A Facile Method for Separating and Enriching Nano and Submicron Particles from Titanium Dioxide Found in Food and Pharmaceutical Products

Science.gov (United States)

Yang, Yu; Capco, David G.; Westerhoff, Paul

2016-01-01

Recent studies indicate the presence of nano-scale titanium dioxide (TiO2) as an additive in human foodstuffs, but a practical protocol to isolate and separate nano-fractions from soluble foodstuffs as a source of material remains elusive. As such, we developed a method for separating the nano and submicron fractions found in commercial-grade TiO2 (E171) and E171 extracted from soluble foodstuffs and pharmaceutical products (e.g., chewing gum, pain reliever, and allergy medicine). Primary particle analysis of commercial-grade E171 indicated that 54% of particles were nano-sized (i.e., < 100 nm). Isolation and primary particle analysis of five consumer goods intended to be ingested revealed differences in the percent of nano-sized particles from 32%‒58%. Separation and enrichment of nano- and submicron-sized particles from commercial-grade E171 and E171 isolated from foodstuffs and pharmaceuticals was accomplished using rate-zonal centrifugation. Commercial-grade E171 was separated into nano- and submicron-enriched fractions consisting of a nano:submicron fraction of approximately 0.45:1 and 3.2:1, respectively. E171 extracted from gum had nano:submicron fractions of 1.4:1 and 0.19:1 for nano- and submicron-enriched, respectively. We show a difference in particle adhesion to the cell surface, which was found to be dependent on particle size and epithelial orientation. Finally, we provide evidence that E171 particles are not immediately cytotoxic to the Caco-2 human intestinal epithelium model. These data suggest that this separation method is appropriate for studies interested in isolating the nano-sized particle fraction taken directly from consumer products, in order to study separately the effects of nano and submicron particles. PMID:27798677

Practical Considerations for Detection and Characterization of Sub-Micron Particles in Protein Solutions by Nanoparticle Tracking Analysis.

Science.gov (United States)

Gruia, Flaviu; Parupudi, Arun; Polozova, Alla

2015-01-01

Nanoparticle Tracking Analysis (NTA) is an emerging analytical technique developed for detection, sizing, and counting of sub-micron particles in liquid media. Its feasibility for use in biopharmaceutical development was evaluated with particle standards and recombinant protein solutions. Measurements of aqueous suspensions of NIST-traceable polystyrene particle standards showed accurate particle concentration detection between 2 × 10(7) and 5 × 10(9) particles/mL. Sizing was accurate for particle standards up to 200 nm. Smaller than nominal value sizes were detected by NTA for the 300-900 nm particles. Measurements of protein solutions showed that NTA performance is solution-specific. Reduced sensitivity, especially in opalescent solutions, was observed. Measurements in such solutions may require sample dilution; however, common sample manipulations, such as dilution and filtration, may result in particle formation. Dilution and filtration case studies are presented to further illustrate such behavior. To benchmark general performance, NTA was compared against asymmetric flow field flow fractionation coupled with multi-angle light scattering (aF4-MALS) and dynamic light scattering, which are other techniques for sub-micron particles. Data shows that all three methods have limitations and may not work equally well under certain conditions. Nevertheless, the ability of NTA to directly detect and count sub-micron particles is a feature not matched by aF4-MALS or dynamic light scattering. Thorough characterization of particulate matter present in protein therapeutics is limited by the lack of analytical methods for particles in the sub-micron size range. Emerging techniques are being developed to bridge this analytical gap. In this study, Nanoparticle Tracking Analysis is evaluated as a potential tool for biologics development. Our results indicate that method performance is molecule-specific and may not work as well under all solution conditions, especially when

The effect of particle size and concentration on the flow properties of a homogeneous slurry

International Nuclear Information System (INIS)

Abbas, M.A.; Crowe, C.T.

1986-01-01

This paper presents the results of the effects of particle size and concentration on the velocity distribution in the fully developed flow of a homogeneous slurry. The slurry consisted of chloroform and silica gel with matched index of refraction to enable Laser-Doppler anemometry (LDA) measurements through the mixture. Slurries with two particle sizes and solids concentration up to 30% by volume were studied. Measurements were made over a Reynolds number range of 1,200 to 30,000

A Facile Method for Separating and Enriching Nano and Submicron Particles from Titanium Dioxide Found in Food and Pharmaceutical Products.

Science.gov (United States)

Faust, James J; Doudrick, Kyle; Yang, Yu; Capco, David G; Westerhoff, Paul

2016-01-01

Recent studies indicate the presence of nano-scale titanium dioxide (TiO2) as an additive in human foodstuffs, but a practical protocol to isolate and separate nano-fractions from soluble foodstuffs as a source of material remains elusive. As such, we developed a method for separating the nano and submicron fractions found in commercial-grade TiO2 (E171) and E171 extracted from soluble foodstuffs and pharmaceutical products (e.g., chewing gum, pain reliever, and allergy medicine). Primary particle analysis of commercial-grade E171 indicated that 54% of particles were nano-sized (i.e., E171 and E171 isolated from foodstuffs and pharmaceuticals was accomplished using rate-zonal centrifugation. Commercial-grade E171 was separated into nano- and submicron-enriched fractions consisting of a nano:submicron fraction of approximately 0.45:1 and 3.2:1, respectively. E171 extracted from gum had nano:submicron fractions of 1.4:1 and 0.19:1 for nano- and submicron-enriched, respectively. We show a difference in particle adhesion to the cell surface, which was found to be dependent on particle size and epithelial orientation. Finally, we provide evidence that E171 particles are not immediately cytotoxic to the Caco-2 human intestinal epithelium model. These data suggest that this separation method is appropriate for studies interested in isolating the nano-sized particle fraction taken directly from consumer products, in order to study separately the effects of nano and submicron particles.

The effects of surface-charged submicron polystyrene particles on the structure and performance of PSF forward osmosis membrane

Science.gov (United States)

Zuo, Hao-Ran; Fu, Jia-Bei; Cao, Gui-Ping; Hu, Nian; Lu, Hui; Liu, Hui-Qing; Chen, Peng-Peng; Yu, Jie

2018-04-01

Monodisperse surface-charged submicron polystyrene particles were designed, synthesized, and blended into polysulfone (PSF) support layer to prepare forward osmosis (FO) membrane with high performance. The membrane incorporated with particles were characterized with respect to morphology, porosity, and internal osmotic pressure (IOP). Results showed that the polymer particles not only increased the hydrophilicity and porosity of support layer, but also generated considerable IOP, which helped markedly decreasing the structure parameter from 1550 to 670 μm. The measured mass transfer parameters further confirmed the beneficial effects of the surface-charged submicron polymer particles on the performance of FO membrane. For instance, the water permeability coefficient (5.37 L m-2 h-1 bar-1) and water flux (49.7 L m-2 h-1) of the FO membrane incorporated with 5 wt% particles were almost twice as much as that of FO membrane without incorporation. This study suggests that monodisperse surface-charged submicron polymer particles are potential modifiers for improving the performance of FO membranes.

The role of jet and film drops in controlling the mixing state of submicron sea spray aerosol particles

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiaofei; Deane, Grant B.; Moore, Kathryn A.; Ryder, Olivia S.; Stokes, M. Dale; Beall, Charlotte M.; Collins, Douglas B.; Santander, Mitchell V.; Burrows, Susannah M.; Sultana, Camille M.; Prather, Kimberly A.

2017-06-19

Covering 71% of the Earth’s surface, oceans represent a significant global source of atmospheric aerosols. The size and composition of sea spray aerosols (SSA) affect their ability to serve as cloud seeds and thus understanding the factors controlling their composition is critical to predicting their impact on clouds and climate. SSA particles have been shown to be an external mixture of particles with different compositions. Film and jet drop production mechanisms ultimately determine the individual particle compositions which are comprised of an array of salt/organic mixtures ranging from pure sea salt to nearly pure organic particles. It is often assumed that the majority of submicron SSA are formed by film drops produced from bursting hydrophobic organic-rich bubble film caps at the sea surface, and in contrast, jet drops are postulated to produce larger supermicron particles from underlying seawater comprised largely of salts and water soluble organic species. However, here we show that jet drops produced by bursting sub-100 m bubbles account for up to 40 % of all submicron particles. They have distinct chemical compositions, organic volume fractions and ice nucleating activities from submicron film drops. Thus a substantial fraction of submicron particles will not necessarily be controlled by the composition of the sea surface microlayer as has been assumed in many studies. This finding has significant ramifications for the size-resolved mixing states of SSA particles which must be taken into consideration when accessing SSA impacts on clouds.

Preparation and characterization of SiO2-coated submicron-sized L10 Fe-Pt particles

Directory of Open Access Journals (Sweden)

Yoshiaki Hayashi

2018-05-01

Full Text Available The development of magnets with higher performance is attracting increasing interest. The optimization of their microstructure is essential to enhance their properties, and a microstructure comprising magnetically isolated hard magnetic grains of a single-domain size has been proposed as an ideal structure for enhancing the coercivity of magnets. To obtain magnets with an ideal structure, we consider the fabrication of magnets by an approach based on core/shell nanoparticles with a hard magnetic core and a non-magnetic shell. In this study, to obtain particles for our proposed approach, we attempted to fabricate L10 Fe-Pt/SiO2-core/shell particles with submicron-sized cores less than the critical single-domain size. The fabrication of such core/shell particles was confirmed from morphology observations and XRD analysis of the particles. Although the formation of more desirable core/shell particles with submicron-sized single-crystal cores in the single-domain size range was not achieved, the fabricated core/shell particles showed a high coercivity of 25 kOe.

Neurotoxicity of low-dose repeatedly intranasal instillation of nano- and submicron-sized ferric oxide particles in mice

Energy Technology Data Exchange (ETDEWEB)

Wang Bing; Feng Weiyue, E-mail: fengwy@mail.ihep.ac.cn; Zhu Motao; Wang Yun; Wang Meng [Chinese Academy of Sciences, Laboratory for Bio-Environmental Effects of Nanomaterials and Nanosafety and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics (China); Gu Yiqun [Maternity Hospital of Haidian District (China); Ouyang Hong; Wang Huajian; Li Ming; Zhao Yuliang, E-mail: zhaoyuliang@mail.ihep.ac.cn; Chai Zhifang [Chinese Academy of Sciences, Laboratory for Bio-Environmental Effects of Nanomaterials and Nanosafety and Key Laboratory of Nuclear Analytical Techniques, Institute of High Energy Physics (China); Wang Haifang [Peking University, College of Chemistry and Molecular Engineering (China)

2009-01-15

Olfactory tract has been demonstrated to be an important portal for inhaled solid nanoparticle transportation into the central nervous system (CNS). We have previously demonstrated that intranasally instilled Fe{sub 2}O{sub 3} nanoparticles could transport into the CNS via olfactory pathway. In this study, we investigated the neurotoxicity and size effect of repeatedly low-dose (130 {mu}g) intranasal exposure of nano- and submicron-sized Fe{sub 2}O{sub 3} particles (21 nm and 280 nm) to mice. The biomarkers of oxidative stress, activity of nitric oxide synthases and release of monoamine neurotransmitter in the brain were studied. Our results showed that significant oxidative stress was induced by the two sizes of Fe{sub 2}O{sub 3} particles. The activities of GSH-Px, Cu,Zn-SOD, and cNOS significantly elevated and the total GSH and GSH/GSSG ratio significantly decreased in the olfactory bulb and hippocampus after the nano- and submicron-sized Fe{sub 2}O{sub 3} particle treatment (p < 0.05). The nano-sized Fe{sub 2}O{sub 3} generally induced greater alteration and more significant dose-effect response than the submicron-sized particle did. Some slight perturbation of monoamine neurotransmitters were found in the hippocampus after exposure to the two sizes of Fe{sub 2}O{sub 3} particle. The TEM image showed that some ultrastructural alterations in nerve cells, including neurodendron degeneration, membranous structure disruption and lysosome increase in the olfactory bulb, slight dilation in the rough endoplasmic reticulum and lysosome increase in the hippocampus were induced by the nano-sized Fe{sub 2}O{sub 3} treatment. In contrast, in the submicron-sized Fe{sub 2}O{sub 3} treated mice, slightly swollen mitochondria and some vacuoles were observed in the olfactory bulb and hippocampus, respectively. These results indicate that intranasal exposure of Fe{sub 2}O{sub 3} nanoparticles could induce more severe oxidative stress and nerve cell damage in the brain than the

Submicron polycaprolactone particles as a carrier for imaging contrast agent for in vitro applications.

Science.gov (United States)

Iqbal, Muhammad; Robin, Sophie; Humbert, Philippe; Viennet, Céline; Agusti, Geraldine; Fessi, Hatem; Elaissari, Abdelhamid

2015-12-01

Fluorescent materials have recently attracted considerable attention due to their unique properties and high performance as imaging agent in biomedical fields. Different imaging agents have been encapsulated in order to restrict its delivery to a specific area. In this study, a fluorescent contrast agent was encapsulated for in vitro application by polycaprolactone (PCL) polymer. The encapsulation was performed using modified double emulsion solvent evaporation technique with sonication. Fluorescent nanoparticles (20 nm) were incorporated in the inner aqueous phase of double emulsion. A number of samples were fabricated using different concentrations of fluorescent contrast agent. The contrast agent-containing submicron particle was characterized by a zetasizer for average particle size, SEM and TEM for morphology observations and fluorescence spectrophotometer for encapsulation efficiency. Moreover, contrast agent distribution in the PCL matrix was determined by confocal microscopy. The incorporation of contrast agent in different concentrations did not affect the physicochemical properties of PCL particles and the average size of encapsulated particles was found to be in the submicron range. Copyright © 2015 Elsevier B.V. All rights reserved.

SCOPING STUDIES TO DEVELOP A METHOD TO DETERMINE PARTICLE SIZE IN SIMULANT SLUDGE SLURRIES BY SIEVING

International Nuclear Information System (INIS)

DAMON, CLICK

2005-01-01

A physical separation method (i.e. sieving) was investigated to determine particle size distribution in non-radioactive sludge slurry simulants with the goal of implementation into the SRNL (Savannah River National Laboratory) shielded cells for use with radioactive sludge slurries. The investigation included obtaining the necessary experimental equipment, developing accessory equipment for use with the sieve shaker (to be able to sieve simulant slurries with aqueous solutions), sieving three different simulant slurries through a number of sieves and determining the particle size distribution gravimetrically, and developing a sufficient cleaning protocol of the sieves for re-use. The experimental protocol involved successive sieving of a NIST standard (to check the particle size retention of the sieves) and three non-radioactive slurry simulants (Batch 3 Tank 40 Test 3, Tank 40 Drum 3 and CETL Sludge Batch 2, which had been previously characterized by Microtrac analysis) through smaller and smaller sieves (150 microns x 5 microns) via use of the wet sieving system or by hand. For each of the three slurries, duplicate experiments were carried out using filtered supernate and DI water (to check the accuracy of the method versus Microtrac data) to sieve the slurry. Particle size determinations using the wet sieving system with DI water agree well with Microtrac data on a volume basis and in some cases the sieving data may be more accurate particularly if the material sieved had large particles. A correction factor had to be applied to data obtained from experiments done with supernate due to the dissolved solids which dried upon the sieves in the drying stage of the experiments. Upon subtraction of the correction factors, the experimental results were very similar to those obtained with DI water. It should be noted that approximately 250 mL of each of three simulant slurries was necessary to have enough filtered supernate available to carry out the experiments. The

The capture of submicron particles by collector plates - Wind-tunnel investigations

International Nuclear Information System (INIS)

Gauthier, Daniel

1971-01-01

The deposition of submicron particles on collector plates parallel to the flow was studied experimentally in a wind-tunnel. The validity of a theoretical model based on brownian diffusion was investigated and its Inadequacies tested. The aerosol sample consisted of uranine particles (mean geometrical radius: about 0. 1 μm). The average flow speeds varied from 1 to 10 m/s and the length of the collector plates between 1 and 10 cm. Results showed that capture was mainly due to diffusion and was in good agreement with the theoretical model; however a noticeable deposit of particles on the front part of the collector edge was observed. Sedimentation was insignificant in almost all the cases. (author) [fr

Study of the Parametric Performance of Solid Particle Erosion Wear under the Slurry Pot Test Rig

Directory of Open Access Journals (Sweden)

S.R. More

2017-12-01

Full Text Available Stainless Steel (SS 304 is commonly used material for slurry handling applications like pipelines, valves, pumps and other equipment's. Slurry erosion wear is a common problem in many engineering applications like process industry, thermal and hydraulic power plants and slurry handling equipments. In this paper, experimental investigation of the influence of solid particle size, impact velocity, impact angle and solid concentration parameters in slurry erosion wear behavior of SS 304 using slurry pot test rig. In this study the design of experiments was considered using Taguchi technique. A comparison has been made for the experimental and Taguchi technique results. The erosion wear morphology was studied using micro-graph obtained by scanning electron microscope (SEM analysis. At shallow impact angle 30°, the material removal pattern was observed in the form of micro displacing, scratching and ploughing with plastic deformation of the material. At 60° impact angle, mixed type of micro indentations and pitting action is observed. At normal impact angle 90°, the material removal pattern was observed in form of indentation and rounded lips. It is found that particle velocity was the most influence factor than impact angle, size and solid concentration. From this investigation, it can be concluded that the slurry erosion wear is minimized by controlling the slurry flow velocity which improves the service life of the slurry handling equipments. From the comparison of experimental and Taguchi experimental design results it is found that the percentage deviation was very small with a higher correlation coefficient (r2 0.987 which is agreeable.

Size-selective separation of submicron particles in suspensions with ultrasonic atomization.

Science.gov (United States)

Nii, Susumu; Oka, Naoyoshi

2014-11-01

Aqueous suspensions containing silica or polystyrene latex were ultrasonically atomized for separating particles of a specific size. With the help of a fog involving fine liquid droplets with a narrow size distribution, submicron particles in a limited size-range were successfully separated from suspensions. Performance of the separation was characterized by analyzing the size and the concentration of collected particles with a high resolution method. Irradiation of 2.4MHz ultrasound to sample suspensions allowed the separation of particles of specific size from 90 to 320nm without regarding the type of material. Addition of a small amount of nonionic surfactant, PONPE20 to SiO2 suspensions enhanced the collection of finer particles, and achieved a remarkable increase in the number of collected particles. Degassing of the sample suspension resulted in eliminating the separation performance. Dissolved air in suspensions plays an important role in this separation. Copyright © 2014 Elsevier B.V. All rights reserved.

Slurry explosives containing the combination of nitrogen-base salt and hard solid particles as sensitizer

Energy Technology Data Exchange (ETDEWEB)

Lyerly, W.M.

1971-11-02

In recent years, blasting agents, particularly those of the type known as water gels or slurry explosives have gained considerable commercial acceptance. Generally, the slurry explosives are comprised of an inorganic oxidizing salt, predominantly ammonium nitrate, a thickening agent for the liquid, water, and fuel. The density, velocity of detonation, and ability to sustain detonation are increased so that the compositions propagate in small diameter boreholes. A water-bearing slurry explosive is described containing inorganic oxidizing salt, fuel, water and thickener together with nitrogen- base salt and solid particles having a hardness of at least 4 on the Mohs scale and that have an acoustic impedance at least 2 times that of the matrix of the slurry explosive. (15 claims)

Study of lead phytoavailability for atmospheric industrial micronic and sub-micronic particles in relation with lead speciation

Energy Technology Data Exchange (ETDEWEB)

Uzu, G. [EcoLab UMR 5245 CNRS-INPT-UPS, ENSAT BP 32607 Auzeville Tolosane, 31326 Castanet Tolosan (France)], E-mail: gaelle.uzu@ensat.fr; Sobanska, S. [LASIR UMR 8516, Universite des Sciences et Technologies de Lille, Batiment C5, 59655 Villeneuve d' Ascq Cedex (France)], E-mail: Sophie.Sobanska@univ-lille1.fr; Aliouane, Y. [EcoLab UMR 5245 CNRS-INPT-UPS, ENSAT BP 32607 Auzeville Tolosane, 31326 Castanet Tolosan (France); Pradere, P. [Chemical Metal Treatment Company, STCM, 30-32 chemin de Fondeyre, 31200 Toulouse (France)], E-mail: p.pradere@stc-metaux.com; Dumat, C. [EcoLab UMR 5245 CNRS-INPT-UPS, ENSAT BP 32607 Auzeville Tolosane, 31326 Castanet Tolosan (France)], E-mail: camille.dumat@ensat.fr

2009-04-15

Particles from channelled emissions of a battery recycling facility were size-segregated and investigated to correlate their speciation and morphology with their transfer towards lettuce. Microculture experiments carried out with various calcareous soils spiked with micronic and sub-micronic particles (1650 {+-} 20 mg Pb kg{sup -1}) highlighted a greater transfer in soils mixed with the finest particles. According to XRD and Raman spectroscopy results, the two fractions presented differences in the amount of minor lead compounds like carbonates, but their speciation was quite similar, in decreasing order of abundance: PbS, PbSO{sub 4}, PbSO{sub 4}.PbO, {alpha}-PbO and Pb{sup 0}. Morphology investigations revealed that PM{sub 2.5} (i.e. Particulate Matter 2.5 composed of particles suspended in air with aerodynamic diameters of 2.5 {mu}m or less) contained many Pb nanoballs and nanocrystals which could influence lead availability. The soil-plant transfer of lead was mainly influenced by size and was very well estimated by 0.01 M CaCl{sub 2} extraction. - The soil-lettuce lead transfer from atmospheric industrial sub-micronic and micronic particles depends on particle size.

Study of lead phytoavailability for atmospheric industrial micronic and sub-micronic particles in relation with lead speciation

International Nuclear Information System (INIS)

Uzu, G.; Sobanska, S.; Aliouane, Y.; Pradere, P.; Dumat, C.

2009-01-01

Particles from channelled emissions of a battery recycling facility were size-segregated and investigated to correlate their speciation and morphology with their transfer towards lettuce. Microculture experiments carried out with various calcareous soils spiked with micronic and sub-micronic particles (1650 ± 20 mg Pb kg -1 ) highlighted a greater transfer in soils mixed with the finest particles. According to XRD and Raman spectroscopy results, the two fractions presented differences in the amount of minor lead compounds like carbonates, but their speciation was quite similar, in decreasing order of abundance: PbS, PbSO 4 , PbSO 4 .PbO, α-PbO and Pb 0 . Morphology investigations revealed that PM 2.5 (i.e. Particulate Matter 2.5 composed of particles suspended in air with aerodynamic diameters of 2.5 μm or less) contained many Pb nanoballs and nanocrystals which could influence lead availability. The soil-plant transfer of lead was mainly influenced by size and was very well estimated by 0.01 M CaCl 2 extraction. - The soil-lettuce lead transfer from atmospheric industrial sub-micronic and micronic particles depends on particle size

Submicron particle mass concentrations and sources in the Amazonian wet season (AMAZE-08)

Energy Technology Data Exchange (ETDEWEB)

Chen, Q.; Farmer, D. K.; Rizzo, L. V.; Pauliqueivis, T.; Kuwata, Mikinori; Karl, Thomas G.; Guenther, Alex B.; Allan, James D.; Coe, H.; Andreae, M. O.; Poeschl, U.; Jiminez, J. L.; Artaxo, Paulo; Martin, Scot T.

2015-01-01

Real-time mass spectra of non-refractory component of submicron aerosol particles were recorded in a tropical rainforest in the central Amazon basin during the wet season of 2008, as a part of the Amazonian Aerosol Characterization Experiment (AMAZE-08). Organic components accounted on average for more than 80% of the non-refractory submicron particle mass concentrations during the period of measurements. Ammonium was present in sufficient quantities to halfway neutralize sulfate. In this acidic, isoprene-dominated, low-NOx environment the high-resolution mass spectra as well as mass closures with ion chromatography measurements did not provide evidence for significant contributions of organosulfate species, at least at concentrations above uncertainty levels. Positive-matrix factorization of the time series of particle mass spectra identified four statistical factors to account for the variance of the signal intensities of the organic constituents: a factor HOA having a hydrocarbon-like signature and identified as regional emissions of primary organic material, a factor OOA-1 associated with fresh production of secondary organic material by a mechanism of BVOC oxidation followed by gas-to-particle conversion, a factor OOA-2 consistent with reactive uptake of isoprene oxidation products, especially epoxydiols by acidic particles, and a factor OOA-3 associated with long range transport and atmospheric aging. The OOA-1, -2, and -3 factors had progressively more oxidized signatures. Diameter-resolved mass spectral markers also suggested enhanced reactive uptake of isoprene oxidation products to the accumulation mode for the OOA-2 factor, and such size partitioning can be indicative of in-cloud process. The campaign-average factor loadings were in a ratio of 1.1:1.0 for the OOA-1 compared to the OOA-2 pathway, suggesting the comparable importance of gas-phase compared to particle-phase (including cloud waters) production pathways of secondary organic material during

Number Size Distributions and Seasonality of Submicron Particles in Europe 2008–2009

Czech Academy of Sciences Publication Activity Database

Asmi, A.; Wiedensohler, A.; Laj, P.; Fjaeraa, A.-M.; Sellegri, K.; Birmili, W.; Weingartner, E.; Baltensperger, U.; Ždímal, Vladimír; Zíková, Naděžda; Putaud, J.-P.; Marioni, A.; Tunved, P.; Hansson, H.-C.; Fiebig, M.; Kivekäs, N.; Lihavainen, H.; Asmi, E.; Ulevicius, V.; Aalto, P.P.; Swietlicki, E.; Kristensson, E.; Mihalopoulos, N.; Kalivitis, N.; Kalapov, I.; Kiss, G.; de Leeuw, G.; Henzig, B.; Harrison, R. M.; Beddows, D.; O´Dowd, C.; Jennings, S.G.; Flentje, H.; Weinhold, K.; Meinhardt, F.; Ries, L.; Kulmala, M.

2011-01-01

Roč. 11, - (2011), s. 5505-5538 ISSN 1680-7316 EU Projects: European Commission(XE) RII3-CT-2006-026140; European Commission(XE) 36833; European Commission(IT) Ev-K2-CNR Grant - others:AFCE(FI) 1118615 Program:FP6 Institutional research plan: CEZ:AV0Z40720504 Keywords : aerosol particle number * aerosol concentrations * european submicron Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 5.520, year: 2011

Quantitative cellular uptake of double fluorescent core-shelled model submicronic particles

Energy Technology Data Exchange (ETDEWEB)

Leclerc, Lara, E-mail: leclerc@emse.fr [Ecole Nationale Superieure des Mines, CIS-EMSE, LINA (France); Boudard, Delphine [LINA (France); Pourchez, Jeremie; Forest, Valerie [Ecole Nationale Superieure des Mines, CIS-EMSE, LINA (France); Marmuse, Laurence; Louis, Cedric [NANO-H S.A.S (France); Bin, Valerie [LINA (France); Palle, Sabine [Universite Jean Monnet, Centre de Microscopie Confocale Multiphotonique (France); Grosseau, Philippe; Bernache-Assollant, Didier [Ecole Nationale Superieure des Mines, CIS-EMSE, LINA (France); Cottier, Michele [LINA (France)

2012-11-15

The relationship between particles' physicochemical parameters, their uptake by cells and their degree of biological toxicity represent a crucial issue, especially for the development of new technologies such as fabrication of micro- and nanoparticles in the promising field of drug delivery systems. This work was aimed at developing a proof-of-concept for a novel model of double fluorescence submicronic particles that could be spotted inside phagolysosomes. Fluorescein isothiocyanate (FITC) particles were synthesized and then conjugated with a fluorescent pHrodo Trade-Mark-Sign probe, red fluorescence of which increases in acidic conditions such as within lysosomes. After validation in acellular conditions by spectral analysis with confocal microscopy and dynamic light scattering, quantification of phagocytosis was conducted on a macrophage cell line in vitro. The biological impact of pHrodo functionalization (cytotoxicity, inflammatory response, and oxidative stress) was also investigated. Results validate the proof-of-concept of double fluorescent particles (FITC + pHrodo), allowing detection of entirely engulfed pHrodo particles (green and red labeling). Moreover incorporation of pHrodo had no major effects on cytotoxicity compared to particles without pHrodo, making them a powerful tool for micro- and nanotechnologies.

Preparation of submicron-sized spherical particles of gold using laser-induced melting in liquids and low-toxic stabilizing reagent

International Nuclear Information System (INIS)

Tsuji, T.; Higashi, Y.; Tsuji, M.; Ishikawa, Y.; Koshizaki, N.

2015-01-01

Highlights: • Submicron-sized spherical particles of gold were prepared using laser irradiation for the source gold nanoparticles stabilized by NaCl. • The source gold nanoparticles agglomeration was controlled both by the NaCl concentration of and by laser irradiation. • The formation process and the laser-fluence dependence of the particle size of gold nanoparticles in NaCl solutions differs from those in citrate solutions. • We revealed that properties of ligands are significantly important to prepare submicron-sized spherical particles and to control their size. - Abstract: Laser-induced melting in liquids (LIML) was applied to prepare spherical submicron-sized particles of gold (AuSMPs) from gold nanoparticles (AuNPs) stabilized using NaCl. Because undesirable byproducts, which might be generated when organic reagents such as citrate are used as the stabilizing reagent, are not generated from NaCl by laser irradiation, AuSMPs fabricated from AuNPs stabilized by NaCl will be low toxic. The AuSMPs were obtained by laser irradiation of the source AuNPs in NaCl solutions stabilized by NaCl at the proper concentration. Similar to the preparation of AuSMPs from AuNPs stabilized by citrate, the agglomeration of the source AuNPs, which is necessary to obtain AuSMPs, was controlled both by the NaCl concentration and by laser irradiation. However, the formation process and the laser-fluence dependence of the particle size of AuSMPs differed for various NaCl solutions and citrate solutions

Medical ice slurry production device

Science.gov (United States)

Kasza, Kenneth E [Palos Park, IL; Oras, John [Des Plaines, IL; Son, HyunJin [Naperville, IL

2008-06-24

The present invention relates to an apparatus for producing sterile ice slurries for medical cooling applications. The apparatus is capable of producing highly loaded slurries suitable for delivery to targeted internal organs of a patient, such as the brain, heart, lungs, stomach, kidneys, pancreas, and others, through medical size diameter tubing. The ice slurry production apparatus includes a slurry production reservoir adapted to contain a volume of a saline solution. A flexible membrane crystallization surface is provided within the slurry production reservoir. The crystallization surface is chilled to a temperature below a freezing point of the saline solution within the reservoir such that ice particles form on the crystallization surface. A deflector in the form of a reciprocating member is provided for periodically distorting the crystallization surface and dislodging the ice particles which form on the crystallization surface. Using reservoir mixing the slurry is conditioned for easy pumping directly out of the production reservoir via medical tubing or delivery through other means such as squeeze bottles, squeeze bags, hypodermic syringes, manual hand delivery, and the like.

Spatiotemporal Variation in Composition of Submicron Particles in Santiago Metropolitan Region, Chile

Directory of Open Access Journals (Sweden)

Matías Tagle

2018-05-01

Full Text Available The chemical composition of submicron particles (aerodynamic diameter Da < 1.0 μm was investigated at three locations in the Santiago Metropolitan Region (SMR, Chile. Measurements campaigns were conducted in winter and spring 2016, at representative sites of a rural, urban, and urban receptor environment. Instrumentation consisted of an optical analyzer to determine Black Carbon (BC and the Aerosol Chemical Speciation Monitor (ACSM to measure concentrations of particulate chloride (Cl−, nitrate (NO3-, sulfate (SO42-, ammonium (NH4+, and non-refractory carbonaceous species (organics. Complementary data, such as ozone concentration and meteorological parameters were obtained from the public air quality network. Results showed that in both the winter and spring seasons the organics predominated in the mass of submicron particles. This fraction was followed in decreasing order by NO3-, NH4+, BC, SO42-, and Cl−. The highest average organics concentrations were measured in winter at the urban (32.2 μg m−3 and urban receptor sites (20.1 μg m−3. In winter, average concentrations of both NO3- and NH4+ were higher at the urban receptor site (12.3 and 4.5 μg m−3, respectively when compared to the urban site (6.4 and 3.1 μg m−3, respectively. In general, all the measured species were present in higher concentrations during winter, excepting SO42-, which was the only one that increased during spring. The transition toward spring was also associated with an acidification of the aerosol at the rural and urban receptor site, while at the urban site the aerosol was observed alkaline. The highest average ozone concentration during both the winter and spring seasons were recorded at the urban receptor site (7.2 and 24.0 ppb, respectively. The study reports data showing that the atmosphere in the SMR has a considerable load of particulate organic compounds, NO3- and NH4+, which are in higher concentrations at urban sites during the winter season

Fluidization mechanisms in slurry flow

Energy Technology Data Exchange (ETDEWEB)

Campbell, C. S.

1989-01-01

There are two mechanisms by which heavy settling particles may be suspended in a horizontal slurry flow: (1) by particle-particle interactions (e.g. Bagnold dispersive stresses) and (2) by particle-fluid interactions (e.g. entrainment of the particles by turbulent eddies.) The purpose of this investigation is to determine to what extent each fluidization mechanism is active and the effect of the fluidization mechanism on the global properties of the slurry. The technique employs the understanding that the particles entrained in the turbulence of the fluid will appear as an increased hydrostatic head across the channel. This may be directly measured and can be related to the fraction of the mass of particles that are supported by fluid-particle forces. (The rest must therefore be supported by particle-particle forces.) 17 refs., 26 figs.

Ice slurry applications

Energy Technology Data Exchange (ETDEWEB)

Kauffeld, M. [Karlsruhe University of Applied Sciences, Moltkestr. 30, 76133 Karlsruhe (Germany); Wang, M.J.; Goldstein, V. [Sunwell Technologies Inc., 180 Caster Avenue, Woodbridge, L4L 5Y (Canada); Kasza, K.E. [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

2010-12-15

The role of secondary refrigerants is expected to grow as the focus on the reduction of greenhouse gas emissions increases. The effectiveness of secondary refrigerants can be improved when phase changing media are introduced in place of single-phase media. Operating at temperatures below the freezing point of water, ice slurry facilitates several efficiency improvements such as reductions in pumping energy consumption as well as lowering the required temperature difference in heat exchangers due to the beneficial thermo-physical properties of ice slurry. Research has shown that ice slurry can be engineered to have ideal ice particle characteristics so that it can be easily stored in tanks without agglomeration and then be extractable for pumping at very high ice fraction without plugging. In addition ice slurry can be used in many direct contact food and medical protective cooling applications. This paper provides an overview of the latest developments in ice slurry technology. (author)

Effect of particle size distribution and concentration on flow behavior of dense slurries

Czech Academy of Sciences Publication Activity Database

Vlasák, Pavel; Chára, Zdeněk

2011-01-01

Roč. 29, č. 1 (2011), s. 53-65 ISSN 0272-6351 R&D Projects: GA ČR(CZ) GAP105/10/1574 Institutional research plan: CEZ:AV0Z20600510 Keywords : concentration effect * dense complex slurry * experimental investigation * flow behavior * particle size distribution effect * pressure drop Subject RIV: BK - Fluid Dynamics Impact factor: 0.545, year: 2011

Toward Quantifying the Mass-Based Hygroscopicity of Individual Submicron Atmospheric Aerosol Particles with STXM/NEXAFS and SEM/EDX

Science.gov (United States)

Yancey Piens, D.; Kelly, S. T.; OBrien, R. E.; Wang, B.; Petters, M. D.; Laskin, A.; Gilles, M. K.

2014-12-01

The hygroscopic behavior of atmospheric aerosols influences their optical and cloud-nucleation properties, and therefore affects climate. Although changes in particle size as a function of relative humidity have often been used to quantify the hygroscopic behavior of submicron aerosol particles, it has been noted that calculations of hygroscopicity based on size contain error due to particle porosity, non-ideal volume additivity and changes in surface tension. We will present a method to quantify the hygroscopic behavior of submicron aerosol particles based on changes in mass, rather than size, as a function of relative humidity. This method results from a novel experimental approach combining scanning transmission x-ray microscopy with near-edge x-ray absorption fine spectroscopy (STXM/NEXAFS), as well as scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM/EDX) on the same individual particles. First, using STXM/NEXAFS, our methods are applied to aerosol particles of known composition ‒ for instance ammonium sulfate, sodium bromide and levoglucosan ‒ and validated by theory. Then, using STXM/NEXAFS and SEM/EDX, these methods are extended to mixed atmospheric aerosol particles collected in the field at the DOE Atmospheric Radiation Measurement (ARM) Climate Research Facility at the Southern Great Planes sampling site in Oklahoma, USA. We have observed and quantified a range of hygroscopic behaviors which are correlated to the composition and morphology of individual aerosol particles. These methods will have implications for parameterizing aerosol mixing state and cloud-nucleation activity in atmospheric models.

Surface modification of submicronic TiO{sub 2} particles prepared by ultrasonic spray pyrolysis for visible light absorption

Energy Technology Data Exchange (ETDEWEB)

Dugandzic, Ivan M. [Institute of Technical Sciences of SASA (Serbia); Jovanovic, Dragana J. [University of Belgrade, Vinca Institute of Nuclear Sciences (Serbia); Mancic, Lidija T. [Institute of Technical Sciences of SASA (Serbia); Zheng, Nan; Ahrenkiel, Scott P. [South Dakota School of Mines and Technology (United States); Milosevic, Olivera B. [Institute of Technical Sciences of SASA (Serbia); Saponjic, Zoran V.; Nedeljkovic, Jovan M., E-mail: jovned@vinca.rs [University of Belgrade, Vinca Institute of Nuclear Sciences (Serbia)

2012-10-15

Spherical, submicronic TiO{sub 2} assemblage with high specific surface area and controllable phase composition was prepared in the process of ultrasonic spray drying/pyrolysis in a wide temperature range (150-800 Degree-Sign C) by using as a precursor aqueous colloidal solution consisting of TiO{sub 2} nanoparticles (4.5 nm). Submicronic, soft and grained spherical TiO{sub 2} particles (d = 370-500 nm) comprising clustered nanocrystals (<10 nm) were obtained at low processing temperature, while particle densification, intensive growth of the clustered primary units and anatase-to-rutile transformation ({approx}30 wt%) were observed at the higher temperatures. Detailed structural and morphological characterisation were performed by X-ray powder diffraction, scanning and field emission electron microscopy, transmission electron microscopy, and laser particle size analysis. Moreover, the surface modification of TiO{sub 2} particles through the formation of charge-transfer (CT) complex was achieved with different ligands: ascorbic acid, dopamine, catechol, 2,3-dihydroxynaphthalene, and anthrarobin. Optical properties of the surface-modified TiO{sub 2} particles were studied by using diffuse reflection spectroscopy. The binding structure between the surface titanium atoms and different ligands was determined by using Fourier transform infrared spectroscopy. The formation of CT complexes induced significant red shift of optical absorption in comparison to unmodified TiO{sub 2} particles.

Production and characterization of submicron hematite (α−Fe{sub 2}O{sub 3}) particles by ultrasonic spray pyrolysis method

Energy Technology Data Exchange (ETDEWEB)

Kırcı, Burak; Ebin, Burçak; Gürmen, Sebahattin [Department of Metallurgical and Materials Engineering, Istanbul Technical University Istanbul (Turkey)

2013-12-16

The ultrasonic spray pyrolysis (USP) method has been used to prepare submicron hematite (α−Fe{sub 2}O{sub 3}) particles using two different industrial pickling solutions of iron chloride (41 g/L FeCl{sub 2} and 54 g/L FeCl{sub 3}) Particles were obtained by thermal decomposition of generated aerosols from precursor solutions using 1.7 MHz ultrasonic atomizer. Reaction temperature was set up at 800 °C and aerosol droplets were carried into the heated zone by 0.7 L/min air flow rate. X-Ray Diffraction (XRD) studies were used to determine the crystal structure and crystallite size of the particles. Results indicate that patterns correspond to hematite phase with rhombohedral crystal structure (space group: R3c). The crystallite sizes of particles prepared from FeCl{sub 2} and FeCl{sub 3} solutions that were calculated from Scherrer equation are 59 and 33 nm, respectively. Scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS) investigations give detailed information about particle size, morphology and composition. SEM micrographs show that hematite nanoparticles aggregate and formed spherical secondary particles in submicron range.

Effects of surface chemistry on coagulation of submicron iron oxide particles (α-Fe_2O_3) in water

OpenAIRE

Liang, Liyuan

1988-01-01

Particles in the colloidal size range, i.e. smaller than 10^(-6) meter, are of interest in environmental science and many other fields of science and engineering. Since aqueous oxide particles have high specific surface areas they adsorb ions and molecules from water, and may remain stable in the aqueous phase with respect to coagulation. Submicron particles collide as a result of their thermal energy, and the effective collision rate is slowed by electric repulsion forces. A key to understan...

Slurry reactors

Energy Technology Data Exchange (ETDEWEB)

Kuerten, H; Zehner, P [BASF A.G., Ludwigshafen am Rhein (Germany, F.R.)

1979-08-01

Slurry reactors are designed on the basis of empirical data and model investigations. It is as yet not possible to calculate the flow behavior of such reactors. The swarm of gas bubbles and cluster formations of solid particles and their interaction in industrial reactors are not known. These effects control to a large extent the gas hold-up, the gas-liquid interface and, similarly as in bubble columns, the back-mixing of liquids and solids. These hydrodynamic problems are illustrated in slurry reactors which constructionally may be bubble columns, stirred tanks or jet loop reactors. The expected effects are predicted by means of tests with model systems modified to represent the conditions in industrial hydrogenation reactors. In his book 'Mass Transfer in Heterogeneous Catalysis' (1970) Satterfield complained of the lack of knowledge about the design of slurry reactors and hence of the impossible task of the engineer who has to design a plant according to accepted rules. There have been no fundamental changes since then. This paper presents the problems facing the engineer in designing slurry reactors, and shows new development trends.

Overview of slurry pipelines

Energy Technology Data Exchange (ETDEWEB)

Gandhi, R L

1982-01-01

Slurry pipelines have proven to be a technically feasible, environmentally attractive and economic method of transporting finely divided particles over long distances. A pipeline system normally consists of preparation, pipeline and utilization facilities and requires optimization of all three components taken together. A considerable amount of research work has been done to develop hydraulic design of a slurry pipeline. Equipment selection and estimation of corrosion-erosion are considered to be as important as the hydraulic design. Future applications are expected to be for the large-scale transport of coal and for the exploitation of remotely located mineral deposits such as iron ore and copper. Application of slurry pipelines for the exploitation of remotely located mineral deposits is illustrated by the Kudremukh iron concentrate slurry pipeline in India.

Technical Development of Slurry Three-Dimensional Printer

Science.gov (United States)

Jiang, Cho-Pei; Hsu, Huang-Jan; Lee, Shyh-Yuan

2017-09-01

The aim of this paper is to review the technical development of slurry three-dimensional printer (3DP) which based on photo-polymerization and constrained surface method. Basically, slurry consists of ceramic powder, resin and photo-initiator. The light engines for solidifying the photo-curable slurry can be classified as laser, liquid crystal panel (LCD), digital light processing (DLP). The slurry can be reacted and solidified by selective ray according to the reaction spectrum of photo-initiator. Ceramic powder used in this study is zirconia oxide. Experimental results show that ceramic particle size affects the viscosity of slurry severely resulting in low accuracy and the occurrence of micro crack in the layer casting procedure. Therefore, the effect of particle size on the curability and accuracy of built green part is discussed. A single dental crown is proposed to be fabricated by these three light engines as a benchmark for comparison. In addition, the cost and the limitation are compared in the aspect of dental crown fabrication. Consequently, the lowest cost is LCD-type slurry 3DP system. DLP-type slurry 3DP can produce green body with the fastest fabrication time. The volumetric error of sintered part that made by these three fabrication methods is similar because the composition of slurry is the same.

Numerical Investigation of Ice Slurry Flow in a Horizontal Pipe

Science.gov (United States)

Rawat, K. S.; Pratihar, A. K.

2018-02-01

In the last decade, phase changing material slurry (PCMS) gained much attention as a cooling medium due to its high energy storage capacity and transportability. However the flow of PCM slurry is a complex phenomenon as it affected by various parameters, i.e. fluid properties, velocity, particle size and concentration etc.. In the present work ice is used as a PCM and numerical investigation of heterogeneous slurry flow has been carried out using Eulerian KTGF model in a horizontal pipe. Firstly the present model is validated with existing experiment results available in the literature, and then model is applied to the present problem. Results show that, flow is almost homogeneous for ethanol based ice slurry with particle diameter of 0.1 mm at the velocity of 1 m/s. It is also found that ice particle distribution is more uniform at higher velocity, concentration of ice and ethanol in slurry. Results also show that ice concentration increases on the top of the pipe, and the effect of particle wall collision is more significant at higher particle diameter.

Numerical simulation of white double-layer coating with different submicron particles on the spectral reflectance

International Nuclear Information System (INIS)

Chai, Jiale; Cheng, Qiang; Si, Mengting; Su, Yang; Zhou, Yifan; Song, Jinlin

2017-01-01

The spectral selective coating is becoming more and more popular against solar irradiation not only in keeping the coated objects stay cool but also retain the appearance of the objects by reducing the glare of reflected sunlight. In this work a numerical study is investigated to design the double-layer coating with different submicron particles to achieve better performance both in thermal and aesthetic aspects. By comparison, the performance of double-layer coating with TiO_2 and ZnO particles is better than that with single particles. What's more, the particle diameter, volume fraction of particle as well as substrate condition is also investigated. The results show that an optimized double-layer coating with particles should be the one with an appropriate particle diameter, volume fraction and the black substrate. - Highlights: • The double-layer coating has a great influence on both thermal and aesthetic aspects. • The double-layer coating performs better than the uniform one with single particles. • The volume fraction, particle diameter and substrate conditions are optimized.

Testing of In-Line Slurry Monitors and Pulsair Mixers with Radioactive Slurries

Energy Technology Data Exchange (ETDEWEB)

Hylton, T.D.; Bayne, C.K.

1999-08-01

Three in-line slurry monitoring instruments were demonstrated, tested, and evaluated for their capability to determine the transport properties of radioactive slurries. The instruments included the Endress + Hauser Promass 63M Coriolis meter for measuring density, the Lasentec M600P for measuring particle size distribution, and a prototype ultrasonic monitor that was developed by Argonne National Laboratory for measuring suspended solids concentration. In addition, the power consumption of the recirculation pump was monitored to determine whether this parameter could be used as a tool for in-line slurry monitoring. The Promass 63M and the M600P were also evaluated as potential indicators of suspended solids concentration. In order to use the Promass 63M as a suspended solids monitor, the densities of the fluid phase and the dry solid particle phase must be known. In addition, the fluid phase density and the dry solids density must remain constant, as any change will affect the correlation between the slurry density and the suspended solids concentration. For the M600P, the particle size distribution would need to remain relatively constant. These instruments were demonstrated and tested at the Gunite and Associated Tanks Remediation Project at the Oak Ridge National Laboratory. The testing of the instruments was conducted in parallel with the testing of a Pulsair mixing system, which was used to mix the contents of the selected tank. A total of six tests were performed. A submersible pump was positioned at two depths, while the Pulsair system was operated at three mixing rates.

Investigations into the penetration and pressure drop of HEPA filter media during loading with submicron particle aerosols at high concentrations

International Nuclear Information System (INIS)

Leibold, H; Wilhelm, J.G.

1991-01-01

High Efficiency Particulate Air (HEPA) filters are typically employed in particle removal and retention within the air cleaning systems of clean rooms in the pharmaceutical, nuclear and semiconductor industries for dust concentrations of some μg/m 3 . Their extremely high removal efficiencies for submicron particles make them attractive candidates in complying with increasingly lower emission limits for industrial processes that involve dust concentrations of up to several g/m 3 . Cost-effective operation under such conditions requires the filter units to be recleanable. The recleanability of HEPA filter media depends not only on the operating conditions during the cleaning process but also on the filtration conditions during particle loading. The structure and location of the particles captured by the glass fiber matrix greatly affect the degree to which they can be subsequently dislodged and removed from the filter medium. Changes in filtration efficiency with service time for various particle diameters in the critical submicron size range, as well as the effects of filtration velocity on the increase in pressure drop, are important criteria with regard to recleaning HEPA filter units. Of special significance for the recleanability of HEPA filter media is knowledge of how operating conditions affect dust cake formation. (author)

Development of Short Range Repulsive Inter-Particle Forces in Aqueous Si3N4 Slurries with Chem-Adsorbed Silanes

National Research Council Canada - National Science Library

Colic, Miroslav

1997-01-01

.... Addition of salt to dispersed silicon nitride slurries with particles coated with polyethyleneglycol-silane, caused the collapse of the 22 atoms long chains and residual electrical double layer...

Effective immobilization of glucose oxidase on chitosan submicron particles from gladius of Todarodes pacificus for glucose sensing.

Science.gov (United States)

Anusha, J R; Fleming, Albin T; Kim, Hee-Je; Kim, Byung Chul; Yu, Kook-Hyun; Raj, C Justin

2015-08-01

An effective enzymatic glucose biosensor was developed by immobilizing glucose oxidase on chitosan submicron particles synthesized from the gladius of Todarodes pacificus (GCSP). The chemically synthesized chitosan from gladius was pulverized to submicron particles by ball milling technique, which was further characterized and compared with the standard chitosan (SCS). The degree of deacetylation of GCSP was determined using FTIR spectroscopy which was comparable to the value of standard chitosan. The glucose oxidase (GOx) was immobilized over GCSP on porous zinc oxide/platinum nanoparticle (ZnO/Pt) based electrode. The morphological and structural properties of the electrodes were analyzed using scanning electron microscopy and X-ray diffraction analysis. The glucose sensing behavior of electrode was estimated using electrochemical analysis and showed an excellent analytical performance. The electrode ZnO/Pt/GCSP conjugated with GOx displayed high sensitivity (88.76 μA mM(-1) cm(-2)) with low detection limit in short response time. In addition, the very low value of Michaelis-Menten constant for GCSP based electrode contributes a better affinity of the electrode surface towards glucose oxidase. Copyright © 2015 Elsevier B.V. All rights reserved.

Engineering properties of nuclear waste slurries - 16378

International Nuclear Information System (INIS)

Biggs, Simon; Fairweather, Michael; Hunter, Timothy; Omokanye, Qanitalillahi; Peakall, Jeffrey

2009-01-01

The type of particulate systems encountered in legacy nuclear waste slurries is highly complicated, with the aggregation and flow behaviour being at times very variable. However, deconstructing the complex overall slurry activity to singular particle-particle interactions can lead to a greater understanding of the mechanisms involved with particle aggregation, and so to predictions of their settling and flow in nuclear systems. Of particular importance to legacy waste is the role of salts in controlling the attraction of particles (and so in dictating the rheological properties of the system) as sludge may contain a variety of specific ions and generally have high ionic conductivity [1]. In this paper, particle-particle interactions are characterised using a number of complimentary methods, and their influence on resulting flow and bed compression is measured. The methods used to characterise the particle-particle interactions under various salt and pH conditions were electro-acoustic analysis (zeta potential) and atomic force microscopy (AFM). Following on from the analysis of particle-particle properties, bulk sediment behaviour was investigated using shear and compressive yield stress measurements, vital parameters in dictating flow and dewatering performance, respectively. Together, these techniques enable the characterisation of a range of particulate systems that may be encountered in legacy wastes, and results point to a number of important factors that can help explain the observed variability in industrial slurry behaviour. (authors)

Hybrid micro-particles as a magnetically-guidable decontaminant for cesium-eluted ash slurry

Science.gov (United States)

Namiki, Yoshihisa; Ueyama, Toshihiko; Yoshida, Takayuki; Watanabe, Ryoei; Koido, Shigeo; Namiki, Tamami

2014-09-01

Decontamination of the radioactive cesium that is widely dispersed owing to a nuclear power station accident and concentrated in fly ash requires an effective elimination system. Radioactive fly ash contains large amounts of water-soluble cesium that can cause severe secondary contamination and represents a serious health risk, yet its complete removal is complicated and difficult. Here it is shown that a new fine-powder formulation can be magnetically guided to eliminate cesium after being mixed with the ash slurry. This formulation, termed MagCE, consists of a ferromagnetic porous structure and alkaline- and salt-resistant nickel ferrocyanide. It has potent cesium-adsorption- and magnetic-separation-properties. Because of its resistance against physical and chemical attack such as with ash particles, as well as with the high pH and salt concentration of the ash slurry, MagCE simplifies the decontamination process without the need of the continued presence of the hazardous water-soluble cesium in the treated ash.

Water ice and sub-micron ice particles on Tethys and Mimas

Science.gov (United States)

Scipioni, Francesca; Nordheim, Tom; Clark, Roger Nelson; D'Aversa, Emiliano; Cruikshank, Dale P.; Tosi, Federico; Schenk, Paul M.; Combe, Jean-Philippe; Dalle Ore, Cristina M.

2017-10-01

IntroductionWe present our ongoing work, mapping the variation of the main water ice absorption bands, and the distribution of the sub-micron particles, across Mimas and Tethys’ surfaces using Cassini-VIMS cubes acquired in the IR range (0.8-5.1 μm). We present our results in the form of maps of variation of selected spectral indicators (depth of absorption bands, reflectance peak height, spectral slopes).Data analysisVIMS acquires hyperspectral data in the 0.3-5.1 μm spectral range. We selected VIMS cubes of Tethys and Mimas in the IR range (0.8-5.1 μm). For all pixels in the selected cubes, we measured the band depths for water-ice absorptions at 1.25, 1.5 and 2.02 μm and the height of the 3.6 μm reflection peak. Moreover, we considered the spectral indictors for particles smaller than 1 µm [1]: (i) the 2 µm absorption band is asymmetric and (ii) it has the minimum shifted to longer λ (iii) the band depth ratio 1.5/2.0 µm decreases; (iv) the reflection peak at 2.6 µm decreases; (v) the Fresnel reflection peak is suppressed; (vi) the 5 µm reflectance is decreased relative to the 3.6 µm peak. To characterize the global variation of water-ice band depths, and of sub-micron particles spectral indicators, across Mimas and Tethys, we sampled the two satellites’ surfacees with a 1°x1° fixed-resolution grid and then averaged the band depths and peak values inside each square cell.3. ResultsFor both moons we find that large geologic features, such as the Odysseus and Herschel impact basins, do not correlate with water ice’s abundance variation. For Tethys, we found a quite uniform surface on both hemispheres. The only deviation from this pattern shows up on the trailing hemisphere, where we notice two north-oriented, dark areas around 225° and 315°. For Mimas, the leading and trailing hemispheres appear to be quite similar in water ice abundance, the trailing portion having water ice absorption bands lightly more suppressed than the leading side

Development of a phenomenological model for coal slurry atomization

Energy Technology Data Exchange (ETDEWEB)

Dooher, J.P. [Adelphi Univ., Garden City, NY (United States)

1995-11-01

Highly concentrated suspensions of coal particles in water or alternate fluids appear to have a wide range of applications for energy production. For enhanced implementation of coal slurry fuel technology, an understanding of coal slurry atomization as a function coal and slurry properties for specific mechanical configurations of nozzle atomizers should be developed.

Separation of submicron particles from biofuel combustion with flue gas condensation or wet condensing electrostatic precipitator. Analysis of possibilities; Avskiljning av submikrona partiklar vid biobraenslefoerbraenning med roekgaskondensering eller kondenserande vaata elfilter. Analys av moejligheterna

Energy Technology Data Exchange (ETDEWEB)

Roennbaeck, Marie; Gustavsson, Lennart [Swedish National Testing and Research Inst., Boraas (Sweden)

2006-11-15

Dust particles in flue gas larger than 1 {mu}m are well separated by conventional techniques, while submicron particles are poorly separated. As the use of biofuels with high ash content is increasing, as well as knowledge about negative health effects from inhalation of submicron particles, the interest for reduction of emissions of submicron particles will probably increase. The aim of this project is to investigate possible techniques for separation of submicron particles during flue gas condensation through modification of conventional technique, or with available techniques not usually used with combustion of biofuels, e.g. a wet electrostatic precipitator. Mechanisms for separation of dust particles are briefly described. Cyclones separates particles larger than about 1 {mu}m. Fabric filters separates all particles sizes, but the efficiency reduces as the size reduces. In flue gas condensers and scrubbers the speed and size of water droplets are important for the reduction efficiency. Dry electrostatic precipitators work for all particle sizes, but with reduced efficiency for sizes between 0.1 and 3 {mu}m. Wet electrostatic precipitators separates submicron particles much better. One reason for this is that the potential between the electrodes can be higher. Among conventional flue gas condensers and scrubbers there are two types that, properly designed, can separate submicron particles, namely 'type venturi scrubbers', i.e. a scrubber where a high flue gas velocity is used to form many, small water droplets by friction forces in a nozzle, and 'type scrubber with nozzles', i.e. a scrubber where nozzles supply droplets to the flue gas. For a scrubber with nozzles, the falling velocity of the droplets must be lower and the size smaller than is common today. Also the wet electrostatic precipitator separates submicron particles with high efficiency. They are used today mainly for problematic particles, e.g. sticky or corrosive ones, or for

Aerosols in the tropical and subtropical UT/LS: in-situ measurements of submicron particle abundance and volatility

Directory of Open Access Journals (Sweden)

S. Borrmann

2010-06-01

Full Text Available Processes occurring in the tropical upper troposphere (UT, the Tropical Transition Layer (TTL, and the lower stratosphere (LS are of importance for the global climate, for stratospheric dynamics and air chemistry, and for their influence on the global distribution of water vapour, trace gases and aerosols. In this contribution we present aerosol and trace gas (in-situ measurements from the tropical UT/LS over Southern Brazil, Northern Australia, and West Africa. The instruments were operated on board of the Russian high altitude research aircraft M-55 "Geophysica" and the DLR Falcon-20 during the campaigns TROCCINOX (Araçatuba, Brazil, February 2005, SCOUT-O3 (Darwin, Australia, December 2005, and SCOUT-AMMA (Ouagadougou, Burkina Faso, August 2006. The data cover submicron particle number densities and volatility from the COndensation PArticle counting System (COPAS, as well as relevant trace gases like N₂O, ozone, and CO. We use these trace gas measurements to place the aerosol data into a broader atmospheric context. Also a juxtaposition of the submicron particle data with previous measurements over Costa Rica and other tropical locations between 1999 and 2007 (NASA DC-8 and NASA WB-57F is provided. The submicron particle number densities, as a function of altitude, were found to be remarkably constant in the tropical UT/LS altitude band for the two decades after 1987. Thus, a parameterisation suitable for models can be extracted from these measurements. Compared to the average levels in the period between 1987 and 2007 a slight increase of particle abundances was found for 2005/2006 at altitudes with potential temperatures, Θ, above 430 K. The origins of this increase are unknown except for increases measured during SCOUT-AMMA. Here the eruption of the Soufrière Hills volcano in the Caribbean caused elevated particle mixing ratios. The vertical profiles from Northern hemispheric mid-latitudes between 1999 and 2006 also are

Sub-micron filter

Science.gov (United States)

Tepper, Frederick [Sanford, FL; Kaledin, Leonid [Port Orange, FL

2009-10-13

Aluminum hydroxide fibers approximately 2 nanometers in diameter and with surface areas ranging from 200 to 650 m.sup.2/g have been found to be highly electropositive. When dispersed in water they are able to attach to and retain electronegative particles. When combined into a composite filter with other fibers or particles they can filter bacteria and nano size particulates such as viruses and colloidal particles at high flux through the filter. Such filters can be used for purification and sterilization of water, biological, medical and pharmaceutical fluids, and as a collector/concentrator for detection and assay of microbes and viruses. The alumina fibers are also capable of filtering sub-micron inorganic and metallic particles to produce ultra pure water. The fibers are suitable as a substrate for growth of cells. Macromolecules such as proteins may be separated from each other based on their electronegative charges.

Rheology of oil sands slurries

Energy Technology Data Exchange (ETDEWEB)

Chow, R.; Zhou, J. [Alberta Research Council, Edmonton, AB (Canada). Mineral Oil Sands Unit; Wallace, D. [Dean Wallace Consulting Inc., Beaumont, AB (Canada)

2006-07-01

This study focused on integrating rheology and colloid science to improve recovery of bitumen in surface mined oil sands. Factors that influence recovery, such as conditions of particle interaction, solids concentration and shear rate, were reviewed. In an effort to understand the rheological behaviour of clay-in-water suspensions, an elaborate procedure was developed to separate an inter-bedded clay layer from a site at Albian Sands Energy Inc. The variables were water chemistry, solids concentration, and shear rate. The research study was conducted at the Alberta Research Council with the support of the CONRAD Extraction Group. A controlled stress rheometer was used to provide the quantitative evaluations of the clay slurry properties. The research results indicate that the viscoelastic properties of the slurry are highly influenced by the shear history of the slurry, solids content, calcium concentration, and sample aging. Shear thinning behaviour was observed in all slurry samples, but the slurry viscosity increased with test time for a given shear rate. In order to classify the slurries, a method was developed to distinguish the gel strength. The slurries were then classified into 3 distinct patterns, including no gel, weak gel and strong gel. The evolution of the experimental protocols were described along with the current stability maps that correlate the domains of the gel strength according to the solids concentration, calcium ion content, and shear rate. It was concluded that the rheological properties of oil sands slurries influence bitumen recovery in commercial surface-mined oil sands operations. tabs., figs.

Dynamic NMR Study of Model CMP Slurry Containing Silica Particles as Abrasives

Science.gov (United States)

Odeh, F.; Al-Bawab, A.; Li, Y.

2018-02-01

Chemical mechanical planarization (CMP) should provide a good surface planarity with minimal surface defectivity. Since CMP slurries are multi-component systems, it is very important to understand the various processes and interactions taking place in such slurries. Several techniques have been employed for such task, however, most of them lack the molecular recognition to investigate molecular interactions without adding probes which in turn increase complexity and might alter the microenvironment of the slurry. Nuclear magnetic resonance (NMR) is a powerful technique that can be employed in such study. The longitudinal relaxation times (T1) of the different components of CMP slurries were measured using Spin Echo-NMR (SE-NMR) at a constant temperature. The fact that NMR is non-invasive and gives information on the molecular level gives more advantage to the technique. The model CMP slurry was prepared in D2O to enable monitoring of T1 for the various components' protons. SE-NMR provide a very powerful tool to study the various interactions and adsorption processes that take place in a model CMP silica based slurry which contains BTA and/or glycine and/or Cu+2 ions. It was found that BTA is very competitive towards complexation with Cu+2 ions and BTA-Cu complex adsorbs on silica surface.

Deposition Velocities of Newtonian and Non-Newtonian Slurries in Pipelines

Energy Technology Data Exchange (ETDEWEB)

Poloski, Adam P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Adkins, Harold E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Abrefah, John [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Casella, Andrew M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hohimer, Ryan E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Nigl, Franz [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Minette, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Toth, James J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tingey, Joel M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Yokuda, Satoru T. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2009-03-01

The WTP pipe plugging issue, as stated by the External Flowsheet Review Team (EFRT) Executive Summary, is as follows: “Piping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging.” A strategy was employed to perform critical-velocity tests on several physical simulants. Critical velocity is defined as the point where a stationary bed of particles deposits on the bottom of a straight horizontal pipe during slurry transport operations. Results from the critical velocity testing provide an indication of slurry stability as a function of fluid rheological properties and transport conditions. The experimental results are compared to the WTP design guide on slurry transport velocity in an effort to confirm minimum waste velocity and flushing velocity requirements as established by calculations and critical line velocity correlations in the design guide. The major findings of this testing is discussed below. Experimental results indicate that the use of the Oroskar and Turian (1980) correlation in the design guide is conservative—Slurry viscosity has a greater affect on particles with a large surface area to mass ratio. The increased viscous forces on these particles result in a decrease in predicted critical velocities from this traditional industry derived equations that focus on particles large than 100 μm in size. Since the Hanford slurry particles generally have large surface area to mass ratios, the reliance on such equations in the Hall (2006) design guide is conservative. Additionally, the use of the 95% percentile particle size as an input to this equation is conservative. However, test results indicate that the use of an average particle density as an input to the equation is not conservative. Particle density has a large influence on the overall result returned by the correlation. Lastly, the viscosity

Indoor and Outdoor Levels and Sources of Submicron Particles (PM1) at Homes in Edmonton, Canada.

Science.gov (United States)

Bari, Md Aynul; Kindzierski, Warren B; Wallace, Lance A; Wheeler, Amanda J; MacNeill, Morgan; Héroux, Marie-Ève

2015-06-02

Exposure to submicron particles (PM1) is of interest due to their possible chronic and acute health effects. Seven consecutive 24-h PM1 samples were collected during winter and summer 2010 in a total of 74 nonsmoking homes in Edmonton, Canada. Median winter concentrations of PM1 were 2.2 μg/m(3) (interquartile range, IQR = 0.8-6.1 μg/m(3)) and 3.3 μg/m(3) (IQR = 1.5-6.9 μg/m(3)) for indoors and outdoors, respectively. In the summer, indoor (median 4.4 μg/m(3), IQR = 2.4-8.6 μg/m(3)) and outdoor (median 4.3 μg/m(3), IQR = 2.6-7.4 μg/m(3)) levels were similar. Positive matrix factorization (PMF) was applied to identify and apportion indoor and outdoor sources of elements in PM1 mass. Nine sources contributing to both indoor and outdoor PM1 concentrations were identified including secondary sulfate, soil, biomass smoke and environmental tobacco smoke (ETS), traffic, settled and mixed dust, coal combustion, road salt/road dust, and urban mixture. Three additional indoor sources were identified i.e., carpet dust, copper-rich, and silver-rich. Secondary sulfate, soil, biomass smoke and ETS contributed more than 70% (indoors: 0.29 μg/m(3), outdoors: 0.39 μg/m(3)) of measured elemental mass in PM1. These findings can aid understanding of relationships between submicron particles and health outcomes for indoor/outdoor sources.

The influence of adsorption capacity on enhanced gas absorption in activated carbon slurries

NARCIS (Netherlands)

Holstvoogd, R.D.; van Swaaij, Willibrordus Petrus Maria

1990-01-01

The enhanced absorption of gases in aqueous activated carbbon slurries of fine particles is studied with a non-steady-state absorption model, taking into account the finite adsorption capacity of the carbon particles. It has been found that, for the different gas/activated carbon slurry systems

Radical change of Zn speciation in pig slurry amended soil: Key role of nano-sized sulfide particles.

Science.gov (United States)

Formentini, Thiago Augusto; Legros, Samuel; Fernandes, Cristovão Vicente Scapulatempo; Pinheiro, Adilson; Le Bars, Maureen; Levard, Clément; Mallmann, Fábio Joel Kochem; da Veiga, Milton; Doelsch, Emmanuel

2017-03-01

Spreading livestock manure as fertilizer on farmlands is a widespread practice. It represents the major source of heavy metal(loid)s (HM) input in agricultural soils. Since zinc (Zn) is present at high concentrations in manure, it poses special environmental concerns related to phytotoxicity, groundwater contamination, and introduction in the food chain. Therefore, investigations on the fate and behavior of manure-borne Zn, when it enters the soil environment, are necessary to predict the environmental effects. Nevertheless, long-term field studies assessing Zn speciation in the organic waste matrix, as well as within the soil after manure application, are lacking. This study was designed to fill this gap. Using SEM-EDS and XAS analysis, we reported the following new results: (i) ZnS made up 100% of the Zn speciation in the pig slurry (the highest proportion of ZnS ever observed in organic waste); and (ii) ZnS aggregates were about 1-μm diameter (the smallest particle size ever reported in pig slurry). Moreover, the pig slurry containing ZnS was spread on the soil over an 11-year period, totaling 22 applications, and the resulting Zn speciation within the amended soil was analyzed. Surprisingly, ZnS, i.e. the only species responsible for a nearly 2-fold increase in the Zn concentration within the amended soil, was not detected in this soil. Based on SEM-EDS and XAS observations, we put forward the hypothesis that Zn in the pig slurry consisted of nano-sized ZnS crystallites that further aggregated. The low stability of ZnS nanoparticles within oxic and complex environments such as the studied soil was the key explanation for the radical change in pig slurry-borne Zn speciation after long-term amendments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparative testing of slurry monitors

International Nuclear Information System (INIS)

Hylton, T.D.; Bayne, C.K.; Anderson, M.S.; Van Essen, D.C.

1998-05-01

The US Department of Energy (DOE) has millions of gallons of radioactive liquid and sludge wastes that must be retrieved from underground storage tanks, transferred to treatment facilities, and processed to a final waste form. The wastes will be removed from the current storage tanks by mobilizing the sludge wastes and mixing them with the liquid wastes to create slurries. Each slurry would then be transferred by pipeline to the desired destination. To reduce the risk of plugging a pipeline, the transport properties (e.g., density, suspended solids concentration, viscosity, particle size range) of the slurry should be determined to be within acceptable limits prior to transfer. These properties should also be monitored and controlled within specified limits while the slurry transfer is in progress. The DOE issued a call for proposals for developing on-line instrumentation to measure the transport properties of slurries. In response to the call for proposals, several researchers submitted proposals and were funded to develop slurry monitoring instruments. These newly developed DOE instruments are currently in the prototype stage. Before the instruments were installed in a radioactive application, the DOE wanted to evaluate them under nonradioactive conditions to determine if they were accurate, reliable, and dependable. The goal of this project was to test the performance of the newly developed DOE instruments along with several commercially available instruments. The baseline method for comparison utilized the results from grab-sample analyses

Slurry walls and slurry trenches - construction quality control

International Nuclear Information System (INIS)

Poletto, R.J.; Good, D.R.

1997-01-01

Slurry (panel) walls and slurry trenches have become conventional methods for construction of deep underground structures, interceptor trenches and hydraulic (cutoff) barriers. More recently polymers mixed with water are used to stabilize the excavation instead of bentonite slurry. Slurry walls are typically excavated in short panel segments, 2 to 7 m (7 to 23 ft) long, and backfilled with structural materials; whereas slurry trenches are fairly continuous excavations with concurrent backfilling of blended soils, or cement-bentonite mixtures. Slurry trench techniques have also been used to construct interceptor trenches. Currently no national standards exist for the design and/or construction of slurry walls/trenches. Government agencies, private consultants, contractors and trade groups have published specifications for construction of slurry walls/trenches. These specifications vary in complexity and quality of standards. Some place excessive emphasis on the preparation and control of bentonite or polymer slurry used for excavation, with insufficient emphasis placed on quality control of bottom cleaning, tremie concrete, backfill placement or requirements for the finished product. This has led to numerous quality problems, particularly with regard to identification of key depths, bottom sediments and proper backfill placement. This paper will discuss the inspection of slurry wall/trench construction process, identifying those areas which require special scrutiny. New approaches to inspection of slurry stabilized excavations are discussed

Development and scintigraphic evaluation of submicron sized dry powder inhalation formulation of fluticasone propionate in healthy human volunteers

International Nuclear Information System (INIS)

Ali, Sultana S.; Ahmad, F.J.; Khar, R.K.; Rathore, V.P.; Ali, Rashid; Rawat, H.S.; Chopra, M.K.; Mittal, G.; Bhatnagar, A.

2010-01-01

Full text: Objective of the present study concerns formulation and evaluation of submicron sized dry powder inhalation formulation of Fluticasone propionate for the treatment of bronchial asthma, COPD and a new life saving treatment option in restrictive lung diseases such as Interstitial Lung Disease (ILD), toxic and non-cardiogenic pulmonary inflammations or pulmonary edema, which have no effective treatment presently. Materials and Methods: The submicron sized particles were prepared by precipitation method using acetone as solvent and water as antisolvent. Poloxamer F127 was used as stabilizer. Both submicronized and micronized particles were characterized using FTIR, XRD, DSC, SEM and TEM. The mass median aerodynamic diameter (MMAD) of the submicronized and micronized API was calculated using Andersen cascade impactor. The prepared particles and micronized Active Pharmaceutical Ingredient (API) were radiolabeled with 99m Tc. Size3 HPMC capsules were filled with the 12.5 mg radiolabeled blend (100μg Fluticasone propionate and 12.4mg inhalable lactose) and given to healthy volunteers to assess the comparative pulmonary deposition. Results: The prepared formulation has shown better lung deposition as compared to micronized API. The MMAD of submicronized particles was in the range of 1 - 5 μm while the MMAD of micronized API was in the range of 5 - 15μm. Conclusion: The developed submicron sized dry powder inhalation formulation has better lung deposition as compared to micron sized API and it will become a better treatment option for the bronchial asthma, COPD and ILDs

Superheated fuel injection for combustion of liquid-solid slurries

Science.gov (United States)

Robben, F.A.

1984-10-19

A method and device are claimed for obtaining, upon injection, flash evaporation of a liquid in a slurry fuel to aid in ignition and combustion. The device is particularly beneficial for use of coal-water slurry fuels in internal combustion engines such as diesel engines and gas turbines, and in external combustion devices such as boilers and furnaces. The slurry fuel is heated under pressure to near critical temperature in an injector accumulator, where the pressure is sufficiently high to prevent boiling. After injection into a combustion chamber, the water temperature will be well above boiling point at a reduced pressure in the combustion chamber, and flash boiling will preferentially take place at solid-liquid surfaces, resulting in the shattering of water droplets and the subsequent separation of the water from coal particles. This prevents the agglomeration of the coal particles during the subsequent ignition and combustion process, and reduces the energy required to evaporate the water and to heat the coal particles to ignition temperature. The overall effect will be to accelerate the ignition and combustion rates, and to reduce the size of the ash particles formed from the coal. 2 figs., 2 tabs.

Sub-micron particle number size distribution characteristics at two urban locations in Leicester

Science.gov (United States)

Hama, Sarkawt M. L.; Cordell, Rebecca L.; Kos, Gerard P. A.; Weijers, E. P.; Monks, Paul S.

2017-09-01

The particle number size distribution (PNSD) of atmospheric particles not only provides information about sources and atmospheric processing of particles, but also plays an important role in determining regional lung dose. Owing to the importance of PNSD in understanding particulate pollution two short-term campaigns (March-June 2014) measurements of sub-micron PNSD were conducted at two urban background locations in Leicester, UK. At the first site, Leicester Automatic Urban Rural Network (AURN), the mean number concentrations of nucleation, Aitken, accumulation modes, the total particles, equivalent black carbon (eBC) mass concentrations were 2002, 3258, 1576, 6837 # cm-3, 1.7 μg m-3, respectively, and at the second site, Brookfield (BF), were 1455, 2407, 874, 4737 # cm-3, 0.77 μg m-3, respectively. The total particle number was dominated by the nucleation and Aitken modes, with both consisting of 77%, and 81% of total number concentrations at AURN and BF sites, respectively. This behaviour could be attributed to primary emissions (traffic) of ultrafine particles and the temporal evolution of mixing layer. The size distribution at the AURN site shows bimodal distribution at 22 nm with a minor peak at 70 nm. The size distribution at BF site, however, exhibits unimodal distribution at 35 nm. This study has for the first time investigated the effect of Easter holiday on PNSD in UK. The temporal variation of PNSD demonstrated a good degree of correlation with traffic-related pollutants (NOX, and eBC at both sites). The meteorological conditions, also had an impact on the PNSD and eBC at both sites. During the measurement period, the frequency of NPF events was calculated to be 13.3%, and 22.2% at AURN and BF sites, respectively. The average value of formation and growth rates of nucleation mode particles were 1.3, and 1.17 cm-3 s-1 and 7.42, and 5.3 nm h-1 at AURN, and BF sites, respectively. It can suggested that aerosol particles in Leicester originate mainly

Process for heating coal-oil slurries

Science.gov (United States)

Braunlin, W.A.; Gorski, A.; Jaehnig, L.J.; Moskal, C.J.; Naylor, J.D.; Parimi, K.; Ward, J.V.

1984-01-03

Controlling gas to slurry volume ratio to achieve a gas holdup of about 0.4 when heating a flowing coal-oil slurry and a hydrogen containing gas stream allows operation with virtually any coal to solvent ratio and permits operation with efficient heat transfer and satisfactory pressure drops. The critical minimum gas flow rate for any given coal-oil slurry will depend on numerous factors such as coal concentration, coal particle size distribution, composition of the solvent (including recycle slurries), and type of coal. Further system efficiency can be achieved by operating with multiple heating zones to provide a high heat flux when the apparent viscosity of the gas saturated slurry is highest. Operation with gas flow rates below the critical minimum results in system instability indicated by temperature excursions in the fluid and at the tube wall, by a rapid increase and then decrease in overall pressure drop with decreasing gas flow rate, and by increased temperature differences between the temperature of the bulk fluid and the tube wall. At the temperatures and pressures used in coal liquefaction preheaters the coal-oil slurry and hydrogen containing gas stream behaves essentially as a Newtonian fluid at shear rates in excess of 150 sec[sup [minus]1]. The gas to slurry volume ratio should also be controlled to assure that the flow regime does not shift from homogeneous flow to non-homogeneous flow. Stable operations have been observed with a maximum gas holdup as high as 0.72. 29 figs.

The role of adsorbed water on the friction of a layer of submicron particles

Science.gov (United States)

Sammis, Charles G.; Lockner, David A.; Reches, Ze’ev

2011-01-01

Anomalously low values of friction observed in layers of submicron particles deformed in simple shear at high slip velocities are explained as the consequence of a one nanometer thick layer of water adsorbed on the particles. The observed transition from normal friction with an apparent coefficient near μ = 0.6 at low slip speeds to a coefficient near μ = 0.3 at higher slip speeds is attributed to competition between the time required to extrude the water layer from between neighboring particles in a force chain and the average lifetime of the chain. At low slip speeds the time required for extrusion is less than the average lifetime of a chain so the particles make contact and lock. As slip speed increases, the average lifetime of a chain decreases until it is less than the extrusion time and the particles in a force chain never come into direct contact. If the adsorbed water layer enables the otherwise rough particles to rotate, the coefficient of friction will drop to μ = 0.3, appropriate for rotating spheres. At the highest slip speeds particle temperatures rise above 100°C, the water layer vaporizes, the particles contact and lock, and the coefficient of friction rises to μ = 0.6. The observed onset of weakening at slip speeds near 0.001 m/s is consistent with the measured viscosity of a 1 nm thick layer of adsorbed water, with a minimum particle radius of approximately 20 nm, and with reasonable assumptions about the distribution of force chains guided by experimental observation. The reduction of friction and the range of velocities over which it occurs decrease with increasing normal stress, as predicted by the model. Moreover, the analysis predicts that this high-speed weakening mechanism should operate only for particles with radii smaller than approximately 1 μm. For larger particles the slip speed required for weakening is so large that frictional heating will evaporate the adsorbed water and weakening will not occur.

Exposure to submicron particles (PM1.0) from diesel exhaust and pollen allergens of human lung epithelial cells induces morphological changes of mitochondria tonifilaments and rough endoplasmic reticulum.

Science.gov (United States)

Mazzarella, Gennaro; Lucariello, Angela; Bianco, Andrea; Calabrese, Cecilia; Thanassoulas, Theodoros; Savarese, Leonilde; Fiumarella, Angelamaria; Esposito, Vincenzo; DE Luca, Antonio

2014-01-01

In recent literature, little has been said regarding the morphological changes that occur in lung cells after treatment with particles and nanoparticles. Using an in vitro model of type-II lung epithelium (A549), we studied the effects of submicron particles (PM1.0), Parietaria officinalis (ALL), and PM1.0 + ALL together. To date several biochemical effects have been described, instead few data exist in literature regarding morphological events following these treatments, in particular we focused on the morphological changes and distribution of mitochondria, tonifilaments and rough endoplasmic reticulum, using a transmission electron microscopic (TEM) approach. After exposure to PM1.0 particles (PM1.0), Parietaria officinalis as allergen, and PM1.0 with P. officinalis, changes in the cytoplasmic area were observed, such as damage to mitochondria and morphological alterations of the tonifilaments and rough endoplasmic reticulum. The data obtained strongly support the hypothesis that cells in contact with submicron particles (PM1.0), or P. officinalis, undergo alteration of their metabolism. Copyright © 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Investigation of aqueous slurries as fusion reactor blankets

International Nuclear Information System (INIS)

Schuller, M.J.

1985-01-01

Numerical and experimental studies were carried out to assess the feasibility of using an aqueous slurry, with lithium in its solid component, to meet the tritium breeding, cooling, and shielding requirements of a controlled thermonuclear reactor (CTR). The numerical studies were designed to demonstrate the theoretical ability of a conceptual slurry blanket to breed adequate tritium to sustain the CTR. The experimental studies were designed to show that the tritium retention characteristics of likely solid components for the slurry were conducive to adequate tritium recovery without the need for isotopic separation. The numerical portion of this work consisted in part of using ANISN, a one-dimensional finite difference neutron transport code, to model the neutronic performance of the slurry blanket concept. The parameters governing tritium production and retention in a slurry were computed and used to modify the results of the ANISN computer runs. The numerical work demonstrated that the slurry blanket was only marginally capable of breeding sufficient tritium without the aid of a neutron multiplying region. The experimental portion of this work consisted of several neutron irradiation experiments, which were designed to determine the retention abilities of LiF particles

Tank Farm WM-182 and WM-183 Heel Slurry Samples PSD Results

International Nuclear Information System (INIS)

Batcheller, T.A.; Huestis, G.M.

2000-01-01

Particle size distribution (PSD) analysis of INTEC Tank Farm WM-182 and WM-183 heel slurry samples were performed using a modified Horiba LA-300 PSD analyzer at the RAL facility. There were two types of testing performed: typical PSD analysis, and setting rate testing. Although the heel slurry samples were obtained from two separate vessels, the particle size distribution results were quite similar. The slurry solids were from approximately a minimum particle size of 0.5 mm to a maximum of 230 mm with about 90% of the material between 2-to-133 mm, and the cumulative 50% value at approximately 20 mm. This testing also revealed that high frequency sonication with an ultrasonic element may break-up larger particles in the WM-182 and WM-183 tank from heel slurries. This finding represents useful information regarding ultimate tank heel waste processing. Settling rate testing results were also fairly consistent with material from both vessels in that it appears that most of the mass of solids settle to an agglomerated, yet easily redispersed layer at the bottom. A dispersed and suspended material remained in the ''clear'' layer above the settled layer after about one-half an hour of settling time. This material had a statistical mode of approximately 5 mm and a maximum particle size of 30 mm

Controlling the radiative properties of cool black-color coatings pigmented with CuO submicron particles

International Nuclear Information System (INIS)

Gonome, Hiroki; Baneshi, Mehdi; Okajima, Junnosuke; Komiya, Atsuki; Maruyama, Shigenao

2014-01-01

The objective of this study was to design a pigmented coating with dark appearance that maintains a low temperature while exposed to sunlight. The radiative properties of a black-color coating pigmented with copper oxide (CuO) submicron particles are described. In the present work, the spectral behavior of the CuO-pigmented coating was calculated. The radiative properties of CuO particles were evaluated, and the radiative transfer in the pigmented coating was modeled using the radiation element method by ray emission model (REM 2 ). The coating is made using optimized particles. The reflectivity is measured by spectroscopy and an integrating sphere in the visible (VIS) and near infrared (NIR) regions. By using CuO particles controlled in size, we were able to design a black-color coating with high reflectance in the NIR region. The coating substrate also plays an important role in controlling the reflectance. The NIR reflectance of the coating on a standard white substrate with appropriate coating thickness and volume fraction was much higher than that on a standard black substrate. From the comparison between the experimental and calculated results, we know that more accurate particle size control enables us to achieve better performance. The use of appropriate particles with optimum size, coating thickness and volume fraction on a suitable substrate enables cool and black-color coating against solar irradiation. -- Highlights: • A new approach in designing pigmented coatings was used. • The effects of particles size on both visible and near infrared reflectivities were studied. • The results of numerical calculation were compared with experimental ones for CuO powders

Analysis system of submicron particle tracks in the fine-grained nuclear emulsion by a combination of hard x-ray and optical microscopy

International Nuclear Information System (INIS)

Naka, T.; Asada, T.; Yoshimoto, M.; Katsuragawa, T.; Tawara, Y.; Umemoto, A.; Suzuki, Y.; Terada, Y.; Takeuchi, A.; Uesugi, K.; Kimura, M.

2015-01-01

Analyses of nuclear emulsion detectors that can detect and identify charged particles or radiation as tracks have typically utilized optical microscope systems because the targets have lengths from several μm to more than 1000 μm. For recent new nuclear emulsion detectors that can detect tracks of submicron length or less, the current readout systems are insufficient due to their poor resolution. In this study, we developed a new system and method using an optical microscope system for rough candidate selection and the hard X-ray microscope system at SPring-8 for high-precision analysis with a resolution of better than 70 nm resolution. Furthermore, we demonstrated the analysis of submicron-length tracks with a matching efficiency of more than 99% and position accuracy of better than 5 μm. This system is now running semi-automatically

Advanced computational model for three-phase slurry reactors

International Nuclear Information System (INIS)

Goodarz Ahmadi

2000-11-01

In the first year of the project, solid-fluid mixture flows in ducts and passages at different angle of orientations were analyzed. The model predictions are compared with the experimental data and good agreement was found. Progress was also made in analyzing the gravity chute flows of solid-liquid mixtures. An Eulerian-Lagrangian formulation for analyzing three-phase slurry flows in a bubble column is being developed. The approach uses an Eulerian analysis of gas liquid flows in the bubble column, and makes use of the Lagrangian particle tracking procedure to analyze the particle motions. Progress was also made in developing a rate dependent thermodynamically consistent model for multiphase slurry flows in a state of turbulent motion. The new model includes the effect of phasic interactions and leads to anisotropic effective phasic stress tensors. Progress was also made in measuring concentration and velocity of particles of different sizes near a wall in a duct flow. The formulation of a thermodynamically consistent model for chemically active multiphase solid-fluid flows in a turbulent state of motion was also initiated. The general objective of this project is to provide the needed fundamental understanding of three-phase slurry reactors in Fischer-Tropsch (F-T) liquid fuel synthesis. The other main goal is to develop a computational capability for predicting the transport and processing of three-phase coal slurries. The specific objectives are: (1) To develop a thermodynamically consistent rate-dependent anisotropic model for multiphase slurry flows with and without chemical reaction for application to coal liquefaction. Also to establish the material parameters of the model. (2) To provide experimental data for phasic fluctuation and mean velocities, as well as the solid volume fraction in the shear flow devices. (3) To develop an accurate computational capability incorporating the new rate-dependent and anisotropic model for analyzing reacting and

3D-printed conductive static mixers enable all-vanadium redox flow battery using slurry electrodes

Science.gov (United States)

Percin, Korcan; Rommerskirchen, Alexandra; Sengpiel, Robert; Gendel, Youri; Wessling, Matthias

2018-03-01

State-of-the-art all-vanadium redox flow batteries employ porous carbonaceous materials as electrodes. The battery cells possess non-scalable fixed electrodes inserted into a cell stack. In contrast, a conductive particle network dispersed in the electrolyte, known as slurry electrode, may be beneficial for a scalable redox flow battery. In this work, slurry electrodes are successfully introduced to an all-vanadium redox flow battery. Activated carbon and graphite powder particles are dispersed up to 20 wt% in the vanadium electrolyte and charge-discharge behavior is inspected via polarization studies. Graphite powder slurry is superior over activated carbon with a polarization behavior closer to the standard graphite felt electrodes. 3D-printed conductive static mixers introduced to the slurry channel improve the charge transfer via intensified slurry mixing and increased surface area. Consequently, a significant increase in the coulombic efficiency up to 95% and energy efficiency up to 65% is obtained. Our results show that slurry electrodes supported by conductive static mixers can be competitive to state-of-the-art electrodes yielding an additional degree of freedom in battery design. Research into carbon properties (particle size, internal surface area, pore size distribution) tailored to the electrolyte system and optimization of the mixer geometry may yield even better battery properties.

Electrode geometry effects on the collection efficiency of submicron and ultra-fine dust particles in spike-plate electrostatic precipitators

International Nuclear Information System (INIS)

Brocilo, D; Podlinski, J; Chang, J S; Mizeraczyk, J; Findlay, R D

2008-01-01

The collection efficiency of electrostatic precipitators for the submicron particles ranging from 0.1 to 1 μm and ultrafine particles smaller than 0. lμm is below the requirements of new PM2.5 emission regulations. In this work, numerical and experimental studies were conducted to examine the effect of discharge and collecting electrode geometries on the ion density and electric field profiles and consequently their effect on the particle surface charge and collection efficiency. The collection efficiency prediction was based on a modified Deutsche's equation after calculation of three dimensional electric field and ion density profiles. Whereas, the particle surface charge was obtained from diffusion and field charging models. Results show that the collection efficiency of fine particles for the spike-type discharge electrode when compared to the conventional wire-type was improved. Experimental validations were conducted on a bench scale electrostatic precipitator for total and partial collection efficiency of particles ranging in size from 0.01 to 20 μm and the results indicated that the model can be effectively applied for prototype design, modification, and scale-up of collecting and discharge electrodes.

High temperature oxidation of slurry coated interconnect alloys

DEFF Research Database (Denmark)

Persson, Åsa Helen

with this interaction mechanism mainly give a geometrical protection against oxidation by blocking oxygen access at the surface of the oxide scale. The protecting effect is gradually reduced as the oxide scale grows thicker than the diameter of the coating particles. Interaction mechanism B entails a chemical reaction...... scale. The incorporated coating particles create a geometrical protection against oxidation that should not loose their effect after the oxide scale has grown thicker than the diameter of the coating particles. The two single layer coatings consisting of (La0.85Sr0.15)MnO3 + 10% excess Mn, LSM, and (La0......In this project, high temperature oxidation experiments of slurry coated ferritic alloys in atmospheres similar to the atmosphere found at the cathode in an SOFC were conducted. From the observations possible interaction mechanisms between the slurry coatings and the growing oxide scale...

Enhancement in electrical conductivity of pastes containing submicron Ag-coated Cu filler with palmitic acid surface modification

Science.gov (United States)

Choi, Eun Byeol; Lee, Jong-Hyun

2017-09-01

The fabrication and applied use of submicron Ag-coated Cu (Cu@Ag) particles as a filler material for epoxy-based conductive pastes having the advantages of a lower material cost and antioxidation behavior were studied. Submicron Cu@Ag particles were successfully prepared and surface-modified using palmitic acid. Diffuse reflectance infrared Fourier transform spectroscopy and thermogravimetric differential scanning calorimetry results indicated the formation of an organic layer by the chemical interaction between the Cu@Ag surface and palmitic acid and the survival of the organic layer after treatment at 160 °C for 3 h in air. The printed pastes containing both commercial micron Cu@Ag flakes and the fabricated submicron Cu@Ag particles showed a greatly reduced electrical resistivity (4.68 × 10-4 Ω cm) after surface modification compared to an initial value of 1.85 × 10-3 Ω cm when cured.

Heterogeneous ice slurry flow and concentration distribution in horizontal pipes

International Nuclear Information System (INIS)

Wang, Jihong; Zhang, Tengfei; Wang, Shugang

2013-01-01

Highlights: • A Mixture CFD model is applied to describe heterogeneous ice slurry flow. • The ice slurry rheological behavior is considered piecewise. • The coupled flow and concentration profiles in heterogeneous slurry flow is acquired. • The current numerical model achieves good balance between precision and universality. -- Abstract: Ice slurry is an energy-intensive solid–liquid mixture fluid which may play an important role in various cooling purposes. Knowing detailed flow information is important from the system design point of view. However, the heterogeneous ice slurry flow makes it difficult to be quantified due to the complex two phase flow characteristic. The present study applies a Mixture computational fluid dynamics (CFD) model based on different rheological behavior to characterize the heterogeneous ice slurry flow. The Mixture CFD model was firstly validated by three different experiments. Then the validated Mixture CFD model was applied to solve the ice slurry isothermal flow by considering the rheological behavior piecewise. Finally, the numerical solutions have displayed the coupled flow information, such as slurry velocity, ice particle concentration and pressure drop distribution. The results show that, the ice slurry flow distribution will appear varying degree of asymmetry under different operating conditions. The rheological behavior will be affected by the asymmetric flow distributions. When mean flow velocity is high, Thomas equation can be appropriate for describing ice slurry viscosity. While with the decreasing of mean flow velocity, the ice slurry behaves Bingham rheology. As compared with experimental pressure drop results, the relative errors of numerical computation are almost within ±15%. The Mixture CFD model is validated to be an effective model for describing heterogeneous ice slurry flow and could supply plentiful flow information

ABSORPTION OF GASES INTO ACTIVATED CARBON WATER SLURRIES IN A STIRRED CELL

NARCIS (Netherlands)

TINGE, JT; DRINKENBURG, AAH

A surface-aerated stirred cell with a flat liquid surface was used to investigate the absorption of propane and ethene gas into slurries of activated carbon and water. Slurries with a solids concentration up to 4% by weight and particle diameters up to 565-mu-m were used. The experimental mass

Aerosols generated by spills of viscous solutions and slurries

International Nuclear Information System (INIS)

Ballinger, M.Y.; Hodgson, W.H.

1986-12-01

Safety assessments and environmental impact statements for nuclear fuel cycle facilities require an estimate of potential airborne releases caused by accidents. Aerosols generated by accidents are being investigated by Pacific Northwest Laboratory to develop methods for estimating source terms from these accidents. Experiments were run by spilling viscous solutions and slurries to determine the mass and particle-size distribution of the material made airborne. In all cases, 1 L of solution was spilled from a height of 3 m. Aqueous solutions of sucrose (0 to 56%) gave a range of viscosities from 1.3 to 46 cp. The percent of spill mass made airborne from the spills of these solutions ranged from 0.001 to 0.0001. The mass of particles made airborne decreased as solution viscosity increased. Slurry loading ranged from 25 to 51% total solids. The maximum source airborne (0.0046 wt %) occurred with the slurry that had the lightest loading of soluble solids. The viscosity of the carrying solution also had an impact on the source term from spilling slurries. The effect of surface tension on the source term was examined in two experiments. Surface tension was halved in these spills by adding a surfactant. The maximum weight percent airborne from these spills was 0.0045, compared to 0.003 for spills with twice the surface tension. The aerodynamic mass medium diameters for the aerosols produced by spills of the viscous solutions, slurries, and low surface tension liquids ranged from 0.6 to 8.4 μm, and the geometric standard deviation ranged from 3.8 to 28.0

Slurry burner for mixture of carbonaceous material and water

Science.gov (United States)

Nodd, D.G.; Walker, R.J.

1985-11-05

The present invention is intended to overcome the limitations of the prior art by providing a fuel burner particularly adapted for the combustion of carbonaceous material-water slurries which includes a stationary high pressure tip-emulsion atomizer which directs a uniform fuel into a shearing air flow as the carbonaceous material-water slurry is directed into a combustion chamber, inhibits the collection of unburned fuel upon and within the atomizer, reduces the slurry to a collection of fine particles upon discharge into the combustion chamber, and regulates the operating temperature of the burner as well as primary air flow about the burner and into the combustion chamber for improved combustion efficiency, no atomizer plugging and enhanced flame stability.

Slurry Erosion Studies on Surface Modified 13Cr-4Ni Steels: Effect of Angle of Impingement and Particle Size

Science.gov (United States)

Manisekaran, T.; Kamaraj, M.; Sharrif, S. M.; Joshi, S. V.

2007-10-01

Hydroturbine steels, such as 13Cr-4Ni martensitic steels, are generally subjected to heavy-erosive wear and loss of efficiency due to solid particulate entrainment in the water. Surface-modified steels have proven to give better performance in terms of erosive wear resistance. In the present study, an attempt is made to investigate the effect of angle of impingement and particle size on slurry-jet erosion behavior of pulsed plasma nitrided and laser hardened 13Cr-4Ni steels. Laser hardening process has shown good performance at all angles of impingement due to martensitic transformation of retained austenite. Plastic deformation mode of material removal was also an evident feature of all laser-hardened surface damage locations. However, pulsed-plasma nitrided steels have exhibited chip formation and micro-cutting mode of erosive wear. Erosion with 150-300 μm size was twice compared to 150 μm size slurry particulates.

Implications of the Differential Toxicological Effects of III-V Ionic and Particulate Materials for Hazard Assessment of Semiconductor Slurries.

Science.gov (United States)

Jiang, Wen; Lin, Sijie; Chang, Chong Hyun; Ji, Zhaoxia; Sun, Bingbing; Wang, Xiang; Li, Ruibin; Pon, Nanetta; Xia, Tian; Nel, André E

2015-12-22

Because of tunable band gaps, high carrier mobility, and low-energy consumption rates, III-V materials are attractive for use in semiconductor wafers. However, these wafers require chemical mechanical planarization (CMP) for polishing, which leads to the generation of large quantities of hazardous waste including particulate and ionic III-V debris. Although the toxic effects of micron-sized III-V materials have been studied in vivo, no comprehensive assessment has been undertaken to elucidate the hazardous effects of submicron particulates and released III-V ionic components. Since III-V materials may contribute disproportionately to the hazard of CMP slurries, we obtained GaP, InP, GaAs, and InAs as micron- (0.2-3 μm) and nanoscale (particles for comparative studies of their cytotoxic potential in macrophage (THP-1) and lung epithelial (BEAS-2B) cell lines. We found that nanosized III-V arsenides, including GaAs and InAs, could induce significantly more cytotoxicity over a 24-72 h observation period. In contrast, GaP and InP particulates of all sizes as well as ionic GaCl3 and InCl3 were substantially less hazardous. The principal mechanism of III-V arsenide nanoparticle toxicity is dissolution and shedding of toxic As(III) and, to a lesser extent, As(V) ions. GaAs dissolves in the cell culture medium as well as in acidifying intracellular compartments, while InAs dissolves (more slowly) inside cells. Chelation of released As by 2,3-dimercapto-1-propanesulfonic acid interfered in GaAs toxicity. Collectively, these results demonstrate that III-V arsenides, GaAs and InAs nanoparticles, contribute in a major way to the toxicity of III-V materials that could appear in slurries. This finding is of importance for considering how to deal with the hazard potential of CMP slurries.

Comparison of sources of submicron particle number concentrations measured at two sites in Rochester, NY.

Science.gov (United States)

Kasumba, John; Hopke, Philip K; Chalupa, David C; Utell, Mark J

2009-09-01

Sources contributing to the submicron particles (100-470 nm) measured between January 2002 and December 2007 at two different New York State Department of Environmental Conservation (NYS DEC) sites in Rochester, NY were identified and apportioned using a bilinear receptor model, positive matrix factorization (PMF). Measurements of aerosol size distributions and number concentrations for particles in the size range of 10-500 nm have been made since December 2001 to date in Rochester. The measurements are being made using a scanning mobility particle sizer (SMPS) consisting of a DMA and a CPC (TSI models 3071 and 3010, respectively). From December 2001 to March 2004, particle measurements were made at the NYS DEC site in downtown Rochester, but it was moved to the eastside of Rochester in May 2004. Each measurement period was divided into three seasons i.e., winter (December, January, and February), summer (June, July, and August), and the transitional periods (March, April, May, September, October, and November) so as to avoid experimental uncertainty resulting from too large season-to-season variability in ambient temperature and solar photon intensity that would lead to unstable/non-stationary size distributions. Therefore, the seasons were analyzed independently for possible sources. Ten sources were identified at both sites and these include traffic, nucleation, residential/commercial heating, industrial emissions, secondary nitrate, ozone- rich secondary aerosol, secondary sulfate, regionally transported aerosol, and a mixed source of nucleation and traffic. These results show that the measured total outdoor particle number concentrations in Rochester generally vary with similar temporal patterns, suggesting that the central monitoring site data can be used to estimate outdoor exposure in other parts of the city.

Production of solid lipid submicron particles for protein delivery using a novel supercritical gas-assisted melting atomization process.

Science.gov (United States)

Salmaso, Stefano; Elvassore, Nicola; Bertucco, Alberto; Caliceti, Paolo

2009-02-01

A supercritical carbon dioxide micronization technique based on gas-assisted melting atomization has been designed to prepare protein-loaded solid lipid submicron particles. The supercritical process was applied to homogeneous dispersions of insulin in lipid mixtures: (1) tristearin, Tween-80, phosphatidylcholine and 5 kDa PEG (1:0.1:0.9:1 and 1:0.1:0.9:2 weight ratio); and (2) tristearin, dioctyl sulfosuccinate and phosphatidylcholine (1:1:0.5 weight ratio). Optimized process conditions yielded dry nonagglomerated powders with high product recovery (70%, w/w). Dynamic light scattering and transmission electron microscopy showed that two size fractions of particles, with 80-120 and 200-400 nm diameters, were produced. In all final products, dimethylsulfoxide used to prepare the insulin/lipid mixture was below 20 ppm. Protein encapsulation efficiency increased up to 80% as the DMSO content in the insulin/lipid mixture increased. Compared to the particles without PEG, the polymer-containing particles dispersed rapidly in water, and the dispersions were more stable under centrifugation as less than 20% of suspended particles precipitated after extensive centrifugation. In vitro, the protein was slowly released from the formulation without PEG, while a burst and faster release were obtained from the formulations containing PEG. Subcutaneous injection to diabetic mice of insulin extracted from the particles showed that the supercritical process did not impair the protein hypoglycemic activity.

Airborne studies of submicron aerosol in the troposphere over West Siberia

Energy Technology Data Exchange (ETDEWEB)

Panchenko, M.V.; Zuev, V.E.; Belan, B.D.; Terpugova, S.A. [Institute of Atmospheric Optics, Tomsk (Russian Federation)

1996-04-01

Submicron fraction particles that have the longest lifespan and are included in almost all atmospheric processes are of special importance among the great variety of sizes of particles present in the atmosphere. Submicron particles mainly determine the opticle state of the atmosphere in the visible spectral range, essentially cause the absorption of infrared radiation and, since they are the products and participants in all aerosol-to-gas transformations, accumulate of a lot of various chemical compounds and transfer them to large distances. Investigation of the processes of the spatial-temporal variability of aerosol particles for different climatic zones of the earth is the experimental base for studying their effect on climatically and ecologically significant factors and estimating their unfavorable tendencies. The increasing anthropogenic loading of the earth`s atmosphere is creating an urgency for aerosol research. Regardless of how perfect the analytical and numerical methods of solving radiation problems may be, success in forecasting climatic change is mainly determined by the reliability of the experimental data on optical parameters of the atmosphere and of the description of their variability under the effect of external factors.

Pressure Prediction of Coal Slurry Transportation Pipeline Based on Particle Swarm Optimization Kernel Function Extreme Learning Machine

Directory of Open Access Journals (Sweden)

Xue-cun Yang

2015-01-01

Full Text Available For coal slurry pipeline blockage prediction problem, through the analysis of actual scene, it is determined that the pressure prediction from each measuring point is the premise of pipeline blockage prediction. Kernel function of support vector machine is introduced into extreme learning machine, the parameters are optimized by particle swarm algorithm, and blockage prediction method based on particle swarm optimization kernel function extreme learning machine (PSOKELM is put forward. The actual test data from HuangLing coal gangue power plant are used for simulation experiments and compared with support vector machine prediction model optimized by particle swarm algorithm (PSOSVM and kernel function extreme learning machine prediction model (KELM. The results prove that mean square error (MSE for the prediction model based on PSOKELM is 0.0038 and the correlation coefficient is 0.9955, which is superior to prediction model based on PSOSVM in speed and accuracy and superior to KELM prediction model in accuracy.

An Approach to Understanding Cohesive Slurry Settling, Mobilization, and Hydrogen Gas Retention in Pulsed Jet Mixed Vessels

Energy Technology Data Exchange (ETDEWEB)

Gauglitz, Phillip A.; Wells, Beric E.; Fort, James A.; Meyer, Perry A.

2009-05-22

The Hanford Waste Treatment and Immobilization Plant (WTP) is being designed and built to pretreat and vitrify a large portion of the waste in Hanford’s 177 underground waste storage tanks. Numerous process vessels will hold waste at various stages in the WTP. Some of these vessels have mixing-system requirements to maintain conditions where the accumulation of hydrogen gas stays below acceptable limits, and the mixing within the vessels is sufficient to release hydrogen gas under normal conditions and during off-normal events. Some of the WTP process streams are slurries of solid particles suspended in Newtonian fluids that behave as non-Newtonian slurries, such as Bingham yield-stress fluids. When these slurries are contained in the process vessels, the particles can settle and become progressively more concentrated toward the bottom of the vessels, depending on the effectiveness of the mixing system. One limiting behavior is a settled layer beneath a particle-free liquid layer. The settled layer, or any region with sufficiently high solids concentration, will exhibit non-Newtonian rheology where it is possible for the settled slurry to behave as a soft solid with a yield stress. In this report, these slurries are described as settling cohesive slurries.

Submicron superconducting structures

International Nuclear Information System (INIS)

Golovashkin, A.I.; Lykov, A.N.

1986-01-01

An overview of works concerning superconducting structures of submicron dimensions and a system of such structures is given. It is noted that usage of the above structures in superconducting microelectronics permits, first, to increase the element packing density, to decrease the signal transmission time, capacity, power dissipated in high-frequency applications. Secondly, negligible coherence length in transition metals, their alloys and high-temperature compounds also restrict the dimensions of superconducting weak couplings when the 'classical' Josephson effect is displayed. The most effective methods for production of submicron superconducting structures are the following: lithography, double scribering. Recently the systems of superconducting submicron elements are extensively studied. It is shown that such systems can be phased by magnetic field

Biotreatment of hydrocarbons from petroleum tank bottom sludges in soil slurries

International Nuclear Information System (INIS)

Ferrari, M.D.; Neirotti, E.; Albornoz, C.; Mostazo, M.R.; Cozzo, M.

1996-01-01

Biotreatment of oil wastes in aqueous slurries prepared with sandy loam soil and inoculated with selected soil cultures was evaluated. After 90 days, oil removal was 47%. Removal of each hydrocarbon class was 84% for saturates, 20% for aromatics, and 44% for asphaltenes. Resins increased by 68%. The use of a soil with a lower level of fine particles or minor organic matter content, or reinoculation with fresh culture did not improve oil elimination. Residual oil recovered from slurries was biotreated. Oil removal was 22%. Slurry-phase biotreatment showed less variability and faster oil removal than solid-phase biotreatment. (author)

Studies of coal slurries property; Slurry no seijo ni kansuru kento

Energy Technology Data Exchange (ETDEWEB)

Kawabata, M.; Aihara, Y.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Nogami, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan); Sakaki, T.; Shibata, M.; Hirosue, H. [Kyushu National Industrial Research Institute, Saga (Japan)

1996-10-28

It was previously found that the increase of slurry temperature provides a significant effect of slurry viscosity reduction for the coal slurry with high concentration of 50 wt%. To investigate the detailed influence of slurry temperature for the coal slurry with concentration of 50 wt%, influence of temperature on the successive change of apparent viscosity was observed at the constant shear rate. When the concentration of coal was increased from 45 wt% to 50 wt%, viscosity of the slurry was rapidly increased. When heated above 70{degree}C, the apparent viscosity decreased during heating to the given temperature, but it increased successively after reaching to the given temperature. The apparent viscosity showed higher value than that of the initial viscosity. The coal slurry with concentration of 50 wt% showed the fluidity of Newtonian fluid at the lower shear rate region, but showed the fluidity of pseudo-plastic fluid at the higher shear rate region. The slurry having high apparent viscosity by the successive change showed higher apparent viscosity with increasing the higher even by changing the shear rate. 1 ref., 4 figs.

Efflux Performance of Submicron Particles in Packed Bed under Periodic Pressure Conditions; Shuki atsuho ni yoru juten sonai sabumikuron biryushi no ryushutsu tokusei

Energy Technology Data Exchange (ETDEWEB)

Ping, Z; Iritani, E; Murase, T [Nagaya Univ. Nagoya (Japan). Department of Chemical Engineering

1997-09-01

Permeation experiments of ultrapure water were conducted under periodic pressure conditions using a packed bed obtained by dispersing submicron particles of polymethyl methacrylate (PMMA) uniformly into a packed bed of particles of White Alundum. It is clearly demonstrated that washing performance under periodic pressure conditions where the permeation pressure is applied periodically is improved dramatically, compared with that under constant pressure conditions. It is also shown that the effect of periodic pressure operation is especially noticeable in the initial stage of the pressurizing period, and that a pressurizing time smaller than 2 min is very effective under conditions examined in this study. 4 figs.

The CO{sub 2} hydrate slurry; Le coulis de glace

Energy Technology Data Exchange (ETDEWEB)

Sari, O.; Hu, J.; Eicher, S.; Brun, F. [Institute of Thermal Engineering, University of Applied Sciences of Western Switzerland, Yverdon-les-Bains (Switzerland); Sari, O.; Hu, J. [Clean Cooling Solutions, spin off of University of Applied Sciences of Western Switzerland, Yverdon-les-Bains (Switzerland); Homsy, P. [Nestec Ltd, Vevey (Switzerland); Logel, J.-C. [Axima Refrigeration, Bischheim (France)

2007-12-15

A new, very promising refrigerant was developed, which could be used in industrial processes as well as air conditioners: the CO{sub 2} hydrate slurry. Replacing hydrochlorofluorocarbon HCFC refrigerants has a high priority, due to the strong negative environmental impact of these fluids. New refrigerants have to be environment friendly, non-inflammable, cheap and made of natural materials. CO{sub 2} hydrate slurries and/or a mixture of ice slurry and CO{sub 2} hydrate slurry meet these requirements. The University of Applied Sciences of Western Switzerland in Yverdon, together with industrial partners, investigated the properties of such slurries. The slurries were created using the Coldeco process: the refrigerating fluid is directly injected into the liquid brine. The evaporation of the refrigerating fluid cools the liquid down to its freezing point and homogeneously distributed small crystals appear in the liquid. A test rig was built to measure the physical and chemical properties of the slurries obtained in this way. CO{sub 2} hydrate slurries have a higher energy storage capacitance (500 kJ/kg) than ice slurries (333 kJ/kg). The production of CO{sub 2} hydrate slurries in large quantities in a continuous process was demonstrated. The solid particle concentration was 10%, the pressure amounted to 30 bar and the temperature 2 to 4 {sup o}C. Such slurries can be pumped and circulated in pipe networks. Stainless steel is the appropriate material for such networks. However, the main advantage of the new refrigerant will be, according to the authors, a reduced energy consumption compared to traditional refrigerating cycles: the difference between the temperature required by the user and the refrigerant temperature is reduced, thanks to the use of the latent heat in the new process.

Innovative approach to produce submicron drug particles by vibrational atomization spray drying: influence of the type of solvent and surfactant.

Science.gov (United States)

Durli, T L; Dimer, F A; Fontana, M C; Pohlmann, A R; Beck, R C R; Guterres, S S

2014-08-01

Spray drying is a technique used to produce solid particles from liquid solutions, emulsions or suspensions. Buchi Labortechnik developed the latest generation of spray dryers, Nano Spray Dryer B-90. This study aims to obtain, directly, submicron drug particles from an organic solution, employing this equipment and using dexamethasone as a model drug. In addition, we evaluated the influence of both the type of solvent and surfactant on the properties of the powders using a 3(2) full factorial analysis. The particles were obtained with high yields (above 60%), low water content (below 2%) and high drug content (above 80%). The surface tension and the viscosity were strongly influenced by the type of solvent. The highest powder yields were obtained for the highest surface tension and the lowest viscosity of the drug solutions. The use of ionic surfactants led to higher process yields. The laser diffraction technique revealed that the particles deagglomerate into small ones with submicrometric size, (around 1 µm) that was also observed by scanning electron microscopy. Interaction between the raw materials in the spray-dried powders was verified by calorimetric analysis. Thus, it was possible to obtain dexamethasone submicrometric particles by vibrational atomization from organic solution.

Development of peat-oil (POM) and peat-alcohol (PAM) slurries as alternative fuels

Energy Technology Data Exchange (ETDEWEB)

Clemens, D F

1983-11-01

The preparation and evaluation of peat/No. 2 fuel oil mixtures (POM) and peat/methanol mixtures (PAM) is described. POM and PAM prepared using North Carolina peat and having varied peat loadings, peat moisture contents and peat particle sizes have been studied by measuring slurry sedimentation ratios and drain times from sedimentation tubes. The peat moisture content was particularly crucial in forming stable slurries. The effect of a variety of additives at 0.5-1.0 wt% on sedimentation ratios, drain times and viscosities was studied. Calorimetric studies of several PAM and POM slurries as well as preliminary combustion tests of POM slurries in a salamander burner are also reported.

Improvement in mechanical properties of hypereutectic Al-Si-Cu alloys through sono-solidiifed slurry

Institute of Scientific and Technical Information of China (English)

Yoshiki Tsunekawa; Shinpei Suetsugu; Masahiro Okumiya; Naoki Nishikawa; Yoshikazu Genma

2014-01-01

For the wider applications, it is necessary to improve the ductility as wel as the strength and wear-resistance of hypereutectic Al-Si-Cu aloys, which are typical light-weight wear-resistant materials. An increase in the amounts of primary silicon particles causes the modiifed wear-resistance of hypereutectic Al-Si-Cu aloys, but leads to the poor strength and ductility. It is known that dual phase steels composed of hetero-structure have succeeded in bringing contradictory mechanical properties of high strength and ductility concurrently. In order to apply the idea of hetero-structure to hypereutectic Al-Si-Cu alloys for the achievement of high strength and ductility along with wear resistance, ultrasonic irradiation of the molten metal during the solidiifcation, which is caled sono-solidiifcation, was carried out from its molten state to just above the eutectic temperature. The sono-solidiifed Al-17Si-4Cu aloy is composed of hetero-structure, which are, hard primary silicon particles, soft non-equilibriuma-Al phase and the eutectic region. Rheo-casting was performed at just above the eutectic temperature with sono-solidiifed slurry to shape a disk specimen. After the rheo-casting with modiifed sono-solidiifed slurry held for 45 s at 570 ºC, the quantitative optical microscope observation exhibits that the microstructure is composed of 18area% of hard primary silicon particles and 57area% of softa-Al phase. In contrast, there exist only 5 area% of primary silicon particles and noa-Al phase in rheo-cast specimen with normaly solidiifed slurry. Hence the tensile tests of T6 treated rheo-cast specimens with modified sono-solidified slurry exhibit improved strength and 5% of elongation, regardless of having more than 3 times higher amounts of primary silicon particles compared to that of rheo-cast specimen with normaly solidiifed slurry.

Influence of the shape of soaring particle based on coal-water slurry containing petrochemicals on ignition characteristics

Directory of Open Access Journals (Sweden)

Valiullin Timur R.

2017-01-01

Full Text Available This paper examines the laws of stable ignition of organic coal-water slurry containing petrochemicals (CWSP. The CWSP is based on the filter cake of coal and scavenge oil. The experiments are performed for individual CWSP particles soaring in a special set-up. The temperature and velocity of an oxidizer flow are varied between 500-1200 K, and 0.5-3 m/s. The dimensions (longitudinal and transverse of particles range are from 0.5 mm to 5 mm. The study indicates how the shape of a fuel particle (sphere, ellipsoid, and polyhedron influences its ignition characteristics (delay time, minimum temperature, modes, stages. Based on the experimental results, the paper explains why the surface configuration of particles influences the conditions of heat transfer with an oxidizer. The results obtained for soaring particles are compared with the results for fixed CWSP particles having different surface configurations (sphere, ellipsoid, and polyhedron. In general, the study may contribute to the expansion of the fuel resource base. The experimental data may be used for the development of the technologies of burning CWSP prepared by recycling traditional fuels. As a result of this study, several recommendations for the practical application of research results are made.

A spectrometer for submicron particles

International Nuclear Information System (INIS)

Pourprix, M.

1995-01-01

The electrostatic spectrometer for aerosol particles, is composed of two coaxial parallel conductive disks between which an electric field is established; an annular slot in the first disk allows for the atmosphere air intake. Suction and injection systems, and a third intermediate conductive disk are used to carry out a dynamic confinement that allows for the separation of particles having various electronic mobility and the determination of the suspended particle size distribution. Application to aerosol size spectrum determination and air quality monitoring

Yield Stress Reduction of DWPF Melter Feed Slurries

International Nuclear Information System (INIS)

Stone, M.E.; Smith, M.E.

2007-01-01

, then quenched with a water spray. Approximately 90% of the frit was converted to beads by this process. Yield stress reduction was measured by preparing melter feed slurries (using nonradioactive HLW simulants) that contain beads and comparing the yield stress with melter feed containing frit. A second set of tests was performed with beads of various diameters to determine if a decrease in diameter affected the results. Smaller particle size was shown to increase yield stress when frit is utilized. The settling rate of the beads was required to match the settling rate of the frit, therefore a decrease in particle size was anticipated. Settling tests were conducted in water, xanthan gum solutions, and in non-radioactive simulants of the HLW. The tests used time-lapse video-graphy as well as solids sampling to evaluate the settling characteristics of beads compared to frit of the same particle size. A preliminary melt rate evaluation was performed using a dry-fed Melt Rate Furnace (MRF) developed by SRNL. Preliminary evaluation of the impact of beading the frit on the frit addition system were completed by conducting flow loop testing. A recirculation loop was built with a total length of about 30 feet. Pump power, flow rate, outlet pressure, and observations of the flow in the horizontal upper section of the loop were noted. The recirculation flow was then gradually reduced and the above items recorded until settling was noted in the recirculation line. Overall, the data shows that the line pressure increased as the solids were increased for the same flow rate. In addition, the line pressure was higher for Frit 320 than the beads at the same solids level and flow. With the observations, a determination of minimum velocity to prevent settling could be done, but a graph of the line pressures versus velocity for the various tests was deemed to more objective. The graph shows that the inflection point in pressure drop is about the same for the beads and Frit 320. This

PHYSICAL PROPERTIES OF KAOLIN/SAND SLURRY USED DURING SUBMERSIBLE MIXER PUMP TESTS AT TNX

International Nuclear Information System (INIS)

HANSEN, ERICH

2005-01-01

The purpose of this task is to characterize the physical properties of the kaolin/sand slurries used during the testing of a new submersible mixer pump (SMP) which had undergone performance testing at the TNX Waste Tank mockup facility from July 2004 through May 2005. During this time period, four identical SMPs were subjected to various water tests and four different tests using different batches of kaolin/sand slurries. The physical properties of the kaolin/sand slurries were measured for three of the four tests. In these tests, three different sample locations were used to pull samples, the SMP cooling water exit (CWE), the SMP fluid flow field (FFF), and SMP effective cleaning radius (ECR). The physical properties measured, though not for each sample, included rheology, weight percent total solids (wt% TS), density, kaolin/sand slurry particle size distribution (PSD), weight percent and particles size distribution of material greater than 45 microns

The effect of sintering time on synthesis of in situ submicron {alpha}-Al{sub 2}O{sub 3} particles by the exothermic reactions of CuO particles in molten pure Al

Energy Technology Data Exchange (ETDEWEB)

Dikici, Burak, E-mail: burakdikici@yyu.edu.tr [Yuzuncu Yil University, Department of Mechanical Engineering, 65080 Van (Turkey); Gavgali, Mehmet [Ataturk University, Department of Mechanical Engineering, 25240 Erzurum (Turkey)

2013-02-25

Highlights: Black-Right-Pointing-Pointer Al-Cu/Al{sub 2}O{sub 3} composites were prepared successfully by means of hot pressing method. Black-Right-Pointing-Pointer Sintering time of the Al-CuO system effect the reaction rate and formation of Al{sub 2}O{sub 3}. Black-Right-Pointing-Pointer Increase in sintering time accelerates formation of submicron in situ {alpha}-Al{sub 2}O{sub 3} phase. Black-Right-Pointing-Pointer Hardness of the sintered composite for 30 min at 1000 Degree-Sign C increased from 60 to 174 HV. - Abstract: In this study, in situ {alpha}-Al{sub 2}O{sub 3} reinforcing particles have been successfully synthesised in an Al-Cu matrix alloy by means of the conventional Hot Pressing (HP) method. The effect of sintering time on the forming of the {alpha}-Al{sub 2}O{sub 3} phase at 1000 Degree-Sign C was investigated using Differential Thermal Analysis (DTA), X-ray Diffraction (XRD) and a Scanning Electron Microscope (SEM). The sintered composites contained thermodynamically stable {alpha}-Al{sub 2}O{sub 3} particles and {theta}-Al{sub 2}Cu eutectic phases, which were embedded in the Al-Cu matrix. The in situ {alpha}-Al{sub 2}O{sub 3} particles were generally spherical and their mean size was observed to be less than 0.5 {mu}m. The results showed that sintering time influences not only the reaction rate of copper and the formation of Al{sub 2}O{sub 3}. Also, an increase in the sintering time accelerates the formation of submicron in situ {alpha}-Al{sub 2}O{sub 3} particles and decreases the quantity of {theta}-Al{sub 2}Cu intermetallic phase in the liquid aluminium. Additionally, sintering of composite for 30 min at 1000 Degree-Sign C increased the hardness from 60 to 174 HV.

Modified two-step emulsion solvent evaporation technique for fabricating biodegradable rod-shaped particles in the submicron size range.

Science.gov (United States)

Safari, Hanieh; Adili, Reheman; Holinstat, Michael; Eniola-Adefeso, Omolola

2018-05-15

Though the emulsion solvent evaporation (ESE) technique has been previously modified to produce rod-shaped particles, it cannot generate small-sized rods for drug delivery applications due to the inherent coupling and contradicting requirements for the formation versus stretching of droplets. The separation of the droplet formation from the stretching step should enable the creation of submicron droplets that are then stretched in the second stage by manipulation of the system viscosity along with the surface-active molecule and oil-phase solvent. A two-step ESE protocol is evaluated where oil droplets are formed at low viscosity followed by a step increase in the aqueous phase viscosity to stretch droplets. Different surface-active molecules and oil phase solvents were evaluated to optimize the yield of biodegradable PLGA rods. Rods were assessed for drug loading via an imaging agent and vascular-targeted delivery application via blood flow adhesion assays. The two-step ESE method generated PLGA rods with major and minor axis down to 3.2 µm and 700 nm, respectively. Chloroform and sodium metaphosphate was the optimal solvent and surface-active molecule, respectively, for submicron rod fabrication. Rods demonstrated faster release of Nile Red compared to spheres and successfully targeted an inflamed endothelium under shear flow in vitro and in vivo. Copyright © 2018 Elsevier Inc. All rights reserved.

Effects of submicron ammonium sulfate particles on the growth and yield of komatsuna (Brassica rapa L. var. perviridis)

Science.gov (United States)

Motai, Akira; Nakaba, Satoshi; Lenggoro, I. Wuled; Watanabe, Makoto; Wada, Yoshiharu; Izuta, Takeshi

2017-11-01

The aim of this study was to determine the effects of submicron ammonium sulfate (AS) particles on komatsuna (Brassica rapa L. cv. Hakkei) plants. First, we optimized a leaf-washing method to measure the amount of AS particles deposited on the leaf surface of the plants. Then, we used this method to determine the retention time of particles deposited on the leaf surface of the plants. We also investigated the effects of AS particles on the growth and yield of the plants. Almost all the AS particles deposited on the leaf surface were removed within 1 min washing time with ultrapure water, and ion leaching from the leaf was relatively slow but continuous during the leaf-washing procedure. On the basis of these results, we determined that 1 min was a suitable washing time to remove most of the AS particles while minimizing the influence of ion leaching from the leaf. The amount of particulate SO42- deposited on the leaf surface decreased over time, probably because AS particles deposited on the leaf surface deliquesced, allowing ions such as SO42- in the deliquescence solution to be absorbed into the leaf. The plants were grown and exposed to AS particles for 16 days in naturally lit phytotrons. The daily mean increase in the concentration of SO42- in PM2.5 by the exposure to AS particles was 22.5 μg m-3 in the phytotrons. The growth and yield of the plants were significantly reduced by the exposure to AS particles. The exposure to AS particles did not affect the leaf concentrations of nitrogen and chlorophyll, but significantly reduced stomatal conductance. Therefore, stomatal closure is one of the reasons for the AS particle-induced reductions in the growth and yield of komatsuna plants.

Synthesis and characterization of monodisperse, mesoporous, and magnetic sub-micron particles doped with a near-infrared fluorescent dye

International Nuclear Information System (INIS)

Le Guevel, Xavier; Nooney, Robert; McDonagh, Colette; MacCraith, Brian D.

2011-01-01

Recently, multifunctional silica nanoparticles have been investigated extensively for their potential use in biomedical applications. We have prepared sub-micron monodisperse and stable multifunctional mesoporous silica particles with a high level of magnetization and fluorescence in the near infrared region using an one-pot synthesis technique. Commercial magnetite nanocrystals and a conjugated-NIR-dye were incorporated inside the particles during the silica condensation reaction. The particles were then coated with polyethyleneglycol to stop aggregation. X-ray diffraction, N 2 adsorption analysis, TEM, fluorescence and absorbance measurements were used to structurally characterize the particles. These mesoporous silica spheres have a large surface area (1978 m 2 /g) with 3.40 nm pore diameter and a high fluorescence in the near infrared region at λ=700 nm. To explore the potential of these particles for drug delivery applications, the pore accessibility to hydrophobic drugs was simulated by successfully trapping a hydrophobic ruthenium dye complex inside the particle with an estimated concentration of 3 wt%. Fluorescence imaging confirmed the presence of both NIR dye and the post-grafted ruthenium dye complex inside the particles. These particles moved at approximately 150 μm/s under the influence of a magnetic field, hence demonstrating the multifunctionality and potential for biomedical applications in targeting and imaging. - Graphical Abstract: Hydrophobic fluorescent Ruthenium complex has been loaded into the mesopores as a surrogate drug to simulate drug delivery and to enhance the multifunctionality of the magnetic NIR emitting particles. Highlights: → Monodisperse magnetic mesoporous silica particles emitting in the near infrared region are obtained in one-pot synthesis. → We prove the capacity of such particles to uptake hydrophobic dye to mimic drug loading. → Loaded fluorescent particles can be moved under a magnetic field in a microfluidic

An investigation on characterizing dense coal-water slurry with ultrasound: theoretical and experimental method

Energy Technology Data Exchange (ETDEWEB)

Xue, M.H.; Su, M.X.; Dong, L.L.; Shang, Z.T.; Cai, X.S. [Shanghai University of Science & Technology, Shanghai (China)

2010-07-01

Particle size distribution and concentration in particulate two-phase flow are important parameters in a wide variety of industrial areas. For the purpose of online characterization in dense coal-water slurries, ultrasonic methods have many advantages such as avoiding dilution, the capability for being used in real time, and noninvasive testing, while light-based techniques are not capable of providing information because optical methods often require the slurry to be diluted. In this article, the modified Urick equation including temperature modification, which can be used to determine the concentration by means of the measurement of ultrasonic velocity in a coal-water slurry, is evaluated on the basis of theoretical analysis and experimental study. A combination of the coupled-phase model and the Bouguer-Lambert-Beer law is employed in this work, and the attenuation spectrum is measured within the frequency region from 3 to 12 MHz. Particle size distributions of the coal-water slurry at different volume fractions are obtained with the optimum regularization technique. Therefore, the ultrasonic technique presented in this work brings the possibility of using ultrasound for online measurements of dense slurries.

Physical Characterization of Solid-Liquid Slurries at High Weight Fractions Using Optical and Ultrasonic Methods

International Nuclear Information System (INIS)

Burgess, L.W.; Brodsky, A.M.; Panetta P.D.

2005-01-01

Remediation of highly radioactive waste is a major technical and programmatic challenge for the DOE. Rapid, on-line physical characterization of highly concentrated slurries is required for the safe and efficient remediation of 90 million gallons of high level radioactive waste (HLW), sodium bearing waste, and mixed waste. The research presented here, describes a collaborative effort between Pacific Northwest National Laboratory (PNNL) and the University of Washington (UW) to directly address the need for rapid on-line characterization of the physical properties of HLW slurries during all phases of the remediation process, from in-tank characterization of sediments to monitoring of the concentration, particle size, and degree of agglomeration and gelation of slurries during transport. Near-surface characterization of the slurry flow in the particle size range from nanometer to micrometer is examined using optical low coherence reflectometry. Volumetric characterization at depths in the slurry flow, up to several centimeters in the particle size range from the micrometer to millimeter, is realized by utilizing ultrasonic backscatter and diffuses fields. One of the strengths, the teaming up of significant talents in both experimental and theoretical optics and in ultrasonics, provides a synergistic approach to integrate these complimentary techniques. One of the benefits of this combined approach is the physical characterization of HLW over a concentration and particle size range that is broader than can be achieved with today's technology. This will avoid a costly increase in waste stream volume due to excess dilution, and will lessen chance of plugging pipes that could shut down expensive processing lines

Submicron and nano formulations of titanium dioxide and zinc oxide stimulate unique cellular toxicological responses in the green microalga Chlamydomonas reinhardtii

Energy Technology Data Exchange (ETDEWEB)

Gunawan, Cindy, E-mail: c.gunawan@unsw.edu.au [ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering, The University of New South Wales, Sydney, NSW (Australia); Sirimanoonphan, Aunchisa [ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering, The University of New South Wales, Sydney, NSW (Australia); Teoh, Wey Yang [Clean Energy and Nanotechnology (CLEAN) Laboratory, School of Energy and Environment, City University of Hong Kong, Kowloon, Hong Kong Special Administrative Region (Hong Kong); Marquis, Christopher P., E-mail: c.marquis@unsw.edu.au [School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW (Australia); Amal, Rose [ARC Centre of Excellence for Functional Nanomaterials, School of Chemical Engineering, The University of New South Wales, Sydney, NSW (Australia)

2013-09-15

Highlights: • Uptake of TiO{sub 2} solids by C. reinhardtii generates ROS as an early stress response. • Submicron and nanoTiO{sub 2} exhibit benign effect on cell proliferation. • Uptake of ZnO solids and leached zinc by C. reinhardtii inhibit the alga growth. • No cellular oxidative stress is detected with submicron and nano ZnO exposure. • The toxicity of particles is not necessarily mediated by cellular oxidative stress. -- Abstract: The work investigates the eco-cytoxicity of submicron and nano TiO{sub 2} and ZnO, arising from the unique interactions of freshwater microalga Chlamydomonas reinhardtii to soluble and undissolved components of the metal oxides. In a freshwater medium, submicron and nano TiO{sub 2} exist as suspended aggregates with no-observable leaching. Submicron and nano ZnO undergo comparable concentration-dependent fractional leaching, and exist as dissolved zinc and aggregates of undissolved ZnO. Cellular internalisation of solid TiO{sub 2} stimulates cellular ROS generation as an early stress response. The cellular redox imbalance was observed for both submicron and nano TiO{sub 2} exposure, despite exhibiting benign effects on the alga proliferation (8-day EC50 > 100 mg TiO{sub 2}/L). Parallel exposure of C. reinhardtii to submicron and nano ZnO saw cellular uptake of both the leached zinc and solid ZnO and resulting in inhibition of the alga growth (8-day EC50 ≥ 0.01 mg ZnO/L). Despite the sensitivity, no zinc-induced cellular ROS generation was detected, even at 100 mg ZnO/L exposure. Taken together, the observations confront the generally accepted paradigm of cellular oxidative stress-mediated cytotoxicity of particles. The knowledge of speciation of particles and the corresponding stimulation of unique cellular responses and cytotoxicity is vital for assessment of the environmental implications of these materials.

Submicron and nano formulations of titanium dioxide and zinc oxide stimulate unique cellular toxicological responses in the green microalga Chlamydomonas reinhardtii

International Nuclear Information System (INIS)

Gunawan, Cindy; Sirimanoonphan, Aunchisa; Teoh, Wey Yang; Marquis, Christopher P.; Amal, Rose

2013-01-01

Highlights: • Uptake of TiO 2 solids by C. reinhardtii generates ROS as an early stress response. • Submicron and nanoTiO 2 exhibit benign effect on cell proliferation. • Uptake of ZnO solids and leached zinc by C. reinhardtii inhibit the alga growth. • No cellular oxidative stress is detected with submicron and nano ZnO exposure. • The toxicity of particles is not necessarily mediated by cellular oxidative stress. -- Abstract: The work investigates the eco-cytoxicity of submicron and nano TiO 2 and ZnO, arising from the unique interactions of freshwater microalga Chlamydomonas reinhardtii to soluble and undissolved components of the metal oxides. In a freshwater medium, submicron and nano TiO 2 exist as suspended aggregates with no-observable leaching. Submicron and nano ZnO undergo comparable concentration-dependent fractional leaching, and exist as dissolved zinc and aggregates of undissolved ZnO. Cellular internalisation of solid TiO 2 stimulates cellular ROS generation as an early stress response. The cellular redox imbalance was observed for both submicron and nano TiO 2 exposure, despite exhibiting benign effects on the alga proliferation (8-day EC50 > 100 mg TiO 2 /L). Parallel exposure of C. reinhardtii to submicron and nano ZnO saw cellular uptake of both the leached zinc and solid ZnO and resulting in inhibition of the alga growth (8-day EC50 ≥ 0.01 mg ZnO/L). Despite the sensitivity, no zinc-induced cellular ROS generation was detected, even at 100 mg ZnO/L exposure. Taken together, the observations confront the generally accepted paradigm of cellular oxidative stress-mediated cytotoxicity of particles. The knowledge of speciation of particles and the corresponding stimulation of unique cellular responses and cytotoxicity is vital for assessment of the environmental implications of these materials

COMPUTATIONAL AND EXPERIMENTAL MODELING OF THREE-PHASE SLURRY-BUBBLE COLUMN REACTOR

Energy Technology Data Exchange (ETDEWEB)

Isaac K. Gamwo; Dimitri Gidaspow

1999-09-01

Considerable progress has been achieved in understanding three-phase reactors from the point of view of kinetic theory. In a paper in press for publication in Chemical Engineering Science (Wu and Gidaspow, 1999) we have obtained a complete numerical solution of bubble column reactors. In view of the complexity of the simulation a better understanding of the processes using simplified analytical solutions is required. Such analytical solutions are presented in the attached paper, Large Scale Oscillations or Gravity Waves in Risers and Bubbling Beds. This paper presents analytical solutions for bubbling frequencies and standing wave flow patterns. The flow patterns in operating slurry bubble column reactors are not optimum. They involve upflow in the center and downflow at the walls. It may be possible to control flow patterns by proper redistribution of heat exchangers in slurry bubble column reactors. We also believe that the catalyst size in operating slurry bubble column reactors is not optimum. To obtain an optimum size we are following up on the observation of George Cody of Exxon who reported a maximum granular temperature (random particle kinetic energy) for a particle size of 90 microns. The attached paper, Turbulence of Particles in a CFB and Slurry Bubble Columns Using Kinetic Theory, supports George Cody's observations. However, our explanation for the existence of the maximum in granular temperature differs from that proposed by George Cody. Further computer simulations and experiments involving measurements of granular temperature are needed to obtain a sound theoretical explanation for the possible existence of an optimum catalyst size.

The development of peat-oil (POM) and peat-alcohol (PAM) slurries as alternative fuels

Energy Technology Data Exchange (ETDEWEB)

Clemens, D F; Evans, G O; Harrell, P A; Whitehurst, B M

1983-11-01

The preparation and evaluation of peat/No. 2 fuel oil mixtures (POM) and peat/methanol mixtures (PAM) is described. POM and PAM prepared using North Carolina peat and having varied peat loadings, peat moisture contents, and peat particle sizes have been studied by measuring slurry sedimentation ratios and drain times from sedimentation tubes. The peat moisture content was particularly crucial in forming stable slurries. The effect of a variety of additives at 0.5-1.0 wt.% on sedimentation ratios, drain times, and viscosities was studied. Calorimetric studies of several PAM and POM slurries as well as preliminary combustion tests of POM slurries in a salamander burner are also reported.

Comments to "Analysis of constant rate period of spray drying of slurry" by Liang et al., 2001

DEFF Research Database (Denmark)

Jørgensen, Kåre; Jensen, Anker Degn; Sloth, Jakob

2006-01-01

In the study by Liang et al. [2001. Analysis of constant rate period of spray drying of slurry. Chemical Engineering Science 56, 2205-2213] the Darcy flow of liquid through a pore system of primary particles to the surface of a slurry droplet was applied for the constant rate period. Steep primary...... particle concentration gradients inside -25 mu m droplets with a primary particle size of 0.2 mu m were observed. Unfortunately, the boundary condition at the droplet surface for the parabolic second-order PDE did not conserve the solid mass in the droplet, and the plots for the primary particle...

Submicron X-ray diffraction

International Nuclear Information System (INIS)

MacDowell, Alastair; Celestre, Richard; Tamura, Nobumichi; Spolenak, Ralph; Valek, Bryan; Brown, Walter; Bravman, John; Padmore, Howard; Batterman, Boris; Patel, Jamshed

2000-01-01

At the Advanced Light Source in Berkeley the authors have instrumented a beam line that is devoted exclusively to x-ray micro diffraction problems. By micro diffraction they mean those classes of problems in Physics and Materials Science that require x-ray beam sizes in the sub-micron range. The instrument is for instance, capable of probing a sub-micron size volume inside micron sized aluminum metal grains buried under a silicon dioxide insulating layer. The resulting Laue pattern is collected on a large area CCD detector and automatically indexed to yield the grain orientation and deviatoric (distortional) strain tensor of this sub-micron volume. A four-crystal monochromator is then inserted into the beam, which allows monochromatic light to illuminate the same part of the sample. Measurement of diffracted photon energy allows for the determination of d spacings. The combination of white and monochromatic beam measurements allow for the determination of the total strain/stress tensor (6 components) inside each sub-micron sized illuminated volume of the sample

Using artificial fluorescent particles as tracers of livestock wastes within an agricultural catchment

International Nuclear Information System (INIS)

Granger, Steve J.; Bol, Roland; Hawkins, Jane M.B.; White, Sue M.; Naden, Pamela S.; Old, Gareth H.; Marsh, Jon K.; Bilotta, Gary S.; Brazier, Richard E.; Macleod, Christopher J.A.; Haygarth, Philip M.

2011-01-01

Evidence for the movement of agricultural slurry and associated pollutants into surface waters is often anecdotal, particularly with relation to its 'particulate' components which receive less attention than 'bio-available' soluble phases. To assess the extent of movement of slurry particles artificial fluorescent particles were mixed with slurry and applied to a field sub-catchment within a headwater catchment. Particles were 2-60 μm in diameter and two different densities, 2.7 and 1.2 g cm -3 representing 'inorganic' and 'organic' material. Water samples from the field and catchment outlet were collected during two storm events following slurry application and analysed for particle and suspended sediment concentrations (SSC). SSC from the field and catchment outlet always formed clockwise hysteresis loops indicating sediment exhaustion and particles of the two densities were always found to be positively correlated. Particles from the field formed clockwise hysteresis loops during the first discharge event after slurry application, but anti-clockwise hysteresis loops during the second monitored event which indicated a depletion of readily mobilisable particles. Particles from the catchment outlet always formed anticlockwise hysteresis loops. Particle size became finer spatially, between field and catchment outlet, and temporally, between successive storm events. The results indicate that slurry particles may be readily transported within catchments but that different areas may contribute to pollutant loads long after the main peak in SSC has passed. The density of the particles did not appear to have any effect on particle transport however the size of the particles may play a more important role in the 2-60 μm range. - Research Highlights: → This study traces the movement of agricultural slurry particles from land to waters. → Two densities of artificial fluorescent particles were applied to a nested catchment. → Slurry particles moved from point of

The differences between soil grouting with cement slurry and cement-water glass slurry

Science.gov (United States)

Zhu, Mingting; Sui, Haitong; Yang, Honglu

2018-01-01

Cement slurry and cement-water glass slurry are the most widely applied for soil grouting reinforcement project. The viscosity change of cement slurry is negligible during grouting period and presumed to be time-independent while the viscosity of cement-water glass slurry increases with time quickly and is presumed to be time-dependent. Due to the significantly rheology differences between them, the grouting quality and the increasing characteristics of grouting parameters may be different, such as grouting pressure, grouting surrounding rock pressure, i.e., the change of surrounding rock pressure deduced by grouting pressure. Those are main factors for grouting design. In this paper, a large-scale 3D grouting simulation device was developed to simulate the surrounding curtain grouting for a tunnel. Two series of surrounding curtain grouting experiments under different geo-stress of 100 kPa, 150 kPa and 200 kPa were performed. The overload test on tunnel was performed to evaluate grouting effect of all surrounding curtain grouting experiments. In the present results, before 240 seconds, the grouting pressure increases slowly for both slurries; after 240 seconds the increase rate of grouting pressure for cement-water glass slurry increases quickly while that for cement slurry remains roughly constant. The increasing trend of grouting pressure for cement-water glass is similar to its viscosity. The setting time of cement-water glass slurry obtained from laboratory test is less than that in practical grouting where grout slurry solidifies in soil. The grouting effect of cement-water glass slurry is better than that of cement slurry and the grouting quality decreases with initial pressure.

Advanced computational model for three-phase slurry reactors

International Nuclear Information System (INIS)

Goodarz Ahmadi

2001-10-01

In the second year of the project, the Eulerian-Lagrangian formulation for analyzing three-phase slurry flows in a bubble column is further developed. The approach uses an Eulerian analysis of liquid flows in the bubble column, and makes use of the Lagrangian trajectory analysis for the bubbles and particle motions. An experimental set for studying a two-dimensional bubble column is also developed. The operation of the bubble column is being tested and diagnostic methodology for quantitative measurements is being developed. An Eulerian computational model for the flow condition in the two-dimensional bubble column is also being developed. The liquid and bubble motions are being analyzed and the results are being compared with the experimental setup. Solid-fluid mixture flows in ducts and passages at different angle of orientations were analyzed. The model predictions were compared with the experimental data and good agreement was found. Gravity chute flows of solid-liquid mixtures is also being studied. Further progress was also made in developing a thermodynamically consistent model for multiphase slurry flows with and without chemical reaction in a state of turbulent motion. The balance laws are obtained and the constitutive laws are being developed. Progress was also made in measuring concentration and velocity of particles of different sizes near a wall in a duct flow. The technique of Phase-Doppler anemometry was used in these studies. The general objective of this project is to provide the needed fundamental understanding of three-phase slurry reactors in Fischer-Tropsch (F-T) liquid fuel synthesis. The other main goal is to develop a computational capability for predicting the transport and processing of three-phase coal slurries. The specific objectives are: (1) To develop a thermodynamically consistent rate-dependent anisotropic model for multiphase slurry flows with and without chemical reaction for application to coal liquefaction. Also establish the

Natural convection heat transfer enhancement using Microencapsulated Phase-Change-Material slurries

International Nuclear Information System (INIS)

Kubo, Shinji; Akino, Norio; Tanaka, Amane; Nakano, Fumihiko; Nagashima, Akira.

1997-01-01

The present study investigates natural convection heat transfer from a heated cylinder cooled by a water slurry of Microencapsulated Phase Change Material (MCPCM). A normal paraffin hydrocarbon with carbon number of 18 and melting point of 27.9degC, is microencapsulated by Melamine resin into particles of which average diameter is 9.5μm and specific weight is same as water. The slurry of the MCPCM and water is put into a test apparatus, which is a rectangular enclosure with a heated horizontal cylinder. As the concentrations of PCM in the slurry are changed in 1,3 and 5%, the heat transfer coefficients of the cylinder are larger than that of water as working fluid, by 3,20 and 35% enhancements respectively. (author)

Debris flow rheology: Experimental analysis of fine-grained slurries

Science.gov (United States)

Major, Jon J.; Pierson, Thomas C.

1992-01-01

The rheology of slurries consisting of ≤2-mm sediment from a natural debris flow deposit was measured using a wide-gap concentric-cylinder viscometer. The influence of sediment concentration and size and distribution of grains on the bulk rheological behavior of the slurries was evaluated at concentrations ranging from 0.44 to 0.66. The slurries exhibit diverse rheological behavior. At shear rates above 5 s−1 the behavior approaches that of a Bingham material; below 5 s−1, sand exerts more influence and slurry behavior deviates from the Bingham idealization. Sand grain interactions dominate the mechanical behavior when sand concentration exceeds 0.2; transient fluctuations in measured torque, time-dependent decay of torque, and hysteresis effects are observed. Grain rubbing, interlocking, and collision cause changes in packing density, particle distribution, grain orientation, and formation and destruction of grain clusters, which may explain the observed behavior. Yield strength and plastic viscosity exhibit order-of-magnitude variation when sediment concentration changes as little as 2–4%. Owing to these complexities, it is unlikely that debris flows can be characterized by a single rheological model.

Physical Characterization of Solid-Liquid Slurries at High Weight Fractions Using Optical and Ultrasonic Methods. Final Report

International Nuclear Information System (INIS)

Burgess, Lloyd W.

2009-01-01

Remediation of highly radioactive waste is a major technical and programmatic challenge for the DOE. Rapid, on-line physical characterization of highly concentrated slurries is required for the safe and efficient remediation of 90 million gallons of high level radioactive waste (HLW), sodium bearing waste, and mixed waste. The research presented here, describes a collaborative effort between Pacific Northwest National Laboratory (PNNL) and the University of Washington to directly address the need for rapid on-line characterization of the physical properties of HLW slurries during all phases of the remediation process, from in-tank characterization of sediments to monitoring of the concentration, particle size, and degree of agglomeration and gelation of slurries during transport. Near-surface characterization of the slurry flow in the particle size range from nanometer to micrometer is examined using optical low coherence reflectometry. Volumetric characterization at depths in the slurry flow, up to several centimeters in the particle size range from the micrometer to millimeter, is realized by utilizing ultrasonic backscatter and diffuses fields. One of the strengths, the teaming up of significant talents in both experimental and theoretical optics (University of Washington) and in ultrasonics (Pacific Northwest National Laboratory (PNNL)) provides a synergistic approach to integrate these complimentary techniques. One of the benefits of this combined approach is the physical characterization of HLW over a concentration and particle size range that is broader than can be achieved with today's technology. This will avoid a costly increase in waste stream volume due to excess dilution, and will lessen chance of plugging pipes that could shut down expensive processing lines.

Waste Slurry Particle Properties for Use in Slurry Flow Modeling

Energy Technology Data Exchange (ETDEWEB)

Jewett, J. R.; Conrads, T. J.; Julyk, L. J.; Reynolds, D. A.; Jensen, L.; Kirch, N. W.; Estey, S. D.; Bechtold, D. B.; Callaway III, W. S.; Cooke, G. A.; Herting, D. L.; Person, J. C.; Duncan, J. B.; Onishi, Y.; Tingey, J. M.

2003-02-26

Hanford's tank farm piping system must be substantially modified to deliver high-level wastes from the underground storage tanks to the Waste Treatment Plant now under construction. Improved knowledge of the physical properties of the solids was required to support the design of the modified system. To provide this additional knowledge, particle size distributions for composite samples from seven high-level waste feed tanks were measured using two different laser lightscattering particle size analyzers. These measurements were made under a variety of instrumental conditions, including various flow rates through the sample loop, various stirring rates in the sample reservoir, and before and after subjecting the particles to ultrasonic energy. A mean value over all the tanks of 4.2 {micro}m was obtained for the volume-based median particle size. Additional particle size information was obtained from sieving tests, settling tests and microscopic observations.

Structure, thermal and mechanical properties of in situ Al-based metal matrix composite reinforced with Al2O3 and TiC submicron particles

International Nuclear Information System (INIS)

Yu Peng; Mei Zhi; Tjong, S.C.

2005-01-01

We report herein the structure and characterization of in situ Al-based metal matrix composites (MMCs) prepared from the Al-10 wt.% TiO 2 and Al-10 wt.% TiO 2 -1.5 wt.% C systems via hot isostatic pressing (HIP) at 1000 deg C and 100 MPa. The structure, morphology and thermal behavior of HIPed samples were studied by means of the X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The results indicated that fined Al 2 O 3 particles and large intermetallic Al 3 Ti plates were in situ formed in the Al-10 wt.% TiO 2 sample during HIPing. However, the introduction of C to the Al-TiO 2 system was beneficial to eliminate large intermetallic Al 3 Ti plates. In this case, Al 2 O 3 and TiC submicron particles were in situ formed in the Al-10 wt.% TiO 2 -1.5 wt.% C sample. Three-point-bending test showed that the strength and the strain-at-break of the HIPed Al-10 wt.% TiO 2 -1.5 wt.% C sample were significantly higher than those of its Al-10 wt.% TiO 2 counterpart. The improvement was derived from the elimination of bulk Al 3 Ti intermetallic plates and from the formation of TiC submicron particles. DSC measurements and thermodynamic analyses were carried out to reveal the reaction formation mechanisms of in situ reinforcing phases. The DSC results generally correlated well with the theoretical predictions. Finally, the correlation between the structure-property relationships of in situ composites is discussed

Acoustic Monitor for Liquid-Solid Slurries Measurements at Low Weight Fractions

International Nuclear Information System (INIS)

Tavlarides, L. L.; Sangani, A.; Shcherbakov, A.; Lee, J. S.; Dievendorf, E.

2003-01-01

The principal objective of the project is to develop an acoustic probe for determining the weight fraction of particles in a flowing suspension. The suspension can be solid-liquid (S-L) or solid-gas-liquid (S-G-L). The work will include testing the theory of acoustic wave propagation in suspensions and demonstrating the application of the probe by installing it on a flow loop through which a suspension is flowing and determining the particle weight fraction. The signal from the probe must be processed such that the noise arising from the presence of gas bubbles is removed to yield an accurate estimate of the particle weight fraction. Particular attention will be given to testing suspensions with low particle weight fractions since slurries to be transported in nuclear waste processing will have low particle weight fractions. Originally, the probe was to be developed and tested at Syracuse University (SU) then installed and tested at Oak Ridge National Laboratories (ORNL) for surrogate slurries from the Hanford Nuclear site. However, after discussions between SU and ORNL in June 2002 it was agreed that all tests would be conducted at SU

Acoustic Monitor for Liquid-Solid Slurries Measurements at Low Weight Fractions

International Nuclear Information System (INIS)

Tavlarides, L. L.; Sangani, A.; Shcherbakov, A.; Lee, J. S.; Dievendorf, E.

2002-01-01

The principal objective of the project is to develop an acoustic probe for determining the weight fraction of particles in a flowing suspension. The suspension can be solid-liquid (S-L) or solid-gas-liquid (S-G-L). The work will include testing the theory of acoustic wave propagation in suspensions and demonstrating the application of the probe by installing it on a flow loop through which a suspension is flowing and determining the particle weight fraction. The signal from the probe must be processed such that the noise arising from the presence of gas bubbles is removed to yield an accurate estimate of the particle weight fraction. Particular attention will be given to testing suspensions with low particle weight fractions since slurries to be transported in nuclear waste processing will have low particle weight fractions. Originally, the probe was to be developed and tested at Syracuse University (SU) then installed and tested at Oak Ridge National Laboratories (ORNL) for surrogate slurries from the Hanford Nuclear site. However, after discussions between SU and ORNL in June 2002 it was agreed that all tests would be conducted at SU

Efficient filtration system for paraffin-catalyst slurry separation

Directory of Open Access Journals (Sweden)

Khodagholi Mohammad Ali

2013-01-01

Full Text Available The filtration efficiency for separating liquid paraffin (or water from a slurry consisting of 25 weight% spherical alumina in a Slurry Bubble Column Reactor (SBCR comprised of a cylindrical tube of 10 cm diameter and 150 cm length was studied. Various differential pressures (ΔP were applied to two separate tubular sintered metal stainless steel filter elements with nominal pore size of 4 and 16μm. The experimental results disclosed that the rate of filtrations increased on applying higher differential pressure to the filter element. Albeit this phenomenon is limited to moderate ΔPs and for ΔP more than 1 bar is neither harmful nor helpful. The highest filtration rates at ΔPs higher than 1 bar were 170 and 248 ml/minute for 4 and 16μm respectively. Using water as the liquid in slurry the rate of filtration enhanced to 4 folds, and this issue reveals impact of viscosity on filtration efficiency clearly. In all situations, the total amount of particles present in the filtrate part never exceeded a few parts per million (ppm. The statistical analysis of the SEM image of the filtrate indicated that by applying higher pressure difference to the filter element the frequency percent of larger particle size increases. The operation of filter cake removing was performed with back flashing of 300 ml of clean liquid with pressures of 3-5 bar of N2 gas.

Heterogeneous condensation for submicronic particles abatement

OpenAIRE

Tammaro, Marco

2010-01-01

It is now well established that the emission of sub-micrometric particulate matter entrained in flue gases of industry and vehicles exhausts, is one of the most critical treats for human health because of the toxicological effects of ultrafine particles on the respiratory system and their ability to cross alveoli’s membranes reaching the circulatory system too. Albeit this scenario, the traditional particle abatement devices are mainly designed and optimised to treat particles larger tha...

Toxic assessment of urban atmospheric particle-bound PAHs: Relevance of composition and particle size in Barcelona (Spain)

International Nuclear Information System (INIS)

Mesquita, Sofia Raquel; Drooge, Barend L. van; Reche, Cristina; Guimarães, Laura; Grimalt, Joan O.; Barata, Carlos; Piña, Benjamin

2014-01-01

Zebrafish embryotoxicity and dioxin-like activity levels were tested for particulate air samples from an urban background site in Barcelona (Spain). Samples were collected during 14 months, and maximal values for both biological activities corresponded to samples collected during late autumn months, correlating with elevated PAH levels. Vehicle and combustion emissions appeared as the potentially most toxic sources, whereas total PM mass and mineral content appeared to be poor predictors of the biological activity of the samples. Samples simultaneously collected at different particle size cut-offs (10, 2.5, and 1 μm) did not differ significantly in dioxin-like PAH levels and biological activity, indicating that the sub-micron particle fraction (PM 1 ) concentrated essentially all observed toxicity. Our results support the need for a tighter control on sub-micron particle emissions and show that total PM mass and, particularly, PM 10 , may not fully characterize the toxic potential of air samples. Highlights: • Dioxin-like activity was found in all air particle samples collected in Barcelona. • 50% of the samples showed different levels of fish embryotoxicity. • Toxic effects associated to PAHs and linked to vehicle and combustion emissions. • The toxicity was not correlated to PM mass or mineral content. • The sub-micron particle fraction PM 1 concentrated essentially all observed toxicity. -- In vivo toxic effects associated to sub-micron urban air particles from combustion and vehicle emissions

Slurry erosion induced surface nanocrystallization of bulk metallic glass

Science.gov (United States)

Ji, Xiulin; Wu, Jili; Pi, Jinghong; Cheng, Jiangbo; Shan, Yiping; Zhang, Yingtao

2018-05-01

Microstructure evolution and phase transformation of metallic glasses (MGs) could occur under heating condition or mechanical deformation. The cross-section of as-cast Zr55Cu30Ni5Al10 MG rod was impacted by the solid particles when subjected to erosion in slurry flow. The surface microstructure was observed by XRD before and after slurry erosion. And the stress-driven de-vitrification increases with the increase of erosion time. A microstructure evolution layer with 1-2 μm thickness was formed on the topmost eroded surface. And a short range atomic ordering prevails in the microstructure evolution layer with crystalline size around 2-3 nm embedded in the amorphous matrix. The XPS analysis reveals that most of the metal elements in the MG surface, except for Cu, were oxidized. And a composite layer with ZrO2 and Al2O3 phases were formed in the topmost surface after slurry erosion. The cooling rate during solidification of MG has a strong influence on the slurry erosion induced nanocrystallization. And a lower cooling rate favors the surface nanocrystallization because of lower activation energy and thermo-stability. Finally, the slurry erosion induced surface nanocrystallization and microstructure evolution result in surface hardening and strengthening. Moreover, the microstructure evolution mechanisms were discussed and it is related to the cooling rate of solidification and the impact-induced temperature rise, as well as the combined effects of the impact-induced plastic flow, inter-diffusion and oxidation of the metal elements.

Experimental studies of direct contact heat transfer in a slurry bubble column at high gas temperature of a helium–water–alumina system

International Nuclear Information System (INIS)

Abdulrahman, M.W.

2015-01-01

In this paper, the direct contact heat transfer is investigated experimentally for a helium gas at 90 °C injected through a slurry of water at 22 °C and alumina solid particles in a slurry bubble column reactor. This work examines the effects of superficial gas velocity, static liquid height, solid particles concentration and solid particle size, on the volumetric heat transfer coefficient and slurry temperature of the slurry bubble column reactor. These effects are formulated in forms of empirical equations. From the experimental work, it is found that the volumetric heat transfer coefficient and the slurry temperature increase by increasing the superficial gas velocity with a higher rate of increase at lower superficial gas velocity. In addition, the volumetric heat transfer coefficient and the slurry temperature decrease by increasing the static liquid height and/or the solid concentration at any given superficial gas velocity. Furthermore, it is found that the rate of decrease of the volumetric heat transfer coefficient with the solid concentration is approximately the same for different superficial gas velocities, and the decrease of the slurry temperature with the solid concentration is negligible. - Highlights: • Direct contact heat transfer is investigated experimentally in a slurry bubble column. • Empirical equation of direct contact heat transfer Nusselt number is formulated. • The volumetric heat transfer coefficient increases with superficial gas velocity. • The volumetric heat transfer coefficient decreases with the static liquid height. • The volumetric heat transfer coefficient decreases with the solid concentration.

Submicron-sized aerosol and radon progeny measurements in an uranium mine

International Nuclear Information System (INIS)

Boulaud, D.; Chouard, J.C.

1992-01-01

Submicron-sized aerosol was studied in an uranium mine using an Electrical Aerosol Analyzer and a Differential Mobility Particle Sizer. In addition radon progeny particle size distributions were measured using a prototype instrument developed by us (SDI 2000). With cascade impactor the number weighted mean electrical mobility diameters and the geometric standard deviations ranged respectively from 0.05 to 0.1 μm and 1.8 to 2. The gross alpha activity weighted mean thermodynamic diameters ranged typically from 0.1 to 0.2 μm. 6 refs., 3 figs

Laser direct writing using submicron-diameter fibers.

Science.gov (United States)

Tian, Feng; Yang, Guoguang; Bai, Jian; Xu, Jianfeng; Hou, Changlun; Liang, Yiyong; Wang, Kaiwei

2009-10-26

In this paper, a novel direct writing technique using submicron-diameter fibers is presented. The submicron-diameter fiber probe serves as a tightly confined point source and it adopts micro touch mode in the process of writing. The energy distribution of direct writing model is analyzed by Three-Dimension Finite-Difference Time-Domain method. Experiments demonstrate that submicron-diameter fiber direct writing has some advantages: simple process, 350-nm-resolution (lower than 442-nm-wavelength), large writing area, and controllable width of lines. In addition, by altering writing direction of lines, complex submicron patterns can be fabricated.

Conductivity and electrochemical performance of LiFePO4 slurry in the lithium slurry battery

Science.gov (United States)

Feng, Caimei; Chen, Yongchong; Liu, Dandan; Zhang, Ping

2017-06-01

Lithium slurry battery is a new type of energy storage technique which uses the slurry of solid active materials, conductive additions and liquid electrolyte as the electrode. The proportion of conductive addition and the active material has significant influence on the conductivity and electrochemical performance of the slurry electrode. In the present work, slurries with different volume ratios of LiFePO4 (LFP) and Ketjenblack (KB) were investigated by the electrochemical workstation and charge-discharge testing system (vs. Li/Li+). Results show that the conductivity of the slurry increases linearly with the addition of KB, and the measured specific capacity of the slurry reaches its theoretical value when the volume ratio of KB to LFP is around 0.2. Based on this ratio, a slurry battery with higher loading of LFP (19.1 wt.% in the slurry) was tested, and a specific capacity of 165 mAh/g at 0.2 mA/cm2 and 102 mAh/g at 5 mA/cm2 was obtained for LFP.

System and method for slurry handling

Science.gov (United States)

Steele, Raymond Douglas; Oppenheim, Judith Pauline

2015-12-29

A system includes a slurry depressurizing system that includes a liquid expansion system configured to continuously receive a slurry at a first pressure and continuously discharge the slurry at a second pressure. For example, the slurry depressurizing system may include an expansion turbine to expand the slurry from the first pressure to the second pressure.

Pretreatment methods to obtain pumpable high solid loading wood–water slurries for continuous hydrothermal liquefaction systems

DEFF Research Database (Denmark)

Dãrãbana, Iulia-Maria; Rosendahl, Lasse Aistrup; Pedersen, Thomas Helmer

2015-01-01

Feedstock pretreatment is a prerequisite step for continuous processing of lignocellulosic biomass through HTL, in order to facilitate the pumpability of biomass aqueous slurries. Until now, HTL feedstock pumpability could only be achieved at solid mass content below 15%. In this work, two...... pretreatment methods to obtain wood-based slurries with more than 20% solid mass content, for continuous processing in HTL systems, are proposed. The effect of biomass particle size and pretreatment method on the feedstock pumpability is analyzed. The experimental results show that pumpable wood-based slurries...

Performance Study of Graphite Anode Slurry in Lithium-ion Flow Battery by Ball Milling

Directory of Open Access Journals (Sweden)

FENG Cai-mei

2018-02-01

Full Text Available Graphite anode slurry of lithium-ion flow battery was prepared by the method of ball milling. The morphology, conductivity, specific capacity and cycle performance of graphite anode slurry were studied. Results show that the addition of conductive carbon material can improve the suspension stability of the electrode slurry; the ball milling process can not only improve the suspension stability but also reduce the resistivity of the mixed powders of graphite and conductive carbon materials, the ball milling effect is satisfactory when the mass ratio of the balls and the solid particles is 5:1, but too high ratio of the milling ball and the solid materials can destroy the layer structure of the graphite and affect the stability of the slurry. Increasing the fraction of the graphite and conductive carbon materials can form stable electrical network structure in the slurry and improve the reversible capacity; at the premise of keeping the flowability of the electrode slurry, the reversible specific capacity can be more than 40mAh/g. The capacity loss of graphite anode slurry mainly occurs in the first charging-discharging process, as the increase of the cycles, the capacity loss rate decreases, the capacity goes stable after 5 cycles.

Long-term Chemical Characterization of Submicron Aerosol Particles in the Amazon Forest - ATTO Station

Science.gov (United States)

Carbone, S.; Brito, J.; Rizzo, L. V.; Holanda, B. A.; Cirino, G. G.; Saturno, J.; Krüger, M. L.; Pöhlker, C.; Ng, N. L.; Xu, L.; Andreae, M. O.; Artaxo, P.

2015-12-01

The study of the chemical composition of aerosol particles in the Amazon forest represents a step forward to understand the strong coupling between the atmosphere and the forest. For this reason submicron aerosol particles were investigated in the Amazon forest, where biogenic and anthropogenic aerosol particles coexist at the different seasons (wet/dry). The measurements were performed at the ATTO station, which is located about 150 km northeast of Manaus. At ATTO station the Aerosol chemical speciation monitor (ACSM, Aerodyne) and the Multiangle absorption photometer (MAAP, Thermo 5012) have been operated continuously from March 2014 to July 2015. In this study, long-term measurements (near-real-time, ~30 minutes) of PM1 chemical composition were investigated for the first time in this environment.The wet season presented lower concentrations than the dry season (~5 times). In terms of chemical composition, both seasons were dominated by organics (75 and 63%) followed by sulfate (11 and 13%). Nitrate presented different ratio values between the mass-to-charges 30 to 46 (main nitrate fragments) suggesting the presence of nitrate as inorganic and organic nitrate during both seasons. The results indicated that about 75% of the nitrate signal was from organic nitrate during the dry season. In addition, several episodes with elevated amount of chloride, likely in the form of sea-salt from the Atlantic Ocean, were observed during the wet season. During those episodes, chloride comprised up to 7% of the PM1. During the dry season, chloride was also observed; however, with different volatility, which suggested that Chloride was present in different form and source. Moreover, the constant presence of sulfate and BC during the wet season might be related to biomass burning emissions from Africa. BC concentration was 2.5 times higher during the dry season. Further characterization of the organic fraction was accomplished with the positive matrix factorization (PMF), which

Research on numerical simulation and protection of transient process in long-distance slurry transportation pipelines

International Nuclear Information System (INIS)

Lan, G; Jiang, J; Li, D D; Yi, W S; Zhao, Z; Nie, L N

2013-01-01

The calculation of water-hammer pressure phenomenon of single-phase liquid is already more mature for a pipeline of uniform characteristics, but less research has addressed the calculation of slurry water hammer pressure in complex pipelines with slurry flows carrying solid particles. In this paper, based on the developments of slurry pipelines at home and abroad, the fundamental principle and method of numerical simulation of transient processes are presented, and several boundary conditions are given. Through the numerical simulation and analysis of transient processes of a practical engineering of long-distance slurry transportation pipeline system, effective protection measures and operating suggestions are presented. A model for calculating the water impact of solid and fluid phases is established based on a practical engineering of long-distance slurry pipeline transportation system. After performing a numerical simulation of the transient process, analyzing and comparing the results, effective protection measures and operating advice are recommended, which has guiding significance to the design and operating management of practical engineering of longdistance slurry pipeline transportation system

Research on numerical simulation and protection of transient process in long-distance slurry transportation pipelines

Science.gov (United States)

Lan, G.; Jiang, J.; Li, D. D.; Yi, W. S.; Zhao, Z.; Nie, L. N.

2013-12-01

The calculation of water-hammer pressure phenomenon of single-phase liquid is already more mature for a pipeline of uniform characteristics, but less research has addressed the calculation of slurry water hammer pressure in complex pipelines with slurry flows carrying solid particles. In this paper, based on the developments of slurry pipelines at home and abroad, the fundamental principle and method of numerical simulation of transient processes are presented, and several boundary conditions are given. Through the numerical simulation and analysis of transient processes of a practical engineering of long-distance slurry transportation pipeline system, effective protection measures and operating suggestions are presented. A model for calculating the water impact of solid and fluid phases is established based on a practical engineering of long-distance slurry pipeline transportation system. After performing a numerical simulation of the transient process, analyzing and comparing the results, effective protection measures and operating advice are recommended, which has guiding significance to the design and operating management of practical engineering of longdistance slurry pipeline transportation system.

Study on the effects of temperature, time and policy of pre polymerization on particle morphology in propylene slurry polymerization with heterogeneous ziegler-Natta catalysts

International Nuclear Information System (INIS)

Pircheraghi, G.; Pourmahdian, S.; Vatankhah, M.

2008-01-01

The effects of temperature, time and the strategy of pre polymerization were studied on the morphology of polypropylene particles. Propylene polymerization was carried out in slurry phase using fourth generation of Ziegler-Natta Catalyst, cyclohexylmethyl dimethoxysilane as external electron donor, and triethyl aluminum as co-catalyst. Pre polymerizations were carried out based on two strategies: isothermal and non-isothermal conditions. Particle imaging using SEM, bulk density, and particle size distribution was used to analyse the particle morphology. It was found that the variation of initial condition together with the change in the mechanism of particle fracture has a dominant effect on particle morphology. Each combination between the temperature and reaction time causes to have a special effect on the product particle morphology. It has become clear that in isothermal pre polymerization, spherical particles with identical properties were produced. In low temperature experiments particles with porous surface were observed. At increasing temperature, however, the pores disappeared. Non-isothermal pre polymerization produced different morphological types. In all experiments core shell structures were observed that seemed to be related to the structure of catalysts

Aerosol and NOx emission factors and submicron particle number size distributions in two road tunnels with different traffic regimes

Directory of Open Access Journals (Sweden)

D. Imhof

2006-01-01

Full Text Available Measurements of aerosol particle number size distributions (18–700 nm, mass concentrations (PM2.5 and PM10 and NOx were performed in the Plabutsch tunnel, Austria, and in the Kingsway tunnel, United Kingdom. These two tunnels show different characteristics regarding the roadway gradient, the composition of the vehicle fleet and the traffic frequency. The submicron particle size distributions contained a soot mode in the diameter range D=80–100 nm and a nucleation mode in the range of D=20–40 nm. In the Kingsway tunnel with a significantly lower particle number and volume concentration level than in the Plabutsch tunnel, a clear diurnal variation of nucleation and soot mode particles correlated to the traffic density was observed. In the Plabutsch tunnel, soot mode particles also revealed a diurnal variation, whereas no substantial variation was found for the nucleation mode particles. During the night a higher number concentration of nucleation mode particles were measured than soot mode particles and vice versa during the day. In this tunnel with very high soot emissions during daytime due to the heavy-duty vehicle (HDV share of 18% and another 40% of diesel driven light-duty vehicles (LDV semivolatile species condense on the pre-existing soot surface area rather than forming new particles by homogeneous nucleation. With the low concentration of soot mode particles in the Kingsway tunnel, also the nucleation mode particles exhibit a diurnal variation. From the measured parameters real-world traffic emission factors were estimated for the whole vehicle fleet as well as differentiated into the two categories LDV and HDV. In the particle size range D=18–700 nm, each vehicle of the mixed fleet emits (1.50±0.08×1014 particles km-1 (Plabutsch and (1.26±0.10×1014 particles km-1 (Kingsway, while particle volume emission factors of 0.209±0.008 cm3 km-1 and 0.036±0.004 cm3 km-1, respectively, were obtained. PM1 emission factors of 104±4 mg

Oxygenated organic functional groups and their sources in single and submicron organic particles in MILAGRO 2006 campaign

Directory of Open Access Journals (Sweden)

S. Liu

2009-09-01

Full Text Available Fourier Transform Infrared (FTIR and X-ray Fluorescence (XRF were used to measure organic functional groups and elements of submicron particles collected during MILAGRO in March 2006 on three platforms: the Mexico City urban area (SIMAT, the high altitude site at 4010 m (Altzomoni, and the NCAR C130 aircraft. Scanning Transmission X-ray Microscopy (STXM and Near-Edge X-ray Absorption Fine Structure (NEXAFS were applied to single particle organic functional group abundance analysis of particles simultaneously collected at SIMAT and C130. Correlations of elemental concentrations showed different groups of source-related elements at SIMAT, Altzomoni, and C130, suggesting different processes affecting the air masses sampled at the three platforms. Cluster analysis resulted in seven distinct clusters of FTIR spectra, with the last three clusters consisting of spectra collected almost exclusively on the C130 platform, reflecting the variety of sources contributing to C130 samples. Positive Matrix Factorization (PMF of STXM-NEXAFS spectra identified three main factors representing soot, secondary, and biomass burning type spectra. PMF of FTIR spectra resulted in two fossil fuel combustion factors and one biomass burning factor, the former representative of source regions to the northeast and southwest of SIMAT. Alkane, carboxylic acid, amine, and alcohol functional groups were mainly associated with combustion related sources, while non-acid carbonyl groups were likely from biomass burning events. The majority of OM and O/C was attributed to combustion sources, although no distinction between direct emissions and atmospherically processed OM could be identified.

Characterisation of sub-micron particle number concentrations and formation events in the western Bushveld Igneous Complex, South Africa

Directory of Open Access Journals (Sweden)

A. Hirsikko

2012-05-01

Full Text Available South Africa holds significant mineral resources, with a substantial fraction of these reserves occurring and being processed in a large geological structure termed the Bushveld Igneous Complex (BIC. The area is also highly populated by informal, semi-formal and formal residential developments. However, knowledge of air quality and research related to the atmosphere is still very limited in the area. In order to investigate the characteristics and processes affecting sub-micron particle number concentrations and formation events, air ion and aerosol particle size distributions and number concentrations, together with meteorological parameters, trace gases and particulate matter (PM were measured for over two years at Marikana in the heart of the western BIC. The observations showed that trace gas (i.e. SO₂, NO_x, CO and black carbon concentrations were relatively high, but in general within the limits of local air quality standards. The area was characterised by very high condensation sink due to background aerosol particles, PM₁₀ and O₃ concentration. The results indicated that high amounts of Aitken and accumulation mode particles originated from domestic burning for heating and cooking in the morning and evening, while during daytime SO₂-based nucleation followed by the growth by condensation of vapours from industrial, residential and natural sources was the most probable source for large number concentrations of nucleation and Aitken mode particles. Nucleation event day frequency was extremely high, i.e. 86% of the analysed days, which to the knowledge of the authors is the highest frequency ever reported. The air mass back trajectory and wind direction analyses showed that the secondary particle formation was influenced both by local and regional pollution and vapour sources. Therefore, our observation of the annual cycle and magnitude of the particle formation and growth rates during

Electrochemistry of carbonaceous materials. 3. Reactivity of redox couples with coal slurries in 85% phosphoric acid media

Energy Technology Data Exchange (ETDEWEB)

Tomat, R.; Salmaso, R.; Zecchin, S. [CNR - Istituto di Polarografia ed Elettrochimica Preparativa, Padova (Italy)

1994-02-01

Sardinian subbituminous coal slurries were oxidized in 85% H{sub 3}PO{sub 4} by metal ions (Ce{sup 4+}, V{sup 5+}, V{sup 4+}, Mn{sup 3+} and Fe{sup 3+}) and the effects of metal ion concentration, coal content of slurry, coal particle size and temperature were examined. 19 refs., 3 figs., 2 tabs.

Origin of high oxide to nitride polishing selectivity of ceria-based slurry in the presence of picolinic acid

Institute of Scientific and Technical Information of China (English)

Wang Liang-Yong; Liu Bo; Song Zhi-Tang; Liu Wei-Li; Feng Song-Lin; David Huang; S.V Babu

2011-01-01

We report on the investigation of the origin of high oxide to nitride polishing selectivity of ceria-based slurry in the presence of picolinic acid. The oxide to nitride removal selectivity of the ceria slurry with picolinic acid is as high as 76.6 in the chemical mechanical polishing. By using zeta potential analyzer, particle size analyzer, horizon profilometer, thermogravimetric analysis and Fourier transform infrared spectroscopy, the pre-and the post-polished wafer surfaces as well as the pre-and the post-used ceria-based slurries are compared. Possible mechanism of high oxide to nitride selectivity with using ceria-based slurry with picolinic acid is discussed.

Comparison and analysis of organic components of biogas slurry from eichhornia crassipes solms and corn straw biogas slurry

Science.gov (United States)

Li, Q.; Li, Y. B.; Liu, Z. H.; Min, J.; Cui, Y.; Gao, X. H.

2017-11-01

Biogas slurry is one of anaerobic fermentations, and biomass fermentation biogas slurries with different compositions are different. This paper mainly presents through the anaerobic fermentation of Eichhornia crassipes solms biogas slurry and biogas slurry of corn straw, the organic components of two kinds of biogas slurry after extraction were compared by TLC, HPLC and spectrophotometric determination of nucleic acid and protein of two kinds of biogas slurry organic components, and analyzes the result of comparison.

CFD simulation and experimental analysis of erosion in a slurry tank test rig

Directory of Open Access Journals (Sweden)

Bart Hans-Jörg

2013-04-01

Full Text Available Erosion occurring in equipment dealing with liquid-solid mixtures such as pipeline parts, slurry pumps, liquid-solid stirred reactors and slurry mixers in various industrial applications results in operational failure and economic costs. A slurry erosion tank test rig is designed and was built to investigate the erosion rates of materials and the influencing parameters such as flow velocity and turbulence, flow angle, solid particle concentration, particles size distribution, hardness and target material properties on the material loss and erosion profiles. In the present study, a computational fluid dynamics (CFD tool is used to simulate the erosion rate of sample plates in the liquid-solid slurry mixture in a cylindrical tank. The predictions were made in a steady state and also transient manner, applying the flow at the room temperature and using water and sand as liquid and solid phases, respectively. The multiple reference frame method (MRF is applied to simulate the flow behavior and liquid-solid interactions in the slurry tank test rig. The MRF method is used since it is less demanding than sliding mesh method (SM and gives satisfactory results. The computational domain is divided into three regions: a rotational or MRF zone containing the mixer, a rotational zone (MRF containing the erosion plates and a static zone (outer liquid zone. It is observed that changing the MRF zone diameter and height causes a very low impact on the results. The simulated results were obtained for two kinds of hard metals namely stainless steel and ST-50 under some various operating conditions and are found in good agreement with the experimental results.

The effects of a spray slurry nozzle on copper CMP for reduction in slurry consumption

Energy Technology Data Exchange (ETDEWEB)

Lee, Da Sol; Jeong, Hae Do [Pusan National University, Busan (Korea, Republic of); Lee, Hyun Seop [Tongmyong University, Busan (Korea, Republic of)

2015-12-15

The environmental impact of semiconductor manufacturing has been a big social problem, like greenhouse gas emission. Chemical mechanical planarization (CMP), a wet process which consumes chemical slurries, seriously impacts environmental sustain ability and cost-effectiveness. This paper demonstrates the superiority of a full-cone spray slurry nozzle to the conventional tube-type slurry nozzle in Cu CMP. It was observed that the spray nozzle made a weak slurry wave at the retaining ring unlike a conventional nozzle, because the slurry was supplied uniformly in broader areas. Experiments were implemented with different slurry flow rates and spray nozzle heights. Spray nozzle performance is controlled by the spray angle and spray height. The process temperature was obtained with an infrared (IR) sensor and an IR thermal imaging camera to investigate the cooling effect of the spray. The results show that the spray nozzle provides a higher Material removal rate (MRR), lower non-uniformity (NU), and lower temperature than the conventional nozzle. Computational fluid dynamics techniques show that the turbulence kinetic energy and slurry velocity of the spray nozzle are much higher than those of the conventional nozzle. Finally, it can be summarized that the spray nozzle plays a significant role in slurry efficiency by theory of Minimum quantity lubrication (MQL).

The effects of a spray slurry nozzle on copper CMP for reduction in slurry consumption

International Nuclear Information System (INIS)

Lee, Da Sol; Jeong, Hae Do; Lee, Hyun Seop

2015-01-01

The environmental impact of semiconductor manufacturing has been a big social problem, like greenhouse gas emission. Chemical mechanical planarization (CMP), a wet process which consumes chemical slurries, seriously impacts environmental sustain ability and cost-effectiveness. This paper demonstrates the superiority of a full-cone spray slurry nozzle to the conventional tube-type slurry nozzle in Cu CMP. It was observed that the spray nozzle made a weak slurry wave at the retaining ring unlike a conventional nozzle, because the slurry was supplied uniformly in broader areas. Experiments were implemented with different slurry flow rates and spray nozzle heights. Spray nozzle performance is controlled by the spray angle and spray height. The process temperature was obtained with an infrared (IR) sensor and an IR thermal imaging camera to investigate the cooling effect of the spray. The results show that the spray nozzle provides a higher Material removal rate (MRR), lower non-uniformity (NU), and lower temperature than the conventional nozzle. Computational fluid dynamics techniques show that the turbulence kinetic energy and slurry velocity of the spray nozzle are much higher than those of the conventional nozzle. Finally, it can be summarized that the spray nozzle plays a significant role in slurry efficiency by theory of Minimum quantity lubrication (MQL).

Slurry discharge management-beach profile prediction

Energy Technology Data Exchange (ETDEWEB)

Bravo, R.; Nawrot, J.R. [Southern Illinois University at Carbondale, Carbondale, IL (United States). Dept. of Civil Engineering

1996-11-01

Mine tailings dams are embankments used by the mining industry to retain the tailings products after the mineral preparation process. Based on the acid-waste stereotype that all coal slurry is acid producing, current reclamation requires a four foot soil cover for inactive slurry disposal areas. Compliance with this requirement is both difficult and costly and in some case unnecessary, as not all the slurry, or portions of slurry impoundments are acid producing. Reduced costs and recent popularity of wetland development has prompted many operators to request reclamation variances for slurry impoundments. Waiting to address slurry reclamation until after the impoundment is full, limits the flexibility of reclamation opportunities. This paper outlines a general methodology to predict the formation of the beach profile for mine tailings dams, by the discharge volume and location of the slurry into the impoundment. The review is presented under the perspective of geotechnical engineering and waste disposal management emphasizing the importance of pre-planning slurry disposal land reclamation. 4 refs., 5 figs.

SEPARATION OF FISCHER-TROPSCH WAX PRODUCTS FROM ULTRAFINE IRON CATALYST PARTICLES

Energy Technology Data Exchange (ETDEWEB)

James K. Neathery; Gary Jacobs; Burtron H. Davis

2004-03-31

In this reporting period, a fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of production since the reaction is highly exothermic. Consequently, heavy wax products must be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase FTS. The separation problem is further compounded by catalyst particle attrition and the formation of ultra-fine iron carbide and/or carbon particles. Existing pilot-scale equipment was modified to include a filtration test apparatus. After undergoing an extensive plant shakedown period, filtration tests with cross-flow filter modules using simulant FTS wax slurry were conducted. The focus of these early tests was to find adequate mixtures of polyethylene wax to simulate FTS wax. Catalyst particle size analysis techniques were also developed. Initial analyses of the slurry and filter permeate particles will be used by the research team to design improved filter media and cleaning strategies.

Rheology of tetraphenylborate precipitate slurry

International Nuclear Information System (INIS)

Goren, I.D.; Martin, H.D.; McLain, M.A.

1985-01-01

The rheological properties of tetraphenylborate precipitate slurry were determined. This nonradioactive slurry simulates the radioactive tetraphenylborate precipitate generated at the Savannah River Plant by the In-Tank Precipitation Process. The data obtained in this study was applied in the design of slurry pumps, transfer pumps, transfer lines, and vessel agitation for the Defense Waste Processing Facility and other High Level Waste treatment projects. The precipitate slurry behaves as a Bingham plastic. The yield stress is directly proportional to the concentration of insoluble solids over the range of concentrations studied. The consistency is also a linear function of insoluble solids over the same concentration range. Neither the yield stress nor the consistency was observed to be affected by the presence of the soluble solids. Temperature effects on flow properties of the slurry were also examined: the yield stress is inversely proportional to temperature, but the consistency of the slurry is independent of temperature. No significant time-dependent effects were found. 4 refs., 4 figs., 3 tabs

Hydrodynamic models for slurry bubble column reactors

Energy Technology Data Exchange (ETDEWEB)

Gidaspow, D. [IIT Center, Chicago, IL (United States)

1995-12-31

The objective of this investigation is to convert a {open_quotes}learning gas-solid-liquid{close_quotes} fluidization model into a predictive design model. This model is capable of predicting local gas, liquid and solids hold-ups and the basic flow regimes: the uniform bubbling, the industrially practical churn-turbulent (bubble coalescence) and the slugging regimes. Current reactor models incorrectly assume that the gas and the particle hold-ups (volume fractions) are uniform in the reactor. They must be given in terms of empirical correlations determined under conditions that radically differ from reactor operation. In the proposed hydrodynamic approach these hold-ups are computed from separate phase momentum balances. Furthermore, the kinetic theory approach computes the high slurry viscosities from collisions of the catalyst particles. Thus particle rheology is not an input into the model.

Investigation of the efect of the coal particle sizes on the interfacial and rheological properties of coal-water slurry fuels

Energy Technology Data Exchange (ETDEWEB)

Kihm, K.D.; Deignan, P. [Texas A& M Univ., College Station, TX (United States)

1995-11-01

Experiments were conducted to investigate the effect of particle size on coal-water slurry (CWS) surface tension properties. Two different coal powder samples of different size ranges were obtained through sieving of coal from the Upper Elkhorn Seam. The surfactant (anionic DDBS-soft, dodecylbenzene sulfonic acid) concentration varied from 0 to 1.0% in weight while the coal loading remained at 40% in weight for all the cases. A du Nouy ring tensiometer and a maximum bubble pressure tensiometer measured the static and dynamic surface tensions, respectively, The results show that both static and dynamic surface tensions tend to increase with decreasing coal particle sizes suspended in CWS fuels. Examination of the peak pressure, minimum pressure, surfactant diffusion time, and dead time were also made to correlate these microscopic pressure behavior with the macroscopic dynamic surface tension and to examine the accuracy of the experiment.

Microencapsulated PCM slurry for heat transfer media. 4. Reduction of undercooling

International Nuclear Information System (INIS)

Akino, Norio; Nakano, Fumihiko; Kubo, Shinji; Nagashima, Akira; Sagiya, Syojiro; Nakanishi, Masayuki.

1997-01-01

New heat transfer media with large heat capacity is under development, using a slurry of microencapsulated-phase-change-material (MCPCM) mixed into carrying liquid. To prepare stable MCPCM slurry, fatty acid is selected as PCM owing to relatively large density, and diameter of MCPCM particles are below 10 μm. The temperature difference between melting and freezing points, the so-called undercooling becomes remarkable. To reduce the undercooling, an additive is mixed into fatty acid to introduce nucleation cites. It is concluded that Hexatriacontane is effective to remove undercooling of microencapsulated Lauric acid, Myristic acid and their mixture, and Sebacic acid is effective for Lauric acid. (author)

Method of stripping solid particles

International Nuclear Information System (INIS)

1980-01-01

A method of stripping loaded solid particles is specified in which uniform batches of the loaded particles are passed successively upwardly through an elution column in the form of discrete plugs, the particles of which do not intermingle substantially with the particles of the vertically adjacent plug(s), and are contacted therein with eluant liquid flowed downwardly, strong eluate being withdrawn from the lower region of the column, the loaded particles being supplied as a slurry in a carrier liquid, and successive batches of loaded particles being isolated as measured batches and being separated from their carrier liquid before being contacted with strong eluate and slurried with the strong eluate into the lower region of the column. An example describes the stripping of ion exchange resin particles loaded with complex uranium ions. (author)

Erosion Evaluation of a Slurry Mixer Tank with Computational Fluid Dynamics Methods

International Nuclear Information System (INIS)

Lee, S

2006-01-01

This paper discusses the use of computational fluid dynamics (CFD) methods to understand and characterize erosion of the floor and internal structures in the slurry mixing vessels in the Defense Waste Processing Facility. An initial literature survey helped identify the principal drivers of erosion for a solids laden fluid: the solids content of the working fluid, the regions of recirculation and particle impact with the walls, and the regions of high wall shear. A series of CFD analyses was performed to characterize slurry-flow profiles, wall shear, and particle impingement distributions in key components such as coil restraints and the vessel floor. The calculations showed that the primary locations of high erosion resulting from abrasion were at the leading edge of the coil guide, the tank floor below the insert plate of the coil guide support, and the upstream lead-in plate. These modeling results based on the calculated high shear regions were in excellent agreement with the observed erosion sites in both location and the degree of erosion. Loss of the leading edge of the coil guide due to the erosion damage during the slurry mixing operation did not affect the erosion patterns on the tank floor. Calculations for a lower impeller speed showed similar erosion patterns but significantly reduced wall shear stresses

An experimental investigation of the thermal/fluid properties of the nitrate to ammonia and ceramic (NAC) product slurry

International Nuclear Information System (INIS)

Muguercia, I.; Lagos, L.; Yang, G.; Li, W.; Ebadian, M.A.; Mattus, A.J.; Lee, D.D.; Walker, J.W.; Hunt, R.D.

1994-01-01

Recently, a new immobilization technique for LLW, the Nitrate to Ammonia and Ceramic (NAC) process, has been developed. Instead of mixing the liquid waste form directly with the cement to make concrete blocks, the NAC process eliminates the nitrate from the LLW by converting it to ammonia gas. Aluminum particles are used as a reductant to complete this conversion. The final product of the NAC process is gibbsite, which can be further sintered to a ceramic waste form. Experimental tests are conducted to measure the apparent viscosity, the pressure drop, and the heat transfer coefficient of the pipe flow of the Nitrate to Ammonia and Ceramic (NAC) process product slurry. The tests indicate that the NAC product slurry exhibits a typical pseudoplastic fluid behavior. The pressure drop in the pipe flow is a function of the Reynolds number and the slurry temperature. The results also indicate that at a low slurry temperature, the slurry is uniformly heated peripherally. At a high slurry temperature, however, the slurry may be thermally stratified. In a straight pipe, the Nusselt number is reduced as the slurry temperature increases

Origin of high oxide to nitride polishing selectivity of ceria-based slurry in the presence of picolinic acid

International Nuclear Information System (INIS)

Wang Liang-Yong; Liu Bo; Song Zhi-Tang; Liu Wei-Li; Feng Song-Lin; David Huang; Babu, S.V

2011-01-01

We report on the investigation of the origin of high oxide to nitride polishing selectivity of ceria-based slurry in the presence of picolinic acid. The oxide to nitride removal selectivity of the ceria slurry with picolinic acid is as high as 76.6 in the chemical mechanical polishing. By using zeta potential analyzer, particle size analyzer, horizon profilometer, thermogravimetric analysis and Fourier transform infrared spectroscopy, the pre- and the post-polished wafer surfaces as well as the pre- and the post-used ceria-based slurries are compared. Possible mechanism of high oxide to nitride selectivity with using ceria-based slurry with picolinic acid is discussed. (interdisciplinary physics and related areas of science and technology)

Increased mineral oil bioavailability in slurries by monovalent cation-induced dispersion

International Nuclear Information System (INIS)

Jonge, H. de; Verstraten, J.M.

1995-01-01

Bioavailability of apolar contaminants is an important limiting factor for microbial reclamation of polluted soils. This paper describes a laboratory study of the relation between microaggregate stability and bioavailability of mineral oil in soil-water slurries. The stability of microaggregates in slurries is regulated by the valence and surface affinity of the cations in the system, and by the complexing anion P 2 O 7 4- (metaphosphate). A silt loam, contaminated with a weathered gas oil, was collected from an oil refinery site. Degradation rates were monitored in small-scale incubations at solid:liquid ratios of 1:5 (w/w). The solution contained Ca, Na, or K as the dominant cation. The levels of nutrients and metaphosphate were varied. Biodegradation rates increased with the sequence Ca 2 treatment. Measurements of the particle size distribution the slurry showed that an increase in the finer fractions qualitatively correlated with enhanced biodegradation. This is a strong indication that dispersion of the microaggregates increased bioavailability of the contaminant

ADVANCED COMPUTATIONAL MODEL FOR THREE-PHASE SLURRY REACTORS

International Nuclear Information System (INIS)

Ahmadi, Goodarz

2004-01-01

In this project, an Eulerian-Lagrangian formulation for analyzing three-phase slurry flows in a bubble column was developed. The approach used an Eulerian analysis of liquid flows in the bubble column, and made use of the Lagrangian trajectory analysis for the bubbles and particle motions. The bubble-bubble and particle-particle collisions are included the model. The model predictions are compared with the experimental data and good agreement was found An experimental setup for studying two-dimensional bubble columns was developed. The multiphase flow conditions in the bubble column were measured using optical image processing and Particle Image Velocimetry techniques (PIV). A simple shear flow device for bubble motion in a constant shear flow field was also developed. The flow conditions in simple shear flow device were studied using PIV method. Concentration and velocity of particles of different sizes near a wall in a duct flow was also measured. The technique of Phase-Doppler anemometry was used in these studies. An Eulerian volume of fluid (VOF) computational model for the flow condition in the two-dimensional bubble column was also developed. The liquid and bubble motions were analyzed and the results were compared with observed flow patterns in the experimental setup. Solid-fluid mixture flows in ducts and passages at different angle of orientations were also analyzed. The model predictions were compared with the experimental data and good agreement was found. Gravity chute flows of solid-liquid mixtures were also studied. The simulation results were compared with the experimental data and discussed A thermodynamically consistent model for multiphase slurry flows with and without chemical reaction in a state of turbulent motion was developed. The balance laws were obtained and the constitutive laws established

Ultrahigh-strength submicron-sized metallic glass wires

International Nuclear Information System (INIS)

Wang, Y.B.; Lee, C.C.; Yi, J.; An, X.H.; Pan, M.X.; Xie, K.Y.; Liao, X.Z.; Cairney, J.M.; Ringer, S.P.; Wang, W.H.

2014-01-01

In situ deformation experiments were performed in a transmission electron microscope to investigate the mechanical properties of submicron-sized Pd 40 Cu 30 Ni 10 P 20 metallic glass (MG) wires. Results show that the submicron-sized MG wires exhibit intrinsic ultrahigh tensile strength of ∼2.8 GPa, which is nearly twice as high as that in their bulk counterpart, and ∼5% elastic strain approaching the elastic limits. The tensile strength, engineering strain at failure and deformation mode of the submicron-sized MG wires depend on the diameter of the wires

Yield Stress Reduction of Radioactive Waste Slurries by Addition of Surfactants

International Nuclear Information System (INIS)

MICHAEL, STONE

2005-01-01

The Savannah River Site (SRS) and Hanford site are in the process of stabilizing millions of gallons of radioactive waste slurries remaining from production of nuclear materials for the Department of Energy (DOE). The Defense Waste Processing Facility (DWPF) at SRS is currently vitrifying the waste in borosilicate glass while the facilities at the Hanford site are in the design/construction phase. Both processes utilize slurry-fed joule heated melters to vitrify the waste slurries. The rheological properties of the waste slurries limit the total solids content that can be processed by the remote equipment during the pretreatment and melter feed processes. The use of a surface active agent, or surfactant, to increase the solids loading that can be fed to the melters would increase melt rate by reducing the heat load on the melter required to evaporate the water in the feed. The waste slurries are non-Newtonian fluids with rheological properties that were modeled using the Bingham Plastic mod el (this model is typically used by SRNL when studying the DWPF process1).The results illustrate that altering the surface chemistry of the particulates in the waste slurries can lead to a reduction in the yield stress. Dolapix CE64 is an effective surfactant over a wide range of pH values and was effective for all simulants tested. The effectiveness of the additive increased in DWPF simulants as the concentration of the additive was increased. No maxi main effectiveness was observed. Particle size measurements indicate that the additive acted as a flocculant in the DWPF samples and as a dispersant in the RPP samples

Slip casting nano-particle powders for making transparent ceramics

Science.gov (United States)

Kuntz, Joshua D [Livermore, CA; Soules, Thomas F [Livermore, CA; Landingham, Richard Lee [Livermore, CA; Hollingsworth, Joel P [Oakland, CA

2011-04-12

A method of making a transparent ceramic including the steps of providing nano-ceramic powders in a processed or unprocessed form, mixing the powders with de-ionized water, the step of mixing the powders with de-ionized water producing a slurry, sonifing the slurry to completely wet the powder and suspend the powder in the de-ionized water, separating very fine particles from the slurry, molding the slurry, and curing the slurry to produce the transparent ceramic.

Abrasive Particle Trajectories and Material Removal Non-Uniformity during CMP and Filtration Characteristics of CMP Slurries - A Simulation and Experimental Study

Science.gov (United States)

Rastegar, Vahid

Nanoscale finishing and planarization are integral process steps in multilevel metallization designs for integrated circuit (IC) manufacturing since it is necessary to ensure local and global surface planarization at each metal layer before depositing the next layer. Chemical mechanical planarization (CMP) has been widely recognized as the most promising technology to eliminate topographic variation and has allowed the construction of multilevel interconnection structures with a more regularly stacked sequence, resulting in better device performance [1]. Understanding fundamental of the CMP mechanisms can offer guidance to the control and optimization of the polishing processes. CMP kinematics based on slurry distribution and particle trajectories have a significant impact on MRR profiles. In this work a mathematical model to describe particle trajectories during chemical mechanical polishing was developed and extended to account for the effect of larger particles, particle location changes due to slurry dispensing and in-situ conditioning. Material removal rate (MRR) and within wafer non-uniformity (WIWNU) were determined based on the calculated particle trajectory densities. Rotary dynamics and reciprocating motion were optimized to obtain best MRR uniformity. Edge-fast MRR profile was discussed based on mechanical aspect of CMP. Using the model, we also investigated the effect of variable rotational speeds of wafer and pad, and of large particles on WIWNU and scratch growth. It was shown that the presence of even a small portion of large particles can deteriorate the WIWNU significantly and also lead to more scratches. Furthermore, it was shown that the in-situ conditioning improves the uniformity of the polished wafers. Furthermore, a combined experimental and computational study of fibrous filters for removal of larger abrasive particles from aqueous dispersions, essential to minimize defects during chemical mechanical polishing, was performed. Dilute aqueous

Comparison of Submicron Particles at a Rural and an Urban Site in the North China Plain during the December 2016 Heavy Pollution Episodes

Science.gov (United States)

Shen, Xiaojing; Sun, Junying; Zhang, Xiaoye; Zhang, Yangmei; Wang, Yaqiang; Tan, Kaiyan; Wang, Peng; Zhang, Lu; Qi, Xuefei; Che, Haochi; Zhang, Zhouxiang; Zhong, Junting; Zhao, Huarong; Ren, Sanxue

2018-02-01

An extensive field experiment for measurement of physical and chemical properties of aerosols was conducted at an urban site in the Chinese Academy of Meteorological Sciences (CAMS) in Beijing and at a rural site in Gucheng (GC), Hebei Province in December 2016. This paper compares the number size distribution of submicron particle matter (PM1, diameter PM1 number concentration at GC was twice that at CAMS, and the mass concentration was three times the amount at CAMS. It is found that the accumulation mode (100-850 nm) particles constituted the largest fraction of PM1 at GC, which was significantly correlated with the local coal combustion, as confirmed by a significant relationship between the accumulation mode and the absorption coefficient of soot particles. The high PM1 concentration at GC prevented the occurrence of new particle formation (NPF) events, while eight such events were observed at CAMS. During the NPF events, the mass fraction of sulfate increased significantly, indicating that sulfate played an important role in NPF. The contribution of regional transport to PM1 mass concentration was approximately 50% at both sites, same as that of the local emission. However, during the red-alert period when emission control took place, the contribution of regional transport was notably higher.

[Nasal submicron emulsion of Scutellariae Radix extract preparation technology research based on phase transfer of solute technology].

Science.gov (United States)

Shi, Ya-jun; Shi, Jun-hui; Chen, Shi-bin; Yang, Ming

2015-07-01

Based on the demand of nasal drug delivery high drug loadings, using the unique phase transfer of solute, integrating the phospholipid complex preparation and submicron emulsion molding process of Scutellariae Radix extract, the study obtained the preparation of the high drug loadings submicron emulsion of Scutellariae Radix extract. In the study of drug solution dispersion method, the uniformity of drug dispersed as the evaluation index, the traditional mixing method, grinding, homogenate and solute phase transfer technology were investigated, and the solute phase transfer technology was adopted in the last. With the adoption of new technology, the drug loading capacity reached 1.33% (phospholipid complex was 4%). The drug loading capacity was improved significantly. The transfer of solute method and timing were studied as follows,join the oil phase when the volume of phospholipid complex anhydrous ethanol solution remaining 30%, the solute phase transfer was completed with the continued recycling of anhydrous ethanol. After drug dissolved away to oil phase, the preparation technology of colostrum was determined with the evaluation index of emulsion droplet form. The particle size of submicron emulsion, PDI and stability parameters were used as evaluation index, orthogonal methodology were adopted to optimize the submicron emulsion ingredient and main influential factors of high pressure homogenization technology. The optimized preparation technology of Scutellariae Radix extract nasal submicron emulsion is practical and stable.

Submicron Emulsions and Their Applications in Oral Delivery.

Science.gov (United States)

Mundada, Veenu; Patel, Mitali; Sawant, Krutika

2016-01-01

A "submicron emulsion" is an isotropic mixture of drug, lipids, and surfactants, usually with hydrophilic cosolvents and with droplet diameters ranging from 10 to 500 nm. Submicron emulsions are of increasing interest in medicine due to their kinetic stability, high solubilizing capacity, and tiny globule size. Because of these properties, they have been applied in various fields, such as personal care, cosmetics, health care, pharmaceuticals, and agrochemicals. Submicron emulsions are by far the most advanced nanoparticulate systems for the systemic delivery of biologically active agents for controlled drug delivery and targeting. They are designed mainly for pharmaceutical formulations suitable for various routes of administration like parenteral, ocular, transdermal, and oral. This review article describes the marked potential of submicron emulsions for oral drug delivery owing to their numerous advantages like reduced first pass metabolism, inhibition of P-glycoprotein efflux system, and enhanced absorption via intestinal lymphatic pathway. To overcome the limitations of liquid dosage forms, submicron emulsions can be formulated into solid dosage forms such as solid self-emulsifying systems. This article covers various types of submicron emulsions like microemulsion, nanoemulsion, and self-emulsifying drug delivery system (SEDDS), and their potential pharmaceutical applications in oral delivery with emphasis on their advantages, limitations, and advancements.

Particle size distribution control of Pt particles used for particle gun

Science.gov (United States)

Ichiji, M.; Akiba, H.; Nagao, H.; Hirasawa, I.

2017-07-01

The purpose of this study is particle size distribution (PSD) control of submicron sized Pt particles used for particle gun. In this report, simple reaction crystallization is conducted by mixing H2PtCl6 and ascorbic acid. Without the additive, obtained Pt particles have broad PSD and reproducibility of experiment is low. With seeding, Pt particles have narrow PSD and reproducibility improved. Additionally, mean particle diameter of 100-700 nm is controlled by changing seeding amount. Obtained particles are successfully characterized as Pt by XRD results. Moreover, XRD spectra indicate that obtained particles are polycrystals. These experimental results suggest that seeding consumed nucleation, as most nuclei attached on the seed surface. This mechanism virtually restricted nucleation to have narrow PSD can be obtained.

ASSESSMENT OF THE ABILITY OF STANDARD SLURRY PUMPS TO MIX SOLIDS WITH LIQUIDS IN TANK 50H

Energy Technology Data Exchange (ETDEWEB)

Poirier, M.

2011-11-11

Tank 50H is the feed tank for the Saltstone Production Facility (SPF). In the summer of 2011, Tank 50H contained two standard slurry pumps and two quad volute slurry pumps. Current requirements for mixing operation is to run three pumps for one hour prior to initiating a feed transfer to SPF. Savannah River Site (SRS) Liquid Waste moved both of the Quad Volute pumps from Tank 50H to Tank 51H to replace pumps in Tank 51H that were failing. In addition, one of the standard pumps in Tank 50H exhibits high seal leakage and vibration. SRS Liquid Waste requested Savannah River National Laboratory (SRNL) to conduct a study to evaluate the feasibility of mixing the contents of Tank 50H with one to three standard slurry pumps. To determine the pump requirements to mix solids with liquids in Tank 50H, the author reviewed the pilot-scale blending work performed for the Small Column Ion Exchange Process (SCIX), SRNL computational fluid dynamics (CFD) modeling, Tank 50H operating experience, and the technical literature, and applied the results to Tank 50H to determine the number, size, and operating parameters of pumps needed to mix the solid particles with the liquid in Tank 50H. The analysis determined pump requirements to suspend the solids with no 'dead zones', but did not determine the pump requirements to produce a homogeneous suspension. In addition, the analysis determined the pump requirements to prevent the accumulation of a large amount of solid particles under the telescoping transfer pump. The conclusions from this analysis follow: (1) The analysis shows that three Quad Volute pumps should be able to suspend the solid particles expected ({approx}0.6 g/L insoluble solids, {approx}5 micron) in Tank 50H. (2) Three standard slurry pumps may not be able to suspend the solid particles in Tank 50H; (3) The ability of two Quad Volute pumps to fully suspend all of the solid particles in Tank 50H is marginal; and (4) One standard slurry pump should be able to

Precipitation scavenging of aerosol particles

International Nuclear Information System (INIS)

Radke, L.F.; Eltgroth, M.W.; Hobbs, P.V.

1978-01-01

The paper presents the results of precipitation scavenging measurements of particles in the atmosphere and in plumes which were obtained using an airborne measuring system. Attention is given to the so-called 'Greenfield gap' and collection efficiencies for submicron particles

Flow velocity analysis for avoidance of solids deposition during transport of Hanford tank waste slurries

International Nuclear Information System (INIS)

ESTEY, S.D.

1999-01-01

This engineering analysis calculates minimum slurry transport velocities intended to maintain suspensions of solid particulate in slurries. This transport velocity is also known as the slurry flow critical velocity. It is not universally recognized that a transfer line flow velocity in excess of the slurry critical velocity is a requirement to prevent solids deposition and possible line plugging. However, slurry critical velocity seems to be the most prevalent objective measure to prevent solids deposition in transfer lines. The following critical velocity correlations from the literature are investigated: Durand (1953), Spells (1955), Sinclair (1962), Zandi and Gavatos (1967), Babcock (1968), Shook (1969), and Oroskar and Turian (1980). The advantage of these critical velocity correlations is that their use is not reliant upon any measure of bulk slurry viscosity. The input parameters are limited to slurry phase densities and mass fractions, pipe diameter, particle diameter, and viscosity of the pure liquid phase of the slurry. Consequently, the critical velocity calculation does not require determination of system pressure drops. Generalized slurry properties can, therefore, be recommended if the slurry can be adequately described by these variables and if the liquid phase viscosity is known. Analysis of these correlations are presented, indicating that the Oroskar and Turian (1980) models appear to be more conservative for smaller particulate sizes, typically those less than 100 microns diameter. This analysis suggests that the current Tank Farms waste compatibility program criteria may be insufficient to prevent particulate solids settling within slurry composition ranges currently allowed by the waste compatibility program. However, in order to relate a critical velocity associated with a certain slurry composition to a system limit, a means of relating the system capabilities to the slurry composition must be found. Generally, this means expressing the bulk

Slurry pipeline design approach

Energy Technology Data Exchange (ETDEWEB)

Betinol, Roy; Navarro R, Luis [Brass Chile S.A., Santiago (Chile)

2009-12-19

Compared to other engineering technologies, the design of a commercial long distance Slurry Pipeline design is a relatively new engineering concept which gained more recognition in the mid 1960 's. Slurry pipeline was first introduced to reduce cost in transporting coal to power generating units. Since then this technology has caught-up worldwide to transport other minerals such as limestone, copper, zinc and iron. In South America, the use of pipeline is commonly practiced in the transport of Copper (Chile, Peru and Argentina), Iron (Chile and Brazil), Zinc (Peru) and Bauxite (Brazil). As more mining operations expand and new mine facilities are opened, the design of the long distance slurry pipeline will continuously present a commercially viable option. The intent of this paper is to present the design process and discuss any new techniques and approach used today to ensure a better, safer and economical slurry pipeline. (author)

Predicting transport requirements for radioactive-waste slurries

International Nuclear Information System (INIS)

Motyka, T.; Randall, C.T.

1983-01-01

A method for predicting the transport requirements of radioactive waste slurries was developed. This method involved preparing nonradioactive sludge slurries chemically similar to the actual high-level waste. The rheological and settling characteristics of these synthetic waste slurries were measured and found to compare favorably with data on actual defense waste slurries. Pressure drop versus flow rate data obtained fom a 2-in. slurry test loop confirmed the Bingham plastic behavior of the slurry observed during viscometry measurements. The pipeline tests, however, yielded friction factors 30 percent lower than those predicted from viscometry data. Differences between the sets of data were attributed to inherent problems in interpreting accurate yield-stress values of slurry suspensions with Couette-type viscometers. Equivalent lengths of fittings were also determined and found to be less than that of water at a specified flow rate

Characterization methodology for re-using marble slurry in industrial applications

Science.gov (United States)

Marras, Graziella; Careddu, Nicola; Peretti, Roberto; Bortolussi, Augusto

2017-04-01

In the effort towards waste minimization and circular economy, natural stone waste is one of the foremost parameter to turn scientific community attention. At this time, calcium carbonate has a great importance in industrial fields and currently there is the necessity of appreciate the potential value of marble waste and convert it into marketable products. A large amount of residues is produced in ornamental stone sector with different dimension and particle size. The research focused on marble slurry, recovered at the end of the treatment plant in the filter-press section. The aim of this paper is to propose a defined way to characterize marble slurry, primarily composed of micronized particles, in order to obtain useful data to make a comparison with market specifications. In particular the proposed characterization methodology follows the indicated steps: Leaching test (TCLP) - Grain size distribution and bulk density - Mineralogical analyses - X-Ray diffraction - Chemical analysis - Loss on ignition - SEM determination - Colorimetric and bright analysis. Marble slurry samples, collected by different dimension stone treatment plants in Orosei marble district (Sardinia - Italy), were analyzed by physical, mineralogical and chemical determinations and the obtained data were evaluated for compatibility with the CaCO3 specifications required by a definite industrial sector, seeing as how CaCO3 product specifications vary depending on the utilization. The importance of this investigation is to characterize completely the "waste" that must apply for further uses and to identify the feasibility to substitute marketable micronized CaCO3 with marble slurry. Further goal is to enhance the environmental advantages of re-using stone waste by reducing marble waste landfills and by applying raw material substitution, in accordance with regulatory requirements, thus pursuing the objective to convert natural stone waste into by-product with a renewed environmental and economic

Characterization and Correlation of Particle-Level Interactions to the Macroscopic Rheology of Powders, Granular Slurries, and Colloidal Suspensions

Energy Technology Data Exchange (ETDEWEB)

Poloski, Adam P.; Daniel, Richard C.; Rector, David R.; Bredt, Paul R.; Buck, Edgar C.; Berg, John C.; Saez, Avelino E.

2006-09-29

Hanford TRU tank sludges are complex mixtures of undissolved minerals and salt solids in an aqueous phase of high ionic strength. They show complex rheological behavior resulting from interactions at the macroscopic level, such as interparticle friction between grains in the coarse fraction, as well as from interactions at the nano-scale level, such as the agglomeration of colloidal particles. An understanding of how phenomena such as interparticle friction and aggregate stability under shear will allow better control of Hanford TRU tank sludges being processed for disposal. The project described in this report had two objectives. The first was to understand the physical properties and behavior of the Hanford transuranic (TRU) tank sludges under conditions that might exist during retrieval, treatment, packaging, and transportation for disposal at the Waste Isolation Pilot Plant (WIPP). The second objective was to develop a fundamental understanding of sludge physical properties by correlating the macroscopic behavior with interactions occurring at the particle/colloidal scale. These objectives were accomplished by: 1) developing continuum models for coarse granular slurries and 2) studying the behavior of colloidal agglomerates under shear and under irradiation.

Continuous separation of submicron particles using Angled electrodes

International Nuclear Information System (INIS)

Yunus, Nurul A Md; Green, Nicolas G

2008-01-01

Dielectrophoretic separation of particles is achieved by the generation of electric forces on the particles by non-uniform electric fields. This paper presents a technique based on negative dielectrophoresis in a novel design of electrode array for the non-contact separation of polarisable particles. Angled electrodes are used to generate a lateral force in a microfluidic channel separating a mixed stream of particles into distinct streams of constituent components and achieving a high degree of spatial separation.

An oilwell cement slurry additivated with bisphenol diglycidil ether/isophoronediamine-Kinetic analysis and multivariate modelings at slurry/HCl interfaces

International Nuclear Information System (INIS)

Cestari, Antonio R.; Vieira, Eunice F.S.; Tavares, Andrea M.G.; Andrade, Marcos A.S.

2009-01-01

Loss of zonal isolation in oilwell cementing operations leads to safety and environmental problems. The use of new cement slurries can help to solve this problem. In this paper, an epoxy-modified cement slurry was synthesized and characterized. The features of the modified slurries were evaluated in relation to a standard cement slurry (w/c = 0.50). A kinetic study of HCl interaction with the slurries was carried out using cubic molds. The Avrami kinetic model appears to be the most efficient in describing kinetic isotherms obtained from 25 to 55 deg. C. Type of slurry, HCl concentration and temperature effects were also evaluated in HCl adsorption onto cement slurries considering a 2 3 full factorial design. From the statistical analysis, it is inferred that the factor 'HCl concentration' has shown a profound influence on the numerical values of the Avrami kinetic constants. However, the best statistical fits were found using binary and tertiary interactive effects. It was found that the epoxy-modified cement slurry presents a good potential to be used in environmental-friendly oilwell operations.

Electron acceleration via high contrast laser interacting with submicron clusters

International Nuclear Information System (INIS)

Zhang Lu; Chen Liming; Wang Weiming; Yan Wenchao; Yuan Dawei; Mao Jingyi; Wang Zhaohua; Liu Cheng; Shen Zhongwei; Li Yutong; Dong Quanli; Lu Xin; Ma Jinglong; Wei Zhiyi; Faenov, Anatoly; Pikuz, Tatiana; Li Dazhang; Sheng Zhengming; Zhang Jie

2012-01-01

We experimentally investigated electron acceleration from submicron size argon clusters-gas target irradiated by a 100 fs, 10 TW laser pulses having a high-contrast. Electron beams are observed in the longitudinal and transverse directions to the laser propagation. The measured energy of the longitudinal electron reaches 600 MeV and the charge of the electron beam in the transverse direction is more than 3 nC. A two-dimensional particle-in-cell simulation of the interaction has been performed and it shows an enhancement of electron charge by using the cluster-gas target.

Recycling Pig Slurry Solid Fraction Compost as a Sound Absorber

Directory of Open Access Journals (Sweden)

Niccolò Pampuro

2018-01-01

Full Text Available The aim of this investigation was to determine the physical and acoustical properties of compacts made from composted pig slurry solid fraction (SF in order to assess the potential to recycle this agricultural waste as a sound absorber. The compacts were obtained by compression. The physical parameters investigated were bulk density, durability, and particle size distribution. The acoustical features of the compacts were studied with an impedance tube device in order to verify the acoustic absorption coefficient. Two composts were prepared: pig SF compost without a bulking agent (SSFC and pig SF compost with wood chips as a bulking agent (WCC. The study’s results indicated that compost particles dimension played a key role in the physical and acoustical properties of the compacts: the smaller the particles, the higher the physical and acoustical properties of the compacts. The densification process increased the bulk density of the investigated composts up to 690 kg m−3 for SSFC and 660 kg m−3 for WWC, with, respectively, medium (77.9% and low (66.5% durability. The addition of woody bulking agent significantly reduced the absorption coefficient: the best results, in terms of potential use as a sound absorber, were observed for compacts made from composted pig slurry solid fraction without the addition of wood chips.

Attenuation measurements of ultrasound in a kaolin-water slurry. A linear dependence upon frequency

International Nuclear Information System (INIS)

Greenwood, M.S.; Mai, J.L.; Good, M.S.

1993-01-01

The attenuation of ultrasound through a kaolin-water slurry was measured for frequencies ranging from 0.5 to 3.0 MHz. The maximum concentration of the slurry was for a weight percentage of 44% (or a volume fraction of 0.24). The goal of these measurements was to assess the feasibility of using ultrasonic attenuation to determine the concentration of a slurry of known composition. The measurements were obtained by consecutively adding kaolin to the slurry and measuring the attenuation at each concentration. After reaching a maximum concentration a dilution technique was used, in which an amount of slurry was removed and water was added, to obtain the attenuation as a function of the concentration. The dilution technique was the more effective method to obtain calibration data. These measurements were carried out using two transducers, having a center frequency of 2.25 MHz, separated by 0.1016m (4.0 in.). The maximum attenuation measured in these experiments was about 100Np/m, but the experimental apparatus has the capability of measuring a larger attenuation if the distance between the two transducers is decreased. For a given frequency, the data show that ln V/V 0 depends linearly upon the volume fraction (V is the received voltage for the slurry and V 0 is that obtained for water). This indicated that each particle acts independently in attenuating ultrasound. 12 refs., 7 figs., 3 tabs

Particle size distribution and composition in a mechanically ventilated school building during air pollution episodes.

Science.gov (United States)

Parker, J L; Larson, R R; Eskelson, E; Wood, E M; Veranth, J M

2008-10-01

Particle count-based size distribution and PM(2.5) mass were monitored inside and outside an elementary school in Salt Lake City (UT, USA) during the winter atmospheric inversion season. The site is influenced by urban traffic and the airshed is subject to periods of high PM(2.5) concentration that is mainly submicron ammonium and nitrate. The school building has mechanical ventilation with filtration and variable-volume makeup air. Comparison of the indoor and outdoor particle size distribution on the five cleanest and five most polluted school days during the study showed that the ambient submicron particulate matter (PM) penetrated the building, but indoor concentrations were about one-eighth of outdoor levels. The indoor:outdoor PM(2.5) mass ratio averaged 0.12 and particle number ratio for sizes smaller than 1 microm averaged 0.13. The indoor submicron particle count and indoor PM(2.5) mass increased slightly during pollution episodes but remained well below outdoor levels. When the building was occupied the indoor coarse particle count was much higher than ambient levels. These results contribute to understanding the relationship between ambient monitoring station data and the actual human exposure inside institutional buildings. The study confirms that staying inside a mechanically ventilated building reduces exposure to outdoor submicron particles. This study supports the premise that remaining inside buildings during particulate matter (PM) pollution episodes reduces exposure to submicron PM. New data on a mechanically ventilated institutional building supplements similar studies made in residences.

Deposition Velocities of Non-Newtonian Slurries in Pipelines: Complex Simulant Testing

Energy Technology Data Exchange (ETDEWEB)

Poloski, Adam P.; Bonebrake, Michael L.; Casella, Andrew M.; Johnson, Michael D.; Toth, James J.; Adkins, Harold E.; Chun, Jaehun; Denslow, Kayte M.; Luna, Maria; Tingey, Joel M.

2009-07-01

One of the concerns expressed by the External Flowsheet Review Team (EFRT) is about the potential for pipe plugging at the Waste Treatment and Immobilization Plant (WTP). Per the review’s executive summary, “Piping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging.” To evaluate the potential for plugging, deposition-velocity tests were performed on several physical simulants to determine whether the design approach is conservative. Deposition velocity is defined as the velocity below which particles begin to deposit to form a moving bed of particles on the bottom of a straight horizontal pipe during slurry-transport operations. The deposition velocity depends on the system geometry and the physical properties of the particles and fluid. An experimental program was implemented to test the stability-map concepts presented in WTP-RPT-175 Rev. 01. Two types of simulant were tested. The first type of simulant was similar to the glass-bead simulants discussed in WTP-RPT-175 Rev. 0 ; it consists of glass beads with a nominal particle size of 150 µm in a kaolin/water slurry. The initial simulant was prepared at a target yield stress of approximately 30 Pa. The yield stress was then reduced, stepwise, via dilution or rheological modifiers, ultimately to a level of <1 Pa. At each yield-stress step, deposition-velocity testing was performed. Testing over this range of yield-stress bounds the expected rheological operating window of the WTP and allows the results to be compared to stability-map predictions for this system. The second simulant was a precipitated hydroxide that simulates HLW pretreated sludge from Hanford waste tank AZ-101. Testing was performed in a manner similar to that for the first simulant over a wide range of yield stresses; however, an additional test of net-positive suction-head required (NPSHR

Bio-slurry as fertilizer : is bio-slurry from household digesters a better fertilizer than manure? : a literature review

NARCIS (Netherlands)

Bonten, L.T.C.; Zwart, K.B.; Rietra, R.P.J.J.; Postma, R.; Haas, de M.J.G.; Nysingh, S.L.

2014-01-01

In many developing countries manure is anaerobically digested to produce biogas. The residue of manure digestion, bio-slurry, can be used as fertilizer for crop production and aquaculture. This study compared bio-slurry and manure as fertilizers. Nutrients in bio-slurry, especially nitrogen, are

Enhancement of melting heat transfer of ice slurries by an injection flow in a rectangular cross sectional horizontal duct

International Nuclear Information System (INIS)

Fujii, Kota; Yamada, Masahiko

2013-01-01

Ice slurries are now commonly used as cold thermal storage materials, and have the potential to be applied to other engineering fields such as quenching metals to control properties, emergency cooling systems, and preservation of food and biomaterials at low temperatures. Although ice slurries have been widely utilized because of their high thermal storage densities, previous studies have revealed that the latent heat of ice particles is not completely released on melting because of insufficient contact between the ice particles and a heated surface. In this study, an injection flow that was bifurcated from the main flow of an ice slurry was employed to promote melting heat transfer of ice particles on a horizontal heated surface. The effects of injection angle and injection flow rate on local heat transfer coefficients and heat transfer coefficient ratios were determined experimentally. The results show that from two to three times higher heat transfer coefficients can be obtained by using large injection flow rates and injection angles. However, low injection angles improved the utilization rate of the latent heat of ice near the injection point by approximately a factor of two compared to that without injection. -- Highlights: • Melting of ice slurries were enhanced by the injection under constant total flow rate. • Contribution of ice particles and their latent heat to heat transfer was investigated. • Effect of velocity ratio of injection to that of main flow was examined. • Effect of the angle of injection flow to the main flow was also examined. • Appropriate conditions for the use of latent heat of ice and heat transfer did not coincide

Slurry flow principles and practice

CERN Document Server

Shook, C A; Brenner, Howard

2015-01-01

Slurry Flow: Principles and Practice describes the basic concepts and methods for understanding and designing slurry flow systems, in-plan installations, and long-distance transportation systems. The goal of this book is to enable the design or plant engineer to derive the maximum benefit from a limited amount of test data and to generalize operating experience to new situations. Design procedures are described in detail and are accompanied by illustrative examples needed by engineers with little or no previous experience in slurry transport.The technical literature in this field is extensive:

Kinetics of CO Oxidation over Unloaded and Pd-Loaded α-Fe2O3 Spherical Submicron Powder Catalysts: Photoacoustic Investigations at Low Pressure

Directory of Open Access Journals (Sweden)

Joong-Seok Roh

2018-02-01

Full Text Available In this study, α-Fe2O3 spherical particles with an average diameter of approximately 200 nm were synthesized by a solvothermal method for use as both a catalyst and medium for a Pd catalyst. The kinetics of CO oxidation over powders of α-Fe2O3 spherical particles and 14 wt % Pd/α-Fe2O3 spherical particles were measured in a static reactor by using a CO2 laser-based photoacoustic technique. The total pressure was fixed at 40 Torr for the CO/O2/N2 mixture for temperatures in the range of 225–350 °C. The variation in the CO2 photoacoustic signal with the CO2 concentration during CO oxidation was recorded as a function of time, and the CO2 photoacoustic data at the early reaction stage was used to estimate the rates of CO2 formation. Based on plots of ln(rate vs. 1/T, apparent activation energies were calculated as 13.4 kcal/mol for the α-Fe2O3 submicron powder and 13.2 kcal/mol for the 14 wt % Pd/α-Fe2O3 submicron powder. Reaction orders with respect to CO and O2 were determined from the rates measured at various partial pressures of CO and O2 at 350 °C. The zero-order of the reaction with respect to Po2 was observed for CO oxidation over α-Fe2O3 submicron powder, while 0.48 order to Po2 was observed for CO oxidation over Pd/α-Fe2O3 submicron powder. The partial orders with respect to PCO were determined as 0.58 and 0.54 for the α-Fe2O3, and the Pd/α-Fe2O3 submicron powders, respectively. The kinetic results obtained from both catalysts were compared with those for the α-Fe2O3 fine powder catalysts and were used to understand the reaction mechanism.

Seismic signals of snow-slurry lahars in motion: 25 September 2007, Mt Ruapehu, New Zealand

Science.gov (United States)

Cole, S. E.; Cronin, S. J.; Sherburn, S.; Manville, V.

2009-05-01

Detection of ground shaking forms the basis of many lahar-warning systems. Seismic records of two lahar types at Ruapehu, New Zealand, in 2007 are used to examine their nature and internal dynamics. Upstream detection of a flow depends upon flow type and coupling with the ground. 3-D characteristics of seismic signals can be used to distinguish the dominant rheology and gross physical composition. Water-rich hyperconcentrated flows are turbulent; common inter-particle and particle-substrate collisions engender higher energy in cross-channel vibrations relative to channel-parallel. Plug-like snow-slurry lahars show greater energy in channel-parallel signals, due to lateral deposition insulating channel margins, and low turbulence. Direct comparison of flow size must account for flow rheology; a water-rich lahar will generate signals of greater amplitude than a similar-sized snow-slurry flow.

High Proportions of Sub-micron Particulate Matter in Icelandic Dust Storms in 2015

Science.gov (United States)

Dagsson Waldhauserova, Pavla; Arnalds, Olafur; Olafsson, Haraldur; Magnusdottir, Agnes

2017-04-01

Iceland is extremely active dust region and desert areas of over 44,000 km2 acknowledge Iceland as the largest Arctic and European desert. Frequent dust events, up to 135 dust days annually, transport dust particles far distances towards the Arctic and Europe. Satellite MODIS pictures have revealed dust plumes exceeding 1,000 km. The annual dust deposition was calculated as 40.1 million tons yr-1. Two dust storms were measured in transverse horizontal profile about 90 km far from different dust sources in southwestern Iceland in the summer of 2015. Aerosol monitor DustTrak DRX 8533EP was used to measure PM mass concentrations corresponding to PM1, PM2.5, PM4, PM10 and the total PM15 at several places within the dust plume. Images from camera network operated by the Icelandic Road and Coastal Administration were used to estimate the visibility and spatial extent of measured dust events. A numerical simulation of surface winds was carried out with the numerical model HIRLAM with horizontal resolution of 5 km and used to calculate the total dust flux from the sources. The in situ measurements inside the dust plumes showed that aeolian dust can be very fine. The study highlights that suspended volcanic dust in Iceland causes air pollution with extremely high PM1 concentrations comparable to the polluted urban stations in Europe or Asia rather than reported dust event observations from around the world. The PM1/PM2.5 ratios are generally low during dust storms outside of Iceland, much lower than > 0.9 and PM1/PM10 ratios of 0.34-0.63 found in our study. It shows that Icelandic volcanic dust consists of higher proportion of submicron particles compared to crustal dust. The submicron particles are predicted to travel long distances. Moreover, such submicron particles pose considerable health risk because of high potential for entering the lungs. Icelandic volcanic glass has often fine pipe-vesicular structures known from asbestos and high content of heavy metals. Previous

Solar cells based on particulate structure of active layer: Investigation of light absorption by an ordered system of spherical submicron silicon particles

Science.gov (United States)

Miskevich, Alexander A.; Loiko, Valery A.

2015-12-01

Enhancement of the performance of photovoltaic cells through increasing light absorption due to optimization of an active layer is considered. The optimization consists in creation of particulate structure of active layer. The ordered monolayers and multilayers of submicron crystalline silicon (c-Si) spherical particles are examined. The quasicrystalline approximation (QCA) and the transfer matrix method (TMM) are used to calculate light absorption in the wavelength range from 0.28 μm to 1.12 μm. The integrated over the terrestial solar spectral irradiance "Global tilt" ASTM G173-03 absorption coefficient is calculated. In the wavelength range of small absorption index of c-Si (0.8-1.12 μm) the integral absorption coefficient of monolayer can be more than 20 times higher than the one of the plane-parallel plate of the equivalent volume of material. In the overall considered range (0.28-1.12 μm) the enhancement factor up to ~1.45 for individual monolayer is observed. Maximum value of the spectral absorption coefficient approaches unity for multilayers consisting of large amount of sparse monolayers of small particles. Multilayers with variable concentration and size of particles in the monolayer sequences are considered. Absorption increasing by such gradient multilayers as compared to the non-gradient ones is illustrated. The considered structures are promising for creation of high efficiency thin-film solar cells.

Studies on Slurry Design Fundamentals for Advanced CMP Applications

KAUST Repository

Basim, G. B.; Karagoz, A.; Ozdemir, Z.; Vakarelski, Ivan Uriev; Chen, Long

2013-01-01

New developments and device performance requirements in microelectronics industry add to the challenges in chemical mechanical planarization (CMP) process. One of the recently introduced materials is germanium which enables improved performance through better channel mobility in shallow trench isolation (STI) applications. This paper reports on the slurry design alternatives for Ge CMP with surfactant mediation to improve on the silica/germanium selectivity using colloidal silica slurry. In addition to the standard CMP tests to evaluate the material removal rates, atomic force microscopy (AFM) based wear tests were also conducted to evaluate single particle-surface interaction of the polishing system. Furthermore, nature of the surface oxide film of germanium was studied through contact angle measurements and surface roughness tested by AFM. It was observed that the CMP selectivity of the silica/germanium system and defectivity control were possible with a reasonable material removal rate value by using self-assembled structures of cationic surfactants.

Studies on Slurry Design Fundamentals for Advanced CMP Applications

KAUST Repository

Basim, G. B.

2013-06-14

New developments and device performance requirements in microelectronics industry add to the challenges in chemical mechanical planarization (CMP) process. One of the recently introduced materials is germanium which enables improved performance through better channel mobility in shallow trench isolation (STI) applications. This paper reports on the slurry design alternatives for Ge CMP with surfactant mediation to improve on the silica/germanium selectivity using colloidal silica slurry. In addition to the standard CMP tests to evaluate the material removal rates, atomic force microscopy (AFM) based wear tests were also conducted to evaluate single particle-surface interaction of the polishing system. Furthermore, nature of the surface oxide film of germanium was studied through contact angle measurements and surface roughness tested by AFM. It was observed that the CMP selectivity of the silica/germanium system and defectivity control were possible with a reasonable material removal rate value by using self-assembled structures of cationic surfactants.

Improved Fischer-Tropsch Slurry Reactors

International Nuclear Information System (INIS)

Lucero, Andrew

2009-01-01

The conversion of synthesis gas to hydrocarbons or alcohols involves highly exothermic reactions. Temperature control is a critical issue in these reactors for a number of reasons. Runaway reactions can be a serious safety issue, even raising the possibility of an explosion. Catalyst deactivation rates tend to increase with temperature, particularly of there are hot spots in the reactor. For alcohol synthesis, temperature control is essential because it has a large effect on the selectivity of the catalysts toward desired products. For example, for molybdenum disulfide catalysts unwanted side products such as methane, ethane, and propane are produced in much greater quantities if the temperature increases outside an ideal range. Slurry reactors are widely regarded as an efficient design for these reactions. In a slurry reactor a solid catalyst is suspended in an inert hydrocarbon liquid, synthesis gas is sparged into the bottom of the reactor, un-reacted synthesis gas and light boiling range products are removed as a gas stream, and heavy boiling range products are removed as a liquid stream. This configuration has several positive effects for synthesis gas reactions including: essentially isothermal operation, small catalyst particles to reduce heat and mass transfer effects, capability to remove heat rapidly through liquid vaporization, and improved flexibility on catalyst design through physical mixtures in addition to use of compositions that cannot be pelletized. Disadvantages include additional mass transfer resistance, potential for significant back-mixing on both the liquid and gas phases, and bubble coalescence. In 2001 a multiyear project was proposed to develop improved FT slurry reactors. The planned focus of the work was to improve the reactors by improving mass transfer while considering heat transfer issues. During the first year of the project the work was started and several concepts were developed to prepare for bench-scale testing. Power

Remote Laser Diffraction Particle Size Distribution Analyzer

Energy Technology Data Exchange (ETDEWEB)

Batcheller, Thomas Aquinas; Huestis, Gary Michael; Bolton, Steven Michael

2001-03-01

In support of a radioactive slurry sampling and physical characterization task, an “off-the-shelf” laser diffraction (classical light scattering) particle size analyzer was utilized for remote particle size distribution (PSD) analysis. Spent nuclear fuel was previously reprocessed at the Idaho Nuclear Technology and Engineering Center (INTEC—formerly recognized as the Idaho Chemical Processing Plant) which is on DOE’s INEEL site. The acidic, radioactive aqueous raffinate streams from these processes were transferred to 300,000 gallon stainless steel storage vessels located in the INTEC Tank Farm area. Due to the transfer piping configuration in these vessels, complete removal of the liquid can not be achieved. Consequently, a “heel” slurry remains at the bottom of an “emptied” vessel. Particle size distribution characterization of the settled solids in this remaining heel slurry, as well as suspended solids in the tank liquid, is the goal of this remote PSD analyzer task. A Horiba Instruments Inc. Model LA-300 PSD analyzer, which has a 0.1 to 600 micron measurement range, was modified for remote application in a “hot cell” (gamma radiation) environment. This technology provides rapid and simple PSD analysis, especially down in the fine and microscopic particle size regime. Particle size analysis of these radioactive slurries down in this smaller range was not previously achievable—making this technology far superior than the traditional methods used. Successful acquisition of this data, in conjunction with other characterization analyses, provides important information that can be used in the myriad of potential radioactive waste management alternatives.

Improvement of dissolution behavior of poorly water soluble drugs by biodegradable polymeric submicron carriers containing sparingly methylated β-cyclodextrin.

Science.gov (United States)

Singhavi, Dilesh J; Khan, Shagufta; Yeole, Pramod G

2013-04-01

The objective of this study was to develop submicron carriers of two drugs that are practically insoluble in water, i.e. meloxicam and aceclofenac, to improve their dissolution behavior. The phase solubility of the drugs was studied using different concentrations of sparingly methylated β-cyclodextrin, Kleptose(®) Crysmeβ (Crysmeb), in the presence and absence of 0.2 % w/v water-soluble chitosan. Drug-loaded submicron particles (SMPs) were prepared using chitosan chlorhydrate and Crysmeb by the ionotropic gelation method. The SMPs were characterized in terms of powder X-ray diffraction, Fourier transforms infrared spectroscopy, size determination, process yield, drug loading, encapsulation efficiency, surface morphology and in vitro release. The drug loading in the SMPs was enhanced in the presence of Crysmeb. The in vitro drug release was found to be enhanced with SMPs prepared using higher concentrations of Crysmeb. These results indicate that SMPs formed from chitosan chlorhydrate and Crysmeb are promising submicron carriers for enhancing the dissolution of meloxicam and aceclofenac.

Biogas slurry pricing method based on nutrient content

Science.gov (United States)

Zhang, Chang-ai; Guo, Honghai; Yang, Zhengtao; Xin, Shurong

2017-11-01

In order to promote biogas-slurry commercialization, A method was put forward to valuate biogas slurry based on its nutrient contents. Firstly, element contents of biogas slurry was measured; Secondly, each element was valuated based on its market price, and then traffic cost, using cost and market effect were taken into account, the pricing method of biogas slurry were obtained lastly. This method could be useful in practical production. Taking cattle manure raw meterial biogas slurry and con stalk raw material biogas slurry for example, their price were 38.50 yuan RMB per ton and 28.80 yuan RMB per ton. This paper will be useful for recognizing the value of biogas projects, ensuring biogas project running, and instructing the cyclic utilization of biomass resources in China.

Synthesis and surface properties of submicron barium sulfate particles

International Nuclear Information System (INIS)

Zhang Ming; Zhang Bao; Li Xinhai; Yin Zhoulan; Guo Xueyi

2011-01-01

Barium sulfate particles were synthesized in the presence of EDTA at room temperature. X-ray diffractometry (XRD), Fourier transform infrared resonance (FTIR) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of BaSO 4 particles. The effect of the preparation parameters on the particle size distribution and morphology was investigated. The conditional formation constants of Ba-EDTA at different pH values were calculated. The results show that the size and morphology of BaSO 4 particles can be effectively controlled by adding EDTA in the precipitation process. Among all the operation conditions, the pH value has significant effect on the particle size. The obtained barium sulfate particles are spherical and well dispersed at pH = 9-10. Zeta potentials of BaSO 4 were measured at different pH. The isoelectric point (IEP) of barium sulfate colloid appears at pH 6.92. The model of the solid-solution interface at a particle of BaSO 4 was presented. The FTIR result indicates that the surface of the prepared BaSO 4 absorbs the functional groups of EDTA, which lower the IEP of the barium sulfate particles.

Synthesis and surface properties of submicron barium sulfate particles

Energy Technology Data Exchange (ETDEWEB)

Zhang Ming, E-mail: csu.light@yahoo.com.cn [College of Chemistry and Chemical Engineering, Zhaoqing University, Zhaoqing 526061 (China); School of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Zhang Bao; Li Xinhai [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); Yin Zhoulan [School of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Guo Xueyi [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China)

2011-10-15

Barium sulfate particles were synthesized in the presence of EDTA at room temperature. X-ray diffractometry (XRD), Fourier transform infrared resonance (FTIR) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of BaSO{sub 4} particles. The effect of the preparation parameters on the particle size distribution and morphology was investigated. The conditional formation constants of Ba-EDTA at different pH values were calculated. The results show that the size and morphology of BaSO{sub 4} particles can be effectively controlled by adding EDTA in the precipitation process. Among all the operation conditions, the pH value has significant effect on the particle size. The obtained barium sulfate particles are spherical and well dispersed at pH = 9-10. Zeta potentials of BaSO{sub 4} were measured at different pH. The isoelectric point (IEP) of barium sulfate colloid appears at pH 6.92. The model of the solid-solution interface at a particle of BaSO{sub 4} was presented. The FTIR result indicates that the surface of the prepared BaSO{sub 4} absorbs the functional groups of EDTA, which lower the IEP of the barium sulfate particles.

An Experimental Study of Portland Cement and Superfine Cement Slurry Grouting in Loose Sand and Sandy Soil

Directory of Open Access Journals (Sweden)

Weijing Yao

2018-04-01

Full Text Available Grouting technology is widely applied in the fields of geotechnical engineering in infrastructure. Loose sand and sandy soil are common poor soils in tunnel and foundation treatments. It is necessary to use superfine cement slurry grouting in the micro-cracks of soil. The different effectiveness of Portland cement slurry and superfine cement slurry in sandy soil by the laboratory grouting experiment method were presented in this paper. The grouting situations of superfine cement slurry injected into sand and sandy soil were explored. The investigated parameters were the dry density, wet density, moisture content, internal friction angle, and cohesion force. The results show that the consolidation effect of superfine cement is better than that of Portland cement due to the small size of superfine cement particles. The superfine cement can diffuse into the sand by infiltration, extrusion, and splitting. When the water–cement ratio of superfine cement slurry is less than 2:1 grouting into loose sand, the dry and wet density decrease with the increase in the water–cement ratio, while the moisture content and cohesive force gradually increase. When the water–cement ratio of superfine cement slurry is 1:1 grouting into loose sand and sandy soil, the dry density, wet density, and cohesive force of loose sand are larger than those of sandy soil. The results of the experiment may be relevant for engineering applications.

Atomization of JP-10/B4C gelled slurry fuel

OpenAIRE

Guglielmi, John David

1992-01-01

The atomization of a gelled boron slurry fuel using two commercially available airblast atomizers was studied at atmospheric pressure in non-reacting flow. The atomization of water was also characterized for comparison. Each atomizer was operated at two different liquid mass flow rates and several air/ fuel ratios. Drop size distribution was measured using a Malvern 2600 HSD Laser Diffraction Particle Sizer, Drop sizes acceptable for use in ramjet combustors could be obtained f...

Slurry pipeline technology: an overview

Energy Technology Data Exchange (ETDEWEB)

Chapman, Jay P. [Pipeline Systems Incorporated (PSI), Belo Horizonte, MG (Brazil); Lima, Rafael; Pinto, Daniel; Vidal, Alisson [Ausenco do Brasil Engenharia Ltda., Nova Lima, MG (Brazil). PSI Div.

2009-12-19

Slurry pipelines represent an economical and environmentally friendly transportation means for many solid materials. This paper provides an over-view of the technology, its evolution and current Brazilian activity. Mineral resources are increasingly moving farther away from ports, processing plants and end use points, and slurry pipelines are an important mode of solids transport. Application guidelines are discussed. State-of-the-Art technical solutions such as pipeline system simulation, pipe materials, pumps, valves, automation, telecommunications, and construction techniques that have made the technology successful are presented. A discussion of where long distant slurry pipelines fit in a picture that also includes thickened and paste materials pipe lining is included. (author)

Physico-chemical principles of slurries

Energy Technology Data Exchange (ETDEWEB)

Leiber, C.O.

1984-12-01

Spectacular accidents have occurred in mining with products considered non-explosive. In view of the disastrous consequences of these accidents, the old 'Anfo' idea has been revived (= ammonium nitrate and fuel oil). Experiments in wet wells have led to the development of a new type of non-explosive blasting agents, i.e. the so-called slurries. Detonation of these slurries is divided into an energy release process and an energy conversion process. The basic mechanisms are described with a view to practical problems, e.g. detonation control, temperature dependence of the blasting characteristics, pressure dependence of the ignition process, critical diameter, slurry state problems, and sensitivity.

Ammonia abatement by slurry acidification

DEFF Research Database (Denmark)

Petersen, Søren O.; Hutchings, Nicholas John; Hafner, Sasha D.

2016-01-01

sections with 30-32 pigs with or without daily adjustment of slurry pH to below 6. Ammonia losses from reference sections with untreated slurry were between 9.5 and 12.4% of N excreted, and from sections with acidified slurry between 3.1 and 6.2%. Acidification reduced total emissions of NH3 by 66 and 71......% in spring and autumn experiments, and by 44% in the summer experiment. Regression models were used to investigate sources and controls of NH3 emissions. There was a strong relationship between NH3 emissions and ventilation rate during spring and autumn, but less so during summer where ventilation rates were...

Chemical Hydride Slurry for Hydrogen Production and Storage

Energy Technology Data Exchange (ETDEWEB)

McClaine, Andrew W

2008-09-30

The purpose of this project was to investigate and evaluate the attractiveness of using a magnesium chemical hydride slurry as a hydrogen storage, delivery, and production medium for automobiles. To fully evaluate the potential for magnesium hydride slurry to act as a carrier of hydrogen, potential slurry compositions, potential hydrogen release techniques, and the processes (and their costs) that will be used to recycle the byproducts back to a high hydrogen content slurry were evaluated. A 75% MgH₂ slurry was demonstrated, which was just short of the 76% goal. This slurry is pumpable and storable for months at a time at room temperature and pressure conditions and it has the consistency of paint. Two techniques were demonstrated for reacting the slurry with water to release hydrogen. The first technique was a continuous mixing process that was tested for several hours at a time and demonstrated operation without external heat addition. Further work will be required to reduce this design to a reliable, robust system. The second technique was a semi-continuous process. It was demonstrated on a 2 kWh scale. This system operated continuously and reliably for hours at a time, including starts and stops. This process could be readily reduced to practice for commercial applications. The processes and costs associated with recycling the byproducts of the water/slurry reaction were also evaluated. This included recovering and recycling the oils of the slurry, reforming the magnesium hydroxide and magnesium oxide byproduct to magnesium metal, hydriding the magnesium metal with hydrogen to form magnesium hydride, and preparing the slurry. We found that the SOM process, under development by Boston University, offers the lowest cost alternative for producing and recycling the slurry. Using the H2A framework, a total cost of production, delivery, and distribution of $4.50/kg of hydrogen delivered or $4.50/gge was determined. Experiments performed at Boston

Low frequency aeration of pig slurry affects slurry characteristics and emissions of greenhouse gases and ammonia.

Science.gov (United States)

Calvet, Salvador; Hunt, John; Misselbrook, Tom H

2017-07-01

Low frequency aeration of slurries may reduce ammonia (NH 3 ) and methane (CH 4 ) emissions without increasing nitrous oxide (N 2 O) emissions. The aim of this study was to quantify this potential reduction and to establish the underlying mechanisms. A batch experiment was designed with 6 tanks with 1 m 3 of pig slurry each. After an initial phase of 7 days when none of the tanks were aerated, a second phase of 4 weeks subjected three of the tanks to aeration (2 min every 6 h, airflow 10 m 3  h -1 ), whereas the other three tanks remained as a control. A final phase of 9 days was established with no aeration in any tank. Emissions of NH 3 , CH 4 , carbon dioxide (CO 2 ) and N 2 O were measured. In the initial phase no differences in emissions were detected, but during the second phase aeration increased NH 3 emissions by 20% with respect to the controls (8.48 vs. 7.07 g m -3  [slurry] d -1 , P emissions were 40% lower in the aerated tanks (2.04 vs. 3.39 g m -3  [slurry] d -1 , P emissions remained after the aeration phase had finished. No effect was detected for CO 2 , and no relevant N 2 O emissions were detected during the experiment. Our results demonstrate that low frequency aeration of stored pig slurry increases slurry pH and increases NH 3 emissions.

CEMENT SLURRIES FOR GEOTHERMAL WELLS CEMENTING

Directory of Open Access Journals (Sweden)

Nediljka Gaurina-Međimurec

1994-12-01

Full Text Available During a well cementing special place belongs to the cement slurry design. To ensure the best quality of cementing, a thorough understanding of well parameters is essential, as well as behaviour of cement slurry (especially at high temperatures and application of proven cementing techniques. Many cement jobs fail because of bad job planning. Well cementing without regarding what should be accomplished, can lead to well problems (channels in the cement, unwanted water, gas or fluid production, pipe corrosion and expensive well repairs. Cementing temperature conditions are important because bot-tomhole circulating temperatures affect slurry thickening time, arheology, set time and compressive strength development. Knowing the actual temperature which cement encounters during placement allows the selection of proper cementing materials for a specific application. Slurry design is affected by well depth, bottom hole circulating temperature and static temperature, type or drilling fluid, slurry density, pumping time, quality of mix water, fluid loss control, flow regime, settling and free water, quality of cement, dry or liquid additives, strength development, and quality of the lab cement testing and equipment. Most Portland cements and Class J cement have shown suitable performances in geot-hermal wells. Cement system designs for geothermal wells differ from those for conventional high temperature oil and gas wells in the exclusive use of silica flour instead of silica sand, and the avoidance of fly ash as an extender. In this paper, Portland cement behaviour at high temperatures is described. Cement slurry and set cement properties are also described. Published in literature, the composition of cement slurries which were tested in geothermal conditions and which obtained required compressive strength and water permeability are listed. As a case of our practice geothermal wells Velika Ciglena-1 and Velika Ciglena-la are described.

Particle size control of detergents in mixed flow spray dryers

Directory of Open Access Journals (Sweden)

Mark Jonathan Crosby

2015-03-01

Full Text Available Particle size is a key quality parameter of a powder detergent as it determines its performance, the bulk density and the look and feel of the product. Consequently, it is essential that particle size is controlled to ensure the consistency of performance when comparing new formulations. The majority of study reported in the literature relating to particle size control, focuses on the spray produced by the atomisation technique. One approach advocated to achieve particle size control is the manipulation of the ratio of the mass slurry rate and mass flow rate of gas used for atomisation. Within this study, ratio control was compared with an automatic cascade loop approach using online measurements of the powder particle size on a small-scale pilot plant. It was concluded that cascade control of the mean particle size, based on manipulating the mass flow rate of gas, resulted in tighter, more responsive control. The effect of a ratio change varied with different formulations and different slurry rates. Furthermore, changes in slurry rate caused complications, as the impact on particle size growth in the dryer is non-linear and difficult to predict. The cascade loop enables further study into the effect of particle size on detergent performance.

Radio-frequency slurry-density measurement for dredging pipelines

NARCIS (Netherlands)

van Eeten, M.J.C.

2011-01-01

Hydraulic dredgers make use of a density meter to measure the instantaneous density in the slurry transport pipeline, primarily for process control and production calculation. the current ‘golden’ standard for slurry density measurement is the radioactive density meter. It is based on a slurry

Non-aqueous slurries used as thickeners

Energy Technology Data Exchange (ETDEWEB)

Hatfield, J C

1982-04-07

A non-aqueous slurry is described that is suitable for use as a thickener or viscosifier in oil or gas drilling, fracturing, flow diversion completion or workover fluids. The slurry comprises a water-soluble cellulose ether polymer, a water-insoluble liquid hydrocarbon, a non-ionic surfactant having an HLB of from 7 to 14, and an organo modified clay. There also is described a process for thickening or viscosifying a drilling, fracturing, flow diversion, completion or workover fluid. The use of the slurry prevents bumping during addition to aqueous fluids. (27 claims)

An Evaluation of a Dual Coriolis Meter System for In-Line Monitoring of Suspended Solids Concentrations in Radioactive Slurries

International Nuclear Information System (INIS)

Hylton, T.D.

2000-01-01

The U.S. Department of Energy (DOE) has millions of gallons of radioactive liquid and sludge wastes stored in underground tanks at several of its sites. In order to comply with various regulations and to circumvent potential problems associated with tank integrity, these wastes must be retrieved from the tanks, transferred to treatment facilities (or other storage locations), and processed to stable waste forms. The sludge wastes will typically be mobilized by some mechanical means (e.g., mixer pump, submerged jet) and mixed with the respective supernatants to create slurries that can be transferred by pipeline to the desired destination. Depending on the DOE site, these slurries may be transferred up to six miles. Since the wastes are radioactive, it is critically important for the transfers to be made without plugging a pipeline. To reduce such a risk, the relevant properties of the slurry (e.g., density, suspended solids concentration, viscosity, and particle size distribution) should be determined to be within acceptable limits prior to transfer. These properties should also be continuously monitored and controlled within specified limits while the transfer is in progress. The baseline method for determining the transport properties of slurries involves sampling and analysis; however, this method is time-consuming, and costly, and it does not provide real-time information. In addition, personnel who collect and analyze the samples are exposed to radiation. It is also questionable as to whether a laboratory analyst can obtain representative aliquots from the sample jar for these solid-liquid mixtures. The alternative method for determining the transport properties is in-line analysis. An in-line instrument is one that is connected to the process, analyzes the slurry as it flows through or by the instrument, and provides the results within seconds. This instrument can provide immediate feedback to operators so that, when necessary, the operators can respond

Sorption of 17b-Estradiol to Pig Slurry Separates and Soil in the Soil-Slurry Environment

DEFF Research Database (Denmark)

Amin, Mostofa; Petersen, Søren O; Lægdsmand, Mette

2012-01-01

to agricultural soils, to different size fractions of pig slurry separates, and to soils amended with each size fraction to simulate conditions in the soil–slurry environment. A crude fiber fraction (SS1) was prepared by sieving (solids removed by an on-farm separation process. Three other size...... fractions (SS2 > SS3 > SS4) were prepared from the liquid fraction of the separated slurry by sedimentation and centrifugation. Sorption experiments were conducted in 0.01 mol L−1 CaCl2 and in natural pig urine matrix. Sorption in 0.01 mol L−1 CaCl2 was higher than that in pig urine for all solids used....... Sorption of E2 to soil increased with its organic carbon content for both liquid phases. The solid–liquid partition coefficients of slurry separates were 10 to 30 times higher than those of soils, but the organoic carbon normalized partition coefficient values, reflecting sorption per unit organic carbon...

Rheology of corn stover slurries during fermentation to ethanol

Science.gov (United States)

Ghosh, Sanchari; Epps, Brenden; Lynd, Lee

2017-11-01

In typical processes that convert cellulosic biomass into ethanol fuel, solubilization of the biomass is carried out by saccharolytic enzymes; however, these enzymes require an expensive pretreatment step to make the biomass accessible for solubilization (and subsequent fermentation). We have proposed a potentially-less-expensive approach using the bacterium Clostridium thermocellum, which can initiate fermentation without pretreatment. Moreover, we have proposed a ``cotreatment'' process, in which fermentation and mechanical milling occur alternately so as to achieve the highest ethanol yield for the least milling energy input. In order to inform the energetic requirements of cotreatment, we experimentally characterized the rheological properties of corn stover slurries at various stages of fermentation. Results show that a corn stover slurry is a yield stress fluid, with shear thinning behavior well described by a power law model. Viscosity decreases dramatically upon fermentation, controlling for variables such as solids concentration and particle size distribution. To the authors' knowledge, this is the first study to characterize the changes in the physical properties of biomass during fermentation by a thermophilic bacterium.

Rain scavenging of radioactive particles

International Nuclear Information System (INIS)

Williams, A.L.

1975-01-01

An assessment is made of the rainout of airborne radioactive particles from a nuclear detonation with emphasis on the microphysical removal processes. For submicron particles the scavenging processes examined are Brownian and turbulent diffusion to cloud droplets. For particles larger than 1 μm radius, nucleation scavenging is examined. For various particle size and radioactivity distributions, it is found that from 27 to 99 percent of the radioactivity is attached to cloud droplets and subject to rapid removal by rain. (U.S.)

Liquid CO₂/Coal Slurry for Feeding Low Rank Coal to Gasifiers

Energy Technology Data Exchange (ETDEWEB)

Marasigan, Jose [Electric Power Research Institute, Inc., Palo Alto, CA (United States); Goldstein, Harvey [Electric Power Research Institute, Inc., Palo Alto, CA (United States); Dooher, John [Electric Power Research Institute, Inc., Palo Alto, CA (United States)

2013-09-30

This study investigates the practicality of using a liquid CO₂/coal slurry preparation and feed system for the E-Gas™ gasifier in an integrated gasification combined cycle (IGCC) electric power generation plant configuration. Liquid CO₂ has several property differences from water that make it attractive for the coal slurries used in coal gasification-based power plants. First, the viscosity of liquid CO₂ is much lower than water. This means it should take less energy to pump liquid CO₂ through a pipe compared to water. This also means that a higher solids concentration can be fed to the gasifier, which should decrease the heat requirement needed to vaporize the slurry. Second, the heat of vaporization of liquid CO₂ is about 80% lower than water. This means that less heat from the gasification reactions is needed to vaporize the slurry. This should result in less oxygen needed to achieve a given gasifier temperature. And third, the surface tension of liquid CO₂ is about 2 orders of magnitude lower than water, which should result in finer atomization of the liquid CO₂ slurry, faster reaction times between the oxygen and coal particles, and better carbon conversion at the same gasifier temperature. EPRI and others have recognized the potential that liquid CO₂ has in improving the performance of an IGCC plant and have previously conducted systemslevel analyses to evaluate this concept. These past studies have shown that a significant increase in IGCC performance can be achieved with liquid CO₂ over water with certain gasifiers. Although these previous analyses had produced some positive results, they were still based on various assumptions for liquid CO₂/coal slurry properties.

Simulation of Reynolds number influence on heat exchange in turbulent flow of medium slurry

Science.gov (United States)

Bartosik, A.

2016-10-01

The paper deals with the numerical simulation of mass and heat exchange in turbulent flow of solid-liquid mixture in the range of averaged solid particle diameter from 0.10mm to 0.80mm, named further as the medium slurry. Physical model assumes that dispersed phase is fully suspended and a turbulent flow is hydro-dynamically, and thermally developed in a straight horizontal pipeline. Taking into account the aforementioned assumptions the slurry is treated as a single-phase flow with increased density, while viscosity is equals to a carrier liquid viscosity. The mathematical model constitutes time averaged momentum equation in which the turbulent stress tensor was designated using a two-equation turbulence model, which makes use of the Boussinesq eddy-viscosity hypothesis. Turbulence damping function in the turbulence model was especially designed for the medium slurry. In addition, an energy equation has been used in which a convective term was determined from the energy balance acting on a unit pipe length, assuming linear changes of temperature in main flow direction. Finally, the mathematical model of non-isothermal medium slurry flow comprises four partial differential equations, namely momentum and energy equations, equations of kinetic energy of turbulence and its dissipation rate. Four partial differential equations were solved by a finite difference scheme using own computer code. The objective of the paper is to examine the influence of Reynolds number on temperature profiles and Nusselt number in turbulent flow of medium slurry in the range of solids concentration from 0% to 30% by volume. The effect of influential factors on heat transfer between the pipe and slurry is analysed. The paper demonstrates substantial impact of Reynolds number and solids volume fraction on the Nusselt number. The results of numerical simulation are reviewed.

Method of transporting radioactive slurry-like wastes

Energy Technology Data Exchange (ETDEWEB)

Kamiya, K; Yusa, H; Sugimoto, Y

1975-06-30

The object is to prevent blockage of a transporting tube to positively and effectively transport radioactive slurry wastes. A method of transporting radioactive slurry-like wastes produced in an atomic power plant, wherein liquid wastes produced in the power plant are diluted to form into a driving liquid, by which said radioactive slurry-like wastes are transported within the pipe, and said driving liquid is recovered as the liquid waste.

Demonstration Of Mixing And Transferring Settling Cohesive Slurry Simulants In The AY-102 Tank

International Nuclear Information System (INIS)

Adamson, D.

2011-01-01

In support of Hanford's waste certification and delivery of tank waste to the Waste Treatment and Immobilization Plant (WTP), Savannah River National Laboratory (SRNL) was tasked by the Washington River Protection Solutions (WRPS) to evaluate the effectiveness of mixing and transferring tank waste in a Double Shell Tank (DST) to the WTP Receipt Tank. The work discussed in this report (Phase III) address the impacts cohesive simulants have on mixing and batch transfer performance. The objective of the demonstrations performed in Phase III was to determine the impact that cohesive particle interactions in the simulants have on tank mixing using 1/22 nd scale mixing system and batch transfer of seed particles. This testing is intended to provide supporting evidence to the assumption that Hanford Small Scale Mixing Demonstration (SSMD) testing in water is conservative. The batch transfers were made by pumping the simulants from the Mixing Demonstration Tank (MDT) to six Receipt Tanks (RTs), and the consistency in the amount of seed particles in each batch was compared. Tests were conducted with non-Newtonian cohesive simulants with Bingham yield stress ranging from 0.3 Pa to 7 Pa. Kaolin clay and 100 μm stainless steel seed particles were used for all the non-Newtonian simulants. To specifically determine the role of the yield stress on mixing and batch transfer, tests were conducted with a Newtonian mixture of glycerol and water with at viscosity of 6.2 cP that was selected to match the Bingham consistency (high shear rate viscosity) of the higher yield stress kaolin slurries. The water/glycerol mixtures used the same 100 μm stainless steel seed particles. For the transfer demonstrations in Phase III, the mixer jet pumps were operated either at 10.0 gpm (28 ft/s nozzle velocity, U o D=0.63 ft 2 /s) or 8.0 gpm (22.4 ft/s nozzle velocity, U o D=0.504 ft 2 /s). All batch transfers from the MDT to the RTs were made at 0.58 gpm (MDT suction velocity 3.95 ft/s). The

Synergistic effect of PLGA nanoparticles and submicron triglyceride droplets in enhancing the intestinal solubilisation of a lipophilic weak base.

Science.gov (United States)

Joyce, Paul; Prestidge, Clive A

2018-06-15

A novel hybrid microparticulate system composed of poly(lactic-co-glycolic) acid (PLGA) nanoparticles and submicron medium-chain triglyceride (MCT) droplets was fabricated to overcome the pH-dependent solubility and precipitation challenges associated with a model poorly water-soluble weak base, cinnarizine (CIN). Molecular CIN was confined within both the lipid and polymer phase of PLGA-lipid hybrid (PLH) and PLGA-lipid-mannitol hybrid (PLMH) particles, which offered significant biopharmaceutical advantages in comparison to the unformulated drug, submicron MCT droplets and PLGA nanoparticles. This was highlighted by a substantial reduction in the pH-induced precipitation during in vitro gastrointestinal two-step dissolution studies. A >2.5-fold solubilisation enhancement was observed for the composite particles during simulated intestinal conditions, compared to pure CIN. Furthermore, the drug solubilisation capacity during in vitro intestinal digesting conditions was ~2-2.5 times greater for PLMH particles compared to the precursor emulsion droplets and PLGA nanoparticles. The observations from this study indicate that a synergy exists between the degradation products of PLGA nanoparticles and lipid droplets, whereby the dual-phase release and dissolution mechanism of the hybrid particles aids in prolonging pH-provoked precipitation. Subsequently, the ability for PLGA polymers and oligomers to act as polymeric precipitation inhibitors has been highlighted for the first time. Copyright © 2018 Elsevier B.V. All rights reserved.

Micromagnetic simulations of submicron cobalt dots

International Nuclear Information System (INIS)

Parker, G. J.; Cerjan, C.

2000-01-01

Numerical simulations of submicron Co extruded elliptical dots were performed to illustrate the relative importance of different physical parameters on the switching behavior in the easy direction. Shape, size, magnetic moment magnitude, and the magnitude and distribution of the crystalline anisotropicity were varied. The simulation represents magnetostatic, exchange, and crystalline anisotropicity fields on a structured mesh using finite difference techniques. The smooth boundary of the dots is accurately represented by use of the embedded curve boundary method. Agreement with experimental hysteresis measurements of submicron dot arrays is obtained when an appropriate angular distribution of the grain anisotropicity axes is invoked. (c) 2000 American Institute of Physics

Combustion characteristics of a charcoal slurry in a direct injection diesel engine and the impact on the injection system performance

International Nuclear Information System (INIS)

Soloiu, Valentin; Lewis, Jeffery; Yoshihara, Yoshinobu; Nishiwaki, Kazuie

2011-01-01

the charcoal is thought to have a paramount role in helping the diffusion type combustion and diminishing the particulate matter formation. As the load was increased, the amount of time it took to notice a decline in engine efficiency decreased. This was due to the injector sticking open which was seen by a sharp increase in the exhaust temperature. The internal flow into the injector had the tendency to form deposits on the injector's seat that were critical to the functionality of the injector. In order to alleviate this problem, a reduced charcoal particle size together with a new injector design were produced resulting in stable engine efficiency at 50% load for a period of 90 min without injector sticking. Even with improvements, the needle's seat into the injector body showed an accelerated wear 4-8 times faster than that in normal operation with diesel fuel and this cannot be sustained for long operational cycles. The investigations have proven that the new charcoal-diesel slurry can produce adequate sprays and burn with very good results in a direct injection diesel engine. The critical aspect of operation is the internal flow into the injector with the tendency to form deposits and wear in the injector. -- Highlights: → Investigations have proven the slurry fuel produces adequate sprays and burns with promising results in a diesel engine. → Pyrolysis of wood was used for the production of charcoal, which was successfully emulsified with diesel oil resulting in low viscosity slurry fuel. → Less smoke produced using the slurry fuel, and the NO x emissions of slurry fuel were improved after injection timing optimization. → Reduced charcoal particle size and new injector design produced stable engine efficiency without injector sticking.

State of the art on phase change material slurries

International Nuclear Information System (INIS)

Youssef, Ziad; Delahaye, Anthony; Huang Li; Trinquet, François; Fournaison, Laurence; Pollerberg, Clemens; Doetsch, Christian

2013-01-01

Highlights: ► A bibliographic study on PCM slurries. ► Clathrate Hydrate slurry, Microencapsulated PCM Slurry, shape-stabilized PCM slurries and Phase Change Material Emulsions. ► Formation, thermo-physical, rheological, heat transfers properties and applications of these four PCS systems. ► The use of thermal energy storage and distribution based on PCM slurries can improve the refrigerating machine performances. - Abstract: The interest in using phase change slurry (PCS) media as thermal storage and heat transfer fluids is increasing and thus leading to an enhancement in the number of articles on the subject. In air-conditioning and refrigeration applications, PCS systems represent a pure benefit resulting in the increase of thermal energy storage capacity, high heat transfer characteristics and positive phase change temperatures which can occur under low pressures. Hence, they allow the increase of energy efficiency and reduce the quantity of thermal fluids. This review describes the formation, thermo-physical, rheological, heat transfer properties and applications of four PCS systems: Clathrate hydrate slurry (CHS), Microencapsulated Phase Change Materials Slurry (MPCMS), shape-stabilized PCM slurries (SPCMSs) and Phase Change Material Emulsions (PCMEs). It regroups a bibliographic summary of important information that can be very helpful when such systems are used. It also gives interesting and valuable insights on the choice of the most suitable PCS media for laboratory and industrial applications.

COMPUTATIONAL AND EXPERIMENTAL MODELING OF SLURRY BUBBLE COLUMN REACTORS

Energy Technology Data Exchange (ETDEWEB)

Paul C.K. Lam; Isaac K. Gamwo; Dimitri Gidaspow

2002-05-01

The objective of this study was to develop a predictive experimentally verified computational fluid dynamics (CFD) model for gas-liquid-solid flow. A three dimensional transient computer code for the coupled Navier-Stokes equations for each phase was developed and is appended in this report. The principal input into the model is the viscosity of the particulate phase which was determined from a measurement of the random kinetic energy of the 800 micron glass beads and a Brookfield viscometer. The details are presented in the attached paper titled ''CFD Simulation of Flow and Turbulence in a Slurry Bubble Column''. This phase of the work is in press in a referred journal (AIChE Journal, 2002) and was presented at the Fourth International Conference on Multiphase Flow (ICMF 2001) in New Orleans, May 27-June 1, 2001 (Paper No. 909). The computed time averaged particle velocities and concentrations agree with Particle Image Velocimetry (PIV) measurements of velocities and concentrations, obtained using a combination of gamma-ray and X-ray densitometers, in a slurry bubble column, operated in the bubbly-coalesced fluidization regime with continuous flow of water. Both the experiment and the simulation show a down-flow of particles in the center of the column and up-flow near the walls and nearly uniform particle concentration. Normal and shear Reynolds stresses were constructed from the computed instantaneous particle velocities. The PIV measurement and the simulation produced instantaneous particle velocities. The PIV measurement and the simulation produced similar nearly flat horizontal profiles of turbulent kinetic energy of particles. To better understand turbulence we studied fluidization in a liquid-solid bed. This work was also presented at the Fourth International Conference on Multiphase Flow (ICMF 2001, Paper No. 910). To understand turbulence in risers, measurements were done in the IIT riser with 530 micron glass beads using a PIV

Hydrodynamics of the continuously filtering slurry reactor. Influence of load of solids and particle size distribution.

NARCIS (Netherlands)

Huizenga, P.; Kuipers, J.A.M.; van Swaaij, Willibrordus Petrus Maria

1997-01-01

Internal filtration in slurry bubble columns offers a possible solution to the filtration problems related to this reactor type. The applicability of the concept has already been demonstrated at full-scale for waste water treatment. Theoretical description of internal filtration is lacking, however.

Hydrodynamics of the continuously filtering slurry reactor. Influence of load of solids and particle size distribution

NARCIS (Netherlands)

Huizenga, P.; Kuipers, J.A.M.; van Swaaij, W.P.M.

1997-01-01

Internal filtration in slurry bubble columns offers a possible solution to the filtration problems related to this reactor type. The applicability of the concept has already been demonstrated at full-scale for waste water treatment. Theoretical description of internal filtration is lacking, however.

Vectors and submicron precision: redundancy and 3D stacking in silicon pixel detectors

CERN Document Server

Heijne, E H M; Wong, W; Idarraga, J; Visser, J; Jakubek, J; Leroy, C; Turecek, D; Visschers, J; Pospisil, S; Ballabriga, R; Vykydal, Z; Vermeulen, J; Plackett, R; Heijne, E H M; Llopart, X; Boltje, D; Campbell, M

2010-01-01

Measurements are shown of GeV pions and muons in two 300 mu m thick, Si Medipix pixel detector assemblies that are stacked on top of each other, with a 25 mu m thick brass foil in between. In such a radiation imaging semiconductor matrix with a large number of pixels along the particle trail, one can determine local space vectors for the particle trajectory instead of points. This improves pattern recognition and track reconstruction, especially in a crowded environment. Stacking of sensor planes is essential for resolving directional ambiguities. Signal charge sharing can be employed for measuring positions with submicron precision. In the measurements one notices accompanying `delta' electrons that emerge outside the particle trail, far beyond the boundaries of the 55 mu m pixel cells. The frequency of such corrupted position measurements is similar to one per 2.5mm of traversed Si.

Detecting Poor Cement Bonding and Zonal Isolation Problems Using Magnetic Cement Slurries

KAUST Repository

Nair, Sriramya D.; Patzek, Tadeusz; van Oort, Eric

2017-01-01

There has been growing interest in the use of magnetorheological fluids to improve displacement efficiency of fluids (drilling fluids, spacer fluids, cement slurries) in the eccentric casing annuli. When magnetic particles are mixed with the cement slurry for improved displacement, they provide an excellent opportunity for sensing the presence and quality of cement in the annulus. This work focuses on using sophisticated 3D computational electromagnetics to simulate the use of a magnetic cement slurry for well cement monitoring. The main goal is to develop a new tool, which is capable of locating magnetic cement slurry that is placed behind a stainless steel casing. An electromagnetic coil was used to generate a magnetic field inside the borehole. It was found that when a current was passed through the electric coils, magnetic field lines passed through the stainless steel casing, the cement annulus and the rock formation. Three sensors were placed inside the cased borehole and the magnetic field strength variations were observed at these locations. Various factors that have a significant influence on zonal isolation were considered. These include, effect of debonding between casing and cement annulus, effect of changing annuli thickness, influence of a fracture in the rock formation, effect of changing magnetic permeability of cement and finally influence of annuli eccentricity. Based on the results shown in the paper along with the next generation of supersensitive magnetic sensors that are being developed, the magnetic approach appears to be a viable alternative for evaluating the quality of the cement annulus to ensure good zonal isolation.

Detecting Poor Cement Bonding and Zonal Isolation Problems Using Magnetic Cement Slurries

KAUST Repository

Nair, Sriramya D.

2017-10-02

There has been growing interest in the use of magnetorheological fluids to improve displacement efficiency of fluids (drilling fluids, spacer fluids, cement slurries) in the eccentric casing annuli. When magnetic particles are mixed with the cement slurry for improved displacement, they provide an excellent opportunity for sensing the presence and quality of cement in the annulus. This work focuses on using sophisticated 3D computational electromagnetics to simulate the use of a magnetic cement slurry for well cement monitoring. The main goal is to develop a new tool, which is capable of locating magnetic cement slurry that is placed behind a stainless steel casing. An electromagnetic coil was used to generate a magnetic field inside the borehole. It was found that when a current was passed through the electric coils, magnetic field lines passed through the stainless steel casing, the cement annulus and the rock formation. Three sensors were placed inside the cased borehole and the magnetic field strength variations were observed at these locations. Various factors that have a significant influence on zonal isolation were considered. These include, effect of debonding between casing and cement annulus, effect of changing annuli thickness, influence of a fracture in the rock formation, effect of changing magnetic permeability of cement and finally influence of annuli eccentricity. Based on the results shown in the paper along with the next generation of supersensitive magnetic sensors that are being developed, the magnetic approach appears to be a viable alternative for evaluating the quality of the cement annulus to ensure good zonal isolation.

A methodology to predict the uniformity of double-shell waste slurries based on mixer pump operation

International Nuclear Information System (INIS)

Liljegren, L.M.; Bamberger, J.A.

1992-08-01

Dimensional analysis is used to determine the similarity parameters that describe the uniformity of radioactive slurry wastes to be suspended by mixer pumps. The results of this analysis are applied to the design of scaled experiments that will determine the operating parameters that will ensure an adequately uniform feed stream during waste retrieval from Hanford double-shell tanks. Ten dimensionless parameters describing the slurry mixing process were identified. Of these, three describe purely geometric features, three describe slurry properties only, one is a dimensionless time scale, and three describe important dynamic factors. The three parameters describing the dynamic features are the Reynolds number, which describes the degree of turbulence in the tank; the Froude number, which describes the effects of stratification on the circulation patterns; and the gravitational settling number, which describes the balance between the work done by gravity to cause settling and the work done by the pump to resuspend particles

Synthesis and characterization of hollow α-Fe2O3 sub-micron spheres prepared by sol–gel

International Nuclear Information System (INIS)

León, Lizbet; Bustamante, Angel; Osorio, Ana; Olarte, G. S.; Santos Valladares, Luis De Los; Barnes, Crispin H. W.; Majima, Yutaka

2011-01-01

In this work we report the preparation of magnetic hematite hollow sub-micron spheres (α-Fe 2 O 3 ) by colloidal suspensions of ferric nitrate nine-hydrate (Fe(NO 3 ) 3 ·9H 2 O) particles in citric acid solution by following the sol–gel method. After the gel formation, the samples were annealed at different temperatures in an oxidizing atmosphere. Annealing at 180°C resulted in an amorphous phase, without iron oxide formation. Annealing at 250°C resulted in coexisting phases of hematite, maghemite and magnetite, whereas at 400°C, only hematite and maghemite were found. Pure hematite hollow sub-micron spheres with porous shells were formed after annealing at 600°C. The characterization was performed by X-ray diffraction (XRD), Mössbauer spectroscopy (MS) and scanning electron microscopy (SEM).

The effects of synthesis parameters on the formation of PbI2 particles under DTAB-assisted hydrothermal process

International Nuclear Information System (INIS)

Zhu Gangqiang; Hojamberdiev, Mirabbos; Liu Peng; Peng Jianhong; Zhou Jianping; Bian Xiaobin; Huang Xijin

2011-01-01

Highlights: ► Submicron- and micron-sized PbI 2 particles were hydrothermally synthesized. ► Structural transformation form belt-like to rod- and microtube-like was observed. ► Phase-pure PbI 2 particles could be hydrothermally obtained at pH 2 particles. ► The optical band gap energy of PbI 2 was slightly affected by morphology. - Abstract: Submicron- and micron-sized lead iodide (PbI 2 ) particles with well-controlled morphologies were successfully fabricated via a low-temperature hydrothermal process assisted by dodecyltrimethylammonium bromide (DTAB) as cationic surfactant. The as-synthesized powders were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and UV–vis spectroscopy. The effects of synthesis parameters (temperature, time, pH, and surfactant amount) were systematically investigated. The obtained results showed that the submicron structure was belt-like at 100–120 °C, transformed to rod-like by increasing temperature to 140 °C and it became a microtube-like at 160–200 °C. By changing the pH of the synthesizing solution, it was found that a pure PbI 2 phase could be obtained below 7. With the addition of increasing amount of surfactant, microparticles were converted to microrods → submicron belts → microtubes. The time-dependent experimental results revealed that the dissolution–recrystallization and dissolution–recrystallization–self-oriented-attachment were considered to be the possible mechanisms for the formation of the belt- and tube-like PbI 2 submicron- and micron-sized particles, respectively. The optical properties of the PbI 2 particles synthesized at 100–200 °C for 8 h under hydrothermal conditions were also studied.

Protozoan predation in soil slurries compromises determination of contaminant mineralization potential

International Nuclear Information System (INIS)

Badawi, Nora; Johnsen, Anders R.; Brandt, Kristian K.; Sørensen, Jan; Aamand, Jens

2012-01-01

Soil suspensions (slurries) are commonly used to estimate the potential of soil microbial communities to mineralize organic contaminants. The preparation of soil slurries disrupts soil structure, however, potentially affecting both the bacterial populations and their protozoan predators. We studied the importance of this “slurry effect” on mineralization of the herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA, 14 C-labelled), focussing on the effects of protozoan predation. Mineralization of MCPA was studied in “intact” soil and soil slurries differing in soil:water ratio, both in the presence and absence of the protozoan activity inhibitor cycloheximide. Protozoan predation inhibited mineralization in dense slurry of subsoil (soil:water ratio 1:3), but only in the most dilute slurry of topsoil (soil:water ratio 1:100). Our results demonstrate that protozoan predation in soil slurries may compromise quantification of contaminant mineralization potential, especially when the initial density of degrader bacteria is low and their growth is controlled by predation during the incubation period. - Highlights: ► We studied the protozoan impact on MCPA mineralization in soil slurries. ► Cycloheximide was used as protozoan inhibitor. ► Protozoa inhibited MCPA mineralization in dilute topsoil slurry and subsoil slurry. ► Mineralization potentials may be underestimated when using soil slurries. - Protozoan predation may strongly bias the quantification of mineralization potential when performed in soil slurries, especially when the initial density of degrader bacteria is low such as in subsoil or very dilute topsoil slurries.

Effectiveness of reinforcement incorporation and mechanical properties of composites produced from rheocast slurries

Energy Technology Data Exchange (ETDEWEB)

Robert, M.H.; Galvao da Silveira Mussi, R. [Faculty of Mechanical Engineering, State Univ. of Campinas, Cidade Univ. (Brazil)

2002-07-01

The influence of compocasting variables (SiC size and %vol, additions of grain refiner and extra Mg) in the quality of A356+SiCp MMCs is investigated. In all conditions microstructures show Al-{alpha} with globular morphology with eutectic and SiC in interglobular regions. Results show tendency of agglomeration of thinner particles, jeopardising their incorporation and dispersion in the matrix; high quantities of SiC are not incorporated into rheocast slurries with refined globules, grain refinement decreases incorporation of bigger particles. Extra Mg does not influence incorporation. Best results are obtained for 15% vol of 30 {mu}m SiC added to grain refined matrix. Mechanical properties are poor when agglomeration of particles is present. (orig.)

Effect of slurries density on the properties of ceramic foam produced via polymer replication method

International Nuclear Information System (INIS)

Mohd Al Amin Muhammad Nor; Lee Chain Hong; Hazizan Md Akil; Zainal Ariffin Ahmad

2007-01-01

Ceramic foams are a class of high porosity materials that are used or being considered for a wide range of technological applications. Ceramic foam was produce by polymer replication method. In this process, commercial polymeric sponge was use as template, dipping with ceramic particles slurry, drying and then sintered to yield a replica of the original foams. The study was focus on the fabrication of different density of ceramic foams by varying the density of ceramic slurries (1.1876, 1.2687, 1.3653 and 1.5295 g/cm?3). Properties of ceramic foam produced such as density was characterized accordingly to ASTM C 271-94 and porosity were characterized using Archimedes methods. Compressive and bending strength was performed accordingly to ASTM C1161-94 and C773-88 (1999), respectively. The morphological study was performed using Scanning Electron Microscopy (SEM) and EDX. Density of ceramic foams produced was about 0.5588 and 1.1852 g/cm 3 , where as porosity was around 26.28 and 70.59 %. Compressive and bending strength was increase from strength also increases from 2.60 to 23.07 MPa and 1.20 to 11.10 MPa, respectively, with increasing of slurries density from 1.1876 to 1.3653 g/cm 3 . The SEM micrographs show that the cells structure become denser as the slurries density increased. EDX proved that the ceramic used is porcelain. As conclusion, increasing in slurries density produced ceramic foams with good mechanical properties such as compressive and bending strength and denser body. (Author)

PROGRESS TOWARDS MODELING OF FISCHER TROPSCH SYNTHESIS IN A SLURRY BUBBLE COLUMN REACTOR

Energy Technology Data Exchange (ETDEWEB)

Donna Post Guillen; Tami Grimmett; Anastasia M. Gandrik; Steven P. Antal

2010-11-01

The Hybrid Energy Systems Testing (HYTEST) Laboratory is being established at the Idaho National Laboratory to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. A central component of the HYTEST is the slurry bubble column reactor (SBCR) in which the gas-to-liquid reactions will be performed to synthesize transportation fuels using the Fischer Tropsch (FT) process. SBCRs are cylindrical vessels in which gaseous reactants (for example, synthesis gas or syngas) is sparged into a slurry of liquid reaction products and finely dispersed catalyst particles. The catalyst particles are suspended in the slurry by the rising gas bubbles and serve to promote the chemical reaction that converts syngas to a spectrum of longer chain hydrocarbon products, which can be upgraded to gasoline, diesel or jet fuel. These SBCRs operate in the churn-turbulent flow regime which is characterized by complex hydrodynamics, coupled with reacting flow chemistry and heat transfer, that effect reactor performance. The purpose of this work is to develop a computational multiphase fluid dynamic (CMFD) model to aid in understanding the physico-chemical processes occurring in the SBCR. Our team is developing a robust methodology to couple reaction kinetics and mass transfer into a four-field model (consisting of the bulk liquid, small bubbles, large bubbles and solid catalyst particles) that includes twelve species: (1) CO reactant, (2) H2 reactant, (3) hydrocarbon product, and (4) H2O product in small bubbles, large bubbles, and the bulk fluid. Properties of the hydrocarbon product were specified by vapor liquid equilibrium calculations. The absorption and kinetic models, specifically changes in species concentrations, have been incorporated into the mass continuity equation. The reaction rate is determined based on the macrokinetic model for a cobalt catalyst developed by Yates and Satterfield [1]. The

Formation and filtration of flocs from coal slurries

Energy Technology Data Exchange (ETDEWEB)

Singh, B K

1977-06-01

The size and size distribution of flocs are greatly influenced by the type and concentration of the flocculant coal and dirt particles behave differently in this respect. The pH and the concentration of electrolytes also influence flocculation, by changing both the surface properties of the solid material and the effectiveness of the flocculant. The relationship between the sedimentation time and the filtration rate depends on the concentration and type of flocculant. Optimum pH values for various conditions are tabulated. When an anion-active flocculant is added to a coal-dirt mixture in an alkaline medium, selective flocculation occurs; this can be used to improve the separation of slurries.

Design and characterization of submicron formulation for a poorly soluble drug: the effect of Vitamin E TPGS and other solubilizers on skin permeability enhancement.

Science.gov (United States)

Ghosh, Indrajit; Michniak-Kohn, Bozena

2012-09-15

In transdermal drug delivery systems (TDDS), it is a challenge to achieve stable and prolonged high permeation rates across the skin since the concentrations of the drug dissolved in the matrix have to be high in order to maintain zero order release kinetics. Several attempts have been reported to improve the permeability of poorly soluble drug compounds using supersaturated systems, however, due to thermodynamic challenges, there was a high tendency for the drug to nucleate immediately after formulating or even during storage. The present study focuses on the efficiency of drug crystals at the submicron/nano range in presence of different solubilizers to improve the permeation rate. Effect of several solubilizers, e.g. Pluronic F-127, Vitamin E TPGS, propylene glycol were studied on the submicron suspension systems of ibuprofen as a model drug. Various stabilizers such as hydroxylpropyl methylcellulose (HPMC) and polyvinylpyrrolidone (PVP) were examined to evaluate their crystal inhibitory effects on particle growth of the drug compound at submicron range. The overall permeation enhancement process through the skin seems to be influenced by the presence of solubilizers and also the presence of submicron drug crystal. The most promising stable formulation was developed with Vitamin E TPGS+HPMC submicron suspension, which produced higher permeation rate compared to other vehicles. Copyright © 2012 Elsevier B.V. All rights reserved.

Life Cycle Assessment of Slurry Management Technologies

DEFF Research Database (Denmark)

Wesnæs, Marianne; Wenzel, Henrik; Petersen, Bjørn Molt

This report contains the results of Life Cycle Assessments of two slurry management technologies - acidification and decentred incineration. The LCA foundation can be used by the contributing companies for evaluating the environmental sustainability of a specific technology from a holistic Life...... Cycle perspective. Through this the companies can evaluate the environmental benefits and disadvantages of introducing a specific technology for slurry management. From a societal perspective the results can contribute to a clarification of which slurry management technologies (or combination...... of technologies) having the largest potential for reducing the overall environmental impacts....

Feasibility studies of the on-stream analysis of lead in mineral slurries

International Nuclear Information System (INIS)

Kawatra, S.K.

1976-01-01

Instruments for the measurement of lead in mineral slurries by the use of isotopes can be based on the absorption of low-energy gamma rays, backscattering of beta particles, or X-ray fluorescence. The merits of each method are discussed, and the reasons for the selection of the beta-backscattering technique are given. A system using this technique has been designed, constructed, and tested on samples of concentrates from an industrial concentrator [af

Availability of phosphorus in cow slurry using isotopic labelling technique

International Nuclear Information System (INIS)

Pongsakul, P.; Bertelsen, F.; Gissel-Nielsen, G.

1988-01-01

A pot experiment was conducted to evaluate the influence of cow slurry on P uptake by corn and to estimate the readily available P in the slurry by using an isotopic labelling techique. Water-soluble P in soil was increased and isotopic equilibrium of available P was attained after labelled slurry was mixed thoroughly throughout the soil. Labelled slurry applied at planting increased the P uptake by corn, whereas the same amount applied one week before harvest did not affect the P uptake. It was estimated that 46-54% of the total P uptake in plants is derived from the slurry. The readily available P (the L-value) in the slurry was at least 26 mg/kg which equals 3.7% of the total P. (author)

Ice slurry flow and heat transfer during flow through tubes of rectangular and slit cross-sections

Directory of Open Access Journals (Sweden)

Niezgoda-Żelasko Beata

2014-09-01

Full Text Available The paper presents the results of experimental research of pressure drop and heat transfer coefficients of ice slurry during its flow through tubes of rectangular and slit cross-sections. Moreover, the work discusses the influence of solid particles, type of motion and cross-section on the changes in the pressure drop and heat transfer coefficient. The analysis presented in the paper allows for identification of the criterial relations used to calculate the Fanning factor and the Nusselt number for laminar and turbulent flow, taking into account elements such as phase change, which accompanies the heat transfer process. Ice slurry flow is treated as a generalized flow of a non-Newtonian fluid.

Rheological properties of defense waste slurries

International Nuclear Information System (INIS)

Ebadian, M.A.

1998-01-01

The major objective of this two-year project has been to obtain refined and reliable experimental data about the rheological properties of melter feeds. The research has involved both experimental studies and model development. Two experimental facilities have been set up to measure viscosity and pressure drop. Mathematical models have been developed as a result of experimental observation and fundamental rheological theory. The model has the capability to predict the viscosity of melter slurries in a range of experimental conditions. The final results of the investigation could be used to enhance the current design base for slurry transportation systems and improve the performance of the slurry mixing process. If successful, the cost of this waste treatment will be reduced, and disposal safety will be increased. The specific objectives for this project included: (1) the design, implementation, and validation of the experimental facility in both batch and continuous operating modes; (2) the identification and preparation of melter feed samples of both the SRS and Hanford waste slurries at multiple solids concentration levels; (3) the measurement and analysis of the melter feeds to determine the effects of the solids concentration, pH value, and other factors on the rheological properties of the slurries; (4) the correlation of the rheological properties as a function of the measured physical and chemical parameters; and (5) transmission of the experimental data and resulting correlation to the DOE site user to guide melter feed preparation and transport equipment design

Rheological Characterization of Unusual DWPF Slurry Samples

International Nuclear Information System (INIS)

Koopman, D. C.

2005-01-01

A study was undertaken to identify and clarify examples of unusual rheological behavior in Defense Waste Processing Facility (DWPF) simulant slurry samples. Identification was accomplished by reviewing sludge, Sludge Receipt and Adjustment Tank (SRAT) product, and Slurry Mix Evaporator (SME) product simulant rheological results from the prior year. Clarification of unusual rheological behavior was achieved by developing and implementing new measurement techniques. Development of these new methods is covered in a separate report, WSRC-TR-2004-00334. This report includes a review of recent literature on unusual rheological behavior, followed by a summary of the rheological measurement results obtained on a set of unusual simulant samples. Shifts in rheological behavior of slurries as the wt. % total solids changed have been observed in numerous systems. The main finding of the experimental work was that the various unusual DWPF simulant slurry samples exhibit some degree of time dependent behavior. When a given shear rate is applied to a sample, the apparent viscosity of the slurry changes with time rather than remaining constant. These unusual simulant samples are more rheologically complex than Newtonian liquids or more simple slurries, neither of which shows significant time dependence. The study concludes that the unusual rheological behavior that has been observed is being caused by time dependent rheological properties in the slurries being measured. Most of the changes are due to the effect of time under shear, but SB3 SME products were also changing properties while stored in sample bottles. The most likely source of this shear-related time dependence for sludge is in the simulant preparation. More than a single source of time dependence was inferred for the simulant SME product slurries based on the range of phenomena observed. Rheological property changes were observed on the time-scale of a single measurement (minutes) as well as on a time scale of hours

Facile synthesis and stable cycling ability of hollow submicron silicon oxide–carbon composite anode material for Li-ion battery

Energy Technology Data Exchange (ETDEWEB)

Kim, Joong-Yeon; Nguyen, Dan Thien [Department of Fine Chemical Engineering & Applied Chemistry, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Kang, Joon-Sup [Department of Energy Science and Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Song, Seung-Wan, E-mail: swsong@cnu.ac.kr [Department of Fine Chemical Engineering & Applied Chemistry, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Department of Energy Science and Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

2015-06-05

Highlights: • Hollow submicron SiO{sub 2}–carbon composite material was synthesized using Si{sup 4+}-citrate chelation. • Composite material possessed a homogeneous distribution of SiO{sub 2} and carbon. • Composite electrode delivered ⩾600 mAh/g with a stable cycling stability. • This materials design and synthesis provides a useful platform for scalable production. - Abstract: Advanced SiO{sub 2}–carbon composite anode active material for lithium-ion battery has been synthesized through a simple chelation of silicon cation with citrate in a glyme-based solvent. The resultant composite material demonstrates a homogeneous distribution of constituents over the submicron particles and a unique hollow spherical microstructure, which provides an enhanced electrical conductivity and better accommodation of volume change of silicon during electrochemical charge–discharge cycling, respectively. As a result, the composite electrode exhibits a high cycling stability delivering the capacity retention of 91% at the 100th cycle and discharge capacities of 662–602 mAh/g and coulombic efficiencies of 99.8%. This material synthesis is scalable and cost-effective in preparing various submicron or micron composite electrode materials.

System and method for continuous solids slurry depressurization

Science.gov (United States)

Leininger, Thomas Frederick; Steele, Raymond Douglas; Cordes, Stephen Michael

2017-07-11

A system includes a first pump having a first outlet and a first inlet, and a controller. The first pump is configured to continuously receive a flow of a slurry into the first outlet at a first pressure and to continuously discharge the flow of the slurry from the first inlet at a second pressure less than the first pressure. The controller is configured to control a first speed of the first pump against the flow of the slurry based at least in part on the first pressure, wherein the first speed of the first pump is configured to resist a backflow of the slurry from the first outlet to the first inlet.

Co-formation of hydroperoxides and ultra-fine particles during the reactions of ozone with a complex VOC mixture under simulated indoor conditions

DEFF Research Database (Denmark)

Fan, Z.H.; Weschler, Charles J.; Han, IK

2005-01-01

In this study we examined the co-formation of hydrogen peroxide and other hydroperoxides (collectively presented as H2O2*) as well as submicron particles, including ultra-fine particles (UFP), resulting from the reactions of ozone (O-3) with a complex mixture of volatile organic compounds (VOCs...... higher than typical indoor levels. When O-3 was added to a 25-m(3) controlled environmental facility (CEF) containing the 23 VOC mixture, both H2O2* and submicron particles were formed. The 2-h average concentration of H2O2* was 1.89 +/- 0.30ppb, and the average total particle number concentration was 46...... to achieve saturated concentrations of the condensable organics. When the 2 terpenes were removed from the O-3/23 VOCs mixture, no H2O2* or particles were formed, indicating that the reactions of O-3 With the two terpenes were the key processes contributing to the formation of H2O2* and submicron particles...

Viability of Ascaris suum eggs in stored raw and separated liquid slurry

DEFF Research Database (Denmark)

Katakam, Kiran Kumar; Roepstorff, Allan Knud; Popovic, Olga

2013-01-01

SUMMARY Separation of pig slurry into solid and liquid fractions is gaining importance as a way to manage increasing volumes of slurry. In contrast to solid manure and slurry, little is known about pathogen survival in separated liquid slurry. The viability of Ascaris suum eggs, a conservative...... indicator of fecal pollution, and its association with ammonia was investigated in separated liquid slurry in comparison with raw slurry. For this purpose nylon bags with 6000 eggs each were placed in 1 litre bottles containing one of the two fractions for 308 days at 5 °C or 25 °C. Initial analysis...... of helminth eggs in the separated liquid slurry revealed 47 Ascaris eggs per gramme. At 25 °C, egg viability declined to zero with a similar trend in both raw slurry and the separated liquid slurry by day 308, a time when at 5 °C 88% and 42% of the eggs were still viable in separated liquid slurry and raw...

A Novel Submicron Emulsion System Loaded with Doxorubicin Overcome Multi-Drug Resistance in MCF-7/ADR Cells.

Science.gov (United States)

Zhou, W P; Hua, H Y; Sun, P C; Zhao, Y X

2015-01-01

The purpose of the present study was to develop the Solutol HS15-based doxorubicin submicron emulsion with good stability and overcoming multi-drug resistance. In this study, we prepared doxorubicin submicron emulsion, and examined the stability after autoclaving, the in vitro cytotoxic activity, the intracellular accumulation and apoptpsis of doxorubicin submicron emulsion in MCF-7/ADR cells. The physicochemical properties of doxorubicin submicron emulsion were not significantly affected after autoclaving. The doxorubicin submicron emulsion significantly increased the intracellular accumulation of doxorubicin submicron emulsion and enhanced cytotoxic activity and apoptotic effects of doxorubicin. These results may be correlated to doxorubicin submicron emulsion inhibitory effects on efflux pumps through the progressive release of intracellular free Solutol HS15 from doxorubicin submicron emulsion. Furthermore, these in vitro results suggest that the Solutol HS15-based submicron emulsion may be a potentially useful drug delivery system to circumvent multi-drug resistance of tumor cells.

Rotary drum dryers for coal slurries

Energy Technology Data Exchange (ETDEWEB)

Baunack, F

1983-04-01

The suitability, sizing and internal equipment of rotary drum dryers for high-ash coal slurries are discussed. Rotary dryers will handle also difficult slurries; by suitable drum sizes, lifter blades and chains not only high specific evaporation capacities can be achieved but also very high throughputs of up to 400 tons/h of finished product and high evaporation capacities of 60 tons/h.

Aerosol particles in the Mexican East Pacific Part I: processing and vertical redistribution by clouds

Directory of Open Access Journals (Sweden)

D. Baumgardner

2005-01-01

Full Text Available Airborne measurements of aerosol particle size distributions were made in the Mexican Intertropical Convergence Zone. The volume concentrations of submicron and super micron particles at cloud base were compared with those in near-cloud regions over a range of altitudes. Of 78 near-cloud regions analyzed, 68% and 45% had enhanced volumes of submicron particles and supermicron particles, respectively. In addition, 35% of these regions had supermicron particles removed, presumably by precipitation. In 61% of the cases the enhancement in volume occurred over the size range from 0.1 to 50 μm whereas only submicron volumes were enhanced in 35% of the cases. In regions near clouds that were formed in air of maritime origin the frequency of volume enhancement decreased with increasing altitude and was twice as frequent on the dissipating side of clouds compared to the growing side. No such differences were found in the regions near clouds formed in air originating from the land. The frequency and average magnitude of volume enhancement are in qualitative and quantitative agreement with previous observational and theoretical studies that relate enhancements in particle mass to the uptake by cloud droplets of SO2 accompanied by additional growth by droplet coalescence.

Effects of types of ventilation system on indoor particle concentrations in residential buildings.

Science.gov (United States)

Park, J S; Jee, N-Y; Jeong, J-W

2014-12-01

The objective of this study was to quantify the influence of ventilation systems on indoor particle concentrations in residential buildings. Fifteen occupied, single-family apartments were selected from three sites. The three sites have three different ventilation systems: unbalanced mechanical ventilation, balanced mechanical ventilation, and natural ventilation. Field measurements were conducted between April and June 2012, when outdoor air temperatures were comfortable. Number concentrations of particles, PM2.5 and CO2 , were continuously measured both outdoors and indoors. In the apartments with natural ventilation, I/O ratios of particle number concentrations ranged from 0.56 to 0.72 for submicron particles, and from 0.25 to 0.60 for particles larger than 1.0 μm. The daily average indoor particle concentration decreased to 50% below the outdoor level for submicron particles and 25% below the outdoor level for fine particles, when the apartments were mechanically ventilated. The two mechanical ventilation systems reduced the I/O ratios by 26% for submicron particles and 65% for fine particles compared with the natural ventilation. These results showed that mechanical ventilation can reduce exposure to outdoor particles in residential buildings. Results of this study confirm that mechanical ventilation with filtration can significantly reduce indoor particle levels compared with natural ventilation. The I/O ratios of particles substantially varied at the naturally ventilated apartments because of the influence of variable window opening conditions and unsteadiness of wind flow on the penetration of outdoor air particles. For better prediction of the exposure to outdoor particles in naturally ventilated residential buildings, it is important to understand the penetration of outdoor particles with variable window opening conditions. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Multi-element determinations of N,N-dimethylformamide (DMF) coal slurries using ICP-OES

Energy Technology Data Exchange (ETDEWEB)

M. Mujuru; R.I. McCrindle; B.M. Botha; P.P. Ndibewu [Tshwane University of Technology, Pretoria (South Africa). Department of Chemistry

2009-04-15

A slurry nebulisation technique was applied for elemental analysis of bituminous coals SARM 18, SARM 19 and four coals from three different seams in Witbank, South Africa, by inductively coupled plasma optical emission spectroscopy (ICP-OES). Major elements (Al, Ca, Fe, Mg, S, Si and Ti) and trace elements (Ba, Cr, Mn, Ni, Sr, V, Zn and Zr) in coal were determined. Various slurry preparations were evaluated using two dispersants (glycerol and Triton X-100) and by varying the concentration of dispersants, between 0.1% and 1.0% (v/v). The effect of initially solubilising the ground coal in N,N-dimethylformamide (DMF) was investigated by varying the volume of DMF added. The effect of wet grinding with DMF was investigated. Wet grinding with DMF was shown to drastically reduce particle sizes (50.0% < 0.28 m and 90.0% < 6.17 {mu}m) as compared to dry grinding (50.0% < 5.25 {mu}m and 90.0% < 11.1 {mu}m). The reduced particle sizes and increased transport efficiency of the coal slurries led to improved analytical recoveries of elements in the reference coal, SARM 18. The best analytical recoveries for all elements were achieved using 0.1% Triton X-100 with 10.0% DMF. Results obtained by ICP-OES after wet grinding of the coal with DMF, using 0.1% Triton X-100, also gave excellent recoveries (Al, 100%; Ca, 103%; Cr, 106%; Fe, 102%; Mg, 100%; Mn, 104%; Ni, 109%; Si, 102%; Ti, 95.0%; and V, 108%). The results obtained with 10.0% DMF and 0.1% Triton X-100 were in agreement with certified values for all selected elements according to paired t-test at the 95.0% confidence level. Selected elements (Al, Ca, Fe, Mg, Mn, Si, Ti and V) were also analysed with X-ray fluorescence for comparison with results obtained from ICP-OES. Analysis by ICP-OES of microwave digested coal was also carried out. It is suggested that the DMF slurry technique could be used for routine analysis of bituminous coals. 27 refs., 4 figs., 4 tabs.

Slurry growth: the characterization of a unique phenomenon at the Hanford Site

International Nuclear Information System (INIS)

Jansky, M.T.

1985-01-01

Slurry growth, unique to the Hanford Site, is a significant increase in the volume of waste contained in a waste storage tank without the addition of new waste. Slurry growth is caused by gas entrapment within waste slurries which causes the slurry to swell, like bread dough. The surface of the slurry rises until either gas pressure is great enough or the weight of the slurry over the gases is great enough to cause the surface of the slurry to collapse. The gases causing slurry growth are generated from decomposition of organics present in high-level nuclear waste (HEDTA, EDTA, GLY). Predominant gases are H 2 , N 2 , N 2 O, NO/sub x/, and CO 2 . More gas is generated, and at a faster rate, as the temperature increases. Slurry growth, although not completely eliminated, is being safely and effectively controlled. The parameters affecting slurry growth have been defined, and predictive equations have been established. The knowledge gained through laboratory experiments contributes to continued safe and efficient high-level waste management practices at the Hanford Site

Deposition of magnetite particles from high velocity water onto isothermal tubes

International Nuclear Information System (INIS)

Burrill, K.A.

1977-02-01

The deposition rate of magnetite particles from a high velocity water slurry onto isothermal metal tubes was measured. The effects of velocity (5 to 100 m/s), slurry concentration (200 to 1000 mg Fe/kg H 2 O), temperature (25 0 to 90 0 C), pH (4 to 10 at 25 0 C), and tube material (nickel, Zircaloy-4) on deposition rate were studied. The data are interpreted in terms of two steps in series for deposition: a mass transfer step followed by a deposition or inertial coasting step. Mass transfer of particles through the bulk water phase apparently limits the deposition of particles at high Reynolds number

Visualizing test on the pass-through and collision characteristics of coarse particles in a double blade pump

Directory of Open Access Journals (Sweden)

Minggao Tan

2018-01-01

Full Text Available As the key equipment in deep ocean mining, the slurry pump suffers from wear and blocking problems. In this paper, high-speed photography technique is applied to track the movement rule of single particle of the coarse particle solid–liquid two-phase flow in a double blade slurry pump. The influences of particle diameter and particle density on the pass-through and collision characteristics of particles are analyzed as well. The results show that the average of the passing pump time first decreases and then increases when the particle diameter increases. The average of the passing pump time decreases by 22.7%, when the particle density increases from 1.09 g/cm3 to 1.75 g/cm3. Besides, the particle density has great influence on the location where the particle hits the tongue. Most particles of 1.09 g/cm3 hit the tongue on the left side, while collision location of particles of 1.75 g/cm3 is mainly on the top and at the right side of the tongue. The research can provide a basis for the optimization design of slurry pump in deep ocean mining system.

Physical properties, fuel characteristics and P-fertilizer production related to animal slurry and products from separation of animal slurry

DEFF Research Database (Denmark)

Thygesen, Ole; Johnsen, Tina; Triolo, Jin Mi

The purpose of this study was twofold: firstly to examine the relationship between dry matter content (DM) and specific gravity (SG) and viscosity in slurry and the liquid fraction from slurry separation, and secondly to investigate the potential of energy production from combustion of manure fibre...... from slurry separation and phosphorus (P) fertilizer production from recycling of the ash. Manure fibre has a positive calorific value and may be used as a CO2-neutral fuel for combustion. The ashes from combustion are rich in P, an essential fertilizer compound. The study is based on samples of animal...

Single-particle characterization of ice-nucleating particles and ice particles residuals sampled by three different techniques

Science.gov (United States)

Kandler, Konrad; Worringen, Annette; Benker, Nathalie; Dirsch, Thomas; Mertes, Stephan; Schenk, Ludwig; Kästner, Udo; Frank, Fabian; Nillius, Björn; Bundke, Ulrich; Rose, Diana; Curtius, Joachim; Kupiszewski, Piotr; Weingartner, Ernest; Vochezer, Paul; Schneider, Johannes; Schmidt, Susan; Weinbruch, Stephan; Ebert, Martin

2015-04-01

During January/February 2013, at the High Alpine Research Station Jungfraujoch a measurement campaign was carried out, which was centered on atmospheric ice-nucleating particles (INP) and ice particle residuals (IPR). Three different techniques for separation of INP and IPR from the non-ice-active particles are compared. The Ice Selective Inlet (ISI) and the Ice Counterflow Virtual Impactor (Ice-CVI) sample ice particles from mixed phase clouds and allow for the analysis of the residuals. The combination of the Fast Ice Nucleus Chamber (FINCH) and the Ice Nuclei Pumped Counterflow Virtual Impactor (IN-PCVI) provides ice-activating conditions to aerosol particles and extracts the activated INP for analysis. Collected particles were analyzed by scanning electron microscopy and energy-dispersive X-ray microanalysis to determine size, chemical composition and mixing state. All INP/IPR-separating techniques had considerable abundances (median 20 - 70 %) of instrumental contamination artifacts (ISI: Si-O spheres, probably calibration aerosol; Ice-CVI: Al-O particles; FINCH+IN-PCVI: steel particles). Also, potential sampling artifacts (e.g., pure soluble material) occurred with a median abundance of separated by all three techniques. Soot was a minor contributor. Lead was detected in less than 10 % of the particles, of which the majority were internal mixtures with other particle types. Sea-salt and sulfates were identified by all three methods as INP/IPR. Most samples showed a maximum of the INP/IPR size distribution at 400 nm geometric diameter. In a few cases, a second super-micron maximum was identified. Soot/carbonaceous material and metal oxides were present mainly in the submicron range. ISI and FINCH yielded silicates and Ca-rich particles mainly with diameters above 1 µm, while the Ice-CVI also separated many submicron IPR. As strictly parallel sampling could not be performed, a part of the discrepancies between the different techniques may result from

IBA and synchrotron methods for sub-micron fine particle characterisation

International Nuclear Information System (INIS)

Cohen, D.D.; Siegele, R. Stampfl. A.; Cai, Z.; Ilinski, P.; Rodrigues, W.; Legnini, D.G.; Yun, W.; Lai, B.

1999-01-01

Fine air-borne particles, whose average diameters are 2.5 μm and less (PM2.5), are known to play significant roles in a number of human and environmental issues. They may penetrate deep into the human lung system and are believed, due to their small size or due to toxins adsorbed onto their surfaces, to be responsible for up to 60,000 and 10,000 deaths in the U.S. and U.K. respectively. Health studies within NSW, Australia carried out by the NSW EPA, have shown increased hospital admissions and excess deaths related to high fine particle pollution episodes. A number of environmental issues are affected by the amount and type of fine-particles in the air. The white and brown hazes that occur in populated cities causing poor visibility are due to light scattering from fine particles. These same particles are easily transported large distances in the lower atmosphere playing a key role in global pollution and climate forcing. Current knowledge of fine-particle concentrations and constituents is very limited. Sources of fine particles are both natural and man-made. Over the past few years considerable work on the characterisation of these particles has been going on at ANSTO using accelerator based ion beam analysis (IBA) methods. X-ray fluorescence using ion beams from accelerators and synchrotron fluorescence are complementary techniques. This is well demonstrated by the plot. PIXE has higher cross sections for low Z elements, but for high Z elements closer to the excitation energy (16keV) synchrotron radiation cross sections are larger. Both techniques are multi-elemental analysis techniques

Formation of fine particles in co-combustion of coal and solid recovered fuel in a pulverized coal-fired power station

DEFF Research Database (Denmark)

Wu, Hao; Pedersen, Anne Juul; Glarborg, Peter

2011-01-01

showed an ultrafine mode centered at approximately 0.1 μm. Compared with coal combustion, co-combustion of coal and SRF increased the formation of submicron particles, especially ultrafine particles below 0.2 μm. The morphology of the particles indicated that supermicron particles were primarily formed...... by the melting of minerals. The ultrafine particles were generated through nucleation and coagulation of vaporized inorganic species, while for the particles in between supermicron and ultrafine particles, condensation of vaporized species or aggregation of nucleates on the existing spherical submicron particles...... appear to be an important formation mechanism. The elemental composition of the particles from coal combustion showed that S and Ca were significantly enriched in ultrafine particles and P was also enriched considerably. However, compared with supermicron particles, the contents of Al, Si and K were...

Forced convection heat transfer with slurry of phase change material in circular ducts: A phenomenological approach

International Nuclear Information System (INIS)

Royon, Laurent; Guiffant, Gerard

2008-01-01

A model describing the thermal behaviour of a slurry of phase change material flow in a circular duct is presented. Reactors connected in series are considered for the representation of the circular duct with constant wall temperature. A phenomenological equation is formulated to take account of the heat generation due to phase change in the particles. Results of the simulation present a plateau of temperature along the longitudinal direction, characteristic of the phase change. The effect of different parameters such as the Reynolds number, the weight fraction and the temperature of the cold spring on the length of the plateau is analysed. A correlation resulting from numerical results is proposed for use in the determination of the characteristics of the exchanger for a phase change material slurry

Technical Report on NETL's Non Newtonian Multiphase Slurry Workshop: A path forward to understanding non-Newtonian multiphase slurry flows

Energy Technology Data Exchange (ETDEWEB)

Guenther, Chris [National Energy Technology Lab. (NETL), Morgantown, WV (United States); Garg, Rahul [National Energy Technology Lab. (NETL), Morgantown, WV (United States)

2013-08-19

The Department of Energy’s (DOE) National Energy Technology Laboratory (NETL) sponsored a workshop on non-Newtonian multiphase slurry at NETL’s Morgantown campus August 19 and 20, 2013. The objective of this special two-day meeting of 20-30 invited experts from industry, National Labs and academia was to identify and address technical issues associated with handling non-Newtonian multiphase slurries across various facilities managed by DOE. Particular emphasis during this workshop was placed on applications managed by the Office of Environmental Management (EM). The workshop was preceded by two webinars wherein personnel from ORP and NETL provided background information on the Hanford WTP project and discussed the critical design challenges facing this project. In non-Newtonian fluids, viscosity is not constant and exhibits a complex dependence on applied shear stress or deformation. Many applications under EM’s tank farm mission involve non-Newtonian slurries that are multiphase in nature; tank farm storage and handling, slurry transport, and mixing all involve multiphase flow dynamics, which require an improved understanding of the mechanisms responsible for rheological changes in non-Newtonian multiphase slurries (NNMS). To discuss the issues in predicting the behavior of NNMS, the workshop focused on two topic areas: (1) State-of-the-art in non-Newtonian Multiphase Slurry Flow, and (2) Scaling up with Confidence and Ensuring Safe and Reliable Long-Term Operation.

Prediction of changes in important physical parameters during composting of separated animal slurry solid fractions

DEFF Research Database (Denmark)

Chowdhury, Md Albarune; de Neergaard, Andreas; Jensen, Lars Stoumann

2014-01-01

Solid-liquid separation of animal slurry, with solid fractions used for composting, has gained interest recently. However, efficient composting of separated animal slurry solid fractions (SSFs) requires a better understanding of the process dynamics in terms of important physical parameters...... and their interacting physical relationships in the composting matrix. Here we monitored moisture content, bulk density, particle density and air-filled porosity (AFP) during composting of SSF collected from four commercially available solid-liquid separators. Composting was performed in laboratory-scale reactors...... for 30 days (d) under forced aeration and measurements were conducted on the solid samples at the beginning of composting and at 10-d intervals during composting. The results suggest that differences in initial physical properties of SSF influence the development of compost maximum temperatures (40...

Natural convection heat transfer from a heated horizontal cylinder with Microencapsulated Phase-Change-Material slurries

International Nuclear Information System (INIS)

Kubo, Shinji; Akino, Norio; Tanaka, Amane; Nagashima, Akira

1998-01-01

The present study investigates natural convection heat transfer from a heated cylinder cooled by a water slurry of Microencapsulated Phase Change Material (MCPCM). A normal paraffin hydrocarbon with carbon number of 18 and melting point of 27.9degC, is microencapsulated by Melamine resin into particles of which average diameter is 9.5 μm and specific weight is same as water. The slurry of the MCPCM and water is put into a rectangular enclosure with a heated horizontal cylinder. The heat transfer coefficients of the cylinder were evaluated. Changing the concentrations of PCM and temperature difference between cylinder surface and working fluid. Addition of MCPCM into water, the heat transfer is enhanced significantly comparison with pure water in cases with phase change and is reduced slightly in cases without phase change. (author)

NATO Advanced Study Institute on Physics of Submicron Semiconductor Devices

CERN Document Server

Ferry, David; Jacoboni, C

1988-01-01

The papers contained in the volume represent lectures delivered as a 1983 NATO ASI, held at Urbino, Italy. The lecture series was designed to identify the key submicron and ultrasubmicron device physics, transport, materials and contact issues. Nonequilibrium transport, quantum transport, interfacial and size constraints issues were also highlighted. The ASI was supported by NATO and the European Research Office. H. L. Grubin D. K. Ferry C. Jacoboni v CONTENTS MODELLING OF SUB-MICRON DEVICES.................. .......... 1 E. Constant BOLTZMANN TRANSPORT EQUATION... ... ...... .................... 33 K. Hess TRANSPORT AND MATERIAL CONSIDERATIONS FOR SUBMICRON DEVICES. . .. . . . . .. . . . .. . .. . .... ... .. . . . .. . . . .. . . . . . . . . . . 45 H. L. Grubin EPITAXIAL GROWTH FOR SUB MICRON STRUCTURES.................. 179 C. E. C. Wood INSULATOR/SEMICONDUCTOR INTERFACES.......................... 195 C. W. Wilms en THEORY OF THE ELECTRONIC STRUCTURE OF SEMICONDUCTOR SURFACES AND INTERFACES...................

Biovailability of copper and zinc in pig and cattle slurries

NARCIS (Netherlands)

Jakubus, M.; Dach, J.; Starmans, D.A.J.

2013-01-01

Slurry is an important source of macronutrients, micro-nutrients and organic matter. Despite the considerable fertilizer value of slurry, it may be abundant in amounts of copper and zinc originating from dietary. The study presents quantitative changes in copper and zinc in individual slurries (pig

Bloch-Wave Engineered Submicron Diameter Micropillars with Quality Factors Exceeding 10,000

DEFF Research Database (Denmark)

Hofling, S.; Lermer, M.; Gregersen, Niels

2011-01-01

Adiabatic design submicron diameter quantum-dot micropillars have been designed and implemented for cavity quantum electrodynamics experiments. Ultra-high experimental quality factors (>10,000) are obtained for submicron diameters and strong light-matter interaction is observed....

Ionic composition of submicron particles (PM1.0) during the long-lasting haze period in January 2013 in Wuhan, central China.

Science.gov (United States)

Cheng, Hairong; Gong, Wei; Wang, Zuwu; Zhang, Fan; Wang, Xinming; Lv, Xiaopu; Liu, Jia; Fu, Xiaoxin; Zhang, Gan

2014-04-01

In January 2013, a long-lasting severe haze episode occurred in Northern and Central China; at its maximum, it covered a land area of approximately 1.4 million km(2). In Wuhan, the largest city in Central China, this event was the most severe haze episode in the 21st century. Aerosol samples of submicron particles (PM1.0) were collected during the long-lasting haze episode at an urban site and a suburban site in Wuhan to investigate the ion characteristics of PM1.0 in this area. The mass concentrations of PM1.0 and its water-soluble inorganic ions (WSIIs) were almost at the same levels at two sites, which indicates that PM1.0 pollution occurs on a regional scale in Wuhan. WSIIs (Na(+), NH4(+), K(+), Mg(2+), Ca(2+), Cl(-), NO3(-) and SO4(2-)) were the dominant chemical species and constituted up to 48.4% and 47.4% of PM1.0 at WD and TH, respectively. The concentrations of PM1.0 and WSIIs on haze days were approximately two times higher than on normal days. The ion balance calculations indicate that the particles were more acidic on haze days than on normal days. The results of the back trajectory analysis imply that the high concentrations of PM1.0 and its water-soluble inorganic ions may be caused by stagnant weather conditions in Wuhan. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Vitrification of SRP waste by a slurry-fed ceramic melter

International Nuclear Information System (INIS)

Wicks, G.G.

1980-01-01

Savannah River Plant (SRP) high-level waste (HLW) can be vitrified by feeding a slurry, instead of a calcine, to a joule-heated ceramic melter. Potential advantages of slurry feeding include (1) use of simpler equipment, (2) elimination of handling easily dispersed radioactive powder, (3) simpler process control, (4) effective mixing, (5) reduced off-gas volume, and (6) cost savings. Assessment of advantages and disadvantages of slurry feeding along with experimental studies indicate that slurry feeding is a promising way of vitrifying waste

The attachment of radon daughters to submicron aerosol particles

International Nuclear Information System (INIS)

Grenier, M.G.; Bigu, J.

1984-04-01

A study of the effects of aerosol concentration, aerosol size distribution and relative humidity on the Working Level and the radon daughter concentration was conducted in a 3000 L radon environmental chamber. Typical values of the aerosol concentration varied in the 1 x 10 3 particles/cm 3 to 4.5 x 10 5 particles/cm 3 range. Various size distributions of aerosols that have mean diffusional aerodynamic diameters of .025 μm, .045 μm and .090 μm were tested. A good correlation was found between the Working Level and the aerosol concentration as well as the relative humidity. Most of the activity seems to be associated with particles of diameter between .05 μm and .2 μm. The results presented here are in agreement with work done by other investigators in the health physics field

Drag reduction of dense fine-grained slurries

Czech Academy of Sciences Publication Activity Database

Vlasák, Pavel; Chára, Zdeněk; Štern, Petr

2010-01-01

Roč. 58, č. 4 (2010), s. 261-270 ISSN 0042-790X R&D Projects: GA ČR(CZ) GAP105/10/1574 Institutional research plan: CEZ:AV0Z20600510 Keywords : kaolin slurry * drag reduction * experimental investigation * peptization * slurry rheology Subject RIV: BK - Fluid Dynamics Impact factor: 0.553, year: 2010

Anaerobic digestion as a slurry management strategy : a consequential life cycle assessment

Energy Technology Data Exchange (ETDEWEB)

Hamelin, L.; Wesnaes, M.; Wenzel, H.; Petersen, B.M. [Southern Denmark Univ. (Denmark). Inst. of Chemical Engineering, Biotechnology and Environmental Technology

2010-07-01

Anaerobic digestion of slurry represents an environmental opportunity for both slurry management and renewable energy production in countries with high animal density. This study evaluated the environmental impacts of 4 biogas production alternatives in which slurry was the only input in the process, without supplementary addition of easily degradable carbon. This was achieved by exposing the slurry to different separation technologies. The biomass mixture input for biogas production included solid fraction from slurry separation as well as raw slurry, proportioned in order to achieve economical methane yield. The separation processes considered in this study were mechanical separation; mechanical separation combined with the addition of flocculants; and mechanical separation combined with a thermal treatment. Four biogas alternatives were compared to a reference slurry management scenario, notably to use the slurry as a fertilizer without prior treatment. The modelling was based on Danish conditions and used the consequential life cycle assessment methodology. The produced biogas was used for production of heat and power and the degassed slurry was used as an organic fertilizer.

Semi-solid A356 alloy slurry for rheocasting prepared by a new process

Directory of Open Access Journals (Sweden)

Liu Zheng

2013-05-01

Full Text Available To obtain the semi-solid slurry with uniform and fine structure morphology that satisfies the requirement of rheocasting process, a new process for preparing semi-solid Al alloy slurry was developed, in which local chilling was combined with low superheat pouring and slight electromagnetic stirring (LSPSEMS. The morphology and the size of primary α-Al in the A356 alloy slurry prepared with the new process, i.e., LSPSEMS with local chilling, were investigated using MIAPS image analyzing software, and the grain refinement mechanism was discussed. The results indicate that the semi-solid primary phase consists of particle-like or globular-like α-Al, and the morphology and grain size of primary α-Al in the slurry can be markedly improved by the new process. The fine primary α-Al distributes uniformly in the slurry, which satisfies the requirement of rheocasting. Compared with the alloy prepared by LSPSEMS, the average equal-area-circle grain diameter of primary α-Al in semi-solid A356 alloy ingot prepared by the new process is decreased from 85.6 μm to 68.8 μm at the central area, 112.6 μm to 77.6 μm at the transition area and is 84.7 μm in the edge area, respectively. The corresponding shape factor of primary α-Al is increased from 0.78 to 0.83, 0.54 to 0.77 and 0.28 to 0.59, respectively. In addition, the pouring temperature could be suitably raised from 620-630 ℃ of the traditional process to 650 ℃ using this technique, which is convenient for practical operation. The mechanism of grain refinement, in the new process, is that the local chilling quickens up the temperature decrease in the center of the melt. The nuclei could not grow up in a short time so the finer grains are formed in the melt.

Parametric Study of Slurry-Erosion of Hydroturbine Steels with and without Detonation Gun Spray Coatings using Taguchi Technique

Science.gov (United States)

Grewal, Harpreet Singh; Bhandari, Sanjeev; Singh, Harpreet

2012-09-01

WC-Co-Cr coatings were deposited on some hydroturbine 13Cr4Ni and 16Cr5Ni steels by the detonation-gun spray process. An in-depth characterization of the as-sprayed coating was done using X-ray diffraction (XRD) and scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDS) techniques. Microhardness and porosity measurements were also made. The coating was found to have a typical splat-like morphology with some indications of unmelted carbide particles. The XRD results showed the presence of WC as the primary phase along with W2C and Co6W6C as secondary phases. Furthermore, the slurry erosion behavior of the coatings was investigated to ascertain the usefulness of the coatings to reduce the slurry erosion of the steels. The effect of four operating factors viz. the velocity, impact angle, concentration, and particle size on the slurry erosion of coated and bare steels has been studied using a high-speed jet-type test rig. The sand used as an erodent was collected from a power plant to replicate the actual turbine conditions. It has been observed that the given cermet coating can enhance the erosion resistance of the steel. Velocity was found to be the most significant factor affecting the erosion behavior of the coating, whereas it was the erodent particle size in the case of uncoated steel. As evidenced from the SEM images, the platelet mechanism of erosion seemed to be the prominent one, causing the removal of material from the surface of the steel, whereas for the coating, the formation and interlinking of cracks resulted in the removal of material.

Heavy cement slurries; Pastas pesadas de cimento

Energy Technology Data Exchange (ETDEWEB)

Silva, Francisco Avelar da; Conceicao, Antonio C. Farias [PETROBRAS, XX (Brazil). Distrito de Perfuracao do Nordeste. Div. de Tecnicas de Perfuracao; Marins, Carlos Cesar Silva [PETROBRAS, XX (Brazil). Dept. de Perfuracao. Div. de Revestimento e Cimentacao

1990-12-31

When going deeper in a high pressure well, the only way to successfully cement your casing or linear is through the use of heavy cement slurry. In 1987 PETROBRAS geologists presented to the Drilling Department a series of deep, hot and high pressure wells to be drilled. The Casing and Cement Division of this department then started a program to face this new challenge. This paper introduces the first part of this program and shows how PETROBRAS is dealing with heavy weight slurries. We present the slurry formulations tested in laboratory, the difficulties found in mixing them in the field, rheology measurements, API free water and API fluid loss from both laboratory and field samples. (author) 3 tabs.

Development of Pixel Front-End Electronics using Advanced Deep Submicron CMOS Technologies

CERN Document Server

Havránek, Miroslav; Dingfelder, Jochen

The content of this thesis is oriented on the R&D; of microelectronic integrated circuits for processing the signal from particle sensors and partially on the sensors themselves. This work is motivated by ongoing upgrades of the ATLAS Pixel Detector at CERN laboratory and by exploration of new technologies for the future experiments in particle physics. Evolution of technologies for the fabrication of microelectronic circuits follows Moore’s laws. Transistors become smaller and electronic chips reach higher complexity. Apart from this, silicon foundries become more open to smaller customers and often provide non-standard process options. Two new directions in pixel technologies are explored in this thesis: design of pixel electronics using ultra deep submicron (65 nm) CMOS technology and Depleted Monolithic Active Pixel Sensors (DMAPS). An independent project concerning the measurement of pixel capacitance with a dedicated measurement chip is a part of this thesis. Pixel capacitance is one of the key pa...

Simulation technique for slurries interacting with moving parts and deformable solids with applications

Science.gov (United States)

Mutabaruka, Patrick; Kamrin, Ken

2018-04-01

A numerical method for particle-laden fluids interacting with a deformable solid domain and mobile rigid parts is proposed and implemented in a full engineering system. The fluid domain is modeled with a lattice Boltzmann representation, the particles and rigid parts are modeled with a discrete element representation, and the deformable solid domain is modeled using a Lagrangian mesh. The main issue of this work, since separately each of these methods is a mature tool, is to develop coupling and model-reduction approaches in order to efficiently simulate coupled problems of this nature, as in various geological and engineering applications. The lattice Boltzmann method incorporates a large eddy simulation technique using the Smagorinsky turbulence model. The discrete element method incorporates spherical and polyhedral particles for stiff contact interactions. A neo-Hookean hyperelastic model is used for the deformable solid. We provide a detailed description of how to couple the three solvers within a unified algorithm. The technique we propose for rubber modeling/coupling exploits a simplification that prevents having to solve a finite-element problem at each time step. We also developed a technique to reduce the domain size of the full system by replacing certain zones with quasi-analytic solutions, which act as effective boundary conditions for the lattice Boltzmann method. The major ingredients of the routine are separately validated. To demonstrate the coupled method in full, we simulate slurry flows in two kinds of piston valve geometries. The dynamics of the valve and slurry are studied and reported over a large range of input parameters.

A simple biofilter for treatment of pig slurry in Malaysia.

Science.gov (United States)

Sommer, S G; Mathanpaal, G; Dass, G T

2005-03-01

On commercial pig production farms in South East (SE) Asia, the liquid effluent is often discharged into rivers. The discharge is a hazard to the environment and to the health of people using water from the river either for consumption or for irrigation. Therefore, a simple percolation biofilter for treatment of the liquid effluent was developed. Pig slurry was treated in test-biofilters packed with different biomass for the purpose of selecting the most efficient material, thereafter the efficiency of the biofilter was examined at farm scale with demo biofilters using the most efficient material. The effect of using "Effective Microorganisms" (EM) added to slurry that was treated with biofilter material mixed with Glenor KR+ was examined. Slurry treatment in the test-biofilters indicated that rice straw was better than coconut husks, wood shavings, rattan strips and oil palm fronds in reducing BOD. Addition of EM and Glenor KR+ to slurry and biofilter material, respectively, had no effect on the temperature of the biofilter material or on the concentrations of organic and inorganic components of the treated slurry. The BOD of slurry treated in test biofilters is reduced to between 80 and 637 mg O2 I(-1) and in the demo biofilter to between 3094 and 3376 mg O2 l(-1). The concentration of BOD in the effluent is related to the BOD in the slurry being treated and the BOD concentration in slurry treated in test biofilters was lower than BOD of slurry treated in demo biofilters. The demo biofilter can reduce BOD to between 52 an 56% of the original value, and TSS, COD (chemical oxygen demand) and ammonium (NH4+) to 41-55% of the original slurry. The treated effluent could not meet the standards for discharge to rivers. The composted biofilter material has a high content of nitrogen and phosphorus; consequently, the fertilizer value of the compost is high. The investments costs were 123 US dollar per SPP which has to be reduced if this method should be a treatment option

Effect of alkaline slurry on the electric character of the pattern Cu wafer

International Nuclear Information System (INIS)

Hu Yi; Liu Yuling; Liu Xiaoyan; He Yangang; Wang Liran; Zhang Baoguo

2011-01-01

For process integration considerations, we will investigate the impact of chemical mechanical polishing (CMP) on the electrical characteristics of the pattern Cu wafer. In this paper, we investigate the impacts of the CMP process with two kinds of slurry, one of which is acid slurry of SVTC and the other is FA/O alkaline slurry purchased from Tianjin Jingling Microelectronic Material Limited. Three aspects were investigated: resistance, capacitance and leakage current. The result shows that after polishing by the slurry of FA/O, the resistance is lower than the SVTC. After polishing by the acid slurry and FA/O alkaline slurry, the difference in capacitance is not very large. The values are 0.1 nF and 0.12 nF, respectively. The leakage current of the film polished by the slurry of FA/O is 0.01 nA, which is lower than the slurry of SVTC. The results show that the slurry of FA/O produced less dishing and oxide loss than the slurry of SVTC. (semiconductor technology)

Particle migration using local variation of the viscosity (LVOV) model in flow of a non-Newtonian fluid for ceramic tape casting

DEFF Research Database (Denmark)

Jabbaribehnam, Mirmasoud; Spangenberg, Jon; Hattel, Jesper Henri

2016-01-01

In this paper, the migration of secondary particles in a non-Newtonian ceramic slurry inthe tape casting process is investigated with the purpose of understanding the particle distribution patterns along the casting direction. The Ostwald-de Waele power law model for the non-Newtonian flow...... the substratevelocity (casting speed) leads to a more uniform distribution of the particles inside the ceramic slurry, in which case the shear induced particle migration is dominating over the gravity induced one....

Rheological properties of concentrated alumina slurries: influence of ph and dispersant agent

International Nuclear Information System (INIS)

Ewais, E.M.M.

2004-01-01

The relationship between the ph, the electrolyte concentrations and the rheological properties of high concentrated alumina slurries in aqueous medium is of great importance because it is considered to be the key to control the stability of the slurries from flocculation. Zeta potential of alumina slurries with and without Duramax C (dispersant agent) as a function of ph was studied. Two ph around the zero point of charge of alumina slurries were selected for the investigation of rheological properties. The rheological properties of aqueous alumina slurries with respect to different parameters, e.g.: viscosity, elastic modulus (storage modulus G) and viscous modulus (loss modulus G), were investigated. Viscosity measurements of the slurries as a function of Duramax C content at both ph 8.4 and 9.4) were used to determine the state of slurries. Three states of slurries, termed flocculated, partially de flocculated and fully de flocculated, were selected for further investigation. The viscosity of the three slurries at both ph as a function of shear rate was determined. Fully de flocculated slurry shows Newtonian behavior at all shear rates at both tested ph compared by the partial de flocculated and flocculated system. Results of investigation of G and G at ph of 9.4 as a function of applied stress explored the critical stress

An introduction to deep submicron CMOS for vertex applications

CERN Document Server

Campbell, M; Cantatore, E; Faccio, F; Heijne, Erik H M; Jarron, P; Santiard, Jean-Claude; Snoeys, W; Wyllie, K

2001-01-01

Microelectronics has become a key enabling technology in the development of tracking detectors for High Energy Physics. Deep submicron CMOS is likely to be extensively used in all future tracking systems. Radiation tolerance in the Mrad region has been achieved and complete readout chips comprising many millions of transistors now exist. The choice of technology is dictated by market forces but the adoption of deep submicron CMOS for tracking applications still poses some challenges. The techniques used are reviewed and some of the future challenges are discussed.

Synthesis and characterization of hollow {alpha}-Fe{sub 2}O{sub 3} sub-micron spheres prepared by sol-gel

Energy Technology Data Exchange (ETDEWEB)

Leon, Lizbet, E-mail: lizbetlf@gmail.com; Bustamante, Angel; Osorio, Ana; Olarte, G. S. [Universidad Nacional Mayor de San Marcos (Peru); Santos Valladares, Luis De Los, E-mail: ld301@cam.ac.uk; Barnes, Crispin H. W. [University of Cambridge, Cavendish Laboratory (United Kingdom); Majima, Yutaka [Tokyo Institute of Technology, Materials and Structures Laboratory (Japan)

2011-11-15

In this work we report the preparation of magnetic hematite hollow sub-micron spheres ({alpha}-Fe{sub 2}O{sub 3}) by colloidal suspensions of ferric nitrate nine-hydrate (Fe(NO{sub 3}){sub 3}{center_dot}9H{sub 2}O) particles in citric acid solution by following the sol-gel method. After the gel formation, the samples were annealed at different temperatures in an oxidizing atmosphere. Annealing at 180 Degree-Sign C resulted in an amorphous phase, without iron oxide formation. Annealing at 250 Degree-Sign C resulted in coexisting phases of hematite, maghemite and magnetite, whereas at 400 Degree-Sign C, only hematite and maghemite were found. Pure hematite hollow sub-micron spheres with porous shells were formed after annealing at 600 Degree-Sign C. The characterization was performed by X-ray diffraction (XRD), Moessbauer spectroscopy (MS) and scanning electron microscopy (SEM).

Cost-effectiveness of Low-dose Submicron Diclofenac Compared With Generic Diclofenac.

Science.gov (United States)

Mladsi, Deirdre; Ronquest, Naoko; Odom, Dawn; Miles, LaStella; Saag, Kenneth

2016-11-01

NSAIDs are commonly prescribed for the treatment of pain and inflammation. Despite the effectiveness of NSAIDs, concerns exist regarding their tolerability. Worldwide health authorities, including the European Medicines Agency, Health Canada, and the US Food and Drug Administration, have advised that NSAIDs be prescribed at the lowest effective dosage and for the shortest duration. Effective lowering of NSAID dosage without compromising pain relief has been demonstrated in randomized, controlled trials of the recently approved NSAID lower-dose submicron diclofenac. Building on previously published work from an independently published systematic review and meta-analysis, a linear dose-toxicity relationship between diclofenac dose and serious gastrointestinal (GI) events was recently demonstrated, indicating that reductions in adverse events (AEs) may be seen even with modest dose reductions in many patients. The objective of the present study was to estimate the potential reduction in risk for NSAID dose-related AEs, corresponding savings in health care costs, and the incremental cost-effectiveness of submicron diclofenac compared with generic diclofenac in the United States. Our decision-analytic cost-effectiveness model considered a subset of potential AEs that may be avoided by lowering NSAID dosage. To estimate the expected reductions in upper GI bleeding/perforation and major cardiovascular events with submicron diclofenac, our model used prediction equations estimated by meta-regressions using data from systematic literature reviews. Utilities, lifetime costs, and health outcomes associated with AEs were estimated using data from the literature. The face validity of the model structure and inputs was confirmed by clinical experts in the United States. Results were evaluated in 1-way and probabilistic sensitivity analyses. The model predicted that submicron diclofenac versus generic diclofenac could reduce the occurrence of modeled GI events (by 18

Recovering low-turbidity cutting liquid from silicon slurry waste.

Science.gov (United States)

Tsai, Tzu-Hsuan; Shih, Yu-Pei

2014-04-30

In order to recover a low-turbidity polyalkylene glycol (PAG) liquid from silicon slurry waste by sedimentation, temperatures were adjusted, and acetone, ethanol or water was used as a diluent. The experimental results show that the particles in the waste would aggregate and settle readily by using water as a diluent. This is because particle surfaces had lower surface potential value and weaker steric stabilization in PAG-water than in PAG-ethanol or PAG-acetone solutions. Therefore, water is the suggested diluent for recovering a low-turbidity PAG (sedimentation. After 50 wt.% water-assisted sedimentation for 21 days, the solid content of the upper liquid reduced to 0.122 g/L, and the turbidity decreased to 44 NTU. The obtained upper liquid was then vacuum-distillated to remove water. The final recovered PAG with 0.37 NTU had similar viscosity and density to the unused PAG and could be reused in the cutting process. Copyright © 2014 Elsevier B.V. All rights reserved.

Impact of Spherical Frit Beads on Simulated DWPF Slurries

International Nuclear Information System (INIS)

SMITH, MICHAEL

2005-01-01

It has been shown that the rheological properties of simulated Defense Waste Processing Facility (DWPF) melter feed with the glass former frit as mostly (90 weight percent) solid spherical particles (referred to as beads) were improved as the feed was less viscous as compared to DWPF melter feed that contained the normal irregular shaped frit particles. Because the physical design of the DWPF Slurry Mix Evaporator (SME), Melter Feed Tank (MFT), and melter feed loop are fixed, the impact of changing the rheology might be very beneficial. Most importantly, higher weight percent total solids feed might be processed by reducing the rheological properties (specifically yield stress) of the feed. Additionally, if there are processing problems, such as air entrainment or pumping, these problems might be alleviated by reducing the rheological properties, while maintaining targeted throughputs. Rheology modifiers are chemical, physical, or a combination of the two and can either thin or thicken the rheology of the targeted slurry. The beads are classified as a physical rheological modifier in this case. Even though the improved rheological properties of the feed in the above mentioned DWPF tanks could be quite beneficial, it is the possibility of increased melt rate that is the main driver for the use of beaded glass formers. By improving the rheological properties of the feed, the weight percent solids of the feed could be increased. This higher weight percent solids (less water) feed could be processed faster by the melter as less energy would be required to evaporate the water, and more would be available for the actual melting of the waste and the frit. In addition, the use of beads to thin the feed could possibly allow for the use of a lower targeted acid stoichiometry in the feed preparation process (if in fact acid stoichiometry is being driven by feed rheology as opposed to feed chemistry). Previous work by the Savannah River National Laboratory (SRNL) with the lab

Single stage high pressure centrifugal slurry pump

Science.gov (United States)

Meyer, John W.; Bonin, John H.; Daniel, Arnold D.

1984-03-27

Apparatus is shown for feeding a slurry to a pressurized housing. An impeller that includes radial passages is mounted in the loose fitting housing. The impeller hub is connected to a drive means and a slurry supply means which extends through the housing. Pressured gas is fed into the housing for substantially enveloping the impeller in a bubble of gas.

Use of radiation-induced polymers in cement slurries

International Nuclear Information System (INIS)

Knight, B.L.; Rhudy, J.S.; Gogarty, W.B.

1976-01-01

Water loss from cement slurries is reduced by incorporating within a cement slurry a polymer obtained as a product of radiation-induced polymerization of acrylamide and/or methacrylamide and acrylic acid, methacrylic acid, and/or alkali metal salts thereof. The polymerization is preferably carried out in 10-60 percent aqueous monomer solution with gamma radiation. The aqueous monomer solution preferably contains 25-99 percent acrylamide and 75-1 percent sodium acrylate. The polymer can be present in concentration of about 0.001 to about 3.0 weight percent, based on the aqueous phase of the slurry

Scanning SQUID susceptometers with sub-micron spatial resolution

Energy Technology Data Exchange (ETDEWEB)

Kirtley, John R., E-mail: jkirtley@stanford.edu; Rosenberg, Aaron J.; Palmstrom, Johanna C.; Holland, Connor M.; Moler, Kathryn A. [Department of Applied Physics, Stanford University, Stanford, California 94305-4045 (United States); Paulius, Lisa [Department of Physics, Western Michigan University, Kalamazoo, Michigan 49008-5252 (United States); Spanton, Eric M. [Department of Physics, Stanford University, Stanford, California 94305-4045 (United States); Schiessl, Daniel [Attocube Systems AG, Königinstraße 11A, 80539 Munich (Germany); Jermain, Colin L.; Gibbons, Jonathan [Department of Physics, Cornell University, Cornell, Ithaca, New York 14853 (United States); Fung, Y.-K.K.; Gibson, Gerald W. [IBM Research Division, T. J. Watson Research Center, Yorktown Heights, New York 10598 (United States); Huber, Martin E. [Department of Physics, University of Colorado Denver, Denver, Colorado 80217-3364 (United States); Ralph, Daniel C. [Department of Physics, Cornell University, Cornell, Ithaca, New York 14853 (United States); Kavli Institute at Cornell, Ithaca, New York 14853 (United States); Ketchen, Mark B. [OcteVue, Hadley, Massachusetts 01035 (United States)

2016-09-15

Superconducting QUantum Interference Device (SQUID) microscopy has excellent magnetic field sensitivity, but suffers from modest spatial resolution when compared with other scanning probes. This spatial resolution is determined by both the size of the field sensitive area and the spacing between this area and the sample surface. In this paper we describe scanning SQUID susceptometers that achieve sub-micron spatial resolution while retaining a white noise floor flux sensitivity of ≈2μΦ{sub 0}/Hz{sup 1/2}. This high spatial resolution is accomplished by deep sub-micron feature sizes, well shielded pickup loops fabricated using a planarized process, and a deep etch step that minimizes the spacing between the sample surface and the SQUID pickup loop. We describe the design, modeling, fabrication, and testing of these sensors. Although sub-micron spatial resolution has been achieved previously in scanning SQUID sensors, our sensors not only achieve high spatial resolution but also have integrated modulation coils for flux feedback, integrated field coils for susceptibility measurements, and batch processing. They are therefore a generally applicable tool for imaging sample magnetization, currents, and susceptibilities with higher spatial resolution than previous susceptometers.

Scanning SQUID susceptometers with sub-micron spatial resolution

International Nuclear Information System (INIS)

Kirtley, John R.; Rosenberg, Aaron J.; Palmstrom, Johanna C.; Holland, Connor M.; Moler, Kathryn A.; Paulius, Lisa; Spanton, Eric M.; Schiessl, Daniel; Jermain, Colin L.; Gibbons, Jonathan; Fung, Y.-K.K.; Gibson, Gerald W.; Huber, Martin E.; Ralph, Daniel C.; Ketchen, Mark B.

2016-01-01

Superconducting QUantum Interference Device (SQUID) microscopy has excellent magnetic field sensitivity, but suffers from modest spatial resolution when compared with other scanning probes. This spatial resolution is determined by both the size of the field sensitive area and the spacing between this area and the sample surface. In this paper we describe scanning SQUID susceptometers that achieve sub-micron spatial resolution while retaining a white noise floor flux sensitivity of ≈2μΦ_0/Hz"1"/"2. This high spatial resolution is accomplished by deep sub-micron feature sizes, well shielded pickup loops fabricated using a planarized process, and a deep etch step that minimizes the spacing between the sample surface and the SQUID pickup loop. We describe the design, modeling, fabrication, and testing of these sensors. Although sub-micron spatial resolution has been achieved previously in scanning SQUID sensors, our sensors not only achieve high spatial resolution but also have integrated modulation coils for flux feedback, integrated field coils for susceptibility measurements, and batch processing. They are therefore a generally applicable tool for imaging sample magnetization, currents, and susceptibilities with higher spatial resolution than previous susceptometers.

Methane Fermentation of Slurry with Chemical and Biological Additive

Directory of Open Access Journals (Sweden)

Anna Smurzyńska

2017-12-01

Full Text Available The problem of proper slurry management is primarily present in intensive livestock production. Industrialized livestock farms generate enormous quantities of manure droppings in a livestock-litter-free system. The traditional management of slurry is made by using it as a fertilizer. Alternative techniques used for neutralizing the detrimental effect of slurry are based on the use of chemical and biological additives, as well as by introducing aerobic environment through aerobic or anaerobic digestion, leading to methane fermentation. In the experiment, cattle manure was used, which came from the Przybroda farm belonging to the University of Life Sciences in Poznan. The aim of the study was to determine the biogas yield of slurry using the chemical and biological additive available on the Polish market. Mesophilic and thermophilic fermentation was used for the indication of the effectiveness of the employed fermentation process. The slurry was supplemented by a biological and chemical additive, i.e. effective microorganisms and – PRP, respectively. The experiment allowed to achieve a higher biogas yield during the use of effective microorganisms.

Bio-synthesis and antimicrobial activity of silver nanoparticles using anaerobically digested parthenium slurry.

Science.gov (United States)

Adur, Alaknanda J; Nandini, N; Shilpashree Mayachar, K; Ramya, R; Srinatha, N

2018-06-01

Silver nanoparticles were prepared through eco-friendly, cost effective, bio-mediated technique using anaerobically digested Parthenium hysterophorous digested slurry (PDS) for the first time. The synthesized nanoparticles were characterized through different techniques such as UV-Vis spectrophotometer for optical properties; X-ray diffractometer (XRD), high resolution transmission electron spectroscopy (HR-TEM) and Fourier Transform Infra Red (FTIR) Spectroscopy for structural property investigations. It was observed that the prepared silver nanoparticles were crystallized in face centered cubic crystal structure with an average particle size of 19 nm as confirmed from XRD. Also HR-TEM studies reveal the formation of nano-sized silver particles with face centered cubic nano structure. In addition, absorption spectra exhibit Surface Plasmon Resonance (SPR) which suggests the formation of silver nanoparticles. FTIR results show the presence of different characteristic functional groups and their stretching / bending vibrations in turn responsible for the bioreduction of silver ions in Parthenium digested slurry. Further investigations on antimicrobial activity were done by subjecting the synthesized silver nanoparticles on E-coli and Pseudomonas as marker organisms for the group of gram negative bacteria by well plate method on enrichment media. The result obtained shows a clear zone of inhibition confirming the antibacterial activity. Overall, the investigated results confirm the biosynthesized silver nanoparticles are potential candidates for antimicrobial activity applications. Copyright © 2018 Elsevier B.V. All rights reserved.

Toxicity Evaluation of Pig Slurry Using Luminescent Bacteria and Zebrafish

Directory of Open Access Journals (Sweden)

Wenyan Chen

2014-07-01

Full Text Available Biogas slurry has become a serious pollution problem and anaerobic digestion is widely applied to pig manure treatment for environmental protection and energy recovery. To evaluate environmental risk of the emission of biogas slurry, luminescent bacteria (Vibrio fischeri, larvae and embryos of zebrafish (Danio rerio were used to detect the acute and development toxicity of digested and post-treated slurry. Then the ability of treatment process was evaluated. The results showed that digested slurry displayed strong toxicity to both zebrafish and luminescent bacteria, while the EC50 for luminescent bacteria and the LC50 for larvae were only 6.81% (v/v and 1.95% (v/v respectively, and embryonic development was inhibited at just 1% (v/v. Slurry still maintained a high level of toxicity although it had been treated by membrane bioreactor (MBR, while the LC50 of larvae was 75.23% (v/v and there was a little effect on the development of embryos and V. fischeri; the results also revealed that the zebrafish larvae are more sensitive than embryos and luminescent bacteria to pig slurry. Finally, we also found the toxicity removal rate was higher than 90% after the treatment of MBR according to toxicity tests. In conclusion, further treatment should be used in pig slurry disposal or reused of final effluent.

Particle Emissions from Domestic Gas Cookers

DEFF Research Database (Denmark)

Glarborg, Peter; Livbjerg, Hans; Wagner, Ayten Yilmaz

2010-01-01

The authors experimentally studied the formation of submicron particles from a domestic gas cooker in a compartment free from external particle sources. The effects of fuel (methane, natural gas, odorant-free natural gas), primary aeration, flow rate, and fuel sulphur content on particle emissions...... of the emitted particles were found to have a mean value of about 7 nm for partially premixed flames, increasing to ∼10 nm for nonpremixed flames. The quantity of primary air had a strong impact on the particle emissions, showing a minimum at a primary aeration level of 60-65%. Presence of sulphur in small...... quantities may enhance particle formation under some conditions, but results were not conclusive....

Submicron Resolution Spectral-Domain Optical Coherence Tomography

KAUST Repository

Alarousu, Erkki; Jabbour, Ghassan

2013-01-01

Apparatuses and systems for submicron resolution spectral-domain optical coherence tomography (OCT) are disclosed. The system may use white light sources having wavelengths within 400-1000 nanometers, and achieve resolution below 1 .mu

The deposition of magnetite particles from high velocity water onto isothermal tubes

International Nuclear Information System (INIS)

Burrill, K.A.

1977-02-01

The deposition rate of magnetite particles from a high velocity water slurry onto isothermal metal tubes was measured. The effects of velocity (5 to 100 m/s), slurry concentration (200 to 1000 mg Fe/kg H 2 O), temperature (25 to 90 deg C), pH (4 to 10 at 25 deg C), and tube material (nickel, Zircaloy-4) on deposition rate were studied. The data are interpreteω in terms of two steps in series for deposition: a mass transfer step followed by a deposition or ''inertial coasting'' step. Mass transfer of particles through the bulk water phase apparently limits the deposition of particles at high Reynolds number (10 5 ). (author)

Upland and wetland vegetation establishment on coal slurry in northern Missouri

International Nuclear Information System (INIS)

Skeel, V.A.; Nawrot, J.R.

1998-01-01

Since the Cooperative Wildlife Research Laboratory's (CWRL) Mined Land Reclamation Program's first establishment of a wetland on slurry in 1976, industry, state, and federal agency interest in reclamation alternatives for inactive slurry has increased. CWRL has been involved in pre-reclamation site characterization and monitoring for inactive slurry impoundments throughout Illinois, Indiana, Kansas, Kentucky, Missouri, and Washington. Geochemical site characterization of three slurry impoundments at the AECI Bee Veer Mine located near Macon, Missouri began in April 1990. A substrate sampling grid was established for all slurry impoundments with a centerline orientated parallel to the discharge to decant flow pattern. Surface (0--6 in.) and subsurface (30--36 in.) slurry samples were collected annually and analyzed for acid-base balance, immediate acidity macro- and micro-nutrients, potential phytotoxic metallic ions and salts, and texture. Water table elevations and water quality were monitored quarterly from shallow (≤12 ft.) piezometers. General reclamation plans included annual (3 years) incremental limestone amendments (35--50 tons/acre) and direct vegetation establishment. Cool and warm season grasses dominate vegetation cover in upland habitats (slurry cell RDA1) while wetland habitats (palustrine emergent seasonally-permanently inundated) have been established in slurry cells (RDA2 and RDA3). Isolated hot spots continue to be amended with limestone and supplemental vegetation establishment is scheduled

Environmental consequences of future biogas technologies based on separated slurry.

Science.gov (United States)

Hamelin, Lorie; Wesnæs, Marianne; Wenzel, Henrik; Petersen, Bjørn M

2011-07-01

This consequential life cycle assessment study highlights the key environmental aspects of producing biogas from separated pig and cow slurry, a relatively new but probable scenario for future biogas production, as it avoids the reliance on constrained carbon cosubstrates. Three scenarios involving different slurry separation technologies have been assessed and compared to a business-as-usual reference slurry management scenario. The results show that the environmental benefits of such biogas production are highly dependent upon the efficiency of the separation technology used to concentrate the volatile solids in the solid fraction. The biogas scenario involving the most efficient separation technology resulted in a dry matter separation efficiency of 87% and allowed a net reduction of the global warming potential of 40%, compared to the reference slurry management. This figure comprises the whole slurry life cycle, including the flows bypassing the biogas plant. This study includes soil carbon balances and a method for quantifying the changes in yield resulting from increased nitrogen availability as well as for quantifying mineral fertilizers displacement. Soil carbon balances showed that between 13 and 50% less carbon ends up in the soil pool with the different biogas alternatives, as opposed to the reference slurry management.

Effect of lapping slurry on critical cutting depth of spinel

International Nuclear Information System (INIS)

Wang, Zhan-kui; Wang, Zhuan-kui; Zhu, Yong-wei; Su, Jian-xiu

2015-01-01

Highlights: • Measured spinel wafers’ hardness and crack length in different slurries. • Evaluated the softened layer thickness in different slurries. • Discussed the effect of slurries on critical cutting depth of spinel. - Abstract: The critical cutting depth for lapping process is very important because it influences the mode of material removal. In this paper, a serial of microscopic indentation experiments were carried out for measuring spinel wafers’ hardness and crack length in different lapping slurries. Their critical cutting depth and fracture toughness were calculated. X-ray photoelectron spectroscopy (XPS) was also employed to study the surface chemical composition and softened layer thickness of wafers in different slurries. Experimental results indicate that the softened layers of spinel wafers are formed due to the corrosion of lapping slurries, which leads to a lower hardness and a larger fracture toughness of samples, and increases the critical cutting depth. Among them, the critical cutting depth in ethylene glycol solution is the largest and up to 21.8 nm. The increase of critical cutting depth is helpful to modify the surface quality of the work-piece being lapped via ductile removal mode instead of brittle fracture mode

Method and apparatus for in-situ drying investigation and optimization of slurry drying methodology

Science.gov (United States)

Armstrong, Beth L.; Daniel, Claus; Howe, Jane Y.; Kiggans, Jr, James O.; Sabau, Adrian S.; Wood, III, David L.; Kalnaus, Sergiy

2016-05-10

A method of drying casted slurries that includes calculating drying conditions from an experimental model for a cast slurry and forming a cast film. An infrared heating probe is positioned on one side of the casted slurry and a thermal probe is positioned on an opposing side of the casted slurry. The infrared heating probe may control the temperature of the casted slurry during drying. The casted slurry may be observed with an optical microscope, while applying the drying conditions from the experimental model. Observing the casted slurry includes detecting the incidence of micro-structural changes in the casted slurry during drying to determine if the drying conditions from the experimental model are optimal.

Effect of flotation on preparation of coal-water slurries

Energy Technology Data Exchange (ETDEWEB)

Ding, K.; Laskowski, J.S. [University of British Columbia, Vancouver, BC (Canada)

2009-07-01

In order to study the effect of flotation reagents on the properties of coal-water slurry, a sub-bituminous coal was cleaned via either forward flotation or reverse flotation. The froth product from the forward flotation, obtained with the use of diesel oil and MIBC, and the tailings of the reverse flotation, carried out with dextrin-tannic acid depressants and dodecyltrimethylammonium chloride collector, were used in the preparation of coal-water slurries. It was shown that while it was possible to obtain the coal-water slurry with a high-solids content from the coal rendered hydrophilic (tailings from the coal reverse flotation), in the case of the hydrophobic product (froth product from the forward flotation) a dispersing agent was required to obtain the coal-water slurry of the same high-solids content.

An Enhanced Factor Analysis of Performance Degradation Assessment on Slurry Pump Impellers

Directory of Open Access Journals (Sweden)

Shilong Sun

2017-01-01

Full Text Available Slurry pumps, such as oil sand pumps, are widely used in industry to convert electrical energy to slurry potential and kinetic energy. Because of adverse working conditions, slurry pump impellers are prone to suffer wear, which may result in slurry pump breakdowns. To prevent any unexpected breakdowns, slurry pump impeller performance degradation assessment should be immediately conducted to monitor the current health condition and to ensure the safety and reliability of slurry pumps. In this paper, to provide an alternative to the impeller health indicator, an enhanced factor analysis based impeller indicator (EFABII is proposed. Firstly, a low-pass filter is employed to improve the signal to noise ratios of slurry pump vibration signals. Secondly, redundant statistical features are extracted from the filtered vibration signals. To reduce the redundancy of the statistic features, the enhanced factor analysis is performed to generate new statistical features. Moreover, the statistic features can be automatically grouped and developed a new indicator called EFABII. Data collected from industrial oil sand pumps are used to validate the effectiveness of the proposed method. The results show that the proposed method is able to track the current health condition of slurry pump impellers.

Development of Syringe/Bottle Hybrids for Sampling Slurries

International Nuclear Information System (INIS)

Coleman, C.J.

1998-01-01

A convenient and effective sample bottle system based on simple modifications of disposable plastic syringes and bottles has been devised and tested for slurry samples. Syringe/ bottle hybrids (hereafter referred to as syringe bottles) have the convenience of regular flat-bottom bottles with screw cap closures. In addition, the syringe imparts a sliding and adjustable bottom to the bottle that forces the entire contents from the bottle. The system was designed especially to collect samples for high temperature work-ups of DWPF slurry samples. The syringe bottles together with fixed-bottom sample vial inserts would provide the DWPF with convenient and reliable methods for dealing with slurry samples

Use of metallic glasses for fabrication of structures with submicron dimensions

Science.gov (United States)

Wiley, John D.; Perepezko, John H.

1986-01-01

Patterned structures of submicron dimension formed of supported or unsupported amorphous metals having submicron feature sizes characterized by etching behavior sufficient to allow delineation of sharp edges and smooth flat flanks, resistance to time-dependent dimensional changes caused by creep, flow, in-diffusion of unwanted impurities, out-diffusion of constituent atoms, void formation, grain growth or phase separation and resistance to phase transformations or compound formation.

Simulation of dynamic magnetic particle capture and accumulation around a ferromagnetic wire

Energy Technology Data Exchange (ETDEWEB)

Choomphon-anomakhun, Natthaphon [Department of Physics, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330 (Thailand); Ebner, Armin D. [Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208 (United States); Natenapit, Mayuree [Department of Physics, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok 10330 (Thailand); Ritter, James A. [Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208 (United States)

2017-04-15

A new approach for modeling high gradient magnetic separation (HGMS)-type systems during the time-dependent capture and accumulation of magnetic particles by a ferromagnetic wire was developed. This new approach assumes the fluid (slurry) viscosity, comprised of water and magnetic particles, is a function of the magnetic particle concentration in the fluid, with imposed maxima on both the particle concentration and fluid viscosity to avoid unrealistic limits. In 2-D, the unsteady-state Navier-Stokes equations for compressible fluid flow and the unsteady-state continuity equations applied separately to the water and magnetic particle phases in the slurry were solved simultaneously, along with the Laplace equations for the magnetic potential applied separately to the slurry and wire, to evaluate the velocities and concentrations around the wire in a narrow channel using COMSOL Multiphysics. The results from this model revealed very realistic magnetically attractive and repulsive zones forming in time around the wire. These collection zones formed their own impermeable viscous phase during accumulation that was also magnetic with its area and magnetism impacting locally both the fluid flow and magnetic fields around the wire. These collection zones increased with an increase in the applied magnetic field. For a given set of conditions, the capture ability peaked and then decreased to zero at infinite time during magnetic particle accumulation in the collection zones. Predictions of the collection efficiency from a steady-state, clean collector, trajectory model could not show this behavior; it also agreed only qualitatively with the dynamic model and then only at the early stages of collection and more so at a higher applied magnetic field. Also, the collection zones decreased in size when the accumulation regions included magnetic particle magnetization (realistic) compared to when they excluded it (unrealistic). Overall, this might be the first time a mathematical

Enhanced treatment of refinery soils with open-system slurry reactors

International Nuclear Information System (INIS)

Blackburn, J.W.; Lee, M.K.; Horn, W.C.

1995-01-01

Refinery site cleanups of residual hydrocarbons arising from long-term operations have become a concern. Because contaminated soil has been generated over many years from spills of many types of materials, it is often difficult to identify the actual spilled material. Because many of these materials are weathered, the less degradable fractions can predominate, creating a challenge for bioremedial process solutions. Open-system slurry reactors were run with an aged refinery soil after a 6-month period of field bioremediation in which 23% TPH removal resulted. The open system (a system where the liquid medium was replaced daily and the solids were retained in the reactor for 2 weeks) achieved 60 to 80% total petroleum hydrocarbon (TPH) removal based on the initial, prefield bioremediation soil concentration. A process concept twice as effective as other bioremediation schemes has been devised that takes advantage of the formation and removal of small black particulate solids in an open or continuous slurry reactor configuration. These small black particles are chemically or biologically produced in the open system and with their small size and low density are easily elutriated from the bioreactor as the liquid medium is changed. A statistically designed experiment has determined optimal values of nutrients, temperature, and mixing

Pressurized Vessel Slurry Pumping

International Nuclear Information System (INIS)

Pound, C.R.

2001-01-01

This report summarizes testing of an alternate ''pressurized vessel slurry pumping'' apparatus. The principle is similar to rural domestic water systems and ''acid eggs'' used in chemical laboratories in that material is extruded by displacement with compressed air

Design and characterization of radiation resistant integrated circuits for the LHC particle detectors using deep sub-micron CMOS technologies

International Nuclear Information System (INIS)

Anelli, Giovanni Maria

2000-01-01

The electronic circuits associated with the particle detectors of the CERN Large Hadron Collider (LHC) have to work in a highly radioactive environment. This work proposes a methodology allowing the design of radiation resistant integrated circuits using the commercial sub-micron CMOS technology. This method uses the intrinsic radiation resistance of ultra-thin grid oxides, the technology of enclosed layout transistors (ELT), and the protection rings to avoid the radio-induced creation of leakage currents. In order to check the radiation tolerance level, several test structures have been designed and tested with different radiation sources. These tests have permitted to study the physical phenomena responsible for the damages induced by the radiations and the possible remedies. Then, the particular characteristics of ELT transistors and their influence on the design of complex integrated circuits has been explored. The modeling of the W/L ratio, the asymmetries (for instance in the output conductance) and the performance of ELT couplings have never been studied yet. The noise performance of the 0.25 μ CMOS technology, used in the design of several integrated circuits of the LHC detectors, has been characterized before and after irradiation. Finally, two integrated circuits designed using the proposed method are presented. The first one is an analogic memory and the other is a circuit used for the reading of the signals of one of the LHC detectors. Both circuits were irradiated and have endured very high doses practically without any sign of performance degradation. (J.S.)

Fischer-Tropsch Slurry Reactor modeling

Energy Technology Data Exchange (ETDEWEB)

Soong, Y.; Gamwo, I.K.; Harke, F.W. [Pittsburgh Energy Technology Center, PA (United States)] [and others

1995-12-31

This paper reports experimental and theoretical results on hydrodynamic studies. The experiments were conducted in a hot-pressurized Slurry-Bubble Column Reactor (SBCR). It includes experimental results of Drakeol-10 oil/nitrogen/glass beads hydrodynamic study and the development of an ultrasonic technique for measuring solids concentration. A model to describe the flow behavior in reactors was developed. The hydrodynamic properties in a 10.16 cm diameter bubble column with a perforated-plate gas distributor were studied at pressures ranging from 0.1 to 1.36 MPa, and at temperatures from 20 to 200{degrees}C, using a dual hot-wire probe with nitrogen, glass beads, and Drakeol-10 oil as the gas, solid, and liquid phase, respectively. It was found that the addition of 20 oil wt% glass beads in the system has a slight effect on the average gas holdup and bubble size. A well-posed three-dimensional model for bed dynamics was developed from an ill-posed model. The new model has computed solid holdup distributions consistent with experimental observations with no artificial {open_quotes}fountain{close_quotes} as predicted by the earlier model. The model can be applied to a variety of multiphase flows of practical interest. An ultrasonic technique is being developed to measure solids concentration in a three-phase slurry reactor. Preliminary measurements have been made on slurries consisting of molten paraffin wax, glass beads, and nitrogen bubbles at 180 {degrees}C and 0.1 MPa. The data show that both the sound speed and attenuation are well-defined functions of both the solid and gas concentrations in the slurries. The results suggest possibilities to directly measure solids concentration during the operation of an autoclave reactor containing molten wax.

Evaluation of plant available nitrogen in concentrated pig slurry

International Nuclear Information System (INIS)

Ramirez, M.; Comas, J.; Pujola, M.

2009-01-01

In Northeast Spin the expansion of the pig industry has brought as a result the production of vast amounts of pig slurry that exceeds field crops fertilization needs and consequently has contributed to the environmental deterioration of the region particularly ground water with NO 3 pollution. Under such circumstances, it is needed to treat and/or export pig slurry. During the last year the implantation of cogeneration plants that take advantage of the surplus of energy to produce concentrate pig slurry by water evaporation that could easily transported. (Author)

The Settling and Compaction of Nuclear Waste Slurries

International Nuclear Information System (INIS)

MACLEAN, G.T.

1999-01-01

The settling and compaction of simulated and real nuclear waste slurries were extensively studied. Experiments were carried out with simulated wastes at laboratory and large-scale sizes, and the results compared. A model of settling was derived and a method developed to correlate and scale-up settling data for different slurries and vessel sizes

Agronomic valuing of slurry for management in common

International Nuclear Information System (INIS)

Gomez, M.; Estevez, M. D.; Faz, A.; Olivares, A. B.; Climent, V.

2009-01-01

Due to the intensification of livestock production and the concentration of holdings in specific areas, has disrupted the balance between production and utilization of swine waste in agriculture. given the volume of slurry generated in Murcia, and the total cultivable area and considering the legislation, RD 261/1996, which allows a maximum application of 170 kg N/ha year in areas designated as vulnerable, it is estimated that to implement the slurry generated in the region in a year, would require only half the arable land devoted to irrigation. In this way, this study has included detailed monitoring of the effect of the application of ping slurry at a concentration recommended on the properties and chemical, physical and biological properties of soil, water and plant to determine the influence of slurry on the reserve of organic matter in each of these crops, as well as contaminated soils, through the creation of a pilot system for managing livestock waste in accordance with preventive measures that allow for their optimal use, without risk of contamination for the system water-soil-plant. (Author 6 refs.

Coal waste slurries as a fuel for integrated gasification combined cycle plants

Directory of Open Access Journals (Sweden)

Lutynski Marcin A.

2016-01-01

Full Text Available The article summarizes recent development in integrated gasification combined cycle technology and lists existing and planned IGCC plants. A brief outlook on the IGCC gasification technology is given with focus on entrained-flow gasifiers where the low-quality coal waste slurry fuel can be used. Desired properties of coal and ash for entrained-flow gasifiers are listed. The coal waste slurries, which were deposited at impoundments in Upper Silesian Coal Basin, were considered as a direct feed for such gasifiers. The average ash content, moisture content and lower heating value were analysed and presented as an average values. Entrained-flow commercial gasifiers can be considered as suitable for the coal slurry feed, however the ash content of coal slurries deposited in impoundments is too high for the direct use as the feed for the gasifiers. The moisture content of slurries calculated on as received basis meets the requirements of entrained-flow slurry feed gasifiers. The content of fines is relatively high which allow to use the slurries in entrained-flow gasifiers.

Deformation Behavior of Sub-micron and Micron Sized Alumina Particles in Compression.

Energy Technology Data Exchange (ETDEWEB)

Sarobol, Pylin; Chandross, Michael E.; Carroll, Jay; Mook, William; Boyce, Brad; Kotula, Paul Gabriel; McKenzie, Bonnie Beth; Bufford, Daniel Charles; Hall, Aaron Christopher.

2014-09-01

The ability to integrate ceramics with other materials has been limited due to high temperature (>800degC) ceramic processing. Recently, researchers demonstrated a novel process , aerosol deposition (AD), to fabricate ceramic films at room temperature (RT). In this process, sub - micro n sized ceramic particles are accelerated by pressurized gas, impacted on the substrate, plastically deformed, and form a dense film under vacuum. This AD process eliminates high temperature processing thereby enabling new coatings and device integration, in which ceramics can be deposited on metals, plastics, and glass. However, k nowledge in fundamental mechanisms for ceramic particle s to deform and form a dense ceramic film is still needed and is essential in advancing this novel RT technology. In this wo rk, a combination of experimentation and atomistic simulation was used to determine the deformation behavior of sub - micron sized ceramic particle s ; this is the first fundamental step needed to explain coating formation in the AD process . High purity, singl e crystal, alpha alumina particles with nominal size s of 0.3 um and 3.0 um were examined. Particle characterization, using transmission electron microscopy (TEM ), showed that the 0.3 u m particles were relatively defect - free single crystals whereas 3.0 u m p articles were highly defective single crystals or particles contained low angle grain boundaries. Sub - micron sized Al 2 O 3 particles exhibited ductile failure in compression. In situ compression experiments showed 0.3um particles deformed plastically, fractured, and became polycrystalline. Moreover, dislocation activit y was observed within the se particles during compression . These sub - micron sized Al 2 O 3 particles exhibited large accum ulated strain (2 - 3 times those of micron - sized particles) before first fracture. I n agreement with the findings from experimentation , a tomistic simulation s of nano - Al 2 O 3 particles showed dislocation slip and

Corrosion behavior of austempered ductile iron (ADI) in iron ore slurry

African Journals Online (AJOL)

Corrosion behavior of austempered ductile iron (ADI) in iron ore slurry was studied as a function of the microstructure developed by austempering at 380 and 300°C for different exposure time in the slurry. The corrosion rates of the ADI balls immersed in the iron ore slurry was determined using weight loss method.

Fabrication, microstructure, and mechanical properties of high strength cobalt sub-micron structures

International Nuclear Information System (INIS)

Jin Sumin; Burek, Michael J.; Evans, Robert D.; Jahed, Zeinab; Leung, Michael C.; Evans, Neal D.; Tsui, Ting Y.

2012-01-01

The mechanical properties exhibited by sub-micron scale columnar structures of cobalt, fabricated by electron beam lithography and electroplating techniques, were investigated through uniaxial compression. Transmission electron microscopy analyses show these specimens possess a microstructure with sub-micron grains which are elongated and aligned near to the pillar loading axis. In addition, small nanocrystalline cobalt crystals are also present within the columnar structure. These specimens display exceptional mechanical strength comparable with both bulk polycrystalline and nanocrystalline cobalt deposited by electroplating. Size-dependent softening with shrinking sample dimensions is also observed in this work. Additionally, the strength of these sub-micron structures appears to be strain rate sensitive and comparable with bulk nanocrystalline cobalt specimens.

Adhesion of solid particles to gas bubbles. Part 2: Experimental

NARCIS (Netherlands)

Omota, Florin; Dimian, Alexandre C.; Bliek, A.

2006-01-01

In slurry bubble columns, the adhesion of solid catalyst particles to bubbles may significantly affect the G–L mass transfer and bubble size distribution. This feature may be exploited in design by modifying the hydrophilic or hydrophobic nature of the particles used. Previously we have proposed a

Sulfur turnover and emissions during storage of cattle slurry

DEFF Research Database (Denmark)

Eriksen, Jørgen; Andersen, Astrid J; Poulsen, Henrik Vestergaard

2012-01-01

Slurry acidification using sulfuric acid reduces ammonia emissions but also affects sulfur (S) cycling. Emission of sulfur is a source of malodor and reduces the sulfur fertilizer value of the slurry. We investigated the effect of sulfate and methionine amendments, alone or in combination...

High density submicron magnetoresistive random access memory (invited)

Science.gov (United States)

Tehrani, S.; Chen, E.; Durlam, M.; DeHerrera, M.; Slaughter, J. M.; Shi, J.; Kerszykowski, G.

1999-04-01

Various giant magnetoresistance material structures were patterned and studied for their potential as memory elements. The preferred memory element, based on pseudo-spin valve structures, was designed with two magnetic stacks (NiFeCo/CoFe) of different thickness with Cu as an interlayer. The difference in thickness results in dissimilar switching fields due to the shape anisotropy at deep submicron dimensions. It was found that a lower switching current can be achieved when the bits have a word line that wraps around the bit 1.5 times. Submicron memory elements integrated with complementary metal-oxide-semiconductor (CMOS) transistors maintained their characteristics and no degradation to the CMOS devices was observed. Selectivity between memory elements in high-density arrays was demonstrated.

Experimental investigation of combustion of biomass slurry in an oil fired furnace

Energy Technology Data Exchange (ETDEWEB)

Prakash, S.V. [Mechanical Dept., M.S. Ramaiah Inst. of Tech., Bangalore (India); Shankapal, S.R. [M.S. Ramaiah School of Advanced Studies, Bangalore (India)

2008-07-01

An experimental investigation of combustion of biomass slurry in an oil fired furnace was carried out using pulverized coconut shell (CSP), LDO and water. The effect of equivalence ratio on the slurry composition, calorific value and the effect of exhaust gas percentage are presented. The calorific value of the biomass slurry increases with equivalence ratio initially, attains a peak value and then decreases with the increase in equivalence ratio. It is also observed that with the increase in composition of biomass slurry, the cost of the fuel and the percentage emission of CO decreases. It was found that CSP up to a blend of 20% was more convenient to be used as a slurry fuel in the furnace. (orig.)

Gas migration through cement slurries analysis: A comparative laboratory study

Directory of Open Access Journals (Sweden)

Arian Velayati

2015-12-01

Full Text Available Cementing is an essential part of every drilling operation. Protection of the wellbore from formation fluid invasion is one of the primary tasks of a cement job. Failure in this task results in catastrophic events, such as blow outs. Hence, in order to save the well and avoid risky and operationally difficult remedial cementing, slurry must be optimized to be resistant against gas migration phenomenon. In this paper, performances of the conventional slurries facing gas invasion were reviewed and compared with modified slurry containing special gas migration additive by using fluid migration analyzer device. The results of this study reveal the importance of proper additive utilization in slurry formulations. The rate of gas flow through the slurry in neat cement is very high; by using different types of additives, we observe obvious changes in the performance of the cement system. The rate of gas flow in neat class H cement was reported as 36000 ml/hr while the optimized cement formulation with anti-gas migration and thixotropic agents showed a gas flow rate of 13.8 ml/hr.

Physio-Microstructural Properties of Aerated Cement Slurry for Lightweight Structures

Science.gov (United States)

Salem, Talal; Hamadna, Sameer; Darsanasiri, A. G. N. D.; Soroushian, Parviz; Balchandra, Anagi; Al-Chaar, Ghassan

2018-01-01

Cementitious composites, including ferrocement and continuous fiber reinforced cement, are increasingly considered for building construction and repair. One alternative in processing of these composites is to infiltrate the reinforcement (continuous fibers or chicken mesh) with a flowable cementitious slurry. The relatively high density of cementitious binders, when compared with polymeric binders, are a setback in efforts to introduce cementitious composites as lower-cost, fire-resistant, and durable alternatives to polymer composites. Aeration of the slurry is an effective means of reducing the density of cementitious composites. This approach, however, compromises the mechanical properties of cementitious binders. An experimental program was undertaken in order to assess the potential for production of aerated slurry with a desired balance of density, mechanical performance, and barrier qualities. The potential for nondestructive monitoring of strength development in aerated cementitious slurry was also investigated. This research produced aerated slurries with densities as low as 0.9 g/cm3 with viable mechanical and barrier qualities for production of composites. The microstructure of these composites was also investigated. PMID:29649163

DEVELOPMENT OF A COMPUTATIONAL MULTIPHASE FLOW MODEL FOR FISCHER TROPSCH SYNTHESIS IN A SLURRY BUBBLE COLUMN REACTOR

Energy Technology Data Exchange (ETDEWEB)

Donna Post Guillen; Tami Grimmett; Anastasia M. Gribik; Steven P. Antal

2010-09-01

The Hybrid Energy Systems Testing (HYTEST) Laboratory is being established at the Idaho National Laboratory to develop and test hybrid energy systems with the principal objective to safeguard U.S. Energy Security by reducing dependence on foreign petroleum. A central component of the HYTEST is the slurry bubble column reactor (SBCR) in which the gas-to-liquid reactions will be performed to synthesize transportation fuels using the Fischer Tropsch (FT) process. SBCRs are cylindrical vessels in which gaseous reactants (for example, synthesis gas or syngas) is sparged into a slurry of liquid reaction products and finely dispersed catalyst particles. The catalyst particles are suspended in the slurry by the rising gas bubbles and serve to promote the chemical reaction that converts syngas to a spectrum of longer chain hydrocarbon products, which can be upgraded to gasoline, diesel or jet fuel. These SBCRs operate in the churn-turbulent flow regime which is characterized by complex hydrodynamics, coupled with reacting flow chemistry and heat transfer, that effect reactor performance. The purpose of this work is to develop a computational multiphase fluid dynamic (CMFD) model to aid in understanding the physico-chemical processes occurring in the SBCR. Our team is developing a robust methodology to couple reaction kinetics and mass transfer into a four-field model (consisting of the bulk liquid, small bubbles, large bubbles and solid catalyst particles) that includes twelve species: (1) CO reactant, (2) H2 reactant, (3) hydrocarbon product, and (4) H2O product in small bubbles, large bubbles, and the bulk fluid. Properties of the hydrocarbon product were specified by vapor liquid equilibrium calculations. The absorption and kinetic models, specifically changes in species concentrations, have been incorporated into the mass continuity equation. The reaction rate is determined based on the macrokinetic model for a cobalt catalyst developed by Yates and Satterfield [1]. The

Experimental study on the rheological behaviour of coal ash slurries

Directory of Open Access Journals (Sweden)

Assefa K.M.

2015-12-01

Full Text Available Extensive experimental investigations were carried out to evaluate the rheological behaviour of fly ash (FA slurry without and with the addition of bottom ash (BA and BA slurry without and with the addition of FA. The FA slurries exhibited Bingham behaviour at solid mass concentrations ranging from 60–65% and mixing proportions from 10– 40%. A substantial reduction in yield stress was observed except for mixing proportion of 40% on which the yield stress and viscosity were increased drastically for all solid concentrations. Hence, it can be concluded that the yield stress and viscosity of FA slurry were very much influenced by adding BA up to the mixing proportion of 30%. The rheological behaviour of BA slurries with and without the addition of FA in proportions of 10–50% was investigated and exhibited Newtonian behaviours for solid mass concentrations ranging from 30–50% without and with the addition of FA. The viscosity increases with increasing the solid concentrations and proportion of FA. Based on these experimental data, a correlation was developed to predict the relative viscosity of BA slurries as a function of solid volume fraction and FA mass proportion of 0–50% and the RMSE and R2 values showed good agreement between the experimental and the predicted data.

Laser and Particle Guiding Micro-Elements for Particle Accelerators

CERN Document Server

Plettner, Tomas; Spencer, James; Wisdom, Jeffrey

2005-01-01

Laser driven particle accelerators based on the current generation of lasers will require sub-micron control of the laser field as well as precise beam guiding. Hence the fabrication techniques that allow integrating both elements into an accelerator-on-chip format become critical for the success of such particle accelerators. Micromachining technology for silicon has been shown to be one such feasible technology in PAC2003 but with a variety of complications on the laser side. Fortunately, in recent years the fabrication of transparent ceramics has become an interesting technology that could be applied for laser-particle accelerators in several ways. We discuss this area, its advantages such as the range of materials it provides and various ways to implement it followed by some different test examples that have been considered. One important goal of this approach is an integrated system that could avoid the necessity of having to inject either laser or particle pulses into these structures.

Flash pyrolysis of coal-solvent slurry prepared from the oxidized coal and the coal dissolved in solvent; Ichibu yokaishita sanka kaishitsutan slurry no jinsoku netsubunkai

Energy Technology Data Exchange (ETDEWEB)

Maki, T.; Mae, K.; Okutsu, H.; Miura, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering

1996-10-28

In order to develop a high-efficiency coal pyrolysis method, flash pyrolysis was experimented on slurry prepared by using liquid-phase oxidation reformed coal and a methanol-based solvent mixture. Australian Morwell coal was used for the experiment. The oxidized coal, into which carboxyl groups have been introduced, has the condensation structure relaxed largely, and becomes highly fluid slurry by means of the solvent. Char production can be suppressed by making the oxidation-pretreated coal into slurry, resulting in drastically improved pyrolytic conversion. The slurry was divided into dissolved solution, dried substance, extracted residue, and residual slurry, which were pyrolized independently. The dissolved solution showed very high conversion. Improvement in the conversion is contributed by separating the dissolved substances (coal macromolecules) at molecular levels, coagulating the molecules, suppressing cross-link formation, and reducing molecular weight of the dissolved substances. Oxidized coal can be dissolved to 80% or higher by using several kinds of mixed solvents. As a result of the dissolution, a possibility was suggested on pyrolysis which is easy in handling and high in conversion. 7 refs., 6 figs., 2 tabs.

Survey of state water laws affecting coal slurry pipeline development

Energy Technology Data Exchange (ETDEWEB)

Rogozen, M.B.

1980-11-01

This report summarizes state water laws likely to affect the development of coal slurry pipelines. It was prepared as part of a project to analyze environmental issues related to energy transportation systems. Coal slurry pipelines have been proposed as a means to expand the existing transportation system to handle the increasing coal shipments that will be required in the future. The availability of water for use in coal slurry systems in the coal-producing states is an issue of major concern.

Environmental Consequences of Future Biogas Technologies based on Separated Slurry

DEFF Research Database (Denmark)

Hamelin, Lorie; Wesnæs, Marianne; Wenzel, Henrik

2011-01-01

different slurry separation technologies have been assessed and compared to a business-as-usual reference slurry management scenario. The results show that the environmental benefits of such biogas production are highly dependent upon the efficiency of the separation technology used to concentrate......This consequential life cycle assessment study highlights the key environmental aspects of producing biogas from separated pig and cow slurry, a relatively new but probable scenario for future biogas production, as it avoids the reliance on constrained carbon cosubstrates. Three scenarios involving...... the volatile solids in the solid fraction. The biogas scenario involving the most efficient separation technology resulted in a dry matter separation efficiency of 87% and allowed a net reduction of the global warming potential of 40%, compared to the reference slurry management. This figure comprises...

Effects of different treatments of cattle slurry manure on water-extractable phosphorus

NARCIS (Netherlands)

Chapuis-Lardy, L.; Temminghoff, E.J.M.; Goede, de R.G.M.

2003-01-01

Cattle slurry manure applied to land increases the risk of phosphorus (P) movement to surface waters, which may lead to eutrophication. The water-extractable fraction of P in slurry manure is correlated with P concentration in runoff from soils amended with slurry smanure, and thus is an effective

Submicron hollow spot generation by solid immersion lens and structured illumination

International Nuclear Information System (INIS)

Kim, M-S; Scharf, T; Herzig, H P; Assafrao, A C; Wachters, A J H; Pereira, S F; Urbach, H P; Brun, M; Olivier, S; Nicoletti, S

2012-01-01

We report on the experimental and numerical demonstration of immersed submicron-size hollow focused spots, generated by structuring the polarization state of an incident light beam impinging on a micro-size solid immersion lens (μ-SIL) made of SiO 2 . Such structured focal spots are characterized by a doughnut-shaped intensity distribution, whose central dark region is of great interest for optical trapping of nano-size particles, super-resolution microscopy and lithography. In this work, we have used a high-resolution interference microscopy technique to measure the structured immersed focal spots, whose dimensions were found to be significantly reduced due to the immersion effect of the μ-SIL. In particular, a reduction of 37% of the dark central region was verified. The measurements were compared with a rigorous finite element method model for the μ-SIL, revealing excellent agreement between them. (paper)

A new cement slurry modified with chitosan/alginate interpenetrating networks and hydroxyapatite: structural characteristics after long-term contact with hyper-saline produced water from oil well operations

International Nuclear Information System (INIS)

Santos, Ivory Marcos Gomes dos; Santos, Danilo Oliveira; Cestari, Antonio Reinaldo

2017-01-01

Oil is an important source of energy, mainly in developing countries. Important research has been conducted to find cementing procedures that guarantee safe and cost-effective oil exploration below pre-salt layers. This work aimed to make a new cement paste with cement, seawater, silica, biopolymers (chitosan and sodium alginate) and hydroxyapatite (HA), found in nature. For comparison purposes, slurry without additives was prepared and characterized. The HA used was extracted from fish scales (Cynoscion acoupa) in optimized condition NaOH concentration, temperature and reaction time. Both slurry were prepared with ratios water/cement (w/c) and silica/cement (s/c) equal to 0.50 and 0.35, respectively. The new cement slurry was obtained with proportions of 5% of each biopolymer and HA with respect to the total weight of the cement. In the immersion tests, specimens were immersed in samples of hyper production of saline water by 35°C for 15 days. Thereafter, they were washed, dried and its surface layers were scraped. Before, the resulting materials were characterized. The values of the ratios Ca/Si of new cement slurry (3.38 ± 0.06) were superior compared to standard (2.58 ± 0.05). The new slurry had high thermal stability and low amounts of small crystallite-type portlandite (35.70 nm). Conversely, a slurry standard formed larger crystals of about 50.3 nm. Significantly, after continuous long-term contact of both slurries with hyper-saline produced water from oil well fields operations, in comparison with standard slurry structural characteristics, the new slurry has practically maintained its pristine chemical structure, as well as has shown crystallite-type particles of NaCl and Friedel’s/Kuzel’s salts with lower proportion. The presence of the biopolymers and HA has driven the improved the self-healing properties observed in the new cement slurry. In this first study, the new slurry has shown adequate characteristics to contribute to cost effective and

A new cement slurry modified with chitosan/alginate interpenetrating networks and hydroxyapatite: structural characteristics after long-term contact with hyper-saline produced water from oil well operations

Energy Technology Data Exchange (ETDEWEB)

Santos, Ivory Marcos Gomes dos; Santos, Danilo Oliveira; Cestari, Antonio Reinaldo, E-mail: ivorymarcos@hotmail.com, E-mail: danilo.quimico@yahoo.com.br, E-mail: rcestari@gmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Ciencia dos Materiais; Ribeiro, Joenesson Filip Santos, E-mail: joenesson.joe@hotmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Lab, Materiais e Calorimetria; Alves, Jose do Patrocinio Hora; Ferreira, Angelica Baganha, E-mail: jphalves@uol.com.br, E-mail: angelica.bferreira@itps.se.gov.br [Instituto Tecnologico e de Pesquisas do Estado de Sergipe (ITPS), Aracaju, SE (Brazil)

2017-01-15

Oil is an important source of energy, mainly in developing countries. Important research has been conducted to find cementing procedures that guarantee safe and cost-effective oil exploration below pre-salt layers. This work aimed to make a new cement paste with cement, seawater, silica, biopolymers (chitosan and sodium alginate) and hydroxyapatite (HA), found in nature. For comparison purposes, slurry without additives was prepared and characterized. The HA used was extracted from fish scales (Cynoscion acoupa) in optimized condition NaOH concentration, temperature and reaction time. Both slurry were prepared with ratios water/cement (w/c) and silica/cement (s/c) equal to 0.50 and 0.35, respectively. The new cement slurry was obtained with proportions of 5% of each biopolymer and HA with respect to the total weight of the cement. In the immersion tests, specimens were immersed in samples of hyper production of saline water by 35°C for 15 days. Thereafter, they were washed, dried and its surface layers were scraped. Before, the resulting materials were characterized. The values of the ratios Ca/Si of new cement slurry (3.38 ± 0.06) were superior compared to standard (2.58 ± 0.05). The new slurry had high thermal stability and low amounts of small crystallite-type portlandite (35.70 nm). Conversely, a slurry standard formed larger crystals of about 50.3 nm. Significantly, after continuous long-term contact of both slurries with hyper-saline produced water from oil well fields operations, in comparison with standard slurry structural characteristics, the new slurry has practically maintained its pristine chemical structure, as well as has shown crystallite-type particles of NaCl and Friedel’s/Kuzel’s salts with lower proportion. The presence of the biopolymers and HA has driven the improved the self-healing properties observed in the new cement slurry. In this first study, the new slurry has shown adequate characteristics to contribute to cost effective and

Seasonal variations of ultra-fine and submicron aerosols in Taipei, Taiwan: implications for particle formation processes in a subtropical urban area

Directory of Open Access Journals (Sweden)

H. C. Cheung

2016-02-01

Full Text Available The aim of this study is to investigate the seasonal variations in the physicochemical properties of atmospheric ultra-fine particles (UFPs, d ≤ 100 nm and submicron particles (PM1, d ≤ 1 µm in an east Asian urban area, which are hypothesized to be affected by the interchange of summer and winter monsoons. An observation experiment was conducted at TARO (Taipei Aerosol and Radiation Observatory, an urban aerosol station in Taipei, Taiwan, from October 2012 to August 2013. The measurements included the mass concentration and chemical composition of UFPs and PM1, as well as the particle number concentration (PNC and the particle number size distribution (PSD with size range of 4–736 nm. The results indicated that the mass concentration of PM1 was elevated during cold seasons with a peak level of 18.5 µg m−3 in spring, whereas the highest concentration of UFPs was measured in summertime with a mean of 1.64 µg m−3. Moreover, chemical analysis revealed that the UFPs and PM1 were characterized by distinct composition; UFPs were composed mostly of organics, whereas ammonium and sulfate were the major constituents of PM1. The seasonal median of total PNCs ranged from 13.9  ×  103 cm−3 in autumn to 19.4  ×  103 cm−3 in spring. Median concentrations for respective size distribution modes peaked in different seasons. The nucleation-mode PNC (N4 − 25 peaked at 11.6  ×  103 cm−3 in winter, whereas the Aitken-mode (N25 − 100 and accumulation-mode (N100 − 736 PNC exhibited summer maxima at 6.0  ×  103 and 3.1  ×  103 cm−3, respectively. The change in PSD during summertime was attributed to the enhancement in the photochemical production of condensable organic matter that, in turn, contributed to the growth of aerosol particles in the atmosphere. In addition, clear photochemical production of particles was observed, mostly in the summer season

Coal slurries: An environmental bonus?

International Nuclear Information System (INIS)

Basta, N.; Moore, S.; Ondrey, G.

1994-01-01

Developers and promoters of coal-water slurries and similar CWF (coal-water fuel) technologies have had a hard time winning converts since they unveiled their first commercial processes in the 1970s. The economic appeal of such processes, marginal at best, varies with the price of oil. Nevertheless, the technology is percolating, as geopolitics and environmental pressures drive new processes. Such fuels are becoming increasingly important to coal-rich, oil-poor nations such as China, as they attempt to build an onshore fuel supply. Meanwhile, improvements are changing the way coal-fired processes are viewed. Where air pollution regulations once discouraged the use of coal fuels, new coal processes have been developed that cut nitrous oxides (NOx) emissions and provide a use for coal fines, previously viewed as waste. The latest developments in the field were all on display at the 19th International Technical Conference on Coal Utilization and Fuel Systems, held in Clearwater, Fla., on March 21--24. At this annual meeting, sponsored by the Coal and Slurry Technology Association, (Washington, D.C.) and the Pittsburgh Energy Technology Center of the US Dept. of Energy (PETC), some 200 visitors from around the work gathered to discuss the latest developments in coal slurry utilization--new and improved processes, and onstream plants. This paper presents highlights from the conference

Slurry explosive containing an improved thickening agent

Energy Technology Data Exchange (ETDEWEB)

Wakazono, Y.; Otsuka, Y.

1970-08-18

A slurry explosive having stable physical properties and a thickening agent which when blended with a slurry explosive, maintains it in a uniform and stable state as a good suspended dispersion condition over a long period of time, are described. The slurry explosive has a composition consisting essentially of ammonium nitrate, or a mixture of ammonium nitrate and an alkali metal nitrate, or a mixture of ammonium nitrate and an alkaline earth metal nitrate, or a mixture of ammonium nitrate and an alkali metal nitrate and an alkaline earth metal nitrate, at least one member selected from the group consisting of 2,4,6-trinitrotoluene, aluminum, smokeless powder and fuels, and water, 0.1 to 2.0% guar gum, not more than 0.3% of a borate or borates, and/or not more than 20% of hexamethylene tetramine, and 0.02 to 2.0% of an antimony compound or compounds, all percents being by weight. (6 claims)

ADVANCED DIAGNOSTIC TECHNIQUES FOR THREE-PHASE SLURRY BUBBLE COLUMN REACTORS (SBCR)

Energy Technology Data Exchange (ETDEWEB)

M.H. Al-Dahhan; M.P. Dudukovic; L.S. Fan

2001-07-25

This report summarizes the accomplishment made during the second year of this cooperative research effort between Washington University, Ohio State University and Air Products and Chemicals. The technical difficulties that were encountered in implementing Computer Automated Radioactive Particle Tracking (CARPT) in high pressure SBCR have been successfully resolved. New strategies for data acquisition and calibration procedure have been implemented. These have been performed as a part of other projects supported by Industrial Consortium and DOE via contract DE-2295PC95051 which are executed in parallel with this grant. CARPT and Computed Tomography (CT) experiments have been performed using air-water-glass beads in 6 inch high pressure stainless steel slurry bubble column reactor at selected conditions. Data processing of this work is in progress. The overall gas holdup and the hydrodynamic parameters are measured by Laser Doppler Anemometry (LDA) in 2 inch slurry bubble column using Norpar 15 that mimic at room temperature the Fischer Tropsch wax at FT reaction conditions of high pressure and temperature. To improve the design and scale-up of bubble column, new correlations have been developed to predict the radial gas holdup and the time averaged axial liquid recirculation velocity profiles in bubble columns.

Life cycle assessment of biogas from separated slurry

Energy Technology Data Exchange (ETDEWEB)

Hamelin, L.; Wesnaes, M.; Wenzel, H. (Univ. of Southern Denmark, Odense (Denmark)); Molt Petersen, B. (Aarhus Univ.. Faculty of Agricultural Sciences, Aarhus (Denmark))

2010-07-01

The environmental aspects of biogas production based on pre-treated slurry from fattening pigs and dairy cows have been investigated in a life cycle perspective. The pre-treatment consists of concentrating the slurry using a separation technology. Significant environmental benefits, compared to the status quo slurry management, can be obtained for both pig and cow slurry, especially regarding reductions of the contributions to global warming, but the results depend to a large extent on the efficiency of the separation technology. Adding separation after the biogas plant can contribute to a more efficient management of the phosphorus, and this has also been investigated. Based on the results of the study it can be concluded that: 1) The environmental benefits of biogas from separated slurry are very dependent upon the separation efficiency (for carbon, nitrogen and phosphorous). This particularly applies for carbon, as the separation efficiency defines the extent to which the degradable carbon contained in the slurry is transferred to the biogas plant. Efficient separation can be obtained by using polymer, but also by using a suitable separation technology. It could be mentioned that the decanter centrifuge used has a rather high efficiency of transferring volatile solids (VS) to the fibre fraction also without the use of polymer. 2) Biogas production from separated slurry can lead to significant reductions in the contributions to global warming, provided that the 'best available technologies' described in the report are used. That includes, among others: - a covered and short time storage of the fibre fraction before entering the biogas plant, - a 2-step biogas production where the post-digestion tank is covered with air-tight cover, - a covered storage of the degassed fibre fraction The benefits are also highly dependent upon the source of energy substituted by the biogas. 3) Based on evidences from reviewed studies, the cationic polyacrylamide polymer

Computational Modelling of Gas-Particle Flows with Different Particle Morphology in the Human Nasal Cavity

Directory of Open Access Journals (Sweden)

Kiao Inthavong

2009-01-01

Full Text Available This paper summarises current studies related to numerical gas-particle flows in the human nasal cavity. Of interest are the numerical modelling requirements to consider the effects of particle morphology for a variety of particle shapes and sizes such as very small particles sizes (nanoparticles, elongated shapes (asbestos fibres, rough shapes (pollen, and porous light density particles (drug particles are considered. It was shown that important physical phenomena needed to be addressed for different particle characteristics. This included the Brownian diffusion for submicron particles. Computational results for the nasal capture efficiency for nano-particles and various breathing rates in the laminar regime were found to correlate well with the ratio of particle diffusivity to the breathing rate. For micron particles, particle inertia is the most significant property and the need to use sufficient drag laws is important. Drag correlations for fibrous and rough surfaced particles were investigated to enable particle tracking. Based on the simulated results, semi-empirical correlations for particle deposition were fitted in terms of Peclet number and inertial parameter for nanoparticles and micron particles respectively.

Enhancing protein to extremely high content in photosynthetic bacteria during biogas slurry treatment.

Science.gov (United States)

Yang, Anqi; Zhang, Guangming; Meng, Fan; Lu, Pei; Wang, Xintian; Peng, Meng

2017-12-01

This work proposed a novel approach to achieve an extremely high protein content in photosynthetic bacteria (PSB) using biogas slurry as a culturing medium. The results showed the protein content of PSB could be enhanced strongly to 90% in the biogas slurry, which was much higher than reported microbial protein contents. The slurry was partially purified at the same time. Dark-aerobic was more beneficial than light-anaerobic condition for protein accumulation. High salinity and high ammonia of the biogas slurry were the main causes for protein enhancement. In addition, the biogas slurry provided a good buffer system for PSB to grow. The biosynthesis mechanism of protein in PSB was explored according to theoretical analysis. During biogas slurry treatment, the activities of glutamate synthase and glutamine synthetase were increased by 26.55%, 46.95% respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

Steam Explosions in Slurry-fed Ceramic Melters

Energy Technology Data Exchange (ETDEWEB)

Carter, J.T.

2001-03-28

This report assesses the potential and consequences of a steam explosion in Slurry Feed Ceramic Melters (SFCM). The principles that determine if an interaction is realistically probable within a SFCM are established. Also considered are the mitigating effects due to dissolved, non-condensable gas(es) and suspended solids within the slurry feed, radiation, high glass viscosity, and the existence of a cold cap. The report finds that, even if any explosion were to occur, however, it would not be large enough to compromise vessel integrity.

Qualification of the Lasentec M600P Particle Size Analyzer and the Red Valve Model 1151 Pressure Sensor

International Nuclear Information System (INIS)

JR Bontha; NG Colton; EA Daymo; TD Hylton; CK Bayne; TH May

2000-01-01

The Lasentec M600 in-line particle size analyzer was installed at Oak Ridge National Laboratory (ORNL) in August 1998 to support retrieval of the Gunite and Associated Tanks (GAAT). Before installation at ORNL, the sensor underwent validation testing at the Pacific Northwest National Laboratory (PNNL) Instrument Validation facility. Mechanically, the instrument worked well during validation testing and met all expectations. Operationally, much was learned about optimum ways to display and interpret the data. Slurry samples taken during the in-line tests at PNNL were shipped to the vendor for analysis with a benchtop Lasentec sensor. These experiments were performed to determine if off-line analyses yield particle size distributions similar to those generated by the in-line sensor. It was determined that the Lasentec sensor measures repeatable chord lengths as long as particles are ''presenter'' to the sensor window the same way. After the initial non-radioactive simulant testing at PNNL, the instrument was shipped for radioactive validation and acceptance testing in the Slurry Monitoring Test System (SMTS) connected to the Tank W-9 of the GAATs at ORNL. For all acceptance tests conducted at ORNL, the variation in the chord length distribution and the total particle count corresponded very well with the slurry density data as determined using an in-line Promass 63M Coriolis meter. Based on the performance results obtained, the Lasentec M600P FBRM is expected to meet the requirements for measuring the particle size distribution during the slurry transfer operations at Hanford and the Oak Ridge GAAT remediation project. The Red Valve pressure sensor was endorsed at the Hanford Site following instrument validation tests at PNNL and is currently in operation in the Tank 241-C-106 pump pit. While this instrument measures pressure within a transfer line, this type of pressure sensor could be configured to measure pressure drop over time. In turn, the status of a slurry

A Qualitative Investigation of Deposition Velocities of a Non-Newtonian Slurry in Complex Pipeline Geometries

Energy Technology Data Exchange (ETDEWEB)

Yokuda, Satoru T.; Poloski, Adam P.; Adkins, Harold E.; Casella, Andrew M.; Hohimer, Ryan E.; Karri, Naveen K.; Luna, Maria; Minette, Michael J.; Tingey, Joel M.

2009-05-11

The External Flowsheet Review Team (EFRT) has identified the issues relating to the Waste Treatment and Immobilization Plant (WTP) pipe plugging. Per the review’s executive summary, “Piping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging.” To evaluate the potential for plugging, testing was performed to determine critical velocities for the complex WTP piping layout. Critical velocity is defined as the point at which a moving bed of particles begins to form on the pipe bottom during slurry-transport operations. Pressure drops across the fittings of the test pipeline were measured with differential pressure transducers, from which the critical velocities were determined. A WTP prototype flush system was installed and tested upon the completion of the pressure-drop measurements. We also provide the data for the overflow relief system represented by a WTP complex piping geometry with a non-Newtonian slurry. A waste simulant composed of alumina (nominally 50 μm in diameter) suspended in a kaolin clay slurry was used for this testing. The target composition of the simulant was 10 vol% alumina in a suspending medium with a yield stress of 3 Pa. No publications or reports are available to confirm the critical velocities for the complex geometry evaluated in this testing; therefore, for this assessment, the results were compared to those reported by Poloski et al. (2008) for which testing was performed for a straight horizontal pipe. The results of the flush test are compared to the WTP design guide 24590-WTP-GPG-M-0058, Rev. 0 (Hall 2006) in an effort to confirm flushing-velocity requirements.

A Qualitative Investigation of Deposition Velocities of a Non-Newtonian Slurry in Complex Pipeline Geometries

International Nuclear Information System (INIS)

Yokuda, Satoru T.; Poloski, Adam P.; Adkins, Harold E.; Casella, Andrew M.; Hohimer, Ryan E.; Karri, Naveen K.; Luna, Maria; Minette, Michael J.; Tingey, Joel M.

2009-01-01

The External Flowsheet Review Team (EFRT) has identified the issues relating to the Waste Treatment and Immobilization Plant (WTP) pipe plugging. Per the review's executive summary, ''Piping that transports slurries will plug unless it is properly designed to minimize this risk. This design approach has not been followed consistently, which will lead to frequent shutdowns due to line plugging.'' To evaluate the potential for plugging, testing was performed to determine critical velocities for the complex WTP piping layout. Critical velocity is defined as the point at which a moving bed of particles begins to form on the pipe bottom during slurry-transport operations. Pressure drops across the fittings of the test pipeline were measured with differential pressure transducers, from which the critical velocities were determined. A WTP prototype flush system was installed and tested upon the completion of the pressure-drop measurements. We also provide the data for the overflow relief system represented by a WTP complex piping geometry with a non-Newtonian slurry. A waste simulant composed of alumina (nominally 50 (micro)m in diameter) suspended in a kaolin clay slurry was used for this testing. The target composition of the simulant was 10 vol% alumina in a suspending medium with a yield stress of 3 Pa. No publications or reports are available to confirm the critical velocities for the complex geometry evaluated in this testing; therefore, for this assessment, the results were compared to those reported by Poloski et al. (2008) for which testing was performed for a straight horizontal pipe. The results of the flush test are compared to the WTP design guide 24590-WTP-GPG-M-0058, Rev. 0 (Hall 2006) in an effort to confirm flushing-velocity requirements.

Interaction, transformation and toxicity assessment of particles and additives used in the semiconducting industry.

Science.gov (United States)

Dumitrescu, Eduard; Karunaratne, Dinusha P; Babu, S V; Wallace, Kenneth N; Andreescu, Silvana

2018-02-01

Chemical mechanical planarization (CMP) is a widely used technique for the manufacturing of integrated circuit chips in the semiconductor industry. The process generates large amounts of waste containing engineered particles, chemical additives, and chemo-mechanically removed compounds. The environmental and health effects associated with the release of CMP materials are largely unknown and have recently become of significant concern. Using a zebrafish embryo assay, we established toxicity profiles of individual CMP particle abrasives (SiO 2 and CeO 2 ), chemical additives (hydrogen peroxide, proline, glycine, nicotinic acid, and benzotriazole), as well as three model representative slurries and their resulting waste. These materials were characterized before and after use in a typical CMP process in order to assess changes that may affect their toxicological profile and alter their surface chemistry due to polishing. Toxicity outcome in zebrafish is discussed in relation with the physicochemical characteristics of the abrasive particles and with the type and concentration profile of the slurry components pre and post-polishing, as well as the interactions between particle abrasives and additives. This work provides toxicological information of realistic CMP slurries and their polishing waste, and can be used as a guideline to predict the impact of these materials in the environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Prospects for coal slurry pipelines in California

Science.gov (United States)

Lynch, J. F.

1978-01-01

The coal slurry pipeline segment of the transport industry is emerging in the United States. If accepted it will play a vital role in meeting America's urgent energy requirements without public subsidy, tax relief, or federal grants. It is proven technology, ideally suited for transport of an abundant energy resource over thousands of miles to energy short industrial centers and at more than competitive costs. Briefly discussed are the following: (1) history of pipelines; (2) California market potential; (3) slurry technology; (4) environmental benefits; (5) market competition; and (6) a proposed pipeline.

Experimental and numerical studies on laser-based powder deposition of slurry erosion resistant materials

Science.gov (United States)

Balu, Prabu

Slurry erosion (the removal of material caused by the randomly moving high velocity liquid-solid particle mixture) is a serious issue in crude oil drilling, mining, turbines, rocket nozzles, pumps, and boiler tubes that causes excessive downtime and high operating costs as a result of premature part failure. The goal of this research is to enhance the service life of high-value components subjected to slurry erosion by utilizing the concept of functionally graded metal-ceramic composite material (FGMCCM) in which the favorable properties of metal (toughness, ductility, etc.) and ceramic (hardness) are tailored smoothly to improve erosion resistance. Among the potential manufacturing processes, such as the laser-based powder deposition (LBPD), the plasma transferred arc (PTA), and the thermal spray the LBPD process offers good composition and microstructure control with a high deposition rate in producing the FGMCCM. This research focuses on the development of nickel-tungsten carbide (Ni-WC) based FGMCCM using the LBPD process for applications the above mentioned. The LBPD of Ni-WC involves the introduction of Ni and WC powder particle by an inert gas into the laser-formed molten pool at the substrate via nozzles. The LBPD of Ni-WC includes complex multi-physical interactions between the laser beam, Ni-WC powder, substrate, and carrier and shielding gases that are governed by a number of process variables such as laser power, scanning speed, and powder flow rate. In order to develop the best Ni-WC based slurry erosion resistant material using the LBPD process, the following challenges associated with the fabrication and the performance evaluation need to be addressed: 1) flow behavior of the Ni-WC powder and its interaction with the laser, 2) the effect of the process variables, the material compositions, and the thermo-physical properties on thermal cycles, temperature gradient, cooling rate, and residual stress formation within the material and the subsequent

Mobility of Hematite Submicron Particles in Water Solutions of Sugar

International Nuclear Information System (INIS)

Fornal, P.; Stanek, J.

2008-01-01

The mobility of the 100 nm Fe 2 O 3 particles in dense water solutions of sugar (sucrose) was determined from the analysis of the resonance absorption line shape of the Moessbauer spectra recorded in the -5 o C to 40 o C temperature range for different sugar concentrations. The discrepancy between the experimental data and the prediction of the classical theory of Brownian movement are interpreted in the term of the short observation time and the interaction between the solid particles in fluids, which extends in water up to 300 nm. The sedimentation process in the studied colloids was observed. (authors)

Ozone and limonene in indoor air: a source of submicron particle exposure.

Science.gov (United States)

Wainman, T; Zhang, J; Weschler, C J; Lioy, P J

2000-12-01

Little information currently exists regarding the occurrence of secondary organic aerosol formation in indoor air. Smog chamber studies have demonstrated that high aerosol yields result from the reaction of ozone with terpenes, both of which commonly occur in indoor air. However, smog chambers are typically static systems, whereas indoor environments are dynamic. We conducted a series of experiments to investigate the potential for secondary aerosol in indoor air as a result of the reaction of ozone with d-limonene, a compound commonly used in air fresheners. A dynamic chamber design was used in which a smaller chamber was nested inside a larger one, with air exchange occurring between the two. The inner chamber was used to represent a model indoor environment and was operated at an air exchange rate below 1 exchange/hr, while the outer chamber was operated at a high air exchange rate of approximately 45 exchanges/hr. Limonene was introduced into the inner chamber either by the evaporation of reagent-grade d-limonene or by inserting a lemon-scented, solid air freshener. A series of ozone injections were made into the inner chamber during the course of each experiment, and an optical particle counter was used to measure the particle concentration. Measurable particle formation and growth occurred almost exclusively in the 0.1-0.2 microm and 0.2-0.3 microm size fractions in all of the experiments. Particle formation in the 0.1-0.2 microm size range occurred as soon as ozone was introduced, but the formation of particles in the 0.2-0.3 microm size range did not occur until at least the second ozone injection occurred. The results of this study show a clear potential for significant particle concentrations to be produced in indoor environments as a result of secondary particle formation via the ozone-limonene reaction. Because people spend the majority of their time indoors, secondary particles formed in indoor environments may make a significant contribution to

Electron beam fabrication of a microfluidic device for studying submicron-scale bacteria

Science.gov (United States)

2013-01-01

Background Controlled restriction of cellular movement using microfluidics allows one to study individual cells to gain insight into aspects of their physiology and behaviour. For example, the use of micron-sized growth channels that confine individual Escherichia coli has yielded novel insights into cell growth and death. To extend this approach to other species of bacteria, many of whom have dimensions in the sub-micron range, or to a larger range of growth conditions, a readily-fabricated device containing sub-micron features is required. Results Here we detail the fabrication of a versatile device with growth channels whose widths range from 0.3 μm to 0.8 μm. The device is fabricated using electron beam lithography, which provides excellent control over the shape and size of different growth channels and facilitates the rapid-prototyping of new designs. Features are successfully transferred first into silicon, and subsequently into the polydimethylsiloxane that forms the basis of the working microfluidic device. We demonstrate that the growth of sub-micron scale bacteria such as Lactococcus lactis or Escherichia coli cultured in minimal medium can be followed in such a device over several generations. Conclusions We have presented a detailed protocol based on electron beam fabrication together with specific dry etching procedures for the fabrication of a microfluidic device suited to study submicron-sized bacteria. We have demonstrated that both Gram-positive and Gram-negative bacteria can be successfully loaded and imaged over a number of generations in this device. Similar devices could potentially be used to study other submicron-sized organisms under conditions in which the height and shape of the growth channels are crucial to the experimental design. PMID:23575419

Transport of Cryptosporidium parvum oocysts in soil columns following applications of raw and separated liquid slurry

DEFF Research Database (Denmark)

Petersen, Heidi Huus; Enemark, Heidi L.; Olsen, Annette

2012-01-01

to determine the effectiveness of different slurry separation technologies to remove oocysts and other pathogens, as well as whether application of separated liquid slurry to agricultural land may represent higher risks for ground water contamination as compared to application of raw slurry.......The potential for transport of viable Cryptosporidium parvum oocysts through soil to land drains and groundwater was studied using simulated rainfall and intact soil columns which were applied raw slurry or separated liquid slurry. Following irrigation and weekly samplings over a four week period......, C. parvum oocysts were detected from all soil columns regardless of slurry type and application method although recovery rates were low (liquid slurry leached 73% and 90% more oocysts compared with columns with injected and surface applied raw slurry, respectively...

Influence of glass particle size of resin cements on bonding to glass ceramic: SEM and bond strength evaluation.

Science.gov (United States)

Valentini, Fernanda; Moraes, Rafael R; Pereira-Cenci, Tatiana; Boscato, Noéli

2014-05-01

This study investigated the effect of the filler particle size (micron or submicron) of experimental resin cements on the microtensile bond strength to a glass-ceramic pretreated with hydrofluoric acid (HFA) etching or alumina airborne-particle abrasion (AA). Cements were obtained from a Bis-GMA/TEGDMA mixture filled with 60 mass% micron-sized (1 ± 0.2 µm) or submicron-sized (180 ± 30 µm) Ba-Si-Al glass particles. Ceramic blocks (PM9; VITA) were treated with 10% HFA for 60 s or AA for 15 s. Silane and adhesive were applied. Ceramic blocks were bonded to resin composite blocks (Z250; 3M ESPE) using one of the cements. Bonded specimens were sectioned into beams (n = 20/group) and subjected to microtensile bond strength tests. Data were analyzed using ANOVA and Student-Newman-Keuls' tests (5%). Failure modes were classified under magnification. Morphologies of the treated ceramic surfaces and bonded interfaces were evaluated by scanning electron microscopy. The HFA-submicron group had lower bond strengths than the other groups. All AA-submicron specimens debonded prematurely. Mixed failures were predominant for HFA groups, whereas interfacial failures predominated for AA groups. SEM revealed a honeycomb-like aspect in the HFA-treated ceramic, whereas the AA-treated groups showed an irregular retentive pattern. Continuity of cement infiltration along the bonded interface was more uniform for HFA-treated compared to AA-treated specimens. Cracks toward the bulk of the ceramic were observed in AA-treated specimens. Particle size significantly influenced the ceramic bond strength, whereas surface treatment had a minor effect. Copyright © 2014 Wiley Periodicals, Inc.

Predicting wear of hydrotransport pipelines in oil sand slurries

Energy Technology Data Exchange (ETDEWEB)

Been, J.; Lu, B.; Wolodko, J. [Alberta Research Council, Edmonton, AB (Canada); Kiel, D. [Coanda Research and Development Corp., Burnaby, BC (Canada)

2008-07-01

An overview of erosion and corrosion methods and techniques was presented. Wear to pipelines is influenced by slurry flow and chemistry; solids loading; and electrochemical interactions. While several experimental techniques have been developed to rank the performance of different pipeline materials, experiments do not currently provide accurate quantitative prediction of pipeline wear in the field. Rotating cylinder electrodes (RCE) and jet impingement methods are used to study the effect of flow velocity on corrosion rate. Slurry pot erosion-corrosion testers are used to rank materials for use in more dilute, less turbulent slurries. Coriolois slurry erosion testers are used to rank the erosion resistance of different pipeline materials. A pilot-scale flow loop is now being constructed by the Alberta Research Council (ARC) in order to replicate wet erosion phenomena in oil sands applications. The flow loop will be used to simulate the field conditions of oil sands pipelines and develop predictive wear data and models. Coulombic shear stress and characteristic wall velocities have been determined using a 2-layer model designed to represent flow as 2 distinct layers. To date, the flow loop pilot study has demonstrated that wear rates in smaller diameter flow loops are not significantly different than larger diameter field installations. Preliminary calculations have demonstrated that the flow loop can be used to accurately simulate the hydrodynamics and wear typically experienced in field slurry flows. 67 refs., 2 tabs., 7 figs.

A novel design of submicron thin film point contacts

International Nuclear Information System (INIS)

Koch, H.

1986-01-01

A thin film point contact design applicable to SIS-, SNS-, and microbridge-type Josephson junctions is presented, which offers potentially advanced junction characteristics (low capacitance, low stray inductance, increased quasi-particle resistance). The design philosophy is based on the fact that a point contact results if two planes having a common symmetry axis but oriented perpendicular to each other are brought into contact with each other. For the case of thin films, instead of two-dimensional planes, the cross section of the resulting ''point''-contact is defined by the thicknesses of the two thin films. Film thicknesses can be controlled much more precisely than lateral dimensions created by lithography. Hence, submicron junction geometries can be achieved using only conventional fabrication techniques. Following this idea, Josephson weak links of the ultrashort microbridge-type have been fabricated by an all-Nb technique having a 0.3-μm X 0.2-μm cross section with a R /SUB q/ I /SUB c/ product (R /SUB q/ = quasiparticle resistance, I /SUB c/ = critical current) of more than 20 mV

On the Accelerated Settling of Fine Particles in a Bidisperse Slurry

Directory of Open Access Journals (Sweden)

Leonid L. Minkov

2015-01-01

Full Text Available An estimation of increasing the volume average sedimentation velocity of fine particles in bidisperse suspension due to their capturing in the circulation zone formed in the laminar flow of incompressible viscous fluid around the spherical coarse particle is proposed. The estimation is important for an explanation of the nonmonotonic shape of the separation curve observed for hydrocyclones. The volume average sedimentation velocity is evaluated on the basis of a cellular model. The characteristic dimensions of the circulation zone are obtained on the basis of a numerical solution of Navier-Stokes equations. Furthermore, these calculations are used for modelling the fast sedimentation of fine particles during their cosedimentation in bidisperse suspension. It was found that the acceleration of sedimentation of fine particles is determined by the concentration of coarse particles in bidisperse suspension, and the sedimentation velocity of fine fraction is proportional to the square of the coarse and fine particle diameter ratio. The limitations of the proposed model are ascertained.

Spread of Hepatitis E virus from pig slurry to the water environment

DEFF Research Database (Denmark)

Krog, Jesper Schak; Forslund, Anita; Breum, Solvej Østergaard

Objectives: Spread of pig slurry as an organic fertilizer is commonly used in Danish agriculture. The slurry is spread untreated so pathogens able to survive in slurry tanks will be widely distributed in the environment. The objective of this study was to examine if hepatitis E virus (HEV), which......), and hence could present a risk for virus transmission to wildlife and shellfish. We tested the presence of HEV in water drained from a test field where slurry from a Danish pig farm had been applied and in mussels from different regions in Denmark with fields in close proximity. Methods: Slurry from......). In addition, samples of water collected from wells located along the field and groundwater. Archived mussels from different regions in Denmark were included in the study. Virus was concentrated from water using Poly Ethylene Glycol precipitation and virus from the digestive tissue of the mussels was extracted...

Fluid dynamic studies for a simulated Melton Valley Storage Tank slurry

International Nuclear Information System (INIS)

Hylton, T.D.; Youngblood, E.L.; Cummins, R.L.

1994-07-01

The Melton Valley Storage Tanks (MVSTs), are used for the collection and storage of remote-handled radioactive liquid wastes. These wastes, which were typically acidic when generated, were neutralized with the addition of sodium hydroxide to protect the storage tanks from corrosion, but this caused the transuranic and heavy metals to precipitate. These wastes will eventually need to be removed from the tanks for ultimate disposal. The objective of the research activities discussed in this report is to support the design of a pipeline transport system between the MVSTs and a treatment facility. Since the wastes in the MVSTs are highly radioactive, a surrogate slurry was developed for this study. Rheological properties of the simulated slurry were determined in a test loop in which the slurry was circulated through three pipeline viscometers of different diameters. Pressure drop data at varying flow rates were used to obtain shear stress and shear rate data. The data were analyzed, and the slurry rheological properties were analyzed by the Power Law model and the Bingham plastic model. The plastic viscosity and yield stress data obtained from the rheological tests were used as inputs for a piping design software package, and the pressure drops predicted by the software compared well with the pressure drop data obtained from the test loop. The minimum transport velocity was determine for the slurry by adding known nominal sizes of glass spheres to the slurry. However, it was shown that the surrogate slurry exhibited hindered settling, which may substantially decrease the minimum transport velocity. Therefore, it may be desired to perform additional tests with a surrogate with a lower concentration of suspended solids to determine the minimum transport velocity

Cattle slurry on grassland - application methods and nitrogen use efficiency

NARCIS (Netherlands)

Lalor, S.T.J.

2014-01-01

Cattle slurry represents a significant resource on grassland-based farming systems. The objective of this thesis was to investigate and devise cattle slurry application methods and strategies that can be implemented on grassland farms to improve the efficiency with which nitrogen (N) in

Dry deposition of submicron atmospheric aerosol over water surfaces in motion

International Nuclear Information System (INIS)

Nevenick, Calec

2013-01-01

Whether by chronic or accidental releases, the impact of a nuclear installation on the environment mainly depends on atmospheric transfers; and as the accidents at Chernobyl and Fukushima show, affect the contamination of surfaces and impacts in the medium and long-term on the environment and the population. In this context, this work focuses on the characterization and modeling of dry deposition of submicron aerosols on liquid surfaces in motion such as rivers. Unlike wet deposition which is conditioned by washout and rainout (rain and clouds), dry deposition is a phenomenon that depends entirely on the characteristics of aerosols, receiving surfaces, and air flow. In practice, the evaluation of dry deposition is based on the estimation of flux modeling as the product of particle concentration and deposition velocity which can vary over several orders of magnitude depending on the receiving surfaces (forest, snow, urban, grassland...). This topic is motivated by the virtual non-existence of studies on the mechanisms of dry deposition on continental water systems such as rivers; and respect for submicron aerosols. They have the lowest deposition efficiencies and filtration and the longer residence time in the atmosphere. In addition, they are potentially the most dangerous to living beings because they can penetrate deeper into the airway. Due to the lack of data on the dry deposition of submicron aerosols on a liquid surface in motion, the approach was based on two axes: 1) the acquisition of experimental deposition velocities and 2) the analysis and interpretation of results through modeling. The experiments were performed with uranine aerosols released into the IOA wind tunnel (Interface Ocean Atmosphere) of the Institute for Research on Non Equilibrium Phenomena which is configured to study the coupling between the air flow and water. These experiments have given many dry deposition velocities for different configurations characterized according to wind

Dry deposition of submicron atmospheric aerosol over water surfaces in motion

International Nuclear Information System (INIS)

Calec, Nevenick

2013-01-01

Whether by chronic or accidental releases, the impact of a nuclear installation on the environment mainly depends on atmospheric transfers; and as the accidents at Chernobyl and Fukushima show, affect the contamination of surfaces and impacts in the medium and long-term on the environment and the population. In this context, this work focuses on the characterization and modeling of dry deposition of submicron aerosols on liquid surfaces in motion such as rivers. Unlike wet deposition which is conditioned by washout and rainout (rain and clouds), dry deposition is a phenomenon that depends entirely on the characteristics of aerosols, receiving surfaces, and air flow. In practice, the evaluation of dry deposition is based on the estimation of flux modeling as the product of particle concentration and deposition velocity which can vary over several orders of magnitude depending on the receiving surfaces (forest, snow, urban, grassland..). This topic is motivated by the virtual non-existence of studies on the mechanisms of dry deposition on continental water systems such as rivers; and respect for submicron aerosols. They have the lowest deposition efficiencies and filtration and the longer residence time in the atmosphere. In addition, they are potentially the most dangerous to living beings because they can penetrate deeper into the airway. Due to the lack of data on the dry deposition of submicron aerosols on a liquid surface in motion, the approach was based on two axes: 1) the acquisition of experimental deposition velocities and 2) the analysis and interpretation of results through modeling. The experiments were performed with uranine aerosols released into the IOA wind tunnel (Interface Ocean Atmosphere) of the Institute for Research on Non Equilibrium Phenomena which is configured to study the coupling between the air flow and water. These experiments have given many dry deposition velocities for different configurations characterized according to wind

Properties of sodium lignosulfonate as dispersant of coal water slurry

International Nuclear Information System (INIS)

Yang, Dongjie; Qiu, Xueqing; Zhou, Mingsong; Lou, Hongming

2007-01-01

In order to use lignosulfonates (a by-product of pulp and paper processes) as an effective dispersant of coal water slurry five purified sodium lignosulfonate (SL) samples with different molecular weights were prepared by fractionation using ultrafiltration and dialysis. The effect of SL on the apparent viscosity of coal water slurry (CWS) was investigated. The adsorption behavior of the SL on the coal water interface has much greater effect on the viscosity of coal water slurry. The higher adsorption amount and compact adsorption film of SL on the coal surface help reduce the viscosity of CWS, and the zeta potential is also an important factor, which is influenced by the sulfonic and carboxyl group contents of the lignosulfonate molecule. Furthermore, the SL with its molecular weight ranging from 10,000 to 30,000 has both a higher adsorbed amount and zeta potential on the coal surface and the best effect on reducing the viscosity of the coal water slurry

Progress on radioactive waste slurry incineration with oxygen and steam

International Nuclear Information System (INIS)

Hoshino, M.; Hayashi, M.; Oda, I.; Nonaka, N.; Kuwayama, K.; Shigeta, T.

1988-01-01

The radioactive waste (radwaste) slurry generated from the nuclear power plant operation, such as spent ion-exchange resins (powdered, bead), fire-retardant oils including phosphate ester and concentrated laundry (by the wet method) liquid waste, has been stored in an untreated condition on the plant site. Recently, since the Condensate Filter Demineralizer (CFD) has been applied in advanced BWR plants, the discharged volume of untreated spent powered resin slurry has been increasing steadily. TEE and NCE have been developing an effective new volume reduction system to treat this radwaste slurry based on an innovative incineration concept. The new system is called the IOS process, the feature of which is incineration with oxygen and steam admixture instead of conventional air. The IOS process, which consists mainly of high heat load incineration with slurry atomization, and combustion gas cooling and condensation by the wet method, has several advantages which are summarized in this paper

Radioactive waste slurry dehydrating and drum filling device

International Nuclear Information System (INIS)

Ichihashi, Toshio; Abe, Kazuaki; Hasegawa, Akira

1981-01-01

Purpose: To obtain a device for simultaneously filling and dehydrating radioactive waste in a waste can without the necessity of a special device for dehydration. Constitution: This device includes a radioactive waste storage tank, a pump for supplying the waste from the tank to a can, a drain tube having a filter at the lower end and installed displaceable in the axial direction of the can, and a drain pump. The slurry stored in the radioactive waste storage tank is supplied by the pump to the can, and the feedwater in the slurry is removed by another pump through a drain pipe having a filter which does not pass solid content from the can. Accordingly, as the slurry is filled in the can, the feedwater contained therein is removed. Consequently, it can simultaneously dehydrate and fill the dehydrated waste in the can. (Yoshihara, H.)

Startup of a Joule-heated glass melter with a graphite slurry

International Nuclear Information System (INIS)

Allen, T.L.; Routt, K.R.; Porter, M.A.

1983-01-01

This paper discusses the theoretical equations and physical and electrical property data of various graphite slurries for starting up a glass melter. An application test is also included to demonstrate the graphite slurry startup technique

Soil-bentonite design mix for slurry cutoff walls used as containment barriers

International Nuclear Information System (INIS)

Rad, N.S.; Bachus, R.C.; Jacobson, B.D.

1995-01-01

In recent years, soil-bentonite slurry cutoff walls have been increasingly used as containment barriers around contaminated soils to impede or, in some cases, nearly eliminate the off-site migration of contaminated ground water or other potentially hazardous liquids. The paper presents the procedures used and the results obtained during an extensive laboratory testing program performed to select varying soil-bentonite slurry mix components for a soil-bentonite slurry cutoff wall constructed around an old landfill at a former oil refinery. The landfill is underlain to varying depths by a coarse granular soils that has been exposed to oil-products. Compatibility of three commercially available bentonite products with the free oil-products and the oil-contaminated ground water found at some locations in the landfill was initially investigated. Based on the test results, one of the bentonite products was selected for use in the soil-bentonite slurry testing program. A clayey soil from a borrow source, potable water from the site, and subsurface soils from the proposed soil-bentonite slurry wall alignment were used to form different soil-bentonite slurry mixes. Slump tests were performed to evaluate the workability of the mixes. Based on the test results, a single mix was selected for further study, including permeability/compatibility testing. The results of the compatibility testing program are presented and discussed in the paper. A specific design mix methodology for evaluating the chemical compatibility of soil-bentonite slurry mixes with permeants is proposed

Gold Wire-networks: Particle Array Guided Evaporation Lithograpy

KAUST Repository

Lone, Saifullah

2015-06-29

We exploited the combination of dry deposition of monolayer of 2D (two dimensional) templates, lift-up transfer of 2D template onto flat surfaces and evaporation lithography [1] to fabricate gold micro- and submicron size wire networks. The approach relies upon the defect free dry deposition of 2D monolayer of latex particles [2] on patterned silicon template and flat PDMS-substrate to create square centered and honey-comb wire networks respectively. The process is followed by lift-up transfer of 2D latex crystal on glass substrate. Subsequently, a small amount of AuNP-suspension is doped on top of the transferred crystal; the suspension is allowed to spread instantaneously and dried at low temperature. The liquid evaporates uniformly to the direction perpendicular to glass substrate. During evaporation, AuNPs are de-wetted along with the movement of liquid to self-assemble in-between the inter-particle spaces and therefore, giving rise to liquid-bridge networks which upon delayed evaporation, transforms into wire networks. The approach is used to fabricate both micro- and submicron wire-networks by simply changing the template dimensions. One of the prime motives behind this study is to down-scale the existing particle array template-based evaporation lithography process to fabricate connected gold wire networks at both micro- and submicron scale. Secondly, the idea of combining the patterned silicon wafer with lifted latex particle template creates an opportunity to clean and res-use the patterned wafer more often and thereby, saving fabrication time and resources. Finally, we illustrated the validity of this approach by creating an easy and high-speed approach to develop gold wire networks on a flexible substrate with a thin deposited adhesive. These advances will not only serve as a platform to scale up the production, but also demonstrated that the fabrication method can produce metallic wire networks of different scale and onto a variety of substrates.

Comparison of catalytic ethylene polymerization in slurry and gas phase

NARCIS (Netherlands)

Daftaribesheli, Majid

2009-01-01

Polyethylene (PE) with the annual consumption of 70 million tones in 2007 is mostly produced in slurry, gas-phase or combination of both processes. This work focuses on a comparison between the slurry and gas phase processes. Why does PE produced in theses two processes can show extremely different

Microencapsulated PCM slurries for heat transfer and energy storage in spacecraft systems

Science.gov (United States)

Colvin, David P.; Mulligan, James C.; Bryant, Yvonne G.; Duncan, John L.; Gravely, Benjamin T.

1992-01-01

The technical feasibility for providing significantly enhanced heat transport and storage as well as improved thermal control has been investigated during several Small Business Innovative Research (SBIR) programs for NASA, the United States Air Force (USAF), and the Strategic Defense Initiative Organization (SDIO) using microencapsulated phase change materials (PCMs) in both aqueous and nonaqueous two-component slurries. In the program for SDIO, novel two-component coolant fluids were prepared and successfully tested at both low (300 K) and intermediate temperatures (460 to 700 K). The two-component fluid slurries of microencapsulated PCMs included organic particles in aqueous and nonaqueous liquids, as well as microencapsulated metals that potentially could be carried by liquid metals or used as powdered heat sinks. Simulation and experimental studies showed that such active cooling systems could be designed and operated with enhancements of heat capacity that exceeded 10 times or 1000 percent that for the base fluid along with significant enhancement in the fluid's heat capacity. Furthermore, this enhancement provided essentially isothermal conditions throughout the pumped primary coolant fluid loop. The results suggest that together with much higher fluid thermal capacity, greater uniformity of temperature is achievable with such fluids, and that significant reductions in pumping power, system size, and system mass are also possible.

Effect of decontamination of planting soil using zeolite slurry that inhibits transition of radioactive cesium from soil to plant bodies

International Nuclear Information System (INIS)

Ikeda, Yutaka; Akita, Hiroyuki; Kikawada, Kazuya

2013-01-01

The accident of Fukushima Daiichi nuclear energy plant by the tsunami resulting from the Great Eastern Japan Earthquake in 2011 caused the radiation contamination of cultivated field in Fukushima Prefecture. Some decontamination techniques such as surface soil grab, deep cultivation, and adding zeolite to the soil were tested in the rice fields of Fukushima Prefecture. Zeolite is usually used in the form of particle. It inhibits the transition of radioactive cesium from soil to plant bodies. Here, zeolite slurry was also used. The inhibition effect of the zeolite slurry was checked not only in the field but also in a laboratory experiment using some vegetables. The laboratory test results proved the effect of decontamination for vegetable; however, the field test showed uncertainness owing to the low passage coefficient of rice. (author)

Design and construction of a deep slurry trench barrier

International Nuclear Information System (INIS)

Deming, P.W.

1997-01-01

A 24 m (80 ft) deep slurry trench surrounding a former chromium manufacturing facility on the Patapsco River in Baltimore, Maryland was constructed in 1995 to contain groundwater and site Soils, and to reduce the volume of groundwater extracted to maintain an inward gradient. In 1992, an embankment made of crushed stone was constructed in the Patapsco River to make land for barrier construction outboard of the bulkheads, and to protect the barrier. Stability of the slurry-supported trench excavation in the embankment required construction from an elevated work platform. An extended reach backhoe was used to excavate the deep slurry trench and to clean the trench bottom. Soil-Bentonite backfill was prepared at a central mixing area and transported by truck to the perimeter barrier. A synthetic membrane was inserted partially into the backfill for connection to a multimedia cap, and for redundancy and erosion control in the tidal zone. Hydraulic testing of the aquitard contained by the barrier demonstrated excellent performance of the barrier and bottom closure. Detailed definition of subsurface conditions and the closure stratum was necessary for the design and successful construction of the barrier, and is recommended for comparable slurry trench construction projects

EVALUATION OF MIXING IN THE SLURRY MIX EVAPORATOR AND MELTER FEED TANK

International Nuclear Information System (INIS)

MARINIK, ANDREW

2004-01-01

The Defense Waste Processing Facility (DWPF) vitrifies High Level radioactive Waste (HLW) currently stored in underground tanks at the Savannah River Site (SRS). The HLW currently being processed is a waste sludge composed primarily of metal hydroxides and oxides in caustic slurry. These slurries are typically characterized as Bingham Plastic fluids. The HLW undergoes a pretreatment process in the Chemical Process Cell (CPC) at DWPF. The processed HLW sludge is then transferred to the Sludge Receipt and Adjustment Tank (SRAT) where it is acidified with nitric and formic acid then evaporated to concentrate the solids. Reflux boiling is used to strip mercury from the waste and then the waste is transferred to the Slurry Mix Evaporator tank (SME). Glass formers are added as a frit slurry to the SME to prepare the waste for vitrification. This mixture is evaporated in the SME to the final concentration target. The frit slurry mixture is then transferred to the Melter Feed Tank (MFT) to be fed to the melter

The effect of arsenic thermal diffusion on the morphology and photoluminescence properties of sub-micron ZnO rods

Energy Technology Data Exchange (ETDEWEB)

Ding Meng [Department of Physics, Jilin University, Changchun 130023 (China); Laboratory of Excited State Processes, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130021 (China); Yao Bin, E-mail: binyao@jlu.edu.c [Department of Physics, Jilin University, Changchun 130023 (China); Zhao Dongxu, E-mail: dxzhao2000@yahoo.com.c [Laboratory of Excited State Processes, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130021 (China); Fang Fang; Shen Dezhen; Zhang Zhenzhong [Laboratory of Excited State Processes, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130021 (China)

2010-05-31

As-doped sub-micron ZnO rods were realized by a simple thermal diffusion process using a GaAs wafer as an arsenic resource. The surface of the sub-micron ZnO rods became rough and the morphology of As-doped sub-micron ZnO rods changed markedly with increasing diffusion temperature. From the results of energy-dispersive X-ray spectroscopy, X-ray diffraction and photoluminescence, arsenic elements were confirmed to be introduced into the sub-micron ZnO rods. The acceptor ionization energy was deduced to be about 110 meV based on the temperature-dependent PL spectra.

The effect of arsenic thermal diffusion on the morphology and photoluminescence properties of sub-micron ZnO rods

International Nuclear Information System (INIS)

Ding Meng; Yao Bin; Zhao Dongxu; Fang Fang; Shen Dezhen; Zhang Zhenzhong

2010-01-01

As-doped sub-micron ZnO rods were realized by a simple thermal diffusion process using a GaAs wafer as an arsenic resource. The surface of the sub-micron ZnO rods became rough and the morphology of As-doped sub-micron ZnO rods changed markedly with increasing diffusion temperature. From the results of energy-dispersive X-ray spectroscopy, X-ray diffraction and photoluminescence, arsenic elements were confirmed to be introduced into the sub-micron ZnO rods. The acceptor ionization energy was deduced to be about 110 meV based on the temperature-dependent PL spectra.

Light emitting diode with high aspect ratio submicron roughness for light extraction and methods of forming

Science.gov (United States)

Li, Ting [Ventura, CA

2011-04-26

The surface morphology of an LED light emitting surface is changed by applying a reactive ion etch (RIE) process to the light emitting surface. High aspect ratio, submicron roughness is formed on the light emitting surface by transferring a thin film metal hard-mask having submicron patterns to the surface prior to applying a reactive ion etch process. The submicron patterns in the metal hard-mask can be formed using a low cost, commercially available nano-patterned template which is transferred to the surface with the mask. After subsequently binding the mask to the surface, the template is removed and the RIE process is applied for time duration sufficient to change the morphology of the surface. The modified surface contains non-symmetric, submicron structures having high aspect ratio which increase the efficiency of the device.

Improving the stability of coal slurries: Quarterly progress report for the period Sep. 15, 1986-Dec. 15, 1986. [Adsorption of gum tragacanth on coal particles

Energy Technology Data Exchange (ETDEWEB)

Fogler, H.S.

1986-01-01

The last quarterly progress report focused on the adsorption study of the polystyrene latex spheres with gum tragacanth (GT), and the adsorption mechanism was found to be hydrophobic rather than electrostatic. Also, the effect of the amount of GT adsorbed, the bulk concentration of GT, incubation time and pH on the stability factor was examined, and the results indicated that the conformation of GT on the surface of latex spheres plays an important role in the stabilization. This report presents the results of the coal-water slurries, mainly focusing on the adsorption study of GT by changing pH and ionic strength. It was found from the experiment in which the ionic strength was changed that the adsorption of GT on the coal particles is hindered by the coulombic repulsion between GT and coal. In addition, the experiment in which pH was changed also indicated that the adsorption mechanism is electrostatic in nature. 7 refs., 2 figs.

Lung clearance of inhaled particles after exposure to carbon black generated from a resuspension system

International Nuclear Information System (INIS)

Lee, P.S.; Gorski, R.A.; Hering, W.E.; Chan, T.L.

1987-01-01

A system to resuspend carbon black particles for providing submicron aerosols for inhalation exposure studies has been developed. The effect of continuous exposure to carbonaceous material (as a surrogate for the carbonaceous particles in diesel exhaust) on the pulmonary clearance of inhaled diesel tracer particles was studied in male Fischer 344 rats. Submicron carbon black particles with a mass median aerodynamic diameter (MMAD) of 0.22 micron and a size distribution similar to that of exhaust particles from a GM 5.7-liter diesel engine were successfully generated and administered to test animals at a nominal concentration of 6 mg/m3 for 20 hr/day, 7 days/week, for periods lasting 1 to 11 weeks. Immediately after the carbon black exposure, test animals were administered 14 C-tagged diesel particles for 45 min in a nose-only chamber. The pulmonary retention of inhaled radioactive tracer particles was determined at preselected time intervals. Based upon the data collected up to 1 year postexposure, prolonged exposure to carbon black particles exhibits a similar inhibitory effect on pulmonary clearance as does prolonged exposure to diesel exhaust with a comparable particulate dose. This observation indicates that the excessive accumulation of carbonaceous material may be the predominant factor affecting lung clearance

REDUCTIVE DEHALOGENATION OF A NITROGEN HETEROCYCLIC HERBICIDE IN ANOXIC AQUIFER SLURRIES

Science.gov (United States)

We studied the metabolic fate of bromacil in anaerobic aquifer slurries held under denitrifying, sulfate-reducing, or methanogenic conditions. Liquid chromatograhy-mass spectrometry of the slurries confirmed that bromacil was debrominated under methanogenic conditions but was not...

Interactions between Soil Texture and Placement of Dairy Slurry Application

DEFF Research Database (Denmark)

Glæsner, Nadia; Kjærgaard, Charlotte; Rubæk, Gitte Holton

2011-01-01

soils. We compared leaching of slurry-applied bromide through intact soil columns (20 cm diam., 20 cm high) of differing textures following surface application or injection of slurry. The volumetric fraction of soil pores >30 μm ranged from 43% in a loamy sand to 28% in a sandy loam and 15% in a loam...... physical protection against leaching of bromide was reflected by 60.2% of the bromide tracer was recovered in the effluent after injection, compared with 80.6% recovery after surface application. No effect of slurry injection was observed in the loamy sand and sandy loam soils. Our findings point to soil...

Indian Creek-AML: Coal slurry reclamation (Kansas case history)

International Nuclear Information System (INIS)

Witthar, S.R.

1998-01-01

Black and Veatch, assisted by Jack Nawrot, developed conceptual and final designs and provided construction assistance to create grasslands and wetlands in order to reclaim an abandoned coal mine for the state of Kansas. The mine included spoils, a coal refuse dump, and slurry pond in the Indian Creek drainage basin in east central Kansas. The Indian Creek flowed from an off-site abandoned mine and through the coal slurry pond where its waters became more polluted. The intent of the reclamation project was to improve water quality and create a wildlife refuge. The coal refuse was covered and seeded with a diversity of vegetation including several grasses and legume. The slurry pond was developed into a series of large wetland cells to improve water quality. Prior to reclamation, the water leaving the site had a typical pH of 3.3, ranging from 2.4 to 5.6, an iron content which typically over 22 mg/L and ranging over 100 mg/L, and contained large amounts of coal slurry. The acid sediment in the slurry killed fish and caused visible damage to a new large concrete box culvert several miles downstream of the site. Post-reclamation water quality leaving the Indian Creek site showed immediate improvement even before vegetation was reestablished. The existing wetland treatment systems have been successfully treating water for over seven years with the pH of the water leaving the wetlands above 7 and soluble iron content less than 1 mg/L. Fish in the constructed wetlands support waterfowl which now nest onsite

Fabrication of sub-micron whole waffer SIS tunnel junctions for millimeter wave mixers

International Nuclear Information System (INIS)

Huq, S.E.; Blamire, M.G.; Evetts, J.E.; Hasko, D.G.; Ahmed, H.

1991-01-01

As a part of a programme for the development of a space-qualified sub-mm-wave mixer operating in the region of one terahertz we have been developing the processes required for the fabrication of submicron whole wafer tunnel junctions. Using the self-aligned whole-wafer process (SAWW) with electron beam lithography we have been able to reliably fabricate high quality (V m > 20 mV) submicron tunnel junctions from whole wafer Nb/AlO x /Nb structures. In particular we show that the junction quality is independent of size down to 0.3 μm 2 junction area. The problems of film stress, anodization, registration for electron beam lithography and lift-off, which limit the yield of good quality sub-micron scale junctions are addressed in this paper

Highly time-resolved chemical characterization of atmospheric submicron particles during 2008 Beijing Olympic Games using an Aerodyne High-Resolution Aerosol Mass Spectrometer

Directory of Open Access Journals (Sweden)

X.-F. Huang

2010-09-01

Full Text Available As part of Campaigns of Air Quality Research in Beijing and Surrounding Region-2008 (CAREBeijing-2008, an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS was deployed in urban Beijing to characterize submicron aerosol particles during the time of 2008 Beijing Olympic Games and Paralympic Games (24 July to 20 September 2008. The campaign mean PM₁ mass concentration was 63.1 ± 39.8 μg m⁻³; the mean composition consisted of organics (37.9%, sulfate (26.7%, ammonium (15.9%, nitrate (15.8%, black carbon (3.1%, and chloride (0.87%. The average size distributions of the species (except BC were all dominated by an accumulation mode peaking at about 600 nm in vacuum aerodynamic diameter, and organics was characterized by an additional smaller mode extending below 100 nm. Positive Matrix Factorization (PMF analysis of the high resolution organic mass spectral dataset differentiated the organic aerosol into four components, i.e., hydrocarbon-like (HOA, cooking-related (COA, and two oxygenated organic aerosols (OOA-1 and OOA-2, which on average accounted for 18.1, 24.4, 33.7 and 23.7% of the total organic mass, respectively. The HOA was identified to be closely associated with primary combustion sources, while the COA mass spectrum and diurnal pattern showed similar characteristics to that measured for cooking emissions. The OOA components correspond to aged secondary organic aerosol. Although the two OOA components have similar elemental (O/C, H/C compositions, they display differences in mass spectra and time series which appear to correlate with the different source regions sampled during the campaign. Back trajectory clustering analysis indicated that the southerly air flows were associated with the highest PM₁ pollution during the campaign. Aerosol particles in southern airmasses were especially rich in inorganic and oxidized organic species. Aerosol particles in northern airmasses

Highly time-resolved chemical characterization of atmospheric submicron particles during 2008 Beijing Olympic Games using an Aerodyne High-Resolution Aerosol Mass Spectrometer

Science.gov (United States)

Huang, X.-F.; He, L.-Y.; Hu, M.; Canagaratna, M. R.; Sun, Y.; Zhang, Q.; Zhu, T.; Xue, L.; Zeng, L.-W.; Liu, X.-G.; Zhang, Y.-H.; Jayne, J. T.; Ng, N. L.; Worsnop, D. R.

2010-09-01

As part of Campaigns of Air Quality Research in Beijing and Surrounding Region-2008 (CAREBeijing-2008), an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) was deployed in urban Beijing to characterize submicron aerosol particles during the time of 2008 Beijing Olympic Games and Paralympic Games (24 July to 20 September 2008). The campaign mean PM1 mass concentration was 63.1 ± 39.8 μg m-3; the mean composition consisted of organics (37.9%), sulfate (26.7%), ammonium (15.9%), nitrate (15.8%), black carbon (3.1%), and chloride (0.87%). The average size distributions of the species (except BC) were all dominated by an accumulation mode peaking at about 600 nm in vacuum aerodynamic diameter, and organics was characterized by an additional smaller mode extending below 100 nm. Positive Matrix Factorization (PMF) analysis of the high resolution organic mass spectral dataset differentiated the organic aerosol into four components, i.e., hydrocarbon-like (HOA), cooking-related (COA), and two oxygenated organic aerosols (OOA-1 and OOA-2), which on average accounted for 18.1, 24.4, 33.7 and 23.7% of the total organic mass, respectively. The HOA was identified to be closely associated with primary combustion sources, while the COA mass spectrum and diurnal pattern showed similar characteristics to that measured for cooking emissions. The OOA components correspond to aged secondary organic aerosol. Although the two OOA components have similar elemental (O/C, H/C) compositions, they display differences in mass spectra and time series which appear to correlate with the different source regions sampled during the campaign. Back trajectory clustering analysis indicated that the southerly air flows were associated with the highest PM1 pollution during the campaign. Aerosol particles in southern airmasses were especially rich in inorganic and oxidized organic species. Aerosol particles in northern airmasses contained a large fraction of primary HOA

Nutrient losses from cattle co-digestate slurry during storage

Directory of Open Access Journals (Sweden)

Francesca Perazzolo

2016-06-01

Full Text Available Among environmental issues related to intensive livestock activity, emissions to air from manure management are of increasing concern. Thus the knowledge of the effect of treatment application on subsequent emissions from manure is required to assess the environment impact of management solutions. This work addresses the effect of anaerobic digestion and phase separation on emissions during storage by studying nitrogen losses from lab-scale stores and field pilot-scale stores of a co-digestate cattle slurry and its respective separated fractions. Lab-scale experiment was carried in temperature-controlled room where each fraction (untreated, separated liquid and separated solid was stored in duplicate for a period of 32 days in 30 L vessel. Pilot-scale experiment was carried out both during the cold season and during warm season for 90 days of storage. In both experimentations samples of the manure were analysed periodically for total Kjeldahl nitrogen (TKN, total ammonia nitrogen, dry matter and volatile solids and pH. These analyses allow estimating nitrogen losses in different storage conditions. Effects of mechanical separation and season were assessed by ANOVA (Wilcoxon test, P<0.05. In temperature controlled conditions nitrogen losses measured account for 13% and 26% of TKN for unseparated and separated slurries respectively. In field conditions during cold season nutrient losses were limited. On average unseparated and separated slurries lost respectively 6.8% and 12.6% of their initial TKN content. Much higher were the TKN losses from the slurries examined in warm season where losses raised up to 40% of the initial TKN content. Generally mechanical separation increases nutrient losses, but the differences were not significant in field conditions. The results highlighted that nutrient losses, in particular the nitrogen ones, can be considerable especially during summer storage. The latter, in case of separated slurries, are mainly related

Improvements of marine clay slurries using chemical–physical combined method (CPCM

Directory of Open Access Journals (Sweden)

Dongqing Wu

2015-04-01

Full Text Available In this paper, the effectiveness, applicability and validity of chemical–physical combined methods (CPCMs for treatment of marine clay (MC slurries were evaluated. The method CPCM1 combines chemical stabilization and vacuum preloading (VP, while CPCM2 is similar to CPCM1 but includes both the application of surcharge and use of geo-bags to provide confinement during surcharge preloading. The key advantage of CPCM2 using geo-bags is that the surcharge can be immediately applied on the chemically stabilized slurries. Two types of geo-bags were investigated under simulated land filling and dyke conditions, respectively. The test results show that the shear strength (cu of treated slurry by CPCM2 is generally much higher than that by CPCM1. Besides, the use of CPCM2 can significantly reduce the treatment time due to the short drainage paths created by geo-bags. Overall, CPCM2 allows faster consolidation and higher preloading that help to achieve higher mechanical properties of the stabilized slurry. There are consistent relationships between cU and water content of slurries treated by CPCM2. Several important observations were also made based on comparisons of experimental data.

Swine slurry application and soil management on double-cropped oat/maize

Directory of Open Access Journals (Sweden)

Marlo Adriano Bison Pinto

2014-06-01

Full Text Available The swine production in southern Brazil is concentrated in small farms that use residues as a nutrient source for crops of economic interest. This study aimed to evaluate the use of swine slurry associated with tillage systems on double-cropped oat/maize. The experiment was carried out in the 2009/2010 and 2010/2011 cropping seasons, in Taquaruçu do Sul, Rio Grande do Sul State, Brazil. The experimental design was randomized blocks in a factorial scheme, with four replications. Treatments consisted of the interaction of four swine slurry doses (no swine slurry, 20 m3 ha-1, 40 m3 ha-1 and 80 m3 ha-1 and mineral fertilization, in three tillage systems (no-tillage, chiseling and chiseling + disking. The swine slurry application on doublecropped oat/maize increased the dry matter and grain yield. The 80 m3 ha-1 dose provided a response statistically similar to the mineral fertilization recommended for maize. The interaction between the 80 m3 ha-1 dose and the immediate incorporation of slurry into the soil reduced N losses by ammonia volatilization, promoting a significant increase in maize grain yield, when grown on a clayish soil.

Repair of Cranial Bone Defects Using rhBMP2 and Submicron Particle of Biphasic Calcium Phosphate Ceramics with Through-Hole

Directory of Open Access Journals (Sweden)

Byung-Chul Jeong

2015-01-01

Full Text Available Recently a submicron particle of biphasic calcium phosphate ceramic (BCP with through-hole (donut-shaped BCP (d-BCP was developed for improving the osteoconductivity. This study was performed to examine the usefulness of d-BCP for the delivery of osteoinductive rhBMP2 and the effectiveness on cranial bone regeneration. The d-BCP was soaked in rhBMP2 solution and then freeze-dried. Scanning electron microscope (SEM, energy dispersive spectroscopy (EDS, and Raman spectroscopy analyses confirmed that rhBMP2 was well delivered onto the d-BCP surface and the through-hole. The bioactivity of the rhBMP2/d-BCP composite was validated in MC3T3-E1 cells as an in vitro model and in critical-sized cranial defects in C57BL/6 mice. When freeze-dried d-BCPs with rhBMP2 were placed in transwell inserts and suspended above MC3T3-E1, alkaline phosphatase activity and osteoblast-specific gene expression were increased compared to non-rhBMP2-containing d-BCPs. For evaluating in vivo effectiveness, freeze-dried d-BCPs with or without rhBMP2 were implanted into critical-sized cranial defects. Microcomputed tomography and histologic analysis showed that rhBMP2-containing d-BCPs significantly enhanced cranial bone regeneration compared to non-rhBMP2-containing control. These results suggest that a combination of d-BCP and rhBMP2 can accelerate bone regeneration, and this could be used to develop therapeutic strategies in hard tissue healing.

Repair of Cranial Bone Defects Using rhBMP2 and Submicron Particle of Biphasic Calcium Phosphate Ceramics with Through-Hole.

Science.gov (United States)

Jeong, Byung-Chul; Choi, Hyuck; Hur, Sung-Woong; Kim, Jung-Woo; Oh, Sin-Hye; Kim, Hyun-Seung; Song, Soo-Chang; Lee, Keun-Bae; Park, Kwang-Bum; Koh, Jeong-Tae

2015-01-01

Recently a submicron particle of biphasic calcium phosphate ceramic (BCP) with through-hole (donut-shaped BCP (d-BCP)) was developed for improving the osteoconductivity. This study was performed to examine the usefulness of d-BCP for the delivery of osteoinductive rhBMP2 and the effectiveness on cranial bone regeneration. The d-BCP was soaked in rhBMP2 solution and then freeze-dried. Scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and Raman spectroscopy analyses confirmed that rhBMP2 was well delivered onto the d-BCP surface and the through-hole. The bioactivity of the rhBMP2/d-BCP composite was validated in MC3T3-E1 cells as an in vitro model and in critical-sized cranial defects in C57BL/6 mice. When freeze-dried d-BCPs with rhBMP2 were placed in transwell inserts and suspended above MC3T3-E1, alkaline phosphatase activity and osteoblast-specific gene expression were increased compared to non-rhBMP2-containing d-BCPs. For evaluating in vivo effectiveness, freeze-dried d-BCPs with or without rhBMP2 were implanted into critical-sized cranial defects. Microcomputed tomography and histologic analysis showed that rhBMP2-containing d-BCPs significantly enhanced cranial bone regeneration compared to non-rhBMP2-containing control. These results suggest that a combination of d-BCP and rhBMP2 can accelerate bone regeneration, and this could be used to develop therapeutic strategies in hard tissue healing.

Improvement in water-slurry circulation at the Chumakovskaya coal preparation plant

Energy Technology Data Exchange (ETDEWEB)

Nabokov, A.K.; Fedotov, B.P.; Mitlash, V.V.

1988-02-01

The Chumakovskaya coal preparation plant (Donetskugleobogashchenie association) was put into operation in 1935. It processes 570 t/h of coal slurry with an ash content of 38.6% and produces grade T coal for coking and power generation. Coal preparation technology used is described. Shortcomings of the system cause 130 kg of high ash slurries to be recirculated per m/sup 3/ of hydrocyclone drain. Mathematical analysis of the present process and of two improved variants is presented. The analysis permits variants for clarification of the recirculated water to be developed and evaluated and the best one to be selected. The optimum variant permits the amount of thin recirculated slurry to be reduced to 48% and the amount of granular slurry to 13%. Implementation of this variant at the Chumakovskaya coal preparation plant will ensure annual savings of 20,000 rubles.

Experimental investigation on TBAB clathrate hydrate slurry flows in a horizontal tube: Forced convective heat transfer behaviors

Energy Technology Data Exchange (ETDEWEB)

Wenji, Song [Guangzhou Institute of Energy Conversion, CAS, No. 2 Nengyuan Road, Tianhe District, Guangzhou 510640 (China); Key Laboratory of Renewable Energy and Gas Hydrate, CAS, No. 2 Nengyuan Road, Tianhe District, Guangzhou 510640 (China); Graduate School of Chinese Academy of Sciences, Beijing 100039 (China); Rui, Xiao; Chong, Huang; Shihui, He; Kaijun, Dong; Ziping, Feng [Guangzhou Institute of Energy Conversion, CAS, No. 2 Nengyuan Road, Tianhe District, Guangzhou 510640 (China); Key Laboratory of Renewable Energy and Gas Hydrate, CAS, No. 2 Nengyuan Road, Tianhe District, Guangzhou 510640 (China)

2009-11-15

Tetra-n-butyl-ammonium bromide (TBAB) clathrate hydrate slurry (CHS) is one kind of secondary refrigerants, which is promising to be applied into air-conditioning or latent-heat transportation systems as a thermal storage or cold carrying medium for energy saving. It is a solid-liquid two phase mixture which is easy to produce and has high latent heat and good fluidity. In this paper, the heat transfer characteristics of TBAB slurry were investigated in a horizontal stainless steel tube under different solid mass fractions and flow velocities with constant heat flux. One velocity region of weakened heat transfer was found. Moreover, TBAB CHS was treated as a kind of Bingham fluids, and the influences of the solid particles, flow velocity and types of flow on the forced convective heat transfer coefficients of TBAB CHS were investigated. At last, criterial correlations of Nusselt number for laminar and turbulent flows in the form of power function were summarized, and the error with experimental results was within {+-}20%. (author)

Microalgal cultivation with biogas slurry for biofuel production.

Science.gov (United States)

Zhu, Liandong; Yan, Cheng; Li, Zhaohua

2016-11-01

Microalgal growth requires a substantial amount of chemical fertilizers. An alternative to the utilization of fertilizer is to apply biogas slurry produced through anaerobic digestion to cultivate microalgae for the production of biofuels. Plenty of studies have suggested that anaerobic digestate containing high nutrient contents is a potentially feasible nutrient source to culture microalgae. However, current literature indicates a lack of review available regarding microalgal cultivation with biogas slurry for the production of biofuels. To help fill this gap, this review highlights the integration of digestate nutrient management with microalgal production. It first unveils the current status of microalgal production, providing basic background to the topic. Subsequently, microalgal cultivation technologies using biogas slurry are discussed in detail. A scale-up scheme for simultaneous biogas upgrade and digestate application through microalgal cultivation is then proposed. Afterwards, several uncertainties that might affect this practice are explored. Finally, concluding remarks are put forward. Copyright © 2016 Elsevier Ltd. All rights reserved.

Surfactant mediated slurry formulations for Ge CMP applications

KAUST Repository

Basim, G. Bahar

2013-01-01

In this study, slurry formulations in the presence of self-assembled surfactant structures were investigated for Ge/SiO2 CMP applications in the absence and presence of oxidizers. Both anionic (sodium dodecyl sulfate-SDS) and cationic (cetyl trimethyl ammonium bromide-C12TAB) micelles were used in the slurry formulations as a function of pH and oxidizer concentration. CMP performances of Ge and SiO2 wafers were evaluated in terms of material removal rates, selectivity and surface quality. The material removal rate responses were also assessed through AFM wear rate tests to obtain a faster response for preliminary analyses. The surfactant adsorption characteristics were studied through surface wettability responses of the Ge and SiO2 wafers through contact angle measurements. It was observed that the self-assembled surfactant structures can help obtain selectivity on the silica/germanium system at low concentrations of the oxidizer in the slurry. © 2013 Materials Research Society.

Biological treatment of soils contaminated with hydrophobic organics using slurry- and solid-phase techniques

Science.gov (United States)

Cassidy, Daniel H.; Irvine, Robert L.

1995-10-01

Both slurry-phase and solid-phase bioremediation are effective ex situ soil decontamination methods. Slurrying is energy intensive relative to solid-phase treatment, but provides homogenization and uniform nutrient distribution. Limited contaminant bioavailability at concentrations above the required cleanup level reduces biodegradation rates and renders solid phase bioremediation more cost effective than complete treatment in a bio-slurry reactor. Slurrying followed by solid-phase bioremediation combines the advantages and minimizes the weaknesses of each treatment method when used alone. A biological treatment system consisting of slurrying followed by aeration in solid phase bioreactors was developed and tested in the laboratory using a silty clay loam contaminated with diesel fuel. The first set of experiments was designed to determine the impact of the water content and mixing time during slurrying on the rate an extent of contaminant removal in continuously aerated solid phase bioreactors. The second set of experiments compared the volatile and total diesel fuel removal in solid phase bioreactors using periodic and continuous aeration strategies. Results showed that slurrying for 1.5 hours at a water content less than saturation markedly increased the rate and extent of contaminant biodegradation in the solid phase bioreactors compared with soil having no slurry pretreatment. Slurrying the soil at or above its saturation moisture content resulted in lengthy dewatering times which prohibited aeration, thereby delaying the onset of biological treatment in the solid phase bioreactors. Results also showed that properly operated periodic aeration can provide less volatile contaminant removal and a grater fraction of biological contaminant removal than continuous aeration.

Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

Science.gov (United States)

Doherty, J.P.; Marek, J.C.

1987-02-25

A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper(II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the original organic compounds, is subsequently blended with high level radioactive sludge land transferred to a vitrification facility for processing into borosilicate glass for long-term storage. 2 figs., 3 tabs.

Novel Translucent and Strong Submicron Alumina Ceramics for Dental Restorations.

Science.gov (United States)

Zhao, M; Sun, Y; Zhang, J; Zhang, Y

2018-03-01

An ideal ceramic restorative material should possess excellent aesthetic and mechanical properties. We hypothesize that the high translucency and strength of polycrystalline ceramics can be achieved through microstructural tailoring. The aim of this study is to demonstrate the superior optical and mechanical properties of a new class of submicron grain-sized alumina ceramics relative to the current state-of-the-art dental ceramic materials. The translucency, the in-line transmission ( T IT ) in particular, of these submicron alumina ceramics has been examined with the Rayleigh-Gans-Debye light-scattering model. The theoretical predictions related very well with the measured T IT values. The translucency parameter ( TP) and contrast ratio ( CR) of the newly developed aluminas were measured with a reflectance spectrophotometer on a black-and-white background. For comparison, the T IT , TP, and CR values for a variety of dental ceramics, mostly measured in-house but also cited from the literature, were included. The flexural strength of the aluminas was determined with the 4-point bending test. Our findings have shown that for polycrystalline alumina ceramics, an average grain size ceramic and zirconias, including the most translucent cubic-containing zirconias. The strength of these submicron grain-sized aluminas was significantly higher than that of the cubic-containing zirconia (e.g., Zpex Smile) and lithia-based glass-ceramics (e.g., IPS e.max CAD HT). A coarse-grained alumina could also reach a translucency level comparable to that of dental porcelain. However, the relatively low strength of this material has limited its clinical indications to structurally less demanding applications, such as orthodontic brackets. With a combined high strength and translucency, the newly developed submicron grain-sized alumina may be considered a suitable material for dental restorations.

Draught requirement of trailing foot and shallow injection equipment for applying slurry to grassland

NARCIS (Netherlands)

Huijsmans, J.F.M.; Hendriks, J.L.G.; Vermeulen, G.D.

1998-01-01

Surface spreading of slurry leads to the inevitable emission of ammonia into the environment. Injection of slurry on grassland reduces these emissions. However, injection of slurry by deep working injector tines with goose foot chisels (wings) requires high draught forces. This type of injection has

Combined slurry and cavitation erosion resistance of surface modified SS410 stainless steel

Science.gov (United States)

Amarendra, H. J.; Pratap, M. S.; Karthik, S.; Punitha Kumara, M. S.; Rajath, H. C.; Ranjith, H.; Shubhatunga, S. V.

2018-03-01

Slurry erosion and combined slurry and cavitation erosion resistance of thermal spray coatings are studied and compared with the as-received martensitic stainless steel material. 70Ni-Cr coatings are deposited on SS 410 material through plasma thermal spray process. The synergy effect of the combined slurry and cavitation erosion resistance of plasma thermal spray coatings were investigated in a slurry pot tester in the presence of bluff bodies known as Cavitation Inducers. Results showed the combined slurry and cavitation erosion resistance of martensitic stainless steel - 410 can be improved by plasma thermal spray coating. It is observed that the plasma spray coated specimens are better erosion resistant than the as- received material, subjected to erosion test under similar conditions. As-received and the surface modified steels are mechanically characterized for its hardness, bending. Morphological studies are conducted through scanning electron microscope.

Synthesis and characterization of cement slurries additives with epoxy resins - kinetics, thermodynamic and calorimetric analysis

International Nuclear Information System (INIS)

Tavares, A.M.G.; Andrade Junior, M.A.S.; Cestari, A.R.; Vieira, E.F.S.

2010-01-01

Cement has been used in the world, presenting a wide versatility. However, due to its chemical nature, it is subject to several types of chemical damages, especially for agents of acidic nature. With the purpose of increase its life-time, new cement slurries have been modified with the addition of specific additives. The objective of this work is to modify cement slurries with epoxy resins, which promote higher resistance of those materials in relation to acid attacks. Three cement slurries were synthesized with epoxy resins and a standard slurries, which was composed by cement and water. After 30 days of hydration, the samples were characterized by XDR, FTIR and thermal analysis (TG and DSC). The hydration processes of the cement slurries were studied by heat-conduction microcalorimetry. A kinetic study of HCl interaction with the new slurries were performed by the batch methodology at 25, 35, 45 e 55 deg C. It was verified that the addition of the polymers delayed the processes of hydration of the slurries, decreasing the flow of heat released as a function of the amount of added resin and, increased the resistance of those slurries to the acid attack. (author)

Laser plasmas as x-ray sources for lithographic imaging of submicron structures

International Nuclear Information System (INIS)

Bijkerk, F.; van Dorssen, G.E.; van der Wiel, M.J.

1988-01-01

Laser radiation can be used efficiently to generate x-rays for lithographic imaging of submicron patterns, e.g., for VLSI device fabrication. Due to their short wavelength and high average power, excimer lasers show much potential for this application. Results are presented of scaling studies for high repetition rate excimer laser application, using the frequency doubled output of a low repetition rate Nd:YAG/Glass laser. Spectral and spatial characteristics of x-ray emission of the laser plasma are shown. The power density in the laser focus was 3 x 10 12 W/cm 2 . With this source Si x-ray masks with submicron Au absorber profiles are imaged into high sensitivity x-ray photoresist. For the exposures 80 laser shots sufficed to yield high quality submicron structures. Extrapolation of the results to a high power excimer laser reduces the exposure time of the photoresists to several seconds, enabling a wafer throughput at an industrial level

A new route for the synthesis of submicron-sized LaB6

International Nuclear Information System (INIS)

Lihong, Bao; Wurentuya,; Wei, Wei; Tegus, O.

2014-01-01

Submicron crystalline LaB 6 has been successfully synthesized by a solid-state reaction of La 2 O 3 with NaBH 4 at 1200 °C. The effects of reaction temperature on the crystal structure, grain size and morphology were investigated by X-ray diffraction, scanning electron microscope and transmission electron microscope. It is found that when the reaction temperature is in the range of 1000–1100 °C, there are ultrafine nanoparticles and nanocrystals that coexist. When the reaction temperature elevated to 1200 °C, the grain morphology transformed from ultrafine nanoparticle to submicron crystals completely. High resolution transmission electron microscope images fully confirm the formation of LaB 6 cubic structure. - Highlights: • Single-phased LaB 6 have been synthesized by a solid-state reaction in a continuous evacuating process. • The reaction temperature has a important effect on the phase composition. • The grain size increase from nano-size to submicron with increasing reaction temperature

Combined on-board hydride slurry storage and reactor system and process for hydrogen-powered vehicles and devices

Science.gov (United States)

Brooks, Kriston P; Holladay, Jamelyn D; Simmons, Kevin L; Herling, Darrell R

2014-11-18

An on-board hydride storage system and process are described. The system includes a slurry storage system that includes a slurry reactor and a variable concentration slurry. In one preferred configuration, the storage system stores a slurry containing a hydride storage material in a carrier fluid at a first concentration of hydride solids. The slurry reactor receives the slurry containing a second concentration of the hydride storage material and releases hydrogen as a fuel to hydrogen-power devices and vehicles.

Transport of Cryptosporidium parvum oocysts in soil columns following applications of raw and separated liquid slurries.

Science.gov (United States)

Petersen, Heidi H; Enemark, Heidi L; Olsen, Annette; Amin, M G Mostofa; Dalsgaard, Anders

2012-09-01

The potential for the transport of viable Cryptosporidium parvum oocysts through soil to land drains and groundwater was studied using simulated rainfall and intact soil columns which were applied raw slurry or separated liquid slurry. Following irrigation and weekly samplings over a 4-week period, C. parvum oocysts were detected from all soil columns regardless of slurry type and application method, although recovery rates were low (vertical distribution of oocysts, with more oocysts recovered from soil columns added liquid slurry irrespective of the irrigation status. Further studies are needed to determine the effectiveness of different slurry separation technologies to remove oocysts and other pathogens, as well as whether the application of separated liquid slurry to agricultural land may represent higher risks for groundwater contamination compared to application of raw slurry.

Relationships among slurry characteristics and gaseous emissions at different types of commercial Spanish pig farms

Energy Technology Data Exchange (ETDEWEB)

Becaccia, A.; Ferrer, P.; Ibañez, M.A.; Estellés, F.; Rodríguez, C.; Moset, V.; Blas, C. de; Calvet, P.; García-Rebollar, P.

2015-07-01

This study aimed to analyse several factors of variation of slurry composition and to establish prediction equations for potential methane (CH4) and ammonia (NH3) emissions. Seventy-nine feed and slurry samples were collected at two seasons (summer and winter) from commercial pig farms sited at two Spanish regions (Centre and Mediterranean). Nursery, growing-fattening, gestating and lactating facilities were sampled. Feed and slurry composition were determined, and potential CH4 and NH3 emissions measured at laboratory. Feed nutrient contents were used as covariates in the analysis. Near infrared reflectance spectroscopy (NIRS) was evaluated as a predicting tool for slurry composition and potential gaseous emissions. A wide variability was found both in feed and slurry composition. Mediterranean farms had a higher pH (p<0.001) and ash (p=0.02) concentration than those located at the Centre of Spain. Also, type of farm affected ether extract content of the slurry (p=0.02), with highest values obtained for the youngest animal facilities. Results suggested a buffer effect of dietary fibre on slurry pH and a direct relationship (p<0.05) with fibre constituents of manure. Dietary protein content did not affect slurry nitrogen content but decreased (p=0.003) total and volatile solids concentration. Prediction models of potential NH3 emissions (R2=0.89) and CH4 yield (R2=0.61) were obtained from slurry composition. Predictions from NIRS showed a high accuracy for most slurry constituents (R2>0.90) and similar accuracy of prediction of potential NH3 and CH4 emissions (R2=0.84 and 0.68, respectively) to models using slurry characteristics, which can be of interest to estimate emissions from commercial farms and establish mitigation strategies or optimize biogas production. (Author)

An experimental study of the latent functionally thermal fluid with micro-encapsulated phase change material particles flowing in microchannels

International Nuclear Information System (INIS)

Wang, Yan; Chen, Zhenqian; Ling, Xiang

2016-01-01

Graphical abstract: Fig. 1. Relationship between Nu and Re for MEPCM slurry with various particle volume fractions. The interrupt of the well dispersed particles would destroy the thermal boundary layer and reduces its thickness, resulting in large Nusselt number for the suspension with 2% volume fraction of MEPCM. Large amount of heat could be absorbed and transferred rapidly during MEPCM melting process, which would result in remarkable increase of Nusselt number. The heat transfer performance of latent thermal fluid would be enhanced as 1.34 times of that of pure water. With smaller particle volume fraction (1% in this context), phase change occurs at lower temperature and more intensive heat flux is required for higher concentration suspension to induce the phase change occurrence, which is useful for application of the thermal management design. - Highlights: • The experiments of latent fluid flowing in parallel microchannels were conducted. • The performance of water with well dispersed micro-encapsulated phase change material particles was examined. • The Nusselt number of MEPCM slurry could achieve 1.36 times as that of pure water. - Abstract: Phase change material holds a good promise as a media of thermal energy storage and intensive heat flux removal. In this context, experiments were conducted to investigate the hydrodynamic and thermodynamic properties of a latent thermal fluid, which consisted of water and well dispersed micro-encapsulated phase change material (MEPCM) particles, flowing in parallel microchannels. It is suggested that MEPCM particles loading induces much higher pressure drop, which is very sensitive to temperature. Compared against water, the heat transfer performance of MEPCM slurry performs much better owing to particles aggregation, collision and micro-convective around the particles. Besides these, latent heat absorbed during phase change process makes the key contribution. It is found that with melting occurrence, Nusselt

Simulation and characterization of a Hanford high-level waste slurry

International Nuclear Information System (INIS)

Russell, R.L.; Smith, H.D.

1996-09-01

The baseline waste used for this simulant is a blend of wastes from tanks 101-AZ, 102-AZ, 106-C, and 102-AY that have been through water washing. However, the simulant used in this study represents a combination of tank waste slurries and should be viewed as an example of the slurries that might be produced by blending waste from various tanks. It does not imply that this is representative of the actual waste that will be delivered to the privatization contractor(s). This blended waste sludge simulant was analyzed for grain size distribution, theological properties both as a function of concentration and aging, and calcining characteristics. The grain size distribution allows a comparison with actual waste with respect to theological properties. Slurries with similar grain size distributions of the same phases are expected to exhibit similar theological properties. Rheological properties may also change because of changes in the slurry's particulate supernate chemistry due to aging. Low temperature calcination allows the potential for hazardous gas generation to be investigated

Manufacturing a submicron structure using a liquid precursor

NARCIS (Netherlands)

Ishihara, R.; Van de Zwan, M.; Trifunovic, M.

2014-01-01

Methods for manufacture of a submicron semiconductor structure on a substrate are described. The method may comprise: forming at least one template layer over a support substrate; forming one or more template structures, preferably one or more recesses and/or mesas, in said template layer, said one

Analysis of high-level radioactive slurries as a method to reduce DWPF turnaround times

International Nuclear Information System (INIS)

Coleman, C.J.; Bibler, N.E.; Ferrara, D.M.; Hay, M.S.

1996-01-01

Analysis of Defense Waste Processing Facility (DWPF) samples as slurries rather than as dried or vitrified samples is an effective way to reduce sample turnaround times. Slurries can be dissolved with a mixture of concentrated acids to yield solutions for elemental analysis by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Slurry analyses can be performed in eight hours, whereas analyses of vitrified samples require up to 40 hours to complete. Analyses of melter feed samples consisting of the DWPF borosilicate frit and either simulated or actual DWPF radioactive sludge were typically within a range of 3--5% of the predicted value based on the relative amounts of sludge and frit added to the slurry. The results indicate that the slurry analysis approach yields analytical accuracy and precision competitive with those obtained from analyses of vitrified samples. Slurry analyses offer a viable alternative to analyses of solid samples as a simple way to reduce analytical turnaround times

In-situ study of the thermal properties of hydrate slurry by high pressure DSC

Energy Technology Data Exchange (ETDEWEB)

Sari, O.; Hu, J.; Brun, F.; Erbeau, N. [Institute of Thermal Engineering, University of Applied Sciences of Western Switzerland, Yverdon-les-Bains (Switzerland); Homsy, P. [Nestec, Vevey (Switzerland); Logel, J.-C. [Axima Refrigeration, Bischheim (France)

2008-07-01

Knowing the enthalpy of hydrate slurry is very essential for energy balance and industrial applications. No direct measurement processes had been developed in this field in the past time. A new experimental method with special device has been developed to carry out on-line measurement of the thermal properties for hydrate slurry under dynamic conditions. With this special device, it is possible to deliver the hydrate slurry to the high pressure DSC (Differential Scanning Calorimetry) directly from the production tank or pipes. Thermal data acquisition will be performed afterwards by DSC. The investigated conditions were at pressure of 30 bar and temperature of {approx}+7 {sup o}C. The dissociation enthalpy of CO{sub 2} hydrate slurry was about 54 kJ/kg, corresponding 10.8% of solid fraction. The on-line measurement results for CO{sub 2} hydrate slurry give a good tendency to apply this phase change slurry to the industrial refrigeration process. (author)

Impact of Nano Particles on Cultural Properties in the Atmosphere of Gyeongju National Park Area Using a Proton Beam

Energy Technology Data Exchange (ETDEWEB)

Kim, K. W.; Do, J. Y.; Park, S. Y.; Kim, T. K.; Ha, J. K. [Gyeongju University, Gyeongju (Korea, Republic of)

2008-04-15

The objective of this research is to investigate the physical and chemical characteristics of atmospheric nanoparticles observed at the National Park area of Gyeongju. The elemental compositions of the submicron aerosols were analyzed using a PIXE (proton induced X-ray emission) method with a 3 MV Tandetron accelerator. In addition, submicron aerosols were prepared for a determination of ions using ion chromatography. Aerosol monitoring was conducted for airborne particles less than 1.0 and 2.5 micron. They were collected on nuclepore filters using PM1.0 and PM2.5 cyclone samplers. The impact of air-mass pathway on the characteristics of particulate matter was analyzed at an end point of Gyeongju with backward trajectory results obtained from the HYSPLIT model. The ratio of submicron aerosol to fine particles in the mass concentration was 40 - 50% in the urban area of Seoul and the national park area of Gyeongju. During the monitoring period, Asian Dust storm events occurred at each monitoring site. The contributions of elements to the submicron aerosols were 8% lower in the urban area than in the national park area. However, the contributions of aged ions to submicron aerosols were relatively higher by 42% in the urban area of Seoul. The elementals of the submicron aerosols were categorized as soil-related, anthropogenic-related, and aerosol-acidity-related species based on an enrichment factor analysis. The average mass fraction of soil-related elements was approximately 20% for Seoul and 75% for Gyeongju. That of the aerosol-acidity-related specie was higher in Seoul and showed a big difference among Asian Dust storm events, non-Asian Dust storm events, and clear atmospheric conditions due to precipitation. Anthropogenic-related elements accounted for 11.7% in Seoul and 5.7% in Gyeongju. S, SO42- and the anthropogenic related elements like Cr, Cd, Pb, which can not be derived from stone materials themselves, were detected both on the stone surface and in

Impact of Nano Particles on Cultural Properties in the Atmosphere of Gyeongju National Park Area Using a Proton Beam

International Nuclear Information System (INIS)

Kim, K. W.; Do, J. Y.; Park, S. Y.; Kim, T. K.; Ha, J. K.

2008-04-01

The objective of this research is to investigate the physical and chemical characteristics of atmospheric nanoparticles observed at the National Park area of Gyeongju. The elemental compositions of the submicron aerosols were analyzed using a PIXE (proton induced X-ray emission) method with a 3 MV Tandetron accelerator. In addition, submicron aerosols were prepared for a determination of ions using ion chromatography. Aerosol monitoring was conducted for airborne particles less than 1.0 and 2.5 micron. They were collected on nuclepore filters using PM1.0 and PM2.5 cyclone samplers. The impact of air-mass pathway on the characteristics of particulate matter was analyzed at an end point of Gyeongju with backward trajectory results obtained from the HYSPLIT model. The ratio of submicron aerosol to fine particles in the mass concentration was 40 - 50% in the urban area of Seoul and the national park area of Gyeongju. During the monitoring period, Asian Dust storm events occurred at each monitoring site. The contributions of elements to the submicron aerosols were 8% lower in the urban area than in the national park area. However, the contributions of aged ions to submicron aerosols were relatively higher by 42% in the urban area of Seoul. The elementals of the submicron aerosols were categorized as soil-related, anthropogenic-related, and aerosol-acidity-related species based on an enrichment factor analysis. The average mass fraction of soil-related elements was approximately 20% for Seoul and 75% for Gyeongju. That of the aerosol-acidity-related specie was higher in Seoul and showed a big difference among Asian Dust storm events, non-Asian Dust storm events, and clear atmospheric conditions due to precipitation. Anthropogenic-related elements accounted for 11.7% in Seoul and 5.7% in Gyeongju. S, SO42- and the anthropogenic related elements like Cr, Cd, Pb, which can not be derived from stone materials themselves, were detected both on the stone surface and in

Hanford Waste Vitrification Plant full-scale feed preparation testing with water and process simulant slurries

International Nuclear Information System (INIS)

Gaskill, J.R.; Larson, D.E.; Abrigo, G.P.

1996-03-01

The Hanford Waste Vitrification Plant was intended to convert selected, pretreated defense high-level waste and transuranic waste from the Hanford Site into a borosilicate glass. A full-scale testing program was conducted with nonradioactive waste simulants to develop information for process and equipment design of the feed-preparation system. The equipment systems tested included the Slurry Receipt and Adjustment Tank, Slurry Mix Evaporator, and Melter-Feed Tank. The areas of data generation included heat transfer (boiling, heating, and cooling), slurry mixing, slurry pumping and transport, slurry sampling, and process chemistry. 13 refs., 129 figs., 68 tabs

Study on the degradation of chitosan slurries

Directory of Open Access Journals (Sweden)

Benjamin Martini

2016-01-01

Full Text Available In the present work, we measured the degradation rate of different chitosan slurries. Several parameters were monitored such as temperature (25 °C, 37 °C, 50 °C; chitosan concentration (1% and 2% (w/V; and polymer molecular weight. The samples were tested in dynamic sweep test mode. This test is able to provide a reliable estimation of viscosity variations of the slurries; in turn, these variations could be related to degradation rate of the system in the considered conditions. The resulting information is particularly important especially in applications in which there is a close relationship between physical properties and molecular structure.

A Fast and Efficient Dehydration Process for Waste Drilling Slurry

Directory of Open Access Journals (Sweden)

Zheng Guo

2017-01-01

Full Text Available In this article, slurry system was converted to colloid from fluid with the colloidization of high polymer coagulants with high viscosity. The solid-liquid separation of the waste slurry was realized by the process of chemical colloidal gel breaking, coagulation function, acidification gelout. In addition, the surface morphology of slurry cake was investigated by using Field emission scanning electron microscope (FE-SEM. The results indicate that mud separation effect is decides on the type of flocculants, gel breaker. The solid content of mud cake increases from 40.5% to 77.5% when A-PA and H20 are employed as the flocculants, gelout, with the dosage of zero point four grams and zero point five grams.

Escherichia coli Contamination of Lettuce Grown in Soils Amended with Animal Slurry

DEFF Research Database (Denmark)

Jensen, Annette Nygaard; Storm, Christina; Forslund, Anita

2013-01-01

A pilot study was conducted to assess the transfer of Escherichia coli from animal slurry fertilizer to lettuce, with E. coli serving as an indicator of fecal contamination and as an indicator for potential bacterial enteric pathogens. Animal slurry was applied as fertilizer to three Danish agric...... types between slurry, soil, and lettuce. The frequent finding of fecal-contaminated lettuce indicates that human pathogens such as Salmonella and Campylobacter can be present and represent food safety hazards.......A pilot study was conducted to assess the transfer of Escherichia coli from animal slurry fertilizer to lettuce, with E. coli serving as an indicator of fecal contamination and as an indicator for potential bacterial enteric pathogens. Animal slurry was applied as fertilizer to three Danish....... coli. A relatively higher frequency of E. coli in lettuce compared with the soil samples at harvest suggests environmental sources of fecal contamination, e.g., wildlife. The higher frequency was supported by the finding of 21 different PFGE types among the E. coli isolates, with only a few common PFGE...

Design of slurry bubble column reactors: novel technique for optimum catalyst size selection contractual origin of the invention

Science.gov (United States)

Gamwo, Isaac K [Murrysville, PA; Gidaspow, Dimitri [Northbrook, IL; Jung, Jonghwun [Naperville, IL

2009-11-17

A method for determining optimum catalyst particle size for a gas-solid, liquid-solid, or gas-liquid-solid fluidized bed reactor such as a slurry bubble column reactor (SBCR) for converting synthesis gas into liquid fuels considers the complete granular temperature balance based on the kinetic theory of granular flow, the effect of a volumetric mass transfer coefficient between the liquid and the gas, and the water gas shift reaction. The granular temperature of the catalyst particles representing the kinetic energy of the catalyst particles is measured and the volumetric mass transfer coefficient between the gas and liquid phases is calculated using the granular temperature. Catalyst particle size is varied from 20 .mu.m to 120 .mu.m and a maximum mass transfer coefficient corresponding to optimum liquid hydrocarbon fuel production is determined. Optimum catalyst particle size for maximum methanol production in a SBCR was determined to be in the range of 60-70 .mu.m.

Radiation hygienization of cattle and swine slurry with high energy electron beam

International Nuclear Information System (INIS)

Skowron, Krzysztof; Olszewska, Halina; Paluszak, Zbigniew; Zimek, Zbigniew; Kałuska, Iwona; Skowron, Karolina Jadwiga

2013-01-01

The research was carried out to assess the efficiency of radiation hygienization of cattle and swine slurry of different density using the high energy electron beam based on the inactivation rate of Salmonella ssp, Escherichia coli, Enterococcus spp and Ascaris suum eggs. The experiment was conducted with use of the linear electron accelerator Elektronika 10/10 in Institute of Nuclear Chemistry and Technology in Warsaw. The inoculated slurry samples underwent hygienization with high energy electron beam of 1, 3, 5, 7 and 10 kGy. Numbers of reisolated bacteria were determined according to the MPN method, using typical microbiological media. Theoretical lethal doses, D 90 doses and hygienization efficiency of high energy electron beam were determined. The theoretical lethal doses for all tested bacteria ranged from 3.63 to 8.84 kGy and for A. suum eggs from 4.07 to 5.83 kGy. Salmonella rods turned out to be the most sensitive and Enterococcus spp were the most resistant to electron beam hygienization. The effectiveness or radiation hygienization was lower in cattle than in swine slurry and in thick than in thin one. Also the species or even the serotype of bacteria determined the dose needed to inactivation of microorganisms. - Highlights: ► The hygienic efficiency of electron beam against slurry was researched. ► The hygienization efficiency depended on the slurry characteristics and microorganism species. ► In most of the cases 7 kGy dose was sufficient for slurry hygienization. ► Dose below 1 kGy allowed for 90% elimination of microorganism population. ► The radiation hygienization is a good alternative for typical slurry treatment methods

Submicron particulate organic matter in the urban atmosphere: a new method for real-time measurement, molecular-level characterization and source apportionment

Science.gov (United States)

Müller, Markus; Eichler, Philipp; D'Anna, Barbara; Tan, Wen; Wisthaler, Armin

2017-04-01

We used a novel chemical analytical method for measuring submicron particulate organic matter in the atmosphere of three European cities (Innsbruck, Lyon, Valencia). Proton-Transfer-Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS) was used in combination with the "chemical analysis of aerosol online" (CHARON) inlet for detecting particulate organic compounds on-line (i.e. without filter pre-collection), in real-time (1-min time resolution), at ng m-3 concentrations, with molecular-level resolution (i.e. obtaining molecular weight and elemental composition information). The CHARON-PTR-ToF-MS system monitored molecular tracers associated with different particle sources including levoglucosan from biomass combustion, PAHs from vehicular traffic, nicotine from cigarette smoking, and monoterpene oxidation products secondarily formed from biogenic emissions. The tracer information was used for interpreting positive matrix factorization (PMF) data which allowed us to apportion the sources of submicron particulate organic matter in the different urban environments. This work was funded through the PIMMS ITN, which was supported by the European Commission's 7th Framework Programme under grant agreement number 287382.

Development of ultra-lightweight slurries with high compressive strength for use in oil wells

Energy Technology Data Exchange (ETDEWEB)

Suzart, J. Walter P. [Halliburton Company, Houston, TX (United States); Farias, A.C. [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil); Ribeiro, Danilo; Fernandes, Thiago; Santos, Reened [Halliburton Energy Services Aberdeen, Scotland (United Kingdom)

2008-07-01

Formations with low fracture gradients or depleted reservoirs often lead to difficult oil well cementing operations. Commonly employed cement slurries (14.0 to 15.8 lb/gal), generate an equivalent circulating density (ECD) higher than the fracture gradient and ultimately lead to formation damage, lost circulation and a decreased top of cement. Given the high price of oil, companies are investing in those and other wells that are difficult to explore. Naturally, lightweight cement slurries are used to reduce the ECD (10.0 to 14.0 lb/gal), using additives to trap water and stabilize the slurry. However, when the density reaches 11.0 lb/gal, the increase in water content may cause a change in characteristics. The focus of this study is extreme cases where it is necessary to employ ultra-lightweight cement slurries (5.5 to 10.0 lb/gal). Foamed slurries have been widely used, and the objective is to set an alternative by developing cement slurries containing uncompressible microspheres, aiming for a density of 7.5 lb/gal as well as high compressive strength. Another benefit in contrast to preparing foamed cement slurries is that there is no requirement for special equipment in the field. Routine laboratory tests such as fluid-loss control, sedimentation, thickening time, free water, compressive strength, and rheology (at room and high temperatures) were performed. Thus, it was concluded that the proposed cement slurries can be used in oil wells. (author)

Semisolid slurry of 7A04 aluminum alloy prepared by electromagnetic stirring and Sc, Zr additions

Directory of Open Access Journals (Sweden)

Jun-wen Zhao

2017-05-01

Full Text Available Slurry preparation is one of the most critical steps for semisolid casting, and its primary goal is to prepare slurry with uniformly distributed fine globules. In this work, electromagnetic stirring (EMS and the addition of Sc and Zr elements were used to prepare semisolid slurry of 7A04 aluminum alloy in a large diameter slurry maker. The effects of different treatments on the microstructure, composition and their radial homogeneity were investigated. The results show that, compared to the slurry without any treatment, large volume slurry with finer and more uniform microstructure can be obtained when treated by EMS, Sc, or Zr additions individually. EMS is more competent in the microstructural and chemical homogenization of the slurry while Sc and Zr additions are more excellent in its microstructural refinement. The combined treatment of EMS, Sc and Zr produces premium 7A04 aluminum alloy slurry with uniformly distributed fine α-Al globules and composition. The interaction mechanism between EMS and Sc and Zr additions was also discussed.

Method for rapid particle size analysis by hydrosizing and nuclear sensing

International Nuclear Information System (INIS)

Daellenbach, C.B.; Mahan, W.M.

1977-01-01

A method and apparatus to practice the method for rapidly determining the size and mass distribution of a sample of randomly sized particles of a known total mass are described. A series of substantially identical hydrocyclones are connected by conduits to each other and to a temperature controlled water feed. By restricting the cross-sectional areas of these conduits to progressively smaller values, the slurry containing the sample particles is caused to increase its velocity as it moves from hydrocyclone to hydrocyclone. As described by the Stokesian theory which relates particle diameter and settling velocity, the largest sized particles are suspended in the closed apex of the first hydrocyclone with smaller sized particles, in given size ranges, being suspended in the next succeeding hydrocyclone's apexes. In this manner, the particles are separated into discrete fractional sizes with a residual slurry of the very smallest particles being discharged. Before the discrete fractions of particles are suspended in their hydrocyclone apexes, a combined photon source, like a gamma ray source, and detector are calibrated with the water temperature kept constant. When the suspension of particles takes place, an attenuation of the radiation from the source is observed at the detector. This attenuation can be related to the mass or weight of the discrete fractions of suspended particles. Electronic circuitry is used to indicate what this fractional mass or weight is as it relates to the total weight of the sample. 6 claims, 4 figs

Slurry sampling high-resolution continuum source electrothermal atomic absorption spectrometry for direct beryllium determination in soil and sediment samples after elimination of SiO interference by least-squares background correction.

Science.gov (United States)

Husáková, Lenka; Urbanová, Iva; Šafránková, Michaela; Šídová, Tereza

2017-12-01

In this work a simple, efficient, and environmentally-friendly method is proposed for determination of Be in soil and sediment samples employing slurry sampling and high-resolution continuum source electrothermal atomic absorption spectrometry (HR-CS-ETAAS). The spectral effects originating from SiO species were identified and successfully corrected by means of a mathematical correction algorithm. Fractional factorial design has been employed to assess the parameters affecting the analytical results and especially to help in the development of the slurry preparation and optimization of measuring conditions. The effects of seven analytical variables including particle size, concentration of glycerol and HNO 3 for stabilization and analyte extraction, respectively, the effect of ultrasonic agitation for slurry homogenization, concentration of chemical modifier, pyrolysis and atomization temperature were investigated by a 2 7-3 replicate (n = 3) design. Using the optimized experimental conditions, the proposed method allowed the determination of Be with a detection limit being 0.016mgkg -1 and characteristic mass 1.3pg. Optimum results were obtained after preparing the slurries by weighing 100mg of a sample with particle size < 54µm and adding 25mL of 20% w/w glycerol. The use of 1μg Rh and 50μg citric acid was found satisfactory for the analyte stabilization. Accurate data were obtained with the use of matrix-free calibration. The accuracy of the method was confirmed by analysis of two certified reference materials (NIST SRM 2702 Inorganics in Marine Sediment and IGI BIL-1 Baikal Bottom Silt) and by comparison of the results obtained for ten real samples by slurry sampling with those determined after microwave-assisted extraction by inductively coupled plasma time of flight mass spectrometry (TOF-ICP-MS). The reported method has a precision better than 7%. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of particle morphology between commercial- and research-grade calcium hydroxide in endodontics.

Science.gov (United States)

Komabayashi, Takashi; Ahn, Chul; Spears, Robert; Zhu, Qiang

2014-09-01

Ca(OH)2 aqueous slurry is widely used as an inter-appointment antimicrobial dressing in root canal treatment. The aim of this study was to quantify the particle size and shape of commercial-grade UltraCal XS (UC) and to compare it with that of research-grade Ca(OH)2 (RG) using a flow particle image analyzer (FPIA). The morphology and penetration inside the dentin tubules of the UC and RG particles were examined using a scanning electron microscope (SEM). UC and RG (10 mg) were mixed with 15 mL of alcohol, and were sonicated. Five milliliters of the dispersion was subjected to FPIA, and particle length, width, perimeter and aspect ratio were analyzed. In addition, UC paste and RG aqueous slurry were agitated on dentin discs and were prepared for SEM examination. There were significant differences between UC and RG with regard to the frequency of different length groups (P < 0.0001). UC contained smaller particles than RG (P < 0.0001). Under SEM, the agitated UC and RG particles occluded the opening of dentin tubules and penetrated inside the dentin tubules. The size of UC particles is smaller than those of RG. Both UC and RG particles were able to penetrate into open dentin tubules.

The stability of a novel weakly alkaline slurry of copper interconnection CMPfor GLSI

Science.gov (United States)

Yao, Caihong; Wang, Chenwei; Niu, Xinhuan; Wang, Yan; Tian, Shengjun; Jiang, Zichao; Liu, Yuling

2018-02-01

Chemical mechanical polishing (CMP) is one of the important machining procedures of multilayered copper interconnection for GLSI, meanwhile polishing slurry is a critical factor for realizing the high polishing performance such as high planarization efficiency, low surface roughness. The effect of slurry components such as abrasive (colloidal silica), complexing agent (glycine), inhibitor (BTA) and oxidizing agent (H2O2) on the stability of the novel weakly alkaline slurry of copper interconnection CMP for GLSI was investigated in this paper. First, the synergistic and competitive relationship of them in a peroxide-based weakly alkaline slurry during the copper CMP process was studied and the stability mechanism was put forward. Then 1 wt% colloidal silica, 2.5 wt% glycine, 200 ppm BTA, 20 mL/L H2O2 had been selected as the appropriate concentration to prepare copper slurry, and using such slurry the copper blanket wafer was polished. From the variations of copper removal rate, root-mean square roughness (Sq) value with the setting time, it indicates that the working-life of the novel weakly alkaline slurry can reach more than 7 days, which satisfies the requirement of microelectronics further development. Project supported by the Major National Science and Technology Special Projects (No. 2016ZX02301003-004-007), the Professional Degree Teaching Case Foundation of Hebei Province, China (No. KCJSZ2017008), the Natural Science Foundation of Hebei Province, China (No. F2015202267), and the Natural Science Foundation of Tianjin, China (No. 16JCYBJC16100).

Evaluation of the transport and resuspension of a simulated nuclear waste slurry: Nuclear Waste Treatment Program

International Nuclear Information System (INIS)

Carleson, T.E.; Drown, D.C.; Hart, R.E.; Peterson, M.E.

1987-09-01

The Department of Chemical Engineering at the University of Idaho conducted research on the transport and resuspension of a simulated high-level nuclear waste slurry. In the United States, the reference process for treating both defense and civilian HLLW is vitrification using the liquid-fed ceramic melter process. The non-Newtonian behavior of the slurry complicates the evaluation of the transport and resuspension characteristics of the slurry. The resuspension of a simulated (nonradioactive) melter feed slurry was evaluated using a slurry designated as WV-205. The simulated slurry was developed for the West Valley Demonstration Project and was used during a pilot-scale ceramic melter (PSCM) experiment conducted at PNL in July 1985 (PSCM-21). This study involved determining the transport characteristics of a fully suspended slurry and the resuspension characteristics of settled solids in a pilot-scale pipe loop. The goal was to predict the transport and resuspension of a full-scale system based on rheological data for a specific slurry. The rheological behavior of the slurry was evaluated using a concentric cylinder rotational viscometer, a capillary tube viscometer, and the pilot-scale pipe loop. The results obtained from the three approaches were compared. 40 refs., 74 figs., 15 tabs

Rheology of sludge-slurry grouts

International Nuclear Information System (INIS)

McDaniel, E.W.

1980-10-01

A series of rheograms was developed that relates the critical velocity (velocity where flow changes from laminar to turbulent) of a cementitious grout that incorporates a suspended sludge-slurry to the critical velocity of a reference grout made with a simulated waste solution. The sludge that is now in the Gunite waste tanks at the Oak Ridge National Laboratory (ORNL) will be suspended and pumped to the new waste storage tanks in Melton Valley. The sludge will then be blended with a cement mix base to form a grout which will be injected underground by the shale fracturing process. This report describes the materials, equipment, and techniques used in the laboratory studies to suspend sludges and mix sludge-slurry grouts that have flow properties similar to those of current shale fracturing grouts. Bentonite clay is an effective suspender in dilute NaNO 3 solutions; 15 wt % solids can be suspended with 2.0 wt % bentonite in a 0.1 M NaNO 3 solution. Other suspending materials were evaluated, but bentonite gave the best results. If a slurry grout becomes too viscous to pump, methods must be available to thin the mixture. A number of thinners, friction reducers, and plasticizers were examined. Q-Broxin, a thinner supplied by Baroid, reduced the velocity of a grout required for turbulent flow in a 5.0-cm (2-in.)-diam tube from 1.76 to 1.20 m/s (5.79 to 3.95 ft/s); FX-32C, a plasticizer supplied by Fox Industries, Inc., reduced the velocity from 1.76 to 0.75 m/s

Leaf absorption of atmospheric ammonia emitted from pig slurry applied beneath the canopy of winter wheat

International Nuclear Information System (INIS)

Gjedde Sommer, S.; Jensen, E.S.; Kofoed Schjoerring, J.

1993-01-01

Absorption of volatilized ammonia after application of slurry onto the soil surface (sand) between rows of a wheat crop was studied in two experiments. The slurry was labelled with 15 N-NH 4 . During seven days the accumulated gaseous N loss from the slurry varied from 6.9 to 11.1 g N m -2 . In April ammonia losses from slurry applied beneath a 5 cm high wheat crop were equal to losses from slurry applied to a fallow, but 2.2% of the lost atmospheric ammonia was taken up by the leaves. In May ammonia loss from slurry applied between the rows of a 43 cm high crop was reduced by 6% compared to the loss from fallow, because of a reduced transfer of ammonia from the slurry to the air. Of the emitted ammonia 3.3% was absorbed by the canopy. (au)

Gas distribution effects on waste properties: Viscosities of bubbly slurries

International Nuclear Information System (INIS)

Gauglitz, P.A.; Shah, R.R.; Davis, R.L.

1994-09-01

The retention and episodic release of flammable gases are critical safety concerns for double-shell tanks that contain waste slurries. The rheological behavior of the waste, particularly of the settled sludge, is critical to characterizing the tendency of the waste to retain gas bubbles. The presence of gas bubbles is expected to affect the rheology of the sludge, but essentially no literature data are available to assess the effect of bubbles. Accordingly, the objectives of this study are to develop models for the effect of gas bubbles on the viscosity of a particulate slurry, develop an experimental method (capillary rheometer), collect data on the viscosity of a bubbly slurry, and develop a theoretical basis for interpreting the experimental data from the capillary rheometer

Development of pixel front-end electronics using advanced deep submicron CMOS technologies

International Nuclear Information System (INIS)

Havranek, Miroslav

2014-09-01

The content of this thesis is oriented on the R and D of microelectronic integrated circuits for processing the signal from particle sensors and partially on the sensors themselves. This work is motivated by ongoing upgrades of the ATLAS Pixel Detector at CERN laboratory and by exploration of new technologies for the future experiments in particle physics. Evolution of technologies for the fabrication of microelectronic circuits follows Moore's laws. Transistors become smaller and electronic chips reach higher complexity. Apart from this, silicon foundries become more open to smaller customers and often provide non-standard process options. Two new directions in pixel technologies are explored in this thesis: design of pixel electronics using ultra deep submicron (65 nm) CMOS technology and Depleted Monolithic Active Pixel Sensors (DMAPS). An independent project concerning the measurement of pixel capacitance with a dedicated measurement chip is a part of this thesis. Pixel capacitance is one of the key parameters for design of the pixel front-end electronics and thus it is closely related to the content of the thesis. The theoretical background, aspects of chip design, performance of chip prototypes and prospect for design of large pixel chips are comprehensively described in five chapters of the thesis.

Development of pixel front-end electronics using advanced deep submicron CMOS technologies