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1

Oil agglomeration process  

SciTech Connect

A method is described for producing agglomerate particles from aqueous slurries containing from about 10 to about 40 weight percent solids. The solids are comprised of finely divided carbonaceous solids and finely divided inorganic solids. By mixing the aqueous slurry with oil in a first mixing zone a mixture is formed and thereafter further agitating the mixture results in at least one other mixing zone to produce agglomerate particles containing the carbonaceous solids and the oil and recovering the product agglomerate particles. An improvement is described comprising (A) separating finely divided inorganic solids from the aqueous slurry after removal of the product agglomerate particles therefrom; (B) thereafter separating smaller agglomerates of carbonaceous solids and oil from the aqueous slurry after separation of the product agglomerate particles and the inorganic solids therefrom; and (C) recycling the smaller agglomerates to the second mixing zone.

Halvorsen, W. J.

1981-02-03

2

POC-Scale Testing of Oil Agglomeration Techniques and Equipment for Fine Coal Processing  

SciTech Connect

The objective of this project is to develop and demonstrate a Proof-of-Concept (POC) scale oil agglomeration technology capable of increasing the recovery and improving the quality of fine coal strearrts. Two distinct agglomeration devices will be tested, namely, a conventional high shear mixer and a jet processor. To meet the overall objective an eleven task work plan has been designed. The work ranges from batch and continuous bench-scale testing through the design, commissioning and field testing of POC-scale agglomeration equipment.

None

1998-11-12

3

POC-scale testing of oil agglomeration techniques and equipment for fine coal processing  

SciTech Connect

This report covers the technical progress achieved from April 1, 1998 to June 30, 1998 on the POC-Scale Testing of Oil Agglomeration Techniques and Equipment for Fine Coal Processing. Continuous bench-scale runs were carried out with Luscar Mine coal. The main objectives were to optimize process conditions for a proposed jet processor and to compare its performance with a standard high-shear mixer. A total of three runs consisted of 15 testing periods was carried out. Both conditioning devices performed very well with combustible matter recovery exceeding 96%. Slightly higher coal recovery was observed for high-shear mixer, while lower ash contents were achieved when jet processor was used for coal conditioning. During the current reporting period work has been continued and completed on the engineering and design package of a 3 t/h POC-scale agglomeration unit. Preliminary design package prepared by Thermo Design Engineering, a subcontractor to this project, was submitted to DOE for revision and approval.

W. Pawlak; K. Szymocha

1998-08-01

4

POC-SCALE TESTING OF OIL AGGLOMERATION TECHNIQUES AND EQUIPMENT FOR FINE COAL PROCESSING  

SciTech Connect

This report covers the technical progress achieved from October 1, 1997 to December 31, 1997 on the POC-Scale Testing of Oil Agglomeration Techniques and Equipment for Fine Coal Processing project. Experimental test procedures and the results related to the processing of coal fines originating from process streams generated at the Shoal Creek Mine preparation plant, owned and operated by the Drummond Company Inc. of Alabama, are described. Two samples of coal fines, namely Cyclone Overflow and Pond Fines were investigated. The batch test results showed that by applying the Aglofloat technology a significant ash removal might be achieved at a very high combustible matter recovery: · for the Cyclone Overflow sample the ash reduction was in the range 50 to 55% at combustible matter recovery about 98% · for the Pond Fines sample the ash reduction was up to 48% at combustible matter recovery up to 85%. Additional tests were carried out with the Alberta origin Luscar Mine coal, which will be used for the parametric studies of agglomeration equipment at the 250 kg/h pilot plant. The Luscar coal is very similar to the Mary Lee Coal Group (processed at Shoal Creek Mine preparation plant) in terms of rank and chemical composition.

NONE

1998-01-01

5

POC-scale testing of oil agglomeration techniques and equipment for fine coal processing  

SciTech Connect

This report covers the technical progress achieved from January 1, 1998 to April 31, 1998 on the POC-Scale Testing of Oil Agglomeration Techniques and Equipment for Fine Coal Processing. Experimental work was carried out with two coal fines. One sample originated from pond (Drummond Pond Fines) while the second was pulverized Luscar Mine coal. Both samples were tested at the laboratory batch-scale while only Luscar Mine Coal was processed on the 250 kg/h continuous system. Significant progress was made on optimization of process conditions for Pond Fines. The test results showed that ash could be reduced by about 42% at combustible recovery exiting 94%. It was also found that pond fines required significantly longer conditioning time than freshly pulverized run of mine coal. Continuous bench-scale testing carried out with Luscar Mine coal included rod mill calibration, plant equipment and instrumentation check-up, and parametric studies. Compared with batch-scale tests, the continuous bench-scale process required more bridging oil to achieve similar process performance. During the current reporting period work has been commenced on the final engineering and preparation of design package of 3t/h POC-scale unit.

W. Pawlak; K. Szymocha

1998-04-01

6

Oil agglomeration of oxidized coal  

SciTech Connect

The effect of surface oxidation on the oil agglomeration characteristics of coal has not been well documented, although it is known that lower rank, hydrophilic coals are more difficult to agglomerate than higher rank, hydrophobic coals. In order to contribute to a better understanding of the effect of surface oxidation, the present investigation was undertaken. Upper Freeport bituminous coal from Pennsylvania was selected for the study because it is normally hydrophobic and readily agglomerated. A surface oxidation treatment was applied to this coal to see how it would affect the agglomeration characteristics of the material. In determining these characteristics, samples of oxidized and unoxidized coal fines were suspended in water and agglomerated with pure aliphatic hydrocarbons. Both the pH of the suspension and amount of added oil were varied, and in some cases various surfactants were added to the suspension. The electrokinetic properties of the coal particles and oil droplets were also determined to gain further insight. 12 refs., 10 figs.

Sadowski, Z.; Venkatadri, R.; Druding, J.M.; Markuszewski, R.; Wheelock, T.D.

1986-01-01

7

POC-SCALE TESTING OF OIL AGGLOMERATION TECHNIQUES AND EQUIPMENT FOR FINE COAL PROCESSING  

SciTech Connect

This report covers the technical progress achieved from July 01, 1997 to September 30, 1997 on the POC-Scale Testing Agglomeration Techniques and Equipment for Fine Coal Processing project. Experimental procedures and test data for recovery of fine coal from coal fines streams generated at a commercial coal preparation plant are described. Two coal fines streams, namely Sieve Bend Effluent and Cyclone Overflow were investigated. The test results showed that ash was reduced by more than 50% at combustible matter recovery levels exceeding 95%.

NONE

1998-01-01

8

Critical solution surface tension for oil agglomeration  

Microsoft Academic Search

This paper presents the effect of surface tension of solution used as medium for the oil agglomeration of minerals. Naturally occurring hydrophobic and hydrophilic minerals are used in this study. It was determined that the oil agglomeration recoveries of these minerals decreased with decreasing solution surface tension and the oil agglomeration process of the mineral did not occur below a

A. Ozkan; S. Aydogan; M. Yekeler

2005-01-01

9

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

10

POC-scale testing of oil agglomeration techniques and equipment for fine coal processing. Technical report number 2, October 1--December 31, 1995.  

National Technical Information Service (NTIS)

The objective of this project is to develop and demonstrate a Proof-of-Concept (POC) scale oil agglomeration technology capable of increasing the recovery and improving the quality of fine coal streams. Two distinct agglomeration devices will be tested, n...

1996-01-01

11

Pyrite suppression in oil agglomeration of coal  

SciTech Connect

The oleophilicity of pyrite frequently interferes with the separation of coal and pyrite in aqueous suspensions by selective agglomeration with oil. To solve this problem, a search has been conducted for suitable agglomeration suppressants for oleophilic pyrite, and a number of promising materials have been found. Of special interest is a group of organic compounds which is the subject of this report. These compounds contain both sulfhydryl group (-SH) and a hydrophilic group such as a carboxyl or sulfonic acid group. Thioglycolic acid (HSCH{sub 2}COOH) is an example. This material has been used to suppress the recovery of pyrite in froth flotation systems where particle separation is also controlled by surface properties. For the present study, both high-grade mineral pyrite and coal-derived pyrite were sulfurized by treatment with a freshly acidified solution of sodium sulfide which made the pyrites highly oleophilic. The treated pyrites were used subsequently to test a number of potential agglomeration suppressants. The effect on agglomeration was determined by monitoring changes in the turbidity of an agitated pyrite suspension as increasing amounts of heptane were introduced. A decrease in turbidity was indicative of agglomeration, whereas an increase in turbidity was indicative of particle an/or oil dispersion. Additional experiments were conducted in which an artificial mixture of Illinois No. 6 coal and sulfurized mineral pyrite was agglomerated with heptane after being conditioned with a pyrite suppressant. The agglomerates were recovered by screening and then analyzed to determine the effectiveness of the suppressant. 7 refs., 1 fig., 1 tab.

Drzymala, J.; Markuszewski, R.; Wheelock, T.D.

1991-01-01

12

POC-scale testing of oil agglomeration techniques and equipment for fine coal processing. Quarterly report, July 1--September 30, 1997  

SciTech Connect

This report covers the technical progress achieved from July 1, 1997 to September 30, 1997 on the POC-Scale Testing Agglomeration Techniques and Equipment for Fine Coal Processing project. Experimental procedures and test data for recovery of fine coal from coal fines streams generated at a commercial coal preparation plant are described. Two coal fines streams, namely Sieve Bend Effluent and Cyclone Overflow were investigated. The test results showed that ash was reduced by more than 50% at combustible matter recovery levels exceeding 95%.

Ignasiak, B.; Pawlak, W.; Szymocha, K.

1997-12-31

13

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

14

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

15

Powder agglomeration patterns at acoustic driving observed by sonoluminescence technique  

NASA Astrophysics Data System (ADS)

A sonoluminescence (SL) technique gives a sensitive probe to detect spatial agglomeration patterns produced in powder mixtures subjected to acoustically driven plate. Studies of the surface-integrated SL intensity with increasing driving amplitude yield data about variations of the packing density on the surface of vibrating powders. Imaging of spatial distributions of the SL intensity enables direct measurement of the size of agglomeration patterns. The size of the patterns is found to be ~102 ?m in a 3-?m-sized powder at a driving frequency of about 4 MHz. The distribution of the average sonoluminescence intensity across the pattern is attributed to the density gradient while rapid variations in the SL intensity across the pattern are suggested to give the particle velocity distribution within the pattern. The temporal changes of the SL intensity can be used to study time evolutions of dense powder arrangements.

Korotchenkov, O. A.; Goto, T.

1999-01-01

16

Coal recovery from coal fines cleaning wastes by agglomeration with vegetable oils: effects of oil type and concentration  

Microsoft Academic Search

The aim of this work was to obtain high calorific value products from coal fines cleaning wastes by agglomeration with vegetable oils. These residues are mainly being disposed of in dumps, causing important economic and environmental problems. Three Spanish coal fines wastes from different coal cleaning plants were agglomerated with crude and refined sunflower and soybean oils over a wide

Marta I Alonso; Adolfo F Valdés; Rosa M Mart??nez-Tarazona; Ana B Garcia

1999-01-01

17

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

18

Remediation of heavy metal contaminated solid wastes using agglomeration techniques  

Microsoft Academic Search

A process has been developed for the remediation of heavy metal contaminated, fine textured; solid wastes so that the treated material will meet EPA's TCLP and Total Extractable Metal Limits. The process involves the formation of strong aggregates using dry agglomeration methods. Remediation is achieved either by incorporating metal fixation agents into the agglomerates, or by leaching of heavy metal

A. Majid; S. Argue

2001-01-01

19

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

20

The investigation of coal–pyrite\\/lignite concentration and their separation in the artificial mixture by oil agglomeration  

Microsoft Academic Search

In this study, the concentration of coal–pyrite and lignite taken from Yozgat-Ayridam (Turkey) Coal Management was investigated by oil agglomeration.In the previous studies, the agglomeration of coal–pyrite was investigated using different bridging liquids (fuel oil, diesel oil and kerosene) and the combination of reagent (KEX, Acorga M5397)+kerosene. When using only bridging liquids, the agglomeration recovery of pyrite was very low.

Yakup Cebeci; ?brahim Sönmez

2002-01-01

21

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

22

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 ...

23

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

24

Experimental prediction of the agglomeration capability of waste vegetable oils (WVO) in relation to the recovery of coal from coal fines cleaning wastes (CFCW)  

Microsoft Academic Search

Coal fines cleaning wastes (CFCW) were agglomerated with samples of a vegetable oil heated at 150°C for 1–15 days. An agglomeration efficiency index (AEI) which variation depends on the oil agglomeration capability was calculated. Good linear correlations were attained between the AEI values and the viscosity, and the unsaturation degree of the oil monitored by FT–IR and 1H NMR. Based

Adolfo F. Valdés; M. Dolores González-Azpiroz; Carlos G. Blanco; Ana B. Garc?´a

2007-01-01

25

Desulfurization and de-ashing of a mixture of subbituminous coal and gangue minerals by selective oil agglomeration  

SciTech Connect

The aim of this study was to investigate desulfurization and de-ashing of a mixture of subbituminous coal and gangue minerals by the agglomeration method. For this purpose, experimental studies were conducted on a mixture containing subbituminous coal, pyrite, quartz and calcite. The effects of some parameters that markedly influence the effectiveness of selective oil agglomeration, such as solid concentration, pH, bridging liquid type and concentration, and depressant type and amount, were investigated. Agglomeration results showed that the usage of various depressants (Na{sub 2}SiO{sub 3}, FeCl3, corn starch, wheat starch) in the agglomeration medium has a positive effect on the reduction of ash and total sulfur content of agglomerates. It was found that an agglomerate product containing 3.03% total sulfur and 25.01% ash with a total sulfur reduction of 56.71% was obtained from a feed that contained 7% total sulfur and 43.58% ash when FeCl{sub 3} was used in the agglomeration medium.

Ayhan, F.D. [Dicle University, Diyarbakir (Turkey). Dept. of Mining Engineering

2009-11-15

26

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

27

Development of a gas-promoted oil agglomeration process. Technical progress report, April 1, 1994--June 30, 1994  

SciTech Connect

The overall purpose of this research project is to carry out the preliminary laboratory-scale development of a gas-promoted, oil agglomeration process for cleaning coal using model mixing systems. The design and construction of a model mixing system for conducting oil agglomeration tests were reported previously as well as the results of a series of calibration and shakedown tests. The system consists of a flat bottom tank which is fitted with four vertical baffles, a cover, and a turbine agitator. The tank has an inside diameter of 15.24 cm (6.0 in.), height of 15.24 cm (6.0 in.), and net volume of 2.87 L. The tank is connected to a photometric dispersion analyzer so that the turbidity of a coal particle suspension undergoing agglomeration can be monitored. Measuring the turbidity of a particle suspension requires application of the Beer-Lambert law. However, since this law applies for dilute suspensions, it is questionable whether or not it applies to the somewhat more concentrated coal suspensions required for the present project. Therefore, to determine the law`s applicability, a series of turbidity measurements was conducted on particle suspensions which varied in particle concentration over a wide range, and the results were analyzed to see how well they agreed with the law. To determine the effect of air in promoting the oil agglomeration of coal particles in an aqueous suspension, a number of agglomeration tests were conducted with the model mixing system. Finely ground Pittsburgh No. 8 coal was used for these tests, and the amount of air present was controlled carefully. The agglomeration process was monitored by observing the change in turbidity of the system.

Wheelock, T.D.; Drzymala, J.; Zhang, F.; Nelson, C.

1994-09-01

28

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

PubMed Central

The purpose of this research was to obtain directly compressible agglomerates of naproxen containing disintegrant by spherical crystallization technique. Acetone–water containing hydroxypropyl celloluse (HPC) and disintegrant was used as the crystallization system. In this study croscarmellose sodium (Ac–Di–Sol) was employed as disintegrant. The agglomerates were characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (XRPD), and scanning electron microscopy and were evaluated for flow, packing and tableting properties and drug release. The growth of particle size and the spherical form of the agglomerates resulted in formation of products with good flow and packing properties. The improved compaction properties of the agglomerated crystals were due to their fragmentation occurred during compression. DSC and XRPD studies showed that naproxen particles, crystallized in the presence of HPC and Ac–Di–Sol did not undergo structural modifications. The dissolution rate of naproxen from tablets made of naproxen–(Ac–Di–Sol) agglomerates was enhanced significantly because of including the disintegrant in to the particles. This was attributed to an increase in the surface area of the practically water insoluble drug is exposed to the dissolution medium. In conclusion the spherical crystallization technique developed in this study is suitable for obtaining agglomerates of drug with disintegrant.

Nokhodchi, A.

2008-01-01

29

On the utilization of waste vegetable oils (WVO) as agglomerants to recover coal from coal fines cleaning wastes (CFCW)  

Microsoft Academic Search

Coal fines cleaning wastes (CFCW) from two different Spanish coal cleaning plants were agglomerated with waste vegetable oils (WVO) of household origin over a wide range of oil concentration with the aim of recovering high-calorific value\\/low-ash content coal. The results were evaluated in terms of organic matter recovery (OMR) and ash rejection (AR) from CFCW. In addition to the WVO

Adolfo F. Valdés; Ana B. Garcia

2006-01-01

30

Measurement of agglomerate strength distributions in agglomerated powders  

Microsoft Academic Search

A new technique for measuring the strength distributions of powder agglomerates involves the use of a calibrated ultrasonic sound field. Agglomerate strength distributions were measured for a variety of yttria and yttria-stabilized zirconia powders. Different preparation methods were used to obtain powders containing agglomerates with different characteristics. Special yttria powders containing agglomerates of 0.1 microns, spherical, monosize spheres were also

M. Ciftcioglu

1987-01-01

31

Gas-hydrate formation, agglomeration and inhibition in oil-based drilling fluids for deep-water drilling  

Microsoft Academic Search

One of the main challenges in deep-water drilling is gas-hydrate plugs, which make the drilling unsafe. Some oil-based drilling fluids (OBDF) that would be used for deep-water drilling in the South China Sea were tested to investigate the characteristics of gas-hydrate formation, agglomeration and inhibition by an experimental system under the temperature of 4 °C and pressure of 20 MPa,

Fulong Ning; Ling Zhang; Yunzhong Tu; Guosheng Jiang; Maoyong Shi

2010-01-01

32

Investigation of the effect of agglomeration time, pH and various salts on the cleaning of Zonguldak bituminous coal by oil agglomeration  

Microsoft Academic Search

In this study, the effects of bridging liquid concentration, agglomeration time, pH and various salts on the combustible recovery and ash contents of the agglomerated products have been investigated. Kerosene was used as bridging liquid. The optimum values of kerosene concentration, pH and agglomeration time have been determined as 20wt%, 7.5 and 15min, respectively. Metallic salts, such as FeSO4, NaCl,

Yakup Cebeci; U?ur Ulusoy; Selma ?im?ek

2002-01-01

33

Measurement of Agglomerate Strength Distributions in Agglomerated Powders.  

National Technical Information Service (NTIS)

A new technique for measuring the strength distributions of powder agglomerates involves the use of a calibrated ultrasonic sound field. Agglomerate strength distributions were measured for a variety of yttria and yttria-stabilized zirconia powders. Diffe...

M. Ciftcioglu

1987-01-01

34

Effects of oil concentration and particle size on the cleaning of Spanish high-rank coals by agglomeration with n-heptane  

Microsoft Academic Search

The response of three high-ash Spanish anthracites to agglomeration with n-heptane was evaluated by measuring the organic matter recovery, ash rejection and pyritic sulfur rejection. The influence of oil concentration and coal particle size on the agglomeration results was investigated. The combustible recoveries of these coals increased to a maximum as the n-heptane concentration is raised, and then decreased. Ash

Ana B. Garcia; José M. G. Vega; M. Rosa Martinez-Tarazona

1995-01-01

35

Breakage patterns of agglomerates  

Microsoft Academic Search

The experimental information available in the literature regarding the patterns of breakage of agglomerate materials is scarce, particularly in dynamic loading. The primary objective of this paper is to present our findings on the breakage patterns of the agglomerates and the interparticle bond. A high-speed digital video imaging technique is used here to gain an insight into the impact behaviour

Jesús Subero; Mojtaba Ghadiri

2001-01-01

36

Oil Sampling Techniques.  

National Technical Information Service (NTIS)

Sampling of oil in the environment, depending upon the thickness of the slick, can present certain operational problems, most paramount of which is the collection of an adequate volume of sample required for identification by chemical analyses. Several ba...

1969-01-01

37

An Image Analysis Technique For Assessing Particle Size And Agglomeration Tendency Of Slurries  

Microsoft Academic Search

Understanding the time-dependent behavior and size of particulate systems, specifically, particles in abrasive slurries, is a key part of chemical mechanical polishing (CMP). Microscopy and image analysis enables both qualitative and quantitative analysis of particle interaction behavior in diluted samples of such particulate suspensions. A technique using microscopy and image analysis has been developed specific to the analysis of suspensions

Susan R. Machinski; Kathleen A. Richardson; Aristide Dogariu

38

Measurement of agglomerate strength distributions in agglomerated powders  

NASA Astrophysics Data System (ADS)

A new technique for measuring the strength distributions of powder agglomerates involves the use of a calibrated ultrasonic sound field. Agglomerate strength distributions were measured for a variety of yttria and yttria-stabilized zirconia powders. Different preparation methods were used to obtain powders containing agglomerates with different characteristics. Special yttria powders containing agglomerates of 0.1 microns, spherical, monosize spheres were also prepared. BET surface area, tap density, pressed density, compaction curves, and mercury intrusion curves were also obtained. The powders were pressed and sintered, and the sintered density measured for each pellet. Smooth curves could be drawn when agglomerate strength was plotted against sintered density; the sintered density of the powders also could be ranked directly according to the strength of the agglomerates in each powder. Except for the model yttria powders containing monosize spherical particles, there was no correlation between sintered density and any other measured powder parameter. For this model powder, most of measured powder parameters correlated directly with sintered density, in almost textbook fashion. It was also possible, using these model powders, to isolate the effect of agglomerate strength on sintered density by holding all other powder characteristics constant.

Ciftcioglu, M.

1987-08-01

39

New production techniques for Alberta oil sands  

SciTech Connect

Low world oil prices represent a serious threat to expanded commercial development of the Canadian oil sands in the near term, as they do to all of the higher cost alternatives to crude oil such as oil shales and coal liquefaction. Nonetheless, research and field testing of new technology for production of oil from oil sands are being pursued by industry and government in Alberta. New production technology is being developed in Canada to produce synthetic oil from the vast resources of bitumen trapped in the oil sands and bituminous carbonates of northern Alberta. This technology includes improved methods of mining, extraction, and up-grading of bitumen from near-surface deposits as well as new drilling and production techniques for thermal production of bitumen from the more deeply buried reservoirs. Of particular interest are the cluster drilling methods designed to reduce surface disturbance and the techniques for horizontal drilling of wells from underground tunnels to increase the contact of injection fluids with the reservoir. The history of oil sands technology development, the new drilling technology, and synthetic crude oil conversion are briefly described. 17 references.

Carrigy, M.A.

1986-12-19

40

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

41

Oil spill cleanup using vacuum technique  

Microsoft Academic Search

A vacuum technique is established for oil spill cleanup. It consists of environmental tank, oil-collecting unit, vacuum system, and air distributors. The vacuum technique is found very effective under all possible operating conditions. Several operating parameters are investigated such as hole arrangement (vertical and horizontal slots), air distributors location (one-side and two-sides strategies), air volumetric flow rate over the range

Mazmdouh T Ghannam; Omar Chaalal

2003-01-01

42

Mode-switching: a new technique for electronically varying the agglomeration position in an acoustic particle manipulator.  

PubMed

Acoustic radiation forces offer a means of manipulating particles within a fluid. Much interest in recent years has focussed on the use of radiation forces in microfluidic (or "lab on a chip") devices. Such devices are well matched to the use of ultrasonic standing waves in which the resonant dimensions of the chamber are smaller than the ultrasonic wavelength in use. However, such devices have typically been limited to moving particles to one or two predetermined planes, whose positions are determined by acoustic pressure nodes/anti-nodes set up in the ultrasonic standing wave. In most cases devices have been designed to move particles to either the centre or (more recently) the side of a flow channel using ultrasonic frequencies that produce a half or quarter wavelength over the channel, respectively. It is demonstrated here that by rapidly switching back and forth between half and quarter wavelength frequencies - mode-switching - a new agglomeration position is established that permits beads to be brought to any arbitrary point between the half and quarter-wave nodes. This new agglomeration position is effectively a position of stable equilibrium. This has many potential applications, particularly in cell sorting and manipulation. It should also enable precise control of agglomeration position to be maintained regardless of manufacturing tolerances, temperature variations, fluid medium characteristics and particle concentration. PMID:19709711

Glynne-Jones, Peter; Boltryk, Rosemary J; Harris, Nicholas R; Cranny, Andy W J; Hill, Martyn

2009-08-04

43

Effect of colloidal silica addition on the formation of porous spherical ?-calcium orthophosphate agglomerates by spray pyrolysis technique  

Microsoft Academic Search

The effect of colloidal silica (SiO2; CS) addition on the formation of porous spherical ?-calcium orthophosphate (?-Ca3(PO4)2; ?-TCP) agglomerates has been examined. The starting powder was prepared by the spray pyrolysis of calcium phosphate (Ca\\/P ratio = 1.50) solution containing 0.9 mol?dm-3 Ca(NO3)2, 0.6 mol?dm-3 (NH4)2HPO4, CS (mean particle size; 14, 24 and 39 nm) and concentrated HNO3 at 600°C,

Kiyoshi ITATANI; Ari OOE; Ian J. DAVIES; Tomohiro UMEDA; Yoshiro MUSHA; Seiichiro KODA

2009-01-01

44

Silica nanoparticle sols. Part 3: Monitoring the state of agglomeration at the air/water interface using the Langmuir-Blodgett technique.  

PubMed

Langmuir-Blodgett films were prepared at the air/water interface from dispersions of hydrophilic and partially, hydrophobically modified industrially manufactured silica nanoparticles. The hydrophilic particles featured expanded, fairly easily compressible, surface pressure (pi)-area (A) isotherms with well defined collapse pressures which appeared to be caused by the formation of loosely structured agglomerates which exhibited elastic behavior at low surface pressure and inelastic behavior at high surface pressure. Lateral electrostatic interparticle interactions seemingly played an important role in this hydrophilic system. This contrasted with the hydrophobically modified particles which were more difficult to disperse in the ethanol/chloroform spreading solvent and appeared to be in the semi-agglomerated state at low surface pressures and exhibited a more difficult to compress compacted film. Both types of particulate films were shown to be sensitive to the spreading environment and changes in pH were found to increase particle agglomeration which drastically reduced the particulate area for the hydrophilic sol but less so, in the case of the moderately hydrophobically modified sol. In general, the LB technique proved to be a useful method to monitor changes in the state of aggregation of nanosized silica particles at the air/water interface. These results also appear to give some support of our ideas, presented in earlier publications in which it was suggested that the major role of the hydrophobically modified hydrophilic particles in foaming was to produce an aggregated particulate film surrounding the air/water interface which provides a physical barrier preventing coalescence of bubbles. PMID:19520375

Blute, Irena; Pugh, Robert J; van de Pas, John; Callaghan, Ian

2009-04-21

45

POC-scale testing of oil agglomeration techniques and equipment for fine coal processing  

SciTech Connect

The information presented in this manual is solely for the purpose of operating the POC-scale equipment for fine coal processing as described herein. This manual provides a general description of the process technology and guidelines for plant operating procedures. It is intended for use by the operators and maintenance personnel who will be responsible for the operations of the plant. No attempt should be made to operate the plant until the principles of the process and operating instructions contained in this manual are fully understood. Operating personnel should thoroughly familiarize themselves with all processing equipment prior to commencing plant operation. All equipment is skid mounted to provide a self-contained unit. The dimensions of the unit are comply with standard guidelines. A minimum distance of 2 feet is provided between equipment for walkway and maintenance.

W. Pawlak; K. Szymocha

1999-07-01

46

Large urban agglomerations of the Soviet Union.  

PubMed

The study of urban agglomerations in the USSR is discussed, with a focus on their basic framework and role in settlement and on the various techniques used to define such agglomerations. "The present paper envisages a minimum population of 250,000 for the core city (or cities), maximum travel time of 1.5 to 2 hours to the core city, and a minimum value for a 'development coefficient' reflecting the population of the agglomeration and its structure in terms of urban places. The networks of agglomerations that existed at the time of the 1959 and 1970 censuses are analyzed and compared. The urban agglomerations are grouped into five classes of development levels and into three classes of growth rates. Intensive and extensive growth factors are discussed." PMID:12338888

Polyan, P M

1982-12-01

47

New production techniques for Alberta oil sands  

Microsoft Academic Search

Low world oil prices represent a serious threat to expanded commercial development of the Canadian oil sands in the near term, as they do to all of the higher cost alternatives to crude oil such as oil shales and coal liquefaction. Nonetheless, research and field testing of new technology for production of oil from oil sands are being pursued by

M. A. CARRIGY

1986-01-01

48

New Production Techniques for Alberta Oil Sands  

Microsoft Academic Search

Low world oil prices represent a serious threat to expanded commercial development of the Canadian oil sands in the near term, as they do to all of the higher cost alternatives to crude oil such as oil shales and coal liquefaction. Nonetheless, research and field testing of new technology for production of oil from oil sands are being pursued by

Maurice A. Carrigy

1986-01-01

49

Detection of Oil in Water by a Flame Emission Technique.  

National Technical Information Service (NTIS)

A flame emission technique and basic instrument design is presented for measuring low concentrations of oil in oil-contaminated water. The flame emission instrument developed in this report would be useful as a detector for petroleum oils. The flame emiss...

M. Pragar D. Stainken

1981-01-01

50

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

51

Secondary oil recovery techniques improve remediation projects  

SciTech Connect

The petroleum industry has successfully developed sophisticated oil recovery technologies that could be used for effective contaminant removal from soil and/or groundwater. In enhanced recovery, the residual oil is mobilized through injection of a solvent that is miscible with oil. Soil vapor extraction takes advantage of the highly volatile nature of VOCs in air and the relative ease of moving air through the unsaturated zone to effectively remove VOCs from the soil. A similar approach can be used for groundwater decontamination.

Aminian, K.; Ameri, S.

1996-01-01

52

Techniques for evaluating heavy oil cracking catalysts  

Microsoft Academic Search

Commercial performance of heavy oil cracking catalysts is influenced by diffusivity of heavy oil components through the catalyst matrix, catalyst activity and selectivity for cracking heavier portion of the feed, presence of feed contaminant metals and Conradson carbon. Effects of contaminant metals and Conradson carbon have been previously investigated. This study examines effects of reactant diffusivity and feed crackability. Portions

G. W. Young; K. Rajayopalan

1983-01-01

53

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

54

New technique for oil backstreaming contamination measurements  

NASA Astrophysics Data System (ADS)

The backstreaming contamination in the Space Power Facility, Ohio, was measured using small size clean silicon wafers as contamination sensors placed at all measurement sites. Two ellipsometric models were developed to measure the oil film with the contamination film refractive index of DC 705: a continuous, homogeneous film and islands of oil with the islands varying in coverage fraction and height. The island model improved the ellipsometric analysis quality parameter by up to two orders of magnitude. The continuous film model overestimated the oil volume by about 50 percent.

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

1992-08-01

55

New Technique for Oil Backstreaming Contamination Measurements.  

National Technical Information Service (NTIS)

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 impo...

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

1991-01-01

56

New Technique for Oil Backstreaming Contamination Measurements.  

National Technical Information Service (NTIS)

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 impo...

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

1993-01-01

57

Robust Satellite Techniques (RST) for Oil Spill Detection and Monitoring  

Microsoft Academic Search

Satellite remote sensing is an useful tool supporting the management of marine technological hazards, especially for what concern oil discharge. Nowadays, the most reliable satellite techniques are based on SAR (Synthetic Aperture Radar) active sensors operating in the microwave region of the electromagnetic (EM) spectrum. Such methods (even if not in whatever wind condition), assure good sensitivity for oil spill

Daniele Casciello; T. Lacava; N. Pergola; V. Tramutoli

2007-01-01

58

Improved Hydraulic Pressure Treatment Techniques For Oil-Well Stimulation  

Microsoft Academic Search

Oil-soluble, water-insoluble diverting agents have been used to improve the effectiveness of hydraulic pressure treatments of oil wells. Successful applications have been made in hydraulic fracturing and in pressure acidizing as well as lost circulation control in drilling and workover operations. This technique results not only in more effective treatments but also in little or no formation damage because of

D. J. Watanabe; M. M. Ellis

1966-01-01

59

Micro-agglomerate flotation for deep cleaning of coal  

SciTech Connect

We are investigating the use of a hybrid process - Micro-agglomerate flotation - which is a combination of oil-agglomeration and froth flotation. 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 extract these micro-agglomerates from the water/dispersed-mineral phase. Since the floating units are agglomerates (about 30--50 [mu]m in size) rather than individual coal particles (1--10 [mu]m) the problems of froth overload and water/mineral carryover should be significantly alleviated. Micro-agglomerate flotation has considerable potential for the practical deep cleaning of coal on a commercial scale. In principle, it should be possible to achieve both high selectivity and high yield at reasonable cost. The process requires only conventional, off-the-shelf equipment and reagent usage (oil, surfactants, etc.) should be small. 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 necessary to maintain precise control over the chemistry of the liquid phases in order to promote the interfacial reactions and interactions between phases necessary to ensure selectivity. Kinetics as well as thermodynamic factors may be critical in determining overall system response.

Chander, S.; Hogg, R.

1993-01-01

60

Techniques for Mixing Dispersants with Spilled Oil.  

National Technical Information Service (NTIS)

The effective use of some oil spill dispersants requires the addition of mixing energy to the dispersant-treated slick. Various methods of energy application have included the use of fire hose streams directed to the water surface, outboard motors mounted...

G. F. Smith

1978-01-01

61

Oil Filter Analysis Technique Research Program.  

National Technical Information Service (NTIS)

The objectives of this program were to select the most promising nondestructive method for determining the quantity of iron in a 3-micrometer aircraft type oil filter, and to design, fabricate, and test two prototype field-usable units which utilized the ...

R. H. Hollinger

1978-01-01

62

Technique for the determination of asphaltenes in crude oil residues  

SciTech Connect

Recently, the authors reported a method for the determination of saturates, aromatics, and resins in deasphaltened crude oil residues by high-performance liquid chromatography using a flame ionization detector. The present work describes a filtration technique for the determination of asphaltenes in crude oil residues using disposable Millex filters. This technique reduces the filtration, washing, and equilibration time needed for asphaltene determination. Six crude oil residues that varied widely in asphaltene content were used to evaluate the precision of this technique. The values obtained by Millex filters were compared to the values obtained by a conventional method using filter papers. Agreement between the two methods was very good. Several methods have been reported for the separation and determination of asphaltenes. Speight et al. made a survey of the different asphaltene procedures and conducted the experimental work to determine the optimum conditions for asphaltene separation and determination. The operating parameters recommended by Speight were used in this work.

Pearson, C.D.; Huff, G.S.; Gharfeh, S.G.

1986-12-01

63

Wintergreen oil: a novel method in Wheatley's trichrome staining technique.  

PubMed

Permanent staining of faecal smears by Wheatley's trichrome technique has been used by many scientists for the detection of parasites in the past and it was found to be highly sensitive. This study was conducted to evaluate the use of Wintergreen oil in comparison with xylene in Wheatley's trichrome staining technique, as the reference technique. In a blind comparison study, 500 collected faecal samples from aboriginal communities were examined. Wintergreen oil was found to be more superior than xylene as a clearing agent in the Wheatley's trichrome staining of polyvinyl alcohol-fixed faecal smears for the identification of intestinal protozoa. Elimination of toxic, carcinogenic, and fire hazards makes Wintergreen oil the preferred choice in routine parasitology examinations. PMID:22986100

Salleh, Fatmah Md; Anuar, Tengku Shahrul; Yasin, Azlin Mohd; Moktar, Norhayati

2012-08-17

64

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

65

A New Technique for Measurement of Oil Biodegradation  

Microsoft Academic Search

An active strain of anaerobic thermophilic bacteria was isolated from the environment of the United Arab Emirates. The strain, identified as Bacillus species, consists of two types—round and rod-shaped bacteria. This project studied the possibility of using these two types of bacteria for biodegradation of oil under elevated temperature conditions using a new method of measurement. Chemical and physical techniques

A. Y. Zekri; J. H. Abou-Kassem; S. A. Shedid

2009-01-01

66

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

2013-05-09

67

Thermal Characterization of Edible Oils by Using Photopyroelectric Technique  

NASA Astrophysics Data System (ADS)

Thermal properties of several edible oils such as olive, sesame, and grape seed oils were obtained by using the 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. Also, the back photopyroelectric configuration was used to obtain the thermal diffusivity of these oils; this thermal parameter was obtained by fitting the theoretical equation for this configuration, as a function of the sample thickness (called the thermal wave resonator cavity), to the experimental data. All measurements were done at room temperature. A complete thermal characterization of these edible oils was achieved by the relationship between the obtained thermal diffusivities and thermal effusivities with their thermal conductivities and volumetric heat capacities. The obtained results are in agreement with the thermal properties reported for the case of the olive oil.

Lara-Hernández, G.; Suaste-Gómez, E.; Cruz-Orea, A.; Mendoza-Alvarez, J. G.; Sánchez-Sinéncio, F.; Valcárcel, J. P.; García-Quiroz, A.

2013-05-01

68

Thermal Characterization of Edible Oils by Using Photopyroelectric Technique  

NASA Astrophysics Data System (ADS)

Thermal properties of several edible oils such as olive, sesame, and grape seed oils were obtained by using the 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. Also, the back photopyroelectric configuration was used to obtain the thermal diffusivity of these oils; this thermal parameter was obtained by fitting the theoretical equation for this configuration, as a function of the sample thickness (called the thermal wave resonator cavity), to the experimental data. All measurements were done at room temperature. A complete thermal characterization of these edible oils was achieved by the relationship between the obtained thermal diffusivities and thermal effusivities with their thermal conductivities and volumetric heat capacities. The obtained results are in agreement with the thermal properties reported for the case of the olive oil.

Lara-Hernández, G.; Suaste-Gómez, E.; Cruz-Orea, A.; Mendoza-Alvarez, J. G.; Sánchez-Sinéncio, F.; Valcárcel, J. P.; García-Quiroz, A.

2013-03-01

69

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.

Rothenbacher, Sonja; Messerer, Armin; Kasper, Gerhard

2008-01-01

70

Oil spill cleanup and protection techniques for shorelines and marshlands  

SciTech Connect

A major oil spill ends in contamination of coastal or inland shorelines and marshlands, with possible environmental and economic damage. Such damage can be significantly reduced if proper protection and cleanup actions are taken promptly. The book provides a systematic methodology that can be used to assess the threat or extent of contamination and to choose the most appropriate protection/cleanup procedures for each shoreline or marshland contamination event. It gives the field user guidlines to determine cost-effective protection, cleanup and restoration techniques for a given oil spill situation.

Breuel, A.

1981-01-01

71

Laboratory techniques for investigating recovery in heavy oil reservoirs  

SciTech Connect

Although general guidelines have been published in the literature for selecting the most suitable tertiary recovery technique for a given reservoir, the actual design of a commercial enhanced recovery scheme is a time- consuming and expensive process requiring computer simulations, experimental field pilots, and extensive laboratory tests. The objective of this work is to review laboratory testing procedures related to heavy oil recovery and to provide reservoir and production engineers with an insight into such procedures so that they may better appreciate their potentials and limitations. The topics discussed include characterization of stock tank oils, phase behavior measurements of oil/gas systems, measurements of relative permeability, and its temperature dependence and core tests for evaluation of CO/sub 2/ stimulation. 22 references.

Maini, B.; Sayegh, S.

1983-01-01

72

Silicone oil removal after rhegmatogenous retinal detachment: comparing techniques  

PubMed Central

Purpose To assess the outcome of silicone oil removal after rhegmatogenous retinal detachment (RRD) surgery, and to compare results of a two-port (infusion-extraction) versus a three-port (full vitrectomy) approach. Methods Primary outcome measure was the rate of redetachment. Secondary outcome measures were visual acuity, rate of intraoperative and postoperative epiretinal membrane removal and complications. Results We included 147 consecutive cases. There were 15 cases of giant retinal tear, 26 cases of RRD without proliferative vitreoretinopathy (PVR) and 106 cases of RRD with PVR. The overall redetachment rate after silicone oil removal was 17.7%. In the group treated with the two-port technique (n=95), the retina redetached in 16 cases (16.8%), and in the group treated with the three-port technique (n=52), redetachment occurred in 10 cases (19.2%). This difference was not statistically significant (P=0.717; ? 2-test). There was a significantly higher redetachment rate in cases with a short oil tamponade duration of <2 months. Conclusion We reconfirm a relatively high redetachment rate after silicone oil removal. The risk of redetachment is not lower with the three-port compared with the two-port approach.

Tan, H S; Dell'Omo, R; Mura, M

2012-01-01

73

Analysis of cold rolling oils by NMR and IR techniques  

SciTech Connect

A new technology has been developed based on infrared (IR) and nuclear magnetic resonance (NMR) spectroscopic techniques for the quantitation of various components in rolling oils without their prior separation. The IR method makes use of a curve-fitting approach in which the multicomponent mixtures with overlapping bands can be quantified without exhibiting isolated, characteristic frequencies for each component. Prior information about the nature and the type of the components in the mixture is the basic requirement for this method. NMR methodology involves the direct identification and quantitation of various components from their characteristic {sup 1}H, {sup 13}C and {sup 31}P-NMR chemical shift data. Both IR and NMR techniques have been successfully applied to nine component blends and commercial oils. 5 refs., 4 figs., 4 tabs.

Chopra, A.; Sastry, M.I.S.; Kapur, G.S.; Sarpal, A.S. [Indian Oil Corporation Limited, Faridabad (India)] [and others

1996-04-01

74

a Study of the Radiative Properties of Agglomerated Flame Particulates Using Light Scattering.  

NASA Astrophysics Data System (ADS)

The in-situ optical technique of inferring the soot agglomerate structural and optical properties from the measurements of the extinction cross section, the differential scattering cross section, the dissymmetry ratios in both planes of polarization, and the depolarization ratio, was investigated in detail by this study. A sensitivity analysis of the technique revealed that the dissymmetry ratios are insensitive to both the real and imaginary part of the refractive index. The ratio of the differential scattering to extinction cross sections was also found to be a weak function of the imaginary part of the refractive index. The sensitivity analysis results indicate that the technique is not suitable for inferring accurately the optical properties of the soot agglomerates. Therefore, a known value for the particle refractive index should be used in the agglomerate analysis to infer the morphology of the soot agglomerates. Experimental measurements of the above described quantities from a laminar premixed propane/oxygen flat flame, of fuel equivalence ratio of 2.1, were used with the appropriate agglomerate model to infer the structural agglomerate parameters. Soot samples were also extracted from the flame by using thermophoretic and sampling probes. It was found that the agglomerate model analysis of the measured scattering and extinction quantities (for four different soot refractive index values), underpredicts the degree of agglomeration of the soot particles. A quantitative analysis of the agglomerate morphology of the soot samples extracted with the sampling probe, indicates a self-preserved distribution of the primary particle sizes and the number of primary particles per agglomerate with increasing flame residence time of the agglomerate. A qualitative analysis of the electron microscopy results, of the soot samples extracted with the thermophoretic sampling probe, suggests that the degree of agglomeration is a function of flame residence time, and that the primary particle sizes in the agglomerates are fairly monosized.

Venizelos, Demetris Theodosios

75

Coal Cleaning by Gas Agglomeration  

SciTech Connect

The gas agglomeration method of coal cleaning was demonstrated with laboratory scale mixing equipment which made it possible to generate microscopic gas bubbles in aqueous suspensions of coal particles. A small amount of i-octane was introduced to enhance the hydrophobicity of the coal. Between 1.0 and 2.5 v/w% i-octane was sufficient based on coal weight. Coal agglomerates or aggregates were produced which were bound together by small gas bubbles.

Meiyu Shen; Royce Abbott; T. D. Wheelock

1998-03-01

76

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

77

Hydrodynamics and gas mixing in a carbon nanotube agglomerate fluidized bed  

Microsoft Academic Search

A typical nanoscale fiber material, carbon nanotubes (CNTs), was fluidized in a 280 mm inner diameter (ID) nano-agglomerate fluidized bed (NAFB). The solids distribution and gas mixing were measured by a self-developed conductance method and the hydrogen tracer technique. Typical nano-agglomerate fluidization characteristics, such as high bed expansion ratio and multi-staged agglomerate structure, were observed. Fluidization experiments over a wide

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

2006-01-01

78

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

79

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

Microsoft Academic Search

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

Claudia Parada; Turgay Ertekin

2010-01-01

80

COAL CLEANING BY GAS AGGLOMERATION  

SciTech Connect

The technical feasibility of a gas agglomeration method for cleaning coal was demonstrated by means of bench-scale tests conducted with a mixing system which enabled the treatment of ultra-fine coal particles with a colloidal suspension of microscopic gas bubbles in water. A suitable suspension of microbubbles was prepared by first saturating water with air or carbon dioxide under pressure then reducing the pressure to release the dissolved gas. The formation of microbubbles was facilitated by agitation and a small amount of i-octane. When the suspension of microbubbles and coal particles was mixed, agglomeration was rapid and small spherical agglomerates were produced. Since the agglomerates floated, they were separated from the nonfloating tailings in a settling chamber. By employing this process in numerous agglomeration tests of moderately hydrophobic coals with 26 wt.% ash, it was shown that the ash content would be reduced to 6--7 wt.% while achieving a coal recovery of 75 to 85% on a dry, ash-free basis. This was accomplished by employing a solids concentration of 3 to 5 w/w%, an air saturation pressure of 136 to 205 kPa (5 to 15 psig), and an i-octane concentration of 1.0 v/w% based on the weight of coal.

T.D. Wheelock

1999-03-01

81

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

82

Simple Techniques for Evaluation of Crude Oil Compatibility  

Microsoft Academic Search

Blending crude oils or crude oils and condensates of different origin may give rise to deposit related problems due to incompatibility. Although the problem has been recognized, there are as yet no standard methods for the determination and quantification of crude oil compatibility. This study focused on the compatibility of stock tank oils in storage depots and refineries. Using blends

W. E. M. Schermer; P. M. J. Melein; F. G. A. van den Berg

2004-01-01

83

Development of oil hydrocarbon fingerprinting and identification techniques  

Microsoft Academic Search

Oil, refined product, and pyrogenic hydrocarbons are the most frequently discovered contaminants in the environment. To effectively determine the fate of spilled oil in the environment and to successfully identify source(s) of spilled oil and petroleum products is, therefore, extremely important in many oil-related environmental studies and liability cases. This article briefly reviews the recent development of chemical analysis methodologies

Zhendi Wang; Merv F. Fingas

2003-01-01

84

Coal cleaning by gas agglomeration.  

National Technical Information Service (NTIS)

The technical feasibility of a gas agglomeration method for cleaning coal was demonstrated by means of bench-scale tests conducted with a mixing system which enabled the treatment of ultra-fine coal particles with a colloidal suspension of microscopic gas...

T. D. Wheelock

1999-01-01

85

Adhesion of nanoparticles within spray dried agglomerates  

Microsoft Academic Search

20 m diameter spray-dried agglomerates made up of 210 nm zirconia particles have been individually tested by crushing between rigid plates using a modified nanoindenter. The results show that the agglomerates support considerable stress before deforming. Both the elastic and plastic deformations of the agglomerates have been observed, followed by ultimate failure through a cracking mechanism. A model has been

K. Kendall; T. P. Weihs

1992-01-01

86

Effect of absorption on light scattering by agglomerated debris particles  

Microsoft Academic Search

We study the influence of material absorption on light scattering by agglomerated debris particles whose sizes are comparable with the wavelength. We find that the angular profile of linear polarization is extremely sensitive to the imaginary part of refractive index, and there are some unique features that may assist in the retrieval of physical properties of particles using remote-sensing techniques.

Evgenij Zubko; Hiroshi Kimura; Yuriy Shkuratov; Karri Muinonen; Tetsuo Yamamoto; Hajime Okamoto; Gorden Videen

2009-01-01

87

Application of microbial enhanced oil recovery technique to a Turkish heavy oil  

Microsoft Academic Search

Microbial enhance oil recovery utilizes microorganisms and their metabolic products to improve the recovery of crude oil from reservoir rocks. In this study an anaerobic bacterium, Clostridium acetobutylicum was injected into a one-dimensional model reservoir containing a Turkish heavy oil (Raman oil) at 38° C. This injection was followed by water flooding after a suitable shut-in period. Comparison of oil

Kemal Behlulgil; Tanju Mehmetoglu; Sedat Donmez

1992-01-01

88

Micro-agglomerate flotation for deep cleaning of coal. Quarterly progress report, October 1, 1994--December 31, 1994  

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 mm) needed to achieve adequate liberation of the mineral matter from the coal matrix. It is generally recognized that surface-based separation processes such as froth flotation or selective agglomeration offer considerable potential for such applications but there remain many problems in obtaining the required selectivity with acceptable recovery of combustible matter. In froth flotation, selectivity is substantially reduced at fine sizes due, primarily, to overloading of the froth phase which leads to excessive carryover of water and entrained mineral matter. Oil agglomeration, on the other hand, can provide good selectivity at low levels of oil addition but the agglomerates tend to be too fragile for separation by the screening methods normally used. The addition of larger amounts of oil can yield large, strong agglomerates which are easily separated but the selectivity is reduced and reagent costs can become excessive. We are investigating the use of a hybrid process - micro-agglomerate flotation - which is a combination of oil-agglomeration and froth flotation. 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 extract these micro-agglomerates from the water/dispersed-mineral phase. Since the floating units are agglomerates (about 30-50 mm in size) rather than individual coal particles (1-10 mm) the problems of froth overload and water/mineral carryover should be significantly alleviated. Micro-agglomerate flotation has considerable potential for the practical deep cleaning of coal on a commercial scale.

Chander, S.; Hogg, R.

1995-01-01

89

Phenolic compounds of virgin olive oil: influence of paste preparation techniques  

Microsoft Academic Search

An experimental investigation was carried out on olive oils of the Ogliarola Salentina and Coratina cultivars to assess the influence of the two different olive grinding techniques and kneading process on the quality of the oils. The experimental data obtained showed that resistance to oxidation, total phenols and phenolic compounds analysed for HPLC were higher in the Coratina oils than

Francesco Caponio; Vincenzo Alloggio; Tommaso Gomes

1999-01-01

90

Preparation and characterization of agglomerated porous hollow silica supports for olefin polymerization catalyst  

Microsoft Academic Search

Self-prepared porous hollow silica (PHS) nanoparticles were agglomerated with an oil (kerosene)–ammonia method and used as a novel support of metallocene catalysts for olefin polymerization. Transmission electron microscopy (TEM), scanning electron microcopy (SEM), small-angle X-ray diffraction (SA-XRD) and nitrogen adsorption–desorption were employed to characterize the morphologies and mesostructures of the PHS particles and agglomerated PHS particles. It was found that

Jian-Feng Chen; Ji-Rui Song; Li-Xiong Wen; Hai-Kui Zou; Lei Shao

2007-01-01

91

Evaluation of alternative oil spill cleanup techniques in a Spartina alterniflora salt marsh.  

PubMed

Three oil spill situations which cause long-term impact were simulated in 1 m(2) salt marsh plots to evaluate the effectiveness of alternative cleanup techniques at removing oil and reducing damage to Spartina alterniflora. Cleanup techniques, implemented 18-24 h after oiling, were not effective at removing oil after sediment penetration. When oil remained on the sediment surface, flushing techniques were most effective at removal, reducing levels of added oil by 73% to 83%. The addition of dispersant to the flushing stream only slightly enhanced oil removal. Clipping of vegetation followed by sorbent pad application to sediment was moderately effective, reducing added oil by 36% to 44%. In contrast to flushing and clipping, burning increased the amount of oil in sediment by 27% to 72%. Although flushing and clipping were effective at oil removal, neither technique reduced initial damage to plants or enhanced long-term recovery. While flushed plots sustained no additional plant damage due to cleanup, clipped and burned plots sustained additional initial plant damage. Based on these results, first considerations should be given to natural tidal flushing as the means to remove oil, especially in salt marshes subject to ample tidal inundation. Although our results do not support cleanup in salt marshes with ample tidal inundation, low pressure flushing may be warranted when fuel oils or large quantities of crude oil impact salt marshes subject to reduced tidal flushing. Flushing, when warranted, should be initiated prior to oil penetration into the substrate. Clipping may be considered as a cleanup response only when heavy oil cannot be effectively removed from vegetation by flushing. Burning is not recommended because it enhances oil penetration into sediment and causes substantial initial plant damage. PMID:15092503

Kiesling, R W; Alexander, S K; Webb, J W

1988-01-01

92

Coal Beneficiation by Gas Agglomeration  

DOEpatents

Coal beneficiation is achieved by suspending coal fines in a colloidal suspension of microscopic gas bubbles in water under atmospheric conditions to form small agglomerates of the fines adhered by the gas bubbles. The agglomerates are separated, recovered and resuspended in water. Thereafter, the pressure on the suspension is increased above atmospheric to deagglomerate, since the gas bubbles are then re-dissolved in the water. During the deagglomeration step, the mineral matter is dispersed, and when the pressure is released, the coal portion of the deagglomerated gas-saturated water mixture reagglomerates, with the small bubbles now coming out of the solution. The reagglomerate can then be separated to provide purified coal fines without the mineral matter.

Thomas D. Wheelock; Meiyu Shen

2000-03-15

93

Development of Extraction Techniques for the Detection of Signature Lipids from Oil  

SciTech Connect

Pure cultures, including Desulfovibrio vulgaris and Methanococcus maripaludus, were combined with model oil samples and oil/diesel mixtures to optimize extraction techniques of signature lipids from oil in support of investigation of microbial communities in oil deposit samples targets for microbial enhanced hydrocarbon recovery. Several techniques were evaluated, including standard phospholipid extraction, ether linked lipid for Archaeal bacterial detection, and high pressure extractiontechniques. Recovery of lipids ranged from 50-80percent as compared to extraction of the pure culture. Extraction efficiency was evaluated by the use of internal standards. Field samples will also be tested for recovery of signature lipids with optimized extraction techniques.

Borglin, Sharon; Geller, Jil; Chakraborty, Romy; Hazen, Terry; Mason, Olivia

2010-05-17

94

An analysis of oil and gas supply modeling techniques and a survey of offshore supply models  

SciTech Connect

This report surveys the literature on empirical oil and gas supply modeling techniques. These techniques are categorized as either geologic/engineering, econometric, or hybrid - the last being a combination of geologic and econometric techniques. The geologic/ engineering models are further disaggregated into play analysis models and discovery process models. The strengths and weaknesses of each of the models are discussed. The report concludes with a discussion of how these techniques have been applied to offshore oil and gas supply.

Walls, M.A.

1990-01-01

95

Lubricant properties of Moringa oil using thermal and tribological techniques  

Microsoft Academic Search

The increasing application of biobased lubricants could significantly reduce environmental pollution and contribute to the\\u000a replacement of petroleum base oils. Vegetable oils are recognized as rapidly biodegradable and are thus promising candidates\\u000a for use as base fluids in formulation of environment friendly lubricants. Although many vegetable oils have excellent lubricity,\\u000a they often have poor oxidation and low temperature stability. Here

Brajendra K. Sharma; Umer Rashid; Farooq Anwar; Sevim Z. Erhan

2009-01-01

96

Application of microbial enhanced oil recovery technique to Daqing Oilfield  

Microsoft Academic Search

Pseudomonas aeruginosa (P-1) and its metabolic products (PIMP) of 10% could enhance the oil recovery in the model reservoir by 11.2% and also decrease injection pressure by 40.1%. Further, PIMP (10%) could reduce the crude oil viscosity by 38.5%. In the pilot tests, about 80% of wells used showed a significant increase in crude oil production after PIMP injection and

Qingxin Li; Congbao Kang; Hao Wang; Chunde Liu; Changkai Zhang

2002-01-01

97

A general procedure to functionalize agglomerating nanoparticles demonstrated on nanodiamond.  

PubMed

Upon reduction of particle size to the nanometer range, one has to deal with the general issue of spontaneous agglomeration, which often obstructs postsynthesis modification of nanoparticle surfaces. A technique to cope with this phenomenon is required to realize a wide variety of applications using nanoparticles in solvents or as refined assemblies. In this article, we report on a new technique to facilitate surface chemistry of nanoparticles in a conventional glassware system. A beads-assisted sonication (BASD) process was examined to break up persistent agglomerates of nanodiamonds in two different reactions for simultaneous surface functionalization. The chosen reactions are the silanization with an acrylate-modified silane and the arylation using diazonium salts. The BASD process can be successfully applied even where the original material is not dispersible in the reaction solvent at all, as the formation of ever smaller, increasingly functionalized agglomerates is improving their solubility. We have confirmed that the presence of ceramic beads enables functionalization of each primary particle, while conventional magnetic stirring or beadless sonication can reach primary particles only when agglomeration is loose. Additionally, mechanical surface modification of nanodiamond was found to take place by BASD with high energy density, leading to sp(2)-hybridized surface patches on nanodiamond. This allowed for the efficient grafting of aryl groups to the surface of primary diamond nanoparticles. Stable, homogeneously functionalized nanodiamond particles in colloidal solution can be obtained by this method. PMID:19601635

Liang, Yuejiang; Ozawa, Masaki; Krueger, Anke

2009-08-25

98

Thermal diffusivity measurements in vegetable oils with thermal lens technique  

Microsoft Academic Search

Using a thermal lensing experimental setup the thermal properties of several vegetable oils were obtained. The samples were oils from Amazonian species and olive (the popular identifications are piqui, copaiba, buriti, and babaçu). The two lasers mismatched mode experimental configuration was used, with a He-Ne laser as the probe and an Ar+ laser as the excitation one. The time resolved

J. Bernal-Alvarado; A. M. Mansanares; E. C. da Silva; S. G. C. Moreira

2003-01-01

99

A new technique for oil backstreaming contamination measurements  

NASA Astrophysics Data System (ADS)

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 was measured in the Space Power Facility (SPF) near Sandusky, OH, the largest space simulation vacuum test chamber in the U.S.. Small clean silicon wafers placed at all desired measurement sites were used as contamination sensors. 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 the silicon substrate uniformly, two analysis models were developed to measure the oil film: (1) continuous, homogeneous film; and (2) 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 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 examples exposed to the same vacuum runs.

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

100

Thermal diffusivity measurements in vegetable oils with thermal lens technique  

NASA Astrophysics Data System (ADS)

Using a thermal lensing experimental setup the thermal properties of several vegetable oils were obtained. The samples were oils from Amazonian species and olive (the popular identifications are piqui, copaiba, buriti, and babaçu). The two lasers mismatched mode experimental configuration was used, with a He-Ne laser as the probe and an Ar+ laser as the excitation one. The time resolved spectra were measured using an automatic system, and fitting the aberrant theoretical model to the data, the characteristic relaxation time were obtained, and knowing this value, the thermal property of each oil was solved.

Bernal-Alvarado, J.; Mansanares, A. M.; da Silva, E. C.; Moreira, S. G. C.

2003-01-01

101

Micro-agglomerate flotation for deep cleaning of coal. Quarterly technical progress report, April 1, 1995--June 30, 1995  

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 mm) needed to achieve adequate liberation of the mineral matter from the coal matrix. In froth flotation, selectivity is substantially reduced at fine sizes due, primarily, to overloading of the froth phase which leads to excessive carryover of water and entrained mineral matter. Oil agglomeration, on the other hand, can provide good selectivity at low levels of oil addition but the agglomerates tend to be too fragile for separation by the screening methods normally used. This project is concerned with a hydrid process, micro-agglomerate flotation, which is a combination of oil agglomeration and froth flotation.

Chander, S.; Hogg, R.

1995-07-01

102

Comparison of three atomic absorption techniques for determining metals in soybean oil  

Microsoft Academic Search

Three different atomic absorption techniques were used to analyze metals contained in three different crude soybean oils.\\u000a In the first, oil was decomposed by charring followed by high-temperature dry ashing. The ash then was dissolved in a dilute\\u000a acidic aqueous medium. In the second, oil diluted with methyl isobutyl ketone as the solvent was aspirated directly. In the\\u000a third, the

L. T. Black

1975-01-01

103

A new technique for collecting ambient diesel particles for bioassays.  

PubMed

This paper describes a new application of a viable aerosol sampler, the Liquid Electrostatic Aerosol Precipitator (LEAP), for the collection of diesel particles for bioassays of pulmonary toxicity and mutagenicity or carcinogenicity. Currently used methods (filtration, dry electrostatic precipitation) cause agglomeration of particles and increases in particle size up to twenty-fold, which may alter particle toxicity significantly. Collection of diesel particles with the LEAP preserved submicronic particle size. Differences in chemical composition of extracts of surface adsorbents as compared to particles collected on filters also were observed. This technique may be applicable for collection of other types of combustion products or oil mists that agglomerate when collected by filtration. PMID:2438921

Hallock, M F; Smith, T J; Hammond, S K; Beck, B D; Brain, J D

1987-05-01

104

The Removal of Heavy Metal Ions from Waste Water Using Jojoba Oil in a New Technique  

Microsoft Academic Search

The removal of heavy metal ions (Cu and Pb) from their aqueous solutions of cupper sulfate and lead nitrate has been investigated with a new technique using jojoba oil obtained from solvent extraction of prepressed jojoba meal. Synthetic aqueous solutions having different initial concentrations (20–80 ppm) were treated with different jojoba oil doses ranging from 2–15% by mixing for different

O. S. El Kinawy; N. A. El Moneim; D. E. El Haron

2012-01-01

105

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

106

Application of modern diagnostic techniques to assess the condition of oil and pressboard  

Microsoft Academic Search

Aging of oil-paper insulation was investigated under controlled laboratory conditions. Traditional and modern diagnostic tools and techniques are discussed. Insulation condition testing includes common chemical diagnostics such as acidity tests and several new chemical techniques such as determination of relative content of dissolved decay products by spectrophotometry, solid suspension by turbidimetry, Fourier transform infrared spectroscopy, and electrical diagnostic techniques that

A. Bouaicha; I. Fofana; M. Farzaneh

2008-01-01

107

Agglomeration in fluidized beds: detection and counteraction  

Microsoft Academic Search

Fluidized beds comprise a quantity of solid particles that is suspended by an upward flowing gas. They are used for a variety of processes in the chemical industry, such as catalytic reactions, drying, coating and energy conversion. A major problem in industrial practice is the occurrence of unwanted agglomeration, i.e. solid particles adhering to each other and forming larger agglomerates.

Bartels. M

2008-01-01

108

Agglomeration and size enlargement session summary paper  

Microsoft Academic Search

This paper provides a summary of the Agglomeration and Size Enlargement session of the First International Particle Technology Forum held in Denver, CO, USA, August 17–19, 1994. The conference was sponsored by the recently formed Particle Technology Forum of the American Institute of Chemical Engineers. This first session on agglomeration and size enlargement brought together a cross-section of industries dealing

Bryan J. Ennis

1996-01-01

109

Toward a Domain-Specific Modeling Technique for Oil-Drilling Engineering Applications  

Microsoft Academic Search

Applications for oil-drilling engineering simulation are characterized with heterogeneous data and resources, complicated business processes and changing business requirements from users. It is of practical significance and great value to find out a business modeling technique for the class of oil-drilling engineering applications. In this paper, we proposed a goal-tree modeling technique for domain-specific software. This domain-specific model consists of

Feng Jiao; Liping Wang; Chuan Zhi Liu

2008-01-01

110

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

111

Micro-agglomerate flotation for deep cleaning of coal. Quarterly progress report, September 30--December 31, 1992  

SciTech Connect

We are investigating the use of a hybrid process - Micro-agglomerate flotation - which is a combination of oil-agglomeration and froth flotation. 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 extract these micro-agglomerates from the water/dispersed-mineral phase. Since the floating units are agglomerates (about 30--50 {mu}m in size) rather than individual coal particles (1--10 {mu}m) the problems of froth overload and water/mineral carryover should be significantly alleviated. Micro-agglomerate flotation has considerable potential for the practical deep cleaning of coal on a commercial scale. In principle, it should be possible to achieve both high selectivity and high yield at reasonable cost. The process requires only conventional, off-the-shelf equipment and reagent usage (oil, surfactants, etc.) should be small. 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 necessary to maintain precise control over the chemistry of the liquid phases in order to promote the interfacial reactions and interactions between phases necessary to ensure selectivity. Kinetics as well as thermodynamic factors may be critical in determining overall system response.

Chander, S.; Hogg, R.

1993-01-01

112

Micro-agglomerate flotation for deep cleaning of coal. Quarterly progress report, January 1--March 31, 1994  

SciTech Connect

We are investigating the use of a hybrid process -- Micro-agglomerate flotation which is a combination of oil-agglomeration and froth flotation. 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 extract these micro-agglomerates from the water/dispersed-mineral phase. Since the floating units are agglomerates (about 30--50 {mu}m in size) rather than individual coal particles (1--10 {mu}m) the problems of froth overload and water/mineral carryover should be significantly alleviated. Micro-agglomerate flotation has considerable potential for the practical deep cleaning of coal on a commercial scale. In principle, it should be possible to achieve both high selectivity and high yield at reasonable cost. The process requires only conventional, off-the-shelf equipment and reagent usage (oil, surfactants, etc.) should be small. 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 necessary to maintain precise control over the chemistry of the liquid phases in order to promote the interfacial reactions and interactions between phases necessary to ensure selectivity. Kinetics as well as thermodynamic factors may be critical in determining overall system response.

Chander, S.; Hogg, R.

1994-04-01

113

Oil spill cleanup and protection techniques for shorelines and marshlands  

Microsoft Academic Search

A major oil spill ends in contamination of coastal or inland shorelines and marshlands, with possible environmental and economic damage. Such damage can be significantly reduced if proper protection and cleanup actions are taken promptly. The book provides a systematic methodology that can be used to assess the threat or extent of contamination and to choose the most appropriate protection\\/cleanup

Breuel

1981-01-01

114

Robust satellite techniques for oil spill detection and monitoring  

Microsoft Academic Search

Discharge of oil into the sea is one of the most dangerous, among technological hazards, for the maritime environment. In the last years maritime transport and exploitation of marine resources continued to increase; as a result, tanker accidents are nowadays increasingly frequent, continuously menacing the maritime security and safety. Satellite remote sensing could contribute in multiple ways, in particular for

D. Casciello; N. Pergola; V. Tramutoli

2004-01-01

115

A new technique for oil backstreaming contamination measurements  

Microsoft Academic Search

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 was measured in the Space Power Facility (SPF) near Sandusky, OH, the largest

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

1991-01-01

116

Industrial agglomeration and the regional scientific explanation of perceived environmental injustice  

Microsoft Academic Search

This article evaluates the impact on an environmental justice analysis of explicitly controlling for forces of agglomeration.\\u000a Many environmental justice studies have examined whether polluting facilities are disproportionately concentrated near certain\\u000a types of people, such as minorities. No studies so far have explicitly included a proxy for agglomeration, and relatively\\u000a few use appropriate spatial analytic techniques. Our analysis does both,

William M. Bowen; Mark Atlas; Sugie Lee

2009-01-01

117

Vacuum metal deposition: visualisation of gold agglomerates using TEM imaging.  

PubMed

Vacuum metal deposition (VMD) is a well-established technique that can be used for the development of latent fingermarks on a range of polymer surfaces, including polyethylene (PE) bags exposed to harsh environmental conditions. The technique has also proved to be effective on difficult semi-porous surfaces such as the polymer banknotes in circulation in Australia and in an increasing number of other countries. VMD is a two-stage technique. In the first stage, a small amount of gold is deposited under high vacuum onto the exhibit. This is then followed by the deposition, onto the gold layer, of a much thicker layer of zinc. Normal VMD development is characterised by zinc depositing all over the surface except on the fingermark ridges themselves. A phenomenon of reverse development (zinc on the ridges but not on the surface) has been reported by many authors. Recent studies indicated that this phenomenon might occur on low-density polyethylene (LDPE) when the amount of deposited gold is above an optimum quantity. The results suggested that the size of the gold agglomerates formed on the surface of the polymer plays a critical role. This preliminary study was aimed at visualising, by transmission electron microscopy (TEM), the formation of gold agglomerates on polymer surfaces to gain an appreciation of how the density and size of these agglomerates changes with an increasing amount of evaporated gold. PMID:16513309

Dai, Xuejing; Stoilovic, Milutin; Lennard, Chris; Speers, Naomi

2006-02-28

118

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

119

Economic analysis of secondary and enhanced oil recovery techniques in Wyoming  

NASA Astrophysics Data System (ADS)

This dissertation primarily aims to theoretically analyze a firm's optimization of enhanced oil recovery (EOR) and carbon dioxide sequestration under different social policies and empirically analyze the firm's optimization of enhanced oil recovery. The final part of the dissertation empirically analyzes how geological factors and water injection management influence oil recovery. The first chapter builds a theoretical model to analyze economic optimization of EOR and geological carbon sequestration under different social policies. Specifically, it analyzes how social policies on sequestration influence the extent of oil operations, optimal oil production and CO2 sequestration. The theoretical results show that the socially optimal policy is a subsidy on the net CO2 sequestration, assuming negative net emissions from EOR. Such a policy is expected to increase a firm's total carbon dioxide sequestration. The second chapter statistically estimates the theoretical oil production model and its different versions. Empirical results are not robust over different estimation techniques and not in line with the theoretical production model. The last part of the second chapter utilizes a simplified version of theoretical model and concludes that EOR via CO2 injection improves oil recovery. The final chapter analyzes how a contemporary oil recovery technology (water flooding of oil reservoirs) and various reservoir-specific geological factors influence oil recovery in Wyoming. The results show that there is a positive concave relationship between cumulative water injection and cumulative oil recovery and also show that certain geological factors affect the oil recovery. Moreover, the curvature of the concave functional relationship between cumulative water injection and oil recovery is reservoir-specific due to heterogeneities among different reservoirs.

Kara, Erdal

120

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

121

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

Microsoft Academic Search

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

RONALD E. SMITH; W. JERRY PARKINSON; NEAL J. MILLER

2002-01-01

122

Robust Satellite Techniques for oil spill detection and monitoring using AVHRR thermal infrared bands  

Microsoft Academic Search

In this article, a new satellite technique for oil spill detection and monitoring is fully presented and discussed. It is based on the general RST (Robust Satellite Techniques) approach applied to Advanced Very High Resolution Radiometer (AVHRR) observations in the thermal infrared region of the electromagnetic spectrum. The proposed approach, which exploits the analysis of multi-temporal satellite records, seems to

D. Casciello; T. Lacava; N. Pergola; V. Tramutoli

2011-01-01

123

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

124

Self-preserving size distributions of agglomerates  

Microsoft Academic Search

The attainment of self-preserving distributions by coagulation of agglomerate or aggregate particles has been investigated in the continuum and free-molecular regimes. Self-preserving distributions have been computed for agglomerates of various fractal dimensions. In the free-molecular regime, the self-preserving size distributions broaden as the fractal dimension decreases. In contrast, in the continuum regime, the distributions narrow with decreasing fractal dimension.The aggregate

Srinivas Vemury; Sotiris E. Pratsinis

1995-01-01

125

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

126

New study updates economics of five EOR techniques. [Enhanced oil recovery  

SciTech Connect

During the last several years, costs and revenues associated with enhanced oil recovery have changed significantly. The market price for tertiary oil has more than doubled, but inflation also has increase investment and operating costs. In addition, there have been changes in taxation, such as the addition of the Windfall Profit Tax. These events have changed the economics of enhanced oil recovery. To evaluate these changes, a project was conducted to collect and update cost data to mid-1980, update the recovery models for each EOR technique, and evaluate the economics of each EOR method. The final report analyzes the economics of 5 different EOR techniques in mid-1980 dollars on a consistent basis, incorporating experimental results, field tests, and an improved understanding of EOR processes that have been obtained since 1978. Costs were derived by geographical region for the following techniques: steam drive, in-situ combustion, carbon dioxide flooding, surfactant/polymer flooding, and polymer waterflooding.

Not Available

1981-05-18

127

Development of Improved Oil Field Waste Injection Disposal Techniques  

SciTech Connect

The goals of this DOE sponsored project are to: (1) assemble and analyze a comprehensive database of past waste injection operations; (2) develop improved diagnostic techniques for monitoring fracture growth and formation changes; (3) develop operating guidelines to optimize daily operations and ultimate storage capacity of the target formation; and (4) to test these improved models and guidelines in the field.

Terralog Technologies USA Inc.

2001-12-17

128

Development of Improved Oil Field Waste Injection Disposal Techniques  

SciTech Connect

The goals of this project have was to: (1) assemble and analyze a comprehensive database of past waste injection operations; (2) develop improved diagnostic techniques for monitoring fracture growth and formation changes; (3) develop operating guidelines to optimize daily operations and ultimate storage capacity of the target formation; and (4) to apply these improved models and guidelines in the field.

Terralog Technologies

2002-11-25

129

Upgrading of coal liquefaction feedstock by selective agglomeration  

SciTech Connect

The technical feasibility study of using selective agglomeration (with coal-derived oil) to upgrade Illinois No. 6 coal for a liquefaction feedstock was completed. Effects of coal particle size, slurry pH, oil-to-coal ratio, and operating temperature on mineral matter reduction, clean coal weight recovery, and clean coal moisture content were studied. The addition of coal-derived naphtha or kerosene as conditioners to increase hydrophobicity and recovery of coal was also investigated. Results showed that approximately 70% of the mineral matter could be removed from this coal at a clean coal weight recovery of over 85% by grinding the coal to a mean volume diameter of about 10 microns and properly selecting of the operation variables.

Lai, R.; Sinha, K.; Richardson, A.; Killmeyer, R.; Utz, B.; Hickey, R.; Cillo, D.

1994-03-01

130

Generating nano-aerosols from TiO? (5 nm) nanoparticles showing different agglomeration states. Application to toxicological studies.  

PubMed

Agglomeration of nanoparticles (NP) is a key factor in the generation of aerosols from nano-powders and may represent an important parameter to consider in toxicological studies. For this reason, the characterization of NP aerosols (e.g., concentration, size, and structure of agglomerates) is a critical step in the determination of the relationship between exposure and effects. The aim of this study was to generate and characterize aerosols composed of TiO? (5 nm) NP showing different agglomeration states. Two concentrations were tested: 2 and 7 mg/m³. Stable mass concentrations over 6 hr were successfully generated by a wet method using Collison and Delavan nebulizers that resulted in aerosols composed of smaller agglomerates (<100 nm), while aerosols composed of larger agglomerates (>100 nm) were obtained by dry generation techniques using either a Palas dust feeder or a Fluidized Bed. Particle size distributions in the aerosols were determined by an electrical low pressure impactor. Median number aerodynamic diameters corresponding to the aerosol with smaller and larger agglomerates were 30 and 185 nm, respectively, for the 2 mg/m³ concentration, and 31 and 194 nm for the 7 mg/m³ experiment. Image analysis by transmission electron microscopy showed the presence of compact or agglomerates with void spaces in the different nano-aerosols. These characterized nano-aerosols will be used in further experiments to study the influence of agglomerate size on NP toxicity. PMID:23252512

Noël, Alexandra; Cloutier, Yves; Wilkinson, Kevin James; Dion, Chantal; Hallé, Stéphane; Maghni, Karim; Tardif, Robert; Truchon, Ginette

2013-01-01

131

Centrifugal air-assisted melt agglomeration for fast-release "granulet" design.  

PubMed

Conventional melt pelletization and granulation processes produce round and dense, and irregularly shaped but porous agglomerates respectively. This study aimed to design centrifugal air-assisted melt agglomeration technology for manufacture of spherical and yet porous "granulets" for ease of downstream manufacturing and enhancing drug release. A bladeless agglomerator, which utilized shear-free air stream to mass the powder mixture of lactose filler, polyethylene glycol binder and poorly water-soluble tolbutamide drug into "granulets", was developed. The inclination angle and number of vane, air-impermeable surface area of air guide, processing temperature, binder content and molecular weight were investigated with reference to "granulet" size, shape, texture and drug release properties. Unlike fluid-bed melt agglomeration with vertical processing air flow, the air stream in the present technology moved centrifugally to roll the processing mass into spherical but porous "granulets" with a drug release propensity higher than physical powder mixture, unprocessed drug and dense pellets prepared using high shear mixer. The fast-release attribute of "granulets" was ascribed to porous matrix formed with a high level of polyethylene glycol as solubilizer. The agglomeration and drug release outcomes of centrifugal air-assisted technology are unmet by the existing high shear and fluid-bed melt agglomeration techniques. PMID:22531845

Wong, Tin Wui; Musa, Nafisah

2012-04-17

132

Agglomerate formation and growth mechanisms during melt agglomeration in a rotary processor.  

PubMed

The purpose of this study was to investigate the effect of the binder particle size and the binder addition method on the mechanisms of agglomerate formation and growth during melt agglomeration in a laboratory scale rotary processor. Lactose monohydrate was agglomerated with molten polyethylene glycol (PEG) 3000 by adding the PEG either as solid particles from the size fraction 0-250, 250-500, or 500-750 microm or as droplets with a median size of 25, 48, or 69 microm. It was found that the PEG particle size, the PEG droplet size, and the massing time significantly influenced the agglomerate size and size distribution. Agglomerate formation and growth were found to occur primarily by distribution and coalescence for the PEG size fraction 0-250 microm and mainly by the immersion mechanism for the PEG size fractions 250-500 and 500-750 microm. When the PEG was sprayed upon the lactose, the mechanism of agglomerate formation was supposed to be a mixture of immersion and distribution, and the agglomerate growth was found to occur by coalescence regardless of the PEG mean droplet size. Compared to high shear mixers and conventional fluid bed granulators, the mechanisms of agglomerate formation and growth in the rotary processor resembled mostly those seen in the fluid bed granulator. PMID:16198077

Vilhelmsen, Thomas; Schaefer, Torben

2005-09-27

133

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

2011-11-23

134

Investigation of self-help oil-spill response techniques and equipment  

SciTech Connect

The US Coast Guard commissioned Pacific Northwest Laboratory (PNL) to conduct this study of 45 self-help oil-spill response techniques and equipment for oceangoing tankers and inland tank barges to assess the potential effectiveness of the proposed countermeasure categories. This study considers the hypothetical outflow of oil in the case of side damage and bottom damage to single-hull designs. The results will be considered by the Coast Guard in drafting regulations pertaining to the requirement for tanker vessels to carry oil pollution response equipment (i.e., in response to the oil Pollution Act of 1990). PNL's approach to this investigation included: assessing time-dependent oil outflow in the cases of collision and grounding of both tankers and barges; identifying environmental constraints on self-help countermeasure operation; identifying human factor issues, such as crew performance, safety, and training requirements for the self-help countermeasures considered; and assessing each self-help countermeasure with respect to its potential for minimizing oil loss to the environment. Results from the time-dependent oil outflow, environmental limitations, and human factors requirements were input into a simulation model.

Enderlin, W I; Downing, J P; Enderlin, C W; Sanquist, T F; Pope, W S

1992-06-01

135

Enhancement of anti-cholinesterase activity of Zingiber cassumunar essential oil using a microemulsion technique.  

PubMed

The aim of the present study was to enhance the cholinesterase inhibitory activity of Zingiber cassumunar (ZC) oil using a microemulsion (ME) technique. Pseudoternary phase diagrams of the oil, water, and surfactant/co-surfactant mixture were constructed using a water titration method. Effects of co-surfactant, surfactant/co-surfactant ratio, ionic strength, and pH were examined by means of the microemulsion region which existed in the phase diagrams. The inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were tested by Ellman's colorimetric assay. It was found that ZC oil possesses inhibitory activity against not only AChE but also BChE. Formulation of ZC oil as ME revealed that alkyl chain length and number of hydroxyl groups of co-surfactant exhibited a remarkable effect on the pseudoternary phase diagram. Longer alkyl chains and more hydroxyl groups gave smaller regions of MEs. Ionic strength also affected the ME region. However, the phase behavior was hardly influenced by pH. The suitable ZC oil ME was composed of Triton X-114 in combination with propylene glycol. The anti-cholinesterase activity of this ME was much higher than that of native ZC oil. It exhibited twenty times and twenty five times higher inhibitory activity against AChE and BChE, respectively. ZC oil loaded ME is an attractive formulation for further characterization and an in vivo study in an animal model with Alzheimer's disease. PMID:23229145

Okonogi, S; Chaiyana, W

2012-10-01

136

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

NASA Astrophysics Data System (ADS)

The thermal wave resonator cavity (TWRC) was used to measure the thermal properties of vegetable oils. The thermal diffusivity of six commercial vegetable oils (olive, corn, soybean, canola, peanut, and sunflower) was measured by means of this device. A linear relation between both the amplitude and phase as functions of the cavity length for the TWRC was observed and used for the measurements. Three significant figure precisions were obtained. A clear distinction between extra virgin olive oil and other oils in terms of thermal diffusivity was shown. The high measurement precision of the TWRC highlights the potential of this relatively new technique for assessing the quality of this kind of fluids in terms of their thermophysical properties.

Balderas-López, J. A.; Mandelis, Andreas

2003-01-01

137

Augmenting a Microbial Selective Plugging Technique with Polymer Flooding to Increase the Efficiency of Oil Recovery - A Search for Synergy  

Microsoft Academic Search

The overall objective of this project was to improve the effectiveness of a microbial selective plugging technique of improving oil recovery through the use of polymer floods. More specifically, the intent was to increase the total amount of oil recovered and to reduce the cost per barrel of incremental oil.

Lewis R. Brown; Charles Pittman Jr; F. Leo Lynch

2003-01-01

138

Augmenting a Microbial Selective Plugging Technique with Polymer Flooding to Increase the Efficiency of Oil Recovery - A Search for Synergy  

SciTech Connect

The overall objective of this project was to improve the effectiveness of a microbial selective plugging technique of improving oil recovery through the use of polymer floods. More specifically, the intent was to increase the total amount of oil recovered and to reduce the cost per barrel of incremental oil.

Brown, Lewis R.; Pittman Jr., Charles U.; Lynch, F. Leo; Vadie, A. Alex

2003-02-10

139

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

140

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

1992-06-01

141

Knowledge management techniques for know-how transfer systems design : the case of an oil company  

Microsoft Academic Search

This paper presents a research in progress on the use of knowledge engineering and knowledge management techniques for the development of a strategic approach for the transfer of professional know-how. This transfer is based on the design of devices for sharing and learning clearly identified knowledge in the oil industry domains. This work is based on a pilot study which

Djilali Benmahamed; Jean-Louis Ermine

2007-01-01

142

Oil spill classification from multi-spectral satellite images: exploring different machine learning techniques  

NASA Astrophysics Data System (ADS)

This work describes the potential of oil spill classification from optical satellite images, as investigated by applying different machine learning techniques to a dataset of more than 300 oil spill candidates, which have been detected from multi-spectral satellite sensors during the years 2008 and 2009, over the entire area of the Mediterranean Sea. A set of geometrical and grey level features from Synthetic Aperture Radar (SAR) literature has been extracted from the regions of interest in order to characterize possible oil spills and feed the classification system. Results obtained by applying different machine learning classifiers to the dataset, and the achieved performance are discussed. In particular, as a first approach to oil spill classification, simple statistical classifiers and neural networks were used. Then, a more interpretable fuzzy rule-based classifier was employed, and performance evaluation was refined by exploiting Receiver Operating Characteristic (ROC) analysis. Finally, since oil spill dataset collection happens incrementally, a suitable technique for online classification was proposed, encompassing at the same time cost-oriented classification, in order to allow for a dynamic change of the misclassification costs. This latter goal has been achieved by building an ensemble of cost-oriented, incremental and decremental support vector machines, exploiting the concept of the ROC convex hull.

Corucci, Linda; Nardelli, Fabio; Cococcioni, Marco

2010-10-01

143

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

144

Oil-field wastewater purification by magnetic separation technique using a novel magnetic nanoparticle  

NASA Astrophysics Data System (ADS)

In the present work, oil-field wastewater purification through superconducting magnetic separation technique using a novel magnetic nanoparticle was investigated. The magnetic nanoparticle, which has a multi-shell structure with ferroferric oxide as core, dense nonporous silica as inter layer and mesoporous silica as outer layer, was synthesized by co-precipitation method. To functionalize the magnetic nanoparticle, plasma polymerization technique was adopted and poly methyl acrylate (PMA) was formed on the surface of the nanoparticle. The multi-shell structure of the nanoparticle was confirmed by transmission electron microscope (TEM) and the characteristic is measurable by FTIR. It is found that most of the pollutants (85% by turbidity or 84% by COD value) in the oil-field wastewater are removed through the superconducting magnetic separation technique using this novel magnetic nanoparticle.

Liu, Zhuonan; Yang, Huihui; Zhang, Hao; Huang, Chuanjun; Li, Laifeng

2012-12-01

145

A comparison between different techniques for the isolation of rosemary essential oil.  

PubMed

Traditional hydrodistillation (HD), supercritical fluid extraction (SFE), organic solvent extraction (SE), and water microwave assisted hydrodistillation (MAHD) techniques were compared and evaluated for their effectiveness in the isolation of rosemary essential oil. The microwave assisted hydrodistillation technique was optimized in terms of both delivered power and time duration. The extracts/distillates were analyzed by GC and GC-MS. Microwave distillation, which exploits the physical action of microwaves on plants, showed a series of advantages over the other approaches: low cost, use of water in sample pre-treatment step, greatly reduced isolation time, and attainment of high quality essential oil distillate. Moreover, the absence of environmental impact of this innovative technique was also emphasized. PMID:15776930

Presti, Maria Lo; Ragusa, Salvatore; Trozzi, Alessandra; Dugo, Paola; Visinoni, Franco; Fazio, Alessia; Dugo, Giovanni; Mondello, Luigi

2005-02-01

146

Search for Free Fractional Electric Charge Elementary Particles Using an Automated Millikan Oil Drop Technique  

SciTech Connect

We have carried out a direct search in bulk matter for free fractional electric charge elementary particles using the largest mass single sample ever studied--about 17.4 mg of silicone oil. The search used an improved and highly automated Millikan oil drop technique. No evidence for fractional charge particles was found. The concentration of particles with fractional charge more than 0.16e (e being the magnitude of the electron charge) from the nearest integer charge is less than 4.71x10{sup -22} particles per nucleon with 95% confidence. (c) 2000 The American Physical Society.

Halyo, V.; Kim, P.; Lee, E. R.; Lee, I. T.; Loomba, D.; Perl, M. L.

2000-03-20

147

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

148

Attracting foreign manufacturing: Investment promotion and agglomeration  

Microsoft Academic Search

We study Japanese investments between 1980 and 1992 to assess the effectiveness of US state promotion efforts in light of strong agglomeration effects in Japanese investment. The provision of foreign trade zones, lower taxes, and job-creation subsidies have statistically significant effects on the location of investment. Simulations indicate that unilateral withdrawal of promotion would have caused individual states to lose

C. Keith Head; John C. Ries; Deborah L. Swenson

1999-01-01

149

Pulse combusted acoustic agglomeration apparatus and process  

Microsoft Academic Search

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

Mansour; Momtaz N

1993-01-01

150

Alternate spectrometric oil-analysis techniques. Final report, May 88-Sep 90  

SciTech Connect

Oil analysis results from currently used AE (atomic emission) and AA (atomic absorption) techniques are compared with those from various other techniques such as ICP (inductively coupled plasma), DCP (direct current plasma), graphite furnace AA, ferrography and particle size distribution using the acid dissolution method (ADM). The effect of fine filtration on the analysis capability of the various methods was investigated using a test rig equipped with a 3-micron operational in-depth type oil filter. This investigation also includes studies related to ICP sample introduction systems, overloading of ICP sources, and the use of different diluents for improving ICP analyses. Considering the data from all sample groups all analysis techniques investigated (except ferrography and the acid dissolution method) were iron particle size sensitive. None of the techniques offered any improvement over the currently used AE with respect to analyzing large particles, monitoring capability with or without microfiltration, analysis time or analysis cost or person-power. The study also indicated that microfiltration could have a small effect on spectrometric oil analysis results.

Saba, C.S.; Smith, H.A.; Kauffman, R.E.

1992-04-01

151

Agglomerating self-cleaning air cleaner. Final report  

Microsoft Academic Search

This report describes an experimental program to evaluate an agglomerating self-cleaning air cleaner concept for application to diesel-powered tactical trucks and combat vehicles. Technical feasibility was evaluated through laboratory testing of candidate agglomerating media and through a design parameter component study of the agglomerator, inertial separator, and final filter integration and system operation. Several factors were used to evaluate media

Treuhaft

1985-01-01

152

Apparatus and method for compacting, degassing and carbonizing carbonaceous agglomerates  

Microsoft Academic Search

An apparatus for compacting, degassing and carbonizing carbonaceous agglomerates is described. The apparatus comprises a rotary kiln having an agglomerate inlet means for introducing green agglomerates into the kiln near the inlet of the kiln and a heating medium inlet for introducing a heating medium comprising a finely divided solid into the kiln at a preselected location intermediate the inlet

1980-01-01

153

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

154

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

155

Technical constraints limiting application of enhanced oil recovery techniques to petroleum production in the United States  

SciTech Connect

In the interval since the publication in September 1980 of the technical constraints that inhibit the application of enhanced oil recovery techniques in the United States, there has been a large number of successful field trials of enhanced oil recovery (EOR) techniques. The Department of Energy has shared the costs of 28 field demonstrations of EOR with industry, and the results have been made available to the public through DOE documents, symposiums and the technical literature. This report reexamines the constraints listed in 1980, evaluates the state-of-the-art and outlines the areas where more research is needed. Comparison of the 1980 constraints with the present state-of-the-art indicates that most of the constraints have remained the same; however, the constraints have become more specific. 26 references, 6 tables.

Not Available

1984-01-01

156

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

157

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, Craig D.

1999-11-01

158

Comparing effectiveness of rhamnolipid biosurfactant with a quaternary ammonium salt surfactant for hydrate anti-agglomeration.  

PubMed

Natural gas is projected to be the premium fuel of the 21st century because of availability, as well as economical and environmental considerations. Natural gas is coproduced with water from the subsurface forming gas hydrates. Hydrate formation may result in shutdown of onshore and offshore operations. Industry practice has been usage of alcohols--which have undesirable environmental impacts--to affect bulk-phase properties and inhibit hydrate formation. An alternative to alcohols is changing the surface properties through usage of polymers and surfactants, effective at 0.5-3 wt % of coproduced water. One group of low-dosage hydrate inhibitors (LDHI) are kinetic inhibitors, which affect nucleation rate and growth. A second group of LDHI are anti-agglomerants, which prevent agglomeration of small hydrate crystallites. Despite great potential, reported work on hydrate anti-agglomeration is very limited. In this paper, our focus is on the use of two vastly different surfactants as anti-agglomerants. We use a model oil, water, and tetrahydrofuran as a hydrate-forming species. We examine the effectiveness of a quaternary ammonium salt (i.e., quat). Visual observation measurements show that a small concentration of the quat (0.01%) can prevent agglomeration. However, a quat is not a green chemical and therefore may be undesirable. We show that a rhamnolipid biosurfactant can be effective to a concentration of 0.05 wt %. One difference between the two surfactants is the stability of the water-in-oil emulsions created. The biosurfactant forms a less stable emulsion, which makes it very desirable for hydrate application. PMID:18171051

York, J Dalton; Firoozabadi, Abbas

2008-01-03

159

Geographical agglomeration and co-agglomeration of foreign and domestic enterprises: a case study of Chinese manufacturing industries  

Microsoft Academic Search

Industrial agglomeration has been pervasive owing to natural advantages, spillover effects and institutional advantages. The co-agglomeration of foreign and domestic enterprises may be a driving force of intra-industrial agglomeration. Theories however provide conflicting predictions on whether foreign and domestic enterprises share similar locations. Based on data from the Annual Survey of Industrial Firms in 2005 in China, this study finds

Canfei He; Junsong Wang

2010-01-01

160

ANN and wavelet-based discrimination technique between discharge currents in transformer mineral oils  

NASA Astrophysics Data System (ADS)

This paper is aimed at the analysis of positive pre-breakdown currents triggered in mineral transformer oil submitted to 50 Hz alternating overvoltages. Different shapes of streamer currents and electrical discharges have been recorded to develop a discrimination technique based on an Artificial Neural Network (ANN) and Wavelet analysis of these currents. This enables us to address a complementary diagnosis tool that can serve as an online transformer monitoring and protection.

Aberkane, F.; Moulai, H.; Nacer, A.; Benyahia, F.; Beroual, A.

2012-05-01

161

Application of thermal techniques in the recovery of heavy minerals from oil-sand tailings  

Microsoft Academic Search

Thermal techniques, namely, thermogravimetry (TG), simultaneous thermogravimetry-differential thermal analysis-Fourier transform infrared spectroscopy (TG-DTA-FTIR) and thermomagnetometry, were used to examine the thermal behaviour of heavy-mineral tailings generated in oil-sand steam processing operations. The results will be used in the selection and optimization of a thermal process to remove residual bitumen in the tailings and recover the contained titanium and zirconium values.

Shaheer A. Mikhail; Anne-Marie Turcotte; Colin A. Hamer

1996-01-01

162

Gas hydrate anti-agglomerant properties of polypropoxylates and some other demulsifiers  

Microsoft Academic Search

Low dosage hydrate inhibitors (LDHIs) have been developed over the last 15 yr as a new gas hydrate control technology for the oil industry, which can be more cost-effective than traditional practices such as the use of thermodynamic inhibitors e.g. methanol and glycols. Two classes of LDHI called kinetic inhibitors (KHIs) and anti-agglomerants (AAs) are already being successfully used in the

Malcolm A. Kelland; Thor Martin Svartås; Lindy Dybvik Andersen

2009-01-01

163

AN INVESTIGATION OF DIESEL ENGINE OIL FILTRATION AND ABRASIVE WEAR WITH HIGH DETERGENCY LUBRICANTS BY MEANS OF RADIOACTIVE TRACER TECHNIQUES  

Microsoft Academic Search

A study designed to evaluate the relative effects of fullflow and bypass ; filtration, abrasive particle size, and detergent additive level of diesel ; lubricating oils on piston ring wear in a General Motors 3-71 type diesel engine ; was conducted using radioisotope tracer techniques. The detergent-type oils ; greatly reduced the amount of piston ring wear in comparison to

Halliwell

1959-01-01

164

Positive Displacement Archimedes' Screw Pumps and Flow Enhancing Techniques. Essential Tools in Response to Spills of Heavy Oil and Bitumen  

Microsoft Academic Search

The perspective of this paper is to provide responders and authorities with a broader understanding of the most advanced pumping technologies and techniques that are available for one of the most difficult tasks in mechanical response to spills of heavy and extreme viscosity oil: Extreme viscosity transfer pumping. The so-called positive displacement Archimedes' screw (PDAS) pumps have within the oil

Flemming Hvidbak

165

Optical Characterization of Crude Oils and Dispersant Used in the Northern Gulf of Mexico by Fluorescence EEM Techniques  

Microsoft Academic Search

During the unprecedented oil spill in the northern Gulf of Mexico between April and July 2010, ~8 x 108 liters of crude oil and ~7 x 106 liters of dispersant were released into the water column in the Gulf of Mexico. Fluorescence excitation and emission matrix (EEM) techniques and CDOM measurements have been used in many studies to examine the

L. Guo; Z. Zhuo; A. M. Shiller; S. E. Lohrenz

2010-01-01

166

Determination of peroxide value of edible oils by FTIR spectroscopy with the use of the spectral reconstitution technique  

Microsoft Academic Search

Spectral reconstitution (SR), a technique that has been developed to facilitate mid-FTIR transmission analysis of inherently viscous samples, was applied to simplify and automate a previously reported FTIR method for the determination of peroxide value (PV) of edible oils. The basis of the PV determination is the rapid reaction of triphenylphosphine (TPP) with the hydroperoxides present in an oil to

Xiuzhu Yu; F. R. van de Voort; J. Sedman

2007-01-01

167

Establishing structure–property correlations and classification of base oils using statistical techniques and artificial neural networks  

Microsoft Academic Search

The present paper describes various classification techniques like cluster analysis, principal component (PC)\\/factor analysis to classify different types of base stocks. The API classification of base oils (Group I–III) has been compared to a more detailed NMR derived chemical compositional and molecular structural parameters based classification in order to point out the similarities of the base oils in the same

G. S Kapur; M. I. S Sastry; A. K Jaiswal; A. S Sarpal

2004-01-01

168

Agglomeration rate and action forces between atomized particles of agglomerator and inhaled-particles from coal combustion.  

PubMed

In order to remove efficiently haled-particles emissions from coal combustions, a new way was used to put forward the process of agglomeration and the atomization was produced by the nozzle and then sprayed into the flue before precipitation devices of power station boiler in order to make inhaled-particles agglomerate into bigger particles, which can be easily removed but not change existing running conditions of boiler. According to this idea, a model is set up to study agglomeration rate and effect forces between fly ash inhaled-particles and atomized agglomerator particles. The developed agglomeration rate was expressed by relative particle number decreasing speed per unit volume. The result showed that viscosity force and flow resistance force give main influences on agglomeration effect of inhaled-particles, while springiness force and gravity have little effect on agglomeration effect of theirs. Factors influencing the agglomeration rate and effect forces are studied, including agglomerator concentration, agglomerator flux and agglomerator density, atomized-particles diameters and inhaled-particles diameter and so on. PMID:16295917

Wei, Feng; Zhang, Jun-ying; Zheng, Chu-guang

2005-01-01

169

Sonic enhanced ash agglomeration and sulfur capture  

SciTech Connect

The major objective of the Phase 1 test program is to confirm the feasibility of the Manufacturing and Technology Conversion International, Inc. 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. Phase 1 tests are designed to cover the frequency range between 50 and 1400 Hz, establish monomodal baseline performance as a benchmark from which to measure the degree of enhancement expected from the bimodal approach, and, finally, to confirm the effectiveness of low-frequency fields over high-frequency fields for realistic particulate streams. 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. Under the impact of high-intensity sound waves, sorbent reactivity and utilization, it is theorized, will increase while agglomerates of fly ash and sorbents are formed which are readily collected in commercial cyclones. 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. For Phase 1, Pennsylvania State University will conduct studies for enhanced sulfur capture in The Combustion Laboratory and agglomeration tests in the High Intensity Acoustic Laboratory. 2 refs., 43 figs., 7 tabs.

Not Available

1991-01-01

170

Encapsulation of hazardous wastes into agglomerates  

SciTech Connect

The objective of this study was to investigate the feasibility of using the cementitious properties and agglomeration characteristics of coal conversion byproducts to encapsulate and immobilize hazardous waste materials. The intention was to establish an economical way of co-utilization and co-disposal of wastes. In addition, it may aid in the eradication of air pollution problems associated with the fine-powdery nature of fly ash. Encapsulation into agglomerates is a novel approach of treating toxic waste. Although encapsulation itself is not a new concept, existing methods employ high-cost resins that render them economically unfeasible. In this investigation, the toxic waste was contained in a concrete-like matrix whereby fly ash and other cementitious waste materials were utilized. The method incorporates the principles of solidification, stabilization and agglomeration. Another aspect of the study is the evaluation of the agglomeration as possible lightweight aggregates. Since fly ash is commercially used as an aggregate, it would be interesting to study the effect of incorporating toxic wastes in the strength development of the granules. In the investigation, the fly ash self-cementation process was applied to electroplating sludges as the toxic waste. The process hoped to provide a basis for delisting of the waste as hazardous and, thereby greatly minimize the cost of its disposal. Owing to the stringent regulatory requirements for hauling and disposal of hazardous waste, the cost of disposal is significant. The current practice for disposal is solidifying the waste with portland cement and dumping the hardened material in the landfill where the cost varies between $700--950/ton. Partially replacing portland cement with fly ash in concrete has proven beneficial, therefore applying the same principles in the treatment of toxic waste looked very promising.

Guloy, A.

1992-01-28

171

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

172

Removal of Cu(II) from Aqueous Solution by Oil-Water Interfacial Emulsion Technique with Adsorbing Colloids  

Microsoft Academic Search

Experimental investigations on the removal of Cu(II) from an aqueous solution were carried out by an interfacial emulsion technique with an adsorbing colloid (Al(OH)3, FE(OH)3), Cu(II) from the aqueous solution was segregated into a compact emulsion between water and a water-immiscible oil phase by an interfacial emulsion technique that uses the adsorptive power of the oil-water interface. Trimethylamine was effective

Won Sik Shin; Sang June Choi

1994-01-01

173

Micro-agglomerate flotation for deep cleaning of coal. Quarterly progress report, July 1, 1995--September 30, 1995  

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 mm) needed to achieve adequate liberation of the mineral matter from the coal matrix. It is generally recognized that surface-based separation processes such as froth flotation or selective agglomeration offer considerable potential for such applications but there remain many problems in obtaining the required selectivity with acceptable recovery of combustible matter. In froth flotation, selectivity is substantially reduced at fine sizes due, primarily, to overloading of the froth phase which leads to excessive carryover of water and entrained mineral matter. Oil agglomeration, on the other hand, can provide good selectivity at low levels of oil addition but the agglomerates tend to be too fragile for separation by the screening methods normally used. The addition of larger amounts of oil can yield large, strong agglomerates which are easily separated but the selectivity is reduced and reagent costs can become excessive.

Chander, S.; Hogg, R.

1995-07-01

174

Combustion studies of coal-in-oil droplets. Final report, August 1, 1977-July 31, 1979  

SciTech Connect

The combustion characteristics of droplets of coal-oil mixtures (COM) were investigated both theoretically and experimentally. Results show that agglomeration of the coal powder occurs upon complete depletion of the volatile oil components, and therefore has serious implications regarding radiation transfer, total burning time, and particulate collection efficiency. Agglomeration is somewhat irrelevant for COM with No. 6 oil because of the small volatility-differentials between coal and No. 6 oil. As a result of agglomeration, fine-crushing the coal is unnecessary unless they can be reduced to micron-sizes such that agglomerate ignition is facilitated.

Law, C.K.

1979-12-01

175

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

SciTech Connect

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, and higher viscosities than their non-biodegraded counterparts. Oil quality (API gravity and acid number) has a significant impact on the development economics. It is important to obtain as much geochemical information as possible from the limited volume of oil contained in conventional sidewall samples because borehole conditions often preclude the possibility of running a wireline test tool (the MDT) to obtain a fluid sample. An analytical program of PFID (Pyrolysis Flame Ionization Detection), TEC (Thermal Extraction Chromatography) and NIR (Near Infra-Red spectroscopy) was conducted on a set of {open_quote}calibration{close_quote} oils and the data were used to develop both empirical and quantitative predictive criteria for estimating crude oil properties of gravity, acid number, sulfur content, and viscosity. Sidewall samples provide sufficient material for these micro-analytical techniques. The individual sidewalls were split for geochemical analysis with the remaining material available for petrographic analysis. The PFID and TEC techniques were run on the {open_quote}rock{close_quote} sample containing the oil. For the NIR technique, the oil was extracted from the sample with an organic solvent and the extract evaluated. Results will be presented for sidewall core samples obtained from four oil sands encountered during a two well exploratory program.

Bement, W.O.; McNeil, R.I. [Shell Development Co., Houston, TX (United States); Lippincott, R.G. [Shell Offshore Inc., New Orleans, LA (United States)

1996-08-01

176

Agglomeration of calcium oxalate monohydrate in synthetic urine.  

PubMed

The development of agglomerated particles of calcium oxalate monohydrate (COM) on the semi-batch precipitation from a synthetic urine carried out at physiological conditions (37 degrees C, pH = 5.5) was studied by optical and electron scanning microscopy. COM agglomerates develop by primary and secondary agglomeration proceeding simultaneously; the latter mechanism is, however, less important than the former. Citrate ions modify slightly the COM crystal shape and inhibit primary agglomeration. Mucin particles serve as a substrate for preferential formation (nucleation) of new COM crystals. The structure of formed agglomerates closely resembles that of a certain type of COM renal calculi. A combination of primary agglomeration of crystals forming stones and nucleation of new crystals on a mucoprotein layer partially covering their surface constitutes the possible mechanism of such stone development. Experimental data support this mechanism. PMID:1422681

Grases, F; Masárová, L; Söhnel, O; Costa-Bauzá, A

1992-09-01

177

Method for agglomerating coal particles in pulp water  

SciTech Connect

Coal particles are agglomerated in pulp water of coal particles by agitating the pulp water in the presence of a binder, which comprises conducting agglomeration in a plurality of zones, the zones being communicated one after another, and transferring the pulp water from one zone to another while agitating the pulp water in each zone and increasing a pulp concentration of the pulp water from one zone to another. Agitating power for the agglomeration is reduced with the successively increasing pulp concentration.

Hiratsuka, K.; Kurihara, M.; Maruko, M.; Matsuura, Y.; Nakamura, Y.

1985-01-08

178

A new process based agglomeration parameter to characterize ceramic powders  

Microsoft Academic Search

Uranium dioxide powders are made through aqueous chemical route involving precipitation, drying, calcination and reduction. The presence of agglomerates causes powder packing difficulties in the compaction die, and non-uniform and incomplete densification on sintering. To quantify the degree of agglomeration, several authors have proposed ‘Agglomeration Parameters’. The change in BET specific surface area of calcined U3O8 upon reduction to UO2

Palanki Balakrishna; B. Narasimha Murty; M. Anuradha

2009-01-01

179

Deciphering the effects of agglomeration economies on firms’ productive efficiency  

Microsoft Academic Search

The present work assess the effects of MAR and Jacob’s type agglomeration economies on a sample of firms in the machineries and textiles industries in Greece for the periods 1989-91 and 1999-01. The analysis employs a stochastic production frontier function and allows agglomeration economies to enter as inputs and\\/or as factors reducing inefficiency. Results re-confirm that the effects of agglomeration

Dimitris Skuras; Kostas Tsekouras; Efthalia Dimara

2011-01-01

180

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

181

Agglomeration defects on irradiated carbon nanotubes  

SciTech Connect

Aligned carbon nanotubes (CNT) were irradiated in the longitudinal and perpendicular directions, with low energy carbon and helium ions in order to observe the formation of defects in the atomic structure. Analysis through Raman spectroscopy and scanning electron microscopy indicated bundle rupture and ion track formation on nanotube bundles. Aligned CNT presented a kind of defect comprising ravine formation and tube agglomeration on top of the substrate. The latter structure is possibly caused by static charge accumulation induced by the incoming ions. Fluence plays a role on the short range order. Higher fluence irradiation transforms CNT into amorphous carbon nanowires.

Steini Moura, Cassio [Faculty of Physics, Pontificia Universidade Catolica do Rio Grande do Sul, 90619-900, Porto Alegre, RS (Brazil); Balzaretti, Naira Maria; Amaral, Livio [Institute of Physics, Universidade Federal do Rio Grande do Sul, C.P.: 15051, 91501-070, Porto Alegre, RS (Brazil); Gribel Lacerda, Rodrigo; Pimenta, Marcos A. [Universidade Federal de Minas Gerais, C.P.: 702, 31270-901, Belo Horizonte, MG (Brazil)

2012-03-15

182

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

183

Techniques to Improve Cyclic Steam Stimulation of Deep and Extra Heavy Oil Reservoirs in Xiaowa Oil Field  

Microsoft Academic Search

Xiaowa oil field is a fault nose in structure with sandstone res- ervoirs, in which 9.7km 2 oil-bearing area and 3627 × 10 4 t original oil in place is proved. The pay zones that have been developed are Dongying Group and S3 of lower Tertiary. Dongying Group belongs to delta-front regime with good physical properties. S3 belongs to submerged

Cheng Jincai; Yu Hongkun; Yang Xianke; Liu Guiman

1998-01-01

184

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

185

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

186

Optical Properties of Some Silicone Diffusion-Pump Oils in the Vacuum Ultraviolet—Using a Closed-Cell Technique  

Microsoft Academic Search

The optical properties of Dow Corning-704 and -705 diffusion-pump oils have been measured from 2?10.6 eV using a closed-cell technique. The data are interpreted in terms of molecular excitations of ?, ?, and nonbonding electrons in the complex pump oil molecules and in terms of collective oscillations of electrons in the liquids. The optical constants of Dow Corning-200, another silicone

B. L. Sowers; M. W. Williams; R. N. Hamm; E. T. Arakawa

1971-01-01

187

Collisions between equal-sized ice grain agglomerates  

Microsoft Academic Search

Context: Following the recent insight in the material structure of comets, protoplanetesimals are assumed to have low densities and to be highly porous agglomerates. It is still unclear if planetesimals can be formed from these objects by collisional growth. Aims: Therefore, it is important to study numerically the collisional outcome from low velocity impacts of equal sized porous agglomerates which

C. Schäfer; R. Speith; W. Kley

2007-01-01

188

Technological Capability, Agglomeration Economies and Firm Location Choice  

Microsoft Academic Search

Jo Y. and Lee C.-Y. Technological capability, agglomeration economies and firm location choice, Regional Studies. This paper argues that a firm's ability to produce and absorb technological knowledge, or technological capability, influences its choice of location among regions characterized by different types of agglomeration. This paper found that geographically bounded knowledge externalities, one of the forces that attract firms into

Yuri Jo; Chang-Yang Lee

2012-01-01

189

Wet agglomeration of powders: from physics toward process optimization  

Microsoft Academic Search

A general method to optimize a wet powder agglomeration process for achieving desired properties of granulated products is suggested. The different states of a wet powder are characterized by a cohesion function, i.e. the evolution of the torque of the stirred system as a function of the moisture content. Two different types of agglomeration behaviours are shown: Stepwise Growing Behaviour

Alexandre Goldszal; Jacques Bousquet

2001-01-01

190

Agglomeration Economies: Microdata Panel Estimates from Canadian Manufacturing  

Microsoft Academic Search

Productivity and wages tend to be higher in cities. This is typically explained by agglomeration economies, which increase the returns associated with urban locations. Competing arguments of specialization and diversity undergird these claims. Empirical research has long sought to confirm the existence of agglomeration economies and to adjudicate between the models of Marshall, Arrow and Romer (MAR) that suggest the

John R. Brown W. Mark Rigby David Baldwin

2008-01-01

191

Chapter 38 Agglomeration economies and urban public infrastructure  

Microsoft Academic Search

This chapter reviews the theoretical and empirical literature on agglomeration economies and urban public infrastructure. Theory links the two concepts by positing that agglomeration economies exist when firms in an urban area share a public good as an input to production. One type of shareable input is the close proximity of businesses and labor, that generates positive externalities which in

Daniel P. McMillen

1999-01-01

192

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

SciTech Connect

The Bluebell field is productive from the Tertiary lower Green River and Colton (Wasatch) Formations of the Uinta Basin, Utah. The productive interval consists of thousands of feet of interbedded fractured clastic and carbonate beds deposited in the ancestral Lake Uinta. Wells in the Bluebell field are typically completed by perforating 40 or more beds over 1000 to 3000 vertical ft (300-900 m), then stimulating the entire interval with hydrochloric acid. This technique is often referred to as the shot gun completion. Completion techniques used in the Bluebell field were discussed in detail in the Second Annual Report (Curtice, 1996). The shot-gun 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. A two-year characterization study involved detailed examination of outcrop, core, well logs, surface and subsurface fractures, produced oil-field waters, engineering parameters of the two demonstration wells, and analysis of past completion techniques and effectiveness. The study was intended to improve the geologic characterization of the producing formations and thereby develop completion techniques specific to the producing beds or facies instead of a shot gun approach to stimulating all the beds. The characterization did not identify predictable-facies or predictable-fracture trends within the vertical stratigraphic column as originally hoped. Advanced logging techniques can identify productive beds in individual wells. A field-demonstration program was developed to use cased-hole advanced logging techniques in two wells and recompletion the wells at two different scales based on the logging. The first well was going to be completed at the interval scale using a multiple stage completion technique (about 500 ft [150 m] per stage). The second well will be recompleted at the bed-scale using bridge plug and packer to isolate three or more beds for stimulation. These recompletion will show which logs are most effective in identifying productive beds and what scale of completion is most cost effective. The third demonstration will be the logging and completion of a new well using the logs and completion scale or technique, most effective in the previous demonstrations.

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

1998-04-01

193

Bed material agglomeration during fluidized bed combustion. Final report  

SciTech Connect

The purpose of this project is to determine the physical and chemical reactions which lead to the undesired agglomeration of bed material during fluidized bed combustion of coal and to relate these reactions to specific causes. A survey of agglomeration and deposit formation in industrial fluidized bed combustors (FBCs) indicate that at least five boilers were experiencing some form of bed material agglomeration. Deposit formation was reported at nine sites with deposits most commonly at coal feed locations and in cyclones. Other deposit locations included side walls and return loops. Three general types of mineralogic reactions were observed to occur in the agglomerates and deposits. Although alkalies may play a role with some {open_quotes}high alkali{close_quotes} lignites, we found agglomeration was initiated due to fluxing reactions between iron (II) from pyrites and aluminosilicates from clays. This is indicated by the high amounts of iron, silica, and alumina in the agglomerates and the mineralogy of the agglomerates. Agglomeration likely originated in the dense phase of the FBC bed within the volatile plume which forms when coal is introduced to the boiler. Secondary mineral reactions appear to occur after the agglomerates have formed and tend to strengthen the agglomerates. When calcium is present in high amounts, most of the minerals in the resulting deposits are in the melilite group (gehlenite, melilite, and akermanite) and pyroxene group (diopside and augite). During these solid-phase reactions, the temperature of formation of the melilite minerals can be lowered by a reduction of the partial pressure of CO{sub 2} (Diopside + Calcite {r_arrow}Akermanite).

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

1996-01-01

194

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

195

[Artificial neural network forecasting method in monitoring technique by spectrometric oil analysis].  

PubMed

The spectrometric oil analysis (SOA) is an important technique for machine state monitoring and fault diagnosis, and forecasting machine state through SOA results has an advantage of finding out machine system wear fault early. Because Artificial Neural Network (ANN) possesses obvious advantages over traditional forecasting models for identifyingnon-linear model and forecasting non-even signal, the ANN forecasting approach was applied to monitoring technique by SOA, and the monitoringtechnique by SOA based on ANN forecasting was put forward. In the forecasting model, a 3-layer BP network structure was adopted.Aiming at the problem that ANN structure has a great effect on forecasting precision, the authors utilized the Genetic Algorithm (GA) to optimize the node number of input layer, the node number of hidden layer, and MSE (Mean of Squared Error) target value which was required for ANN training, and obtained the optimum forecasting model of ANN. Finally, the practical SOA data of some engine was analyzed and forecasted by ANN, and the forecasting result was compared with that of traditional ARMA model. The result fully showsthe superiority and effectivity of the new method. PMID:16329517

Yang, Yu-wei; Chen, Guo; Yang, Yu-wei; Chen, Guo

2005-08-01

196

Technique to Improve Fuel Extraction for Coal Seams Intersected by Oil and Gas Wells.  

National Technical Information Service (NTIS)

Coal, gas, and oil in many geological formations of the eastern United States are intimately associated but have traditionally been recovered independently of each other. Oil and gas wells, however, are often spaced sufficiently close to cause the subsequ...

R. D. Haynes

1974-01-01

197

Direct Observation of Oil Consumption Mechanisms in a Production Spark Ignition Engine Using Fluorescence Techniques.  

National Technical Information Service (NTIS)

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-in...

R. M. Lusted

1994-01-01

198

Novel Binders and Methods for Agglomeration of Ore  

SciTech Connect

Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily at a reasonable cost. A primary example of this is copper heap leaching, where there are no binders currently encountered in this acidic environment process. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching. The active involvement of our industrial partners will help to ensure rapid commercialization of any agglomeration technologies developed by this project.

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

2005-09-30

199

Novel Binders and Methods for Agglomeration of Ore  

SciTech Connect

Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily at a reasonable cost. A primary example of this is copper heap leaching, where there are no binders currently encountered in this acidic environment process. As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching. The active involvement of our industrial partners will help to ensure rapid commercialization of any agglomeration technologies developed by this project.

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

2006-03-31

200

Enhanced oil recovery - polymer-caustic: Mitchell develops combination technique to improve recovery rates  

Microsoft Academic Search

A new enhanced oil recovery method involving the injection of polymers followed by a polymer-caustic mix may produce as much as 10% to 15% more oil from some formations. While polymers and caustics have been used for additional oil recovery for a number of years, combining the 2 is the unique part of the new process. The mixture allows both

Wash

1982-01-01

201

Re-Refined Lubricating Base Oil Characterization Using Liquid Chromatographic Techniques.  

National Technical Information Service (NTIS)

A separation scheme to characterize lubricating base oils in terms of molecular compound classes has been developed with the purpose of isolating and analyzing impurities in a re-refined base oil. The lubricating base oil is first separated into three maj...

P. Pei S. M. Hsu

1984-01-01

202

Use of high-resolution geophysical techniques for the emplacement of abandoned oil and gas platforms as artificial reefs  

Microsoft Academic Search

The Louisiana Artificial Reef Program established in 1986, utilizes abandoned oil and gas platforms as artificial reefs. Many factors are considered for site evaluation with the main focus on high-resolution (3.5-12 kHz echograms, single channel seismic, and side-scan sonar) geophysical techniques. By employing these techniques in conjunction with geotechnical information, an accurate determination of potentially hazardous and unstable geologic conditions

1988-01-01

203

A semi-coarsening strategy for unstructured multigrid based on agglomeration  

NASA Astrophysics Data System (ADS)

Extending multigrid concepts to the calculation of complex compressible flow is usually not straightforward. This is especially true when non-embedded grid hierarchies or volume agglomeration strategies are used to construct a gradation of unstructured grids. In this work, a multigrid method for solving second-order PDEs on stretched unstructured triangulations is studied. The finite volume agglomeration multigrid technique originally developed for solving the Euler equations is used (M.-H. Lallemand and A. Dervieux, in Multigrid Methods, Theory, Applications and Supercomputing, Marcel Dekker, 337-363 (1988)). First, a directional semi-coarsening strategy based on Poissons equation is proposed. The second-order derivatives are approximated on each level by introducing a correction factor adapted to the semi-coarsening strategy. Then, this method is applied to solve the Poisson equation. It is extended to the 2D Reynolds-averaged Navier-Stokes equations with appropriate boundary treatment for low-Reynolds number turbulent flows.

Francescatto, Jerome; Dervieux, Alain

1998-04-01

204

Agglomeration processes sustained by dust density waves in Ar/C2H2 plasma: From C2H2 injection to the formation of an organized structure  

NASA Astrophysics Data System (ADS)

In this paper, an experimental investigation of dust particle agglomeration in a capacitively coupled RF discharge is reported. Carbonaceous particles are produced in an argon plasma using acetylene. As soon as the particle density becomes sufficient, dust density waves (DDWs) are spontaneously excited within the cathode sheath. Recently, it was proven that DDWs can significantly enhance the agglomeration rate between particles by transferring them a significant kinetic energy. Thus, it helps them to overcome Coulomb repulsion. The influence of this mechanism is studied from acetylene injection to the formation of very large agglomerates forming an organized structure after a few dozens of seconds. For this purpose, three diagnostic tools are used: extinction measurements to probe nanometer-sized particles, fast imaging for large agglomerates and a dust extraction technique developed for ex-situ analysis.

Dap, Simon; Hugon, Robert; Lacroix, David; de Poucques, Ludovic; Briancon, Jean-Luc; Bougdira, Jamal

2013-03-01

205

Investigation into the impact of sub-populations of agglomerates on the particle size distribution and flow properties of conventional microcrystalline cellulose grades.  

PubMed

Microcrystalline cellulose (MCC) is regarded as one of the most versatile tablet filler binders, finding a wide use in both granulation and direct compression operations. It has been shown that MCC particle populations consist of a mixture of 'rod like' primary particles, and agglomerates, and that the proportion of these primary particles and agglomerates differs within the different grades of materials, contributing to the different bulk properties of these materials. However, the proportion of primary particles and agglomerates has not previously been fully elucidated, and their contribution to the performance factors such as flow explained. In this paper we use a novel microscopy-based characterization technique to demonstrate that the proportion of 'agglomerates' in the series of MCC grades between PH101 and PH200 is, by number, very low, but sufficient to perturb a volume-based particle size method by significant amounts. PMID:20565228

Gamble, John F; Chiu, Wing-Sin; Tobyn, Mike

2010-06-21

206

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

207

Shale oil stabilization with a hydroprocessor  

Microsoft Academic Search

A process is provided to produce, stabilize, dedust and upgrade synthetic oil, such as shale oil. In the process, synthetic fuels, such as oil shale, tar sands and diatomite are retorted with heat carrier material to liberate an effluent product stream comprising hydrocarbons and entrained particulates of dust. In order to minimize polymerization of the product stream and agglomerate the

E. D. York; D. M. Johnson; P. B. Miller

1985-01-01

208

Statistical simulation of aluminum agglomeration during combustion of heterogeneous condensed mixtures  

Microsoft Academic Search

A statistical model of aluminum agglomeration during combustion of solid composite rocket propellants is considered; the model describes the process dynamics, beginning from propellant heating in the combustion wave and ending by separation of agglomerates from the burning surface. An algorithm of computing the agglomeration process by the Monte Carlo method is proposed. A series of computations of aluminum agglomeration

S. A. Rashkovskii

2005-01-01

209

The degree and kind of agglomeration affect carbon nanotube cytotoxicity.  

PubMed

The urgent need for toxicological studies on carbon nanotubes (CNTs) has arisen from the rapidly emerging applications of CNTs well beyond material science and engineering. In order to provide a basis for comparison to existing epidemiological data, we have investigated CNTs at various degrees of agglomeration using an in vitro cytotoxicity study with human MSTO-211H cells. Non-cytotoxic polyoxyethylene sorbitan monooleate was found to well-disperse CNT. In the present study, the cytotoxic effects of well-dispersed CNT were compared with that of conventionally purified rope-like agglomerated CNTs and asbestos as a reference. While suspended CNT-bundles were less cytotoxic than asbestos, rope-like agglomerates induced more pronounced cytotoxic effects than asbestos fibres at the same concentrations. The study underlines the need for thorough materials characterization prior to toxicological studies and corroborates the role of agglomeration in the cytotoxic effect of nanomaterials. PMID:17169512

Wick, Peter; Manser, Pius; Limbach, Ludwig K; Dettlaff-Weglikowska, Ursula; Krumeich, Frank; Roth, Siegmar; Stark, Wendelin J; Bruinink, Arie

2006-11-19

210

Industrial agglomeration and transport accessibility in metropolitan Seoul  

NASA Astrophysics Data System (ADS)

This study aims to reveal the relationship between industrial agglomeration and transport accessibility in the Seoul metropolitan area. Our study suggests that in spite of the rapid expansion of the Seoul metropolitan area, central business districts still function as centers of the industry and transportation system; the agglomeration of most industrial subsectors are occurring in central areas and only primary and manufacturing sectors' clusters are located out of these areas; both of subway and road networks show higher level of accessibility in central Seoul and big cities. This implies a strong relationship between the industrial agglomeration and the transport accessibility, and such hypothetical relationship is tested for every industrial subsector using logit analysis. Our findings indicate that although there are industrial variations in the magnitude of impacts and the significance level, transport networks are, in general, positively associated with industrial agglomeration and this is especially true for service sectors.

Song, Yena; Lee, Keumsook; Anderson, William P.; Lakshmanan, T. R.

2012-07-01

211

Overpopulated, Underdeveloped Urban Agglomerations: Tomorrow's 'Unstable' Operating Environment.  

National Technical Information Service (NTIS)

This paper asserts that a unique future operational environment is developing: overpopulated, underdeveloped, urban agglomerations. A proposed definition for this operating environment is as follows: an overpopulated urban area that is located within a de...

M. A. Stoker

2012-01-01

212

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

2009-10-29

213

Study of the re-oiling process of hair with the replica technique.  

PubMed

Synopsis In the case of individuals with oily hair, the sebum excreted to the scalp surface spreads over the hair during the days following hair washing. The migration of sebum from the roots to the ends of hairs creates a gradient which may be measured by making casts on appropriate materials. An optical reading device enables the assessment of the alterations of the material brilliancy as a function of the sebum presence. The following parameters may be assessed from the recording: length of the cast, surface, height and width of the peak. Thus, different types of oily states may be identified according to: - the number of days after the last shampoo; - the characteristics of sebum (e.g. quantity, viscosity); - the features of hair. The casts reflect the oily state of hair as accurately as if it were assessed with a sensory method. Thus, this technique enables the study and comparison of oily states. It can be used to determine the efficacy of products having an effect on the re-oiling process of hair. PMID:19457224

Courtois, M; Krien, P; Meyronne, L; Grollier, J F

1986-12-01

214

Industrial agglomeration and transport accessibility in metropolitan Seoul  

Microsoft Academic Search

This study aims to reveal the relationship between industrial agglomeration and transport accessibility in the Seoul metropolitan\\u000a area. Our study suggests that in spite of the rapid expansion of the Seoul metropolitan area, central business districts still\\u000a function as centers of the industry and transportation system; the agglomeration of most industrial subsectors are occurring\\u000a in central areas and only primary

Yena Song; Keumsook Lee; William P. Anderson; T. R. Lakshmanan

2012-01-01

215

Mechanistic studies of nanocluster nucleation, growth, and agglomeration  

Microsoft Academic Search

Following a critical review of the relevant literature, the research presented herein focuses on the mechanisms by which transition-metal nanoclusters nucleate, grow, and agglomerate. The studies include: (i) the generality of the recently uncovered, 4-step mechanism for nanocluster formation and agglomeration; (ii) a study addressing the question of whether the hydrogenation of olefins using (1,5-COD)PtII complexes proceeds via homogeneous or

Eric E. Finney

2009-01-01

216

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

217

Testing thermoanthracite fines as a fuel for an agglomeration process  

SciTech Connect

An investigation was presented on the use of thermoanthracite fines as a raw material for the agglomeration process in place of coke fines. The thermoanthracite tested was produced in the calcination of anthracite concentration from a washery of the 70-25 mm size class. It was found that the agglomerate produced on thermoanthracite fines was superior to that from anthracite fines and near that from coke fines with respect to strength and granulometric composition.

Ulanovskii, M.L.; Mal'ko, N.I.; Boiko, M.G.; Tseitlin, M.A.; Tuktamyshev, I.S.; Ivanov, A.N.; Krishtopa, A.P.; Bort, P.I.; Kucher, M.G.

1982-01-01

218

Evaluation method for agglomerating properties of granular detergents  

Microsoft Academic Search

A new method for evaluating the agglomerating property of granular detergents was devised. It is useful for comparing commercial\\u000a products, screening new products, and for studying anticaking agents. This method differs from prior methods, as detergent\\u000a is fluidized by conditioned air in a reverse conical tower, and agglomeration is evaluated from the lowering of level of fluidized\\u000a particles because of

Toshio Nagai; Hiromu Onzuka

1968-01-01

219

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

NASA Astrophysics Data System (ADS)

The design specifications for the HTHP AA Facility are listed. 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 Pen State University's High Intensity Acoustic Laboratory.

1985-08-01

220

Evolution of Zipf's Law for Indian Urban Agglomerations Vis-à-Vis Chinese Urban Agglomerations  

NASA Astrophysics Data System (ADS)

We investigate into the rank-size distributions of urban agglomerations for India between 1981 to 2011. The incidence of a power law tail is prominent. A relevant question persists regarding the evolution of the power tail coefficient. We have developed a methodology to meaningfully track the power law coefficient over time, when a country experience population growth. A relevant dynamic law, Gibrat's law, is empirically tested in this connection. We argue that these empirical findings for India are in contrast with the findings in case of China, another country with population growth but monolithic political system.

Gangopadhyay, Kausik; Basu, Banasri

221

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

222

NOVEL BINDERS AND METHODS FOR AGGLOMERATION OF ORE  

SciTech Connect

Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not breakdown during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. Primary examples of this are copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process. As a result, operators of many facilities see large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching.

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

2005-04-01

223

Agglomeration characteristics of alumina sand-rice husk ash mixtures at elevated temperatures  

SciTech Connect

The agglomeration characteristics of alumina sand-rice husk ash mixtures were investigated at various levels of temperature (750, 850, 900, 950, and 1000 C) and ash content (0.0, 5.0, 0.0, 15.0, 20.0, and 25.0%) using light microscopy, scanning electron microscopy, and energy dispersive X-ray analysis techniques. The scanning electron microscopy and X-ray analysis were also used for the identification of the rick husk and elemental makeup of rice husk ash. There was no indication of melting at all the levels of temperature and ash content studied. However, weak and friable agglomerates were observed at 950 and 1000 C. The structure of the particles was not altered, and bonding by surface diffusion may be a possible mechanism for the formation of the weak, friable agglomerates. Physical entrapment by minute whiskers at the surface of rice husk ash may also be a factor. The use of alumina sand as an inert fluidizable material in fluidized bed systems will prevent the formation of these easily breakable structures because of particle friction caused by mixing and fluidization. Thus these friable structures are not expected to cause any problem during the normal operation of fluidized bed gasification systems that are normally operated at temperatures in the range of 700--800 C.

Mansaray, K.G.; Ghaly, A.E. [Technical Univ. of Nova Scotia, Halifax, Nova Scotia (Canada). Agricultural Engineering Dept.

1997-11-01

224

Isolation of palm oil-utilising, polyhydroxyalkanoate (PHA)-producing bacteria by an enrichment technique  

Microsoft Academic Search

In early attempts to isolate palm oil-utilising bacteria from palm oil mill effluent (POME), diluted liquid samples of POME were spread on agar containing POME as primary nutrient. 45 purified colonies were screened for intracellular lipids by staining with Sudan Black B. Of these, 10 isolates were positively stained. The latter were grown in a nitrogen-limiting medium with palm olein

Zazali Alias; Irene K. P. Tan

2005-01-01

225

Disposal systems and techniques for oil and hazardous chemicals recovered from marine spills. Final report  

Microsoft Academic Search

Existing and conceptual equipment systems are presented for transport and disposal of spill cleanup debris. Each system is categorized and discussed in terms of possible operational conditions, applicability to different types of oils and chemicals, and capacity for the solid debris constituent. Additional data include cost, dimensions and weights of key equipment elements, transportability, and crew requirements. For oil spills,

D. E. Ross; W. G. Hansen; J. G. Kuykendall; L. P. Erdberg

1979-01-01

226

Comparing classical and neural regression techniques in modeling crude oil viscosity  

Microsoft Academic Search

The importance of crude oil viscosity makes its accurate determination necessary for reservoir performance calculations, evaluation of hydrocarbon reserves, planning thermal methods of enhanced oil recovery, and designing production equipment and pipelines. Viscosity data are also involved in several dimensionless parameters to calculate flow regimes, friction factors and pressure gradients in multiphase flow problems. Numerous research efforts have been directed

A. M. Elsharkwy; R. B. C. Gharbi

2000-01-01

227

Thermogravimetric determination of vapor pressure of diffusion pump oils by Knudsen effusion cell technique  

Microsoft Academic Search

A procedure has been developed for the determination of vapor pressure of diffusion pump oils using a Knudsen effusion cell in conjunction with a vacuum balance. The extrapolated vapor pressure of the diffusion pump oils evaluated ranged from 4 x 10⁻⁸ to 2 x 10⁻⁶ torr at 20°C.

Steckel

1980-01-01

228

Physical and Chemical Analysis of Dielectric Properties and Differential Scanning Calorimetry Techniques on Buriti Oil  

Microsoft Academic Search

Dielectric constant (DC) analysis has been carried out on buriti oil (Mauritia flexuosa), in a scan temperature range of ?100–40°C. Fatty acid characterization was performed by gas crystallography and differential scanning calorimetry (DSC). Interesting physical characteristics were noted in a DC analysis on buriti oil. It revealed five different temperature anomalies, which were studied for the chemical properties of the

A. Garcia-Quiroz; S. G. C. Moreira; A. V. de Morais; A. S. Silva; G. N. da Rocha; P. Alcantara

2003-01-01

229

Differentiation of lemon essential oil based on volatile and non-volatile fractions with various analytical techniques: a metabolomic approach.  

PubMed

Due to the importance of citrus lemon oil for the industry, fast and reliable analytical methods that allow the authentication and/or classification of such oil, using the origin of production or extraction process, are necessary. To evaluate the potential of volatile and non-volatile fractions for classification purposes, volatile compounds of cold-pressed lemon oils were analyzed, using GC-FID/MS and FT-MIR, while the non-volatile residues were studied, using FT-MIR, (1)H-NMR and UHPLC-TOF-MS. 64 Lemon oil samples from Argentina, Spain and Italy were considered. Unsupervised and supervised multivariate analyses were sequentially performed on various data blocks obtained by the above techniques. Successful data treatments led to statistically significant models that discriminated and classified cold-pressed lemon oils according to their geographic origin, as well as their production processes. Studying the loadings allowed highlighting of important classes of discriminant variables that corresponded to putative or identified chemical functions and compounds. PMID:24054247

Mehl, Florence; Marti, Guillaume; Boccard, Julien; Debrus, Benjamin; Merle, Philippe; Delort, Estelle; Baroux, Lucie; Raymo, Vilfredo; Velazco, Maria Inés; Sommer, Horst; Wolfender, Jean-Luc; Rudaz, Serge

2013-08-03

230

Colloidal stability of coal-simulated suspensions in selective agglomeration  

SciTech Connect

A coal suspension was simulated by using graphite to simulate the carbonaceous fraction and kaolinite clay to simulate the ash fraction. Separate studies on each material established their response to additions of oxidized pyrite (ferrous sulfate) and a humic acid simulate (salicylic acid) in terms of zeta potentials profiles with pH and Ionic strength. Concentrations of iron and salicylic acid evaluated were 4.5 {times} 10{sup {minus}3} M and 2.0 {times} 10{sup {minus}4} M, respectively. The zeta potentials profiles of graphite, clay and hexadecane were negative throughout the pH ranges studied. The addition of iron lowered the zeta potentials all of the suspensions under all pH and ionic strength conditions. Salicylic acid decreased the graphite and hexadecane zeta potentials but had no effect on the clay zeta potential profiles. Agglomeration of graphite with bridging liquid shows distinct time dependent rate mechanisms, a initial growth of graphite agglomerates followed by consolidation phase. Graphite agglomeration was rapid with the maximum amount of agglomerate volume growth occurring in under 2-4 minutes. Agglomeration in the first two minutes was characterized by a 1st order rate mechanism. The presence of either Iron and salicylic acid generally improved the first order rates. The addition of clay also improved the first order rates except in the presence of salicylic acid. Heteroagglomeration of graphite with clay was found by hydrodynamic arguments to be unfavored. A multicomponent population balance model which had been developed for evaluating collision efficiencies of coal, ash and pyrite selective agglomeration was evaluated to explain these results. The growth and consolidation characteristics of graphite agglomeration for the experimental conditions examined herein revealed the limitations of such as model for this application.

Schurger, M.L.

1989-01-01

231

Novel Binders and Methods for Agglomeration of Ore  

SciTech Connect

Many metal extraction operations, such as leaching of copper, leaching of precious metals, and reduction of metal oxides to metal in high-temperature furnaces, require agglomeration of ore to ensure that reactive liquids or gases are evenly distributed throughout the ore being processed. Agglomeration of ore into coarse, porous masses achieves this even distribution of fluids by preventing fine particles from migrating and clogging the spaces and channels between the larger ore particles. Binders are critically necessary to produce agglomerates that will not break down during processing. However, for many important metal extraction processes there are no binders known that will work satisfactorily. Primary examples of this are copper heap leaching, where there are no binders that will work in the acidic environment encountered in this process, and advanced ironmaking processes, where binders must function satisfactorily over an extraordinarily large range of temperatures (from room temperature up to over 1200 C). As a result, operators of many facilities see a large loss of process efficiency due to their inability to take advantage of agglomeration. The large quantities of ore that must be handled in metal extraction processes also means that the binder must be inexpensive and useful at low dosages to be economical. The acid-resistant binders and agglomeration procedures developed in this project will also be adapted for use in improving the energy efficiency and performance of a broad range of mineral agglomeration applications, particularly heap leaching and advanced primary ironmaking. This project has identified several acid-resistant binders and agglomeration procedures that can be used for improving the energy efficiency of heap leaching, by preventing the ''ponding'' and ''channeling'' effects that currently cause reduced recovery and extended leaching cycle times. Methods have also been developed for iron ore processing which are intended to improve the performance of pellet binders, and have directly saved energy by increasing filtration rates of the pelletization feed by as much as 23%.

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

2006-12-31

232

Optical Properties of Some Silicone Diffusion-Pump Oils in the Vacuum Ultraviolet—Using an Open-Dish Technique  

Microsoft Academic Search

The optical properties of Dow Corning-704 and -705 diffusion-pump oils have been measured from 4?24.8 eV using an open-dish technique. These are the first liquids for which optical constants have been obtained above 11.8 eV. In the region above 10.6 eV, the real part of the dielectric constant is structureless. A collective oscillation involving ? and ? electrons is seen

G. D. Kerr; M. W. Williams; R. D. Birkhoff; L. R. Painter

1971-01-01

233

Microbiological techniques for paraffin reduction in producing oil wells: Final report  

SciTech Connect

Alpha Environmental has completed an eighteen month field oriented, cooperative research program with the US Department of Energy to demonstrate a new economically viable process using petroleum degrading microorganisms, a biocatalyst, formation water and inorganic nutrients to recover residual oil from reservoirs. Alpha's mixed community of microorganisms decomposes crude oil to produce detergents, CO/sub 2/, and new cells, thus mechanically and chemically releasing oil from reservoir pores. The naturally-occurring bacteria utilized in this project were previously selected by screening and isolating microorganisms from soils contaminated with crude oil and petroleum products. The activity and level of salt tolerance (to 20% salinity) of the bacteria is enhanced by a biocatalyst, previously developed by Alpha Environmental. Field evidence suggests that the biocatalyst provides catalytic oxygen to the microorganisms in the reservoir, which augments low levels of in-situ molecular oxygen. 25 refs., 10 figs., 6 tabs.

Oppenheimer, C.H.; Hiebert, F.K.

1989-04-01

234

Preparation of non-porous microspheres with high entrapment efficiency of proteins by a (water-in-oil)-in-oil emulsion technique.  

PubMed

Emulsification-solvent removal methods have been widely used for encapsulating bioactive macromolecules like proteins and polypeptides in biodegradable polymers. We report, a (water-in-oil)-in-oil emulsion technique wherein proteins and polypeptides differing in molecular weight and shape were encapsulated in polymers of current biomedical interest. When an oil was used as the processing medium in combination with a carefully selected mixed solvent system such that a stable (w/o1/o2 emulsion is formed and solvents are removed by a combination of extraction and evaporation, the entrapment efficiency was high and the product nonporous. The entrapment efficiency of globular proteins exceeded 90% while that of fibrous proteins was around 70%. Fracture studies revealed that the polymer matrix was dense. The mechanism of entrapment involved solvent-induced precipitation of the protein as the microspheres were being formed. The principle of the method will find use in preparation of non-porous polymer microparticles with reduced burst effect. PMID:10021485

Viswanathan, N B; Thomas, P A; Pandit, J K; Kulkarni, M G; Mashelkar, R A

1999-03-01

235

Budesonide nanoparticle agglomerates as dry powder aerosols with rapid dissolution.  

PubMed

Nanoparticle technology represents an attractive approach for formulating poorly water-soluble pulmonary medicines. Unfortunately, nanoparticle suspensions used in nebulizers or metered dose inhalers often suffer from physical instability in the form of uncontrolled agglomeration or Ostwald ripening. In addition, processing such suspensions into dry powders can yield broad particle size distributions. To address these encumbrances, a controlled nanoparticle flocculation process has been developed. Nanosuspensions of the poorly water-soluble drug budesonide were prepared by dissolving the drug in organic solvent containing surfactants followed by rapid solvent extraction in water. Different surfactants were employed to control the size and surface charge of the precipitated nanoparticles. Nanosuspensions were flocculated using leucine and lyophilized. Selected budesonide nanoparticle suspensions exhibited an average particle size ranging from approximately 160 to 230 nm, high yield and high drug content. Flocculated nanosuspensions produced micron-sized agglomerates. Freeze-drying the nanoparticle agglomerates yielded dry powders with desirable aerodynamic properties for inhalation therapy. In addition, the dissolution rates of dried nanoparticle agglomerate formulations were significantly faster than that of stock budesonide. The results of this study suggest that nanoparticle agglomerates possess the microstructure desired for lung deposition and the nanostructure to facilitate rapid dissolution of poorly water-soluble drugs. PMID:19130469

El-Gendy, Nashwa; Gorman, Eric M; Munson, Eric J; Berkland, Cory

2009-08-01

236

Advanced physical fine coal cleaning spherical agglomeration. Final report  

SciTech Connect

The project included process development, engineering, construction, and operation of a 1/3 tph proof-of-concept (POC) spherical agglomeration test module. The POC tests demonstrated that physical cleaning of ultrafine coal by agglomeration using heptane can achieve: (1) Pyritic sulfur reductions beyond that possible with conventional coal cleaning methods; (2) coal ash contents below those which can be obtained by conventional coal cleaning methods at comparable energy recoveries; (3) energy recoveries of 80 percent or greater measured against the raw coal energy content; (4) complete recovery of the heptane bridging liquid from the agglomerates; and (5) production of agglomerates with 3/8-inch size and less than 30 percent moisture. Test results met or exceeded all of the program objectives. Nominal 3/8-inch size agglomerates with less than 20 percent moisture were produced. The clean coal ash content varied between 1.5 to 5.5 percent by weight (dry basis) depending on feed coal type. Ash reductions of the run-of-mine (ROM) coal were 77 to 83 percent. ROM pyritic sulfur reductions varied from 86 to 90 percent for the three test coals, equating to total sulfur reductions of 47 to 72 percent.

Not Available

1990-09-01

237

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

238

Determination of peroxide value of edible oils by FTIR spectroscopy with the use of the spectral reconstitution technique.  

PubMed

Spectral reconstitution (SR), a technique that has been developed to facilitate mid-FTIR transmission analysis of inherently viscous samples, was applied to simplify and automate a previously reported FTIR method for the determination of peroxide value (PV) of edible oils. The basis of the PV determination is the rapid reaction of triphenylphosphine (TPP) with the hydroperoxides present in an oil to produce triphenylphosphine oxide (TPPO), which exhibits a readily measurable absorption band at 542 cm(-1). In the SR procedure, the viscosity of oil samples is reduced by mixing them with a diluent, which allows them to be readily loaded into a flow-through transmission cell. The spectra of the neat oil samples are then reconstituted from those of the diluted samples by using the absorption of a spectral marker present in the diluent to determine the dilution ratio. For the SR-based PV method, the TPP reagent was added to the diluent, which consisted of odorless mineral spirits (OMS) containing methylcyclopentadienyl manganese tricarbonyl (MMT) as the spectral marker. Sample preparation for PV analysis involved mixing approximately 10 ml of oil with approximately 25 ml of the TPP-containing diluent; accurate weighing or delivery of precise volumes was not required because the dilution ratio was determined spectroscopically from the intensity of the nu(CO) absorption of MMT at 1942 cm(-1) in the spectrum of the diluted sample relative to that in the spectrum of the diluent. Calibration standards, prepared by gravimetric addition of TPPO to a peroxide-free oil, were handled in the same manner, and a linear calibration equation relating the concentration of TPPO (expressed as the equivalent PV) to the absorbance of TPPO at 542 cm(-1) relative to a baseline at 530 cm(-1) in the reconstituted spectra was obtained, with a regression S.D. of +/-0.15 meq/kg oil. PV determinations on two sets of validation samples, spanning PV ranges of 0-20 and 0-2 meq/kg oil, were carried out in parallel by the AOCS titrimetric and SR-based FTIR procedures, and comparison of the results of duplicate analyses by the two methods indicated that the latter was more reproducible and slightly more sensitive. The SR-based PV method, when implemented on an autosampler-equipped FTIR system, allowed for the automated analysis of approximately 90 samples per hour. PMID:18371636

Yu, Xiuzhu; van de Voort, F R; Sedman, J

2007-06-13

239

Variation in the volatile oil composition of Eucalyptus citriodora produced by hydrodistillation and supercritical fluid extraction techniques.  

PubMed

This work reports variations in the yields and quality of volatiles produced from Eucalyptus citriodora leaves by different hydrodistillation (HD) and supercritical carbon dioxide extraction (SCE) techniques. HD techniques (1.5%) produced higher yields compared to SCE (0.7%). Citronellal, the major component, was maximum in the extract produced by SCE (79%) followed by oil produced by water-steam distillation (WSD) (72.6%) and water distillation (WD) (62.4%) techniques. Chemical composition of glycoside-bound volatiles produced by acid hydrolysis during HD was found to be very different from free volatiles, although in a minor quantity. The extent of artefact formation and release of aglycones was more profound in the bound volatile oil produced by WD than WSD. Highest oxygenated monoterpenes were found in SCE and WSD (93% each) followed by WD (91.4%). Although the SCE produced lower yields than the HD techniques, its extract is superior in quality in terms of higher concentration of citronellal. PMID:22559719

Mann, Tavleen S; Babu, G D Kiran; Guleria, Shailja; Singh, Bikram

2012-05-04

240

Ice slurry cooling research: Storage tank ice agglomeration and extraction  

SciTech Connect

A new facility has been built to conduct research and development on important issues related to implementing ice slurry cooling technology. Ongoing studies are generating important information on the factors that influence ice particle agglomeration in ice slurry storage tanks. The studies are also addressing the development of methods to minimize and monitor agglomeration and improve the efficiency and controllability of tank extraction of slurry for distribution to cooling loads. These engineering issues impede the utilization of the ice slurry cooling concept that has been under development by various groups.

Kasza, K. [Argonne National Lab., IL (United States); Hayashi, Kanetoshi [NKK Corp., Kawasaki (Japan)

1999-08-01

241

Agglomeration behavior of solid nickel on polycrystalline barium titanate  

SciTech Connect

This letter describes the phenomenon that takes place between nickel/barium titanate couples when heated under conditions employed in multilayer ceramic capacitor manufacturing practice: a 4hr, 1300°C isothermal anneal in 1% H2 – 99% N2. Dense, sputtered nickel films were observed to dewet the titanate and agglomerate into discrete or interconnected islands via a solid-state process. Up to a critical film thickness value of ~1.4?m, the degree of agglomeration was found to display an exponential dependence on the thickness of the original nickel film.

Weil, K. Scott; Mast, Eric S.; Sprenkle, Vince

2007-11-01

242

Continuous air agglomeration method for high carbon fly ash beneficiation  

DOEpatents

The carbon and mineral components of fly ash are effectively separated by a continuous air agglomeration method, resulting in a substantially carboree 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, McMahon L. (Pittsburgh, PA); Champagne, Kenneth J. (Monongahela, PA); Finseth, Dennis H. (Pittsburgh, PA)

2000-01-01

243

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

244

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

245

The use of thermal analysis techniques to obtain information relevant to the in-situ combustion process for enhanced oil recovery  

Microsoft Academic Search

Thein-situ combustion technique of enhanced oil recovery may be used for the recovery of heavy oil deposits. In order to predict when\\u000a this process may be used computer-based simulators are being developed. The data required by these simulators are currently\\u000a available from two sources: (i) combustion tubes; these are complex, expensive and time consuming to run; (ii) thermal analysis\\u000a techniques;

A. Millington; D. Price; R. Hughes

1993-01-01

246

Enantioselective Gas Chromatography: Analytical Technique for the Analysis of Mandarin Essential Oils  

Microsoft Academic Search

A simple and rapid method to determine the enantiomeric distribution of ?-pinene, ?-pinene, sabinene, limonene, linalool, terpinen-4-ol and ?-terpineol in mandarin essential oils has been determined. The method involves gas chromatographic analysis using a single oven, a couple of columns coated with modified cyclodextrins connected to a mechanical valves system and two FID detectors. The results are comparable to those

Vincenzo Zimbalatti

2006-01-01

247

Critical laboratory and field evaluation of selected surface prospecting techniques for locating oil and natural gas  

Microsoft Academic Search

The theoretical basis for the radiation HALO method in geochemical exploration for oil and gas is largely unproven but has been covered extensively in the literature. An evaluation of the method was conducted by direct field examination of some of the variables. The variables chosen were surface radiometry, magnetometry, gravity, and near-surface soil sampling. The radiometry included measurements of potassium-40,

R. J. Heemstra; R. M. Ray; T. C. Wesson; J. R. Abrams; G. A. Moore

1979-01-01

248

Agglomeration and Heap Leaching of Finely Ground Precious-Metal-Bearing Tailings.  

National Technical Information Service (NTIS)

The report presents information on the application of agglomeration technology to finely ground precious-metal-bearing tailings. Two commercial operations that have benefited from agglomeration technology are discussed. The technology is cost effective be...

G. E. McClelland D. L. Pool A. H. Hunt J. A. Eisele

1985-01-01

249

Radiation-Induced Particulate Agglomeration Feasibility Study.  

National Technical Information Service (NTIS)

The removal of aerosol particles from a gas by standard gas filtration techniques is more difficult for submicron particles than for larger particles. Filtration methods presently in use can achieve high efficiencies of submicron particle removal by use o...

B. Sellers F. A. Hanser L. W. Parker

1978-01-01

250

Effect of acceleration on agglomeration of aluminum particles during combustion of composite solid propellants  

Microsoft Academic Search

The effect of the normal acceleration (g-load) on formation of agglomerates and their distribution function is examined within the framework of the statistical model\\u000a of aluminum agglomeration. A parametric study of aluminum agglomeration with different values of normal g-loads is performed. The theory developed predicts a new effect, namely, a nonmonotonic dependence of the mean-mass size of\\u000a agglomerates leaving the

S. A. Rashkovskii

2007-01-01

251

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

252

The degree and kind of agglomeration affect carbon nanotube cytotoxicity  

Microsoft Academic Search

The urgent need for toxicological studies on carbon nanotubes (CNTs) has arisen from the rapidly emerging applications of CNTs well beyond material science and engineering. In order to provide a basis for comparison to existing epidemiological data, we have investigated CNTs at various degrees of agglomeration using an in vitro cytotoxicity study with human MSTO-211H cells. Non-cytotoxic polyoxyethylene sorbitan monooleate

Peter Wick; Pius Manser; Ludwig K. Limbach; Ursula Dettlaff-Weglikowska; Frank Krumeich; Siegmar Roth; Wendelin J. Stark; Arie Bruinink

2007-01-01

253

Spherical agglomeration during crystallization of an active pharmaceutical ingredient  

Microsoft Academic Search

Lobenzarit disodium (LBD) salt is a drug used in the treatment of rheumatoid arthritis diseases. The objective of this work is to propose and validate a method for selecting the best wetting agent allowing to obtain spherical agglomerates during crystallization. This method is based on the so-called Washburn's test (capillary rise of liquids in a granular medium). Crystallization tests carried

Daniel Amaro-González; Béatrice Biscans

2002-01-01

254

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

255

Alternating electric field induced agglomeration of carbon black filled resins  

Microsoft Academic Search

This letter reports on our observation that an alternating electric field is able to induce the formation of an electrically conducting network in carbon black (CB) filled resins well below the zero-field percolation threshold. Compared with the recently presented dc method, the ac agglomeration is more efficient in two respects: it proceeds significantly faster under equivalent conditions and is still

Matthias-Klaus Schwarz; Wolfgang Bauhofer; Karl Schulte

2002-01-01

256

Turbulence induced by an acoustic field - Application to acoustic agglomeration  

Microsoft Academic Search

The efficiency of sonic coagulation and precipitation of particles in an acoustic field is strongly reinforced, above the acoustic intensity corresponding to the enhancement of acoustic turbulence. The aim of this work is to evaluate the turbulence properties of the experimental system in order to calculate the acoustic agglomeration kernels and precipitation rates. The knowledge of the aerodynamic behavior of

Claire Malherbe; Denis Boulaud; Alain Boutier; Jean Lefevre

1988-01-01

257

Informality and agglomeration economies: in search of the missing links  

Microsoft Academic Search

The informal sector absorbs on average 50% of employment in developing countries. However, it has not been considered in New Economic Geography (NEG) models that try to explain urbanization and agglomeration in developing countries. In a first attempt to bridge this gap, we develop a NEG model that incorporates the informal sector. Empirical evidence shows that the informal sector is

Ana Isabel Moreno Monroy; Michiel Gerritse

2011-01-01

258

Effect of oxygen agglomeration in polycrystalline Si (SIPOS) films  

Microsoft Academic Search

IR transmission spectra of SIPOS structures were measured and were investigated by using an approach of deconvolution of the Si–O stretching band into Gauss profiles. It was found that the space distribution of oxygen in SIPOS layers treated at elevated temperatures does not correspond to the prediction of RBM statistics. The oxygen agglomeration was observed. Optical microscopy was also applied

I. P. Lisovskyy; V. G. Litovchenko; B. M. Gnenyy; W. Fussel; A. E. Kiv; V. N. Soloviev; T. I. Maximova

2002-01-01

259

Multinationals' location choice, agglomeration economies and public incentives  

Microsoft Academic Search

We study the regional location of multidimensionals in Ireland since the 1970s by focusing on the role played by agglomeration economies and public incentives intent on dispersing industrial activity to the more disadvantaged areas of Ireland. We find that regional policy has only been effective in attracting low-tech firms to the disadvantaged areas during the time when there was a

Salvador BARRIOS; Holger GORG; Eric STROBL

2003-01-01

260

Agglomeration and the Geography of Localization Economies in Canada  

Microsoft Academic Search

Baldwin J. R., Beckstead D., Brown W. M. and Rigby D. L. Agglomeration and the geography of localization economies in Canada, Regional Studies.?This paper maps the spatial variation in productivity levels across Canadian cities and models the underlying determinants of that variation. There are two main goals. The first is to confirm the existence, the nature and the size of

John R. Baldwin; Desmond Beckstead; W. Mark Brown; David L. Rigby

2008-01-01

261

Experimental study and modeling of fluidized bed coating and agglomeration  

Microsoft Academic Search

This work deals with the fluidized bed coating and agglomeration of solid particles. The effect of particle size on coating criteria was investigated using sand particles as the coating support and aqueous solutions containing NaCl as coating liquid. The results showed that both growth rate and efficiency increase with decreasing the particle size. The growth was mainly governed by layering

K. Saleh; D. Steinmetz; M. Hemati

2003-01-01

262

CONSOLIDATION OF K BASIN SLUDGE DATA AND EXPERIENCES ON AGGLOMERATE FORMATION  

Microsoft Academic Search

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

2010-01-01

263

Revisiting Marshall's Agglomeration Economies: Technological Relatedness and the Evolution of the Sheffield Metals Cluster  

Microsoft Academic Search

Potter A. and Watts H. D. Revisiting Marshall's agglomeration economies: technological relatedness and the evolution of the Sheffield metals cluster, Regional Studies. According to Alfred Marshall, firms receive increasing returns from a trinity of agglomeration economies: a local pool of skilled labour, local supplier linkages and local knowledge spillovers. This article re-examines the mechanisms underlying Marshall's agglomeration economies in the

Antony Potter; H. Doug Watts

2012-01-01

264

Hedonic and utilitarian shopper types in evolved and created retail agglomerations  

Microsoft Academic Search

This paper focuses on the impact of hedonic and utilitarian values of shopping on retail agglomeration patronage issues, in particular on shopping behaviour and the perception of retail agglomerations. Our empirical study is based on a discussion of agglomerations' potential to attract utilitarian and hedonic shopper types. A sample of 2,139 customers were interviewed in a peripheral shopping mall as

Christoph Teller; Thomas Reutterer; Peter Schnedlitz

2008-01-01

265

Simulation of acoustic agglomeration processes of poly-disperse solid particles  

Microsoft Academic Search

This article presents the simulation of acoustic agglomeration of poly-disperse solid particles with the direct simulation Monte Carlo method. The modelled processes include the agglomeration due to the orthokinetic and hydrodynamic mechanisms, Brownian coagulation and wall deposition. The aggregates formed during the agglomeration process were characterised as mass fractal aggregates with an equivalent radius to estimate the average radius of

Changdong Sheng; Xianglin Shen

2007-01-01

266

Combustion characteristics of lignite and oil shale samples by thermal analysis techniques  

Microsoft Academic Search

In this research thermal analysis and kinetics of ten lignite's and two oil shale samples of different origin were performed\\u000a using a TA 2960 thermal analysis system with thermogravimetry (TG\\/DTG) and differential al analysis (DTA) modules. Experiments\\u000a were performed with a sample size of ~10 mg, heating rate of 10C min-1. Flow rate was kept constant (10 L h-1) in

M. V. Kök; G. Pokol; C. Keskin; J. Madarász; S. Bagci

2004-01-01

267

Comparison of Modern Extraction Techniques in Analysis of Soil Contaminated with Fuel and Crude Oil Spills  

Microsoft Academic Search

Supercritical fluid extraction (SFE) with CO2 and pressurised fluid extraction (PFE) have been investigated for assays of soil samples contaminated with crude oil and compared with reference Soxhlet extractions using 1,1,2?trichlorotrifluoroethane (Ledon 113). Quantitative extraction of total petroleum hydrocarbons (TPH) by SFE was accomplished in 30 min at a pressure of 40 MPa and temperature of 100°C by using pure CO2. For

Karel Ventura; Martin Adam; Jaromír Dostálek

2003-01-01

268

Color graphics and computer mapping techniques applied to reappraisal of a mature oil field  

SciTech Connect

Reappraisal of mature oil fields for new drilling and development requires gathering and understanding large amounts of geologic data. Although translating this information into computer databases is usually a tedious effort at the front end of a project, this time will be justified near the end of the project by computational versatility and increased graphical display capabilities. If properly applied, color graphics can be very valuable in the decision-making process. As an example, the Zenith field in central Kansas, which covers 16 mi{sup 2} with wells at 10- to 40-acre spacings, is illustrated using a series of color maps displaying geologic and well data. Color maps with various shades of a given color provide attractive and readily understandable display of isopach, porosity, and porosity-feet information. Data regarding individual wells are effectively presented by placing at mapped well locations color-coded symbols that depict completion dates, abandonment dates, and years producing. Size and color differentiation of these symbols aid in identifying pay zones producing at each well, production potentials, gas-oil ratios, and water-oil ratios. Volumetric information, such as remaining oil in place and associated water saturations, are displayed on maps as colored patches that correspond to specific geographic areas. Computer-generated cross sections constructed from well formation tops also aid in illustrating geologic relationships that may not be readily evident. Color graphics like those listed above helped quickly convey information to geologists and engineers. In turn, decisions were made of where the field would further develop.

Wong, Janchung (Kansas Geological Survey, Lawrence (United States)); Newell, K.D. (Univ. of Kansas, Lawrence (United States))

1991-08-01

269

Particle engineering of benzoic acid by spherical agglomeration.  

PubMed

The influence of process conditions on the properties of benzoic acid spherical agglomerates, are investigated. Agglomerates are produced in a fed-batch agitated tank process. Benzoic acid is dissolved in ethanol and the solution is mixed with the bridging liquid, before being fed into an agitated aqueous solution. A broader investigation has been performed using heptane as the bridging liquid, and in further experiments different bridging liquids are compared. The results show that the bridging liquid has an influence on the product properties, with diethyl ether and ethyl acetate being at the extreme end with no agglomerates formed at all. Using any of the other five solvents (chloroform, toluene, heptane, pentane, or cyclohexane) spherical agglomerates are formed, as long as a sufficient amount of the bridging liquid is used. The results show that the particle size and strength increase with increasing amount of bridging liquid, and with decreasing temperature. At amount of bridging liquid producing optimum particle shape, the largest agglomerates are produced when using either cyclohexane operating at 5 °C, or using toluene in a process at 20 °C. The highest particle fracture stress is obtained using toluene as the bridging liquid regardless of temperature. The particle shape depends on the bridging liquid, and becomes completely spherical when toluene or pentane is used. For four of the solvents the particle morphology improves with decreasing temperature, but for cyclohexane the result is the opposite. By continued agitation beyond the completion of the feeding, particle size and strength gradually increases and also the shape gradually becomes more spherical. High compressibility and low elastic recovery suggest that the particles are favorable for direct tabletting. The results are analyzed and discussed against capillary theory and granulation mechanisms. PMID:22266212

Thati, Jyothi; Rasmuson, Åke C

2012-01-15

270

Oil field development techniques: Proceedings of the Daqing international meeting, 1982  

Microsoft Academic Search

The petroleum geologist historically has focused on exploration techniques, leaving post-discovery development work in the hands of petroleum engineers. Today, however, the scenario is changing as geologists become more and more involved in development strategies due to their expertise in key concepts and techniques. Geologists' understanding of seismic stratigraphy, log studies, and pressure measurements, which give a picture of reservoir

J. F. Mason; P. A. Dickey

1989-01-01

271

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

272

Development of Impregnated Agglomerate Pelletization (IAP) process for fabrication of (Th,U)O2 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)O2 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, ThO2 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)O2 pellets. In this study, fabrication of (Th,U)O2 mixed oxide pellets containing 3-5 wt.% UO2 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

273

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

274

Using geochemical techniques to identify salinity sources in the freshwater Navajo aquifer, Aneth Oil Field, Utah  

SciTech Connect

The salinity of water in the Triassic and Jurassic Navajo Sandstone in southeastern Utah has increased locally since 1952. The Navajo aquifer, within the Navajo Sandstone, is major source of water for domestic use and livestock in the area. From 1989 to 1991, concentration of dissolved solids in one well increased by as much as 5500 mg/L. The source or sources of the saline water and the reasons for the local increases are not known; however, mixing with either oil-field brines (OFB) or non-oil-field brines (NOFB) from the Pennsylvanian Paradox Formation could possibly cause the increase salinity. One of the objectives of an ongoing study is to use end-member mixing models and step-wise discriminant analysis to determine the possible source or sources of saline water causing the observed increase in salinity in the Navajo aquifer. Discriminant analysis was used on the major-ion/chloride ratios to identify saline-water sources that could have mixed with Navajo aquifer water.

Nafiz, D.L.; Spangler, L.E. (Geological Survey, Salt Lake City, UT (United States))

1993-08-01

275

Characterization of Lippia sidoides oil extract-b-cyclodextrin complexes using combined thermoanalytical techniques  

Microsoft Academic Search

Thermoanalytical techniques, being rapid and un-expensive have been used for the investigation of the cyclodextrin inclusion\\u000a complexes for three decades. The conventional thermoanalytical techniques (TG and DTA\\/DSC) follow the thermal properties of\\u000a the uncomplexed compounds. Consequently, the inclusion complex formation as well as the liberation of the entrapped guest\\u000a cannot be followed. Monitoring the products of the thermal fragmentation of

L. P. Fernandes; Zs. Éhen; T. F. Moura; Cs. Novák; J. Sztatisz

2004-01-01

276

Novel Simulation Techniques Used in a Gas Reservoir With a Thin Oil Zone: Troll Field  

Microsoft Academic Search

Choice of production strategy in modern reservoir management relies heavily on numerical simulation. Large fields may require prohibitively large computer times. This paper reports on new techniques developed to save computer and engineering time: local grid refinement with small timesteps and flux boundary conditions for simulating regions of special interest. The combined use of these techniques allowed flexible, non-time-consuming, user-friendly

Adolfo Henriquez; Odd Apeland; Oystein Lie; Ian Cheshire

1992-01-01

277

Novel simulation techniques used in a gas reservoir with a thin oil zone; Troll field  

SciTech Connect

Choice of production strategy in modern reservoir management relies heavily on numerical simulation. Large fields may require prohibitively large computer times. This paper reports on new techniques developed to save computer and engineering time: local grid refinement with small timesteps and flux boundary conditions for simulating regions of special interest. The combined use of these techniques allowed flexible, non-time-consuming, user-friendly reservoir simulation of a variety of reservoir management scenarios for Troll field.

Henriquez, A.; Apeland, O.J.; Lie, O. (Statoil (Norway)); Cheshire, I. (Intera Petroleum Production Services (United Kingdom))

1992-11-01

278

Cracking kinetics of crude oil and alkanes determined by diamond anvil cell-fluorescence spectroscopy pyrolysis: technique development and preliminary results  

Microsoft Academic Search

Non-conventional diamond anvil cell (DAC) pyrolysis techniques have been developed to monitor in situ the cracking of oils and hydrocarbon compounds using fluorescence spectroscopy (FS). The experiments were conducted under closed-system conditions at five programmed heating rates up to a maximum temperature of 650°C. The fluorescence of oil reveals two major stages of intensity change during cracking pyrolysis. This appears

Wuu-Liang Huang; G. A. Otten

2001-01-01

279

Reaction kinetics and physical mechanisms of ash agglomeration. Progress report, August 24-November 23, 1984  

SciTech Connect

The work performed on the research program, ''Reaction Kinetics and Physical Mechanisms of Ash Agglomeration,'' is described. This program consists of four tasks: (1) Test Plan Development, (2) Effect of Mineral Type and Distribution on Ash Behavior, (3) Rates of Mineral Matter Interaction in the Gasifier Oxidation Zone, and (4) Ash Particle Dynamics Studies. The research program addresses the key issues of ash particle contact, conditions and rates of reaction of mineral matter, and agglomeration conditions in fluidized-bed gasification. In particular, the objectives of the investigation are: to determine the effect of coal mineral matter variation on the behavior of ash and to correlate this behavior to a detailed petrographic analysis of the mineral matter present in the coal; to determine the reaction rates of individual clays and silica with the pyrite and carbonates of coal as a function of temperature, pressure, and gas composition; and to determine the feasibility of employing the dielectrophoretic manipulation technique to identify the conditions under which colliding ash particles coalesce, shatter, or deposit. The test plan for Task 1 was completed and was approved by the Department of Energy. Also, selection of the coals to be tested in the study of the effect of mineral matter type and distribution on ash behavior was begun.

Carty, R.H.; Mason, D.M.; Babu, S.P.

1985-01-01

280

Preventing ash agglomeration during gasification of high-sodium lignite  

SciTech Connect

Various additives were evaluated to assess their ability to prevent ash agglomeration during the gasification of high-sodium lignite. Additives that showed promise in simple muffle furnace tests included meta-kaolin, vermiculite, two types of silica fume, and one type of bauxite. Additives that were tested and rejected included dolomite, calcite, sand flour, kaolinite, fine kaolin, and calcined bauxite. Based on the muffle furnace test results, the meta-kaolin was selected for a follow-on demonstration in a pilot-scale coal gasifier. Pilot-scale testing showed that the addition of coarse (minus 14-mesh, 920-{mu}m mean size) meta-kaolin at a feed rate roughly equivalent to the ash content of the lignite (10 wt %) successfully prevented agglomeration and deposition problems during gasification of high-sodium lignite at a maximum operating temperature of 927{sup o}C (1700{sup o}F). 13 refs., 24 figs., 1 tab.

Robert S. Dahlin; Johnny R. Dorminey; WanWang Peng; Roxann F. Leonard; Pannalal Vimalchand [Southern Research Institute and Southern Company Services, Wilsonville, AL (USA). Power Systems Development Facility

2009-01-15

281

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

282

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

283

The process of suburbanization in the agglomeration of Budapest  

Microsoft Academic Search

One of the major developments in post-socialist cities is the increasing outflow of people from the city to the surrounding\\u000a settlements. Budapest is a case in point. The agglomeration used to receive migrants coming to live and work in the capital\\u000a (i.e., rural urbanization). After the political and economic changes of the 1980s and 1990s, the suburban area around Budapest

Herman Kok; Zoltán Kovács

1999-01-01

284

Labor migration, human capital agglomeration and regional development in China  

Microsoft Academic Search

We estimate a skill-based directional migration model to assess the effects of regional human capital agglomeration on labor migration in China. Upon accounting for regional differentials in skill-based compensation, cost-of-living, amenities, and the like, model estimates indicate the importance of destination human capital concentration to high-skill migrants. In marked contrast, low-skill migrants are found to have little incentive to co-locate

Yuming Fu; Stuart A. Gabriel

2012-01-01

285

Use of fly ash agglomerates for removal of arsenic  

Microsoft Academic Search

The aim of this work is to investigate the application of fly ash adsorbent for removal of arsenite ions from dilute solution\\u000a (100–1,000 ppm). Experiments were carried out using material from the “Turów” (Poland) brown-coal-burning power plant, which\\u000a was wetted, then mixed and tumbled in a granulator to form spherical agglomerates. Measurements of arsenic adsorption from\\u000a aqueous solution were carried out

Izabela Polowczyk; Anna Bastrzyk; Tomasz Ko?lecki; Wojciech Sawi?ski; Piotr Rudnicki; Adam Soko?owski; Zygmunt Sadowski

2010-01-01

286

Oil field development techniques: Proceedings of the Daqing international meeting, 1982  

SciTech Connect

The petroleum geologist historically has focused on exploration techniques, leaving post-discovery development work in the hands of petroleum engineers. Today, however, the scenario is changing as geologists become more and more involved in development strategies due to their expertise in key concepts and techniques. Geologists' understanding of seismic stratigraphy, log studies, and pressure measurements, which give a picture of reservoir size and character; of reservoir modeling; and of depositional environment identification, which is used to design secondary and enhanced recovery, is being directly applied to reservoir development strategies.

Mason, J.F.; Dickey, P.A.

1989-01-01

287

Nifedipine Nanoparticle Agglomeration as a Dry Powder Aerosol Formulation Strategy  

PubMed Central

Efficient administration of drugs represents a leading challenge in pulmonary medicine. Dry powder aerosols are of great interest compared to traditional aerosolized liquid formulations in that they may offer improved stability, ease of administration, and simple device design. Particles 1–5 µm in size typically facilitate lung deposition. Nanoparticles may be exhaled as a result of their small size; however, they are desired to enhance the dissolution rate of poorly soluble drugs. Nanoparticles of the hypertension drug nifedipine were co-precipitated with stearic acid to form a colloid exhibiting negative surface charge. Nifedipine nanoparticle colloids were destabilized by using sodium chloride to disrupt the electrostatic repulsion between particles as a means to achieve the agglomerated nanoparticles of a controlled size. The aerodynamic performance of agglomerated nanoparticles was determined by cascade impaction. The powders were found to be well suited for pulmonary delivery. In addition, nanoparticle agglomerates revealed enhanced dissolution of the drug species suggesting the value of this formulation approach for poorly water soluble pulmonary medicines. Ultimately, nifedipine powders are envisioned as an approach to treat pulmonary hypertension.

Plumley, Carl; Gorman, Eric M.; Munson, Eric J.; Berkland, Cory

2009-01-01

288

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

2011-01-07

289

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 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.

Chidsey, T.C. Jr.; Lorenz, D.M.; Culham, W.E.

1997-10-15

290

Ignition, combustion, and agglomeration of encapsulated aluminum particles in a composite solid propellant. II. Experimental studies of agglomeration  

Microsoft Academic Search

The combustion characteristics of propellants containing AP, HMX, an energetic binder, and aluminum particles with various\\u000a polymer coatings are studied at pressures of 0.15 and 4.6 MPa. It is found that the coatings influence the burning rate, the\\u000a particle size distribution of condensed combustion products, and the completeness of aluminum combustion. It is shown that\\u000a the agglomeration can be reduced

O. G. Glotov; D. A. Yagodnikov; V. S. Vorob’ev; V. E. Zarko; V. N. Simonenko

2007-01-01

291

Mechanisms of mineral scaling in oil and geothermal wells studied in laboratory experiments by nuclear techniques  

NASA Astrophysics Data System (ADS)

Two independent nuclear methods have been developed and tested for studies of mineral scaling mechanisms and kinetics related to the oil and geothermal industry. The first is a gamma transmission method to measure mass increase with a 30 MBq source of 133Ba. The other method applies radioactive tracers of one or more of the scaling components. CaCO3-precipitation has been used as an example here where the main tracer has been 47Ca2+. While the transmission method is an indirect method, the latter is a direct method where the reactions of specific components may be studied. Both methods are on-line, continuous and non-destructive, and capable to study scaling of liquids with saturation ratios approaching the solubility product. A lower limit for detection of CaCO3 with the transmission method in sand-packed columns with otherwise reasonable experimental parameters is estimated to be <1 mg in a 1 cm section of the tube packed with silica sand while the lower limit of detection for the tracer method with reasonable experimental parameters is estimated to <1 µg in the same tube section.

Bjørnstad, T.; Stamatakis, E.

2006-01-01

292

Improved techniques for fluid diversion in oil recovery. First annual report  

SciTech Connect

This three-year project has two general objectives. The first objective is to compare the effectiveness of gels in fluid diversion with those of other types of processes. Several different types of fluid-diversion processes are being compared, including those using gels, foams, emulsions, and particulates. The ultimate goals of these comparisons are 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 are being performed to verify which materials are the most effective in entering and blocking high-permeability zones. Another objective of the project is to identify the mechanisms by which materials (particularly gels) selectively reduce permeability to water more than to oil. This report describes work performed during the first year of the project. Following the introduction, Chapters 2 through 5 present several surveys concerning field applications of gel treatments. Based on the results of the surveys, guidelines are proposed in Chapter 5 for the selection of candidates for gel treatments (both injection wells and production wells). Chapters 6, 7, 8, and 11 discuss theoretical work that was performed during the project. Chapter 6 examines whether Hall plots indicated selectivity during gelant placement. Chapter 7 discusses several important theoretical aspects of gel treatments in production wells with water-coning problems. Chapter 8 considers exploitation of density differences during gelant placement. Chapter 11 presents a preliminary consideration of the use of precipitates as blocking agents. Chapters 9 and 10 detail the experimental work for the project. Chapter 9 describes an experimental investigation of gelant placement in fractured systems. Chapter 10 describes experiments that probe the mechanisms for disproportionate permeability reduction by gels.

Seright, R.S.

1993-12-01

293

Effect of temperature on carbon-black agglomeration in hydrocarbon liquid with adsorbed dispersant.  

PubMed

Suspensions of carbon black in oil, stabilized with adsorbed polyisobutylene succinimide (PIBSI) dispersant, are commonly used as model systems for investigating the soot-handling characteristics of motor oils. The structure of the carbon-black agglomerates changes dramatically with temperature; this results in a concomitant change in the suspension rheology. Linear and nonlinear rheological experiments indicate a large increase of the interparticle attractions as the temperature is raised. To elucidate the origin of this behavior, we investigate the effect of temperature on the stabilizing effect of the dispersant. Measurements of adsorption isotherms of the dispersant on carbon black indicate that there is little variation of the binding energy with temperature. Intrinsic viscosity measurements of PIBSI dispersants in solution clearly exhibit an inverse dependence of the dispersant chain dimension with temperature. These results suggest that the temperature-dependent changes in the chain conformation of the PIBSI dispersant are primarily responsible for the changes in the dispersion rheology, and we propose a simple model to account for these data. PMID:15667169

Won, You-Yeon; Meeker, Steve P; Trappe, Veronique; Weitz, David A; Diggs, Nancy Z; Emert, Jacob I

2005-02-01

294

Combustion of CWF agglomerates from pulverized or micronized bituminous coal, carbon black, and diesel soot  

SciTech Connect

Fundamental studies were conducted to explore the role of coal grind size on the combustion characteristics of coal-water fuel (CWF) agglomerates. The agglomerates were prepared from bituminous coals of two different grind sizes: (40 [mu]m, and 4[mu]m) mean size as well as blends thereof. Additional experiments were performed with predried agglomerates from water slurries of carbon black or diesel soot. All agglomerates were in the size range of 150--900 [mu]m and were either plain or impregnated with calcium magnesium acetate (CMA). Upon heating and devolatilization, the bituminous coal agglomerates studied were found to melt, mildly swell, and form cenospheric structures. Individual pulverized coal particles also form small cenospheres themselves, superimposed on large agglomerate-derived cenospheres. Combustion of CWF agglomerates, in the size range examined, occurred with distinct volatile and char combustion phases with the latter burning in a diffusion-controlled mode. The combustion behavior of pulverized and micronized coal agglomerates of the same size was strikingly similar. The presence of dissolved CMA accelerated setting of the slurries and, upon water evaporation it suppressed melting and cenospheres formation of the coal particles and agglomerates alike. Also, CMA mildly influence the agglomerate combustion behavior, causing both larger volatile flames and char temperatures that peaked at the first half of the burnout period and decreased thereafter, but did not substantially affect the char burnout time. Carbon black and diesel soot agglomerates did not form cenospheres and the latter burned a little hotter and faster but, basically, their combustion was similar to that of CWF chars. Bulk fragmentation was consistently observed only in the case of CMA-impregnated carbon black agglomerates.

Atal, A.; Levendis, Y.A. (Northeastern Univ., Boston, MA (United States). Dept. of Mechanical Engineering)

1994-09-01

295

Agglomeration and strength development of deposits in CFBC boilers firing high-sulfur fuels  

Microsoft Academic Search

Fluidized bed combustor (FBC) ashes from high-sulfur, low-ash fuels, can agglomerate if subjected to sulfating conditions for long enough (days to weeks). The degree of sulphation increases with both temperature and time under these conditions, and at a conversion equivalent to the production of 50–60% or more of CaSO4 in the deposit the ashes agglomerate. Fly ash agglomerates less readily

E. J Anthony; L Jia

2000-01-01

296

Agglomeration economies and location choice of Korean manufacturers within the United States  

Microsoft Academic Search

Employing the micro data for 1997–2004, we investigate the location decision of Korean-affiliated manufacturing investments in the United States. The conditional logit estimates confirm that although industry-specific Korean agglomeration and domestic agglomeration play an important role, the Foreign Direct Investment (FDI) location is more sensitively affected by the interstate difference in endowment conditions than by the same nationality agglomeration. Both

Ki-Dong Lee; Seok-Joon Hwang; Min-hwan Lee

2011-01-01

297

Agglomeration economies and location choice of Korean manufacturers within the United States  

Microsoft Academic Search

Employing the micro data for 1997–2004, we investigate the location decision of Korean-affiliated manufacturing investments in the United States. The conditional logit estimates confirm that although industry-specific Korean agglomeration and domestic agglomeration play an important role, the Foreign Direct Investment (FDI) location is more sensitively affected by the interstate difference in endowment conditions than by the same nationality agglomeration. Both

Ki-Dong Lee; Seok-Joon Hwang; Min-hwan Lee

2012-01-01

298

Laser desorption/ionization techniques in the characterization of high molecular weight oil fractions. Part 1: asphaltenes.  

PubMed

The molecular weight distribution of the asphaltene fractions of two types of crude oils from two different Italian fields (samples 1 and 2) was investigated. The analytical tools used to perform these analyses were matrix assisted laser desorption ionization (MALDI) and laser desorption ionization (LDI) mass spectrometry. After observing that the use of the matrix (as well as the addition of Ag+) did not improve the quality of the data compared to that obtained in LDI conditions, all further measurements were performed with the latter technique. Operating under usual conditions of laser power and delay time, a very low resolution was observed, showing only macroscopic differences between the two samples in the molecular weight distribution of the different components. An accurate study on the possible reasons of this undesirable behavior indicates that it can originate from space charge phenomena occurring either in the ion source region or during the flight. A valid parameterization of the delay time and the laser power allowed higher quality spectra to be obtained. Surface-enhanced laser desorption ionization (SELDI) measurements were also performed using normal phase (silica) as the sample holder surface. Under these conditions, better results are obtained, proving that the sample-surface interaction is important to achieve, by means of laser irradiation, a homogeneous set of product ions. Both asphaltene samples were fractionated in five subfractions by gel-permeation chromatography (GPC) to obtain a better separation of the molecular weight distributions; the related spectra confirmed these findings. By using different approaches, relevant and reproducible differences between the asphaltene fractions of the two oil samples were observed. PMID:16941524

Rizzi, Andrea; Cosmina, Paola; Flego, Cristina; Montanari, Luciano; Seraglia, Roberta; Traldi, Pietro

2006-09-01

299

Project risk management using multiple criteria decision-making technique and decision tree analysis: a case study of Indian oil refinery  

Microsoft Academic Search

This study proposes an integrated analytical framework for effective management of project risks using combined multiple criteria decision-making technique and decision tree analysis. First, a conceptual risk management model was developed through thorough literature review. The model was then applied through action research on a petroleum oil refinery construction project in the Central part of India in order to demonstrate

Prasanta Kumar Dey

2011-01-01

300

Pharmacokinetics evaluation of soft agglomerates for prompt delivery of enteric pantoprazole-loaded microparticles.  

PubMed

Soft agglomerates containing pantoprazole-loaded microparticles were developed with the aim of prompt delivery of gastro-resistant particles. The objective was to evaluate the relative bioavailability in dogs after the oral administration of soft agglomerates. Gastro-resistant pantoprazole-loaded microparticles prepared by spray drying were mixed with mannitol/lecithin spray-dried powder and agglomerated by vibration. One single oral dose (40mg) was administered to dogs. Each dog received either a reference tablet or hard gelatin capsules containing the agglomerates. The plasma profiles were evaluated by non-compartmental and compartmental approaches, and the pharmacokinetic parameters were determined. The agglomerates presented 100% of drug particle loading and a production yield of 80.5%. The amount of drug absorbed after oral dosing was similar after reference or agglomerate administration, leading to a relative bioavailability of 108%. The absorption lag-time was significantly reduced after agglomerate administration (from 135.5+/-50.6 to 15.0+/-2.5min). The agglomerated gastro-resistant pantoprazole-loaded microparticles reduced time to peak plasma. The agglomerates were equivalent to the reference tablets in terms of extent but not in terms of rate of absorption, showing that this formulation is an alternative to single-unit oral dosing with enteric coating and with the advantage of reducing time to effect. PMID:19969078

Raffin, Renata P; Colomé, Letícia M; Hoffmeister, Cristiane R D; Colombo, Paolo; Rossi, Alessandra; Sonvico, Fabio; Colomé, Lucas M; Natalini, Claudio C; Pohlmann, Adriana R; Costa, Teresa Dalla; Guterres, Silvia S

2009-12-05

301

Numerical derivation of forces on particles and agglomerates in a resonant acoustic field  

NASA Astrophysics Data System (ADS)

Particles and agglomerates are investigated in gaseous acoustic flow fields. Acoustic fields exert forces on solid objects, which can influence the shape of the exposed bodies, even to the point of breakage of the structures. Motivated by experimentally observed breakage of agglomerates in an acoustic levitator (f = 20 kHz), a numerical study is presented that derives the acoustic forces on a complex model agglomerate from the pressure and velocity fields of a resonant standing ultrasound wave, calculated by computational fluid dynamics (CFD). It is distinguished between the drag and lift/lateral forces on the overall agglomerate and on the different primary particles of the model.

Knoop, Claas; Fritsching, Udo

2013-10-01

302

Mechanistic studies of nanocluster nucleation, growth, and agglomeration  

NASA Astrophysics Data System (ADS)

Following a critical review of the relevant literature, the research presented herein focuses on the mechanisms by which transition-metal nanoclusters nucleate, grow, and agglomerate. The studies include: (i) the generality of the recently uncovered, 4-step mechanism for nanocluster formation and agglomeration; (ii) a study addressing the question of whether the hydrogenation of olefins using (1,5-COD)PtII complexes proceeds via homogeneous or heterogeneous catalysis; and (iii) a comparison of the kinetics of transition-metal nanocluster formation and the kinetics of solid-state reactions. Recently, a new, 4-step mechanism was discovered for the nucleation, growth, and agglomeration of transition-metal nanoclusters, using a single Pt complex in the system under study. Herein, the mechanism is shown to be general to the formation of nanoclusters of at least four other metals. In addition, the effects of ligands, concentration, temperature, solvent, and stirring on the mechanism are examined. Several alternative mechanisms are ruled out, leaving the 4-step mechanism as the only one to date that can account for the observed kinetics. The question of "is it homogeneous or heterogeneous catalysis?" is addressed with respect to the hydrogenation of olefins using (1,5-COD)Pt II complexes. The data presented herein provide compelling evidence that these complexes are first reduced to Pt0 nanoclusters and/or bulk metal, which are the true hydrogenation catalysts. Included herein is a brief overview of the literature of Pt-catalyzed hydrosilylation reaction, with respect to the "is it homogeneous or heterogeneous catalysis?" question. The literature is replete with mechanisms describing solid-state phase transitions, the kinetics of which appear similar to the kinetics of transition-metal nanocluster formation. It is found that the solid-state equation can fit nanocluster formation kinetic data, and vice versa. This finding leads into a comparison of solid-state reaction mechanisms and the Finke-Watzky mechanism, with a focus on the strengths and limitations of each.

Finney, Eric E.

303

POROSITIES OF PROTOPLANETARY DUST AGGLOMERATES FROM COLLISION EXPERIMENTS  

SciTech Connect

The aggregation of dust through sticking collisions is the first step of planet formation. The basic physical properties of the evolving dust aggregates strongly depend on the porosity of the aggregates; e.g., mechanical strength, thermal conductivity, and the gas-grain coupling time. Also, the outcome of further collisions depends on the porosity of the colliding aggregates. In laboratory experiments we study the growth of large aggregates of {approx}3 mm to 3 cm through continuous impacts of small dust agglomerates of 100 {mu}m in size, consisting of {mu}m grains at different impact velocities. The experiments show that agglomerates grow by direct sticking as well as through gravitational reaccretion. The latter can be regarded as a suitable analog to the reaccretion of fragments by gas drag in protoplanetary disks. Experiments were carried out in the velocity range between 1.5 m s{sup -1} and 7 m s{sup -1}. With increasing impact velocities the volume filling factor of the resulting agglomerates increases from {phi} = 0.2 for 1.5 m s{sup -1} to {phi} = 0.32 for 7 m s{sup -1}. These values are independent of the target size. Extrapolation of the measured velocity dependence of the volume filling factor implies that higher collision velocities will not lead to more compact aggregates. Therefore, {phi} = 0.32 marks a degree of compaction suitable for describing structures forming at v > 6 m s{sup -1}. At small collision velocities below 1 m s{sup -1}, highly porous structures with {phi} Almost-Equal-To 0.10 will form. For intermediate collision velocities porosities vary. Depending on the disk model and resulting relative velocities, objects in protoplanetary disks up to decimeters in size might evolve from highly porous ({phi} Almost-Equal-To 0.10) to compact ({phi} = 0.32) with a more complex intermediate size range of varying porosity.

Teiser, J.; Engelhardt, I.; Wurm, G., E-mail: jens.teiser@uni-due.de [Faculty of Physics, University Duisburg-Essen, Duisburg (Germany)

2011-11-20

304

Flow cytometry: a promising technique for the study of silicone oil-induced particulate formation in protein formulations.  

PubMed

Subvisible particles in formulations intended for parenteral administration are of concern in the biopharmaceutical industry. However, monitoring and control of subvisible particulates can be complicated by formulation components, such as the silicone oil used for the lubrication of prefilled syringes, and it is difficult to differentiate microdroplets of silicone oil from particles formed by aggregated protein. In this study, we demonstrate the ability of flow cytometry to resolve mixtures comprising subvisible bovine serum albumin (BSA) aggregate particles and silicone oil emulsion droplets with adsorbed BSA. Flow cytometry was also used to investigate the effects of silicone oil emulsions on the stability of BSA, lysozyme, abatacept, and trastuzumab formulations containing surfactant, sodium chloride, or sucrose. To aid in particle characterization, the fluorescence detection capabilities of flow cytometry were exploited by staining silicone oil with BODIPY 493/503 and model proteins with Alexa Fluor 647. Flow cytometric analyses revealed that silicone oil emulsions induced the loss of soluble protein via protein adsorption onto the silicone oil droplet surface. The addition of surfactant prevented protein from adsorbing onto the surface of silicone oil droplets. There was minimal formation of homogeneous protein aggregates due to exposure to silicone oil droplets, although oil droplets with surface-adsorbed trastuzumab exhibited flocculation. The results of this study demonstrate the utility of flow cytometry as an analytical tool for monitoring the effects of subvisible silicone oil droplets on the stability of protein formulations. PMID:21146492

Ludwig, D Brett; Trotter, Joseph T; Gabrielson, John P; Carpenter, John F; Randolph, Theodore W

2010-12-10

305

Kinetics of oil dispersion in the absence and presence of block copolymers  

Microsoft Academic Search

Dispersion of oil into fine droplets is important in many applications, such as flotation, selective agglomeration, solvent extraction, wastewater treatment, and oil drilling. Size distribution of oil droplets determines the rate of mass transfer between the continuous and the disperse phase and the outcome of the process in these applications. A phenomenological model proposed describes droplet breakup in the turbulently

H. Polat; M. Polat; S. Chander

1999-01-01

306

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

2013-05-02

307

Design of sustained release fine particles using two-step mechanical powder processing: particle shape modification of drug crystals and dry particle coating with polymer nanoparticle agglomerate.  

PubMed

We attempted to prepare sustained release fine particles using a two-step mechanical powder processing method; particle-shape modification and dry particle coating. First, particle shape of bulk drug was modified by mechanical treatment to yield drug crystals suitable for the coating process. Drug crystals became more rounded with increasing rotation speed, which demonstrates that powerful mechanical stress yields spherical drug crystals with narrow size distribution. This process is the result of destruction, granulation and refinement of drug crystals. Second, the modified drug particles and polymer coating powder were mechanically treated to prepare composite particles. Polymer nanoparticle agglomerate obtained by drying poly(meth)acrylate aqueous dispersion was used as a coating powder. The porous nanoparticle agglomerate has superior coating performance, because it is completely deagglomerated under mechanical stress to form fine fragments that act as guest particles. As a result, spherical drug crystals treated with porous agglomerate were effectively coated by poly(meth)acrylate powder, showing sustained release after curing. From these findings, particle-shape modification of drug crystals and dry particle coating with nanoparticle agglomerate using a mechanical powder processor is expected as an innovative technique for preparing controlled-release coated particles having high drug content and size smaller than 100 ?m. PMID:23796831

Kondo, Keita; Ito, Natsuki; Niwa, Toshiyuki; Danjo, Kazumi

2013-06-21

308

[Effect of powder's particle size on the quantitative prediction of volatile oil content in Zanthoxylum bungeagum by NIR technique].  

PubMed

The traditional chemical methods to measure the volatile oil content of zanthoxylum bungeagum encounter some problems such as long time and low efficiency, so it is difficult to achieve rapid detection. One hundred forty-one samples including 74 zanthoxylum bungeagum maxim and 67 zanthoxylum schinifolium Sieb. et zucc were collected, from many provinces in China such as Shan Xi, Si Chuan, Gan Su, Chong Qing, Yun Nan, etc. Each sample was crushed and sorted to 8 kinds of powder samples according to the particle size of 120-mesh, 100-mesh, 80-mesh, 60-mesh, 40-mesh, 20-mesh, 10-mesh, respectively, including the material retained by the 10-mesh sieve. Then, each powder sample was labeled by one of the following serial numbers: 120, 100, 080, 060, 040, 020, 010 and 000. For each sample, the NIR spectra of 8 different kinds of particle size powders were measured using a Bruker MATRIX-I FT-NIR spectrometer. Then, the 8 different kinds of particle size powders of each sample were mixed uniformly. The volatile oil content was measured in each sample according to the distillation stipulated by the Forestry Standard of PRC-Quality Classify of Prickly Ash (LY/T 1652-2005). Based on near infrared spectroscopy technique and partial least squares (PLS), 8 calibration models of predicting volatile oil content were established by 141 powder samples with 8 different kinds of particle size. Experiments indicatd that the model was the best with the powder's particle size of 40-mesh and the determination coefficient (r2(141)) and the root mean square error of cross validation (RMSECV141) were 0.9364 and 0.421, respectively. The model was established by the calibration set with 105 samples with particle size of 40-mesh. Applying the model to the test set with 36 samples, the determination coefficient (r2(36)), the root mean square error of prediction (RMSEP36), the relative standard deviation (RSD36), and the ratio of prediction to deviation (RPD36) were 0.9233, 0.452, 11.66%, and 3.624, respectively. The model, based on the same sample set but optimized by OPUS 5.0, was developed by spectral data pretreatment of the Mean Centering+Vector Normalization in the spectral region of 6 100.1-5 774.2 cm(-1) and 4 601.6-4 424.2 cm(-1). Using the model to predict the test set, r2(36), RMSEP36, RSD36, and RPD36 were 0.9862, 0.192, 4.95%, and 8.517, respectively. The results showed that the model built by samples passed through 40-mesh screen was the best and rapid detection of volatile oil content in zanthoxylum bungeagum by NIR was feasible and efficient. PMID:18619296

Zhu, Shi-Ping; Wang, Gang; Yang, Fei; Kan, Jian-Quan; Guo, Jing; Qiu, Qing-Miao

2008-04-01

309

Modeling agglomeration processes in fluid-bed granulation  

SciTech Connect

Many agrochemicals are formulated as water dispersive granules through agglomeration, beginning with a fine powder ({approximately}1 {micro}m) and ending with granules on the order of 500 {micro}m. Powders are charged into a granulation system with a liquid binding agent, and granules are subsequently grown to an appropriate size. Granulation in fluid beds is presented using a mass conserving discretized population balance equation. Coalesce kernels governing the rate and extent of granulation are assumed dependent on the Stokes number, which is indirectly liked to important process variables (air and under flow rate, bed charge, bed geometry) such that the physical processes governing particle coalescence and rebound are correlated to process variables. A new coalescence kernel is proposed based on physical insight, simplicity, and deterministic equivalent modeling to account for uncertainty. This kernel is based on a Stokes number method where uncertainty in the Stokes number is characterized by polynomial chaos expansions. The magnitude of the coalescence kernel is proportional to the probability of the distribution of Stokes number exceeding a critical value. This mechanistic/semiempirical approach to fluid-bed agglomeration fosters an environment for process scaleup by eliminating specific equipment and process variable constraints to focus on the underlying mechanisms for proper scale-up procedures. Model predictions using this new kernel are then compared to experimental pilot-plant observations.

Cryer, S.A.

1999-10-01

310

Exploring Oil Pollution  

ERIC Educational Resources Information Center

|Discusses damages of oil tanker spillage to the marine organisms and scientists' research in oil pollution removal techniques. Included is a list of learning activities concerning the causes and effects of oil pollution and methods of solving the problem. (CC)|

Rillo, Thomas J.

1974-01-01

311

Exploring Oil Pollution  

ERIC Educational Resources Information Center

Discusses damages of oil tanker spillage to the marine organisms and scientists' research in oil pollution removal techniques. Included is a list of learning activities concerning the causes and effects of oil pollution and methods of solving the problem. (CC)

Rillo, Thomas J.

1974-01-01

312

Influence of the pan pelletizer rotational velocity and the particles size on the agglomeration of alumina oxide granules  

NASA Astrophysics Data System (ADS)

High fraction of agglomerates and better agglomerate strength are main purpose for every agglomeration process. For optimizing the agglomeration process of industrial produced granules, using liquid binders, it is necessary to understand the microinteractions between primary particles and binder and the marcointeractions between the agglomerates themselves. In order to investigate the influence of the rotational velocity of the pan pelletizer and the primary particle size on the fraction of agglomerates and the mechanical properties of the produced agglomerates, the obtained structures have to be basically analyzed. Agglomeration of industrial produced Alumina Oxide (?-Al2O3) granules is carried out in a rotating pan pelletizer. A 6 mass-% solution of viscoelastic polymer - hydroxypropyl methylcellulose (HPMC) is used as binder. The rotational velocity of the pelletizer pan is previously measured and calibrated. By changing the rotational velocity of the process chamber it was found that there are critical speed limits for the pan. The minimum critical velocity of the pelletizer plate does not provide enough contact collisions between the particles and the necessary kinetic level for agglomeration cannot be reached. The maximum critical velocity leads to higher rotational kinetic energy and this causes breakages of the agglomerates. It was also proven that the breakage strength of the agglomerates decreases with the reduction of the agglomerate size. The conclusions from the experimental work help us to understand the basics of agglomeration process and tend to develop and facilitate the operating with particle collectives in science and industry.

Radeva, Zheni; Müller, Peter; Tomas, Juergen

2013-06-01

313

The Effect of Different Oil Spill Remediation Techniques on Petroleum Hydrocarbon Elimination in Australian Bass ( Macquaria novemaculeata )  

Microsoft Academic Search

Petroleum hydrocarbons were investigated in juvenile Australian bass, Macquaria novemaculeata, following exposure to the water accommodated fraction (WAF) of Bass Strait crude oil, chemically dispersed crude oil, and\\u000a burnt crude oil. Each treatment was administered for 16 days either through the water column or through the diet (amphipod,\\u000a Allorchestes compressa). Polycyclic aromatic hydrocarbon (PAH) elimination was determined by measuring biliary

A. M. Cohen; D. Nugegoda; M. M. Gagnon

2001-01-01

314

Macrokinetics of Combustion of Monodisperse Agglomerates in the Flame of a Model Solid Propellant  

Microsoft Academic Search

The paper describes a procedure for studying the macrokinetics of combustion of agglomerates in a solid propellant flame using special samples of a model propellant generating monodisperse agglomerates. Empirical dependences of the incompleteness of aluminum combustion in the combustion products of a propellant based on ammonium perchlorate and HMX on time and pressure were established. The mass fraction of oxide

O. G. Glotov; V. E. Zarko; V. V. Karasev; T. D. Fedotova; A. D. Rychkov

2003-01-01

315

Compaction of agglomerates of aerosol nanoparticles: A compilation of experimental data  

Microsoft Academic Search

The compacting behavior of agglomerated aerosol nanoparticles in the size range between 7 and 150 nm was investigated using available literature data. We observed a characteristic behavior, which can be described by three separate steps. When comparing the first step, the compaction from agglomerates into spherules, differences could be observed for nanoparticles of different materials. It is seen from the available

M. N. A. Karlsson; K. Deppert; L. S. Karlsson; M. H. Magnusson; J.-O. Malm; N. S. Srinivasan

2005-01-01

316

Agglomeration of Sodium Bicarbonate in Vibrofluidized Bed: Process Analysis and Evaluation of CO2 Release  

Microsoft Academic Search

Agglomeration of sodium bicarbonate in a vibrofluidized bed using an aqueous polymeric suspension as binding agent was studied to determine the effects of vibration parameters (amplitude and frequency) and drying air temperature on process performance and product quality. Product quality was evaluated by determination and comparison of CO2 release from agglomerated and raw sodium bicarbonate. An experimental design was developed

S. C. S. Rocha; J. F. Nunes

2012-01-01

317

Agglomeration bonus: an incentive mechanism to reunite fragmented habitat for biodiversity conservation  

Microsoft Academic Search

This paper examines an experiment conducted to explore a voluntary incentive mechanism, the agglomeration bonus, designed to protect endangered species and biodiversity by reuniting fragmented habitat across private land. The goal is to maximize habitat protection and minimize landowner resentment. The agglomeration bonus mechanism pays an extra bonus for every acre a landowner retires that borders on any other retired

Gregory M. Parkhurst; Jason F. Shogren; Chris Bastian; Paul Kivi; Jennifer Donner; Rodney B. W. Smith

2002-01-01

318

Agglomeration of gibbsite Al(OH) 3 crystals in Bayer liquors. Influence of the process parameters  

Microsoft Academic Search

Agglomeration of gibbsite (Al(OH)3) crystals is an important stage of the Bayer process. In the present study, using a crystallizer working at constant supersaturation with time, we determine the agglomeration kinetics of gibbsite as a function of different experimental parameters. The effect of the crystallization temperature, supersaturation, seed mass, stirring rate and seed size is investigated. An interpretation of the

I. Seyssiecq; S. Veesler; R. Boistelle; J. M. Lamérant

1998-01-01

319

Crystal agglomeration is a major element in calcium oxalate urinary stone formation  

Microsoft Academic Search

Crystal agglomeration is a major element in calcium oxalate urinary stone formation. The effects of urines from 36 healthy subjects and 86 calcium oxalate renal stone formers on calcium oxalate monohydrate crystallization kinetics were studied using a seeded crystal growth method in which the solubility, the growth and the agglomeration of the crystals are measured as three separate and system-independent

Dik J Kok; Socrates E Papapoulos; Olav L M Bijvoet

1990-01-01

320

Impact of agglomeration state of nano- and submicron sized gold particles on pulmonary inflammation  

Microsoft Academic Search

BACKGROUND: Nanoparticle (NP) toxicity testing comes with many challenges. Characterization of the test substance is of crucial importance and in the case of NPs, agglomeration\\/aggregation state in physiological media needs to be considered. In this study, we have addressed the effect of agglomerated versus single particle suspensions of nano- and submicron sized gold on the inflammatory response in the lung.

Ilse Gosens; Jan Andries Post; Liset JJ de la Fonteyne; Eugene HJM Jansen; John W Geus; Flemming R Cassee; Wim H de Jong

2010-01-01

321

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

322

A MODEL FOR FINE PARTICLE AGGLOMERATION IN CIRCULATING FLUIDIZED BED ABSORBERS  

EPA Science Inventory

A model for fine particle agglomeration in circulating fluidized bed absorbers (CFBAS) has been developed. It can model the influence of different factors on agglomeration, such as the geometry of CFBAs, superficial gas velocity, initial particle size distribution, and type of ag...

323

Brownian Coagulation of Fractal Agglomerates: Analytical Solution Using the Log-Normal Size Distribution Assumption  

Microsoft Academic Search

An analytical solution to Brownian coagulation of fractal agglomerates in the continuum regime that provides time evolution of the particle size distribution is presented. The theoretical analysis is based on representation of the size distribution of coagulating agglomerates with a time-dependent log-normal size distribution function and employs the method of moments together with suitable simplifications. The results are found in

S. H. Park; R. Xiang; K. W. Lee

2000-01-01

324

Economies of scope and economies of agglomeration: The Goldstein-Gronberg contribution revisited  

Microsoft Academic Search

Following on from the work of Goldstein and Gronberg, it is argued that under certain conditions, internal economies of scope form the bases for two types of agglomeration economy. These differ from two better known types, which are based on internal and external economies of scale. A further two types of agglomeration economy are shown to derive from particular forms

John B. Parr

2004-01-01

325

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

326

Acoustic agglomeration of power-plant fly ash. A comprehensive semi-annual progress report  

SciTech Connect

Results obtained during the reporting period are presented. The agglomeration of submicron fly ash particles has been studied as a function of sound pressure level, sound frequency, loading, and exposure time. A second generation model of the agglomeration process is being developed. A high-frequency, high-intensity variable speed siren delivering at least 600 W at frequencies up to 4000 Hz has been developed and tested. Details on the design and operation are presented. The agglomeration chamber has been completely cleaned and the aerosol generating system has been rebuilt. A mathematical model of the acoustics of agglomeration is being developed. Preliminary results of computerized electron microscopic scanning of fly ash particles during agglomeration are presented. (DMC)

Reethof, G.

1980-02-01

327

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

PubMed

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. PMID:23848681

Born, Philip; Kraus, Tobias

2013-06-19

328

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

329

An Investigation of the Applicability of the In-situ Thermal Recovery Technique to the Beypazari Oil Shale  

Microsoft Academic Search

In this research, a 3-D reservoir model for steam recovery was used to study Beypazari oil shale. In addition, the reaction kinetics parameters of Beypazari oil shale were determined by using the Weijdema's reaction kinetics approach in order to evaluate the applicability of these thermal methods. In the analysis of reaction kinetics experiments, two different temperature regions were observed. In

M. V. Kok; S. Bagci

2010-01-01

330

The application of ESI maps with the GIS technique to coastal oil-spill cleanups in Taiwan  

Microsoft Academic Search

Fragile ecosystems and the harnessing of resources for human use are two major elements that have to coexist in coastal regions. The sensitivity of the coastal environment to oil spills and related cleanups depends on the presence of these resources, and can be assessed by the level of potential impact that would be caused by an oil spill. In this

Y.-C. Chen; L.-J. O'Yang

331

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.

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

2013-01-01

332

Investigations on a novel inductive concept frequency technique for the grading of oil palm fresh fruit bunches.  

PubMed

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

2013-02-07

333

Toxicity study of the oil dispersant Corexit 9527 on Macrobrachium rosenbergii (de Man) egg hatchability by using a flow-through bioassay technique  

Microsoft Academic Search

The effect of the oil-spill dispersant Corexit 9527 on egg-hatching rate of Macrobrachium rosenbergii (de Man) was studied by using an innovated flow-through bioassay technique. This bioassay method relies on the fact that M. rosenbergii fertilized eggs when detached from the mother prawn were able to hatch artificially. The flow-through system generated a stable and good water quality environment for

A. T. Law

1995-01-01

334

Characterization of chloramphenicol palmitate drug polymorphs by Raman mapping with multivariate image segmentation using a spatial directed agglomeration clustering method.  

PubMed

Chemical imaging analysis holds great potential in probing the chemical heterogeneity of samples with high spatial resolution and molecular specificity. This paper demonstrates the implementation of Raman mapping for microscopic characterization of tablets containing chloramphenicol palmitate polymorphs with the aid of a new multivariate image segmentation approach based on spatial directed agglomeration clustering. This approach performs the agglomeration clustering by stepwise merging the pixels possessing both spatial closeness and spectral similarity into clusters that define the image segmentation. The incorporation of spatial closeness into the clustering process enables the approach to improve the robustness and avoid poorly defined image segmentation arising from clusters with highly separated pixels. Additionally, the stepwise merging of clusters offers an F-statistic-based procedure to automatically ascertain the number of image segments. Raman mapping analysis of tablets containing two polymorphs of chloramphenicol palmitate followed by multivariate image segmentation reveals that the proposed technique offers the identification of each polymorph and a quantitative visualization of the spatial distribution of the polymorphs identified. This technique holds promise in rapid, noninvasive, and quantitative polymorph analysis for pharmaceutical production processes. PMID:16944877

Lin, Wei-Qi; Jiang, Jian-Hui; Yang, Hai-Feng; Ozaki, Yukihiro; Shen, Guo-Li; Yu, Ru-Qin

2006-09-01

335

Evaluation of physico-mechanical properties of drug-excipients agglomerates obtained by crystallization.  

PubMed

Spherical crystallization (SC) of carbamazepine (CBZ) was carried out for preparation of the agglomerates using the solvent change method. The potential of the intraagglomerate addition of sodium starch glycolate (SSG) as a disintegrant agent and povidone (PVP) as a hydrophilic polymer was also evaluated. The process of SC involved recrystallization of CBZ and its simultaneous agglomeration with additives. An ethanol:isopropyl acetate:water system was used where isopropyl acetate acted as a bridging liquid and ethanol and water as good and bad solvents, respectively. The agglomerates were characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (XRPD), and Scanning electron microscopy and were evaluated for yield, flowability, disintegration time and drug release. CBZ agglomerates exhibited significantly improved micromeritic properties as well as dissolution behavior in comparison to conventional drug crystals. The dissolution rate of drug from agglomerates was enhanced by inclusion of SSG, while addition of PVP to CBZ/SSG agglomerates led to reduction in the release rate of CBZ even below that of the conventional drug crystals. SC process can be considered as a suitable alternative to conventional granulation process to obtain agglomerates of CBZ with excipients with improved micromeritic properties and modified dissolution rate. PMID:20175665

Maghsoodi, M; Tajalli Bakhsh, A S

2010-02-22

336

Nanoparticle agglomeration in an evaporating levitated droplet for different acoustic amplitudes  

NASA Astrophysics Data System (ADS)

Radiatively heated levitated functional droplets with nanosilica suspensions exhibit three distinct stages namely pure evaporation, agglomeration, and finally structure formation. The temporal history of the droplet surface temperature shows two inflection points. One inflection point corresponds to a local maximum and demarcates the end of transient heating of the droplet and domination of vaporization. The second inflection point is a local minimum and indicates slowing down of the evaporation rate due to surface accumulation of nanoparticles. Morphology and final precipitation structures of levitated droplets are due to competing mechanisms of particle agglomeration, evaporation, and shape deformation. In this work, we provide a detailed analysis for each process and propose two important timescales for evaporation and agglomeration that determine the final diameter of the structure formed. It is seen that both agglomeration and evaporation timescales are similar functions of acoustic amplitude (sound pressure level), droplet size, viscosity, and density. However, we show that while the agglomeration timescale decreases with initial particle concentration, the evaporation timescale shows the opposite trend. The final normalized diameter can be shown to be dependent solely on the ratio of agglomeration to evaporation timescales for all concentrations and acoustic amplitudes. The structures also exhibit various aspect ratios (bowls, rings, spheroids) which depend on the ratio of the deformation timescale (tdef) and the agglomeration timescale (tg). For tdef

Tijerino, Erick; Basu, Saptarshi; Kumar, Ranganathan

2013-01-01

337

Nanosized rods agglomerates as a new approach for formulation of a dry powder inhaler  

PubMed Central

Background: Nanosized dry powder inhalers provide higher stability for poorly water-soluble drugs as compared with liquid formulations. However, the respirable particles must have a diameter of 1–5 ?m in order to deposit in the lungs. Controlled agglomeration of the nanoparticles increases their geometric particle size so they can deposit easily in the lungs. In the lungs, they fall apart to reform nanoparticles, thus enhancing the dissolution rate of the drugs. Theophylline is a bronchodilator with poor solubility in water. Methods: Nanosized theophylline colloids were formed using an amphiphilic surfactant and destabilized using dilute sodium chloride solutions to form the agglomerates. Results: The theophylline nanoparticles thus obtained had an average particle size of 290 nm and a zeta potential of ?39.5 mV, whereas the agglomerates were 2.47 ?m in size with a zeta potential of ?28.9 mV. The release profile was found to follow first-order kinetics (r2 > 0.96). The aerodynamic characteristics of the agglomerated nanoparticles were determined using a cascade impactor. The behavior of the agglomerate was significantly better than unprocessed raw theophylline powder. In addition, the nanoparticles and agglomerates resulted in a significant improvement in the dissolution of theophylline. Conclusion: The results obtained lend support to the hypothesis that controlled agglomeration strategies provide an efficient approach for the delivery of poorly water-soluble drugs into the lungs.

Salem, HF; Abdelrahim, ME; Eid, K Abo; Sharaf, MA

2011-01-01

338

Bed material agglomeration during fluidized bed combustion. Technical progress report, October 1, 1993--December 31, 1993  

SciTech Connect

During this quarter, agglomerates which formed in the FBC at Montana-Dakota Utilities (Heskett Station Unit 2 located in Bismarck, ND) were analyzed by x-ray diffraction analyses (XRD) for mineral determination; bulk chemical composition was determined by inductively coupled plasma spectroscopy; and polished sections were made for optical and scanning electron microscopy. Polarized-light microscopy was performed using a Zeiss research microscope. Individual mineral grains were analyzed using an ARL electron microprobe and a JOEL 840 scanning electron microscope. The agglomerate was found in the mechanical dust collector and was about ten centimeters in diameter with a dark-colored core and a greenish rim. The sample had voids up to ten millimeters in size; however, the agglomerate was hard to break apart. Bulk compositionally, the agglomerate consists primarily of calcium, silica, and alumina with relatively high abundances of iron (8 to 9 wt %), magnesium (5 to 9 wt %) and sodium (3 to 4 wt %). It is likely that the ``root`` cause of this agglomerate originated in the dense phase of the FBC bed. Because fluidized bed combustors work below the ash fusion temperature of coal ash, aluminosilicates (clays) in the ash probably became ``sticky`` due to fluxing reactions with pyrite (FeS{sub 2}) and perhaps alkalies (Na). This is indicated by the high amounts of iron, silica, and alumina in the agglomerate. Because of the size of the deposit, the bed particles probably agglomerated in the dust collector.

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

1994-01-01

339

Prediction of [3- 14C]phenyldodecane biodegradation in cable insulating oil-spiked soil using selected extraction techniques  

Microsoft Academic Search

This study investigated the use of an aqueous hydroxypropyl-?-cyclodextrin (HPCD) shake extraction in predicting microbial mineralisation and total loss of [3-14C]phenyldodecane associated activity in soils spiked with cable insulating oil; phenyldodecane represents a major constituent of cable insulating oil. Direct comparisons were made between freshly spiked and aged soils, and following composting. Soil was spiked with [3-14C]phenyldodecane (10mg kg?1) and

Nadia M. Dew; Graeme I. Paton; Kirk T. Semple

2005-01-01

340

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

Microsoft Academic Search

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 m³) of oil per field at a 15 to 20

Thomas C. Chidsey

2002-01-01

341

Transport and agglomeration of dust contaminant particles in reactive ion etch reactors  

NASA Astrophysics Data System (ADS)

Dust particle contamination in plasma etching reactors continues to be a major concern to microelectronic device manufacturers. Dust particulates as small as tens of nanometers in dimension can produce killer defects on the substrate surface. These contaminants are produced either through gas-phase nucleation processes in the discharge, or through interaction with surfaces in the reactor. Their transport is governed by the forces exerted upon them in the reactor, primarily electrostatic, ion drag, neutral drag, thermophoresis, and gravitational forces. Dust particulates collected from reactive ion etching (RIE) reactors are commonly found to be agglomerate structures consisting of smaller, spherical 'primary particles.' These primary particles grow to a terminal size in the reactor and then combine to form the larger agglomerates. This agglomeration phenomenon requires a certain amount of kinetic energy from the primary particles, which typically charge negatively in such discharges. With sufficient kinetic energy, primary particles can overcome their mutual electrostatic repulsion and join together to form an agglomerate particle. The transport and agglomeration of dust particles in RIE reactors has been studied using a series of numerical simulations. These computational models have demonstrated that both dust transport and agglomeration are highly dependent on reactor geometry and discharge operating conditions, as well as the size of the primary particle. In general, higher radio-frequency (RF) powers and larger primary particles lead to more agglomeration. This in turn typically results in a larger amount of substrate contamination. The morphology of the agglomerates formed was also found to be dependent on plasma conditions. Agglomerates generally grow either in a diffusive or ballistic manner. Neutral gas flow in the reactor has been found to be a useful means of controlling contamination. Higher flow rates can sweep dust particles away from sensitive areas of the reactor before they reach the surfaces.

Huang, Frederick Yi-Kai

342

Simulation of cold flow in agglomerating reactors. Topical report No. 1  

SciTech Connect

JAYCOR has developed a computer code for modeling fluid flows containing agglomerating particles, with the goal of providing a method for optimization and scale-up of certain coal gasification reactors. The physical and chemical processes modeled in the computer code range from fluid and particle flow with heat transfer, to pyrolysis, mixing, and agglomeration of the coal. The initial effort has been directed toward a simulation of the Westinghouse Electric Corporation's devolatilizer unit, which uses a draft tube and fluidized bed for devolatilizing coal, while limiting the agglomeration of the coal particles. The simulation code is flexible and can easily be adapted to study the behavior of other reactors.

Scharff, M.F.; Klein, H.H.; Chan, R.K.C.; Dietrich, D.E.; Goldman, S.R.; Sperling, J.L.

1980-07-01

343

Numerical estimation of the restitution coefficient for dry and wet agglomerates  

NASA Astrophysics Data System (ADS)

In this contribution a novel simulation tool, which is able to predict the agglomerate deformation and breakage during different loading conditions, was developed. This simulation system is based on the Discrete Element Method (DEM). For a better understanding of the soft, non-elastic deformation behaviour of wet and dry agglomerates, the models of liquid and solid bridges have been implemented in the DEM to perform a detailed simulation. As a result, the dependency of the restitution coefficient on the viscosity of the binder, impact velocity and agglomerate size and shape were obtained.

Antonyuk, Sergiy; Dosta, Maksym; Heinrich, Stefan

2013-06-01

344

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

2010-10-30

345

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

346

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

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

Sivayoganathan, Mugunthan; Tan, Bo; Venkatakrishnan, Krishnan

2012-11-09

347

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  

NASA Astrophysics Data System (ADS)

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.

Sivayoganathan, Mugunthan; Tan, Bo; Venkatakrishnan, Krishnan

2012-11-01

348

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

349

Understanding the influence of powder flowability, fluidization and de-agglomeration characteristics on the aerosolization of pharmaceutical model powders.  

PubMed

The aim of this study was to investigate the influence of the intrinsic inter-particulate cohesion of model pharmaceutical powders on their aerosolization from a dry powder inhaler. Two cohesive poly-disperse lactose powders with median particle sizes of around 4 and 20 microm were examined. The results showed that after dry coating with magnesium stearate, their flowability, fluidization and de-agglomeration behaviours could be substantially improved, as indicated by powder rheometry, shear testing and laser diffraction aerosol testing. This was achieved by reducing their cohesiveness via surface modification. In contrast to some previous reports, this study demonstrated how powder aerosolization may be improved more significantly and consistently (for widely varying air flow rates) by substantially reducing their inter-particulate cohesive forces. This study contributes to the understanding of the relationship between intrinsic cohesive nature and bulk properties such as flowability, fluidization and de-agglomeration and its impact on their aerosolization, which is fundamental and critical in the optimal design of dry powder inhaler formulations. The intensive mechanical dry coating technique also demonstrated a promising potential to improve aerosolization efficiency of fine cohesive model powders. PMID:20433919

Zhou, Qi Tony; Armstrong, Brian; Larson, Ian; Stewart, Peter J; Morton, David A V

2010-04-28

350

Evaluation of acoustic agglomerator for high temperature, high pressure particulate control. Task 13 final report.  

National Technical Information Service (NTIS)

This technical report gives a description of the high temperature, high pressure acoustic agglomerator (HPHT AA) project at Penn State University's High Intensity Acoustic Laboratory. The basic purpose of Task Order 13 was to demonstrate the effectiveness...

G. H. Koopmann G. Reethof

1989-01-01

351

Engineering the size and density of silicon agglomerates by controlling the initial surface carbonated contamination  

NASA Astrophysics Data System (ADS)

Actually, thermally induced thin-films dewetting silicon in the silicon-on-insulator is a way to obtain silicon agglomerates with a size and a density fixed by the silicon film thickness. In this paper we report a new method to monitor both the size and the density of the Si agglomerates thanks to the deposition of a carbon-like layer. We show that using a 5-nm thick layer of silicon and additional ?1-nm carbonated layer; we obtain agglomerates sizes ranging from 35 nm to 60 nm with respectively an agglomerate density ranging from 38 ?m-2 to 18 ?m-2. Additionally, for the case of strained silicon films an alternative dewetting mechanism can be induced by monitoring the chemical composition of the sample surface.

Borowik, ?.; Chevalier, N.; Mariolle, D.; Martinez, E.; Bertin, F.; Chabli, A.; Barbé, J.–C.

2013-04-01

352

Simulation of Aerosol Agglomeration in the Free Molecular and Continuum Flow Regimes.  

National Technical Information Service (NTIS)

The formation of high temperature aerosol agglomerates is simulated by following the Langevin trajectory of each particle with the boundary condition that the particles stick upon collision. Both the free molecular and continuum flow are treated. A new de...

G. W. Mulholland H. Baum R. D. Mountain

1986-01-01

353

Spatial Extent of Agglomeration Economies: Evidence from Three U.S. Manufacturing Industries.  

National Technical Information Service (NTIS)

The spatial extent of localized agglomeration economies constitutes one of the central current questions in regional science. It is crucial for understanding firm location decisions and for assessing the influence of proximity in shaping spatial patterns ...

J. Drucker

2012-01-01

354

Mitigation of Copper Corrosion and Agglomeration in APS Process Water Systems.  

National Technical Information Service (NTIS)

Copper corrosion has been observed in process water (PW) systems at the Advanced Photon Source (APS) dating to the early postcommissioning phase of the project. In time, copper corrosion products agglomerated significantly in certain preferred locations. ...

R. Dortwegt C. Putman E. Swetin

2002-01-01

355

Switching between crystallization and amorphous agglomeration of alkyl thiol-coated gold nanoparticles.  

PubMed

Crystalline and amorphous materials composed of the same atoms exhibit strikingly different properties. Likewise, the behavior of materials composed of mesoscale particles depends on the arrangement of their constituent particles. Here, we demonstrate control over particle arrangement during agglomeration. We obtain disordered and ordered agglomerates of the same alkyl thiol-coated gold nanoparticles depending on temperature and solvent. We find that ordered agglomeration occurs exclusively above the melting temperature of the ligand shells. Many-particle simulations show that the contact mechanics of the ligand shells dominate the order-disorder transition: Purely spherical particle-particle interactions yield order, whereas localized "stiction" between the ligand shells leads to disorder. This indicates that the "stickiness" and the packing of the agglomerates can be switched by the state of the ligand shells. It suggests that contact mechanics govern ordering in a wide range of nanoparticles. PMID:23005995

Geyer, Tihamér; Born, Philip; Kraus, Tobias

2012-09-17

356

The in Vivo Survival of Coombs Positive Autologous Erythrocytes Produced by Agglomeration.  

National Technical Information Service (NTIS)

Coombs positive erythrocytes were observed following the perservation of autologous, human erythrocytes using flycerol, slow freezing, and agglomeration. In 22 of 48 autotransfusions, the preserved erythrocytes were Coombs positive when tested with an ant...

C. R. Valeri

1965-01-01

357

Switching Between Crystallization and Amorphous Agglomeration of Alkyl Thiol-Coated Gold Nanoparticles  

NASA Astrophysics Data System (ADS)

Crystalline and amorphous materials composed of the same atoms exhibit strikingly different properties. Likewise, the behavior of materials composed of mesoscale particles depends on the arrangement of their constituent particles. Here, we demonstrate control over particle arrangement during agglomeration. We obtain disordered and ordered agglomerates of the same alkyl thiol-coated gold nanoparticles depending on temperature and solvent. We find that ordered agglomeration occurs exclusively above the melting temperature of the ligand shells. Many-particle simulations show that the contact mechanics of the ligand shells dominate the order-disorder transition: Purely spherical particle-particle interactions yield order, whereas localized “stiction” between the ligand shells leads to disorder. This indicates that the “stickiness” and the packing of the agglomerates can be switched by the state of the ligand shells. It suggests that contact mechanics govern ordering in a wide range of nanoparticles.

Geyer, Tihamér; Born, Philip; Kraus, Tobias

2012-09-01

358

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

359

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

2011-11-07

360

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

361

Nanostructured cerium oxide: preparation and properties of weakly-agglomerated powders  

Microsoft Academic Search

Nanocrystalline powders of cerium oxide were prepared from cerium(III) nitrate solution by a two-stage precipitation process which yielded weakly-agglomerated powders with a crystallite size smaller than 5nm. Hydrogen peroxide was added to cerium nitrate at 5°C to slowly oxidise Ce3+ to Ce4+ and thereby initiate homogeneous precipitation with the formation of dense spherical agglomerates. The precipitation process was completed by

Boro Djuri?i?; Stephen Pickering

1999-01-01

362

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

363

D. Jianping - Agglomeration Effects in Manufacturing Location - Are there any Country’s Preferences?  

Microsoft Academic Search

Geographic location of a firm reveals its country’s preference. This paper examines the agglomeration effects of the location of 1.5.5. and Japanese manufacturing firms within China’s 30 administrative regions during the period 1981—4996. The empirical results from the Conditional Logit Model (CLM) indicate that agglomeration effects exist in both countries’ site choices, though they are varied in degree by sectors

Ding Jianping

1999-01-01

364

A model for the collision efficiency of shear-induced agglomeration involving polymer bridging  

Microsoft Academic Search

An expression is derived in terms of key dimensionless groups, including a group for steric interaction, to determine the collision efficiency for shear-induced agglomeration of non-colloidal particulate suspensions. Agglomeration is assumed to take place due to bridging of polymer layers on colliding particles. The forces considered arise due to the van der Waals, double-layer, steric and hydrodynamic interactions. The expression

Sushant Agarwal; Rakesh K. Gupta; Deepak Doraiswamy

2009-01-01

365

Characterizing the dynamic behavior of nano-TiO 2 agglomerates in suspensions by photocorrelation spectroscopy  

Microsoft Academic Search

Metal oxide nanoparticles are small but easily form agglomerates in suspension, depending on the strength of particle–particle\\u000a and particle–media interactions. To understand the agglomeration behavior of nanoparticles in media and relate to it to product\\u000a performance testing, measurement methods are desired to characterize highly scattering metal oxide nanoparticle suspensions\\u000a without dilution. In this article, we describe the advantages of using

I-Hsiang Tseng; Stephanie S. Watson; Li-Piin Sung

2011-01-01

366

The Location of Japanese Investments in China: Agglomeration Effects, Keiretsu, and Firm Heterogeneity  

Microsoft Academic Search

Conditional logit analysis of locational choices by Japanese electronics manufacturers in China's regions and provinces during 1990–1995 confirms a major impact of general industry, Japanese, and keiretsu-specific agglomeration benefits. The effects of key determinants of locational choice vary substantially by investor size and market orientation of manufacturing plants. Small and medium-sized enterprises are more sensitive to Japanese agglomeration and prefer

René Belderbos; Martin Carree

2002-01-01

367

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

368

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

369

Feasibility study on oil droplet flow investigations inside aero engine bearing chambers -- PDPA techniques in combination with numerical approaches  

Microsoft Academic Search

The present paper deals with oil droplet flow phenomena in aero engine bearing chambers. An experimental investigation of droplet sizes and velocities utilizing a Phase Doppler Particle Analyzer (PDPA) has been performed for the first time in bearing chamber atmospheres under real engine conditions. Influences of high rotational speeds are discussed for individual droplet size classes. Although this is an

A. Glahn; M. Kurreck; M. Willmann; S. Wittig

1996-01-01

370

Effects of processing techniques on the natural colourings and the other functional constituents in virgin olive oil  

Microsoft Academic Search

The effects of two new enzyme processing aids, Bioliva and Rapidase adex D, and that of the olive paste malaxation temperature factor on the composition of natural colourings (chlorophylls, xanthophylls, and carotenes) and the chromatic parameters (chroma, brightness, and hue) have been investigated in virgin olive oils. Other major analytical variables (secoiridoid derivatives, tocopherols, volatiles, sensory scoring, oxidative stability, and

A. Ranalli; A. Malfatti; L. Lucera; S. Contento; E. Sotiriou

2005-01-01

371

Variation in accumulation of heavy metals in different verities of sunflower seed oil with the aid of multivariate technique  

Microsoft Academic Search

In this work, three heavy metals (HMs) cadmium, lead, and zinc were determined in 16 newly breaded varieties of sunflower seed oil, using atomic absorption spectrometry, prior to use of microwave-assisted acid digestion method (MWD). The accuracy of the proposed method was studied by standard addition method and values obtained by conventional wet acid digestion methods (CAM) on same samples.

Rehana Ansari; Tasneem Gul Kazi; Muhammad Khan Jamali; Muhammad Balal Arain; Muhammad Dowood Wagan; Nusrat Jalbani; Hassan Imran Afridi; Abdul Qadir Shah

2009-01-01

372

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

2012-12-19

373

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

Microsoft Academic Search

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,

G. A. Raine; N. Smith

1996-01-01

374

The Physics of Protoplanetesimal Dust Agglomerates. VII. The Low-velocity Collision Behavior of Large Dust Agglomerates  

NASA Astrophysics Data System (ADS)

We performed micro-gravity collision experiments in our laboratory drop tower using 5 cm sized dust agglomerates with volume filling factors of 0.3 and 0.4, respectively. This work is an extension of our previous experiments reported in Beitz et al. to aggregates of more than one order of magnitude higher masses. The dust aggregates consisted of micrometer-sized silica particles and were macroscopically homogeneous. We measured the coefficient of restitution for collision velocities ranging from 1 cm s-1 to 0.5 m s-1, and determined the fragmentation velocity. For low velocities, the coefficient of restitution decreases with increasing impact velocity, in contrast to findings by Beitz et al. At higher velocities, the value of the coefficient of restitution becomes constant, before the aggregates break at the onset of fragmentation. We interpret the qualitative change in the coefficient of restitution as the transition from a solid-body-dominated to a granular-medium-dominated behavior. We complement our experiments by molecular-dynamics simulations of porous aggregates and obtain a reasonable match to the experimental data. We discuss the importance of our experiments for protoplanetary disks, debris disks, and planetary rings. This work is an extension to the previous work of our group and gives new insight into the velocity dependency of the coefficient of restitution due to improved measurements, better statistics, and a theoretical approach.

Schräpler, Rainer; Blum, Jürgen; Seizinger, Alexander; Kley, Wilhelm

2012-10-01

375

THE PHYSICS OF PROTOPLANETESIMAL DUST AGGLOMERATES. VII. THE LOW-VELOCITY COLLISION BEHAVIOR OF LARGE DUST AGGLOMERATES  

SciTech Connect

We performed micro-gravity collision experiments in our laboratory drop tower using 5 cm sized dust agglomerates with volume filling factors of 0.3 and 0.4, respectively. This work is an extension of our previous experiments reported in Beitz et al. to aggregates of more than one order of magnitude higher masses. The dust aggregates consisted of micrometer-sized silica particles and were macroscopically homogeneous. We measured the coefficient of restitution for collision velocities ranging from 1 cm s{sup -1} to 0.5 m s{sup -1}, and determined the fragmentation velocity. For low velocities, the coefficient of restitution decreases with increasing impact velocity, in contrast to findings by Beitz et al. At higher velocities, the value of the coefficient of restitution becomes constant, before the aggregates break at the onset of fragmentation. We interpret the qualitative change in the coefficient of restitution as the transition from a solid-body-dominated to a granular-medium-dominated behavior. We complement our experiments by molecular-dynamics simulations of porous aggregates and obtain a reasonable match to the experimental data. We discuss the importance of our experiments for protoplanetary disks, debris disks, and planetary rings. This work is an extension to the previous work of our group and gives new insight into the velocity dependency of the coefficient of restitution due to improved measurements, better statistics, and a theoretical approach.

Schraepler, Rainer; Blum, Juergen [Institut fuer Geophysik und extraterrestrische Physik, University of Braunschweig Mendelssohnstr. 3, D-38106 Braunschweig (Germany); Seizinger, Alexander; Kley, Wilhelm, E-mail: r.schraepler@tu-bs.de [Institut fuer Astronomie und Astrophysik, University of Tuebingen Auf der Morgenstelle 10, D-72076 Tuebingen (Germany)

2012-10-10

376

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

377

The role of particle engineering in relation to formulation and de-agglomeration principle in the development of a dry powder formulation for inhalation of cetrorelix.  

PubMed

We formulated cetrorelix acetate, as an adhesive mixture for use in dry powder inhalation. To achieve the highest possible deposition efficiency we investigated both the influence of different micronization techniques and different inhalers. The Novolizer with an air classifier as the powder de-agglomeration principle and the ISF inhaler were used for in vitro deposition experiments (cascade impaction). Micronization by milling as the classical approach and micronization by spray drying and spray freeze drying as advanced particle engineering techniques were investigated to determine whether advanced techniques are necessary to obtain high fine particle fractions (FPF) for this specific drug. It was found that the effects obtained with a certain micronization technique depended on the complex interaction of the physical characteristics of the drug substance with the type of formulation chosen, as well as with the de-agglomeration principle used. The combination of particle engineering by spray drying and the use of the air classifier technology resulted in a fine particle fraction of 66%, while spray freeze drying yielded extremely fragile particles resulting in a FPF of only 25%. The behaviour of the milled material showed similar trends as the spray dried material but FPF values were lower. It was concluded that when a drug is to be formulated as a powder for inhalation with high fine particle fractions, it is profitable to use advanced particle engineering techniques, however the applied technique should be tuned with the characteristics of the formulation type and process as well as with device development. PMID:15451002

Zijlstra, Gerrit S; Hinrichs, Wouter L J; de Boer, Anne H; Frijlink, Henderik W

2004-10-01

378

Shale oil stabilization with a hydroprocessor  

SciTech Connect

A process is provided to produce, stabilize, dedust and upgrade synthetic oil, such as shale oil. In the process, synthetic fuels, such as oil shale, tar sands and diatomite are retorted with heat carrier material to liberate an effluent product stream comprising hydrocarbons and entrained particulates of dust. In order to minimize polymerization of the product stream and agglomerate the dust, the product stream is stabilized, upgraded, and pretreated prior to dedusting, in a hydroprocessor, such as an ebullated bed reactor, with a hydroprocessing gas in the presence of a catalyst. The hydroprocessing gas can be hydrogen, scrubbed fractionator gases, or hydrocarbon-enriched hydroprocessor off gases.

York, E. D.; Johnson, D. M.; Miller, P. B.

1985-10-22

379

Study of the polymerization of anthracene oil with AlCl3 by chromatography and related techniques.  

PubMed

The structure and composition of products from the reaction of anthracene oil with anhydrous AlCl3 have been examined. Size-exclusion chromatography has been carried out using a column with polystyrene-polydivinylbenzene as stationary phase, 1-methyl-2-pyrrolidinone at 80 degrees C as eluent and variable-wavelength UV-absorption detection. This system provides a chromatogram of the sample with several peaks. Molecular masses corresponding to these peaks were estimated using a calibration curve obtained with polycyclic aromatic hydrocarbon standards, ranging from 92 to 532 u. The most abundant compounds of the substrate were dimers and trimers of the main anthracene oil components. These results are corroborated on a qualitative level by synchronous UV-fluorescence spectra. PMID:11442030

Bermejo, J; Fernández, A L; Granda, M; Suelves, I; Herod, A A; Kandiyoti, R; Menéndez, R

2001-06-15

380

Study of the polymerization of anthracene oil with AlCl 3 by chromatography and related techniques  

Microsoft Academic Search

The structure and composition of products from the reaction of anthracene oil with anhydrous AlCl3 have been examined. Size-exclusion chromatography has been carried out using a column with polystyrene–polydivinylbenzene as stationary phase, 1-methyl-2-pyrrolidinone at 80°C as eluent and variable-wavelength UV-absorption detection. This system provides a chromatogram of the sample with several peaks. Molecular masses corresponding to these peaks were estimated

J. Bermejo; A. L. Fernández; M. Granda; I. Suelves; A. A. Herod; R. Kandiyoti; R. Menéndez

2001-01-01

381

Increased oil production and reserves from improved completion techniques in the Bluebell Field, Uinta Basin, Utah. Annual report, October 1, 1996--September 30, 1997  

SciTech Connect

Wells in the Bluebell field are typically completed by perforating 40 or more beds over 1,000 to 3,000 vertical ft, them stimulating the entire interval with hydrochloric acid. This technique is often referred to as the shot gun completion. The shot-gun 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. A two-year characterization study involved detailed examination of outcrop, core, well logs, surface and subsurface fractures, produced oil-field waters, engineering parameters of the two demonstration wells, and analysis of past completion techniques and effectiveness. The study was intended to improve the geologic characterization of the producing formations and thereby develop completion techniques specific to the producing beds or facies instead of a shot gun approach to stimulating all the beds. The characterization did not identify predictable-facies or predictable-fracture trends within the vertical stratigraphic column as originally hoped. Advanced logging techniques can identify productive beds in individual wells. A field-demonstration program was developed to use cased-hole advanced logging techniques in two wells and recompletion the wells at two different scales based on the logging. The first well was going to be completed at the interval scale using a multiple stage completion technique (about 500 ft per stage). The second well will be recompleted at the bed-scale using bridge plug and packer to isolate three or more beds for stimulation. These recompletion will show which logs are most effective in identifying productive beds and what scale of completion is most cost effective. The third demonstration will be the logging and completion of a new well using the logs and completion scale or technique most effective in the previous demonstrations.

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

1998-05-01

382

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

383

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

NASA Astrophysics Data System (ADS)

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 camera was used with a chopper wheel to give droplet flame diameter vs. time measurements of the burning droplets in flight, from which bum-rate laws were developed. A high-speed video CCD was used with high-magnification optics in order to image the flame/smoke cloud surrounding the burning liquid droplets. The intensity profiles of the droplet images were de-convoluted using an Abel inversion to give true intensity profiles. Both single and agglomerated droplets were studied, where agglomerates are comprised of hundreds of parent particles or more. The Abel inversion results show that the relative smoke cloud size is not constant with diameter, but instead grows as the droplet shrinks, by ˜D -0.5, for both the single and agglomerated droplets. Measured diameter trajectories show that for single droplets, the diameter law is D 0.75 = DO0.75 = 8·t [mu m, msec], and for agglomerated droplets, D 1.0 = Do1.0 - 20·t, such that the single droplets burn faster than the agglomerates. For both single and agglomerated droplets, the burning rate slope k did not change significantly over the chamber pressure studied. Lastly, a model was developed to describe the oxide cap accumulation on the droplet surface from the oxide smoke cloud surrounding the droplet. Results suggest that less oxide accumulates in high-pressure SRMs when considering mass burning rates for different relative cap sizes. The thermophoretic force, which can control oxide transport only over the cap, decreases with pressure.

Melcher, John Charles, IV

2001-07-01

384

Contribution of Local Agglomeration Economies to Productive Efficiency: Stochastic Frontier Estimation with Establishment-level Data on Japanese Manufactures (Japanese)  

Microsoft Academic Search

There are two types of local industrial agglomeration of economic activity. One is the clustering of like-kind businesses—small and medium-sized companies, plants, and other types of establishments belonging to the same industrial group—in a specific geographic area. The other is the agglomeration of individuals, typically, employees of a large-scale company. The former type of agglomeration relates to localization economies, whereas

NAKAMURA Ryohei

2011-01-01

385

Reliability of non-destructive test techniques in the inspection of pipelines used in the oil industry  

Microsoft Academic Search

The aim of this work is to evaluate the reliability of non-destructive test (NDT) techniques for the inspection of pipeline welds employed in the petroleum industry. Radiography, manual and automatic ultrasonic techniques using pulse-echo and time of flight diffraction (TOFD) were employed. Three classes of defects were analyzed: lack of penetration (LP), lack of fusion (LF) and undercut (UC). The

A. A. Carvalho; J. M. A. Rebello; M. P. V. Souza; L. V. S. Sagrilo; S. D. Soares

2008-01-01

386

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

387

Studies of Agglomeration and Rheology of Hydrate Slurries  

Microsoft Academic Search

Abstract Since the discovery that clathrate hydrates block pipelines they have been of interest to the oil and gas industries. Work initially focused on predicting the thermodynamics of clathrate hydrate formation so that clathrate hydrates could be avoided. Recently the industry has moved from this heuristic of avoidance to one of risk management. To pre- vent clathrate hydrate blockages the

Patrick Joseph Rensing

388

Polarized light scattering technique for morphological characterization of waterborne pathogens  

Microsoft Academic Search

We have recently developed an elliptically polarized light scattering (EPLS) technique to characterize the morphology of fine particles suspended in an optically non-absorbing medium such as water. This technique provides the size distribution, shape and agglomeration characteristics of suspended particles. This technique can be used to detect various types of biological pathogens such as bacteria, protozoa and viruses in potable

Venkat V. Devarakonda; Sivakumar Manickavasagam

2009-01-01

389

Removal of Ash from Pulverized Ccoal.  

National Technical Information Service (NTIS)

The purpose of this research project was to apply the technique known variously as spherical agglomeration, oil emulsion, or oil agglomeration, to the cleaning of pulverized New Mexico coal for power station use.

G. Purcell

1978-01-01

390

Development of Photocatalytic Coating Sprayed Using Agglomerated TiO2 Nano Particles  

NASA Astrophysics Data System (ADS)

TiO2 coatings were prepared by High Velocity Oxy-Fuel (HVOF) spraying using agglomerated nano-TiO2 powders with mean diameters of 30˜35 ?m, of which primary particle sizes were 200nm, 30nm and 7nm. The effects of spraying conditions on microstructure, anatase phase ratio and primary particle size have been investigated and then photocatalytic property was also evaluated. The anatase phase ratio decreased drastically with increasing fuel gas pressure in the case of agglomerated 7nm powder (P7 powder), while higher anatase ratio could be obtained in the case of agglomerated 200nm and 30nm powders (P200 and P30 powders). The particles of anatase phase grew during spraying in the case of agglomerated 7nm and 30nm powders. Especially, in the case of 7nm powders, they haw become three times larger compared to as-agglomerated powders, while they have hardly changed in the case of 200nm powders. These coatings showed photocatalytic degradation of gaseous acetaldehyde (CH3CHO). As a result of experiments, it was clarifid that the main factors affecting photocatalytic properties were the anatase ratio and particle size in the sprayed coating.

Yasuoka, Junichi; Nakade, Katsuyuki; Ohmori, Akira

391

Experimental investigation on agglomeration of coal-fired PM10 in uniform magnetic field  

NASA Astrophysics Data System (ADS)

Agglomeration experiments on fly ash particles in the size range of 0.023-9.314 ?m were conducted in a uniform magnetic field. The fly particles were produced from combustion of bituminous coal originated in Dongshen, China. A dedicated fluidized bed aerosol generator was developed to disperse particles to generate aerosol with constant rate. The aerosol particles from the generator underwent agglomeration during passing through the magnetic field. The variation in particles number concentration induced by agglomeration was measured in real time by Electrical Low Pressure Impactor (ELPI). The effects of the particle size, the magnetic flux density, the particle residence time in the magnetic field, the total particle mass concentration and the average gas velocity on particle agglomeration were examined. Experimental results indicate that the removal efficiencies for the midsized particles are higher than those for the smaller and the bigger ones. Single-sized and total particle removal efficiencies can be enhanced by rasing the magnetic flux density, the total particle mass concentration, the particle residence time in the magnetic field or reducing the average gas velocity. When particles are satuatedly magnetized, the magnetic flux density has no effect on their agglomeration.

Li, Yongwang; Zhao, Changsui; Wu, Xin; Lu, Duanfeng; Han, Song

2007-06-01

392

Experimental development of a two-stage fluidized-bed/cyclonic agglomerating incinerator  

SciTech Connect

The Institute of Gas Technology (IGT) is conducting an experimental program to develop and test through pilot-plant scale of operation, IGT's two-stage fluidized-bed/cyclonic agglomerating incinerator (TSI). The TSI is based on combining the fluidized-bed agglomeration/gasification technology and the cyclonic combustion/incineration technology, which have been developed at IGT over many years. The TSI is a unique and extremely flexible combustor that can operate over a wide range of conditions in the fluidized-bed first stage from low temperature (desorption) to high temperature (agglomeration) including gasification of high-Btu wastes. The TSI can easily and efficiently destroy solid, liquid and gaseous organic wastes, while containing solid inorganic contaminants within an essentially non-leachable glassy matrix, suitable for disposal in an ordinary landfill. This paper presents the results of tests conducted in a batch, fluidized-bed bench-scale unit (BSU) with commercially available clean'' top soil and the same soil spiked with lead and chromium compounds. The objectives of these tests were to determine the operating conditions necessary to achieve soil agglomeration and to evaluate the leaching characteristics of the soil agglomerates formed. 7 refs., 7 figs., 6 tabs.

Mensinger, M.C.; Rehmat, A.; Bryan, B.G.; Lau, F.S. (Institute of Gas Technology, Chicago, IL (United States)); Shearer, T.L. (Environmental Protection Agency, Cincinnati, OH (United States)); Duggan, P.A. (Gas Research Inst., Chicago, IL (United States))

1991-01-01

393

Prevention of structural perturbations and aggregation upon encapsulation of bovine serum albumin into poly(lactide-co-glycolide) micropheres using the solid-in-oil-in water technique.  

PubMed

Bovine serum albumin (BSA) was encapsulated into poly(lactide-co-glycolide) (PLG) microspheres by a solid-in-oil-in-water (s/o/w) technique. We tested whether perturbations in BSA secondary structure could be minimized during encapsulation by using trehalose and how this would influence BSA aggregation and release. BSA secondary structure was monitored noninvasively by Fourier-transform infrared spectroscopy. When BSA was co-lyophilized with trehalose, lyophilization-induced structural perturbations were significantly reduced. The formulation obtained (BSA-Tre) was encapsulated into PLG microspheres and, by optimizing critical encapsulation parameters, a loading efficiency of 85% was achieved. However, due to the loss of the excipient in the o/w emulsion step, the structure of BSA-Tre was more perturbed than before encapsulation. Excipient-loss and encapsulation-induced structural perturbations could be prevented by saturating the aqueous phase in the o/w step with trehalose and by using the organic solvent chloroform. This in turn reduced the formation of soluble BSA aggregates. BSA was released from PLG microspheres using the improved formulations with an initial release in 24 h of not more than 22%, followed by a sustained release over at least 2 weeks. In summary, optimization of the encapsulation conditions in the s/o/w procedure resulted in the encapsulation of BSA without procedure-induced structural perturbations and minimized the release of aggregated protein. This demonstrates that the s/o/w technique is an excellent alternative to the most common encapsulation procedure, namely the water-in-oil-in-water technique. PMID:11518019

Castellanos, I J; Cuadrado, W O; Griebenow, K

2001-08-01

394

Superhydrophobic Materials Technology: PVC Bonding Techniques.  

National Technical Information Service (NTIS)

The purpose of the technology maturation project was to develop an enhanced application technique for applying diatomaceous earth with pinned polysiloxane oil to PVC pipes and materials. The oil infiltration technique is applied as a spray of diluted oil ...

M. Efird S. R. Hunter

2011-01-01

395

Shipboard Oil in Water Monitor.  

National Technical Information Service (NTIS)

Laboratory studies were conducted to determine the feasibility of the flame emission technique for the monitoring of oil in water samples. The technique is useful for the detection of high vapor pressure oils; however, the lower vapor pressure materials w...

1974-01-01

396

Effect of whey protein agglomeration on spray dried microcapsules containing Saccharomyces boulardii.  

PubMed

This work investigates the effect of whey protein agglomeration on the survivability of Saccharomyces boulardii within spray dried microcapsules. It attempts to go beyond phenomenological observations by establishing a relationship between physicochemical characteristics of the polymeric matrix and its effect on probiotic endurance upon spray drying. It is well known that this type of thermal shock has lethal consequences on the yeast cells. To avoid such undesirable outcome, we take advantage of the early agglomeration phenomenon observed for whey protein by adjusting the pH value of preparations close to isoelectric point (pH 4-5). During the subsequent process of spray drying, development of whey protein agglomerates induces formation of an early crust, and the protein in this molten globular state creates a cohesive network encapsulating the yeast cells. It appears that the early crust formation at a given sample pH and temperature regime during spray drying benefits the survivability of S. boulardii within microcapsules. PMID:23870891

Duongthingoc, Diep; George, Paul; Katopo, Lita; Gorczyca, Elizabeth; Kasapis, Stefan

2013-05-09

397

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

398

Mitigation of copper corrosion and agglomeration in APS process water systems.  

SciTech Connect

Copper corrosion has been observed in process water (PW) systems at the Advanced Photon Source (APS) dating to the early postcommissioning phase of the project. In time, copper corrosion products agglomerated significantly in certain preferred locations. Significant agglomerations (or deposits) can occur in copper cooling passages such as magnet conductors and x-ray absorbers having relatively large length-to-diameter ratios and where heat is removed by water cooling. Such agglomerations also occur at restrictions found in noncopper system components such as valve seats, fixed orifices, pump seal faces, etc. Modifications to the APS process water system that significantly reduce the rate of copper corrosion are discussed. These modifications have not prevented corrosion altogether. Other means used to prevent component clogging and malfunction as a result of current copper corrosion rates are listed.

Dortwegt, R.; Putnam, C.; Swetin, E.

2002-10-10

399

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.

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

2010-01-01

400

Cluster agglomeration induced by dust-density waves in complex plasmas.  

PubMed

Experimental results showing the agglomeration of large carbonaceous particles in a dusty plasma are reported. Experiments were performed in a capacitively coupled rf argon plasma. Acetylene was injected to produce dust particles. When a sufficient amount of nanoparticles is present in the cathodic sheath, self-excited dust-density waves occur. The latter ones induce the motion of larger clusters, which vertically oscillate with the displacement of wave fronts. In some cases, the relative velocity of large particles was high enough to overcome the Coulomb repulsion forces, and agglomeration can be observed. The mechanisms underlying this process are discussed. PMID:23368332

Dap, Simon; Lacroix, David; Hugon, Robert; de Poucques, Ludovic; Briancon, Jean-Luc; Bougdira, Jamal

2012-12-10

401

Characterization of local regularity in SAR Imagery by means of multiscale techniques: application to oil spill detection  

Microsoft Academic Search

Thanks to their capability to cover large areas, in all weather conditions, during the day as well as during the night, spaceborne Synthetic Aperture Radar (SAR) techniques constitute an extremely promising alternative to traditional surveillance methods. Nevertheless, in order to assure further usability of SAR images, specific data mining tools are still to be developed to provide an efficient automatic

M. Tello; C. Lopez-Martinez; J. J. Mallorqui; A. Danisi; G. Di Martino; A. Iodice; G. Ruello; D. Riccio

2007-01-01

402

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

403

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

404

Emission characteristics of organic and heavy metal pollutants in fluidized bed incineration during the agglomeration/defluidization process  

SciTech Connect

The accumulation of adhesive materials may generate agglomerates during incineration. These agglomerates affect fluidization behavior and cause the formation of secondary pollutants. However, the impact of agglomeration on the emission of organics and heavy metals has seldom been investigated. Accordingly, this work focuses on the preparation of different synthetic wastes to simulate the generation of agglomerates, as well as the effects of various alkali metals, alkaline earth metals, and operating temperatures on the formation of pollutants. The experimental results indicate that defluidization time declines as the concentration of sodium increases, and that alkaline earth metals (Mg and Ca) inhibit agglomeration. Concentrations of organic pollutants gradually increase with operating time, indicating that the size of the agglomerate gradually increases, reducing the quality of fluidization and the efficiency of combustion. After defluidization, the temperature on the surface of the sand bed increases, thereby reducing the concentrations of organics, but it remains higher than that of blank operation (without Na addition). Furthermore, concentrations of three volatile metals (Cd, Pb, Cr) follow similar trends with operating time. Independent of whether the agglomerate is formed, the concentrations of emitted heavy metals are similar. After defluidization, the emitted concentration increases, because the system is transformed to the phase of the fixed bed. The abundant silica sand does not capture the heavy metals released from waste combustion. The increasing temperature of the surface of the sand bed significantly enhances the emission of heavy metals. Accordingly, the emitted organic and heavy metal pollutants behave differently during agglomeration and defluidization.

Lin, Chiou-Liang; Wey, Ming-Yen; Yu, Wu-Jung [Department of Environmental Engineering, National Chung-Hsing University, Taichung 402, Taiwan (ROC)

2005-11-01

405

The Hamadya bomb-rich agglomerate: a case study of explosive Pliocene volcanism in the Jordan Valley, Israel  

Microsoft Academic Search

A pyroclastic deposit rich in basaltic bombs, lapilli and scoria is exposed near Hamadya along the western margin of the Jordan Rift Valley, Israel. The deposit is a basaltic agglomerate interlayered with basalt flows of Pliocene age. The agglomerate consists of bombs (some of them 50–70 cm in length), juvenile fragments of lapilli-sized scoriaceous porphyritic basalt and scoria weakly cemented

Shimon Ilani; Sergiu Peltz

1997-01-01

406

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

Microsoft Academic Search

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

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

2005-01-01

407

Numerical study of the effects of particle size and polydispersity on the agglomerate dispersion in a cyclonic flow  

Microsoft Academic Search

This paper presents an investigation of powder dispersion based on a combined computational fluid dynamics (CFD) and discrete element method (DEM) approach. Agglomerates of different particle sizes and polydispersities are dispersed in a cyclonic flow at different flow velocities. The analysis of flow field and agglomerate properties indicates that the dispersion is governed by two competitive interactions, i.e. particle–particle cohesion

Z. B. Tong; R. Y. Yang; K. W. Chu; A. B. Yu; S. Adi; H. K. Chan

2010-01-01

408

A rapid and facile signal enhancement method for microcantilever-based immunoassays using the agglomeration of ferromagnetic nanoparticles.  

PubMed

A rapid and facile signal enhancement method for detecting alpha-fetoprotein (AFP) was developed using the magnetic agglomeration of ferromagnetic nanoparticles and microcantilever sensors. The resonance frequency and deflection of the cantilevers were found to be more than 10-fold greater than that before physical agglomeration of the free nanoparticles around the magnetized nanoparticles. PMID:22691975

Lee, Dongkyu; Kwon, Donghoon; Ko, Wooree; Joo, Jinmyoung; Seo, Hyejung; Lee, Soo Suk; Jeon, Sangmin

2012-06-13

409

Improved techniques for fluid diversion in oil recovery. Quarterly technical progress report, October 1, 1993--December 31, 1993  

SciTech Connect

This three-year project has two general objectives. The first objective is to compare the effectiveness of gels in fluid diversion with those of other types of processes. Several different types of fluid-diversion processes will be compared, including those using gels, foams, emulsions, and particulates. The ultimate goals of these comparisons are 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 will be performed to assess where the various diverting agents will be most effective (e.g., in fractured vs. unfractured wells, deep vs. near-wellbore applications, reservoirs with vs. without crossflow, or injection wells vs. production wells). Experiments will be performed to verify which materials are the most effective in entering and blocking high-permeability zones. Another objective of the project is to identify the mechanisms by which materials (particularly gels) selectively reduce permeability to water more than to oil. In addition to establishing why this occurs, our research will attempt to identify materials and conditions that maximize this phenomenon.

Seright, R.S.

1994-01-01

410

Improved techniques for fluid diversion in oil recovery. Quarterly technical progress report, January 1, 1994--March 31, 1994  

SciTech Connect

This three-year project has two general objectives. The first objective is to compare the effectiveness of gels in fluid diversion with those of other types of processes. Several different types of fluid-diversion processes will be compared, including those using gels, foams, emulsions, and particulates. The ultimate goals of these comparisons are 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 will be performed to assess where the various diverting agents will be most effective (e.g., in fractured vs. unfractured wells, deep vs. near-wellbore applications, reservoirs with vs. without crossflow, or injection wells vs. production wells). Experiments will be performed to verify which materials are the most effective in entering and blocking high-permeability zones. Another objective of the project is to identify the mechanisms by which materials (particularly gels) selectively reduce permeability to water more than to oil. In addition to establishing why this occurs, our research will attempt to identify materials and conditions that maximize this phenomenon.

Seright, R.S.

1994-04-01

411

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

412

Applications of Agglomerate Testing to Problems in Water Resources Management.  

National Technical Information Service (NTIS)

Studies were conducted to evaluate several coagulation testing techniques. Of those considered, the jar-test was the most useful for evaluating the settleability of flocculated suspensions, and the membrane refiltration test for evaluating filtrability of...

R. K. Ham K. B. Gupta

1972-01-01

413

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

414

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

415

Production of instant soymilk powders by ultrafiltration, spray drying and fluidized bed agglomeration  

Microsoft Academic Search

Production of instant soymilk powders was completed in three stages – ultrafiltration, spray drying, and fluidized bed agglomeration. Ultrafiltration increased total solids, protein, and fat contents, but decreased carbohydrate and ash contents of soymilk, leading to an increase in particle size, wettability, and dispersibility of the resultant spray-dried powders. However, all the spray-dried soymilk powders were very small (<25?m) and

Nakarin Jinapong; Manop Suphantharika; Pimon Jamnong

2008-01-01

416

Dielectric properties of epoxy\\/alumina nanocomposite influenced by control of micrometric agglomerates  

Microsoft Academic Search

Introduction of metal oxide nanoparticles to polymer material is known to have unique dielectric behavior and significant advantages in electrical insulation performance in power apparatus. This paper presents an attempt to clarify the influence of dispersibility of nanoparticles, especially focusing on agglomerates, on dielectric properties of a nanocomposite system by changing particle dispersion processes. Experiments were carried out in epoxy\\/alumina

Muneaki Kurimoto; Hitoshi Okubo; Katsumi Kato; Masahiro Hanai; Yoshikazu Hoshina; Masafumi Takei; Naoki Hayakawa

2010-01-01

417

Urban Amenities or Agglomeration Economies? Locational Behaviour and Entrepreneurial Success of Dutch Fashion Designers  

Microsoft Academic Search

Urban economic growth and industrial clustering is traditionally explained by Marshallian agglomeration economies benefiting co-located firms. The focus on firms rather than people has been challenged by Florida arguing that urban amenities and a tolerant climate attract creative people, and the firms they work for, to certain cities. We analyse to what extent these two mechanisms affect the locational behaviour

Rik Wenting; Oedzge Atzema; Koen Frenken

2008-01-01

418

Urban Amenities and Agglomeration Economies? The Locational Behaviour and Economic Success of Dutch Fashion Design Entrepreneurs  

Microsoft Academic Search

The spatial clustering of industries is traditionally explained by agglomeration economies benefiting co-located firms. The focus on firms rather than people has been challenged by Florida arguing that urban amenities attract creative people to certain cities. On the basis of a questionnaire, an analysis is made of the extent to which these two mechanisms affect the locational behaviour of Dutch

Rik Wenting; Oedzge Atzema; Koen Frenken

2011-01-01

419

Are carbon nanotube effects on green algae caused by shading and agglomeration?  

PubMed

Due to growing production, carbon nanotubes (CNT) may soon be found in a broad range of products and thus in the environment. In this work, an algal growth test was developed to determine effects of pristine and oxidized CNT on the green algae Chlorella vulgaris and Pseudokirchneriella subcapitata. CNT suspensions were prepared in algal test medium and characterized taking into account the suspension age, the reduced light transmittance of nanoparticle suspensions defined as shading of CNT and quantified by UV/vis spectroscopy, and the agglomeration of the CNT and of the algal cells. Growth inhibition and photosynthetic activity were investigated as end points. Growth of C. vulgaris was inhibited with effect concentrations of 50% (EC(50)) values of 1.8 mg CNT/L and of 24 mg CNT/L in well dispersed and in agglomerated suspensions, respectively, and 20 mg CNT/L and 36 mg CNT/L for P. subcapitata, respectively. However, the photosynthetic activity was not affected. Growth inhibition was highly correlated with the shading of CNT and the agglomeration of algal cells. This suggests that the reduced algal growth might be caused mainly by indirect effects, i.e. by reduced availability of light and different growth conditions caused by the locally elevated algal concentration inside of CNT agglomerates. PMID:21702508

Schwab, Fabienne; Bucheli, Thomas D; Lukhele, Lungile P; Magrez, Arnaud; Nowack, Bernd; Sigg, Laura; Knauer, Katja

2011-06-27

420

Agglomeration of pharmaceutical, detergent, chemical and food powders — Similarities and differences of materials and processes  

Microsoft Academic Search

Product developers tend to make a distinction between different types of agglomerated powders depending on whether they are produced by the pharmaceutical, detergent, chemical or food industry. This is perfectly valid for the hygiene, quality, safety or economical aspects of processes and products. However, from a process engineering point of view a different classification is needed in order to identify

St. Palzer

2011-01-01

421

A PROM element based on salicide agglomeration of poly fuses in a CMOS logic process  

Microsoft Academic Search

A novel programmable element has been developed and evaluated for state of the art CMOS processes. This element is based on agglomeration of the Ti-silicide layer on top of poly fuses. Various aspects of this programmable device including characterization and optimization of physical and electrical aspects of the element, programming yield, and reliability have been studied. Development of a novel

Mohsen Alavi; Mark Bohr; Jeff Hicks; Martin Denham; Allen Cassens; Dave Douglas; Min-Chun Tsai

1997-01-01

422

Firm exit and spatial agglomeration. Evidence on the resilience of Italian provinces  

Microsoft Academic Search

The paper investigates the effect of spatial agglomeration on firm exit. In particular, the role of specialization and local variety in production is addressed. The extent to which industrial clusters can be actually retained industrial districts is also considered. Empirical evidence is provided for a large panel of Italian provinces and manufacturing sectors over the period 1995-2007. Urbanization economies significantly

Giulio Cainelli; Sandro Montresor; Giuseppe Vittucci Marzetti

2010-01-01

423

Colloidal agglomerates in tank sludge: Impact on waste processing. 1997 annual progress report  

SciTech Connect

'Disposal of millions of gallons of existing radioactive wastes is a major remediation problem for the Department of Energy (DOE). Although radionuclides are the most hazardous waste con- stituents. the components of greatest concern from a waste processing standpoint are insoluble sludges consisting of submicron colloidal particles. Depending on processing conditions, these colloidal particles can form agglomerate networks that could clog transfer lines or interfere with solid-liquid separations such as settle-decant operations. Under different conditions, the particles can be dispersed to form very fine suspended particles that will not create sediment in settle- decant steps and that can foul and contaminate downstream treatment components including ion exchangers or filtrations systems. Given the wide range of tank chemistries present at Hanford and other DOE sites, it is impractical to measure the properties of all potential processing conditions to design effective treatment procedures. Instead. a framework needs to be established to allow sludge property trends to be predicted on a sound scientific basis. The scientific principles of greatest utility in characterizing, understanding, and controlling the physical properties of sludge fall in the realm of colloid chemistry. The objectives of this work are to accomplish the following: understand the factors controlling the nature and extent of colloidal agglomeration under expected waste processing conditions determine how agglomeration phenomena influence physical properties relevant to waste processing including rheology, sedimentation. and filtration develop strategies for optimizing processing conditions via control of agglomeration phenomena.'

Virden, J.W.

1997-06-01

424

A novel recovery technology of trace precious metals from waste water by combining agglomeration and adsorption  

Microsoft Academic Search

A novel and efficient technology for separating and recovering precious metals from waste water containing traces of Pd and Ag was studied by the combination of agglomeration and adsorption. The recovery process and the impacts of operating conditions such as pH value of waste water, adsorption time, additive quantity of the flocculant and adsorbent on the recovery efficiency were studied

Hua-sheng ZOU; Zhu-qiang CHU; Gang LIN

2007-01-01

425

Evaluation of melt agglomeration properties of polyethylene glycols using a mixer torque rheometer.  

PubMed

Lactose was melt agglomerated in a mixer torque rheometer with polyethylene glycol (PEG) 2000, 3000, 6000, 8000, 10 000, or 20 000 as meltable binder. A longer massing time caused an increase in mean torque until a maximum value after which the torque decreased. A smaller particle size of the PEG gave rise to a faster initial rise in mean torque. The higher viscosity of the PEG 20 000 resulted in a higher mean torque, whereas no clear difference in mean torque was obtained with the other PEGs. The binder concentration could be varied within a rather wide range without causing overwetting, the range being wider with PEG 3000 than with PEG 20 000. The mean torque values obtained were found to be related to the liquid saturation of the agglomerates. The reproducibility of the experiments was found to be very dependent on the experimental conditions, the highest binder viscosities and binder concentrations giving rise to a poor reproducibility. The results were compared with a few melt agglomeration experiments with PEG 3000 in a high shear mixer. The mixer torque rheometer was found not to be suitable for predicting melt agglomeration properties in the high shear mixer because of a marked difference in the shear forces in the two mixers. PMID:10361166

Johansen, A; Schaefer, T; Kristensen, H G

1999-06-25

426

A Note on the Growth of Primary Particles in Agglomerate Structures by Coalescence  

Microsoft Academic Search

Aerosol particles at high concentrations grow by collisions and coalescence. If coalescence is faster, particles remain individual and spherical, and primary particle growth is determined by the collision rate. When collisions are faster, dendritic agglomerates consisting of a large number of primary particles form. Primary particle growth is then determined by the coalescence rate. In this Note a model is

Kari E. J. Lehtinen; Robert S. Windeler; Sheldon K. Friedlander

1996-01-01

427

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

428

DEVELOPMENT PATTERNS IN CANADA'S LARGEST URBAN AGGLOMERATION: FOUR DECADES OF EVOLUTION  

Microsoft Academic Search

The city of Toronto, Ontario and its surrounding regions constitute the largest urban agglomeration in Canada and the fifth largest in North America. Urban development within this area is an impor- tant planning and environmental issue. Landsat images from 1972 to 2004 (a total of 10 scenes covering a period of 32 years) were used in this research that cover

K. Wayne Forsythe; Paul Du

429

Cultural and economic complementarities of spatial agglomeration in the British television broadcasting industry: some explorations  

Microsoft Academic Search

This paper considers the processes supporting agglomeration in the British television broadcasting industry. It compares and contrasts the insights offered by the cultural turn in geography and more conventionally economic approaches. It finds that culture and institutions are fundamental to the constitution of production and exchange relationships and also that they solve fundamental economic problems of coordinating resources under conditions

Gary A S Cook; Naresh R Pandit; Jonathan V Beaverstock

2011-01-01

430

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

431

Reduced bed agglomeration by co-combustion biomass with peat fuels in a fluidized bed  

Microsoft Academic Search

Fluidized bed combustion is an energy conversion technology that is very suitable for biomass combustion because of its fuel flexibility and low process temperatures. However, agglomeration of bed material may cause severe operating problems. To prevent or at least reduce this, peat has been suggested as an additive to the main fuels. Nevertheless, the characteristics of peat fuels vary and

Karin Lundholm; Anders Nordin; Marcus Oehman; Dan Bostroem

2005-01-01

432

Final report on agglomerate column flotation for cleaning and desulfurization of Ohio coal fines  

Microsoft Academic Search

The objective of this research program was investigate the feasibility of cleaning and desulfurization of Ohio coal by an agglomerate column flotation process, which integrates selective flocculation with conventional column flotation. It was concluded earlier on in the program that the conventional design of flotation column was not particularly efficient for pyrite rejection. A novel design for flotation column system

Y. A. Attia; M. El Zeky; Mulong Yu

1990-01-01

433

Characterisation of the de-agglomeration effects of bovine serum albumin on nanoparticles in aqueous suspension.  

PubMed

This paper describes the use of nanoparticle characterisation tools to evaluate the interaction between bovine serum albumin (BSA) and dispersed nanoparticles in aqueous media. Dynamic light scattering, zeta-potential measurements and scanning electron microscopy were used to probe the state of zinc oxide (ZnO) and titanium dioxide (TiO(2)) nanoparticles in the presence of various concentrations of BSA, throughout a three-day period. BSA was shown to adhere to ZnO but not to TiO(2). The adsorption of BSA led to subsequent de-agglomeration of the sub-micron ZnO clusters into smaller fragments, even breaking them up into individual isolated nanoparticles. We propose that certain factors, such as adsorption kinetics of BSA on to the surface of ZnO, as well as the initial agglomerated state of the ZnO, prior to BSA addition, are responsible for promoting the de-agglomeration process. Hence, in the case of TiO(2) we see no de-agglomeration because: (a) the nanoparticles are more highly agglomerated to begin with and (b) BSA does not adsorb effectively on the surface of the nanoparticles. The zeta-potential results show that, for either ZnO or TiO(2), the presence of BSA resulted in enhanced stability. In the case of ZnO, the enhanced stability is limited to BSA concentrations below 0.5 wt.%. Steric and electrostatic repulsion are thought to be responsible for improved stability of the dispersion. PMID:19775871

Tantra, Ratna; Tompkins, Jordan; Quincey, Paul

2009-09-06

434

Pilot plant testing of IGT`s two-stage fluidized-bed/cyclonic agglomerating combustor  

SciTech Connect

The Institute of Gas Technology (IGT) is conducting a multi-year experimental program to develop and test, through pilot-scale operation, IGT`s two-stage fluidized-bed/cyclonic agglomerating combustor (AGGCOM). The AGGCOM process is based on combining the fluidized-bed agglomeration and gasification technology with the cyclonic combustion technology, both of which have been developed at IGT over many years. AGGCOM is a unique and extremely flexible combustor that can operate over a wide range of conditions in the fluidized-bed first stage from low temperature (desorption) to high temperature (agglomeration), including gasification of high-energy-content wastes. The ACCCOM combustor can easily and efficiently destroy solid, liquid, and gaseous organic wastes, while isolating solid inorganic contaminants within an essentially non-leachable glassy matrix, suitable for disposal in ordinary landfills. Fines elutriated from the first stage are captured by a high-efficiency cyclone and returned to the fluidized bed for ultimate incorporation into the agglomerates. Intense mixing in the second-stage cyclonic combustor ensures high destruction and removal efficiencies (DRE) for organic compounds that may be present in the feed material. This paper presents an overview of the experimental development of the AGGCOM process and progress made to date in designing, constructing, and operating the 6-ton/day AGGCOM pilot plant. Results of the bench-scale tests conducted to determine the operating conditions necessary to agglomerate a soil were presented at the 1991 Incineration Conference. On-site construction of the AGGCOM pilot plant was initiated in August 1992 and completed at the end of March 1993, with shakedown testing following immediately thereafter. The initial tests in the AGGCOM pilot plant will focus on the integrated operation of both stages of the combustor and will be conducted with ``clean`` topsoil.

Rehmat, A.; Mensinger, M.C. [Institute of Gas Technology, Chicago, IL (United States); Richardson, T.L. [Environmental Protection Agency, Cincinnati, OH (United States)

1993-12-31

435

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

436

Sonic Enhanced Ash Agglomeration and Sulfur Capture. Technical progress report, July 1993--September 1993  

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 ``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.

Not Available

1993-12-31

437

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

438

Microbial Enhanced Oil Recovery (MEOR)  

Microsoft Academic Search

Microbial enhanced oil recovery (MEOR) represents the use of microorganisms to extract the remaining oil from reservoirs. This technique has the potential to be cost-efficient in the extraction of oil remained trapped in capillary pores of the formation rock or in areas not swept by the classical or modern enhanced oil recovery (EOR) methods, such as combustion, steams, miscible displacement,

I. Lazar; I. G. Petrisor; T. F. Yen

2007-01-01

439

Influence of temperature and gas composition on the sintering of Estonian oil share ash.  

National Technical Information Service (NTIS)

In this work it is studied how the oil shale ash will behave in typical fluidized bed conditions, with a focus on bed agglomeration and fireside deposit. We wanted especially to study the effects of different gas atmospheres and temperatures on the ash sa...

T. Parve B. J. Skrifvars A. Ots M. Hupa

1994-01-01

440

Toxicity study of the oil dispersant Corexit 9527 on Macrobrachium rosenbergii (de Man) egg hatchability by using a flow-through bioassay technique.  

PubMed

The effect of the oil-spill dispersant Corexit 9527 on egg-hatching rate of Macrobrachium rosenbergii (de Man) was studied by using an innovated flow-through bioassay technique. This bioassay method relies on the fact that M. rosenbergii fertilized eggs when detached from the mother prawn were able to hatch artificially. The flow-through system generated a stable and good water quality environment for hatching the eggs successfully. The Corexit 9527 had a pronounced effect on hatching rate of the M. rosenbergii eggs. In the control, the hatching rate of the eggs was 95.55% +/- 1.74%. However, it was reduced drastically with increasing concentrations of Corexit 9527. A 100% inhibition of egg hatchability was found when the level of Corexit 9527 was higher than 250 mg litre(-1). The EC(50) and the EC(95) values estimated by the probit method were 80.4 +/- 5.5 mg litre(-1) and 193.5 +/- 39.9 mg litre(-1) respectively (P = 0.05). The recommended safety level of Corexit 9527 for M. rosenbergii in Malaysian estuarine waters is below 40 mg litre(-1). PMID:15091547

Law, A T

1995-01-01

441

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

442

Properties and formation mechanism of tetrainterstitial agglomerates in hydrogen-doped silicon  

SciTech Connect

For the tetrainterstitial agglomerate (I{sub 4}), four additional silicon (Si) atoms are incorporated in an ordinary unit cell of Si lattice in such a manner that all atoms are four-coordinated and angles between bonds are not disturbed significantly. Microstructure, electrical properties, and formation mechanism of I{sub 4} in Si were inferred from the investigation of associated electron spin resonance (ESR) spectra in various samples under various experimental conditions. It was found that the B3 ESR spectrum is related to a positive charge state of I{sub 4} and the NL51 spectrum is related to the excitonic state of the neutral defect. In Si samples predoped with hydrogen, formation of tetrainterstitial agglomerates after electron-irradiation and annealing is associated with various reactions of hydrogen with intrinsic defects.

Mchedlidze, Teimuraz; Suesawa, Masashi [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

2004-11-15

443

Multivariate analysis applied to agglomerated macrobenthic data from an unpolluted estuary.  

PubMed

We agglomerated species into higher taxonomic aggregations and functional groups to analyse environmental gradients in an unpolluted estuary. We then applied non-metric Multidimensional Scaling and Redundancy Analysis (RDA) for ordination of the agglomerated data matrices. The correlation between the ordinations produced by both methods was generally high. However, the performance of the RDA models depended on the data matrix used to fit the model. As a result, salinity and total nitrogen were only found significant when aggregated data matrices were used rather than species data matrix. We used the results to select a RDA model that explained a higher percentage of variance in the species data set than the parsimonious model. We conclude that the use of aggregated matrices may be considered complementary to the use of species data to obtain a broader insight into the distribution of macrobenthic assemblages in relation to environmental gradients. PMID:23684322

Conde, Anxo; Novais, Júlio M; Domínguez, Jorge

2013-05-04

444

Transfer-free graphene synthesis on insulating substrates via agglomeration phenomena of catalytic nickel films  

NASA Astrophysics Data System (ADS)

Graphene layers were synthesized by annealing amorphous carbon (a-C) thin films on Ni/SiO2/Si(111) substrates grown using pulse arc plasma deposition. Although the graphene layers were formed by catalytic reaction between a-C films and Ni metals, they were observed to be directly on the insulating SiO2/Si substrates with island-shaped metallic particles. These particles presumably resulted from agglomeration phenomena of thin Ni films at a high temperature. We speculated that the agglomeration phenomena allowed the graphene formation on SiO2/Si substrates. It was also confirmed that the particle size and graphene layer thickness depend on the starting Ni thickness.

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

2013-08-01

445

The Agglomeration in the Fluidized Bed Boiler During the Co-Combustion of Biomass with Peat  

NASA Astrophysics Data System (ADS)

The formation of bed material coatings during the co-combustion of peat and biomass is caused by iron, calcium, aluminum and silicon. No signs of sodium or calcium sulfates were observed in bed material samples. Sulfates were observed in fly ash samples, when the amount of wood was 55% of the fuel mixture. Thus the bed material agglomeration during peat and biomass co-combustion is due to the partial melting of aluminosilicates, rather than the formation of low melting salts. Iron is found from the bed material coatings and may act as a flux in the melting processes of the silicates. When the agglomeration progresses, the coated sand particles are molten on the surface as seen from the increased amounts of potassium, sodium and calcium. The role of iron is not so significant in the adhesive material.

Heikkinen, Ritva E. A.; Virtanen, Mika E.; Patrikainen, H. Tapio; Laitinen, Risto S.

446

Observation of superparamagnetism to flux closure behaviour in ZnO nanoparticle agglomerates.  

PubMed

In this paper we have tried to understand the nature of magnetism in ZnO nanoparticle samples with an intrinsic 50 ppm trace of Fe impurity. When the samples are annealed we observe formation of nanoparticle agglomerates and the size increases with annealing temperature. When the sample is annealed at 600 °C we observe superparamagnetic behaviour, and the magnetic hysteresis along with the coercive field below the blocking temperature is almost independent of the cooling field. When the sample is annealed at 900 °C we observe reduction of saturation magnetization but the magnetic hysteresis and the coercive field are now dependent on the cooling field, indicating magnetic correlation and ordering within the agglomerated nanograins. We propose a simple model that explains the reduction of magnetization as being due to a vortex-state-like flux closure formation. PMID:22892994

Ghosh, B; Sardar, M; Lahiri, S; Banerjee, S

2012-08-15

447

Relationships Between in Vivo Survival and (1) Density Distribution, (2) Osmotic Fragility of Previously Frozen, Autologous, Agglomerated, Deglycerolized Erythrocytes.  

National Technical Information Service (NTIS)

In 39 autotransfusion, significant correlations were observed between (1) density distribution and (2) osmotic fragility and 24-hour posttransfusion survival of chromium-labeled human erythrocytes preserved with glycerol using a slow-freeze agglomeration ...

C. R. Valeri L. E. McCallum D. Danon

1966-01-01

448

Measurement and Modeling of Light Extinction and Angular Scattering by Flame Soot Agglomerates.  

NASA Astrophysics Data System (ADS)

Both optical diagnostics and radiative properties of soot particles depend on refractive indices, size distribution and agglomeration morphology. It is found that agglomeration has the significant effect on scattering, but only a minimal effect on absorption for small agglomerates. An experimental setup was designed and fabricated so that laser light scattering/extinction measurement data on fuel-rich laminar premixed propane/oxygen flame using a flat flame burner could be studied as a function of the height above the burner and multiple scattering angles. Using an improved experimental arrangement that allowed for the first time to our knowledge angular scattering data at small angles (theta < 20^circ), the angular scattering pattern was investigated. In addition, the existing treatment of aggregates is based on intrinsic properties, namely, the primary particle size and number of spheres in an aggregate rather than on equivalent spheres. The full angular scattering pattern and dissymmetry ratio demonstrated that there exists a zone of Rayleigh scattering (near 5mm height above the burner for the present study flame conditions), and the agglomeration increased outside of this zone. The results for the depolarization ratio demonstrated that the soot particles for the richer flame became spherical asymmetric earlier than for the leaner flame. The experimental data of fuel-rich laminar premixed propane/oxygen flame were interpreted using the fractal theory, for first time in the present study, whereas the ethene diffusion flame had been used for most of the previous work. Even though the fractal theory is the best model for the soot aggregates so far, it does not adequately fit the present data. The quantities determined by the fractal theory should show dependency on the complex refractive indices and the primary particle sizes of the primary soot particles.

Shim, Kyoung-Hoon