic chemical vapor deposition (MOCVD). The p-type GaN was achieved with high hole concentration (8.28 x 10 17 cm -3 ) conformed by Van derpauw Hall measurement after annealing at 800 degree C for 1 h. this is the first experimental report of Mg implantation on Mg-doped GaN and achieving p-type GaN with high surface hole concentration

Rheology of dilute acid hydrolyzed corn stover at high solids concentration.

Science.gov (United States)

Ehrhardt, M R; Monz, T O; Root, T W; Connelly, R K; Scott, C T; Klingenberg, D J

2010-02-01

The rheological properties of acid hydrolyzed corn stover at high solids concentration (20-35 wt.%) were investigated using torque rheometry. These materials are yield stress fluids whose rheological properties can be well represented by the Bingham model. Yield stresses increase with increasing solids concentration and decrease with increasing hydrolysis reaction temperature, acid concentration, and rheometer temperature. Plastic viscosities increase with increasing solids concentration and tend to decrease with increasing reaction temperature and acid concentration. The solids concentration dependence of the yield stress is consistent with that reported for other fibrous systems. The changes in yield stress with reaction conditions are consistent with observed changes in particle size. This study illustrates that torque rheometry can be used effectively to measure rheological properties of concentrated biomass.

An attempt to explain strength increase due to high loading rates

International Nuclear Information System (INIS)

Eibl, J.; Curbach, M.

1989-01-01

Most materials such as steel, concrete, ceramics, polymers, etc. show an increase of strength due to high loading rates. A number of mathematical equations are available to describe this behaviour. Nevertheless the physical reasons for these observations are still unknown. The common behaviour of a number of materials leads to the assumption that at least some explanations are material independent. Due to this reason the results of the research done at the Institute for Concrete Structures in Karlsruhe are presented in this paper to furnish new ideas for the material research due to dynamic loading. (orig.)

Prodigious Effects of Concentration Intensification on Nanoparticle Synthesis: A High-Quality, Scalable Approach

KAUST Repository

Williamson, Curtis B.

2015-12-23

© 2015 American Chemical Society. Realizing the promise of nanoparticle-based technologies demands more efficient, robust synthesis methods (i.e., process intensification) that consistently produce large quantities of high-quality nanoparticles (NPs). We explored NP synthesis via the heat-up method in a regime of previously unexplored high concentrations near the solubility limit of the precursors. We discovered that in this highly concentrated and viscous regime the NP synthesis parameters are less sensitive to experimental variability and thereby provide a robust, scalable, and size-focusing NP synthesis. Specifically, we synthesize high-quality metal sulfide NPs (<7% relative standard deviation for Cu2-xS and CdS), and demonstrate a 10-1000-fold increase in Cu2-xS NP production (>200 g) relative to the current field of large-scale (0.1-5 g yields) and laboratory-scale (<0.1 g) efforts. Compared to conventional synthesis methods (hot injection with dilute precursor concentration) characterized by rapid growth and low yield, our highly concentrated NP system supplies remarkably controlled growth rates and a 10-fold increase in NP volumetric production capacity (86 g/L). The controlled growth, high yield, and robust nature of highly concentrated solutions can facilitate large-scale nanomanufacturing of NPs by relaxing the synthesis requirements to achieve monodisperse products. Mechanistically, our investigation of the thermal and rheological properties and growth rates reveals that this high concentration regime has reduced mass diffusion (a 5-fold increase in solution viscosity), is stable to thermal perturbations (64% increase in heat capacity), and is resistant to Ostwald ripening.

Quantified Hole Concentration in AlGaN Nanowires for High-Performance Ultraviolet Emitters

KAUST Repository

Zhao, Chao; Ebaid, Mohamed; Zhang, Huafan; Priante, Davide; Janjua, Bilal; Zhang, Daliang; Wei, Nini; Alhamoud, Abdullah; Shakfa, M. Khaled; Ng, Tien Khee; Ooi, Boon S.

2018-01-01

P-type doping in wide bandgap and new classes of ultra-wide bandgap materials has long been a scientific and engineering problem. The challenges arise from the large activation energy of dopants and high densities of dislocations in materials. We report here, a significantly enhanced p-type conduction using high-quality AlGaN nanowires. For the first time, the hole concentration in Mg-doped AlGaN nanowires is quantified. The incorporation of Mg into AlGaN was verified by correlation with photoluminescence and Raman measurements. The open-circuit potential measurements further confirmed the p-type conductivity; while Mott-Schottky experiments measured a hole concentration of 1.3×1019 cm-3. These results from photoelectrochemical measurements allow us to design prototype ultraviolet (UV) light-emitting diodes (LEDs) incorporating the AlGaN quantum-disks-in-nanowire and optimized p-type AlGaN contact layer for UV-transparency. The ~335-nm LEDs exhibited a low turn-on voltage of 5 V with a series resistance of 32 Ω, due to the efficient p-type doping of the AlGaN nanowires. The bias-dependent Raman measurements further revealed the negligible self-heating of devices. This study provides an attractive solution to evaluate electrical properties of AlGaN, which is applicable to other wide bandgap nanostructures. Our results are expected to open doors to new applications for wide and ultra-wide bandgap materials.

Quantified Hole Concentration in AlGaN Nanowires for High-Performance Ultraviolet Emitters

KAUST Repository

Zhao, Chao

2018-05-29

P-type doping in wide bandgap and new classes of ultra-wide bandgap materials has long been a scientific and engineering problem. The challenges arise from the large activation energy of dopants and high densities of dislocations in materials. We report here, a significantly enhanced p-type conduction using high-quality AlGaN nanowires. For the first time, the hole concentration in Mg-doped AlGaN nanowires is quantified. The incorporation of Mg into AlGaN was verified by correlation with photoluminescence and Raman measurements. The open-circuit potential measurements further confirmed the p-type conductivity; while Mott-Schottky experiments measured a hole concentration of 1.3×1019 cm-3. These results from photoelectrochemical measurements allow us to design prototype ultraviolet (UV) light-emitting diodes (LEDs) incorporating the AlGaN quantum-disks-in-nanowire and optimized p-type AlGaN contact layer for UV-transparency. The ~335-nm LEDs exhibited a low turn-on voltage of 5 V with a series resistance of 32 Ω, due to the efficient p-type doping of the AlGaN nanowires. The bias-dependent Raman measurements further revealed the negligible self-heating of devices. This study provides an attractive solution to evaluate electrical properties of AlGaN, which is applicable to other wide bandgap nanostructures. Our results are expected to open doors to new applications for wide and ultra-wide bandgap materials.

Isopleths of surface air concentration and surface air kerma rate due to a radioactive cloud released from a stack (3)

International Nuclear Information System (INIS)

Tachibana, Haruo; Kikuchi, Masamitsu; Sekita, Tsutomu; Yamaguchi, Takenori

2004-06-01

This report is a revised edition of 'Isopleths of Surface Air Concentration and Surface Air Absorbed Dose Rate due to a Radioactive Cloud Released from a Stack(II) '(JAERI-M 90-206) and based on the revised Nuclear Safety Guidelines reflected the ICRP1990 Recommendation. Characteristics of this report are the use of Air Karma Rate (Gy/h) instead of Air Absorbed Dose Rate (Gy/h), and the record of isopleths of surface air concentration and surface air karma rate on CD-ROM. These recorded data on CD-ROM can be printed out on paper and/or pasted on digital map by personal computer. (author)

Development of Concentration and Calcination Technology For High Level Liquid Waste

International Nuclear Information System (INIS)

Pande, D.P.

2006-01-01

The concentrated medium and high-level liquid radio chemicals effluents contain nitric acid, water along with the dissolved chemicals including the nitrates of the radio nuclides. High level liquid waste contain mainly nitrates of cesium, strontium, cerium, zirconium, chromium, barium, calcium, cobalt, copper, pickle, iron etc. and other fission products. This concentrated solution requires further evaporation, dehydration, drying and decomposition in temperature range of 150 to 700 deg. C. The addition of the calcined solids in vitrification pot, instead of liquid feed, helps to avoid low temperature zone because the vaporization of the liquid and decomposition of nitrates do not take place inside the melter. In our work Differential and thermo gravimetric studies has been carried out in the various stages of thermal treatment including drying, dehydration and conversion to oxide forms. Experimental studies were done to characterize the chemicals present in high-level radioactive waste. A Rotary Ball Kiln Calciner was used for development of the process because this is amenable for continuous operation and moderately good heat transfer can be achieved inside the kiln. This also has minimum secondary waste and off gases generation. The Rotary Ball Kiln Calciner Demonstration facility system was designed and installed for the demonstration of calcination process. The Rotary Ball Kiln Calciner is a slowly rotating slightly inclined horizontal tube that is externally heated by means of electric resistance heating. The liquid feed is sprayed onto the moving bed of metal balls in a slowly rotating calciner by a peristaltic type-metering pump. The vaporization of the liquid occurs in the pre-calcination zone due to counter current flow of hot gases. The dehydration and denitration of the solids occurs in the calcination zone, which is externally heated by electrical furnace. The calcined powder is cooled in the post calcination portion. It has been demonstrated that the

Diverse microbial species survive high ammonia concentrations

Science.gov (United States)

Kelly, Laura C.; Cockell, Charles S.; Summers, Stephen

2012-04-01

Planetary protection regulations are in place to control the contamination of planets and moons with terrestrial micro-organisms in order to avoid jeopardizing future scientific investigations relating to the search for life. One environmental chemical factor of relevance in extraterrestrial environments, specifically in the moons of the outer solar system, is ammonia (NH3). Ammonia is known to be highly toxic to micro-organisms and may disrupt proton motive force, interfere with cellular redox reactions or cause an increase of cell pH. To test the survival potential of terrestrial micro-organisms exposed to such cold, ammonia-rich environments, and to judge whether current planetary protection regulations are sufficient, soil samples were exposed to concentrations of NH3 from 5 to 35% (v/v) at -80°C and room temperature for periods up to 11 months. Following exposure to 35% NH3, diverse spore-forming taxa survived, including representatives of the Firmicutes (Bacillus, Sporosarcina, Viridibacillus, Paenibacillus, Staphylococcus and Brevibacillus) and Actinobacteria (Streptomyces). Non-spore forming organisms also survived, including Proteobacteria (Pseudomonas) and Actinobacteria (Arthrobacter) that are known to have environmentally resistant resting states. Clostridium spp. were isolated from the exposed soil under anaerobic culture. High NH3 was shown to cause a reduction in viability of spores over time, but spore morphology was not visibly altered. In addition to its implications for planetary protection, these data show that a large number of bacteria, potentially including spore-forming pathogens, but also environmentally resistant non-spore-formers, can survive high ammonia concentrations.

High frequency measurement of nitrate concentration in the Lower Mississippi River, USA

Science.gov (United States)

Duan, Shuiwang; Powell, Rodney T.; Bianchi, Thomas S.

2014-11-01

Nutrient concentrations in the Mississippi River have increased dramatically since the 1950s, and high frequency measurements on nitrate concentration are required for accurate load estimations and examinations on nitrate transport and transformation processes. This three year record of high temporal resolution (every 2-3 h) data clearly illustrates the importance of high frequency sampling in improving load estimates and resolving variations in nitrate concentration with river flow and tributary inputs. Our results showed large short-term (days to weeks) variations in nitrate concentration but with no diurnal patterns. A repeatable and pronounced seasonal pattern of nitrate concentration was observed, and showed gradual increases from the lowest values in September (during base-flow), to the highest in June - which was followed by a rapid decrease. This seasonal pattern was only moderately linked with water discharge, and more controlled by nitrogen transformation/export from watershed as well as mixing patterns of the two primary tributaries (the upper Mississippi and the Ohio Rivers), which have distinctly different nitrate concentrations and flow patterns. Based on continuous in situ flow measurements, we estimated 554-886 × 106 kg of nitrate-N was exported from the Mississippi River system during years 2004-2006, which was <9% and <16% lower than U.S. Geological Survey's (USGS) estimates using their LOADEST or composite methods, respectively. USGS methods generally overestimated nitrate loads during rising stages and underestimated the loads during falling stages. While changes in nitrate concentrations in large rivers are generally not as responsive to alterations in diurnal inputs and/or watershed hydrology as small rivers, high-frequency water quality sampling would help in monitoring short-term (days to weeks) variations in nutrient concentration patterns and thus improve the accuracy of nutrient flux estimates.

The Effect of Concentration of P-phenylenediamine Antioxidant on the Acrylonitrile-Butadiene Rubber Seals under High Gamma Irradiation

International Nuclear Information System (INIS)

Hegazi, E.M.; Abd El-megeed, A.A.

2016-01-01

Acrylonitrile- butadiene rubber (NBR) seals are one of the classified seals used in nuclear facilities. But at high irradiation doses the physical and mechanical properties of NBR are adversely affected due to the degradation induced by radiation and hence affect the sealing performance reducing their service life. The present work is focused on studying the effect of concentration of N-(1, 3-dimethylbutyl)-N’-phenyl-p-phenylene diamine (6PPD) on the physical and mechanical properties of the NBR rubber at high doses of γ-irradiation up to 2 MGy. The physical properties, mechanical properties, hardness, and abrasion of the NBR rubber under γ-radiation were investigated. The optimum amount of 6PPD required to resist deterioration is also estimated. The results showed a remarkable increase in the physical and mechanical properties as the concentration of 6PPD was increased from 1 phr (part per hundred) to 3 phr in NBR samples

Evaluation of radionuclide concentrations in high-level radioactive wastes

International Nuclear Information System (INIS)

Fehringer, D.J.

1985-10-01

This report describes a possible approach for development of a numerical definition of the term ''high-level radioactive waste.'' Five wastes are identified which are recognized as being high-level wastes under current, non-numerical definitions. The constituents of these wastes are examined and the most hazardous component radionuclides are identified. This report suggests that other wastes with similar concentrations of these radionuclides could also be defined as high-level wastes. 15 refs., 9 figs., 4 tabs

High surface hole concentration p-type GaN using Mg implantation

CERN Document Server

Long Tao; Zhang Guo Yi

2001-01-01

Mg ions were implanted on Mg-doped GaN grown by metalorganic chemical vapor deposition (MOCVD). The p-type GaN was achieved with high hole concentration (8.28 x 10 sup 1 sup 7 cm sup - sup 3) conformed by Van derpauw Hall measurement after annealing at 800 degree C for 1 h. this is the first experimental report of Mg implantation on Mg-doped GaN and achieving p-type GaN with high surface hole concentration

High Efficiency Nanostructured III-V Photovoltaics for Solar Concentrator Application

Energy Technology Data Exchange (ETDEWEB)

Hubbard, Seth

2012-09-12

The High Efficiency Nanostructured III-V Photovoltaics for Solar Concentrators project seeks to provide new photovoltaic cells for Concentrator Photovoltaics (CPV) Systems with higher cell efficiency, more favorable temperature coefficients and less sensitivity to changes in spectral distribution. The main objective of this project is to provide high efficiency III-V solar cells that will reduce the overall cost per Watt for power generation using CPV systems.This work is focused both on a potential near term application, namely the use of indium arsenide (InAs) QDs to spectrally "tune" the middle (GaAs) cell of a SOA triple junction device to a more favorable effective bandgap, as well as the long term goal of demonstrating intermediate band solar cell effects. The QDs are confined within a high electric field i-region of a standard GaAs solar cell. The extended absorption spectrum (and thus enhanced short circuit current) of the QD solar cell results from the increase in the sub GaAs bandgap spectral response that is achievable as quantum dot layers are introduced into the i-region. We have grown InAs quantum dots by OMVPE technique and optimized the QD growth conditions. Arrays of up to 40 layers of strain balanced quantum dots have been experimentally demonstrated with good material quality, low residual stain and high PL intensity. Quantum dot enhanced solar cells were grown and tested under simulated one sun AM1.5 conditions. Concentrator solar cells have been grown and fabricated with 5-40 layers of QDs. Testing of these devices show the QD cells have improved efficiency compared to baseline devices without QDs. Device modeling and measurement of thermal properties were performed using Crosslight APSYS. Improvements in a triple junction solar cell with the insertion of QDs into the middle current limiting junction was shown to be as high as 29% under one sun illumination for a 10 layer stack QD enhanced triple junction solar cell. QD devices have strong

Relationships Between Land Use and Stream Nutrient Concentrations in a Highly Urbanized Tropical Region of Brazil: Thresholds and Riparian Zones.

Science.gov (United States)

Tromboni, F; Dodds, W K

2017-07-01

Nutrient enrichment in streams due to land use is increasing globally, reducing water quality and causing eutrophication of downstream fresh and coastal waters. In temperate developed countries, the intensive use of fertilizers in agriculture is a main driver of increasing nutrient concentrations, but high levels and fast rates of urbanization can be a predominant issue in some areas of the developing world. We investigated land use in the highly urbanized tropical State of Rio de Janeiro, Brazil. We collected total nitrogen, total phosphorus, and inorganic nutrient data from 35 independent watersheds distributed across the State and characterized land use at a riparian and entire watershed scales upstream from each sample station, using ArcGIS. We used regression models to explain land use influences on nutrient concentrations and to assess riparian protection relationships to water quality. We found that urban land use was the primary driver of nutrient concentration increases, independent of the scale of analyses and that urban land use was more concentrated in the riparian buffer of streams than in the entire watersheds. We also found significant thresholds that indicated strong increases in nutrient concentrations with modest increases in urbanization reaching maximum nutrient concentrations between 10 and 46% urban cover. These thresholds influenced calculation of reference nutrient concentrations, and ignoring them led to higher estimates of these concentrations. Lack of sewage treatment in concert with urban development in riparian zones apparently leads to the observation that modest increases in urban land use can cause large increases in nutrient concentrations.

High mobility and high concentration Type-III heterojunction FET

Science.gov (United States)

Tsu, R.; Fiddy, M. A.; Her, T.

2018-02-01

The PN junction was introduced in transistors by doping, resulting in high losses due to Coulomb scattering from the dopants. The MOSFET introduced carriers in the form of electrons and holes with an applied bias to the oxide barrier, resulting in carrier transfer without doping. This avoids high scattering losses and dominates the IC industries. With heterojunctions having valence-band maxima near and even above the conduction-band minimum in the formation of Type-III superlattices, very useful devices, introduced by Tsu, Sai-Halacz, and Esaki, soon followed. If the layer thicknesses are more than the carrier mean-free-path, incoherent scattering results in the formation of carrier transfer via diffusion instead of opening up new energy gaps. The exploitation of carriers without scattering represents a new and significant opportunity in what we call a Broken Gap Heterojunction FET.

Starch source in high concentrate rations does not affect rumen pH, histamine and lipopolysaccharide concentrations in dairy cows

NARCIS (Netherlands)

Pilachai, R.; Schonewille, J.T.; Thamrongyoswittayakul, C.; Aiumlamai, S.; Wachirapakom, C.; Everts, H.; Hendriks, W.H.

2012-01-01

The replacement of ground corn by cassava meal on rumen pH, lipopolysaccharide (LPS) and histamine concentrations under typical Thai feeding conditions (high concentrate diets and rice straw as the sole source of roughage) was investigated. Four rumen-fistulated crossbred Holstein, non-pregnant, dry

Magnetic concentration of iron-titanium ore with vanadium concentrate from campo Alegre de Lourdes - Bahia, Brazil

International Nuclear Information System (INIS)

Delgado, O.; Silva, F.T. da; Ogasawara, T.; Soares, G.F.

1988-01-01

The feasibility studies of magnetic concentration of the Campo Alegre de Lourdes ore were carried out, trying to obtain a maximum recovery of vanadium. As a consequence of the complex nature of the ore, mainly due to the presence of ilmenite as a exolutions in the interior of hematite/martite particles, it was not possible to separate the hematite-ilmenite eficiently, wich would be necessary for obtaining a high grade vanadium concentrate with low titanium content. (author) [pt

Resting serum concentration of high-sensitivity C-reactive protein ...

African Journals Online (AJOL)

Resting serum concentration of high-sensitivity C-reactive protein (hs-CRP) in sportsmen and untrained male adults. F.A. Niyi-Odumosu, O. A. Bello, S.A. Biliaminu, B.V. Owoyele, T.O. Abu, O.L. Dominic ...

High concentration of vitamin E decreases thermosensation and thermotaxis learning and the underlying mechanisms in the nematode Caenorhabditis elegans.

Science.gov (United States)

Li, Yiping; Li, Yinxia; Wu, Qiuli; Ye, Huayue; Sun, Lingmei; Ye, Boping; Wang, Dayong

2013-01-01

α-tocopherol is a powerful liposoluble antioxidant and the most abundant isoform of vitamin E in the body. Under normal physiological conditions, adverse effects of relatively high concentration of vitamin E on organisms and the underlying mechanisms are still largely unclear. In the present study, we used the nematode Caenorhabditis elegans as an in vivo assay system to investigate the possible adverse effects of high concentration of vitamin E on thermosensation and thermotaxis learning and the underlying mechanisms. Our data show that treatment with 100-200 µg/mL of vitamin E did not noticeably influence both thermosensation and thermotaxis learning; however, treatment with 400 µg/mL of vitamin E altered both thermosensation and thermotaxis learning. The observed decrease in thermotaxis learning in 400 µg/mL of vitamin E treated nematodes might be partially due to the moderate but significant deficits in thermosensation, but not due to deficits in locomotion behavior or perception to food and starvation. Treatment with 400 µg/mL of vitamin E did not noticeably influence the morphology of GABAergic neurons, but significantly decreased fluorescent intensities of the cell bodies in AFD sensory neurons and AIY interneurons, required for thermosensation and thermotaxis learning control. Treatment with 400 µg/mL of vitamin E affected presynaptic function of neurons, but had no remarkable effects on postsynaptic function. Moreover, promotion of synaptic transmission by activating PKC-1 effectively retrieved deficits in both thermosensation and thermotaxis learning induced by 400 µg/mL of vitamin E. Therefore, relatively high concentrations of vitamin E administration may cause adverse effects on thermosensation and thermotaxis learning by inducing damage on the development of specific neurons and presynaptic function under normal physiological conditions in C. elegans.

Nonfaradaic nanoporous electrochemistry for conductometry at high electrolyte concentration.

Science.gov (United States)

Bae, Je Hyun; Kang, Chung Mu; Choi, Hyoungseon; Kim, Beom Jin; Jang, Woohyuk; Lim, Sung Yul; Kim, Hee Chan; Chung, Taek Dong

2015-02-17

Nanoporous electrified surfaces create a unique nonfaradaic electrochemical behavior that is sensitively influenced by pore size, morphology, ionic strength, and electric field modulation. Here, we report the contributions of ion concentration and applied ac frequency to the electrode impedance through an electrical double layer overlap and ion transport along the nanopores. Nanoporous Pt with uniform pore size and geometry (L2-ePt) responded more sensitively to conductivity changes in aqueous solutions than Pt black with poor uniformity despite similar real surface areas and enabled the previously difficult quantitative conductometry measurements at high electrolyte concentrations. The nanopores of L2-ePt were more effective in reducing the electrode impedance and exhibited superior linear responses to not only flat Pt but also Pt black, leading to successful conductometric detection in ion chromatography without ion suppressors and at high ionic strengths.

Isopleths of surface concentration and surface exposure rate due to a radioactive cloud released from a stack

International Nuclear Information System (INIS)

Kobayashi, Hideo; Yabuta, Hajimu; Katagiri, Hiroshi; Obata, Kazuichi; Kokubu, Morinobu

1982-03-01

Various calculations are made to estimate the distributions of concentration and γ-exposure rate due to a radioactive cloud released from a point source to the atmosphere. In this report, the isopleths of concentration and γ-exposure rate which were calculated are given in graphs to enable rapid prediction of the influence of released radioactive material in the emergency situation. Recently there are facilities which are equipped with a system to display the calculation results on CRT; but such practice is rather rare. By placing the calculated isopleths of reduction scale 1/25000 or 1/50000 on the usual map, any facilities without the CRT system can readily estimate the influence of an accidental release. The graphs of isopleths are given with the release height (11 values of 0 to 200 m at about 20 m intervals) and the atmospheric stability (6 classes) as parameters. Calculations of γ-exposure rates were made using the computer code GAMPUL developed by T. Hayashi and T. Shiraishi. In the calculation of radioactive concentrations and γ-exposure rates, the vertical diffusion depths, σsub(z), exceeding 1000 m are taken to be 1000 m according to the Meteorological Guide for the Safety Analysis of Power Reactor (J.AEC). The comparison between with and without this limitation in σsub(z) is made in the case of downwind axial surface distributions. (author)

Clearly Transparent Nanopaper from Highly Concentrated Cellulose Nanofiber Dispersion Using Dilution and Sonication

Directory of Open Access Journals (Sweden)

Takaaki Kasuga

2018-02-01

Full Text Available Nanopaper prepared from holocellulose pulp is one of the best substrates for flexible electronics because of its high thermal resistance and high clear transparency. However, the clearness of nanopaper decreases with increasing concentration of the starting cellulose nanofiber dispersion—with the use of a 2.2 wt % dispersion, for example—resulting in translucent nanopaper with a high haze of 44%. To overcome this problem, we show that the dilution of this high-concentration dispersion with water followed by sonication for 10 s reduces the haze to less than 10% while maintaining the high thermal resistance of the nanopaper. Furthermore, the combination of water dilution and a short sonication treatment improves the clearness of the nanopaper, which would translate into cost savings for the transportation and storage of this highly concentrated cellulose nanofiber dispersion. Finally, we demonstrate the improvement of the electrical conductivity of clear transparent nanopaper prepared from an initially high-concentration dispersion by dropping and heating silver nanowire ink on the nanopaper. These achievements will pave the way toward the realization of the mass production of nanofiber-based flexible devices.

Optimum concentric circular array antenna with high gain and side lobe reduction at 5.8 GHz

Science.gov (United States)

Zaid, Mohammed; Rafiqul Islam, Md; Habaebi, Mohamed H.; Zahirul Alam, AHM; Abdullah, Khaizuran

2017-11-01

The significance of high gain directional antennas stems from the need to cope up with the everyday progressing wireless communication systems. Due to low gain of the widely used microstrip antenna, combining multiple antennas in proper geometry increases the gain with good directive property. Over other array forms, this paper uses concentric circular array configuration for its compact structure and inherent symmetry in azimuth. This proposed array is composed of 9 elements on FR-4 substrate, which is designed for WLAN applications at 5.8GHz. Antenna Magus software is used for synthesis, while CST software is used for optimization. The proposed array is designed with optimum inter-element spacing and number of elements achieving a high directional gain of 15.7 dB compared to 14.2 dB of available literature, with a high reduction in side lobe level of -17.6 dB.

High-concentration mirror-based Kohler integrating system for tandem solar cells

Science.gov (United States)

Winston, R.; Benitez, P.; Cvetkovic, A.

2006-06-01

A novel two-mirror high concentration nonimaging optic has been designed that shares the advantages of present two mirror aplanatic imaging concentrators but also overcomes their main limitation of trade-off between acceptance angle and irradiance uniformity. A system concept has been defined, and a first prototype in under development.

The salivary microbiome is altered in the presence of a high salivary glucose concentration.

Directory of Open Access Journals (Sweden)

J Max Goodson

Full Text Available Type II diabetes (T2D has been associated with changes in oral bacterial diversity and frequency. It is not known whether these changes are part of the etiology of T2D, or one of its effects.We measured the glucose concentration, bacterial counts, and relative frequencies of 42 bacterial species in whole saliva samples from 8,173 Kuwaiti adolescents (mean age 10.00 ± 0.67 years using DNA probe analysis. In addition, clinical data related to obesity, dental caries, and gingivitis were collected. Data were compared between adolescents with high salivary glucose (HSG; glucose concentration ≥ 1.0 mg/d, n = 175 and those with low salivary glucose (LSG, glucose concentration < 0.1 mg/dL n = 2,537.HSG was associated with dental caries and gingivitis in the study population. The overall salivary bacterial load in saliva decreased with increasing salivary glucose concentration. Under HSG conditions, the bacterial count for 35 (83% of 42 species was significantly reduced, and relative bacterial frequencies in 27 species (64% were altered, as compared with LSG conditions. These alterations were stronger predictors of high salivary glucose than measures of oral disease, obesity, sleep or fitness.HSG was associated with a reduction in overall bacterial load and alterations to many relative bacterial frequencies in saliva when compared with LSG in samples from adolescents. We propose that hyperglycemia due to obesity and/or T2D results in HSG and subsequent acidification of the oral environment, leading to a generalized perturbation in the oral microbiome. This suggests a basis for the observation that hyperglycemia is associated with an increased risk of dental erosion, dental caries, and gingivitis. We conclude that HSG in adolescents may be predicted from salivary microbial diversity or frequency, and that the changes in the oral microbial composition seen in adolescents with developing metabolic disease may the consequence of hyperglycemia.

Optical losses due to tracking on solar thermal collectors

DEFF Research Database (Denmark)

Sallaberry, Fabienne; Pujol-Nadal, Ramn; Peres, Bengt

2017-01-01

For a wide range of operational temperatures, the solar thermal collectors can use optical concentration systems to optimize their efficiency. However, as optical concentration relies on direct solar radiation, it is necessary to use a solar tracker following the sun direction to maximize...... the amount of useful solar radiation received. The selection of the appropriate tracking systems matching the optical concentration factor is essential to achieve optimal collector efficiency. Otherwise, the concentrator would experience high optical losses due to the inadequate focusing of the direct solar...... radiation onto its receiver, regardless of its quality. This paper gives the state-of-the-art of the methodologies available to characterize the tracking error of a concentrating collector, a summary of different previous studies done in this subject and of the standardization regarding the tracking...

High concentrations of Na+ and Cl- ions in soil solution have simultaneous detrimental effects on growth of faba bean under salinity stress.

Science.gov (United States)

Tavakkoli, Ehsan; Rengasamy, Pichu; McDonald, Glenn K

2010-10-01

the effects of the two ions may differ. High Cl(-) concentration reduces the photosynthetic capacity and quantum yield due to chlorophyll degradation which may result from a structural impact of high Cl(-) concentration on PSII. High Na(+) interferes with K(+) and Ca(2+) nutrition and disturbs efficient stomatal regulation which results in a depression of photosynthesis and growth. These results suggest that the importance of Cl(-) toxicity as a cause of reductions in growth and yield under salinity stress may have been underestimated.

Radiation dose-dependent risk on individuals due to ingestion of uranium and radon concentration in drinking water samples of four districts of Haryana, India

Science.gov (United States)

Panghal, Amanjeet; Kumar, Ajay; Kumar, Suneel; Singh, Joga; Sharma, Sumit; Singh, Parminder; Mehra, Rohit; Bajwa, B. S.

2017-06-01

Uranium gets into drinking water when the minerals containing uranium are dissolved in groundwater. Uranium and radon concentrations have been measured in drinking water samples from different water sources such as hand pumps, tube wells and bore wells at different depths from various locations of four districts (Jind, Rohtak, Panipat and Sonipat) of Haryana, India, using the LED flourimetry technique and RAD7, electronic silicon solid state detector. The uranium (238U) and radon (222Rn) concentrations in water samples have been found to vary from 1.07 to 40.25 µg L-1 with an average of 17.91 µg L-1 and 16.06 ± 0.97 to 57.35 ± 1.28 Bq L-1 with an average of 32.98 ± 2.45 Bq L-1, respectively. The observed value of radon concentration in 43 samples exceeded the recommended limits of 11 Bq L-1 (USEPA) and all the values are within the European Commission recommended limit of 100 Bq L-1. The average value of uranium concentration is observed to be within the safe limit recommended by World Health Organization (WHO) and Atomic Energy Regulatory Board. The annual effective dose has also been measured in all the water samples and is found to be below the prescribed dose limit of 100 µSv y-1 recommended by WHO. Risk assessment of uranium in water is also calculated using life time cancer risk, life time average daily dose and hazard quotient. The high uranium concentration observed in certain areas is due to interaction of ground water with the soil formation of this region and the local subsurface geology of the region.

Unphysiologically high magnesium concentrations support chondrocyte proliferation and redifferentiation.

Science.gov (United States)

Feyerabend, Frank; Witte, Frank; Kammal, Michael; Willumeit, Regine

2006-12-01

The effect of unphysiologically high extracellular magnesium concentrations on chondrocytes, induced by the supplementation of magnesium sulfate, was studied using a 3-phase tissue engineering model. The experiments showed that chondrocyte proliferation and redifferentiation, on the gene and protein expression level, are enhanced. A negative influence was found during chondrogenesis where an inhibition of extracellular matrix formation was observed. In addition, a direct impact on chondrocyte metabolism, elevated magnesium concentrations also affected growth factor effectiveness by consecutive influences during chondrogenesis. All observations were dosage dependent. The results of this study indicate that magnesium may be a useful tool for cartilage tissue engineering.

Less-studied TCE: are their environmental concentrations increasing due to their use in new technologies?

Science.gov (United States)

Filella, M; Rodríguez-Murillo, J C

2017-09-01

The possible environmental impact of the recent increase in use of a group of technology-critical elements (Nb, Ta, Ga, In, Ge and Te) is analysed by reviewing published concentration profiles in environmental archives (ice cores, ombrotrophic peat bogs, freshwater sediments and moss surveys) and evaluating temporal trends in surface waters. No increase has so far been recorded. The low potential direct emissions of these elements, resulting from their absolute low production levels, make it unlikely that the increasing use of these elements in modern technology has any noticeable effect on their environmental concentrations on a global scale. This holds particularly true for those of these elements that are probably emitted in relatively high amounts from other human activities (i.e., coal combustion and non-ferrous smelting), such as In, the most studied element of the group. Copyright © 2017 Elsevier Ltd. All rights reserved.

High serum uric acid concentration predicts poor survival in patients with breast cancer.

Science.gov (United States)

Yue, Cai-Feng; Feng, Pin-Ning; Yao, Zhen-Rong; Yu, Xue-Gao; Lin, Wen-Bin; Qian, Yuan-Min; Guo, Yun-Miao; Li, Lai-Sheng; Liu, Min

2017-10-01

Uric acid is a product of purine metabolism. Recently, uric acid has gained much attraction in cancer. In this study, we aim to investigate the clinicopathological and prognostic significance of serum uric acid concentration in breast cancer patients. A total of 443 female patients with histopathologically diagnosed breast cancer were included. After a mean follow-up time of 56months, survival was analysed using the Kaplan-Meier method. To further evaluate the prognostic significance of uric acid concentrations, univariate and multivariate Cox regression analyses were applied. Of the clinicopathological parameters, uric acid concentration was associated with age, body mass index, ER status and PR status. Univariate analysis identified that patients with increased uric acid concentration had a significantly inferior overall survival (HR 2.13, 95% CI 1.15-3.94, p=0.016). In multivariate analysis, we found that high uric acid concentration is an independent prognostic factor predicting death, but insufficient to predict local relapse or distant metastasis. Kaplan-Meier analysis indicated that high uric acid concentration is related to the poor overall survival (p=0.013). High uric acid concentration predicts poor survival in patients with breast cancer, and might serve as a potential marker for appropriate management of breast cancer patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Economic Justification of Concentrating Solar Power in High Renewable Energy Penetrated Power Systems

Energy Technology Data Exchange (ETDEWEB)

Hodge, Brian S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kroposki, Benjamin D [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Du, Ershun [Tsinghua University; Zhang, Ning [Tsinghua University; Kang, Chongqing [Tsinghua University; Xia, Qing [Tsinghua University

2018-04-24

Concentrating solar power (CSP) plants are able to provide both renewable energy and operational flexibility at the same time due to its thermal energy storage (TES). It is ideal generation to power systems lacking in flexibility to accommodate variable renewable energy (VRE) generation such as wind power and photovoltaics. However, its investment cost currently is too high to justify its benefit in terms of providing renewable energy only. In this paper we evaluate the economic benefit of CSP in high renewable energy penetrated power systems from two aspects: generating renewable energy and providing operational flexibility to help accommodating VRE. In order to keep the same renewable energy penetration level during evaluation, we compare the economic costs between the system with a high share of VRE and another in which some part of the VRE generation is replaced by CSP generation. The generation cost of a power system is analyzed through chronological operation simulation over a whole year. The benefit of CSP is quantified into two parts: (1) energy benefit - the saving investment of substituted VRE generation and (2) flexibility benefit - the reduction in operating cost due to substituting VRE with CSP. The break-even investment cost of CSP is further discussed. The methodology is tested on a modified IEEE RTS-79 system. The economic justifications of CSP are demonstrated in two practical provincial power systems with high penetration of renewable energy in northwestern China, Qinghai and Gansu, where the former province has massive inflexible thermal power plants but later one has high share of flexible hydro power. The results suggest that the CSP is more beneficial in Gansu system than in Qinghai. The levelized benefit of CSP, including both energy benefit and flexibility benefit, is about 0.177-0.191 $/kWh in Qinghai and about 0.238-0.300 $/kWh in Gansu, when replacing 5-20% VRE generation with CSP generation.

Niacin alters the ruminal microbial composition of cattle under high-concentrate condition

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Dan Luo

2017-06-01

Full Text Available To understand the effects of niacin on the ruminal microbial ecology of cattle under high-concentrate diet condition, Illumina MiSeq sequencing technology was used. Three cattle with rumen cannula were used in a 3 × 3 Latin-square design trial. Three diets were fed to these cattle during 3 periods for 3 days, respectively: high-forage diet (HF; forage-to-concentrate ratio = 80:20, high-concentrate diet (HC; forage-to-concentrate ratio = 20:80, and HC supplemented with 800 mg/kg niacin (HCN. Ruminal pH was measured before feeding and every 2 h after initiating feeding. Ruminal fluid was sampled at the end of each period for microbial DNA extraction. Overall, our findings revealed that subacute ruminal acidosis (SARA was induced and the α-diversity of ruminal bacterial community decreased in the cattle of HC group. Adding niacin in HC could relieve the symptoms of SARA in the cattle but the ruminal pH value and the Shannon index of ruminal bacterial community of HCN group were still lower than those of HF group. Whatever the diet was, the ruminal bacterial community of cattle was dominated by Bacteroidetes, Firmicutes and Proteobacteria. High-concentrate diet significantly increased the abundance of Prevotella, and decreased the abundance of Paraprevotella, Sporobacter, Ruminococcus and Treponema than HF. Compared with HC, HCN had a trend to decrease the percentage of Prevotella, and to increase the abundance of Succiniclasticum, Acetivibrio and Treponema. Increasing concentrate ratio could decrease ruminal pH value, and change the ruminal microbial composition. Adding niacin in HC could increase the ruminal pH value, alter the ruminal microbial composition.

The virucidal spectrum of a high concentration alcohol mixture

NARCIS (Netherlands)

van Engelenburg, F. A. C.; Terpstra, F. G.; Schuitemaker, H.; Moorer, W. R.

2002-01-01

The virucidal spectrum of a high concentration alcohol mixture (80% ethanol and 5% isopropanol) was determined for a broad series of lipid-enveloped (LE) and non-lipid-enveloped (NLE) viruses covering all relevant blood-borne viruses. LE viruses were represented by human immunodeficiency virus

Highly Localized Acoustic Streaming and Size-Selective Submicrometer Particle Concentration Using High Frequency Microscale Focused Acoustic Fields.

Science.gov (United States)

Collins, David J; Ma, Zhichao; Ai, Ye

2016-05-17

Concentration and separation of particles and biological specimens are fundamental functions of micro/nanofluidic systems. Acoustic streaming is an effective and biocompatible way to create rapid microscale fluid motion and induce particle capture, though the >100 MHz frequencies required to directly generate acoustic body forces on the microscale have traditionally been difficult to generate and localize in a way that is amenable to efficient generation of streaming. Moreover, acoustic, hydrodynamic, and electrical forces as typically applied have difficulty manipulating specimens in the submicrometer regime. In this work, we introduce highly focused traveling surface acoustic waves (SAW) at high frequencies between 193 and 636 MHz for efficient and highly localized production of acoustic streaming vortices on microfluidic length scales. Concentration occurs via a novel mechanism, whereby the combined acoustic radiation and streaming field results in size-selective aggregation in fluid streamlines in the vicinity of a high-amplitude acoustic beam, as opposed to previous acoustic radiation induced particle concentration where objects typically migrate toward minimum pressure locations. Though the acoustic streaming is induced by a traveling wave, we are able to manipulate particles an order of magnitude smaller than possible using the traveling wave force alone. We experimentally and theoretically examine the range of particle sizes that can be captured in fluid streamlines using this technique, with rapid particle concentration demonstrated down to 300 nm diameters. We also demonstrate that locations of trapping and concentration are size-dependent, which is attributed to the combined effects of the acoustic streaming and acoustic forces.

A selective electrocatalyst-based direct methanol fuel cell operated at high concentrations of methanol.

Science.gov (United States)

Feng, Yan; Liu, Hui; Yang, Jun

2017-06-01

Owing to the serious crossover of methanol from the anode to the cathode through the polymer electrolyte membrane, direct methanol fuel cells (DMFCs) usually use dilute methanol solutions as fuel. However, the use of high-concentration methanol is highly demanded to improve the energy density of a DMFC system. Instead of the conventional strategies (for example, improving the fuel-feed system, membrane development, modification of electrode, and water management), we demonstrate the use of selective electrocatalysts to run a DMFC at high concentrations of methanol. In particular, at an operating temperature of 80°C, the as-fabricated DMFC with core-shell-shell Au@Ag 2 S@Pt nanocomposites at the anode and core-shell Au@Pd nanoparticles at the cathode produces a maximum power density of 89.7 mW cm -2 at a methanol feed concentration of 10 M and maintains good performance at a methanol concentration of up to 15 M. The high selectivity of the electrocatalysts achieved through structural construction accounts for the successful operation of the DMFC at high concentrations of methanol.

A selective electrocatalyst–based direct methanol fuel cell operated at high concentrations of methanol

Science.gov (United States)

Feng, Yan; Liu, Hui; Yang, Jun

2017-01-01

Owing to the serious crossover of methanol from the anode to the cathode through the polymer electrolyte membrane, direct methanol fuel cells (DMFCs) usually use dilute methanol solutions as fuel. However, the use of high-concentration methanol is highly demanded to improve the energy density of a DMFC system. Instead of the conventional strategies (for example, improving the fuel-feed system, membrane development, modification of electrode, and water management), we demonstrate the use of selective electrocatalysts to run a DMFC at high concentrations of methanol. In particular, at an operating temperature of 80°C, the as-fabricated DMFC with core-shell-shell Au@Ag2S@Pt nanocomposites at the anode and core-shell Au@Pd nanoparticles at the cathode produces a maximum power density of 89.7 mW cm−2 at a methanol feed concentration of 10 M and maintains good performance at a methanol concentration of up to 15 M. The high selectivity of the electrocatalysts achieved through structural construction accounts for the successful operation of the DMFC at high concentrations of methanol. PMID:28695199

Performance of planar heterojunction perovskite solar cells under light concentration

Directory of Open Access Journals (Sweden)

Aaesha Alnuaimi

2016-11-01

Full Text Available In this work, we present 2D simulation of planar heterojunction perovskite solar cells under high concentration using physics-based TCAD. The performance of planar perovskite heterojunction solar cells is examined up to 1000 suns. We analyze the effect of HTM mobility and band structure, surface recombination velocities at interfaces and the effect of series resistance under concentrated light. The simulation results revealed that the low mobility of HTM material limits the improvement in power conversation efficiency of perovskite solar cells under concentration. In addition, large band offset at perovskite/HTM interface contributes to the high series resistance. Moreover, losses due to high surface recombination at interfaces and the high series resistance deteriorate significantly the performance of perovskite solar cells under concentration.

Effects of high concentration of chromium stress on physiological ...

African Journals Online (AJOL)

We studied the effects of high concentration of chromium (Cr) stress on physiological and biochemical characters and accumulation of Cr in Pingyang Tezao tea [Camellia sinensis (L) O. Kutze 'Pingyangtezao'] through a pot experiment. The results show that the indicators of photosynthesis were all suppressed with ...

Concentration Polarization in Translocation of DNA through Nanopores and Nanochannels

NARCIS (Netherlands)

Das, S.; Dubsky, P.; van den Berg, Albert; Eijkel, Jan C.T.

2012-01-01

In this Letter we provide a theory to show that high-field electrokinetic translocation of DNA through nanopores or nanochannels causes large transient variations of the ionic concentrations in front and at the back of the DNA due to concentration polarization (CP). The CP causes strong local

Exposure due to radon in homes - an IAEA perspective

International Nuclear Information System (INIS)

Navratilova-Rovenska, K.; Boal, T.; Colgan, T.

2014-01-01

The results of miner and residential epidemiology studies provide statistically strong evidence of harmful effects of exposure due to radon and its progeny. With the publication of the fifth edition of the International Basic Safety Standards, of the World Health Organizations Handbook on Indoor Radon and new ICRP statement on radon, there is increased interest from the public health and radiation protection authorities on controlling exposure due to radon and its progeny.The IAEA Safety Requirements publication 'Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards' sets out requirements on governments for control of existing exposure situations, which includes exposure due to radon. The types of situation that are included in the scope of existing exposure situations include exposure in workplaces for which the exposure due to radon is not required by or directly related to the work and for which annual average activity concentrations due to 222 Rn must not exceed a maximum reference level of 1000 Bq/m 3 annual activity concentration, as well as exposure in dwellings and in other buildings with high occupancy factors for members of the public for which the reference level must not exceed a maximum value of 300 Bq/m 3 . These requirements include: collecting data on the activity concentrations of radon in dwellings and other buildings with high occupancy by the public; providing information on exposure due to radon and the associated health risks; and if necessary, to develop an action plan for controlling public exposure to radon. The IAEA has developed a Safety Guide to provide guidance on developing the radon action plan: 'Protection of the Public against Exposure Indoors due to Radon and Other Natural Sources of Radiation'. This presentation will summarize the information on the assistance that the IAEA is currently providing to IAEA Member States to develop radon action plans. These activities include

Changing climate and nutrient transfers: Evidence from high temporal resolution concentration-flow dynamics in headwater catchments.

Science.gov (United States)

Ockenden, M C; Deasy, C E; Benskin, C McW H; Beven, K J; Burke, S; Collins, A L; Evans, R; Falloon, P D; Forber, K J; Hiscock, K M; Hollaway, M J; Kahana, R; Macleod, C J A; Reaney, S M; Snell, M A; Villamizar, M L; Wearing, C; Withers, P J A; Zhou, J G; Haygarth, P M

2016-04-01

We hypothesise that climate change, together with intensive agricultural systems, will increase the transfer of pollutants from land to water and impact on stream health. This study builds, for the first time, an integrated assessment of nutrient transfers, bringing together a) high-frequency data from the outlets of two surface water-dominated, headwater (~10km(2)) agricultural catchments, b) event-by-event analysis of nutrient transfers, c) concentration duration curves for comparison with EU Water Framework Directive water quality targets, d) event analysis of location-specific, sub-daily rainfall projections (UKCP, 2009), and e) a linear model relating storm rainfall to phosphorus load. These components, in combination, bring innovation and new insight into the estimation of future phosphorus transfers, which was not available from individual components. The data demonstrated two features of particular concern for climate change impacts. Firstly, the bulk of the suspended sediment and total phosphorus (TP) load (greater than 90% and 80% respectively) was transferred during the highest discharge events. The linear model of rainfall-driven TP transfers estimated that, with the projected increase in winter rainfall (+8% to +17% in the catchments by 2050s), annual event loads might increase by around 9% on average, if agricultural practices remain unchanged. Secondly, events following dry periods of several weeks, particularly in summer, were responsible for high concentrations of phosphorus, but relatively low loads. The high concentrations, associated with low flow, could become more frequent or last longer in the future, with a corresponding increase in the length of time that threshold concentrations (e.g. for water quality status) are exceeded. The results suggest that in order to build resilience in stream health and help mitigate potential increases in diffuse agricultural water pollution due to climate change, land management practices should target

Investigating high-concentration monoclonal antibody powder suspension in nonaqueous suspension vehicles for subcutaneous injection.

Science.gov (United States)

Bowen, Mayumi; Armstrong, Nick; Maa, Yuh-Fun

2012-12-01

Developing high-concentration monoclonal antibody (mAb) liquid formulations for subcutaneous (s.c.) administration is challenging because increased viscosity makes injection difficult. To overcome this obstacle, we investigated a nonaqueous powder suspension approach. Three IgG1 mAbs were spray dried and suspended at different concentrations in Miglyol® 840, benzyl benzoate, or ethyl lactate. Suspensions were characterized for viscosity, particle size, and syringeability; physical stability was visually inspected. Suspensions generally outperformed liquid solutions for injectability despite higher viscosity at the same mAb concentrations. Powder formulations and properties had little effect on viscosity or injectability. Ethyl lactate suspensions had lowest viscosity (Miglyol® 840 improved overall performance in high mAb concentration suspensions. This study demonstrated the viability of high mAb concentration (>300 mg/mL) in suspension formulations for s.c. administration. Copyright © 2012 Wiley Periodicals, Inc.

Storage in high-barrier pouches increases the sulforaphane concentration in broccoli florets.

Directory of Open Access Journals (Sweden)

Yoshio Makino

Full Text Available Sulforaphane is a phytochemical that is usually found in cruciferous vegetables and is known to have a depressive effect on gastric cancer. Preliminary investigations showed that the sulforaphane concentration in broccoli (Brassica oleracea var. italica florets increased under anoxia. Therefore, in the present study, we examined the effect of different atmospheric conditions on the sulforaphane concentration in broccoli and also tested whether there are concurrent effects on the concentration of ethanol, which is an unfavorable byproduct of fermentation. The sulforaphane concentration in broccoli florets was significantly elevated by 1.9- to 2.8-fold after 2 d of storage under hypoxia at ca. 0% O2 and ca. 24% CO2 at 20°C, whereas no such increase was observed following storage under normoxia at ca. 0% O2 without CO2 at 20°C. Furthermore, after 2 d, the sulforaphane concentration under hypoxia was 1.6- to 2.3-fold higher than that under normoxia. These results suggest that storage under hypoxia with high CO2 levels can elevate the sulforaphane concentration in broccoli florets. However, the elevated sulforaphane concentration could not be maintained beyond 2 d. There was no significant difference in the concentration of ethanol between florets that were stored under hypoxia with/without CO2 or normoxia at 2 d. However, the ethanol concentrations inside the pouches significantly increased between 2 d and 7 d. These findings indicate that the quality of broccoli florets can be improved through storage under hypoxia with high CO2 levels at 20°C for 2 d.

Storage in high-barrier pouches increases the sulforaphane concentration in broccoli florets.

Science.gov (United States)

Makino, Yoshio; Nishimura, Yuto; Oshita, Seiichi; Mizosoe, Takaharu; Akihiro, Takashi

2018-01-01

Sulforaphane is a phytochemical that is usually found in cruciferous vegetables and is known to have a depressive effect on gastric cancer. Preliminary investigations showed that the sulforaphane concentration in broccoli (Brassica oleracea var. italica) florets increased under anoxia. Therefore, in the present study, we examined the effect of different atmospheric conditions on the sulforaphane concentration in broccoli and also tested whether there are concurrent effects on the concentration of ethanol, which is an unfavorable byproduct of fermentation. The sulforaphane concentration in broccoli florets was significantly elevated by 1.9- to 2.8-fold after 2 d of storage under hypoxia at ca. 0% O2 and ca. 24% CO2 at 20°C, whereas no such increase was observed following storage under normoxia at ca. 0% O2 without CO2 at 20°C. Furthermore, after 2 d, the sulforaphane concentration under hypoxia was 1.6- to 2.3-fold higher than that under normoxia. These results suggest that storage under hypoxia with high CO2 levels can elevate the sulforaphane concentration in broccoli florets. However, the elevated sulforaphane concentration could not be maintained beyond 2 d. There was no significant difference in the concentration of ethanol between florets that were stored under hypoxia with/without CO2 or normoxia at 2 d. However, the ethanol concentrations inside the pouches significantly increased between 2 d and 7 d. These findings indicate that the quality of broccoli florets can be improved through storage under hypoxia with high CO2 levels at 20°C for 2 d.

Plasma PCSK9 concentrations during an oral fat load and after short term high-fat, high-fat high-protein and high-fructose diets

Directory of Open Access Journals (Sweden)

Cariou Bertrand

2013-01-01

Full Text Available Abstract Background PCSK9 (Proprotein Convertase Subtilisin Kexin type 9 is a circulating protein that promotes hypercholesterolemia by decreasing hepatic LDL receptor protein. Under non interventional conditions, its expression is driven by sterol response element binding protein 2 (SREBP2 and follows a diurnal rhythm synchronous with cholesterol synthesis. Plasma PCSK9 is associated to LDL-C and to a lesser extent plasma triglycerides and insulin resistance. We aimed to verify the effect on plasma PCSK9 concentrations of dietary interventions that affect these parameters. Methods We performed nutritional interventions in young healthy male volunteers and offspring of type 2 diabetic (OffT2D patients that are more prone to develop insulin resistance, including: i acute post-prandial hyperlipidemic challenge (n=10, ii 4 days of high-fat (HF or high-fat/high-protein (HFHP (n=10, iii 7 (HFruc1, n=16 or 6 (HFruc2, n=9 days of hypercaloric high-fructose diets. An acute oral fat load was also performed in two patients bearing the R104C-V114A loss-of-function (LOF PCSK9 mutation. Plasma PCSK9 concentrations were measured by ELISA. For the HFruc1 study, intrahepatocellular (IHCL and intramyocellular lipids were measured by 1H magnetic resonance spectroscopy. Hepatic and whole-body insulin sensitivity was assessed with a two-step hyperinsulinemic-euglycemic clamp (0.3 and 1.0 mU.kg-1.min-1. Findings HF and HFHP short-term diets, as well as an acute hyperlipidemic oral load, did not significantly change PCSK9 concentrations. In addition, post-prandial plasma triglyceride excursion was not altered in two carriers of PCSK9 LOF mutation compared with non carriers. In contrast, hypercaloric 7-day HFruc1 diet increased plasma PCSK9 concentrations by 28% (p=0.05 in healthy volunteers and by 34% (p=0.001 in OffT2D patients. In another independent study, 6-day HFruc2 diet increased plasma PCSK9 levels by 93% (p Conclusions Plasma PCSK9 concentrations vary

A study on hydrogen burn due to the operation of containment spray system

International Nuclear Information System (INIS)

Park, S.Y.; Kim, D.H.; Jin, Y.; Park, C.K.

1995-01-01

The bounding calculation for inflammable gas combustion due to the steam condensation by the operation of the containment spray system was performed. Sensitivity study was performed for two initiating events, station blackout and loss of coolant accident. The parameters for sensitivity study are the condition of cavity, wet or dry, and the timing of operation of the containment spray system. It is shown, based on MAAP4 analyses, that: for dry cavity, auto-ignition burn and hydrogen laden jet burn due to the high temperature in the reactor cavity consumes large amount of burnable gas in the containment and reduces the peak pressure at the global burn by flammability criteria; for wet cavity, large amount of hydrogen and carbon monoxide are generated after dryout of the reactor cavity, but burn is prohibited due to the low gas temperature in the high concentration of the steam. The late operation of the containment spray system condenses the steam rapidly, which results in the global burn at high concentration of burnable gas in the containment. The containment peak pressure from this burn is determined to be high enough to threaten the containment integrity significantly. (author). 3 refs., 3 tabs

Hydrogen-bonded structure in highly concentrated aqueous LiBr solutions

International Nuclear Information System (INIS)

Imano, Masahiro; Kameda, Yasuo; Usuki, Takeshi; Uemura, Osamu

2001-01-01

Neutron diffraction measurements were carried out for H/D isotopically substituted aqueous 10, 25 and 33 mol% LiBr solutions in order to obtain structural information on the intermolecular hydrogen bonds among water molecules in highly concentrated aqueous solutions. Observed scattering cross sections for D 2 O (99.9 % D), 0 H 2 O(35.9 % D) and 0-2 H 2 O(68.0 % D) solutions were combined to deduce partial structure factors, a HH (Q), a XH (Q) and a XX (Q) (X: O, Br and Li). The least squares fitting analysis was applied to the observed partial structure factors to determine the nearest neighbor interatomic distance, root-mean-square amplitude and coordination number. Intermolecular distances, r OH =1.91(1) A, r HH =2.38(1) A and r OO =3.02(1) A, between the nearest neighbor water molecules, were obtained for the 10 mol% LiBr solution. On the other hand, the intermolecular O···H interaction was found to almost disappear in concentrated 25 and 33 mol% LiBr solutions. The result implies that the hydrogen-bonded network is completely broken in highly concentrated aqueous LiBr solutions. (author)

The protective role of low-concentration alcohol in high-fructose induced adverse cardiovascular events in mice.

Science.gov (United States)

Wu, Xiaoqi; Pan, Bo; Wang, Ying; Liu, Lingjuan; Huang, Xupei; Tian, Jie

2018-01-01

Cardiovascular disease remains a worldwide public health issue. As fructose consumption is dramatically increasing, it has been demonstrated that a fructose-rich intake would increase the risk of cardiovascular disease. In addition, emerging evidences suggest that low concentration alcohol intake may exert a protective effect on cardiovascular system. This study aimed to investigate whether low-concentration alcohol consumption would prevent the adverse effects on cardiovascular events induced by high fructose in mice. From the results of hematoxylin-eosin staining, echocardiography, heart weight/body weight ratio and the expression of hypertrophic marker ANP, we found high-fructose result in myocardial hypertrophy and the low-concentration alcohol consumption would prevent the cardiomyocyte hypertrophy from happening. In addition, we observed low-concentration alcohol consumption could inhibit mitochondria swollen induced by high-fructose. The elevated levels of glucose, triglyceride, total cholesterol in high-fructose group were reduced by low concentration alcohol. Low expression levels of SIRT1 and PPAR-γ induced by high-fructose were significantly elevated when fed with low-concentration alcohol. The histone lysine 9 acetylation (acH3K9) level was decreased in PPAR-γ promoter in high-fructose group but elevated when intake with low concentration alcohol. The binding levels of histone deacetylase SIRT1 were increased in the same region in high-fructose group, while the low concentration alcohol can prevent the increased binding levels. Overall, our study indicates that low-concentration alcohol consumption could inhibit high-fructose related myocardial hypertrophy, cardiac mitochondria damaged and disorders of glucose-lipid metabolism. Furthermore, these findings also provide new insights into histone acetylation-deacetylation mechanisms of low-concentration alcohol treatment that may contribute to the prevention of cardiovascular disease induced by high

Fabrication procedures for manufacturing high uranium concentration dispersion fuel elements

International Nuclear Information System (INIS)

Souza, J.A.B.; Durazzo, M.

2010-01-01

IPEN developed and made available for routine production the technology for manufacturing dispersion type fuel elements for use in research reactors. However, the fuel produced at IPEN is limited to the uranium concentration of 3.0 gU/cm 3 by using the U 3 Si 2 -Al dispersion. Increasing the uranium concentration of the fuel is interesting by the possibility of increasing the reactor core reactivity and lifetime of the fuel. It is possible to increase the concentration of uranium in the fuel up to the technological limit of 4.8 gU/cm 3 for the U 3 Si 2 -Al dispersion, which is well placed around the world. This new fuel will be applicable in the new Brazilian-Multipurpose Reactor RMB. This study aimed to develop the manufacturing process of high uranium concentration fuel, redefining the procedures currently used in the manufacture of IPEN. This paper describes the main procedures adjustments that will be necessary. (author)

Fabrication procedures for manufacturing high uranium concentration dispersion fuel elements

Energy Technology Data Exchange (ETDEWEB)

Souza, Jose Antonio Batista de; Durazzo, Michelangelo, E-mail: jasouza@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-07-01

IPEN developed and made available for routine production the technology for manufacturing dispersion type fuel elements for use in research reactors. However, the fuel produced at IPEN is limited to the uranium concentration of 3.0 g U/c m3 by using the U{sub 3}Si{sub 2}-Al dispersion. Increasing the uranium concentration of the fuel is interesting by the possibility of increasing the reactor core reactivity and lifetime of the fuel. It is possible to increase the concentration of uranium in the fuel up to the technological limit of 4.8 g U/c m3 for the U{sub 3}Si{sub 2}-Al dispersion, which is well placed around the world. This new fuel will be applicable in the new Brazilian- Multipurpose Reactor RMB. This study aimed to develop the manufacturing process of high uranium concentration fuel, redefining the procedures currently used in the manufacture of IPEN. This paper describes the main procedures adjustments that will be necessary. (author)

Higs-instrument: design and demonstration of a high performance gas concentration imager

Science.gov (United States)

Verlaan, A. L.; Klop, W. A.; Visser, H.; van Brug, H.; Human, J.

2017-09-01

Climate change and environmental conditions are high on the political agenda of international governments. Laws and regulations are being setup all around the world to improve the air quality and to reduce the impact. The growth of a number of trace gasses, including CO2, Methane and NOx are especially interesting due to their environmental impact. The regulations made are being based on both models and measurements of the trend of those trace gases over the years. Now the regulations are in place also enforcement and therewith measurements become more and more important. Instruments enabling high spectral and spatial resolution as well as high accurate measurements of trace gases are required to deliver the necessary inputs. Nowadays those measurements are usually performed by space based spectrometers. The requirement for high spectral resolution and measurement accuracy significantly increases the size of the instruments. As a result the instrument and satellite becomes very expensive to develop and to launch. Specialized instruments with a small volume and the required performance will offer significant advantages in both cost and performance. Huib's Innovative Gas Sensor (HIGS, named after its inventor Huib Visser), currently being developed at TNO is an instrument that achieves exactly that. Designed to measure only a single gas concentration, opposed to deriving it from a spectrum, it achieves high performance within a small design volume. The instrument enables instantaneous imaging of the gas distribution of the selected gas. An instrument demonstrator has been developed for NO2 detection. Laboratory measurements proved the measurement technique to be successful. An on-sky measurement campaign is in preparation. This paper addresses both the instrument design as well as the demonstrated performances.

Nitrate concentrations in soil solutions below Danish forests

DEFF Research Database (Denmark)

Callesen, Ingeborg; Raulund-Rasmussen, Karsten; Gundersen, Per

1999-01-01

leaching in relation to land-use, a national monitoring programme has established sampling routines in a 7x7 km grid including 111 points in forests. During winters of 1986-1993, soil samples were obtained from a depth of 0-25, 25-50, 50-75 and 75-100 cm. Nitrate concentrations in soil solutions were...... species. A few sites deviated radically from the general pattern of low concentrations. The elevated concentrations recorded there were probably caused by high levels of N deposition due to emission from local sources or temporal disruptions of the N cycle. The nitrate concentration in the soil solution...

Spectral and Concentration Sensitivity of Multijunction Solar Cells at High Temperature: Preprint

Energy Technology Data Exchange (ETDEWEB)

Friedman, Daniel J.; Steiner, Myles A.; Perl, Emmett E.; Simon, John

2017-06-14

We model the performance of two-junction solar cells at very high temperatures of ~400 degrees C and beyond for applications such as hybrid PV/solar-thermal power production, and identify areas in which the design and performance characteristics behave significantly differently than at more conventional near-room-temperature operating conditions. We show that high-temperature operation reduces the sensitivity of the cell efficiency to spectral content, but increases the sensitivity to concentration, both of which have implications for energy yield in terrestrial PV applications. For other high-temperature applications such as near-sun space missions, our findings indicate that concentration may be a useful tool to enhance cell efficiency.

Concentration profiles near an activated enzyme.

Science.gov (United States)

Park, Soohyung; Agmon, Noam

2008-09-25

When a resting enzyme is activated, substrate concentration profile evolves in its vicinity, ultimately tending to steady state. We use modern theories for many-body effects on diffusion-influenced reactions to derive approximate analytical expressions for the steady-state profile and the Laplace transform of the transient concentration profiles. These show excellent agreement with accurate many-particle Brownian-dynamics simulations for the Michaelis-Menten kinetics. The steady-state profile has a hyperbolic dependence on the distance of the substrate from the enzyme, albeit with a prefactor containing the complexity of the many-body effects. These are most conspicuous for the substrate concentration at the surface of the enzyme. It shows an interesting transition as a function of the enzyme turnover rate. When it is high, the contact concentration decays monotonically to steady state. However, for slow turnover it is nonmonotonic, showing a minimum due to reversible substrate binding, then a maximum due to diffusion of new substrate toward the enzyme, and finally decay to steady state. Under certain conditions one can obtain a good estimate for the critical value of the turnover rate constant at the transition.

Concentration dependent hydrogen diffusion in tungsten

Energy Technology Data Exchange (ETDEWEB)

Ahlgren, T., E-mail: tommy.ahlgren@helsinki.fi; Bukonte, L.

2016-10-15

The diffusion of hydrogen in tungsten is studied as a function of temperature, hydrogen concentration and pressure using Molecular Dynamics technique. A new analysis method to determine diffusion coefficients that accounts for the random oscillation of atoms around the equilibrium position is presented. The results indicate that the hydrogen migration barrier of 0.25 eV should be used instead of the presently recommended value of 0.39 eV. This conclusion is supported by both experiments and density functional theory calculations. Moreover, the migration volume at the saddle point for H in W is found to be positive: ΔV{sub m} ≈ 0.488 Å{sup 3}, leading to a decrease in the diffusivity at high pressures. At high H concentrations, a dramatic reduction in the diffusion coefficient is observed, due to site blocking and the repulsive H-H interaction. The results of this study indicates that high flux hydrogen irradiation leads to much higher H concentrations in tungsten than expected. - Highlights: • The recommended value of 0.39 eV for the H in W migration barrier should be changed to 0.25 eV. • The random oscillation of atoms around the equilibrium position can be dealt with in diffusion simulations. • Hydrogen diffusion in tungsten is highly concentration dependent.

Influence of vibration on structure rheological properties of a highly concentrated suspension

Science.gov (United States)

Ouriev Uriev, Boris N.; Uriev, Naum B.

2005-08-01

The influence of mechanical vibration on the flow properties of a highly concentrated multiphase food system is explored in this work. An experimental set-up was designed and adapted to a conventional rotational rheometer with precise rheological characterization capability. A number of calibration tests were performed prior to fundamental experiments with a highly concentrated chocolate suspension. Also, the prediction of wall slippage in shear flow under vibration was evaluated. Analysis of the boundary conditions shows that no side effects such as wall slippage or the Taylor effect were present during the shear experiment under vibration. It was found that superposition of mechanical vibration and shear flow radically decreases the shear viscosity. Comparison between reference shear viscosities at specified shear rates and those measured under vibration shows considerable differences in flow properties. Conversion of the behaviour of the concentrated suspension from strongly shear-thinning to Newtonian flow is reported. Also, the appearance of vibration-induced dilatancy as a new phenomenon is described. It is suggested to relate such phenomena to the non-equilibrium between structure formation and disintegration under vibration and hydrodynamic forces of shear flow. The influence of vibration on structure formation can be well observed during measurement of the yield value of the chocolate suspension under vibration. Comparison with reference data shows how sensitive the structure of the concentrated suspension is to vibration in general. The effects and observations revealed provide a solid basis for further fundamental investigations of structure formation regularities in the flow of any highly concentrated system. The results also show the technological potential for non-conventional treatment of concentrated, multiphase systems.

Risk of a false decision on conformity of an environmental compartment due to measurement uncertainty of concentrations of two or more pollutants.

Science.gov (United States)

Pennecchi, Francesca R; Kuselman, Ilya; da Silva, Ricardo J N B; Hibbert, D Brynn

2018-07-01

Risks of false decisions in conformity assessment of an environmental compartment due to measurement uncertainty of concentrations of two or more pollutants are discussed. Even if the assessment of conformity for each pollutant in the compartment is successful, the total probability of a false decision concerning the compartment as a whole might still be significant. A model of the total probability of a false decision, formulated on the base of the law of total probability, is used, for example, for a study of test results of total suspended particulate matter (TSPM) concentration in ambient air near to three independent stone quarries located in Israel, as the sources of the air pollution. Total probabilities of underestimation of TSPM concentration (total risk of the inhabitants) and overestimation (total risk of the stone producers) are evaluated as a combination of the particular risks of air conformity assessment concerning TSPM concentration for each quarry. These probabilities characterize conformity of the TSPM concentration in the region of the quarries as a whole. Core code developed in R programming environment for the calculations is provided. Copyright © 2018 Elsevier Ltd. All rights reserved.

Use of MICRAS code on the evaluation of the maximum radionuclides concentrations due to transport/migration of decay chain in groundwaters

International Nuclear Information System (INIS)

Aquino Branco, O.E. de

1995-01-01

This paper presents a methodology for the evaluation of the maximum radionuclides concentrations in groundwaters, due to the transport/migration of decay chains. Analytical solution of the equations system is difficult, even if only three elements of the decay chain are considered. Therefore, a numerical solution is most convenient. An application of the MICRAS code, developed to assess maximum concentrations of each radionuclide, starting with the initial concentrations, is presented. The maximum concentration profile for 226 Ra, calculated using MICRAS, is compared with the results obtained through an analytical and a numerical model. The fitness of results is considered good. Simplified models, like the one represented by the application of MICRAS, are largely employed in the section in the selection and characterization of sites for radioactive wastes repositories and in studies of safety evaluation for the same purpose. A detailed analysis of the transport/migration of contaminants in aquifers requires a large quantify of data from the site and from the installation as well, which makes this analysis expensive and inviable during the preliminary phases of the studies. (author). 6 refs, 1 fig, 1 tab

The preparation and ethanol fermentation of high-concentration sugars from steam-explosion corn stover.

Science.gov (United States)

Xie, Hui; Wang, Fengqin; Yin, Shuangyao; Ren, Tianbao; Song, Andong

2015-05-01

In the field of biofuel ethanol, high-concentration- reducing sugars made from cellulosic materials lay the foundation for high-concentration ethanol fermentation. In this study, corn stover was pre-treated in a process combining chemical methods and steam explosion; the cellulosic hydrolyzed sugars obtained by fed-batch saccharification were then used as the carbon source for high-concentration ethanol fermentation. Saccharomyces cerevisiae 1308, Angel yeast, and Issatchenkia orientalis were shake-cultured with Pachysolen tannophilus P-01 for fermentation. Results implied that the ethanol yields from the three types of mixed strains were 4.85 g/100 mL, 4.57 g/100 mL, and 5.02 g/100 mL (separately) at yield rates of 91.6, 89.3, and 92.2%, respectively. Therefore, it was inferred that shock-fermentation using mixed strains achieved a higher ethanol yield at a greater rate in a shorter fermentation period. This study provided a theoretical basis and technical guidance for the fermentation of industrial high-concentrated cellulosic ethanol.

Innovative encapsulated oxygen-releasing beads for bioremediation of BTEX at high concentration in groundwater.

Science.gov (United States)

Lin, Chi-Wen; Wu, Chih-Hung; Guo, Pei-Yu; Chang, Shih-Hsien

2017-12-15

Both a low concentration of dissolved oxygen and the toxicity of a high concentration of BTEX inhibit the bioremediation of BTEX in groundwater. A novel method of preparing encapsulated oxygen-releasing beads (encap-ORBs) for the biodegradation of BTEX in groundwater was developed. Experimental results show that the integrality and oxygen-releasing capacity of encap-ORBs exceeded those of ORBs. The use of polyvinyl alcohol (PVA) with high M.W. to prepare encap-ORBs improved their integrality. The encap-ORBs effectively released oxygen for 128 days. High concentration of BTEX (480 mg L -1 ) inhibited the biodegradation by the free cells. Immobilization of degraders in the encap-ORB alleviated the inhibition. Scanning electron microscope analysis reveals that the BTEX degraders grew on the surface of encap-ORB after bioremediation. The above results indicate that the encap-ORBs were effective in the bioremediation of BTEX at high concentration in groundwater. Copyright © 2017 Elsevier Ltd. All rights reserved.

Atmospheric concentration of 210Pb in East Asia

International Nuclear Information System (INIS)

Doi, T.; Sato, S.; Sato, J.

2003-01-01

Concentrations of 210 Pb and 7 Be in the surface air were measured at Tsukuba, Japan. The air concentrations of 210 Pb and 7 Be ranged from 0.2 to 0.7 mBq/m 3 and from 1 to 6 mBq/m 3 , respectively. Seasonal variation of 210 Pb concentration was similar to that of 7 Be, showing a 'two-peak' variation pattern: high concentrations appeared in spring and fall. Atmospheric concentrations of 210 Pb and their variations over Urumqi, Lanzhou and Baotou, cities located inland area of the Eurasian Continent, were observed. The monthly average concentrations ranged from 0.27 to 4.57 mBq/m 3 . The concentrations over these cities in winter were several times higher than that observed at Tsukuba, and the range of variation was also larger. The variations in concentration over the 3 localities resembled well with each other, showing the similar seasonal variation pattern: low concentration appeared in summer and high in winter. This variation pattern was different from that observed at Tsukuba. The variations in concentration over the Eurasian Continent, where precipitation is extremely smaller than that of Japan, inversely correlated quite well with the variation in the precipitation. The atmospheric concentrations of 210 Pb ranged from 0.9 to 4.6 mBq/m 3 at Beijing and from 1.4 to 7.8 mBq/m 3 at Chengdu and from 0.5 to 4.9 mBq/m 3 at Seoul, respectively, which were in the similar level to those observed previously in the inland area of the Eurasian Continent. Seasonal variations of the 210 Pb concentration showed the 'one-peak' variation pattern: the maximum levels were recorded in winter season. Small additional rises in the atmospheric 210 Pb concentrations observed in the period from spring to fall seasons may be due to complicated meteorology with high pressure systems at Beijing and Seoul and due to the topographical situation at Chengdu. Long range transport from the Eurasian Continent to the Japanese Islands was also assessed. The air mass from continent reached the

Beryllium-10 concentrations in water samples of high northern latitudes

Energy Technology Data Exchange (ETDEWEB)

Strobl, C.; Eisenhauer, A.; Schulz, V.; Baumann, S.; Mangini, A. [Heidelberger Akademie der Wissenschaften, Heildelberg (Germany); Kubik, P.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1997-09-01

{sup 10}Be concentrations in the water column of high northern latitudes were not available so far. We present different {sup 10}Be profiles from the Norwegian-Greenland Sea, the Arctic Ocean, and the Laptev Sea. (author) 3 fig., 3 refs.

Higher concentrations of nanoscale zero-valent iron (nZVI) in soil induced rice chlorosis due to inhibited active iron transportation

International Nuclear Information System (INIS)

Wang, Jie; Fang, Zhanqiang; Cheng, Wen; Yan, Xiaomin; Tsang, Pokeung Eric; Zhao, Dongye

2016-01-01

In this study, the effects of concentrations 0, 100, 250, 500, 750 and 1000 mg kg"−"1 of nanoscale zero-valent iron (nZVI) on germination, seedlings growth, physiology and toxicity mechanisms were investigated. The results showed that nZVI had no effect on germination, but inhibited the rice seedlings growth in higher concentrations (>500 mg kg"−"1 nZVI). The highest suppression rate of the length of roots and shoots reached 46.9% and 57.5%, respectively. The 1000mg kg"−"1 nZVI caused the highest suppression rates for chlorophyll and carotenoids, at 91.6% and 85.2%, respectively. In addition, the activity of antioxidant enzymes was altered by the translocation of nanoparticles and changes in active iron content. Visible symptoms of iron deficiency were observed at higher concentrations, at which the active iron content decreased 61.02% in the shoots, but the active iron content not decreased in roots. Interestingly, the total and available amounts of iron in the soil were not less than those in the control. Therefore, the plants iron deficiency was not caused by (i) deficiency of available iron in the soil and (ii) restraint of the absorption that plant takes in the available iron, while induced by (ⅲ) the transport of active iron from the root to the shoot was blocked. The cortex tissues were seriously damaged by nZVI which was transported from soil to the root, these were proved by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS). This current study shows that the mechanism of iron deficiency in rice seedling was due to transport of active iron from the root to the shoot blocked, which was caused by the uptake of nZVI. - Highlights: • Higher concentrations of nZVI induced iron deficiency in rice seedlings visibly. • nZVI was taken in rice seedlings and transported form root to shoot. • The pathway of active iron transport from root to shoot was inhibited. • The cortex tissues

Design studies for nonimaging light concentrators to be used in very high-energy gamma-ray astronomy

International Nuclear Information System (INIS)

Radu, A.A.Aurelian A.; Mattox, John R.; Ahlen, Steven

2000-01-01

Light concentrators to be used by the camera of a telescope to view gamma-ray-induced Cherenkov light, are analyzed from the point of view of optical efficiency, background rejection capability and manufacturability. A small decrease in the optical efficiency due to multiple reflections undergone by rays incident at small angles in a compound parabolic concentrator is observed. The influence of the angle of incidence on the reflectivity of the wall is analyzed and found to be inconsequential. A closed-packed matrix of concentrators with hexagonal entrance apertures is considered and the light spread in the adjacent pixels introduced by the removal of portions of the surface of concentrators is evaluated

Design studies for nonimaging light concentrators to be used in very high-energy gamma-ray astronomy

Energy Technology Data Exchange (ETDEWEB)

Radu, A.A.Aurelian A.; Mattox, John R.; Ahlen, Steven

2000-05-21

Light concentrators to be used by the camera of a telescope to view gamma-ray-induced Cherenkov light, are analyzed from the point of view of optical efficiency, background rejection capability and manufacturability. A small decrease in the optical efficiency due to multiple reflections undergone by rays incident at small angles in a compound parabolic concentrator is observed. The influence of the angle of incidence on the reflectivity of the wall is analyzed and found to be inconsequential. A closed-packed matrix of concentrators with hexagonal entrance apertures is considered and the light spread in the adjacent pixels introduced by the removal of portions of the surface of concentrators is evaluated.

Atmospheric Concentrations of Organochlorine Pesticides in the ...

African Journals Online (AJOL)

Organochlorine pesticides may still be in use in the Eastern African region for agricultural purposes and for the control of mosquitoes. Atmospheric concentrations of organochlorine pesticides are expected to be higher in the tropics compared to temperate regions due to prevailing high temperatures. However, no study has ...

High Concentrations of Tranexamic Acid Inhibit Ionotropic Glutamate Receptors.

Science.gov (United States)

Lecker, Irene; Wang, Dian-Shi; Kaneshwaran, Kirusanthy; Mazer, C David; Orser, Beverley A

2017-07-01

The antifibrinolytic drug tranexamic acid is structurally similar to the amino acid glycine and may cause seizures and myoclonus by acting as a competitive antagonist of glycine receptors. Glycine is an obligatory co-agonist of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors. Thus, it is plausible that tranexamic acid inhibits NMDA receptors by acting as a competitive antagonist at the glycine binding site. The aim of this study was to determine whether tranexamic acid inhibits NMDA receptors, as well as α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and kainate subtypes of ionotropic glutamate receptors. Tranexamic acid modulation of NMDA, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, and kainate receptors was studied using whole cell voltage-clamp recordings of current from cultured mouse hippocampal neurons. Tranexamic acid rapidly and reversibly inhibited NMDA receptors (half maximal inhibitory concentration = 241 ± 45 mM, mean ± SD; 95% CI, 200 to 281; n = 5) and shifted the glycine concentration-response curve for NMDA-evoked current to the right. Tranexamic acid also inhibited α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (half maximal inhibitory concentration = 231 ± 91 mM; 95% CI, 148 to 314; n = 5 to 6) and kainate receptors (half maximal inhibitory concentration = 90 ± 24 mM; 95% CI, 68 to 112; n = 5). Tranexamic acid inhibits NMDA receptors likely by reducing the binding of the co-agonist glycine and also inhibits α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and kainate receptors. Receptor blockade occurs at high millimolar concentrations of tranexamic acid, similar to the concentrations that occur after topical application to peripheral tissues. Glutamate receptors in tissues including bone, heart, and nerves play various physiologic roles, and tranexamic acid inhibition of these receptors may contribute to adverse drug effects.

Practical design constraints for using secondary concentrators at high temperatures

Energy Technology Data Exchange (ETDEWEB)

O' Gallagher, J.J.; Winston, R.

1999-07-01

The optical advantages of using nonimaging secondary concentrators in two-stage solar thermal dish systems are well understood. However, practical questions having to do with the thermal behavior of any secondary and its possible effects on the performance of cavity type receivers have only recently begun to be investigated. A few years ago an experimental demonstration of a trumpet type nonimaging secondary concentrator was carried out with a cavity receiver operating 660 C in combination with the Cummins Power Generation CPG-460 7.5 kWe concentrator system. Lessons learned from this and previous experiments are reviewed. The tests alleviated any operational concerns about the effectiveness of active water cooling and have shown that secondaries can be operated successfully at high temperatures without significant problems. There was no evidence of direct heat loss from the hot receiver to the cooled trumpet. The optical quality of any primary can be expected to fall well below design goals and to deteriorate further with time. This expectation should be taken into account in planning future experiments and developing new concentrating systems.

Structural changes induced by high-pressure processing in micellar casein and milk protein concentrates.

Science.gov (United States)

Cadesky, Lee; Walkling-Ribeiro, Markus; Kriner, Kyle T; Karwe, Mukund V; Moraru, Carmen I

2017-09-01

Reconstituted micellar casein concentrates and milk protein concentrates of 2.5 and 10% (wt/vol) protein concentration were subjected to high-pressure processing at pressures from 150 to 450 MPa, for 15 min, at ambient temperature. The structural changes induced in milk proteins by high-pressure processing were investigated using a range of physical, physicochemical, and chemical methods, including dynamic light scattering, rheology, mid-infrared spectroscopy, scanning electron microscopy, proteomics, and soluble mineral analyses. The experimental data clearly indicate pressure-induced changes of casein micelles, as well as denaturation of serum proteins. Calcium-binding α S1 - and α S2 -casein levels increased in the soluble phase after all pressure treatments. Pressurization up to 350 MPa also increased levels of soluble calcium and phosphorus, in all samples and concentrations, whereas treatment at 450 MPa reduced the levels of soluble Ca and P. Experimental data suggest dissociation of calcium phosphate and subsequent casein micelle destabilization as a result of pressure treatment. Treatment of 10% micellar casein concentrate and 10% milk protein concentrate samples at 450 MPa resulted in weak, physical gels, which featured aggregates of uniformly distributed, casein substructures of 15 to 20 nm in diameter. Serum proteins were significantly denatured by pressures above 250 MPa. These results provide information on pressure-induced changes in high-concentration protein systems, and may inform the development on new milk protein-based foods with novel textures and potentially high nutritional quality, of particular interest being the soft gel structures formed at high pressure levels. The Authors. Published by the Federation of Animal Science Societies and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

Extremely high hole concentrations in c-plane GaN

Energy Technology Data Exchange (ETDEWEB)

Trybus, Elaissa; Moseley, Michael; Henderson, Walter; Billingsley, Daniel [Department of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA (United States); Namkoong, Gon [Old Dominion University, Applied Research Center, Newport News, VA (United States); Look, David C. [Wright State University, Semiconductor Research Center, Dayton, OH (United States); Doolittle, W.A.

2009-06-15

Metal Modulated Epitaxy (S. D. Burnham et al., J. Appl. Phys. 104, 024902 (2008)[1]) is extended to include modulation of both the shutters of Ga and Mg, the Mg being delivered from a Veeco corrosive series valved cracker (S. D. Burnham et al., Mater. Res. Soc. Proc. 798, Y8.11 (2003)[2]). The Ga fluxes used are sufficiently large that droplets rapidly form when the Ga shutter opens and are subsequently depleted when the Ga shutter closes. The result is the ability to limit surface faceting while predominantly growing under average N-rich growth conditions and thus, possibly reduce N-vacancy defects. N-vacancy defects are known to result in compensation. This ability to grow higher quality materials under N-rich conditions results in very high hole concentrations and low resistivity p-type materials. Hole concentrations as high as 2 x 10{sup 19} cm{sup -3} have been achieved on c-plane GaN resulting in resistivities as low as 0.38 ohm-cm. The dependence on Ga flux, shutter timing, the corresponding RHEED images for each condition is detailed and clearly show minimization of faceting and crystal quality variations as determined by X-ray diffraction. Quantification of the Mg incorporation and residual impurities such as hydrogen, oxygen, and carbon by SIMS, eliminates co-doping, while temperature dependent hall measurements show reduced activation energies. X-ray diffraction data compares crystalline quality with hole concentration. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Phenomenon of energy concentration in super-high energy γ-hadron families

International Nuclear Information System (INIS)

Dai Zhiqiang; Xue Liang; Li Jinyu; Zhang Xueyao; Feng Cunfeng; Fu Yu; Li Jie; Cao Peiyuan; Zhang Naijian; He Mao; Wang Chengrui; Ren Jingru; Lu Suiling

2000-01-01

The family events observed with iron emulsion chambers at Mt. Kanbala are analyzed and compared with the simulations by the COSMOS code and CORSIKA code respectively. A detailed study on the production of super-high energy γ-hadron families with energy concentration behavior is carried out. The preliminary conclusions are: 1) the energy concentration behavior of super-high energy γ-hadron families is the external embodiment of high energy central shower clusters contained in the families. 2) the mean lateral spread of these clusters is about 0.37 cm. 3) the frequency of this phenomenon appeared under the conditions of R≤10 mm and X 10 ≥90% is (20.5 +- 3.1)%. 4) compared to the COSMOS code based on the phenomenological multi-cluster model, the simulation by the CORSIKA code that adopts SIBYLL model is closer to the analytical results of experiment

High-dimensional orbital angular momentum entanglement concentration based on Laguerre–Gaussian mode selection

International Nuclear Information System (INIS)

Zhang, Wuhong; Su, Ming; Wu, Ziwen; Lu, Meng; Huang, Bingwei; Chen, Lixiang

2013-01-01

Twisted photons enable the definition of a Hilbert space beyond two dimensions by orbital angular momentum (OAM) eigenstates. Here we propose a feasible entanglement concentration experiment, to enhance the quality of high-dimensional entanglement shared by twisted photon pairs. Our approach is started from the full characterization of entangled spiral bandwidth, and is then based on the careful selection of the Laguerre–Gaussian (LG) modes with specific radial and azimuthal indices p and ℓ. In particular, we demonstrate the possibility of high-dimensional entanglement concentration residing in the OAM subspace of up to 21 dimensions. By means of LabVIEW simulations with spatial light modulators, we show that the Shannon dimensionality could be employed to quantify the quality of the present concentration. Our scheme holds promise in quantum information applications defined in high-dimensional Hilbert space. (letter)

Development of automatic high-concentration boron measurement technique; Konodo hoso jido sokutei gijutsu no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Maeda, T.; Honda, S.; Ito, A. [Kyushu Electric Power Co. Inc., Fukuoka (Japan)

1997-03-01

The technology that can automatically measure the boron concentration in boric acid water was developed. A high-concentration boric acid solution must be held at a high temperature to prevent the deposition. Skill and precision ({plus_minus}0.2 to 0.3% for 10 to 2500 ppm as boron concentration, and {plus_minus}2 to 3% for 2500 to 25,000 ppm) are required to analyze the boric acid solution manually. In theory, the boron concentration in a wide range can be measured, and boron has a constant-temperature function. A density hydrometer method that facilitates the treatment and calibration in high precision and at low cost was chosen. The vibration period generated when vibration is given to the solution specimen put in a U-tube is higher as the density is lower. On the basis of this theory, the density of a specimen can be obtained according to the relation with the same data of the known-concentration boric acid water. The high-concentration boric acid water that cannot be measured by the existing boron densitometer can be measured directly. It can also be measured in a low-concentration area. The technique can be used in a laboratory as the simplified method that is replaced by the current manual analysis. The reduction effect of analytical chemical`s waste liquid can also be expected. In the electric power industry, automated equipment is required for high efficiency and labor saving. 13 figs., 3 tabs.

High-voltage electrical burns due to copper theft - Case series.

Science.gov (United States)

Braga, M J; Oliveira, I; Egipto, P; Silva, A

2016-03-31

Electrical burns are among the most devastating trauma inflicted on the human body. These burns have a higher morbidity, length of stay and a much higher risk of amputation than any other type of burn. Electrical burns affect mostly young, working males because they are more frequently the result of a work accident. However, possibly due to the worldwide economic crisis, we are experiencing a new phenomenon: the theft of high-voltage copper wiring.

Application of Hydrothermal Treatment to High Concentrated Sewage Sludge for Anaerobic Digestion Process

OpenAIRE

M. Orikawa; H. Kamahara; Y. Atsuta; H. Daimon

2013-01-01

Tomato and seaweed were produced by utilizing CO2 and heat discharged from power generation using biogas in Toyogawa biomass park, Japan. The biogas was obtained by anaerobic digestion with hydrothermal treatment. The hydrothermal treatment was applied to the high concentrated sewage sludge (22 % total solids (TS) dewatered sludge). The purpose of this study is to clarify the effect of hydrothermal treatment on the qualities of high concentrated sewage sludge, by analyzing particulate organic...

Environmental 238U and 232Th concentration measurements in an area of high level natural background radiation at Palong, Johor, Malaysia.

Science.gov (United States)

Ramli, A Termizi; Hussein, A Wahab M A; Wood, A Khalik

2005-01-01

Concentrations of uranium-238 and thorium-232 in soil, water, grass, moss and oil-palm fruit samples collected from an area of high background radiation were determined using neutron activation analysis (NAA). U-238 concentration in soil ranged from 4.9 mg kg(-1) (58.8 Bq kg(-1)) to 40.4 mg kg(-1) (484.8 Bq kg(-1)), Th-232 concentration ranged from 14.9 mg kg(-1) (59.6 Bq kg(-1)) to 301.0 mg kg(-1) (1204 Bq kg(-1)). The concentration of U-238 in grass samples ranged from below the detection limit to 0.076 mg kg(-1) (912 mBq kg(-1)), and Th-232 ranged from 0.008 mg kg(-1) (32 mBq kg(-1)) to 0.343 mg kg(-1) (1.372 Bq kg(-1)). U-238 content in water samples ranged from 0.33 mg kg(-1) (4.0 Bq L(-1)) to 1.40 mg kg(-1) (16.8 Bq L(-1)), and Th-232 ranged from 0.19 mg kg(-1) (0.76 Bq L(-1)) to 0.66 mg kg(-1) (2.64 Bq L(-1)). It can be said that the concentrations of environmental U-238 and Th-232 in grass and water samples in the study area are insignificant. Mosses were found to be possible bio-radiological indicators due to their high absorption of the heavy radioelements from the environment.

Particulate Matter Concentrations in East Oakland's High Street Corridor

Science.gov (United States)

Lei, P.; Jackson, J.; Lewis, R.; Marigny, A.; Mitchell, J. D.; Nguyen, R.; Philips, B.; Randle, D.; Romero, D.; Spears, D.; Telles, C.; Weissman, D.

2012-12-01

Particulate matter (PM) is a complex mixture of small solid pieces and/or liquid droplets in the air. High concentrations of PM can pose a serious health hazard because inhalation can result in breathing problems and/or aggravate asthma. Long term exposure can increase the likelihood of respiratory problems like asthma and emphysema as well as cancer. The smaller the particles, the deeper they can get into the respiratory system. For this reason, the smallest particles, those smaller than 2.5 micrometers in diameter (PM2.5), are the most dangerous. PM2.5 is largely emitted from motor vehicles burning fuels that don't break down fully. Our research team investigated the levels of PM2.5 as well as particles smaller than 10 micrometers (PM10) and total suspended particulate (TSP) along the northeast-southwest trending High Street Corridor, near Fremont High School in East Oakland, California. Using the Aerocet 531 mass particle counter, team members walked through neighborhoods and along major roads within a 1 mile radius of Fremont High School. The Aerocet 531 recorded two minute average measurements of all the relevant PM sizes, which are reported in mg/m3. Measurements were consistently taken in the morning, between 8:30 and 11:30 am. Preliminary results indicate maximum readings of all PM sizes at sites that are in close proximity to a major freeway (Interstate-880). These results support our initial hypothesis that proximity to major roads and freeways, especially those with high diesel-fuel burning truck traffic, would be the primary factor affecting PM concentration levels. Preliminary median and maximum readings all suggest particulate matter levels below what the EPA would consider unhealthy or risky.

Description and measurement of concentration problems in depressed patients.

Science.gov (United States)

Watts, F N; Sharrock, R

1985-05-01

Depressed patients commonly complain of concentration problems, yet these have seldom been the focus of systematic investigation. A structured interview about concentration problems was administered to a group of relatively severely depressed patients. Problems in reading and watching television were the most common, and were highly correlated with each other. Direct report of the number of concentration lapses on a reading task was the most generally satisfactory task-performance correlate of complaints of reading/TV concentration problems. Evidence both from this task and from the interview suggests that depressive concentration problems may often be due to 'mind-wandering'. The correlations with concentration problems with the severity and endogeneity of depression and with state anxiety were generally similar.

Comparative analysis of methods for concentrating venom from jellyfish Rhopilema esculentum Kishinouye

Science.gov (United States)

Li, Cuiping; Yu, Huahua; Feng, Jinhua; Chen, Xiaolin; Li, Pengcheng

2009-02-01

In this study, several methods were compared for the efficiency to concentrate venom from the tentacles of jellyfish Rhopilema esculentum Kishinouye. The results show that the methods using either freezing-dry or gel absorption to remove water to concentrate venom are not applicable due to the low concentration of the compounds dissolved. Although the recovery efficiency and the total venom obtained using the dialysis dehydration method are high, some proteins can be lost during the concentrating process. Comparing to the lyophilization method, ultrafiltration is a simple way to concentrate the compounds at high percentage but the hemolytic activities of the proteins obtained by ultrafiltration appear to be lower. Our results suggest that overall lyophilization is the best and recommended method to concentrate venom from the tentacles of jellyfish. It shows not only the high recovery efficiency for the venoms but high hemolytic activities as well.

Characterisation of PM2.5 concentrations and turbulent fluxes on a island of the Venice lagoon using high temporal resolution measurements

Energy Technology Data Exchange (ETDEWEB)

Donateo, A.; Contini, D.; Cesari, D. [CNR-ISAC, Istituto di Scienze dell' Atmosfera e del Clima, Lecce (Italy); Belosi, F.; Santachiara, G.; Prodi, F. [CNR-ISAC, Istituto di Scienze dell' Atmosfera e del Clima, Bologna (Italy); Gambaro, A. [Venice Univ. (Italy). Environmental Sciences Dept.

2012-08-15

This work presents an analysis of PM2.5 concentrations and vertical turbulent fluxes on an island of the Venice lagoon. Data were collected during three measurement campaigns in spring, summer and winter periods. Measurements were taken with a high-resolution optical PM2.5 detector, coupled with a micrometeorological station that allowed the evaluation of the vertical turbulent fluxes of PM2.5 using the eddy-correlation technique. The main objective of this paper is to analyse the daily and seasonal pattern in PM2.5 concentrations and fluxes and to discuss their correlation with the main meteorological and micrometeorological parameters using high temporal resolution measurements. Observed data showed a seasonal pattern in turbulent fluxes with daytime average positive value during winter and negative during summer. Deposition velocities, ranged from -60 to 20 mm/s, appeared to be mainly influenced by atmospheric stability. There were larger emissions in cases of high wind velocities blowing from water sector indicating a significant potential contribution of sea spray to PM2.5 fluxes. The local atmospheric circulation, due to the orography of the area, was characterised by diurnal winds coming from the Adriatic Sea and nocturnal wind coming from the Alps. This circulation influenced deposition velocity creating an increase of negative fluxes in the morning at the starting of the sea breeze. A diurnal pattern in concentration has been observed and it is similar for all three measurement campaigns, with higher concentrations in nocturnal periods. The daily pattern was investigated in terms of its correlation with meteorological and micro-meteorological parameters, and was found highly correlated with the diurnal pattern of boundary layer height (BLH) and with relative humidity. (orig.)

Clinical characteristics and treatment outcomes of patients with low- and high-concentration isoniazid-monoresistant tuberculosis.

Directory of Open Access Journals (Sweden)

Tsai-Yu Wang

Full Text Available BACKGROUND: Isoniazid (INH resistance is now the most common type of tuberculosis (TB infection resistance worldwide. The aim of this study was to evaluate the clinical characteristics and treatment outcomes of patients with low- and high-concentration INH-monoresistant TB. METHODS: One hundred and thirty-four patients with culture-confirmed INH-monoresistant TB during 2006 January to 2007 December were retrospectively enrolled. INH resistance was classified as either low-concentration or high-concentration resistance according to the critical concentrations of 0.2 µg/mL or 1 µg/mL of INH, respectively. The patients' clinical outcomes, treatment regimens, and treatment duration were analyzed. RESULTS: The treatment success rates between low- and high-concentration INH-resistant TB were similar (81.8% vs. 86.7%. The treatment regimens and treatment duration were similar between both groups. Only a minor percentage of the patients in both groups received 6-month treatment regimens (low vs. high concentration resistance, 9.1% vs. 13.3%; respectively, p = 0.447 The most common reason for treatment duration longer than 6 months was pyrazinamide given for less than 6 months, followed by a delay in clinical response to treatment. Multivariable analysis showed that prior tuberculosis treatment (Odds ratio, 2.82, 95% C.I., 1.02-7.77, p = 0.045 was the only independent risk factor for unsuccessful treatment outcome. CONCLUSION: Different levels of INH resistance did not affect the treatment outcomes of patients with INH-monoresistant tuberculosis. Prolonged Rifampin-containing regimens may achieve those good outcomes in patients with low- and high-concentration INH-monoresistant TB.

Separation and Concentration without Clogging Using a High-Throughput Tunable Filter

Science.gov (United States)

Mossige, E. J.; Jensen, A.; Mielnik, M. M.

2018-05-01

We present a detailed experimental study of a hydrodynamic filtration microchip and show how chip performance can be tuned and clogging avoided by adjusting the flow rates. We demonstrate concentration and separation of microspheres at throughputs as high as 29 ml /min and with 96% pureness. Results of streakline visualizations show that the thickness of a tunable filtration layer dictates the cutoff size and that two different concentration mechanisms exist. Particles larger than pores are concentrated by low-velocity rolling over the filtration pillars, while particles smaller than pores are concentrated by lateral drift across the filtration layer. Results of microscopic particle image velocimetry and particle-tracking velocimetry show that the degree of lateral migration can be quantified by the slip velocity between the particle and the surrounding fluid. Finally, by utilizing differences in inertia and separation mode, we demonstrate size-based separation of particles in a mixture.

Concentration of radiocaesium in grain following the Chernobyl accident

International Nuclear Information System (INIS)

Kanyar, B.; Czegledi, P.; Kerekes, A.; Kovacs, L.; Sohar, J.; Sztanyik, L.B.

1991-01-01

Radioactivity measurements and dose assessments in Hungary after the Chernobyl accident have shown that the consumption of baker's ware contributes significantly to the internal dose of man. Flour and bread have been contaminated mainly due to radiocaesium deposition onto the of cereals at the end of April and beginning of May, 1986. Because of the different seasonal and growing conditions of biomass, the interception fraction of the standing winter wheat became higher than that of the summer wheat. Therefore, the contribution of grain to the internal dose was relatively high in Hungary where near to 90 per cent of flour and bread is produced from winter wheat in comparison with other countries. The average concentration of 137 Cs in winter grain harvested in summer 1986 was 32 Bq/kg with a range of 11-140 Bq/kg. The bran contained almost half of the total radiocaesium of the grain with about 20 per cent of the weight. The 40 K concentration of grain was 149 Bq/kg. The 137 Cs concentration in white bread commonly used in Hungary was 22 Bq/kg in average. The concentrations found in bread samples from the whole country showed a high variation due to the uneven deposition of radioactive substances. The 137 Cs concentration in winter grain was 0.0075±0.0017 Bq/kg normalized to 1 Bq/m 2 deposition density. The 137 Cs concentration in grain harvested in 1987 or later became less than 1 Bq/kg. It suggests that the root uptake of radiocaesium by cereals must be very small. The per caput committed effective dose equivalent due to consumption of baker's ware was estimated as 50 micro-Sv. (author)

Compact high-flux two-stage solar collectors based on tailored edge-ray concentrators

Science.gov (United States)

Friedman, Robert P.; Gordon, Jeffrey M.; Ries, Harald

1995-08-01

Using the recently-invented tailored edge-ray concentrator (TERC) approach for the design of compact two-stage high-flux solar collectors--a focusing primary reflector and a nonimaging TERC secondary reflector--we present: 1) a new primary reflector shape based on the TERC approach and a secondary TERC tailored to its particular flux map, such that more compact concentrators emerge at flux concentration levels in excess of 90% of the thermodynamic limit; and 2) calculations and raytrace simulations result which demonstrate the V-cone approximations to a wide variety of TERCs attain the concentration of the TERC to within a few percent, and hence represent practical secondary concentrators that may be superior to corresponding compound parabolic concentrator or trumpet secondaries.

Increased albumin excretion in industrial workers due to shift work rather than to prolonged exposure to low concentrations of chlorinated hydrocarbons.

OpenAIRE

Boogaard, P J; Caubo, M E

1994-01-01

OBJECTIVES--It has been reported that groups of workers in petrochemical industries who have been exposed to low concentrations of chemicals for prolonged periods have an increased urinary albumin excretion compared with unexposed controls. This increase, however, seemed to be unrelated to the extent, duration, and type of exposure. The aim of the present study was to investigate the suggestion that the small increase in albumin excretion might be due to differences in physical workload betwe...

A nationwide survey of radon concentration in Japan. Indoor, outdoor and workplace

International Nuclear Information System (INIS)

Sanada, Tetsuya; Oikawa, Shinji; Kanno, Nobuyuki; Abukawa, Johji; Higuchi, Hideo

2004-01-01

The nationwide indoor, outdoor and workplace radon concentrations were surveyed in Japan. These surveys were conducted to estimate the natural radiation dose due to radon and its progeny for the general public. The radon concentration was measured using passive type radon monitor. The number of radon monitors were installed at indoor, outdoor and workplace for 940 houses, 705 points and 705 sites, respectively. The radon concentration was measured for one year at each measurement site. Annual mean radon concentration was obtained from four quarters measurements of 47 prefectures in Japan. The nationwide indoor, outdoor and workplace annual mean radon concentration were 15.5 Bq m -3 , 6.1 Bq m -3 and 20.8 Bq m -3 , respectively. Their radon concentration shows approximately a logarithmic normal distribution. Workplace showed relatively high radon concentration compared with other environments, may be due to construction materials and low ventilation rate. The indoor radon concentration found to be seasonal variation and architectural dependences. Seasonal variation and regional distribution of outdoor radon concentration was also observed. From the results of these radon surveys, the annual effective dose to the general public due to radon and its progeny was estimated to be 0.49 mSv y -1 in Japan. (author)

High Concentrations of Measles Neutralizing Antibodies and High-Avidity Measles IgG Accurately Identify Measles Reinfection Cases

Science.gov (United States)

Rota, Jennifer S.; Hickman, Carole J.; Mercader, Sara; Redd, Susan; McNall, Rebecca J.; Williams, Nobia; McGrew, Marcia; Walls, M. Laura; Rota, Paul A.; Bellini, William J.

2016-01-01

In the United States, approximately 9% of the measles cases reported from 2012 to 2014 occurred in vaccinated individuals. Laboratory confirmation of measles in vaccinated individuals is challenging since IgM assays can give inconclusive results. Although a positive reverse transcription (RT)-PCR assay result from an appropriately timed specimen can provide confirmation, negative results may not rule out a highly suspicious case. Detection of high-avidity measles IgG in serum samples provides laboratory evidence of a past immunologic response to measles from natural infection or immunization. High concentrations of measles neutralizing antibody have been observed by plaque reduction neutralization (PRN) assays among confirmed measles cases with high-avidity IgG, referred to here as reinfection cases (RICs). In this study, we evaluated the utility of measuring levels of measles neutralizing antibody to distinguish RICs from noncases by receiver operating characteristic curve analysis. Single and paired serum samples with high-avidity measles IgG from suspected measles cases submitted to the CDC for routine surveillance were used for the analysis. The RICs were confirmed by a 4-fold rise in PRN titer or by RT-quantitative PCR (RT-qPCR) assay, while the noncases were negative by both assays. Discrimination accuracy was high with serum samples collected ≥3 days after rash onset (area under the curve, 0.953; 95% confidence interval [CI], 0.854 to 0.993). Measles neutralizing antibody concentrations of ≥40,000 mIU/ml identified RICs with 90% sensitivity (95% CI, 74 to 98%) and 100% specificity (95% CI, 82 to 100%). Therefore, when serological or RT-qPCR results are unavailable or inconclusive, suspected measles cases with high-avidity measles IgG can be confirmed as RICs by measles neutralizing antibody concentrations of ≥40,000 mIU/ml. PMID:27335386

Novel bioevaporation process for the zero-discharge treatment of highly concentrated organic wastewater.

Science.gov (United States)

Yang, Benqin; Zhang, Lei; Lee, Yongwoo; Jahng, Deokjin

2013-10-01

A novel process termed as bioevaporation was established to completely evaporate wastewater by metabolic heat released from the aerobic microbial degradation of the organic matters contained in the highly concentrated organic wastewater itself. By adding the glucose solution and ground food waste (FW) into the biodried sludge bed, the activity of the microorganisms in the biodried sludge was stimulated and the water in the glucose solution and FW was evaporated. As the biodegradable volatile solids (BVS) concentration in wastewater increased, more heat was produced and the water removal ratio increased. When the volatile solids (VS) concentrations of both glucose and ground FW were 120 g L(-1), 101.7% and 104.3% of the added water was removed, respectively, by completely consuming the glucose and FW BVS. Therefore, the complete removal of water and biodegradable organic contents was achieved simultaneously in the bioevaporation process, which accomplished zero-discharge treatment of highly concentrated organic wastewater. Copyright © 2013 Elsevier Ltd. All rights reserved.

Physiological responses of sweet potato (Ipomoea batatas L. plants due to different copper concentrations

Directory of Open Access Journals (Sweden)

Cristina Copstein Cuchiara

2015-12-01

Full Text Available At low concentrations, Cu is considered as an essential micronutrient for plants and as a constituent and activator of several enzymes. However, when in excess, Cu can negatively affect plant growth and metabolism. Therefore, the aim of this study was to evaluate physiological responses of sweet potato plants at different Cu concentrations by measuring morphological parameters, antioxidant metabolism, stomatal characteristics, and mineral profile. For this purpose, sweet potato plants were grown hydroponically in complete nutrient solution for six days. Then, the plants were transferred to solutions containing different Cu concentrations, 0.041 (control, 0.082, and 0.164 mM, and maintained for nine days. The main effect of increased Cu concentration was observed in the roots. The sweet potato plants grown in 0.082 mM Cu solution showed increased activity of antioxidant enzymes and no changes in growth parameters. However, at a concentration of 0.164 mM, Cu was transported from the roots to the shoots. This concentration altered morpho-anatomical characteristics and activated the antioxidant system because of the stress generated by excess Cu. On the basis of the results, it can be concluded that the sweet potato plants were able to tolerate Cu toxicity until 0.082 mM.

Concentration of 188Re-Perrhenate for Therapeutic Radiopharmaceuticals

International Nuclear Information System (INIS)

Bokhari, T.H.; Hina, S.; Ahmad, M.; Iqbal, M.

2013-01-01

Summary: Rhenium-188 (T1/2=16.9h) has great potential for a variety of therapeutic applications, including radionuclide synovectomy, oncology and bone pain palliation. The radioactive concentration of 188Re is dependent upon the specific activity of 188W, which dictates the bed size of the alumina/gel column. Due to the high content of inactive tungsten in neutron irradiated WO3, large columns containing aluminum oxide or gel are needed to prepare to double neutron capture based 188W/188Re generators that results in large elution volumes containing relatively high188W contents and low concentrations of /sup 188/ ReO/sub 4/ This decrease in specific volume of 188ReO/sub 4/ places a limitation because a high radioactive concentration of 188ReO4 - is always needed for filling angioplasty balloons or other therapeutic radiopharmaceuticals like188Re -EHDP 188Re -EDTMP, 188Re - MAG3 and 188Re -DTPA. We report post elution concentration of 188ReO4 - using in- house prepared lead cation exchange and alumina columns. Using these columns high bolus volume (10 mL saline) of 188ReO4 - can conveniently be concentrated in 1 mL of physiological saline for therapeutic use. (author)

Parabolic solar concentrator

Science.gov (United States)

Tecpoyotl-Torres, M.; Campos-Alvarez, J.; Tellez-Alanis, F.; Sánchez-Mondragón, J.

2006-08-01

In this work we present the basis of the solar concentrator design, which has is located at Temixco, Morelos, Mexico. For this purpose, this place is ideal due to its geographic and climatic conditions, and in addition, because it accounts with the greatest constant illumination in Mexico. For the construction of the concentrator we use a recycled parabolic plate of a telecommunications satellite dish (NEC). This plate was totally covered with Aluminum. The opening diameter is of 332 cm, the focal length is of 83 cm and the opening angle is of 90°. The geometry of the plate guaranties that the incident beams, will be collected at the focus. The mechanical treatment of the plate produces an average reflectance of 75% in the visible region of the solar spectrum, and of 92% for wavelengths up to 3μm in the infrared region. We obtain up to 2000°C of temperature concentration with this setup. The reflectance can be greatly improved, but did not consider it as typical practical use. The energy obtained can be applied to conditions that require of those high calorific energies. In order to optimize the operation of the concentrator we use a control circuit designed to track the apparent sun position.

IMPACT OF OXYGEN CONCENTRATION ON ZEBRA MUSSEL MORTALITY

Energy Technology Data Exchange (ETDEWEB)

Daniel P. Molloy

2003-01-27

These tests have indicated that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels in environments having dissolved oxygen (DO) concentrations ranging from very low to very high. The results suggest that the highest mussel kill can be achieved in moderately to highly aerated environments, while kill may be 0-20% lower under conditions of very low oxygen. For example, under highly oxygenated conditions 97% kill was achieved while conditions having low DO produced 79% mussel kill. Service water measured in a local power plant indicated that DO concentrations were in the range of 8-9 ppm (e.g., highly aerated) within their pipes. Therefore, we will not expect to see decreases in the efficacy of CL0145A treatments due to oxygen levels within such power plant pipes.

IMPACT OF OXYGEN CONCENTRATION ON ZEBRA MUSSEL MORTALITY

International Nuclear Information System (INIS)

Molloy, Daniel P.

2003-01-01

These tests have indicated that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels in environments having dissolved oxygen (DO) concentrations ranging from very low to very high. The results suggest that the highest mussel kill can be achieved in moderately to highly aerated environments, while kill may be 0-20% lower under conditions of very low oxygen. For example, under highly oxygenated conditions 97% kill was achieved while conditions having low DO produced 79% mussel kill. Service water measured in a local power plant indicated that DO concentrations were in the range of 8-9 ppm (e.g., highly aerated) within their pipes. Therefore, we will not expect to see decreases in the efficacy of CL0145A treatments due to oxygen levels within such power plant pipes

Magnetic Field Fluctuations Due to Diel Vertical Migrations of Zooplankton

Science.gov (United States)

Dean, C.; Soloviev, A.

2016-12-01

Dean et al. (2016) have indicated that at high zooplankton concentrations, diel vertical migrations (DVM) cause velocity fluctuations and a respective increase of the dissipation rate of turbulent kinetic energy (TKE). In this work, we used a 3D non-hydrostatic computational fluid dynamics model with Lagrangian particle injections (a proxy for migrating organisms) via a discrete phase model to simulate the effect of turbulence generation by DVM. We tested a range of organism concentrations from 1000 to 10,000 organisms/m3. The simulation at an extreme concentration of zooplankton showed an increase in dissipation rate of TKE by two to three orders of magnitude during DVM over background turbulence, 10-8 W kg-1. At lower concentrations (Frank, J. Wood, 2016: Biomixing due to diel vertical migrations of zooplankton. Ocean Modelling 98, 51-64.

Fibrinogen and thrombin concentrations are critical for fibrin glue adherence in rat high-risk colon anastomoses

Directory of Open Access Journals (Sweden)

Eliseo Portilla-de Buen

2014-04-01

Full Text Available OBJECTIVE: Fibrin glues have not been consistently successful in preventing the dehiscence of high-risk colonic anastomoses. Fibrinogen and thrombin concentrations in glues determine their ability to function as sealants, healers, and/or adhesives. The objective of the current study was to compare the effects of different concentrations of fibrinogen and thrombin on bursting pressure, leaks, dehiscence, and morphology of high-risk ischemic colonic anastomoses using fibrin glue in rats. METHODS: Colonic anastomoses in adult female Sprague-Dawley rats (weight, 250-350 g treated with fibrin glue containing different concentrations of fibrinogen and thrombin were evaluated at post-operative day 5. The interventions were low-risk (normal or high-risk (ischemic end-to-end colonic anastomoses using polypropylene sutures and topical application of fibrinogen at high (120 mg/mL or low (40 mg/mL concentrations and thrombin at high (1000 IU/mL or low (500 IU/mL concentrations. RESULTS: Ischemia alone, anastomosis alone, or both together reduced the bursting pressure. Glues containing a low fibrinogen concentration improved this parameter in all cases. High thrombin in combination with low fibrinogen also improved adherence exclusively in low-risk anastomoses. No differences were detected with respect to macroscopic parameters, histopathology, or hydroxyproline content at 5 days post-anastomosis. CONCLUSIONS: Fibrin glue with a low fibrinogen content normalizes the bursting pressure of high-risk ischemic left-colon anastomoses in rats at day 5 after surgery.

Preparation of ultra-light magnetic nanocomposites using highly concentrated emulsions

Energy Technology Data Exchange (ETDEWEB)

Ghosh, Goutam; Vilchez, Alejandro; Esquena, Jordi; Solans, Conxita [Instituto de Quimica Avanzada de Cataluna, Consejo Superior de Investigaciones Cientificas (IQAC-CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); Rodriguez-Abreu, Carlos, E-mail: carlos.rodriguez@inl.int [Instituto de Quimica Avanzada de Cataluna, Consejo Superior de Investigaciones Cientificas (IQAC-CSIC), Jordi Girona 18-26, 08034 Barcelona (Spain); International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jose Veiga, 4715-330 Braga (Portugal)

2011-10-17

Highlights: {yields} Polystyrene-divinylbenzene-iron oxide nanocomposites. {yields} Porous magnetic nanocomposites from highly concentrated emulsions. {yields} Ultralight materials with relatively high magnetic moment. - Abstract: Hybrid inorganic-organic ultra-light magnetic solid foams with iron oxide nanoparticles embedded in a divinylbenzene-polystyrene matrix were prepared using a highly concentrated emulsion polymerization method. Iron oxide nanoparticles with diameters of 3 and 10 nm were synthesized using two different methods. For comparison purposes, nanocomposites with magnetite nanoparticles dispersed in a non-porous polymeric matrix obtained by bulk polymerization were also investigated. Materials were characterized using several techniques such as dynamic light scattering (DLS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), small angle X-ray scattering (SAXS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and magnetization measurements. SEM and TEM images showed that solid foams are made of well-defined macro pores with nanoparticles embedded in the walls. The density of the solid foams was ca. 50-70 kg m{sup -3}, which is about 20 times lighter than the non-porous monoliths. The magnetic measurements show that both nanocomposites are superparamagnetic, and that there are differences regarding the interparticle interactions depending on matrix porosity. The synthesized materials may find applications in adsorbents, tissue reparation, enzyme supports, microreactors, or in water decontamination.

Preparation of ultra-light magnetic nanocomposites using highly concentrated emulsions

International Nuclear Information System (INIS)

Ghosh, Goutam; Vilchez, Alejandro; Esquena, Jordi; Solans, Conxita; Rodriguez-Abreu, Carlos

2011-01-01

Highlights: → Polystyrene-divinylbenzene-iron oxide nanocomposites. → Porous magnetic nanocomposites from highly concentrated emulsions. → Ultralight materials with relatively high magnetic moment. - Abstract: Hybrid inorganic-organic ultra-light magnetic solid foams with iron oxide nanoparticles embedded in a divinylbenzene-polystyrene matrix were prepared using a highly concentrated emulsion polymerization method. Iron oxide nanoparticles with diameters of 3 and 10 nm were synthesized using two different methods. For comparison purposes, nanocomposites with magnetite nanoparticles dispersed in a non-porous polymeric matrix obtained by bulk polymerization were also investigated. Materials were characterized using several techniques such as dynamic light scattering (DLS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), small angle X-ray scattering (SAXS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and magnetization measurements. SEM and TEM images showed that solid foams are made of well-defined macro pores with nanoparticles embedded in the walls. The density of the solid foams was ca. 50-70 kg m -3 , which is about 20 times lighter than the non-porous monoliths. The magnetic measurements show that both nanocomposites are superparamagnetic, and that there are differences regarding the interparticle interactions depending on matrix porosity. The synthesized materials may find applications in adsorbents, tissue reparation, enzyme supports, microreactors, or in water decontamination.

Enhanced Cycling Stability of Rechargeable Li-O2 Batteries Using High Concentration Electrolytes

Energy Technology Data Exchange (ETDEWEB)

Liu, Bin; Xu, Wu; Yan, Pengfei; Sun, Xiuliang; Bowden, Mark E.; Read, Jeffrey; Qian, Jiangfeng; Mei, Donghai; Wang, Chong M.; Zhang, Jiguang

2016-01-26

The electrolyte stability against reactive reduced-oxygen species is crucial for the development of rechargeable Li-O2 batteries. In this work, we systematically investigated the effect of lithium salt concentration in 1,2-dimethoxyethane (DME)-based electrolytes on the cycling stability of Li-O2 batteries. Cells with high concentration electrolyte illustrate largely enhanced cycling stability under both the full discharge/charge (2.0-4.5 V vs. Li/Li+) and the capacity limited (at 1,000 mAh g-1) conditions. These cells also exhibit much less reaction-residual on the charged air electrode surface, and much less corrosion to the Li metal anode. The density functional theory calculations are conducted on the molecular orbital energies of the electrolyte components and the Gibbs activation barriers for superoxide radical anion to attack DME solvent and Li+-(DME)n solvates. In a highly concentrated electrolyte, all DME molecules have been coordinated with salt and the C-H bond scission of a DME molecule becomes more difficult. Therefore, the decomposition of highly concentrated electrolyte in a Li-O2 battery can be mitigated and both air-cathodes and Li-metal anodes exhibits much better reversibility. As a results, the cyclability of Li-O2 can be largely improved.

Inactivation of high concentration of pathogens in land-applied food ...

African Journals Online (AJOL)

2008-10-16

Oct 16, 2008 ... In Mexico, as in other developing countries, the most important pollution and management problems of food-processing sludge are the high levels .... or ammonia is reduced due to its dilution in the water contained in sludge.

Acute oxalate nephropathy due to ′Averrhoa bilimbi′ fruit juice ingestion

Directory of Open Access Journals (Sweden)

G Bakul

2013-01-01

Full Text Available Irumban puli (Averrhoa bilimbi is commonly used as a traditional remedy in the state of Kerala. Freshly made concentrated juice has a very high oxalic acid content and consumption carries a high risk of developing acute renal failure (ARF by deposition of calcium oxalate crystals in renal tubules. Acute oxalate nephropathy (AON due to secondary oxalosis after consumption of Irumban puli juice is uncommon. AON due to A. bilimbi has not been reported before. We present a series of ten patients from five hospitals in the State of Kerala who developed ARF after intake of I. puli fruit juice. Seven patients needed hemodialysis whereas the other three improved with conservative management.

Evaluation of Activity Concentration Values and Doses due to the Transport of Low Level Radioactive Material

Energy Technology Data Exchange (ETDEWEB)

Rawl, Richard R [ORNL; Scofield, Patricia A [ORNL; Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL

2010-04-01

The International Atomic Energy Agency (IAEA) initiated an international Coordinated Research Project (CRP) to evaluate the safety of transport of naturally occurring radioactive material (NORM). This report presents the United States contribution to that IAEA research program. The focus of this report is on the analysis of the potential doses resulting from the transport of low level radioactive material. Specific areas of research included: (1) an examination of the technical approach used in the derivation of exempt activity concentration values and a comparison of the doses associated with the transport of materials included or not included in the provisions of Paragraph 107(e) of the IAEA Safety Standards, Regulations for the Safe Transport of Radioactive Material, Safety Requirements No. TS-R-1; (2) determination of the doses resulting from different treatment of progeny for exempt values versus the A{sub 1}/A{sub 2} values; and (3) evaluation of the dose justifications for the provisions applicable to exempt materials and low specific activity materials (LSA-I). It was found that the 'previous or intended use' (PIU) provision in Paragraph 107(e) is not risk informed since doses to the most highly exposed persons (e.g., truck drivers) are comparable regardless of intended use of the transported material. The PIU clause can also have important economic implications for co-mined ores and products that are not intended for the fuel cycle but that have uranium extracted as part of their industrial processing. In examination of the footnotes in Table 2 of TS-R-1, which identifies the progeny included in the exempt or A1/A2 values, there is no explanation of how the progeny were selected. It is recommended that the progeny for both the exemption and A{sub 1}/A{sub 2} values should be similar regardless of application, and that the same physical information should be used in deriving the limits. Based on the evaluation of doses due to the transport of low

Aquatic respiration rate measurements at low oxygen concentrations.

Directory of Open Access Journals (Sweden)

Moritz Holtappels

Full Text Available Despite its huge ecological importance, microbial oxygen respiration in pelagic waters is little studied, primarily due to methodological difficulties. Respiration measurements are challenging because of the required high resolution of oxygen concentration measurements. Recent improvements in oxygen sensing techniques bear great potential to overcome these limitations. Here we compare 3 different methods to measure oxygen consumption rates at low oxygen concentrations, utilizing amperometric Clark type sensors (STOX, optical sensors (optodes, and mass spectrometry in combination with (18-18O2 labeling. Oxygen concentrations and consumption rates agreed well between the different methods when applied in the same experimental setting. Oxygen consumption rates between 30 and 400 nmol L(-1 h(-1 were measured with high precision and relative standard errors of less than 3%. Rate detection limits in the range of 1 nmol L(-1 h(-1 were suitable for rate determinations in open ocean water and were lowest at the lowest applied O2 concentration.

Implications of Industrial Processing Strategy on Cellulosic Ethanol Production at High Solids Concentrations

DEFF Research Database (Denmark)

Cannella, David

The production of cellulosic ethanol is a biochemical process of not edible biomasses which contain the cellulose. The process involves the use of enzymes to hydrolyze the cellulose in fermentable sugars to finally produce ethanol via fermentative microorganisms (i.e. yeasts). These biomasses...... are the leftover of agricultural productions (straws), not edible crops (giant reed) or wood, thus the ethanol so produced is also called second generation (or 2G ethanol), which differs from the first generation produced from starch (sugar beets mostly). In the industrial production of cellulosic ethanol high...... solids strategy resulted critical for its cost effectiveness: high concentration of initial biomass it will lead to high concentration of the final product (ethanol), thus more convenient to isolate. This thesis investigate the implementation of a high solids loading concept into cellulosic ethanol...

Risk factors associated with high linezolid trough plasma concentrations.

Science.gov (United States)

Morata, L; De la Calle, C; Gómez-Cerquera, J M; Manzanedo, L; Casals, G; Brunet, M; Cobos-Trigueros, N; Martínez, J A; Mensa, J; Soriano, A

2016-06-01

The major concern of linezolid is the adverse events. High linezolid trough serum concentration (Cmin) has been associated with toxicity. The aim of this study was to analyze factors associated with high Cmin. Main clinical characteristics of 104 patients treated with 600 mg/12 hours of linezolid were retrospectively reviewed. Samples were obtained just before the next dose after at least three doses and within the first 8 days of treatment. High Cmin was considered when it was >8 mg/L. Univariate and multivariate analysis were performed. 34.6% patients had a Cmin >8 mg/L, and they were older and had more frequently an estimated glomerular filtration by MDRD 8 was the renal function. Patients with an eGF 80 mL/min (OR: 4.273) and there was a trend towards a high Cmin in patients with eGF between 40-80 mL/min (OR: 2.109). High Cmin were frequent, especially in patients with MDRD <40 mL/min. Therapeutic drug monitoring could be useful to avoid toxicity in patients with renal dysfunction.

A high-gain, compact, nonimaging concentrator: RXI.

Science.gov (United States)

Miñano, J C; Gonźlez, J C; Benítez, P

1995-12-01

The design procedure of a new nonimaging concentrator (called an RXI) is explained. Rays that impinge on the concentrator aperture, within the acceptance angle, are directed to the receiver by means of one refraction, one reflection, and one total internal reflection. The concentrator can be made as a single dielectric piece (in which the receiver is immersed) whose aspect ratio (thickness/aperture diameter) is close to 1/3. Ray-tracing analysis of a rotational symmetric RXI shows total transmissions of greater than 94.5% (no absorption or reflection losses are considered) when the acceptance angle of the incoming rays is small (<3°) and when the receiver area is the smallest possible (maximal concentration.).

Metal modulation epitaxy growth for extremely high hole concentrations above 1019 cm-3 in GaN

Science.gov (United States)

Namkoong, Gon; Trybus, Elaissa; Lee, Kyung Keun; Moseley, Michael; Doolittle, W. Alan; Look, David C.

2008-10-01

The free hole carriers in GaN have been limited to concentrations in the low 1018cm-3 range due to the deep activation energy, lower solubility, and compensation from defects, therefore, limiting doping efficiency to about 1%. Herein, we report an enhanced doping efficiency up to ˜10% in GaN by a periodic doping, metal modulation epitaxy growth technique. The hole concentrations grown by periodically modulating Ga atoms and Mg dopants were over ˜1.5×1019cm-3.

Investigation on the improved radiation hardness of silicon detectors with high oxygen concentration

CERN Document Server

Moll, Michael; Lindström, G

2000-01-01

We present an investigation on the influence of the oxygen concentration on radiation-induced changes in the effective doping concentration of silicon detectors. Diodes fabricated from silicon with interstitial oxygen content ranging from below 2*10/sup 14/ to 9*10/sup 17/ cm/sup -3/ have been irradiated with fast neutrons up to a fluence of 2*10/sup 15/ cm/sup -2/. Our main interest focused on the so-called stable damage component in the change of the effective doping concentration being of prime importance for the application of silicon detectors in high-energy physics experiments. We demonstrate, that with a high oxygen enrichment the donor removal is appreciably reduced, reaching a value of only 10601130f the initial doping concentration for [O/sub i/]=9*10/sup 17/ cm/sup -3/, while for normal detector grade material with [O/sub i/] below 5*10/sup 16/ cm /sup -3/ that value is 60-90Furthermore, we show that the fluence proportional introduction of stable acceptors is independent of the oxygen concentratio...

The changing trend in nitrate concentrations in major aquifers due to historical nitrate loading from agricultural land across England and Wales from 1925 to 2150

Energy Technology Data Exchange (ETDEWEB)

Wang, L., E-mail: lei.wang@bgs.ac.uk [British Geological Survey, Keyworth, Nottingham NG12 5GG (United Kingdom); Stuart, M.E.; Lewis, M.A. [British Geological Survey, Maclean Building, Wallingford, Oxfordshire OX10 8BB (United Kingdom); Ward, R.S. [British Geological Survey, Keyworth, Nottingham NG12 5GG (United Kingdom); Skirvin, D. [ADAS UK Ltd., Pendeford House, Pendeford Business Park, Wobaston Road, Wolverhampton WV9 5AP (United Kingdom); Naden, P.S. [Centre for Ecology and Hydrology, Maclean Building, Wallingford, Oxfordshire OX10 8BB (United Kingdom); Collins, A.L. [Sustainable Soils and Grassland Systems Department, Rothamsted Research, North Wyke, Okehampton EX20 2SB (United Kingdom); Ascott, M.J. [British Geological Survey, Maclean Building, Wallingford, Oxfordshire OX10 8BB (United Kingdom)

2016-01-15

Nitrate is necessary for agricultural productivity, but can cause considerable problems if released into aquatic systems. Agricultural land is the major source of nitrates in UK groundwater. Due to the long time-lag in the groundwater system, it could take decades for leached nitrate from the soil to discharge into freshwaters. However, this nitrate time-lag has rarely been considered in environmental water management. Against this background, this paper presents an approach to modelling groundwater nitrate at the national scale, to simulate the impacts of historical nitrate loading from agricultural land on the evolution of groundwater nitrate concentrations. An additional process-based component was constructed for the saturated zone of significant aquifers in England and Wales. This uses a simple flow model which requires modelled recharge values, together with published aquifer properties and thickness data. A spatially distributed and temporally variable nitrate input function was also introduced. The sensitivity of parameters was analysed using Monte Carlo simulations. The model was calibrated using national nitrate monitoring data. Time series of annual average nitrate concentrations along with annual spatially distributed nitrate concentration maps from 1925 to 2150 were generated for 28 selected aquifer zones. The results show that 16 aquifer zones have an increasing trend in nitrate concentration, while average nitrate concentrations in the remaining 12 are declining. The results are also indicative of the trend in the flux of groundwater nitrate entering rivers through baseflow. The model thus enables the magnitude and timescale of groundwater nitrate response to be factored into source apportionment tools and to be taken into account alongside current planning of land-management options for reducing nitrate losses. - Highlights: • An approach to modelling groundwater nitrate at the national scale is presented. • The long time-lag for nitrate in the

The changing trend in nitrate concentrations in major aquifers due to historical nitrate loading from agricultural land across England and Wales from 1925 to 2150

International Nuclear Information System (INIS)

Wang, L.; Stuart, M.E.; Lewis, M.A.; Ward, R.S.; Skirvin, D.; Naden, P.S.; Collins, A.L.; Ascott, M.J.

2016-01-01

Nitrate is necessary for agricultural productivity, but can cause considerable problems if released into aquatic systems. Agricultural land is the major source of nitrates in UK groundwater. Due to the long time-lag in the groundwater system, it could take decades for leached nitrate from the soil to discharge into freshwaters. However, this nitrate time-lag has rarely been considered in environmental water management. Against this background, this paper presents an approach to modelling groundwater nitrate at the national scale, to simulate the impacts of historical nitrate loading from agricultural land on the evolution of groundwater nitrate concentrations. An additional process-based component was constructed for the saturated zone of significant aquifers in England and Wales. This uses a simple flow model which requires modelled recharge values, together with published aquifer properties and thickness data. A spatially distributed and temporally variable nitrate input function was also introduced. The sensitivity of parameters was analysed using Monte Carlo simulations. The model was calibrated using national nitrate monitoring data. Time series of annual average nitrate concentrations along with annual spatially distributed nitrate concentration maps from 1925 to 2150 were generated for 28 selected aquifer zones. The results show that 16 aquifer zones have an increasing trend in nitrate concentration, while average nitrate concentrations in the remaining 12 are declining. The results are also indicative of the trend in the flux of groundwater nitrate entering rivers through baseflow. The model thus enables the magnitude and timescale of groundwater nitrate response to be factored into source apportionment tools and to be taken into account alongside current planning of land-management options for reducing nitrate losses. - Highlights: • An approach to modelling groundwater nitrate at the national scale is presented. • The long time-lag for nitrate in the

Effects of combined sewer overflow and stormwater on indicator bacteria concentrations in the Tama River due to the high population density of Tokyo Metropolitan area.

Science.gov (United States)

Ham, Young-Sik; Kobori, Hiromi; Takasago, Masahisa

2009-05-01

The indicator bacteria (standard plate count, total coliform, and fecal coliform bacteria) concentrations have been investigated using six ambient habitats (population density, percent sewer penetration, stream flow rate (m(3)/sec), percent residential area, percent forest area and percent agricultural area) in the Tama River basin in Tokyo, Japan during June 2003 to January 2005. The downstream and tributary Tama River showed higher concentrations of TC and FC bacteria than the upstream waters, which exceeded an environmental quality standard for rivers and a bathing water quality criterion. It was estimated that combined sewer overflow (CSO) and stormwater effluents contributed -4-23% to the indicator bacteria concentrations of the Tama River. The results of multiple regression analyses show that the indicator bacteria concentrations of Tama River basin are significantly affected by population density. It is concluded that the Tama River received a significant bacterial contamination load originating from the anthropogenic source.

Protective effect of high concentrations of vitamin C on the radiation response of Chinese hamster ovary cells

International Nuclear Information System (INIS)

O'Connor, M.K.; Malone, J.F.; Moriarty, M.

1977-01-01

The interaction of radiation with various chemical and physical agents has been studied with a view to finding safe reliable methods of altering radiosensitivity, as well as acquiring a deeper understanding of the chemical and physiological processes involved in the development of radiation damage. The agents most frequently studied include oxygen, known radiosensitisers, metabolic inhibitors and cytotoxic drugs. Because of toxicity, and related problems, manipulation of the concentrations of these substances in vivo is difficult. However many substances, whose importance in normal physiology is well established, have not been well studied from the point of view of their influence on radiation response. The influence of Vitamin C on the survival of mammalian cells (CHO - Clone A) after irradiation is reported. High concentrations of the vitamin (0.3 mg/ml) had a profound effect on radiosensitivity, giving a survival 7 times larger than untreated cells, at the highest dose used. Survival curves demonstrate that the effect is mainly, but not exclusively, due to an increase in the D 0 by a factor of about 1.5. The protective effect occurs in a concentration region that overlaps the physiological range, but the relationship between Vitamin C levels in the cells and in the medium, is complex. These observations could be of importance in reducing biological consequences of accidental radiation exposure, or deliberate diagnostic medical exposures. They may also be important in radiotherapy

A new procedure for estimating the cell temperature of a high concentrator photovoltaic grid connected system based on atmospheric parameters

International Nuclear Information System (INIS)

Fernández, Eduardo F.; Almonacid, Florencia

2015-01-01

Highlights: • Concentrating grid-connected systems are working at maximum power point. • The operating cell temperature is inherently lower than at open circuit. • Two novel methods for estimating the cell temperature are proposed. • Both predict the operating cell temperature from atmospheric parameters. • Experimental results show that both methods perform effectively. - Abstract: The working cell temperature of high concentrator photovoltaic systems is a crucial parameter when analysing their performance and reliability. At the same time, due to the special features of this technology, the direct measurement of the cell temperature is very complex and is usually obtained by using different indirect methods. High concentrator photovoltaic modules in a system are operating at maximum power since they are connected to an inverter. So that, their cell temperature is lower than the cell temperature of a module at open-circuit voltage since an important part of the light power density is converted into electricity. In this paper, a procedure for indirectly estimating the cell temperature of a high concentrator photovoltaic system from atmospheric parameters is addressed. Therefore, this new procedure has the advantage that is valid for estimating the cell temperature of a system at any location of interest if the atmospheric parameters are available. To achieve this goal, two different methods are proposed: one based on simple mathematical relationships and another based on artificial intelligent techniques. Results show that both methods predicts the cell temperature of a module connected to an inverter with a low margin of error with a normalised root mean square error lower or equal than 3.3%, an absolute root mean square error lower or equal than 2 °C, a mean absolute error lower or equal then 1.5 °C, and a mean bias error and a mean relative error almost equal to 0%

Research on high-temperature heat receiver in concentrated solar radiation system

Directory of Open Access Journals (Sweden)

Estera Przenzak

2017-01-01

Full Text Available The article presents the results of experimental and computer simulations studies of the high temperature heat receiver working in the concentrated solar radiation system. In order to study the radiation absorption process and heat exchange, the two types of computer simulations were carried out. The first one was used to find the best location for absorber in the concentrating installation. Ray Tracing Monte Carlo (RTMC method in Trace Pro software was used to perform the optical simulations. The results of these simulations were presented in the form of the solar radiation distribution map and chart. The data obtained in RTMC simulations were used as a second type boundary conditions for Computational Fluid Dynamics (CFD simulations. These studies were used to optimize the internal geometry of the receiver and also to select the most effective flow parameters of the working medium. In order to validate the computer simulations, high temperature heat receiver was tested in experimental conditions. The article presents the results of experimental measurements in the form of temperature, radiation intensity and power graphs. The tests were performed for varied flow rate and receiver location. The experimental and computer simulation studies presented in this article allowed to optimize the configuration of concentrating and heat receiving system.

Generation of high-titer viral preparations by concentration using successive rounds of ultracentrifugation

Directory of Open Access Journals (Sweden)

Ichim Christine V

2011-08-01

Full Text Available Abstract Background Viral vectors provide a method of stably introducing exogenous DNA into cells that are not easily transfectable allowing for the ectopic expression or silencing of genes for therapeutic or experimental purposes. However, some cell types, in particular bone marrow cells, dendritic cells and neurons are difficult to transduce with viral vectors. Successful transduction of such cells requires preparation of highly concentrated viral stocks, which permit a high virus concentration and multiplicity of infection (MOI during transduction. Pseudotyping with the vesicular stomatitis virus G (VSV-G envelope protein is common practice for both lentiviral and retroviral vectors. The VSV-G glycoprotein adds physical stability to retroviral particles, allowing concentration of virus by high-speed ultracentrifugation. Here we describe a method report for concentration of virus from large volumes of culture supernatant by means of successive rounds of ultracentrifugation into the same ultracentrifuge tube. Method Stable retrovirus producer cell lines were generated and large volumes of virus-containing supernatant were produced. We then tested the transduction ability of virus following varying rounds of concentration by ultra-centrifugation. In a second series of experiments lentivirus-containing supernatant was produced by transient transfection of 297T/17 cells and again we tested the transduction ability of virus following multiple rounds of ultra-centrifugation. Results We report being able to centrifuge VSV-G coated retrovirus for as many as four rounds of ultracentrifugation while observing an additive increase in viral titer. Even after four rounds of ultracentrifugation we did not reach a plateau in viral titer relative to viral supernatant concentrated to indicate that we had reached the maximum tolerated centrifugation time, implying that it may be possible to centrifuge VSV-G coated retrovirus even further should it be necessary

Leaching of copper concentrates with high arsenic content in chlorine-chloride media

International Nuclear Information System (INIS)

Herreros, O.; Fuentes, G.; Quiroz, R.; Vinals, J.

2003-01-01

This work reports the results of copper concentrates leaching which have high arsenic concepts (up to 2.5%). The treatments were carried out using chlorine that forms from sodium hypochlorite and sulphuric acid. The aim of this work is to obtain a solution having high copper content 4 to 6 g/l and 5 to 7 g/l free acid in order to submit it directly to a solvent extraction stage. In addition, this solution should have minimum content of arsenic and chloride ions. To carry out this investigation, an acrylic reactor was constructed where the leaching tests were made at constant temperature in a thermostatic bath under atmospheric pressure. The concentrate samples were obtained from mineral processing plants from Antofagasta, Chile. Typical variables were studied, such as leaching agent concentration, leaching time, pulp density and temperature among others. Some of the residues were analyzed by XRD and EPS. On the other hand, the solutions were analyzed by Atomic Absorption Spectroscopy. The results indicate solutions having the contents stated above can be obtained. (Author) 19 refs

Activity concentration and population dose from natural occurring radionuclide (40K) due to consumption of fresh water fish

International Nuclear Information System (INIS)

Jha, M.K.; Patra, A.K.; Jaison, T.J.; Ravi, P.M.; Tripathi, R.M.

2015-01-01

The objective of this study was to measure the concentration of natural occurring radionuclide ( 40 K) in different fresh water fish collected from Moticher lake near Kakrapar, Gujarat. The three types of commonly available fresh water fish in Moticher lake are Notopterus sps, Ophiocephalus sps. and Tor sps. The 40 K activity (Bq/kg flesh wt.) was found to be in the range of 38-100 (Notopterus sps.), 33-123 (Ophiocephalus sps.) and 80-116 (Tor sps.) respectively. The ingestion dose (μSv/y) to the adult population around Kakrapar was estimated due to the consumption of fresh water fish and found to be in the range of 7.7-20.5 (Notopterus sps.), 6.8-25.0 (Ophiocephalus sps.) and 16.0-24.0 (Tor sps.) respectively. (author)

Liver imaging with MDCT and high concentration contrast media

International Nuclear Information System (INIS)

Spielmann, Audrey L.

2003-01-01

Liver imaging has advanced greatly over the last 10 years with helical CT capability and more recently the addition of multidetector-row CT (MDCT). Multidetector CT technology facilitates imaging at faster speeds with improved image quality and less breathing artifact [Abdom. Imaging 25 (2000) 643]. Exquisite three-dimensional data sets can be obtained with thin collimation providing improved lesion detection, multiplanar imaging, and the ability to perform CT angiography of the liver and mesenteric vessels. New challenges arise with this advance in technology including safety considerations. The radiation dose to the patient has increased with MDCT and this is compounded by the ability to perform multi-phase liver imaging. Furthermore, issues of contrast media administration require reconsideration including optimal timing and rate of administration, the total volume of contrast needed and the ideal iodine concentration of the contrast media. Recently, the use of high concentration contrast media (HCCM) has been explored and study results to date will be reviewed

pH-Dependent Toxicity of High Aspect Ratio ZnO Nanowires in Macrophages Due to Intracellular Dissolution

KAUST Repository

H. Müller, Karin

2010-11-23

High-aspect ratio ZnO nanowires have become one of the most promising products in the nanosciences within the past few years with a multitude of applications at the interface of optics and electronics. The interaction of zinc with cells and organisms is complex, with both deficiency and excess causing severe effects. The emerging significance of zinc for many cellular processes makes it imperative to investigate the biological safety of ZnO nanowires in order to guarantee their safe economic exploitation. In this study, ZnO nanowires were found to be toxic to human monocyte macrophages (HMMs) at similar concentrations as ZnCl2. Confocal microscopy on live cells confirmed a rise in intracellular Zn2+ concentrations prior to cell death. In vitro, ZnO nanowires dissolved very rapidly in a simulated body fluid of lysosomal pH, whereas they were comparatively stable at extracellular pH. Bright-field transmission electron microscopy (TEM) showed a rapid macrophage uptake of ZnO nanowire aggregates by phagocytosis. Nanowire dissolution occurred within membrane-bound compartments, triggered by the acidic pH of the lysosomes. ZnO nanowire dissolution was confirmed by scanning electron microscopy/energy-dispersive X-ray spectrometry. Deposition of electron-dense material throughout the ZnO nanowire structures observed by TEM could indicate adsorption of cellular components onto the wires or localized zinc-induced protein precipitation. Our study demonstrates that ZnO nanowire toxicity in HMMs is due to pH-triggered, intracellular release of ionic Zn2+ rather than the high-aspect nature of the wires. Cell death had features of necrosis as well as apoptosis, with mitochondria displaying severe structural changes. The implications of these findings for the application of ZnO nanowires are discussed. © 2010 American Chemical Society.

An assessment of a spiral duct centrifuge using standard and high concentration aerosols

International Nuclear Information System (INIS)

Smith, A.D.

1982-12-01

The Stoeber spiral duct centrifuge has been calibrated by means of polystyrene latex microspheres for the subsequent measurement of aerosol particle size distributions. Intermediate (1 g m -3 ) ad high (100 g m -3 ) sodium chloride aerosol concentrations have been sampled by the centrifuge to determine possible limitations in the equipment. Corrections have to be made for the effect of Coriolis forces, and aerosol concentrations above 1 g m -3 should be diluted before sampling. The spiral duct centrifuge is an extremely versatile instrument for aerosol analysis, and shows a high degree of reliability when operated under well-defined conditions. (author)

High plant uptake of radiocesium from organic soils due to Cs mobility and low soil K content

International Nuclear Information System (INIS)

Sanchez, A.L.; Wright, S.M.; Naylor, C.; Kennedy, V.H.; Dodd, B.A.; Singleton, D.L.; Barnett, C.L.; Stevens, P.A.

1999-01-01

Post-Chernobyl experience has demonstrated that persistently high plant transfer of 137 Cs occurs from organic soils in upland and seminatural ecosystems. The soil properties influencing this transfer have been known for some time but have not been quantified. A pot experiment was conducted using 23 soils collected from selected areas of Great Britain, which were spiked with 134 Cs, and Agrostis capillaris grown for 19--45 days. The plant-to-soil 134 Cs concentration ratio (CR) varied from 0.06 to 44; log CR positively correlated to soil organic matter content (R 2 = 0.84), and CR values were highest for soils with low distribution coefficients (K d ) of 134 Cs. Soils with high organic matter contents and high concentrations of NH 4 + in solution showed high 134 Cs mobility (low K d ). The plant-to-soil solution 134 Cs ratio decreased sharply with increasing soil solution K + . A two parameter linear model, used to predict log CR from soil solution K + and K d , explained 94% of the variability in CR values. In conclusion, the high transfer of 134 Cs in organic soils is related to both the high 134 Cs mobility (low clay content and high NH 4 + concentrations) and low K availability

Natural radioactivity concentration in raw materials used for manufacturing refractory products

International Nuclear Information System (INIS)

Fathivand, A. A.; Amidi, J.; Hafezi, S.

2007-01-01

Some Particular areas contain natural radionuclide at levels much higher than those usually present in earth's crust. The radiological impact of the use of zirconium ore in zirconium industry is due to internal exposure of the lung by alpha particles and external exposure of the body by the gamma rays. The result of gamma spectrometry measurement of the concentrations of the natural radionuclide in zirconium industry is described. Materials and Methods: Gamma spectrometry system with a shielded high pure germanium (HPGe) detector connected to multi channel analyzer (MCA) was used to determine concentrations of natural radionuclide in about 45 samples of imported zirconium minerals, tiles, stone ware and waste sludge's of Iranian ceramic industry. Results: The 238 U concentration in the samples, ranging from 3000 to 10000 Bq Kg -1 , is higher than the concentration of both 232 Th (500-1800 Bq Kg -1 ), and 40 K (50-800 Bq Kg -1 ). The measured specific activities in the mineral showed that specific activity of baddeleyite is higher than that of zircon. The results of ceramic tiles show that the tiles usually contain small amount of zirconium compound. Conclusion: Due to relatively high concentration level of uranium in imported zirconium samples, specific regulations is necessary for zirconium compound used in ceramic industry

Mineral water 222 Rn activity decrease due to consumption habits

International Nuclear Information System (INIS)

Cipriani, Moacir; Taddei, Maria Helena Tirollo; Silva, Nivaldo Carlos da

2001-01-01

Mineral waters from the Pocos de Caldas Plateau springs, an elevated region with high natural radioactivity, in the State of Minas Gerais, Brazil, have significant 222 Rn concentration on site. The highest concentration in the waters are from: Fonte Villela - Aguas da Prata (∼ 1000 Bql -1 ); Fonte Grande Hotel - Pocinhos do Rio Verde (∼ 400 Brq -1 ) and Fonte CNEN Lab - Pocos de Caldas (∼ 290 Bql -1 ). These waters are used by the population as drinking water and due to consumption habits, can lead to internal doses above accepted limits for the public. This work deals with the decrease of 222 Rn activity in mineral waters fro two different popular consumption habits, and with the adult effective dose equivalent reduction due to water consumption habits. It has been found that the estimated dose based on the biokinetic Crawford-Brown model, can be one fourth of dose based on 222 Rn activity on site. (author)

Exploring the uncertainty in attributing sediment contributions in fingerprinting studies due to uncertainty in determining element concentrations in source areas.

Science.gov (United States)

Gomez, Jose Alfonso; Owens, Phillip N.; Koiter, Alex J.; Lobb, David

2016-04-01

One of the major sources of uncertainty in attributing sediment sources in fingerprinting studies is the uncertainty in determining the concentrations of the elements used in the mixing model due to the variability of the concentrations of these elements in the source materials (e.g., Kraushaar et al., 2015). The uncertainty in determining the "true" concentration of a given element in each one of the source areas depends on several factors, among them the spatial variability of that element, the sampling procedure and sampling density. Researchers have limited control over these factors, and usually sampling density tends to be sparse, limited by time and the resources available. Monte Carlo analysis has been used regularly in fingerprinting studies to explore the probable solutions within the measured variability of the elements in the source areas, providing an appraisal of the probability of the different solutions (e.g., Collins et al., 2012). This problem can be considered analogous to the propagation of uncertainty in hydrologic models due to uncertainty in the determination of the values of the model parameters, and there are many examples of Monte Carlo analysis of this uncertainty (e.g., Freeze, 1980; Gómez et al., 2001). Some of these model analyses rely on the simulation of "virtual" situations that were calibrated from parameter values found in the literature, with the purpose of providing insight about the response of the model to different configurations of input parameters. This approach - evaluating the answer for a "virtual" problem whose solution could be known in advance - might be useful in evaluating the propagation of uncertainty in mixing models in sediment fingerprinting studies. In this communication, we present the preliminary results of an on-going study evaluating the effect of variability of element concentrations in source materials, sampling density, and the number of elements included in the mixing models. For this study a virtual

Metal modulation epitaxy growth for extremely high hole concentrations above 1019 cm-3 in GaN

International Nuclear Information System (INIS)

Namkoong, Gon; Trybus, Elaissa; Lee, Kyung Keun; Moseley, Michael; Doolittle, W. Alan; Look, David C.

2008-01-01

The free hole carriers in GaN have been limited to concentrations in the low 10 18 cm -3 range due to the deep activation energy, lower solubility, and compensation from defects, therefore, limiting doping efficiency to about 1%. Herein, we report an enhanced doping efficiency up to ∼10% in GaN by a periodic doping, metal modulation epitaxy growth technique. The hole concentrations grown by periodically modulating Ga atoms and Mg dopants were over ∼1.5x10 19 cm -3

Potential high temperature corrosion problems due to co-firing of biomass and fossil fuels

DEFF Research Database (Denmark)

Montgomery, Melanie; Vilhelmsen, T.; Jensen, S.A.

2007-01-01

Over the past years, considerable high temperature corrosion problems have been encountered when firing biomass in power plants due to the high content of potassium chloride in the deposits. Therefore to combat chloride corrosion problems co-firing of biomass with a fossil fuel has been undertaken....... This results in potassium chloride being converted to potassium sulphate in the combustion chamber and it is sulphate rich deposits that are deposited on the vulnerable metallic surfaces such as high temperature superheaters. Although this removes the problem of chloride corrosion, other corrosion mechanisms...... appear such as sulphidation and hot corrosion due to sulphate deposits. At Studstrup power plant Unit 4, based on trials with exposure times of 3000 hours using 0-20% straw co-firing with coal, the plant now runs with a fuel of 10% straw + coal. After three years exposure in this environment...

Influence of air mass origins on optical properties and PM concentrations measured at a high mountain station located in the southwestern Mediterranean

Science.gov (United States)

Castañer, R.; Nicolás, J. F.; Crespo, J.; Yubero, E.; Galindo, N.; Caballero, S.; Pastor, C.

2017-11-01

The influence of air mass origins on aerosol optical properties and particulate matter (PM) concentrations measured from January 2014 to December 2015 at a high mountain station in the southwestern Mediterranean was analyzed. Mean values of extensive aerosol optical properties (scattering, backscattering and absorption coefficients) and PM mass fractions: σsp (30.7 ± 1.1 Mm- 1), σbsp (3.9 ± 0.1 Mm- 1), σap (2.4 ± 0.1 Mm- 1), PM10 (13.1 ± 0.6 μg·m- 3) and PM1 (4.0 ± 0.1 μg·m- 3) were in the range of values reported in most studies carried out at high altitude locations. Nevertheless, a significant variation of these concentrations according to the air mass origin has been noticed. Transport from North Africa (NAF back-trajectories) and regional recirculations (REG) were the two air mass types in which the highest values of PM concentrations and optical properties were registered. Alternatively, the lowest values were recorded under Atlantic advections. Noticeable differences between NAF and REG categories were observed when intensive optical properties of aerosols were analyzed. During NAF scenarios the lowest value of SAE (0.91 ± 0.06) was obtained as well as the greatest AAE value (1.30 ± 0.02), with daily levels higher than 1.90. This result suggests that OC and hematite compounds were relevant in the absorption process during NAF events. However, during REG episodes the AAE mean value declined to 1.18 ± 0.01, since the highest mean concentration of BC was recorded under this category, and the SAE value was maximum (1.70 ± 0.05) due to the smaller size of PM. It has also been documented that during the study period a great number of REG back-trajectories occurred just after the transport of air masses from North Africa. In these situations, AAE and SAE values showed slight variations due to the persistence of mineral dust in the local atmosphere.

A point focusing double parabolic trough concentrator

Energy Technology Data Exchange (ETDEWEB)

Murphree, Quincy C. [Kentucky Mountain Bible College, Vancleve, KY (United States)

2001-07-01

This article shows that a point focusing solar concentrator can be made from two reflective parabolic troughs, a primary and a secondary, by orienting their longitudinal axes in perpendicular directions and separating them by the difference of their focal lengths along the optical axis. This offers a new alternative to the conventional 3-D paraboloidal concentrator permitting more flexibility in designs for applications requiring high concentrations. Both advantages and disadvantages are discussed. The intensity concentration ratio distribution is calculated in the focal plane and has elliptically shaped contours due to the inherent compensation of errant rays by the concave secondary. The ratio of the major to minor axes was 2.61 for the case considered, resulting in a concentration {approx}2.61 times that of a comparable concentrator without the compensation afforded by a concave secondary. Still, geometrical constraints limit the concentration to about 2000 suns for mirror quality errors of 5 mr. Optimisation of the compensation effect holds potential for improved performance for other concentrator designs. Finally, the functional dependence of the peak concentration and shading factor upon design parameters are presented. (Author)

Activity concentration and AACED due to 40K in some selected medicinal plants

International Nuclear Information System (INIS)

Chandrashekara, K.; Radhakrishna, A.P.; Somashekarappa, H.M.

2017-01-01

The activity concentrations in soil and medicinal plants, soil to plant transfer factors (TF), and Average Annual Committed Effective Dose (AACED) of 40 K in prominent medicinal plants of Malnad Kerala were estimated. The range of activity concentrations were 144.15 - 558.99 and 405.87 - 2990.75 Bq kg -1 in soil and medicinal plants respectively. The TF was found to vary from 2.34 to 14.84, whereas AACED varied in the range 2.51 - 18.54 mSv y -1 . The study may help to form the database and safety regulations connected with 40 K activity in medicinal plants. (author)

High-voltage electrical burns due to copper theft – Case series

Science.gov (United States)

Braga, M.J.; Oliveira, I.; Egipto, P.; Silva, A.

2016-01-01

Summary Electrical burns are among the most devastating trauma inflicted on the human body. These burns have a higher morbidity, length of stay and a much higher risk of amputation than any other type of burn. Electrical burns affect mostly young, working males because they are more frequently the result of a work accident. However, possibly due to the worldwide economic crisis, we are experiencing a new phenomenon: the theft of high-voltage copper wiring. PMID:27857650

Increased serum C-reactive protein concentrations in dogs with congestive heart failure due to myxomatous mitral valve disease

DEFF Research Database (Denmark)

Reimann, M. J.; Ljungvall, I.; Hillstrom, A.

2016-01-01

Cardiovascular disease in humans and dogs is associated with mildly increased circulating concentrations of C-reactive protein (CRP). Few studies have evaluated associations between circulating CRP and canine myxomatous mitral valve disease (MMVD) and the results reported have been divergent....... The aim of this study was to investigate whether serum concentrations of CRP, determined using a novel automated canine-specific high -sensitivity CRP assay (Gentian hsCRP), were associated with severity of MMVD and selected clinical variables in dogs. The study included 188 client-owned dogs...... with different severities of MMVD. Dogs were classified based on ACVIM consensus statement guidelines (group A, n = 58; group BI, n = 56; group B2, n = 38; group C, n = 36). Data were analysed using descriptive statistics and multiple regression analysis. Dogs with congestive heart failure (CHF; group C) had...

Potential high temperature corrosion problems due to co-firing of biomass and fossil fuels

DEFF Research Database (Denmark)

Montgomery, Melanie; Vilhelmsen, T.; Jensen, S.A.

2008-01-01

Over the past few years, considerable high temperature corrosion problems have been encountered when firing biomass in power plants due to the high content of potassium chloride in the deposits. Therefore, to combat chloride corrosion problems cofiring of biomass with a fossil fuel has been...... undertaken. This results in potassium chloride being converted to potassium sulphate in the combustion chamber and it is sulphate rich deposits that are deposited on the vulnerable metallic surfaces such as high temperature superheaters. Although this removes the problem of chloride corrosion, other...... corrosion mechanisms appear such as sulphidation and hot corrosion due to sulphate deposits. At Studstrup power plant Unit 4, based on trials with exposure times of 3000 h using 0–20% straw co-firing with coal, the plant now runs with a fuel mix of 10% strawþcoal. Based on results from a 3 years exposure...

Carrier concentration induced ferromagnetism in semiconductors

International Nuclear Information System (INIS)

Story, T.

2007-01-01

In semiconductor spintronics the key materials issue concerns ferromagnetic semiconductors that would, in particular, permit an integration (in a single multilayer heterostructure) of standard electronic functions of semiconductors with magnetic memory function. Although classical semiconductor materials, such as Si or GaAs, are nonmagnetic, upon substitutional incorporation of magnetic ions (typically of a few atomic percents of Mn 2+ ions) and very heavy doping with conducting carriers (at the level of 10 20 - 10 21 cm -3 ) a ferromagnetic transition can be induced in such diluted magnetic semiconductors (also known as semimagnetic semiconductors). In the lecture the spectacular experimental observations of carrier concentration induced ferromagnetism will be discussed for three model semiconductor crystals. p - Ga 1-x Mn x As currently the most actively studied and most perspective ferromagnetic semiconductor of III-V group, in which ferromagnetism appears due to Mn ions providing both local magnetic moments and acting as acceptor centers. p - Sn 1-x Mn x Te and p - Ge 1-x Mn x Te classical diluted magnetic semiconductors of IV-VI group, in which paramagnet-ferromagnet and ferromagnet-spin glass transitions are found for very high hole concentration. n - Eu 1-x Gd x Te mixed magnetic crystals, in which the substitution of Gd 3+ ions for Eu 2+ ions creates very high electron concentration and transforms antiferromagnetic EuTe (insulating compound) into ferromagnetic n-type semiconductor alloy. For each of these materials systems the key physical features will be discussed concerning: local magnetic moments formation, magnetic phase diagram as a function of magnetic ions and carrier concentration as well as Curie temperature and magnetic anisotropy engineering. Various theoretical models proposed to explain the effect of carrier concentration induced ferromagnetism in semiconductors will be briefly discussed involving mean field approaches based on Zener and RKKY

High efficiency detection technique on quantum action due to radiation excitation

International Nuclear Information System (INIS)

Yamazaki, Tetsuo; Kobayashi, Naoto; Sakamoto, Isao; Hayashi, Nobuyuki; Okubo, Masataka

1999-01-01

For a key point to obtain high energy resolution, three items such as long life of quasi particle, short tunneling time, and low leakage current can be shown. Then, in order to establish high energy resolution by filling these three items, a research on Nb/Al/AlO x /Al/Nb superconducting tunnel junction was proceeded. In 1997 fiscal year, elucidation on phonon relaxation phenomenon in Nb crystal grain boundary was conducted. On energy resolution, by realizing increase of quasi particle life and upgrading if junction quality, 70 to 90 eV which is higher than that of semiconductor detector could be established. After then, to remove the phonon relaxation at crystal grain boundary, it was necessary to practise high qualification of absorber such as improvement of Nb film micro structure and single crystallization, and enforcement of quasi particle trapping due to superconductor except Nb/Al. (G.K.)

Highly Concentrated Acetic Acid Poisoning: 400 Cases Reviewed

Directory of Open Access Journals (Sweden)

Konstantin Brusin

2012-12-01

Full Text Available Background: Caustic substance ingestion is known for causing a wide array of gastrointestinal and systemic complications. In Russia, ingestion of acetic acid is a major problem which annually affects 11.2 per 100,000 individuals. The objective of this study was to report and analyze main complications and outcomes of patients with 70% concentrated acetic acid poisoning. Methods: This was a retrospective study of patients with acetic acid ingestion who were treated at Sverdlovsk Regional Poisoning Treatment Center during 2006 to 2012. GI mucosal injury of each patient was assessed with endoscopy according to Zargar’s scale. Data analysis was performed to analyze the predictors of stricture formation and mortality. Results: A total of 400 patients with median age of 47 yr were included. GI injury grade I was found in 66 cases (16.5%, IIa in 117 (29.3%, IIb in 120 (30%, IIIa in 27 (16.7% and IIIb in 70 (17.5%. 11% of patients developed strictures and overall mortality rate was 21%. Main complications were hemolysis (55%, renal injury (35%, pneumonia (27% and bleeding during the first 3 days (27%. Predictors of mortality were age 60 to 79 years, grade IIIa and IIIb of GI injury, pneumonia, stages “I”, “F” and “L” of kidney damage according to the RIFLE scale and administration of prednisolone. Predictors of stricture formation were ingestion of over 100 mL of acetic acid and grade IIb and IIIa of GI injury. Conclusion: Highly concentrated acetic acid is still frequently ingested in Russia with a high mortality rate. Patients with higher grades of GI injury, pneumonia, renal injury and higher amount of acid ingested should be more carefully monitored as they are more susceptible to develop fatal consequences.          

Cation effect on small phosphonium based ionic liquid electrolytes with high concentrations of lithium salt

Science.gov (United States)

Chen, Fangfang; Kerr, Robert; Forsyth, Maria

2018-05-01

Ionic liquid electrolytes with high alkali salt concentrations have displayed some excellent electrochemical properties, thus opening up the field for further improvements to liquid electrolytes for lithium or sodium batteries. Fundamental computational investigations into these high concentration systems are required in order to gain a better understanding of these systems, yet they remain lacking. Small phosphonium-based ionic liquids with high concentrations of alkali metal ions have recently shown many promising results in experimental studies, thereby prompting us to conduct further theoretical exploration of these materials. Here, we conducted a molecular dynamics simulation on four small phosphonium-based ionic liquids with 50 mol. % LiFSI salt, focusing on the effect of cation structure on local structuring and ion diffusional and rotational dynamics—which are closely related to the electrochemical properties of these materials.

Is the High Cu Tolerance of Trichoderma atroviride Isolated from the Cu-Polluted Sediment Due to Adaptation? An In Vitro Toxicological Study

International Nuclear Information System (INIS)

Yap, C.K.; Yazdani, M.; Abdullah, F.; Tan, S.G.

2011-01-01

The tolerance of Cu by Trichoderma atroviride, a tolerant fungus isolated from the drainage surface sediment of the Serdang Industrial Area was investigated under in vitro conditions. Only this fungus species can tolerate up to 600 mg/ L of Cu on solid medium Potato Dextrose Agar based on the isolation of the most tolerant fungus from the polluted sediment. Toxicity test performed on T. atroviride, showed a maximum tolerance at 300 mg/L of Cu concentration when grown in liquid medium Potato Dextrose Broth (PDB). The EC 50 value of the isolate was 287.73 mg/ L of Cu concentration in PDB. The Cu concentration in the drainage surface sediment, where the T. atroviride was isolated from, was 347.64 μg/ g while the geochemical distributions of the non-resistant and resistant fractions of Cu were 99.6 and 0.4 %, respectively. The sediment data indicated that the drainage had greatly received anthropogenic Cu from the nearby industries which are involved in the manufacturing of plastics and electronic products. The present findings indicate that the high Cu tolerance showed by T. atroviride could be due to the well adaptation of the fungus to the Cu polluted sediment. Therefore, T. atroviride could be a potential bioremediator of Cu pollution in the freshwater ecosystem. (author)

Damage of plants due to peroxyacyl nitrates (PAN)

Energy Technology Data Exchange (ETDEWEB)

Fukuda, H.; Terakado, K.

1974-02-01

In Japan plant damages began to resemble those due to PAN about 1972. Exposure experiments with artifically synthesized PAN in an environment simulation room determined the concentration of PAN and its duration to examine the relationship between these data in the field and crop damage. Synthesized PAN created by irradiating a mixture of ethyl nitrate and oxygen with ultraviolet light gave results similar to those seen in fields. From the end of April to the end of November, damages to petunias seemingly due to PAN appeared 15 times. The symptoms differed with the variety of petunia. After 14 experiments in fields from September 20 to November 30 with a continuous determination of the environmental concentration of PAN, damages to petunia were confirmed on 6 days when the maximum PAN concentration range was 3.0-6.7 ppb. The duration of concentrations higher than 3 ppb was 2-13 hr. The most serious damage appeared on September 20 when a concentration of more than 5 ppb continued for 7 hours. No damage appeared with a long continuation (6-12 hr) of a lower concentration of PAN of 2 ppb. Inter-varietal grafting showed that the symptoms and the degree of damage due to PAN were influenced only by the physiological specificity of the aerial portion of the plant. Leaves which are most affected by PAN differed with the variety of petunia.

Traceable measurements of the activity concentration in air

International Nuclear Information System (INIS)

Paul, Annette; Honig, Anja; Forkel-Wirth, Doris; Mueller, Andre; Marcos, Alicia

2002-01-01

The nuclear reactions induced by high energetic protons in heavy targets such as UC 2 and ThC cause a particular, complex radiation protection task at facilities like ISOLDE: the measurement of a mixture of different isotopes of the radioactive noble gas radon and the radon progenies in air. The knowledge of their respective activity concentration is fundamental for exposure assessments. Due to the complex mixture of activity concentrations in air, its precise determination is quite difficult. Therefore, a new procedure for taking reference samples was developed and implemented for the traceable measurement of the activity concentration of radioactive ions (e.g., radon progenies) in air. This technique is combined by measuring α-particles with a multi-wire ionization chamber for the parallel on-line determination of the activity concentration of different radon isotopes

Stationary nonimaging concentrator as a second stage element in tracking systems

Energy Technology Data Exchange (ETDEWEB)

Kritchman, E.M.; O' Gallagher, J.; Snail, K.A.; Winston, R.

1983-06-01

The University of Chicago solar energy group and GTE Research have developed an Integrated Stationary Evacuated Concentration (ISEC) collector tube. In this paper the increase in concentration of line focus concentrators that can be achieved using the evacuated CPC collector tube as a second stage element is examined. Three primary elements of the overall concentration are analyzed: a flat parabolic absorber trough, a flat Fresnel lens, and a color and coma corrected Fresnel lens. The three examples demonstrate that high concentration ratios may be achieved by using the already fabricated ISEC as a second stage element. The ISEC also suppresses thermal losses due to conduction, convection, and infrared radiation.

High fetal plasma adenosine concentration: a role for the fetus in preeclampsia?

LENUS (Irish Health Repository)

Espinoza, Jimmy

2012-02-01

OBJECTIVE: Clinical observations suggest a role for the fetus in the maternal manifestations of preeclampsia, but the possible signaling mechanisms remain unclear. This study compares the fetal plasma concentrations of adenosine from normal pregnancies with those from preeclampsia. STUDY DESIGN: This secondary data analysis included normal pregnancies (n = 27) and patients with preeclampsia (n = 39). Patients with preeclampsia were subclassified into patients with (n = 25) and without (n = 14) abnormal uterine artery Doppler velocimetry (UADV). RESULTS: Fetal plasma concentrations of adenosine were significantly higher in patients with preeclampsia (1.35 +\\/- 0.09 mumol\\/L) than in normal pregnancies (0.52 +\\/- 0.06 mumol\\/L; P < .0001). Fetal plasma concentrations of adenosine in patients with preeclampsia with abnormal UADV (1.78 +\\/- 0.15 mumol\\/L), but not with normal UADV (0.58 +\\/- 0.14 mumol\\/L), were significantly higher than in normal pregnancies (P < .0001). CONCLUSION: Patients with preeclampsia with sonographic evidence of chronic uteroplacental ischemia have high fetal plasma concentrations of adenosine.

SOIL N, P AND K CONCENTRATIONS AND RICE YIELD INCREASED DUE TO THE APPLICATION OF Azolla pinnata

Directory of Open Access Journals (Sweden)

A. Arivin Rivaie*

2014-01-01

Full Text Available Many studies showed that application of Azolla pinnata as biofertilizer improved soil fertility some agricultural crops, including rice, whereas farmers in Lampung consider that A. pinnata suppresses growth of rice seedlings, so they throw it field by raising irrigation water surface. Information on effects A. pinnata application on changes in nutrient availability and rice yield obtained from paddy fields of regions still rare. A study was carried out to investigate effects of different rates of A. pinnata on changes in N, P, K concentrations in paddy soils, N uptake, and rice yield. A well-irrigated paddy field was incorporated with A. pinnata, and then rice seedlings of Ciherang variety had been grown from June up to December 2009. Results: application of A. pinnata at dose of five t per ha increased concentration of N, P and K as well as rice yield. A. pinnata had a relatively high N content, ie 2.43 percent. Application of A. pinnata of 7.5 t per ha increased significantly available soil P, indicated that A. pinnata requires a fairly high P to grow optimally. Application of A. pinnata of 7.5 t per ha gave highest dry grain yield, suggests that application A. pinnata did not suppress rice yield, even use of A. pinnata as organic matter source will help to conserve fossil fuels and foreign exchange as well as will allow more paddy fields that can be fertilized by N.

Radon in houses due to radon in potable water

International Nuclear Information System (INIS)

Hess, C.T.; Korsah, J.K.; Einloth, C.J.

1987-01-01

Radon concentration in the air of 10 houses has been measured as a function of water use and meterological parameters such as barometric pressure, wind velocity and direction, indoor and outdoor temperature, and rainfall. Results of calibrations and data collected in winter, spring, fall, and summer are given for selected houses. Average values of radon concentration in air are from 0.80 to 77 rhoCi/1. Water use average ranges from 70 to 240 gal/day. Average potential alpha energy concentrations in these houses range from 0.02 to 1.6 working levels. The radon level due to water use ranges from 0 to 36% of the house radon from soil and water combined. The radon level change due to use of a filter on the water supply shows a 60% reduction in radon in the house. Conclusions are that water radon can be a major fraction of the radon in houses. The ratio of airborne radon concentration due to water use to the radon concentration in water is 4.5 x 10/sup -5/ - 13 x 10/sup -5/

Live changes in muscle glycogen concentration of steers due to feeding and fasting as determined through serial biopsies of the Longissimus dorsi muscle

Directory of Open Access Journals (Sweden)

Ariel Apaoblaza

2014-03-01

Full Text Available Insufficient glycogen content in bovine muscle at slaughter produces meat with high final pH (> 5.8 which is undesirable. The objective of this study was to determine through biopsies the live changes in muscle glycogen concentration (MGC of housed steers fed on hay or hay plus energy concentrate for 30 d and then determine the effect of food deprivation (fasting for 24 h on the same variable. Ten steers of similar age, weight, and phenotypic characteristics were housed in individual pens and randomly assigned to two feeding treatments: ad libitum hay only (H, n = 5 and ad libitum hay plus flaked corn (Zea mays L. (HC, n = 5. Biopsies (B were taken from the Longissimus dorsi muscle at four occasions: the day before the start of experiment (B0, after 15 d (Bl, after 30 d (B2, and fasted for 24 h after B2 (B3. Before each biopsy, steers were sedated with xylazine (0.03 mL kg-1 and lidocaine was applied locally; samples were frozen in liquid nitrogen to determine MGC. Results showed a significant (P H and also of time (B2 > Bl on MGC; the decrease in MGC of steers due to fasting (B2 vs. B3 was not significant (P > 0.05. It was concluded that muscle biopsies allowed to detect a difference in the increase of MGC in steers fed an energy supplementation compared to steers fed hay only, and that fasting for 24 h tended to reduce MGC in both groups.

OZONE CONCENTRATION ATTRIBUTABLE PREMATURE DEATH IN POLAND

Directory of Open Access Journals (Sweden)

Krzysztof Skotak

2010-03-01

Full Text Available Ozone in the lower part of the atmosphere (troposphere, strong photochemical oxidant, is not directly emitted to the atmosphere but formed through a series of complex reactions. Ozone concentrations depends on ozone precursors air contamination (mainly nitrogen dioxide and non-methane volatile organic compounds and meteorological conditions (temperature and solar radiation. The main sectors emitted ozone precursors are road transport, power and heat generation plants, household (heating, industry, and petrol storage and distribution. Ozone and some of its precursors are also transported long distances in the atmosphere and are therefore considered a transboundary problem. As a result, the ozone concentrations are often low in busy urban areas and higher in suburban and rural areas. Nowadays, instead of particulate matter, ozone is one of the most widespread global air pollution problems. In and around urban areas, relatively large gradients of ozone can be observed. Because of its high reactivity in elevated concentrations ozone causes serious health problems and damage to ecosystems, agricultural crops and materials. Main ill-health endpoints as a results of ozone concentrations can be characterised as an effect of pulmonary and cardiovascular system, time morbidity and mortality series, development of atherosclerosis and asthma and finally reduction in life expectancy. The associations with increased daily mortality due to ozone concentrations are confirmed by many researches and epidemiological studies. Estimation of the level selected ill-health endpoints (mortality in total and due to cardiovascular and respiratory causes as a result of the short-term ozone exposure in Poland was the main aim of the project. Final results have been done based on estimation method elaborated by WHO, ozone measurements from National Air Quality Monitoring System and statistical information such as mortality rate and populations. All analysis have been done in

Effects of meals rich in either monounsaturated or saturated fat on lipid concentrations and on insulin secretion and action in subjects with high fasting triglyceride concentrations.

Science.gov (United States)

Lopez, Sergio; Bermudez, Beatriz; Ortega, Almudena; Varela, Lourdes M; Pacheco, Yolanda M; Villar, Jose; Abia, Rocio; Muriana, Francisco J G

2011-03-01

The nature of dietary fats and fasting concentrations of triglycerides affect postprandial hypertriglyceridemia and glucose homeostasis. The objectives were to examine the effects of meals enriched in monounsaturated fatty acids (MUFAs) or saturated fatty acids (SFAs) on postprandial lipid, glucose, and insulin concentrations and to examine the extent of β cell function and insulin sensitivity in subjects with high fasting triglyceride concentrations. Fourteen men with fasting hypertriglyceridemia and normal glucose tolerance were given meals (≈10 kcal/kg body weight) containing MUFAs, SFAs, or no fat. Blood samples were collected at baseline and hourly over 8 h for analysis. The high-fat meals significantly increased postprandial concentrations of triglycerides, nonesterified fatty acids, and insulin and postprandial indexes of β cell function. However, postprandial indexes of insulin sensitivity decreased significantly. These effects were significantly attenuated with MUFAs relative to SFAs. MUFAs postprandially buffered β cell hyperactivity and insulin intolerance relative to SFAs in subjects with high fasting triglyceride concentrations. These data suggest that, in contrast with SFAs, MUFA-based strategies may provide cardiovascular benefits to persons at risk by limiting lipid and insulin excursions and may contribute to optimal glycemic control after meal challenges.

High-efficiency concentrator silicon solar cells

Energy Technology Data Exchange (ETDEWEB)

Sinton, R.A.; Cuevas, A.; King, R.R.; Swanson, R.M. (Stanford Univ., CA (USA). Solid-State Electronics Lab.)

1990-11-01

This report presents results from extensive process development in high-efficiency Si solar cells. An advanced design for a 1.56-cm{sup 2} cell with front grids achieved 26% efficiency at 90 suns. This is especially significant since this cell does not require a prismatic cover glass. New designs for simplified backside-contact solar cells were advanced from a status of near-nonfunctionality to demonstrated 21--22% for one-sun cells in sizes up to 37.5 cm{sup 2}. An efficiency of 26% was achieved for similar 0.64-cm{sup 2} concentrator cells at 150 suns. More fundamental work on dopant-diffused regions is also presented here. The recombination vs. various process and physical parameters was studied in detail for boron and phosphorous diffusions. Emitter-design studies based solidly upon these new data indicate the performance vs design parameters for a variety of the cases of most interest to solar cell designers. Extractions of p-type bandgap narrowing and the surface recombination for p- and n-type regions from these studies have a generality that extends beyond solar cells into basic device modeling. 68 refs., 50 figs.

Quantitative analysis of the improvement in high zoom maritime tracking due to real-time image enhancement

CSIR Research Space (South Africa)

Bachoo, AK

2011-04-01

Full Text Available This work aims to evaluate the improvement in the performance of tracking small maritime targets due to real-time enhancement of the video streams from high zoom cameras on pan-tilt pedestal. Due to atmospheric conditions these images can frequently...

Effect of oxygen vacancy and dopant concentration on the magnetic properties of high spin Co2+ doped TiO2 nanoparticles

International Nuclear Information System (INIS)

Choudhury, B.; Choudhury, A.; Maidul Islam, A.K.M.; Alagarsamy, P.; Mukherjee, M.

2011-01-01

Co doped TiO 2 nanoparticles have been synthesized by a simple sol-gel route taking 7.5, 9.5 and 10.5 mol% of cobalt concentration. Formation of nanoparticles is confirmed by XRD and TEM. Increase in d-spacing occurs for (0 0 4) and (2 0 0) peak with increase in impurity content. Valence states of Co and its presence in the doped material is confirmed by XPS and EDX. The entire vacuum annealed samples show weak ferromagnetism. Increased magnetization is found for 9.5 mol% but this value again decreases for 10.5 mol% due to antiferromagnetic interactions. A blocking temperature of 37.9 K is obtained, which shows shifting to high temperature as the dopant concentration is increased. The air annealed sample shows only paramagnetic behavior. Temperature dependent magnetic measurements for the air annealed sample shows antiferromagnetic behavior with a Curie-Weiss temperature of -16 K. Here we report that oxygen vacancy and cobalt aggregates are a key factor for inducing ferromagnetism-superparamagnetism in the vacuum annealed sample. Appearance of negative Curie-Weiss temperature reveals the presence of antiferromagnetic Co 3 O 4 , which is the oxidation result of metallic Co or cobalt clusters present on the host TiO 2 . - Research highlights: → Oxygen vacancy induces ferromagnetism in cobalt doped anatase TiO2 nanoparticles. → On air annealing the sample loses ferromagnetism giving rise to paramagnetism. → Saturation magnetization decreases at higher doping concentration. → Blocking of magnetic moment occurs due to the presence of cobalt clusters.

Barrier, mechanical and optical properties of whey protein concentrate films

Directory of Open Access Journals (Sweden)

Viviane Machado Azevedo

2014-08-01

Full Text Available Whey is recognized as a valuable source of high quality protein and, when processed as protein concentrate, may be used in the production of biodegradable films. The objective of the study was to develop films of whey protein concentrate 80% (WPC at concentrations of 6, 8, 10 and 12% and evaluate the influence of this factor in the barrier, mechanical and optical properties of the films. Treatments showed moisture content with a mean value of 22.10% ± 0.76and high solubility values between 56.67 to 62.42%. Thus, there is little or no influence of varying the concentration of WPC in these properties and high hydrophilicity of the films. With increasing concentration of WPC, increases the water vapor permeability of the films (7.42 x 10-13 to 3.49 x 10-12 g.m-1.s-1.Pa-1. The treatment at the concentration of 6% of WPC showed a higher modulus of elasticity (287.90 ± 41.79 MPa. Thegreater rigidity in films with higher concentrations is possibly due to the greater number of bonds between molecules of the polymeric matrix. The films have the same puncture resistance. The increased concentration of WPC promotes resistance to the action of a localized force. In general, films of whey protein concentrate in the tested concentrations exhibited slightly yellowish color and transparency, and can be used in food packaging that requiring intermediate permeability to water vapor, to keep moisture and texture desired.

G eobacter sp. SD-1 with enhanced electrochemical activity in high-salt concentration solutions

KAUST Repository

Sun, Dan; Call, Douglas; Wang, Aijie; Cheng, Shaoan; Logan, Bruce E.

2014-01-01

© 2014 Society for Applied Microbiology and John Wiley & Sons Ltd. Summary: An isolate, designated strain SD-1, was obtained from a biofilm dominated by Geobacter sulfurreducens in a microbial fuel cell. The electrochemical activity of strain SD-1 was compared with type strains, G.sulfurreducensPCA and Geobacter metallireducensGS-15, and a mixed culture in microbial electrolysis cells. SD-1 produced a maximum current density of 290±29Am-3 in a high-concentration phosphate buffer solution (PBS-H, 200mM). This current density was significantly higher than that produced by the mixed culture (189±44Am-3) or the type strains (<70Am-3). In a highly saline water (SW; 50mM PBS and 650mM NaCl), current by SD-1 (158±4Am-3) was reduced by 28% compared with 50mM PBS (220±4Am-3), but it was still higher than that of the mixed culture (147±19Am-3), and strains PCA and GS-15 did not produce any current. Electrochemical tests showed that the improved performance of SD-1 was due to its lower charge transfer resistance and more negative potentials produced at higher current densities. These results show that the electrochemical activity of SD-1 was significantly different than other Geobacter strains and mixed cultures in terms of its salt tolerance.

G eobacter sp. SD-1 with enhanced electrochemical activity in high-salt concentration solutions

KAUST Repository

Sun, Dan

2014-07-16

© 2014 Society for Applied Microbiology and John Wiley & Sons Ltd. Summary: An isolate, designated strain SD-1, was obtained from a biofilm dominated by Geobacter sulfurreducens in a microbial fuel cell. The electrochemical activity of strain SD-1 was compared with type strains, G.sulfurreducensPCA and Geobacter metallireducensGS-15, and a mixed culture in microbial electrolysis cells. SD-1 produced a maximum current density of 290±29Am-3 in a high-concentration phosphate buffer solution (PBS-H, 200mM). This current density was significantly higher than that produced by the mixed culture (189±44Am-3) or the type strains (<70Am-3). In a highly saline water (SW; 50mM PBS and 650mM NaCl), current by SD-1 (158±4Am-3) was reduced by 28% compared with 50mM PBS (220±4Am-3), but it was still higher than that of the mixed culture (147±19Am-3), and strains PCA and GS-15 did not produce any current. Electrochemical tests showed that the improved performance of SD-1 was due to its lower charge transfer resistance and more negative potentials produced at higher current densities. These results show that the electrochemical activity of SD-1 was significantly different than other Geobacter strains and mixed cultures in terms of its salt tolerance.

Immunoglobulin Concentration in Tears of Contact Lens Wearers

Directory of Open Access Journals (Sweden)

Rajendra P Maurya

2014-01-01

Conclusion: The relation of immunoglobulin concentration with increasing duration of wear and material of contact lens shows that tear immunoglobulin rise accrues due to mechanical stimulation, hence contact lenses should not be used for a long period and lenses of hard nature should be discouraged. The maintenance, cleaning and deproteinization of the lenses are of high importance to avoid immunostimulation.

Effect of concentrate feeder design on performance, eating and animal behavior, welfare, ruminal health, and carcass quality in Holstein bulls fed high-concentrate diets.

Science.gov (United States)

Verdú, M; Bach, A; Devant, M

2015-06-01

A total of 240 Holstein bulls (121 ± 2.0 kg initial BW; 99 ± 1.0 d of age), from 2 consecutive fattening cycles, were randomly allocated in 1 of 6 pens and assigned to 1 of the 3 treatments consisting of different concentrate feeder designs: a control feeder with 4 feeding spaces (CF), a feeder with less concentrate capacity (CFL), and a single-space feeder with lateral protections (SF). Each pen had a straw feeder and a drinker. All animals were fed a high-concentrate diet for ad libitum intake. Concentrate consumption was recorded daily using a computerized feeder, straw consumption was recorded weekly, and BW was recorded every 14 d. Animal behavior was registered on d 1, 3, 5, 8, and 14 and every 28 d by scan sampling. Eating behavior at concentrate feeders was filmed on d 12, 125, and 206. On d 7, 120, and 204, samples of rumen contents were collected for measurement of pH and VFA and blood samples were obtained to analyze NEFA, haptoglobin, glucose, and insulin. Animals were slaughtered after 223 d, and HCW and lesions of the rumen wall and liver were recorded. The accumulative concentrate consumption per animal tended (P = 0.09) to be greater with CF than with CFL and SF. Also, CV of concentrate consumption was greater (P carcass data. Also, no differences among treatments in rumen wall evaluation and liver abscesses were observed. At 7 and 204 d of study, SF bulls had greater (P animal welfare in Holstein bulls fed high-concentrate diets. However, at the beginning, there was evidence that animals fed using SF had problems with adaptation.

Human parvovirus B19 infection in hemophiliacs first infused with two high-purity, virally attenuated factor VIII concentrates.

Science.gov (United States)

Azzi, A; Ciappi, S; Zakvrzewska, K; Morfini, M; Mariani, G; Mannucci, P M

1992-03-01

Human parvovirus B19 can be transmitted by coagulation factor concentrates and is highly resistant to virucidal methods. To evaluate whether the additional removal of virus by chromatographic methods during the manufacture of high-purity concentrates reduces the risk of B19 transmission, we have prospectively evaluated the rate of anti-B19 seroconversion in two groups of susceptible (anti-B19 negative) hemophiliacs infused with high-purity, heated (pasteurized) or solvent-detergent-treated factor VIII concentrates. Both products infected a relatively high proportion of patients (nine of 20).

Traceable measurements of the activity concentration in air

CERN Document Server

Paul, A; Forkel-Wirth, Doris; Müller, A; Marcos, A

2002-01-01

The nuclear reactions induced by high energetic protons in heavy targets such as UC/sub 2/ and ThC cause a particular, complex radiation protection task at facilities like ISOLDE: the measurement of a mixture of different isotopes of the radioactive noble gas radon and the radon progenies in air. The knowledge of their respective activity concentration is fundamental for exposure assessments. Due to the complex mixture of activity concentrations in air, its precise determination is quite difficult. Therefore, a new procedure for taking reference samples was developed and implemented for the traceable measurement of the activity concentration of radioactive ions (e.g., radon progenies) in air. This technique is combined by measuring alpha -particles with a multi-wire ionization chamber for the parallel on-line determination of the activity concentration of different radon isotopes. (10 refs).

Enhanced cycling performance of a Li metal anode in a dimethylsulfoxide-based electrolyte using highly concentrated lithium salt for a lithium-oxygen battery

Science.gov (United States)

Togasaki, Norihiro; Momma, Toshiyuki; Osaka, Tetsuya

2016-03-01

Stable charge-discharge cycling behavior for a lithium metal anode in a dimethylsulfoxide (DMSO)-based electrolyte is strongly desired of lithium-oxygen batteries, because the Li anode is rapidly exhausted as a result of side reactions during cycling in the DMSO solution. Herein, we report a novel electrolyte design for enhancing the cycling performance of Li anodes by using a highly concentrated DMSO-based electrolyte with a specific Li salt. Lithium nitrate (LiNO3), which forms an inorganic compound (Li2O) instead of a soluble product (Li2S) on a lithium surface, exhibits a >20% higher coulombic efficiency than lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, and lithium perchlorate, regardless of the loading current density. Moreover, the stable cycling of Li anodes in DMSO-based electrolytes depends critically on the salt concentration. The highly concentrated electrolyte 4.0 M LiNO3/DMSO displays enhanced and stable cycling performance comparable to that of carbonate-based electrolytes, which had not previously been achieved. We suppose this enhancement is due to the absence of free DMSO solvent in the electrolyte and the promotion of the desolvation of Li ions on the solid electrolyte interphase surface, both being consequences of the unique structure of the electrolyte.

PKU: high plasma phenylalanine concentrations are associated with increased prevalence of mood swings.

Science.gov (United States)

Anjema, Karen; van Rijn, Margreet; Verkerk, Paul H; Burgerhof, Johannes G M; Heiner-Fokkema, M Rebecca; van Spronsen, Francjan J

2011-11-01

In phenylketonuria, knowledge about the relation between behavior and plasma phenylalanine is scarce. The aim of this study was to determine whether high phenylalanine is associated with disturbed behavior noticed by the patient and or close environment (parents or partners). 48 early treated PKU patients (median age 8.5, range 0-35 years) participated (median phenylalanine concentration in total sample 277 (range 89-1171) μmol/l; and in patients introvert or extravert behavior. The interviewer as well as the respondents were blinded with regard to the phenylalanine concentration. Patients reported less deviant behavior compared to close environment. Mood swings were positively associated with phenylalanine concentrations in the total group (P=0.039) and patients introvert and extravert behavior were not statistically significant. there is a positive association between phenylalanine concentrations and mood swings. Copyright © 2011 Elsevier Inc. All rights reserved.

Investigation on the effect of thermal resistances on a highly concentrated photovoltaic-thermoelectric hybrid system

International Nuclear Information System (INIS)

Zhang, Jin; Xuan, Yimin

2016-01-01

Highlights: • The highly concentrated PV-TE hybrid system is studied. • The performances of different cooling systems are analyzed and compared. • Sandwiching a copper plate between the PV and TE can improve the efficiency. • Four thermal design principles of the system are proposed. - Abstract: A thermal analysis of a highly concentrated photovoltaic-thermoelectric (PV-TE) hybrid system is carried out in this paper. Both the output power and the temperature distribution in the hybrid system are calculated by means of a three-dimensional numerical model. Three possible approaches for designing the highly concentrated PV-TE hybrid system are presented by analyzing the thermal resistance of the whole system. First, the sensitivity analysis shows that the thermal resistance between the TE module and the environment has a more great effect on the output power than the thermal resistance between the PV and the TE. The influence of the natural convection and the radiation can be ignored for the highly concentrated PV-TE hybrid system. Second, it is necessary to sandwich a copper plate between the PV and the TE for decreasing the thermal resistance between the PV and the TE. The role of the copper plate is to improve the temperature uniformity. Third, decreasing the area of PV cells can improve the efficiency of the highly concentrated PV-TE hybrid system. It should be pointed out that decreasing the area of PV cells also increases the total thermal resistance, but the raise of the efficiency is caused by the reduction of the heat transfer rate of the system. Therefore, the principle of minimizing the total thermal resistance may not be suitable for optimizing the area of PV cells.

Vasopressin activates Akt/mTOR pathway in smooth muscle cells cultured in high glucose concentration

Energy Technology Data Exchange (ETDEWEB)

Montes, Daniela K.; Brenet, Marianne; Muñoz, Vanessa C.; Burgos, Patricia V.; Villanueva, Carolina I. [Department of Physiology, Universidad Austral de Chile, Valdivia 509-9200 (Chile); Figueroa, Carlos D. [Department of Anatomy, Histology and Pathology, Universidad Austral de Chile, Valdivia 509-9200 (Chile); González, Carlos B., E-mail: cbgonzal@uach.cl [Department of Physiology, Universidad Austral de Chile, Valdivia 509-9200 (Chile); Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555 (United States)

2013-11-29

Highlights: •AVP induces mTOR phosphorylation in A-10 cells cultured in high glucose concentration. •The mTOR phosphorylation is mediated by the PI3K/Akt pathway activation. •The AVP-induced mTOR phosphorylation inhibited autophagy and stimulated cell proliferation. -- Abstract: Mammalian target of rapamycin (mTOR) complex is a key regulator of autophagy, cell growth and proliferation. Here, we studied the effects of arginine vasopressin (AVP) on mTOR activation in vascular smooth muscle cells cultured in high glucose concentration. AVP induced the mTOR phosphorylation in A-10 cells grown in high glucose, in contrast to cells cultured in normal glucose; wherein, only basal phosphorylation was observed. The AVP-induced mTOR phosphorylation was inhibited by a PI3K inhibitor. Moreover, the AVP-induced mTOR activation inhibited autophagy and increased thymidine incorporation in cells grown in high glucose. This increase was abolished by rapamycin which inhibits the mTORC1 complex formation. Our results suggest that AVP stimulates mTOR phosphorylation by activating the PI3K/Akt signaling pathway and, subsequently, inhibits autophagy and raises cell proliferation in A-10 cells maintained in high glucose concentration.

High nitrate concentrations in some Midwest United States streams in 2013 after the 2012 drought

Science.gov (United States)

Van Metre, Peter C.; Frey, Jeffrey W.; Musgrove, MaryLynn; Nakagaki, Naomi; Qi, Sharon L.; Mahler, Barbara J.; Wieczorek, Michael; Button, Daniel T.

2016-01-01

Nitrogen sources in the Mississippi River basin have been linked to degradation of stream ecology and to Gulf of Mexico hypoxia. In 2013, the USGS and the USEPA characterized water quality stressors and ecological conditions in 100 wadeable streams across the midwestern United States. Wet conditions in 2013 followed a severe drought in 2012, a weather pattern associated with elevated nitrogen concentrations and loads in streams. Nitrate concentrations during the May to August 2013 sampling period ranged from nitrate concentrations at the 100 sites were compared with May to June concentrations predicted from a regression model developed using historical nitrate data. Observed concentrations for 17 sites, centered on Iowa and southern Minnesota, were outside the 95% confidence interval of the regression-predicted mean, indicating that they were anomalously high. The sites with a nitrate anomaly had significantly higher May to June nitrate concentrations than sites without an anomaly (means, 19.8 and 3.6 mg L−1, respectively) and had higher antecedent precipitation indices, a measure of the departure from normal precipitation, in 2012 and 2013. Correlations between nitrate concentrations and watershed characteristics and nitrogen and oxygen isotopes of nitrate indicated that fertilizer and manure used in crop production, principally corn, were the dominant sources of nitrate. The anomalously high nitrate levels in parts of the Midwest in 2013 coincide with reported higher-than-normal nitrate loads in the Mississippi River.

Mechanisms of astrocytic K(+) clearance and swelling under high extracellular K(+) concentrations.

Science.gov (United States)

Murakami, Shingo; Kurachi, Yoshihisa

2016-03-01

In response to the elevation of extracellular K(+) concentration ([K(+)]out), astrocytes clear excessive K(+) to maintain conditions necessary for neural activity. K(+) clearance in astrocytes occurs via two processes: K(+) uptake and K(+) spatial buffering. High [K(+)]out also induces swelling in astrocytes, leading to edema and cell death in the brain. Despite the importance of astrocytic K(+) clearance and swelling, the underlying mechanisms remain unclear. Here, we report results from a simulation analysis of astrocytic K(+) clearance and swelling. Astrocyte models were constructed by incorporating various mechanisms such as intra/extracellular ion concentrations of Na(+), K(+), and Cl(-), cell volume, and models of Na,K-ATPase, Na-K-Cl cotransporter (NKCC), K-Cl cotransporter, inwardly-rectifying K(+) (KIR) channel, passive Cl(-) current, and aquaporin channel. The simulated response of astrocyte models under the uniform distribution of high [K(+)]out revealed significant contributions of NKCC and Na,K-ATPase to increases of intracellular K(+) and Cl(-) concentrations, and swelling. Moreover, we found that, under the non-uniform distribution of high [K(+)]out, KIR channels localized at synaptic clefts absorbed excess K(+) by depolarizing the equivalent potential of K(+) (E K) above membrane potential, while K(+) released through perivascular KIR channels was enhanced by hyperpolarizing E K and depolarizing membrane potential. Further analysis of simulated drug effects revealed that astrocyte swelling was modulated by blocking each of the ion channels and transporters. Our simulation analysis revealed controversial mechanisms of astrocytic K(+) clearance and swelling resulting from complex interactions among ion channels and transporters.

Investigation on the improved radiation hardness of silicon detectors with high oxygen concentration

International Nuclear Information System (INIS)

Moll, M.; Fretwurst, E.; Lindstroem, G.

2000-01-01

We present an investigation on the influence of the oxygen concentration on radiation-induced changes in the effective doping concentration of silicon detectors. Diodes fabricated from silicon with interstitial oxygen content ranging from below 2x10 14 to 9x10 17 cm -3 have been irradiated with fast neutrons up to a fluence of 2x10 15 cm -2 . Our main interest focused on the so-called stable damage component in the change of the effective doping concentration being of prime importance for the application of silicon detectors in high-energy physics experiments. We demonstrate, that with a high oxygen enrichment the donor removal is appreciably reduced, reaching a value of only 10% of the initial doping concentration for [O i ]=9x10 17 cm -3 , while for normal detector grade material with [O i ] below 5x10 16 cm -3 that value is 60-90%. Furthermore, we show that the fluence proportional introduction of stable acceptors is independent of the oxygen concentration with an averaged introduction rate of (1.49±0.03)x10 -2 cm -1 . Only one material was found exhibiting a significantly smaller value of about 0.6x10 -2 cm -1 and thus indicating the possibility to suppress the radiation-induced acceptor creation by material modification. Finally, we show that the experimental findings disagree in several important aspects with predictions made by microscopic defect kinetics models, leaving the physical background of some of the measured data as an open question

Intracerebral haemorrhage associated with hourly concentration of ambient particulate matter: case-crossover analysis.

Science.gov (United States)

Yamazaki, S; Nitta, H; Ono, M; Green, J; Fukuhara, S

2007-01-01

To examine the association of hourly time lagged concentration of ambient particulate matter and death due to stroke. Mortality data for five years (January 1990 to December 1994) were obtained from the Ministry of Health, Labour, and Welfare of Japan. Data were used only if the deceased was 65 years old or older at the time of death, if death was attributed to intracerebral haemorrhage or ischaemic stroke, and if the deceased lived in one of 13 major urban areas. Hourly mean concentrations of PM7, NO2, and photochemical oxidants were measured at monitoring stations in the 13 areas. Time stratified case-crossover analysis was used to examine the data for evidence of triggering stroke mortality. The 1-hour mean concentration of PM7 measured about 2 hours before death was associated with the risk of death due to intracerebral haemorrhage from April to September (odds ratio = 2.40, 95% CI 1.48 to 3.89, for exposure to PM7 of more than 200 microg/m3 (threshold)). The higher risk was independent of the 24-hour mean concentration of PM7. PM7 was not associated with death due to ischaemic stroke. Transiently high concentrations of PM7 are associated with death due to intracerebral haemorrhage. Air quality standards or guidelines for particulate matter should be based not only on 24-hour mean concentrations, but also on hourly data.

Intracerebral haemorrhage associated with hourly concentration of ambient particulate matter: case‐crossover analysis

Science.gov (United States)

Yamazaki, S; Nitta, H; Ono, M; Green, J; Fukuhara, S

2007-01-01

Aims To examine the association of hourly time lagged concentration of ambient particulate matter and death due to stroke. Methods Mortality data for five years (January 1990 to December 1994) were obtained from the Ministry of Health, Labour, and Welfare of Japan. Data were used only if the deceased was 65 years old or older at the time of death, if death was attributed to intracerebral haemorrhage or ischaemic stroke, and if the deceased lived in one of 13 major urban areas. Hourly mean concentrations of PM7, NO2, and photochemical oxidants were measured at monitoring stations in the 13 areas. Time stratified case‐crossover analysis was used to examine the data for evidence of triggering stroke mortality. Results The 1‐hour mean concentration of PM7 measured about 2 hours before death was associated with the risk of death due to intracerebral haemorrhage from April to September (odds ratio = 2.40, 95% CI 1.48 to 3.89, for exposure to PM7 of more than 200 μg/m3 (threshold)). The higher risk was independent of the 24‐hour mean concentration of PM7. PM7 was not associated with death due to ischaemic stroke. Conclusions Transiently high concentrations of PM7 are associated with death due to intracerebral haemorrhage. Air quality standards or guidelines for particulate matter should be based not only on 24‐hour mean concentrations, but also on hourly data. PMID:16847037

A flexible cell concentrator using inertial focusing.

Science.gov (United States)

Tu, Chunglong; Zhou, Jian; Liang, Yitao; Huang, Bobo; Fang, Yifeng; Liang, Xiao; Ye, Xuesong

2017-09-11

Cell concentration adjustment is intensively implemented routinely both in research and clinical laboratories. Centrifuge is the most prevalent technique for tuning biosample concentration. But it suffers from a number of drawbacks, such as requirement of experienced operator, high cost, low resolution, variable reproducibility and induced damage to sample. Herein we report on a cost-efficient alternative using inertial microfluidics. While the majority of existing literatures concentrate on inertial focusing itself, we identify the substantial role of the outlet system played in the device performance that has long been underestimated. The resistances of the outlets virtually involve in defining the cutoff size of a given inertial filtration channel. Following the comprehensive exploration of the influence of outlet system, we designed an inertial device with selectable outlets. Using both commercial microparticles and cultured Hep G2 cells, we have successfully demonstrated the automated concentration modification and observed several key advantages of our device as compared with conventional centrifuge, such as significantly reduced cell loss (only 4.2% vs. ~40% of centrifuge), better preservation of cell viability and less processing time as well as the increased reproducibility due to absence of manual operation. Furthermore, our device shows high effectiveness for concentrated sample (e.g., 1.8 × 10 6 cells/ml) as well. We envision its promising applications in the circumstance where repetitive sample preparation is intensely employed.

Hydrogen concentration and distribution in high-purity germanium crystals

International Nuclear Information System (INIS)

Hansen, W.L.; Haller, E.E.; Luke, P.N.

1981-10-01

High-purity germanium crystals used for making nuclear radiation detectors are usually grown in a hydrogen ambient from a melt contained in a high-purity silica crucible. The benefits and problems encountered in using a hydrogen ambient are reviewed. A hydrogen concentration of about 2 x 10 15 cm -3 has been determined by growing crystals in hydrogen spiked with tritium and counting the tritium β-decays in detectors made from these crystals. Annealing studies show that the hydrogen is strongly bound, either to defects or as H 2 with a dissociation energy > 3 eV. This is lowered to 1.8 eV when copper is present. Etching defects in dislocation-free crystals grown in hydrogen have been found by etch stripping to have a density of about 1 x 10 7 cm -3 and are estimated to contain 10 8 H atoms each

High-order optical nonlinearities in nanocomposite films dispersed with semiconductor quantum dots at high concentrations

International Nuclear Information System (INIS)

Tomita, Yasuo; Matsushima, Shun-suke; Yamagami, Ryu-ichi; Jinzenji, Taka-aki; Sakuma, Shohei; Liu, Xiangming; Izuishi, Takuya; Shen, Qing

2017-01-01

We describe the nonlinear optical properties of inorganic-organic nanocomposite films in which semiconductor CdSe quantum dots as high as 6.8 vol.% are dispersed. Open/closed Z-scan measurements, degenerate multi-wave mixing and femtosecond pump-probe/transient grating measurements are conducted. It is shown that the observed fifth-order optical nonlinearity has the cascaded third-order contribution that becomes prominent at high concentrations of CdSe QDs. It is also shown that there are picosecond-scale intensity-dependent and nanosecond-scale intensity-independent decay components in absorptive and refractive nonlinearities. The former is caused by the Auger process, while the latter comes from the electron-hole recombination process. (paper)

Biodegradation of high concentrations of phenol by baker’s yeast in anaerobic sequencing batch reactor

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Ali Asghar Najafpoor

2015-06-01

Full Text Available Background: Phenol, as a pure substance, is used in many fields because of its disinfectant, germicidal, local anesthetic, and peptizing properties. Aqueous solutions of phenol are produced as waste in industries and discharged into the environment. Therefore, elevated concentrations of phenol may be found in air or water because of industrial discharge or the use of phenolic products. Method: The strains of Saccharomyces cerevisiae used in this project were natural strains previously purchased from Razavy company. They were grown at 30°C on Petri plates containing yeast extract glucose (YGC and then purified by being spread onto new plates, and isolated colonies were obtained. These colonies provided the basis of selection. Prepared strains were applied in anaerobic sequencing batch reactors (ASBRs as first seed. The experiment conditions were optimized using response surface methodology (RSM. After the determined runs were performed using Design-Expert software, data were analyzed using mentioned software as well. Results: This study evaluated the capability of baker’s yeast to remove phenol in high concentrations. The tested strains showed excellent tolerance to phenol toxicity at concentrations up to 6100 mg/L. Study of the batch degradation process showed that the phenol removal rate could exceed 99.9% in 24 hours at a concentration of 1000 mg/L. The results showed catechol is the first intermediate product of phenol degradation. In survey results of the Design–Expert software, R2 and Adeq precision were 0.97 and 25.65, respectively. Conclusion: The results demonstrated that ASBR performs robustly under variable influent concentrations of inhibitory compounds. The high removal performance despite the high phenol concentration may be a result of reactor operating strategies. Based on the progressive increase of inlet phenol concentration, allowing for an enhanced biomass acclimation in a short time, results at the microbiological levels

High concentrations of heavy metals in PM from ceramic factories of Southern Spain

Science.gov (United States)

Sánchez de la Campa, Ana M.; de la Rosa, Jesús D.; González-Castanedo, Yolanda; Fernández-Camacho, Rocío; Alastuey, Andrés; Querol, Xavier; Pio, Casimiro

2010-06-01

In this study, physicochemical characterization of Atmospheric Particulate Matter (PM) was performed in an urban-industrial site background (Bailén, Southern Spain), highly influenced by the impact of emission plumes from ceramic factories. This area is considered one of the towns with the highest PM 10 levels and average SO 2 concentration in Spain. A three stages methodology was used: 1) real-time measurements of levels of PM 10 and gaseous pollutants, and sampling of PM; 2) chemical characterization using ICP-MS, ICP-OES, CI and TOT, and source apportionment analysis (receptor modelling) of PM; and 3) chemical characterization of emission plumes derived from representative factories. High ambient air concentrations were found for most major components and trace elements compared with other industrialized towns in Spain. V and Ni are considered fingerprints of PM derived from the emissions of brick factories in this area, and were shown to be of particular interest. This highlights the high V and Ni concentrations in PM 10 (122 ngV/m 3 and 23.4 ngNi/m 3), with Ni exceeding the 2013 annual target value for the European Directive 2004/107/EC (20 ng/m 3). The methodology of this work can be used by Government departments responsible for Environment and Epidemiology in planning control strategies for improving air quality.

Fine particle number and mass concentration measurements in urban Indian households.

Science.gov (United States)

Mönkkönen, P; Pai, P; Maynard, A; Lehtinen, K E J; Hämeri, K; Rechkemmer, P; Ramachandran, G; Prasad, B; Kulmala, M

2005-07-15

Fine particle number concentration (D(p)>10 nm, cm(-3)), mass concentrations (approximation of PM(2.5), microg m(-3)) and indoor/outdoor number concentration ratio (I/O) measurements have been conducted for the first time in 11 urban households in India, 2002. The results indicate remarkable high indoor number and mass concentrations and I/O number concentration ratios caused by cooking. Besides cooking stoves that used liquefied petroleum gas (LPG) or kerosene as the main fuel, high indoor concentrations can be explained by poor ventilation systems. Particle number concentrations of more than 300,000 cm(-3) and mass concentrations of more than 1000 microg m(-3) were detected in some cases. When the number and mass concentrations during cooking times were statistically compared, a correlation coefficient r>0.50 was observed in 63% of the households. Some households used other fuels like wood and dung cakes along with the main fuel, but also other living activities influenced the concentrations. In some areas, outdoor combustion processes had a negative impact on indoor air quality. The maximum concentrations observed in most cases were due to indoor combustion sources. Reduction of exposure risk and health effects caused by poor indoor air in urban Indian households is possible by improving indoor ventilation and reducing penetration of outdoor particles.

Estimation of Radionuclide Concentrations and Average Annual Committed Effective Dose due to Ingestion for the Population in the Red River Delta, Vietnam.

Science.gov (United States)

Van, Tran Thi; Bat, Luu Tam; Nhan, Dang Duc; Quang, Nguyen Hao; Cam, Bui Duy; Hung, Luu Viet

2018-02-16

Radioactivity concentrations of nuclides of the 232 Th and 238 U radioactive chains and 40 K, 90 Sr, 137 Cs, and 239+240 Pu were surveyed for raw and cooked food of the population in the Red River delta region, Vietnam, using α-, γ-spectrometry, and liquid scintillation counting techniques. The concentration of 40 K in the cooked food was the highest compared to those of other radionuclides ranging from (23 ± 5) (rice) to (347 ± 50) Bq kg -1 dw (tofu). The 210 Po concentration in the cooked food ranged from its limit of detection (LOD) of 5 mBq kg -1  dw (rice) to (4.0 ± 1.6) Bq kg -1  dw (marine bivalves). The concentrations of other nuclides of the 232 Th and 238 U chains in the food were low, ranging from LOD of 0.02 Bq kg -1  dw to (1.1 ± 0.3) Bq kg -1  dw. The activity concentrations of 90 Sr, 137 Cs, and 239+240 Pu in the food were minor compared to that of the natural radionuclides. The average annual committed effective dose to adults in the study region was estimated and it ranged from 0.24 to 0.42 mSv a -1 with an average of 0.32 mSv a -1 , out of which rice, leafy vegetable, and tofu contributed up to 16.2%, 24.4%, and 21.3%, respectively. The committed effective doses to adults due to ingestion of regular diet in the Red River delta region, Vietnam are within the range determined in other countries worldwide. This finding suggests that Vietnamese food is safe for human consumption with respect to radiation exposure.

Root based responses account for Psidium guajava survival at high nickel concentration.

Science.gov (United States)

Bazihizina, Nadia; Redwan, Mirvat; Taiti, Cosimo; Giordano, Cristiana; Monetti, Emanuela; Masi, Elisa; Azzarello, Elisa; Mancuso, Stefano

2015-02-01

The presence of Psidium guajava in polluted environments has been reported in recent studies, suggesting that this species has a high tolerance to the metal stress. The present study aims at a physiological characterization of P. guajava response to high nickel (Ni) concentrations in the root-zone. Three hydroponic experiments were carried out to characterize the effects of toxic Ni concentrations on morphological and physiological parameters of P. guajava, focusing on Ni-induced damages at the root-level and root ion fluxes. With up to 300μM NiSO4 in the root-zone, plant growth was similar to that in control plants, whereas at concentrations higher than 1000μM NiSO4 there was a progressive decline in plant growth and leaf gas exchange parameters; this occurred despite, at all considered concentrations, plants limited Ni(2+) translocation to the shoot, therefore avoiding shoot Ni(2+) toxicity symptoms. Maintenance of plant growth with 300μM Ni(2+) was associated with the ability to retain K(+) in the roots meanwhile 1000 and 3000μM NiSO4 led to substantial K(+) losses. In this study, root responses mirror all plant performances suggesting a direct link between root functionality and Ni(2+) tolerance mechanisms and plant survival. Considering that Ni was mainly accumulated in the root system, the potential use of P. guajava for Ni(2+) phytoextraction in metal-polluted soils is limited; nevertheless, the observed physiological changes indicate a good Ni(2+) tolerance up to 300μM NiSO4 suggesting a potential role for the phytostabilization of polluted soils. Copyright © 2014 Elsevier GmbH. All rights reserved.

Observations of high droplet number concentrations in Southern Ocean boundary layer clouds

Directory of Open Access Journals (Sweden)

T. Chubb

2016-01-01

Full Text Available Cloud physics data collected during the NSF/NCAR High-performance Instrumented Airborne Platform for Environmental Research (HIAPER Pole-to-Pole Observations (HIPPO campaigns provide a snapshot of unusual wintertime microphysical conditions in the boundary layer over the Southern Ocean. On 29 June 2011, the HIAPER sampled the boundary layer in a region of pre-frontal warm air advection between 58 and 48° S to the south of Tasmania. Cloud droplet number concentrations were consistent with climatological values in the northernmost profiles but were exceptionally high for wintertime in the Southern Ocean at 100–200 cm−3 in the southernmost profiles. Sub-micron (0.06  < D <  1 µm aerosol concentrations for the southern profiles were up to 400 cm−3. Analysis of back trajectories and atmospheric chemistry observations revealed that while conditions in the troposphere were more typical of a clean remote ocean airmass, there was some evidence of continental or anthropogenic influence. However, the hypothesis of long-range transport of continental aerosol fails to explain the magnitude of the aerosol and cloud droplet concentration in the boundary layer. Instead, the gale force surface winds in this case (wind speed at 167 m above sea level was  > 25 m s−1 were most likely responsible for production of sea spray aerosol which influenced the microphysical properties of the boundary layer clouds. The smaller size and higher number concentration of cloud droplets is inferred to increase the albedo of these clouds, and these conditions occur regularly, and are expected to increase in frequency, over windy parts of the Southern Ocean.

Effects of turbulence on warm clouds and precipitation with various aerosol concentrations

Science.gov (United States)

Lee, Hyunho; Baik, Jong-Jin; Han, Ji-Young

2015-02-01

This study investigates the effects of turbulence-induced collision enhancement (TICE) on warm clouds and precipitation by changing the cloud condensation nuclei (CCN) number concentration using a two-dimensional dynamic model with bin microphysics. TICE is determined according to the Taylor microscale Reynolds number and the turbulent dissipation rate. The thermodynamic sounding used in this study is characterized by a warm and humid atmosphere with a capping inversion layer, which is suitable for simulating warm clouds. For all CCN concentrations, TICE slightly reduces the liquid water path during the early stage of cloud development and accelerates the onset of surface precipitation. However, changes in the rainwater path and in the amount of surface precipitation that are caused by TICE depend on the CCN concentrations. For high CCN concentrations, the mean cloud drop number concentration (CDNC) decreases and the mean effective radius increases due to TICE. These changes cause an increase in the amount of surface precipitation. However, for low CCN concentrations, changes in the mean CDNC and in the mean effective radius induced by TICE are small and the amount of surface precipitation decreases slightly due to TICE. A decrease in condensation due to the accelerated coalescence between droplets explains the surface precipitation decrease. In addition, an increase in the CCN concentration can lead to an increase in the amount of surface precipitation, and the relationship between the CCN concentration and the amount of surface precipitation is affected by TICE. It is shown that these results depend on the atmospheric relative humidity.

Performance analysis of high-concentrated multi-junction solar cells in hot climate

Science.gov (United States)

Ghoneim, Adel A.; Kandil, Kandil M.; Alzanki, Talal H.; Alenezi, Mohammad R.

2018-03-01

Multi-junction concentrator solar cells are a promising technology as they can fulfill the increasing energy demand with renewable sources. Focusing sunlight upon the aperture of multi-junction photovoltaic (PV) cells can generate much greater power densities than conventional PV cells. So, concentrated PV multi-junction solar cells offer a promising way towards achieving minimum cost per kilowatt-hour. However, these cells have many aspects that must be fixed to be feasible for large-scale energy generation. In this work, a model is developed to analyze the impact of various atmospheric factors on concentrator PV performance. A single-diode equivalent circuit model is developed to examine multi-junction cells performance in hot weather conditions, considering the impacts of both temperature and concentration ratio. The impacts of spectral variations of irradiance on annual performance of various high-concentrated photovoltaic (HCPV) panels are examined, adapting spectra simulations using the SMARTS model. Also, the diode shunt resistance neglected in the existing models is considered in the present model. The present results are efficiently validated against measurements from published data to within 2% accuracy. Present predictions show that the single-diode model considering the shunt resistance gives accurate and reliable results. Also, aerosol optical depth (AOD) and air mass are most important atmospheric parameters having a significant impact on HCPV cell performance. In addition, the electrical efficiency (η) is noticed to increase with concentration to a certain concentration degree after which it decreases. Finally, based on the model predictions, let us conclude that the present model could be adapted properly to examine HCPV cells' performance over a broad range of operating conditions.

Estimating NOx emissions and surface concentrations at high spatial resolution using OMI

Science.gov (United States)

Goldberg, D. L.; Lamsal, L. N.; Loughner, C.; Swartz, W. H.; Saide, P. E.; Carmichael, G. R.; Henze, D. K.; Lu, Z.; Streets, D. G.

2017-12-01

In many instances, NOx emissions are not measured at the source. In these cases, remote sensing techniques are extremely useful in quantifying NOx emissions. Using an exponential modified Gaussian (EMG) fitting of oversampled Ozone Monitoring Instrument (OMI) NO2 data, we estimate NOx emissions and lifetimes in regions where these emissions are uncertain. This work also presents a new high-resolution OMI NO2 dataset derived from the NASA retrieval that can be used to estimate surface level concentrations in the eastern United States and South Korea. To better estimate vertical profile shape factors, we use high-resolution model simulations (Community Multi-scale Air Quality (CMAQ) and WRF-Chem) constrained by in situ aircraft observations to re-calculate tropospheric air mass factors and tropospheric NO2 vertical columns during summertime. The correlation between our satellite product and ground NO2 monitors in urban areas has improved dramatically: r2 = 0.60 in new product, r2 = 0.39 in operational product, signifying that this new product is a better indicator of surface concentrations than the operational product. Our work emphasizes the need to use both high-resolution and high-fidelity models in order to re-calculate vertical column data in areas with large spatial heterogeneities in NOx emissions. The methodologies developed in this work can be applied to other world regions and other satellite data sets to produce high-quality region-specific emissions estimates.

Sedimentation Characteristics of Kaolin and Bentonite in Concentrated Solutions

Directory of Open Access Journals (Sweden)

Abdulah Obut

2005-11-01

Full Text Available The sedimentation characteristics of two clays, namely kaolinite and bentonite, were determinated at high clay (5 % wt/vol and electrolyte (1 N concentrations using various inorganic-organic compounds. It was observed that the settling behaviour of kaolinite (1:1 clay and montmorillonite (2:1 clay is quite different due to the structural differences between these minerals. Although, similar initial settling rates and final sediment volumes were obtained after 24 hours of settling time for kaolin suspensions, the corresponding rates and volumes for bentonite suspensions varied greatly with the used chemical compound. According to the experimental results, a further intensive theoretical and experimental investigation is needed to reveal the mechanism underlying the sedimentation characteristics of clay minerals at high clay and electrolyte concentrations.

Collecting performance of an evacuated tubular solar high-temperature air heater with concentric tube heat exchanger

International Nuclear Information System (INIS)

Wang, Ping-Yang; Li, Shuang-Fei; Liu, Zhen-Hua

2015-01-01

Highlights: • A novel evacuated tube solar high temperature air heater is designed. • The solar air heater system consists of 30 linked collecting units. • Every unit consisted of a evacuated tube, a simplified CPC and concentric tube. • The flow air is heated over temperature of 200 °C. - Abstract: A set of evacuated tube solar high temperature air heaters with simplified CPC (compound parabolic concentrator) and concentric tube heat exchanger is designed to provide flow air with a temperature of 150–230 °C for industrial production. The solar air heater system consists of 30 linked collecting units. Each unit includes a simplified CPC and an all-glass evacuated tube absorber with a concentric copper tube heat exchanger installed inside. A stainless steel mesh layer with high thermal conductivity is filled between the evacuated tube and the concentric copper tube. Air passes through each collecting unit, and its temperature increases progressively. An experimental investigation of the thermal performance of the air heater is performed, and the experimental results demonstrate the presented high-temperature solar air heater has excellent collecting performance and large output power, even in the winter. The measured thermal efficiency corresponding to the air temperature of 70 °C reaches 0.52. With the increase of air temperature, thermal efficiency reaches 0.35 at an air temperature of 150 °C, and 0.21 at an air temperature of 220 °C.

Quality evaluation of moluodan concentrated pill using high-performance liquid chromatography fingerprinting coupled with chemometrics.

Science.gov (United States)

Tao, Lingyan; Zhang, Qing; Wu, Yongjiang; Liu, Xuesong

2016-12-01

In this study, a fast and effective high-performance liquid chromatography method was developed to obtain a fingerprint chromatogram and quantitative analysis simultaneously of four indexes including gallic acid, chlorogenic acid, albiflorin and paeoniflorin of the traditional Chinese medicine Moluodan Concentrated Pill. The method was performed by using a Waters X-bridge C 18 reversed phase column on an Agilent 1200S high-performance liquid chromatography system coupled with diode array detection. The mobile phase of the high-performance liquid chromatography method was composed of 20 mmol/L phosphate solution and acetonitrile with a 1 mL/min eluent velocity, under a detection temperature of 30°C and a UV detection wavelength of 254 nm. After the methodology validation, 16 batches of Moluodan Concentrated Pill were analyzed by this high-performance liquid chromatography method and both qualitative and quantitative evaluation results were achieved by similarity analysis, principal component analysis and hierarchical cluster analysis. The results of these three chemometrics were in good agreement and all indicated that batch 10 and batch 16 showed significant differences with the other 14 batches. This suggested that the developed high-performance liquid chromatography method could be applied in the quality evaluation of Moluodan Concentrated Pill. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phenomenon of energy concentration in high-energy family events of cosmic rays

CERN Document Server

Wang He; Dai Zhi Qiang; Xue Liang; Feng Cun Feng; Zhang Xue Yao; Li Jin; Zhang Nai Jian; He Mao; Wang Cheng Rui; Ren Jing Ru; Lu Sui Ling

2002-01-01

The phenomenon of energy concentration in high-energy family events of cosmic rays is studied by comparing the results of family events of total visible energies 100-400 TeV observed in the Kanbala emulsion chamber experiment with the Monte Carlo simulation data. The simulation is made by the program CORSIKA in which QGSJET is applied as the hadronic interaction model, and the chemical composition of primary cosmic rays is obtained from the rigidity-cut model and the extrapolation of new results of direct measurements. This shows that the whole distribution tendency of the rate of energy concentration of simulated family events is basically consistent with that of the experiment

Feeding a high-concentrate corn straw diet induced epigenetic alterations in the mammary tissue of dairy cows.

Directory of Open Access Journals (Sweden)

Guozhong Dong

Full Text Available The objective of this study was to investigate the effects of feeding a high-concentrate corn straw (HCS diet (65% concentrate+35% corn straw on the epigenetic changes in the mammary tissue of dairy cows in comparison with a low-concentrate corn straw (LCS diet (46% concentrate+54% corn straw and with a low-concentrate mixed forage (LMF diet (46% concentrate+54% mixed forage.Multiparous mid-lactation Chinese Holstein cows were fed one of these three diets for 6 weeks, at which time blood samples and mammary tissue samples were collected. Mammary arterial and venous blood samples were analyzed for lipopolysaccharide (LPS concentrations while mammary tissue samples were assayed for histone H3 acetylation and the methylation of specific genes associated with fat and protein synthesis.Extraction of histones and quantification of histone H3 acetylation revealed that acetylation was significantly reduced in cows fed the HCS diet, as compared with cows fed the LCS diet. Cows fed the HCS diet had significantly higher LPS concentrations in the mammary arterial blood, as compared with cows fed the LCS diet. We found that the extent of histone H3 acetylation was negatively correlated with LPS concentrations. The methylation of the stearoyl-coenzyme A desaturase gene associated with milk fat synthesis was increased in cows fed the HCS diet. By contrast, methylation of the gene encoding the signal transducer and activator of transcription 5A was reduced in cows fed the HCS diet, suggesting that feeding a high-concentrate corn straw diet may alter the methylation of specific genes involved in fat and protein synthesis in the mammary tissue of dairy cows.Feeding the high-concentrate diet induced epigenetic changes in the mammary tissues of dairy cows, possibly through effecting the release of differing amounts of LPS into the mammary blood.

Using fractional extraction method to separate Mo from U in high concentration solution

International Nuclear Information System (INIS)

Zhao Pinzhi; Cheng Guangrong; Ma Xiuhua

1996-01-01

The author presents investigation on separating Mo from U in acid high concentration lixivium with fractional extraction of secondary amine (7203) and D2EHPA and preparing qualified products of ammonium molybdate and sodium diuranate

Optimization of a Point Focus Concentration Photovoltaic System with Passive Cooling

International Nuclear Information System (INIS)

Chenlo, F.

2015-01-01

The objective of this work is modeling the temperature of photovoltaic (PV) solar cells operating in concentration systems with circular geometry and coupled to a heat sink plate for passive cooling. The proposed thermal behavior model analyses the temperature surface distribution of both PV solar cell and heat sink plate as function of light concentration. The model also allows analyzing the influence of other parameters such as uniform and non-uniform variation of the heat sink plate thickness or variation of the thermal transmission coefficient. The optimal range of the concentration factor is studied using simple models for the PV solar cell efficiency and Fresnel lens concentrator performance together with a function of costs applied to medium concentration silicon crystalline PV cells and high efficiency and high concentration multi-junction PV cells. Finally, experimental main parameters and its procedures measurement for concentration systems are presented. Modeling results show that the use of a high conductivity disk thermally coupled between the rear side of the cell and the cooling plate reduces the working cell temperature. Results also indicates that use of a light redirecting prism by total internal reflection of sunlight, reduces optical losses due to concentrator defects and chromatic aberration and increases the angle tracking error acceptance without having to increase the area of the PV solar cell

Plasma methylphenidate concentrations in youths treated with high-dose osmotic release oral system formulation.

Science.gov (United States)

Stevens, Jonathan R; George, Robert A; Fusillo, Steven; Stern, Theodore A; Wilens, Timothy E

2010-02-01

Children and adolescents are being treated increasingly for attention-deficit/hyperactivity disorder (ADHD) with a variety of stimulants in higher than Food and Drug Administration (FDA)-approved doses and in combination with other medications. We sought to determine methylphenidate (MPH) concentrations in children and adolescents treated with high-dose, extended-release osmotic release oral system (OROS) MPH plus concomitant medications, and to examine MPH concentrations with respect to the safety and tolerability of treatment. Plasma MPH concentrations were measured by liquid chromatography-mass spectrometry 4-5 hours after administration of medication in a sample of youths diagnosed with ADHD. These youths were treated naturalistically with higher than FDA-approved doses of OROS MPH in addition to their concomitant medications. Markers of safety and tolerability (e.g., measures of blood pressure and heart rate) were also examined. Among the 17 patients (with a mean age of 16.2 +/- 2 years and a mean number of concurrent medications of 2.23 +/- 0.94), the mean plasma MPH concentration was 28 +/- 9.1 ng/mL, despite a mean daily dose of OROS MPH of 169 +/- 5 mg (3.0 +/- 0.8 mg/kg per day). No patient had a plasma MPH level >or=50 ng/mL or clinical signs of stimulant toxicity. No correlation was found between plasma MPH concentrations and OROS MPH dose or changes in vital signs. High-dose OROS MPH, used in combination with other medications, was not associated with either unusually elevated plasma MPH concentrations or with clinically meaningful changes in vital signs. Study limitations include a single time-point sampling of MPH concentrations, a small sample size, and a lack of outcome measures to address treatment effectiveness.

Technical note: False low turbidity readings from optical probes during high suspended-sediment concentrations

Science.gov (United States)

Voichick, Nicholas; Topping, David J.; Griffiths, Ronald E.

2018-03-01

Turbidity, a measure of water clarity, is monitored for a variety of purposes including (1) to help determine whether water is safe to drink, (2) to establish background conditions of lakes and rivers and detect pollution caused by construction projects and stormwater discharge, (3) to study sediment transport in rivers and erosion in catchments, (4) to manage siltation of water reservoirs, and (5) to establish connections with aquatic biological properties, such as primary production and predator-prey interactions. Turbidity is typically measured with an optical probe that detects light scattered from particles in the water. Probes have defined upper limits of the range of turbidity that they can measure. The general assumption is that when turbidity exceeds this upper limit, the values of turbidity will be constant, i.e., the probe is pegged; however, this assumption is not necessarily valid. In rivers with limited variation in the physical properties of the suspended sediment, at lower suspended-sediment concentrations, an increase in suspended-sediment concentration will cause a linear increase in turbidity. When the suspended-sediment concentration in these rivers is high, turbidity levels can exceed the upper measurement limit of an optical probe and record a constant pegged value. However, at extremely high suspended-sediment concentrations, optical turbidity probes do not necessarily stay pegged at a constant value. Data from the Colorado River in Grand Canyon, Arizona, USA, and a laboratory experiment both demonstrate that when turbidity exceeds instrument-pegged conditions, increasing suspended-sediment concentration (and thus increasing turbidity) may cause optical probes to record decreasing false turbidity values that appear to be within the valid measurement range of the probe. Therefore, under high-turbidity conditions, other surrogate measurements of turbidity (e.g., acoustic-attenuation measurements or suspended-sediment samples) are necessary to

Methods to assess high-resolution subsurface gas concentrations and gas fluxes in wetland ecosystems

DEFF Research Database (Denmark)

Elberling, Bo; Kühl, Michael; Glud, Ronnie Nøhr

2013-01-01

The need for measurements of soil gas concentrations and surface fluxes of greenhouse gases at high temporal and spatial resolution in wetland ecosystem has lead to the introduction of several new analytical techniques and methods. In addition to the automated flux chamber methodology for high-re...

Analysis of antibody aggregate content at extremely high concentrations using sedimentation velocity with a novel interference optics.

Science.gov (United States)

Schilling, Kristian; Krause, Frank

2015-01-01

Monoclonal antibodies represent the most important group of protein-based biopharmaceuticals. During formulation, manufacturing, or storage, antibodies may suffer post-translational modifications altering their physical and chemical properties. Such induced conformational changes may lead to the formation of aggregates, which can not only reduce their efficiency but also be immunogenic. Therefore, it is essential to monitor the amount of size variants to ensure consistency and quality of pharmaceutical antibodies. In many cases, antibodies are formulated at very high concentrations > 50 g/L, mostly along with high amounts of sugar-based excipients. As a consequence, all routine aggregation analysis methods, such as size-exclusion chromatography, cannot monitor the size distribution at those original conditions, but only after dilution and usually under completely different solvent conditions. In contrast, sedimentation velocity (SV) allows to analyze samples directly in the product formulation, both with limited sample-matrix interactions and minimal dilution. One prerequisite for the analysis of highly concentrated samples is the detection of steep concentration gradients with sufficient resolution: Commercially available ultracentrifuges are not able to resolve such steep interference profiles. With the development of our Advanced Interference Detection Array (AIDA), it has become possible to register interferograms of solutions as highly concentrated as 150 g/L. The other major difficulty encountered at high protein concentrations is the pronounced non-ideal sedimentation behavior resulting from repulsive intermolecular interactions, for which a comprehensive theoretical modelling has not yet been achieved. Here, we report the first SV analysis of highly concentrated antibodies up to 147 g/L employing the unique AIDA ultracentrifuge. By developing a consistent experimental design and data fit approach, we were able to provide a reliable estimation of the minimum

Circulating adiponectin concentration and body composition are altered in response to high-intensity interval training.

Science.gov (United States)

Shing, Cecilia M; Webb, Jessica J; Driller, Matthew W; Williams, Andrew D; Fell, James W

2013-08-01

Adiponectin influences metabolic adaptations that would prove beneficial to endurance athletes, and yet to date there is little known about the response of adiponectin concentrations to exercise, and, in particular, the response of this hormone to training in an athlete population. This study aimed to determine the response of plasma adiponectin concentrations to acute exercise after 2 different training programs and to determine the influence of the training on body composition. Seven state-level representative rowers (age: 19 ± 1.2 years [mean ± SD], height: 1.77 ± 0.10 m, body mass: 74.0 ± 10.7 kg, VO2peak 62.1 ± 7.0 ml·kg·min) participated in the double-blind, randomized crossover investigation. Rowers performed an incremental graded exercise test before and after completing 4 weeks of high-intensity interval ergometer training and 4 weeks of traditional ergometer rowing training. Rowers' body composition was assessed at baseline and after each training program. Significant increases in plasma adiponectin concentration occurred in response to maximal exercise after completion of the high-intensity interval training (p = 0.016) but not after traditional ergometer rowing training (p = 0.69). The high-intensity interval training also resulted in significant increases in mean 4-minute power output (p = 0.002) and VO2peak (p = 0.05), and a decrease in body fat percentage (p = 0.022). Mean 4-minute power output, VO2peak, and body fat percentage were not significantly different after 4 weeks of traditional ergometer rowing training (p > 0.05). Four weeks of high-intensity interval training is associated with an increase in adiponectin concentration in response to maximal exercise and a reduction in body fat percentage. The potential for changes in adiponectin concentration to reflect positive training adaptations and athlete performance level should be further explored.

Influence of a High-Pressure Comminution Technology on Concentrate Yields in Copper Ore Flotation Processes

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Saramak D.

2014-10-01

Full Text Available The article concerns the issues of flotation process effectiveness in relationship to the operating conditions of a high-pressure comminution process course. Experimental programme covering a flotation laboratory batch tests was a verification technique of a high-pressure crushing operations course. The most favorable values of flotation concentrate weight recoveries were obtained for the pressing force 6 kN and 4% of the feed moisture. It was also determined the model of the concentrate weight recovery as a function of pressing force in the press and feed moisture content. This model was the basis for the optimization of effects of copper ore flotation processes preceded in high-pressure crushing operation in roller presses.

Generic Modelling of Faecal Indicator Organism Concentrations in the UK

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Carl M. Stapleton

2011-06-01

Full Text Available To meet European Water Framework Directive requirements, data are needed on faecal indicator organism (FIO concentrations in rivers to enable the more heavily polluted to be targeted for remedial action. Due to the paucity of FIO data for the UK, especially under high-flow hydrograph event conditions, there is an urgent need by the policy community for generic models that can accurately predict FIO concentrations, thus informing integrated catchment management programmes. This paper reports the development of regression models to predict base- and high-flow faecal coliform (FC and enterococci (EN concentrations for 153 monitoring points across 14 UK catchments, using land cover, population (human and livestock density and other variables that may affect FIO source strength, transport and die-off. Statistically significant models were developed for both FC and EN, with greater explained variance achieved in the high-flow models. Both land cover and, in particular, population variables are significant predictors of FIO concentrations, with r2 maxima for EN of 0.571 and 0.624, respectively. It is argued that the resulting models can be applied, with confidence, to other UK catchments, both to predict FIO concentrations in unmonitored watercourses and evaluate the likely impact of different land use/stocking level and human population change scenarios.

Advanced Oxidation Processes (AOPs for Refinery Wastewater Treatment Contains High Phenol Concentration

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Azizah Alif Nurul

2018-01-01

Full Text Available Petroleum Refinery wastewater is characterized by a high phenol content. Phenol is toxic and resistant to biological processes for treatment of the petroleum refinery wastewater. The combination of an AOP and a biological process can be used for treatment of the refinery wastewater. It is necessary to conduct a study to determine the appropriate condition of AOP to meet the phenol removal level. Two AOP configurations were investigated: H2O2 / UV and H2O2 / UV / O3. From each process samples, COD, phenol and pH were measured. The oxidation was carried out until the targeted phenol concentration of treated effluent were obtained. The better result obtained by using process H2O2 / UV / O3 with the H2O2 concentration 1000 ppm. After 120 minutes, the final target has been achieved in which phenol concentration of 37.5 mg/L or phenol degradation of 93.75%.

Grape juice concentrate modulates p16 expression in high fat diet-induced liver steatosis in Wistar rats.

Science.gov (United States)

Ferreira, Andressa Orlandeli; Gollücke, Andréa Pittelli Boiago; Noguti, Juliana; da Silva, Victor Hugo Pereira; Yamamura, Elsa Tiemi Hojo; Ribeiro, Daniel Araki

2012-04-01

The goal of this study was to investigate whether subchronic treatment with grape juice concentrate is able to protect the liver from high fat diet injury in rats. The effects of grape juice concentrate treatment on histopathological changes, and immunohistochemistry for p53, p16 and p21 were evaluated. Male Wistar rats (n = 18) were distributed into three groups: group 1: negative control; group 2: cholesterol at 1% (w/w) in their diet, treated during 5 weeks; and group 3: cholesterol at 1% in their chow during 5 weeks, and grape juice concentrate at 222 mg per day in their drinking-water in the last week only. The results pointed out that treatment with grape juice concentrate did not show remarkable differences regarding liver tissue in the cholesterol-exposed group when compared to group 2. However, grape juice concentrate was able to modulate p16 immunoexpression when compared to high fat diet group. p53 and p21 did not show any significant statistical differences among groups. Taken together, our results suggest that subchronic grape juice concentrate administration was able to modulate cell cycle control by downregulation of p16 immunoexpression in high fat diet-induced liver steatosis in rats.

IMPLICATIONS ON THE NUMBER AND CONCENTRATION OF SUPPLIERS ON ROMANIAN TRANSPORT SERVICES

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PĂUN IULIAN GABRIEL

2017-02-01

Full Text Available This paper aims to capture the current situation characterizing the transport sector in Romania by degree of concentration of transport service providers. Market analysis covers road, rail and air transport. Knowing the concentration of these markets is useful when it realizes development strategy of these sectors with profound implications on the national economy. There is a decreasing degree of concentration in the road transport sector due to growing number of enterprises in this market. Air transport has similar trend the road transport, the concentration declining during the span of years analyzed. Regarding the Herfindahl-Hirschmann index in the railway sector, we find that it reveals for the year 2012 a very high degree of concentration.

Adverse effects of concentrated green tea extracts.

Science.gov (United States)

Schönthal, Axel H

2011-06-01

A myriad of health claims are being made in favor of the consumption of green tea. However, mostly due to the easy availability and greater than ever popularity of highly concentrated green tea extracts, sometimes combined with an attitude of more-is-better, certain health risks of green tea consumption have begun to emerge. Among such risks are the possibility of liver damage, the potential to interact with prescription drugs to alter their therapeutic efficacy, and the chance to cause harm when combined with other highly popular herbal remedies. This review will summarize documented examples of adverse effects of green tea in humans, and will discuss risks of copious consumption of highly concentrated green tea extracts as indicated by studies in animals. While there is no intention to minimize any of the scientifically established benefits of the use of green tea, the purpose of this review is to focus primarily on the potential for adverse effects and raise awareness of the rare, yet under-appreciated risks. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High concentrations of pepsin in bronchoalveolar lavage fluid from children with cystic fibrosis are associated with high interleukin-8 concentrations.

LENUS (Irish Health Repository)

McNally, P

2012-02-01

BACKGROUND: Gastro-oesophageal reflux is common in children with cystic fibrosis (CF) and is thought to be associated with pulmonary aspiration of gastric contents. The measurement of pepsin in bronchoalveolar lavage (BAL) fluid has recently been suggested to be a reliable indicator of aspiration. The prevalence of pulmonary aspiration in a group of children with CF was assessed and its association with lung inflammation investigated. METHODS: This was a cross-sectional case-control study. BAL fluid was collected from individuals with CF (n=31) and healthy controls (n=7). Interleukin-8 (IL-8), pepsin, neutrophil numbers and neutrophil elastase activity levels were measured in all samples. Clinical, microbiological and lung function data were collected from medical notes. RESULTS: The pepsin concentration in BAL fluid was higher in the CF group than in controls (mean (SD) 24.4 (27.4) ng\\/ml vs 4.3 (4.0) ng\\/ml, p=0.03). Those with CF who had raised pepsin concentrations had higher levels of IL-8 in the BAL fluid than those with a concentration comparable to controls (3.7 (2.7) ng\\/ml vs 1.4 (0.9) ng\\/ml, p=0.004). Within the CF group there was a moderate positive correlation between pepsin concentration and IL-8 in BAL fluid (r=0.48, p=0.04). There was no association between BAL fluid pepsin concentrations and age, sex, body mass index z score, forced expiratory volume in 1 s or Pseudomonas aeruginosa colonisation status. CONCLUSIONS: Many children with CF have increased levels of pepsin in the BAL fluid compared with normal controls. Increased pepsin levels were associated with higher IL-8 concentrations in BAL fluid. These data suggest that aspiration of gastric contents occurs in a subset of patients with CF and is associated with more pronounced lung inflammation.

Unexpectedly high ultrafine aerosol concentrations above East Antarctic sea ice

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R. S. Humphries

2016-02-01

Full Text Available Better characterisation of aerosol processes in pristine, natural environments, such as Antarctica, have recently been shown to lead to the largest reduction in uncertainties in our understanding of radiative forcing. Our understanding of aerosols in the Antarctic region is currently based on measurements that are often limited to boundary layer air masses at spatially sparse coastal and continental research stations, with only a handful of studies in the vast sea-ice region. In this paper, the first observational study of sub-micron aerosols in the East Antarctic sea ice region is presented. Measurements were conducted aboard the icebreaker Aurora Australis in spring 2012 and found that boundary layer condensation nuclei (CN3 concentrations exhibited a five-fold increase moving across the polar front, with mean polar cell concentrations of 1130 cm−3 – higher than any observed elsewhere in the Antarctic and Southern Ocean region. The absence of evidence for aerosol growth suggested that nucleation was unlikely to be local. Air parcel trajectories indicated significant influence from the free troposphere above the Antarctic continent, implicating this as the likely nucleation region for surface aerosol, a similar conclusion to previous Antarctic aerosol studies. The highest aerosol concentrations were found to correlate with low-pressure systems, suggesting that the passage of cyclones provided an accelerated pathway, delivering air masses quickly from the free troposphere to the surface. After descent from the Antarctic free troposphere, trajectories suggest that sea-ice boundary layer air masses travelled equatorward into the low-albedo Southern Ocean region, transporting with them emissions and these aerosol nuclei which, after growth, may potentially impact on the region's radiative balance. The high aerosol concentrations and their transport pathways described here, could help reduce the discrepancy currently present between

Unexpectedly high ultrafine aerosol concentrations above East Antarctic sea ice

Science.gov (United States)

Humphries, R. S.; Klekociuk, A. R.; Schofield, R.; Keywood, M.; Ward, J.; Wilson, S. R.

2016-02-01

Better characterisation of aerosol processes in pristine, natural environments, such as Antarctica, have recently been shown to lead to the largest reduction in uncertainties in our understanding of radiative forcing. Our understanding of aerosols in the Antarctic region is currently based on measurements that are often limited to boundary layer air masses at spatially sparse coastal and continental research stations, with only a handful of studies in the vast sea-ice region. In this paper, the first observational study of sub-micron aerosols in the East Antarctic sea ice region is presented. Measurements were conducted aboard the icebreaker Aurora Australis in spring 2012 and found that boundary layer condensation nuclei (CN3) concentrations exhibited a five-fold increase moving across the polar front, with mean polar cell concentrations of 1130 cm-3 - higher than any observed elsewhere in the Antarctic and Southern Ocean region. The absence of evidence for aerosol growth suggested that nucleation was unlikely to be local. Air parcel trajectories indicated significant influence from the free troposphere above the Antarctic continent, implicating this as the likely nucleation region for surface aerosol, a similar conclusion to previous Antarctic aerosol studies. The highest aerosol concentrations were found to correlate with low-pressure systems, suggesting that the passage of cyclones provided an accelerated pathway, delivering air masses quickly from the free troposphere to the surface. After descent from the Antarctic free troposphere, trajectories suggest that sea-ice boundary layer air masses travelled equatorward into the low-albedo Southern Ocean region, transporting with them emissions and these aerosol nuclei which, after growth, may potentially impact on the region's radiative balance. The high aerosol concentrations and their transport pathways described here, could help reduce the discrepancy currently present between simulations and observations of

The effect of extremely high glucose concentrations on 21 routine chemistry and thyroid Abbott assays: interference study.

Science.gov (United States)

Çuhadar, Serap; Köseoğlu, Mehmet; Çinpolat, Yasemin; Buğdaycı, Güler; Usta, Murat; Semerci, Tuna

2016-01-01

Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L. Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically. Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference. Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.

High Pb concentration stress on Typha latifolia growth and Pb removal in microcosm wetlands.

Science.gov (United States)

Han, Jianqiu; Chen, Fengzhen; Zhou, Yumei; Wang, Chaohua

2015-01-01

When constructed wetlands are used to treat high-Pb wastewater, Pb may become a stress to wetland plants, which subsequently reduces treatment performance and the other ecosystem services. To facilitate the design and operation of constructed wetlands for treatment of Pb-rich wastewater, we investigated the irreversible inhibitory level of Pb for Typha latifolia through experiments in microcosm wetlands. Seven horizontal subsurface flow constructed wetlands were built with rectangular plastic tanks and packed with marble chips and sand. All wetlands were transplanted with nine stems of Typha latifolia each. The wetlands were batch operated in a greenhouse with artificial wastewater (10 L each) for 12 days. Influent to the seven wetlands had different concentrations of Pb: 0 mg/L, 10 mg/L, 25 mg/L, 50 mg/L, 100 mg/L, 200 mg/L, and 500 mg/L, respectively. The results suggested that leaf chlorophyll relative content, relative growth rate, photosynthetic characteristics, activities of superoxide dismutase, peroxidase, and content of malondialdehyde were not affected when initial Pb concentration was at 100 mg/L and below. But when initial Pb concentration was above 100 mg/L, all of them were seriously affected. We conclude that high Pb concentrations wastewater could inhibit the growth of Typha latifolia and decrease the removal rate of wetlands.

Radon concentrations in drinking water in Wakasa area, Fukui Prefecture

Energy Technology Data Exchange (ETDEWEB)

Tokuyama, Hideki; Igarashi, Shuichi [Fukui Prefectural Environmental Radiation Research and Monitoring Center, Tsuruga (Japan)

1997-02-01

Radon concentration in drinking water was surveyed to make basic data for the investigation of radiation dose due to natural radioisotopes in the general public. Here, the survey data in the Wakasa region were reported. Sampling was carried out at 126 points in this region (ca. 70x50 km{sup 2}). A total of 167 samples were taken from the tap of private wells, and small and large public water supplies. The radon concentration was determined by direct measuring method. The mean concentration of ground water from the wells was 28.5 Bq/l, significantly higher than those of the tap water from small and large water supplies, 5.0 and 11.2 Bq/l, respectively. Rn concentration of ground water was dependent on geological features and it was comparatively high in the granite region. Ground water containing a high concentration of Rn was mixed into the water of some large water supply in the cities, showing that its Rn concentration was higher compared to those for the small water supply. This survey was conducted only in the winter seasons from 1989 to 1993. Therefore, there are no data concerning seasonal changes in Rn concentration to drinking water. (M.N.)

High-Thermal- and Air-Stability Cathode Material with Concentration-Gradient Buffer for Li-Ion Batteries.

Science.gov (United States)

Shi, Ji-Lei; Qi, Ran; Zhang, Xu-Dong; Wang, Peng-Fei; Fu, Wei-Gui; Yin, Ya-Xia; Xu, Jian; Wan, Li-Jun; Guo, Yu-Guo

2017-12-13

Delivery of high capacity with high thermal and air stability is a great challenge in the development of Ni-rich layered cathodes for commercialized Li-ion batteries (LIBs). Herein we present a surface concentration-gradient spherical particle with varying elemental composition from the outer end LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM) to the inner end LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA). This cathode material with the merit of NCM concentration-gradient protective buffer and the inner NCA core shows high capacity retention of 99.8% after 200 cycles at 0.5 C. Furthermore, this cathode material exhibits much improved thermal and air stability compared with bare NCA. These results provide new insights into the structural design of high-performance cathodes with high energy density, long life span, and storage stability materials for LIBs in the future.

Determination of the activity concentration levels of the artificial radionuclide137Cs in soil samples collected from Qatar using high-resolution gamma-ray spectrometry

Science.gov (United States)

Al-Sulaiti, Huda; Nasir, Tabassum; Al Mugren, K. S.; Alkhomashi, N.; Al-Dahan, N.; Al-Dosari, M.; Bradley, D. A.; Bukhari, S.; Regan, P. H.; Santawamaitre, T.; Malain, D.; Habib, A.; Al-Dosari, Hanan; Daar, Eman

2016-09-01

The goal of this study was to establish the first baseline measurements for radioactivity concentration of the artificial radionuclide 137Cs in soil samples collected from the Qatarian peninsula. The work focused on the determination of the activity concentrations levels of man-made radiation in 129 soil samples collected across the landscape of the State of Qatar. All the samples were collected before the most recent accident in Japan, “the 2011 Fukushima Dai-ichi nuclear power plant accident”. The activity concentrations have been measured via high-resolution gamma-ray spectrometry using a hyper-pure germanium detector situated in a low-background environment with a copper inner-plated passive lead shield. A radiological map showing the activity concentrations of 137Cs is presented in this work. The concentration wasfound to range from 0.21 to 15.41 Bq/kg. The highest activity concentration of 137Cs was observed in sample no. 26 in North of Qatar. The mean value was found to be around 2.15 ± 0.27 Bq/kg. These values lie within the expected range relative to the countries in the region. It is expected that this contamination is mainly due to the Chernobyl accident on 26 April 1986, but this conclusion cannot be confirmed because of the lack of data before this accident.

High Ice Water Concentrations in the 19 August 2015 Coastal Mesoconvective System

Science.gov (United States)

Proctor, Fred H.; Harrah, Steven; Switzer, George F.; Strickland, Justin K.; Hunt, Patricia J.

2017-01-01

During August 2015, NASA's DC-8 research aircraft was flown into High Ice Water Content (HIWC) events as part of a three-week campaign to collect airborne radar data and to obtain measurements from microphysical probes. Goals for this flight campaign included improved characterization of HIWC events, especially from an airborne radar perspective. This paper focuses on one of the flight days, in which a coastal mesoscale convective system (MCS) was investigated for HIWC conditions. The system appears to have been maintained by bands of convection flowing in from the Gulf of Mexico. These convective bands were capped by a large cloud canopy, which masks the underlying structure if viewed from an infrared sensing satellite. The DC-8 was equipped with an IsoKinetic Probe that measured ice concentrations of up to 2.3 g m(exp -3) within the cloud canopy of this system. Sustained measurements of ice crystals with concentrations exceeding 1 g m(exp -3) were encountered for up to ten minutes of flight time. Airborne Radar reflectivity factors were found to be weak within these regions of high ice water concentrations, suggesting that Radar detection of HIWC would be a challenging endeavor. This case is then investigated using a three-dimensional numerical cloud model. Profiles of ice water concentrations and radar reflectivity factor demonstrate similar magnitudes and scales between the flight measurements and model simulation. Also discussed are recent modifications to the numerical model's ice-microphysics that are based on measurements during the flight campaign. The numerical model and its updated ice-microphysics are further validated with a simulation of a well-known case of a supercell hailstorm measured during the Cooperative Convective Precipitation Experiment. Differences in HIWC between the continental supercell and the coastal MCS are discussed.

Generalization of the Nernst-Einstein equation for self-diffusion in high-defect-concentration solids

International Nuclear Information System (INIS)

McKee, R.A.

1981-01-01

It is shown that the Nernst-Einstein equation can be generalized for a high defect concentration solid to relate the mobility or conductivity to the self-diffusion coefficient. This relationship is derived assuming that the diffusing particles interact strongly and that the mobility is concentration-dependent. It is derived for interstitial disordered structures, but it is perfectly general to any mechanism of self diffusion as long as diffusion in a pure system is considered

Influence of pre-hydration and pharmacogenetics on plasma methotrexate concentration and renal dysfunction following high-dose methotrexate therapy.

Science.gov (United States)

Yanagimachi, Masakatsu; Goto, Hiroaki; Kaneko, Tetsuji; Naruto, Takuya; Sasaki, Koji; Takeuchi, Masanobu; Tanoshima, Reo; Kato, Hiromi; Yokosuka, Tomoko; Kajiwara, Ryosuke; Fujii, Hisaki; Tanaka, Fumiko; Goto, Shoko; Takahashi, Hiroyuki; Mori, Masaaki; Kai, Sumio; Yokota, Shumpei

2013-12-01

High-dose methotrexate therapy (HD-MTX) has been well established for the treatment of childhood acute lymphoblastic leukemia (ALL). The aims of this study were to investigate whether clinical and pharmacogenetic factors influence plasma MTX concentration and renal dysfunction in patients treated with HD-MTX. In a total of 127 courses of HD-MTX in 51 patients with childhood ALL, influence of clinical and pharmacogenetic factors on plasma MTX concentration and HD-MTX-related renal dysfunction was evaluated. Clinical factors included age, gender, duration of HD-MTX continuous-infusion and duration of pre-hydration before HD-MTX. Pharmacogenetic factors included 5 gene polymorphisms within the MTX pathway genes, namely, SLC19A1, MTHFR, ABCC2 and ABCG2. Short duration of pre-hydration before HD-MTX is the most important risk factor for prolonged high MTX concentration (p < 0.001, OR 6.40, 95 % CI 2.39-17.16) and renal dysfunction (p = 0.013, OR 3.15, 95 % CI 1.27-7.80). The T allele at MTHFR C677T was the risk factor for prolonged high MTX concentration (p = 0.009, OR 5.54, 95 % CI 1.54-19.85), but not for renal dysfunction. We found the influence of MTHFR C677T polymorphism on prolonged high MTX concentration. We reconfirmed the importance of adequate pre-hydration before HD-MTX to prevent prolonged high MTX concentration and MTX-related renal dysfunction.

The obtaining a high-grade gadolinium concentrate

International Nuclear Information System (INIS)

Soltysiak, I.; Ozga, W.

1982-01-01

Gadolinium concentrates obtained by the fractional precipitation of lanthanon-potassium double chromates were separated by ion exchange with 0,4 M lactic acid solution in the presence of 0,1 M ammonium nitrate at pH of the medium 2,95-3,4. It was found out, that using the fractional precipitation of lanthanon-potassium double chromates (as the fast and cheap method that does not need special equipment) together with ion exchange separation with lactic acid solution as the eluent gave a highgrade gadolinium concentrate in a quick and economical way. (author)

Effects of the addition of different nitrogen sources in the tequila fermentation process at high sugar concentration.

Science.gov (United States)

Arrizon, J; Gschaedler, A

2007-04-01

To study the effect of the addition of different nitrogen sources at high sugar concentration in the tequila fermentation process. Fermentations were performed at high sugar concentration (170 g l(-1)) using Agave tequilana Weber blue variety with and without added nitrogen from different sources (ammonium sulfate; glutamic acid; a mixture of ammonium sulfate and amino acids) during the exponential phase of growth. All the additions increased the fermentation rate and alcohol efficiency. The level of synthesis of volatile compounds depended on the source added. The concentration of amyl alcohols and isobutanol were decreased while propanol and acetaldehyde concentration increased. The most efficient nitrogen sources for fermentation rate were ammonium sulfate and the mixture of ammonium sulfate and amino acids. The level of volatile compounds produced depended upon types of nitrogen. The synthesis of some volatile compounds increased while others decreased with nitrogen addition. The addition of nitrogen could be a strategy for improving the fermentation rate and efficiency in the tequila fermentation process at high sugar Agave tequilana concentration. Furthermore, the sensory quality of the final product may change because the synthesis of the volatile compounds is modified.

Physiological epidermal growth factor concentrations activate high affinity receptors to elicit calcium oscillations.

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Béatrice Marquèze-Pouey

Full Text Available Signaling mediated by the epidermal growth factor (EGF is crucial in tissue development, homeostasis and tumorigenesis. EGF is mitogenic at picomolar concentrations and is known to bind its receptor on high affinity binding sites depending of the oligomerization state of the receptor (monomer or dimer. In spite of these observations, the cellular response induced by EGF has been mainly characterized for nanomolar concentrations of the growth factor, and a clear definition of the cellular response to circulating (picomolar concentrations is still lacking. We investigated Ca2+ signaling, an early event in EGF responses, in response to picomolar doses in COS-7 cells where the monomer/dimer equilibrium is unaltered by the synthesis of exogenous EGFR. Using the fluo5F Ca2+ indicator, we found that picomolar concentrations of EGF induced in 50% of the cells a robust oscillatory Ca2+ signal quantitatively similar to the Ca2+ signal induced by nanomolar concentrations. However, responses to nanomolar and picomolar concentrations differed in their underlying mechanisms as the picomolar EGF response involved essentially plasma membrane Ca2+ channels that are not activated by internal Ca2+ store depletion, while the nanomolar EGF response involved internal Ca2+ release. Moreover, while the picomolar EGF response was modulated by charybdotoxin-sensitive K+ channels, the nanomolar response was insensitive to the blockade of these ion channels.

Physiological epidermal growth factor concentrations activate high affinity receptors to elicit calcium oscillations.

Science.gov (United States)

Marquèze-Pouey, Béatrice; Mailfert, Sébastien; Rouger, Vincent; Goaillard, Jean-Marc; Marguet, Didier

2014-01-01

Signaling mediated by the epidermal growth factor (EGF) is crucial in tissue development, homeostasis and tumorigenesis. EGF is mitogenic at picomolar concentrations and is known to bind its receptor on high affinity binding sites depending of the oligomerization state of the receptor (monomer or dimer). In spite of these observations, the cellular response induced by EGF has been mainly characterized for nanomolar concentrations of the growth factor, and a clear definition of the cellular response to circulating (picomolar) concentrations is still lacking. We investigated Ca2+ signaling, an early event in EGF responses, in response to picomolar doses in COS-7 cells where the monomer/dimer equilibrium is unaltered by the synthesis of exogenous EGFR. Using the fluo5F Ca2+ indicator, we found that picomolar concentrations of EGF induced in 50% of the cells a robust oscillatory Ca2+ signal quantitatively similar to the Ca2+ signal induced by nanomolar concentrations. However, responses to nanomolar and picomolar concentrations differed in their underlying mechanisms as the picomolar EGF response involved essentially plasma membrane Ca2+ channels that are not activated by internal Ca2+ store depletion, while the nanomolar EGF response involved internal Ca2+ release. Moreover, while the picomolar EGF response was modulated by charybdotoxin-sensitive K+ channels, the nanomolar response was insensitive to the blockade of these ion channels.

Novel technologies for reverse osmosis concentrate treatment: a review.

Science.gov (United States)

Joo, Sung Hee; Tansel, Berrin

2015-03-01

Global water shortages due to droughts and population growth have created increasing interest in water reuse and recycling and, concomitantly, development of effective water treatment processes. Pressured membrane processes, in particular reverse osmosis, have been adopted in water treatment industries and utilities despite the relatively high operational cost and energy consumption. However, emerging contaminants are present in reverse osmosis concentrate in higher concentrations than in the feed water, and have created challenges for treatment of the concentrate. Further, standards and guidelines for assessment and treatment of newly identified contaminants are currently lacking. Research is needed regarding the treatment and disposal of emerging contaminants of concern in reverse osmosis concentrate, in order to develop cost-effective methods for minimizing potential impacts on public health and the environment. This paper reviews treatment options for concentrate from membrane processes. Barriers to emerging treatment options are discussed and novel treatment processes are evaluated based on a literature review. Copyright © 2014 Elsevier Ltd. All rights reserved.

Performance comparison between ethanol phase-change immersion and active water cooling for solar cells in high concentrating photovoltaic system

International Nuclear Information System (INIS)

Wang, Yiping; Wen, Chen; Huang, Qunwu; Kang, Xue; Chen, Miao; Wang, Huilin

2017-01-01

Highlights: • Thermal performances of ethanol phase-change immersion and active water cooling are compared. • Effects of operation parameters on ethanol phase-change immersion are studied. • Optimum filling ratio is 30% for ethanol phase-change immersion cooling system. • Exergy efficiency of ethanol phase-change immersion method increases by 57%. - Abstract: This paper presents an optimized ethanol phase-change immersion cooling method to obtain lower temperature of dense-array solar cells in high concentrating photovoltaic system. The thermal performances of this system were compared with a conventional active water cooling system with minichannels from the perspectives of start-up characteristic, temperature uniformity, thermal resistance and heat transfer coefficient. This paper also explored the influences of liquid filling ratio, absolute pressure and water flow rate on thermal performances. Dense-array LEDs were used to simulate heat power of solar cells worked under high concentration ratios. It can be observed that the optimal filling ratio was 30% in which the thermal resistance was 0.479 °C/W and the heat transfer coefficient was 9726.21 W/(m 2 ·°C). To quantify the quality of energy output of two cooling systems, exergy analysis are conducted and maximum exergy efficiencies were 17.70% and 11.27%, respectively. The experimental results represent an improvement towards thermal performances of ethanol phase-change immersion cooling system due to the reduction in contact thermal resistance. This study improves the operation control and applications for ethanol phase-change immersion cooling technology.

Highly Efficient Green-Emitting Phosphors Ba2Y5B5O17 with Low Thermal Quenching Due to Fast Energy Transfer from Ce3+ to Tb3.

Science.gov (United States)

Xiao, Yu; Hao, Zhendong; Zhang, Liangliang; Xiao, Wenge; Wu, Dan; Zhang, Xia; Pan, Guo-Hui; Luo, Yongshi; Zhang, Jiahua

2017-04-17

This paper demonstrates a highly thermally stable and efficient green-emitting Ba 2 Y 5 B 5 O 17 :Ce 3+ , Tb 3+ phosphor prepared by high-temperature solid-state reaction. The phosphor exhibits a blue emission band of Ce 3+ and green emission lines of Tb 3+ upon Ce 3+ excitation in the near-UV spectral region. The effect of Ce 3+ to Tb 3+ energy transfer on blue to green emission color tuning and on luminescence thermal stability is studied in the samples codoped with 1% Ce 3+ and various concentrations (0-40%) of Tb 3+ . The green emission of Tb 3+ upon Ce 3+ excitation at 150 °C can keep, on average, 92% of its intensity at room temperature, with the best one showing no intensity decreasing up to 210 °C for 30% Tb 3+ . Meanwhile, Ce 3+ emission intensity only keeps 42% on average at 150 °C. The high thermal stability of the green emission is attributed to suppression of Ce 3+ thermal de-excitation through fast energy transfer to Tb 3+ , which in the green-emitting excited states is highly thermally stable such that no lifetime shortening is observed with raising temperature to 210 °C. The predominant green emission is observed for Tb 3+ concentration of at least 10% due to efficient energy transfer with the transfer efficiency approaching 100% for 40% Tb 3+ . The internal and external quantum yield of the sample with Tb 3+ concentration of 20% can be as high as 76% and 55%, respectively. The green phosphor, thus, shows attractive performance for near-UV-based white-light-emitting diodes applications.

Soil dioxin concentrations in Baden-Wuerttemberg

International Nuclear Information System (INIS)

Wolf, D.

1993-01-01

Soil dioxin levels in Baden-Wuerttemberg are generally low. Where high dioxin concentrations have been reported like in Rastatt, Rheinfelden, Crailsheim-Maulach and Eppingen these phenomena are local. Already at less than 100 metres distance, drastically lower concentrations are measured. At 1500 to 2000 metres distance the values are back to the ordinary background level. A programme for detecting sources of emission in the entire state revealed no further sites of heavy contamination. For this assessment of soil dioxin concentrations in Baden-Wuerttemberg 1275 soil samples were used, which is a vast amount also in comparison with nation-wide surveys. The average dioxin content in farmland is about 1 ng I-TEq/kg m T . Soil dioxin concentrations are the higher the greater the density of settlements and industry. In cities they are about three to five times higher than the ubiquitous background concentration. The highest concentrations measured were 5-20 ng I-TE/kg in garden soils in cities. Sewage sludge may be a significant source of dioxin contamination for farmland, far beyond the ubiquitous background concentration. Automobile exhaust gas caused higher soil contamination within 10 m along both sides of the roads as a function of traffic. Because scavengers in gasoline are now prohibited and catalysts are becoming more and more common the rate of additional dioxin and furan contamination due to traffic will decrease. Currently, traffic-related emissions in Baden-Wuerttemberg are well below 2 g I-TEq. (orig./EF) [de

Origin of methane and sources of high concentrations in Los Angeles groundwater

Science.gov (United States)

Kulongoski, Justin; McMahon, Peter B.; Land, Michael; Wright, Michael; Johnson, Theodore; Landon, Matthew K.

2018-01-01

In 2014, samples from 37 monitoring wells at 17 locations, within or near oil fields, and one site >5 km from oil fields, in the Los Angeles Basin, California, were analyzed for dissolved hydrocarbon gas isotopes and abundances. The wells sample a variety of depths of an aquifer system composed of unconsolidated and semiconsolidated sediments under various conditions of confinement. Concentrations of methane in groundwater samples ranged from 0.002 to 150 mg/L—some of the highest concentrations reported in a densely populated urban area. The δ13C and δ2H of the methane ranged from −80.8 to −45.5 per mil (‰) and −249.8 to −134.9‰, respectively, and, along with oxidation‐reduction processes, helped to identify the origin of methane as microbial methanogenesis and CO2 reduction as its main formation pathway. The distribution of methane concentrations and isotopes is consistent with the high concentrations of methane in Los Angeles Basin groundwater originating from relatively shallow microbial production in anoxic or suboxic conditions. Source of the methane is the aquifer sediments rather than the upward migration or leakage of thermogenic methane associated with oil fields in the basin.

The role of tin-promoted Pd/MWNTs via the management of carbonaceous species in selective hydrogenation of high concentration acetylene

International Nuclear Information System (INIS)

Esmaeili, Elaheh; Mortazavi, Yadollah; Khodadadi, Abbas Ali; Rashidi, Ali Morad; Rashidzadeh, Mehdi

2012-01-01

Highlights: ► Synthesis of highly active tin-promoted catalysts by polyol method for selective hydrogenation of high concentration of acetylene. ► A positive change in the catalytic activities of tin-promoted catalysts results from distinct geometric and electronic effects. ► Change in the coverage of acetylenic overlayers for different temperature regions corresponds to the change of the number of isolated adsorption sites. ► The isolated adsorption sites are responsible for the enhancement of selectivity to ethylene with increased temperatures, via the management of the carbonaceous species over the catalyst surface. - Abstract: In the present study, Pd/MWNTs are synthesized using polyol process and modified by tin as a promoter for selective hydrogenation of high concentrated acetylene feedstock. Polyol method results in highly dispersed nanoparticles with a depletion of particle size for tin-promoted Pd catalysts as characterized by TEM. Tin promoter plays a considerable role in hydrogenation of pure acetylene stream. This is attributed to formation of Pd 2 Sn structural phase, confirmed by XRD and TPR techniques, composed mainly of intermetallic species. Catalytic behavior of tin-promoted Pd catalysts is affected by geometric and electronic factors which are more pronounced in the case of Sn/Pd = 0.25. A discontinuity in Arrhenius plots for the Sn-promoted catalysts is appeared, which seems to be due to a kinetic factor as a result of change in acetylene coverage on Pd metallic ensembles at low and high temperature ranges. Higher selectivity of the catalysts to ethylene is attributed to the presence of more isolated adsorption sites on the catalyst surface originated from both intermetallic compounds confirmed by XPS and the ones formed via the carbonaceous species upon the acetylene hydrogenation reaction.

In vitro study of relationship between signal intensity and gadolinium-DTPA concentration at high magnetic field strength

International Nuclear Information System (INIS)

Shahbazi-Gahrouei, D.; Williams, M.; Allen, B.J.

2001-01-01

Although gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) has been used as a contrast material in MRI, it is known that the contrast enhancement effect is not uniform for high concentrations of Gd-DTPA. In order to evaluate the proper pulse sequences for dynamic MRI in aqueous solutions of Gd-DTPA, blood samples and melanoma cells, the signal intensity for several concentrations of Gd-DTPA were measured under inversion recovery T 1 -weighted) at high magnetic field strength (7.0 Tesla). For aqueous solutions of Gd-DTPA, signal intensity correlated linearly with the concentration of Gd-DTPA between 0 mmol/L and 4 mmol/L. Using blood and melanoma cells, signal intensity correlated non-linearly with the concentration of Gd-DTPA between 0 mmol/L and 1.5 mmol/L. For concentrations of more than 4 mmol/L in aqueous solutions of Gd-DTPA, 1 mmol/L in blood and 1.5 mmol/L in melanoma, signal intensity decreased with increased Gd-DTPA concentration. Copyright (2001) Blackwell Science Pty Ltd

Emerging industrial processes for low grade rare earth mineral concentrates

International Nuclear Information System (INIS)

Soldenhoff, Karin; Ho, Elizabeth

2015-01-01

Historically rare earth recovery has mainly been derived from the processing of monazite, bastnasite and xenotime containing ores amenable to beneficiation, yielding high grade mineral concentrates. A notable exception is the recovery of heavy rare earths from ionic clays in Southern China. Recently, projects are being proposed to treat a range of mineral concentrates which tend to be lower grade with wide ranging modal mineralogy for rare earths and associated gangue minerals. This has a significant impact on processing routes. This paper discusses processes proposed for emerging rare earth producers and how different projects have responded to particular challenges including: Control of phosphorous due to the presence of xenotime or monazite type minerals; Control of phosphorous due to the presence of rare earth containing apatite; Rare earth recovery from polymetallic ores; Control of radionuclides in rare earth processing, etc.

Analysis of the electrolyte convection inside the concentration boundary layer during structured electrodeposition of copper in high magnetic gradient fields.

Science.gov (United States)

König, Jörg; Tschulik, Kristina; Büttner, Lars; Uhlemann, Margitta; Czarske, Jürgen

2013-03-19

To experimentally reveal the correlation between electrodeposited structure and electrolyte convection induced inside the concentration boundary layer, a highly inhomogeneous magnetic field, generated by a magnetized Fe-wire, has been applied to an electrochemical system. The influence of Lorentz and magnetic field gradient force to the local transport phenomena of copper ions has been studied using a novel two-component laser Doppler velocity profile sensor. With this sensor, the electrolyte convection within 500 μm of a horizontally aligned cathode is presented. The electrode-normal two-component velocity profiles below the electrodeposited structure show that electrolyte convection is induced and directed toward the rim of the Fe-wire. The measured deposited structure directly correlates to the observed boundary layer flow. As the local concentration of Cu(2+) ions is enhanced due to the induced convection, maximum deposit thicknesses can be found at the rim of the Fe-wire. Furthermore, a complex boundary layer flow structure was determined, indicating that electrolyte convection of second order is induced. Moreover, the Lorentz force-driven convection rapidly vanishes, while the electrolyte convection induced by the magnetic field gradient force is preserved much longer. The progress for research is the first direct experimental proof of the electrolyte convection inside the concentration boundary layer that correlates to the deposited structure and reveals that the magnetic field gradient force is responsible for the observed structuring effect.

Concentration-Induced Association in a Protein System Caused by a Highly Directional Patch Attraction.

Science.gov (United States)

Li, Weimin; Persson, Björn A; Lund, Mikael; Bergenholtz, Johan; Zackrisson Oskolkova, Malin

2016-09-01

Self-association of the protein lactoferrin is studied in solution using small-angle X-ray scattering techniques. Effective static structure factors have been shown to exhibit either a monotonic or a nonmonotonic dependence on protein concentration in the small wavevector limit, depending on salt concentration. The behavior correlates with a nonmonotonic dependence of the second virial coefficient on salt concentration, such that a maximum appears in the structure factor at a low protein concentration when the second virial coefficient is negative and close to a minimum. The results are interpreted in terms of an integral equation theory with explicit dimers, formulated by Wertheim, which provides a consistent framework able to explain the behavior in terms of a monomer-dimer equilibrium that appears because of a highly directional patch attraction. Short attraction ranges preclude trimer formation, which explains why the protein system behaves as if it were subject to a concentration-dependent isotropic protein-protein attraction. Superimposing an isotropic interaction, comprising screened Coulomb repulsion and van der Waals attraction, on the patch attraction allows for a semiquantitative modeling of the complete transition pathway from monomers in the dilute limit to monomer-dimer systems at somewhat higher protein concentrations.

Performance and microbial community variations of anaerobic digesters under increasing tetracycline concentrations

KAUST Repository

Xiong, Yanghui; Harb, Moustapha; Hong, Pei-Ying

2017-01-01

The impact of different concentrations of tetracycline on the performance of anaerobic treatment was evaluated. Results revealed that for all of the tested tetracycline concentrations, no major sustained impact on methane production was observed. Instead, a significant increase in propionic acid was observed in the reactor subjected to the highest concentration of tetracycline (20 mg/L). Microbial community analyses suggest that an alternative methanogenic pathway, specifically that of methanol-utilizing methanogens, may be important for ensuring the stability of methane production in the presence of high tetracycline concentrations. In addition, the accumulation of propionate was due to an increase in volatile fatty acids (VFA)-producing bacteria coupled with a reduction in propionate utilizers. An increase in the abundance of tetracycline resistance genes associated with ribosomal protection proteins was observed after 30 days of exposure to high concentrations of tetracycline, while other targeted resistance genes showed no significant changes. These findings suggest that anaerobic treatment processes can robustly treat wastewater with varying concentrations of antibiotics while also deriving value-added products and minimizing the dissemination of associated antibiotic resistance genes.

Performance and microbial community variations of anaerobic digesters under increasing tetracycline concentrations

KAUST Repository

Xiong, Yanghui

2017-04-01

The impact of different concentrations of tetracycline on the performance of anaerobic treatment was evaluated. Results revealed that for all of the tested tetracycline concentrations, no major sustained impact on methane production was observed. Instead, a significant increase in propionic acid was observed in the reactor subjected to the highest concentration of tetracycline (20 mg/L). Microbial community analyses suggest that an alternative methanogenic pathway, specifically that of methanol-utilizing methanogens, may be important for ensuring the stability of methane production in the presence of high tetracycline concentrations. In addition, the accumulation of propionate was due to an increase in volatile fatty acids (VFA)-producing bacteria coupled with a reduction in propionate utilizers. An increase in the abundance of tetracycline resistance genes associated with ribosomal protection proteins was observed after 30 days of exposure to high concentrations of tetracycline, while other targeted resistance genes showed no significant changes. These findings suggest that anaerobic treatment processes can robustly treat wastewater with varying concentrations of antibiotics while also deriving value-added products and minimizing the dissemination of associated antibiotic resistance genes.

Performance and microbial community variations of anaerobic digesters under increasing tetracycline concentrations.

Science.gov (United States)

Xiong, Yanghui; Harb, Moustapha; Hong, Pei-Ying

2017-07-01

The impact of different concentrations of tetracycline on the performance of anaerobic treatment was evaluated. Results revealed that for all of the tested tetracycline concentrations, no major sustained impact on methane production was observed. Instead, a significant increase in propionic acid was observed in the reactor subjected to the highest concentration of tetracycline (20 mg/L). Microbial community analyses suggest that an alternative methanogenic pathway, specifically that of methanol-utilizing methanogens, may be important for ensuring the stability of methane production in the presence of high tetracycline concentrations. In addition, the accumulation of propionate was due to an increase in volatile fatty acids (VFA)-producing bacteria coupled with a reduction in propionate utilizers. An increase in the abundance of tetracycline resistance genes associated with ribosomal protection proteins was observed after 30 days of exposure to high concentrations of tetracycline, while other targeted resistance genes showed no significant changes. These findings suggest that anaerobic treatment processes can robustly treat wastewater with varying concentrations of antibiotics while also deriving value-added products and minimizing the dissemination of associated antibiotic resistance genes.

Diffusion of ion-implanted B in high concentration P- and As-doped silicon

International Nuclear Information System (INIS)

Fair, R.B.; Pappas, P.N.

1975-01-01

The diffusion of ion-implanted B in Si in the presence of a uniform background of high concentration P or As was studied by correlating numerical profile calculations with profiles determined by secondary-ion mass spectrometry (SIMS). Retarded B diffusion is observed in both As- and P-doped Si, consistent with the effect of the local Fermi-level position in the Si band gap on B diffusivity, D/sub B/. It is shown that D/sub B/ is linearly dependent on the free hole concentration, p, over the range 0.1 less than p/n/sub ie/ less than 30, where n/sub ie/ is the effective intrinsic electron concentration. This result does not depend on the way in which the background dopant has been introduced (implantation predeposition or doped-oxide source), nor the type of dopant used (P or As). (U.S.)

High dielectric permittivity elastomers from well-dispersed expanded graphite in low concentrations

DEFF Research Database (Denmark)

Daugaard, Anders Egede; Hassouneh, Suzan Sager; Kostrzewska, Malgorzata

2013-01-01

The development of elastomer materials with a high dielectric permittivity has attracted increased interest over the last years due to their use in for example dielectric electroactive polymers. For this particular use, both the electrically insulating properties - as well as the mechanical...

Atmospheric concentration of 210Pb at Beijing and Chengdu, the People's Republic of China

International Nuclear Information System (INIS)

Sato, Shin; Sato, Jun; Doi, Taeko

2000-01-01

Atmospheric concentrations of 210 Pb were observed in the eastern area of the People's Republic of China with aerosol samples. Observations were carried out intermittently during the period from April, 1989 to December, 1992 at Beijing and Chengdu. The atmospheric concentrations of 210 Pb ranged from 0.9 to 4.6 mBq/m 3 at Beijing and from 1.4 to 7.8 mBq/m 3 at Chengdu, respectively, which were in the similar level to those observed previously in the inland area of the Chinese Continent. Seasonal variations of the 210 Pb concentration show the 'one-peak' variation pattern: the maximum levels were recorded in winter season. Small additional rises in the atmospheric 210 Pb concentrations observed in the period from spring to autumn seasons may be due to complicated meteorology with high pressure systems at Beijing and due to the topographical situation at Chengdu. (author)

Genomic and transcriptomic insights into how bacteria withstand high concentrations of benzalkonium chloride biocides.

Science.gov (United States)

Kim, Minjae; Hatt, Janet K; Weigand, Michael R; Krishnan, Raj; Pavlostathis, Spyros G; Konstantinidis, Konstantinos T

2018-04-13

Benzalkonium chlorides (BAC) are commonly used biocides in broad-spectrum disinfectant solutions. How microorganisms cope with BAC exposure remains poorly understood, despite its importance for disinfection and disinfectant-induced antibiotic resistance. To provide insights into these issues, we exposed two isolates of an opportunistic pathogen, Pseudomonas aeruginosa , to increasing concentrations of BAC. One isolate was pre-adapted to BAC as it originated from a bioreactor fed with sub-inhibitory concentrations of BAC for 3 years, while the other originated from a bioreactor that received no BAC. Replicated populations of both isolates were able to survive high concentrations of BAC, up to 1200 and 1600mg/L for the non- and pre-adapted ones, respectively, exceeding typical application doses. RNA-seq analysis revealed up-regulation of efflux pump genes and decreased expression of porins related to BAC transport as well as reduced growth rate. Increased expression of spermidine (a polycation) synthase genes and mutations in the pmrB (polymyxin resistance) gene, which cause a reduction in membrane negative charge, suggested that a major adaptation to exposure to the cationic surfactant BAC was to actively stabilize cell surface charge. Collectively, these results revealed that P. aeruginosa adapts to BAC exposure by a combination of mechanisms, and provided genetic markers to monitor BAC-resistant organisms that may have applications in the practice of disinfection. Importance Benzalkonium chlorides (BAC) are widely used as biocides in disinfectant solutions, food processing lines, domestic households, and healthcare facilities. Due to their wide use and mode of action, there has been rising concern that BAC may promote antibiotic resistance. Consistently, at least 40 outbreaks have been attributed to infection by disinfectant- and antibiotic-resistant pathogens such as Pseudomonas aeruginosa However, the underlying molecular mechanisms that bacteria deal with BAC

Statistical Analysis Of Heavy Metals Concentration In Watermelon Plants Irrigated By Wastewater

Science.gov (United States)

Khanjani, M. J.; Maghsoudi moud, A. A.; Saffari, V. R.; Hashamipor, S. M.; Soltanizadeh, M.

2008-01-01

Concentration of heavy metals in vegetables irrigated by urban wastewater is a cause of serious concern due to the potentials health problems of consuming contaminated produce. In this study it is tried to model the concentration of heavy metals (Cd, Cr, Cu, Fe,…) as a function of their concentration in watermelon roots and stems. Our study shows there is a good relationship between them for most of collected data. By measuring the concentration in root and stem of watermelon plant samples before harvesting, the concentration of heavy metal in watermelon's fruit can be estimated by presented mathematical models. This study shows the concentrations of heavy metals in fruits, roots and stems of watermelon plants are very high and in dangerous level when irrigated by municipal waste water.

Influence of land use on metal concentrations in playa sediments and amphibians in the Southern High Plains

Energy Technology Data Exchange (ETDEWEB)

Venne, Louise S. [Department of Environmental Toxicology, Institute of Environmental and Human Health, Texas Tech University, MS 1163, Lubbock, TX 79409 (United States)]. E-mail: louise.venne@tiehh.ttu.edu; Cobb, George P. [Department of Environmental Toxicology, Institute of Environmental and Human Health, Texas Tech University, MS 1163, Lubbock, TX 79409 (United States); Coimbatore, Gopal [Department of Environmental Toxicology, Institute of Environmental and Human Health, Texas Tech University, MS 1163, Lubbock, TX 79409 (United States); Smith, Loren M. [Wildlife and Fisheries Management Institute, Texas Tech University, MS 2125, Lubbock, TX 79409 (United States); McMurry, Scott T. [Department of Environmental Toxicology, Institute of Environmental and Human Health, Texas Tech University, MS 1163, Lubbock, TX 79409 (United States)

2006-11-15

The Southern High Plains (SHP) is a semi-arid region in which playa wetlands are the focal points of biodiversity. Playas are highly influenced by surrounding land use. Most of the SHP is in agricultural production (primarily cotton) with a history of arsenic-containing herbicide use. Metals influence reproduction and development in amphibians. We analyzed metal residues in playa sediment and whole body tissue of Spea spp. and Bufo cognatus metamorphs from two land uses: cropland and native grassland. Cd and Ni concentrations in B. cognatus tissues differed between land uses. Metal concentrations in Spea spp. tissues did not differ between land uses. Ba was higher in Spea spp. than B. cognatus collected from the same grassland playas, indicating differential habitat use. No correlations between sediment and tissue concentrations were found. Land use appeared to have little influence on metal concentrations and levels were below those known to cause effects in amphibians. - Land use surrounding playas has little effect on metal concentrations in sediments.

Technical note: False low turbidity readings from optical probes during high suspended-sediment concentrations

Science.gov (United States)

Voichick, Nicholas; Topping, David; Griffiths, Ronald

2018-01-01

Turbidity, a measure of water clarity, is monitored for a variety of purposes including (1) to help determine whether water is safe to drink, (2) to establish background conditions of lakes and rivers and detect pollution caused by construction projects and stormwater discharge, (3) to study sediment transport in rivers and erosion in catchments, (4) to manage siltation of water reservoirs, and (5) to establish connections with aquatic biological properties, such as primary production and predator–prey interactions. Turbidity is typically measured with an optical probe that detects light scattered from particles in the water. Probes have defined upper limits of the range of turbidity that they can measure. The general assumption is that when turbidity exceeds this upper limit, the values of turbidity will be constant, i.e., the probe is pegged; however, this assumption is not necessarily valid. In rivers with limited variation in the physical properties of the suspended sediment, at lower suspended-sediment concentrations, an increase in suspended-sediment concentration will cause a linear increase in turbidity. When the suspended-sediment concentration in these rivers is high, turbidity levels can exceed the upper measurement limit of an optical probe and record a constant pegged value. However, at extremely high suspended-sediment concentrations, optical turbidity probes do not necessarily stay pegged at a constant value. Data from the Colorado River in Grand Canyon, Arizona, USA, and a laboratory experiment both demonstrate that when turbidity exceeds instrument-pegged conditions, increasing suspended-sediment concentration (and thus increasing turbidity) may cause optical probes to record decreasing false turbidity values that appear to be within the valid measurement range of the probe. Therefore, under high-turbidity conditions, other surrogate measurements of turbidity (e.g., acoustic-attenuation measurements or suspended-sediment samples

Time-dependent 2-D modeling of edge plasma transport with high intermittency due to blobs

International Nuclear Information System (INIS)

Pigarov, A. Yu.; Krasheninnikov, S. I.; Rognlien, T. D.

2012-01-01

The results on time-dependent 2-D fluid modeling of edge plasmas with non-diffusive intermittent transport across the magnetic field (termed cross-field) based on the novel macro-blob approach are presented. The capability of this approach to simulate the long temporal evolution (∼0.1 s) of the background plasma and simultaneously the fast spatiotemporal dynamics of blobs (∼10 −4 s) is demonstrated. An analysis of a periodic sequence of many macro-blobs (PSMB) is given showing that the resulting plasma attains a dynamic equilibrium. Plasma properties in the dynamic equilibrium are discussed. In PSMB modeling, the effect of macro-blob generation frequency on edge plasma parameters is studied. Comparison between PSMB modeling and experimental profile data is given. The calculations are performed for the same plasma discharge using two different models for anomalous cross-field transport: time-average convection and PSMB. Parametric analysis of edge plasma variation with transport coefficients in these models is presented. The capability of the models to accurately simulate enhanced transport due to blobs is compared. Impurity dynamics in edge plasma with macro-blobs is also studied showing strong impact of macro-blob on profiles of impurity charge states caused by enhanced outward transport of high-charge states and simultaneous inward transport of low-charge states towards the core. Macro-blobs cause enhancement of sputtering rates, increase radiation and impurity concentration in plasma, and change erosion/deposition patterns.

High-energy ion tail formation due to ion acoustic turbulence in the TRIAM-1 tokamak

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Kazuo; Hiraki, Naoji; Nakamura, Yukio; Itoh, Satoshi [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics

1982-02-01

The two-component ion energy spectra observed in the TRIAM-1 tokamak are explained as a result of the high-energy ion tail formation due to ion acoustic turbulence driven by a toroidal current pulse for turbulent heating.

Bioleaching of pollymetallic sulphide concentrate using thermophilic bacteria

Directory of Open Access Journals (Sweden)

Vuković Milovan

2014-01-01

Full Text Available An extreme thermophilic, iron-sulphur oxidising bacterial culture was isolated and adapted to tolerate high metal and solids concentrations at 70°C. Following isolation and adaptation, the culture was used in a batch bioleach test employing a 5-l glass standard magnetic agitated and aerated reactor, for the bioleaching of a copper-lead-zinc collective concentrate. The culture exhibited stable leach performance over the period of leach operation and overall copper and zinc extractions higher than 97%. Lead sulphide is transformed into lead sulphate remaining in the bioleach residue due to the low solubility in sulphate media. Brine leaching of bioleach residue yields 95% lead extraction. [Projekat Ministarstva nauke Republike Srbije, br. 34023

Atmospheric fate of poly- and perfluorinated alkyl substances (PFASs): I. Day–night patterns of air concentrations in summer in Zurich, Switzerland

International Nuclear Information System (INIS)

Müller, Claudia E.; Gerecke, Andreas C.; Bogdal, Christian; Wang, Zhanyun; Scheringer, Martin; Hungerbühler, Konrad

2012-01-01

Poly- and perfluorinated alkyl substances (PFASs) are anthropogenic pollutants ubiquitously found in the environment. Volatile PFASs are likely transported atmospherically over long ranges, but identification and quantification of emission sources is a challenging task. In this work, special meteorological conditions were utilized to quantify atmospheric emissions of Zurich City, Switzerland with a dual approach of modeling and field measurements. During high pressure systems in summer, a stable nocturnal boundary layer is formed in which pollutants are enriched. For volatile PFASs, a diel pattern of high concentrations in the night and low concentrations during the day was observed in Zurich, which is likely due to the atmospheric boundary layer dynamics. These results enable to model the emission source strength of Zurich City with a multimedia mass balance model in an accompanying paper. Cluster analyses suggested that perfluorocarboxylates (PFCAs) are a result of degradation of volatile precursors and direct emissions. - Highlights: ► Atmospheric PFAS concentrations in Zurich increase during the night. ► Diel concentration dynamics are likely due to stable nocturnal boundary layer. ► City is a source of PFASs to the atmosphere. ► 8:2 FTOH concentrations are high: up to 1200 pg/m 3 . ► PFAA concentrations are correlated with ozone, not particulate matter. - Semivolatile PFAS concentrations follow a diel trend in Zurich City in stable summer conditions likely due to atmospheric boundary layer effects and urban emissions.

Surgeon Design Interface for Patient-Specific Concentric Tube Robots.

Science.gov (United States)

Morimoto, Tania K; Greer, Joseph D; Hsieh, Michael H; Okamura, Allison M

2016-06-01

Concentric tube robots have potential for use in a wide variety of surgical procedures due to their small size, dexterity, and ability to move in highly curved paths. Unlike most existing clinical robots, the design of these robots can be developed and manufactured on a patient- and procedure-specific basis. The design of concentric tube robots typically requires significant computation and optimization, and it remains unclear how the surgeon should be involved. We propose to use a virtual reality-based design environment for surgeons to easily and intuitively visualize and design a set of concentric tube robots for a specific patient and procedure. In this paper, we describe a novel patient-specific design process in the context of the virtual reality interface. We also show a resulting concentric tube robot design, created by a pediatric urologist to access a kidney stone in a pediatric patient.

Acquisition and Analysis of Data from High Concentration Solutions

KAUST Repository

Besong, Tabot M.D.

2016-05-13

The problems associated with ultracentrifugal analysis of macromolecular solutions at high (>10 mg/ml) are reviewed. Especially for the case of solutes which are non-monodisperse, meaningful results are not readily achievable using sedimentation velocity approaches. It is shown however by both simulation and analysis of practical data that using a modified form of an algorithm (INVEQ) published in other contexts, sedimentation equilibrium (SE) profiles can be analysed successfully, enabling topics such as oligomer presence or formation to be defined.To achieve this, it is necessary to employ an approach in which the solution density, which in an SE profile is radius-dependent, is taken into consideration. Simulation suggests that any reasonable level of solute concentration can be analysed.

Acquisition and Analysis of Data from High Concentration Solutions

KAUST Repository

Besong, Tabot M.D.; Rowe, Arthur J.

2016-01-01

The problems associated with ultracentrifugal analysis of macromolecular solutions at high (>10 mg/ml) are reviewed. Especially for the case of solutes which are non-monodisperse, meaningful results are not readily achievable using sedimentation velocity approaches. It is shown however by both simulation and analysis of practical data that using a modified form of an algorithm (INVEQ) published in other contexts, sedimentation equilibrium (SE) profiles can be analysed successfully, enabling topics such as oligomer presence or formation to be defined.To achieve this, it is necessary to employ an approach in which the solution density, which in an SE profile is radius-dependent, is taken into consideration. Simulation suggests that any reasonable level of solute concentration can be analysed.

Consideration on the delay of radiocesium concentration decrease in bamboo shoots

International Nuclear Information System (INIS)

Tagami, Keiko; Uchida, Shigeo

2012-01-01

After the large releases of radionuclides due to the nuclear power plant accident in March 2011, trees in wide areas were directly contaminated. The contaminated leaves (mostly ever green trees) fell in the late spring to early summer, newly emerged leaves contained some radiocesium which were translocated from tree branches and trunks, and from soil through roots. The concentrations of radiocesium in tree leaves are decreasing due to dilution effect. However, for the case of bamboo shoots, decrease in radiocesium concentration was not observed in some areas when 2011 and 2012 samples were compared. In order to understand the fate of radiocesium in bamboos, 137 Cs concentration changes in leaves and branches from bamboos and litter layer and soil samples in a bamboo forest were measured. It was found that the concentration was higher in the following order: litter > leaves > branches > soil on 9 May 2011, however, the order changed to litter > soil >> leaves, branches on 20 October 2011. Removal of contaminated leaves from the bamboo trees and decomposition of the litter layer to soil organic matter was suggested from the results. Since the root zone of bamboo shoots was in the soil organic layer, radiocesium was taken up through roots to the shoots, and thus the concentration would be high. (author)

Estimation of annual effective dose from 226Ra 228Ra due to consumption of foodstuffs by inhabitants of high level natural radiation of Ramsar, Iran

International Nuclear Information System (INIS)

Fathivand, A.A.; Asefi, M.; Amidi, A.

2005-01-01

Full text: A knowledge of natural radioactivity in man and his environment is important since naturally occurring radionuclides are the major source of radiation exposure to man. Radioactive nuclides present in the natural environment enter the human body mainly through food and water.Besides, measurement of naturally occurring radionuclides in the environment can be used not only as a reference when routine releases from nuclear installation or accidental radiation exposures are assessed, but also as a baseline to evaluate the impact caused by non-nuclear activities. In Iran, measurement of natural and artificial radionuclides in environmental samples in normal and high-background radiation areas have been performed by some investigators but no information has been available on 226 Ra and 228 Ra in foodstuffs. Therefore we have started measurements of 226 Ra and 228 Ra in foodstuffs of Ramsar which is a coastal city in the north part of Iran and has been known as one of the world's high level natural radiation areas, using low level gamma spectrometry measurement system .The results from our measurements and food consumption rates for inhabitants of Ramsar city have been used for the estimation of annual effective dose due to consumption of foodstuffs by inhabitants of Ramsar city. A total of 33 samples from 11 different foodstuffs including root vegetables (beetroot), leafy vegetables (lettuce, parsley and spinach) and tea, meat,chicken, pea,broad bean, rice, and cheese were purchased from markets and were analyzed for their 226 Ra and 228 Ra concentrations. The highest concentrations of 226 Ra and 228 Ra were determined in tea samples with 1570 and 1140 mBq kg -1 respectively and the maximum estimated annual effective dose from 226 Ra and Ra due to consumption foodstuffs were determined to be 19.22 and 0.71 μSv from rice and meat samples respectively

Solution Behavior and Activity of a Halophilic Esterase under High Salt Concentration

Science.gov (United States)

Rao, Lang; Zhao, Xiubo; Pan, Fang; Li, Yin; Xue, Yanfen; Ma, Yanhe; Lu, Jian R.

2009-01-01

Background Halophiles are extremophiles that thrive in environments with very high concentrations of salt. Although the salt reliance and physiology of these extremophiles have been widely investigated, the molecular working mechanisms of their enzymes under salty conditions have been little explored. Methodology/Principal Findings A halophilic esterolytic enzyme LipC derived from archeaon Haloarcula marismortui was overexpressed from Escherichia coli BL21. The purified enzyme showed a range of hydrolytic activity towards the substrates of p-nitrophenyl esters with different alkyl chains (n = 2−16), with the highest activity being observed for p-nitrophenyl acetate, consistent with the basic character of an esterase. The optimal esterase activities were found to be at pH 9.5 and [NaCl] = 3.4 M or [KCl] = 3.0 M and at around 45°C. Interestingly, the hydrolysis activity showed a clear reversibility against changes in salt concentration. At the ambient temperature of 22°C, enzyme systems working under the optimal salt concentrations were very stable against time. Increase in temperature increased the activity but reduced its stability. Circular dichroism (CD), dynamic light scattering (DLS) and small angle neutron scattering (SANS) were deployed to determine the physical states of LipC in solution. As the salt concentration increased, DLS revealed substantial increase in aggregate sizes, but CD measurements revealed the maximal retention of the α-helical structure at the salt concentration matching the optimal activity. These observations were supported by SANS analysis that revealed the highest proportion of unimers and dimers around the optimal salt concentration, although the coexistent larger aggregates showed a trend of increasing size with salt concentration, consistent with the DLS data. Conclusions/Significance The solution α-helical structure and activity relation also matched the highest proportion of enzyme unimers and dimers. Given that

Characterization of gypsum crystals exposed to a high CO2 concentration fog using x-ray

International Nuclear Information System (INIS)

Carreño-Márquez, I. J. A.; Castillo-Sandoval, I.; Esparza-Ponce, H. E.; Fuentes-Cobas, L.; Montero-Cabrera, M. E.

2015-01-01

In Chihuahua State, a little town called Naica has the largest gypsum single crystals in the world. The growth of these structures has been described as a long and stable process developed over thousands of years. Due to the change in the environmental conditions, these crystals could suffer alterations on their surface. In this project we study the cause of possible deterioration of the giant crystals and intend to suggest measures for their preservation. For this sake, our first experiment consists on several gypsum crystals that have been subjected in a climate chamber to a fog at high CO 2 concentration and 51 °C for a period of time of six months, extracting two crystals every 15 days. Then the crystals have been characterized through Grazing Incidence X-Ray Diffraction using a diffractometer PanAlytical X’PertPro with two different detectors; Xe-filled proportional detector and a Pixel 3D detector. The results were compared to determine which technique is the most suitable to study the degradation of gypsum single crystals. In the two cases, we have identified only the gypsum phase, but with different crystal plane orientations

High concentrations of H2O2 make aerobic glycolysis energetically more favourable than cellular respiration.

Directory of Open Access Journals (Sweden)

Hamid R Molavian

2016-08-01

Full Text Available Since the original observation of the Warburg Effect in cancer cells, over eight decades ago, the major question of why aerobic glycolysis is favored over oxidative phosphorylation has remained unresolved. An understanding of this phenomenon may well be the key to the development of more effective cancer therapies. In this paper, we use a semi-empirical method to throw light on this puzzle. We show that aerobic glycolysis is in fact energetically more favorable than oxidative phosphorylation for concentrations of peroxide (H2O2 above some critical threshold value. The fundamental reason for this is the activation and high engagement of the pentose phosphate pathway (PPP in response to the production of reactive oxygen species H2O2 by mitochondria and the high concentration of H2O2 (produced by mitochondria and other sources. This makes oxidative phosphorylation an inefficient source of energy since it leads (despite high levels of ATP production to a concomitant high energy consumption in order to respond to the hazardous waste products resulting from cellular processes associated with this metabolic pathway. We also demonstrate that the high concentration of H2O2 results in an increased glucose consumption, and also increases the lactate production in the case of glycolysis.

High-Frequency Oscillations Recorded on the Scalp of Patients With Epilepsy Using Tripolar Concentric Ring Electrodes.

Science.gov (United States)

Besio, Walter G; Martínez-Juárez, Iris E; Makeyev, Oleksandr; Gaitanis, John N; Blum, Andrew S; Fisher, Robert S; Medvedev, Andrei V

2014-01-01

Epilepsy is the second most prevalent neurological disorder ([Formula: see text]% prevalence) affecting [Formula: see text] million people worldwide with up to 75% from developing countries. The conventional electroencephalogram is plagued with artifacts from movements, muscles, and other sources. Tripolar concentric ring electrodes automatically attenuate muscle artifacts and provide improved signal quality. We performed basic experiments in healthy humans to show that tripolar concentric ring electrodes can indeed record the physiological alpha waves while eyes are closed. We then conducted concurrent recordings with conventional disc electrodes and tripolar concentric ring electrodes from patients with epilepsy. We found that we could detect high frequency oscillations, a marker for early seizure development and epileptogenic zone, on the scalp surface that appeared to become more narrow-band just prior to seizures. High frequency oscillations preceding seizures were present in an average of 35.5% of tripolar concentric ring electrode data channels for all the patients with epilepsy whose seizures were recorded and absent in the corresponding conventional disc electrode data. An average of 78.2% of channels that contained high frequency oscillations were within the seizure onset or irritative zones determined independently by three epileptologists based on conventional disc electrode data and videos.

Characterization of blood donors with high haemoglobin concentration

DEFF Research Database (Denmark)

Magnussen, K; Hasselbalch, H C; Ullum, H

2013-01-01

Background and Objectives  The literature contains little on the prevalence and causes of high predonation haemoglobin levels among blood donors. This study aimed to characterize and develop an algorithm to manage would-be donors with polycythaemia. Materials and Methods  Between November 2009...... and November 2011, we offered haematology consultations to blood donors with repeated haemoglobin concentration (Hb) above the WHO limit for polycythaemia vera (PV) (10·2 and 11·5 mm/16·5 and 18·5 g/dl for women and men, respectively). Investigation of such donors included Hb, haematocrit, mean cell volume......, erythropoietin, ferritin, platelet count and leucocyte count, JAK2 V617 and JAK2 exon12 analysis, as well as other routine measurements. Results  Among 46 such donors, 39 had a history of smoking, which contributes to erythrocytosis. Two had PV, five had severe hypertension, one of them because of renal artery...

Effects of concentration, head group, and structure of surfactants on the degradation of phenanthrene

International Nuclear Information System (INIS)

Jin Danyue; Jiang Xia; Jing Xin; Ou Ziqing

2007-01-01

The effects of concentration, polar/ionic head group, and structure of surfactants on the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in the aqueous phase, as well as their effects on the bacterial activity were investigated. The toxicity ranking of studied surfactants is: non-ionic surfactants (Tween 80, Brij30, 10LE and Brij35) -1 ) served the sole carbon and energy resource. However, the degradation of 14 C-phenanthrene showed either a decrease or no obvious change with the surfactants present at all tested concentrations (5-40 mg L -1 ). Thus, the surfactant addition is not beneficial to the removal of phenanthrene or other PAH contaminants due presumably to the preferential utilization of surfactants at low levels as the non-toxic nutrient resource and to the high toxicity of the surfactants at high levels to the microorganism activity. Biodegradation of phenanthrene was also influenced by the surfactant concentration, head group type, and structure. Much more research has yet to be completed on the use of surfactants for soil remediation due to the surfactant toxicity or biodegradation effect

Enhanced Enzymatic Production of Cephalexin at High Substrate Concentration with in situ Product Removal by Complexation

Directory of Open Access Journals (Sweden)

Dengchao Li

2008-01-01

Full Text Available Cephalexin (CEX was synthesized with 7-amino-3-deacetoxycephalosporanic acid (7-ADCA and D(–-phenylglycine methyl ester (PGME using immobilized penicillin G acylase from Escherichia coli. It was found that substrate concentration and in situ product could remarkably influence the ratio of synthesis to hydrolysis (S/H and the efficiency of CEX synthesis. The optimal ratio of enzyme to substrate was 65 IU/mM 7-ADCA. High substrate concentration improved the 7-ADCA conversion from 61 to 81 % in the process without in situ product removal (ISPR, while in the synthetic process with ISPR, high substrate concentration increased the 7-ADCA conversion from 88 to 98 %. CEX was easily separated from CEX/β-naphthol complex and its purity and overall yield were 99 and 70 %, respectively.

Decondensation behavior of DNA chains induced by multivalent cations at high salt concentrations: Molecular dynamics simulations and experiments

International Nuclear Information System (INIS)

Jiang Yang-Wei; Zhang Lin-Xi; Ran Shi-Yong; He Lin-Li; Wang Xiang-Hong

2015-01-01

Using molecular dynamics simulations and atomic force microscopy (AFM), we study the decondensation process of DNA chains induced by multivalent cations at high salt concentrations in the presence of short cationic chains in solutions. The typical simulation conformations of DNA chains with varying salt concentrations for multivalent cations imply that the concentration of salt cations and the valence of multivalent cations have a strong influence on the process of DNA decondensation. The DNA chains are condensed in the absence of salt or at low salt concentrations, and the compacted conformations of DNA chains become loose when a number of cations and anions are added into the solution. It is explicitly demonstrated that cations can overcompensate the bare charge of the DNA chains and weaken the attraction interactions between the DNA chains and short cationic chains at high salt concentrations. The condensation-decondensation transitions of DNA are also experimentally observed in mixing spermidine with λ-phage DNA at different concentrations of NaCl/MgCl 2 solutions. (paper)

Unexpectedly high ultrafine aerosol concentrations above East Antarctic sea-ice

Science.gov (United States)

Humphries, R. S.; Klekociuk, A. R.; Schofield, R.; Keywood, M.; Ward, J.; Wilson, S. R.

2015-10-01

The effect of aerosols on clouds and their radiative properties is one of the largest uncertainties in our understanding of radiative forcing. A recent study has concluded that better characterisation of pristine, natural aerosol processes leads to the largest reduction in these uncertainties. Antarctica, being far from anthropogenic activities, is an ideal location for the study of natural aerosol processes. Aerosol measurements in Antarctica are often limited to boundary layer air-masses at spatially sparse coastal and continental research stations, with only a handful of studies in the sea ice region. In this paper, the first observational study of sub-micron aerosols in the East Antarctic sea ice region is presented. Measurements were conducted aboard the ice-breaker Aurora Australis in spring 2012 and found that boundary layer condensation nuclei (CN3) concentrations exhibited a five-fold increase moving across the Polar Front, with mean Polar Cell concentrations of 1130 cm-3 - higher than any observed elsewhere in the Antarctic and Southern Ocean region. The absence of evidence for aerosol growth suggested that nucleation was unlikely to be local. Air parcel trajectories indicated significant influence from the free troposphere above the Antarctic continent, implicating this as the likely nucleation region for surface aerosol, a similar conclusion to previous Antarctic aerosol studies. The highest aerosol concentrations were found to correlate with low pressure systems, suggesting that the passage of cyclones provided an accelerated pathway, delivering air-masses quickly from the free-troposphere to the surface. After descent from the Antarctic free troposphere, trajectories suggest that sea ice boundary layer air-masses travelled equator-ward into the low albedo Southern Ocean region, transporting with them emissions and these aerosol nuclei where, after growth, may potentially impact on the region's radiative balance. The high aerosol concentrations and

Analysis of gold and silver concentration on gold mining tailings by neutron activation analysis

International Nuclear Information System (INIS)

Sadikov, I.I.; Salimov, M.I.; Sadykova, Z.O.

2014-01-01

Full text: Instrumental neutron-activation analysis without radiochemical separation is one of most applicable and often used methods to analyze the concentration of gold, silver and other rare and noble metals in gold ores. This method is not suitable for analyzing low concentration of gold and silver in gold mining tailings due to rather high concentration of some elements. Samples are dissolved by boiling in a mixture of concentrated hydrochloric and nitric acids to extract gold and silver into the solution. Chemical yield of gold and silver after dissolution of the sample and further chromatographic separation is between 92 and 95 percent respectively

Preservation of high glycolytic phenotype by establishing new acute lymphoblastic leukemia cell lines at physiologic oxygen concentration.

Science.gov (United States)

Sheard, Michael A; Ghent, Matthew V; Cabral, Daniel J; Lee, Joanne C; Khankaldyyan, Vazgen; Ji, Lingyun; Wu, Samuel Q; Kang, Min H; Sposto, Richard; Asgharzadeh, Shahab; Reynolds, C Patrick

2015-05-15

Cancer cells typically exhibit increased glycolysis and decreased mitochondrial oxidative phosphorylation, and they continue to exhibit some elevation in glycolysis even under aerobic conditions. However, it is unclear whether cancer cell lines employ a high level of glycolysis comparable to that of the original cancers from which they were derived, even if their culture conditions are changed to physiologically relevant oxygen concentrations. From three childhood acute lymphoblastic leukemia (ALL) patients we established three new pairs of cell lines in both atmospheric (20%) and physiologic (bone marrow level, 5%) oxygen concentrations. Cell lines established in 20% oxygen exhibited lower proliferation, survival, expression of glycolysis genes, glucose consumption, and lactate production. Interestingly, the effects of oxygen concentration used during cell line initiation were only partially reversible when established cell cultures were switched from one oxygen concentration to another for eight weeks. These observations indicate that ALL cell lines established at atmospheric oxygen concentration can exhibit relatively low levels of glycolysis and these levels are semi-permanent, suggesting that physiologic oxygen concentrations may be needed from the time of cell line initiation to preserve the high level of glycolysis commonly exhibited by leukemias in vivo. Copyright © 2015. Published by Elsevier Inc.

Concentration determination of urinary metabolites of N,N-dimethylacetamide by high-performance liquid chromatography-tandem mass spectrometry.

Science.gov (United States)

Yamamoto, Shinobu; Matsumoto, Akiko; Yui, Yuko; Miyazaki, Shota; Kumagai, Shinji; Hori, Hajime; Ichiba, Masayoshi

2018-03-27

N,N-Dimethylacetamide (DMAC) is widely used in industry as a solvent. It can be absorbed through human skin. Therefore, it is necessary to determine exposure to DMAC via biological monitoring. However, the precision of traditional gas chromatography (GC) is low due to the thermal decomposition of metabolites in the high-temperature GC injection port. To overcome this problem, we have developed a new method for the simultaneous separation and quantification of urinary DMAC metabolites using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Urine samples were diluted 10-fold in formic acid, and 1-μl aliquots were injected into the LC-MS/MS equipment. A C18 reverse-phase Octa Decyl Silyl (ODS) column was used as the analytical column, and the mobile phase consisted of a mixture of methanol and aqueous formic acid solution. Urinary concentrations of DMAC and its known metabolites (N-hydroxymethyl-N-methylacetamide (DMAC-OH), N-methylacetamide (NMAC), and S- (acetamidomethyl) mercapturic acid (AMMA) ) were determined in a single run. The dynamic ranges of the calibration curves were 0.05-5 mg/l (r≥0.999) for all four compounds. The limits of detection for DMAC, DMAC-OH, NMAC, and AMMA in urine were 0.04, 0.02, 0.05, and 0.02 mg/l, respectively. Within-run accuracies were 96.5%-109.6% with relative standard deviations of precision being 3.43%-10.31%. The results demonstrated that the proposed method could successfully quantify low concentrations of DMAC and its metabolites with high precision. Hence, this method is useful for evaluating DMAC exposure. In addition, this method can be used to examine metabolite behaviors in human bodies after exposure and to select appropriate biomarkers.

Concentration determination of urinary metabolites of N,N-dimethylacetamide by high-performance liquid chromatography-tandem mass spectrometry

Science.gov (United States)

Yamamoto, Shinobu; Matsumoto, Akiko; Yui, Yuko; Miyazaki, Shota; Kumagai, Shinji; Hori, Hajime; Ichiba, Masayoshi

2017-01-01

Objectives: N,N-Dimethylacetamide (DMAC) is widely used in industry as a solvent. It can be absorbed through human skin. Therefore, it is necessary to determine exposure to DMAC via biological monitoring. However, the precision of traditional gas chromatography (GC) is low due to the thermal decomposition of metabolites in the high-temperature GC injection port. To overcome this problem, we have developed a new method for the simultaneous separation and quantification of urinary DMAC metabolites using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Methods: Urine samples were diluted 10-fold in formic acid, and 1-μl aliquots were injected into the LC-MS/MS equipment. A C18 reverse-phase Octa Decyl Silyl (ODS) column was used as the analytical column, and the mobile phase consisted of a mixture of methanol and aqueous formic acid solution. Results: Urinary concentrations of DMAC and its known metabolites (N-hydroxymethyl-N-methylacetamide (DMAC-OH), N-methylacetamide (NMAC), and S- (acetamidomethyl) mercapturic acid (AMMA) ) were determined in a single run. The dynamic ranges of the calibration curves were 0.05-5 mg/l (r≥0.999) for all four compounds. The limits of detection for DMAC, DMAC-OH, NMAC, and AMMA in urine were 0.04, 0.02, 0.05, and 0.02 mg/l, respectively. Within-run accuracies were 96.5%-109.6% with relative standard deviations of precision being 3.43%-10.31%. Conclusions: The results demonstrated that the proposed method could successfully quantify low concentrations of DMAC and its metabolites with high precision. Hence, this method is useful for evaluating DMAC exposure. In addition, this method can be used to examine metabolite behaviors in human bodies after exposure and to select appropriate biomarkers. PMID:29213009

Multiple paths of electron flow to current in microbial electrolysis cells fed with low and high concentrations of propionate

KAUST Repository

Rao, Hari Ananda

2016-03-03

Microbial electrolysis cells (MECs) provide a viable approach for bioenergy generation from fermentable substrates such as propionate. However, the paths of electron flow during propionate oxidation in the anode of MECs are unknown. Here, the paths of electron flow involved in propionate oxidation in the anode of two-chambered MECs were examined at low (4.5 mM) and high (36 mM) propionate concentrations. Electron mass balances and microbial community analysis revealed that multiple paths of electron flow (via acetate/H2 or acetate/formate) to current could occur simultaneously during propionate oxidation regardless of the concentration tested. Current (57–96 %) was the largest electron sink and methane (0–2.3 %) production was relatively unimportant at both concentrations based on electron balances. At a low propionate concentration, reactors supplemented with 2-bromoethanesulfonate had slightly higher coulombic efficiencies than reactors lacking this methanogenesis inhibitor. However, an opposite trend was observed at high propionate concentration, where reactors supplemented with 2-bromoethanesulfonate had a lower coulombic efficiency and there was a greater percentage of electron loss (23.5 %) to undefined sinks compared to reactors without 2-bromoethanesulfonate (11.2 %). Propionate removal efficiencies were 98 % (low propionate concentration) and 78 % (high propionate concentration). Analysis of 16S rRNA gene pyrosequencing revealed the dominance of sequences most similar to Geobacter sulfurreducens PCA and G. sulfurreducens subsp. ethanolicus. Collectively, these results provide new insights on the paths of electron flow during propionate oxidation in the anode of MECs fed with low and high propionate concentrations.

Radon concentration of waters in Greece and Cyprus

Science.gov (United States)

Nikolopoulos, D.; Vogiannis, E.; Louizi, A.

2009-04-01

Radon (222Rn) is a radioactive gas generated by the decay of the naturally occurring 238U series. It is considered very important from radiological point of view, since it is the most significant natural source of human radiation exposure (approximately 50% from all natural sources). Radon is present in soil, rocks, building materials and waters. Through diffusion and convection, radon migrates and emanates to the atmosphere. Outdoors, radon concentrates at low levels (in the order of 10 Bq/m3). However indoors, radon accumulates significantly. It is trivial to observe indoor environments with high radon levels (in the order of 400 Bq/m3 or higher). Radon accumulation indoors, depends on the composition of the underlying soil and rock formation, on building materials, meteorological parameters, ventilation, heating and water use. Although soil and building materials are the most significant radon sources, there have been reported elevated radon concentrations in building structures due to entering water. It is the radon concentrations in the entering water, the volume and the way of water usage, separated or in combination, that result in large amounts of radon in indoor air. Moreover, radon is a factor of stomach radiation burden due to water consumption. This burden is estimated by measurements of radon concentrations in waters. Due to the health impact of radon exposure, the reporting team continuously measures radon. This work focused on the radon concentrations exposure due to water consumption and use in Greece and Cyprus. Various locations in Greece and Cyprus were accessed taking into consideration existing natural radioactivity data (mainly radon in water), however under the restriction of the capability of movement. Radon in water was measured by Alpha Guard (Genitron Ltd) via a special unit (Aqua Kit). This unit consists of a vessel used for forced degassing of radon diluted in water samples, a security vessel used for water drop deposition. Vessels and

Optical performance evaluation of a solar furnace by measuring the highly concentrated solar flux

International Nuclear Information System (INIS)

Lee, Hyunjin; Chai, Kwankyo; Kim, Jongkyu; Lee, Sangnam; Yoon, Hwanki; Yu, Changkyun; Kang, Yongheack

2014-01-01

We evaluated optical performance of a solar furnace in the KIER (Korea Institute of Energy Research) by measuring the highly concentrated solar flux with the flux mapping method. We presented and analyzed optical performance in terms of concentrated solar flux distribution and power distribution. We investigated concentration ratio, stagnation temperature, total power, and concentration accuracy with help of a modeling code based on the ray tracing method and thereby compared with other solar furnaces. We also discussed flux changes by shutter opening angles and by position adjustment of reflector facets. In the course of flux analysis, we provided a better understanding of reference flux measurement for calibration, reflectivity measurement with a portable reflectometer, shadowing area consideration for effective irradiation, as well as accuracy and repeatability of flux measurements. The results in the present study will help proper utilization of a solar furnace by facilitating comparison between flux measurements at different conditions and flux estimation during operation

Beta dose due to monazite sands of Kerala

International Nuclear Information System (INIS)

Massand, O.P.; Venkataraman, G.; Dhairyawan, M.P.

1977-01-01

The heavy black mineral sands of the sea coast of Kerala in India contain patches of monazite in concentrations varying between 0.5 to 5%. Monazite contains about 9.5% of thorium oxide (ThO 2 ) and 0.35% of uranium oxide (U 3 O 8 ). The high natural background radiation of this area had been a matter of concern and reports on the measured gamma radiation levels have appeared. The dose contribution due to beta rays emitted by the materials in the sand has been calculated using Loevinger's formula. The annual beta dose is of the order of 4200 mrad and 740 mrad at a height of 5 and 200 cm respectively from ground level. (author)

Particle size- and concentration-dependent separation of magnetic nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Witte, Kerstin, E-mail: witte@micromod.de [University of Rostock, Institute of Physics, Albert-Einstein-Str. 23, 18059 Rostock (Germany); Micromod Partikeltechnologie GmbH, Friedrich-Barnewitz-Str. 4, 18119 Rostock (Germany); Müller, Knut; Grüttner, Cordula; Westphal, Fritz [Micromod Partikeltechnologie GmbH, Friedrich-Barnewitz-Str. 4, 18119 Rostock (Germany); Johansson, Christer [Acreo Swedish ICT AB, 40014 Göteborg (Sweden)

2017-04-01

Small magnetic nanoparticles with a narrow size distribution are of great interest for several biomedical applications. When the size of the particles decreases, the magnetic moment of the particles decreases. This leads to a significant increase in the separation time by several orders of magnitude. Therefore, in the present study the separation processes of bionized nanoferrites (BNF) with different sizes and concentrations were investigated with the commercial Sepmag Q system. It was found that an increasing initial particle concentration leads to a reduction of the separation time for large nanoparticles due to the higher probability of building chains. Small nanoparticles showed exactly the opposite behavior with rising particle concentration up to 0.1 mg(Fe)/ml. For higher iron concentrations the separation time remains constant and the measured Z-average decreases in the supernatant at same time intervals. At half separation time a high yield with decreasing hydrodynamic diameter of particles can be obtained using higher initial particle concentrations. - Highlights: • Size dependent separation processes of multicore nanoparticles. • Concentration dependent separation processes of multicore nanoparticles. • Increasing separation time with rising concentrations for small particles. • Large particles show typical cooperative magnetophoresis behavior.

Feasibility of Topical Applications of Natural High-Concentration Capsaicinoid Solutions in Patients with Peripheral Neuropathic Pain: A Retrospective Analysis

Directory of Open Access Journals (Sweden)

Fanny Bauchy

2016-01-01

Full Text Available Background. Capsaicin, one of several capsaicinoid compounds, is a potent TRPV1 agonist. Topical application at high concentration (high concentration, >1% induces a reversible disappearance of epidermal free nerve endings and is used to treat peripheral neuropathic pain (PNP. While the benefit of low-concentration capsaicin remains controversial, the 8%-capsaicin patch (Qutenza®, 2010, Astellas, Netherlands has shown its effectiveness. This patch is, however, costly and natural high-concentration capsaicinoid solutions may represent a cheaper alternative to pure capsaicin. Methods. In this retrospective study, 149 patients were screened, 132 were included with a diagnosis of neuropathic pain, and eighty-four were retained in the final analyses (median age: 57.5 years [IQR25–75: 44.7–67.1], male/female: 30/54 with PNP who were treated with topical applications of natural high-concentration capsaicinoid solutions (total number of applications: 137. Indications were postsurgical PNP (85.7% and nonsurgical PNP (14.3% (posttraumatic, HIV-related, postherpetic, and radicular PNP. Objectives. To assess the feasibility of topical applications of natural high-concentration capsaicinoid solutions for the treatment of PNP. Results. The median treated area was 250 cm2 [IQR25–75: 144–531]. The median amount of capsaicinoids was 55.1 mg [IQR25–75: 28.7–76.5] per plaster and the median concentration was 172.3 μg/cm2 [IQR25–75: 127.6–255.2]. Most patients had local adverse effects on the day of treatment, such as mild to moderate burning pain and erythema. 13.6–19.4% of the patients experienced severe pain or erythema. Following treatment, 62.5% of patients reported a lower pain intensity or a smaller pain surface, and 35% reported a sustained pain relief lasting for at least 4 weeks. Conclusion. Analgesic topical treatment with natural high-concentration capsaicinoid is feasible and may represent a low cost alternative to alleviate

Inhalation exposures due to radon and thoron ((222)Rn and (220)Rn): Do they differ in high and normal background radiation areas in India?

Science.gov (United States)

Mishra, Rosaline; Sapra, B K; Prajith, R; Rout, R P; Jalaluddin, S; Mayya, Y S

2015-09-01

In India, High Background Radiation Areas (HBRAs) due to enhanced levels of naturally occurring radionuclides in soil (thorium and, to a lesser extent, uranium), are located along some parts of the coastal tracts viz. the coastal belt of Kerala, Tamilnadu and Odisha. It is conjectured that these deposits will result in higher emissions of radon isotopes ((222)Rn and (220)Rn) and their daughter products as compared to Normal Background Radiation Areas (NBRAs). While the annual external dose rates contributed by gamma radiations in these areas are about 5-10 times higher, the extent of increase in the inhalation dose rates attributable to (222)Rn and (220)Rn and their decay products is not well quantified. Towards this, systematic indoor surveys were conducted wherein simultaneous measurements of time integrated (222)Rn and (220)Rn gas and their decay product concentrations was carried out in around 800 houses in the HBRAs of Kerala and Odisha to estimate the inhalation doses. All gas measurements were carried out using pin-hole cup dosimeters while the progeny measurements were with samplers and systems based on the Direct radon/thoron Progeny sensors (DRPS/DTPS). To corroborate these passive measurements of decay products concentrations, active sampling was also carried out in a few houses. The results of the surveys provide a strong evidence to conclude that the inhalation doses due to (222)Rn and (220)Rn gas and their decay products in these HBRAs are in the same range as observed in the NBRAs in India. Copyright © 2015 Elsevier Ltd. All rights reserved.

Modelling and analysis of ozone concentration by artificial intelligent techniques for estimating air quality

Science.gov (United States)

Taylan, Osman

2017-02-01

High ozone concentration is an important cause of air pollution mainly due to its role in the greenhouse gas emission. Ozone is produced by photochemical processes which contain nitrogen oxides and volatile organic compounds in the lower atmospheric level. Therefore, monitoring and controlling the quality of air in the urban environment is very important due to the public health care. However, air quality prediction is a highly complex and non-linear process; usually several attributes have to be considered. Artificial intelligent (AI) techniques can be employed to monitor and evaluate the ozone concentration level. The aim of this study is to develop an Adaptive Neuro-Fuzzy inference approach (ANFIS) to determine the influence of peripheral factors on air quality and pollution which is an arising problem due to ozone level in Jeddah city. The concentration of ozone level was considered as a factor to predict the Air Quality (AQ) under the atmospheric conditions. Using Air Quality Standards of Saudi Arabia, ozone concentration level was modelled by employing certain factors such as; nitrogen oxide (NOx), atmospheric pressure, temperature, and relative humidity. Hence, an ANFIS model was developed to observe the ozone concentration level and the model performance was assessed by testing data obtained from the monitoring stations established by the General Authority of Meteorology and Environment Protection of Kingdom of Saudi Arabia. The outcomes of ANFIS model were re-assessed by fuzzy quality charts using quality specification and control limits based on US-EPA air quality standards. The results of present study show that the ANFIS model is a comprehensive approach for the estimation and assessment of ozone level and is a reliable approach to produce more genuine outcomes.

Coherent anti-Stokes Raman scattering for quantitative temperature and concentration measurements in a high-pressure gas turbine combustor rig

Science.gov (United States)

Thariyan, Mathew Paul

Dual-pump coherent anti-Stokes Raman scattering (DP-CARS) temperature and major species (CO2/N2) concentration measurements have been performed in an optically-accessible high-pressure gas turbine combustor facility (GTCF) and for partially-premixed and non-premixed flames in a laminar counter-flow burner. A window assembly incorporating pairs of thin and thick fused silica windows on three sides was designed, fabricated, and assembled in the GTCF for advanced laser diagnostic studies. An injection-seeded optical parametric oscillator (OPO) was used as a narrowband pump laser source in the dual-pump CARS system. Large prisms on computer-controlled translation stages were used to direct the CARS beams either into the main optics leg for measurements in the GTCF or to a reference optics leg for measurements of the nonresonant CARS spectrum and for aligning the CARS system. Combusting flows were stabilized with liquid fuel injection only for the central injector of a 9-element lean direct injection (LDI) device developed at NASA Glenn Research Center. The combustor was operated using Jet A fuel at inlet air temperatures up to 725 K and combustor pressures up to 1.03 MPa. Single-shot DP-CARS spectra were analyzed using the Sandia CARSFT code in the batch operation mode to yield instantaneous temperature and CO2/N2 concentration ratio values. Spatial maps of mean and standard deviations of temperature and CO2/N2 concentrations were obtained in the high-pressure LDI flames by translating the CARS probe volume in axial and vertical directions inside the combustor rig. The mean temperature fields demonstrate the effect of the combustor conditions on the overall flame length and the average flame structure. The temperature relative standard deviation values indicate thermal fluctuations due to the presence of recirculation zones and/or flame brush fluctuations. The correlation between the temperature and relative CO 2 concentration data has been studied at various combustor

Thermal denitration of high concentration nitrate salts waste water

International Nuclear Information System (INIS)

Hwang, D. S.; Oh, J. H.; Choi, Y. D.; Hwang, S. T.; Park, J. H.; Latge, C.

2003-01-01

This study investigated the thermodynamic and the thermal decomposition properties of high concentration nitrate salts waste water for the lagoon sludge treatment. The thermodynamic property was carried out by COACH and GEMINI II based on the composition of nitrate salts waste water. The thermal decomposition property was carried out by TG-DTA and XRD. Ammonium nitrate and sodium nitrate were decomposed at 250 .deg. C and 730 . deg. C, respectively. Sodium nitrate could be decomposed at 450 .deg. C in the case of adding alumina for converting unstable Na 2 O into stable Na 2 O.Al 2 O 3 . The flow sheet for nitrate salts waste water treatment was proposed based on the these properties data. These will be used by the basic data of the process simulation

Concentrate Supplement Modifies the Feeding Behavior of Simmental Cows Grazing in Two High Mountain Pastures.

Science.gov (United States)

Romanzin, Alberto; Corazzin, Mirco; Piasentier, Edi; Bovolenta, Stefano

2018-05-16

During grazing on Alpine pastures, the use of concentrates in dairy cows' diet leads to a reduction of the environmental sustainability of farms, and influences the selective pressure on some plant species. In order to minimize the use of concentrates, it is imperative to obtain data on the grazing behavior of cows. The aim of this study was to assess the effect of concentrate levels on the behavior of dairy cows during grazing. One hundred and ten lactating Italian Simmental cows, that sequentially grazed two pastures characterized by Poion alpinae (Poion) and Seslerion caeruleae (Seslerion) alliance, were considered. For each pasture, eight cows were selected and assigned to two groups: High and Low, supplemented with 4 kg/head/d, and 1 kg/head/d of concentrate respectively. Cows were equipped with a noseband pressure sensor and a pedometer (RumiWatch system, ITIN-HOCH GmbH) to assess grazing, ruminating, and walking behavior. In addition, the plant selection of the animals was assessed. On Poion, increased supplement intake caused a more intense selection of legumes, without affecting feeding and walking times. On Seslerion, grazing time was higher in Low than High. Grazing management in alpine region must take into account the great variability of pastures that largely differ from a floristic and nutritional point of view.

Serum concentrations of buprenorphine after oral and parenteral administration in male mice

DEFF Research Database (Denmark)

Kalliokoski, Otto; Jacobsen, Kirsten R; Hau, Jann

2011-01-01

Buprenorphine is the most commonly used drug for peri-operative pain relief in laboratory rodents. The systemic concentrations of buprenorphine were measured in mice following administration intravenously (IV), subcutaneously (SC), orally by gavage and by voluntary ingestion, to determine the post-administration...... serum concentration of buprenorphine. Voluntarily ingested buprenorphine resulted in long-lasting high serum concentrations, as did oral gavage administration (24h serum concentration: 110ngh/mL for both routes of administration). In contrast, buprenorphine administered parenterally remained...... in the circulation for a substantially shorter time (24h serum concentration for IV and SC were 40ngh/mL and 30ngh/mL, respectively). This marked difference was probably due to the higher dose used for oral administration, which is regarded necessary for sufficient analgesic effect, and to the slower absorption...

Sub-chronic inhalation of high concentrations of manganese sulfate induces lower airway pathology in rhesus monkeys

Directory of Open Access Journals (Sweden)

Wong Brian A

2005-10-01

Full Text Available Abstract Background Neurotoxicity and pulmonary dysfunction are well-recognized problems associated with prolonged human exposure to high concentrations of airborne manganese. Surprisingly, histological characterization of pulmonary responses induced by manganese remains incomplete. The primary objective of this study was to characterize histologic changes in the monkey respiratory tract following manganese inhalation. Methods Subchronic (6 hr/day, 5 days/week inhalation exposure of young male rhesus monkeys to manganese sulfate was performed. One cohort of monkeys (n = 4–6 animals/exposure concentration was exposed to air or manganese sulfate at 0.06, 0.3, or 1.5 mg Mn/m3 for 65 exposure days. Another eight monkeys were exposed to manganese sulfate at 1.5 mg Mn/m3 for 65 exposure days and held for 45 or 90 days before evaluation. A second cohort (n = 4 monkeys per time point was exposed to manganese sulfate at 1.5 mg Mn/m3 and evaluated after 15 or 33 exposure days. Evaluations included measurement of lung manganese concentrations and evaluation of respiratory histologic changes. Tissue manganese concentrations were compared for the exposure and control groups by tests for homogeneity of variance, analysis of variance, followed by Dunnett's multiple comparison. Histopathological findings were evaluated using a Pearson's Chi-Square test. Results Animals exposed to manganese sulfate at ≥0.3 mg Mn/m3 for 65 days had increased lung manganese concentrations. Exposure to manganese sulfate at 1.5 mg Mn/m3 for ≥15 exposure days resulted in increased lung manganese concentrations, mild subacute bronchiolitis, alveolar duct inflammation, and proliferation of bronchus-associated lymphoid tissue. Bronchiolitis and alveolar duct inflammatory changes were absent 45 days post-exposure, suggesting that these lesions are reversible upon cessation of subchronic high-dose manganese exposure. Conclusion High-dose subchronic manganese sulfate inhalation is

Concentration and size distribution of particles in abstracted groundwater.

Science.gov (United States)

van Beek, C G E M; de Zwart, A H; Balemans, M; Kooiman, J W; van Rosmalen, C; Timmer, H; Vandersluys, J; Stuyfzand, P J

2010-02-01

Particle number concentrations have been counted and particle size distributions calculated in groundwater derived by abstraction wells. Both concentration and size distribution are governed by the discharge rate: the higher this rate the higher the concentration and the higher the proportion of larger particles. However, the particle concentration in groundwater derived from abstraction wells, with high groundwater flow velocities, is much lower than in groundwater from monitor wells, with minimal flow velocities. This inconsistency points to exhaustion of the particle supply in the aquifer around wells due to groundwater abstraction for many years. The particle size distribution can be described with the help of a power law or Pareto distribution. Comparing the measured particle size distribution with the Pareto distribution shows that particles with a diameter >7 microm are under-represented. As the particle size distribution is dependent on the flow velocity, so is the value of the "Pareto" slope beta. (c) 2009 Elsevier Ltd. All rights reserved.

Corrosion mechanism of 13Cr stainless steel in completion fluid of high temperature and high concentration bromine salt

International Nuclear Information System (INIS)

Liu, Yan; Xu, Lining; Lu, Minxu; Meng, Yao; Zhu, Jinyang; Zhang, Lei

2014-01-01

Highlights: • The corrosion behavior of 13Cr steel exposed to bromine salt completion fluid containing high concentration bromine ions was investigated. • There are passive circles around pits on the 13Cr steel surface after 7 d of exposure. • Macroscopic galvanic corrosion formed between the passive halo and the pit. • The mechanism of pitting corrosion on 13Cr stainless steel exposed to heavy bromine brine was established. - Abstract: A series of corrosion tests of 13Cr stainless steel were conducted in a simulated completion fluid environment of high temperature and high concentration bromine salt. Corrosion behavior of specimens and the component of corrosion products were investigated by means of scanning electron microscope (SEM), confocal laser scanning microscopy (CLSM) and X-ray photoelectron spectroscopy (XPS). The results indicate that 13Cr steel suffers from severe local corrosion and there is always a passive halo around every pit. The formation mechanism of the passive halo is established. OH − ligand generates and adsorbs in a certain scale because of abundant OH − on the surface around the pits. Passive film forms around each pit, which leads to the occurrence of passivation in a certain region. Finally, the dissimilarities in properties and morphologies of regions, namely the pit and its corresponding passive halo, can result in different corrosion sensitivities and may promote the formation of macroscopic galvanic pairs

High pressure-temperature electrical conductivity of magnesiowustite as a function of iron oxide concentration

Science.gov (United States)

Li, Xiaoyuan; Jeanloz, Raymond

1990-01-01

The electrical conductivity of (Mg, Fe)O magnesiowustite containing 9 and 27.5 mol pct FeO has been measured at simultaneously high pressures (30-32 GPa) and temperatures using a diamond anvil cell heated with a continuous wave Nd:YAG laser and an external resistance heater. The conductivity depends strongly on the FeO concentration at both ambient and high pressures. At the pressures and temperatures of about 30 GPa and 2000 K, conditions expected in the lower mantle, the magnesiowustite containing 27.5 percent FeO is 3 orders of magnitude more conductive than that containing 9 percent FeO. The activation energy of magnesiowustite decreases with increasing iron concentration from 0.38 (+ or - 0.09) eV at 9 percent FeO to 0.29 (+ or - 0.05) eV at 27.5 percent FeO.

The effect of extremely high glucose concentrations on 21 routine chemistry and thyroid Abbott assays: interference study

OpenAIRE

?uhadar, Serap; K?seo?lu, Mehmet; ?inpolat, Yasemin; Bu?dayc?, G?ler; Usta, Murat; Semerci, Tuna

2016-01-01

Abstract Introduction: Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L. Materials and methods: Base...

Alcoholic fermentation by immobilized yeast at high sugar concentrations

Energy Technology Data Exchange (ETDEWEB)

Holcberg, I.B.; Margalith, P.

1981-01-01

Glucose fermentation by Saccharomyces cerevisiae immobilized by entrapment in agar, carrageenan, alginate and polyacrylamide gels, was compared to that of freely suspended cells at concentration of 10-50% (w.w.) sugar. The rate of ethanol production by the entrapped cells was 20-25% higher than that of the free cells. Concentrations of up to 14.5% w/w ethanol (30% glucose initial concentration) could be obtained. A number of hypotheses for the improved alcoholic fermentation are discussed.

Apportionment of the sources of high fine particulate matter concentration events in a developing aerotropolis in Taoyuan, Taiwan.

Science.gov (United States)

Chuang, Ming-Tung; Chen, Yu-Chieh; Lee, Chung-Te; Cheng, Chung-Hao; Tsai, Yu-Jen; Chang, Shih-Yu; Su, Zhen-Sen

2016-07-01

To investigate the characteristics and contributions of the sources of fine particulate matter with a size of up to 2.5 μm (PM2.5) during the period when pollution events could easily occur in Taoyuan aerotropolis, Taiwan, this study conducted sampling at three-day intervals from September 2014 to January 2015. Based on the mass concentration of PM2.5, the sampling days were classified into high PM2.5 concentration event days (PM2.5>35 μg m(-3)) and non-event days (PM2.5<35 μg m(-3)). In addition, the chemical species, including water-soluble inorganic ions, carbonaceous components, and metal elements, were analyzed. The sources of pollution and their contributions were estimated using the positive matrix factorization (PMF) model. Furthermore, the effect of the weather type on the measurement results was also explored based on wind field conditions. The mass fractions of Cl(-) and NO3(-) increased when a high PM2.5 concentration event occurred, and they were also higher under local emitted conditions than under long range transported conditions, indicating that secondary nitrate aerosols were the major increasing local species that caused high PM2.5 concentration events. Seven sources of pollution could be distinguished using the PMF model on the basis of the characteristics of the species. Industrial emissions, coal combustion/urban waste incineration, and local emissions from diesel/gasoline vehicles were the main sources that contributed to pollution on high PM2.5 concentration event days. In order to reduction of high PM2.5 concentration events, the control of diesel and gasoline vehicle emission is important and should be given priority. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of the acute adverse reaction of contrast medium with high and moderate iodine concentration in patients undergoing computed tomography

International Nuclear Information System (INIS)

Nagamoto, Masashi; Gomi, Tatsuya; Terada, Hitoshi; Terada, Shigehiko; Kohda, Eiichi

2006-01-01

The aim of this prospective study was to evaluate and compare acute adverse reactions between contrast medium containing moderate and high concentrations of iodine in patients undergoing computed tomography (CT). A total of 945 patients undergoing enhanced CT were randomly assigned to receive one of two doses of contrast medium. We then prospectively investigated the incidence of adverse reactions. Iopamidol was used as the contrast medium, with a high concentration of 370 mgI/ml and a moderate concentration of 300 mgI/ml. The frequency of adverse reactions, such as pain at the injection site and heat sensation, were determined. Acute adverse reactions were observed in 2.4% (11/458) of the moderate-concentration group compared to 3.11% (15/482) of the high-concentration group; there was no significant difference in incidence between the two groups. Most adverse reactions were mild, and there was no significant difference in severity. One patient in the high-concentration group was seen to have a moderate adverse reaction. No correlation existed between the incidence of adverse reactions and patient characteristics such as sex, age, weight, flow amount, and flow rate. The incidence of pain was not significantly different between the two groups. In contrast, the incidence of heat sensation was significantly higher in the high-concentration group. The incidence and severity of acute adverse reactions were not significantly different between the two groups, and there were no severe adverse reactions in either group. (author)

Postmortem computed tomographic (PMCT) findings of pericardial effusion due to acute aortic dissection

International Nuclear Information System (INIS)

Shiotani, Seiji; Watanabe, Ko; Kohno, Mototsugu; Ohashi, Noriyoshi; Nakayama, Hidetsugu; Yamazaki, Kentaro

2004-01-01

The purpose of this study was to describe the appearance of pericardial effusion in deceased acute aortic dissection patients using postmortem computed tomography (PMCT). PMCT examinations were performed within 2 hours of death in 30 patients with pericardial effusion due to aortic dissection who arrived at our hospital in a state of cardiopulmonary arrest. Pericardial effusion in 18 of 30 patients (60%) showed double concentric rings on PMCT with striking differences in density, a low-density outer ring along the pericardium and a high-density inner ring on the epicardial surface (hyperdense armored heart). Pericardial effusion in two patients (7%) showed a high-density fluid level (hypostasis). Pericardial effusion in the remaining 10 patients (33%) showed no such stratification. A ''hyperdense armored heart'' is the most frequently seen PMCT finding in deceased cases of pericardial effusion due to acute aortic dissection. (author)

Characteristics and treatment mechanism of mine water with high concentration of iron and manganese

Energy Technology Data Exchange (ETDEWEB)

Li, F.; Yang, J.; He, X.; Yang, J.; Tian, T. [Hebei University of Engineering, Handan (China)

2006-12-15

The characteristics and treatment of mine water with high concentration or iron and manganese were studied with mine water produced in Jiukuang and Siwan belonging to Hebi Coal Industry Group Co., Ltd. Analysis shows that the mine water is abundant in dissolved oxygen and has high TDS and high turbidity so the mine water does not need aeration. The effect of removal of iron and manganese by coagulation-sedimentation and the influence of filter material and influent water flow rate on effluent quality were investigated. It is shown that the removal rate of iron can reach 90% while removal of manganese can only reach about 20%. The concentration of iron and manganese in the effluent is lower than 0.1 mg/L with filter material of manganese sand which was immersed in KMnO{sub 4} solution at a filtration rate of 7 - 9 m/h. The results show that the layer of activated compound substance membrane formed on the surface of the manganese sand plays an important role in the removal of manganese. 7 refs., 2 figs., 3 tabs.

Spatially Resolved Temperature and Water Vapor Concentration Distributions in Supersonic Combustion Facilities by TDLAT

Science.gov (United States)

Busa, K. M.; McDaniel J. C.; Diskin, G. S.; DePiro, M. J.; Capriotti, D. P.; Gaffney, R. L.

2012-01-01

Detailed knowledge of the internal structure of high-enthalpy flows can provide valuable insight to the performance of scramjet combustors. Tunable Diode Laser Absorption Spectroscopy (TDLAS) is often employed to measure temperature and species concentration. However, TDLAS is a path-integrated line-of-sight (LOS) measurement, and thus does not produce spatially resolved distributions. Tunable Diode Laser Absorption Tomography (TDLAT) is a non-intrusive measurement technique for determining two-dimensional spatially resolved distributions of temperature and species concentration in high enthalpy flows. TDLAT combines TDLAS with tomographic image reconstruction. More than 2500 separate line-of-sight TDLAS measurements are analyzed in order to produce highly resolved temperature and species concentration distributions. Measurements have been collected at the University of Virginia's Supersonic Combustion Facility (UVaSCF) as well as at the NASA Langley Direct-Connect Supersonic Combustion Test Facility (DCSCTF). Due to the UVaSCF s unique electrical heating and ability for vitiate addition, measurements collected at the UVaSCF are presented as a calibration of the technique. Measurements collected at the DCSCTF required significant modifications to system hardware and software designs due to its larger measurement area and shorter test duration. Tomographic temperature and water vapor concentration distributions are presented from experimentation on the UVaSCF operating at a high temperature non-reacting case for water vitiation level of 12%. Initial LOS measurements from the NASA Langley DCSCTF operating at an equivalence ratio of 0.5 are also presented. Results show the capability of TDLAT to adapt to several experimental setups and test parameters.

Analysis of serotonin concentrations in human milk by high-performance liquid chromatography with fluorescence detection.

Science.gov (United States)

Chiba, Takeshi; Maeda, Tomoji; Tairabune, Tomohiko; Tomita, Takashi; Sanbe, Atsushi; Takeda, Rika; Kikuchi, Akihiko; Kudo, Kenzo

2017-03-25

Serotonin (5-hydroxytryptamine, 5-HT) plays an important role in milk volume homeostasis in the mammary gland during lactation; 5-HT in milk may also affect infant development. However, there are few reports on 5-HT concentrations in human breast milk. To address this issue, we developed a simple method based on high-performance liquid chromatography with fluorescence detection (HPLC-FD) for measuring 5-HT concentrations in human breast milk. Breast milk samples were provided by four healthy Japanese women. Calibration curves for 5-HT in each sample were prepared with the standard addition method between 5 and 1000 ng/ml, and all had correlation coefficients >0.999. The recovery of 5-HT was 96.1%-101.0%, with a coefficient of variation of 3.39%-8.62%. The range of 5-HT concentrations estimated from the calibration curves was 11.1-51.1 ng/ml. Thus, the HPLC-FD method described here can effectively extract 5-HT from human breast milk with high reproducibility. Copyright © 2017 Elsevier Inc. All rights reserved.

Full-field dye concentration measurement within saturated/unsaturated thin slabs of porous media

International Nuclear Information System (INIS)

Norton, D.L.; Glass, R.J.

1993-01-01

This paper presents a full-field dye concentration measurement technique that extends our experimental capabilities to the measurement of transient dye concentration fields within steady state flow fields under unsaturated or saturated conditions. Simple light absorption theory provides a basis for translating images into high resolution dye concentration fields. A series of dye pulse experiments that demonstrate the combined use of the full-field saturation and dye concentration techniques was conducted at four different degrees of saturation. Each of these experimental sequences was evaluated with respect to mass balance, the results being within 5% of the known dye mass input. An image windowing technique allowed us to see increased dispersion due to decreasing moisture content, tailing of concentration at the rear of the dye pulse and slight velocity changes of the dispersive front due to changes in moisture content. The exceptional resolution of dye concentration in space and time provided by this laboratory technique allows systematic experimentation for examining basic processes affecting solute transport within saturated/unsaturated porous media. Future challenges for this work will be to use these techniques to analyze more complex systems involving heterogeneities, scaling laws, and detailed investigations of the relationship between transverse and longitudinal dispersion in unsaturated media

Large-area, high-intensity PV arrays for systems using dish concentrating optics

Energy Technology Data Exchange (ETDEWEB)

Ward, J.S.; Duda, A.; Zweibel, K.; Coutts, T.J. [National Renewable Energy Lab., Golden, CO (United States)

1998-09-01

In this paper, the authors report on efforts to fabricate monolithic interconnected modules (MIMs) using III-V semiconductors with bandgaps appropriate for the terrestrial solar spectrum. The small size of the component cells comprising the MIM allows for operation at extremely high flux densities and relaxes the requirement for a small spot size to be generated by the optics. This makes possible a PV option for the large dish concentrator systems that have been developed by the solar thermal community for use with Stirling engines. Additionally, the highly effective back-surface reflector integrated into the MIM design is an effective tool for thermal management of the array. Development of this technology would radically alter the projections for PV manufacturing capacity because of the potential for extremely high power generation per unit area of semiconductor material.

Performance of high amylose starch-composited gelatin films influenced by gelatinization and concentration.

Science.gov (United States)

Wang, Wenhang; Wang, Kun; Xiao, Jingdong; Liu, Yaowei; Zhao, Yana; Liu, Anjun

2017-01-01

In order to study the impact of starch in film performance, high amylose corn starch was composited in gelatin films under different gelatinization conditions and, in high and low concentrations (10 and 50wt.%). It was found that hot water gelatinized starch (Gel-Shw) increased film mechanical strength and was dependent upon the starch concentration. The addition of an alkali component to the starch significantly enhanced the swelling of the starch granules and expedited the gelatinization process. Incorporation of starch, especially the alkalized starch (Sha), into the gelatin films decreased film solubility which improved its water resistance and water vapor permeability (WVP). Multiple techniques (DSC, TGA, FT-IR, and XRD) were used to characterize the process and results, including the crosslinking of the dissolved starch molecules and the particles formed from gelatinized starch during retrogradation process, which played an important role in improving the thermal stability of the composited gelatin films. Overall, the starch-gelatin composition provides a potential approach to improve gelatin film performance and benefit its applications in the food industry. Copyright © 2016 Elsevier B.V. All rights reserved.

Modelling horizontal and vertical concentration profiles of ozone and oxides of nitrogen within high-latitude urban areas

International Nuclear Information System (INIS)

Nicholson, J.P.; Weston, K.J.

2001-01-01

Urban ozone concentrations are determined by the balance between ozone destruction, chemical production and supply through advection and turbulent down-mixing from higher levels. At high latitudes, low levels of solar insolation and high horizontal advection speeds reduce the photochemical production and the spatial ozone concentration patterns are largely determined by the reaction of ozone with nitric oxide and dry deposition to the surface. A Lagrangian column model has been developed to simulate the mean (monthly and annual) three-dimensional structure in ozone and nitrogen oxides (NO x ) concentrations in the boundary-layer within and immediately around an urban area. The short-time-scale photochemical processes of ozone and NO x , as well as emissions and deposition to the ground, are simulated. The model has a horizontal resolution of 1x1km and high resolution in the vertical. It has been applied over a 100x100km domain containing the city of Edinburgh (at latitude 56 o N) to simulate the city-scale processes of pollutants. Results are presented, using averaged wind-flow frequencies and appropriate stability conditions, to show the extent of the depletion of ozone by city emissions. The long-term average spatial patterns in the surface ozone and NO x concentrations over the model domain are reproduced quantitatively. The model shows the average surface ozone concentrations in the urban area to be lower than the surrounding rural areas by typically 50% and that the areas experiencing a 20% ozone depletion are generally restricted to within the urban area. The depletion of the ozone concentration to less than 50% of the rural surface values extends only 20m vertically above the urban area. A series of monitoring sites for ozone, nitric oxide and nitrogen dioxide on a north-south transect through the city - from an urban, through a semi-rural, to a remote rural location - allows the comparison of modelled with observed data for the mean diurnal cycle of ozone

Transient pool boiling heat transfer due to increasing heat inputs in subcooled water at high pressures

International Nuclear Information System (INIS)

Fukuda, K.; Shiotsu, M.; Sakurai, A.

1995-01-01

Understanding of transient boiling phenomenon caused by increasing heat inputs in subcooled water at high pressures is necessary to predict correctly a severe accident due to a power burst in a water-cooled nuclear reactor. Transient maximum heat fluxes, q max , on a 1.2 mm diameter horizontal cylinder in a pool of saturated and subcooled water for exponential heat inputs, q o e t/T , with periods, τ, ranging from about 2 ms to 20 s at pressures from atmospheric up to 2063 kPa for water subcoolings from 0 to about 80 K were measured to obtain the extended data base to investigate the effect of high subcoolings on steady-state and transient maximum heat fluxes, q max . Two main mechanisms of q max exist depending on the exponential periods at low subcoolings. One is due to the time lag of the hydrodynamic instability which starts at steady-state maximum heat flux on fully developed nucleate boiling (FDNB), and the other is due to the heterogenous spontaneous nucleations (HSN) in flooded cavities which coexist with vapor bubbles growing up from active cavities. The shortest period corresponding to the maximum q max for long period range belonging to the former mechanism becomes longer and the q max mechanism for long period range shifts to that due the HSN on FDNB with the increase of subcooling and pressure. The longest period corresponding to the minimum q max for the short period range belonging to the latter mechanism becomes shorter with the increase in saturated pressure. On the contrary, the longest period becomes longer with the increase in subcooling at high pressures. Correlations for steady-state and transient maximum heat fluxes were presented for a wide range of pressure and subcooling

Transient pool boiling heat transfer due to increasing heat inputs in subcooled water at high pressures

Energy Technology Data Exchange (ETDEWEB)

Fukuda, K. [Kobe Univ. of Mercantile Marine (Japan); Shiotsu, M.; Sakurai, A. [Kyoto Univ. (Japan)

1995-09-01

Understanding of transient boiling phenomenon caused by increasing heat inputs in subcooled water at high pressures is necessary to predict correctly a severe accident due to a power burst in a water-cooled nuclear reactor. Transient maximum heat fluxes, q{sub max}, on a 1.2 mm diameter horizontal cylinder in a pool of saturated and subcooled water for exponential heat inputs, q{sub o}e{sup t/T}, with periods, {tau}, ranging from about 2 ms to 20 s at pressures from atmospheric up to 2063 kPa for water subcoolings from 0 to about 80 K were measured to obtain the extended data base to investigate the effect of high subcoolings on steady-state and transient maximum heat fluxes, q{sub max}. Two main mechanisms of q{sub max} exist depending on the exponential periods at low subcoolings. One is due to the time lag of the hydrodynamic instability which starts at steady-state maximum heat flux on fully developed nucleate boiling (FDNB), and the other is due to the heterogenous spontaneous nucleations (HSN) in flooded cavities which coexist with vapor bubbles growing up from active cavities. The shortest period corresponding to the maximum q{sub max} for long period range belonging to the former mechanism becomes longer and the q{sub max}mechanism for long period range shifts to that due the HSN on FDNB with the increase of subcooling and pressure. The longest period corresponding to the minimum q{sub max} for the short period range belonging to the latter mechanism becomes shorter with the increase in saturated pressure. On the contrary, the longest period becomes longer with the increase in subcooling at high pressures. Correlations for steady-state and transient maximum heat fluxes were presented for a wide range of pressure and subcooling.

Alcohol consumption is associated with high concentrations of urinary hydroxytyrosol.

Science.gov (United States)

Schröder, Helmut; de la Torre, Rafael; Estruch, Ramón; Corella, Dolores; Martínez-González, Miguel Angel; Salas-Salvadó, Jordi; Ros, Emilio; Arós, Fernando; Flores, Gemma; Civit, Ester; Farré, Magí; Fiol, Miguel; Vila, Joan; Fernandez-Crehuet, Joaquín; Ruiz-Gutiérrez, Valentina; Lapetra, Jose; Sáez, Guillermo; Covas, María-Isabel

2009-11-01

Previously, we reported the presence of hydroxytyrosol in red wine and higher human urinary recovery of total hydroxytyrosol than that expected after a single red wine intake. We hypothesized that the alcohol present in wine could promote endogenous hydroxytyrosol generation. The objective was to assess the relation between alcohol consumption and urinary hydroxytyrosol concentrations. This was a cross-sectional study with baseline data from a subsample of the PREvención con DIeta MEDiterránea (PREDIMED) trial, an intervention study directed at testing the efficacy of the Mediterranean diet on the primary prevention of cardiovascular disease. Participants included 1045 subjects, aged 55-80 y, who were at high cardiovascular risk. Alcohol consumption was estimated through a validated food-frequency questionnaire. Urinary hydroxytyrosol and ethyl glucuronide, a biomarker of alcohol consumption, were measured. Urinary ethyl glucuronide concentrations were directly related to alcohol and wine consumption (P logistic regression analyses showed a significant linear trend (P 20 g (2 drinks)/d and >10 g (1 drink)/d alcohol in men and women, respectively, were associated (P wine as a source of hydroxytyrosol and alcohol as an indirect promoter of endogenous hydroxytyrosol generation. This trial was registered at controlled-trials.com/isrctn/ as ISRCTN 35739639.

Modulating fluorescence quantum yield of highly concentrated fluorescein using differently shaped green synthesized gold nanoparticles

International Nuclear Information System (INIS)

John, Jisha; Thomas, Lincy; Kurian, Achamma; George, Sajan D.

2016-01-01

The interaction of dye molecules with differently shaped nanoparticles is of great interest owing to the potential applications in areas of bioimaging, sensing and photodynamic therapy (biology) as well as solar cells (photonics) applications. For such applications, noble metallic nanoparticles are commonly employed to either enhance or quench the luminescence of a nearby fluorophore. However, in most of the studies, the dye concentration is limited to avoid self-quenching. This paper reports the influence of differently shaped gold nanoparticles (spherical, bean and star), prepared via green synthesis, on the emission behavior as well as on the fluorescence quantum yield of fluorescein dye at concentrations for which self-quenching occurs. The emission behavior is probed via laser based steady state fluorescence whereas quantum yield is measured using a dual beam laser based thermal lens technique. The experimentally observed fluorescence quenching with a concomitant increase in thermal lens signal in the vicinity of nanoparticles are explained in terms of nonradiative energy transfer between the donor and the acceptor. Further, the influence of pH of the prepared gold nanofluid on the absorption, emission as well as quantum yield are also accounted. These studies elucidate that even at high concentrations of dye, the gold nanoparticle and its shape clearly influences the optical properties of nearby dye molecules and thus can be exploited for future applications. - Highlights: • Green synthesis of differently shaped gold nanoparticles. • Tailoring emission properties of fluorescein with respect to nanoparticle concentration and shape. • Tailoring the quantum yield of highly concentrated fluorescein with nanoparticles.

The uropathogenic species Staphylococcus saprophyticus tolerates a high concentration of D-serine.

Science.gov (United States)

Sakinç, Türkân; Michalski, Nadine; Kleine, Britta; Gatermann, Sören G

2009-10-01

Human urine contains a relatively high concentration of d-serine, which is toxic to several nonuropathogenic bacteria, but can be utilized or detoxified by uropathogenic Escherichia coli (UPEC). The sequenced genome of uropathogenic Staphylococcus saprophyticus contains a gene with homology to the d-serine deaminase gene (dsdA) of UPEC. We found the gene in several clinical isolates of S. saprophyticus; however, the gene was absent in Staphylococcus xylosus and Staphylococcus cohnii, phylogenetically close relatives of S. saprophyticus, and could also not be detected in isolates of Staphylococcus aureus, Staphylococcus epidermidis and 13 other staphylococcal species. In addition, the genomes of other sequenced staphylococci do not harbor homologues of this operon. Interestingly, S. saprophyticus could grow in media supplemented with relatively high concentrations of d-serine, whereas S. aureus, S. epidermidis and other staphylococcal species could not. The association of the dsdA gene with growth in media including d-serine was proved by introducing the gene into S. aureus Newman. Given the fact that UPEC and S. saprophyticus tolerate this compound, d-serine utilization and detoxification may be a general property of uropathogenic bacteria. © 2009 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Cylindrically symmetric Fresnel lens for high concentration photovoltaic

Science.gov (United States)

Hung, Yu-Ting; Su, Guo-Dung

2009-08-01

High concentration photovoltaic (HCPV) utilizes point-focus cost-effective plastic Fresnel lens. And a millimeter-sized Ill-V compound multi-junction solar cell is placed underneath focusing optics which can achieve cell efficiency potential of up to 40.7 %. The advantage of HCPV makes less solar cell area and higher efficiency; however, the acceptance angle of HCPV is about +/-1°, which is very small and the mechanical tracking of the sun is necessary. In order to reduce the power consumption and the angle tracking error of tracking systems, a light collector model with larger acceptance angle is designed with ZEMAX®. In this model, the original radially symmetric Fresnel lens of HCPV is replaced by cylindrically symmetric Fresnel lens and a parabolic reflective surface. Light is collected in two dimensions separately. And a couple of lenses and a light pipe are added before the solar cell chip in order to collect more light when sun light deviates from incident angle of 00. An acceptance angle of +/-10° is achieved with GCR 400.

Reduction of serum triacylglycerol-rich lipoprotein concentrations in cows with hepatic lipidosis.

Science.gov (United States)

Herdt, T H; Liesman, J S; Gerloff, B J; Emery, R S

1983-02-01

The hepatic and serum lipid concentrations in 49 dairy cows with displaced abomasum, 7 postpartum cows fasted for 6 days, and 14 healthy postpartum cows were studied. The cows with displaced abomasums were retrospectively allotted to 2 groups: those with greater than 15% liver fat (DAHF) and those with less than 15% liver fat (DALF). Liver total lipid concentrations were high in the DAHF group, exceeding these values in the fasted cows by 30% and in the healthy and DALF cows by 63% on the average. In contrast, the liver phospholipid concentrations were low in the DAHF group, intermediate in the fasted and DALF groups and high in the healthy group. On a group basis, an inverse relationship was observed between serum and liver lipid concentrations. The serum concentrations of both total and dextran-sulfate-precipitable (DSP) lipids were high in the fasted cows and were less in the DALF and healthy cows and in the DAHF cows (lowest). The between-group differences in serum total and serum DSP concentrations of triacylglycerol, cholesterol, and phospholipid followed the same quantitative pattern as the total lipids. However, the relative difference between groups was greater for each of the DSP lipid fractions. These results support the hypothesis that severe hepatic lipidosis in cattle occurs due to impaired hepatic lipoprotein synthesis and secretion.

Forecasting methodologies for Ganoderma spore concentration using combined statistical approaches and model evaluations

Science.gov (United States)

Sadyś, Magdalena; Skjøth, Carsten Ambelas; Kennedy, Roy

2016-04-01

High concentration levels of Ganoderma spp. spores were observed in Worcester, UK, during 2006-2010. These basidiospores are known to cause sensitization due to the allergen content and their small dimensions. This enables them to penetrate the lower part of the respiratory tract in humans. Establishment of a link between occurring symptoms of sensitization to Ganoderma spp. and other basidiospores is challenging due to lack of information regarding spore concentration in the air. Hence, aerobiological monitoring should be conducted, and if possible extended with the construction of forecast models. Daily mean concentration of allergenic Ganoderma spp. spores in the atmosphere of Worcester was measured using 7-day volumetric spore sampler through five consecutive years. The relationships between the presence of spores in the air and the weather parameters were examined. Forecast models were constructed for Ganoderma spp. spores using advanced statistical techniques, i.e. multivariate regression trees and artificial neural networks. Dew point temperature along with maximum temperature was the most important factor influencing the presence of spores in the air of Worcester. Based on these two major factors and several others of lesser importance, thresholds for certain levels of fungal spore concentration, i.e. low (0-49 s m-3), moderate (50-99 s m-3), high (100-149 s m-3) and very high (150 < n s m-3), could be designated. Despite some deviation in results obtained by artificial neural networks, authors have achieved a forecasting model, which was accurate (correlation between observed and predicted values varied from r s = 0.57 to r s = 0.68).

Radon concentration measurements in therapeutic spring water

International Nuclear Information System (INIS)

Deak, N.; Horvath, A.; Sajo B, L.; Marx, G.

1996-01-01

It is believed that people undergoing a curative cycle in a given spa, may receive a dose in the range of 400 mSv/year which is many times the average annual dose so that their risk of lung cancer may increase by 3% or more. To determine the risk due to the natural radioactivity, of the most frequented spas in Budapest (H), we selected four and some others located on the country side being of particular interest. Results of the radon concentration in spring water are presented, with the evidence that some spas have a high radon concentration. We conclude that patients receiving treatment may be exposed to an additional dose in the range of 29-76 mSv/year that at the bronchia could be between 445-1182 mSv/year. (authors). 6 refs., 2 figs., 2 tabs

Novel approach in k0-NAA for highly concentrated REE Samples.

Science.gov (United States)

Abdollahi Neisiani, M; Latifi, M; Chaouki, J; Chilian, C

2018-04-01

The present paper presents a new approach for k 0 -NAA for accurate quantification with short turnaround analysis times for rare earth elements (REEs) in high content mineral matrices. REE k 0 and Q 0 values, spectral interferences and nuclear interferences were experimentally evaluated and improved with Alfa Aesar Specpure Plasma Standard 1000mgkg -1 mono-rare earth solutions. The new iterative gamma-ray self-attenuation and neutron self-shielding methods were investigated with powder standards prepared from 100mg of 99.9% Alfa Aesar mono rare earth oxide diluted with silica oxide. The overall performance of the new k 0 -NAA method for REEs was validated using a certified reference material (CRM) from Canadian Certified Reference Materials Project (REE-2) with REE content ranging from 7.2mgkg -1 for Yb to 9610mgkg -1 for Ce. The REE concentration was determined with uncertainty below 7% (at 95% confidence level) and proved good consistency with the CRM certified concentrations. Copyright © 2017 Elsevier B.V. All rights reserved.

A highly concentrated diet increases biogas production and the agronomic value of young bull's manure.

Science.gov (United States)

Mendonça Costa, Mônica Sarolli Silva de; Lucas, Jorge de; Mendonça Costa, Luiz Antonio de; Orrico, Ana Carolina Amorim

2016-02-01

The increasing demand for animal protein has driven significant changes in cattle breeding systems, mainly in feedlots, with the use of young bulls fed on diets richer in concentrate (C) than in forage (F). These changes are likely to affect animal manure, demanding re-evaluation of the biogas production per kg of TS and VS added, as well as of its agronomic value as a biofertilizer, after anaerobic digestion. Here, we determined the biogas production and agronomic value (i.e., the macronutrient concentration in the final biofertilizer) of the manure of young bulls fed on diets with more (80% C+20% F; 'HighC' diet) or less (65% C+35% F; 'LowC' diet) concentrate, evaluating the effects of temperature (25, 35, and 40°C) and the use of an inoculum, during anaerobic digestion. A total of 24 benchtop reactors were used, operating in a semi-continuous system, with a 40-day hydraulic retention time (HRT). The manure from animals given the HighC diet had the greatest potential for biogas production, when digested with the use of an inoculum and at 35 or 40°C (0.6326 and 0.6207m(3)biogas/kg volatile solids, or VS, respectively). We observed the highest levels of the macronutrients N, P, and K in the biofertilizer from the manure of animals given HighC. Our results show that the manure of young bulls achieves its highest potential for biogas production and agronomic value when animals are fed diets richer in concentrate, and that biogas production increases if digestion is performed at higher temperatures, and with the use of an inoculum. Copyright © 2015 Elsevier Ltd. All rights reserved.

A sensitivity study on neutron flux variation due to 10B concentration in dose calculation for BNCT

International Nuclear Information System (INIS)

Jung, Sang Hoon

2006-02-01

The effects of inclusion of 10 B concentration on neutron flux and dose in dose calculation were studied. In order to provide the quantitative effects of inclusion of 10 B concentrations on depressions of neutron and photon flux and dose, the fluxes and doses with voxel head phantoms for various 10 B concentrations homogeneously distributed were calculated by using MCNPX simulations. A lithium target system and beam shaping assembly, which have been developed at the Hanyang University, were used as epithermal neutron beam. The calculation results show that the neutron flux at the center of the head phantom decreases by approximately 5.4% per 10 ppm of 10 B concentration in comparison with the neutron flux in the case of boron-free. It was also observed that the tissue dose at the center of the head phantom is depressed by approximately 4.7% per 10 ppm of the 10 B concentration and the tumor dose by approximately 5.3% per 10 ppm. According to depth of tumors, it was observed that the depressions of the doses in the tumors are ranged in 3.7 ∼ 9.2%. The dose calculations in the case of boron-free show that it is overestimated in comparison with the dose calculations in the cases of the inclusion of 10 B concentrations for the normal tissue and the tumors. Therefore, in dose calculation for BNCT, the depressions of neutron flux and dose should be considered. The results in this study are available to setting up the depression ratios which can be used for converting neutron and gamma fluxes and doses in phantom with boron free into the fluxes and doses in phantom with inclusion of 10 B concentrations in treatment. It is expected that the depression ratios is practicable to dose evaluation for BNCT

Concentration and distribution of dioxins and related compounds in various human organs

Energy Technology Data Exchange (ETDEWEB)

Iida, T.; Hirakawa, H.; Hori, T.; Tobiishi, K.; Matsueda, T. [Fukuoka Inst. of Health and Environmental Sciences, Dazaifu, Fukuoka (Japan); Todaka, T. [Japan Food Hygiene Association, Tokyo (Japan); Watanabe, S. [Tokyo Univ. of Agriculture, Tokyo (Japan); Yamada, T. [Keio Univ. School of Medicine, Tokyo (Japan)

2004-09-15

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and non-ortho coplanar polychlorinated biphenyls (Non-Co-PCBs) and mono-ortho coplanar polychlorinated biphenyls (Mono-Co-PCBs) accumulate in the human body due to their highly lipophilic properties. In recent years, there has been some concern about the potential health effects of dioxins and related chemicals for the general population of humans. Although there exists an enormous amount of data on this subject, most of it is from breast milk and blood, due to ease of collection; information concerning concentrations and distribution in various human organs hardly exists. Therefore, new data concerning various human tissues is required to evaluate the pathophysiological significance of dioxins and related compounds in humans. The aim of this study was to investigate the concentration levels and distribution of dioxins and related compounds in various human organ tissues. We previously reported on the concentration levels in the human liver and adipose tissues from 28 donors. In this paper, we determined the concentrations of dioxin-like isomers in 8 organs, including blood, lungs, liver, bile, spleen, pancreas, kidney and mesentery fat from 20 donors.

Removal of high concentration p-nitrophenol in aqueous solution by zero valent iron with ultrasonic irradiation (US–ZVI)

International Nuclear Information System (INIS)

Lai, Bo; Chen, Zhaoyu; Zhou, Yuexi; Yang, Ping; Wang, Juling; Chen, Zhiqiang

2013-01-01

Highlights: ► High concentration PNP can be reduced into the nontoxic p-aminophenol by US–ZVI. ► High removal efficiency of PNP is resulted from the synergistic reaction of ZVI and US. ► The reaction pathway of PNP in the US–ZVI system is proposed. ► Processing parameters of the US–ZVI system were optimized seriously. -- Abstract: In this study, the US–ZVI system was used to produce the strong reductants including ·H and nascent Fe 2+ ions to eliminate the toxicity of the high concentration p-nitrophenol (PNP) wastewater. The effect of the reactor structure, initial pH, ZVI dosage, ultrasonic power and initial PNP concentration on the removal efficiency of PNP from water was investigated intensively. The results show that a higher removal rate can be obtained by using a conical structure reactor, and the lower initial pH can aid the acceleration of PNP removal rate by using US–ZVI system. Furthermore, the removal efficiencies of PNP increased obviously with the increase of initial ZVI concentration from 0 to 15 g L −1 . Also, the treatment capacity of ZVI was enhanced remarkably by the ultrasonic irradiation, and the US–ZVI system can maintain high treatment efficiency for the high concentration PNP wastewater (500–10,000 mg L −1 ). Meanwhile, the high removal efficiency of PNP was mainly resulted from the synergistic reaction of ZVI and US. At last, the main degradation product (i.e., p-aminophenol) was detected by gas chromatography–mass spectrum (GC–MS). Thus, the reaction pathway of PNP in the US–ZVI system is proposed as a reducing process by the ·H and nascent Fe 2+ ions

Removal of high concentration p-nitrophenol in aqueous solution by zero valent iron with ultrasonic irradiation (US–ZVI)

Energy Technology Data Exchange (ETDEWEB)

Lai, Bo, E-mail: laibo1981@163.com [School of Architecture and Environment, Sichuan University, Chengdu 610065 (China); Chen, Zhaoyu [School of Architecture and Environment, Sichuan University, Chengdu 610065 (China); Zhou, Yuexi [Research Center of Water Pollution Control Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Yang, Ping [School of Architecture and Environment, Sichuan University, Chengdu 610065 (China); Wang, Juling [Research Center of Water Pollution Control Technology, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Chen, Zhiqiang [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090 (China)

2013-04-15

Highlights: ► High concentration PNP can be reduced into the nontoxic p-aminophenol by US–ZVI. ► High removal efficiency of PNP is resulted from the synergistic reaction of ZVI and US. ► The reaction pathway of PNP in the US–ZVI system is proposed. ► Processing parameters of the US–ZVI system were optimized seriously. -- Abstract: In this study, the US–ZVI system was used to produce the strong reductants including ·H and nascent Fe{sup 2+} ions to eliminate the toxicity of the high concentration p-nitrophenol (PNP) wastewater. The effect of the reactor structure, initial pH, ZVI dosage, ultrasonic power and initial PNP concentration on the removal efficiency of PNP from water was investigated intensively. The results show that a higher removal rate can be obtained by using a conical structure reactor, and the lower initial pH can aid the acceleration of PNP removal rate by using US–ZVI system. Furthermore, the removal efficiencies of PNP increased obviously with the increase of initial ZVI concentration from 0 to 15 g L{sup −1}. Also, the treatment capacity of ZVI was enhanced remarkably by the ultrasonic irradiation, and the US–ZVI system can maintain high treatment efficiency for the high concentration PNP wastewater (500–10,000 mg L{sup −1}). Meanwhile, the high removal efficiency of PNP was mainly resulted from the synergistic reaction of ZVI and US. At last, the main degradation product (i.e., p-aminophenol) was detected by gas chromatography–mass spectrum (GC–MS). Thus, the reaction pathway of PNP in the US–ZVI system is proposed as a reducing process by the ·H and nascent Fe{sup 2+} ions.

Application of crown-ethers to caesium and strontium removal from Marcoule reprocessing concentrate

International Nuclear Information System (INIS)

Dozol, J.F.; Garcia, J.C.i; Sastre, A.M.

1991-01-01

The liquid wastes arising from reprocessing plants are treated by evaporation, the distillate is discharged into environment and the concentrate containing all the active and inactive salts must be stored in geological formation, after embedding, due to the activity of long life radionuclides (actinides, Cs, Sr). The object of the work is to remove actinides and cesium/strontium from high sodium content acidic concentrated in order to sharply decrease the volume of wastes to be stored in geological formation. (author)

Application of crown-ethers to cesium and strontium removal from Marcoule reprocessing concentrate

International Nuclear Information System (INIS)

Dozol, J.F.; Casas I Garcia, J.

1990-01-01

The liquid wastes arising from reprocessing plants are treated by evaporation, the distillate is discharged into environment and the concentrate containing all the active and inactive salts must be stored in geological formation, after embedding, due to the activity of long life radionuclides (actinides, Cs, Sr). The objective of this work, is after removal actinides, to remove cesium/strontium from high sodium content acidic concentrates in order to sharply decrease the volume of wastes to be stored in geological formation

Arsenic concentrations in Chinese coals

International Nuclear Information System (INIS)

Wang Mingshi; Zheng Baoshan; Wang Binbin; Li Shehong; Wu Daishe; Hu Jun

2006-01-01

The arsenic concentrations in 297 coal samples were collected from the main coal-mines of 26 provinces in China were determined by molybdenum blue coloration method. These samples were collected from coals that vary widely in coal rank and coal-forming periods from the five main coal-bearing regions in China. Arsenic content in Chinese coals range between 0.24 to 71 mg/kg. The mean of the concentration of Arsenic is 6.4 ± 0.5 mg/kg and the geometric mean is 4.0 ± 8.5 mg/kg. The level of arsenic in China is higher in northeastern and southern provinces, but lower in northwestern provinces. The relationship between arsenic content and coal-forming period, coal rank is studied. It was observed that the arsenic contents decreases with coal rank in the order: Tertiary > Early Jurassic > Late Triassic > Late Jurassic > Middle Jurassic > Late Permian > Early Carboniferous > Middle Carboniferous > Late Carboniferous > Early Permian; It was also noted that the arsenic contents decrease in the order: Subbituminous > Anthracite > Bituminous. However, compared with the geological characteristics of coal forming region, coal rank and coal-forming period have little effect on the concentration of arsenic in Chinese coal. The average arsenic concentration of Chinese coal is lower than that of the whole world. The health problems in China derived from in coal (arsenism) are due largely to poor local life-style practices in cooking and home heating with coal rather than to high arsenic contents in the coal

Concentrate Supplement Modifies the Feeding Behavior of Simmental Cows Grazing in Two High Mountain Pastures

Directory of Open Access Journals (Sweden)

Alberto Romanzin

2018-05-01

Full Text Available During grazing on Alpine pastures, the use of concentrates in dairy cows’ diet leads to a reduction of the environmental sustainability of farms, and influences the selective pressure on some plant species. In order to minimize the use of concentrates, it is imperative to obtain data on the grazing behavior of cows. The aim of this study was to assess the effect of concentrate levels on the behavior of dairy cows during grazing. One hundred and ten lactating Italian Simmental cows, that sequentially grazed two pastures characterized by Poion alpinae (Poion and Seslerion caeruleae (Seslerion alliance, were considered. For each pasture, eight cows were selected and assigned to two groups: High and Low, supplemented with 4 kg/head/d, and 1 kg/head/d of concentrate respectively. Cows were equipped with a noseband pressure sensor and a pedometer (RumiWatch system, ITIN-HOCH GmbH to assess grazing, ruminating, and walking behavior. In addition, the plant selection of the animals was assessed. On Poion, increased supplement intake caused a more intense selection of legumes, without affecting feeding and walking times. On Seslerion, grazing time was higher in Low than High. Grazing management in alpine region must take into account the great variability of pastures that largely differ from a floristic and nutritional point of view.

A high-protein diet increases postprandial but not fasting plasma total homocysteine concentrations: A dietary controlled, crossover trial in healthy volunteers

NARCIS (Netherlands)

Verhoef, P.; Vliet, T. van; Olthof, M.R.; Katan, M.B.

2005-01-01

Background: A high plasma concentration of total homocysteine (tHcy) is associated with increased risk of cardiovascular disease. A high protein intake and hence a high intake of methionine-the sole dietary precursor of homocysteine-may raise plasma tHcy concentrations. Objectives: We studied

A high-protein diet increases postprandial but not fasting plasma total homocysteine concentrations : A dietary controlled, crossover trial in healthy volunteers

NARCIS (Netherlands)

Verhoef, Petra; Van Vliet, Trinette; Olthof, Margreet R.; Katan, Martijn B.

2005-01-01

Background: A high plasma concentration of total homocysteine (tHcy) is associated with increased risk of cardiovascular disease. A high protein intake and hence a high intake of methionine-the sole dietary precursor of homocysteine-may raise plasma tHcy concentrations. Objectives: We studied

The role of silicon interstitials in the deactivation and reactivation of high concentration boron profiles

Energy Technology Data Exchange (ETDEWEB)

Aboy, Maria [Campus Miguel Delibes, University of Valladolid, 47011 Valladolid (Spain)]. E-mail: marabo@tel.uva.es; Pelaz, Lourdes [Campus Miguel Delibes, University of Valladolid, 47011 Valladolid (Spain); Marques, Luis A. [Campus Miguel Delibes, University of Valladolid, 47011 Valladolid (Spain); Lopez, Pedro [Campus Miguel Delibes, University of Valladolid, 47011 Valladolid (Spain); Barbolla, Juan [Campus Miguel Delibes, University of Valladolid, 47011 Valladolid (Spain); Venezia, V.C. [Philips Research Leuven, Leuven (Belgium); Duffy, R. [Philips Research Leuven, Leuven (Belgium); Griffin, Peter B. [Stanford University, Stanford, CA (United States)

2004-12-15

Boron cluster formation and dissolution in high concentration B profiles and the role of Si interstitials in these processes are analyzed by kinetic non-lattice Monte Carlo atomistic simulations. For this purpose, we use theoretical structures as simplifications of boron implants into preamorphized Si, followed by low-temperature solid phase epitaxial (SPE) regrowth or laser thermal annealing process. We observe that in the presence of high B concentrations (above 10{sup 20} cm{sup -3}), significant deactivation occurs during high temperature anneal, even in the presence of only equilibrium Si interstitials. The presence of additional Si interstitials from an end of range (EOR) damage region accelerates the deactivation process and makes B deactivation slightly higher. We show that B deactivation and reactivation processes can be clearly correlated to the evolution of Si interstitial defects at the EOR. The minimum level of activation occurs when the Si interstitial defects at EOR dissolve or form very stable defects.

III-V/Active-Silicon Integration for Low-Cost High-Performance Concentrator Photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Ringel, Steven [The Ohio State Univ., Columbus, OH (United States); Carlin, John A [The Ohio State Univ., Columbus, OH (United States); Grassman, Tyler [The Ohio State Univ., Columbus, OH (United States)

2018-04-17

This FPACE project was motivated by the need to establish the foundational pathway to achieve concentrator solar cell efficiencies greater than 50%. At such an efficiency, DOE modeling projected that a III-V CPV module cost of $0.50/W or better could be achieved. Therefore, the goal of this project was to investigate, develop and advance a III-V/Si mulitjunction (MJ) CPV technology that can simultaneously address the primary cost barrier for III-V MJ solar cells while enabling nearly ideal MJ bandgap profiles that can yield efficiencies in excess of 50% under concentrated sunlight. The proposed methodology was based on use of our recently developed GaAsP metamorphic graded buffer as a pathway to integrate unique GaAsP and Ga-rich GaInP middle and top junctions having bandgaps that are adjustable between 1.45 – 1.65 eV and 1.9 – 2.1 eV, respectively, with an underlying, 1.1 eV active Si subcell/substrate. With this design, the Si can be an active component sub-cell due to the semi-transparent nature of the GaAsP buffer with respect to Si as well as a low-cost alternative substrate that is amenable to scaling with existing Si foundry infrastructure, providing a reduction in materials cost and a low cost path to manufacturing at scale. By backside bonding of a SiGe, a path to exceed 50% efficiency is possible. Throughout the course of this effort, an expansive range of new understanding was achieved that has stimulated worldwide efforts in III-V/Si PV R&D that spanned materials development, metamorphic device optimization, and complete III-V/Si monolithic integration. Highlights include the demonstration of the first ideal GaP/Si interfaces grown by industry-standard MOCVD processes, the first high performance metamorphic tunnel junctions designed for III-V/Si integration, record performance of specific metamorphic sub-cell designs, the first fully integrated GaInP/GaAsP/Si double (1.7 eV/1.1 eV) and triple (1.95 eV/1.5 eV/1.1 eV) junction solar cells, the first

Adaptation to high salt concentrations in halotolerant/ halophilic fungi: a molecular perspective

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Ana ePlemenitas

2014-05-01

Full Text Available Molecular studies of salt tolerance of eukaryotic microorganisms have until recently been limited to the baker’s yeast Saccharomyces cerevisiae and a few other moderately halotolerant yeast. Discovery of the extremely halotolerant and adaptable fungus Hortaea werneckii and the obligate halophile Wallemia ichthyophaga introduced two new model organisms into studies on the mechanisms of salt tolerance in eukaryotes. H. werneckii is unique in its adaptability to fluctuations in salt concentrations, as it can grow without NaCl as well as in the presence of up to 5 M NaCl. On the other hand, W. ichthyophaga requires at least 1.5 M NaCl for growth, but also grows in up to 5 M NaCl. Our studies have revealed the novel and intricate molecular mechanisms used by these fungi to combat high salt concentrations, which differ in many aspects between the extremely halotolerant H. werneckii and the halophilic W. ichthyophaga. Specifically, the high osmolarity glycerol signalling pathway that is important for sensing and responding to increased salt concentrations is here compared between H. werneckii and W. ichthyophaga. In both of these fungi, the key signalling components are conserved, but there are structural and regulation differences between these pathways in H. werneckii and W. ichthyophaga. We also address differences that have been revealed from analysis of their newly sequenced genomes. The most striking characteristics associated with H. werneckii are the large genetic redundancy, the expansion of genes encoding metal cation transporters, and a relatively recent whole genome duplication. In contrast, the genome of W. ichthyophaga is very compact, as only 4,884 protein-coding genes are predicted, which cover almost three quarters of the sequence. Importantly, there has been a significant increase in their hydrophobins, cell-wall proteins that have multiple cellular functions.

Assessment of external and internal doses due to farming in high background radiation areas in old tin mining localities in Jos-plateau, Nigeria

International Nuclear Information System (INIS)

Jibiri, N.N.; Farai, I.P.; Alausa, S.K.

2009-01-01

Farming on soils situated in high background radiation areas can result to enhanced radiation exposure scenarios and pathways to humans. To assess the likely levels of exposures, farm soil samples were collected from different farmlands in three old tin mining localities (Bitsichi, Bukuru and Ropp) in Jos Plateau Nigeria, known for high radiations. The soil samples were analyzed for the activity concentrations of 226 Ra, 232 Th and 40 K, using gamma-ray spectroscopy. The outdoor annual effective dose rates were calculated using the activity concentrations of the radionuclides and were found to vary from 0.07 mSv to 2.02 mSv across the three localities. Considering dust generation from soil tillage and inadvertent ingestion of soil particles, the likely internal radiation hazards were estimated using conservative dust and soil loading factors. The total average annual effective dose rates due to 226 Ra and 232 Th that could result from dust inhalation and ingestion of soil particles were 16.9 μSv, 8.1 μSv and 8.8 μSv, respectively for Bitsichi, Bukuru and Ropp. Though these values are about 5% the outdoor exposures to the farmers in those farms and greater than 1 μSv y-1, from the point of view of radiation protection and risk, they are significant. It suffices to say, therefore, that the results of this study will create the possibility of the importance to evaluate the health risk among the farming population and workplace environments which often is not covered by regulations concerning health protection. (author)

Effects of niacin supplementation and dietary concentrate proportion on body temperature, ruminal pH and milk performance of primiparous dairy cows.

Science.gov (United States)

Lohölter, Malte; Meyer, Ulrich; Rauls, Caroline; Rehage, Jürgen; Dänicke, Sven

2013-06-01

The objective of this study was to investigate the effects of niacin and dietary concentrate proportion on body temperature, ruminal pH and milk production of dairy cows. In a 2 × 2 factorial design, 20 primiparous Holstein cows (179 ± 12 days in milk) were assigned to four dietary treatments aimed to receive either 0 or 24 g niacin and 30% (low) or 60% (high) concentrate with the rest being a partial mixed ration (PMR) composed of 60% corn and 40% grass silage (on dry matter basis). Ambient temperature and relative humidity were determined and combined by the calculation of temperature humidity index. Respiration rates, rectal, skin and subcutaneous temperatures were measured. Milk production and composition were determined. Ruminal pH and temperature were recorded at a frequency of 5 min using wireless devices for continuous intra-ruminal measurement (boluses). pH values were corrected for pH sensor drift. The climatic conditions varied considerably but temporarily indicated mild heat stress. Niacin did not affect skin, rectal and subcutaneous temperatures but tended to increase respiration rates. High concentrate reduced skin temperatures at rump, thigh and neck by 0.1-0.3°C. Due to the technical disturbances, not all bolus data could be subjected to statistical evaluation. However, both niacin and high concentrate influenced mean ruminal pH. High concentrate increased the time spent with a pH below 5.6 and ruminal temperatures (0.2-0.3°C). Niacin and high concentrate enhanced milk, protein and lactose yield but reduced milk fat and protein content. Milk fat yield was slightly reduced by high concentrate but increased due to niacin supplementation. In conclusion, niacin did not affect body temperature but stimulated milk performance. High concentrate partially influenced body temperatures and had beneficial effects on milk production.

A high-protein diet increases postprandial but not fasting plasma total homocysteine concentrations: a dietary controlled, crossover trial in healthy volunteers

NARCIS (Netherlands)

Verhoef, P.; Vliet, van T.; Olthof, M.R.; Katan, M.B.

2005-01-01

Background: A high plasma concentration of total homocysteine (tHcy) is associated with increased risk of cardiovascular disease. A high protein intake and hence a high intake of methionine¿the sole dietary precursor of homocysteine¿may raise plasma tHcy concentrations. Objectives: We studied

Carbon assimilation in Eucalyptus urophylla grown under high atmospheric CO2 concentrations: A proteomics perspective.

Science.gov (United States)

Santos, Bruna Marques Dos; Balbuena, Tiago Santana

2017-01-06

Photosynthetic organisms may be drastically affected by the future climate projections of a considerable increase in CO 2 concentrations. Growth under a high concentration of CO 2 could stimulate carbon assimilation-especially in C3-type plants. We used a proteomics approach to test the hypothesis of an increase in the abundance of the enzymes involved in carbon assimilation in Eucalyptus urophylla plants grown under conditions of high atmospheric CO 2 . Our strategy allowed the profiling of all Calvin-Benson cycle enzymes and associated protein species. Among the 816 isolated proteins, those involved in carbon fixation were found to be the most abundant ones. An increase in the abundance of six key enzymes out of the eleven core enzymes involved in carbon fixation was detected in plants grown at a high CO 2 concentration. Proteome changes were corroborated by the detection of a decrease in the stomatal aperture and in the vascular bundle area in Eucalyptus urophylla plantlets grown in an environment of high atmospheric CO 2 . Our proteomics approach indicates a positive metabolic response regarding carbon fixation in a CO 2 -enriched atmosphere. The slight but significant increase in the abundance of the Calvin enzymes suggests that stomatal closure did not prevent an increase in the carbon assimilation rates. The sample enrichment strategy and data analysis used here enabled the identification of all enzymes and most protein isoforms involved in the Calvin-Benson-Bessham cycle in Eucalyptus urophylla. Upon growth in CO 2 -enriched chambers, Eucalyptus urophylla plantlets responded by reducing the vascular bundle area and stomatal aperture size and by increasing the abundance of six of the eleven core enzymes involved in carbon fixation. Our proteome approach provides an estimate on how a commercially important C3-type plant would respond to an increase in CO 2 concentrations. Additionally, confirmation at the protein level of the predicted genes involved in

Ambient aerosol concentrations of sugars and sugar-alcohols at four different sites in Norway

Directory of Open Access Journals (Sweden)

K. E. Yttri

2007-08-01

Full Text Available Sugars and sugar-alcohols are demonstrated to be important constituents of the ambient aerosol water-soluble organic carbon fraction, and to be tracers for primary biological aerosol particles (PBAP. In the present study, levels of four sugars (fructose, glucose, sucrose, trehalose and three sugar-alcohols (arabitol, inositol, mannitol in ambient aerosols have been quantified using a novel HPLC/HRMS-TOF (High Performance Liquid Chromatography in combination with High Resolution Mass Spectrometry – Time of Flight method to assess the contribution of PBAP to PM>sub>10 and PM_2.5. Samples were collected at four sites in Norway at different times of the year in order to reflect the various contributing sources and the spatial and seasonal variation of the selected compounds.

Sugars and sugar-alcohols were present at all sites investigated, underlining the ubiquity of these highly polar organic compounds. The highest concentrations were reported for sucrose, reaching a maximum concentration of 320 ng m⁻³ in PM₁₀ and 55 ng m⁻³ in PM_2.5. The mean concentration of sucrose was up to 10 times higher than fructose, glucose and the dimeric sugar trehalose. The mean concentrations of the sugar-alcohols were typically lower, or equal, to that of the monomeric sugars and trehalose. Peak concentrations of arabitol and mannitol did not exceed 30 ng m⁻³ in PM₁₀, and for PM_2.5 all concentrations were below 6 ng m⁻³.

Sugars and sugar-alcohols were associated primarily with coarse aerosols except during wintertime at the suburban site in Elverum, where a shift towards sub micron aerosols was observed. It is proposed that this shift was due to the intensive use of wood burning for residential heating at this site during winter, confirmed by high concurrent concentrations of levoglucosan. Elevated concentrations of sugars in PM₂