These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Low-rank coal oil agglomeration  

DOEpatents

A low-rank coal oil agglomeration process. High mineral content, a high ash content subbituminous coals are effectively agglomerated with a bridging oil which is partially water soluble and capable of entering the pore structure, and usually coal derived.

Knudson, Curtis L. (Grand Forks, ND); Timpe, Ronald C. (Grand Forks, ND)

1991-01-01

2

Low-rank coal oil agglomeration  

DOEpatents

A low-rank coal oil agglomeration process is described. High mineral content, a high ash content subbituminous coals are effectively agglomerated with a bridging oil which is partially water soluble and capable of entering the pore structure, and is usually coal-derived.

Knudson, C.L.; Timpe, R.C.

1991-07-16

3

Selective oil agglomeration of lignite  

SciTech Connect

In this study, desulfurization and deashing of Adiyaman-Glbai lignite by the agglomeration method were studied. For this purpose, three groups of agglomeration experiments were made. The effects of solid concentration, bridging liquid type and dosage, pH, and screen size on the agglomeration after desliming were investigated in the first group of experiments. The effects of lake water and sea water (the Mediterranean Sea water, the Aegean Sea water, and the Black Sea water) on the agglomeration were investigated in the second group of experiments. The effects of different salts (NaCl, MgCl{sub 2}, and FeCl{sub 3}) on the agglomeration were investigated in the third group of experiments. Agglomeration results showed that the usage of sea waters and soda lake water in the agglomeration medium had a positive effect on the reduction of total sulfur content of agglomerates. In addition, the usage of NaCl, MgCl{sub 2}, and FeCl{sub 3} in the agglomeration medium had a positive effect on the ash content reduction of the agglomerates. 27 refs., 10 figs., 6 tabs.

Halime Abakay Temel; Volkan Bozkurt; Arun Kumar Majumder [Dicle University, Diyarbakir (Turkey). Department of Mining Engineering

2009-01-15

4

Factors affecting the oil agglomeration of Sivas-Divrigi Ulucayir lignite  

SciTech Connect

In the coal industry, the coal particles need to be decreased to a very fine size because of the need of removing inorganic materials from coal. Oil agglomeration is a kind of coal cleaning technique that is used for separation of organic and inorganic parts of fine sized coal. In this study, the oil agglomeration of Sivas-Divrigi (S-D) Ulucayir lignite was carried out by using kerosene, diesel oil, fuel oil, poppy oil, and sunflower oil. The amount of bridging oil was varied from 5% to 25% of the amount of lignite. The effect of oil amount, oil type, solid content, agitation rate and time, pH on agglomeration performance was investigated. Maximum recovery value of 98.18% was observed by using poppy oil. In order to investigate the effect of pH on agglomeration NaOH and HCl is added to the slurry in various amounts. It is decided that the best agglomeration condition is obtained at low pH values. The effect of nonionic surface active agent (Igepal-CA 630) on agglomeration is investigated by adding to the slurry and it is observed that the grade is increased with the amount of surface active agent.

Unal, I.; Gorgun Ersan, M. [Cumhuriyet University, Sivas (Turkey)

2007-07-01

5

Low-rank coal oil agglomeration product and process  

DOEpatents

A selectively-sized, raw, low-rank coal is processed to produce a low ash and relative water-free agglomerate with an enhanced heating value and a hardness sufficient to produce a non-degradable, shippable fuel. The low-rank coal is treated, under high shear conditions, in the first stage to cause ash reduction and subsequent surface modification which is necessary to facilitate agglomerate formation. In the second stage the treated low-rank coal is contacted with bridging and binding oils under low shear conditions to produce agglomerates of selected size. The bridging and binding oils may be coal or petroleum derived. The process incorporates a thermal deoiling step whereby the bridging oil may be completely or partially recovered from the agglomerate; whereas, partial recovery of the bridging oil functions to leave as an agglomerate binder, the heavy constituents of the bridging oil. The recovered oil is suitable for recycling to the agglomeration step or can serve as a value-added product.

Knudson, C.L.; Timpe, R.C.; Potas, T.A.; DeWall, R.A.; Musich, M.A.

1992-11-10

6

Low-rank coal oil agglomeration product and process  

SciTech Connect

A selectively-sized, raw, low-rank coal is processed to produce a low ash and relative water-free agglomerate with an enhanced heating value and a hardness sufficient to produce a non-decrepitating, shippable fuel. The low-rank coal is treated, under high shear conditions, in the first stage to cause ash reduction and subsequent surface modification which is necessary to facilitate agglomerate formation. In the second stage the treated low-rank coal is contacted with bridging and binding oils under low shear conditions to produce agglomerates of selected size. The bridging and binding oils may be coal or petroleum derived. The process incorporates a thermal deoiling step whereby the bridging oil may be completely or partially recovered from the agglomerate; whereas, partial recovery of the bridging oil functions to leave as an agglomerate binder, the heavy constituents of the bridging oil. The recovered oil is suitable for recycling to the agglomeration step or can serve as a value-added product.

Knudson, Curtis L. (Grand Forks, ND); Timpe, Ronald C. (Grand Forks, ND); Potas, Todd A. (Plymouth, MN); DeWall, Raymond A. (Grand Forks, ND); Musich, Mark A. (Grand Forks, ND)

1992-01-01

7

Preliminary characterization of a gas-promoted oil agglomeration process  

SciTech Connect

The agglomeration of aqueous suspensions of Pittsburgh No. 8 coal particles with i-octane was studied by employing a scale model mixing system which measured both agitator speed and torque. The progress of agglomeration was monitored by observing changes in agitator torque and was confirmed by examining samples of the suspension with an optical microscope. When a suspension containing 30 w/w% solids was degassed and then conditioned with 20 v/w% i-octane (20 ml i-octane/100 g coal), no agglomeration took place until a small amount of air (e.g., 9 v/w%) was introduced. Subsequent changes in agitator torque indicated that the ensuing process of agglomeration was complex and consisted of several stages involving various interactions between coal particles, oil drops, and gas bubbles. The time required to produce spherical agglomerates was determined for different experimental conditions by conducting a number of agglomeration tests involving different mixing tank sizes and different impeller sizes and speeds. The results indicate that agglomeration time decreases with increasing power input per unit volume and increasing gas concentration.

Drzymala, J.; Wheelock, T.D. [Iowa State Univ., Ames, IA (United States)

1996-12-31

8

Basic principles and mechanisms of selective oil agglomeration  

SciTech Connect

The overall objective is to determine the basic principles and mechanisms which underlie a number of selective oil agglomeration processes that have been proposed for beneficiating fine-size coal. An understanding of the basic principles and mechanisms will greatly facilitate technical development and application of such processes to various types of coal. 5 refs., 16 figs., 2 tabs.

Wheelock, T.D.; Drzymala, J.; Allen, R.W.; Hu, Y.C.; Tyson, D.; Ziaoping, Qiu, Lessa, A.

1990-04-01

9

Basic principles and mechanisms of selective oil agglomeration  

SciTech Connect

The overall objective of this work is to determine the important principles and basic mechanisms which underlie various selective oil agglomeration processes for beneficiating fine-size coal in order to facilitate the technical development and application of such processes to various types of coal. The recent work described herein has involved a more detailed study of the effects of mild oxidation on the surface properties of different types of coal and the relationship between the agglomerability of oxidized coals and their surface properties. In addition, the work has involved developing more effective means for separating coal and pyrite by finding and applying selective depressants for pyrite.

Wheelock, T.D.

1994-07-01

10

Basic principles and mechanisms of selective oil agglomeration  

SciTech Connect

Numerous measurements of the heat of immersion of coal were conducting using several different particle size fractions of No. 2 Gas Seam coal from Raleigh County, West Virginia. The heat of immersion was determined in water, methanol, heptane, hexadecane and neohexane (2,2-dimethybutane). A comparison of the results with those determined previously for Illinois No. 6 coal is discussed. A number of potential pyrite depressants for use in oil agglomeration of coal were screened by testing the response of sulfidized mineral pyrite to agglomeration with heptane in the presence of the potential depressant. The following were tested; sodium dithionite, sodium thiosulfate, ferrous sulfate, ferric sulfate, titanous chloride, hydrogen peroxide, Oxone (a form of potassium monopersulfate), pyrogallol, quebracho (colloidal dispersant derived from tree bark), milk whey, and several organic thiols. Ferric chloride was applied to mixtures of Upper Freeport coal and sulfidized mineral pyrite before subjecting the mixtures to agglomeration with heptane. 7 refs., 23 figs., 3 tabs.

Wheelock, T.D.; Drzymala, J.; Allen, R.W.; Hu, Y.-C.; Tyson, D.; Xiaoping, Qiu; Lessa, A.

1990-01-01

11

Development of a gas-promoted oil agglomeration process: Air-promoted oil agglomeration of moderately hydrophobic coals. 2: Effect of air dosage in a model mixing system  

SciTech Connect

In a selective oil agglomeration process for cleaning coal, fine-size particles are suspended in water and treated with a water-immiscible hydrocarbon which can range from pentane to heavy fuel oil. Vigorous agitation is applied to disperse the oil and to produce frequent contacts between oil-coated particles. In Part 1 of this series of papers, it was shown that a definite amount of air had to be present in a laboratory mixing unit which produced a moderate shear rate in order to form compact, spherical agglomerates in an aqueous suspension of moderately hydrophobic coal using heptane or hexadecane as an agglomerate. In this paper, the effects of different amounts of air including dissolved air are discussed. The results indicate that a small amount of air will trigger the process of agglomeration, and even the air dissolved in water under equilibrium conditions at room temperature and pressure is sufficient to promote agglomeration provided it is released from solution.

Drzymala, J.; Wheelock, T.D.

1996-07-01

12

TEM and HRTEM of Soot-in-oil particles and agglomerates from internal combustion engines  

NASA Astrophysics Data System (ADS)

Over time, the performance of lubricating oil in a diesel engine is affected by the build-up of carbon soot produced by the combustion process. TEM and HRTEM are commonly used to investigate the characteristics of individual and agglomerated particles from diesel exhaust, to understand the structure and distribution of the carbon sheets in the primary particles and the nanostructure morphology. However, high resolution imaging of soot-in-oil is more challenging, as mineral oil is a contaminant for the electron microscope and leads to instability under the electron beam. In this work we compare solvent extraction and centrifugation techniques for removing the mineral oil contaminant, and the effect on particle size distribution.

Fay, M. W.; La Rocca, A.; Shayler, P. J.

2014-06-01

13

Desulfurization and deashing of Hazro coal by selective oil agglomeration in various water mediums  

SciTech Connect

The aim of this study was to study the effects of various water mediums on desulfurization and deashing of Hazro coal by the agglomeration method. For this purpose, three groups of agglomeration experiments were made. The effects of some parameters that markedly influence the effectiveness of selective oil agglomeration, such as solid concentration, bridging liquid concentration, and pH, on the agglomeration were investigated in the first group of experiments. The effects of different salts (NaCl, MgCl{sub 2}, and FeCl{sub 3}) on the agglomeration were investigated in the second group of experiments. The effects of lake water and sea water on the agglomeration were investigated in the third group of experiments. The influences of the Mediterranean Sea water and Aegean Sea water on the removal of ash and total sulfur were found to be important. 22 refs., 7 figs., 6 tabs.

Halime Abakay Temel; Fatma Deniz Ayhan [Dicle University, Diyarbakir (Turkey). Department of Mining Engineering

2006-10-15

14

ECONOMIC EVALUATION OF OIL AGGLOMERATION FOR RECOVERY OF FINE COAL REFUSE  

EPA Science Inventory

The report gives results of an evaluation of the economics of an oil-agglomeration process (with and without an oil recovery system) for recovering coal fines from a fine refuse stream of 105 ton/hr from a coal preparation plant. The two base case processes studied are oil-agglom...

15

Coal oxidation and its effect on oil agglomeration  

SciTech Connect

Small particles of high volatile bituminous coal from two different sources were oxidized by air at 150 C for up to 72 hrs. As the treatment progressed, samples of coal were recovered and characterized by measuring the heat of immersion of the particles in water and determining the agglomerability of the material with heptane while suspended in water. As oxidation proceeded, the heat of immersion increased and the agglomerability decreased, and a direct relationship between the two was observed.

Qiu, X.; Wheelock, T.D. [Ames Lab., IA (United States); [Iowa State Univ. of Science and Technology, Ames, IA (United States)

1991-12-31

16

New surfactant for hydrate anti-agglomeration in hydrocarbon flowlines and seabed oil capture.  

PubMed

Anti-agglomeration is a promising solution for gas hydrate risks in deepsea hydrocarbon flowlines and oil leak captures. Currently ineffectiveness at high water to oil ratios limits such applications. We present experimental results of a new surfactant in rocking cell tests, which show high efficiency at a full range of water to oil ratios; there is no need for presence of the oil phase. We find that our surfactant at a very low concentration (0.2 wt.% of water) keeps the hydrate particles in anti-agglomeration state. We propose a mechanism different from the established water-in-oil emulsion theory in the literature that the process is effective without the oil phase. There is no need to emulsify the water phase in the oil phase for hydrate anti-agglomeration; with oil-in-water emulsion and without emulsion hydrate anti-agglomeration is presented in our research. We expect our work to pave the way for broad applications in offshore natural gas production and seabed oil capture with very small quantities of an eco-friendly surfactant. PMID:23660023

Sun, Minwei; Firoozabadi, Abbas

2013-07-15

17

Remediation of oil-contaminated sand by coal agglomeration using ball milling.  

PubMed

The mechanical shear force provided by a less energy intensive device (usually operating at 20-200 rpm), a ball mill, was used toperform coal agglomeration and its effects on remediation of a model fuel oil-contaminated sand were evaluated. Important process parameters such as the amount of coal added, milling time, milling speed and the size of milling elements are discussed. The results suggested that highly hydrophobic oil-coal agglomerates, formed by adding suitable amounts of coal into the oil-contaminated sand, could be mechanically liberated from cleaned sand during ball milling and recovered as a surface coating on the steel balls. Over 90% removal of oil from oil-contaminated sand was achieved with 6 wt% of coal addition and an optimum ball milling time of 20 min and speed of 200 rpm. This novel process has considerable potential for cleaning oil-contaminated sands. PMID:22329146

Shin, Yu-Jen; Shen, Yun-Hwei

2011-10-01

18

APPLICATION OF OIL AGGLOMERATION FOR EFFLUENT CONTROL FROM COAL CLEANING PLANTS  

EPA Science Inventory

The report discusses the potential applicability of oil agglomeration for the control of black water effluents from coal cleaning plants processing four different coals. Removal and recovery of the coal from each of the black waters produced aqueous suspensions of mineral matter ...

19

Mechanisms for selective agglomeration of coals  

SciTech Connect

Work continued on the basic mechanisms which underlie various processes for beneficiating aqueous suspensions of coal by selective agglomeration with oil. A new method was demonstrated for characterizing the agglomerability of coal suspensions. This method utilizes a photometric dispersion analyzer to monitor changes in the turbidity of a particle suspension as increasing amounts of oil are added to the suspension in a batch agglomeration test. Agglomeration of the particles leads to a marked decrease in the turbidity of the suspension. Another experimental technique was also demonstrated for characterizing oil agglomeration. This technique involves measuring the rate of growth of agglomerates in a continuous flow system operating under stead-state conditions. The data are analyzed by means of a population balance. The results of a preliminary set of experiments in which Indiana V seam coal was agglomerated with tetralin seemed to fit a particular growth model very well. Equipment was also constructed for studying the kinetics of agglomeration in a batch process. While earlier work showed that quebracho (a commercially available dispersant) is a strong agglomeration depressant for pyrite, recent experiments with mixtures of Upper Freeport coal and mineral pyrite showed that quebracho does not appear to be sufficiently selective. Further consideration was given to the separation of mixtures of coal and pyrite agglomeration with heptane. 2 refs., 17 figs., 1 tab.

Wheelock, T.D.; Drzymala, J.; Allen, R.W.; Hu, Y.-C.; Tyson, D.; Xiaoping, Qiu; Lessa, A.

1989-05-01

20

Preparation of agglomerated crystals of lactose for direct tabletting by the spherical crystallization technique  

Microsoft Academic Search

Objectives: Lactose is widely used as a filler or diluent in tablets and capsules and direct compresion grade of lactose can be used to carry small quantities of drug and this permits tablet to be made without granulation. The aim of the present study was to produce lactose agglomerates with high flowability and compactibility using crystallization technique. Methods: The spherical

21

Preparation of Agglomerated Crystals for Direct Tabletting and Microencapsulation by the Spherical Crystallization Technique with a Continuous System  

Microsoft Academic Search

Adhesive and cohesive properties of chlorpromazine hydrochloride (CP) crystals were modified to improve their powder processing, e.g., direct tabletting and microencapsulation, by agglomeration. Moreover, sustained-released gelling microcapsules of CP were devised to prolong the pharmacological effect. The spherical crystallization technique was applied to prepare agglomerates for direct tabletting and microencapsulation to use them as core materials. The ethanolic solution dissolving

Toshiyuki Niwa; Hirofumi Takeuchi; Tomoaki Hino; Akira Itoh; Yoshiaki Kawashima; Katsumi Kiuchi

1994-01-01

22

Basic principles and mechanisms of selective oil agglomeration. Fossil energy interim report, October 1, 1983--September 30, 1992  

SciTech Connect

Numerous agglomeration tests were conducted with several types of low-ash coal and graphite, high grade mineral pyrite, and other materials. Relatively pure hydrocarbons, including heptane and hexadecane, were used as agglomerants. Access of air to the system was controlled. Particle recovery by agglomeration was observed to depend on a number of system parameters. Among the most important parameters are the hydrophobicity of the particles and the oil dosage, so that the, recovery of solids per unit of oil administered is proportional to the hydrophobicity. The pH and ionic strength of the aqueous suspension affect particle recovery in different ways depending on the surface properties of the particles. On the other hand, the presence of air in the system generally improves particle recovery. The greatest effect of air was observed in a closely related study which showed that air had to be present to produce good agglomerates from a moderately hydrophobic coal in a mixer producing a lower shear rate. The rate of agglomeration was found to be much greater for a strongly hydrophobic coal than for a moderately hydrophobic coal, and the rate was observed to be proportional to the oil dosage. Also the rate was enhanced by the presence of air in the, system. For hydrophobic coals, the rate increased with increasing ionic strength of the aqueous medium, but it was not affected greatly by pH over a wide range. The separation of coal and pyrite particles by selective agglomeration was found to depend on the relative hydrophobicity of the materials, the oil dosage, and the properties of the aqueous medium.

Wheelock, T.D.

1992-12-31

23

The use of starch to enhance sulfur and ash removal from coal by selective oil agglomeration  

SciTech Connect

We have found that the use of starch or gelatin, as an additive in the Otisca T-Process of selective oil agglomeration of coal, leads to a considerable improvement in the reduction of pyritic sulfur and of ash-forming minerals. A patent application has been filed; (Good Badgugar). Improvement in rejection of pyritic sulfur by up to 55% has been found, and improvement in ash rejection by up to 28%. Carbon recovery of 97.5 to 99.1% was obtained when the starch concentration was in the range, 30 to 200 ppM in the water. Three different bituminous coals were used: Upper Freeport, Kentucky No. 9, and Illinois No. 6.

Good, R.J.; Badgujar, M.N.

1990-01-01

24

Diffusion mediated agglomeration of CdS nanoparticles via Langmuir–Blodgett technique  

SciTech Connect

Graphical abstract: - Highlights: • Diffusion mediated agglomeration of CdS nanoparticles are discussed. • Formation of CdS nanoparticles are confirmed by the change of chain length in XRD. • AFM shows the agglomeration of particles with a film swelling of about 5 ?. • UV–vis absorbance suggests that the grown particles show quantum confinement. • Hexagonal form of particle was confirmed by UV–vis reflectivity. - Abstract: We have reported a diffusion mediated agglomeration of cadmium sulphide (CdS) nanoparticles within cadmium arachidate (CdA{sub 2}) film matrix. The structural morphology and formation of CdS nanoparticles are characterized by X-ray diffraction (XRD), X-ray reflectivity (XRR), atomic force microscopy (AFM) and ultraviolet-visible spectroscopy techniques. X-ray diffraction (XRD) results show a change in bilayer difference from 53.04 ? to 43 ? after the sulphidation. An epitaxial growth of the films by ?5 ? after sulphidation is confirmed from atomic force microscopy studies. The particle size calculated form UV–vis absorption edges are found to be varying from 2.6 nm to 3.3 nm for the different layers. A lateral dimension of 72–80 nm from AFM measurements and a size of 2.6–3.3 nm have confirmed one side flat pseudo two-dimensional disk-like nanoparticles. UV–vis reflectivity peak at E{sub 1} (A) confirms the formation of hexagonal CdS nanoparticles along the c-axis.

Das, Nayan Mani, E-mail: nayanmanidas3@gmail.com; Roy, Dhrubojyoti; Gupta, P.S.

2013-10-15

25

Preparation of Spherical Crystal Agglomerates of Naproxen Containing Disintegrant for Direct Tablet Making by Spherical Crystallization Technique  

Microsoft Academic Search

The purpose of this research was to obtain directly compressible agglomerates of naproxen containing disintegrant by spherical\\u000a crystallization technique. Acetone–water containing hydroxypropyl celloluse (HPC) and disintegrant was used as the crystallization\\u000a system. In this study croscarmellose sodium (Ac–Di–Sol) was employed as disintegrant. The agglomerates were characterized\\u000a by differential scanning calorimetry (DSC), powder X-ray diffraction (XRPD), and scanning electron microscopy and

A. Nokhodchi; M. Maghsoodi

2008-01-01

26

Improved Static Compression Behaviors and Tablettabilities of Spherically Agglomerated Crystals Produced by the Spherical Crystallization Technique with a Two-Solvent System  

Microsoft Academic Search

Purpose. Poorly compressible crystals of acebutolol hydrochloride were agglomerated by the spherical crystallization technique with a two-solvent system to improve the compressibility for direct tabletting. The mechanism of improvements in static compression behaviors and tablettabilities of the spherically agglomerated crystals were investigated.

Yoshiaki Kawashima; Fude Cui; Hirofumi Takeuchi; Toshiyuki Niwa; Tomoaki Hino; Katsumi Kiuchi

1995-01-01

27

Solvent recovery for the oil-agglomeration coal-cleaning process. Final report  

SciTech Connect

Solvent removal and recovery from coal pellets produced by the spherical agglomeration process were studied. Different types of pellets were prepared using an eastern and a western coal and three grades of solvents. Three dryers, namely Turbo, Roto-louvre, and Holo-flite, were selected for laboratory testing to remove the solvent from the pellets. Results showed that all three dryers can evaporate the solvent from the coal pellets to very low levels; however, a large amount of coal fines was generated in the Holo-flite dryer. Superheated steam and simulated flue gas were tested as the drying media to study the drying and recovery of the solvent from the coal pellets. Solvent recovery was found to be very high when superheated steam was used but very poor when simulated flue gas was used. It is recommended that the Turbo dryer, which has been using superheated steam in some of its commercial units, be studied further on a pilot scale. A flow scheme of the pilot plant is proposed.

Cheh, C.H.

1981-09-01

28

Development of clean coal and clean soil technologies using advanced agglomeration techniques  

SciTech Connect

Three major topics are discussed in this report: (1) Upgrading of Low Rank Coals by the Agflotherm Process. Test data, procedures, equipment, etc., are described for co-upgrading of subbituminous coals and heavy oil; (2) Upgrading of Bituminous Coals by the Agflotherm Process. Experimental procedures and data, bench and pilot scale equipments, etc., for beneficiating bituminous coals are described; (3) Soil Clean-up and Hydrocarbon Waste Treatment Process. Batch and pilot plant tests are described for soil contaminated by tar refuse from manufactured gas plant sites. (VC)

Ignasiak, B.; Ignasiak, T.; Szymocha, K.

1990-01-01

29

Mathematical programming techniques for crude oil scheduling  

Microsoft Academic Search

We consider the application of formal, mathematical programming techniques to the problem of scheduling the crude oil supply to a refinery. The relevant key decisions include the the allocation of crude oils to refinery and portside tanks, the connection of refinery tanks to crude distillation units (CDUs), the sequence and amounts of crudes pumped from the ports to the refineries,

N. Shah

1996-01-01

30

Ultrasonic techniques in oil well logging  

SciTech Connect

Oil well logging is used to provide the oil and gas industry with information essential to discovering and extracting hydrocarbons. This paper addresses two ultrasonic measurements that are presently used in oil well logging. The most widely used is an ultrasonic technique that evaluates the integrity of the cement seal after a steel casing has been lowered and cemented in place. This instrument is also capable of monitoring the effects of corrosion both on the inner and outer surfaces of the casing. The measurement is based on a pulsed resonant technique. Less widely used is the Borehole Televiewer, an ultrasonic scanning device based on a pulse-echo technique. It provides an acoustic image of geologic features such as rock layers and fractures.

Havira, R.M.

1988-01-01

31

The use of starch to enhance sulfur and ash removal from coal by selective oil agglomeration. Quarterly technical progress report No. 12, July 1--September 30, 1990  

SciTech Connect

We have found that the use of starch or gelatin, as an additive in the Otisca T-Process of selective oil agglomeration of coal, leads to a considerable improvement in the reduction of pyritic sulfur and of ash-forming minerals. A patent application has been filed; (Good & Badgugar). Improvement in rejection of pyritic sulfur by up to 55% has been found, and improvement in ash rejection by up to 28%. Carbon recovery of 97.5 to 99.1% was obtained when the starch concentration was in the range, 30 to 200 ppM in the water. Three different bituminous coals were used: Upper Freeport, Kentucky No. 9, and Illinois No. 6.

Good, R.J.; Badgujar, M.N.

1990-12-31

32

Fuel agglomerates and method of agglomeration  

DOEpatents

Solid fuel agglomerates are prepared of particulate coal or other carbonaceous material with a binder having a high humic acid or humate salt content. The humic acid is extracted from oxidized carbonaceous material with a mild aqueous alkali solution of, for instance, ammonia. The particulate material is blended with the extract which serves as the binder for the agglomerates. The water-resistant agglomerates are formed such as by pelletizing, followed by drying to remove moisture and solidify the humic acid binder throughout the agglomerate.

Wen, Wu-Wey (Murrysville, PA)

1986-01-01

33

Authentication of vegetable oils by chromatographic techniques.  

PubMed

Food authentication has been evolving continually to situations that were basically governed by a global market trend. Analytical techniques have been developed or modified to give plausible solutions to the devious adulterations at each moment. Classical tests have largely been replaced with newer technical procedures, most of which are based on gas chromatography, with some being based on high-performance liquid chromatography. Determination of trans-fatty acid and sterolic composition, together with sterol-dehydration products, have been used most frequently used to detect contamination and adulteration. Sophisticated new adulterations, e.g., olive oil with hazelnut oil, represent a new challenge for the next millennium, although suggestive proposals for detecting these kinds of adulterations are emerging with the contribution of databases and mathematical algorithms. PMID:10905696

Aparicio, R; Aparicio-Ruíz, R

2000-06-01

34

Multidimensional nature of fluidized nanoparticle agglomerates.  

PubMed

We show that fluidized nanoparticle agglomerates are hierarchical fractal structures with three fractal dimensions: one characterizing sintered aggregates formed during nanoparticle synthesis, one that is also found in stored agglomerates and represents unbroken agglomerates, and one describing the large agglomerates broken during fluidization. This has been possible by using spin-echo small-angle neutron scattering-a relatively novel technique that, for the first time, allowed to characterize in situ the structure of fluidized nanoparticle agglomerates from 21 nm to ?20 ?m. The results show that serial agglomeration mechanisms in the gas phase can generate nanoparticle clusters with different fractal dimensions, contradicting the common approach that considers fluidized nanoparticle agglomerates as single fractals, in analogy to the agglomerates formed by micron-sized particles. This work has important implications for the fluidization field but also has a wider impact. Current studies deal with the formation and properties of clusters where the building blocks are particles and the structure can be characterized by only one fractal dimension. However, fluidized nanoparticle agglomerates are low-dimensional clusters formed by higher-dimensional clusters that are formed by low-dimensional clusters. This multifractality demands a new type of multiscale model able to capture the interplay between different scales. PMID:25313446

de Martín, Lilian; Bouwman, Wim G; van Ommen, J Ruud

2014-10-28

35

Separating oil from oil-water emulsions by electroflotation technique  

Microsoft Academic Search

The separation of finely dispersed oil from oil-water emulsions was carried out in an electroflotation cell which has a set of electrodes, a lead anode and stainless steel screen cathode. The effect of operating parameters on the performance of the batch cell was examined. The parameters investigated are electrical current, oil concentration, flotation time and flocculant agent concentrations. A well-fitted

Ashraf Y. Hosny

1996-01-01

36

Slugging technique saves oil mud costs  

Microsoft Academic Search

While drillers gain feet per hour by relaxing fluid loss requirements in oil base mud systems, the results often are costly. For example, a $100 per barrel oil mud that loses four barrels per hour to the formation leaves an operator with a $9,600 daily replenishment charge. A method has been devised to seal the well to minimize fluid seepage

T. Brookey; L. Edwards; J. Cowan

1982-01-01

37

Scattering matrix elements of fractal-like soot agglomerates  

SciTech Connect

The possibility of measuring scattering-matrix (Mueller matrix) elements of soot agglomerates with laser diagnostic techniques is explored. To show this, we calculated the scattering-matrix elements of arbitrary-shaped soot agglomerates. The sensitivity of scattering-matrix elements to optical and morphological characteristics of fractal-like soot agglomerates is discussed. Finally, possible measurement techniques are suggested to identify soot structures from scattering-matrix elements. {copyright} 1997 Optical Society of America

Manickavasagam, S.; Menguec, M.P. [Department of Mechanical Engineering, University of Kentucky, Lexington, Kentucky 40506 (United States)

1997-02-01

38

Agglomeration of Dust  

SciTech Connect

The agglomeration of the matter in plasma, from the atomic level up to millimetre size particles, is here considered. In general we identify a continuous growth, due to deposition, and two agglomeration steps, the first at the level of tens of nanometres and the second above the micron. The agglomeration of nano-particles is attributed to electrostatic forces in presence of charge polarity fluctuations. Here we present a model based on discrete currents. With increasing grain size the positive charge permanence decreases, tending to zero. This effect is only important in the range of nanometre for dust of highly dispersed size. When the inter-particle distance is of the order of the screening length another agglomeration mechanism dominates. It is based on attractive forces, shadow forces or dipole-dipole interaction, overcoming the electrostatic repulsion. In bright plasma radiation pressure also plays a role.

Annaratone, B. M.; Arnas, C.; Elskens, Y. [Laboratoire de Physique des Interactions Ioniques et Moleculaires, CNRS/Universite de Provence, case 321, 13397, Marseille (France); Antonova, T.; Morfill, G. [Max-Planck Institute fuer Extraterrestrische Physik Postfach 1312 D-85741 Garching (Germany)

2008-09-07

39

New technique for oil backstreaming contamination measurements  

NASA Technical Reports Server (NTRS)

Due to the large size and the number of diffusion pumps, space simulation chambers cannot be easily calibrated by the usual test dome method for measuring backstreaming from oil diffusion pumps. In addition, location dependent contamination may be an important parameter of the test. The backstreaming contamination in the Space Power Facility (SPF) near Sandusky, Ohio, the largest space simulation vacuum test chamber in the U.S.A. was measured. Small size clean silicon wafers as contamination sensors placed at all desired measurement sites were used. The facility used diffusion pumps with DC 705 oil. The thickness of the contamination oil film was measured using ellipsometry. Since the oil did not wet uniformly the silicon substrate, two analysis models were developed to measure the oil film: continuous, homogeneous film and islands of oil with the islands varying in coverage fraction and height. In both cases, the contamination film refractive index was assumed to be that of DC 705. The second model improved the ellipsometric analysis quality parameter by up to two orders of magnitude, especially for the low coverage cases. Comparison of the two models for our case shows that the continuous film model overestimates the oil volume by less than 50 percent. Absolute numbers for backstreaming are in good agreement with published results for diffusion pumps. Good agreement was also found between the ellipsometric results and measurements done by x ray photoelectron spectroscopy (XPS) and by scanning electron microscopy (SEM) on samples exposed to the same vacuum runs.

Alterovitz, S. A.; Speier, H. J.; Sieg, R. M.; Drotos, M. N.; Dunning, J. E.

1993-01-01

40

Development and Application of Agglomerated Multigrid Methods for Complex Geometries  

NASA Technical Reports Server (NTRS)

We report progress in the development of agglomerated multigrid techniques for fully un- structured grids in three dimensions, building upon two previous studies focused on efficiently solving a model diffusion equation. We demonstrate a robust fully-coarsened agglomerated multigrid technique for 3D complex geometries, incorporating the following key developments: consistent and stable coarse-grid discretizations, a hierarchical agglomeration scheme, and line-agglomeration/relaxation using prismatic-cell discretizations in the highly-stretched grid regions. A signi cant speed-up in computer time is demonstrated for a model diffusion problem, the Euler equations, and the Reynolds-averaged Navier-Stokes equations for 3D realistic complex geometries.

Nishikawa, Hiroaki; Diskin, Boris; Thomas, James L.

2010-01-01

41

Thermal Effusivity of Vegetable Oils Obtained by a Photothermal Technique  

NASA Astrophysics Data System (ADS)

Thermal properties of several vegetable oils such as soy, corn, and avocado commercial oils were obtained by using a photopyroelectric technique. The inverse photopyroelectric configuration was used in order to obtain the thermal effusivity of the oil samples. The theoretical equation for the photopyroelectric signal in this configuration, as a function of the incident light modulation frequency, was fitted to the experimental data in order to obtain the thermal effusivity of these samples. The obtained results are in good agreement with the thermal effusivity reported for other vegetable oils. All measurements were done at room temperature.

Cervantes-Espinosa, L. M.; de L. Castillo-Alvarado, F.; Lara-Hernández, G.; Cruz-Orea, A.; Hernández-Aguilar, C.; Domínguez-Pacheco, A.

2014-10-01

42

Agglomeration of magnetic nanoparticles.  

PubMed

The formation of agglomerates by salt-induced double layer compression of magnetic nanoparticles in the absence and presence of an external magnetic field was investigated experimentally as well as computationally in this study. The structures of the agglomerates were analyzed through scanning electron microscopy and proved to be highly porous and composed of large spaces among the branches of a convoluted network. In the absence of an external magnetic field, the branches of such a network were observed to be oriented in no particular direction. In contrast, when the agglomeration process was allowed to occur in the presence of an external magnetic field, these branches appeared to be oriented predominantly in one direction. A modified Discrete Element Method was applied to simulate the agglomeration process of magnetic nanoparticles both in the absence and presence of an external magnetic field. The simulations show that agglomeration occurred by the formation of random clusters of nanoparticles which then joined to form a network. In the presence of anisotropic magnetic forces, these clusters were rotated to align along the direction of the magnetic field and the final network formed consisted largely of elongated branches of magnetic nanoparticles. PMID:22462837

Lim, Eldin Wee Chuan; Feng, Ruili

2012-03-28

43

Improved flowability and compactibility of spherically agglomerated crystals of ascorbic acid for direct tableting designed by spherical crystallization process  

Microsoft Academic Search

Spherically agglomerated crystals of ascorbic acid with improved compactibility for direct tableting were successfully engineered by the spherical crystallization technique. In this process, ascorbic acid crystals were precipitated by a solvent change method, followed by their agglomerations with the emulsion solvent diffusion (ESD) or spherical agglomeration (SA) mechanism. The micromeritic properties, such as flowability and packability of the spherically agglomerated

Y Kawashima; M Imai; H Takeuchi; H Yamamoto; K Kamiya; T Hino

2003-01-01

44

Proper Oil Sampling Intervals and Sample Collection Techniques Gasoline/Diesel/Natural Gas Engines  

E-print Network

Proper Oil Sampling Intervals and Sample Collection Techniques Gasoline/Diesel/Natural Gas Engines: · Oil samples can be collected during oil changes. Follow manufacturers recommendations on frequency (hours, mileage, etc) of oil changes. · Capture a sample from the draining oil while the oil is still hot

45

In vitro dosimetry of agglomerates  

NASA Astrophysics Data System (ADS)

Agglomeration of nanoparticles in biological fluids is a pervasive phenomenon that leads to difficulty in the interpretation of results from in vitro exposure, primarily due to differing particokinetics of agglomerates to nanoparticles. Therefore, well-defined small agglomerates were designed that possessed different particokinetic profiles, and their cellular uptake was compared to a computational model of dosimetry. The approach used here paves the way for a better understanding of the impact of agglomeration on the nanoparticle-cell interaction.Agglomeration of nanoparticles in biological fluids is a pervasive phenomenon that leads to difficulty in the interpretation of results from in vitro exposure, primarily due to differing particokinetics of agglomerates to nanoparticles. Therefore, well-defined small agglomerates were designed that possessed different particokinetic profiles, and their cellular uptake was compared to a computational model of dosimetry. The approach used here paves the way for a better understanding of the impact of agglomeration on the nanoparticle-cell interaction. Electronic supplementary information (ESI) available: ITC data for tiopronin/Au-NP interactions, agglomeration kinetics at different pHs for tiopronin-coated Au-NPs, UV-Vis spectra in water, PBS and DMEM and temporal correlation functions for single Au-NPs and corresponding agglomerates, calculation of diffusion and sedimentation parameters, modelling of relative cell uptake based on the ISDD model and cytotoxicity of single Au-NPs and their agglomerates, and synthesis and cell uptake of large spherical Au-NPs. See DOI: 10.1039/c4nr00460d

Hirsch, V.; Kinnear, C.; Rodriguez-Lorenzo, L.; Monnier, C. A.; Rothen-Rutishauser, B.; Balog, S.; Petri-Fink, A.

2014-06-01

46

Measurement of Thin Oil Film Thickness Using Ultrasonic Technique  

NASA Astrophysics Data System (ADS)

An application of ultrasonic technique is attempted for the purpose of measuring thin oil film thickness between two surfaces. The amplitude of the wave reflected from the boundary is vary depending on film thickness, because the ultrasonic wave emitted to the interface between two surfaces does multiple reflection and interference in oil film. Quantitative measurement of oil film thickness then can be possible. For instance, it is possible to measure the submicron film thickness which exists near the point contact formed by convex glass and plate with high frequency probe. And it is confirmed that the oil film thickness estimated from the echo height agrees with the film thickness decided by the curvature of the lens or obtained by the optical interference method, even if it is 100 nm. On the other hand, the thickness of oil film between cylinder and piston ring can be easily measured by setting the small ultrasonic probe on the back of piston ring. For example, the influence of the second ring and oil ring for the behavior of an oil film formed on a top ring is able to evaluate quantitatively. As mentioned above, it is cleared that quantitative evaluation of thin film thickness is possible with investigating the echo height obtained by ultrasonic wave pulse reflection method.

Takeuchi, Akitoshi; Terada, Seiichi; Toda, So

47

Thermal properties measurements in biodiesel oils using photothermal techniques  

NASA Astrophysics Data System (ADS)

In this Letter, thermal lens and open cell photoacoustic techniques are used to measure the thermal properties of biodiesel oils. The absolute values of the thermal effusivity, thermal diffusivity, thermal conductivity and the temperature coefficient of the refractive index were determined for samples obtained from soy, castor bean, sunflower and turnip. The results suggest that the employed techniques may be useful as complementary methods for biodiesel certification.

Castro, M. P. P.; Andrade, A. A.; Franco, R. W. A.; Miranda, P. C. M. L.; Sthel, M.; Vargas, H.; Constantino, R.; Baesso, M. L.

2005-08-01

48

Equilibrium gas-oil ratio measurements using a microfluidic technique.  

PubMed

A method for measuring the equilibrium GOR (gas-oil ratio) of reservoir fluids using microfluidic technology is developed. Live crude oils (crude oil with dissolved gas) are injected into a long serpentine microchannel at reservoir pressure. The fluid forms a segmented flow as it travels through the channel. Gas and liquid phases are produced from the exit port of the channel that is maintained at atmospheric conditions. The process is analogous to the production of crude oil from a formation. By using compositional analysis and thermodynamic principles of hydrocarbon fluids, we show excellent equilibrium between the produced gas and liquid phases is achieved. The GOR of a reservoir fluid is a key parameter in determining the equation of state of a crude oil. Equations of state that are commonly used in petroleum engineering and reservoir simulations describe the phase behaviour of a fluid at equilibrium state. Therefore, to accurately determine the coefficients of an equation of state, the produced gas and liquid phases have to be as close to the thermodynamic equilibrium as possible. In the examples presented here, the GORs measured with the microfluidic technique agreed with GOR values obtained from conventional methods. Furthermore, when compared to conventional methods, the microfluidic technique was simpler to perform, required less equipment, and yielded better repeatability. PMID:23657610

Fisher, Robert; Shah, Mohammad Khalid; Eskin, Dmitry; Schmidt, Kurt; Singh, Anil; Molla, Shahnawaz; Mostowfi, Farshid

2013-07-01

49

Simulation of particle agglomeration using dissipative particle dynamics  

E-print Network

of the agglomerates resulting from the different types of attractive forces is performed to characterize them methodically. Also as a part of this thesis, a novel, dynamic particle simulation technique was developed by interfacing MATLAB and our computational C...

Mokkapati, Srinivas Praveen

2009-05-15

50

Fragmentation and bond strength of airborne diesel soot agglomerates  

PubMed Central

Background The potential of diesel soot aerosol particles to break up into smaller units under mechanical stress was investigated by a direct impaction technique which measures the degree of fragmentation of individual agglomerates vs. impact energy. Diesel aerosol was generated by an idling diesel engine used for passenger vehicles. Both the aerosol emitted directly and aerosol that had undergone additional growth by Brownian coagulation ("aging") was investigated. Optionally a thermo-desoption technique at 280°C was used to remove all high-volatility and the majority of low-volatility HC adsorbates from the aerosol before aging. Results It was found that the primary soot agglomerates emitted directly from the engine could not be fragmented at all. Soot agglomerates permitted to grow additionally by Brownian coagulation of the primary emitted particles could be fragmented to a maximum of 75% and 60% respectively, depending on whether adsorbates were removed from their surface prior to aging or not. At most, these aged agglomerates could be broken down to roughly the size of the agglomerates from the primary emission. The energy required for a 50% fragmentation probability of all bonds within an agglomerate was reduced by roughly a factor of 2 when aging "dry" agglomerates. Average bond energies derived from the data were 0.52*10-16 and 1.2*10-16 J, respectively. This is about 2 orders of magnitude higher than estimates for pure van-der-Waals agglomerates, but agrees quite well with other observations. Conclusion Although direct conclusions regarding the behavior of inhaled diesel aerosol in contact with body fluids cannot be drawn from such measurements, the results imply that highly agglomerated soot aerosol particles are unlikely to break up into units smaller than roughly the size distribution emitted as tail pipe soot. PMID:18533015

Rothenbacher, Sonja; Messerer, Armin; Kasper, Gerhard

2008-01-01

51

Hydrophobic Agglomeration of Mineral Fines in Aqueous Suspensions and its Application in Flotation: a Review  

NASA Astrophysics Data System (ADS)

Hydrophobic agglomeration is originated from the hydrophobic attraction between particles, which is essentially different from electrolyte coagulation and polymer flocculation. It is applied to mineral processing in floc-flotation process to improve the recovery of mineral fines. In this paper, the applications of this phenomenon in mineral fines were summarized, including the origin of hydrophobic agglomeration, the main factors affect hydrophobic agglomeration (particle hydrophobicity, shear rate and duration, nonpolar oil and tank geometry), as well as hydrophobic agglomeration based separation processes (carrier flotation and floc-flotation).

Yang, Bingqiao; Song, Shaoxian

2014-05-01

52

Comparison of screening techniques for polychlorinated biphenyls in waste oils  

SciTech Connect

A commercial colorimetric field screening kit for the detection of polychlorinated biphenyls (PCBs) is compared to instrumental thermal neutron activation analysis as a screening tool in a variety of oil matrices. The precision of these two methods was compared to an accepted method of analysis, gas chromatography with electron capture detection, and interferences of each screening technique were investigated. The colorimetric test was shown to be less reliable and more prone to interferences than neutron activation analysis. The advantages and limitations of each method are discussed.

Sutcliffe, C.R.; Gladney, E.S.; Seitz, D.M.; Brooks, G.H. (Los Alamos National Lab., NM (USA))

1989-12-01

53

Direct olive oil authentication: detection of adulteration of olive oil with hazelnut oil by direct coupling of headspace and mass spectrometry, and multivariate regression techniques.  

PubMed

Control of adulteration of olive oil, together with authentication and contamination, is one of the main aspects in the quality control of olive oil. Adulteration with hazelnut oil is one of the most difficult to detect due to the similar composition of hazelnut and olive oils; both virgin olive oil and olive oil are subjected to that kind of adulteration. The main objective of this work was to develop an analytical method able to detect adulteration of virgin olive oils and olive oils with hazelnut oil by means of its analysis by a headspace autosampler directly coupled to a mass spectrometer used as detector (ChemSensor). As no chromatographic separation of the individual components of the samples exists, a global signal of the sample is obtained and employed for its characterization by means of chemometric techniques. Four different crude hazelnut oils from Turkey were employed for the development of the method. Multivariate regression techniques (partial least squares and principal components analysis) were applied to generate adequate regression models. Good values were obtained in both techniques for the parameters employed (standard errors of prediction (SEP) and prediction residual error sum of squares (PRESS)) to evaluate its goodness. With the proposed method, minimum adulteration levels of 7 and 15% can be detected in refined and virgin olive oils, respectively. Once validated, the method was applied to the detection of such adulteration in commercial olive oil and virgin olive oil samples. PMID:15941058

Peña, Fernando; Cárdenas, Soledad; Gallego, Mercedes; Valcárcel, Miguel

2005-05-13

54

Recent Advances in Agglomerated Multigrid  

NASA Technical Reports Server (NTRS)

We report recent advancements of the agglomerated multigrid methodology for complex flow simulations on fully unstructured grids. An agglomerated multigrid solver is applied to a wide range of test problems from simple two-dimensional geometries to realistic three- dimensional configurations. The solver is evaluated against a single-grid solver and, in some cases, against a structured-grid multigrid solver. Grid and solver issues are identified and overcome, leading to significant improvements over single-grid solvers.

Nishikawa, Hiroaki; Diskin, Boris; Thomas, James L.; Hammond, Dana P.

2013-01-01

55

Microbial effects on colloidal agglomeration  

SciTech Connect

Colloidal particles are known to enhance the transport of radioactive metals through soil and rock systems. This study was performed to determine if a soil microorganism, isolated from the surface samples collected at Yucca Mountain, NV, could affect the colloidal properties of day particles. The agglomeration of a Wyoming bentonite clay in a sterile uninoculated microbial growth medium was compared to the agglomeration in the medium inoculated with a Pseudomonas sp. In a second experiment, microorganisms were cultured in the succinate medium for 50 h and removed by centrifugation. The agglomeration of the clay in this spent was compared to sterile uninoculated medium. In both experiments, the agglomeration of the clay was greater than that of the sterile, uninoculated control. Based on these results, which indicate that this microorganism enhanced the agglomeration of the bentonite clay, it is possible to say that in the presence of microorganisms colloidal movement through a rock matrix could be reduced because of an overall increase in the size of colloidal particle agglomerates. 32 refs.

Hersman, L.

1995-11-01

56

Flocculation, hydrophobic agglomeration and filtration of ultrafine coal  

NASA Astrophysics Data System (ADS)

In coal preparation plant circuits, fine coal particles are aggregated either by oil agglomeration or by flocculation. In a new hydrophobic agglomeration process, recently developed hydrophobic latices are utilized. While the selectivity of such aggregation processes determines the beneficiation results, the degree of aggregation has a strong effect on fine coal filtration. The aim of this research was to study the fundamentals and analyze the common grounds for these processes, including the potential effect of the coal surface properties. The selective flocculation tests, in which three types of coal, which differed widely in surface wettability, and three additives (hydrophobic latices, a semi-hydrophobic flocculant and a typical hydrophilic polyelectrolyte) were utilized, showed that coal wettability plays a very important role in selective flocculation. The abstraction of a hydrophobic latex on coal and silica revealed that the latex had a much higher affinity towards hydrophobic coal than to hydrophilic mineral matter. As a result, the UBC-1 hydrophobic latex flocculated only hydrophobic coal particles while the polyelectrolyte (PAM) flocculated all the tested coal samples and minerals, showing no selectivity in the fine coal beneficiation. The oil agglomeration was tested using kerosene emulsified with various surfactants (e.g. cationic, anionic and non-ionic). Surfactants enhance not only oil emulsification, hence reducing oil consumption (down to 0.25--0.5%), but also entirely change the electrokinetic properties of the droplets and affect the interaction energy between oil droplets and coal particles. Consequently, the results found in the course of the experimental work strongly indicate that even oxidized coals can be agglomerated if cationic surfactants are used to emulsify the oil. Oil agglomeration of the Ford-4 ultrafine coal showed that even at extremely low oil consumption (0.25 to 0.5%), a clean coal product with an ash content around 5% at over 99.9% coal recovery could be obtained in a one-stage separation by screening the agglomerated product. If a conventional oil agglomeration process is used instead, oil consumption as high as 30% is needed to obtain comparable results. In the tests on filtration and dewatering of ultrafine and fine coals, the effect of chemical additives and coal surface properties was investigated. The tests revealed very significant differences in the filtration of ultrafine (-45 mum) and fine (-500 mum) coals. The moisture contents in the filter cakes in the tests with ultrafine coal were around 40% (irrespective of the coal surface properties), while for the fine coal the moisture content fluctuated around 18% (Ford-4) and 30% (Ford-13). The results revealed that the hydrophobic latex and the emulsified oils could not only successfully beneficiate the ultrafine coal but also significantly increase filtration rate and/or reduce moisture content of the filter cake. Among the chemicals tested, the emulsified oils were found to be the most promising not only for the beneficiation but also for filtration and dewatering processes. Surfactants were found to only slightly affect the filtration of fine coal. However, they can influence filtration very profoundly if utilized to emulsify the oil which is used to agglomerate coal prior to its filtration.

Yu, Zhimin

57

Treatment of oil spill by sorption technique using fatty acid grafted sawdust.  

PubMed

Treatment of oil spills remains a challenge to environmental scientists and technologists. Among all the existing techniques used for oil treatment, sorption is a popular technique because it is cheap, simple and effective. Among the various sorbents used, sawdust appears to be the most attractive material in terms of cost, versatility and abundance. In the present work, the efficacy of surface modification of sawdust by fatty acids (oleic acid, stearic acid and decanoic acid) and vegetable oils (castor oil or mustard oil) is demonstrated. Sorption of seawater contaminated with crude oil and also weathered oil was greatly enhanced by the surface modification. The results show that oleic acid grafted sawdust (OGSD) has the best sorption capacity for crude oil as well as weathered oil. PMID:16542707

Banerjee, Shashwat S; Joshi, Milind V; Jayaram, Radha V

2006-08-01

58

Air agglomeration of hydrophobic particles  

SciTech Connect

The agglomeration of hydrophobic particles in an aqueous suspension was accomplished by introducing small amounts of air into the suspension while it was agitated vigorously. The extent of aggregation was proportional both to the air to solids ratio and to the hydrophobicity of the solids. For a given air/solids ratio, the extent of aggregation of different materials increased in the following order: graphite, gilsonite, coal coated with heptane, and Teflon. The structure of agglomerates produced from coarse Teflon particles differed noticeably from the structure of bubble-particle aggregates produced from smaller, less hydrophobic particles.

Drzymala, J.; Wheelock, T.D.

1995-12-31

59

Fractal analysis of soot agglomerates. Final report, June 1986-June 1987  

SciTech Connect

The fractal behavior of soot agglomerates formed by the combustion of acetylene in a coannular diffusion burner is studied. Structural data from electron micrographs were obtained by two methods: the first by particle counting with the aid of stereopairs for small clusters, and the second by electronic digitization with advanced image-processing techniques, used for the larger agglomerates. An average agglomerate length to width ratio of about 1.7 with a standard deviation of 0.6 was obtained. The agglomerates were found to have a fractal dimension D of about 1.8-1.9 based on measurements of the pair-correlation function for large agglomerates and 1.5-1.6 based on measurements of the radius of gyration for small agglomerates. These results are compared with recent computer simulations as well as experimental studies of inorganic smokes.

Samson, R.J.

1988-06-01

60

Agglomeration, Integration and Tax Harmonization  

Microsoft Academic Search

This Paper considers tax competition and tax harmonization in the presence of agglomeration forces and falling trade costs. With agglomerative forces operating, industry is not indifferent to location in equilibrium, so perfectly mobile capital becomes a quasi-fixed factor. This suggests that the tax game is something subtler than a race to the bottom. Advanced 'core' nations may act like limit-pricing

Richard E. Baldwin; Paul Krugman

2000-01-01

61

Composite propellant combustion with low aluminum agglomeration.  

E-print Network

??Aluminum behavior???accumulation, agglomeration and ignition???is studied in a unique, wide-distribution, ammonium perchlorate/hydroxyl-terminated polybutadiene (AP/HTPB) propellant formulation that results in low Al agglomeration, even at low… (more)

Mullen, Jessica C.

2010-01-01

62

Agglomerate behaviour of fluticasone propionate within dry powder inhaler formulations.  

PubMed

Due to their small size, the respirable drug particles tend to form agglomerates which prevent flowing and aerosolisation. A carrier is used to be mixed with drug in one hand to facilitate the powder flow during manufacturing, in other hand to help the fluidisation upon patient inhalation. Depending on drug concentration, drug agglomerates can be formed in the mixture. The aim of this work was to study the agglomeration behaviour of fluticasone propionate (FP) within interactive mixtures for inhalation. The agglomerate phenomenon of fluticasone propionate after mixing with different fractions of lactose without fine particles of lactose (smaller than 32 ?m) was demonstrated by the optical microscopy observation. A technique measuring the FP size in the mixture was developed, based on laser diffraction method. The FP agglomerate sizes were found to be in a linear correlation with the pore size of the carrier powder bed (R(2)=0.9382). The latter depends on the particle size distribution of carrier. This founding can explain the role of carrier size in de-agglomeration of drug particles in the mixture. Furthermore, it gives more structural information of interactive mixture for inhalation that can be used in the investigation of aerosolisation mechanism of powder. According to the manufacturing history, different batches of FP show different agglomeration intensities which can be detected by Spraytec, a new laser diffraction method for measuring aerodynamic size. After mixing with a carrier, Lactohale LH200, the most cohesive batch of FP, generates a lower fine particle fraction. It can be explained by the fact that agglomerates of fluticasone propionate with very large size was detected in the mixtures. By using silica-gel beads as ball-milling agent during the mixing process, the FP agglomerate size decreases accordingly to the quantity of mixing aid. The homogeneity and the aerodynamic performance of the mixtures are improved. The mixing aid based on ball-milling effect could be used to ameliorate the quality of inhalation mixture of cohesive drug, such as fluticasone propionate. However, there is a threshold where an optimal amount of mixing aids should be used. Not only the drug des-aggregation reaches its peak but the increase in drug-carrier adhesion due to high energy input should balance the de-agglomeration capacity of mixing process. This approach provides a potential alternative in DPI formulation processing. PMID:22198291

Le, V N P; Robins, E; Flament, M P

2012-04-01

63

Application of petroleum hydrocarbon chemical fingerprinting and allocation techniques after the Exxon Valdez oil spill  

Microsoft Academic Search

Advances in environmental chemistry laboratory and data interpretation techniques (i.e. chemical fingerprinting) contributed to a better understanding of the biological impact of the 1989 Exxon Valdez oil spill and the fate of the spilled oil. A review of the evolution of petroleum chemical fingerprinting techniques is presented followed by a summarization of how new approaches were used to characterize and

Paul D. Boehm; Gregory S. Douglas; William A. Burns; Paul J. Mankiewicz; David S. Page; A. Edward Bence

1997-01-01

64

Metal Agglomeration in Solid Propellants Combustion  

Microsoft Academic Search

The theoretical model or metal agglomeration in solid propellants comhustion is developed. The derivation of the basic integral equation for agglomeration theory is produced. The analytical solution of the equation for monodisperse initial metal powder is obtained. The effect of different factors on the agglomeration process are investigated. The comparison with known experimental data is carried out.

S. A. RASHKOVSKY

1998-01-01

65

Cleaning of Indian coals by agglomeration with xylene and hexane  

Microsoft Academic Search

A laboratory scale agglomeration process has been undertaken for cleaning Indian coals using oils namely, xylene and hexane. Maximum organic matter recovery for xylene has been found to be 91.9% whereas with hexane, the value is 54.7% on a dry basis. The highest ash rejection values with xylene (90.7%) and with hexane (89.7%) are almost same. Promising results for rejection

Mrinal K Baruah; Probhat Kotoky; Jyotish Baruah; Gobin C Bora

2000-01-01

66

A technique for evaluating the oil/heavy-oil viscosity changes under ultrasound in a simulated porous medium.  

PubMed

Theoretically, Ultrasound method is an economical and environmentally friendly or "green" technology, which has been of interest for more than six decades for the purpose of enhancement of oil/heavy-oil production. However, in spite of many studies, questions about the effective mechanisms causing increase in oil recovery still existed. In addition, the majority of the mechanisms mentioned in the previous studies are theoretical or speculative. One of the changes that could be recognized in the fluid properties is viscosity reduction due to radiation of ultrasound waves. In this study, a technique was developed to investigate directly the effect of ultrasonic waves (different frequencies of 25, 40, 68 kHz and powers of 100, 250, 500 W) on viscosity changes of three types of oil (Paraffin oil, Synthetic oil, and Kerosene) and a Brine sample. The viscosity calculations in the smooth capillary tube were based on the mathematical models developed from the Poiseuille's equation. The experiments were carried out for uncontrolled and controlled temperature conditions. It was observed that the viscosity of all the liquids was decreased under ultrasound in all the experiments. This reduction was more significant for uncontrolled temperature condition cases. However, the reduction in viscosity under ultrasound was higher for lighter liquids compare to heavier ones. Pressure difference was diminished by decreasing in the fluid viscosity in all the cases which increases fluid flow ability, which in turn aids to higher oil recovery in enhanced oil recovery (EOR) operations. Higher ultrasound power showed higher liquid viscosity reduction in all the cases. Higher ultrasound frequency revealed higher and lower viscosity reduction for uncontrolled and controlled temperature condition experiments, respectively. In other words, the reduction in viscosity was inversely proportional to increasing the frequency in temperature controlled experiments. It was concluded that cavitation, heat generation, and viscosity reduction are three of the promising mechanisms causing increase in oil recovery under ultrasound. PMID:24075416

Hamidi, Hossein; Mohammadian, Erfan; Junin, Radzuan; Rafati, Roozbeh; Manan, Mohammad; Azdarpour, Amin; Junid, Mundzir

2014-02-01

67

Powder agglomeration in a microgravity environment  

NASA Technical Reports Server (NTRS)

This is the final report for NASA Grant NAG3-755 entitled 'Powder Agglomeration in a Microgravity Environment.' The research program included both two types of numerical models and two types of experiments. The numerical modeling included the use of Monte Carlo type simulations of agglomerate growth including hydrodynamic screening and molecular dynamics type simulations of the rearrangement of particles within an agglomerate under a gravitational field. Experiments included direct observation of the agglomeration of submicron alumina and indirect observation, using small angle light scattering, of the agglomeration of colloidal silica and aluminum monohydroxide. In the former class of experiments, the powders were constrained to move on a two-dimensional surface oriented to minimize the effect of gravity. In the latter, some experiments involved mixture of suspensions containing particles of opposite charge which resulted in agglomeration on a very short time scale relative to settling under gravity.

Cawley, James D.

1994-01-01

68

Study of Oil spill in Norwegian area using Decomposition Techniques on RISAT-1 Hybrid Polarimetric Data.  

NASA Astrophysics Data System (ADS)

Over past few years Synthetic Aperture Radar(SAR) has received a considerable attention for monitoring and detection of oil spill due to its unique capabilities to provide wide-area surveillance and day and night measurements, almost independently from atmospheric conditions. The critical part of the oil spill detection is to distinguish oil spills from other natural phenomena. Stokes vector analysis of the image data is studied to estimate the polarized circular and linear components of the backscatter signal which essentially utilize the degree of polarization(m) and relative phase (?) of the target. In a controlled oil spill experiment conducted at Norwegian bay during 17th to 22nd June 2014, RISAT-1 hybrid polarimetry images were utilized to study the characteristics of oil spill in the sea. The preliminary results obtained by using polarimetric decomposition technique on hybrid polarimetric data to decipher the polarimetric characteristics of oil spills from natural waters are discussed in the paper.

Jayasri, P. V.; Usha Sundari, H. S. V.; Kumari, E. V. S. Sita; Prasad, A. V. V.

2014-11-01

69

Boundary-layer transition and global skin friction measurement with an oil-fringe imaging technique  

NASA Technical Reports Server (NTRS)

A new oil-fringe imaging system skin friction (FISF) technique to measure skin friction on wind tunnel models is presented. In the method used to demonstrate the technique, lines of oil are applied on surfaces that connect the intended sets of measurement points, and then a wind tunnel is run so that the oil thins and forms interference fringes that are spaced in proportion to local skin friction. After a run the fringe spacings are imaged with a CCD-array digital camera and measured on a computer. Skin friction and transition measurements on a two-dimensional wing are presented and compared with computational predictions.

Monson, Daryl J.; Mateer, George G.; Menter, Florian R.

1993-01-01

70

Ignition technique for an in situ oil shale retort  

DOEpatents

A generally flat combustion zone is formed across the entire horizontal cross-section of a fragmented permeable mass of formation particles formed in an in situ oil shale retort. The flat combustion zone is formed by either sequentially igniting regions of the surface of the fragmented permeable mass at successively lower elevations or by igniting the entire surface of the fragmented permeable mass and controlling the rate of advance of various portions of the combustion zone.

Cha, Chang Y. (Golden, CO)

1983-01-01

71

Improved techniques for fluid diversion in oil recovery. Final report  

SciTech Connect

This three-year project had two technical objectives. The first objective was to compare the effectiveness of gels in fluid diversion (water shutoff) with those of other types of processes. Several different types of fluid-diversion processes were compared, including those using gels, foams, emulsions, particulates, and microorganisms. The ultimate goals of these comparisons were to (1) establish which of these processes are most effective in a given application and (2) determine whether aspects of one process can be combined with those of other processes to improve performance. Analyses and experiments were performed to verify which materials are the most effective in entering and blocking high-permeability zones. The second objective of the project was to identify the mechanisms by which materials (particularly gels) selectively reduce permeability to water more than to oil. A capacity to reduce water permeability much more than oil or gas permeability is critical to the success of gel treatments in production wells if zones cannot be isolated during gel placement. Topics covered in this report include (1) determination of gel properties in fractures, (2) investigation of schemes to optimize gel placement in fractured systems, (3) an investigation of why some polymers and gels can reduce water permeability more than oil permeability, (4) consideration of whether microorganisms and particulates can exhibit placement properties that are superior to those of gels, and (5) examination of when foams may show placement properties that are superior to those of gels.

Seright, R.

1996-01-01

72

Micro-agglomerate flotation for deep cleaning of coal. Final report  

SciTech Connect

The development of practical technologies for the deep cleaning of coal has been seriously hampered by the problems of carrying out efficient coal/mineral separations at the very fine sizes (often finer than 10 {micro}m) needed to achieve adequate liberation of the mineral matter from the coal matrix. In this investigation a hybrid process--Micro-agglomerate flotation--which is a combination of oil-agglomeration and froth flotation was studied. The basic concept is to use small quantities of oil to promote the formation of dense micro-agglomerates with minimal entrapment of water and mineral particles and to use froth flotation to separate these micro-agglomerates from the water/dispersed-mineral phase. Since the floating units will be relatively large agglomerates (30--50 {micro}m in size) rather than fine coal particles (1--10 {micro}m) the problems of froth overload and water/mineral carryover should be significantly alleviated. There are, however, complications. The process involves at least five phases: two or more solids (coal and mineral), two liquids (oil and water) and one gas (air). It is demonstrated in this study that the process is very sensitive to fluctuations in operating parameters. It is necessary to maintain precise control over the chemistry of the liquid phases as well as the agitation conditions in order to promote selectivity. Both kinetics as well as thermodynamic factors play a critical role in determining overall system response.

Chander, S.; Hogg, R.

1997-01-15

73

Assessing Agglomeration Impacts in Auckland: Phase 1  

Microsoft Academic Search

Vigorous debate around Auckland's role in the New Zealand economy continues. By examining the presence of agglomeration effects in Auckland, this paper presents a new set of relationships by which Auckland's productivity performance can be considered. The major finding of the paper is that agglomeration effects, stemming from the densification of employment activity, have contributed to Auckland's relatively strong productivity

John Williamson; Richard Paling; Ramon Staheli; David Waite

2008-01-01

74

Development of acoustic agglomerator: Final report  

SciTech Connect

The Aerojet Energy Conversion Company has conducted a program to develop a system for removal of particulates from a hot gas stream. The system was based on acoustic agglomeration, and it had to be suitable for cleaning the effluent gas stream from a coal-burning, pressurized fluid bed combustor (PFBC). The hot gas cleanup system with acoustic agglomeration (HGCU AA) used high intensity acoustic waves to pre-condition the hot aerosol by causing the smaller particles to agglomerate, or form clusters, with the larger particles. Conventional cyclones can then be used to remove the particulate matter from the aerosol more effectively since the smaller particles have, in effect, been ''removed'' by their agglomerating with the larger particles. After agglomerating and becoming larger, the particles can be more effectively removed by cyclones. 14 refs., 61 figs., 14 tabs.

Not Available

1987-11-01

75

Engineering development of selective agglomeration. Final report  

SciTech Connect

This report presents the findings of the project entitled ``Engineering Development of Selective Agglomeration.`` The purpose is to develop selective agglomeration technology to a commercially acceptable level by 1993. Engineering development included bench-scale process development, component development adaptation or modification of existing unit operations, proof-of-concept (POC) module design, fabrication, testing, data evaluation, and conceptual design of a commercial facility. The information obtained during POC operation resulted in a technical and economic design base sufficient to support construction and operation of a commercial plant. Throughout this project performance targets for the engineering development of selective agglomeration process were to achieve 85% or greater Btu recovery at 85% or greater pyritic sulfur rejection (PSR). Additional objectives included producing a final clean-coal product with an ash content of 6% or less which is suitable for conventional coal handling systems. The selective agglomeration process, as applied to coal cleaning, is based on differences in the surface chemistry of coal and its associated impurities. Coal particles are hydrophobic (i.e., repel water) while the majority of its impurities are hydrophilic (i.e., stabilized in water). During selective agglomeration, a liquid (the agglomerant) that is immiscible with water is introduced into a coal-water slurry and agitated to disperse it in the slurry, thereby allowing it to come into contact with all particles in the slurry. The coal particles, due to their hydrophobic nature, are attracted to the agglomerant phase. The hydrophilic mineral impurities remain in the water phase. Continued agitation of the agglomerant-coated coal particles causes them to coalesce to form agglomerates. Once the agglomerates are formed, they are separated from the mineral matter-bearing aqueous phase by subsequent processing steps.

Not Available

1993-04-01

76

Rapid and nondestructive determination of seed oil by pulsed nuclear magnetic resonance technique  

Microsoft Academic Search

The pulsed NMR technique for rapid and nondestructive determination of oil in oilseeds has been developed. The effects of\\u000a spin-lattice relaxation time, spin-spin relaxation time, seed moisture, angular position of the seeds, sample tube thickness,\\u000a and sample height upon the magnitude and reproducibility of the NMR signal were studied. Based upon these studies, various\\u000a parameters for seed oil analysis have

P. N. Tiwari; P. N. Gambhir; T. S. Rajan

1974-01-01

77

Transformation of Resources to Reserves: Next Generation Heavy-Oil Recovery Techniques  

SciTech Connect

This final report and technical progress report describes work performed from October 1, 2004 through September 30, 2007 for the project 'Transformation of Resources to Reserves: Next Generation Heavy Oil Recovery Techniques', DE-FC26-04NT15526. Critical year 3 activities of this project were not undertaken because of reduced funding to the DOE Oil Program despite timely submission of a continuation package and progress on year 1 and 2 subtasks. A small amount of carried-over funds were used during June-August 2007 to complete some work in the area of foamed-gas mobility control. Completion of Year 3 activities and tasks would have led to a more thorough completion of the project and attainment of project goals. This progress report serves as a summary of activities and accomplishments for years 1 and 2. Experiments, theory development, and numerical modeling were employed to elucidate heavy-oil production mechanisms that provide the technical foundations for producing efficiently the abundant, discovered heavy-oil resources of the U.S. that are not accessible with current technology and recovery techniques. Work fell into two task areas: cold production of heavy oils and thermal recovery. Despite the emerging critical importance of the waterflooding of viscous oil in cold environments, work in this area was never sanctioned under this project. It is envisioned that heavy oil production is impacted by development of an understanding of the reservoir and reservoir fluid conditions leading to so-called foamy oil behavior, i.e, heavy-oil solution gas drive. This understanding should allow primary, cold production of heavy and viscous oils to be optimized. Accordingly, we evaluated the oil-phase chemistry of crude oil samples from Venezuela that give effective production by the heavy-oil solution gas drive mechanism. Laboratory-scale experiments show that recovery correlates with asphaltene contents as well as the so-called acid number (AN) and base number (BN) of the crude oil. A significant number of laboratory-scale tests were made to evaluate the solution gas drive potential of West Sak (AK) viscous oil. The West Sak sample has a low acid number, low asphaltene content, and does not appear foamy under laboratory conditions. Tests show primary recovery of about 22% of the original oil in place under a variety of conditions. The acid number of other Alaskan North Slope samples tests is greater, indicating a greater potential for recovery by heavy-oil solution gas drive. Effective cold production leads to reservoir pressure depletion that eases the implementation of thermal recovery processes. When viewed from a reservoir perspective, thermal recovery is the enhanced recovery method of choice for viscous and heavy oils because of the significant viscosity reduction that accompanies the heating of oil. One significant issue accompanying thermal recovery in cold environments is wellbore heat losses. Initial work on thermal recovery found that a technology base for delivering steam, other hot fluids, and electrical heat through cold subsurface environments, such as permafrost, was in place. No commercially available technologies are available, however. Nevertheless, the enabling technology of superinsulated wells appears to be realized. Thermal subtasks focused on a suite of enhanced recovery options tailored to various reservoir conditions. Generally, electrothermal, conventional steam-based, and thermal gravity drainage enhanced oil recovery techniques appear to be applicable to 'prime' Ugnu reservoir conditions to the extent that reservoir architecture and fluid conditions are modeled faithfully here. The extent of reservoir layering, vertical communication, and subsurface steam distribution are important factors affecting recovery. Distribution of steam throughout reservoir volume is a significant issue facing thermal recovery. Various activities addressed aspects of steam emplacement. Notably, hydraulic fracturing of horizontal steam injection wells and implementation of steam trap control that limits steam entry into hor

Stanford University; Department of Energy Resources Engineering Green Earth Sciences

2007-09-30

78

An effective ostrich oil bleaching technique using peroxide value as an indicator.  

PubMed

Ostrich oil has been used extensively in the cosmetic and pharmaceutical industries. However, rancidity causes undesirable chemical changes in flavour, colour, odour and nutritional value. Bleaching is an important process in refining ostrich oil. Bleaching refers to the removal of certain minor constituents (colour pigments, free fatty acid, peroxides, odour and non-fatty materials) from crude fats and oils to yield purified glycerides. There is a need to optimize the bleaching process of crude ostrich oil prior to its use for therapeutic purposes. The objective of our study was to establish an effective method to bleach ostrich oil using peroxide value as an indicator of refinement. In our study, we showed that natural earth clay was better than bentonite and acid-activated clay to bleach ostrich oil. It was also found that 1 hour incubation at a 150 °C was suitable to lower peroxide value by 90%. In addition, the nitrogen trap technique in the bleaching process was as effective as the continuous nitrogen flow technique and as such would be the recommended technique due to its cost effectiveness. PMID:21730920

Palanisamy, Uma Devi; Sivanathan, Muniswaran; Radhakrishnan, Ammu Kutty; Haleagrahara, Nagaraja; Subramaniam, Thavamanithevi; Chiew, Gan Seng

2011-01-01

79

Agglomeration tendency in dry pharmaceutical granular systems.  

PubMed

The agglomeration tendency of dry pharmaceutical mixtures containing various concentrations of Xylitab 100 (Xylitol), calcium carbonate precipitated (CCP) and magnesium stearate (MgSt) was evaluated statistically as a function of mixing time. A Ro-Tap tester was employed to mix the three pharmaceutical components, and the agglomerates formed were measured with respect to their weight and size. An experimental design was devised and applied to structure and then statistically analyze the results. Xylitab was found not to be influential in the formation of agglomerates, but aided in deagglomeration when mixed with other components. CCP and MgSt formed agglomerates over time and showed positive interactions favouring agglomeration. The agglomerates started to fracture when they reached a critical size, at which stage the particles' attraction forces (cohesion forces) were weaker than both gravity and inertia. It has been shown and quantitatively demonstrated that the mixing time and ingredient concentrations of a three-component pharmaceutical mixture can affect agglomeration tendency. PMID:16797949

Lachiver, Emilie DesRosiers; Abatzoglou, Nicolas; Cartilier, Louis; Simard, Jean-Sébastien

2006-10-01

80

Shapes of agglomerates in plasma etching reactors  

SciTech Connect

Dust particle contamination of wafers in reactive ion etching (RIE) plasma tools is a continuing concern in the microelectronics industry. It is common to find that particles collected on surfaces or downstream of the etch chamber are agglomerates of smaller monodisperse spherical particles. The shapes of the agglomerates vary from compact, high fractal dimension structures to filamentary, low fractal dimension structures. These shapes are important with respect to the transport of particles in RIE tools under the influence electrostatic and ion drag forces, and the possible generation of polarization forces. A molecular dynamics simulation has been developed to investigate the shapes of agglomerates in plasma etching reactors. We find that filamentary, low fractal dimension structures are generally produced by smaller ({lt}100s nm) particles in low powered plasmas where the kinetic energy of primary particles is insufficient to overcome the larger Coulomb repulsion of a compact agglomerate. This is analogous to the diffusive regime in neutral agglomeration. Large particles in high powered plasmas generally produce compact agglomerates of high fractal dimension, analogous to ballistic agglomeration of neutrals. {copyright} {ital 1997 American Institute of Physics.}

Huang, F.Y.; Kushner, M.J. [University of Illinois, Department of Electrical and Computer Engineering, 1406 West Green Street, Urbana, Illinois 61801 (United States)] [University of Illinois, Department of Electrical and Computer Engineering, 1406 West Green Street, Urbana, Illinois 61801 (United States)

1997-05-01

81

Segmentation Techniques for Identification and Tracking of Oil Spills in Ocean Surface M. Gonzalo-Tasis* a  

E-print Network

Segmentation Techniques for Identification and Tracking of Oil Spills in Ocean Surface M. Gonzalo for self-location, correction of effects arising from skew projections and an evaluation of oil spills in the environment by the oil spill in the ocean. The increase of the marine traffic in zones of straits is a factor

Llanos, Diego R.

82

Development of methods to predict agglomeration and disposition in FBCs  

SciTech Connect

This 3-year, multiclient program is providing the information needed to determine the behavior of inorganic components in FBC units using advanced methods of analysis coupled with bench-scale combustion experiments. The major objectives of the program are as follows: (1) To develop further our advanced ash and deposit characterization techniques to quantify the effects of the liquid-phase components in terms of agglomerate formation and ash deposits, (2) To determine the mechanisms of inorganic transformations that lead to bed agglomeration and ash deposition in FBC systems, and (3) To develop a better means to predict the behavior of inorganic components as a function of coal composition, bed material characteristics, and combustion conditions.

Mann, M.D.; Henderson, A.K.; Swanson, M.K.; Erickson, T.A.

1995-11-01

83

Microwave hydrodiffusion and gravity, a new technique for extraction of essential oils.  

PubMed

A new process design and operation for the extraction of essential oils was developed. Microwave hydrodiffusion and gravity (MHG) is a combination of microwaves for hydrodiffusion of essential oils from the inside to the exterior of biological material and earth gravity to collect and separate. MHG is performed at atmospheric pressure without adding any solvent or water. MHG has been compared with a conventional technique, hydrodistillation (HD), for the extraction of essential oil from two aromatic herbs: spearmint (Mentha spicata L.) and pennyroyal (Mentha pulegium L.) belonging to the Labiatae family. The essential oils extracted by MHG for 15 min were quantitatively (yield) and qualitatively (aromatic profile) similar to those obtained by conventional hydrodistillation for 90 min. MHG also prevents pollution through potential 90% of energy saved which can lead to greenhouse gas emission benefits. PMID:18343393

Vian, Maryline Abert; Fernandez, Xavier; Visinoni, Franco; Chemat, Farid

2008-05-01

84

Bed material agglomeration during fluidized bed combustion  

SciTech Connect

The purpose of this project is to determine the physical and chemical reactions which led to the undesired agglomeration of bed material during fluidized bed combustion and to relate these reactions to specific causes. Survey of industrial-scale fluidized bed combustors is being conducted to determine the occurrence of bed agglomeration and the circumstances under which agglomeration took place. This task should be finished by the end of February. Samples of bed material, agglomerate material, and boiler deposits are being requested from boiler operators as part of the survey. Once received, these sample will be analyzed to determine chemical and mineralogic composition. The bulk chemical determination will be performed using x-ray fluorescence and inductively coupled plasma-optical emission (ICP). Mineralogy will be detected by x-ray diffraction (XRD). Chemical and mineral reactions will be determined by scanning electron microscopy, optical microscopy, and electron microprobe.

Brown, R.C.; Dawson, M.R.; Noble, S.

1993-02-01

85

Agglomeration of microparticles in complex plasmas  

SciTech Connect

Agglomeration of highly charged microparticles was observed and studied in complex plasma experiments carried out in a capacitively coupled rf discharge. The agglomeration was caused by strong waves triggered in a particle cloud by decreasing neutral gas pressure. Using a high-speed camera during this unstable regime, it was possible to resolve the motion of individual microparticles and to show that the relative velocities of some particles were sufficiently high to overcome the mutual Coulomb repulsion and hence to result in agglomeration. After stabilizing the cloud again through the increase of the pressure, we were able to observe the aggregates directly with a long-distance microscope. We show that the agglomeration rate deduced from our experiments is in good agreement with theoretical estimates. In addition, we briefly discuss the mechanisms that can provide binding of highly charged microparticles in a plasma.

Du, Cheng-Ran; Thomas, Hubertus M.; Ivlev, Alexei V.; Konopka, Uwe; Morfill, Gregor E. [Max Plank Institute for Extraterrestrial Physics, Garching 85741 (Germany)

2010-11-15

86

Successfully use agglomeration for size enlargement  

SciTech Connect

The processing of fine and ultrafine particles by size enlargement finds an ever increasing application. At the same time, undesirable agglomeration such as buildup, caking, bridging, and uncontrolled aggregation of fine particles can occur during processing and handling of these particulate solids. This article will provide a survey of the phenomena of agglomeration and discuss the unit operation of size enlargement by agglomeration. This article is also an invitation, particularly to young engineers, to become interested in agglomeration. Considering that mechanical process technologies are requiring more energy every year than any other group of consumers and efficiencies are typically in the single digits or teens at best, considerable rewards can be expected from the development of scientifically modified, more energy-efficient methods and equipment.

Pietsch, W. [COMPACTCONSULT, Inc., Naples, FL (United States)

1996-04-01

87

Instrumentation and diagnostic techniques used by Los Alamos National Laboratory in fragmentation experiments in oil shale  

SciTech Connect

Discussed are the instrumentation and diagnostic techniques used to evaluate the explosive fragmentation experiments in oil shale at the Colony and Anvil Points Mines in Colorado. These experiments were conducted to investigate some of the many parameters that control the fragmenting or rubblizing of oil shale in preparation for subsurface retorting. Framing and TV cameras were used to study the size and speed of the ejected shale fragments. Stress and accelerometer gauges provided quantitative data about the explosively induced stress field in the rock. The CORRTEX technique was used to determine the detonation velocity of the explosive and the induced fracture velocity in the oil shale. Postshot measurements included the crater dimensions and rubble size distribution. In addition preshot and postshot geological mapping was done to relate fractures and joints to crater size and shape.

Edwards, C.L.; Adams, T.F.; Dick, R.D.

1981-01-01

88

Composite propellant combustion with low aluminum agglomeration  

NASA Astrophysics Data System (ADS)

Aluminum behavior---accumulation, agglomeration and ignition---is studied in a unique, wide-distribution, ammonium perchlorate/hydroxyl-terminated polybutadiene (AP/HTPB) propellant formulation that results in low Al agglomeration, even at low pressures (1--30 atm). Variations in formulation---such as fine-AP/binder ratio, Al particle size, Al loading, coarse-AP size---are also examined. A fuel-rich, oxygenated binder matrix highly loaded with fine (2-mum) AP (FAP) at 75/25:FAP/binder (by mass) is found to have premixed flame conditions that produce minimal agglomeration (without ignition) of 15-mum Al. Coarse AP (CAP) is added to the system in the form of either particles (200 or 400 mum) or pressed-AP laminates (simulated CAP). In the 2-D laminate system the CAP/oxyfuel-matrix flame structure is seen to be similar to that previously described for non-aluminized laminates with split (diffusion) and merged (partially-premixed) flame regimes, depending on pressure and fuel-matrix thickness. Both laminate and particulate systems show that with CAP present, Al can agglomerate more extensively on CAP via lateral surface migration from fuel matrix to the CAP region. The particulate CAP system also shows that Al can accumulate/agglomerate via settling on CAP from above (in the direction of burning). Both systems, but more clearly the 2-D laminates, show that with CAP present, Al is ignited by the outer CAP/fuel-matrix canopy flames. Thus, a propellant formulation is proposed for reducing overall Al agglomeration through intrinsically reduced agglomeration in the fuel-matrix and a reduced number of CAP-particle agglomerates via higher FAP/CAP ratio.

Mullen, Jessica Christine

89

Simulation of Agglomerate Dispersion in Combustion of Aluminized Solid Propellants  

Microsoft Academic Search

The paper deals with mathematical simulation of dispersion of agglomerates formed in combustion of aluminized solid propellants. A substantial effect of the separation conditions of agglomerating metal particles from the surface of the burning propellant on the size of agglomerates is demonstrated. A mathematical model of agglomerate formation is constructed for propellants whose typical feature is active burning of the

V. A. Babuk; I. N. Dolotkazin; V. V. Sviridov

2003-01-01

90

Oil-spill removal techniques and equipment. (Latest citations from Fluidex data base). Published Search  

SciTech Connect

The bibliography contains citations concerning equipment and techniques for the control, dispersal, cleanup, and disposal of oil spills. Topics include chemical dispersants, booms, and mechanical skimmers. The citations emphasize spill removal for harbors, estuaries, and shorelines, and examine spill impact on water birds and marine life. (Contains a minimum of 180 citations and includes a subject term index and title list.)

Not Available

1992-09-01

91

Oil spill removal techniques and equipment. (Latest citations from Fluidex). Published Search  

SciTech Connect

The bibliography contains citations concerning equipment and techniques for the control, dispersal, cleanup, and disposal of oil spills. Topics include chemical dispersants, booms, and mechanical skimmers. The citations emphasize spill removal for harbors, estuaries, and shorelines, and examine spill impact on water birds and marine life. (Contains a minimum of 195 citations and includes a subject term index and title list.)

Not Available

1993-12-01

92

Oil spill removal techniques and equipment. (Latest citations from Oceanic abstracts). Published Search  

SciTech Connect

The bibliography contains citations concerning equipment and techniques used for control, detection, dispersion, and disposal of oil spills particularly within harbors and estuaries. Topics include chemical dispersants, mechanical skimmers, and biodegradation. The citations also explore spill impact on habitats, marine life, and water birds. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1993-12-01

93

Oil spill removal techniques and equipment. (Latest citations from Oceanic abstracts). Published Search  

SciTech Connect

The bibliography contains citations concerning equipment and techniques used for control, detection, dispersion, and disposal of oil spills particularly within harbors and estuaries. Topics include chemical dispersants, mechanical skimmers, and biodegradation. The citations also explore spill impact on habitats, marine life, and water birds. (Contains 250 citations and includes a subject term index and title list.)

NONE

1995-01-01

94

Prudhoe Bay Oil Production Optimization: Using Virtual intelligence Techniques, Stage One: Neural Model Building  

E-print Network

between the production separation facilities and central gas compression plant. The trained modelSPE 77659 Prudhoe Bay Oil Production Optimization: Using Virtual intelligence Techniques, Stage One and at the gas compression plant. The correlation coefficient for rate and pressure were 0.997 and 0

Mohaghegh, Shahab

95

Kinetic energy density and agglomerate abrasion rate during blending of agglomerates into powders.  

PubMed

Problems related to the blending of a cohesive powder with a free flowing bulk powder are frequently encountered in the pharmaceutical industry. The cohesive powder often forms lumps or agglomerates which are not dispersed during the mixing process and are therefore detrimental to blend uniformity. Achieving sufficient blend uniformity requires that the blending conditions are able to break up agglomerates, which is often an abrasion process. This study was based on the assumption that the abrasion rate of agglomerates determines the required blending time. It is shown that the kinetic energy density of the moving powder bed is a relevant parameter which correlates with the abrasion rate of agglomerates. However, aspects related to the strength of agglomerates should also be considered. For this reason the Stokes abrasion number (St(Abr)) has been defined. This parameter describes the ratio between the kinetic energy density of the moving powder bed and the work of fracture of the agglomerate. The St(Abr) number is shown to predict the abrasion potential of agglomerates in the dry-mixing process. It appeared possible to include effects of filler particle size and impeller rotational rate into this concept. A clear relationship between abrasion rate of agglomerates and the value of St(Abr) was demonstrated. PMID:22127372

Willemsz, Tofan A; Hooijmaijers, Ricardo; Rubingh, Carina M; Tran, Thanh N; Frijlink, Henderik W; Vromans, Herman; van der Voort Maarschalk, Kees

2012-01-23

96

The extraction and chromatographic determination of the essentials oils from Ocimum basilicum L. by different techniques  

NASA Astrophysics Data System (ADS)

Three different techniques (maceration, sonication and extraction in microwave field) were used for extraction of essential oils from Ocimum basilicum L. The extracts were analyzed by TLC/HPTLC technique and the fingerprint informations were obtained. The GC-FID was used to characterized the extraction efficiency and for identify the terpenic bioactive compounds. The most efficient extraction technique was maceration followed by microwave and ultrasound. The best extraction solvent system was ethyl ether + ethanol (1:1, v/v). The main compounds identified in Ocimum basilicum L. extracts were: ? and ?-pinene (mixture), limonene, citronellol, and geraniol.

Loredana Soran, Maria; Codruta Cobzac, Simona; Varodi, Codruta; Lung, Ildiko; Surducan, Emanoil; Surducan, Vasile

2009-08-01

97

A New Screening Methodology for Improved Oil Recovery Processes Using Soft-Computing Techniques  

NASA Astrophysics Data System (ADS)

The first stage of production of any oil reservoir involves oil displacement by natural drive mechanisms such as solution gas drive, gas cap drive and gravity drainage. Typically, improved oil recovery (IOR) methods are applied to oil reservoirs that have been depleted naturally. In more recent years, IOR techniques are applied to reservoirs even before their natural energy drive is exhausted by primary depletion. Descriptive screening criteria for IOR methods are used to select the appropriate recovery technique according to the fluid and rock properties. This methodology helps in assessing the most suitable recovery process for field deployment of a candidate reservoir. However, the already published screening guidelines neither provide information about the expected reservoir performance nor suggest a set of project design parameters, which can be used towards the optimization of the process. In this study, artificial neural networks (ANN) are used to build a high-performance neuro-simulation tool for screening different improved oil recovery techniques: miscible injection (CO2 and N2), waterflooding and steam injection processes. The simulation tool consists of proxy models that implement a multilayer cascade feedforward back propagation network algorithm. The tool is intended to narrow the ranges of possible scenarios to be modeled using conventional simulation, reducing the extensive time and energy spent in dynamic reservoir modeling. A commercial reservoir simulator is used to generate the data to train and validate the artificial neural networks. The proxy models are built considering four different well patterns with different well operating conditions as the field design parameters. Different expert systems are developed for each well pattern. The screening networks predict oil production rate and cumulative oil production profiles for a given set of rock and fluid properties, and design parameters. The results of this study show that the networks are able to recognize the strong correlation between the displacement mechanism and the reservoir characteristics as they effectively forecast hydrocarbon production for different types of reservoir undergoing diverse recovery processes. The artificial neuron networks are able to capture the similarities between different displacement mechanisms as same network architecture is successfully applied in both CO2 and N2 injection. The neuro-simulation application tool is built within a graphical user interface to facilitate the display of the results. The developed soft-computing tool offers an innovative approach to design a variety of efficient and feasible IOR processes by using artificial intelligence. The tool provides appropriate guidelines to the reservoir engineer, it facilitates the appraisal of diverse field development strategies for oil reservoirs, and it helps to reduce the number of scenarios evaluated with conventional reservoir simulation.

Parada, Claudia; Ertekin, Turgay

2010-05-01

98

Comparing Parameter Estimation Techniques for an Electrical Power Transformer Oil Temperature Prediction Model  

NASA Technical Reports Server (NTRS)

This paper examines various sources of error in MIT's improved top oil temperature rise over ambient temperature model and estimation process. The sources of error are the current parameter estimation technique, quantization noise, and post-processing of the transformer data. Results from this paper will show that an output error parameter estimation technique should be selected to replace the current least squares estimation technique. The output error technique obtained accurate predictions of transformer behavior, revealed the best error covariance, obtained consistent parameter estimates, and provided for valid and sensible parameters. This paper will also show that the output error technique should be used to minimize errors attributed to post-processing (decimation) of the transformer data. Models used in this paper are validated using data from a large transformer in service.

Morris, A. Terry

1999-01-01

99

Increased Oil Production and Reserves from Improved Completion Techniques in the Bluebell Field, Uinta Basin, Utah.  

SciTech Connect

The objective of this project is to increase oil production and reserves in the Uinta Basin by demonstrating improved completion techniques. Low productivity of Uinta Basin wells is caused by gross production intervals of several thousand feet that contain perforated thief zones, water-bearing zones, and unperforated oil-bearing intervals. Geologic and engineering characterization and computer simulation of the Green River and Wasatch Formations in the Bluebell field will determine reservoir heterogeneities related to fractures and depositional trends. This will be followed by drilling and recompletion of several wells to demonstrate improved completion techniques based on the reservoir characterization. Transfer of the project results will be an ongoing component of the project.

Morgan, C.D.

1997-12-31

100

Increased Oil Production and Reserves from Improved Completion Techniques in the Bluebell Field, Uinta Basin, Utah  

SciTech Connect

The objective of this project is to increase oil production and reserves in the Uinta Basin by demonstrating improved completion techniques. Low productivity of Uinta Basin wells is caused by gross production intervals of several thousand feet that contain perforated thief zones, water-bearing zones, and non-perforated oil-bearing intervals. Geologic and engineering characterization and computer simulation of the Green River and Wasatch Formations in the Bluebell field will determine reservoir heterogeneities related to fractures and depositional trends. This will be followed by drilling and recompletion of several wells to demonstrate improved completion techniques based on the reservoir characterization. Transfer of the project results will be an ongoing component of the project.

Deo, Milind D.; Morgan, Craig D.

1999-11-01

101

DETERMINATION OF STOKES SHAPE FACTOR FOR SINGLE PARTICLES AND AGGLOMERATES  

SciTech Connect

The large octahedral crystals of spinel can precipitate from glass during the high-level waste vitrification process and potentially block the glass discharge riser of electrically heated ceramic melters. To help predict the settling behavior of spinel in the riser, the settling of single particles and agglomerates was studied in stagnant and transparent viscosity oils at room temperature with developed optical particle-dynamics-analyzer. Determined dimensions and terminal settling velocities of particles were used for calculation of their Stokes shape factors. Calculated shape factor for the glass beads was almost identical with the theoretical shape factor of 2/9 for a perfect sphere. The shape factor for single spinel crystal was about 7.6 % higher compare to the theoretically predicted value for octahedron. Stokes shape factor of irregularly shaped multi-particle agglomerates was lower than that of the glass beads and individual spinel crystals because of the higher surface drag caused by the larger surface area to volume ratio.

Matyas, Josef; Schaible, Micah J.; Vienna, John D.

2011-09-01

102

Oil spill removal techniques and equipment. (Latest citations from fluidex). Published Search  

SciTech Connect

The bibliography contains citations concerning the development and assessment of techniques and equipment used to control and remove oil spills. Chemical dispersants, booms, and mechanical skimmers are reviewed. Topics include recovery operations, emergency response, frogmat systems, bioremediation, and environmental monitoring. The effects of spills on marine life and fishing industries are examined. (Contains 50-250 citations and includes a subject term index and title list.)

NONE

1995-06-01

103

Migration and agglomeration of heliumatoms in copper  

NASA Astrophysics Data System (ADS)

The magration and agglomeration of Helium atoms in He irradiated Cu was studied between 10 K and 900 K by perturbed ?? angular correlation (PAC) measurements using the radioactive probe atom111In. Trapping of interstitial and substitutional He atoms is observed already after irradiation at 10 K. Substitutional He (He-yacancy pair) is bound in the nearest neighbourhood to the111In probe atom and seems to be stable up to 725 K (E{He1V1/b}?2.1 eV). The onset of vacancy assisted He agglomeration in Cu is observed at 250 K.

Grübel, G.; Deicher, M.; Keller, R.; Korinth, Th.; Reiner, W.; Recknagel, E.; Wichert, Th.

1987-04-01

104

Flotation and agglomerate concentration of nonmetallic minerals  

Microsoft Academic Search

This paper discusses the flotation of phosphates, limestone, magnesite and dolomite, graphite, coal, carbons and chars, bituminous sands, fluorite, zircon, talc, barite, kyanite, chromite, cassiterite, feldspar, beryl, spodumene, nephelite, quartz, mica, sericite, clay, bauxite, tungsten minerals, ilmenite and rutile, manganese ore, oxidized iron ore, sulfur, cryolite, and alunite and alumina. The agglomeration of phosphate, limestone, soluble salines, kyanite, fluorite, and

Ralston

1938-01-01

105

Spatial competition and agglomeration in urban modelling  

Microsoft Academic Search

Many forms of urban models are retail oriented, that is, they depend to some degree on the allocation of shopping expenditures to particular destinations. Such an allocation is usually undertaken with the aid of a production-constrained gravity model, although this type of model ignores the relationship between retail expenditure patterns and spatial competition and agglomeration forces. The effect of such

A S Fotheringham

1985-01-01

106

Control of agglomerate attributes in a continuous binder-agglomeration process  

Microsoft Academic Search

The scope of agglomeration processing includes many different materials over wide scales of production, from specialty materials and pharmaceuticals made in kg\\/day batches to continuous processes for detergents and fertilizers measured in tons\\/h. Agglomeration adds value to the product, for example, producing free-flowing, dust-free particles that are optimized for uses such as tableting, dispersion\\/dissolution and compact delivery (i.e., increase the

Paul R Mort; Scott W Capeci; James W Holder

2001-01-01

107

Agglomeration in bio-fuel fired fluidized bed combustors  

Microsoft Academic Search

This paper presents results from systematic agglomeration experiments in a straw-fired laboratory-scale fluidized bed combustor and a theoretical study of the phenomena. Experiments were carried out at different operating conditions. Defluidization resulting from agglomeration occurred in all experiments. The agglomeration tendency is represented by the time before defluidization is detected. The results show that the temperature has a pronounced effect

Weigang Lin; Kim Dam-Johansen; Flemming Frandsen

2003-01-01

108

Effect of temperature on wet agglomeration of crystals  

PubMed Central

Objective(s): This study dealt with the wet agglomeration process in which a small quantity of binder liquid was added into a suspension of crystals, directly in the stirring vessel where the crystallization took place. The purpose of this investigation was evaluation of the effect of temperature on the agglomeration process in order to gain insight into the mechanism of the formation of the agglomerates. Materials and Methods: Carbamazepine was used as a model drug and water/ethanol and isopropyl acetate were used as crystallization system and binder liquid, respectively. The agglomeration of crystals was carried out at various temperatures and the agglomerates were characterized in terms of size, morphology, density and mechanical strength. Results: Evaluation of the agglomerates along the course of agglomeration shows that the properties of the particles change gradually but substantially. Higher temperature of the system during agglomeration process favors the formation of more regular agglomerates with mechanically stronger and denser structure; this can be explained by the promotion effect of temperature on the agglomeration process. Conclusion: With optimized wet agglomeration temperature, spherical, dense, and strong agglomerates can be obtained. PMID:24967063

Maghsoodi, Maryam; Yari, Zahra

2014-01-01

109

Method for providing improved solid fuels from agglomerated subbituminous coal  

DOEpatents

A method is provided for separating agglomerated subbituminous coal and the heavy bridging liquid used to form the agglomerates. The separation is performed by contacting the agglomerates with inert gas or steam at a temperature in the range of 250.degree. to 350.degree. C. at substantially atmospheric pressure.

Janiak, Jerzy S. (Edmonton, CA); Turak, Ali A. (Edmonton, CA); Pawlak, Wanda (Edmonton, CA); Ignasiak, Boleslaw L. (Edmonton, CA)

1989-01-01

110

Chemical and physicochemial properties of submicron aerosol agglomerates  

SciTech Connect

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory. The formation of nanometer-sized aerosol particles in a premixed methane flame from both solid-phase aerosol precursors and gas-phase precursors was investigated. Techniques were developed to determine the distribution of the individual chemical species as a function of agglomerate size by using inductively coupled plasma atomic emission spectroscopy (ICP-AES). To determine the distribution of chemical species both from particle to particle and within the particles on a nanometer scale, we used the analytical electron microscopy techniques of energy dispersive x-ray spectrometry (EDS) and electron energy loss spectrometry (EELS) coupled with transmission electron microscopy (TEM). The observed distribution of individual chemical species as a function of agglomerate size was linked to the material properties of the solid-phase precursors. For aerosol formed from gas-phase precursors by gas-to-particle conversion, the distribution of species on a manometer scale was found to correspond to the equilibrium phase distribution expected from equilibrium for the system at the flame temperatures.

Scripsick, R.C. [Los Alamos National Lab., NM (United States); Ehrman, S.; Friedlander, S.K. [Univ. of California, Los Angeles, CA (United States). Dept. of Chemical Engineering

1998-12-31

111

Comparison of soft computing techniques for a three-phase oil field centrifuge.  

SciTech Connect

In this work we compare fuzzy techniques to neural network techniques for building a soft sensor for a three-phase oil field centrifuge. The soft sensor is used in a feed-forward control system that augments a feedback control system. Two approaches were used to develop the soft sensor. The first approach was to use a fuzzy rule based system based upon the experience of an expert operator. The expert operator's experience was supplemented using a computer model of the system. The second approach was to use a neural network to build the inverse of the computer model. The pros and cons of both techniques are discussed. KEYWORDS: fuzzy logic, neural networks, soft sensor, soft computing

Smith, R. E. (Ronald E.); Parkinson, w; Miller, N. (Neal)

2002-01-01

112

Understanding agglomeration of indomethacin during the dissolution of micronised indomethacin mixtures through dissolution and de-agglomeration modeling approaches.  

PubMed

The purpose of this research was to correlate the state of agglomeration determined by the modeling of dissolution and de-agglomeration profiles, using mixtures of micronised indomethacin designed to have different dissolution rates and extents of particle agglomeration in dissolution media. Dissolution profiles were determined using the USP paddle method. De-agglomeration profiles were obtained from laser diffraction particle sizing of mixtures of indomethacin in dissolution media under non-sink conditions. Data were modeled and key parameters estimated using a non-linear least squares estimation algorithm. The key parameters of initial apparent volume concentrations as dispersed and agglomerated particles, and dissolution rate constants (for dissolution modeling), and the apparent volume concentrations of dispersible and non-dispersible agglomerates and the de-agglomeration rate constant (for de-agglomeration modeling) were related to indomethacin and sodium lauryl sulphate concentrations in the lactose-povidone mixtures. Micronised sodium lauryl sulphate added to the mixture was more effective in de-agglomeration than equivalent concentrations in the dissolution media. An excellent correlation existed between the total initial apparent volume concentration of agglomerates determined by dissolution and de-agglomeration (P=0.98). The use of key parameters estimated from the modeling of dissolution and de-agglomeration profiles provides a useful tool in dosage form development of formulations of poorly water soluble drugs. PMID:15661504

Stewart, Peter J; Zhao, Feng-Ying

2005-02-01

113

Increased Oil Production and Reserves from Improved Completion Techniques in the Bluebell Field, Uinta Basin, Utah  

SciTech Connect

The objective of the project is to increase oil production and reserves by the use of improved reservoir characterization and completion techniques in the Uinta Basin, Utah. To accomplish this objective, a two-year geologic and engineering characterization of the Bluebell field was conducted. The study evaluated surface and subsurface data, currently used completion techniques, and common production problems. It was determined that advanced case- and open-hole logs could be effective in determining productive beds and that stage-interval (about 500 ft [150 m] per stage) and bed-scale isolation completion techniques could result in improved well performance. In the first demonstration well (Michelle Ute well discussed in the previous technical report), dipole shear anisotropy (anisotropy) and dual-burst thermal decay time (TDT) logs were run before and isotope tracer log was run after the treatment. The logs were very helpful in characterizing the remaining hydrocarbon potential in the well. But, mechanical failure resulted in a poor recompletion and did not result in a significant improvement in the oil production from the well.

Deo, M.D.; Morgan, C.D.

1999-04-28

114

Modeling Agglomeration of Dust Particles in Plasma  

SciTech Connect

The charge on an aggregate immersed in a plasma environment distributes itself over the aggregate's surface; this can be approximated theoretically by assuming a multipole distribution. The dipole-dipole (or higher order) charge interactions between fractal aggregates lead to rotations of the grains as they interact. Other properties of the dust grains also influence the agglomeration process, such as the monomer shape (spherical or ellipsoidal) or the presence of magnetic material. Finally, the plasma and grain properties also determine the morphology of the resultant aggregates. Porous and fluffy aggregates are more strongly coupled to the gas, leading to reduced collisional velocities, and greater collisional cross sections. These factors in turn can determine the growth rate of the aggregates and evolution of the dust cloud. This paper gives an overview of the numerical and experimental methods used to study dust agglomeration at CASPER and highlights some recent results.

Matthews, Lorin S.; Land, Victor; Ma Qianyu; Perry, Jonathan D.; Hyde, Truell W. [Center for Astrophysics, Space Physics, and Engineering Research Baylor University, One Bear Place 97310, Waco, Texas 76798-7310 (United States)

2011-11-29

115

Self-consistent photothermal techniques: Application for measuring thermal diffusivity in vegetable oils  

E-print Network

of vegetable oils. The thermal diffusivity of six commercial vegetable oils olive, corn, soybean, canola century as base lubricants, vegetable oils were gradually replaced by mineral oils mainly for economic in environmental issues.2 A vegetable oil is a complex mixture of chemical substances3 with fatty acids among

Mandelis, Andreas

116

A new generation of electromagnetic and ultrasonic techniques for subsurface evaluation of oil field tubulars  

SciTech Connect

In the past few years, corrosion and mechanical fatigue have been becoming a more visible issue in the oil and gas industry. The issue of lost profits from lost production and the cost and liability resulting from failure has overcome the obvious concern of simple mechanical integrity. A new generation of tool designs have been developed for in-situ evaluation of well casings. These designs along with improvements to existing designs have just recently been introduced to address some of the limitations in subsurface well casing evaluation. These new hardware developments and interpretation techniques can now provide unpredecented accuracy for evaluating downhole tubular conditions. This paper reviews four recent designs while discussing the principals of measurement and offering actual field data in several comparisons. The four designs include: Electromagnetic: AC Types, DC Types, Casing Potential Profiling; Ultrasonic: Ultrasonic Thickness Types. An interpretation technique using sequential measurements to predict and manage for corrosion problems is also presented.

Lewis, R.G.

1988-01-01

117

Oil  

NSDL National Science Digital Library

The first site, offered by the Institute of Petroleum, is called Fossils into Fuel (1). It describes how oil and gas are formed and processed, as well as offering short quizzes on each section. The second site (2) is maintained by the Department of Energy. Visitors can learn about the history of oil use, how itâÂÂs found and extracted, and more. The next site, called Picture an Oil Well (3), is a one-page illustration and description of the workings of an oil well, offered by the California Department of Conservation. The fourth site, hosted by the Minerals Management Service, is called Stacey Visits an Offshore Oil Rig (4). It tells the story of a girl taking a field trip on an offshore oil rig and what she finds when sheâÂÂs there. The Especially for Kids Web site (5) is presented by NOAA and explores facts about the effects of oil spills. Kids can do experiments, get help writing a report, find further information on the provided additional links, and more. From the Environmental Protection Agency, the sixth site is called Oil Spill Program (6), and it also delves into the topic of oil spills. It provides information about the EPA's program for preventing, preparing for, and responding to oil spills that occur in and around inland waters of the United States. The next site, offered by How Stuff Works.com, is called How Oil Refining Works (7). Descriptions of crude oil, fractional distillation, chemical processing, and more is presented in a succinct but informative way. The last site is from The Center for Subsurface Modeling (CSM) of the Texas Institute for Computational and Applied Mathematics and is called CSMâÂÂs Picture Gallery (8). After clicking the Gallery link, visitors will find animations and images that represent CSMâÂÂs work such as oil spill simulations, discontinuous galerkin, the tyranny of scale, contaminant remediation, etc.

Brieske, Joel A.

2002-01-01

118

Uncertainty Analysis for Oil-Film Interferometry Skin-Friction Measurement Techniques  

NASA Technical Reports Server (NTRS)

Over the past 20 years, the use of oil-film interferometry to measure the skin friction coefficient (C(sub f) = tau/q where tau is the surface shear stress and q is the dynamic pressure) has increased. Different forms of this oil-film technique with various levels of accuracy and ease of use have been successfully applied in a wide range of flows. The method's popularity is growing due to its relative ease of implementation and minimal intrusiveness as well as an increased demand for C(sub f) measurements. Nonetheless, the accuracy of these methods has not been rigorously addressed to date. Most researchers have simply shown that the skin-friction measurements made using these techniques compare favorably with other measurements and theory, most of which are only accurate to within 5-20%. The use of skin-friction data in the design of commercial aircraft, whose drag at cruise is 50% skin-friction drag, and in the validation of computational fluid dynamics programs warrants better uncertainty estimates. Additional information is contained in the original extended abstract.

Naughton, Jonathan W.; Brown, James L.; Merriam, Marshal (Technical Monitor)

1996-01-01

119

Water in oil emulsion droplet size characterization using a pulsed field gradient with diffusion editing (PFG-DE) NMR technique.  

PubMed

This paper describes a proton nuclear magnetic resonance (NMR) technique, pulsed field gradient with diffusion editing (PFG-DE), to quantify drop size distributions of brine/crude oil emulsions. The drop size distributions obtained from this technique were compared to results from the traditional pulsed field gradient (PFG) technique. The PFG-DE technique provides both transverse relaxation (T2) and drop size distributions simultaneously. In addition, the PFG-DE technique does not assume a form of the drop size distribution. An algorithm for the selection of the optimal parameters to use in a PFG-DE measurement is described in this paper. The PFG-DE technique is shown to have the ability to resolve drop size distributions when the T2 distribution of the emulsified brine overlaps either the crude oil or the bulk brine T2 distribution. Finally, the PFG-DE technique is shown to have the ability to resolve a bimodal drop size distribution. PMID:17716679

Aichele, Clint P; Flaum, Mark; Jiang, Tianmin; Hirasaki, George J; Chapman, Walter G

2007-11-15

120

An improved technique for modeling initial reservoir hydrocarbon saturation distributions: applications in Illinois (USA) Aux Vases oil reservoirs  

Microsoft Academic Search

An improved technique for modeling the initial reservoir hydrocarbon saturation distributions is presented. In contrast to the Leverett J-function approach, this methodology (hereby termed flow-unit-derived initial oil saturation or FUSOI) determines the distributions of the initial oil saturations from a measure of the mean hydraulic radius, referred to as the flow zone indicator (FZI). FZI is derived from porosity and

Emmanuel Udegbunam; Jude O. Amaefule

1998-01-01

121

Triggered release of ciprofloxacin from nanostructured agglomerated vesicles  

PubMed Central

Nanostructured agglomerated vesicles encapsulating ciprofloxacin were evaluated for modulated delivery from the lungs in a healthy rabbit model. An aliphatic disulfide crosslinker, cleavable by cysteine was used to form cross-links between nanosized liposomes to form the agglomerates. The blood levels of drug after pulmonary instillation of free ciprofloxacin, liposomal ciprofloxacin, and the agglomerated liposomes encapsulating ciprofloxacin were evaluated. The liposomes and agglomerated vesicles showed extended release of drug into the blood over 24 hours, while the free ciprofloxacin did not. The agglomerates also allowed modulation of the drug release rate upon the introduction of cysteine into the lungs post-drug instillation; the cysteine-cleavable agglomerates accelerated their drug release rate, indicated by an increased level of drug in the blood. This technology holds promise for the post-administration modulation of antibiotic release, for the prevention and treatment of pulmonary and systemic infections. PMID:18019839

Bhavane, Rohan; Karathanasis, Efstathios; Annapragada, Ananth V

2007-01-01

122

Analysis and synthesis of solutions for the agglomeration process modeling  

NASA Astrophysics Data System (ADS)

The present work is devoted development of model of agglomerating process for propellants based on ammonium perchlorate (AP), ammonium dinitramide (ADN), HMX, inactive binder, and nanoaluminum. Generalization of experimental data, development of physical picture of agglomeration for listed propellants, development and analysis of mathematical models are carried out. Synthesis of models of various phenomena taking place at agglomeration implementation allows predicting of size and quantity, chemical composition, structure of forming agglomerates and its fraction in set of condensed combustion products. It became possible in many respects due to development of new model of agglomerating particle evolution on the surface of burning propellant. Obtained results correspond to available experimental data. It is supposed that analogical method based on analysis of mathematical models of particular phenomena and their synthesis will allow implementing of the agglomerating process modeling for other types of metalized solid propellants.

Babuk, V. A.; Dolotkazin, I. N.; Nizyaev, A. A.

2013-03-01

123

Oil whip instability control using ?-synthesis technique on a magnetic actuator  

NASA Astrophysics Data System (ADS)

Rotating machines have a wide application range and since those machines have high trust levels, several rotor vibrations control methods are investigated in order to avoid sudden cracks, improve rotor performance or even to reach higher operation speeds by controlling some instabilities, critical speeds resonances or oil whip effect. Rotor instabilities are associated to the operation speed and can have structural or dynamic sources from the shaft, bearings and foundation or even from an actuator external force. This work focuses on a strategy that uses the ?-synthesis control technique to attenuate the oil whip instability effect of flexible hydrodynamically supported rotors and allows the rotor to operate in higher speeds. For the identified rotor model and the synthesized controller applied on a magnetic actuator, the control system stability and performance specifications are analyzed with regard to the model uncertainties and ?-synthesis controlled vibration levels are compared to PID controller in vertical and horizontal directions. The performance specifications within the ?-synthesis are optimized to suppress unbalance vibration and, in order to contribute to industrial acceptance, the controller design is presented as a strategy which focuses on a design at reduced effort.

Riemann, Bernd; Araujo Perini, Efrain; Lucchesi Cavalca, Katia; Fiori de Castro, Helio; Rinderknecht, Stephan

2013-02-01

124

The soundscape dynamics of human agglomeration  

NASA Astrophysics Data System (ADS)

We report on a statistical analysis of the people agglomeration soundscape. Specifically, we investigate the normalized sound amplitudes and intensities that emerge from human collective meetings. Our findings support the existence of non-trivial dynamics characterized by heavy tail distributions in the sound amplitudes, long-range correlations in the sound intensity and non-exponential distributions in the return interval distributions. Additionally, motivated by the time-dependent behavior present in the volatility/variance series, we compare the observational data with those obtained from a minimalist autoregressive stochastic model, namely the generalized autoregressive conditional heteroskedastic process (the GARCH process), and find that there is good agreement.

Ribeiro, Haroldo V.; de Souza, Rodolfo T.; Lenzi, Ervin K.; Mendes, Renio S.; Evangelista, Luiz R.

2011-02-01

125

A landfarming application technique used as environmental remediation for coal oil pollution.  

PubMed

Since the massive exploitation of the Val d'Agri (Basilicata-Italy) oilfield has started, a lot of environmental pollution accidents have occurred in the same region. This research takes as starting point the heavy accident occurred in the year 2000, when 15,150 kg of coal oil were spilt all over the Agri river bed and the surrounding fields. In that particular case, the environmental reclamation was achieved by the removal of the polluted soil and its dump-storage. This research work suggests an environmental restoration which is an alternative solution to what has been practiced before, and it is achieved by the so called bioremediation methods, particularly the "landfarming on site" technique. PMID:12929808

Giasi, Concetta I; Morelli, Annalisa

2003-08-01

126

APPLIED PHYTO-REMEDIATION TECHNIQUES USING HALOPHYTES FOR OIL AND BRINE SPILL SCARS  

SciTech Connect

Produced salt water from historical oil and gas production was often managed with inadequate care and unfortunate consequences. In Kansas, the production practices in the 1930's and 1940's--before statewide anti-pollution laws--were such that fluids were often produced to surface impoundments where the oil would segregate from the salt water. The oil was pumped off the pits and the salt water was able to infiltrate into the subsurface soil zones and underlying bedrock. Over the years, oil producing practices were changed so that segregation of fluids was accomplished in steel tanks and salt water was isolated from the natural environment. But before that could happen, significant areas of the state were scarred by salt water. These areas are now in need of economical remediation. Remediation of salt scarred land can be facilitated with soil amendments, land management, and selection of appropriate salt tolerant plants. Current research on the salt scars around the old Leon Waterflood, in Butler County, Kansas show the relative efficiency of remediation options. Based upon these research findings, it is possible to recommend cost efficient remediation techniques for slight, medium, and heavy salt water damaged soil. Slight salt damage includes soils with Electrical Conductivity (EC) values of 4.0 mS/cm or less. Operators can treat these soils with sufficient amounts of gypsum, install irrigation systems, and till the soil. Appropriate plants can be introduced via transplants or seeded. Medium salt damage includes soils with EC values between 4.0 and 16 mS/cm. Operators will add amendments of gypsum, till the soil, and arrange for irrigation. Some particularly salt tolerant plants can be added but most planting ought to be reserved until the second season of remediation. Severe salt damage includes soil with EC values in excess of 16 mS/cm. Operators will add at least part of the gypsum required, till the soil, and arrange for irrigation. The following seasons more gypsum will be added and as the soil EC is reduced, plants can be introduced. If rapid remediation is required, a sufficient volume of topsoil, or sand, or manure can be added to dilute the local salinity, the bulk amendments tilled into the surface with added gypsum, and appropriate plants added. In this case, irrigation will be particularly important. The expense of the more rapid remediation will be much higher.

M.L. Korphage; Bruce G. Langhus; Scott Campbell

2003-03-01

127

Method for recovering light hydrocarbons from coal agglomerates  

DOEpatents

A method and apparatus for removing light hydrocarbons, such as heptane, from coal agglomerates includes an enclosed chamber having a substantially horizontal perforate surface therein. The coal agglomerates are introduced into a water bath within the chamber. The agglomerates are advanced over the surface while steam is substantially continuously introduced through the surface into the water bath. Steam heats the water and causes volatilization of the light hydrocarbons, which may be collected from the overhead of the chamber. The resulting agglomerates may be collected at the opposite end from the surface and subjected to final draining processes prior to transportation or use.

Huettenhain, Horst (Benicia, CA); Benz, August D. (Hillsborough, CA); Getsoian, John (Ann Arbor, MI)

1991-01-01

128

Direct optical techniques for the measurement of water content in oil-paper insulation in power transformers  

NASA Astrophysics Data System (ADS)

Paper-oil insulation in power transformers is degraded and gradually damaged due to electrical, chemical, mechanical and moisture factors. It is well established from several studies that moisture is a major source of insulation failure in high voltage power transformers. Measurement and monitoring of moisture is essential to predict life and operation condition for power transformers. This paper presents direct optical measurement of water content at paper insulation immersed in transformer oil inside a test cell, which contains a water source, and a capillary paper bridge to transfer water to the paper inside an oil reservoir. Optical measurement of water content was carried out in the near infrared from 900 to 1500 nm band. Experimental studies of light transmission in transformer oil and water are discussed. The criteria to establish the best optical bands for maximum sensitivities are given. The measurement limitations, calibration procedures and an error analysis are presented. The resulting technique can be used for on-line measurements in electrical apparatus that use oil-paper insulation under large electrical field gradients. The presented method has advantages, since it is a direct and fast technique to measure the water transfer to paper immersed in oil, and it could be applied in compact portable equipment at a low cost.

Rodríguez-Rodríguez, Joaquín H.; Martínez-Piñón, Fernando; Álvarez-Chávez, José A.; Jaramillo-Vigueras, David; Robles-Pimentel, Edgar G.

2011-06-01

129

Method for producing ceramic particles and agglomerates  

DOEpatents

A method for generating spherical and irregularly shaped dense particles of ceramic oxides having a controlled particle size and particle size distribution. An aerosol containing precursor particles of oxide ceramics is directed into a plasma. As the particles flow through the hot zone of the plasma, they melt, collide, and join to form larger particles. If these larger particles remain in the hot zone, they continue melting and acquire a spherical shape that is retained after they exit the hot zone, cool down, and solidify. If they exit the hot zone before melting completely, their irregular shape persists and agglomerates are produced. The size and size distribution of the dense product particles can be controlled by adjusting several parameters, the most important in the case of powder precursors appears to be the density of powder in the aerosol stream that enters the plasma hot zone. This suggests that particle collision rate is responsible for determining ultimate size of the resulting sphere or agglomerate. Other parameters, particularly the gas flow rates and the microwave power, are also adjusted to control the particle size distribution.

Phillips, Jonathan (Santa Fe, NM); Gleiman, Seth S. (Santa Fe, NM); Chen, Chun-Ku (Albuquerque, NM)

2001-01-01

130

Milling of agglomerates in an impact mill.  

PubMed

Milling of agglomerates is one of the common unit operations during preparation of oral dosage forms like capsules and tablets. In literature the breakage of granules is mostly determined after single impact at an ideally formed granule or of single particles. In this paper the breakage behavior of agglomerates after milling with multiple impacts has been studied. It investigates the effects of the formulation and the influences of the mill settings. With respect to the formulation it has been found that both the size of the particles before granulation and the amount of binder used determine the breakage behavior. Both parameters have an influence on the strength of the granule to be milled, where initial particle size has the largest effect. A relation has been found between the strength of granules and the degree of size reduction. Regarding the mill settings, there are no mill parameters which influence the formation of fines independently. Formation of fines is always the result of the total degree of size reduction. It is not possible to achieve a large degree of size reduction without intensive fines formation. The results indicate that it is possible to achieve every desired average particle size. However, when formation of dust has to be reduced, multiple milling steps with separation of in-size particles is necessary. PMID:15158958

Verheezen, Joost J A M; van der Voort Maarschalk, Kees; Faassen, Fried; Vromans, Herman

2004-06-18

131

Advanced analytical techniques for the extraction and characterization of plant-derived essential oils by gas chromatography with mass spectrometry.  

PubMed

In recent years, essential oils have received a growing interest because of the positive health effects of their novel characteristics like antibacterial, antifungal and antioxidant activities. For the extraction of plant-derived essential oils, there is the need of advanced analytical techniques and innovative methodologies. An exhaustive study of hydrodistillation, supercritical fluid extraction, ultrasound- and microwave-assisted extraction, solid-phase microextraction, pressurized liquid extraction, pressurized hot water extraction, liquid-liquid extraction, liquid-phase microextraction, matrix solid-phase dispersion and gas chromatography (one and two dimensional) hyphenated with mass spectrometry for the extraction through various plant species and analysis of essential oils have been provided in this review. Essential oils are composed of mainly terpenes and terpenoids with low-molecular-weight aromatic and aliphatic constituents which are particularly important for public health. This article is protected by copyright. All rights reserved. PMID:25403494

Waseem, Rabia; Low, Kah Hin

2014-11-18

132

Agglomeration Economies and Entrepreneurship in the ICT Industry  

Microsoft Academic Search

In this study indicators of agglomeration economies and their effect on entrepreneurship in the ICT industry are analysed in diverse urban contexts. Agglomeration economies have a stronger impact on new firm formation than on the growth of incumbent firms. Concentration and diversity both have a positive effect on new firm formation as well as on the growth of incumbent firms,

F. G. van Oort; E. Stam

2006-01-01

133

Marshallian Agglomeration Economies and Entrepreneurship: The Spanish Case  

Microsoft Academic Search

This paper analyzes to what extent marshallian agglomeration economies affect the creation of new entrepreneurial ventures at the metropolitan level. The measuring of agglomeration economies is based on the construction of indexes using the methodology of Glaeser and Kerr (2009). The indexes attempt to capture the effects of resource sharing, labor matching and knowledge spillovers according to the taxonomy proposed

Roberto Dopeso Fernandez

2011-01-01

134

Direct observation of oil consumption mechanisms in a production spark ignition engine using fluorescence techniques  

NASA Astrophysics Data System (ADS)

The oil consumption characteristics of a four cylinder, normally aspirated spark-ignition engine were investigated for different piston ring end-gap configurations. A radiotracer was used to perform direct measurement of the oil consumption while Laser-induced Fluorescence (LIF) was used to perform the oil film thickness measurements for consumption predictions using the 'Puddle Theory of Oil Consumption,' which relates oil consumption to second land film thickness and reverse flow through top ring gap. The consumption data was evaluated to determine the impact of top ring end-gap azimuthal location on oil consumption. The film thickness data was used to evaluate the extent to which the oil Puddle Theory predicts variations seen in the actual oil consumption. A tritium radiotracer oil consumption measurement system with an accuracy of 94.6 percent was designed and constructed. This was used to perform direct measurements of the test engine oil consumption in two different test matrices. The first evaluated a piston ring configuration with the rings free to rotate. The second evaluated configurations with the top ring and second piston rings pinned to fix the azimuthal location of the end-gap; the azimuth of the top ring was varied. In the second test matrix, the oil film thickness on the piston's second land was measured, and predictions were made on the basis of that measurement.

Lusted, Roderick M.

1994-05-01

135

Electrostatic charging during a melt agglomeration process.  

PubMed

Lactose monohydrate was melt agglomerated in an 8-l high shear mixer using stearic acid, polyethylene glycol (PEG) 3000, and a mixture of stearic acid and glycerol monostearate as meltable binders. Electrostatic charging during processing at relative air humidities of 35 and 75%, respectively, was estimated from the voltage of a monitoring probe inserted into the mixer. Stearic acid produced a high level of electrostatic charges, whereas PEG 3000 gave rise to a markedly lower level. Addition of glycerol monostearate to the stearic acid reduced the level of electrostatic charges. A correlation was found between the resistivity of the binder and the level of electrostatic charges in the material. With the stearic acid and the binder mixture, the level of electrostatic charges was higher at a low air humidity. The amount of adhesion to the bowl was found to depend on the level of electrostatic charges. PMID:10425354

Eliasen, H; Kristensen, H G; Schaefer, T

1999-07-01

136

Soot agglomeration in isolated, free droplet combustion  

NASA Technical Reports Server (NTRS)

Under the conditions of an isolated, free droplet experiment, hollow, carbonaceous structures, called soot spheres, were observed to form during the atmospheric pressure, low Reynolds number combustion of 1-methylnaphthalene. These structures which are agglomerates composed of smaller spheroidal units result from both thermophoretic effects induced by the envelope flame surrounding each drop and aerodynamic effects caused by changes in the relative gas/drop velocities. A chemically reacting flow model was used to analyze the process of sootshell formation during microgravity droplet combustion. The time-dependent temperature and gas property field surrounding the droplet was determined, and the soot cloud location for microgravity combustion of n-heptane droplets was predicted. Experiments showed that the sooting propensity of n-alkane fuel droplets can be varied through diluent substitution, oxygen-index variations, and ambient pressure reductions.

Choi, M. Y.; Dryer, F. L.; Green, G. J.; Sangiovanni, J. J.

1993-01-01

137

Pulse combusted acoustic agglomeration apparatus and process  

DOEpatents

An improved apparatus and process for removal of particulates entrained in a gas stream are provided. The removal process employs a pulse combustor to provide an acoustic pressure wave to acoustically enhance agglomeration of particulates which may be collected and removed using a conventional separation apparatus. The apparatus may be employed as a direct fired system for improved operation of gas-operated equipment such as a gas turbine, or may, alternatively, be employed as an add-on subsystem for combustion exhaust clean-up. Additionally, added particulates may include a sorbent for effecting sorption of other contaminants such as sulfur. Various other particulates for contaminant removal may also be introduced into the system as exemplified by alkali-gettering agents.

Mansour, Momtaz N. (Columbia, MD); Chandran, Ravi (Ellicott City, MD)

1994-01-01

138

Pulse combusted acoustic agglomeration apparatus and process  

DOEpatents

An improved apparatus and process for removal of particulates entrained in a gas stream are provided. The removal process employs a pulse combustor to provide an acoustic pressure wave to acoustically enhance bimodal agglomeration of particulates which may be collected and removed using a conventional separation apparatus. A particulate having a size different from the size of the particulate in the gas stream to be cleaned is introduced into the system to effectuate the bimodal process. The apparatus may be employed as a direct fired system for improved operation of gas-operated equipment such as a gas turbine, or may, alternatively, be employed as an add-on subsystem for combustion exhaust clean-up. Additionally, the added particulate may be a sorbent for effecting sorption of other contaminants such as sulfur. Various other particulates for contaminant removal may also be introduced into the system as exemplified by alkali-gettering agents.

Mansour, Momtaz N. (Columbia, MD)

1993-01-01

139

Influence of primary particle density in the morphology of agglomerates  

E-print Network

Agglomeration processes occur in many different realms of science such as colloid and aerosol formation or formation of bacterial colonies. We study the influence of primary particle density in agglomerate structure using diffusion-controlled Monte Carlo simulations with realistic space scales through different regimes (DLA and DLCA). The equivalence of Monte Carlo time steps to real time scales is given by Hirsch's hydrodynamical theory of Brownian motion. Agglomerate behavior at different time stages of the simulations suggests that three indices (fractal exponent, coordination number and eccentricity index) characterize agglomerate geometry. Using these indices, we have found that the initial density of primary particles greatly influences the final structure of the agglomerate as observed in recent experimental works.

M. D. Camejo; D. R. Espeso; L. L. Bonilla

2014-07-03

140

Novel Binders and Methods for Agglomeration of Ore  

SciTech Connect

Heap leaching is one of the methods being used to recover metal from low grade ore deposits. The main problem faced during heap leaching is the migration of fine grained particles through the heap, forming impermeable beds which result in poor solution flow. The poor solution flow leads to less contact between the leach solution and the ore, resulting in low recovery rates. Agglomeration of ore into coarse, porous masses prevents fine particles from migrating and clogging the spaces and channels between the larger ore particles. Currently, there is one facility in the United States which uses agglomeration. This operation agglomerates their ore using leach solution (raffinate), but is still experiencing undesirable metal recovery from the heaps due to agglomerate breakdown. The use of a binder, in addition to the leach solution, during agglomeration would help to produce stronger agglomerates that did not break down during processing. However, there are no known binders that will work satisfactorily in the acidic environment of a heap, at a reasonable cost. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. Increasing copper recovery in heap leaching by the use of binders and agglomeration would result in a significant decrease in the amount of energy consumed. Assuming that 70% of all the leaching heaps would convert to using agglomeration technology, as much as 1.64*10{sup 12} BTU per year would be able to be saved if a 25% increase in copper recovery was experienced, which is equivalent to saving approximately 18% of the energy currently being used in leaching heaps. For every week a leach cycle was decreased, a savings of as much as 1.23*10{sup 11} BTU per week would result. This project has identified several acid-resistant binders and agglomeration procedures. These binders and experimental procedures will be able to be used for use in improving the energy efficiency of heap leaching.

S. K. Kawatra; T. C. Eisele; K. A. Lewandowski; J. A. Gurtler

2006-09-30

141

Simple techniques to increase the production yield and enhance the quality of organic rice bran oils.  

PubMed

This study develops simple techniques for increasing production yield and refining of crude RBO (CRBO). It was found that pre-heating of rice bran by hot air oven to reach 60°C before being extracted by screw press machine increased the yield from 4.8 to 8.3%w/w. This paper suggested three simple steps for refining of organic CRBO: (1) filtering using filter papers (2) sedimentation by adding 4%w/v fuller's earth and (3) bleaching by running through a packed column of activated carbon. These steps significantly enhanced the qualities of RBO when compared to CRBO before treatment. It was found that the lightness of oil as indicated by color value (L*) increased from 22.8 to 28.7, gum and wax decreased from 3.6 to 1.3%w/w. However, the simple refining method had no effect on peroxide value and free fatty acid content. Moreover, it slightly induced the loss of oryzanol content from 2.8 to 2.2%w/w. PMID:21178310

Srikaeo, Khongsak; Pradit, Maythawinee

2011-01-01

142

Increased Oil Production and Reserves from Improved Completion Techniques in the Bluebell Field, Uinta Basin, Utah, Class I  

SciTech Connect

The objective of this project was to increase oil production and reserves by the use of improved reservoir characterization and completion techniques in the Unita Basin Utah. To accomplish this objective, a two-year geologic and engineering characterization of the Bluebell field was conducted. The study evaluated surface and subsurface data, currently used completion techniques, and common production problems. It was determined that advanced case- and open-hole logs could be effective in determining productive beds and that staged-interval (about 500 ft [150 m] per stage) and bed-scale isolation completion techniques could result in improved well performance.

Morgan, Craig D.; Gwynn, Wallace; Deo, Milind D.; Jarrard, Richard; Curtice, Richard; Morris, Thomas H.; Smouse, DeForrest; Tripp, Carol N.

2000-01-20

143

Nanostructured natural-based polyelectrolyte multilayers to agglomerate chitosan particles into scaffolds for tissue engineering.  

PubMed

The layer-by-layer (LbL) deposition technique is a self-assembly process that allows the coating of material's surface with nanostructured layers of polyelectrolytes, allowing to control several surface properties. This technique presents some advantages when compared with other thin film assembly techniques, like having the possibility to coat surfaces with complex geometries in mild conditions or to incorporate active compounds. Tissue engineering (TE) involves typically the use of porous biodegradable scaffolds for the temporary support of cells. Such structures can be produced by agglomeration of microspheres that needs to be fixed into a three-dimensional (3D) structure. In this work we suggest the use of LbL to promote such mechanical fixation in free-formed microspheres assemblies and simultaneously to control the properties of its surface. For the proof of concept the biological performance of chitosan/alginate multilayers is first investigated in two-dimensional (2D) models in which the attachment and proliferation of L929 and ATDC5 cells are studied in function of the number of layers and the nature of the final layer. Scaffolds prepared by agglomeration of chitosan particles using the same multilayered system were processed and characterized; it was found that they could support the attachment and proliferation of ATDC5 cells. This study suggests that LbL can be used as a versatile methodology to prepare scaffolds by particle agglomeration that could be suitable for TE applications. PMID:21790302

Miranda, Emanuel Sá; Silva, Tiago H; Reis, Rui L; Mano, João F

2011-11-01

144

Estimating primary productivity of tropical oil palm in Malaysia using remote sensing technique and ancillary data  

NASA Astrophysics Data System (ADS)

The amount of carbon sequestration by vegetation can be estimated using vegetation productivity. At present, there is a knowledge gap in oil palm net primary productivity (NPP) at a regional scale. Therefore, in this study NPP of oil palm trees in Peninsular Malaysia was estimated using remote sensing based light use efficiency (LUE) model with inputs from local meteorological data, upscaled leaf area index/fractional photosynthetically active radiation (LAI/fPAR) derived using UK-DMC 2 satellite data and a constant maximum LUE value from the literature. NPP values estimated from the model was then compared and validated with NPP estimated using allometric equations developed by Corley and Tinker (2003), Henson (2003) and Syahrinudin (2005) with diameter at breast height, age and the height of the oil palm trees collected from three estates in Peninsular Malaysia. Results of this study show that oil palm NPP derived using a light use efficiency model increases with respect to the age of oil palm trees, and it stabilises after ten years old. The mean value of oil palm NPP at 118 plots as derived using the LUE model is 968.72 g C m-2 year-1 and this is 188% - 273% higher than the NPP derived from the allometric equations. The estimated oil palm NPP of young oil palm trees is lower compared to mature oil palm trees (<10 years old), as young oil palm trees contribute to lower oil palm LAI and therefore fPAR, which is an important variable in the LUE model. In contrast, it is noted that oil palm NPP decreases with respect to the age of oil palm trees as estimated using the allomeric equations. It was found in this study that LUE models could not capture NPP variation of oil palm trees if LAI/fPAR is used. On the other hand, tree height and DBH are found to be important variables that can capture changes in oil palm NPP as a function of age.

Kanniah, K. D.; Tan, K. P.; Cracknell, A. P.

2014-10-01

145

Oil spill removal techniques and equipment. (Latest citations from the NTIS bibliographic database). Published Search  

SciTech Connect

The bibliography contains citations concerning methods and equipment used for the containment and removal of oil as a result of oil spill mishaps. Dispersants, separators, skimmers and absorbants are discussed. Related studies regarding film spreading and dispersion are presented. Studies pertaining to shipboard ballast and bilgewater cleaning are excluded. (Contains 250 citations and includes a subject term index and title list.)

Not Available

1993-09-01

146

What Causes Industry Agglomeration? Evidence from Coagglomeration Patterns  

E-print Network

Why do firms cluster near one another? We test Marshall's theories of industrial agglomeration by examining which industries locate near one another, or coagglomerate. We construct pairwise coagglomeration indices for US ...

Ellison, Glenn

147

Fragmentation and restructuring of soft-agglomerates under shear.  

PubMed

Soft-agglomerate restructuring, break-up (or fragmentation) and relaxation are studied in a simple shear flow by a discrete element method (DEM). The agglomerates, held together by van der Waals forces, rotate in the shear flow and are stretched into nearly linear structures (fractal dimension approaches unity) until they fracture at their weakest point resulting in lognormally-shaped fragment size distributions asymptotically. Individual fragments relax in the flow towards more compact agglomerates than the parent ones. The evolution of the average number of particles per fragment is described by generalized scaling laws between shear rate, onset (time-lag) of fragmentation, asymptotic fragment mass and size consistent with experimental and theoretical studies in the literature. The initial effective fractal dimension of the agglomerates influences the final one of the fragments. PMID:19948345

Eggersdorfer, M L; Kadau, D; Herrmann, H J; Pratsinis, S E

2010-02-15

148

An improved technique for modeling initial reservoir hydrocarbon saturation distributions: Applications in Illinois (USA) aux vases oil reservoirs  

USGS Publications Warehouse

An improved technique for modeling the initial reservoir hydrocarbon saturation distributions is presented. In contrast to the Leverett J-function approach, this methodology (hereby termed flow-unit-derived initial oil saturation or FUSOI) determines the distributions of the initial oil saturations from a measure of the mean hydraulic radius, referred to as the flow zone indicator (FZI). FZI is derived from porosity and permeability data. In the FUSOI approach, capillary pressure parameters, S(wir), P(d), and ??, derived from the Brooks and Corey (1966) model [Brooks, R.H., Corey, A.T., 1966. Hydraulic properties of porous media, Hydrology Papers, Colorado State Univ., Ft. Collins, No. 3, March.], are correlated to the FZI. Subsequent applications of these parameters then permit the computation of improved hydrocarbon saturations as functions of FZI and height above the free water level (FWL). This technique has been successfully applied in the Mississippian Aux Vases Sandstone reservoirs of the Illinois Basin (USA). The Aux Vases Zeigler field (Franklin County, IL, USA) was selected for a field-wide validation of this FUSOI approach because of the availability of published studies. With the initial oil saturations determined on a depth-by-depth basis in cored wells, it was possible to geostatistically determine the three-dimensional (3-D) distributions of initial oil saturations in the Zeigler field. The original oil-in-place (OOIP), computed from the detailed initialization of the 3-D reservoir simulation model of the Zeigler field, was found to be within 5.6% of the result from a rigorous material balance method.An improved technique for modeling the initial reservoir hydrocarbon saturation distributions is presented. In contrast to the Leverett J-function approach, this methodology (hereby termed flow-unit-derived initial oil saturation or FUSOI) determines the distributions of the initial oil saturations from a measure of the mean hydraulic radius, referred to as the flow zone indicator (FZI). FZI is derived from porosity and permeability data. In the FUSOI approach, capillary pressure parameters, Swir, Pd, and ??, derived from the Brooks and Corey (1966) model, are correlated to the FZI. Subsequent applications of these parameters then permit the computation of improved hydrocarbon saturations as functions of FZI and height above the free water level (FWL). This technique has been successfully applied in the Mississippian Aux Vases Sandstone reservoirs of the Illinois Basin (USA). The Aux Vases Zeigler field (Franklin County, IL, USA) was selected for a field-wide validation of this FUSOI approach because of the availability of published studies. With the initial oil saturations determined on a depth-by-depth basis in cored wells, it was possible to geostatistically determine the three-dimensional (3-D) distributions of initial oil saturations in the Zeigler field. The original oil-in-place (OOIP), computed from the detailed initialization of the 3-D reservoir simulation model of the Zeigler field, was found to be within 5.6% of the result from a rigorous material balance method.

Udegbunam, E.; Amaefule, J.O.

1998-01-01

149

Acoustic agglomeration of power plant fly ash. Final report  

SciTech Connect

The work has shown that acoustic agglomeration at practical acoustic intensities and frequencies is technically and most likely economically viable. The following studies were performed with the listed results: The physics of acoustic agglomeration is complex particularly at the needed high acoustic intensities in the range of 150 to 160 dB and frequencies in the 2500 Hz range. The analytical model which we developed, although not including nonlinear acoustic efforts, agreed with the trends observed. We concentrated our efforts on clarifying the impact of high acoustic intensities on the generation of turbulence. Results from a special set of tests show that although some acoustically generated turbulence of sorts exists in the 150 to 170 dB range with acoustic streaming present, such turbulence will not be a significant factor in acoustic agglomeration compared to the dominant effect of the acoustic velocities at the fundamental frequency and its harmonics. Studies of the robustness of the agglomerated particles using the Anderson Mark III impactor as the source of the shear stresses on the particles show that the agglomerates should be able to withstand the rigors of flow through commercial cyclones without significant break-up. We designed and developed a 700/sup 0/F tubular agglomerator of 8'' internal diameter. The electrically heated system functioned well and provided very encouraging agglomeration results at acoustic levels in the 150 to 160 dB and 2000 to 3000 Hz ranges. We confirmed earlier results that an optimum frequency exists at about 2500 Hz and that larger dust loadings will give better results. Studies of the absorption of acoustic energy by various common gases as a function of temperature and humidity showed the need to pursue such an investigation for flue gas constituents in order to provide necessary data for the design of agglomerators. 65 references, 56 figures, 4 tables.

Reethof, G.; McDaniel, O.H.

1982-01-01

150

Crystal agglomeration of europium oxalate in reaction crystallization using double-jet semi-batch reactor  

Microsoft Academic Search

The particle agglomeration of europium oxalate was investigated in a double-jet semi-batch reactor over a wide range of operating variables, including the agitation speed, reactant feed rate, and reactant concentration. The size of the agglomerates was directly dictated by the particle collision and supersaturation promoting agglomeration and the fluid shear force inhibiting agglomeration. Thus, with a longer feeding time and

Woo-Sik Kim; Woon-Soo Kim; Kwang-Seok Kim; Joon-Soo Kim; Michael D. Ward

2004-01-01

151

Agglomeration economies and entrepreneurship: testing for spatial externalities in the Dutch ICT industry  

Microsoft Academic Search

Although there is growing evidence on the role of agglomeration economies in the formation and growth of firms, both the concepts of agglomeration economies and entrepreneurship tend to be ambiguously defined and measured in the literature. In this study, we aim to improve the conceptualisations and measures of agglomeration economies and entrepreneurship. Indicators of agglomeration economies are analysed in clearly

Frank G. van Oort

2005-01-01

152

Modelling nano-particle agglomeration using local interactions  

E-print Network

Nano-particle agglomeration plays an important role in processes such as spray drying and particle flame synthesis. These processes have in common that nano-particles collide at low concentrations and get irreversibly linked at the point of contact due to plastic deformation. In this paper, we investigate several models of irreversible connections, which require only local interactions between the colliding nano-particles and thus allow for scalable simulations. The models investigated here connect the particles upon collision by non-bonded strongly attractive interactions, bonded interactions or by binding agents placed at the point of contact. Models using spherically symmetric interactions form compact agglomerates and are therefore unsuitable to study agglomeration. In contrast, models that are either based on both central and angular potentials (type one) or on binding agents (type two) efficiently prevent restructuring of the agglomerates, and are therefore useful for modeling contacts formed by plastic deformation. Moreover, both types of models allow to control the rigidity and by that the degree of restructuring. The first type of model is computationally more efficient at low fractional dimensions of the aggregates, while the second gives easy access to local shear forces, which is important when breaking of agglomerates is to be considered. As example applications, we reproduce the well-known diffusion-limited agglomeration (DLA) and report results on soot aggregation.

Gizem Inci; Axel Arnold; Andreas Kronenburg; Rudolf Weeber

2014-04-30

153

Multi-criteria evaluation technique for SFI site identification of NORMS and oil industry waste disposal--possibilities in Kuwait.  

PubMed

Waste generation and accumulating quantities of oil field waste are a matter of environmental concern. This study proposes the Slurry Fracture Injection (SFI) technique as an alternative waste disposal method. The slurried solids injection waste disposal method is environmentally secure and permanent, leaving no future liabilities that must be risk-evaluated or priced. An entire waste stream comprising ground solids and waste water can be injected into deep and hydraulically secure target strata with no contamination of potable water-bearing formations or formations outside the target zone that may contain resources (gas and oil). The slurry injection method can be used to clean and reclaim landfills, oil pits and granular waste dumps. This article proposes a two-tier screening method for evaluating the feasibility of this technique and the identification of suitable target zones. A stringent environmental and process control monitoring program should complement the planning and operational period to ensure environmental protection, waste containment, and regulatory HSE compliance. PMID:19716646

Ud din, Saif; Oskui, R P; Dusseault, Maurice B; Al Ghadban, A N

2009-10-01

154

DEVELOPMENT OF A VIRTUAL INTELLIGENCE TECHNIQUE FOR THE UPSTREAM OIL INDUSTRY  

SciTech Connect

The objective of the research and development work reported in this document was to develop a Virtual Intelligence Technique for optimization of the Preferred Upstream Management Practices (PUMP) for the upstream oil industry. The work included the development of a software tool for identification and optimization of the most influential parameters in upstream common practices as well as geological, geophysical and reservoir engineering studies. The work was performed in cooperation with three independent producing companies--Newfield Exploration, Chesapeake Energy, and Triad Energy--operating in the Golden Trend, Oklahoma. In order to protect data confidentiality, these companies are referred to as Company One, Two, Three in a randomly selected order. These producing companies provided geological, completion, and production data on 320 wells and participated in frequent technical discussions throughout the project. Research and development work was performed by Gas Technology Institute (GTI), West Virginia University (WVU), and Intelligent Solutions Inc. (ISI). Oklahoma Independent Petroleum Association (OIPA) participated in technology transfer and data acquisition efforts. Deliverables from the project are the present final report and a user-friendly software package (Appendix D) with two distinct functions: a characterization tool that identifies the most influential parameters in the upstream operations, and an optimization tool that seeks optimization by varying a number of influential parameters and investigating the coupled effects of these variations. The electronic version of this report is also included in Appendix D. The Golden Trend data were used for the first cut optimization of completion procedures. In the subsequent step, results from soft computing runs were used as the guide for detailed geophysical and reservoir engineering studies that characterize the cause-and-effect relationships between various parameters. The general workflow and the main performing units were as follows: (1) Data acquisition. (GTI, OIPA, Participating producers.) (2) Development of the virtual intelligence software. (WVU, ISI); (3) Application of the software on the acquired data. (GTI, ISI); (4) Detailed production analysis using conventional engineering techniques and the DECICE neural network software. (GTI) and (5) Detailed seismic analysis using Inspect spectral decomposition package and Hapmson-Russell's EMERGE inversion package. (GTI) Technology transfer took place through several workshops held at offices of the participating companies, at OIPA offices, and presentations at the SPE panel on soft computing applications and at the 2003 annual meeting of Texas Independent Producers and Royalty Owners Association (TIPRO). In addition, results were exhibited at the SPE annual meeting, published in GasTips, and placed on the GTI web page. Results from the research and development work were presented to the producing companies as a list of recommended recompletion wells and the corresponding optimized operations parameters. By the end of the project, 16 of the recommendations have been implemented the majority of which resulted in increased production rates to several folds. This constituted a comprehensive field demonstration with positive results.

Iraj A. Salehi; Shahab D. Mohaghegh; Samuel Ameri

2004-09-01

155

Application of Rosenbrock search technique to reduce the drilling cost of a well in Bai-Hassan oil field  

SciTech Connect

The powerful Rosenbrock search technique, which optimizes both the search directions using the Gram-Schmidt procedure and the step size using the Fibonacci line search method, has been used to optimize the drilling program of an oil well drilled in Bai-Hassan oil field in Kirkuk, Iran, using the twodimensional drilling model of Galle and Woods. This model shows the effect of the two major controllable variables, weight on bit and rotary speed, on the drilling rate, while considering other controllable variables such as the mud properties, hydrostatic pressure, hydraulic design, and bit selection. The effect of tooth dullness on the drilling rate is also considered. Increasing the weight on the drill bit with a small increase or decrease in ratary speed resulted in a significant decrease in the drilling cost for most bit runs. It was found that a 48% reduction in this cost and a 97-hour savings in the total drilling time was possible under certain conditions.

Aswad, Z.A.R.; Al-Hadad, S.M.S.

1983-03-01

156

Increased Oil Production and Reserves Utilizing Secondary/Tertiary Recovery Techniques on Small Reservoirs in the Paradox Basin, Utah  

SciTech Connect

The primary objective of this project is to enhance domestic petroleum production by field demonstration and technology transfer of an advanced- oil-recovery technology in the Paradox basin, southeastern Utah. If this project can demonstrate technical and economic feasibility, the technique can be applied to approximately 100 additional small fields in the Paradox basin alone, and result in increased recovery of 150 to 200 million barrels (23,850,000-31,800,000 m3) of oil. This project is designed to characterize five shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation and choose the best candidate for a pilot demonstration project for either a waterflood or carbon-dioxide-(CO2-) miscible flood project. The field demonstration, monitoring of field performance, and associated validation activities will take place within the Navajo Nation, San Juan County, Utah.

Jr., Chidsey, Thomas C.; Allison, M. Lee

1999-11-02

157

Increased Oil Production and Reserves Utilizing Secondary/Terriary Recovery Techniques on Small Reservoirs in the Paradox Basin, Utah  

SciTech Connect

The primary objective of this project is to enhance domestic petroleum production by demonstration and technology transfer of an advanced oil recovery technology in the Paradox basin, southeastern Utah. If this project can demonstrate technical and economic feasibility, the technique can be applied to about 100 additional small fields in the Paradox basin alone, and result in increased recovery of 150 to 200 million barrels of oil. This project is designed to characterize five shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation and choose the best candidate for a pilot demonstration project for either a waterflood or carbon dioxide-(CO -) 2 flood project. The field demonstration, monitoring of field performance, and associated validation activities will take place in the Paradox basin within the Navajo Nation. Two activities continued this quarter as part of the geological and reservoir characterization of productive carbonate buildups in the Paradox basin: (1) diagenetic characterization of project field reservoirs, and (2) technology transfer.

David E. Eby; Thomas C. Chidsey, Jr.

1998-04-08

158

Increased Oil Production and Reserves Utilizing Secondary/Tertiary Recovery Techniques on Small Reservoirs in the Paradox Basin, Utah  

SciTech Connect

The primary objective of this project was to enhance domestic petroleum production by field demonstration and technology transfer of an advanced-oil-recovery technology in the Paradox Basin, southeastern Utah. If this project can demonstrate technical and economic feasibility, the technique can be applied to approximately 100 additional small fields in the Paradox Basin alone, and result in increased recovery of 150 to 200 million barrels (23,850,000-31,800,000 m3) of oil. This project was designed to characterize five shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation and choose the best candidate for a pilot demonstration project for either a waterflood or carbon-dioxide-(CO2-) miscible flood project. The field demonstration, monitoring of field performance, and associated validation activities will take place within the Navajo Nation, San Juan County, Utah.

Chidsey Jr., Thomas C.

2003-02-06

159

Anesthesia and liver biopsy techniques for pigeon guillemots (Cepphus columba) suspected of exposure to crude oil in marine environments  

USGS Publications Warehouse

This paper reports on the anesthesia and liver biopsy techniques used in adult and nestling pigeon guillemots (Cepphus columba) to test for continued exposure to residual crude oil in the marine environment. Populations of pigeon guillemots have declined significantly in Prince William Sound, Alaska, USA, possibly because of residual effects of crude oil in the environment after the Exxon Valdez oil spill in March 1989. Measurement of hepatic cytochrome P450 1A (CYP1A) is currently the best way to assess crude oil exposure from food sources; however, lethal sampling to obtain adequate liver tissue was not desirable in this declining population of birds. As part of a larger study to identify factors limiting the recovery of pigeon guillemots and other seabird populations, we surgically collected liver samples from adult and nestling guillemots to provide samples for measurement of hepatic CYP1A concentrations. Results from the larger study were reported elsewhere. Liver samples were taken from 26 nestling (1998) and 24 adult (1999) guillemots from a previously oiled site (Naked Island; 12 chicks, 13 adults) and from a nonoiled site (Jackpot Island/Icy Bay; 14 chicks, 11 adults). The birds were anesthetized with isoflurane. No surgical complications occurred with any of the birds and all adult and nestling birds survived after surgery to the point of release or return to the nest. Thirteen out of 14 chicks from the Jackpot Island/Icy Bay and 8 out of 12 chicks from Naked Island fledged. Four chicks at Naked Island were depredated before fledging. All adults abandoned their nests after surgery, so the study sites were revisited the following summer (2000) in an attempt to assess overwinter survival of the adults. All but 1 adult biopsied bird at the nonoiled site (Icy Bay) was found renesting, whereas only 2 birds at the previously oiled site (Naked Island) were similarly observed. The percent of 1999 breeders at Naked Island that returned to their nest sites to breed again in 2000 was low at nests of biopsied birds and nonbiopsied birds alike, suggesting that factors other than the surgical procedure were responsible for the low return rate among this group. These survival results provide strong support lot using experienced veterinarians for nonlethal invasive sample collection from birds to document exposure to crude oil in the marine environment.

Degernes, L.A.; Harms, C.A.; Golet, G.H.; Mulcahy, D.M.

2002-01-01

160

Development of acoustic agglomerator. Test plan for high temperature high pressure acoustic agglomerator  

SciTech Connect

The design specifications for the HTHP AA Facility are listed in Table 1. The facility is an open-loop, air flow system with subsystems and components to provide the high temperature, high pressure, residence time, dust loading and acoustic irradiation to simulate the aerosol and Hot Gas Cleanup (HGCU) AA system of a Pressurized Fluid Bed Combustor (PFBC), Combined Cycle Power Plant. Data sampling, instrumentation, and automatic controls and data analysis systems are also provided. This test plan describes the testing to be done on the high temperature, high pressure acoustic agglomerator (HTHP AA) at Penn State University's High Intensity Acoustic Laboratory on Department of Energy Contract No. AC21-84 MC20107.

Not Available

1985-08-12

161

Prediction techniques for materials performance in the crude oil production systems  

Microsoft Academic Search

Corrosion prediction is an important element in the planning of work over of producing oil and gas wells as well as in materials selection for new pipelines. The results of predictions may have a large economic impact on projects in the conceptual phase of design, and hence a bearing on the economic viability of the projects. Over the last few

J. Carew; S. Akashah

1994-01-01

162

Quantitative analyses of polar components in frying oils by the iatroscan thin-layer chromatography-flame ionization detection technique.  

PubMed

Frying oils collected in restaurants were fractionated into a polar and a non-polar fraction by the Iatroscan thin-layer chromatography-flame ionization detection (TLC-FID) system on Chromarod S II using hexane-diethyl ether-acetic acid (97:3:1) as the solvent system. The FID responses for Iatroscan analyses of the polar and the non-polar fraction isolated from a frying oil by column chromatography on a 5% hydrated silicic acid were studied at Chromarod load levels ranging from 1 to 16 micrograms, relative to methyl heptadecanoate as the internal standard. The correction factors were relatively constant in the range 10-16 micrograms, but increased in the range 1-5 micrograms. The amount of polar material in ten commercial frying oil samples was quantitated by the Iatroscan TLC-FID technique. Good correlations were found between the results and data obtained by column chromatography and silica gel Sep-Pak cartridges. PMID:3693474

Sébédio, J L; Astorg, P O; Septier, C; Grandgirard, A

1987-09-18

163

Oil palm fresh fruit bunch ripeness classification based on rule- based expert system of ROI image processing technique results  

NASA Astrophysics Data System (ADS)

There is a processing need for a fast, easy and accurate classification system for oil palm fruit ripeness. Such a system will be invaluable to farmers and plantation managers who need to sell their oil palm fresh fruit bunch (FFB) for the mill as this will avoid disputes. In this paper,a new approach was developed under the name of expert rules-based systembased on the image processing techniques results of thethree different oil palm FFB region of interests (ROIs), namely; ROI1 (300x300 pixels), ROI2 (50x50 pixels) and ROI3 (100x100 pixels). The results show that the best rule-based ROIs for statistical colour feature extraction with k-nearest neighbors (KNN) classifier at 94% were chosen as well as the ROIs that indicated results higher than the rule-based outcome, such as the ROIs of statistical colour feature extraction with artificial neural network (ANN) classifier at 94%, were selected for further FFB ripeness inspection system.

Alfatni, M. S. M.; Shariff, A. R. M.; Abdullah, M. Z.; Marhaban, M. H.; Shafie, S. B.; Bamiruddin, M. D.; Saaed, O. M. B.

2014-06-01

164

Change in agglomeration status and toxicokinetic fate of various nanoparticles in vivo following lung exposure in rats.  

PubMed

The deposition characteristics in lungs following inhalation, the potential toxic effects induced and the toxicokinetic fate including a possible translocation to other sites of the body are predominantly determined by the agglomeration status of nanoscaled primary particles. Systemic particle effects, i.e. effects on remote organs besides the respiratory tract are considered to be of relevant impact only for de-agglomerated particles with a nanoscaled aspect. Rats were exposed to various types of nanoscaled particles, i.e. titanium dioxide, carbon black and constantan. These were dispersed in physiologically compatible media, e.g. phosphate buffer, sometimes including auxiliaries. Rats were treated with aqueous nanoparticle dispersions by intratracheal instillation or were exposed to well-characterized nanoparticle aerosols. Subsequently, alterations in the particle size distribution were studied using transmission electron microscopy (TEM) as well as the bronchoalveolar lavage (BAL) technique. Based on the results in various approaches, a tendency of nanoscaled particles to form larger size agglomerates following deposition and interaction with cells or the respiratory tract is predominant. The contrary trend, i.e. the increase of particle number due to a disintegration of agglomerates seems not to be of high relevance. PMID:23033995

Creutzenberg, Otto; Bellmann, Bernd; Korolewitz, Regina; Koch, Wolfgang; Mangelsdorf, Inge; Tillmann, Thomas; Schaudien, Dirk

2012-10-01

165

Continuous air Agglomeration Method for high Carbon fly ash Beneficiation  

SciTech Connect

The carbon and mineral components of fly ash are effectively separated by a continuous air agglomeration method, resulting in a substantially carbon-free mineral stream and a highly concentrated carbon product. The method involves mixing the fly ash comprised of carbon and inorganic mineral matter with a liquid hydrocarbon to form a slurry, contacting the slurry with an aqueous solution, dispersing the hydrocarbon slurry into small droplets within the aqueous solution by mechanical mixing and/or aeration, concentrating the inorganic mineral matter in the aqueous solution, agglomerating the carbon and hydrocarbon in the form of droplets, collecting the droplets, separating the hydrocarbon from the concentrated carbon product, and recycling the hydrocarbon.

Gray, McMahan L.; Champagne, Kenneth J.; Finseth, Dennis H.

1998-09-29

166

Process for agglomerating particulate wood material and products obtained thereby  

SciTech Connect

The disclosure describes a process for agglomerating particulate wood material such as saw dust, wood shavings, fines, bark, tree needles, wood chips, wood dust, newspaper and cardboard material, impurities normally encountered therein and mixtures thereof. The process comprises providing a particulate wood material with a moisture content of between about 10 to 40 percent by weight calculated on a dry basis. Then, the moisture containing particulate wood material is dry mixed with dry powdered lignosulfonate to form a substantially homogeneous mixture which is compressed under a pressure of at least about 400 lbs/inch2 until the particulate wood material is agglomerated. The product obtained is resilient, easily ignitable and combustible.

Moreau, J.R.; Pelletier, M.P.; Tremblay, G.B.

1980-10-28

167

An X-ray Radiometric Technique Developed for Determining Principal Stresses in Gas and Oil Pipelines Following Shot-Blasting Treatment  

Microsoft Academic Search

An X-ray radiometric technique is proposed for determining principal stresses in oil and gas pipelines following shot-blasting treatment. Its physical essence is based on the elaboration of experimental dependences between the radioisotopic parameter and the specific volume of a crystallographic unit cell of the ? phase. The suggested technique is implemented under field conditions of pipeline routes and makes it

V. I. Bochenin; V. P. Kuznetsov; V. I. Moshkin; A. I. Neupokoev

2005-01-01

168

Innovative Techniques of Multiphase Flow in Pipeline System for Oil-Gas Gathering and Transportation with Energy-Saving and Emission-Reduction  

NASA Astrophysics Data System (ADS)

Multiphase flow measurement, desanding, dehumidification and heat furnace are critical techniques for the oil and gas gathering and transportation, which influnce intensively the energy-saving and emission-reduction in the petroleum industry. Some innovative techniques were developed for the first time by the present research team, including an online recognation instrument of multiphase flow regime, a water fraction instrument for multuphase flow, a coiled tube desanding separator with low pressure loss and high efficiency, a supersonic swirling natural gas dehumifier, and a vacuum phase-change boiler. With an integration of the above techniques, a new oil gas gathering and transpotation system was proposed, which reduced the establishment of one metering station and several transfer stations compared with the tranditional system. The oil and gas mixture transpotation in single pipes was realized. The improved techniques were applied in the oilfields in China and promoted the productivity of the oilfields by low energy consumption, low emissions, high efficiency and great security.

Bai, Bofeng; Guo, Liejin; Zhang, Shaojun; Zhang, Ximin; Gu, Hanyang

2010-03-01

169

Bird interactions with offshore oil and gas platforms: Review of impacts and monitoring techniques.  

PubMed

Thousands of oil and gas platforms are currently operating in offshore waters globally, and this industry is expected to expand in coming decades. Although the potential environmental impacts of offshore oil and gas activities are widely recognized, there is limited understanding of their impacts on migratory and resident birds. A literature review identified 24 studies and reports of bird-platform interactions, most being qualitative and half having been peer-reviewed. The most frequently observed effect, for seabirds and landbirds, is attraction and sometimes collisions associated with lights and flares; episodic events have caused the deaths of hundreds or even thousands of birds. Though typically unpredictable, anecdotally, it is known that poor weather, such as fog, precipitation and low cloud cover, can exacerbate the effect of nocturnal attraction to lights, especially when coincidental with bird migrations. Other effects include provision of foraging and roosting opportunities, increased exposure to oil and hazardous environments, increased exposure to predators, or repulsion from feeding sites. Current approaches to monitoring birds at offshore platforms have focused on observer-based methods which can offer species-level bird identification, quantify seasonal patterns of relative abundance and distribution, and document avian mortality events and underlying factors. Observer-based monitoring is time-intensive, limited in spatial and temporal coverage, and suffers without clear protocols and when not conducted by trained, independent observers. These difficulties are exacerbated because deleterious bird-platform interaction is episodic and likely requires the coincidence of multiple factors (e.g., darkness, cloud, fog, rain conditions, occurrence of birds in vicinity). Collectively, these considerations suggest a need to implement supplemental systems for monitoring bird activities around offshore platforms. Instrument-based approaches, such as radar, cameras, acoustic recordings, and telemetry, hold promise for continuous monitoring. Recommendations are provided for a rigorous and comprehensive monitoring approach within an adaptive management framework. PMID:25261750

Ronconi, Robert A; Allard, Karel A; Taylor, Philip D

2015-01-01

170

A numerical/empirical technique for history matching and predicting cyclic steam performance in Canadian oil sands reservoirs  

NASA Astrophysics Data System (ADS)

The oil sands of Alberta contain some one trillion barrels of bitumen-in-place, most contained in the McMurray, Wabiskaw, Clearwater, and Grand Rapids formations. Depth of burial is 0--550 m, 10% of which is surface mineable, the rest recoverable by in-situ technology-driven enhanced oil recovery schemes. To date, significant commercial recovery has been attributed to Cyclic Steam Stimulation (CSS) using vertical wellbores. Other techniques, such as Steam Assisted Gravity Drainage (SAGD) are proving superior to other recovery methods for increasing early oil production but at initial higher development and/or operating costs. Successful optimization of bitumen production rates from the entire reservoir is ultimately decided by the operator's understanding of the reservoir in its original state and/or the positive and negative changes which occur in oil sands and heavy oil deposits upon heat stimulation. Reservoir description is the single most important factor in attaining satisfactory history matches and forecasts for optimized production of the commercially-operated processes. Reservoir characterization which lacks understanding can destroy a project. For example, incorrect assumptions in the geological model for the Wolf Lake Project in northeast Alberta resulted in only about one-half of the predicted recovery by the original field process. It will be shown here why the presence of thin calcite streaks within oil sands can determine the success or failure of a commercial cyclic steam project. A vast amount of field data, mostly from the Primrose Heavy Oil Project (PHOP) near Cold Lake, Alberta, enabled the development a simple set of correlation curves for predicting bitumen production using CSS. A previously calibtrated thermal numerical simulation model was used in its simplist form, that is, a single layer, radial grid blocks, "fingering" or " dilation" adjusted permeability curves, and no simulated fracture, to generate the first cycle production correlation curves. The key reservoir property used to develop a specific curve was to vary the initial mobile water saturation. Individual pilot wells were then history-matched using these correlation curves, adjusting for thermal net pay using perforation height and a fundamentally derived "net pay factor". Operating days (injection plus production) were required to complete the history matching calculations. Subsequent cycles were then history-matched by applying an Efficiency Multiplication Factor (EMF) to the original first cycle prediction method as well as selecting the proper correlation curve for the specific cycle under analysis by using the appropriate steam injection rates and slug sizes. History matches were performed on eight PHOP wells (two back-to-back, five-spot patterns) completed in the Wabiskaw and, three single-well tests completed just below in the McMurray Formation. Predictions for the PHOP Wabiskaw Formation first cycle bitumen production averaged within 1% of the actual pilot total. Bitumen recovery from individual wells for second cycle onwards, was within 20% of actual values. For testing the correlations, matching was also performed on cyclic steam data from British Petroleum's Wolf Lake Project, the Esso Cold Lake Project, and the PCEJ Fort McMurray Pilot, a joint venture of Petro-Canada, Cities Services (Canadian Occidental), Esso, and Japan-Canada Oil Sands with reasonable results.

Leshchyshyn, Theodore Henry

171

Applying monitoring, verification, and accounting techniques to a real-world, enhanced oil recovery operational CO2 leak  

USGS Publications Warehouse

The use of carbon dioxide (CO2) for enhanced oil recovery (EOR) is being tested for oil fields in the Illinois Basin, USA. While this technology has shown promise for improving oil production, it has raised some issues about the safety of CO2 injection and storage. The Midwest Geological Sequestration Consortium (MGSC) organized a Monitoring, Verification, and Accounting (MVA) team to develop and deploy monitoring programs at three EOR sites in Illinois, Indiana, and Kentucky, USA. MVA goals include establishing baseline conditions to evaluate potential impacts from CO2 injection, demonstrating that project activities are protective of human health and the environment, and providing an accurate accounting of stored CO2. This paper focuses on the use of MVA techniques in monitoring a small CO2 leak from a supply line at an EOR facility under real-world conditions. The ability of shallow monitoring techniques to detect and quantify a CO2 leak under real-world conditions has been largely unproven. In July of 2009, a leak in the pipe supplying pressurized CO2 to an injection well was observed at an MGSC EOR site located in west-central Kentucky. Carbon dioxide was escaping from the supply pipe located approximately 1 m underground. The leak was discovered visually by site personnel and injection was halted immediately. At its largest extent, the hole created by the leak was approximately 1.9 m long by 1.7 m wide and 0.7 m deep in the land surface. This circumstance provided an excellent opportunity to evaluate the performance of several monitoring techniques including soil CO2 flux measurements, portable infrared gas analysis, thermal infrared imagery, and aerial hyperspectral imagery. Valuable experience was gained during this effort. Lessons learned included determining 1) hyperspectral imagery was not effective in detecting this relatively small, short-term CO2 leak, 2) even though injection was halted, the leak remained dynamic and presented a safety risk concern during monitoring activities and, 3) the atmospheric and soil monitoring techniques used were relatively cost-effective, easily and rapidly deployable, and required minimal manpower to set up and maintain for short-term assessments. However, characterization of CO2 distribution near the land surface resulting from a dynamic leak with widely variable concentrations and fluxes was challenging. ?? 2011 Published by Elsevier Ltd.

Wimmer, B.T.; Krapac, I.G.; Locke, R.; Iranmanesh, A.

2011-01-01

172

Development of a method for analysis of Iranian damask rose oil: Combination of gas chromatography–mass spectrometry with Chemometric techniques  

Microsoft Academic Search

Gas chromatography–mass spectrometry (GC–MS) combined with Chemometric resolution techniques were proposed as a method for the analysis of volatile components of Iranian damask rose oil. The essential oil of damask rose was extracted using hydrodistillation method and analyzed with GC–MS in optimized conditions. A total of 70 components were identified using similarity searches between mass spectra and MS database. This

Mehdi Jalali-Heravi; Hadi Parastar; Hassan Sereshti

2008-01-01

173

Universities' Entrepreneurial Performance: The Role of Agglomeration Economies  

ERIC Educational Resources Information Center

In spite of the extensive research on universities' entrepreneurship, whether research strength fosters or dampens their entrepreneurial performance remains controversial. Much research claims an influential role of research universities in regional economy, however, little has been said about what a part that the agglomeration economies may play…

Chen, Ping Penny

2011-01-01

174

Ignition of Flammable Atmospheres by Radiation-Heated Fibrous Agglomerates  

Microsoft Academic Search

The conditions under which laser irradiation of loose agglomerates of fine fibres or particles leads to the ignition of a surrounding flammable gas mixture are studied in relation to the hazard associated with the use of optical sensing in explosive atmospheres. Results for stoichiometric mixtures in air of a range of hydrocarbons as well as of diethyl ether, carbon disulphide

J. Adler; F. B. Carleton; F. J. Weinberg

1993-01-01

175

Engineering development of selective agglomeration. Site closeout report  

SciTech Connect

The Selective Agglomeration POC facility consisted of a coal crushing and grinding circuit, followed by an agglomeration circuit and product dewatering. (A plot plan of the facility is shown in Figure 1-2.) The coal crushing and grinding system consisted of a hammermill coal crusher, weigh-belt feeder, two ball mills (primary and secondary), and necessary hoppers, pumps, and conveyors. The mills were capable of providing coal over a range of grinds from a d{sub 50} of 125 to 25 microns. Slurry discharged from the ball mills was pumped to the agglomeration circuit. The agglomeration circuit began with a high-shear mixer, where diesel was added to the slurry to begin the formation of microagglomerates. The high-shear mixer was followed by two stages of conventional flotation cells for microagglomerate recovery. The second-stage-flotation-cell product was pumped to either a rotary-drum vacuum filter or a high-G centrifuge for dewatering. The dewatered product was then convoyed to the product pad from which dump trucks were used to transfer it to the utility plant located next to the facility. Plant tailings were pumped to the water clarifier for thickening and then dewatered in plate-and-frame filter presses. These dewatered tailings were also removed to the utility via dump truck. Clarified water (thickener overflow) was recycled to the process via a head tank.

Not Available

1993-04-01

176

Agglomeration economies and industrial location: city-level evidence  

Microsoft Academic Search

There is clear evidence that economic activity, in particular industrial activity, is unequally located in Spain. Further, the results from the analysis of single manufacturing sectors show an even higher spatial concentration. The aim of this paper is to demonstrate the extent to which agglomeration economies account for this high industrial concentration. To this end, I analyse the influence of

Elisabet Viladecans-Marsal

2004-01-01

177

Experimental study on static and impact strength of sintered agglomerates  

NASA Astrophysics Data System (ADS)

Porous internal structure is common among small bodies in the planetary systems and possible range of porosity, strength, and scale of in-homogeneity is wide. Icy agglomerates, such as icy dust aggregates in the proto-planetary disks or icy re-accumulated bodies of fragments from impact disruption beyond snow-line would have stronger bulk strength once the component particles physically connect each other due to sintering. In this study, in order to get better understanding of impact disruption process of such bodies, we first investigated the critical tensile (normal) and bending (tangential) forces to break a single neck, the connected part of the sintered particles, using sintered dimer of macro glass particles of ˜5 mm in diameter. We found that the critical tensile force is proportional to the cross-section of the neck when the neck grows sufficiently larger than the surface roughness of the original particles. We also found that smaller force is required to break a neck when the force is applied tangentially to the neck than normally applied. Then we measured the bulk tensile strength of sintered glass agglomerates consisting of 90 particles and showed that the average tensile stress to break a neck of agglomerates in static loading is consistent with the measured value for dimers. Impact experiments with velocity from 40 to 280 m/s were performed for the sintered agglomerates with ˜40% porosity, of two different bulk tensile strengths. The size ratio of the beads to the target was 0.19. The energy density required to catastrophically break the agglomerate was shown to be much less than those required for previously investigated sintered glass beads targets with ˜40% porosity, of which the size of component bead is 10 -2 times smaller and the size ratio of the bead to target is also ˜10 -2 times smaller than the agglomerates in this study. This is probably due to much smaller number of necks for the stress wave to travel through the agglomerates and therefore the energy dissipation at the necks is minimal. Also, the much larger fraction of the surface particles enables the particles to move more freely and thus be broken more easily. The catastrophic disruption of the agglomerates is shown to occur when the projectile kinetic energy is a few times of the total energy to break all of the necks of the agglomerates. The result implies that finer fragments from sintered agglomerates may have smaller catastrophic disruption energy threshold for shattering (QS?) than other larger fragments with similar porosity and bulk tensile strength but much larger number of constituent particles. If this is the case, size-dependence of QS? (smaller is weaker) is opposite to those usually considered for the bodies in the strength regime.

Machii, Nagisa; Nakamura, Akiko M.

2011-01-01

178

Phosphate-enhanced cytotoxicity of zinc oxide nanoparticles and agglomerates.  

PubMed

Zinc oxide (ZnO) nanoparticles (NPs) have been found to readily react with phosphate ions to form zinc phosphate (Zn3(PO4)2) crystallites. Because phosphates are ubiquitous in physiological fluids as well as waste water streams, it is important to examine the potential effects that the formation of Zn3(PO4)2 crystallites may have on cell viability. Thus, the cytotoxic response of NIH/3T3 fibroblast cells was assessed following 24h of exposure to ZnO NPs suspended in media with and without the standard phosphate salt supplement. Both particle dosage and size have been shown to impact the cytotoxic effects of ZnO NPs, so doses ranging from 5 to 50 ?g/mL were examined and agglomerate size effects were investigated by using the bioinert amphiphilic polymer polyvinylpyrrolidone (PVP) to generate water-soluble ZnO ranging from individually dispersed 4 nm NPs up to micron-sized agglomerates. Cell metabolic activity measures indicated that the presence of phosphate in the suspension media can led to significantly reduced cell viability at all agglomerate sizes and at lower ZnO dosages. In addition, a reduction in cell viability was observed when agglomerate size was decreased, but only in the phosphate-containing media. These metabolic activity results were reflected in separate measures of cell death via the lactate dehydrogenase assay. Our results suggest that, while higher doses of water-soluble ZnO NPs are cytotoxic, the presence of phosphates in the surrounding fluid can lead to significantly elevated levels of cell death at lower ZnO NP doses. Moreover, the extent of this death can potentially be modulated or offset by tuning the agglomerate size. These findings underscore the importance of understanding how nanoscale materials can interact with the components of surrounding fluids so that potential adverse effects of such interactions can be controlled. PMID:24362007

Everett, W Neil; Chern, Christina; Sun, Dazhi; McMahon, Rebecca E; Zhang, Xi; Chen, Wei-Jung A; Hahn, Mariah S; Sue, H-J

2014-02-10

179

Investigation and technique in the fluorescent spectra examination of crude oil  

E-print Network

+ e 0 Ol tr 0 0 N 0 O e t5 crt 0 n 0 fc '0 0 n k O V' V ff' 3000 Aono gOI O 6ono Ic'avelength in A. I:. pete rmination (1) 3800 A. U. & Figure 5 of Optimum Concentration at (2) 4000 A V & and (3) 4300 A. U, 15 I I C& C... Crude Oil Bed Depth: 67. 0 cm. Total 1"t. of Fluores- Frac- Devel- Vol. wt. of insol. Color of Solution Color of Residue cent o Inten- ti t r 1. R 'd B. t ' 1 1 1 tt . V. 1 1 tt 1 U. V. B A~A't 1H1 1H2 101 102 1 B 1 1 B 2 1BQ lE1 1F1 H 600...

Chambers, Gilbert Vester

2012-06-07

180

The Physics of Protoplanetesimal Dust Agglomerates. V. Multiple Impacts of Dusty Agglomerates at Velocities Above the Fragmentation Threshold  

Microsoft Academic Search

In recent years, a number of new experiments have advanced our knowledge on the early growth phases of protoplanetary dust aggregates. Some of these experiments have shown that collisions between porous and compacted agglomerates at velocities above the fragmentation threshold velocity can lead to growth of the compact body, when the porous collision partner fragments upon impact and transfers mass

Stefan Kothe; Carsten Guettler; Juergen Blum

2010-01-01

181

The preparation of agglomerates containing solid dispersions of diazepam by melt agglomeration in a high shear mixer.  

PubMed

The aim of this study was to prepare by melt agglomeration agglomerates containing solid dispersions of diazepam as poorly water-soluble model drug in order to evaluate the possibility of improving the dissolution rate. Lactose monohydrate was melt agglomerated with polyethylene glycol (PEG) 3000 or Gelucire 50/13 (mixture of glycerides and PEG esters of fatty acids) as meltable binders in a high shear mixer. The binders were added either as a mixture of melted binder and diazepam by a pump-on procedure or by a melt-in procedure of solid binder particles. Different drug concentrations, maximum manufacturing temperatures, and cooling rates were investigated. It was found to be possible to increase the dissolution rate of diazepam by melt agglomeration. A higher dissolution rate was obtained with a lower drug concentration. Admixing the binders by the melt-in procedure resulted in similar dissolution rates as the pump-on procedure. The different maximum manufacturing temperatures and cooling rates were found to have complex effects on the dissolution rate for formulations containing PEG 3000, whereas only minor effects of the cooling procedure were found with Gelucire 50/13. Gelucire 50/13 resulted in faster dissolution rates compared to PEG 3000. PMID:12787644

Seo, Anette; Holm, Per; Kristensen, Henning Gjelstrup; Schaefer, Torben

2003-06-18

182

Numerical modelling of the breakage of loose agglomerates of fine particles Z.B. Tong a  

E-print Network

before disintegrating into small fragments. The velocity field of the agglomerates showed a clear shear) are weakly formed in order to have easy dispersion when in use [13]. Comparing with hard agglomerates, loose agglomerates are expected to behave quite differently on impact and often disintegrate into many small pieces

Frey, Pascal

183

Using Essential Oils to Teach Advanced-Level Organic Chemistry Separation Techniques and Spectroscopy  

ERIC Educational Resources Information Center

Students sometimes have difficulty grasping the importance of when and how basic distillation techniques, column chromatography, TLC, and basic spectroscopy (IR and NMR) can be used to identify unknown compounds within a mixture. This two-part experiment uses mixtures of pleasant-smelling, readily available terpenoid compounds as unknowns to…

Bott, Tina M.; Wan, Hayley

2013-01-01

184

Recovering Bioactive Compounds from Olive Oil Filter Cake by Advanced Extraction Techniques  

PubMed Central

The potential of by-products generated during extra-virgin olive oil (EVOO) filtration as a natural source of phenolic compounds (with demonstrated bioactivity) has been evaluated using pressurized liquid extraction (PLE) and considering mixtures of two GRAS (generally recognized as safe) solvents (ethanol and water) at temperatures ranging from 40 to 175 °C. The extracts were characterized by high-performance liquid chromatography (HPLC) coupled to diode array detection (DAD) and electrospray time-of-flight mass spectrometry (HPLC-DAD-ESI-TOF/MS) to determine the phenolic-composition of the filter cake. The best isolation procedure to extract the phenolic fraction from the filter cake was accomplished using ethanol and water (50:50, v/v) at 120 °C. The main phenolic compounds identified in the samples were characterized as phenolic alcohols or derivatives (hydroxytyrosol and its oxidation product), secoiridoids (decarboxymethylated and hydroxylated forms of oleuropein and ligstroside aglycones), flavones (luteolin and apigenin) and elenolic acid derivatives. The PLE extraction process can be applied to produce enriched extracts with applications as bioactive food ingredients, as well as nutraceuticals. PMID:25226536

Lozano-Sánchez, Jesús; Castro-Puyana, María; Mendiola, Jose A.; Segura-Carretero, Antonio; Cifuentes, Alejandro; Ibáñez, Elena

2014-01-01

185

Development of Impregnated Agglomerate Pelletization (IAP) process for fabrication of (Th,U)O 2 mixed oxide pellets  

NASA Astrophysics Data System (ADS)

Impregnated Agglomerate Pelletization (IAP) technique has been developed at Advanced Fuel Fabrication Facility (AFFF), BARC, Tarapur, for manufacturing (Th, 233U)O 2 mixed oxide fuel pellets, which are remotely fabricated in hot cell or shielded glove box facilities to reduce man-rem problem associated with 232U daughter radionuclides. This technique is being investigated to fabricate the fuel for Indian Advanced Heavy Water Reactor (AHWR). In the IAP process, ThO 2 is converted to free flowing spheroids by powder extrusion route in an unshielded facility which are then coated with uranyl nitrate solution in a shielded facility. The dried coated agglomerate is finally compacted and then sintered in oxidizing/reducing atmosphere to obtain high density (Th,U)O 2 pellets. In this study, fabrication of (Th,U)O 2 mixed oxide pellets containing 3-5 wt.% UO 2 was carried out by IAP process. The pellets obtained were characterized using optical microscopy, XRD and alpha autoradiography. The results obtained were compared with the results for the pellets fabricated by other routes such as Coated Agglomerate Pelletization (CAP) and Powder Oxide Pelletization (POP) route.

Khot, P. M.; Nehete, Y. G.; Fulzele, A. K.; Baghra, Chetan; Mishra, A. K.; Afzal, Mohd.; Panakkal, J. P.; Kamath, H. S.

2012-01-01

186

Soot oxidation and agglomeration modeling in a microgravity diffusion flame  

SciTech Connect

The global evolution of a microgravity diffusion flame is detailed. Gas species evolution is computed using a reduced finite rate chemical mechanism. Soot evolution is computed using various combinations of existing soot mechanisms. Radiative transfer is coupled to the soot and gas phase chemistry processes using a P1 spherical harmonics radiation model. The soot agglomeration model was examined to note the dependence of soot growth and oxidation processes on soot surface area predictions. For limiting cases where agglomeration was excluded from the soot evolution model, soot primary particle sizes and number concentrations were calculated, and the number of primary particles per aggregate was inferred. These computations are compared with experimental results for microgravity and nonbuoyant flame conditions.

Ezekoye, O.A.; Zhang, Z. [Univ. of Texas, Austin, TX (United States). Dept. of Mechanical Engineering] [Univ. of Texas, Austin, TX (United States). Dept. of Mechanical Engineering

1997-07-01

187

On Some Versions of the Element Agglomeration AMGe Method  

SciTech Connect

The present paper deals with element-based AMG methods that target linear systems of equations coming from finite element discretizations of elliptic PDEs. The individual element information (element matrices and element topology) is the main input to construct the AMG hierarchy. We study a number of variants of the spectral agglomerate element based AMG method. The core of the algorithms relies on element agglomeration utilizing the element topology (built recursively from fine to coarse levels). The actual selection of the coarse degrees of freedom (dofs) is based on solving large number of local eigenvalue problems. Additionally, we investigate strategies for adaptive AMG as well as multigrid cycles that are more expensive than the V-cycle utilizing simple interpolation matrices and nested conjugate gradient (CG) based recursive calls between the levels. The presented algorithms are illustrated with an extensive set of experiments based on a matlab implementation of the methods.

Lashuk, I; Vassilevski, P

2007-08-09

188

Engineering development of selective agglomeration: Trace element removal study  

SciTech Connect

Southern Company Services, Inc., (SCS) was contracted in 1989 by the US Department of Energy (DOE) to develop a commercially acceptable selective agglomeration technology to enhance the use of high-sulfur coals by 1993. The project scope involved development of a bench-scale process and components, as well as the design, testing, and evaluation of a proof-of-concept (POC) facility. To that end, a two-ton-per-hour facility was constructed and tested near Wilsonville, Alabama. Although it was not the primary focus of the test program, SCS also measured the ability of selective agglomeration to remove trace elements from coal. This document describes the results of that program.

Not Available

1993-09-01

189

Predicting oil quality from sidewall cores using PFID, TEC, and NIR analytical techniques in sandstone reservoirs, Offshore Cameroon  

Microsoft Academic Search

Cameroon reservoirs contain oil and gas that have migrated vertically from deeper buried thermally mature marine shales. Several shallow reservoirs also contain biogenic gas. Generally, lower gravity oils found in the shallow reservoirs have undergone various degrees of biodegradation. Deeper accumulations are higher gravity {open_quote}primary{close_quote} oils. The biodegraded oils are characterized by lower gravities, higher acid numbers, higher sulfur contents,

W. O. Bement; R. I. McNeil; R. G. Lippincott

1996-01-01

190

AGGLOMERATION BEHAVIOR IN A BUBBLING FLUIDIZED BED AT HIGH TEMPERATURE  

Microsoft Academic Search

Minimum fluidization velocity and agglomeration behavior were investigated at high temperature in an 80?×?30?mm two-dimensional quartz fluidized bed and in an 82?mm i.d. circular fluidized bed. Bed materials tested were two sizes of glass beads as well as three sizes of fluidized bed combustor (FBC) ash. The minimum fluidization velocity decreased with increasing bed temperature, whereas the minimum sintering fluidization

QINGJIE GUO; TOSHIYUKI SUDA; Juni'Chi Sato; GUANGXI YUE

2004-01-01

191

Suppression of cobalt silicide agglomeration using nitrogen (N2+) implantation  

Microsoft Academic Search

In this paper, the effects of nitrogen coimplantation with boron into p+-poly gate in PMOSFETs on the agglomeration effects of CoSi2 are studied. The thermal stability of CoSi2\\/poly-Si stacked layers can be significantly improved by using nitrogen implantation. Samples with 40-nm cobalt silicide (CoSi 2) on 210-nm poly-Si implanted by 2×1015\\/cm 2 N2+ are thermally stable above 950°C for 30

Wein-Town Sun; Ming-Chi Liaw; C. C.-H. Hsu

1998-01-01

192

The optimization of essential oils supercritical CO2 extraction from Lavandula hybrida through static-dynamic steps procedure and semi-continuous technique using response surface method  

PubMed Central

Aim: The aim of this study was to examine and evaluate crucial variables in essential oils extraction process from Lavandula hybrida through static-dynamic and semi-continuous techniques using response surface method. Materials and Methods: Essential oil components were extracted from Lavandula hybrida (Lavandin) flowers using supercritical carbon dioxide via static-dynamic steps (SDS) procedure, and semi-continuous (SC) technique. Results: Using response surface method the optimum extraction yield (4.768%) was obtained via SDS at 108.7 bar, 48.5°C, 120 min (static: 8×15), 24 min (dynamic: 8×3 min) in contrast to the 4.620% extraction yield for the SC at 111.6 bar, 49.2°C, 14 min (static), 121.1 min (dynamic). Conclusion: The results indicated that a substantial reduction (81.56%) solvent usage (kg CO2/g oil) is observed in the SDS method versus the conventional SC method. PMID:25598636

Kamali, Hossein; Aminimoghadamfarouj, Noushin; Golmakani, Ebrahim; Nematollahi, Alireza

2015-01-01

193

Application of data mining techniques to identify data anomalies: a case study in the oil and gas industry  

NASA Astrophysics Data System (ADS)

This paper presents the application of the AgentMinerTM tool suite to improve the efficiency of detecting data anomalies in oil well log and production data sets, which have traditionally been done by hand or through the use of database business rules. There was a need to verify the data sets, once cleansed and certified to ensure that the existing data certification process was effective. There was also a need to identify more complex relational data anomalies that cannot be addressed by simple business rules. Analysis techniques including statistical clustering, correlation and 3-D data visualization techniques were successfully utilized to identify potential complex data anomalies. A data-preprocessing tool was also applied to automatically detect simple data errors such as missing, out of range, and null values. The pre-processing tools were also used to prepare the data sets for further statistical and visualization analyses. To enhance the discovery of data anomalies two different data visualization tools for the data clusters were applied.

McCormack, Jenifer S.; Wohlschlaeger, Brian; Lanier, Bryan

2002-03-01

194

Turbulent hydrodynamic stress induced dispersion and fragmentation of nanoscale agglomerates.  

PubMed

High pressure dispersion nozzles of 2.5-10 mm length and 125 microm diameter have been characterized in terms of fluid dynamics and dispersion experiments at 100-1400 bar. Elongational stresses at the nozzle entry (5 x 10(5) Pa) and turbulent stresses up to 10(5) Pa at a Reynolds number of 25,000 in turbulent channel flow are identified crucial for desagglomeration and aggregate fragmentation. Maximum stresses are calculated on representative particle tracks and related to agglomerate breakage. Agglomerates in the experimental study are in the range of the Kolmogorov micro scale (100-400 nm) and therefore break due to turbulent energy dissipation in viscous flow. Bond strength distributions could be determined experimentally from particle size distributions and fluid dynamics simulations, with primary particle erosion determined as dispersion mechanism for diffusion flame silica particles. Nanoscale agglomerates show a power law scaling for breakage with scaling exponents diverging from theory of floc dispersion. This is attributed to their strong bonding by sinter necks. PMID:17109876

Wengeler, R; Nirschl, H

2007-02-15

195

On the mechanisms of formation of spherical agglomerates.  

PubMed

Spherical agglomerates of benzoic acid have been successfully prepared by semi-batch, agitated vessel, drowning-out crystallization in water-ethanol-toluene mixtures. Benzoic acid is dissolved in ethanol, toluene is added and this mixture is fed at constant rate to the agitated crystallizer containing water. The influence of the amount of bridging liquid and the feeding rate on the product particle size distribution, morphology, and mechanical compression characteristics have been investigated. Compression characteristics for single agglomerates are compared with data on bed compression. With increasing amount of bridging liquid the particle size and strength increases and morphology improves. Particle size decreases and the fracture force increases with increasing feeding rate but the morphology remains unchanged. Using toluene as opposed to chloroform as the bridging liquid leads to improved product properties. Experiments have also been performed to reveal the mechanisms of the formation of the agglomerates. The results show that along the course of the process the properties of the particles change gradually but substantially. Particle size and number increases along with increasing feed. The spherical shape does not appear immediately but develops gradually, and is shown to be very much the result of the agitation of the slurry. PMID:21216285

Thati, Jyothi; Rasmuson, Ake C

2011-03-18

196

Productivity and quality of volatile oil extracted from Mentha spicata and M. arvensis var. piperascens grown by a hydroponic system using the deep flow technique  

Microsoft Academic Search

The purpose of this study was to determine the differences between spearmint (Mentha spicata L.) and Japanese mint (M. arvensis L. var. piperascens Malinv.) cultivated in either soil or nutrient solution using the deep flow technique (DFT). The differences were measured\\u000a in terms of harvest period (full bloom period) and quantity and chemical components of volatile oils. The spearmint and

Sornkanok Vimolmangkang; Worapan Sitthithaworn; Danai Vannavanich; Sunisa Keattikunpairoj; Chuda Chittasupho

2010-01-01

197

Synthesis of glycylglycine-imprinted silica microspheres through different water-in-oil emulsion techniques.  

PubMed

Sol-gel molecularly imprinted materials (MIMs) are traditionally obtained by grinding and sieving of a monolith formed by bulk polymerization. However, this process has several drawbacks that can be overcome if these materials are synthesized directly in the spherical format. This work aimed at the development of two efficient methods to prepare spherical glycylglycine-templated silica ("whole-imprinted" and surface-imprinted) through a combination of sol-gel and emulsion techniques. The synthesis of the microspheres was optimized regarding emulsion and sol-gel parameters. Imprinting efficiency of the prepared materials was studied by solid phase extraction and flow microcalorimetry. The particles prepared with glycylglycine and functional monomer, in basic medium (using cyclohexane as non-polar continuous medium) presented the highest imprinting factor - 2.5 - and the respective surface-imprinted material presented an imprinting factor of 1.5. The results of flow microcalorimetry confirmed the action of different mechanisms of glycylglycine adsorption: entropically-controlled interactions were present for the "whole-imprinted" material, indicating adsorption inside small imprinted pores; enthalpically-controlled interactions were observed for the surface-imprinted material, a behaviour more compatible with a template/surface-only interaction. Globally, the two approaches allowed for a successful imprinting effect which was more extensive for the "whole-imprinted" material, whereas the surface-imprinting feature confers to the surface-imprinted xerogel advantages regarding mass transfer kinetics. Overall, the spherical particles obtained by both approaches presented characteristics, such as sphericity, mesoporosity, easy/fast accessibility to imprinted sites, important indicators that these materials may be candidates for stationary phases for efficient, selective chromatographic separation. PMID:23706547

Ornelas, Mariana; Loureiro, Dianne; Araújo, Maria João; Marques, Eduardo; Dias-Cabral, Cristina; Azenha, Manuel; Silva, Fernando

2013-07-01

198

The role of nitrogen and sulphur bearing compounds in the wettability of oil reservoir rocks: an approach with nuclear microanalysis and other related surface techniques  

NASA Astrophysics Data System (ADS)

Oil recovery is strongly influenced by the wettability of the reservoir rock. Some constituents of the crude oil (polar compounds and heavy fractions such as asphaltenes with heteroatoms) are believed to react with the reservoir rock and to condition the local wettability. Therefore, it is important to obtain as much knowledge as possible about the characteristics of the organic matter/mineral interactions. This study is devoted to the description at the microscopic scale of the distribution of some heavy fractions of crude oil (asphaltenes) and nitrogen molecules (pyridine and pyrrole) on model minerals of sandstone reservoir rocks such as silica and clays. Nuclear microanalysis, X-Ray Photoelectron Spectroscopy and other related microscopic imaging techniques allow to study the distribution and thickness of the organic films. The respective influences of the nature of the mineral substrate and the organic matter are studied. The important role played by the nitrogen compounds in the adsorption of organic matter is emphasized.

Mercier, F.; Toulhoat, N.; Potocek, V.; Trocellier, P.

1999-04-01

199

Investigation of the radiative properties of chain agglomerated soot formed in hydrocarbon diffusion flames  

Microsoft Academic Search

An investigation into the radiative scattering and extinction properties of chain-agglomerated soot particles, formed in hydrocarbon diffusion flames, has been conducted. Several different theoretical approximations of the agglomerate radiative behavior were examined. Based upon these approximations, the radiative properties of chain-agglomerates can show significant departure from those produced by spherically-shaped particles. For the visible and infrared wavelengths, a significant difference

Mackowski

1987-01-01

200

Productivity and quality of volatile oil extracted from Mentha spicata and M. arvensis var. piperascens grown by a hydroponic system using the deep flow technique.  

PubMed

The purpose of this study was to determine the differences between spearmint (Mentha spicata L.) and Japanese mint (M. arvensis L. var. piperascens Malinv.) cultivated in either soil or nutrient solution using the deep flow technique (DFT). The differences were measured in terms of harvest period (full bloom period) and quantity and chemical components of volatile oils. The spearmint and Japanese mint were cultivated in four different nutrient formulas: plant standard nutrient, plant standard nutrient with an amino acid mixture, plant standard nutrient with a sulphur compound, and a combination of plant standard nutrient with an amino acid mixture and a sulphur compound. We observed that cultivation of spearmint and Japanese mint in nutrient solution using DFT is an effective method to provide high production of volatile oil, since it results in an earlier harvest period and higher quantity of volatile oil. We determined that for spearmint an amino acid mixture is an appropriate nutrient supplement to enhance production of volatile oil with optimum carvone content. Finally, we observed high menthol content in Japanese mint grown in all four nutrient formulas; however, supplementation with a combination of sulphur fertilisation and amino acid mixture yields the highest quantity of volatile oil. PMID:19763744

Vimolmangkang, Sornkanok; Sitthithaworn, Worapan; Vannavanich, Danai; Keattikunpairoj, Sunisa; Chittasupho, Chuda

2010-01-01

201

Asymmetry in retail gasoline and crude oil price movements in the United States: An application of hidden cointegration technique  

Microsoft Academic Search

There is a common belief that gasoline prices respond more quickly to crude oil price increases than decreases. Some economists and politicians believe that asymmetry in oil and gasoline price movements is the outcome of a non-competitive gasoline market requiring that governments take policy action to address “unfair pricing”. There is no consensus as to the existence, or nature, of

Afshin Honarvar

2009-01-01

202

Assessment of infrared spectroscopy and multivariate techniques for monitoring the service condition of diesel-engine lubricating oils  

Microsoft Academic Search

This paper presents two methodologies for monitoring the service condition of diesel-engine lubricating oils on the basis of infrared spectra. In the first approach, oils samples are discriminated into three groups, each one associated to a given wear stage. An algorithm is proposed to select spectral variables with good discriminant power and small collinearity for the purpose of discriminant analysis

Arnobio Roberto Caneca; M. Fernanda Pimentel; Roberto Kawakami Harrop Galvão; Cláudia Eliane da Matta; Florival Rodrigues de Carvalho; Ivo M. Raimundo Jr.; Celio Pasquini; Jarbas J. R. Rohwedder

2006-01-01

203

Effect of morphology on light scattering by agglomerates  

NASA Astrophysics Data System (ADS)

Using the discrete dipole approximation (DDA), we compute light scattering from irregularly shaped particles with three different types of agglomerate morphologies. The packing density of materials in the model particles spans the range from 0.169 through 0.336. We investigate four different refractive indices m=1.313+0i, 1.6+0.0005i, 1.5+0.1i, and 1.855+0.45i, which are representative of various cosmic and terrestrial materials in the visible. In each case, we consider a wide range of size parameters that makes it possible to average the light-scattering response over particle size with a power-law size distribution. We find that despite noticeable differences in particle morphology, their light-scattering responses are remarkably similar; the difference in light scattering often does not exceed the error bars occurring in laboratory measurements of micron-sized particles. On the contrary, the impact of refractive index and size distribution on light scattering appears to be much stronger compared with the morphology of complex, agglomerate particles. This finding may simplify considerably the interpretation of photo-polarimetric observations of atmospheric aerosols, cosmic dust particles, etc., because the precise specification of target-particle shape is unnecessary for the analysis.

Zubko, Evgenij; Shkuratov, Yuriy; Videen, Gorden

2015-01-01

204

Agglomeration of soot particles in diffusion flames under microgravity  

SciTech Connect

Experiments have been conducted to investigate the behavior of soot particles in diffusion flames under microgravity conditions using a 490-m drop shaft (10-s microgravity duration) in Hokkaido, Japan. Flames from the combustion of paper sheets and butane jet diffusion flames are observed under microgravity. The oxygen concentration of the surroundings, the butane flow rate,and the burner diameter are varied as experimental parameters. The generated soot particles are sampled under microgravity and observed using scanning electron and transmission electron microscopes. The flames with a residual convection or forced convection are also observed to examine the influence of flow field on soot particle generation under microgravity. From these results, it is found that a number of large luminous spots appear in diffusion flames under microgravity. From the observation of TEM images, the luminous spots are the result of agglomerated soot particles and the growth of their diameters to a discernible level. The diameter of the agglomerated particles measure about 0.1 mm, 200 to 500 times as large as those generated under normal gravity. It is suggested that these large soot particles are generated in the limited areas where the conditions for the formation of these particles, such as gas velocity (residence time) and oxygen concentration, are satisfied.

Ito, H.; Fujita, O.; Ito, K.

1994-11-01

205

Transport, mixing and agglomeration of particles in turbulent flows  

NASA Astrophysics Data System (ADS)

This paper describes methods and approaches that have been used to simulate and model the transport, mixing and agglomeration of small particles in a flowing turbulent gas. The transported particles because of their inertia are assumed not to follow the motion of the large scales of the turbulence and or the motion of the small dissipating scales of the turbulence. We show how both these behaviours can be represented by a PDF approach analogous to that used in Classical Kinetic Theory. For large scale dispersion the focus is on transport in simple generic flows like statistically stationary homogeneous and isotropic turbulence and simple shear flows. Special consideration is given to the transport and deposition of particles in turbulent boundary layers. For small scale transport the focus is on how the the small scales of turbulence together with the particle inertial response enhances collision processes like particle agglomeration. In this case the importance of segregation and the formation of caustics, singularities and random uncorrelated motion is highlighted and discussed.

Reeks, Michael W.

2014-08-01

206

Investigations on a Novel Inductive Concept Frequency Technique for the Grading of Oil Palm Fresh Fruit Bunches  

PubMed Central

From the Malaysian harvester's perspective, the determination of the ripeness of the oil palm (FFB) is a critical factor to maximize palm oil production. A preliminary study of a novel oil palm fruit sensor to detect the maturity of oil palm fruit bunches is presented. To optimize the functionality of the sensor, the frequency characteristics of air coils of various diameters are investigated to determine their inductance and resonant characteristics. Sixteen samples from two categories, namely ripe oil palm fruitlets and unripe oil palm fruitlets, are tested from 100 Hz up to 100 MHz frequency. The results showed the inductance and resonant characteristics of the air coil sensors display significant changes among the samples of each category. The investigations on the frequency characteristics of the sensor air coils are studied to observe the effect of variations in the coil diameter. The effect of coil diameter yields a significant 0.02643 MHz difference between unripe samples to air and 0.01084 MHz for ripe samples to air. The designed sensor exhibits significant potential in determining the maturity of oil palm fruits. PMID:23435051

Harun, Noor Hasmiza; Misron, Norhisam; Sidek, Roslina Mohd; Aris, Ishak; Ahmad, Desa; Wakiwaka, Hiroyuki; Tashiro, Kunihisa

2013-01-01

207

SIMPLE TECHNIQUES FOR ASSESSING IMPACTS OF OIL AND GAS OPERATIONS ON PUBLIC LANDS- USE OF A PHOTOIONIZATION DETECTOR TO EVALUATE HYDROCARBONS IN THE SUBSURFACE  

Microsoft Academic Search

Simple, cost-effective techniques are needed for land managers to assess the environmental impacts of oil and gas production activities on public lands, so that sites may be prioritized for remediation or for further, more formal assessment. Field-portable instruments provide real-time data and allow the field investigator to extend an assessment beyond simply locating and mapping obvious impacts. Field investigators can

James K. Otton; Robert A. Zielinski

208

A 3D agglomeration multigrid solver for the Reynolds-averaged Navier-Stokes equations on unstructured meshes  

NASA Technical Reports Server (NTRS)

An agglomeration multigrid strategy is developed and implemented for the solution of three-dimensional steady viscous flows. The method enables convergence acceleration with minimal additional memory overheads, and is completely automated, in that it can deal with grids of arbitrary construction. The multigrid technique is validated by comparing the delivered convergence rates with those obtained by a previously developed overset-mesh multigrid approach, and by demonstrating grid independent convergence rates for aerodynamic problems on very large grids. Prospects for further increases in multigrid efficiency for high-Reynolds number viscous flows on highly stretched meshes are discussed.

Marvriplis, D. J.; Venkatakrishnan, V.

1995-01-01

209

Industrial Agglomeration, Geographic Innovation and Total Factor Productivity: The Case of Taiwan  

E-print Network

Industrial Agglomeration, Geographic Innovation and Total Factor Productivity: The Case of Taiwan by Chia-Lin Chang and Les Oxley No: 14/2008 #12;2 WORKING PAPER No. 14/2008 Industrial Agglomeration, R 242 four-digit standard industrial classification (SIC) industries in Taiwan in 2001, we compute TFP

Hickman, Mark

210

Propellant Formulation Factors and Metal Agglomeration in Combustion of Aluminized Solid Rocket Propellant  

Microsoft Academic Search

An experimental study of aluminized solid rocket propellant combustion was conducted in order to determine the influence of various propellant formulation factors on metal agglomeration. The results allowed us to determine the dependencies of the agglomeration process characteristics on the physical and mechanical properties of the propellant binder, the particle size of the metal fuel, the type of film covering

V. A. BABUK; V. A. VASSILIEV; V. V. SVIRIDOV

2001-01-01

211

DYNAMIC BEHAVIOR OF PARTICLE AGGLOMERATION OF EUROPIUM OXALATE DURING REACTION CRYSTALLIZATION IN SEMI-BATCH REACTOR  

Microsoft Academic Search

During reaction crystallization of europium oxalate in a semi-batch reactor, a monotonical increase in the mean particle size and corresponding reduction in the total particle population were observed due to particle agglomeration occurring simultaneously with particle nucleation and growth. However, since particle agglomeration was achieved via particle aggregation and molecular growth, the mean particle size and total particle population in

Woo-Sik Kim; Woon-Soo Kim; Kwang-Seok Kim; Joon-Soo Kim; Taesung Jung; Michael D. Ward

2006-01-01

212

A model for transport and agglomeration of particles in reactive ion etching plasma reactors  

E-print Network

that the rate and extent of particle agglomeration depend on the particle density, plasma power deposition, andA model for transport and agglomeration of particles in reactive ion etching plasma reactors Fred Y particle contamination of wafers in reactive ion etching RIE plasma tools is a continuing concern

Kushner, Mark

213

Application of acoustic agglomerators for emergency use in liquid-metal fast breeder reactor plants  

Microsoft Academic Search

The use of acoustic agglomerators for the suppression of sodium-fire aerosols in the case of a hypothetical core disruptive accident of a liquid-metal fast breeder reactor is discussed. The basic principle for the enhancement of agglomeration of airborne particles under the influence of an acoustic field is first discussed, followed by theoretical predictions of the optimum operating conditions for such

D. T. Shaw; N. Rajendran

1979-01-01

214

DEFORESTATION, GROWTH AND AGGLOMERATION EFFECTS: EVIDENCE FROM AGRICULTURE IN THE BRAZILIAN AMAZON  

Microsoft Academic Search

The role of population growth and migration has been emphasized as a key variable to explain deforestation and land conversion in developing countries. The spatial distribution of human population and economic activities is remarkably uneven. At any geographical scale we find that different forms of agglomerations are pervasive. On the one hand, in central countries or regions, agglomeration is reflected

Danilo Camargo Igliori

2006-01-01

215

Influence of primary-particle density in the morphology of agglomerates.  

PubMed

Agglomeration processes occur in many different realms of science, such as colloid and aerosol formation or formation of bacterial colonies. We study the influence of primary-particle density in agglomerate structures using diffusion-controlled Monte Carlo simulations with realistic space scales through different regimes (diffusion-limited aggregation and diffusion-limited colloid aggregation). The equivalence of Monte Carlo time steps to real time scales is given by Hirsch's hydrodynamical theory of Brownian motion. Agglomerate behavior at different time stages of the simulations suggests that three indices (the fractal exponent, the coordination number, and the eccentricity index) characterize agglomerate geometry. Using these indices, we have found that the initial density of primary particles greatly influences the final structure of the agglomerate, as observed in recent experimental works. PMID:25122302

Camejo, M D; Espeso, D R; Bonilla, L L

2014-07-01

216

Analysis of river pollution data from low-flow period by means of multivariate techniques: a case study from the oil-shale industry region, northeastern Estonia.  

PubMed

The oil-shale industry has created serious pollution problems in northeastern Estonia. Untreated, phenol-rich leachate from semi-coke mounds formed as a by-product of oil-shale processing is discharged into the Baltic Sea via channels and rivers. An exploratory analysis of water chemical and microbiological data sets from the low-flow period was carried out using different multivariate analysis techniques. Principal component analysis allowed us to distinguish different locations in the river system. The riverine microbial community response to water chemical parameters was assessed by co-inertia analysis. Water pH, COD and total nitrogen were negatively related to the number of biodegradative bacteria, while oxygen concentration promoted the abundance of these bacteria. The results demonstrate the utility of multivariate statistical techniques as tools for estimating the magnitude and extent of pollution based on river water chemical and microbiological parameters. An evaluation of river chemical and microbiological data suggests that the ambient natural attenuation mechanisms only partly eliminate pollutants from river water, and that a sufficient reduction of more recalcitrant compounds could be achieved through the reduction of wastewater discharge from the oil-shale chemical industry into the rivers. PMID:12638742

Truu, Jaak; Heinaru, Eeva; Talpsep, Ene; Heinaru, Ain

2002-01-01

217

Coagulation-Agglomeration of Fractal-like Particles: Structure and Self-Preserving Size Distribution.  

PubMed

Agglomeration occurs in environmental and industrial processes, especially at low temperatures where particle sintering or coalescence is rather slow. Here, the growth and structure of particles undergoing agglomeration (coagulation in the absence of coalescence, condensation, or surface growth) are investigated from the free molecular to the continuum regime by discrete element modeling (DEM). Particles coagulating in the free molecular regime follow ballistic trajectories described by an event-driven method, whereas in the near-continuum (gas-slip) and continuum regimes, Langevin dynamics describe their diffusive motion. Agglomerates containing about 10-30 primary particles, on the average, attain their asymptotic fractal dimension, Df, of 1.91 or 1.78 by ballistic or diffusion-limited cluster-cluster agglomeration, corresponding to coagulation in the free molecular or continuum regimes, respectively. A correlation is proposed for the asymptotic evolution of agglomerate Df as a function of the average number of constituent primary particles, n?p. Agglomerates exhibit considerably broader self-preserving size distribution (SPSD) by coagulation than spherical particles: the number-based geometric standard deviations of the SPSD agglomerate radius of gyration in the free molecular and continuum regimes are 2.27 and 1.95, respectively, compared to ?1.45 for spheres. In the transition regime, agglomerates exhibit a quasi-SPSD whose geometric standard deviation passes through a minimum at Knudsen number Kn ? 0.2. In contrast, the asymptotic Df shifts linearly from 1.91 in the free molecular regime to 1.78 in the continuum regime. Population balance models using the radius of gyration as collision radius underestimate (up to about 80%) the small tail of the SPSD and slightly overpredict the overall agglomerate coagulation rate, as they do not account for cluster interpenetration during coagulation. In the continuum regime, when a recently developed agglomeration rate is used in population balance equations, the resulting SPSD is in excellent agreement with that obtained by DEM. PMID:25560979

Goudeli, Eirini; Eggersdorfer, Maximilian L; Pratsinis, Sotiris E

2015-02-01

218

Engine bearing oil film thickness measurement and oil rheologh  

Microsoft Academic Search

An American Society for Testing and Materials (ASTM) Task Force was formed in 1984 to: (1) establish a series of reference oils, (2) measure the minimum bearing oil film thicknesses provided by the oils in fired engine, and (3) interpret the results in terms of oil rheological properties. Minimum oil film thickness (MOFT) measurement and analysis techniques using a capacitance

S. A. Cryvoff; J. A. Spearot; T. W. Bates

1990-01-01

219

Ligand-dominated temperature dependence of agglomeration kinetics and morphology in alkyl-thiol-coated gold nanoparticles  

NASA Astrophysics Data System (ADS)

The stability of nanoparticle suspensions and the details of their agglomeration depend on the interactions between particles. We study this relationship in gold nanoparticles stabilized with different alkyl thiols in heptane. Temperature-dependent interactions were inferred from small-angle x-ray scattering, agglomeration kinetics from dynamic light scattering, and agglomerate morphologies from transmission electron microscopy. We find that the particles precipitate at temperatures below the melting temperatures of the dry ligands. Agglomerates grow with rates that depend on the temperature: Around precipitation temperature, globular agglomerates form slowly, while at lower temperatures, fibrilar agglomerates form rapidly. All agglomerates contain random dense packings rather than crystalline superlattices. We conclude that ligand-ligand and ligand-solvent interactions of the individual particles dominate suspension stability and agglomeration kinetics. The microscopic packing is dominated by interactions between the ligands of different nanoparticles.

Born, Philip; Kraus, Tobias

2013-06-01

220

Crude Oil Price Forecasting Based on Hybridizing Wavelet Multiple Linear Regression Model, Particle Swarm Optimization Techniques, and Principal Component Analysis  

PubMed Central

Crude oil prices do play significant role in the global economy and are a key input into option pricing formulas, portfolio allocation, and risk measurement. In this paper, a hybrid model integrating wavelet and multiple linear regressions (MLR) is proposed for crude oil price forecasting. In this model, Mallat wavelet transform is first selected to decompose an original time series into several subseries with different scale. Then, the principal component analysis (PCA) is used in processing subseries data in MLR for crude oil price forecasting. The particle swarm optimization (PSO) is used to adopt the optimal parameters of the MLR model. To assess the effectiveness of this model, daily crude oil market, West Texas Intermediate (WTI), has been used as the case study. Time series prediction capability performance of the WMLR model is compared with the MLR, ARIMA, and GARCH models using various statistics measures. The experimental results show that the proposed model outperforms the individual models in forecasting of the crude oil prices series. PMID:24895666

Shabri, Ani; Samsudin, Ruhaidah

2014-01-01

221

Crude oil price forecasting based on hybridizing wavelet multiple linear regression model, particle swarm optimization techniques, and principal component analysis.  

PubMed

Crude oil prices do play significant role in the global economy and are a key input into option pricing formulas, portfolio allocation, and risk measurement. In this paper, a hybrid model integrating wavelet and multiple linear regressions (MLR) is proposed for crude oil price forecasting. In this model, Mallat wavelet transform is first selected to decompose an original time series into several subseries with different scale. Then, the principal component analysis (PCA) is used in processing subseries data in MLR for crude oil price forecasting. The particle swarm optimization (PSO) is used to adopt the optimal parameters of the MLR model. To assess the effectiveness of this model, daily crude oil market, West Texas Intermediate (WTI), has been used as the case study. Time series prediction capability performance of the WMLR model is compared with the MLR, ARIMA, and GARCH models using various statistics measures. The experimental results show that the proposed model outperforms the individual models in forecasting of the crude oil prices series. PMID:24895666

Shabri, Ani; Samsudin, Ruhaidah

2014-01-01

222

Increased oil production and reserves utilizing secondary/tertiary recovery techniques on small reservoirs in the Paradox Basin, Utah, Class II  

SciTech Connect

The primary objective of this project is to enhance domestic petroleum production by field demonstration and technology transfer of an advanced-oil-recovery technology in the Paradox basin, southeastern Utah. If this project can demonstrate technical and economic feasibility, the technique can be applied to approximately 100 additional small fields in the Paradox basin alone, and result in increased recovery of 150 to 200 million barrels (23,850,000-31,800,000 m{sup 3}) of oil. This project is designed to characterize five shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation and choose the best candidate for a pilot demonstration project for either a waterflood or carbon-dioxide-miscible flood project. The field demonstration, monitoring of field performance, and associated validation activities will take place within the Navajo Nation, San Juan County, Utah.

Chidsey, Thomas C.

2000-07-28

223

Which Microbial Communities Are Present? Using Fluorescence In Situ Hybridisation (FISH): Microscopic Techniques for Enumeration of Troublesome Microorganisms in Oil and Fuel Samples  

NASA Astrophysics Data System (ADS)

Enumeration of microbes involved in souring of oil fields and microbiologically influenced corrosion (MIC) with culture-based methods, usually yield inadequate and contradictory results. Any cultivation step will almost certainly alter the population structure of the sample and thus the results of cultivation analysis are not a good basis for mitigation decisions. The need for methods that are cultivation independent has over the past 10 years facilitated the development of several analytical methods for determination of bacterial identity, quantity, and to some extent function, applied directly to samples of the native population. In this chapter, we demonstrate the features and benefits of applying microscopic techniques to a situation often encountered in the oil and petroleum industry: Control of microbial growth in fuel storage tanks. The methods described in this chapter will focus on direct counts of specific groups of microorganisms with microscopy and these are based on the detection of genetic material and not on culturing.

Holmkvist, Lars; Østergaard, Jette Johanne; Skovhus, Torben Lund

224

Ultrasonic cavitation induced water in vegetable oil emulsion droplets--a simple and easy technique to synthesize manganese zinc ferrite nanocrystals with improved magnetization.  

PubMed

In the present investigation, synthesis of manganese zinc ferrite (Mn(0.5)Zn(0.5)Fe(2)O(4)) nanoparticles with narrow size distribution have been prepared using ultrasound assisted emulsion (consisting of rapeseed oil as an oil phase and aqueous solution of Mn(2+), Zn(2+) and Fe(2+) acetates) and evaporation processes. The as-prepared ferrite was nanocrystalline. In order to remove the small amount of oil present on the surface of the ferrite, it was subjected to heat treatment at 300 °C for 3h. Both the as-prepared and heat treated ferrites have been characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), TGA/DTA, transmission electron microscopy (TEM) and energy dispersion X-ray spectroscopy (EDS) techniques. As-prepared ferrite is of 20 nm, whereas the heat treated ferrite shows the size of 33 nm. In addition, magnetic properties of the as-prepared as well as the heat treated ferrites have also been carried out and the results of which show that the spontaneous magnetization (?(s)) of the heat treated sample (24.1 emu/g) is significantly higher than that of the as-synthesized sample (1.81 emu/g). The key features of this method are avoiding (a) the cumbersome conditions that exist in the conventional methods; (b) usage of necessary additive components (stabilizers or surfactants, precipitants) and (c) calcination requirements. In addition, rapeseed oil as an oil phase has been used for the first time, replacing the toxic and troublesome organic nonpolar solvents. As a whole, this simple straightforward sonochemical approach results in more phase pure system with improved magnetization. PMID:22113061

Sivakumar, Manickam; Towata, Atsuya; Yasui, Kyuichi; Tuziuti, Toru; Kozuka, Teruyuki; Iida, Yasuo; Maiorov, Michail M; Blums, Elmars; Bhattacharya, Dipten; Sivakumar, Neelagesi; Ashok, M

2012-05-01

225

Modifying drug release and tablet properties of starch acetate tablets by dry powder agglomeration.  

PubMed

In this study three model drugs (N-acetyl-D-glucosamine (NAG), anhydrous caffeine, and propranolol hydrochloride) were agglomerated with starch acetate (SA) by mixing the binary powders on a stainless steel (SS) plate. Agglomeration was induced by triboelectrification of the particles during mixing, and it was evaluated as a method to achieve controlled drug release rate. These agglomerates, mixed with different amounts of a disintegrant, were compressed into tablets whose dissolution characteristics were determined. Triboelectric measurements showed that when the drugs were in contact with SS, charges of the opposite polarity were generated to SA (+) and caffeine and NAG (-) promoting adhesion. Instead, propranolol HCl was charged with the same polarity as SA. SEM micrographs showed that smaller caffeine particles, in spite of their larger negative charge, agglomerated less efficiently with SA than larger NAG particles. This emphasizes the importance of particle size in the agglomeration process. Propranolol HCl did not form agglomerates with SA since their particle sizes and charges were identical. As a result, agglomeration of powders prior to tablet compression allows for modification and control of the release rate of the drugs from the SA matrix tablets as well as the tensile strength of the tablets. PMID:17075868

Mäki, Riikka; Suihko, Eero; Rost, Susanne; Heiskanen, Minna; Murtomaa, Matti; Lehto, Vesa-Pekka; Ketolainen, Jarkko

2007-02-01

226

Development of a method for analysis of Iranian damask rose oil: combination of gas chromatography-mass spectrometry with Chemometric techniques.  

PubMed

Gas chromatography-mass spectrometry (GC-MS) combined with Chemometric resolution techniques were proposed as a method for the analysis of volatile components of Iranian damask rose oil. The essential oil of damask rose was extracted using hydrodistillation method and analyzed with GC-MS in optimized conditions. A total of 70 components were identified using similarity searches between mass spectra and MS database. This number was extended to 95 components with concentrations higher than 0.01% accounting for 94.75% of the total relative content using Chemometric techniques. For the first time in this work, an approach based upon subspace comparison is used for determination of the chemical rank of GC-MS data. The peak clusters were resolved using heuristic evolving latent projection (HELP) and multivariate curve resolution-alternating least square (MCR-ALS) by applying proper constraints, and the combination of both methods for some cases. It is concluded that a thorough analysis of the complex mixtures such as Iranian damask rose requires sophisticated GC-MS coupled with the Chemometric techniques. PMID:18611452

Jalali-Heravi, Mehdi; Parastar, Hadi; Sereshti, Hassan

2008-08-01

227

INCREASED OIL PRODUCTION AND RESERVES UTILIZING SECONDARY/TERTIARY RECOVERY TECHNIQUES ON SMALL RESERVOIRS IN THE PARADOX BASIN, UTAH  

SciTech Connect

The Paradox Basin of Utah, Colorado, and Arizona contains nearly 100 small oil fields producing from shallow-shelf carbonate buildups or mounds within the Desert Creek zone of the Pennsylvanian (Desmoinesian) Paradox Formation. These fields typically have one to four wells with primary production ranging from 700,000 to 2,000,000 barrels (111,300-318,000 m{sup 3}) of oil per field at a 15 to 20 percent recovery rate. Five fields in southeastern Utah were evaluated for waterflood or carbon-dioxide (CO{sub 2})-miscible flood projects based upon geological characterization and reservoir modeling. Geological characterization on a local scale focused on reservoir heterogeneity, quality, and lateral continuity as well as possible compartmentalization within each of the five project fields. The Desert Creek zone includes three generalized facies belts: (1) open-marine, (2) shallow-shelf and shelf-margin, and (3) intra-shelf, salinity-restricted facies. These deposits have modern analogs near the coasts of the Bahamas, Florida, and Australia, respectively, and outcrop analogs along the San Juan River of southeastern Utah. The analogs display reservoir heterogeneity, flow barriers and baffles, and lithofacies geometry observed in the fields; thus, these properties were incorporated in the reservoir simulation models. Productive carbonate buildups consist of three types: (1) phylloid algal, (2) coralline algal, and (3) bryozoan. Phylloid-algal buildups have a mound-core interval and a supra-mound interval. Hydrocarbons are stratigraphically trapped in porous and permeable lithotypes within the mound-core intervals of the lower part of the buildups and the more heterogeneous supramound intervals. To adequately represent the observed spatial heterogeneities in reservoir properties, the phylloid-algal bafflestones of the mound-core interval and the dolomites of the overlying supra-mound interval were subdivided into ten architecturally distinct lithotypes, each of which exhibits a characteristic set of reservoir properties obtained from outcrop analogs, cores, and geophysical logs. The Anasazi and Runway fields were selected for geostatistical modeling and reservoir compositional simulations. Models and simulations incorporated variations in carbonate lithotypes, porosity, and permeability to accurately predict reservoir responses. History matches tied previous production and reservoir pressure histories so that future reservoir performances could be confidently predicted. The simulation studies showed that despite most of the production being from the mound-core intervals, there were no corresponding decreases in the oil in place in these intervals. This behavior indicates gravity drainage of oil from the supra-mound intervals into the lower mound-core intervals from which the producing wells' major share of production arises. The key to increasing ultimate recovery from these fields (and similar fields in the basin) is to design either waterflood or CO{sub 2}-miscible flood projects capable of forcing oil from high-storage-capacity but low-recovery supra-mound units into the high-recovery mound-core units. Simulation of Anasazi field shows that a CO{sub 2} flood is technically superior to a waterflood and economically feasible. For Anasazi field, an optimized CO{sub 2} flood is predicted to recover a total 4.21 million barrels (0.67 million m3) of oil representing in excess of 89 percent of the original oil in place. For Runway field, the best CO{sub 2} flood is predicted to recover a total of 2.4 million barrels (0.38 million m3) of oil representing 71 percent of the original oil in place. If the CO{sub 2} flood performed as predicted, it is a financially robust process for increasing the reserves in the many small fields in the Paradox Basin. The results can be applied to other fields in the Rocky Mountain region, the Michigan and Illinois Basins, and the Midcontinent.

Thomas C. Chidsey, Jr.

2002-11-01

228

Engineering development of selective agglomeration: Task 5, Bench- scale process testing  

SciTech Connect

Under the overall objectives of DOE Contract Engineering Development of Selective Agglomeration,'' there were a number of specific objectives in the Task 5 program. The prime objectives of Task 5 are highlighted below: (1) Maximize process performance in pyritic sulfur rejection and BTU recovery, (2) Produce a low ash product, (3) Compare the performance of the heavy agglomerant process based on diesel and the light agglomerant process using heptane, (4) Define optimum processing conditions for engineering design, (5) Provide first-level evaluation of product handleability, and (6) Explore and investigate process options/ideas which may enhance process performance and/or product handleability.

Not Available

1991-09-01

229

Engineering development of selective agglomeration: Task 5, Bench- scale process testing  

SciTech Connect

Under the overall objectives of DOE Contract ``Engineering Development of Selective Agglomeration,`` there were a number of specific objectives in the Task 5 program. The prime objectives of Task 5 are highlighted below: (1) Maximize process performance in pyritic sulfur rejection and BTU recovery, (2) Produce a low ash product, (3) Compare the performance of the heavy agglomerant process based on diesel and the light agglomerant process using heptane, (4) Define optimum processing conditions for engineering design, (5) Provide first-level evaluation of product handleability, and (6) Explore and investigate process options/ideas which may enhance process performance and/or product handleability.

Not Available

1991-09-01

230

Flower-like agglomerates of hydroxyapatite crystals formed on an egg-shell membrane.  

PubMed

Flower-like hydroxyapatite agglomerates formed on the upper side and lower side of an egg-shell membrane were intensively investigated using a uniquely designed crystallizer. First the ion driving force was calculated in theory. In addition the influences of various factors, such as temperature, pH value, and holding time, on the morphology and crystallinity of the agglomerates were studied in detail by means of FESEM, TEM and XRD. It was found that flower-like hydroxyapatite agglomerates with high crystallinity can be produced under higher temperature, larger pH value, and moderated holding time. The information generated is relevant to the formation process of bone. PMID:21036558

Zhang, Ying; Liu, Yong; Ji, Xiaobo; Banks, Craig E; Song, Jiangfeng

2011-02-01

231

Agglomeration of Ni-nanoparticles in the gas phase under gravity and microgravity conditions  

NASA Astrophysics Data System (ADS)

The agglomeration of metallic nanoparticles can be performed using the well-known inert gas condensation process. Unfortunately, thermal effects such as convection are created by the heating source and as a result the turbulent aerosol avoids ideal conditions. In addition, the sedimentation of large particles and/or agglomerates influences the self-assembly of particles. These negative effects can be eliminated by using microgravity conditions. Here we present the results of the agglomeration of nanoscale Ni-particles under gravity and microgravity conditions, the latter provided by adapted microgravity platforms namely the European sounding rocket MAXUS 8 and the European Parabolic Flight aircraft, Airbus A300 Zero-G.

Lösch, S.; Iles, G. N.; Schmitz, B.; Günther, B. H.

2011-12-01

232

Magnetic agglomeration method for size control in the synthesis of magnetic nanoparticles  

DOEpatents

A method for controlling the size of chemically synthesized magnetic nanoparticles that employs magnetic interaction between particles to control particle size and does not rely on conventional kinetic control of the reaction to control particle size. The particles are caused to reversibly agglomerate and precipitate from solution; the size at which this occurs can be well controlled to provide a very narrow particle size distribution. The size of particles is controllable by the size of the surfactant employed in the process; controlling the size of the surfactant allows magnetic control of the agglomeration and precipitation processes. Agglomeration is used to effectively stop particle growth to provide a very narrow range of particle sizes.

Huber, Dale L. (Albuquerque, NM)

2011-07-05

233

Study of the material and techniques used by some nineteenth century American oil painters by means of neutron activation autoradiography  

Microsoft Academic Search

Neutron activation autoradiography and activation analysis were used to ; study techniques and material used by nineteenth century painters particularly ; Ralph A. Blakelock. These techniques can supply information on pigments as well ; as the way they are applied. (LK)

M. J. Cotter; P. Meyers; L. van Zelst; C. H. Olin; E. V. Sayre

1973-01-01

234

Effect of extraction technique on the content and antioxidant activity of crude extract of Anacyclus clavatus flowers and their essential oil composition.  

PubMed

Anacyclus clavatus is a plant used as food and remedy. The objective of this work was to study the effect of extraction technique on the antioxidant property, total phenol and flavonoid contents of crude extracts from A. clavatus flowers and their essential oil composition. 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, ferric-reducing power, ?-carotene and total antioxidant capacity assays have demonstrated the significant antioxidant ability of different crude extracts obtained by using the following extraction methods: Soxhlet, microwave heating, heat reflux (HRE) and maceration. The activity of the extract obtained by HRE was the highest (112.06 ± 2.89 ?g/mL) evaluated by the DPPH assay. Extraction of essential oil was performed by microwave-assisted hydro-distillation (MAHD) and by hydro-distillation (HD). A significant difference was observed in both essential oils, despite the common main family and major constituents, such as artemisia ketone (10.0 ± 0.8% for MAHD vs. 6.5 ± 0.5 for HD) and pinocarvone (4.1 ± 0.4% for MAHD vs. 1.1 ± 0.1% for HD). PMID:25115624

Aliboudhar, Hamza; Tigrine-Kordjani, Nacéra

2014-01-01

235

Synthesis of crystalline and amorphous, particle-agglomerated 3-D nanostructures of Al and Si oxides by femtosecond laser and the prediction of these particle sizes  

PubMed Central

We report a single step technique of synthesizing particle-agglomerated, amorphous 3-D nanostructures of Al and Si oxides on powder-fused aluminosilicate ceramic plates and a simple novel method of wafer-foil ablation to fabricate crystalline nanostructures of Al and Si oxides at ambient conditions. We also propose a particle size prediction mechanism to regulate the size of vapor-condensed agglomerated nanoparticles in these structures. Size characterization studies performed on the agglomerated nanoparticles of fabricated 3-D structures showed that the size distributions vary with the fluence-to-threshold ratio. The variation in laser parameters leads to varying plume temperature, pressure, amount of supersaturation, nucleation rate, and the growth rate of particles in the plume. The novel wafer-foil ablation technique could promote the possibilities of fabricating oxide nanostructures with varying Al/Si ratio, and the crystallinity of these structures enhances possible applications. The fabricated nanostructures of Al and Si oxides could have great potentials to be used in the fabrication of low power-consuming complementary metal-oxide-semiconductor circuits and in Mn catalysts to enhance the efficiency of oxidation on ethylbenzene to acetophenone in the super-critical carbon dioxide. PMID:23140103

2012-01-01

236

Agglomeration Multigrid for an Unstructured-Grid Flow Solver  

NASA Technical Reports Server (NTRS)

An agglomeration multigrid scheme has been implemented into the sequential version of the NASA code USM3Dns, tetrahedral cell-centered finite volume Euler/Navier-Stokes flow solver. Efficiency and robustness of the multigrid-enhanced flow solver have been assessed for three configurations assuming an inviscid flow and one configuration assuming a viscous fully turbulent flow. The inviscid studies include a transonic flow over the ONERA M6 wing and a generic business jet with flow-through nacelles and a low subsonic flow over a high-lift trapezoidal wing. The viscous case includes a fully turbulent flow over the RAE 2822 rectangular wing. The multigrid solutions converged with 12%-33% of the Central Processing Unit (CPU) time required by the solutions obtained without multigrid. For all of the inviscid cases, multigrid in conjunction with an explicit time-stepping scheme performed the best with regard to the run time memory and CPU time requirements. However, for the viscous case multigrid had to be used with an implicit backward Euler time-stepping scheme that increased the run time memory requirement by 22% as compared to the run made without multigrid.

Frink, Neal; Pandya, Mohagna J.

2004-01-01

237

Blending of agglomerates into powders 1: Quantification of abrasion rate.  

PubMed

A very common situation in the pharmaceutical arena is that a small amount of cohesive drug substance needs to be distributed in a large bulk of free-flowing filler such as lactose. The key topic of attention is that aggregates of a cohesive drug substance need to be sufficiently broken up in an acceptable time-frame. This implies that there is need for a better mechanistic understanding of the blending process and the reduction in size of the aggregates. The purpose of this study is to obtain more insight in the mechanisms that lead to the break up of assemblies of powder particles in a moving powder bed. The break up of aggregates was studied by application of so-called brittle Calibrated Test Particles (bCTPs). These are well-defined aggregates with brittle fracture properties. The dominant mechanism of the break up of these aggregates is abrasion by multiple impacts. There is evidence of a relationship between strength (expressed as porosity) of the bCTPs and rate of abrasion. This is often a slow process and the rate is determined not only by the (mechanical) properties of the agglomerates and process conditions, but also by the particle size distribution of the bulk filler. PMID:20015470

Willemsz, Tofan A; Oostra, Wim; Hooijmaijers, Ricardo; de Vegt, Onno; Morad, Nasim; Vromans, Herman; Frijlink, Henderik W; Van der Voort Maarschalk, Kees

2010-03-15

238

Reducing adhesion and agglomeration within a cloud of combustible particles  

NASA Astrophysics Data System (ADS)

The study of combustible particle clouds inside flame tubes is of fundamental scientific interest as well as a practical concern. Only the suspended concentration is important to the combustion process, so that assurances must be provided that a minimum of particles adheres to the tube wall. This paper demonstrates experimentally the ability to minimize adhesion and agglomeration of acoustically-mixed lycopodium particles within a 5-cm diameter lexan flame tube. The area density of particles (ADP) adhering to the wall of bare lexan tubes was measured at greater than 100 particles/sq mm. The nature of adhesion was found to be clearly electrostatic, with the ADP level aggravated by increased mixing time, vigor, and the concentration of particles. Increases in the conductivity of the air and the tube wall did not affect ADP levels substantially. However, the observed adhesion was reduced to less than 10 p/sq mm when the air was ionized by use of an alpha emitter mounted on the inner walls of the flame tube.

Ross, Howard D.

1988-07-01

239

The Physics of Protoplanetesimal Dust Agglomerates. V. Multiple Impacts of Dusty Agglomerates at Velocities Above the Fragmentation Threshold  

NASA Astrophysics Data System (ADS)

In recent years, a number of new experiments have advanced our knowledge on the early growth phases of protoplanetary dust aggregates. Some of these experiments have shown that collisions between porous and compacted agglomerates at velocities above the fragmentation threshold velocity can lead to growth of the compact body, when the porous collision partner fragments upon impact and transfers mass to the compact agglomerate. To obtain a deeper understanding of this potentially important growth process, we performed laboratory and drop tower experiments to study multiple impacts of small, highly porous dust-aggregate projectiles onto sintered dust targets. The projectile and target consisted of 1.5 ?m monodisperse, spherical SiO2 monomers with volume filling factors of 0.15 ± 0.01 and 0.45 ± 0.05, respectively. The fragile projectiles were accelerated by a solenoid magnet and combined with a projectile magazine with which 25 impacts onto the same spot on the target could be performed in vacuum. We measured the mass-accretion efficiency and the volume filling factor for different impact velocities between 1.5 and 6.0 m s^{-1}. The experiments at the lowest impact speeds were performed in the Bremen drop tower under microgravity conditions to allow partial mass transfer also for the lowest adhesion case. Within this velocity range, we found a linear increase of the accretion efficiency with increasing velocity. In the laboratory experiments, the accretion efficiency increases from 0.12 to 0.21 in units of the projectile mass. The recorded images of the impacts showed that the mass transfer from the projectile to the target leads to the growth of a conical structure on the target after less than 100 impacts. From the images, we also measured the volume filling factors of the grown structures, which ranged from 0.15 (uncompacted) to 0.40 (significantly compacted) with increasing impact speed. The velocity dependency of the mass-transfer efficiency and the packing density of the resulting aggregates augment our knowledge of the aggregate growth in protoplanetary disks and should be taken into account for future models of protoplanetary dust growth.

Kothe, Stefan; Güttler, Carsten; Blum, Jürgen

2010-12-01

240

THE PHYSICS OF PROTOPLANETESIMAL DUST AGGLOMERATES. V. MULTIPLE IMPACTS OF DUSTY AGGLOMERATES AT VELOCITIES ABOVE THE FRAGMENTATION THRESHOLD  

SciTech Connect

In recent years, a number of new experiments have advanced our knowledge on the early growth phases of protoplanetary dust aggregates. Some of these experiments have shown that collisions between porous and compacted agglomerates at velocities above the fragmentation threshold velocity can lead to growth of the compact body, when the porous collision partner fragments upon impact and transfers mass to the compact agglomerate. To obtain a deeper understanding of this potentially important growth process, we performed laboratory and drop tower experiments to study multiple impacts of small, highly porous dust-aggregate projectiles onto sintered dust targets. The projectile and target consisted of 1.5 {mu}m monodisperse, spherical SiO{sub 2} monomers with volume filling factors of 0.15 {+-} 0.01 and 0.45 {+-} 0.05, respectively. The fragile projectiles were accelerated by a solenoid magnet and combined with a projectile magazine with which 25 impacts onto the same spot on the target could be performed in vacuum. We measured the mass-accretion efficiency and the volume filling factor for different impact velocities between 1.5 and 6.0 m s{sup -1}. The experiments at the lowest impact speeds were performed in the Bremen drop tower under microgravity conditions to allow partial mass transfer also for the lowest adhesion case. Within this velocity range, we found a linear increase of the accretion efficiency with increasing velocity. In the laboratory experiments, the accretion efficiency increases from 0.12 to 0.21 in units of the projectile mass. The recorded images of the impacts showed that the mass transfer from the projectile to the target leads to the growth of a conical structure on the target after less than 100 impacts. From the images, we also measured the volume filling factors of the grown structures, which ranged from 0.15 (uncompacted) to 0.40 (significantly compacted) with increasing impact speed. The velocity dependency of the mass-transfer efficiency and the packing density of the resulting aggregates augment our knowledge of the aggregate growth in protoplanetary disks and should be taken into account for future models of protoplanetary dust growth.

Kothe, Stefan; Guettler, Carsten; Blum, Juergen, E-mail: s.kothe@tu-bs.d [Institut fuer Geophysik und extraterrestrische Physik, Technische Universitaet zu Braunschweig, Mendelssohnstr. 3, D-38106 Braunschweig (Germany)

2010-12-10

241

Bed material agglomeration during fluidized bed combustion. Technical progress report, September 30, 1992--December 31, 1992  

SciTech Connect

The purpose of this project is to determine the physical and chemical reactions which led to the undesired agglomeration of bed material during fluidized bed combustion and to relate these reactions to specific causes. Survey of industrial-scale fluidized bed combustors is being conducted to determine the occurrence of bed agglomeration and the circumstances under which agglomeration took place. This task should be finished by the end of February. Samples of bed material, agglomerate material, and boiler deposits are being requested from boiler operators as part of the survey. Once received, these sample will be analyzed to determine chemical and mineralogic composition. The bulk chemical determination will be performed using x-ray fluorescence and inductively coupled plasma-optical emission (ICP). Mineralogy will be detected by x-ray diffraction (XRD). Chemical and mineral reactions will be determined by scanning electron microscopy, optical microscopy, and electron microprobe.

Brown, R.C.; Dawson, M.R.; Noble, S.

1993-02-01

242

Development of acoustic agglomerator. Monthly technical progress report for April 1-30, 1984  

SciTech Connect

This report is a monthly technical progress statement of the devlopment of an acoustic agglomerator. The report is divided into two parts including the establishment of performance criteria and a sound source evaluation.

Not Available

1984-05-20

243

Discrete element modeling of the microstructure of fine particle agglomerates in sheared dilute suspension  

NASA Astrophysics Data System (ADS)

The fragmentation and restructuring under shear of agglomerates of fine mineral particles are studied with the Distinct Element Method. The model used takes into account contact forces, van der Waals forces, and hydrodynamic forces computed with the free-draining approximation. A loose initial agglomerate is submitted to a constant shear rate until reaching a quasi-stationary state, where the number, size and structure of fragment of agglomerates can be considered as constant. The influence of shear stress and size of particles on the characteristics of agglomerates at equilibrium is studied. Fragmentation is controlled by a non-dimensional number, depending on the radius of the particles, shear rate and maximal adhesion force.

Kimbonguila Manounou, A.; Rémond, S.

2014-10-01

244

NDT of on and offshore oil and gas installations using the alternating current field measurement (ACFM) technique  

SciTech Connect

Offshore inspection has been carried out in the UK waters for the last 25 years, but the techniques used have until recently remained stagnant. Innovative work carried out by University College London produced the mathematical modeling of the alternating current field measurement technique, which was then further developed and commercialized into a field usable technique. During detection and sizing trials, this technique proved to be better than even MPI for detection and as good as the existing sizing techniques. This was a major advance in NDT technology, a technique that could detect surface breaking defects through paint and other coatings of various thickness, then accurately size them in terms of length and depth. The technique was adopted for subsea inspection of welds and was then used for topside applications of numerous types. The adaptability of the technique to different materials and coatings has made it acceptable to not only the offshore industry, but it is now widely used in the petrochemical industry, the power generation industry, and in aerospace and outer space. A range of equipment and probes has allowed this new technology to be used where other techniques could not be applied.

Raine, G.A. [Technical Software Consultants Ltd., Milton Keynes (United Kingdom); Smith, N. [IESCO Inc., San Pedro, CA (United States)

1996-04-01

245

Foreign Manufacturing Investment in China: The Role of Industrial Agglomeration and Industrial Linkages  

Microsoft Academic Search

AbstractThis paper investigates the forces that determine the industrial distribution of foreign manufacturing investment. It highlights the importance of industrial agglomeration and industrial linkage in attracting foreign investment to manufacturing industries. Using panel data for two-digit manufacturing industries in Beijing during the period of 1999-2004, this study finds that geographically agglomerated industries with strong intra-industrial linkages are indeed attractive to

Canfei He

2008-01-01

246

Experimental investigation of agglomeration during combustion of aluminized solid propellants in an acceleration field  

Microsoft Academic Search

Agglomeration during combustion of solid rocket propellants in an acceleration field up to 60 was studied experimental. In\\u000a the experiments, the acceleration direction and magnitude were varied. The amount, chemical composition, and particle size\\u000a of the agglomerates and the structure of the surface layer were determined as functions of the acceleration magnitude and\\u000a direction. The most significant feature of the

V. A. Babuk; V. A. Vasil’ev; A. N. Potekhin

2009-01-01

247

Agglomeration of Ni-nanoparticles in the gas phase under gravity and microgravity conditions  

Microsoft Academic Search

The agglomeration of metallic nanoparticles can be performed using the well-known inert gas condensation process. Unfortunately, thermal effects such as convection are created by the heating source and as a result the turbulent aerosol avoids ideal conditions. In addition, the sedimentation of large particles and\\/or agglomerates influences the self-assembly of particles. These negative effects can be eliminated by using microgravity

S Lösch; G N Iles; B Schmitz; B H Günther

2011-01-01

248

Bed material agglomeration during fluidized bed combustion. Technical progress report, January 1, 1994--March 31, 1994  

SciTech Connect

Laboratory combustion tests conducted this quarter support the hypothesis that localized reducing conditions promote formation of agglomerates in the bed of fluidized bed boilers. These tests were designed to simulate localized reducing conditions found in commercial fluidized bed combustors. Localized reducing conditions may occur from either poor lateral bed mixing or oxygen-starved bed conditions due to the coal feed configuration. It was found-that agglomeration can occur at lower theoretical air values while operating temperatures are within the range of fluidized bed boilers. Cohesion of bed particles appears to take place very rapidly when theoretical air in the bed approaches 70%. These tests also indicate that bed temperature, pressure drop, oxygen and carbon dioxide concentrations are affected by agglomeration. Agglomeration appears to result in: (1) An increase in the frequency of pressure fluctuations (bed pressure drop). (2) An increase in the magnitude of pressure fluctuations (bed pressure drop.) (3) A possible decrease in bed pressure differential over time. In addition, there appears to be an increase in the amount of available oxygen and a decrease in CO{sub 2}. Agglomerates formed in the laboratory are being subjected to mineralogical analyses which will then be compared to similar analyses of agglomerates removed from commercial boilers.

Brown, R.C.; Dawson, M.R.; Smeenk, J.L.

1994-04-01

249

Effects of operating conditions on agglomeration and habit of paracetamol crystals in anti-solvent crystallization  

NASA Astrophysics Data System (ADS)

Effects of agitation speed and feeding rate on agglomeration and habit of paracetamol crystals in anti-solvent crystallization from water-acetone mixture are reported. Water is used as anti-solvent and is added in a semi-batch manner to a baffled 1-l crystallizer equipped with a marine-type impeller. A simple new method to characterize agglomeration degree has been proposed. Results show that agglomeration degree of crystals depends on particle size and elevated agitation reduces agglomeration degree of big particles. Particle mean size exhibits a maximum with increasing agitation intensity in the range of 200-600 rpm, which is explained from the perspective of anti-solvent dispersion and crystal agglomeration/disruption. Agglomeration degree of products deteriorates with increasing feeding rate ranging from 1 to 20 g/min due to enhanced nucleation. Crystal habit changes when feeding rate is altered, mainly in the faces of [0 0 1] and [1 1 0]. Focused beam reflectance measurement (FBRM) was used to monitor indirectly the particle size distribution in situ. The data demonstrated that FBRM may potentially be used as a tool to control crystallization process.

Yu, Z. Q.; Tan, R. B. H.; Chow, P. S.

2005-06-01

250

Effect of hydration repulsion on nanoparticle agglomeration evaluated via a constant number Monte-Carlo simulation.  

PubMed

The effect of hydration repulsion on the agglomeration of nanoparticles in aqueous suspensions was investigated via the description of agglomeration by the Smoluchowski coagulation equation using constant number Monte-Carlo simulation making use of the classical DLVO theory extended to include the hydration repulsion energy. Evaluation of experimental DLS measurements for TiO2, CeO2, SiO2, and ?-Fe2O3 (hematite) at high IS (up to 900 mM) or low |?-potential| (?1.35 mV) demonstrated that hydration repulsion energy can be above electrostatic repulsion energy such that the increased overall repulsion energy can significantly lower the agglomerate diameter relative to the classical DLVO prediction. While the classical DLVO theory, which is reasonably applicable for agglomeration of NPs of high |?-potential| (?>35 mV) in suspensions of low IS (?<1 mM), it can overpredict agglomerate sizes by up to a factor of 5 at high IS or low |?-potential|. Given the potential important role of hydration repulsion over a range of relevant conditions, there is merit in quantifying this repulsion energy over a wide range of conditions as part of overall characterization of NP suspensions. Such information would be of relevance to improved understanding of NP agglomeration in aqueous suspensions and its correlation with NP physicochemical and solution properties. PMID:25566787

Liu, Haoyang Haven; Lanphere, Jacob; Walker, Sharon; Cohen, Yoram

2015-01-30

251

Effect of hydration repulsion on nanoparticle agglomeration evaluated via a constant number Monte–Carlo simulation  

NASA Astrophysics Data System (ADS)

The effect of hydration repulsion on the agglomeration of nanoparticles in aqueous suspensions was investigated via the description of agglomeration by the Smoluchowski coagulation equation using constant number Monte–Carlo simulation making use of the classical DLVO theory extended to include the hydration repulsion energy. Evaluation of experimental DLS measurements for TiO2, CeO2, SiO2, and ?-Fe2O3 (hematite) at high IS (up to 900 mM) or low |?-potential| (?1.35 mV) demonstrated that hydration repulsion energy can be above electrostatic repulsion energy such that the increased overall repulsion energy can significantly lower the agglomerate diameter relative to the classical DLVO prediction. While the classical DLVO theory, which is reasonably applicable for agglomeration of NPs of high |?-potential| (?>35 mV) in suspensions of low IS (?<1 mM), it can overpredict agglomerate sizes by up to a factor of 5 at high IS or low |?-potential|. Given the potential important role of hydration repulsion over a range of relevant conditions, there is merit in quantifying this repulsion energy over a wide range of conditions as part of overall characterization of NP suspensions. Such information would be of relevance to improved understanding of NP agglomeration in aqueous suspensions and its correlation with NP physicochemical and solution properties.

Haven Liu, Haoyang; Lanphere, Jacob; Walker, Sharon; Cohen, Yoram

2015-01-01

252

Quantitative characterization of agglomerate abrasion in a tumbling blender by using the Stokes number approach.  

PubMed

Removal of microcrystalline cellulose agglomerates in a dry-mixing system (lactose, 100 M) predominantly occurs via abrasion. The agglomerate abrasion rate potential is estimated by the Stokes abrasion (StAbr) number of the system. The StAbr number equals the ratio between the kinetic energy density of the moving powder bed and the work of fracture of the agglomerate. Basically, the StAbr number concept describes the blending condition of the dry-mixing system. The concept has been applied to investigate the relevance of process parameters on agglomerate abrasion in tumbling blenders. Here, process parameters such as blender rotational speed and relative fill volumes were investigated. In this study, the StAbr approach revealed a transition point between abrasion rate behaviors. Below this transition point, a blending condition exists where agglomerate abrasion is dominated by the kinetic energy density of the powder blend. Above this transition point, a blending condition exists where agglomerates show (undesirable) slow abrasion rates. In this situation, the blending condition is mainly determined by the high fill volume of the filler. PMID:23250711

Willemsz, Tofan A; Nguyen, Tien Thanh; Hooijmaijers, Ricardo; Frijlink, Henderik W; Vromans, Herman; van der Voort Maarschalk, Kees

2013-03-01

253

Effect of the Additives on the Desulphurization Rate of Flash Hydrated and Agglomerated CFB Fly Ash  

NASA Astrophysics Data System (ADS)

CFB fly ash from separators was mixed with water or the mixture of water and additives under the temperature of 363K by use of a blender. Then, this compound of fly ash and water or additives was pumped into a CFB combustion chamber by a sludge pump. Because the temperature of flue gas was high in CFB, the fly ash was hydrated fast and agglomerated in the same time. Through this process, the size of agglomerating fly ash is larger than the original particle and the relative residence time of agglomerated fly ash in CFB becomes longer. Therefore, the rate of utility of calcium in fly ash improves and the content of carbon in fly ash decreases. This results in a low Ca/S and low operational cost for CFB boiler. The additive is one key factor, which affects the rate of desulfurization of agglomerated fly ash. Effect of different additives on rate of desulfurization is not same. Cement and limestone are beneficiated to sulfur removal of agglomerated fly ash, but sodium silicate does not devote to the rate of sulfur removal of agglomerated fly ash.

Li, D. X.; Li, H. L.; Xu, M.; Lu, J. F.; Liu, Q.; Zhang, J. S.; Yue, G. X.

254

Compactibility of agglomerated mixtures of calcium carbonate and microcrystalline cellulose.  

PubMed

The tablet tensile strength (T) of agglomerated mixtures of microcrystalline cellulose-Avicel PH 102 (MC), calcium carbonate (CC) and polyvinylpyrrolidone (Povidone, PVP), lubricated with magnesium stearate (MS), and formed under a compaction pressure (P(c)) ranging up to 618MPa has been determined. The compactibility was defined through: ln(-ln(1-T/T(max)))=Slope x lnP(c)+Intercept. MC/CC mixtures added of an agglutinant, before and after lubrication, show an important positive effect on their tablet tensile strength compared to a lineal relationship. This positive effect becomes smaller with decreasing compaction pressures. By different mixing methods, the higher the mixing efficiency the higher the compactibility, following the order: spray-dried>wet massing>tumble mixing. The compactibility of MC/CC/PVP spray-dried mixtures with calcium carbonate content from 20 to 60% was equal to or greater than that of pure microcrystalline cellulose. After lubrication with 2% MS the compactibility decreased, only the mixture with the maximal tablet tensile strength attained the tensile strength of pure microcrystalline cellulose. The presence of the binder, the lubricant and higher compaction pressures allow the accommodation of higher calcium carbonate proportions in the mixtures, at the maximal tablet tensile strength of the series. The lubricant decreases in a greater extent the compactibility of mixtures with a continuous phase of MC/PVP than that of CC/PVP. This is attributed to the plastic behavior of the MC/PVP continuous phase compared to a calcium carbonate continuous phase able to disrupt the Povidone and the possible lubricant coatings allowing a stronger interparticle interaction. PMID:12753762

Garzón Serra, María de Lourdes; Villafuerte Robles, Leopoldo

2003-06-01

255

Increased oil production and reserves utilizing secondary/tertiary recovery techniques on small reservoirs in the Paradox Basin, Utah. Technical progress report, January 1--March 31, 1996  

SciTech Connect

The primary objective of this project is to enhance domestic petroleum production by demonstration and technology transfer of an advanced oil recovery technology in the Paradox basin, southeastern Utah. If this project can demonstrate technical and economic feasibility, the technique can be applied to approximately 100 additional small fields in the Paradox basin alone, and result in increased recovery of 150 to 200 million barrels of oil. This project is designed to characterize five shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation and choose the best candidate for a pilot demonstration project for either a waterflood or carbon dioxide-(CO{sub 2}-)flood project. The field demonstration, monitoring of field performance, and associated validation activities will take place in the Paradox basin within the Navajo Nation. The results of this project will be transferred to industry and other researchers through a petroleum extension service, creation of digital databases for distribution, technical workshops and seminars, field trips, technical presentations at national and regional professional meetings, and publication in newsletters and various technical or trade journals.

Allison, M.L.

1996-04-30

256

Increased oil production and reserves utilizing secondary/tertiary recovery techniques on small reservoirs in the Paradox basin, Utah. Technical progress report, July 1--September 30, 1995  

SciTech Connect

The primary objective of this project is to enhance domestic petroleum production by demonstration and technology transfer of an advanced oil recovery technology in the Paradox basin, southeastern Utah. If this project can demonstrate technical and economic feasibility, the technique can be applied to approximately 100 additional small fields in the Paradox basin alone, and result in increased recovery of 150 to 200 million barrels of oil. This project is designed to characterize five shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation and choose the best candidate for a pilot demonstration project for either a waterflood or carbon dioxide-(CO{sub 2}-) flood project. The field demonstration, monitoring of field performance, and associated validation activities will take place in the Paradox basin within the Navajo Nation. The results of this project will be transferred to industry and other researchers through a petroleum extension service, creation of digital databases for distribution, technical workshops and seminars, field trips, technical presentations at national and regional professional meetings, and publication in newsletters and various technical or trade journals. Four activities continued this quarter as part of the geological and reservoir characterization of carbonate mound buildups in the Paradox basin: (1) field studies, (2) development well completion operations, (3) reservoir analysis and modeling, and (4) technology transfer. This paper reviews the status.

Allison, M.L.

1995-12-01

257

Heterogeneous Shallow-Shelf Carbonate Buildups in the Paradox Basin, Utah and Colorado: Targets for Increased Oil Production and Reserves Using Horizontal Drilling Techniques  

SciTech Connect

The project's primary objective was to enhance domestic petroleum production by demonstration and transfer of horizontal drilling technology in the Paradox Basin, Utah, Colorado, Arizona, and New Mexico. If this project can demonstrate technical and economic feasibility, then the technique can be applied to approximately 100 additional small fields in the Paradox Basin alone, and result in increased recovery of 25 to 50 million barrels (4-8 million m3) of oil. This project was designed to characterize several shallow-shelf carbonate reservoirs in the Pennsylvanian (Desmoinesian) Paradox Formation, choose the best candidate(s) for a pilot demonstration project to drill horizontally from existing vertical wells, monitor well performance(s), and report associated validation activities.

Chidsey, Jr., Thomas C.; Eby, David E.; Wray, Laural L.

2001-11-26

258

Heterogeneous Shallow-Shelf Carbonate Buildups in the Paradox Basin, Utah and Colorado: Targets for Increased Oil Production and Reserves Using Horizontal Drilling Techniques  

SciTech Connect

The primary objective of this project was to enhance domestic petroleum production by demonstration and transfer of horizontal drilling technology in the Paradox basin, Utah, Colorado, Arizona, and New Mexico. If this project can demonstrate technical and economic feasibility, then the technique can be applied to approximately 100 additional small fields in the Paradox basin alone, and result in increased recovery of 25 to 50 million barrels (40-80 million m3) of oil. This project was designed to characterize several shallow-shelf carbonate reservoirs in the Pennsylvania (Desmoinesian) Paradox Formation, choose the best candidate(s) for a pilot demonstration project to drill horizontally from existing vertical wells, monitor well performances, and report associated validation activities.

Chidsey, Thomas C. Jr.; Eby, David E.; Wray, Laura L.

2001-04-19

259

Oil Classification with Fluorescence Spectroscopy Engineering Physics  

E-print Network

........................................................................14 II. Raman scattering..........................................................................15 and classification of oil spills on water surfaces. It is an overview of the laser remote sensor technique detected by these channels. The investigation used three methods to examine crude oil, heavy oil, sludge

Oldenburg, Carl von Ossietzky Universität

260

Identification of oil–gas two-phase flow pattern based on SVM and electrical capacitance tomography technique  

Microsoft Academic Search

The correct identification of two-phase flow patterns is the basis for the accurate measurement of other flow parameters in two-phase flow measurement. Electrical capacitance tomography (ECT) is a new visualization measurement technique for two-phase\\/multi-phase flows. The capacitance measurements obtained from the ECT system contain flow pattern information, and then six feature parameters are extracted. The support vector machine (SVM) has

Lifeng Zhang; Huaxiang Wang

2010-01-01

261

Bed material agglomeration during fluidized bed combustion. Technical progress report, January 1, 1995--March 31, 1995  

SciTech Connect

Experiments performed support the hypothesis that a reducing atmosphere during fluidized bed coal combustion contributes to the formation of agglomerates. Reducing conditions are imposed by controlling the amount of combustion air supplied to the combustor, 50% of theoretical in these experiments. These localized reducing conditions may arise from either poor lateral bed mixing or oxygen-starved conditions due to the coal feed locations. Deviations from steady-state operating conditions in bed pressure drop may be used to detect agglomerate formation. Interpretation of the bed pressure drop was made more straightforward by employing a moving average difference method. During steady-state operation, the difference between the moving point averages should be close to zero, within {plus_minus}0.03 inches of water. Instability within the combustor, experienced once agglomerates begin to form, can be recognized as larger deviations from zero, on the magnitude of {plus_minus}0.15 inches of water.

Brown, R.C.; Dawson, M.R.; Smeenk, J.L.

1995-04-01

262

Dry powdered aerosols of diatrizoic acid nanoparticle agglomerates as a lung contrast agent  

PubMed Central

Aerosolized contrast agents may improve the resolution of biomedical imaging modalities and enable more accurate diagnosis of lung diseases. Many iodinated compounds, such as diatrizoic acid, have been shown to be safe and useful for radiographic examination of the airways. Formulations of such compounds must be improved in order to allow imaging of the smallest airways. Here, diatrizoic acid nanoparticle agglomerates were created by assembling nanoparticles into inhalable microparticles that may augment deposition in the lung periphery. Nanoparticle agglomerates were fully characterized and safety was determined in vivo. After dry powder insufflation to rats, no acute alveolar tissue damage was observed 2 h post dose. Diatrizoic acid nanoparticle agglomerates possess the characteristics of an efficient and safe inhalable lung contrast agent. PMID:20214960

El-Gendy, Nashwa; Aillon, Kristin L.; Berkland, Cory

2010-01-01

263

Study of the temperature evolution of defect agglomerates in neutron irradiated molybdenum single crystals  

NASA Astrophysics Data System (ADS)

Small angle neutron scattering as a function of temperature, differential thermal analysis, electrical resistivity and transmission electron microscopy studies have been performed in low rate neutron irradiated single crystalline molybdenum, at room temperature, for checking the evolution of the defects agglomerates in the temperature interval between room temperature and 1200 K. The onset of vacancies mobility was found to happen in temperatures within the stage III of recovery. At around 550 K, the agglomerates of vacancies achieve the largest size, as determined from the Guinier approximation for spherical particles. In addition, the decrease of the vacancy concentration together with the dissolution of the agglomerates at temperatures higher than around 920 K was observed, which produce the release of internal stresses in the structure.

Lambri, O. A.; Zelada-Lambri, G. I.; Cuello, G. J.; Bozzano, P. B.; García, J. A.

2009-04-01

264

Molecular dynamics study of self-agglomeration of charged fullerenes in solvents  

NASA Astrophysics Data System (ADS)

The agglomeration of fullerenes in solvents is an important phenomenon that is relevant to controlled synthesis of fullerene-based nanowires as well as fullerene-based composites. The molecular aggregation in solvents depends on the atomistic interactions of fullerene with the solvent and is made complicated by the fact that fullerenes accrue negative surface charges when present in solvents such as water. In the present work, we simulated fullerenes of varying size and shape (C60, C180, C240, and C540) with and without surface charges in polar protic (water), polar aprotic (acetone), and nonpolar (toluene) solvents using molecular dynamics method. Our results demonstrate that uncharged fullerenes form agglomerates in polar solvents such as water and acetone and remain relatively dispersed in nonpolar toluene. The presence of surface charge significantly reduces agglomerate size in water and acetone. Additionally, the relative influence of surface charge on fullerene agglomeration depends on the size and geometry of the fullerene with larger fullerenes forming relatively smaller agglomerates. We evaluated the diffusion coefficients of solvent molecules within the solvation shell of fullerenes and observed that they are much lower than the bulk solvent and are strongly associated with the fullerenes as seen in the corresponding radial distribution functions. To correlate agglomerate size with the binding energy between fullerenes, we evaluated the potential of mean force between fullerenes in each solvent. Consistent with the solubility of fullerenes, binding energy between fullerenes is the greatest in water followed by acetone and toluene. The presence of charge decreases the binding energy of fullerenes in water and thus results in dispersed fullerenes.

Banerjee, Soumik

2013-01-01

265

Bed material agglomeration during fluidized bed combustion. Technical progress report, 1 April 1994--30 June 1994  

SciTech Connect

Tests were conducted to determine if observed changes in combustion conditions during agglomerate formation could be used as a diagnostic tool to predict agglomeration. Tests were performed in a laboratory-scale bubbling fluidized bed combustor. Localized reducing conditions were simulated by lowering the amount of air used for combustion while fluidization conditions were maintained with the addition of nitrogen gas. After these tests were terminated agglomerates were recovered from the bed ranging in size from 1--5 inches in diameter. During these tests, bed temperatures fluctuated between 1500 and 1700 F, but remained below the temperatures that are commonly associated with ash fouling. A divergence in bed temperatures (at the combustor wall and the center of the bed) was most likely due to a decrease in mixing within the bed as particles began to agglomerate and their mean size increased. The agglomeration and particle size increase may have also lead to a partial loss of fluidization in the bed which contributed to the localized divergence in bed temperatures. These data indicate the potential for using temperature divergence as a diagnostic tool to monitor particle agglomeration and bed mixing. Also, it was determined that the method of combustor shut-down has an effect on the decomposition of agglomerates. It was found that when the combustion test was terminated and cooled under oxidizing conditions, agglomerates could be reduced in size or eliminated from the bed. This was the case even when temperature divergences and bed pressure fluctuations indicated agglomeration was occurring during the test. In tests where the bed was cooled using nitrogen, large agglomerates were found when the bed was removed. These results are being used to develop a strategy for the remediation of agglomerates after their formation.

Brown, R.C.; Dawson, M.R.; Smeenk, J.L.

1994-07-01

266

Similarity criteria of HOSP formation at plasma processing of agglomerated particles  

NASA Astrophysics Data System (ADS)

The theoretical analysis of basic phenomena at plasma processing of the agglomerated powders, in context of hollow microspherical particles production, was fulfilled. With the use of the obtained theoretical solutions for the first time the key similarity criteria were derived that allow to formulate the requirements to plasma flow, characteristics of agglomerate and its material as well as condition of quenching of the formed hollow microdroplet which realization provides the formation of hollow microsphere with necessary characteristics, in particular, of maximal diameter and minimum thickness of shell.

Solonenko, O. P.

2014-11-01

267

BP Oil Spill November 10, 2011  

E-print Network

BP Oil Spill Qiyam Tung November 10, 2011 1 Introduction Figure 1: BP Oil spill (source: http://thefoxisblack.com/2010/05/02/the-bp-oil-spill-in-the-gulf-of-mexico/) Last year, there was a major oil spill caused major techniques to minimize the threat once it happened. What kind of damage would an oil spill like this cause

Lega, Joceline

268

In-Situ Agglomeration and De-agglomeration by Milling of Nano-Engineered Lubricant Particulate Composites for Cold Spray Deposition  

NASA Astrophysics Data System (ADS)

Nano-engineered self-lubricating particles comprised of hexagonal-boron-nitride powder (hBN) encapsulated in nickel have been developed for cold spray coating of aluminum components. The nickel encapsulant consists of several nano-sized layers, which are deposited on the hBN particles by electroless plating. In the cold spray deposition, the nickel becomes the matrix in which hBN acts as the lubricant. The coating demonstrated a very promising performance by reducing the coefficient of friction by almost 50% and increasing the wear resistance more than tenfold. The coatings also exhibited higher bond strength, which was directly related to the hardenability of the particles. During the encapsulation process, the hBN particles agglomerate and form large clusters. De-agglomeration has been studied through low- and high-energy ball milling to create more uniform and consistent particle sizes and to improve the cold spray deposition efficiency. The unmilled and milled particles were characterized with Scanning Electron Microscopy, Energy-Dispersive X-Ray Spectroscopy, BET, and hardness tests. It was found that in low-energy ball milling, the clusters were compacted to a noticeable extent. However, the high-energy ball milling resulted in breakup of agglomerations and destroyed the nickel encapsulant.

Neshastehriz, M.; Smid, I.; Segall, A. E.

2014-10-01

269

Oil Oil Everywhere  

NSDL National Science Digital Library

This math meets ecology lesson provides hands-on experiences with mixing oil and water, provides surface area information about the 2010 oil spill in the Gulf of Mexico, and gives learners opportunities to estimate small oil spills of their own making. This lesson guide includes questions for learners, assessment options, extensions, and reflection questions.

Cartwright, Lisa

2010-01-01

270

Nonlinear optical characterization of cluster dynamic in water in oil microemulsion by a pump probe laser beam technique  

NASA Astrophysics Data System (ADS)

We present a new pump probe laser beams configuration for the nonlinear optical characterization of microemulsions. We detect the variation of the on-axis optical intensity of the probe beam as generated by the concentration profile induced in an optically thin film of microemulsion by the pump beam. A mathematical model has been introduced to describe the phenomenon. The technique allows the determination of both Kerr-like optical nonlinearity and time constants and, therefore, it gives information both on cluster dimension and their shape. We discuss its application to WAD (water/AOT/decane, where AOT denotes sodium-bis-di-ethyl-sulfosuccinate) with the application of a strong electric field of optical source. Comparison between theoretical predictions and experimental results confirms the presence of giant optical nonlinearity in the absence of turbidity divergence. Chainlike shape of clusters, of the kind already reported with the application of strong electric field, could justify this result.

Vicari, L.

2002-11-01

271

World oil  

NASA Astrophysics Data System (ADS)

Results obtained through the application of 10 prominent world oil or world energy models to 12 scenarios are reported. These scenarios were designed to bound the range of likely future world oil market outcomes. Conclusions relate to oil market trends, impacts of policies on oil prices, security of oil supplies, impacts of policies on oil security problems, use of the oil import premium in policymaking, the transition to oil substitutes, and the state of the art of world oil modeling.

Sweeney, J. L.

1982-06-01

272

Composite propellant aluminum agglomeration reduction using tailored Al/PTFE particles  

NASA Astrophysics Data System (ADS)

Micron aluminum is widely used in propellants; however, performance could be significantly improved if ignition barriers could be disrupted and combustion tailored. In solid propellants for example, aluminum increases theoretical specific impulse performance, yet theoretical levels cannot be achieved largely because of two-phase flow losses. These losses could be reduced if particles quickly ignited, more gaseous products were produced, and if particle breakup occurred during combustion. To achieve altered aluminum ignition and particle combustion, this work explores the use of low level (10-30 wt.%) fluorocarbon (polytetrafluoroethylene (PTFE) or poly(carbon monofluoride) (PMF)) inclusion inside of aluminum via low or high energy mechanical activation. Aluminum/PTFE particles are found to be amenable to use in binder based energetics, having average particle sizes ranging from 15 to 78 ?m, ~2-7 m2/g, specific surface area, and combustion enthalpies as high as 20.2 kJ/g. Differential scanning calorimetry (DSC) experiments indicate high energy MA reduces both reaction and oxidation onset to ~440 °C that is far below aluminum alone. Safety testing shows these particles have high electrostatic discharge (ESD) (89.9-108 mJ), impact (> 213 cm), and friction (> 360 N) ignition thresholds. The idea of further increasing reactivity and increasing particle combustion enthalpy is explored by reducing fluorocarbon inclusion content to 10 wt.% and through the use of the strained fluorocarbon PMF. Combustion enthalpy and average particle size range from 18.9 to 28.5 kJ/g and 23.0 to 67.5 ?m, respectively and depend on MA intensity, duration, and inclusion level. Specific surface areas are high (5.3 to 34.8 m2/g) and as such, Al/PMF particles are appropriate for energetic applications not requiring a curable liquid binder. Mechanical activation reduces oxidation onset (DSC) from 555 to 480 °C (70/30 wt.%). Aluminum/PMF particles are sensitive to ESD (11.5-47.5 mJ) and some can be ignited via optical flash. Propellant aluminum agglomeration is assessed through replacement of reference aluminum powders (spherical, flake, or nanoscale) with Al/PTFE (90/10 or 70/30 wt.%) particles. The effects on burning rate, pressure dependence, and aluminum ignition, combustion, and agglomeration are quantified. Microscopic imaging shows tailored particles promptly ignite at the burning surface and appear to breakup into smaller particles. Replacement of spherical aluminum with Al/PTFE 70/30 wt.% also increases the pressure exponent from 0.36 to 0.58, which results in a 50% increase in propellant burning rate at 13.8 MPa. Combustion products were quench collected using a liquid-free technique at 2.1 and 6.9 MPa. Sizing of products indicates that composite particles result in nominally 25 ?m coarse products, which are smaller than the original, average particle size and are also 66% smaller in diameter (96% by volume) than the 76 ?m products collected from reference spherical aluminized propellant. Smaller diameter condensed phase products and more gaseous products will likely decrease two-phase flow loss and reduce slag accumulation in solid rocket motors.

Sippel, Travis R.

273

Influence of decomposition parameters on agglomeration process and total soda content in precipitated Al(OH) 3  

NASA Astrophysics Data System (ADS)

Grain size composition of precipitated Al(OH) 3 is dependent on the mechanism of decomposition process of the caustic solution which determines crystal growth process, agglomeration process and secondary nucleation. Because the literature data shows that the growth rate is very low, the agglomeration process plays an important role in increasing the initial particle size. On the other hand, the agglomeration process enables the inclusion of impurities by the grain boundary of sticking Al(OH) 3 particles, above all, the inclusion of soda Na 2O. In this paper we investigate the influence of caustic soda concentration Na 2O (c), that is the supersaturation of the solution, seed charge and seed grain size on the agglomeration and secondary nucleation processes and total soda content in precipitated Al(OH) 3. The results have shown that the factor which causes the increase of the agglomeration process also causes the increase of total soda content in precipitated Al(OH) 3.

Blagojevi?, I.; Ble?i?, D.; Vasiljevi?, R.

1999-04-01

274

Agglomerated Large Particles under Various Slurry Preparation Conditions and Their Influence on Shallow Trench Isolation Chemical Mechanical Polishing  

NASA Astrophysics Data System (ADS)

The effects of various slurry manufacturing conditions, such as suspension pH, abrasive contents, and the calcination temperature of abrasive ceramic particles on the formation of agglomerated large particles of ceria slurry were investigated. The agglomerated large particles in slurry have much influence on the micro-scratches on the wafer surface in shallow trench isolation chemical mechanical polishing (STI CMP). The formation of large agglomerated particles is affected by the conformation of the organic additives in the slurry as a function of the suspension pH and the specific surface area of the abrasive particle. Regarding the solid content, abrasive particles are more easily dispersed at lower solid loading, which prevents additional agglomeration even under acidic conditions. The influence of agglomerated large particles on STI CMP was investigated through a polishing experiment with plasma-enhanced tetra-ethyl-ortho-silicate (PETEOS) and a low-pressure chemical vapor deposition (LPCVD) nitride layer.

Kim, Dae-Hyeong; Kang, Hyun-Goo; Kim, Sang-Kyun; Paik, Ungyu; Park, Jea-Gun

2005-11-01

275

JOURNAL OF REGIONAL SCIENCE, VOL. XX, NO. X, 2010, pp. 120 AGGLOMERATION ECONOMIES: MICRODATA PANEL ESTIMATES  

E-print Network

primary concern is identification of the sources of agglomeration and evaluation of their significance output. The panel data overcome selection bias resulting from unobserved plant-level heterogeneity, information and communication technologies, *This research was supported by a Canadian Studies Faculty

276

Location of foreign manufacturers in China: Agglomeration economies and country of origin effects  

Microsoft Academic Search

Using data from China, this article finds that agglomeration economies derived from the clustering of manufacturing and foreign investment activities, combined with better access to markets, influence the location of foreign manufacturers. Foreign enterprises are attracted to cities with investment incentives, but they avoid high labour cost locations. The locational patterns also suggest country of origin effects. American, Hong Kong

Canfei He

2003-01-01

277

Evidence of zirconium nano-agglomeration in as-cast dilute U-Zr alloys  

NASA Astrophysics Data System (ADS)

Microstructure evaluation of as-cast and annealed U-Zr (Zr = 2, 6 and 10 wt.%) alloys has been carried out for the first time using positrons as a probe. The chemical signature in the matter-antimatter annihilation gamma and the positron lifetime data suggests that majority of positrons are annihilating from Zr sites in the as-cast alloys. The results have been interpreted as due to the presence of Zr nano-agglomerates in the as-cast alloys which have a higher positron affinity as compared to the rest of the U matrix. A minimum agglomerate size of ?2 nm diameter has been calculated from the difference in positron affinity between the agglomerates and the matrix. Upon annealing, the Zr signature in the annihilation gamma photons vanishes suggesting that the Zr agglomerates diffuse out of U matrix and form micron-sized precipitates. This has been confirmed by scanning electron microscopy which shows a 3 times increase in the surface density of the precipitates in the annealed alloys as compared to the as-cast ones. Shorter positron diffusion length (measured using slow positron beam) as compared to precipitate separation has been invoked to explain the observed data.

Mukherjee, S.; Kaity, S.; Saify, M. T.; Jha, S. K.; Pujari, P. K.

2014-09-01

278

Agglomeration and pecipitation by sonic-inertial means: Abstract of the state of the art  

NASA Astrophysics Data System (ADS)

Acoustic - intertial precipitation and agglomeration of aerosols are discussed. Evidence suggests that this sonic-inertial method is applicable when the gases involved derive from pyrolysis in chambers. A pilot model is proposed that supplies the necessary detailed data for the design and construction of an industrial model for large capacity.

Nepomuceno, L. X.

1984-07-01

279

Determination of aerodynamic diameters of pollen grains and their agglomerates for Western Siberia plants  

NASA Astrophysics Data System (ADS)

Results of determination of aerodynamic characteristics of 17 plants dominating the ecosystem of Western Siberia are reported. Pollen of cereals and woody plants was examined. The sedimentation velocities of single pollen grains and their agglomerates were determined. The data obtained were used to calculate the aerodynamic diameters of pollen grains of all investigated plants.

Istomin, V. L.; Koutsenogii, K. P.; Golovko, V. V.

2012-12-01

280

Do Universities Generate Agglomeration Spillovers? Evidence from Endowment Value Shocks. NBER Working Paper No. 15299  

ERIC Educational Resources Information Center

In this paper we quantify the extent and magnitude of agglomeration spillovers from a formal institution whose sole mission is the creation and dissemination of knowledge--the research university. We use the fact that universities follow a fixed endowment spending policy based on the market value of their endowments to identify the causal effect…

Kantor, Shawn; Whalley, Alexander

2009-01-01

281

Prediction of Agglomeration, Fouling, and Corrosion Tendency of Fuels in CFB Co-Combustion  

NASA Astrophysics Data System (ADS)

Prediction of agglomeration, fouling, and corrosion tendency of fuels is essential to the design of any CFB boiler. During the years, tools have been successfully developed at Foster Wheeler to help with such predictions for the most commercial fuels. However, changes in fuel market and the ever-growing demand for co-combustion capabilities pose a continuous need for development. This paper presents results from recently upgraded models used at Foster Wheeler to predict agglomeration, fouling, and corrosion tendency of a variety of fuels and mixtures. The models, subject of this paper, are semi-empirical computer tools that combine the theoretical basics of agglomeration/fouling/corrosion phenomena with empirical correlations. Correlations are derived from Foster Wheeler's experience in fluidized beds, including nearly 10,000 fuel samples and over 1,000 tests in about 150 CFB units. In these models, fuels are evaluated based on their classification, their chemical and physical properties by standard analyses (proximate, ultimate, fuel ash composition, etc.;.) alongside with Foster Wheeler own characterization methods. Mixtures are then evaluated taking into account the component fuels. This paper presents the predictive capabilities of the agglomeration/fouling/corrosion probability models for selected fuels and mixtures fired in full-scale. The selected fuels include coals and different types of biomass. The models are capable to predict the behavior of most fuels and mixtures, but also offer possibilities for further improvements.

Bariš?, Vesna; Zabetta, Edgardo Coda; Sarkki, Juha

282

Agglomerates and granules of nanoparticles as filter media for submicron particles  

Microsoft Academic Search

An experimental study on filtration of submicron solid and liquid aerosol particles by using a filter media composed of agglomerates or granules of nanoparticles is described. Fumed silica nanoagglomerates, carbon black granules, silica shells, activated carbon granules, glass beads and nanoporous hydrophobic aerogel were among the granular filter media tested and compared to a commercially available HEPA fiber-based filter. Other

Jose Quevedo; Gaurav Patel; Robert Pfeffer; Rajesh Dave

2008-01-01

283

Study of a water-cooled fluidized bed for diesel particle agglomeration  

Microsoft Academic Search

A water-cooled fluidized bed particle trap has been built and tested for diesel particle agglomeration. A theoretical formula incorporating thermophoretic mechanisms into normal fluidized bed filtration has been derived to calculate particle removal efficiency in a water-cooled fluidized bed and validated with published data and measurements from this study. Reasonably good agreement between the measurements and model predictions is achieved.

Ji Ping Shi; Roy M. Harrison

2001-01-01

284

Quasiparticle agglomerates and environmental effects in the fractional quantum Hall edge states at ? = 5/2  

SciTech Connect

We discuss how the presence of environmental effects and quasiparticle agglomerates could better reconcile the edge states theories with the experimental observations for the case of ? = 5/2. The Pfaffian and the anti-Pfaffian models will be compared in connection with experimental results identifying the latter as the best candidate.

Braggio, A. [SPIN-CNR, Via Dodecaneso 33, 16146 Genova (Italy); Carrega, M. [NEST, Istituto Nanoscienze-CNR, and Scuola Normale Superiore, I-56126, Pisa (Italy); Ferraro, D.; Magnoli, N. [Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, 16146 Genova, Italy and INFN, Via Dodecaneso 33, 16146, Genova (Italy); Sassetti, M. [Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, 16146 Genova, Italy and SPIN-CNR, Via Dodecaneso 33, 16146 Genova (Italy)

2013-12-04

285

Direct synthesis of silicon nanowires, silica nanospheres, and wire-like nanosphere agglomerates  

E-print Network

plate, whose temperature is adjustable,13 through a matching set of insulating zirconia blocksDirect synthesis of silicon nanowires, silica nanospheres, and wire-like nanosphere agglomerates J temperature synthesis has been used to generate virtually defect free SiO2 sheathed crystalline silicon

Wang, Zhong L.

286

COMPUTATIONAL STUDIES OF CONTROLLED NANOPARTICLE AGGLOMERATIONS FOR MRI-GUIDED NANOROBOTIC DRUG-DELIVERY SYSTEMS  

E-print Network

COMPUTATIONAL STUDIES OF CONTROLLED NANOPARTICLE AGGLOMERATIONS FOR MRI-GUIDED NANOROBOTIC DRUG-DELIVERY in nanorobotic drug delivery. INTRODUCTION Nanorobotic drug delivery systems guided by Magnetic Resonance Imaging (MRI) scanners have been proposed for localized drug delivery in the human body. The expectation

Mavroidis, Constantinos

287

Agglomeration of Ash in Fluidized Beds Gasifying Coal: The Godel Phenomenon  

Microsoft Academic Search

In a bed of anthracite or bituminous coke fluidized by air at 10 to 15 meters per second at 1200 degrees to 1400 degrees C, molten ash forms beads on the surface of a coke particle, some exuding from its interior. The beads merge and detach themselves to grow further as loose fluidized ash agglomerates of low carbon content.

Joseph Yerushalmi; Morris Kolodney; Robert A. Graff; Arthur M. Squires; Richard D. Harvey

1975-01-01

288

Factors Governing the Development of High Tech Industry Agglomerations: A Tale of Three Cities  

Microsoft Academic Search

GLASMEIER A. (1988) Factors governing the development of high tech industry agglomerations: a tale of three cities, Reg. Studies22, 287–301. High tech industries are thought to precipitate structural change in local economies through the creation of backward and forward linkages and new firm spinoffs. Case studies of high tech firms and products indicate interindustry linkage development is closely associated with

Amy Glasmeier

1988-01-01

289

Regional Policy Agglomeration: Arctic Policy in Canada and the United States  

Microsoft Academic Search

Regional policies addressing urban policy, rural policy and policies with specific regional targets tend to evolve from the consideration of disparate issues that impact the designated region rather than as co-ordinated strategies. We label this aggregation of disparate policies as policy agglomeration. We examine this phenomenon for domestic aspects of Arctic policies in Canada and the United States. Arctic policy

Peter J May; Bryan D Jones; Betsi E Beem; Emily A Neff-Sharum; Melissa K Poague

2005-01-01

290

Impacts of Agglomeration on Call Centre Operations: Evidence from North West England  

Microsoft Academic Search

Peck F. and Cabras I. Impacts of agglomeration on call centre operations: evidence from North West England, Regional Studies. Call centres have until fairly recently provided a significant source of employment growth in the peripheral regions of the UK. Despite the potential for locational dispersal throughout the urban hierarchy, however, call centres tend to be highly concentrated in larger urban

Frank Peck; Ignazio Cabras

2009-01-01

291

Beneficiation and agglomeration process to utilize low-grade ferruginous manganese ore fines  

Microsoft Academic Search

Characterisation, beneficiation and agglomeration studies were carried out to develop a utilization strategy for typical Indian low grade manganese ore fines. The major mineral phases found are pyrolusite, hematite, goethite, clay, feldspar and quartz. QEMSCAN and Sink–Float studies suggested that 40% of manganese minerals are in liberated form, whereas 30% are locked with iron minerals. Classification followed by two-stage high

Veerendra Singh; Tamal K. Ghosh; Y. Ramamurthy; Vilas Tathavadkar

2011-01-01

292

Why the Valley Went First: Agglomeration and Emergence in Regional Inventor Networks  

E-print Network

their careers. #12;Abstract: Are the inventor networks of Silicon Valley more densely connected than those, Silicon Valley demonstrates a dramatic agglomeration of its inventors, such that half of them can trace 128 in Massachusetts. While many of their counterparts in California's Silicon Valley were still

Sekhon, Jasjeet S.

293

Survey and evaluation of instream habitat and stock restoration techniques for wild pink and chum salmon. Restoration study number 105-1 (restoration project 93063). Exxon Valdez oil spill state/federal natural resource damage assessment final report  

SciTech Connect

This project is the result of a three-year survey of the Exxon Valdez oil spill impact area to identify appropriate and cost-effective instream habitat restoration techniques for salmon, including spawning channels and improvement of fish passage through fish ladders or step-pool structures to overcome physical or hydrological barriers. Additional wild salmon stock rehabilitation measures include stream-side incubation boxes, remote egg-taking, incubation at existing hatcheries for fry stocking in oil-impacted streams, and fry rearing. Study results include the identification of the most promising instream habitat restoration projects in each of the spill-impacted areas.

Willette, T.M.; Dudiak, N.C.; Honnold, S.G.; Carpenter, G.; Dickson, M.

1995-08-01

294

Iron Oxide Nanoparticle Agglomeration Influences Dose-Rates and Modulates Oxidative Stress Mediated Dose-Response Profiles In Vitro  

SciTech Connect

Spontaneous agglomeration of engineered nanoparticles (ENPs) is a common problem in cell culture media which can confound interpretation of in vitro nanotoxicity studies. The authors created stable agglomerates of iron oxide nanoparticles (IONPs) in conventional culture medium, which varied in hydrodynamic size (276 nm-1.5 ?m) but were composed of identical primary particles with similar surface potentials and protein coatings. Studies using C10 lung epithelial cells show that the dose rate effects of agglomeration can be substantial, varying by over an order of magnitude difference in cellular dose in some cases. Quantification by magnetic particle detection showed that small agglomerates of carboxylated IONPs induced greater cytotoxicity and redox-regulated gene expression when compared with large agglomerates on an equivalent total cellular IONP mass dose basis, whereas agglomerates of amine-modified IONPs failed to induce cytotoxicity or redox-regulated gene expression despite delivery of similar cellular doses. Dosimetry modelling and experimental measurements reveal that on a delivered surface area basis, large and small agglomerates of carboxylated IONPs have similar inherent potency for the generation of ROS, induction of stress-related genes and eventual cytotoxicity. The results suggest that reactive moieties on the agglomerate surface are more efficient in catalysing cellular ROS production than molecules buried within the agglomerate core. Because of the dynamic, size and density-dependent nature of ENP delivery to cells in vitro, the biological consequences of agglomeration are not discernible from static measures of exposure concentration (?g/ml) alone, highlighting the central importance of integrated physical characterisation and quantitative dosimetry for in vitro studies. The combined experimental and computational approach provides a quantitative framework for evaluating relationships between the biocompatibility of nanoparticles and their physical and chemical characteristics.

Sharma, Gaurav; Kodali, Vamsi K.; Gaffrey, Matthew J.; Wang, Wei; Minard, Kevin R.; Karin, Norman J.; Teeguarden, Justin G.; Thrall, Brian D.

2013-07-31

295

Evaluation of charge and agglomeration behavior of TiO2 nanoparticles in ecotoxicological media.  

PubMed

The dynamic nature of nanoparticle (NP) agglomeration behavior is of paramount interest to many current studies in environmental nanoscience and nano(eco)toxicology because agglomeration affects the NP bioavailability and toxicity. The present study investigates the surface charge and agglomeration behavior of TiO2 NPs in four different ecotoxicological media (OECD algae, OECD L_variegatus, hardwater and plant media) and two different electrolytes KCl (200mM) and CaCl2 (50mM). TiO2 NPs were positively charged, and the zeta potential varied from +1.9mV in hardwater (at pH7.1) to +24.5mV in CaCl2 electrolyte (at pH7.4) in all media except algae media, where the zeta potential was -6.7mV (at pH7.7). Despite the differences in the pH and the surface charge of TiO2 NPs in the different media, an immediate agglomeration of the NPs in all standard ecotoxicological media was observed with aggregate sizes in the micrometer scale, as the measured zeta potentials were insufficient to prevent TiO2 NP agglomeration. The isoelectric point (pHiep) of TiO2 NPs in the studied media varied in the range (6.8-7.6), which was attributed to preferential association of anions and cations to TiO2; that is the pHiep decreases with the increased concentration of Cl and increases with the increased concentrations of Na and Mg. Despite the complexity of the ecotoxicological media and the presence of a mixture of different monovalent and divalent electrolytes, the agglomeration kinetics in the media follows the DVLO theory where two distinct agglomeration rates (slow, reaction limited regime and fast, diffusion limited regime) were observable. The critical coagulation concentration (CCC) of TiO2 NPs in the ecotoxicological media varied from 17.6 to 54.0% v/v standard media in UHPW, due to differences in media pH and TiO2 NP surface charge. In the ecotoxicological media (hardwater, L-variegatus and plant), where TiO2 NPs are positively charged, the CCC decrease with the increased divalent anions (act as counter ions) concentration in the media, again in good agreement with the DLVO theory. PMID:25432129

Nur, Y; Lead, J R; Baalousha, M

2014-11-25

296

Oil pollution signatures by remote sensing.  

NASA Technical Reports Server (NTRS)

Study of the possibility of developing an effective remote sensing system for oil pollution monitoring which would be capable of detecting oil films on water, mapping the areal extent of oil slicks, measuring slick thickness, and identifying the oil types. In the spectral regions considered (ultraviolet, visible, infrared, microwave, and radar), the signatures were sufficiently unique when compared to the background so that it was possible to detect and map oil slicks. Both microwave and radar techniques are capable of operating in adverse weather. Fluorescence techniques show promise in identifying oil types. A multispectral system will be required to detect oil, map its distribution, estimate film thickness, and characterize the oil pollutant.

Catoe, C. E.; Mclean, J. T.

1972-01-01

297

Sonic enhanced ash agglomeration and sulfur capture. Quarterly technical progress report, April--June 1995  

SciTech Connect

A major concern with the utilization of coal in directly fired gas turbines is the control of particulate emissions and reduction of sulfur dioxide, and alkali vapor from combustion of coal, upstream of the gas turbine. Much research and development has been sponsored on methods for particulate emissions control and the direct injection of calcium-based sorbents to reduce SO{sub 2} emission levels. The results of this research and development indicate that both acoustic agglomeration of particulates and direct injection of sorbents have the potential to become a significant emissions control strategy. The Sonic Enhanced Ash Agglomeration and Sulfur Capture program focuses upon the application of an MTCI proprietary invention (Patent No. 5,197,399) for simultaneously enhancing sulfur capture and particulate agglomeration of the combustor effluent. This application can be adapted as either a {open_quotes}hot flue gas cleanup{close_quotes} subsystem for the current concepts for combustor islands or as an alternative primary pulse combustor island in which slagging, sulfur capture, particulate agglomeration and control, and alkali gettering as well as NO{sub x} control processes become an integral part of the pulse combustion process. The goal of the program is to support the DOE mission in developing coal-fired combustion gas turbines. In particular, the MTCI proprietary process for bimodal ash agglomeration and simultaneous sulfur capture will be evaluated and developed. The technology embodiment of the invention provides for the use of standard grind, moderately beneficiated coal and WEM for firing the gas turbine with efficient sulfur capture and particulate emission control upstream of the turbine. The process also accommodates injection of alkali gettering material if necessary. The proposed technology provides for practical, reliable, and capital (and O&M) cost-effective means of protection for the gas turbine from impurities in the coal combustor effluent.

NONE

1995-08-01

298

A new stochastic approach for the simulation of agglomeration between colloidal particles.  

PubMed

This paper presents a stochastic approach for the simulation of particle agglomeration, which is addressed as a two-step process: first, particles are transported by the flow toward each other (collision step) and, second, short-ranged particle-particle interactions lead either to the formation of an agglomerate or prevent it (adhesion step). Particle collisions are treated in the framework of Lagrangian approaches where the motions of a large number of particles are explicitly tracked. The key idea to detect collisions is to account for the whole continuous relative trajectory of particle pairs within each time step and not only the initial and final relative distances between two possible colliding partners at the beginning and at the end of the time steps. The present paper is thus the continuation of a previous work (Mohaupt M., Minier, J.-P., Tanière, A. A new approach for the detection of particle interactions for large-inertia and colloidal particles in a turbulent flow, Int. J. Multiphase Flow, 2011, 37, 746-755) and is devoted to an extension of the approach to the treatment of particle agglomeration. For that purpose, the attachment step is modeled using the DLVO theory (Derjaguin and Landau, Verwey and Overbeek) which describes particle-particle interactions as the sum of van der Waals and electrostatic forces. The attachment step is coupled with the collision step using a common energy balance approach, where particles are assumed to agglomerate only if their relative kinetic energy is high enough to overcome the maximum repulsive interaction energy between particles. Numerical results obtained with this model are shown to compare well with available experimental data on agglomeration. These promising results assert the applicability of the present modeling approach over a whole range of particle sizes (even nanoscopic) and solution conditions (both attractive and repulsive cases). PMID:24111685

Henry, Christophe; Minier, Jean-Pierre; Pozorski, Jacek; Lefèvre, Grégory

2013-11-12

299

Ultrasonic Cavitation induced Water in Vegetable oil emulsion droplets - A Simple and Easy Technique to Synthesize Manganese Zinc Ferrite Nanocrystals with improved magnetisation  

Microsoft Academic Search

In the present investigation, synthesis of manganese zinc ferrite (Mn0.5Zn0.5Fe2O4) nanoparticles with narrow size distribution have been prepared using ultrasound assisted emulsion (consisting of rapeseed oil as an oil phase and aqueous solution of Mn+2, Zn+2 and Fe+2 acetates) and evaporation processes. The as-prepared ferrite was nanocrystalline. In order to remove the small amount of oil present on the surface

Manickam Sivakumar; Atsuya Towata; Kyuichi Yasui; Toru Tuziuti; Teruyuki. Kozuka; Yasuo Iida; Michail M. Maiorov; Elmars Blums; Dipten Bhattacharya; Neelagesi Sivakumar; Ashok M

300

CONSOLIDATION OF K BASIN SLUDGE DATA AND EXPERIENCES ON AGGLOMERATE FORMATION  

SciTech Connect

The formation of high sludge strength agglomerates is a key concern to the Sludge Treatment Project (STP) to ensure the sludge can be retrieved after planned storage for up to 10 years in Sludge Transport and Storage Containers (STSC) at T Plant. This report addresses observations of agglomerate formation, conditions that the data shows lead to agglomeration, the frequency of agglomerate formation and postulated physiochemical mechanisms that may lead to agglomeration. Although the exact underlying chemistry of K Basin sludge agglomerate formation is not known, the factors that lead to agglomeration formation, based on observations, are as follows: (1) High Total Uranium Content (i.e., sample homogeneity and influence from other constituents); (2) Distribution of Uranium Phases (i.e., extent of conversion from uraninite to uranium oxide hydroxide compounds); (3) Sample Dry-out (loss of cover water); (4) Elevated temperature; (5) Solubility ofU(IV) phases vs. U(VI) phases; and (6) Long storage times. Agglomerated sludge has occurred infrequently and has only been observed in four laboratory samples, five samples subjected to hydrothermal testing (performed for 7 to 10 hours at {approx}185 C and 225 psig), and indirectly during six sampling events in the KE Basin. In the four laboratory samples where agglomerates were observed, the agglomerates exhibited high shear strength and the sample container typically had to be broken to remove the solids. The total uranium content (dry basis) for the four samples (KE Pit, KC-2/3 SS, KC-2/3 M250 and 96-13) were {approx}8 wt%, {approx}59.0 wt%, 68.3 wt% and 82 wt%. The agglomerates that were present during the six sampling events were undoubtedly disturbed and easily broken apart during sample collection, thus no agglomerates were observed in subsequent laboratory analyses. The highest shear strengths measured for K Basin sludge samples were obtained after hydrothermal treatment (7 to 10 hr at 185 C) of high-uranium-content KE canister sludge. The unconfined compressive strength of samples from this testing, measured by a pocket penetrometer, infers that their shear strength may be between 120 kPa and 170 kPa (PNNL-16496). These short-duration hydrothermal tests were conducted at temperatures much greater than the temperature of the T Plant canyon cells (-7 C to 33 C); however, the strength results provide an initial bounding target for sludge stored for many years, and an upper range for simulants (042910-53451-TP02 Rev 1). Sampling and characterization activities conducted in 2009 have measured the total uranium content and speciation for sludge stored in Engineered Containers SCS-CON-220, -240, -250, and -260 (PNNL-19035). Based on on-going testing that has measured the shear strength of uranium samples containing varying uranium (IV) to uranium (VI) ratios and the characterization of the Engineered Containers SCS-CON-220, -240, -250, and -260, it is unlikely that agglomerates will form on a large scale in this sludge. The highest measured total uranium concentration in the Engineered Container SCS-CON-220 sludge is 35.2 wt% and only 4 wt% to 6 wt% (dry) in Engineered Containers SCS-CON -240, -250, and -260. The uranium concentrations in Engineered Containers SCS-CON-220, -240, -250, and -260 sludge are below the threshold for agglomerate formation. Settler sludge however is estimated to contain {approx} 80 wt% (dry) total uranium, which could lead to the formation of high strength agglomerates depending on the relative concentrations of U(IV) and U(VI) compounds. One of the chief concerns of the STP is sludge dry-out. Samples archived in PNNL hot cells have been known to dry out and form hard clods of material, which are then difficult to reconstitute (HNF-6705). In 1996, all but one of the samples archived at the 222-S Laboratory dried out. These samples were composed of sludge collected from the KE Basin floor and Weasel Pit. However, in the STP's current design plans for sludge stored in STSCs at T Plant, there are provisions for continual water level observation and periodic

HILL SR

2010-06-10

301

Oil spill identification  

Microsoft Academic Search

To unambiguously identify spilled oils and petroleum products and to link them to the known sources are extremely important in settling questions of environmental impact and legal liability. This article briefly reviews the most recent development and advances of chemical fingerprinting and data interpretation techniques which are most frequently used in oil spill identification studies, including recognition of relative distribution

Zhendi Wang; Merv Fingas; David S Page

1999-01-01

302

Oil Oil Everywhere  

NSDL National Science Digital Library

This lesson plan makes real world connections as students explore the ability to estimate the surface area of an oil spill. The lesson provides surface area information about the 2010 oil spill in the Gulf of Mexico, and gives students opportunities to estimate small oil spills of their own making. This lesson includes two students activity sheets, one fractional amount overhead sheet, assessment and extension suggestions, and questions for reflection.

Lisa Cartwright

2010-01-01

303

MICROBIAL POPULATION CHANGES DURING BIOREMEDIATION OF AN EXPERIMENTAL OIL SPILL  

EPA Science Inventory

Three crude oil bioremediation techniques were applied in a randomized block field experiment simulating a coastal oil-spill. Four treatments (no oil control, oil alone, oil + nutrients, and oil + nutrients + an indigenous inoculum) were applied. In-situ microbial community str...

304

Separating wax from hydrocarbon mixture boiling in the lubricating oil range  

SciTech Connect

A method is described of pretreating a hydrocarbon oil mixture bailing in the lubricating oil range and containing dissolved wax, comprising the steps of reducing the solubility for the wax so as to cause dissolved wax in the oil to form a dispersion of wax particles in the oil mixture and introducing free excess charge which is net unipolar into the oil mixture, whereby wax particle agglomeration and particle size growth occurs. A method is also described wherein a first oil solvent liquid is added to the waxy oil mixture to form an admixture, the admixture is cooled to the cloud point of the admixture in the absence of any introduced free excess charge. Then a second oil solvent liquid is added to the admixture. The second oil solvent liquid a lower solubility for wax than for the admixture, so as to cause the wax to precipitate as wax particles. The free excess charge is introduced into the admixture of waxy oil mixture and first and second oil solvents, to bring about agglomeration and growth of the precipitated wax particles.

Ryan, D.G.; Cerkanowicz, A.E.; Chimenti, R.J.L.; Mintz, D.J.

1986-12-09

305

Studies of the morphology and dynamics of flame-generated agglomerates using dynamic light scattering  

NASA Astrophysics Data System (ADS)

Accurate determination of the morphology and dynamics of aerosols consisting of agglomerated sub-micron sized particulates is needed for soot formation studies, process monitoring in flame-based materials synthesis applications, and pollution control studies. The objective of the current study is to investigate the application of dynamic light scattering (DLS) to flames as an extension of current measurement technologies. Unlike previous DLS flame studies, conventional polarized DLS is supplemented with depolarized DLS measurements to account for the agglomerates' anisotropy. Because unavailable relationships between the agglomerates' morphological parameters and the Brownian translational and rotational diffusion coefficients under non-continuum conditions are required for accurately determining agglomerate morphology from DLS flame measurements, the potential of combining DLS-determined diffusion coefficients with independently-determined morphology measurements to provide the necessary experimental relationships is investigated. For this study DLS measurements and thermophoretic agglomerate sampling were performed on chainlike iron oxide agglomerates occurring within a 1/2/prime' diameter Fe(CO)5-seeded CO/O2 diffusion flame. Systematic detection system errors in the DLS measurements, caused by dead time and afterpulsing, were virtually eliminated by cross- correlating the outputs of two separate photomultiplier tubes. The accompanying decrease in the signal-to-noise ratio was compensated by increasing the incident laser power and experiment duration time. This duration time increase was accomplished by combining the data from multiple five-minute experiments because of severe iron oxide deposition on the burner and flame stabilizer occurring with longtime, continuous flame operation. Accurate depolarized DLS data was thus generated from a flame environment for the first time. Inverse Laplace transform analyses of the DLS data using CONTIN produced unacceptable fits of the data. Cumulants fits were more accurate but systematically produced negative second cumulant coefficients, which prevent a complete linewidth distribution analysis and indicate the presence of invalid assumptions used in the conventional theoretical DLS interpretations. Additional experiments implicated incident beam nonuniformities as a partial cause of this effect. Average diffusion coefficients extracted from the first cumulants exhibited an order-of- magnitude agreement with theoretical estimates based on ex situ morphology and flame temperature measurements.

Waguespack, Glenn Michael

1997-12-01

306

In-Situ Observations of Interaction Between Particulate Agglomerates and an Advancing Planar Solid/Liquid Interface: Microgravity Experiments  

NASA Technical Reports Server (NTRS)

Results are reported of directional solidification experiments on particulate agglomerate pushing and engulfment by a planar solid/liquid (s/1) interface. These experiments were conducted on the Space Shuttle Columbia during the United States Microgravity Payload 4 (USMP-4) Mission. It was found that the pushing to engulfment transition velocity, V(sub ct),, for agglomerates depends not only on their effective size but also their orientation with respect to the s/l interface. The analytical model for predicting V(sub cr) of a single particle was subsequently enhanced to predict V(sub cr) of the agglomerates by considering their shape factor and orientation.

Sen, S.; Juretzko, F.; Stefanescu, D. M.; Dhindaw, B. K.; Curreri, P. A.

1999-01-01

307

In Situ Observations of Interaction Between Particulate Agglomerates and an Advancing Planar Solid/Liquid Interface: Microgravity Experiments  

NASA Technical Reports Server (NTRS)

Results are reported of directional solidification experiments on particulate agglomerate pushing and engulfment by a planar solid/liquid (s/l) interface. These experiments were conducted on the Space Shuttle Columbia during the United States Microgravity Payload 4 (USMP-4) Mission. It was found that the pushing to engulfment transition velocity, V(sub cr) for agglomerates depends not only on their effective size but also their orientation with respect to the s,1 interface. The analytical model for predicting V(sub cr) of a single particle was subsequently enhanced to predict V(sub cr) of the agglomerates by considering their shape factor and orientation.

Sen, S.; Juretzko, F.; Stafanescu, D. M.; Dhindaw, B. K.; Curreri, P. A.

1999-01-01

308

Formulation techniques for nanofluids.  

PubMed

Fluids with suspended nanoparticles, commonly known as nanofluids, may be formulated to improve the thermal performance of industrial heat transfer systems and applications. Nanofluids may show enhanced thermal and electrical properties such as thermal conductivity, viscosity, heat transfer coefficient, dielectric strength, etc. However, stability problems may arise as nanoparticles usually have the tendency to agglomerate and sediment producing deterioration in the increment of these properties. In this review, we discuss patents that report advances in the formulation of nanofluids including: production methods, selection of components (nanoparticles, base fluid and surfactants), their chemical compositions and morphologies, and characterization techniques. Finally, current and future directions in the development of nanofluid formulation are discussed. PMID:24330043

Rivera-Solorio, Carlos I; Payán-Rodríguez, Luis A; García-Cuéllar, Alejandro J; Ramón-Raygoza, E D; L Cadena-de-la-Peña, Natalia; Medina-Carreón, David

2013-11-01

309

Survey and evaluation of instream habitat and stock restoration techniques for wild pink and chum salmon. Restoration study number 105-1 (restoration project 93063). Exxon Valdez oil spill state\\/federal natural resource damage assessment final report  

Microsoft Academic Search

This project is the result of a three-year survey of the Exxon Valdez oil spill impact area to identify appropriate and cost-effective instream habitat restoration techniques for salmon, including spawning channels and improvement of fish passage through fish ladders or step-pool structures to overcome physical or hydrological barriers. Additional wild salmon stock rehabilitation measures include stream-side incubation boxes, remote egg-taking,

T. M. Willette; N. C. Dudiak; S. G. Honnold; G. Carpenter; M. Dickson

1995-01-01

310

The Preparation and Characterization of Poly(lactide-co-glycolide) Microparticles. II. The Entrapment of a Model Protein Using a (Water-in-Oil)inWater Emulsion Solvent Evaporation Technique  

Microsoft Academic Search

Poly(lactide-co-glycolide) (PLG) microparticles with entrapped antigens have recently been investigated as controlled-release vaccines. This paper describes the preparation of PLG microparticles with an entrapped model antigen, ovalbumin (OVA), using a (water-in-oil)-in-water emulsion solvent evaporation technique. In a series of experiments, the effects of process parameters on particle size and OVA entrapment were investigated. It was found that smooth, spherical microparticles

Hayley Jeffery; Stanley S. Davis; Derek T. O'Hagan

1993-01-01

311

A protocol for assessing the effectiveness of oil spill dispersants in stimulating the biodegradation of oil.  

PubMed

Dispersants are important tools in oil spill response. Taking advantage of the energy in even small waves, they disperse floating oil slicks into tiny droplets (<70 ?m) that entrain in the water column and drift apart so that they do not re-agglomerate to re-form a floating slick. The dramatically increased surface area allows microbial access to much more of the oil, and diffusion and dilution lead to oil concentrations where natural background levels of biologically available oxygen, nitrogen, and phosphorus are sufficient for microbial growth and oil consumption. Dispersants are only used on substantial spills in relatively deep water (usually >10 m), conditions that are impossible to replicate in the laboratory. To date, laboratory experiments aimed at following the biodegradation of dispersed oil usually show only minimal stimulation of the rate of biodegradation, but principally because the oil in these experiments disperses fairly effectively without dispersant. What is needed is a test protocol that allows comparison between an untreated slick that remains on the water surface during the entire biodegradation study and dispersant-treated oil that remains in the water column as small dispersed oil droplets. We show here that when this is accomplished, the rate of biodegradation is dramatically stimulated by an effective dispersant, Corexit 9500. Further development of this approach might result in a useful tool for comparing the full benefits of different dispersants. PMID:23943003

Prince, Roger C; Butler, Josh D

2014-08-01

312

Effect of drying phase on the agglomerates prepared by spherical crystallization.  

PubMed

In this paper, differences in porosity, compressive strength and tablet- forming ability of carbamazepine crystals agglomerated under similar condition, but subjected to different drying temperatures are reported. The agglomerates were prepared by spherical crystallization method and thereafter dried without agitation at different temperature. An increased drying temperature did not affect the shape and structure texture of dried particles and did not cause them to fracture. Drying of particles at higher temperature suppressed the particle contraction as a consequence of fast evaporation and hence produced particles of larger mean diameter, higher porosity and thus lower compressive strength than those dried at lower temperature. Through a relationship with particle porosity, the drying rate also affected the ability of particles to form tablets. PMID:25561911

Maghsoodi, Maryam; Yari, Zahra

2015-01-01

313

Effect of Drying Phase on the Agglomerates Prepared by Spherical Crystallization  

PubMed Central

In this paper, differences in porosity, compressive strength and tablet- forming ability of carbamazepine crystals agglomerated under similar condition, but subjected to different drying temperatures are reported. The agglomerates were prepared by spherical crystallization method and thereafter dried without agitation at different temperature. An increased drying temperature did not affect the shape and structure texture of dried particles and did not cause them to fracture. Drying of particles at higher temperature suppressed the particle contraction as a consequence of fast evaporation and hence produced particles of larger mean diameter, higher porosity and thus lower compressive strength than those dried at lower temperature. Through a relationship with particle porosity, the drying rate also affected the ability of particles to form tablets. PMID:25561911

Maghsoodi, Maryam; Yari, Zahra

2015-01-01

314

High efficiency shale oil recovery  

SciTech Connect

The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated on a small scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although an oil shale batch sample is sealed in the batch kiln from the start until the end of the run, the process conditions for the batch are the same as the conditions that an element of oil shale would encounter in a continuous process kiln. Similar chemical and physical conditions (heating, mixing, pyrolysis, oxidation) exist in both systems.The two most important data objectives in this phase of the project are to demonstrate (1) that the heat recovery projected for this project is reasonable and (2) that an oil shale kiln will run well and not plug up due to sticking and agglomeration. The following was completed this quarter. (1) Twelve pyrolysis runs were made on five different oil shales. All of the runs exhibited a complete absence of any plugging, tendency. Heat transfer for Green River oil shale in the rotary kiln was 84.6 Btu/hr/ft[sup 2]/[degrees]F, and this will provide for ample heat exchange in the Adams kiln. (2) One retorted residue sample was oxidized at 1000[degrees]F. Preliminary indications are that the ash of this run appears to have been completely oxidized. (3) Further minor equipment repairs and improvements were required during the course of the several runs.

Adams, D.C.

1993-04-22

315

Problems and prospects of investigating the formation and evolution of agglomerates by the sampling method  

Microsoft Academic Search

Problems related to the interpretation of information obtained from an analysis of collected particles of condensed combustion\\u000a products of aluminized propellants are considered. It is shown that the difficulties that arise are due to three main factors:\\u000a the complex statistical character of the combustion of heterogeneous propellants, which results in formation of agglomerates\\u000a with a substantially polydisperse distribution in size

O. G. Glotov; V. E. Zarko; V. V. Karasev

2000-01-01

316

Quench collection of nano-aluminium agglomerates from combustion of sandwiches and propellants  

Microsoft Academic Search

An experimental investigation has been carried out to measure the size of nano-aluminium agglomerates emerging from the combustion of nano-aluminized sandwiches and composite solid propellants. Nano-aluminium of median size of 50nm produced in-house by the electrical wire explosion method is used in these samples. Propellants with different sizes of coarse and fine ammonium perchlorate are considered. Surface features of sandwiches

K. Jayaraman; S. R. Chakravarthy; R. Sarathi

2011-01-01

317

Combustion of single and agglomerated aluminum particles in solid rocket motor flows  

Microsoft Academic Search

Single and agglomerated aluminum droplets were studied in a solid rocket motor (SRM) test chamber with optical access to the internal flow at 6--22 atm and 2300 K. The chamber was pressurized by burning a main grain AP\\/HTPB propellant, and the burning aluminum droplets were generated by a smaller aluminized solid propellant sample, center-mounted in the flow. A 35 mm

John Charles Melcher IV

2001-01-01

318

Recent satellite-based trends of tropospheric nitrogen dioxide over large urban agglomerations worldwide  

NASA Astrophysics Data System (ADS)

Trends in tropospheric nitrogen dioxide (NO2) concentrations over 66 large urban agglomerations worldwide have been computed using data from the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) instrument onboard the Envisat platform for the period August 2002 to March 2012. A seasonal model including a linear trend was fitted to the satellite-based time series over each site. The results indicate distinct spatial patterns in trends. While agglomerations in Europe, North America, and some locations in East Asia/Oceania show decreasing tropospheric NO2 levels on the order of -5 % yr-1, rapidly increasing levels of tropospheric NO2 are found for agglomerations in large parts of Asia, Africa, and South America. The site with the most rapidly increasing absolute levels of tropospheric NO2 was found to be Tianjin in China with a trend value of 3.04 (±0.47) × 1015 molecules cm-2 yr-1, whereas the site with the most rapidly increasing relative trend was Kabul in Afghanistan with 14.3 (±2.2) % yr-1. In total, 34 sites exhibited increasing trends of tropospheric NO2 throughout the study period, 24 of which were found to be statistically significant. A total of 32 sites showed decreasing levels of tropospheric NO2 during the study period, of which 20 sites did so at statistically significant magnitudes. Overall, going beyond the relatively small set of megacities investigated previously, this study provides the first consistent analysis of recent changes in tropospheric NO2 levels over most large urban agglomerations worldwide.

Schneider, P.; Lahoz, W. A.; van der A, R.

2014-09-01

319

In Situ Treatment of Thermal RF Plasma Processed Nanopowders to Control their Agglomeration and Dispersability  

Microsoft Academic Search

Titanium carbonitride nanoparticles have been produced in an inductively coupled thermal plasma and subsequently modified\\u000a using a surfactant that has been deposited in situ on their surface in-flight. The surfactant was injected in the reactor\\u000a while the nanoparticles are still dispersed in the gas phase, allowing the coating of primary particles instead of the corresponding\\u000a agglomerates. In contrast to naked

M. Leparoux; Y. Leconte; A. Wirth; Th. Buehler

2010-01-01

320

Colloidal stability of suspended and agglomerate structures of settled carbon nanotubes in different aqueous matrices.  

PubMed

Carbon nanotubes (CNTs) are often processed in suspended form and therefore a release of CNT-suspensions into the aquatic environment is plausible. In this study, the behaviour of two physico-chemically very different CNT types in the presence of varying, environmentally relevant calcium-containing media was investigated, including the long-term colloidal stability and the sedimentary structures of settled CNTs. Calcium induced CNT flocculation, however, the stability of the CNTs in the medium did not monotonously decrease with increasing calcium concentration. At intermediate calcium concentrations (0.5-1.5 mM Ca) pre-dispersed CNTs were stabilized in humic acid medium to similar, temporarily even to higher degree than in the absence of calcium. Between pH 5 and 8 only at the highest pH an influence on CNT stability was observed by either promoting flocculation or stabilisation depending on the CNT type. Humic acid stabilized CNTs much better than fulvic acid. Generally, the colloidal stability of the long, thick CNTs with higher surface oxygen content was less affected by the media composition. An investigation of the settled CNT material using analytical electron microscopy revealed the presence of spheroidal, bundle-like and net like CNT-agglomerate structures. Calcium possibly acted as bridging agent linking CNTs in a network like manner, temporarily increasing the CNT concentrations stabilized in the supernatants due to the low density of these structures. With increasing settling time the CNTs formed a fluffy sediment layer at the bottom of the reaction vessels. Bundle-like CNT agglomerates were also observed within that layer of settled CNTs, possibly caused by calcium neutralizing the surface charges. Furthermore, the CNT suspensions contained spheroidal CNT agglomerates, most likely residues from the original dry powder that were not disaggregated. The analysis of settled CNT material is a novelty and illustrates CNT agglomerate structures possibly accumulating in the sediments of aquatic systems subsequent to CNT emissions. PMID:23582307

Schwyzer, Irène; Kaegi, Ralf; Sigg, Laura; Nowack, Bernd

2013-08-01

321

High-technology agglomeration and the labor market: the case of Silicon Valley  

Microsoft Academic Search

In this paper the pattern of labor-market activity associated with major high-technology agglomerations within the USA are examined, drawing upon the results of a mailed questionnaire survey of firms in the semiconductor industry. The analysis is focused upon the cluster of specialized semiconductor firms in Silicon Valley, to determine the contribution of local labor-market processes to the growth and development

D P Angel

1991-01-01

322

Particle Trajectories and Agglomeration/Accumulation in Branching Arteries subjected to Orbital Atherectomy  

PubMed Central

Background: The transport of particles in surrogate and actual arterial geometries has been investigated synergistically by experimentation and numerical simulation. The motivating application for this work is orbital atherectomy which spawns a particle cloud in the process of debulking plaque from arterial walls. Methods: Paired simulations and experiments were performed to prove the capability of the simulation model to predict both fluid and particle motions in branched arterial geometries. The verified model was then employed to predict the pattern of fluid flow in an actual multi-branched arterial geometry, including the flowrates passing through each of the individual branches. These predictions are in very good agreement with experimental data. Focus was then shifted to the issues of particle agglomeration within the flowing fluid and particle accumulation on the vessel walls. Once again, a synergistic approach was used. Flow visualization was employed to track the particle motions and to identify possible particle agglomeration within the fluid. Results and Conclusions: Accumulation of particles on walls was identified by measuring size distributions of effluent and residue within the artery. Scanning Electron Microscopy (SEM) evaluation showed evidence of a size-based sorting as the particles passed through vessels. It was found that plaque-facsimile particles resisted particle-particle agglomeration. They also did not accumulate to the wall of the facsimile artery. In addition, simulations showed that if particle-wall accumulation were to occur, it would be limited to very small regions in the artery branches. PMID:21643425

Helgeson, Zach L; Jenkins, Jed S; Abraham, John P; Sparrow, Ephraim M

2011-01-01

323

Sedimentation of agglomerated nanoparticles under cell culture conditions studied by image based analysis  

NASA Astrophysics Data System (ADS)

Toxic effects of nanoparticles can be analyzed with alveolar macrophages in vitro. To quantify exposure of cells to particles we analyzed the sedimentation of nanoparticle agglomerates in cell culture medium (MEM) by means of phase contrast microscopy. Particles were suspended by brief ultrasonication in MEM and pipetted into a glass bottom culture dish on the stage of a Nikon-Biostation under cell culture condition. Successive images were captured from the lowermost optical plane and were converted into binary images. The number of agglomerates (N) as well as the particle-covered area (A) were determined by image analyses. Typically, N increased to a maximum value before it partially decayed due to overlapping and/or optical interference of particles, and finally became constant. In contrast, A increased in a monophasic manner. By means of mathematical modeling we identified the endpoint of sedimentation of particle agglomerates, which is an important though a largely neglected event in most cell culture experiments. This endpoint could be calculated from an approximated model function. As the method can be employed in the presence of cells, a parallel evaluation of particle sedimentation and particle uptake appears possible.

Schippritt, Darius; Wiemann, Martin; Lipinski, Hans-Gerd

2010-04-01

324

Investigations on agglomeration and haemocompatibility of vitamin E TPGS surface modified berberine chloride nanoparticles.  

PubMed

The objective of the present study is to investigate the influence of surface modification on systemic stability of NPs. Vitamin E TPGS (1% w/v) was used for surface modification of berberine chloride nanoparticles. Naked and surface modified NPs were incubated in different SBFs (pH 6.8 and 7.4) with or without bile salts and human plasma. NPs were observed for particle agglomeration and morphology by particle size analyzer and TEM, respectively. The haemocompatibility studies were conducted on developed NPs to evaluate their safety profile. The surface modified NPs were stable compared to naked NPs in different SBFs due to the steric stabilization property of vitamin E TPGS. Particle agglomeration was not seen when NPs were incubated in SBF (pH 6.8) with bile salts. No agglomeration was observed in NPs after their incubation in plasma but particle size of the naked NPs increased due to adhesion of plasma proteins. The TEM images confirmed the particle size results. DSC and FT-IR studies confirmed the coexistence of TPGS in surface modified NPs. The permissible haemolysis, LDH release, and platelet aggregation revealed that NPs were compatible for systemic administration. Thus, the study illustrated that the surface modification is helpful in the maintenance of stability of NPs in systemic conditions. PMID:25162037

Vuddanda, Parameswara Rao; Rajamanickam, Vijayakumar Mahalingam; Yaspal, Madhu; Singh, Sanjay

2014-01-01

325

Investigations on Agglomeration and Haemocompatibility of Vitamin E TPGS Surface Modified Berberine Chloride Nanoparticles  

PubMed Central

The objective of the present study is to investigate the influence of surface modification on systemic stability of NPs. Vitamin E TPGS (1% w/v) was used for surface modification of berberine chloride nanoparticles. Naked and surface modified NPs were incubated in different SBFs (pH 6.8 and 7.4) with or without bile salts and human plasma. NPs were observed for particle agglomeration and morphology by particle size analyzer and TEM, respectively. The haemocompatibility studies were conducted on developed NPs to evaluate their safety profile. The surface modified NPs were stable compared to naked NPs in different SBFs due to the steric stabilization property of vitamin E TPGS. Particle agglomeration was not seen when NPs were incubated in SBF (pH 6.8) with bile salts. No agglomeration was observed in NPs after their incubation in plasma but particle size of the naked NPs increased due to adhesion of plasma proteins. The TEM images confirmed the particle size results. DSC and FT-IR studies confirmed the coexistence of TPGS in surface modified NPs. The permissible haemolysis, LDH release, and platelet aggregation revealed that NPs were compatible for systemic administration. Thus, the study illustrated that the surface modification is helpful in the maintenance of stability of NPs in systemic conditions. PMID:25162037

Vuddanda, Parameswara Rao; Rajamanickam, Vijayakumar Mahalingam; Yaspal, Madhu; Singh, Sanjay

2014-01-01

326

Integrated low emission cleanup system for direct coal-fueled turbines (electrostatic agglomeration)  

SciTech Connect

The objective of this contract was to investigate the removal of SO[sub x] and particulate matter from direct coal fired combustion gas streams at high temperature and high pressure conditions. This investigation was to be accomplished through a bench scale testing and evaluation program for SO[sub x] removal and the innovative particulate collection concept of particulate growth through electrostatic agglomeration followed by high efficiency mechanical collection. The process goal was to achieve control better than that required by 1979 New Source Performance Standards. During Phase I, the designs of the combustor and gas cleanup apparatus were successfully completed. Hot gas cleanup was designed to be accomplished at temperature levels between 1800[degrees] and 2500[degrees]F at pressures up to 15 atmospheres. The combustor gas flow rate could be varied between 0.2--0.5 pounds per second. The electrostatic agglomerator residence time could be varied between 0.25 to 3 seconds. In Phase II, all components were fabricated, and erected successfully. Test data from shakedown testing was obtained. Unpredictable difficulties in pilot plant erection and shakedown consumed more budget resources than was estimated and as a consequence DOE, METC, decided ft was best to complete the contract at the end of Phase II. Parameters studied in shakedown testing revealed that high-temperature high pressure electrostatics offers an alternative to barrier filtration in hot gas cleanup but more research is needed in successful system integration between the combustor and electrostatic agglomerator.

Quimby, J.M.; Kumar, K.S.

1992-01-01

327

Gold nanoparticle-protein agglomerates as versatile nanocarriers for drug delivery.  

PubMed

The fabrication of a versatile nanocarrier based on agglomerated structures of gold nanoparticle (Au NP)-lysozyme (Lyz) in aqueous medium is reported. The carriers exhibit efficient loading capacities for both hydrophilic (doxorubicin) and hydrophobic (pyrene) molecules. The nanocarriers are finally coated with an albumin layer to render them stable and also facilitate their uptake by cancer cells. The interaction between agglomerated structures and the payloads is non-covalent. Cell viability assay in vitro showed that the nanocarriers by themselves are non-cytotoxic, whereas the doxorubicin-loaded ones are cytotoxic, with efficiencies higher than that of the free drug. Transmission electron microscopy and fluorescence microscopy along with flow cytometry analysis confirm the uptake of the drug-loaded nanocarriers by a human cervical cancer HeLa cell line. Field-emission scanning electron microscopy reveals the formation of apoptotic bodies leading to cell death, confirming the release of the payloads from the nanocarriers into the cell. Overall, the findings suggest the fabrication of novel Au NP-protein agglomerate-based nanocarriers with efficient drug-loading and -releasing capabilities, enabling them to act as multimodal drug-delivery vehicles. PMID:23447544

Khandelia, Rumi; Jaiswal, Amit; Ghosh, Siddhartha Sankar; Chattopadhyay, Arun

2013-10-25

328

The impact of solution agglomeration on the deposition of self-assembled monolayers  

SciTech Connect

Self-assembled monolayers (SAMS) are commonly produced by immersing substrates in organic solutions containing trichlorosilane coupling agents. Unfortunately, such deposition solutions can also form alternate structures including inverse micelles and lamellar phases. The formation of alternate phases is one reason for the sensitivity of SAM depositions to factors such as the water content of the deposition solvent. If such phases are present, the performance of thin films used for applications such as minimization of friction and stiction in micromachines can be seriously compromised. Inverse micelle formation has been studied in detail for depositions involve 1H-, 1H-, 2H-, 2H-perfluorodecyltrichlorosilane (FDTS) in isooctane. Nuclear magnetic resonance experiments have been used to monitor the kinetics of hydrolysis and condensation reactions between water and FDTS. Light scattering experiments show that when hydrolyzed FDTS concentrations reach a critical concentration, there is a burst of nucleation to form high concentrations of spherical agglomerates. Atomic force microscopy results show that the agglomerates then deposit on substrate surfaces. Deposition conditions leading to monolayer formation involve using deposition times that are short relative to the induction time for agglomeration. After deposition, inverse micelles can be converted into lamellar or monolayer structures with appropriate heat treatments if surface concentrations are relatively low.

BUNKER,BRUCE C.; CARPICK,ROBERT W.; ASSINK,ROGER A.; THOMAS,MICHAEL L.; HANKINS,MATTHEW G.; VOIGT,JAMES A.; SIPOLA,DIANA L.; DE BOER,MAARTEN P.; GULLEY,GERALD L.

2000-04-17

329

Techniques for mapping the types, volumes, and distribution of clays in petroleum reservoirs and for determining their effects on oil production. Final report  

SciTech Connect

This report presents the results of correlation of log signatures with information on distribution of the types and volumes of clays in sandstone pore spaces determined from detailed CT-scan, XRD, SEM, and thin section analyses of core samples from three sandstone reservoirs. The log signatures are then analyzed to determine if suitable mathematical/statistical parameter(s) could be calculated from the logs to determine their effects on permeability and oil production. The variability measures obtained from power spectral analysis of permeability and wireline log data in clayey formations have been correlated with oil production from two oil fields. Compared with the conventional measures of permeability variations like the Dykstra-Parsons coefficients, the new measure appears to correlate better with oil production.

Sharma, B.

1993-05-01

330

Techniques for mapping the types, volumes, and distribution of clays in petroleum reservoirs and for determining their effects on oil production  

SciTech Connect

This report presents the results of correlation of log signatures with information on distribution of the types and volumes of clays in sandstone pore spaces determined from detailed CT-scan, XRD, SEM, and thin section analyses of core samples from three sandstone reservoirs. The log signatures are then analyzed to determine if suitable mathematical/statistical parameter(s) could be calculated from the logs to determine their effects on permeability and oil production. The variability measures obtained from power spectral analysis of permeability and wireline log data in clayey formations have been correlated with oil production from two oil fields. Compared with the conventional measures of permeability variations like the Dykstra-Parsons coefficients, the new measure appears to correlate better with oil production.

Sharma, B.

1993-05-01

331

The large-scale production of carbon nanotubes in a nano-agglomerate fluidized-bed reactor  

Microsoft Academic Search

Carbon nanotubes (CNTs) produced by catalytic chemical vapor deposition (CCVD) can be formed into loose agglomerates that can be fluidized during the growth process. This provides a way to prepare high-quality CNTs on a large scale at low cost in a nano-agglomerate fluidized-bed reactor (NAFBR). With the present fluidized-bed reactor design and catalyst preparation, 50 kg\\/day of carbon materials was

Yao Wang; Fei Wei; Guohua Luo; Hao Yu; Guangsheng Gu

2002-01-01

332

Application of laser backscattering for monitoring of palm oil crystallisation from melt  

NASA Astrophysics Data System (ADS)

The evolution of chord length distributions of crystals during the isothermal crystallisation and post-crystallisation remelting of palm oil was monitored in a stirred, jacketed glass vessel using the Focused Beam Reflectance Measurement (FBRM) instrument probe at isothermal temperatures between 24 and 32 °C. Results show that the mean crystal chord length increases with increasing isothermal temperature up to 26 °C but then decreases again at higher temperatures. This appears to be due to the greater susceptibility for crystals formed at higher temperatures to break up into smaller fragments. An induction time is clearly evident in all experiments and this increases with temperature as expected. Post-crystallisation remelting experiments showed evidence of deagglomeration and disintegration of solid entities. This is thought to be due to the melting of bridges that hold crystals together in agglomerates. This is one of the first studies to demonstrate that the FBRM technique is an efficient in situ monitoring tool, capable of providing valuable information regarding the dynamic evolution of particle population and size as well as the detection of events related to crystallisation and melting of palm oil.

Hishamuddin, Elina; Stapley, Andrew G. F.; Nagy, Zoltan K.

2011-11-01

333

Peppermint Oil  

MedlinePLUS

... Read our disclaimer about external links Menu Peppermint Oil Common Name: peppermint oil Latin Name: Mentha x piperita peppermint.jpg © Steven ... This fact sheet provides basic information about peppermint oil—common names, what the science says, potential side ...

334

Oil Shale - An Impending Energy Source  

Microsoft Academic Search

The characteristics of the Green River Formation oil-shale deposits are briefly reviewed to recall location, extent, accessibility, and richness of the shales. Retorting techniques developed by the Bureau of Mines, Union Oil Company, or the Oil Shale Corporation are suggested to be the most likely candidates for early use in recovering the energy values in the shale. An alternative technique,

Glenn Cook

1972-01-01

335

Dust agglomeration  

NASA Technical Reports Server (NTRS)

John Marshall, an investigator at Ames Research Center and a principal investigator in the microgravity fluid physics program, is studying the adhesion and cohesion of particles in order to shed light on how granular systems behave. These systems include everything from giant dust clouds that form planets to tiny compressed pellets, such as the ones you swallow as tablets. This knowledge should help us control the grains, dust, and powders that we encounter or use on a daily basis. Marshall investigated electrostatic charge in microgravity on the first and second U.S. Microgravity Laboratory shuttle missions to see how grains aggregate, or stick together. With gravity's effects eliminated on orbit, Marshall found that the grains of sand that behaved ever so freely on Earth now behaved like flour. They would just glom together in clumps and were quite difficult to disperse. That led to an understanding of the prevalence of the electrostatic forces. The granules wanted to aggregate as little chains, like little hairs, and stack end to end. Some of the chains had 20 or 30 grains. This phenomenon indicated that another force, what Marshall believes to be an electrostatic dipole, was at work.(The diagram on the right emphasizes the aggregating particles in the photo on the left, taken during the USML-2 mission in 1995.)

2000-01-01

336

Oil Spill!  

ERIC Educational Resources Information Center

An oil spill occurs somewhere in the world almost every day of the year, and the consequences can be devastating. In this month's column, students explore the effects of oil spills on plants, animals, and the environment and investigate oil spill clean-up methods through a simulated oil spill. The activities described in this article give students…

Ansberry, Karen Rohrich; Morgan, Emily

2005-01-01

337

Motor oil  

NSDL National Science Digital Library

Motor oil can be recycled and reused, cutting down on our foreign oil dependence. It can also contaminate drinking water and harm beach shore sand, as well as birds. Birds covered in oil cannot fly again until all the oil is washed off.

N/A N/A (None;)

2007-02-11

338

Inoculation of Bacillus sphaericus UPMB-10 to Young Oil Palm and Measurement of Its Uptake of Fixed Nitrogen Using the 15N Isotope Dilution Technique  

PubMed Central

There are increasing applications of diazotrophic rhizobacteria in the sustainable agriculture system. A field experiment on young immature oil palm was conducted to quantify the uptake of N derived from N2 fixation by the diazotroph Bacillus sphaericus strain UPMB-10, using the 15N isotope dilution method. Eight months after 15N application, young immature oil palms that received 67% of standard N fertilizer application together with B. sphaericus inoculation had significantly lower 15N enrichment than uninoculated palms that received similar N fertilizers. The dilution of labeled N served as a marker for the occurrence of biological N2 fixation. The proportion of N uptake that was derived from the atmosphere was estimated as 63% on the whole plant basis. The inoculation process increased the N and dry matter yields of the palm leaflets and rachis significantly. Field planting of young, immature oil palm in soil inoculated with B. sphaericus UPMB-10 might mitigate inorganic fertilizer-N application through supplementation by biological nitrogen fixation. This could be a new and important source of nitrogen biofertilizer in the early phase of oil palm cultivation in the field. PMID:22446306

Zakry, Fitri Abdul Aziz; Shamsuddin, Zulkifli H.; Rahim, Khairuddin Abdul; Zakaria, Zin Zawawi; Rahim, Anuar Abdul

2012-01-01

339

Inoculation of Bacillus sphaericus UPMB-10 to young oil palm and measurement of its uptake of fixed nitrogen using the ¹?N isotope dilution technique.  

PubMed

There are increasing applications of diazotrophic rhizobacteria in the sustainable agriculture system. A field experiment on young immature oil palm was conducted to quantify the uptake of N derived from N? fixation by the diazotroph Bacillus sphaericus strain UPMB-10, using the ¹?N isotope dilution method. Eight months after ¹?N application, young immature oil palms that received 67% of standard N fertilizer application together with B. sphaericus inoculation had significantly lower ¹?N enrichment than uninoculated palms that received similar N fertilizers. The dilution of labeled N served as a marker for the occurrence of biological N? fixation. The proportion of N uptake that was derived from the atmosphere was estimated as 63% on the whole plant basis. The inoculation process increased the N and dry matter yields of the palm leaflets and rachis significantly. Field planting of young, immature oil palm in soil inoculated with B. sphaericus UPMB-10 might mitigate inorganic fertilizer-N application through supplementation by biological nitrogen fixation. This could be a new and important source of nitrogen biofertilizer in the early phase of oil palm cultivation in the field. PMID:22446306

Zakry, Fitri Abdul Aziz; Shamsuddin, Zulkifli H; Abdul Rahim, Khairuddin; Zawawi Zakaria, Zin; Abdul Rahim, Anuar

2012-01-01

340

Combining FIPA ACL With DAML+OIL A Case Study Agent Communication with CIA, FIPA ACL and Techniques of the Semantic Web  

E-print Network

Combining FIPA ACL With DAML+OIL ­ A Case Study Agent Communication with CIA, FIPA ACL chan- nels with Java-based event classes. Information within these events is represented in proprietary defined domain of information chunks to which collaborating agents have to be tailored. In order

Biundo, Susanne

341

Reverse micelle synthesis of oxide nanopowders: mechanisms of precipitate formation and agglomeration effects.  

PubMed

We present an analysis of reverse micelle stability in four model systems. The first two systems, composed of unstable microemulsions of isooctane, water, and Na-AOT with additions of either iron sulfate or yttrium nitrate, were used for the synthesis of iron oxide or yttrium oxide powders. These oxide powders were of nanocrystalline character, but with some level of agglomeration that was dependent on calcination temperature and cleaning procedures. Results show that even though the reverse micellar solutions were unstable, nanocrystalline powders with very low levels of agglomeration could be obtained. This effect can be attributed to the protective action of the surfactant on the surfaces of the powders that prevents neck formation until after all the surfactant has volatilized. A striking feature of the IR spectra collected on the iron oxide powders is the absence of peaks in the ~1715 cm(-1) to 1750 cm(-1) region, where absorption due to the symmetric C=O (carbonyl) stretching occurs. The lack of such peaks strongly suggests the carbonyl group is no longer free, but is actively participating in the surfactant-precipitate interaction. The final two microemulsion systems, containing CTAB as the surfactant, showed that loss of control of the reverse micelle synthesis process can easily occur when the amount of salt in the water domains exceeds a critical concentration. Both model systems eventually resulted in agglomerated powders of broad size distributions or particles that were large compared to the sizes of the reverse micelles, consistent with the notion that the microemulsions were not stable and the powders were precipitated in an uncontrolled fashion. This has implications for the synthesis of nanopowders by reverse micelle synthesis and provides a benchmark for process control if powders of the highest quality are desired. PMID:23906861

Graeve, Olivia A; Fathi, Hoorshad; Kelly, James P; Saterlie, Michael S; Sinha, Kaustav; Rojas-George, Gabriel; Kanakala, Raghunath; Brown, David R; Lopez, Enrique A

2013-10-01

342

Liquid chromatography/mass spectrometry and liquid chromatography/nuclear magnetic resonance as complementary analytical techniques for unambiguous identification of polymethoxylated flavones in residues from molecular distillation of orange peel oils (Citrus sinensis).  

PubMed

Liquid chromatography/mass spectrometry and liquid chromatography/nuclear magnetic resonance techniques with ultraviolet/diode array detection were used as complementary analytical tools for the reliable identification of polymethoxylated flavones in residues from molecular distillation of cold-pressed peel oils of Citrus sinensis. After development of a liquid chromatographic separation procedure, the presence of several polymethoxy flavones such as sinensetin, nobiletin, tangeretin, quercetogetin, heptamethoxyflavone, and other derivatives was unambiguously confirmed. In addition, proceranone, an acetylated tetranortriterpenoid with limonoid structure, was identified for the first time in citrus. PMID:16417279

Weber, Berthold; Hartmann, Beate; Stöckigt, Detlef; Schreiber, Klaus; Roloff, Michael; Bertram, Heinz-Jürgen; Schmidt, Claus O

2006-01-25

343

Influence of oxalic acid on the agglomeration process and total soda content in precipitated Al(OH) 3  

NASA Astrophysics Data System (ADS)

Decomposition of caustic soda solutions is an important part of Bayer process for alumina production. The physico-chemical properties of precipitated Al(OH) 3 are dependent on several processes that take place simultaneously during the decomposition process and they are: nucleation, agglomeration and Al(OH) 3 crystals. An important industrial requirement is increase of Al(OH) 3 crystal grain size, and hence agglomeration and growth of Al(OH) 3 crystals become important processes and they enable increase of particle size. The influence of oxalic acid concentration on the agglomeration process and total soda content in precipitated Al(OH) 3 at different temperatures and caustic soda concentrations has been investigated. The results have shown that the agglomeration process is increased with increase of temperature and decrease of caustic soda concentration. Total soda content in precipitated Al(OH) 3 is changed in the same way. Besides, agglomeration process of Al(OH) 3 particles is favored in the presence of oxalic acid.

Nikoli?, I.; Blec?i?, D.; Blagojevi?, N.; Radmilovi?, V.; Kovac?evi?, K.

2003-05-01

344

Engine bearing oil film thickness measurement and oil rheologh  

SciTech Connect

An American Society for Testing and Materials (ASTM) Task Force was formed in 1984 to: (1) establish a series of reference oils, (2) measure the minimum bearing oil film thicknesses provided by the oils in fired engine, and (3) interpret the results in terms of oil rheological properties. Minimum oil film thickness (MOFT) measurement and analysis techniques using a capacitance method were developed. At steady-state operating conditions, laboratories evaluated a matrix of eighteen monograde and multigrade oils, blended with four widely-used viscosity index improves (VIIs). Analyses showed increasingly better correlations between MOFTs and viscosities of both single grade and multigrade oils as temperatures and shear rates used to calculate viscosities more-closely approximated in-bearing conditions.

Cryvoff, S.A.; Spearot, J.A.; Bates, T.W.

1990-01-01

345

Sonic enhanced ash agglomeration and sulfur capture: Quarterly report, October--December 1994  

SciTech Connect

The major objective of the Phase 1 test program is to confirm the feasibility of the MTCI bimodal particle size approach to enhance particulate control by acoustic ash agglomeration. An ancillary objective of the Phase 1 effort is to demonstrate and confirm the feasibility of an acoustic field to enhance sulfur capture by increasing sorbent reactivity. The program will demonstrate the effectiveness of a unique approach which uses a bimodal distribution composed of large sorbent particles and fine fly ash particles to enhance ash agglomeration and sulfur capture at conditions found in direct coal-fired turbines. The work will extend the concept from the demonstration of feasibility (Phase 1), through proof-of-concept (Phase 2) to the construction (Phase 3) of a coal-fired pulsed combustor with in-furnace sorbent injection. In view of the potentially large repowering market in the US, several possible configurations were formulated and evaluated for application to the repowering market. Based on discussions between the DOE/METC team members and MTCI staff; seven different configuration were proposed for further evaluation. The technical and market issues associated with each of these configurations were identified and summarized. An initial system simulation test for the system operating at inlet air temperatures of 700--800 F as for a gas turbine application was conducted, indicating that acoustic performance can be further improved by modifying gas injectors. Development of the advanced vortex aerovalve continued.

NONE

1995-01-01

346

Water quality studied in areas of unconventional oil and gas development, including areas where hydraulic fracturing techniques are used, in the United States  

USGS Publications Warehouse

The U.S. Geological Survey (USGS) John Wesley Powell Center for Analysis and Synthesis is hosting an interdisciplinary working group of USGS scientists to conduct a temporal and spatial analysis of surface-water and groundwater quality in areas of unconventional oil and gas development. The analysis uses existing national and regional datasets to describe water quality, evaluate water-quality changes over time where there are sufficient data, and evaluate spatial and temporal data gaps.

Susong, David D.; Gallegos, Tanya J.; Oelsner, Gretchen P.

2012-01-01

347

Application of solid phase-microextraction (SPME) and electronic nose techniques to differentiate volatiles of sesame oils prepared with diverse roasting conditions.  

PubMed

Headspace volatiles of sesame oil (SO) from sesame seeds roasted at 9 different conditions were analyzed by a combination of solid phase microextraction (SPME)-gas chromatography/mass spectrometry (GC/MS), electronic nose/metal oxide sensors (MOS), and electronic nose/MS. As roasting temperature increased from 213 to 247 °C, total headspace volatiles and pyrazines increased significantly (P < 0.05). Pyrazines were major volatiles in SO and furans, thiazoles, aldehydes, and alcohols were also detected. Roasting temperature was more discrimination factor than roasting time for the volatiles in SO through the principal component analysis (PCA) of SPME-GC/MS, electronic nose/MOS, and electronic nose/MS. Electronic nose/MS showed that ion fragment 52, 76, 53, and 51 amu played important roles in discriminating volatiles in SO from roasted sesame seeds, which are the major ion fragments from pyrazines, furans, and furfurals. SO roasted at 213, 230, and 247 °C were clearly differentiated from each other on the base of volatile distribution by SPME-GC/MS, electronic nose/MOS, and electronic nose/MS analyses. Practical Application: The results of this study are ready to apply for the discriminating samples using a combinational analysis of volatiles. Not only vegetable oils prepared from roasting process but also any food sample possessing volatiles could be targets for the SPME-GC/MS and electronic nose assays. Contents and types of pyrazines in sesame seed oil could be used as markers to track down the degree of roasting and oxidation during oil preparation. PMID:21535659

Park, Min Hee; Jeong, Min Kyu; Yeo, JuDong; Son, Hee-Jin; Lim, Chae-Lan; Hong, Eun Jeung; Noh, Bong-Soo; Lee, JaeHwan

2011-01-01

348

Increased oil production and reserves utilizing secondary/tertiary recovery techniques on small reservoirs in the Paradox basin, Utah. Annual report  

SciTech Connect

The Paradox basin of Utah, Colorado, and Arizona contains nearly 100 small oil fields producing from carbonate buildups or mounds within the Pennsylvanian (Desmoinesian) Paradox Formation. These fields typically have one to four wells with primary production ranging from 700,000 to 2,000,000 barrels of oil per field at a 15 to 20% recovery rate. At least 200 million barrels of oil is at risk of being unrecovered in these small fields because of inefficient recovery practices and undrained heterogeneous reservoirs. Five fields (Anasazi, mule, Blue Hogan, heron North, and Runway) within the Navajo Nation of southeastern utah are being evaluated for waterflood or carbon-dioxide-miscible flood projects based upon geological characterization and reservoir modeling. The results can be applied to other fields in the Paradox basin and the Rocky Mountain region, the Michigan and Illinois basins, and the Midcontinent. The reservoir engineering component of the work completed to date included analysis of production data and well tests, comprehensive laboratory programs, and preliminary mechanistic reservoir simulation studies. A comprehensive fluid property characterization program was completed. Mechanistic reservoir production performance simulation studies were also completed.

Chidsey, T.C. Jr.

1997-02-01

349

Study on transfer-free graphene synthesis process utilizing spontaneous agglomeration of catalytic Ni and Co metals  

NASA Astrophysics Data System (ADS)

Transfer-free graphene synthesis process utilizing metal agglomeration phenomena was investigated by using carbon films deposited on Ni or Co catalyst metals on SiO2/Si substrates. As a result of metal agglomeration at high temperatures, multilayer graphene films appeared to be formed directly on SiO2 films. The microscopic Raman mapping study revealed that graphene films were preferentially synthesized around areas where metal films disappeared at an early stage of agglomeration, and that they finally covered almost the whole surface. It was also found that the synthesized graphene films tended to have better structural qualities and lower layer numbers with the increase in the starting metal thicknesses regardless of the kinds of catalyst metals. Raman study also showed that they had good two-dimensional uniformity in the structural quality.

Miyoshi, Makoto; Mizuno, Masaya; Banno, Kazuya; Kubo, Toshiharu; Egawa, Takashi; Soga, Tetsuo

2015-01-01

350

Simple Techniques For Assessing Impacts Of Oil And Gas Operations On Public Lands: A Field Evaluation Of A Photoionization Detector (PID) At A Condensate Release Site, Padre Island National Seashore, Texas  

USGS Publications Warehouse

Simple, cost-effective techniques are needed for land managers to assess the environmental impacts of oil and gas production activities on public lands, so that sites may be prioritized for remediation or for further, more formal assessment. Field-portable instruments provide real-time data and allow the field investigator to extend an assessment beyond simply locating and mapping obvious disturbances. Field investigators can examine sites for the presence of hydrocarbons in the subsurface using a soil auger and a photoionization detector (PID). The PID measures volatile organic compounds (VOC) in soil gases. This allows detection of hydrocarbons in the shallow subsurface near areas of obvious oil-stained soils, oil in pits, or dead vegetation. Remnants of a condensate release occur in sandy soils at a production site on the Padre Island National Seashore in south Texas. Dead vegetation had been observed by National Park Service personnel in the release area several years prior to our visit. The site is located several miles south of the Malaquite Beach Campground. In early 2001, we sampled soil gases for VOCs in the area believed to have received the condensate. Our purpose in this investigation was: 1) to establish what sampling techniques might be effective in sandy soils with a shallow water and contrast them with techniques used in an earlier study; and 2) delineate the probable area of condensate release. Our field results show that sealing the auger hole with a clear, rigid plastic tube capped at the top end and sampling the soil gas through a small hole in the cap increases the soil VOC gas signature, compared to sampling soil gases in the bottom of an open hole. This sealed-tube sampling method increases the contrast between the VOC levels within a contaminated area and adjacent background areas. The tube allows the PID air pump to draw soil gas from the volume of soil surrounding the open hole below the tube in a zone less influenced by atmospheric air. In an open hole, the VOC readings seem to be strongly dependent on the degree of diffusion and advection of soil gas VOCs into the open hole from the surrounding soil, a process that may vary with soil and wind conditions. Making measurements with the sealed hole does take some additional time (4-7 minutes after the hole is augered) compared to the open-hole technique (1-2 minutes). We used the rigid-plastic tube technique to survey for soil gas VOCs across the entire site, less than ? acre. Condensate has impacted at least 0.28 acres. The impacted area may extend northwest of the surveyed area.

Otton, James K.; Zielinski, Robert A.

2001-01-01

351

Fluorescence characteristics of oil during the Deepwater Horizon oil spill  

Microsoft Academic Search

Emergency responders, agencies and researchers have tracked oil spilled during the Deepwater Horizon event using a number of techniques, including fluorescence, particle size and chemical analyses. Even though current protocols call for the use of in situ fluorometers to detect the presence of oil throughout the water column, these fluorometers have not been designed to yield information on changes in

P. G. Coble; R. N. Conmy; M. Wood; K. Lee; P. Kepkay; Z. Li

2010-01-01

352

SAMPLING OIL-WATER MIXTURES AT OHMSETT (OIL AND HAZARDOUS MATERIALS SIMULATED ENVIRONMENTAL TEST TANK)  

EPA Science Inventory

The report describes procedures developed at the Oil and Hazardous Material Simulated Environmental Test Tank (OHMSETT) for sampling oil and water mixtures. Two procedures for sampling in containers are discussed: grab and stratified sampling. Both of these techniques require str...

353

LEVEL OF SOMATIC DEVELOPMENT OF CHILDREN AGED SIX YEARS FROM AN URBAN AGGLOMERATION IN POLAND WITH RESPECT TO SELECTED ENVIRONMENTAL CONDITIONS.  

PubMed

Summary The aim of this study was to assess the somatic development of children from an urban agglomeration in Poland at the end of preschool education and the beginning of primary education with respect to selected socioeconomic and educational conditions. Data were collected for 742 children from selected Warsaw kindergartens in spring 2011 and 2012. Their mean age was 5.84±0.31 years. The sex categories were equal: 371 boys and 371 girls. Kindergartens chosen for the study constituted a representative sample. The diagnostic survey method (questionnaire technique) was used to assess the selected environmental conditions of development in the participating children. Body height and the sum of six skin folds (over the biceps, over the triceps, under the scapula, on the abdomen, over the wing of ilium and on the calf) were chosen from the assessed anthropometric parameters for the purpose of determining somatic development of study participants. The obtained data were analysed using selected descriptive statistics methods (including cluster analysis), data standardization (normalization by mean values and SD) and the chi-squared test. The results showed certain relationships between the selected parameters of somatic development and family living conditions. These relationships involved differences between individual clusters depending on given living conditions and were most prominent for mother's education, for which variable differences between clusters were found for both sexes. The somatic build of boys (including body height and body adiposity) also differed depending on the number of offspring in the family, while the somatic build of girls differed depending on father's employment and father's education. Furthermore, the obtained results lead to the conclusion that the total number of differences between the analysed clusters was relatively low. This indicates that the biological effects of social stratification tend to diminish in the environment of an urban agglomeration. PMID:25392125

Trzci?ska, Dorota; Tabor, Piotr; Olszewska, El?bieta

2014-11-13

354

Increased oil production and reserves utilizing secondary/tertiary recovery techniques on small reservoirs in the Paradox basin, Utah. Annual report, February 9, 1996--February 8, 1997  

SciTech Connect

The Paradox basin of Utah, Colorado, and Arizona contains nearly 100 small oil fields producing from carbonate buildups or mounds within the Pennsylvanian (Desmoinesian) Paradox Formation. These fields typically have one to four wells with primary production ranging from 700,000 to 2,000,000 barrels of oil per field at a 15 to 20% recovery rate. At least 200 million barrels of oil is at risk of being unrecovered in these small fields because of inefficient recovery practices and undrained heterogeneous reservoirs. Five fields (Anasazi, Mule, Blue Hogan, Heron North, and Runway) within the Navajo Nation of southeastern Utah are being evaluated for waterflood or carbon-dioxide-miscible flood projects based upon geological characterization and reservoir modeling. The results can be applied to other fields in the Paradox basin and the Rocky Mountain region, the Michigan and Illinois basins, and the Midcontinent. The Anasazi field was selected for the initial geostatistical modeling and reservoir simulation. A compositional simulation approach is being used to model primary depletion, waterflood, and CO{sub 2}-flood processes. During this second year of the project, team members performed the following reservoir-engineering analysis of Anasazi field: (1) relative permeability measurements of the supra-mound and mound-core intervals, (2) completion of geologic model development of the Anasazi reservoir units for use in reservoir simulation studies including completion of a series of one-dimensional, carbon dioxide-displacement simulations to analyze the carbon dioxide-displacement mechanism that could operate in the Paradox basin system of reservoirs, and (3) completion of the first phase of the full-field, three-dimensional Anasazi reservoir simulation model, and the start of the history matching and reservoir performance prediction phase of the simulation study.

Chidsey, T.C. Jr.

1997-08-01

355

Bed material agglomeration during fluidized bed combustion. Technical progress report, April 1, 1993--June 30, 1993  

SciTech Connect

A survey of agglomeration and deposit formation in industrial fluidized bed boilers indicate that several facilities are experiencing some form of bed material agglomeration. Deposit formation was reported at nine sites with these deposits being, found most commonly at coal feed locations and in cyclones. Deposit and agglomerate samples have been received from four units. Our analyses of the cyclone deposits indicate they are primarily composed of an iron-aluminosilicate material. The bulk of the deposit is about 30 wt % SiO{sub 2}), 18 wt % Al{sub 2}O{sub 3}, and 30 to 33 wt % Fe{sub 2}O{sub 3}. Titanium is also present between 3 and 4 wt %. All the iron in the deposit is now in the Fe+3 state, but there is evidence that at the time of deposit formation it was in the Fe+2 state. The atomic structure of the bulk of the deposit is that of the spinel mineral maghemite. In nature, this is a rare mineral which forms by the oxidation of the mineral magnetite. Magnetite contains iron in both the +2 and +3 states and can incorporate titanium into its structure at low oxygen fugacities. The relatively high titanium content of the deposit suggests that it may have originally been magnetite (formed at a low oxygen fugacity), but was later oxidized to maghemite under higher oxygen fugacities. We have hypothesized that the cause of deposit formation was most likely interaction of iron, as a flux (in a reduced form), with aluminosilicate materials (clays). The iron probably originated as pyrite or iron sulfides in the feed. It also appears the quench water plays a role in enhancing, the deposit formation in the cyclones. We have hypothesized that the high iron content of solids in the sour quench water probably did not play a role in deposit formation; although, the high water vapor pressure may have had an effect on the viscosity of the material. The alkalic elements, Na and K, probably played only a minor role in deposit formation.

Brown, R.C.; Dawson, M.R.; Noble, S.D.

1993-07-01

356

Processing-related fracture origins. III. Differential sintering of ZrO2 agglomerates in Al2O3\\/ZrO2 composite  

Microsoft Academic Search

Large, hard ZrO2 agglomerates remained in an Al2O3\\/ZrO2 composite suspension after inefficient ball-milling. The ZrO2 agglomerates shrank away from the consolidated Al2O3\\/ZrO2 powder matrix during sintering, producing cracklike voids which were responsible for strength degradation.

F. F. Lange; B. I. Davis; I. A. AKSAY

1983-01-01

357

In-Situ Burning of Spilled Oil.  

ERIC Educational Resources Information Center

Reviews in-situ burning with particular emphasis on how it can be applied in water-related oil spill situations. Presents and discusses the use of nomograms and development of techniques cited for safe and effective ignition and controlled burning of spilled oil. Includes representative oil spill scenarios and possible responses. (15 references)…

Allen, Alan A.

1991-01-01

358

Using a non-invasive technique in nutrition: synchrotron radiation infrared microspectroscopy spectroscopic characterization of oil seeds treated with different processing conditions on molecular spectral factors influencing nutrient delivery.  

PubMed

Non-invasive techniques are a key to study nutrition and structure interaction. Fourier transform infrared microspectroscopy coupled with a synchrotron radiation source (SR-IMS) is a rapid, non-invasive, and non-destructive bioanalytical technique. To understand internal structure changes in relation to nutrient availability in oil seed processing is vital to find optimal processing conditions. The objective of this study was to use a synchrotron-based bioanalytical technique SR-IMS as a non-invasive and non-destructive tool to study the effects of heat-processing methods and oil seed canola type on modeled protein structure based on spectral data within intact tissue that were randomly selected and quantify the relationship between the modeled protein structure and protein nutrient supply to ruminants. The results showed that the moisture heat-related processing significantly changed (p<0.05) modeled protein structures compared to the raw canola (control) and those processing by dry heating. The moisture heating increased (p<0.05) spectral intensities of amide I, amide II, ?-helices, and ?-sheets but decreased (p<0.05) the ratio of modeled ?-helices to ?-sheet spectral intensity. There was no difference (p>0.05) in the protein spectral profile between the raw and dry-heated canola tissue and between yellow- and brown-type canola tissue. The results indicated that different heat processing methods have different impacts on the protein inherent structure. The protein intrinsic structure in canola seed tissue was more sensitive and more response to the moisture heating in comparison to the dry heating. These changes are expected to be related to the nutritive value. However, the current study is based on limited samples, and more large-scale studies are needed to confirm our findings. PMID:24920208

Zhang, Xuewei; Yu, Peiqiang

2014-07-01

359

A model for agglomeration in bio-fuel fired fluidized bed  

NASA Astrophysics Data System (ADS)

A mathematical model has been developed to describe the agglomeration process in bio-fuel fired fluidized bed combustor. Based on the balance mechanism of the adhesive force caused by liquid bonding between two particles and the breaking force induced by bubbles in the fluidized bed, the model considers modified Urbain model and chemical equilibrium calculations using FactSage modeling. This model prediction accounts for the evolvement of the adhesive and breaking forces, and clearly demonstrates that the different composition of ash, the increasing liquid phase matter and the fluidization velocity cause defluidization in fluidized bed. In this model, it is the first time to hypothesize that the bonding stress between two particles is proportional to mass fraction of liquid phase and inversely proportional to the diameter of particles and viscosity of liquid phase. The defluidization time calculated by this model shows good agreement with that from the experimental data.

Li, Shiyuan; Shang, Linlin; Teng, Haipeng; Lu, Qinggang

2010-10-01

360

Megacities and large urban agglomerations in the coastal zone: interactions between atmosphere, land, and marine ecosystems.  

PubMed

Megacities are not only important drivers for socio-economic development but also sources of environmental challenges. Many megacities and large urban agglomerations are located in the coastal zone where land, atmosphere, and ocean meet, posing multiple environmental challenges which we consider here. The atmospheric flow around megacities is complicated by urban heat island effects and topographic flows and sea breezes and influences air pollution and human health. The outflow of polluted air over the ocean perturbs biogeochemical processes. Contaminant inputs can damage downstream coastal zone ecosystem function and resources including fisheries, induce harmful algal blooms and feedback to the atmosphere via marine emissions. The scale of influence of megacities in the coastal zone is hundreds to thousands of kilometers in the atmosphere and tens to hundreds of kilometers in the ocean. We list research needs to further our understanding of coastal megacities with the ultimate aim to improve their environmental management. PMID:23076973

von Glasow, Roland; Jickells, Tim D; Baklanov, Alexander; Carmichael, Gregory R; Church, Tom M; Gallardo, Laura; Hughes, Claire; Kanakidou, Maria; Liss, Peter S; Mee, Laurence; Raine, Robin; Ramachandran, Purvaja; Ramesh, R; Sundseth, Kyrre; Tsunogai, Urumu; Uematsu, Mitsuo; Zhu, Tong

2013-02-01

361

Complexometric determination of aluminium in iron ore, sinter, concentrates and agglomerates.  

PubMed

A method for the complexometric determination of aluminium in iron ore, sinter, concentrates and agglomerates encountered in international trade is described. The sample is fused in a zirconium crucible with a mixed flux of sodium carbonate and sodium peroxide. The fused mass is completely soluble in hydrochloric acid. The R(2)O(3) oxides are then precipitated with ammonia and redissolved in hydrochloric acid. Elements such as iron, titanium and zirconium are separated from aluminium by solvent extraction with cupferron and chloroform. After removal of traces of organic matter from the aqueous phase, the solution is treated with an excess of EDTA, which is then back-titrated with zinc solution (Xylenol Orange as indicator). Addition of ammonium fluoride then releases EDTA equivalent to the aluminium and this is titrated with zinc solution. The method is rapid. The precision and accuracy are excellent, and the results comparable with those obtained by the referee method. PMID:18962398

Bhargava, O P

1979-02-01

362

THE PHYSICS OF PROTOPLANETESIMAL DUST AGGLOMERATES. VI. EROSION OF LARGE AGGREGATES AS A SOURCE OF MICROMETER-SIZED PARTICLES  

SciTech Connect

Observed protoplanetary disks consist of a large amount of micrometer-sized particles. Dullemond and Dominik pointed out for the first time the difficulty in explaining the strong mid-infrared excess of classical T Tauri stars without any dust-retention mechanisms. Because high relative velocities in between micrometer-sized and macroscopic particles exist in protoplanetary disks, we present experimental results on the erosion of macroscopic agglomerates consisting of micrometer-sized spherical particles via the impact of micrometer-sized particles. We find that after an initial phase, in which an impacting particle erodes up to 10 particles of an agglomerate, the impacting particles compress the agglomerate's surface, which partly passivates the agglomerates against erosion. Due to this effect, the erosion halts for impact velocities up to {approx}30 m s{sup -1} within our error bars. For higher velocities, the erosion is reduced by an order of magnitude. This outcome is explained and confirmed by a numerical model. In a next step, we build an analytical disk model and implement the experimentally found erosive effect. The model shows that erosion is a strong source of micrometer-sized particles in a protoplanetary disk. Finally, we use the stationary solution of this model to explain the amount of micrometer-sized particles in the observational infrared data of Furlan et al.

Schraepler, Rainer; Blum, Juergen, E-mail: r.schraepler@tu-bs.de [Institut fuer Geophysik und extraterrestrische Physik, University of Braunschweig, Mendelssohnstr. 3, D-38106 Braunschweig (Germany)

2011-06-20

363

A systematic evaluation of agglomeration of Ag and TiO2 nanoparticles under freshwater relevant conditions.  

PubMed

This study aims to investigate effects of freshwater components in order to predict agglomeration behavior of silver nanoparticles coated with citrate (AgNP-Cit), polyvinylpyrrolidone (AgNP-PVP), and of TiO2 nanoparticles. Agglomeration studies were conducted in various media based on combinations of ions, natural organic matter (humic, fulvic acid) and surfactants (sodium dodecyl sulfate, alkyl ethoxylate), at a constant ionic strength of 10 mM over time for up to 1 week. Agglomeration level of AgNP-Cit and TiO2 was mostly dependent on the concentration of Ca(2+) in media, and their size strongly increased to micrometer scale over 1 week. However, AgNP-Cit and TiO2 were stabilized to particle size around 500 nm in the presence of NOM, surfactants and carbonate over 1 week. AgNP-PVP maintained their original size in all media except in the presence of Mg(2+) ions which led to significant agglomeration. Behavior of these engineered nanoparticles was similar in a natural freshwater medium. PMID:25000117

Topuz, Emel; Sigg, Laura; Talinli, Ilhan

2014-10-01

364

Sonic enhanced ash agglomeration and sulfur capture. [Thirteenth quarterly] technical progress report, [June 29, 1992--September 27, 1992  

SciTech Connect

The Sonic Enhanced Ash Agglomeration and Sulfur Capture program focuses upon the application of an MTCI proprietary invention (Invention Disclosure filed) for simultaneously enhancing sulfur capture and particulate agglomeration of the combustor effluent. This application can be adapted as either a ``hot flue gas cleanup`` subsystem for the current concepts for combustor islands or as an alternative primary pulse combustor island in which slagging, sulfur capture, particulate agglomeration and control, and alkali gettering as well as NO{sub x} control processes become an integral part of the pulse combustion process. The goal of the program is to support the DOE mission in developing coal-fired combustion gas turbines. In particular, the MTCI proprietary process for bimodal ash agglomeration and simultaneous sulfur capture will be evaluated and developed. The technology embodiment of the invention provides for the use of standard grind, moderately beneficiated coal and WEM for firing the gas turbine with efficient sulfur capture and particulate emission control upstream of the turbine. The process also accommodates injection of alkali gettering material if necessary. This is aimed at utilization of relatively inexpensive coal fuels, thus realizing the primary benefit being sought by direct firing of coal in such gas turbine systems.

Not Available

1992-12-31

365

Airborne optical detection of oil on water.  

NASA Technical Reports Server (NTRS)

Airborne measurements were made over controlled oil-spill test sites to evaluate various techniques, utilizing reflected sunlight, for detecting oil on water. The results of these measurements show that (1) maximum contrast between oil and water is in the UV and red portions of the spectrum; (2) minimum contrast is in the blue-green; (3) differential polarization appears to be a very promising technique; (4) no characteristic absorption bands, which would permit one oil to be distinguished from another, were discovered in the spectral regions measured; (5) sky conditions greatly influence the contrast between oil and water; and (6) highest contrast was achieved under overcast sky conditions.

Millard, J. P.; Arvesen, J. C.

1972-01-01

366

Bio-refinery of orange peels waste: A new concept based on integrated green and solvent free extraction processes using ultrasound and microwave techniques to obtain essential oil, polyphenols and pectin.  

PubMed

In this study, extraction of essential oil, polyphenols and pectin from orange peel has been optimized using microwave and ultrasound technology without adding any solvent but only "in situ" water which was recycled and used as solvent. The essential oil extraction performed by Microwave Hydrodiffusion and Gravity (MHG) was optimized and compared to steam distillation extraction (SD). No significant changes in yield were noticed: 4.22±0.03% and 4.16±0.05% for MHG and SD, respectively. After extraction of essential oil, residual water of plant obtained after MHG extraction was used as solvent for polyphenols and pectin extraction from MHG residues. Polyphenols extraction was performed by ultrasound-assisted extraction (UAE) and conventional extraction (CE). Response surface methodology (RSM) using central composite designs (CCD) approach was launched to investigate the influence of process variables on the ultrasound-assisted extraction (UAE). The statistical analysis revealed that the optimized conditions of ultrasound power and temperature were 0.956W/cm(2) and 59.83°C giving a polyphenol yield of 50.02mgGA/100gdm. Compared with the conventional extraction (CE), the UAE gave an increase of 30% in TPC yield. Pectin was extracted by conventional and microwave assisted extraction. This technique gives a maximal yield of 24.2% for microwave power of 500W in only 3min whereas conventional extraction gives 18.32% in 120min. Combination of microwave, ultrasound and the recycled "in situ" water of citrus peels allow us to obtain high added values compounds in shorter time and managed to make a closed loop using only natural resources provided by the plant which makes the whole process intensified in term of time and energy saving, cleanliness and reduced waste water. PMID:25435398

Boukroufa, Meryem; Boutekedjiret, Chahrazed; Petigny, Loïc; Rakotomanomana, Njara; Chemat, Farid

2015-05-01

367

HETEROGENEOUS SHALLOW-SHELF CARBONATE BUILDUPS IN THE PARADOX BASIN, UTAH AND COLORADO: TARGETS FOR INCREASED OIL PRODUCTION AND RESERVES USING HORIZONTAL DRILLING TECHNIQUES  

SciTech Connect

The Paradox Basin of Utah, Colorado, Arizona, and New Mexico contains nearly 100 small oil fields producing from carbonate buildups within the Pennsylvanian (Desmoinesian) Paradox Formation. These fields typically have one to 10 wells with primary production ranging from 700,000 to 2,000,000 barrels (111,300-318,000 m{sup 3}) of oil per field and a 15 to 20 percent recovery rate. At least 200 million barrels (31.8 million m{sup 3}) of oil will not be recovered from these small fields because of inefficient recovery practices and undrained heterogeneous reservoirs. Several fields in southeastern Utah and southwestern Colorado are being evaluated as candidates for horizontal drilling and enhanced oil recovery from existing vertical wells based upon geological characterization and reservoir modeling case studies. Geological characterization on a local scale is focused on reservoir heterogeneity, quality, and lateral continuity, as well as possible reservoir compartmentalization, within these fields. This study utilizes representative cores, geophysical logs, and thin sections to characterize and grade each field's potential for drilling horizontal laterals from existing development wells. The results of these studies can be applied to similar fields elsewhere in the Paradox Basin and the Rocky Mountain region, the Michigan and Illinois Basins, and the Midcontinent region. This report covers research activities for the second half of the third project year (October 6, 2002, through April 5, 2003). The primary work included describing and mapping regional facies of the upper Ismay and lower Desert Creek zones of the Paradox Formation in the Blanding sub-basin, Utah. Regional cross sections show the development of ''clean carbonate'' packages that contain all of the productive reservoir facies. These clean carbonates abruptly change laterally into thick anhydrite packages that filled several small intra-shelf basins in the upper Ismay zone. Examination of upper Ismay cores identified seven depositional facies: open marine, middle shelf, inner shelf/tidal flat, bryozoan mounds, phylloid-algal mounds, quartz sand dunes, and anhydritic salinas. Lower Desert Creek facies include open marine, middle shelf, protomounds/collapse breccia, and phylloid-algal mounds. Mapping the upper Ismay zone facies delineates very prospective reservoir trends that contain porous, productive buildups around the anhydrite-filled intra-shelf basins. Facies and reservoir controls imposed by the anhydritic intra-shelf basins should be considered when selecting the optimal location and orientation of any horizontal drilling from known phylloidalgal reservoirs to undrained reserves, as well as identifying new exploration trends. Although intra-shelf basins are not present in the lower Desert Creek zone of the Blanding sub-basin, drilling horizontally along linear shoreline trends could also encounter previously undrilled, porous intervals and buildups. Technology transfer activities consisted of a technical presentation at a Class II Review conference sponsored by the National Energy Technology Laboratory at the Center for Energy and Economic Diversification in Odessa, Texas. The project home page was updated on the Utah Geological Survey Internet web site.

David E. Eby; Thomas C. Chidsey, Jr.; Kevin McClure; Craig D. Morgan

2003-07-01

368

Supercritical fluid extraction of vegetable oil seeds  

Microsoft Academic Search

The extraction of oil from canola seeds using supercritical carbon dioxide was investigated. The basic equations which govern\\u000a the oil extraction from a bed of seeds were derived from first principles. The equations can be solved by standard numerical\\u000a techniques using experimentally determined parameters for the concentration of oil in the solvent in equilibrium with seeds\\u000a having a known oil

N. R. Bulley; M. Fattori; A. Meisen; L. Moyls

1984-01-01

369

Used oil as a fuel oil alternative  

SciTech Connect

In this study, the possibility of using used frying oil as a fuel oil alternative has been investigated. The fuel oil analysis tests applied to the reference fuel oil, used frying oil and its blends with fuel oil, were done according to standard test methods. The experimental results indicated that used frying oil and its blends with fuel oil can be proposed as a possible substitute for fuel oil.

Karaosmanoglu, F.; Beker, U.G. [Istanbul Technical Univ. (Turkey). Chemical Engineering Dept.

1996-09-01

370

Oil Spill  

NSDL National Science Digital Library

In this simulation, learners try to clean up an "oil spill" with different items to understand the challenge scientists face in finding the best materials to clean up large oil spills in nature. Learners test cotton balls, dryer lint, sand, and grass to find out which absorbs the most oil. Then, learners submit their findings and comments online. The web page includes a video interview with a NASA environmental engineer and a link to other resources and activities.

Science, Lawrence H.

2009-01-01

371

Oil Spill  

NSDL National Science Digital Library

This lesson will allow students to explore an important role of environmental engineers: cleaning the environment. Students will learn details about the Exxon Valdez oil spill, which was one of the most publicized and studied environmental tragedies in history. In the accompanying activity, they will try many "engineered" strategies to clean up their own manufactured oil spill and learn the difficulties of dealing with oil released into our waters.

Integrated Teaching And Learning Program

372

Satellite image processing and analyzing for marine oil spills  

Microsoft Academic Search

Oil spills are seriously affecting marine ecosystem and cause political and scientific concern. In order to implement an emergency in case of oil spills, it is necessary to monitor oil spill using remote sensing. Techniques for monitoring oil spills includes optical, microwave, and radar approaches using aircraft or satellites. However, Satellites have wider coverage and lower price. Recent years, with

Ying Li; Shuiming Yu; Long Ma; Yu Liu; Qijun Li

2008-01-01

373

Development of fireside performance indices, Task 7.33, Development of methods to predict agglomeration and deposition in FBCS, Task 7.36, Enhanced air toxics control, Task 7.45  

SciTech Connect

The Energy & Environmental Research Center (EERC) has been developing advanced indices that rank coals according to their fouling and slagging propensity in utility boilers. The indices are based on sophisticated analytical techniques for identifying and quantifying coal inorganics and are useful in predicting the effects of proposed operational changes on ash deposition in coal-fired boilers. These indices are intended to provide an economical way to reduce the amount of full-scale testing needed to determine the best means of minimizing ash-related problems. The successful design and operation of the fluidized-bed combustor requires the ability to control and mitigate ash-related problems. The major ash-related problems in FBC are agglomeration of bed material, ash deposition on heat-transfer surfaces, ash deposition on refractory and uncooled surfaces, corrosion, and erosion. The focus of the Development of Methods to Predict Agglomeration and Deposition in FBCs is on the agglomeration and deposition problems in atmospheric bubbling and circulating beds. The 1990 Clean Air Act Amendments require study of air toxic emissions from coal combustion systems. Since most of the toxic metals present in coal will be in particulate form, a high level of fine-particle control appears to be the best approach to achieving a high level of air toxics control. However, over 50% of mercury and a portion of selenium emissions are in vapor form and are not typically collected in particulate control devices. Therefore, the goal of this project is to develop methods that capture the vapor-phase metals while simultaneously achieving ultrahigh collection efficiency of particulate air toxics.

Zygarlicke, C.J.; Mann, M.D.; Laudal, D.L.; Miller, S.J.

1994-01-01

374

Techniques for Teachers Section  

ERIC Educational Resources Information Center

Includes a simple technique to demonstrate Millikan's oil drop experiment, an environmental studies experiment to measure dissolved oxygen in water samples, and a technique to demonstrate action-reaction. Science materials described are the Pol-A-Star Tomiscope, Nuffield chemistry film loops, air pucks and pH meters. (JR)

Tait, A., Ed.

1973-01-01

375

Increased oil production and reserves from improved completion techniques in the Bluebell Field, Uinta Basin, Utah. Annual report, October 1, 1994--September 30, 1995  

SciTech Connect

The Bluebell field produces from the Tertiary lower Green River and Wasatch Formations of the Uinta Basin, Utah. The productive interval consists of thousands of feet of interbedded fractured clastic and carbonate beds deposited in a fluvial-dominated deltaic lacustrine environment. Wells in the Bluebell field are typically completed by perforating 40 or more beds over 1,000 to 3,000 vertical feet (300-900 m), then applying an acid-fracture stimulation treatment to the entire interval. This completion technique is believed to leave many potentially productive beds damaged and/or untreated, while allowing water-bearing and low-pressure (thief) zones to communicate with the wellbore. Geologic and engineering characterization has been used to define improved completion techniques. The study identified reservoir characteristics of beds that have the greatest long-term production potential.

Allison, M.L.; Morgan, C.D.

1996-05-01

376

In situ spectrometric and chemical measurements of methane emissions from a natural marine hydrocarbon seep field, Coal Oil Point, California: Validation of methane remote sensing techniques  

Microsoft Academic Search

Remote sensing techniques can significantly improve our understanding of the sources and sinks of the important greenhouse gas methane. Field and laboratory studies used spectral and in-situ chemical measurements of geologic methane plumes from natural marine seepage and radiative-transfer calculations to test the feasibility of using NASA's Airborne Visual\\/Infrared Imaging Spectrometer (AVIRIS) for methane remote sensing of this marine source.

B. P. Luyendyk; I. Leifer; D. Roberts; J. S. Margolis

2006-01-01

377

Oils Spills  

NSDL National Science Digital Library

This page from the US Environmental Protection Agency's Emergency Management division outlines EPA programs to prevent and respond to oil spill events. There is also information available on the environmental dangers posed by oil and how different technologies are used to clean up spills both in oceans and freshwater.

Division, Emergency M.; Agency, Us E.

378

Barley Oil  

Technology Transfer Automated Retrieval System (TEKTRAN)

Barley (Hordeum vulgare) is an ancient grain that has was domesticated for use as a food. Currently only about 2% is used for food, about two thirds is used for animal feed and one third for malting. Because the oil content of most barley cultivars is low (<2%), obtaining oil from whole barley gra...

379

Oil Tankers  

NSDL National Science Digital Library

This website on oil tankers explains how their size is a consequence of how their volume and surface area scale up. A cross-section diagram shows how the relative size of oil tankers has grown from the 1950s to the 1990s. Limiting factors on the size of tankers are also discussed.

2007-07-20

380

Antidiabetic oils.  

PubMed

Many studies have demonstrated evidence of the health benefits of natural products. Plant extracts have been tested on a variety of physiological disorders, including diabetes mellitus. Studies have tested aqueous extracts, plant fractions extracts, families of active of compounds, and specific active compounds. In this review, we describe the antidiabetic effects of vegetable oils. Information was collected from ScienceDirect and PubMed databases using the following key words: Diabetes mellitus, Oils, Vegetable oils, Type 1 diabetes, type 2 diabetes, antidiabetic effect, antihyperglycemic, antidiabetic oil. We have compiled approximately ten vegetable oils with including experimental studies that have demonstrated benefits on diabetes mellitus. There are soybean, argan, olive, palm, walnut, black cumin, safflower, Colocynth, Black seed, Rice bran, Cinnamom, and Rocket oils. For each vegetable oil, we investigated on the plant's traditional uses, their pharmacological activities and their antidiabetic effects. It seems that many vegetable oils are really interesting and can be used in the improvement of human health, particularly, to prevent or to treat diabetes mellitus complications. PMID:24111621

Berraaouan, Ali; Abid, Sanae; Bnouham, Mohamed

2013-11-01

381

Wavelets in oil industry  

NASA Astrophysics Data System (ADS)

In this chapter, the role of wavelet methods applied to identification and characterization of oil reservoir is elaborated. The market rate of petroleum product is very much related to exploration, drilling and production cost. The main goal of researchers working in oil industry is to develop tools and techniques for minimizing cost of exploration and production. Efforts of researchers working in applications of wavelet methods in different parts of the world to achieve this goal is reviewed. Wavelet based solution of Buckley-Leverett equation modelling reservoir is discussed. Variants of Buckley-Leverett equations including its higher dimension versions are introduced. Wavelet methods for inverse problems associated with Buckley-Leverett equation, which are quite useful for oil recovery, are also explained in this chapter.

Siddiqi, A. H.

2012-07-01

382

Finding new reserves of oil and gas As the world's reserves of oil and gas become exhausted, we urgently need to find new  

E-print Network

Finding new reserves of oil and gas As the world's reserves of oil and gas become exhausted, we urgently need to find new fields to answer our energy needs. Oil companies are keen to use novel techniques) techniques represent arguably the most significant technological advance in the field of oil exploration

Anderson, Jim

383

Analysis on the formation condition of the algae-induced odorous black water agglomerate  

PubMed Central

The algae-induced odorous black water agglomerate (OBWA) is a phenomenon in which water turns black and emits odorous gas. It is an ecological and environmental problem that has occurred several times in Taihu, a large eutrophic shallow lake in China. In this study, the collected eutrophic water with different algae densities was used to simulate OBWA. The results revealed that the massive accumulation and death of algae was the substrate source for OBWA. When the algae density reached 1.0 × 108 cells/L in the static and dark condition, at a constant high temperature (30 ± 2 °C), OBWA happened. There was a time difference between the water stinking and blackening with the stinking first. When the oxidation–reduction potential (ORP) value was between ?250 and ?50 mV, Dimethyl trisulfide (DMTS), the main contributor to the water stinking at the initial stage, and other odorous organics were produced. Water blackening was closely related to the increases of sulfide and dissolved Fe2+ concentration. When the ORP value was between ?350 and ?300 mV, heavy metal containing sulfides such as FeS formed. Therefore, the condition when the water ORP value decreased to about ?300 mV was considered the precursor for OBWA formation. PMID:25473369

Wang, Guofang; Li, Xianning; Fang, Yang; Huang, Rui

2014-01-01

384

Analysis on the formation condition of the algae-induced odorous black water agglomerate.  

PubMed

The algae-induced odorous black water agglomerate (OBWA) is a phenomenon in which water turns black and emits odorous gas. It is an ecological and environmental problem that has occurred several times in Taihu, a large eutrophic shallow lake in China. In this study, the collected eutrophic water with different algae densities was used to simulate OBWA. The results revealed that the massive accumulation and death of algae was the substrate source for OBWA. When the algae density reached 1.0 × 10(8) cells/L in the static and dark condition, at a constant high temperature (30 ± 2 °C), OBWA happened. There was a time difference between the water stinking and blackening with the stinking first. When the oxidation-reduction potential (ORP) value was between -250 and -50 mV, Dimethyl trisulfide (DMTS), the main contributor to the water stinking at the initial stage, and other odorous organics were produced. Water blackening was closely related to the increases of sulfide and dissolved Fe(2+) concentration. When the ORP value was between -350 and -300 mV, heavy metal containing sulfides such as FeS formed. Therefore, the condition when the water ORP value decreased to about -300 mV was considered the precursor for OBWA formation. PMID:25473369

Wang, Guofang; Li, Xianning; Fang, Yang; Huang, Rui

2014-12-01

385

Coal-gold agglomeration: an alternative separation process in gold recovery  

SciTech Connect

Considering the increasing environmental concerns and the potential for small gold deposits to be exploited in the future, the uses of environmentally friendly processes are essential. Recent developments point to the potential for greatly increased plant performance through a separation process that combines the cyanide and flotation processes. In addition, this kind of alternative treatment processes to the traditional gold recovery processes may reduce the environmental risks of present small-scale gold mining. Gold recovery processes that applied to different types of gold bearing ore deposits show that the type of deposits plays an important role for the selection of mineral processing technologies in the production of gold and other precious metals. In the last 25 years, different alternative processes have been investigated on gold deposits located in areas where environmental issues are a great concern. In 1988, gold particles were first recovered by successful pilot trial of coal-gold agglomeration (CGA) process in Australia. The current paper reviews the importance of CGA in the production of gold ore and identifies areas for further development work.

Akcil, A.; Wu, X.Q.; Aksay, E.K. [Suleyman Demirel University, Isparta (Turkey). Dept. of Mining Engineering

2009-07-01

386

Impact of anthropogenic heat release on regional climate in three vast urban agglomerations in China  

NASA Astrophysics Data System (ADS)

We simulated the impact of anthropogenic heat release (AHR) on the regional climate in three vast city agglomerations in China using the Weather Research and Forecasting model with nested high-resolution modeling. Based on energy consumption and high-quality land use data, we designed two scenarios to represent no-AHR and current-AHR conditions. By comparing the results of the two numerical experiments, changes of surface air temperature and precipitation due to AHR were quantified and analyzed. We concluded that AHR increases the temperature in these urbanized areas by about 0.5°C—1°C, and this increase is more pronounced in winter than in other seasons. The inclusion of AHR enhances the convergence of water vapor over urbanized areas. Together with the warming of the lower troposphere and the enhancement of ascending motions caused by AHR, the average convective available potential energy in urbanized areas is increased. Rainfall amounts in summer over urbanized areas are likely to increase and regional precipitation patterns to be altered to some extent.

Feng, Jinming; Wang, Jun; Yan, Zhongwei

2014-03-01

387

Synthesis of agglomerate-free YAG: Ce3+ phosphors by co-precipitation and low temperature spray pyrolysis  

Microsoft Academic Search

Y3?xCexAl5O12 (YAG: Ce3+) phosphor particles were prepared by a new method called co-precipitation and low temperature spray pyrolysis (CP-LTSP) with oxalic acid and ammonia as precipitant. It corresponds to the first-step chemical liquid reaction, the second step dehydration and partial decomposition of precipitation droplets at 250°C and then heating at 1100°C or above. Spherical as-prepared particles and agglomerate-free YAG: Ce3+

Shengxia Gao; Yibin Chen; Renjie Zeng

2011-01-01

388

IMPACT OF PARTICLE SIZE AND AGGLOMERATION ON SETTLING OF SOLIDS IN CONTINUOUS MELTERS PROCESSING RADIOACTIVE WASTE GLASS  

SciTech Connect

The major factor limiting waste loading for many waste compositions in continuous waste glass melters is the settling of crystalline materials. The currently used constraints, i.e., the minimum liquidus temperature or the maximum fraction of equilibrium crystallinity at a given temperature, are based on thennodynamic equilibria. Because of the rapid circular convection in the melter, these constraints are probably irrelevant and cannot prevent large crystals from settling. The main factor that detennines the rate of settling ofindividual crystals, such as those ofspinel, is their size. The tiny crystals of RU02 are too small to settle, but they readily fonn large agglomerates that accelerate their rate ofsettling by severalorders ofmagnitude. The RU02 agglomerates originate early in the melting process and then grow by the shear-flocculation mechanism. It is estimated that these agglomerates must either be ofhundreds micrometers in size or have an elongated shape to match the observed rates ofthe sludge-layer fonnation. PACS: 47.57.ef, 81.05.Kj, 81.10.Fg

HRMA PR

2008-12-18

389

Particle aerosolisation and break-up in dry powder inhalers: evaluation and modelling of impaction effects for agglomerated systems.  

PubMed

This study utilised a combination of computational fluid dynamics (CFD) and standardised entrainment tubes to investigate the influence of impaction on the break-up and aerosol performance of a model inhalation formulation. A series of entrainment tubes, with different impaction plate angles were designed in silico and the flow characteristics, and particle tracks, were simulated using CFD. The apparatuses were constructed using three-dimensional printing. The deposition and aerosol performance of a model agglomerate system (496.3-789.2 ?m agglomerates containing 3.91 ?m median diameter mannitol particles) were evaluated by chemical analysis and laser diffraction, respectively. Analysis of the mannitol recovery from the assembly and CFD simulations indicated that mass deposition on the plate was dependent on the impactor angle (45°-90°) but independent of the airflow rate (60-140 L·min(-1)). In comparison, wall losses, perpendicular to the impactor plate were dependent on both the impactor angle and flow rate. Analysis of the particle size distribution exiting the impactor assembly suggested mannitol aerosolisation to be independent of impactor angle but dependent on the air velocity directly above the impactor plate. It is proposed that particle-wall impaction results in initial agglomerate fragmentation followed by reentrainment in the airstream above the impaction plate. Such observations have significant implications in the design of dry powder inhaler devices. PMID:21360707

Wong, William; Fletcher, David F; Traini, Daniela; Chan, Hak-kim; Crapper, John; Young, Paul M

2011-07-01

390

Integrated low emission cleanup system for direct coal-fueled turbines (electrostatic agglomeration). Draft final technical report  

SciTech Connect

The objective of this contract was to investigate the removal of SO{sub x} and particulate matter from direct coal fired combustion gas streams at high temperature and high pressure conditions. This investigation was to be accomplished through a bench scale testing and evaluation program for SO{sub x} removal and the innovative particulate collection concept of particulate growth through electrostatic agglomeration followed by high efficiency mechanical collection. The process goal was to achieve control better than that required by 1979 New Source Performance Standards. During Phase I, the designs of the combustor and gas cleanup apparatus were successfully completed. Hot gas cleanup was designed to be accomplished at temperature levels between 1800{degrees} and 2500{degrees}F at pressures up to 15 atmospheres. The combustor gas flow rate could be varied between 0.2--0.5 pounds per second. The electrostatic agglomerator residence time could be varied between 0.25 to 3 seconds. In Phase II, all components were fabricated, and erected successfully. Test data from shakedown testing was obtained. Unpredictable difficulties in pilot plant erection and shakedown consumed more budget resources than was estimated and as a consequence DOE, METC, decided ft was best to complete the contract at the end of Phase II. Parameters studied in shakedown testing revealed that high-temperature high pressure electrostatics offers an alternative to barrier filtration in hot gas cleanup but more research is needed in successful system integration between the combustor and electrostatic agglomerator.

Quimby, J.M.; Kumar, K.S.

1992-12-31

391

Research on Oil Recovery Mechanisms in Heavy Oil Reservoirs  

SciTech Connect

The goal of this project is to increase recovery of heavy oils. Towards that goal studies are being conducted in how to assess the influence of temperature and pressure on the absolute and relative permeability to oil and water and on capillary pressure; to evaluate the effect of different reservoir parameters on the in site combustion process; to develop and understand mechanisms of surfactants on for the reduction of gravity override and channeling of steam; and to improve techniques of formation evaluation.

Louis M. Castanier; William E. Brigham

1998-03-31

392

Essential oils encapsulated in liposomes: a review.  

PubMed

In the recent years there has been an increased interest toward the biological activities of essential oils. However, essential oils are unstable and susceptible to degradation in the presence of oxygen, light and temperature. So, attempts have been made to preserve them through encapsulation in various colloidal systems such as microcapsules, microspheres, nanoemulsions and liposomes. This review focuses specifically on encapsulation of essential oils into liposomes. First, we present the techniques used to prepare liposomes encapsulating essential oils. The effects of essential oils and other factors on liposome characteristics such as size, encapsulation efficiency and thermal behavior of lipid bilayers are then discussed. The composition of lipid vesicles membrane, especially the type of phospholipids, cholesterol content, the molar ratio of essential oils to lipids, the preparation method and the kind of essential oil may affect the liposome size and the encapsulation efficiency. Several essential oils can decrease the size of liposomes, homogenize the liposomal dispersions, increase the fluidity and reduce the oxidation of the lipid bilayer. Moreover, liposomes can protect the fluidity of essential oils and are stable at 4-5?°C for 6 months at least. The applications of liposomes incorporating essential oils are also summarized in this review. Liposomes encapsulating essential oils are promising agents that can be used to increase the anti-microbial activity of the essential oils, to study the effect of essential oils on cell membranes, and to provide alternative therapeutic agents to treat several diseases. PMID:23879218

Sherry, Mirna; Charcosset, Catherine; Fessi, Hatem; Greige-Gerges, Hélène

2013-12-01

393

Internal self-ordering in In(Sb,As), (In,Ga)Sb, and (Cd,Zn,Mn)Se nano-agglomerates\\/quantum dots  

Microsoft Academic Search

Nano-agglomerates of In(Sb,As) in InAs, (In,Ga)Sb in GaSb, and (Cd,Zn,Mn)Se in (Zn,Mn)Se are classified by transmission electron microscopy. In scanning transmission electron microscopy, atomic resolution Z-contrast images reveal different modes of internal compositional modulation on the atomic length scale, resulting for all three material systems in nano-agglomerates of an appropriate size that may constitute a new type of quantum dot.

P. Moeck; T. Topuria; N. D. Browning; G. R. Booker; N. J. Mason; R. J. Nicholas; M. Dobrowolska; S. Lee; J. K. Furdyna

2001-01-01

394

Oil Types  

MedlinePLUS

... 6 Fuel Oil, Bunker C) Little or no evaporation or dissolution. Heavy contamination of intertidal areas likely. ... another liquid in the form of small droplets. Evaporation: The process whereby any substance is converted from ...

395

Essential oils: SPE fractionation  

Microsoft Academic Search

Summary  Essential oil analysis is often characterised by mixtures that are difficult to separate. The components belong to different\\u000a classes of compounds that range widely in concentration. Hence, a pre-separation technique is often required, at least to\\u000a evaluate the minor components. This paper reports an SPE method to overcome this problem. The method was developed with a\\u000a standard solution that yielded

A. Antonelli; C. Fabbri

1999-01-01

396

Increased oil production and reserves from improved completion techniques in the Bluebell Field, Uinta Basin, Utah. Annual report, September 30, 1993--September 30, 1994  

SciTech Connect

The Bluebell field produces from the Tertiary lower Green River and Wasatch Formations of the Uinta Basin, Utah. The productive interval consists of thousands of feet of interbedded fractured clastic and carbonate beds deposited in a fluvial-dominated deltaic lacustrine environment, sandstones deposited in fluvial-dominated deltas; and carbonates and some interbedded sandstones of the lower Wasatch transition deposited in mud flats. Bluebell project personnel are studying ways to improve completion techniques used in the field to increase primary production in both new wells and recompletions. The study includes detailed petrographic examination of the different lithologic reservoir types in both the outcrop and core. Outcrop, core, and geophysical logs are being used to identify and map important depositional cycles. Petrographic detail will be used to improve log calculation methods which are currently highly questionable due to varying water chemistry and clay content in the Green River and Wasatch Formations. Field mapping of fractures and their relationship to basin tectonics helps predict the orientation of open fractures in the subsurface. The project includes acquiring bore-hole imaging logs from new wells in the Bluebell field thereby obtaining detailed subsurface fracture data previously not available. Reservoir simulation models are being constructed to improve the understanding of pressure and fluid flow within the reservoir. A detailed database of well completion histories has been compiled and will be studied to determine which were the most and the least effective methods used in the past.

Allison, M.

1995-07-01

397

Oil reserve  

SciTech Connect

This paper reports on the crisis in the Persian Gulf which has renewed interest in the ability of the Department of Energy's Strategic Petroleum Reserve to counter disruptions in the supply of oil to the United States. To provide this protection, DOE must be able to offset the supplies lost by quickly drawing down reserve oil from its storage sites and distributing it to purchasers. This report reviews DOE's current and planned capability for removing oil from reserve sites and getting it to users via oil distribution networks, examines the Strategic Petroleum Reserve's compliance with pipeline safety requirements, and discusses DOE's efforts to correct problems that GAO previously reported. GAO concludes that a major distribution could be hampered because buyers of Strategic Petroleum Reserve oil are required to use U.S.-flag tankers to ship the oil between U.S. ports. DOE and industry officials doubt whether enough U.S.-flag vessels are available to do the job, and questions remain about the efficiency of procedures to authorize the use of foreign vessels.

Not Available

1991-01-01

398

Fundamental studies on mineral matter behavior in ash-agglomerating coal gasifiers  

SciTech Connect

The Institute of Gas Technology is conducting a research program on ash chemistry to predict the behavior of the mineral matter in a fluidized-bed gasifier and its downstream units based on a minimum analysis of the characteristics of the mineral matter present in the coal feed and on the operating conditions. The bench-scale fundamental research investigation on the behavior of mineral matter, contained in chars from Pittsburgh Seam Coal from the Consolidation Coal Company's Ireland Mine in Marshall County, West Virginia, and from the No. 11 seam of Kentucky coal, were conducted in a 2-inch ID gasifier with a perforated plate gas distributor at atmospheric pressure, at 1255 and 1366 K, with char carbon conversions ranging from 24% to 94%. Some of the tests were conducted with low oxygen, 0.31 to 0.32 mole percent in the feed gas and others with 5.0 to 5.7 mole percent oxygen to investigate the effect of temperature due to the reaction of oxygen with the char. Feed chars ad char residues obtained from the 2-inch-ID batch gasification tests were analyzed chemically and by Moessbauer spectroscopy and were examined by optical petrography. The data analysis indicate that, during gasification the pyrite decomposes to ferrous sulfide and, at times, a minor amount of metallic iron. The ferrous sulfide in the interior of the char particles remains stable until exposed by burn-off of the char. As gasification proceeds, some of the iron compounds react with clays and silica to form low-melting ferrous alumino-silicates. In the tests without the center jet, roughly 30% of the iron became silicate, mostly in poorly defined forms. In pilot plant runs, the ferrous aluminosilicate serves as the agglutinating agent, embedding other ash particles and forming nearly spherical and dense agglomerates that selectively drop out of the fluidized gasification zone. 3 refs, 6 figs., 4 tabs.

Carty, R.H.; Mason, D.M.; Babu, S.P.

1986-09-01

399

Urban influence on increasing ozone concentrations in a characteristic Mediterranean agglomeration  

NASA Astrophysics Data System (ADS)

Air quality in cities has been extensively studied due to the high population density potentially exposed to high levels of pollutants. The main problems in urban areas have been related to particulate matter (PM) and NO2. Less attention has been directed towards O3 because urban levels are generally lower than those recorded in rural areas. The implementation of air quality plans, together with technological improvements, have resulted in reductions of PM and NO2 levels in many European cities. In contrast, urban O3 levels have experimented increases which may respond to declining NOx emission trends. It is therefore necessary to intensify the study of urban O3 and its potential relation with NOx variations. In the agglomeration of Zaragoza (NE Spain), traffic circulation through the centre has dropped by 28.3% since 2008 due to several factors such as the implementation of a mobility plan, the completion of major construction projects and the economic crisis in Spain. The study of this case offers a unique opportunity to evaluate the impact of reductions in NOx emissions on the levels of O3 in a characteristic Mediterranean city. This work analyses the variability and trends of ambient air levels of O3 and NOx in Zaragoza and the Ebro valley from 2007 to 2012. Results demonstrate that, although the main factor explaining O3 variability is still linked to meteorology, changes in NOx emissions strongly influence O3 variability and trends, mainly due to interaction with fresh NO. Specific analysis of the O3 "weekend effect" show a significant correlation (r2 = 0.81) between the drop of NO concentrations (associated to emissions) and the increment of O3 levels during weekends. Moreover, trend analyses reveal that the decline in NOx emissions in Zaragoza from 2007 to 2012 can be associated with significant increments in O3 levels.

Escudero, M.; Lozano, A.; Hierro, J.; Valle, J. del; Mantilla, E.

2014-12-01

400

Use of Cutting-Edge Horizontal and Underbalanced Drilling Technologies and Subsurface Seismic Techniques to Explore, Drill and Produce Reservoired Oil and Gas from the Fractured Monterey Below 10,000 ft in the Santa Maria Basin of California  

SciTech Connect

This project was undertaken to demonstrate that oil and gas can be drilled and produced safely and economically from a fractured Monterey reservoir in the Santa Maria Basin of California by employing horizontal wellbores and underbalanced drilling technologies. Two vertical wells were previously drilled in this area with heavy mud and conventional completions; neither was commercially productive. A new well was drilled by the project team in 2004 with the objective of accessing an extended length of oil-bearing, high-resistivity Monterey shale via a horizontal wellbore, while implementing managed-pressure drilling (MPD) techniques to avoid formation damage. Initial project meetings were conducted in October 2003. The team confirmed that the demonstration well would be completed open-hole to minimize productivity impairment. Following an overview of the geologic setting and local field experience, critical aspects of the application were identified. At the pre-spud meeting in January 2004, the final well design was confirmed and the well programming/service company requirements assigned. Various design elements were reduced in scope due to significant budgetary constraints. Major alterations to the original plan included: (1) a VSP seismic survey was delayed to a later phase; (2) a new (larger) surface hole would be drilled rather than re-enter an existing well; (3) a 7-in. liner would be placed into the top of the Monterey target as quickly as possible to avoid problems with hole stability; (4) evaluation activities were reduced in scope; (5) geosteering observations for fracture access would be deduced from penetration rate, cuttings description and hydrocarbon in-flow; and (6) rather than use nitrogen, a novel air-injection MPD system was to be implemented. Drilling operations, delayed from the original schedule by capital constraints and lack of rig availability, were conducted from September 12 to November 11, 2004. The vertical and upper curved sections were drilled and lined through the problematic shale member without major stability problems. The top of the targeted Monterey was thought to be seen at the expected TVD of 10,000 ft where the 7-in. liner was set at a 60{sup o} hole angle. Significant oil and gas shows suggested the fractured interval anticipated at the heel location had been penetrated. A total of 2572 ft of 6{Delta}-in. near-horizontal interval was placed in the shale section, extending planned well length by approximately 470 ft. Very little hydrocarbon in-flow was observed from fractures along the productive interval. This may be a result of the well trajectory falling underneath the Monterey fractured zone. Hydrocarbon observations, cuttings analysis and gamma-ray response indicated additional fractured intervals were accessed along the last {+-}900 ft of well length. The well was completed with a 2 and 7/8-in. tubing string set in a production packer in preparation for flow and swab tests to be conducted later by a service rig. The planned well time was estimated as 39 days and overall cost as $2.4 million. The actual results are 66 days at a total cost of $3.4 million. Well productivity responses during subsequent flow and swabbing tests were negative. The well failed to inflow and only minor amounts (a few barrels) of light oil were recovered. The lack of production may suggest that actual sustainable reservoir pressure is far less than anticipated. Temblor attempted in July, 2006, to re-enter and clean out the well and run an Array Induction log (primarily for resistivity and correlation purposes), and an FMI log (for fracture detection). Application of surfactant in the length of the horizontal hole, and acid over the fracture zone at 10,236 was also planned. This attempt was not successful in that the clean out tools became stuck and had to be abandoned.

George Witter; Robert Knoll; William Rehm; Thomas Williams

2006-06-30

401

Use of Cutting-Edge Horizontal and Underbalanced Drilling Technologies and Subsurface Seismic Techniques to Explore, Drill and Produce Reservoired Oil and Gas from the Fractured Monterey Below 10,000 ft in the Santa Maria Basin of California  

SciTech Connect

This project was undertaken to demonstrate that oil and gas can be drilled and produced safely and economically from a fractured Monterey reservoir in the Santa Maria Basin of California by employing horizontal wellbores and underbalanced drilling technologies. Two vertical wells were previously drilled in this area with heavy mud and conventional completions; neither was commercially productive. A new well was drilled by the project team in 2004 with the objective of accessing an extended length of oil-bearing, high-resistivity Monterey shale via a horizontal wellbore, while implementing managed-pressure drilling (MPD) techniques to avoid formation damage. Initial project meetings were conducted in October 2003. The team confirmed that the demonstration well would be completed open-hole to minimize productivity impairment. Following an overview of the geologic setting and local field experience, critical aspects of the application were identified. At the pre-spud meeting in January 2004, the final well design was confirmed and the well programming/service company requirements assigned. Various design elements were reduced in scope due to significant budgetary constraints. Major alterations to the original plan included: (1) a VSP seismic survey was delayed to a later phase; (2) a new (larger) surface hole would be drilled rather than re-enter an existing well; (3) a 7-in. liner would be placed into the top of the Monterey target as quickly as possible to avoid problems with hole stability; (4) evaluation activities were reduced in scope; (5) geosteering observations for fracture access would be deduced from penetration rate, cuttings description and hydrocarbon in-flow; and (6) rather than use nitrogen, a novel air-injection MPD system was to be implemented. Drilling operations, delayed from the original schedule by capital constraints and lack of rig availability, were conducted from September 12 to November 11, 2004. The vertical and upper curved sections were drilled and lined through the problematic shale member without major stability problems. The top of the targeted Monterey was thought to be seen at the expected TVD of 10,000 ft where the 7-in. liner was set at a 60{sup o} hole angle. Significant oil and gas shows suggested the fractured interval anticipated at the heel location had been penetrated. A total of 2572 ft of 6 1/8-in. near-horizontal interval was placed in the shale section, extending planned well length by approximately 470 ft. Very little hydrocarbon in-flow was observed from fractures along the productive interval. This may be a result of the well trajectory falling underneath the Monterey fractured zone. Hydrocarbon observations, cuttings analysis and gamma-ray response indicated additional fractured intervals were accessed along the last {+-}900 ft of well length. The well was completed with a 2 7/8-in. tubing string set in a production packer in preparation for flow and swab tests to be conducted later by a service rig. The planned well time was estimated as 39 days and overall cost as $2.4 million. The actual results are 66 days at a total cost of $3.4 million. Well productivity responses during subsequent flow and swabbing tests were negative. The well failed to inflow and only minor amounts (a few barrels) of light oil were recovered. The lack of production may suggest that actual sustainable reservoir pressure is far less than anticipated. Temblor is currently planning to re-enter and clean out the well and run an Array Induction log (primarily for resistivity and correlation purposes), and an FMI log (for fracture detection). Depending on the results of these logs, an acidizing or re-drill program will be planned.

George Witter; Robert Knoll; William Rehm; Thomas Williams

2005-09-29

402

USE OF CUTTING-EDGE HORIZONTAL AND UNDERBALANCED DRILLING TECHNOLOGIES AND SUBSURFACE SEISMIC TECHNIQUES TO EXPLORE, DRILL AND PRODUCE RESERVOIRED OIL AND GAS FROM THE FRACTURED MONTEREY BELOW 10,000 FT IN THE SANTA MARIA BASIN OF CALIFORNIA  

SciTech Connect

This project was undertaken to demonstrate that oil and gas can be drilled and produced safely and economically from a fractured Monterey reservoir in the Santa Maria Basin of California by employing horizontal wellbores and underbalanced drilling technologies. Two vertical wells were previously drilled in this area by Temblor Petroleum with heavy mud and conventional completions; neither was commercially productive. A new well was drilled by the project team in 2004 with the objective of accessing an extended length of oil-bearing, high-resistivity Monterey shale via a horizontal wellbore, while implementing managed-pressure drilling (MPD) techniques to avoid formation damage. Initial project meetings were conducted in October 2003. The team confirmed that the demonstration well would be completed open-hole to minimize productivity impairment. Following an overview of the geologic setting and local field experience, critical aspects of the application were identified. At the pre-spud meeting in January 2004, the final well design was confirmed and the well programming/service company requirements assigned. Various design elements were reduced in scope due to significant budgetary constraints. Major alterations to the original plan included: (1) a VSP seismic survey was delayed to a later phase; (2) a new (larger) surface hole would be drilled rather than re-enter an existing well; (3) a 7-in. liner would be placed into the top of the Monterey target as quickly as possible to avoid problems with hole stability; (4) evaluation activities were reduced in scope; (5) geosteering observations for fracture access would be deduced from penetration rate, cuttings description and hydrocarbon in-flow; and (6) rather than use nitrogen, a novel air-injection MPD system was to be implemented. Drilling operations, delayed from the original schedule by capital constraints and lack of rig availability, were conducted from September 12 to November 11, 2004. The vertical and upper curved sections were drilled and lined through the problematic shale member without major stability problems. The top of the targeted Monterey was thought to be seen at the expected TVD of 10,000 ft where the 7-in. liner was set at a 60{sup o} hole angle. Significant oil and gas shows suggested the fractured interval anticipated at the heel location had been penetrated. A total of 2572 ft of 6.-in. near-horizontal interval was placed in the shale section, extending planned well length by approximately 470 ft. Very little hydrocarbon in-flow was observed from fractures along the productive interval. This may be a result of the well trajectory falling underneath the Monterey fractured zone. Hydrocarbon observations, cuttings analysis and gamma-ray response indicated additional fractured intervals were accessed along the last {+-}900 ft of well length. The well was completed with a 2 7/8-in. tubing string set in a production packer in preparation for flow and swab tests to be conducted later by a service rig. The planned well time was estimated as 39 days and overall cost as $2.4 million. The actual results are 66 days at a total cost of $3.4 million. Well productivity responses during subsequent flow and swabbing tests were negative. The well failed to inflow and only minor amounts (a few barrels) of light oil were recovered. The lack of production may suggest that actual sustainable reservoir pressure is far less than anticipated. Temblor is currently investigating the costs and operational viability of re-entering the well and conducting an FMI (fracture detection) log and/or an acid stimulation. No final decision or detailed plans have been made regarding these potential interventions at this time.

George Witter; Robert Knoll; William Rehm; Thomas Williams

2005-02-01

403

Evaluation of the antifungal effects of bio-oil prepared with lignocellulosic biomass using fast pyrolysis technology.  

PubMed

This study was performed to investigate the utility of bio-oil, produced via a fast pyrolysis process, as an antifungal agent against wood-rot fungi. Bio-oil solutions (25-100 wt.%) were prepared by diluting the bio-oil with EtOH. Wood block samples (yellow poplar and pitch pine) were treated with diluted bio-oil solutions and then subjected to a leaching process under hot water (70°C) for 72 h. After the wood block samples were thoroughly dried, they were subjected to a soil block test using Tyromyces palustris and Trametes versicolor. The antifungal effect of the 75% and 100% bio-oil solutions was the highest for both wood blocks. Scanning electron microscopy analysis indicated that some chemical components in the bio-oil solution could agglomerate together to form clusters in the inner part of the wood during the drying process, which could act as a wood preservative against fungal growth. According to GC/MS analysis, the components of the agglomerate were mainly phenolic compounds derived from lignin polymers. PMID:22784866

Kim, Kwang Ho; Jeong, Han Seob; Kim, Jae-Young; Han, Gyu Seong; Choi, In-Gyu; Choi, Joon Weon

2012-10-01

404

Review of oil spill remote sensing.  

PubMed

Remote-sensing for oil spills is reviewed. The use of visible techniques is ubiquitous, however it gives only the same results as visual monitoring. Oil has no particular spectral features that would allow for identification among the many possible background interferences. Cameras are only useful to provide documentation. In daytime oil absorbs light and remits this as thermal energy at temperatures 3-8K above ambient, this is detectable by infrared (IR) cameras. Laser fluorosensors are useful instruments because of their unique capability to identify oil on backgrounds that include water, soil, weeds, ice and snow. They are the only sensor that can positively discriminate oil on most backgrounds. Radar detects oil on water by the fact that oil will dampen water-surface capillary waves under low to moderate wave/wind conditions. Radar offers the only potential for large area searches, day/night and foul weather remote sensing. PMID:24759508

Fingas, Merv; Brown, Carl

2014-06-15

405

Extreme Oil  

NSDL National Science Digital Library

The quest for oil continues unabated across the globe, and this latest documentary series produced by Thirteen/WNET New York examines the various ways in which various interests work to find new sources of this very important natural resource. The site is divided into three compelling sections, and visitors would do well to start with the area titled "The Journey". Here they will learn about the distance that oil must travel, as it moves from its place of origin all the way to its use as a fuel source, or any of its thousands of other uses. The four oil transport networks profiled here include the famed BTC Pipeline and the Trans-Alaskan Pipeline. The history section of the site offers a helpful (and visually rich) timeline of the evolution of the use of oil by humans that dates back all the way to the year 480 BC. Finally, the last section deals with the science of oil extraction and related technologies, and includes information on refining and production of this resource.

406

Coreflood assay using extremophile microorganisms for recovery of heavy oil in Mexican oil fields.  

PubMed

A considerable portion of oil reserves in Mexico corresponds to heavy oils. This feature makes it more difficult to recover the remaining oil in the reservoir after extraction with conventional techniques. Microbial enhanced oil recovery (MEOR) has been considered as a promising technique to further increase oil recovery, but its application has been developed mainly with light oils; therefore, more research is required for heavy oil. In this study, the recovery of Mexican heavy oil (11.1°API and viscosity 32,906 mPa s) in a coreflood experiment was evaluated using the extremophile mixed culture A7, which was isolated from a Mexican oil field. Culture A7 includes fermentative, thermophilic, and anaerobic microorganisms. The experiments included waterflooding and MEOR stages, and were carried out under reservoir conditions (70°C and 9.65 MPa). MEOR consisted of injections of nutrients and microorganisms followed by confinement periods. In the MEOR stages, the mixed culture A7 produced surface-active agents (surface tension reduction 27 mN m?¹), solvents (ethanol, 1738 mg L?¹), acids (693 mg L?¹), and gases, and also degraded heavy hydrocarbon fractions in an extreme environment. The interactions of these metabolites with the oil, as well as the bioconversion of heavy oil fractions to lighter fractions (increased alkanes in the C?-C?? range), were the mechanisms responsible for the mobility and recovery of heavy oil from the porous media. Oil recovery by MEOR was 19.48% of the residual oil in the core after waterflooding. These results show that MEOR is a potential alternative to heavy oil recovery in Mexican oil fields. PMID:22704814

Castorena-Cortés, Gladys; Roldán-Carrillo, Teresa; Reyes-Avila, Jesús; Zapata-Peñasco, Icoquih; Mayol-Castillo, Martha; Olguín-Lora, Patricia

2012-10-01

407

Factoring-in agglomeration of carbon nanotubes and nanofibers for better prediction of their toxicity versus asbestos  

PubMed Central

Background Carbon nanotubes (CNT) and carbon nanofibers (CNF) are allotropes of carbon featuring fibrous morphology. The dimensions and high aspect ratio of CNT and CNF have prompted the comparison with naturally occurring asbestos fibers which are known to be extremely pathogenic. While the toxicity and hazardous outcomes elicited by airborne exposure to single-walled CNT or asbestos have been widely reported, very limited data are currently available describing adverse effects of respirable CNF. Results Here, we assessed pulmonary inflammation, fibrosis, oxidative stress markers and systemic immune responses to respirable CNF in comparison to single-walled CNT (SWCNT) and asbestos. Pulmonary inflammatory and fibrogenic responses to CNF, SWCNT and asbestos varied depending upon the agglomeration state of the particles/fibers. Foci of granulomatous lesions and collagen deposition were associated with dense particle-like SWCNT agglomerates, while no granuloma formation was found following exposure to fiber-like CNF or asbestos. The average thickness of the alveolar connective tissue - a marker of interstitial fibrosis - was increased 28 days post SWCNT, CNF or asbestos exposure. Exposure to SWCNT, CNF or asbestos resulted in oxidative stress evidenced by accumulations of 4-HNE and carbonylated proteins in the lung tissues. Additionally, local inflammatory and fibrogenic responses were accompanied by modified systemic immunity, as documented by decreased proliferation of splenic T cells ex vivo on day 28 post exposure. The accuracies of assessments of effective surface area for asbestos, SWCNT and CNF (based on geometrical analysis of their agglomeration) versus estimates of mass dose and number of particles were compared as predictors of toxicological outcomes. Conclusions We provide evidence that effective surface area along with mass dose rather than specific surface area or particle number are significantly correlated with toxicological responses to carbonaceous fibrous nanoparticles. Therefore, they could be useful dose metrics for risk assessment and management. PMID:22490147

2012-01-01

408

Overlapping Schwarz for Nonlinear Problems. An Element Agglomeration Nonlinear Additive Schwarz Preconditioned Newton Method for Unstructured Finite Element Problems  

SciTech Connect

This paper extends previous results on nonlinear Schwarz preconditioning ([4]) to unstructured finite element elliptic problems exploiting now nonlocal (but small) subspaces. The non-local finite element subspaces are associated with subdomains obtained from a non-overlapping element partitioning of the original set of elements and are coarse outside the prescribed element subdomain. The coarsening is based on a modification of the agglomeration based AMGe method proposed in [8]. Then, the algebraic construction from [9] of the corresponding non-linear finite element subproblems is applied to generate the subspace based nonlinear preconditioner. The overall nonlinearly preconditioned problem is solved by an inexact Newton method. Numerical illustration is also provided.

Cai, X C; Marcinkowski, L; Vassilevski, P S

2005-02-10

409

Effect of wettability on the agglomeration of silicon nanowire arrays fabricated by metal-assisted chemical etching.  

PubMed

The effect of wettability on the undesirable bundling of silicon nanowire (SiNW) arrays fabricated by metal-assisted chemical etching (MACE) method is investigated. This paper reports a simple and low-cost approach to achieve dense SiNW arrays with excellent lateral separation. A hydrophilic pretreatment on the initial wafer substrate prior to the etching procedure, followed by a hydrophobic post-treatment of the fabricated SiNWs, allows the fabrication of large and dense arrays of SiNWs with no agglomeration. These results are discussed within the framework of the detailed balance of forces acting on the nanowires. PMID:25100577

Togonal, A S; He, Lining; Roca i Cabarrocas, Pere; Rusli

2014-09-01

410

Nano-dot markers for electron tomography formed by electron beam-induced deposition: nanoparticle agglomerates application.  

PubMed

A method allowing fabrication of nano-dot markers for electron tomography was developed using an electron beam-induced deposition in an ordinary dual beam instrument (FIB and SEM) or an SEM. The electron beam deposited nano-dot markers are suitable for automatic alignment of tomographic series. The accuracy of the alignment was evaluated and the method was demonstrated on agglomerated nanoparticle samples using a rod-shaped sample with no missing wedge effect. Simulations were used to assess the effect of marker size on alignment accuracy. PMID:24837022

Hayashida, Misa; Malac, Marek; Bergen, Michael; Li, Peng

2014-09-01

411

Optical detection of oil on water  

NASA Technical Reports Server (NTRS)

Three radiometric techniques utilizing sunlight reflected and backscattered from water bodies have potential application for remote sensing of oil spills. Oil on water can be detected by viewing perpendicular polarization component of reflected light or difference between polarization components. Best detection is performed in ultraviolet or far-red portions of spectrum and in azimuth directions toward or opposite sun.

Millard, J. P.; Arvesen, J. C.

1973-01-01

412

Prudhoe Bay Oil Production Optimization: Using Virtual  

E-print Network

1 Prudhoe Bay Oil Production Optimization: Using Virtual Intelligence Techniques, Stage One: Neural total field oil production by optimizing the gas discharge rates and pressures at the separation to a central compression plant. #12;5 SPE 77659, Mohaghegh, Hutchins, Sisk BACKGROUND 34" and 60" high pressure

Mohaghegh, Shahab

413

THE FEASIBILITY OF IDENTIFYING MYSTERY OIL SPILLS  

EPA Science Inventory

Several off-the-shelf passive tagging techniques for identifying the origin of mystery oil spills were evaluated to determine the viability of enforcement provisions of Maine's Oil Conveyance Law. Duplicating the operating conditions experienced during every-day marine terminals ...

414

Extraction and Analysis of Tomato Seed Oil  

Technology Transfer Automated Retrieval System (TEKTRAN)

Tomato seeds represent a very large waste by-product from the processing of tomatoes into products such as tomato juice, sauce and paste. One potential use for these seeds is as a source of vegetable oil. This research investigated the oil content of tomato seeds using several extraction technique...

415

Science: Oil Slick.  

ERIC Educational Resources Information Center

Presents a science experiment about oil spills and oil pollution for 7th- and 8th-grade science students. This variation on a method used by pollution control experts to clean up oil spills shows students how oil is collected after an oil spill, explaining that with this method, much of the damage from an oil spill can be averted. (SM)

VanCleave, Janice

2000-01-01

416

Oil Spill Activities  

NSDL National Science Digital Library

The Gulf of Maine Aquarium has prepared three classroom activities and lessons on oil spills: Save the Bay, Oil Consumption, and How Big Is an Oil Tanker. Discover the effects of storms and wind on an oil spill, find out how much oil your family uses, and get a sense of just how big an oil tanker is. Site links to other Aquarium modules.

417

Vegetable oils  

Technology Transfer Automated Retrieval System (TEKTRAN)

Biodiesel is a technically competitive alternative to petroleum-derived diesel fuel. It can be obtained from commodity oils and fats such as soybean, sunflower, canola or tallow. However, the available amounts of these biodiesel feedstocks do not suffice to satisfy the long-term need for biodiesel...

418

What Happens Whan an Oil Spill Occurs?  

NSDL National Science Digital Library

Large oil spills are not a common occurrence. When a tanker runs aground or collides with another vessel and releases its cargo to the sea, it's often major news, especially if the spill is near land. The images in this interactive feature show the major oil spill triggered by the 1989 grounding of the tanker Exxon Valdez in Prince William Sound, Alaska, and the techniques and equipment used to limit damage to the environment. A set of interactive animations shows viewers how the effects of an oil spill are influenced by variables such as the nature of the coastline, weather, and the type of oil spilled.

419

What Happens When an Oil Spill Occurs?  

NSDL National Science Digital Library

Large oil spills are not a common occurrence. When a tanker runs aground or collides with another vessel and releases its cargo to the sea, it's often major news, especially if the spill is near land. The images in this interactive feature show the major oil spill triggered by the 1989 grounding of the tanker Exxon Valdez in Prince William Sound, Alaska, and the techniques and equipment used to limit damage to the environment. A set of interactive animations shows viewers how the effects of an oil spill are influenced by variables such as the nature of the coastline, weather, and the type of oil spilled.

420

Quantitative characterization of agglomerates and aggregates of pyrogenic and precipitated amorphous silica nanomaterials by transmission electron microscopy  

PubMed Central

Background The interaction of a nanomaterial (NM) with a biological system depends not only on the size of its primary particles but also on the size, shape and surface topology of its aggregates and agglomerates. A method based on transmission electron microscopy (TEM), to visualize the NM and on image analysis, to measure detected features quantitatively, was assessed for its capacity to characterize the aggregates and agglomerates of precipitated and pyrogenic synthetic amorphous silicon dioxide (SAS), or silica, NM. Results Bright field (BF) TEM combined with systematic random imaging and semi-automatic image analysis allows measuring the properties of SAS NM quantitatively. Automation allows measuring multiple and arithmetically complex parameters simultaneously on high numbers of detected particles. This reduces operator-induced bias and assures a statistically relevant number of measurements, avoiding the tedious repetitive task of manual measurements. Access to multiple parameters further allows selecting the optimal parameter in function of a specific purpose. Using principle component analysis (PCA), twenty-three measured parameters were classified into three classes containing measures for size, shape and surface topology of the NM. Conclusion The presented method allows a detailed quantitative characterization of NM, like dispersions of precipitated and pyrogenic SAS based on the number-based distributions of their mean diameter, sphericity and shape factor. PMID:22709926

2012-01-01

421

Relationship between land use/cover and surface temperatures in the urban agglomeration of Cuiabá-Várzea Grande, Central Brazil  

NASA Astrophysics Data System (ADS)

We focus on the surface urban heat island (SUHI) and the spatiotemporal relationship between land use and surface temperatures (Ts) in Cuiabá-Várzea Grande, Mato Grosso, one of the major urban agglomerations of central-western Brazil, which has suffered intense urbanization processes since the 1960s. Supervised maximum likelihood classifications of optical bands of Landsat Thematic Mapper (Landsat TM) imagery from 1986 and 2007 are applied to generate land use/cover maps. Surface emissivity is determined using the logarithmic transformation of the normalized difference vegetation index. The Ts is retrieved from the thermal bands utilizing a radiative transfer equation. In both cities, urban expansion followed two main development axes, which are reflected in the spatial patterns of Ts. The highest values of Ts were found in bare soil and urbanized areas. Between 1986 and 2007, Ts increased 0.96°C on average and a maximum of 5.49°C in the urban agglomeration. The SUHI in Várzea Grande suffered intensification with an increase of 1.34°C in the downtown area. This tendency was stronger in the center of Cuiabá, where Ts increased 3.12°C. Slowing this rapid rate of temperature increase would demand decisive intervention by municipal authorities, such as restricting annual occupation taxes, reducing the occupation coefficient in new districts, preserving native vegetation, and designating new green areas.

Callejas, Ivan Júlio Apolônio; de Oliveira, Angela Santana; de Moura Santos, Flávia Maria; Durante, Luciane Cleonice; de Jesus Albuquerque Nogueira, Marta Cristina; Zeilhofer, Peter

2011-01-01

422

Influence of dispersive agent on nanomaterial agglomeration and implications for biological effects in vivo or in vitro.  

PubMed

Comparing the dispersing properties of the porcine lung surfactant Curosurf(®) to bovine serum albumin (BSA), the present study investigated how a more close simulation of the in vivo situation influences nanomaterial dispersion and hence the proportion of the administered dose that will reach the in vitro test system, i.e. the ‘effective dose’. Dispersions of 16 OECD reference nanomaterials (ZnO, Ag, TiO(2), CeO(2), SiO(2), and multi-walled carbon nanotubes (MWCNTs) were assessed. Overall, the NMs were better dispersed in the BSA-supplemented medium. BSA-addition combined with ultrasonication proved most effective in deagglomerating MWCNTs, but also reduced agglomeration for most metal oxidenanomaterials as compared to the Curosurf(®) dispersions. However, all materials were at least partially agglomerated in either dispersing agent. For the different nanomaterials, the calculated effective dosage upon 12- or 24-h test substance incubation differed considerably (and to different extents) depending on the applied dispersing agent. When testing nanomaterial effects in vitro, selection of the type of cell culture medium and its additives should take into account what the system is intended to mimic. Study protocols should address whether they aim at best-possible dispersion of the nanomaterials or at simulating more realistically in vivo tissue uptake and distribution. PMID:25458487

Sauer, Ursula G; Aumann, Alexandra; Ma-Hock, Lan; Landsiedel, Robert; Wohlleben, Wendel

2015-02-01

423

Engineering Development of Advanced Physical Fine Coal Cleaning for Premium Fuel Applications: Task 9 - Selective agglomeration Module Testing and Evaluation.  

SciTech Connect

The primary goal of this project was the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope included laboratory research and bench-scale testing of both processes on six coals to optimize the processes, followed by the design, construction, and operation of a 2 t/hr process development unit (PDU). The project began in October, 1992, and is scheduled for completion by September 1997. This report summarizes the findings of all the selective agglomeration (SA) test work performed with emphasis on the results of the PDU SA Module testing. Two light hydrocarbons, heptane and pentane, were tested as agglomerants in the laboratory research program which investigated two reactor design concepts: a conventional two-stage agglomeration circuit and a unitized reactor that combined the high- and low-shear operations in one vessel. The results were used to design and build a 25 lb/hr bench-scale unit with two-stage agglomeration. The unit also included a steam stripping and condensation circuit for recovery and recycle of heptane. It was tested on six coals to determine the optimum grind and other process conditions that resulted in the recovery of about 99% of the energy while producing low ash (1-2 lb/MBtu) products. The fineness of the grind was the most important variable with the D80 (80% passing size) varying in the 12 to 68 micron range. All the clean coals could be formulated into coal-water-slurry-fuels with acceptable properties. The bench-scale results were used for the conceptual and detailed design of the PDU SA Module which was integrated with the existing grinding and dewatering circuits. The PDU was operated for about 9 months. During the first three months, the shakedown testing was performed to fine tune the operation and control of various equipment. This was followed by parametric testing, optimization/confirmatory testing, and finally a 72-hour round the clock production run for each of the three project coals (Hiawatha, Taggart, and Indiana VII). The parametric testing results confirmed that the Taggart coal ground to a D80 of 30 microns could be cleaned to 1 lb ash/MBtu, whereas the Hiawatha and Indiana Vil coals had to be ground to D80s of 40 and 20 microns, respectively, to be cleaned to 2 lb ash/MBtu. The percent solids, residence time, shear intensity (impeller tip speed and energy input per unit volume), and heptane dosage were the main variables that affected successful operation (phase inversion or microagglomerate formation in the high-shear reactor and their growth to 2-3 mm in size during low shear). Downward inclination of the vibrating screen and adequate spray water helped produce the low ash products. Btu recoveries were consistently greater than 98%. Two-stage steam stripping achieved about 99% heptane recovery for recycle to the process. Residual hydrocarbon concentrations were in the 3000 to 5000 ppm range on a dry solids basis.

Moro, N.` Jha, M.C.

1997-09-29

424

A non-immersed induction conductivity system for controlling supersaturation in corrosive media: the case of gibbsite crystals agglomeration in Bayer liquors  

NASA Astrophysics Data System (ADS)

Agglomeration of gibbsite Al(OH) 3 crystallites is an important stage of the Bayer process, aiming at increasing the initial size of the particles. In the present work, a semi-continuous crystallizer working at constant and imposed supersaturation, and equipped with an automatic withdrawal system was developed to study the agglomeration of gibbsite crystals in supersaturated Bayer liquors. The liquor conductivity was measured using an induction conductivity system placed around the crystallizer, the conductivity regulation being used to work at constant supersaturation. Using this system allowed one to work with both a small crystallizer and a highly corrosive and abrasive suspension of gibbsite in a five molar caustic soda solution at 70°C. Analyses of the withdrawals were carried out with an Elzone particle counter, in order to draw {N(t)}/{N(0) = f(t)} plots, representing the decrease of crystal number with time, due to agglomeration.

Seyssiecq, I.; Veesler, S.; Boistelle, R.

1996-11-01

425

Engineering development of advanced physical fine coal cleaning for premium fuel applications. Task 6 -- Selective agglomeration laboratory research and engineering development for premium fuels  

SciTech Connect

The primary goal of this project is the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope included laboratory research and benchscale testing on six coals to optimize these processes, followed by the design, construction, and operation of a 2 t/hr process development unit (PDU). The project began in October, 1992, and is scheduled for completion by September 1997. This report represents the findings of Subtask 6.5 Selective Agglomeration Bench-Scale Testing and Process Scale-up. During this work, six project coals, namely Winifrede, Elkhorn No. 3, Sunnyside, Taggart, Indiana VII, and Hiawatha were processed in a 25 lb/hr continuous selective agglomeration bench-scale test unit.

Moro, N.; Jha, M.C.

1997-06-27

426

Oil on the Ocean  

NSDL National Science Digital Library

Students learn about oil spills and their environmental and economic effects. They experience the steps of the engineering design process as they brainstorm potential methods for oil spill clean-up, and then design, build, and re-design oil booms to prevent the spread of oil spills. During a reflective session after cleaning up their oil booms, students come up with ideas on how to reduce oil consumption to prevent future oil spills.

Integrated Teaching And Learning Program

427

Interferometric oil-spill detection system  

NASA Astrophysics Data System (ADS)

Oil spillage in a body of water has been of great environmental concern. We present in this paper an automatic oil-spill detection system, which employs thin-film and wavefront-splitting interference techniques to determine the existence of surface oil or oil drops in water. Two independent automatic decision-making systems have been built to provide a reliable means of oil-spill detection. Initially a LabVIEWTM computer code and a charge- coupled-device camera were employed to discern and monitor the interference fringes generated from oil slicks. The LabVIEW imaging system was then replaced by a compact and low-cost imaging circuit that functions reliably in a buoy with relatively low power consumption.

Huang, Yen-Chieh; Liang, U. C.

2001-05-01

428

Midnight Oil  

E-print Network

Posted originally on the Archive of Our Own at http://archiveofourown.org/works/53751. Rating: General Audiences Archive Warning: No Archive Warnings Apply Category: F/M Fandom: Mina de Malfois Relationship: Mina de Malfois/Josh Amos Character: Josh... Amos, Mina de Malfois - Character Additional Tags: minaverse Stats: Published: 2010-01-20 Words: 840 Midnight Oil by Kadorienne Summary "RPF" about Josh Amos and Mina de Malfois by someone who buys their PR. Mina de Malfois seldom neglected her beauty...

2010-01-20

429

Oil damage  

SciTech Connect

This book presents the results of a series of studies designed to determine the extent and magnitude of the effects of the Exxon Valdez oil spill on marine mammals, particularly sea otters. A third of the book focuses on studies that quantify population-level impacts, with much of the remainder focusing on behavioral, pathologic, or toxicologic studies designed to understand how petroleum hydrocarbons negatively affect free ranging marine animals.

Helm, R.C. [Fish and Wildlife Service, Portland, OR (United States)

1995-03-31

430

Influence of Electrical Discharges in Oil and Combinations of Oil and Paper  

Microsoft Academic Search

Charge or RIV techniques for corona (partial discharge)have been used in factory tests of high-voltage oil-filled equipment.Such tests have also been used in the field. More recently, measurementsof evolved gas have been made as well.In the laboratory, the effect of corona in oil has been determinedlargely by measuring gas evolution using the Pirelli test, in whichdischarges take place in oil

KENNETHN. MATHES

1976-01-01

431

Nonisothermal determination of the intrinsic kinetics of oil generation from oil shale  

Microsoft Academic Search

A nonisothermal technique using various heating rates has been applied to the determination of the intrinsic kinetics of oil generation from oil shale. From an engineering standpoint the rate of oil generation can adequately be described by overall first-order kinetics with a constant activation energy of 199 kJ\\/mol. Various methods are applied to the determination of the kinetics parameters. The

S.-M. Shih; H. Y. Sohn

1980-01-01

432

Electronic engine oil dispenser  

SciTech Connect

An automatic engine oil dispenser and indicator is described which comprises: (a) means for sensing low engine oil pressure; (b) a reservoir storing a quantity of oil when the engine oil pressure is at a specified level; (c) means for indicating a low amount of the oil in the reservoir; and (d) an automatic check valve communicating with the reservoir. The check valve is responsive to engine oil pressure to open and allow unrestricted flow of the oil from the reservoir to the engine when the engine oil pressure falls below a specified level until the oil pressure in the engine rises back to the specified level thereby closing the valve.

Martin, C.E.; Spector, G.

1988-05-03

433

Impact of agglomeration and different dispersions of titanium dioxide nanoparticles on the human related in vitro cytotoxicity and genotoxicity.  

PubMed

The published results on nanoparticles cytotoxicity and genotoxicity such as titanium dioxide nanoparticles (TiO(2) NPs) are inconsistent, and often conflicting and insufficient. Since different parameters may have impact on the toxicity results, there is need to lay stress on detailed characterization of NPs and the use of different testing conditions for assessment of NPs toxicity. In order to investigate whether dispersion procedures influence NP cytotoxicity and genotoxicity, we compared two protocols giving TiO(2) NP dispersions with different stability and agglomeration states. Detailed primary and secondary characteristics of both TiO(2) NP dispersions in culture media were carried out before toxicological testing; TK6 human lymphoblast cells, EUE human embryonic epithelial cells and Cos-1 monkey kidney fibroblasts were used to assess cytotoxicity (by trypan blue exclusion, proliferation activity and plating efficiency assays) and genotoxicity (by the comet assay). DNA strand breaks were detected by the alkaline comet assay. DNA oxidation lesions (especially 8-oxo-7,8-dihydroguanine, 8-oxoG) were measured with a modified comet assay including incubation with specific repair enzyme formamidopyrimidine DNA glycosylase (FPG). The TiO(2) NPs dispersion with large agglomerates (3 min sonication and no serum in stock solution) induced DNA damage in all three cell lines, while the TiO(2) NPs dispersed with agglomerates less than 200 nm (foetal serum in stock solution and sonication 15 min) had no effect on genotoxicity. An increased level of DNA oxidation lesions detected in Cos-1 and TK6 cells indicates that the leading mechanism by which TiO(2) NPs trigger genotoxicity is most likely oxidative stress. Our results show that the dispersion method used can influence the results of toxicity studies. Therefore at least two different dispersion procedures should be incorporated into assessment of cyto- and genotoxic effects of NPs. It is important, when assessing the hazard associated with NPs, to establish standard testing procedures and thorough strategies to consider the diverse conditions relevant to possible exposures. PMID:22277962

Magdolenova, Zuzana; Bilani?ová, Dagmar; Pojana, Giulio; Fjellsbø, Lise M; Hudecova, Alexandra; Hasplova, Katarina; Marcomini, Antonio; Dusinska, Maria

2012-02-01

434

Size-dependent cytotoxicity of silver nanoparticles in human lung cells: the role of cellular uptake, agglomeration and Ag release  

PubMed Central

Background Silver nanoparticles (AgNPs) are currently one of the most manufactured nanomaterials. A wide range of toxicity studies have been performed on various AgNPs, but these studies report a high variation in toxicity and often lack proper particle characterization. The aim of this study was to investigate size- and coating-dependent toxicity of thoroughly characterized AgNPs following exposure of human lung cells and to explore the mechanisms of toxicity. Methods BEAS-2B cells were exposed to citrate coated AgNPs of different primary particle sizes (10, 40 and 75 nm) as well as to 10 nm PVP coated and 50 nm uncoated AgNPs. The particle agglomeration in cell medium was investigated by photon cross correlation spectroscopy (PCCS); cell viability by LDH and Alamar Blue assay; ROS induction by DCFH-DA assay; genotoxicity by alkaline comet assay and ?H2AX foci formation; uptake and intracellular localization by transmission electron microscopy (TEM); and cellular dose as well as Ag release by atomic absorption spectroscopy (AAS). Results The results showed cytotoxicity only of the 10 nm particles independent of surface coating. In contrast, all AgNPs tested caused an increase in overall DNA damage after 24 h assessed by the comet assay, suggesting independent mechanisms for cytotoxicity and DNA damage. However, there was no ?H2AX foci formation and no increased production of intracellular reactive oxygen species (ROS). The reasons for the higher toxicity of the 10 nm particles were explored by investigating particle agglomeration in cell medium, cellular uptake, intracellular localization and Ag release. Despite different agglomeration patterns, there was no evident difference in the uptake or intracellular localization of the citrate and PVP coated AgNPs. However, the 10 nm particles released significantly more Ag compared with all other AgNPs (approx. 24 wt% vs. 4–7 wt%) following 24 h in cell medium. The released fraction in cell medium did not induce any cytotoxicity, thus implying that intracellular Ag release was responsible for the toxicity. Conclusions This study shows that small AgNPs (10 nm) are cytotoxic for human lung cells and that the toxicity observed is associated with the rate of intracellular Ag release, a ‘Trojan horse’ effect. PMID:24529161

2014-01-01