PWR steam generator chemical cleaning. Phase I: solvent and process development. Volume II

International Nuclear Information System (INIS)

Larrick, A.P.; Paasch, R.A.; Hall, T.M.; Schneidmiller, D.

1979-01-01

A program to demonstrate chemical cleaning methods for removing magnetite corrosion products from the annuli between steam generator tubes and the tube support plates in vertical U-tube steam generators is described. These corrosion products have caused steam generator tube ''denting'' and in some cases have caused tube failures and support plate cracking in several PWR generating plants. Laboratory studies were performed to develop a chemical cleaning solvent and application process for demonstration cleaning of the Indian Point Unit 2 steam generators. The chemical cleaning solvent and application process were successfully pilot-tested by cleaning the secondary side of one of the Indian Point Unit 1 steam generators. Although the Indian Point Unit 1 steam generators do not have a tube denting problem, the pilot test provided for testing of the solvent and process using much of the same equipment and facilities that would be used for the Indian Point Unit 2 demonstration cleaning. The chemical solvent selected for the pilot test was an inhibited 3% citric acid-3% ascorbic acid solution. The application process, injection into the steam generator through the boiler blowdown system and agitation by nitrogen sparging, was tested in a nuclear environment and with corrosion products formed during years of steam generator operation at power. The test demonstrated that the magnetite corrosion products in simulated tube-to-tube support plate annuli can be removed by chemical cleaning; that corrosion resulting from the cleaning is not excessive; and that steam generator cleaning can be accomplished with acceptable levels of radiation exposure to personnel

Replacement of HCFC-225 Solvent for Cleaning NASA Propulsion Oxygen Systems

Science.gov (United States)

Mitchell, Mark A.; Lowrey, Nikki M.

2015-01-01

Since the 1990's, when the Class I Ozone Depleting Substance (ODS) chlorofluorocarbon-113 (CFC-113) was banned, NASA's rocket propulsion test facilities at Marshall Space Flight Center (MSFC) and Stennis Space Center (SSC) have relied upon hydrochlorofluorocarbon-225 (HCFC-225) to safely clean and verify the cleanliness of large scale propulsion oxygen systems. Effective January 1, 2015, the production, import, export, and new use of HCFC-225, a Class II ODS, was prohibited by the Clean Air Act. In 2012 through 2014, leveraging resources from both the NASA Rocket Propulsion Test Program and the Defense Logistics Agency - Aviation Hazardous Minimization and Green Products Branch, test labs at MSFC, SSC, and Johnson Space Center's White Sands Test Facility (WSTF) collaborated to seek out, test, and qualify a replacement for HCFC-225 that is both an effective cleaner and safe for use with oxygen systems. Candidate solvents were selected and a test plan was developed following the guidelines of ASTM G127, Standard Guide for the Selection of Cleaning Agents for Oxygen Systems. Solvents were evaluated for materials compatibility, oxygen compatibility, cleaning effectiveness, and suitability for use in cleanliness verification and field cleaning operations. Two solvents were determined to be acceptable for cleaning oxygen systems and one was chosen for implementation at NASA's rocket propulsion test facilities. The test program and results are summarized. This project also demonstrated the benefits of cross-agency collaboration in a time of limited resources.

Cleaning of biomaterial surfaces: protein removal by different solvents.

Science.gov (United States)

Kratz, Fabian; Grass, Simone; Umanskaya, Natalia; Scheibe, Christian; Müller-Renno, Christine; Davoudi, Neda; Hannig, Matthias; Ziegler, Christiane

2015-04-01

The removal of biofilms or protein films from biomaterials is still a challenging task. In particular, for research investigations on real (applied) surfaces the reuse of samples is of high importance, because reuse allows the comparison of the same sample in different experiments. The aim of the present study was to evaluate the cleaning efficiency of different solvents (SDS, water, acetone, isopropanol, RIPA-buffer and Tween-20) on five different biomaterials (titanium, gold, PMMA (no acetone used), ceramic, and PTFE) with different wettability which were covered by layers of two different adsorbed proteins (BSA and lysozyme). The presence of a protein film after adsorption was confirmed by transmission electron microscopy (TEM). After treatment of the surfaces with the different solvents, the residual proteins on the surface were determined by BCA-assay (bicinchoninic acid assay). Data of the present study indicate that SDS is an effective solvent, but for several protein-substrate combinations it does not show the cleaning efficiency often mentioned in literature. RIPA-buffer and Tween-20 were more effective. They showed very low residual protein amounts after cleaning on all examined material surfaces and for both proteins, however, with small differences for the respective substrate-protein combinations. RIPA-buffer in combination with ultrasonication completely removed the protein layer as confirmed by TEM. Copyright © 2015 Elsevier B.V. All rights reserved.

Background Noise Contributes to Organic Solvent Induced Brain Dysfunction

Directory of Open Access Journals (Sweden)

O’neil W. Guthrie

2016-01-01

Full Text Available Occupational exposure to complex blends of organic solvents is believed to alter brain functions among workers. However, work environments that contain organic solvents are also polluted with background noise which raises the issue of whether or not the noise contributed to brain alterations. The purpose of the current study was to determine whether or not repeated exposure to low intensity noise with and without exposure to a complex blend of organic solvents would alter brain activity. Female Fischer344 rats served as subjects in these experiments. Asynchronous volume conductance between the midbrain and cortex was evaluated with a slow vertex recording technique. Subtoxic solvent exposure, by itself, had no statistically significant effects. However, background noise significantly suppressed brain activity and this suppression was exacerbated with solvent exposure. Furthermore, combined exposure produced significantly slow neurotransmission. These abnormal neurophysiologic findings occurred in the absence of hearing loss and detectable damage to sensory cells. The observations from the current experiment raise concern for all occupations where workers are repeatedly exposed to background noise or noise combined with organic solvents. Noise levels and solvent concentrations that are currently considered safe may not actually be safe and existing safety regulations have failed to recognize the neurotoxic potential of combined exposures.

Background Noise Contributes to Organic Solvent Induced Brain Dysfunction

Science.gov (United States)

Guthrie, O'neil W.; Wong, Brian A.; McInturf, Shawn M.; Reboulet, James E.; Ortiz, Pedro A.; Mattie, David R.

2016-01-01

Occupational exposure to complex blends of organic solvents is believed to alter brain functions among workers. However, work environments that contain organic solvents are also polluted with background noise which raises the issue of whether or not the noise contributed to brain alterations. The purpose of the current study was to determine whether or not repeated exposure to low intensity noise with and without exposure to a complex blend of organic solvents would alter brain activity. Female Fischer344 rats served as subjects in these experiments. Asynchronous volume conductance between the midbrain and cortex was evaluated with a slow vertex recording technique. Subtoxic solvent exposure, by itself, had no statistically significant effects. However, background noise significantly suppressed brain activity and this suppression was exacerbated with solvent exposure. Furthermore, combined exposure produced significantly slow neurotransmission. These abnormal neurophysiologic findings occurred in the absence of hearing loss and detectable damage to sensory cells. The observations from the current experiment raise concern for all occupations where workers are repeatedly exposed to background noise or noise combined with organic solvents. Noise levels and solvent concentrations that are currently considered safe may not actually be safe and existing safety regulations have failed to recognize the neurotoxic potential of combined exposures. PMID:26885406

Background Noise Contributes to Organic Solvent Induced Brain Dysfunction.

Science.gov (United States)

Guthrie, O'neil W; Wong, Brian A; McInturf, Shawn M; Reboulet, James E; Ortiz, Pedro A; Mattie, David R

2016-01-01

Occupational exposure to complex blends of organic solvents is believed to alter brain functions among workers. However, work environments that contain organic solvents are also polluted with background noise which raises the issue of whether or not the noise contributed to brain alterations. The purpose of the current study was to determine whether or not repeated exposure to low intensity noise with and without exposure to a complex blend of organic solvents would alter brain activity. Female Fischer344 rats served as subjects in these experiments. Asynchronous volume conductance between the midbrain and cortex was evaluated with a slow vertex recording technique. Subtoxic solvent exposure, by itself, had no statistically significant effects. However, background noise significantly suppressed brain activity and this suppression was exacerbated with solvent exposure. Furthermore, combined exposure produced significantly slow neurotransmission. These abnormal neurophysiologic findings occurred in the absence of hearing loss and detectable damage to sensory cells. The observations from the current experiment raise concern for all occupations where workers are repeatedly exposed to background noise or noise combined with organic solvents. Noise levels and solvent concentrations that are currently considered safe may not actually be safe and existing safety regulations have failed to recognize the neurotoxic potential of combined exposures.

Accelerated solvent extraction method with one-step clean-up for hydrocarbons in soil

International Nuclear Information System (INIS)

Nurul Huda Mamat Ghani; Norashikin Sain; Rozita Osman; Zuraidah Abdullah Munir

2007-01-01

The application of accelerated solvent extraction (ASE) using hexane combined with neutral silica gel and sulfuric acid/ silica gel (SA/ SG) to remove impurities prior to analysis by gas chromatograph with flame ionization detector (GC-FID) was studied. The efficiency of extraction was evaluated based on the three hydrocarbons; dodecane, tetradecane and pentadecane spiked to soil sample. The effect of ASE operating conditions (extraction temperature, extraction pressure, static time) was evaluated and the optimized condition obtained from the study was extraction temperature of 160 degree Celsius, extraction pressure of 2000 psi with 5 minutes static extraction time. The developed ASE with one-step clean-up method was applied in the extraction of hydrocarbons from spiked soil and the amount extracted was comparable to ASE extraction without clean-up step with the advantage of obtaining cleaner extract with reduced interferences. Therefore in the developed method, extraction and clean-up for hydrocarbons in soil can be achieved rapidly and efficiently with reduced solvent usage. (author)

Microwave-assisted clean synthesis of amides via aza-wittig reaction under solvent-free condition

Energy Technology Data Exchange (ETDEWEB)

Sathishkumar, Murugan; Nagarajan, Sangaraiah; Velan, Poovan Shanmuga; Dinesh, Murugan; Ponnuswamy, Alagusundaram [Department of Organic Chemistry, School of Chemistry, Madurai Kamaraj University, Tamilnadu (India)

2011-09-15

A solvent-free microwave-assisted coupling of phosphazenes with acyl chlorides or carboxylic anhydrides in presence of triethylphosphite has been accomplished resulting in a clean synthesis of amides in good yields. Unlike the prevailing time-consuming solution phase methodologies employing chlorinated solvents, benzene (carcinogenic), etc, the present protocol is an eco friendly, rapid and simple approach. (author)

Clean air strategy for Alberta: Background project reports

International Nuclear Information System (INIS)

1991-06-01

As a background to the development of a clean air strategy for Alberta, reports are presented which cover the definition of what clean air is, the applicability of full cost accounting to this strategy, market-based approaches to managing Alberta air emissions, gas and electric utility incentives programs for energy efficiency, energy efficiency legislation in Alberta and other jurisdictions, initiatives which address emissions reduction in the transportation sector, coordination of science and technology relevant to clean air issues, and initiatives in energy and environmental education

Ultrasonic and immersion cleaning: a comparison using aqueous and fluorocarbon solvents

International Nuclear Information System (INIS)

Bond, R.D.; Kearsey, A.

1984-11-01

Decontamination is a necessary process in reducing radiation levels in the working environment in the nuclear industry. Components from active areas which require decontamination for re-use or maintenance operations. In this report, a typical chemical cleaning process using liquid pumping, airagitation and physical movement for agitation is compared with ultrasonic cleaning, now an established cleaning process in many industries. The chosen traditional method is immersion in an agitated solution of warm SDG.3 solution; an established decontaminating reagent. The decontamination effect of this process is compared with the effect of cleaning in an ultrasonic bath containing the same reagent at the same concentration and temperature. Fluorocarbon reagents are of particular interest to the nuclear industry for they offer the ability to clean electrical components without damage, and can clean product contaminated material without the risk of criticality. Such reagents are based on 1,1,2-trichloro, 1,2,2-trifluoroethane and azeotropic mixtures. This reagent and one mixture with 6% methanol were tested under agitation and ultrasonic immersion at the same temperature. Parallel control experiments were conducted using demineralised water as the cleaning media in an agitated bath. SGG3 is a good reagent for general purpose cleaning (it can remove 99% of particulate contamination) using scrubbing, immersion or spraying techniques. There is little evidence to show that ultrasonic cleaning increases its effectiveness. For special purpose fluorocarbon solvents will give satisfactory results when used in an ultrasonic system. (author)

Plasma Cleaning

Science.gov (United States)

Hintze, Paul E.

2016-01-01

NASA's Kennedy Space Center has developed two solvent-free precision cleaning techniques: plasma cleaning and supercritical carbon dioxide (SCCO2), that has equal performance, cost parity, and no environmental liability, as compared to existing solvent cleaning methods.

Solvent substitutes

International Nuclear Information System (INIS)

Evanoff, S.P.

1995-01-01

The environmental and industrial hygiene regulations promulgated since 1980, most notably the Superfund Amendments and Reauthorization Act (SARA), the Hazardous and Solid Waste Amendments to the Resources Conservation and Recovery Act (RCRA), and the Clean Air Act Amendments of 1990, have brought about an increased emphasis on user exposure, hazardous waste generation, and air emissions. As a result, industry is performing a fundamental reassessment of cleaning solvents, processes, and procedures. The more progressive organizations have made their goal the elimination of solvents that may pose significant potential human health and environmental hazards. This chapter discusses solvent cleaning in metal-finishing, metal-manufacturing, and industrial maintenance applications; precision cleaning; and electronics manufacturing. Nonmetallic cleaning, adhesives, coatings, inks, and aerosols also will be addressed, but in a more cursory manner

Cleanup of 7.5% tributyl phosphate/n-paraffin solvent-extraction solvent

International Nuclear Information System (INIS)

Reif, D.J.

1987-02-01

The HM process at the Savannah River Plant uses 7.5% tributyl phosphate in n-paraffin as an extraction solvent. During use, the solvent is altered due to hydrolysis and radiolysis, forming materials which influence product losses, product decontamination, and separation efficiencies. Laboratory studies to improve online solvent cleaning have shown that carbonate washing, although removing residual solvent activity, does not remove binding ligands which hold fission products in the solvent. Treatment of solvent by an alumina adsorption process removes binding ligands and significantly improves recycle solvent performance. Both laboratory work defining a full-scale alumina adsorption process and the use of the process to clean HM process first cycle solvent is discussed

Restoring solvent for nuclear separation processes

International Nuclear Information System (INIS)

Reif, D.J.

1987-01-01

Solvent extraction separation processes are used to recover usable nuclear materials from spent fuels. These processes involve the use of an extractant/diluent (solvent) for separation of the reusable actinides from unwanted fission products. The most widely used processes employ tributyl phosphate as an extractant diluted with a normal-paraffin hydrocarbon. During use, the solvent is altered due to hydrolysis and radiolysis, forming materials that influence product losses, product decontamination, and separation efficiencies. In most processes, the solvent is recycled after cleaning. Solvent cleaning generally involves scrubbing with a sodium carbonate solution. Studies at the Savannah River Laboratory have shown that carbonate washing, although removing residual solvent activity, does not remove more solvent-soluble binding ligands (formed by solvent degradation), which hold fission products in the solvent. Treatment of the solvent with a solid adsorbent after carbonate washing removes binding ligands and significantly improves recycled solvent performance. Laboratory work to establish the advantage of adsorbent cleaning and the development of a full-scale adsorption process is described. The application of this process for cleaning the first cycle solvent of a Savannah River Plant production process is discussed

Substitution of chlorinated and fluorinated solvents by biodegradable detergent solution in components cleaning of nuclear fuel elements

International Nuclear Information System (INIS)

Vieira, Andre Luiz Pinto da Silva

2000-01-01

As the auxiliary oils used in machining evolved from integral into aqueous emulsion, and later on into aqueous-solution synthetic oils, the components cleaning process with organic solvents, originally adopted at the Fuel Element Factory (FEC), Industrias Nucleares do Brasil S.A. (INB) began to present problems in removing oil residues from machined components, due to the incompatibility between aqueous and organic media. In order to eliminate such incompatibility and adapt the process to the environmental laws restricting production and use of chlorinated or fluorinated solvents as a measure for preserving the atmosphere's ozone layer, in 1995 INB initiated the development of a components cleaning process using biodegradable aqueous detergent. The effort was completed in 2000 with the construction of a machine in keeping with the specific geometry of the fuel-assembly components and the operating conditions required for working with the new process. (author)

Automated cleaning of electronic components

International Nuclear Information System (INIS)

Drotning, W.; Meirans, L.; Wapman, W.; Hwang, Y.; Koenig, L.; Petterson, B.

1994-01-01

Environmental and operator safety concerns are leading to the elimination of trichloroethylene and chlorofluorocarbon solvents in cleaning processes that remove rosin flux, organic and inorganic contamination, and particulates from electronic components. Present processes depend heavily on these solvents for manual spray cleaning of small components and subassemblies. Use of alternative solvent systems can lead to longer processing times and reduced quality. Automated spray cleaning can improve the quality of the cleaning process, thus enabling the productive use of environmentally conscious materials, while minimizing personnel exposure to hazardous materials. We describe the development of a prototype robotic system for cleaning electronic components in a spray cleaning workcell. An important feature of the prototype system is the capability to generate the robot paths and motions automatically from the CAD models of the part to be cleaned, and to embed cleaning process knowledge into the automatically programmed operations

Replacement of Hydrochlorofluorocarbon (HCFC) -225 Solvent for Cleaning and Verification Sampling of NASA Propulsion Oxygen Systems Hardware, Ground Support Equipment, and Associated Test Systems

Science.gov (United States)

Mitchell, Mark A.; Lowrey, Nikki M.

2015-01-01

Since the 1990's, when the Class I Ozone Depleting Substance (ODS) chlorofluorocarbon-113 (CFC-113) was banned, NASA's rocket propulsion test facilities at Marshall Space Flight Center (MSFC) and Stennis Space Center (SSC) have relied upon hydrochlorofluorocarbon-225 (HCFC-225) to safely clean and verify the cleanliness of large scale propulsion oxygen systems. Effective January 1, 2015, the production, import, export, and new use of HCFC-225, a Class II ODS, was prohibited by the Clean Air Act. In 2012 through 2014, leveraging resources from both the NASA Rocket Propulsion Test Program and the Defense Logistics Agency - Aviation Hazardous Minimization and Green Products Branch, test labs at MSFC, SSC, and Johnson Space Center's White Sands Test Facility (WSTF) collaborated to seek out, test, and qualify a replacement for HCFC-225 that is both an effective cleaner and safe for use with oxygen systems. Candidate solvents were selected and a test plan was developed following the guidelines of ASTM G127, Standard Guide for the Selection of Cleaning Agents for Oxygen Systems. Solvents were evaluated for materials compatibility, oxygen compatibility, cleaning effectiveness, and suitability for use in cleanliness verification and field cleaning operations. Two solvents were determined to be acceptable for cleaning oxygen systems and one was chosen for implementation at NASA's rocket propulsion test facilities. The test program and results are summarized. This project also demonstrated the benefits of cross-agency collaboration in a time of limited resources.

Alternative Solvents through Green Chemistry Project

Science.gov (United States)

Hintze, Paul E.; Quinn, Jacqueline

2014-01-01

Components in the aerospace industry must perform with accuracy and precision under extreme conditions, and surface contamination can be detrimental to the desired performance, especially in cases when the components come into contact with strong oxidizers such as liquid oxygen. Therefore, precision cleaning is an important part of a components preparation prior to utilization in aerospace applications. Current cleaning technologies employ a variety of cleaning agents, many of which are halogenated solvents that are either toxic or cause environmental damage. Thus, this project seeks to identify alternative precision cleaning solvents and technologies, including use of less harmful cleaning solvents, ultrasonic and megasonic agitation, low-pressure plasma cleaning techniques, and supercritical carbon dioxide extraction. Please review all data content found in the Public Data tab located at: https:techport.nasa.govview11697public

Results of the Test Program for Replacement of AK-225G Solvent for Cleaning NASA Propulsion Oxygen Systems

Science.gov (United States)

Lowrey, Nikki M.; Mitchell, Mark A.

2016-01-01

Since the 1990's, when the Class I Ozone Depleting Substance (ODS) chlorofluorocarbon-113 (CFC-113) was banned, NASA's propulsion test facilities at Marshall Space Flight Center (MSFC) and Stennis Space Center (SSC) have relied upon the solvent AsahiKlin AK-225 (hydrochlorofluorocarbon-225ca/cb or HCFC-225ca/cb) and, more recently AK-225G (the single isomer form, HCFC-225cb) to safely clean and verify the cleanliness of large scale propulsion oxygen systems. Effective January 1, 2015, the production, import, export, and new use of Class II Ozone Depleting Substances, including AK-225G, was prohibited in the United States by the Clean Air Act. In 2012 through 2014, NASA test labs at MSFC, SSC, and Johnson Space Center's White Sands Test Facility (WSTF) collaborated to seek out, test, and qualify a solvent replacement for AK-225G that is both an effective cleaner and safe for use with oxygen systems. This paper summarizes the tests performed, results, and lessons learned.

40 CFR Table 4 to Subpart Jj of... - Pollutants Excluded From Use in Cleaning and Washoff Solvents

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Pollutants Excluded From Use in Cleaning and Washoff Solvents 4 Table 4 to Subpart JJ of Part 63 Protection of Environment ENVIRONMENTAL... Operations Pt. 63, Subpt. JJ, Table 4 Table 4 to Subpart JJ of Part 63—Pollutants Excluded From Use in...

Investigation of the Use of a Bio-Derived Solvent for Non-Solvent-Induced Phase Separation (NIPS Fabrication of Polysulfone Membranes

Directory of Open Access Journals (Sweden)

Xiaobo Dong

2018-05-01

Full Text Available Organic solvents, such as N-methyl-2-pyrrolidone (NMP and dimethylacetamide (DMAc, have been traditionally used to fabricate polymeric membranes. These solvents may have a negative impact on the environment and human health; therefore, using renewable solvents derived from biomass is of great interest to make membrane fabrication sustainable. Methyl-5-(dimethylamino-2-methyl-5-oxopentanoate (Rhodiasolv PolarClean is a bio-derived, biodegradable, nonflammable and nonvolatile solvent. Polysulfone is a commonly used polymer to fabricate membranes due to its thermal stability, strong mechanical strength and good chemical resistance. From cloud point curves, PolarClean showed potential to be a solvent for polysulfone. Membranes prepared with PolarClean were investigated in terms of their morphology, porosity, water permeability and protein rejection, and were compared to membranes prepared with traditional solvents. The pores of polysulfone/PolarClean membranes were sponge-like, and the membranes displayed higher water flux values (176.0 ± 8.8 LMH along with slightly higher solute rejection (99.0 ± 0.51%. On the other hand, PSf/DMAc membrane pores were finger-like with lower water flux (63.1 ± 12.4 LMH and slightly lower solute rejection (96 ± 2.00% when compared to PSf/PolarClean membranes.

Fluid dynamic effects on precision cleaning with supercritical fluids

Energy Technology Data Exchange (ETDEWEB)

Phelps, M.R.; Hogan, M.O.; Silva, L.J.

1994-06-01

Pacific Northwest Laboratory staff have assembled a small supercritical fluids parts cleaning test stand to characterize how system dynamics affect the efficacy of precision cleaning with supercritical carbon dioxide. A soiled stainless steel coupon, loaded into a ``Berty`` autoclave, was used to investigate how changes in system turbulence and solvent temperature influenced the removal of test dopants. A pulsed laser beam through a fiber optic was used to investigate real-time contaminant removal. Test data show that cleaning efficiency is a function of system agitation, solvent density, and temperature. These data also show that high levels of cleaning efficiency can generally be achieved with high levels of system agitation at relatively low solvent densities and temperatures. Agitation levels, temperatures, and densities needed for optimal cleaning are largely contaminant dependent. Using proper system conditions, the levels of cleanliness achieved with supercritical carbon dioxide compare favorably with conventional precision cleaning methods. Additional research is currently being conducted to generalize the relationship between cleaning performance and parameters such as contaminant solubilities, mass transfer rates, and solvent agitation. These correlations can be used to optimize cleaning performance, system design, and time and energy consumption for particular parts cleaning applications.

Dry-cleaning with high-pressure carbon dioxide

NARCIS (Netherlands)

Van Roosmalen, M.J.E.

2003-01-01

Dry-cleaning is a process for removing soils and stains from fabrics and garments which uses a non-aqueous solvent with detergent added. The currently most used dry-cleaning solvent is perchloroethylene (PER), which is toxic, environmentally harmful and suspected to be carcinogenic. Carbon dioxide

Alternative, Green Processes for the Precision Cleaning of Aerospace Hardware

Science.gov (United States)

Maloney, Phillip R.; Grandelli, Heather Eilenfield; Devor, Robert; Hintze, Paul E.; Loftin, Kathleen B.; Tomlin, Douglas J.

2014-01-01

Precision cleaning is necessary to ensure the proper functioning of aerospace hardware, particularly those systems that come in contact with liquid oxygen or hypergolic fuels. Components that have not been cleaned to the appropriate levels may experience problems ranging from impaired performance to catastrophic failure. Traditionally, this has been achieved using various halogenated solvents. However, as information on the toxicological and/or environmental impacts of each came to light, they were subsequently regulated out of use. The solvent currently used in Kennedy Space Center (KSC) precision cleaning operations is Vertrel MCA. Environmental sampling at KSC indicates that continued use of this or similar solvents may lead to high remediation costs that must be borne by the Program for years to come. In response to this problem, the Green Solvents Project seeks to develop state-of-the-art, green technologies designed to meet KSCs precision cleaning needs.Initially, 23 solvents were identified as potential replacements for the current Vertrel MCA-based process. Highly halogenated solvents were deliberately omitted since historical precedents indicate that as the long-term consequences of these solvents become known, they will eventually be regulated out of practical use, often with significant financial burdens for the user. Three solvent-less cleaning processes (plasma, supercritical carbon dioxide, and carbon dioxide snow) were also chosen since they produce essentially no waste stream. Next, experimental and analytical procedures were developed to compare the relative effectiveness of these solvents and technologies to the current KSC standard of Vertrel MCA. Individually numbered Swagelok fittings were used to represent the hardware in the cleaning process. First, the fittings were cleaned using Vertrel MCA in order to determine their true cleaned mass. Next, the fittings were dipped into stock solutions of five commonly encountered contaminants and were

Critical cleaning agents for Di-2-ethylhexyl sebacate.

Energy Technology Data Exchange (ETDEWEB)

Hartley, Mya; Archuleta, Kim M.

2013-08-01

It is required that Di-2-ethylhexyl Sebacate oil, also commonly known as Dioctyl Sebacate oil, be thoroughly removed from certain metals, in this case stainless steel parts with narrow, enclosed spaces. Dioctyl Sebacate oil is a synthetic oil with a low compressibility. As such, it is ideally used for high pressure calibrations. The current method to remove the Dioctyl Sebacate from stainless steel parts with narrow, enclosed spaces is a labor-intensive, multi-step process, including a detergent clean, a deionized (DI) water rinse, and several solvent rinses, to achieve a nonvolatile residue of 0.04 mg per 50 mL rinse effluent. This study was undertaken to determine a superior detergent/solvent cleaning method for the oil to reduce cleaning time and/or the amount of detergent/solvent used. It was determined that while some detergent clean the oil off the metal better than the current procedure, using only solvents obtained the best result. In addition, it can be inferred, based on elevated temperature test results, that raising the temperature of the oil-contaminated stainless steel parts to approximately 50ÀC will provide for improved cleaning efficacy.

Exposure to organic solvents used in dry cleaning reduces low and high level visual function.

Directory of Open Access Journals (Sweden)

Ingrid Astrid Jiménez Barbosa

Full Text Available To investigate whether exposure to occupational levels of organic solvents in the dry cleaning industry is associated with neurotoxic symptoms and visual deficits in the perception of basic visual features such as luminance contrast and colour, higher level processing of global motion and form (Experiment 1, and cognitive function as measured in a visual search task (Experiment 2.The Q16 neurotoxic questionnaire, a commonly used measure of neurotoxicity (by the World Health Organization, was administered to assess the neurotoxic status of a group of 33 dry cleaners exposed to occupational levels of organic solvents (OS and 35 age-matched non dry-cleaners who had never worked in the dry cleaning industry. In Experiment 1, to assess visual function, contrast sensitivity, colour/hue discrimination (Munsell Hue 100 test, global motion and form thresholds were assessed using computerised psychophysical tests. Sensitivity to global motion or form structure was quantified by varying the pattern coherence of global dot motion (GDM and Glass pattern (oriented dot pairs respectively (i.e., the percentage of dots/dot pairs that contribute to the perception of global structure. In Experiment 2, a letter visual-search task was used to measure reaction times (as a function of the number of elements: 4, 8, 16, 32, 64 and 100 in both parallel and serial search conditions.Dry cleaners exposed to organic solvents had significantly higher scores on the Q16 compared to non dry-cleaners indicating that dry cleaners experienced more neurotoxic symptoms on average. The contrast sensitivity function for dry cleaners was significantly lower at all spatial frequencies relative to non dry-cleaners, which is consistent with previous studies. Poorer colour discrimination performance was also noted in dry cleaners than non dry-cleaners, particularly along the blue/yellow axis. In a new finding, we report that global form and motion thresholds for dry cleaners were also

Determination of a cleaning and decontamination process using solvents; Determination d'une methode de nettoyage et de decontamination par solvant

Energy Technology Data Exchange (ETDEWEB)

Boutot, P; Schipfer, P [Commissariat a l' Energie Atomique, Chusclan (France). Centre de Production de Plutonium de Marcoule

1967-03-15

This work has been carried out on samples of the white cotton serge material of which most of the working overalls of the Nuclear Research Centre are made. The aims are: - to determine,from the decontamination and cleaning points of view, the efficiency of various solvents (white-spirit, trichloroethylene, perchlorethylene and tri-chloro-trifluoroethane) and the role of additives likely to improve the treatment; - to control the textile from the wear and shrinkage points of view; - to try to develop a basic cleaning and decontamination process as a function of the possibilities of each solvent considered. (authors) [French] Cette experimentation pratiquee sur des echantillons de tissu en serge de coton blanc, tissu dans lequel est confectionnee la majorite des tenues de travail du Centre, a pour but: - de determiner, sous l'angle decontamination et nettoyage, l'efficacite de differents solvants (white-spirit, trichlorethylene, perchlorethylene et trichlorotrifluoroethane) ainsi que le role des adjuvants susceptibles d'ameliorer le traitement; - de controler le textile du point de vue usure et retrecissement; - d'essayer de mettre au point un procede de nettoyage et de decontamination type en fonction des possibilites d'emploi de chacun des solvants consideres. (auteurs)

Exposure to tetrachloroethylene in dry cleaning shops in the Nordic countries

DEFF Research Database (Denmark)

Lynge, Elsebeth; Tinnerberg, Håkan; Rylander, Lars

2011-01-01

Tetrachloroethylene is the dominant solvent used in dry cleaning worldwide and many workers are potentially exposed. We report here on results of 1296 measurements of tetrachloroethylene undertaken in Nordic dry cleaning shops 1947-2001.......Tetrachloroethylene is the dominant solvent used in dry cleaning worldwide and many workers are potentially exposed. We report here on results of 1296 measurements of tetrachloroethylene undertaken in Nordic dry cleaning shops 1947-2001....

Brushless Cleaning of Solar Panels and Windows

Science.gov (United States)

Schneider, H. W.

1982-01-01

Machine proposed for cleaning solar panels and reflectors uses multiple vortexes of air, solvent, and water to remove dust and dirt. Uses no brushes that might abrade solar surfaces and thereby reduce efficiency. Machine can be readily automated and can be used on curved surfaces such as aparbolic reflectors as well as on flat ones. Cleaning fluids are recycled, so that large quantities of water and solvent are not needed.

Application of method of organizational congruences to substitution of organic solvents with vegetable agents for cleaning offset printing machine

Energy Technology Data Exchange (ETDEWEB)

Salerno, S [ENEA, Casaccia (Italy). Area Energia Ambiente e Salute; Tartaglia, R [Unita Sanitaria Locale 10/D, Firenze (Italy); Garzi, S; Biagioni, A [Istituto tecnico Leonardo da Vinci, Firenze (Italy)

1995-06-01

The aim of this research is the application of the method of organizational congruences before and after the substitution of organic solvents with vegetable agents for the cleaning offset printing machine in order to assess the organizational changes. A solvent free process is the goal of the SUBSPRINT project (Technology Transfer Program of the European Community). In this study it is shown how human and environmental health is improved by using vegetable agents through this change may lead to some other organizational constraints such as the time needed, the monotony and repetitiveness of the technical actions involved. The authors underline that the knowledge of the new technology impact of health help for a better understanding of the resistance to the change and help for a further amelioration of it.

Is dry cleaning all wet?

International Nuclear Information System (INIS)

Ryan, M.

1993-01-01

Chemical solvents from dry cleaning, particularly perchloroethylene (perc), have contributed to groundwater contamination, significant levels of air pollution in and around cleaners, and chemical accumulation in food. Questions are being raised about the process of cleaning clothes with chemical, and other less toxic cleaning methods are being explored. The EPA has focused attention on the 50 year old Friedburg method of cleaning, Ecoclean, which uses no dangerous chemicals and achieves comparable results. Unfortunately, the cleaning industry is resistant to change, so cutting back on amount of clothes that need dry cleaning and making sure labels aren't exaggerating when they say dry clean only, is frequently the only consumer option now

Radiological pathways analysis for spent solvents from the boiler chemical cleaning at the Pickering Nuclear Site

International Nuclear Information System (INIS)

Garisto, N.C.; Eslami, Z.; Hodgins, S.; Beaman, T.; Von Svoboda, S.; Marczak, J.

2006-01-01

Spent solvents are generated as a result of Boiler Chemical Cleanings (BCC) at CANDU reactor sites. These solutions contain small amount of radioactivity from a number of different sources including: Cut tubes - short sections of boiler tubes are infrequently removed from the boilers for a detailed characterization. These tubes are typically only plugged at the tubesheet allowing the primary side deposits to be exposed to BCC solvents. Tube leaks - primary to secondary side leaks also occur infrequently as a result of tube degradation. Radioactivity from the leaking fluid can consequently be deposited in the sludge on the secondary side of the tubes. Diffusion of tritium - during normal operation of the reactor units, tritium slowly diffuses from the heavy water in the primary heat-transfer system to the light-water coolant on the secondary side. Some of this tritium is retained in the secondary side deposits. The Pickering Nuclear Generating Station (PNGS) would like the flexibility to have several options for handling the spent solvent waste and associated rinse water from BCC. To this end, a radiological pathways analysis was undertaken to determine dose consequences associated with each option. Sample results from this study are included in this paper. The pathways analysis is used in this study to calculate dose to hypothetical receptors including individuals such as truck drivers, incinerator workers, residue (ash) handlers, residents who live near the landfill, inadvertent intruders into the landfill after closure and residents who live near the outfall. This dose is compared to a de minimis dose. A de minimis dose or dose rate represents a level of risk, which is generally accepted as being of no significance. Shipments of spent solvents and rinse water with corresponding doses below de minimis can be sent to conventional (i.e., non-radioactive) landfills for incineration and disposal as the radioactive dose associated with them is much less than natural

75 FR 34647 - Approval of the Clean Air Act, Section 112(l), Authority for Hazardous Air Pollutants: Air...

Science.gov (United States)

2010-06-18

... Solvent NESHAP for cleaning or drying parts, except any cold cleaning machine that uses a solvent which... cleaning machines in which parts such as film, coils, wire, and metal strips are cleaned at speeds... requires each cleaning machine to have [[Page 34650

Textile Dry Cleaning Using Carbon Dioxide : Process, Apparatus and Mechanical Action

NARCIS (Netherlands)

Sutanto, S.

2014-01-01

Fabrics that are sensitive to water, may wrinkle or shrink when washed in regular washing machines and are usually cleaned by professional dry cleaners. Dry cleaning is a process of removing soils from substrate, in this case textile, using a non-aqueous solvent. The most common solvent in

Efficient methods of nanoimprint stamp cleaning based on imprint self-cleaning effect

Energy Technology Data Exchange (ETDEWEB)

Meng Fantao; Chu Jinkui [Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, 116024 Dalian (China); Luo Gang; Zhou Ye; Carlberg, Patrick; Heidari, Babak [Obducat AB, SE-20125 Malmoe (Sweden); Maximov, Ivan; Montelius, Lars; Xu, H Q [Division of Solid State Physics, Lund University, Box 118, S-22100 Lund (Sweden); Nilsson, Lars, E-mail: ivan.maximov@ftf.lth.se [Department of Food Technology, Engineering and Nutrition, Lund University, Box 117, S-22100 Lund (Sweden)

2011-05-06

Nanoimprint lithography (NIL) is a nonconventional lithographic technique that promises low-cost, high-throughput patterning of structures with sub-10 nm resolution. Contamination of nanoimprint stamps is one of the key obstacles to industrialize the NIL technology. Here, we report two efficient approaches for removal of typical contamination of particles and residual resist from stamps: thermal and ultraviolet (UV) imprinting cleaning-both based on the self-cleaning effect of imprinting process. The contaminated stamps were imprinted onto polymer substrates and after demolding, they were treated with an organic solvent. The images of the stamp before and after the cleaning processes show that the two cleaning approaches can effectively remove contamination from stamps without destroying the stamp structures. The contact angles of the stamp before and after the cleaning processes indicate that the cleaning methods do not significantly degrade the anti-sticking layer. The cleaning processes reported in this work could also be used for substrate cleaning.

Dealing with the chlorinated solvent situation at the Oak Ridge Y-12 Plant

International Nuclear Information System (INIS)

Thompson, L.M.; Simandl, R.F.

1993-01-01

Recent events regarding health and environmental problems associated with the use of chlorinated solvents have prompted the Oak Ridge Y-12 Plant to investigate substitutes for these materials. Since 1987, the purchase of chlorinated solvents at the Y-12 Plant has been reduced by 92%. This has been accomplished by substituting chlorinated solvent degreasing with ultrasonic aqueous detergent cleaning and by substituting chlorinated solvents with less toxic, environmentally friendly solvents for hand-wiping applications. Extensive studies of cleaning ability, compabitility, and effects on welding, bonding, and painting have been conducted to gain approval for use of these solvents. Toxicity and waste disposal were also assessed for the solvents

Plasma cleaning for waste minimization

Energy Technology Data Exchange (ETDEWEB)

Ward, P.P.

1993-07-01

Although plasma cleaning is a recognized substitute for solvent cleaning in removing organic contaminants, some universal problems in plasma cleaning processes prevent wider use of plasma techniques. Lack of understanding of the fundamental mechanisms of the process, unreliable endpoint detection techniques, and slow process times make plasma cleaning processes less than desirable. Our approach to address these plasma cleaning problems is described. A comparison of plasma cleaning rates of oxygen and oxygen/sulfur hexafluoride gases shows that fluorine-containing plasmas can enhance etch rates by 400% over oxygen alone. A discussion of various endpoint indication techniques is discussed and compared for application suitability. Work toward a plasma cleaning database is discussed. In addition to the global problems of plasma cleaning, an experiment where the specific mixed-waste problem of removal of machine oils from radioactive scrap metal is discussed.

Monitor Clean and Efficient. Background information. Methods and references as applied in the Monitor in April 2009

International Nuclear Information System (INIS)

Gerdes, J.; De Ligt, T.

2010-01-01

This report contains background information about the Monitor Clean and Efficient that was published in April 2009. The goal and approach of the Monitor are clarified, as well as the methods and data that are used. The structure of this report resembles the structure of the Monitor. Sources and dates of availability are mentioned along with the data, as are the parties collecting and processing the information. The results that were found using this methodology have been published in the Monitor Clean and Efficient. [nl

SAGE 2.1: SOLVENT ALTERNATIVES GUIDE: USER'S GUIDE

Science.gov (United States)

The guide provides instruction for using the SAGE (Solvent Alternatives GuidE) software system, version 2.1. SAGE recommends solvent replacements in cleaning and degreasing operations. It leads the user through a question-and-answer session. The user's responses allow the system ...

Replacement Technologies for Precision Cleaning of Aerospace Hardware for Propellant Service

Science.gov (United States)

Beeson, Harold; Kirsch, Mike; Hornung, Steven; Biesinger, Paul

1997-01-01

The NASA White Sands Test Facility (WSTF) is developing cleaning and verification processes to replace currently used chlorofluorocarbon-l13- (CFC-113-) based processes. The processes being evaluated include both aqueous- and solvent-based techniques. Replacement technologies are being investigated for aerospace hardware and for gauges and instrumentation. This paper includes the findings of investigations of aqueous cleaning and verification of aerospace hardware using known contaminants, such as hydraulic fluid and commonly used oils. The results correlate nonvolatile residue with CFC 113. The studies also include enhancements to aqueous sampling for organic and particulate contamination. Although aqueous alternatives have been identified for several processes, a need still exists for nonaqueous solvent cleaning, such as the cleaning and cleanliness verification of gauges used for oxygen service. The cleaning effectiveness of tetrachloroethylene (PCE), trichloroethylene (TCE), ethanol, hydrochlorofluorocarbon 225 (HCFC 225), HCFC 141b, HFE 7100(R), and Vertrel MCA(R) was evaluated using aerospace gauges and precision instruments and then compared to the cleaning effectiveness of CFC 113. Solvents considered for use in oxygen systems were also tested for oxygen compatibility using high-pressure oxygen autogenous ignition and liquid oxygen mechanical impact testing.

An assessment of alternatives for replacing Freon 113 in bench type electrical circuit board cleaning at Fermi National Accelerator Laboratory

International Nuclear Information System (INIS)

Isakson, K.; Vessell, A.L.

1994-07-01

Fermilab is presently phasing out all solvents containing Freon-113 (CFC-113) as part of the continuing Waste Minimization Program. These solvents are used primarily in cleaning the flux off of electronic circuit boards after soldering, specifically in bench type work. Title VI of the Clean Air Act mandates a production phase-out for ozone depleting substances, like CFC-113, by the year 2000. Our study addresses this issue by evaluating and choosing alternative non-CFC solvents to replace the CFC-1 13 solvents at Fermilab. Several potential non-CFC cleaning solvents were tested. The evaluation took place in three parts: controlled experimental evaluation, chemical composition evaluation, and employee performed evaluation. First, we performed a controlled nine-step procedure with the potential solvents where each was evaluated in categories such as cleaning effectiveness, odor, residue, type of output and drying time. Next, we listed the chemical composition of each solvent. We noted which solvents contained hydrochlorofluorocarbons because they are targeted for phase-out in the future and will be recognized as interim solutions only. Finally, after preliminary testing, five solvents were chosen as the best options. These solvents were sent to be tested by Fermilab employees who use such materials. Their opinions are valuable not only because they are knowledgeable in this field, but also because they will be using the solvents chosen to replace the CFC-113 solvents. The results favored two ''best alternatives'': Safezone Solvent Flux Remover by Miller-Stephenson and E-Series CFC Free Flux-Off 2000 by Chemtech. Another possible solution also pursued is the no-clean solder option. In our study, we were not able to thoroughly investigate the many types of no-clean solders because of time and financial constraints. The testing that was done, however, showed that no-clean solder was a viable alternative in many cases

Chemical cleaning of Dresden Unit 1: Final report

International Nuclear Information System (INIS)

1986-05-01

The introduction of NS-1 solvent into the full primary system of Dresden Unit-1 nuclear power reactor on September 12, 1984, represented the culmination of several years of development, testing, planning, and construction. The requirement was to dissolve the highly radioactive deposits of primarily nickel ferrite without any corrosion which might compromise the reactor systems. During the actual cleaning with the NS-1 solvent, the chemical condition of the circulating solvent was measured. Iron, nickel, and radioactive cobalt all dissolved smoothly. The amount of copper in solution decreased in concentration, verifying expectations that metallic copper would plate on to clean metal surfaces. A special rinse formulation was employed after the primary cleaning steps and the ''lost'' copper was thus redissolved and removed from the system. After the cleaning was complete and the reactor had been refilled with pure water, radiation levels were measured. The most accurate of these measurements gave decontamination factors ranging well above 100, which indicated a significant removal of the radioactive deposits, and demonstrated the success of this project. Treatment of the radioactive liquid wastes from this operation required volume reduction and water purification. The primary method of processing the spent cleaning solvent and rinse water was evaporation. The resulting concentrate has been stored as a liquid, awaiting solidification to allow burial at a designated site. Water which was separated during evaporation, along with the dilute rinses, was processed by various chemical means, reevaporated, treated with activated carbon, and/or demineralized before its radionuclide and chemical content was low enough to allow it to be returned to Dresden Station for treatment or disposal. 60 figs., 31 tabs

Study of chemical cleaning technique for removing sludge in secondary side of PWR SG

International Nuclear Information System (INIS)

Zhang Mengqin; Zhang Shufeng; Pan Qingchun; Yu Jinghua; Hou Shufeng

1993-12-01

The effect of components, concentration, pH, temperature, cleaning time and flowrate of chemical cleaning solvent made from EDTA mainly on Fe 3 O 4 solubility and corrosion rate of A3 carbon steel, S271 low alloy steel and 800 alloy are introduced. A small chemical cleaning test loop (30L) was built to study the cleaning technique. The effect of residue of chemical cleaning solvent on anti-corrosion performance of materials has been studied under the simulation condition of PWR (pressure water reactor) SG (steam generator) secondary side. The results show that the chemical solvent (pH = 7, 10% EDTA, 1% assistance solvent and 0.25% inhibitor A) can dissolve Fe 3 O 4 18 ∼23 g/L under the conditions of 93 +- 5 degree C, 8 hours and 112 r/min (1.8 ∼ 2.0 t/h). The corrosion rate of material is low. When the residue of EDTA is less than 0.01% there is no impact on the anti-corrosion performance of materials in PWR SG secondary side at normal operation condition (260 +- 5 degree C)

40 CFR 63.462 - Batch cold cleaning machine standards.

Science.gov (United States)

2010-07-01

.... (a) Each owner or operator of an immersion batch cold solvent cleaning machine shall comply with the... cleaning machine complying with paragraph (a)(2) or (b) of this section shall comply with the work and...

Solvent substitution

International Nuclear Information System (INIS)

1990-01-01

The DOE Environmental Restoration and Waste Management Office of Technology Development and the Air Force Engineering and Services Center convened the First Annual International Workshop on Solvent Substitution on December 4--7, 1990. The primary objectives of this joint effort were to share information and ideas among attendees in order to enhance the development and implementation of required new technologies for the elimination of pollutants associated with industrial use of hazardous and toxic solvents; and to aid in accelerating collaborative efforts and technology transfer between government and industry for solvent substitution. There were workshop sessions focusing on Alternative Technologies, Alternative Solvents, Recovery/Recycling, Low VOC Materials and Treatment for Environmentally Safe Disposal. The 35 invited papers presented covered a wide range of solvent substitution activities including: hardware and weapons production and maintenance, paint stripping, coating applications, printed circuit boards, metal cleaning, metal finishing, manufacturing, compliance monitoring and process control monitoring. This publication includes the majority of these presentations. In addition, in order to further facilitate information exchange and technology transfer, the US Air Force and DOE solicited additional papers under a general ''Call for Papers.'' These papers, which underwent review and final selection by a peer review committee, are also included in this combined Proceedings/Compendium. For those involved in handling, using or managing hazardous and toxic solvents, this document should prove to be a valuable resource, providing the most up-to-date information on current technologies and practices in solvent substitution. Individual papers are abstracted separated

Ecological effectiveness of oil spill countermeasures: how clean is clean?

International Nuclear Information System (INIS)

Baker, J.M.

1999-01-01

This paper with 94 references examines background levels of hydrocarbons and the difficulty of defining clean. Processes and timescales for natural cleaning, and factors affecting natural cleaning timescales are considered. Ecological advantages and disadvantages of clean-up methods are highlighted, and five case histories of oil spills are summarised. The relationships between ecological and socio-economic considerations, and the need for a net environmental benefit analysis which takes into account the advantages and disadvantages of clean-up responses and natural clean-up are discussed. A decision tree for evaluating the requirement for shore clean-up is illustrated. (UK)

Solvent substitution

Energy Technology Data Exchange (ETDEWEB)

1990-01-01

The DOE Environmental Restoration and Waste Management Office of Technology Development and the Air Force Engineering and Services Center convened the First Annual International Workshop on Solvent Substitution on December 4--7, 1990. The primary objectives of this joint effort were to share information and ideas among attendees in order to enhance the development and implementation of required new technologies for the elimination of pollutants associated with industrial use of hazardous and toxic solvents; and to aid in accelerating collaborative efforts and technology transfer between government and industry for solvent substitution. There were workshop sessions focusing on Alternative Technologies, Alternative Solvents, Recovery/Recycling, Low VOC Materials and Treatment for Environmentally Safe Disposal. The 35 invited papers presented covered a wide range of solvent substitution activities including: hardware and weapons production and maintenance, paint stripping, coating applications, printed circuit boards, metal cleaning, metal finishing, manufacturing, compliance monitoring and process control monitoring. This publication includes the majority of these presentations. In addition, in order to further facilitate information exchange and technology transfer, the US Air Force and DOE solicited additional papers under a general Call for Papers.'' These papers, which underwent review and final selection by a peer review committee, are also included in this combined Proceedings/Compendium. For those involved in handling, using or managing hazardous and toxic solvents, this document should prove to be a valuable resource, providing the most up-to-date information on current technologies and practices in solvent substitution. Individual papers are abstracted separated.

SAGE SOLVENT ALTERNATIVES GUIDE: SYSTEM IMPROVEMENTS FOR SELECTING INDUSTRIAL SURFACE CLEANING ALTERNATIVES

Science.gov (United States)

The paper describes computer software, called SAGE, that can provide not only cleaning recommendations but also general information on various surface cleaning options. In short, it is an advisory system which can provide users with vital information on the cleaning process optio...

Carbon dioxide cleaning pilot project

International Nuclear Information System (INIS)

Knight, L.; Blackman, T.E.

1994-01-01

In 1989, radioactive-contaminated metal at the Rocky Flats Plant (RFP) was cleaned using a solvent paint stripper (Methylene chloride). One-third of the radioactive material was able to be recycled; two-thirds went to the scrap pile as low-level mixed waste. In addition, waste solvent solutions also required disposal. Not only was this an inefficient process, it was later prohibited by the Resource Conservation and Recovery Act (RCRA), 40 CFR 268. A better way of doing business was needed. In the search for a solution to this situation, it was decided to study the advantages of using a new technology - pelletized carbon dioxide cleaning. A proof of principle demonstration occurred in December 1990 to test whether such a system could clean radioactive-contaminated metal. The proof of principle demonstration was expanded in June 1992 with a pilot project. The purpose of the pilot project was three fold: (1) to clean metal so that it can satisfy free release criteria for residual radioactive contamination at the Rocky Flats Plant (RFP); (2) to compare two different carbon dioxide cleaning systems; and (3) to determine the cost-effectiveness of decontamination process in a production situation and compare the cost of shipping the metal off site for waste disposal. The pilot project was completed in August 1993. The results of the pilot project were: (1) 90% of those items which were decontaminated, successfully met the free release criteria , (2) the Alpheus Model 250 was selected to be used on plantsite and (3) the break even cost of decontaminating the metal vs shipping the contaminated material offsite for disposal was a cleaning rate of 90 pounds per hour, which was easily achieved

Method of and apparatus for cleaning garments and soft goods contaminated with nuclear, chemical and/or biological contaminants

International Nuclear Information System (INIS)

Fowler, D.E.

1989-01-01

A method is described for decontaminating garments, soft good or mixtures thereof contaminated with radioactive particulates, toxin, chemical, and biological contaminants comprising the steps of: (a) depositing contaminated garments, soft goods or mixtures thereof in a cleaning drum; (b) charging the drum with a cleaning solvent in which the chemical contaminants are soluble; (c) agitating the drum during a wash cycle to separate radioactive, toxin, biological particulate matter of mixtures thereof from the garments; (d) draining the drum of the dry cleaning solvent which contains suspended particulate contaminants and dissolved chemical contaminants; (e) contacting the drained solvent with both a neutralizing agent and an oxidizing agent, the neutralizing agent being selected from the group consisting of sodium hydroxide, potassium hydroxide and mixtures thereof and having a concentration greater than one (1.0) normal; (f) rinsing the garments, soft goods or mixtures thereof by circulating clean solvent from a solvent tank through the drum thereby effecting additional removal and flushing of particulate and chemical contaminants; (g) filtering the circulated solvent to remove the particulate material suspended in the solvent prior to addition to the drum; and (h) preferentially adsorbing the chemical contaminants dissolved in the circulated solvent prior to addition to the drum

Benefits of integrating chemical and mechanical cleaning processes for steam generator sludge removal

International Nuclear Information System (INIS)

Varrin, R.D.; Ferriter, A.M.; Oliver, T.W.; Le Surf, J.E.

1992-01-01

This paper discusses the benefits of performing in-bundle tubesheet lancing in conjunction with chemical cleaning of PWR and PHWR steam generators in which a hard sludge pile is known to exist. The primary benefits of in-bundle lancing are to: (1) increase the exposed area of the sludge pile by cutting furrows in the surface thereby enhancing dissolution of sludge, (2) reduce the volume of solvents required since material removed by lancing does not have to be dissolved chemically, (3) improve rinsing and removal of residual solvent between iron and copper dissolution steps, and (4) allow for verification of process effectiveness by providing high quality in-bundle visual inspection. The reduction in solvent volumes can lead to a significant reduction in solvent costs and waste processing. A case study which includes an economic evaluation for a combined chemical and mechanical cleaning shows a potential cost saving of up to US$ 300,000 over use of chemical cleaning alone. 14 refs., 2 tabs., 2 figs

Chemical-Cleaning Demonstration Test No. 2 in a mock-up steam generator

International Nuclear Information System (INIS)

Jevec, J.M.; Leedy, W.S.

1983-04-01

This report describes the results of the mockup demonstration test of the first modified baseline process under Contract S-127, Chemical Cleaning of Nuclear Steam Generators. The objective of this program is to determine the feasibility of cleaning the secondary side of nuclear steam generators with state-of-the-art chemical cleaning technology. The first step was to benchmark a baseline process. This process was then modified to attempt to eliminate the causes of unacceptable cleaning performance. The modified baseline process consists of an EDTA/H 2 O 2 -based copper solvent and a near-neutral, EDTA/N 2 H 4 -based magnetite and crevice solvent. This report also presents the results of three inhibitor evaluation mockup runs used in the evaluation of the modified baseline process

40 CFR 446.10 - Applicability; description of the oil-base solvent wash paint subcategory.

Science.gov (United States)

2010-07-01

...-base solvent wash paint subcategory. 446.10 Section 446.10 Protection of Environment ENVIRONMENTAL...-Base Solvent Wash Paint Subcategory § 446.10 Applicability; description of the oil-base solvent wash... production of oil-base paint where the tank cleaning is performed using solvents. When a plant is subject to...

Solvent Handbook Database System user's manual

International Nuclear Information System (INIS)

1993-03-01

Industrial solvents and cleaners are used in maintenance facilities to remove wax, grease, oil, carbon, machining fluids, solder fluxes, mold release, and various other contaminants from parts, and to prepare the surface of various metals. However, because of growing environmental and worker-safety concerns, government regulations have already excluded the use of some chemicals and have restricted the use of halogenated hydrocarbons because they affect the ozone layer and may cause cancer. The Solvent Handbook Database System lets you view information on solvents and cleaners, including test results on cleaning performance, air emissions, recycling and recovery, corrosion, and non-metals compatibility. Company and product safety information is also available

Evaluation of boiler chemical cleaning techniques

International Nuclear Information System (INIS)

1993-04-01

The EPRI/SGOG process, which has been selected by Ontario Hydro for use at the Bruce A station, is described. This process consists of alternating iron removal and copper removal steps, the two metals which comprise the bulk of the deposit in the Bruce A SGs. The iron removal solvent consists of ethylenediameinetetraacetic acid (EDTA), hydrazine, ammonium hydroxide and a proprietary corrosion inhibitor CCI-801. The copper removal solvent consists of EDTA, ethylene diamine and hydrogen peroxide. Ontario Hydro proposes to clean a bank of four SGs in parallel employing a total of six copper removal steps and four iron removal steps. Cleaning all eight SGs in a single Bruce A unit will generate 2,200 m 3 of liquid waste which will be treated by a wet air oxidation process. The iron and copper sludges will be buried in a landfill site while the liquid waste will be further treated by the Bruce sewage treatment plant. Some ammonia vapour will be generated through the wet air oxidation process and will be vented through a stack on top of the high bay of the spent solvent treatment plant. With the exception of the proprietary corrosion inhibitor, all chemicals that will be employed in the cleaning and waste treatment operations are standard industrial chemicals which are well characterized. No extraordinary hazards are anticipated with their use as long as adequate safety precautions are taken

A centrifuge CO2 pellet cleaning system

International Nuclear Information System (INIS)

Foster, C.A.; Fisher, P.W.; Nelson, W.D.; Schechter, D.E.

1993-01-01

Centrifuge-based cryogenic pellet accelerator technology, originally developed at Oak Ridge National Laboratory (ORNL) for the purpose of refueling fusion reactors with high-speed pellets of frozen deuterium/tritium,is now being developed as a method of cleaning without the use of conventional solvents. In these applications large quantities of pellets made of frozen CO 2 or argon are accelerated in a high-speed rotor. The accelerated pellet stream is used to clean or etch surfaces. The advantage of this system is that the spent pellets and debris resulting from the cleaning process can be filtered leaving only the debris for disposal. This paper discusses the centrifuge CO 2 pellet cleaning system, the physics model of the pellet impacting the surface, the centrifuge apparatus, and some initial cleaning and etching tests

Oak Ridge K-25 Site chlorinated solvent pollution prevention opportunity assessment

Energy Technology Data Exchange (ETDEWEB)

1994-08-01

A pollution prevention opportunity assessment (PPOA) was conducted at the Oak Ridge K-25 Site to identify opportunities to reduce and better manage the use of chlorinated solvents. At the K-25 Site, 67 control areas were examined for their potential use of chlorinated solvents. Of these areas, 27 were found to be using (1) chlorinated solvents for cleaning, degreasing, and lubricating; (2) laboratory standards and solvents; and (3) test medium. Current management practices encourage the identification and use of nonhazardous chemicals, including the use of chlorinated solvents. The main pollution prevention principles are source reduction and recycling, and a number of pollution prevention options based on these principles were identified and evaluated as part of this chlorinated solvent PPOA. Source reduction options evaluated for the K-25 Site include the substitution of chlorinated solvents with nonchlorinated solvents. Recycling was identified for those areas that would benefit most from the reuse of the chlorinated solvents in use. The pollution prevention options that offer the greatest opportunity for success at the K-25 Site are the implementation of substitutes at the 10 control areas using chlorinated solvents for cleaning, degreasing, and lubrication. A change in the process may be all that is needed to eliminate the use of a chlorinated solvent. Once a decision is made to implement a substitution, the information should be communicated to all shops and laboratories. Another option to consider is the installation of recycling units to recycle the large amounts of methylene chloride used in the analytical sampling procedure.

Oak Ridge K-25 Site chlorinated solvent pollution prevention opportunity assessment

International Nuclear Information System (INIS)

1994-08-01

A pollution prevention opportunity assessment (PPOA) was conducted at the Oak Ridge K-25 Site to identify opportunities to reduce and better manage the use of chlorinated solvents. At the K-25 Site, 67 control areas were examined for their potential use of chlorinated solvents. Of these areas, 27 were found to be using (1) chlorinated solvents for cleaning, degreasing, and lubricating; (2) laboratory standards and solvents; and (3) test medium. Current management practices encourage the identification and use of nonhazardous chemicals, including the use of chlorinated solvents. The main pollution prevention principles are source reduction and recycling, and a number of pollution prevention options based on these principles were identified and evaluated as part of this chlorinated solvent PPOA. Source reduction options evaluated for the K-25 Site include the substitution of chlorinated solvents with nonchlorinated solvents. Recycling was identified for those areas that would benefit most from the reuse of the chlorinated solvents in use. The pollution prevention options that offer the greatest opportunity for success at the K-25 Site are the implementation of substitutes at the 10 control areas using chlorinated solvents for cleaning, degreasing, and lubrication. A change in the process may be all that is needed to eliminate the use of a chlorinated solvent. Once a decision is made to implement a substitution, the information should be communicated to all shops and laboratories. Another option to consider is the installation of recycling units to recycle the large amounts of methylene chloride used in the analytical sampling procedure

Overview of shoreline cleaning agents

International Nuclear Information System (INIS)

Clayton, J.

1992-01-01

Chemical cleaning agents may be used to promote release of stranded oil from shorelines for reasons including biological sensitivity of indigenous fauna and flora to the oil, amenity considerations of the shoreline, or concern about refloating of the oil and subsequent stranding on adjacent shorelines. While use of chemical cleaning agents may be appropriate under proper toxic responses in circumstances, certain limitations should be recognized. The potential for toxic responses in indigenous fauna and flora to the cleaning agents must be considered. Enhanced penetration of oil into permeable shorelines following treatment with chemical cleaning agents also is not desirable. However, if conditions related to toxicity and substrate permeability are determined to be acceptable, the use of chemical cleaning agents for treatment of stranded oil can be considered. Chemical agents for cleaning oiled shorelines can be grouped into three categories: (1) non-surfactant-based solvents, (2) chemical dispersants, and (3) formulations especially designed to release stranded oil from shoreline substrates (i.e., shoreline-cleaning-agents). Depending on the specific circumstances present on an oiled shoreline, it is generally desirable that chemical agents used for cleaning will release oil from shoreline substrate(s) to surface waters. Recovery of the oil can then be accomplished by mechanical procedures such as booming and skimming operations

Green Michael addition of thiols to electron deficient alkenes using KF/alumina and recyclable solvent or solvent-free conditions

Energy Technology Data Exchange (ETDEWEB)

Lenardao, Eder J.; Trecha, Danusia O.; Ferreira, Patricia da C.; Jacob, Raquel G.; Perin, Gelson [Universidade Federal de Pelotas (UFPEL), Pelotas, RS (Brazil). Inst. de Quimica e Geociencias. Lab. de Sintese Organica Limpa (LASOL)]. E-mail: lenardao@ufpel.edu.br

2009-07-01

A general, clean and easy method for the conjugated addition of thiols to citral promoted by KF/Al{sub 2}O{sub 3} under solvent-free or using glycerin as recyclable solvent at room temperature is described. It was found that the solvent-free protocol is applicable to the direct reaction of thiophenol with the essential oil of lemon grass (Cymbopogon citratus) to afford directly 3,7-dimethyl-3-(phenylthio)oct-6-enal, a potential bactericide agent. The method was extended to other electron-poor alkenes with excellent results. For the solvent-free protocol, the use of microwave irradiation facilitated the procedure and accelerates the reaction. The catalytic system and glycerin can be reused up to three times without previous treatment with comparable activity. (author)

Trajectories towards clean technology. Example of volatile organic compound emission reductions

Energy Technology Data Exchange (ETDEWEB)

Belis-Bergouignan, Marie-Claude; Oltra, Vanessa; Saint Jean, Maider [IFREDE-E3i, University Montesquieu-Bordeaux IV, Avenue Leon Duguit, Pessac 33608 (France)

2004-02-20

This article is based on the observation that, up until now, corporate investment has been limited in clean technologies despite the will of governmental authorities to stimulate them in order to cope with the demands of sustainable development. The paper deals with the issue of the development of clean technologies and the role of regulations as clean technology promoters. It tries to apprehend the characteristics and specificity of clean technology from both an empirical and a theoretical point of view, so as to understand which are the most favourable (or inversely, the most detrimental) conditions for their development. We use case studies concerning the reduction of volatile organic compound (VOC) emissions in the chemical and metallurgical industries. These two examples highlight the problems created by the shift from a 'with-solvent paradigm' to a 'solvent-free paradigm' and the way clean technology trajectories may spread within such paradigms. We show that the problem of clean technology development primarily resides in some factors that impede technological adoption, although a strong and mixed incentives framework prevails. Such impediments are sector-specific, leading to different clean technology trajectories among sectors and indicating areas of sectoral intervention that could become the cornerstones of complementary technology policy.

Pickering Unit 1 chemical cleaning

International Nuclear Information System (INIS)

Smee, J.L.; Fiola, R.J.; Brennenstuhl, K.R.; Zerkee, D.D.; Daniel, C.M.

1995-01-01

The secondary sides of all 12 boilers at Pickering Unit 1 were chemically cleaned in 1994 by the team of Ontario Hydro, B and W International (Cambridge, Ontario) and B and W Nuclear Technologies (Lynchburg, Virginia). A multi-step EPRI/SGOG process was employed in a similar manner to previous clearings at Units 5 and 6 in 1992 and 1993, respectively. A major innovation with the Unit 1 cleaning was the incorporation of a crevice cleaning step, the first time this had been done on Ontario Hydro plants. In addition, six boilers were cleaned in parallel compared to three at a time in previous Pickering cleanings. This significantly reduced cleaning time. A total of 6,770 kg of sludge was removed through direct chemical dissolution. It consisted of 66% iron/nickel oxides and 28% copper metal. A total of 1,600,000 L (420,000 US gallons) of liquid waste was produced. It was processed through the spent solvent treatment facility located at the Bruce Nuclear Power Development site. Visual inspection performed after the cleaning indicated that the crevices between the boiler tubes and the tube support structure were completely clear of deposit and the general condition of the tubing and lattice bars appeared to be in 'as new' condition. (author)

Prioritizing substitution of organic solvents in industrial cleaning processes

DEFF Research Database (Denmark)

Rasmussen, Pia Brunn; Jacobsen, Thomas

1997-01-01

A method for prioritizing the substitution of volatile organic compounds (VOC) used in industrial cleaning processes is developed. The result is a matrix, which, if all information can be obtained, gives a comprehensive description of the effects, exposure and emission of VOC, as well as the pros...

Measurement and prediction of aromatic solute distribution coefficients for aqueous-organic solvent systems. Final report

Energy Technology Data Exchange (ETDEWEB)

Campbell, J.R.; Luthy, R.G.

1984-06-01

Experimental and modeling activities were performed to assess techniques for measurement and prediction of distribution coefficients for aromatic solutes between water and immiscible organic solvents. Experiments were performed to measure distribution coefficients in both clean water and wastewater systems, and to assess treatment of a wastewater by solvent extraction. The theoretical portions of this investigation were directed towards development of techniques for prediction of solute-solvent/water distribution coefficients. Experiments were performed to assess treatment of a phenolic-laden coal conversion wastewater by solvent extraction. The results showed that solvent extraction for recovery of phenolic material offered several wastewater processing advantages. Distribution coefficients were measured in clean water and wastewater systems for aromatic solutes of varying functionality with different solvent types. It was found that distribution coefficients for these compounds in clean water systems were not statistically different from distribution coefficients determined in a complex coal conversion process wastewater. These and other aromatic solute distribution coefficient data were employed for evaluation of modeling techniques for prediction of solute-solvent/water distribution coefficients. Eight solvents were selected in order to represent various chemical classes: toluene and benzene (aromatics), hexane and heptane (alkanes), n-octanol (alcohols), n-butyl acetate (esters), diisopropyl ether (ethers), and methylisobutyl ketone (ketones). The aromatic solutes included: nonpolar compounds such as benzene, toluene and naphthalene, phenolic compounds such as phenol, cresol and catechol, nitrogenous aromatics such as aniline, pyridine and aminonaphthalene, and other aromatic solutes such as naphthol, quinolinol and halogenated compounds. 100 references, 20 figures, 34 tables.

Cleaning and Restoration of an Oil Painting with a Polymer Gel in Iran

Directory of Open Access Journals (Sweden)

Siyamak Alizadeh

2018-03-01

Full Text Available One of the major stages in the conservation and restoration of a painting is to clean its colored surface of unwanted stains, and old and darkened varnishes. Various solvents have been used to date for this purpose; however, new cleaning materials have also come onto the market in the past decade that are still unknown and may never have been employed in Iran. The present study aims to introduce a polymer gel and use an in vitro sample of the substance for cleaning and to then present the results of the tests carried out. Applying a polymer gel in the cleaning of paintings yielded better results and greater advantages over the solvents previously used to clean artworks. The advantages include, performing on the surface without penetrating the lower layers, the absence of residues after application, flexibility, solubility and the gentle removal of old stains and varnishes, maintaining clarity and cleaning the surface by simple removal of the thin dried layer, which requires no mechanical pressure. Microscopic examinations and pH testing showed that this new alternative technique can be of use in cleaning the color layers of oil paintings.

Chemical cleaning the service water system at a nuclear power plant

International Nuclear Information System (INIS)

Brice, T.O.; Glover, W.A.

1994-01-01

Chemical cleaning a large cooling water system in a nuclear power plant presented many unique problems. The selection, qualification, and performance of the cleaning process were done using a phased approach. The piping was inspected to determine the extent of the problem. Deposit samples were removed from the service water system pipe and tested in the laboratory to determine the most effective cleaning solvent for deposit removal. An engineering study was performed to define the design parameters required to implement the system-wide chemical cleaning

PWR steam generator chemical cleaning. Phase I: Final report, Volume I

International Nuclear Information System (INIS)

1978-07-01

Two chemical cleaning solvent systems and two application methods were developed to remove the sludge in nuclear steam generators and to remove the corrosion products in the annuli between the steam generator tubes and the support plates. Laboratory testing plus subsequent pilot testing has demonstrated that, in a reasonable length of time, both solvents are capable of dissolving significant amounts of sludge, and of dissolving tightly packed magnetite in tube/support plate crevices. Further, tests have demonstrated that surface losses of the materials of construction in steam generators can be controlled to acceptable limits for the duration of the required cleaning period. Areas requiring further study and test have been identified, and a preliminary procedure for chemical cleaning nuclear steam generators has been chosen subject to quantification based on additional tests prior to actual in-plant demonstration

Mechanical cleaning of graphene

NARCIS (Netherlands)

Goossens, A.M.; Calado, V.E.; Barreiro, A.; Watanabe, K.; Taniguchi, T.; Vandersypen, L.M.K.

2012-01-01

Contamination of graphene due to residues from nanofabrication often introduces background doping and reduces electron mobility. For samples of high electronic quality, post-lithography cleaning treatments are therefore needed. We report that mechanical cleaning based on contact mode atomic force

The Jungfraujoch high-alpine research station (3454 m) as a background clean continental site for the measurement of aerosol parameters

Energy Technology Data Exchange (ETDEWEB)

Nyeki, S.; Baltensperger, U.; Jost, D.T.; Weingartner, E. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Colbeck, I. [Essex Univ., Colchester (United Kingdom)

1997-09-01

Aerosol physical parameter measurements are reported here for the first full annual set of data from the Jungfraujoch site. Comparison to NOAA background and regional stations indicate that the site may be designated as `clean continental` during the free tropospheric influenced period 03:00 -09:00. (author) figs., tab., refs.

The Jungfraujoch high-alpine research station (3454 m) as a background clean continental site for the measurement of aerosol parameters

International Nuclear Information System (INIS)

Nyeki, S.; Baltensperger, U.; Jost, D.T.; Weingartner, E.; Colbeck, I.

1997-01-01

Aerosol physical parameter measurements are reported here for the first full annual set of data from the Jungfraujoch site. Comparison to NOAA background and regional stations indicate that the site may be designated as 'clean continental' during the free tropospheric influenced period 03:00 -09:00. (author) figs., tab., refs

A new approach involving a multi transducer ultrasonic system for cleaning turbine engines' oil filters under practical conditions.

Science.gov (United States)

Nguyen, Dinh Duc; Ngo, Huu Hao; Yoon, Yong Soo; Chang, Soon Woong; Bui, Hong Ha

2016-09-01

The purpose of this paper is to provide a green technology that can clean turbine engine oil filters effectively in ships using ultrasound, with ultrasonic devices having a frequency of 25kHz and different powers of 300W and 600W, respectively. The effects of temperature, ultrasonic cleaning times, pressure losses through the oil filter, solvent washing, and ultrasonic power devices were investigated. In addition, the cleaning efficiency of three modes (hand washing, preliminary washing and ultrasonic washing) were compared to assess their relative effectiveness. Experimental results revealed that the necessary ultrasonic time varied significantly depending on which solvent was used for washing. For instance, the optimum ultrasonic cleaning time was 50-60min when the oil filter was cleaned in a solvent of kerosene oil (KO) and over 80min when in a solvent of diesel oil (DO) using the same ultrasonic generator device (25kHz, 600W) and experimental conditions. Furthermore, microscopic examination did not reveal any damage or breakdown on or within the structure of the filter after ultrasonic cleaning, even in the filter's surfaces at a constantly low frequency of 25kHz and power specific capacity (100W/gal). Overall, it may be concluded that ultrasound-assisted oil filter washing is effective, requiring a significantly shorter time than manual washing. This ultrasonic method also shows promise as a green technology for washing oil filters in turbine engines in general and Vietnamese navy ships in particular, because of its high cleaning efficiency, operational simplicity and savings. Copyright © 2016 Elsevier B.V. All rights reserved.

Next Generation Solvent Performance in the Modular Caustic Side Solvent Extraction Process - 15495

Energy Technology Data Exchange (ETDEWEB)

Smith, Tara E. [Savannah River Remediation, LLC., Aiken, SC (United States); Scherman, Carl [Savannah River Remediation, LLC., Aiken, SC (United States); Martin, David [Savannah River Remediation, LLC., Aiken, SC (United States); Suggs, Patricia [Savannah River Site (SRS), Aiken, SC (United States)

2015-01-14

Changes to the Modular Caustic Side Solvent Extraction Unit (MCU) flow-sheet were implemented in the facility. Implementation included changing the scrub and strip chemicals and concentrations, modifying the O/A ratios for the strip, scrub, and extraction contactor banks, and blending the current BoBCalixC6 extractant-based solvent in MCU with clean MaxCalix extractant-based solvent. During the successful demonstration period, the MCU process was subject to rigorous oversight to ensure hydraulic stability and chemical/radionuclide analysis of the key process tanks (caustic wash tank, solvent hold tank, strip effluent hold tank, and decontaminated salt solution hold tank) to evaluate solvent carryover to downstream facilities and the effectiveness of cesium removal from the liquid salt waste. Results indicated the extraction of cesium was significantly more effective with an average Decontamination Factor (DF) of 1,129 (range was 107 to 1,824) and that stripping was effective. The contactor hydraulic performance was stable and satisfactory, as indicated by contactor vibration, contactor rotational speed, and flow stability; all of which remained at or near target values. Furthermore, the Solvent Hold Tank (SHT) level and specific gravity was as expected, indicating that solvent integrity and organic hydraulic stability were maintained. The coalescer performances were in the range of processing results under the BOBCalixC6 flow sheet, indicating negligible adverse impact of NGS deployment. After the Demonstration period, MCU began processing via routine operations. Results to date reiterate the enhanced cesium extraction and stripping capability of the Next Generation Solvent (NGS) flow sheet. This paper presents process performance results of the NGS Demonstration and continued operations of MCU utilizing the blended BobCalixC6-MaxCalix solvent under the NGS flowsheet.

Clean Transfer of Wafer-Scale Graphene via Liquid Phase Removal of Polycyclic Aromatic Hydrocarbons.

Science.gov (United States)

Kim, Hyun Ho; Kang, Boseok; Suk, Ji Won; Li, Nannan; Kim, Kwang S; Ruoff, Rodney S; Lee, Wi Hyoung; Cho, Kilwon

2015-05-26

Pentacene (C22H14), a polycyclic aromatic hydrocarbon, was used as both supporting and sacrificing layers for the clean and doping-free graphene transfer. After successful transfer of graphene to a target substrate, the pentacene layer was physically removed from the graphene surface by using intercalating organic solvent. This solvent-mediated removal of pentacene from graphene surface was investigated by both theoretical calculation and experimental studies with various solvents. The uses of pentacene and appropriate intercalation solvent enabled graphene transfer without forming a residue from the supporting layer. Such residues tend to cause charged impurity scattering and unintentional graphene doping effects. As a result, this clean graphene exhibited extremely homogeneous surface potential profiles over a large area. A field-effect transistor fabricated using this graphene displayed a high hole (electron) mobility of 8050 cm(2)/V·s (9940 cm(2)/V·s) with a nearly zero Dirac point voltage.

CO2 dry cleaning: Acoustic cavitation and other mechanisms to induce mechanical action

NARCIS (Netherlands)

Sutanto, S.; Dutschk, Victoria; Mankiewicz, J.; van Roosmaalen, M.; Warmoeskerken, Marinus

2014-01-01

High pressure carbon dioxide (CO2) is a potential solvent for textile dry cleaning. However, the particulate soil (e.g. clay, sand) removal in CO2 is generally insufficient. Since cavitation has been proven to be beneficial in other CO2 cleaning applications, this study aims to investigate the

Vapor solvent decontamination of PCB [polychlorinated biphenyls] transformer components

International Nuclear Information System (INIS)

Green, G.R.; Green, G.R.

1992-01-01

A process is provided to recover reclaimable material from discarded transformers containing PCB (polychlorinated biphenyl) insulating oils and to minimize the volume of materials which are subject to environmental regulation upon disposal. According to the invention, the transformer is drained and given an initial cleaning. The internal parts are removed and cleaned a second time as is the empty transformer casing. Recoverable materials such as aluminum and copper are cleaned to less than 10 μg of PCB per 100 cm 2 , allowing these materials to be recycled rather than buried. Almost all of the remaining nonmetallic materials are combustible solids or liquids which can be destroyed by incineration. The cleaning is accomplished using trichloroethylene solvent, chosen for its low boiling point which makes it easy to recycle using an isothermal separator. The removed transformer parts are cleaned in a secondary cleaning station consisting of 3 separate sections including tumbling baskets. 2 figs

Final status report in preparation for the chemical cleaning of Dresden-1, DNS-D1-034

International Nuclear Information System (INIS)

1981-09-01

This report discusses the status of all of the activities conducted in preparation for the chemical cleaning of the Dresden-1 Nuclear Power Plant of Commonwealth Edison of Illinois. The metallurgical testing of a solvent and its ability to remove radioactivity are reviewed. Included are all engineering details relating to the modifications to the primary system to be able to perform the chemical cleaning and to rinse the cleaning solvent out of the equipment. A facility to store and process spent cleaning solutions is described in detail. Construction activities and preoperational activities are recounted. Licensing activities, quality assurance, safety, and radiation protection are discussed. The report includes recommendations for future actions for restarting the project when approval is received. All of the efforts discussed in this Final Status Report led to the conclusion that the chemical cleaning, as planned, was feasible. All of the necessary modifications and new equipment are in place and are operational

Evaluation of Various Cleaning Methods to Remove Bacillus Spores from Spacecraft Hardware Materials

Science.gov (United States)

Venkateswaran, Kasthuri; Chung, Shirley; Allton, Judith; Kern, Roger

2004-09-01

A detailed study was made of the biological cleaning effectiveness, defined in terms of the ability to remove bacterial spores, of a number of methods used to clean hardware surfaces. Aluminum (Al 6061) and titanium (Ti 6Al-4V) were chosen for the study as they were deemed the two materials most likely to be used in spacecraft extraterrestrial sampler construction. Metal coupons (1 cm × 2.5 cm) were precleaned and inoculated with 5.8 × 103 cultivable Bacillus subtilis spores, which are commonly found on spacecraft surfaces and in the assembly environments. The inoculated coupons were subsequently cleaned using: (1) 70% isopropyl alcohol wipe; (2) water wipe; (3) multiple-solvent flight-hardware cleaning procedures used at the Jet Propulsion Laboratory (JPL); (4) Johnson Space Center-developed ultrapure water rinse; and (5) a commercial, semi-aqueous, multiple-solvent (SAMS) cleaning process. The biological cleaning effectiveness was measured by agar plate assay, sterility test (growing in liquid media), and epifluorescent microscopy. None of the cleaning protocols tested completely removed viable spores from the surface of the aluminum. In contrast, titanium was capable of being cleaned to sterility by two methods, the JPL standard and the commercial SAMS cleaning process. Further investigation showed that the passivation step employed in the JPL standard method is an effective surface sterilant on both metals but not compatible with aluminum. It is recommended that titanium (Ti 6Al-4V) be considered superior to aluminum (Al 6061) for use in spacecraft sampling hardware, both for its potential to be cleaned to sterilization and for its ability to withstand the most effective cleaning protocols.

Changes in background aerosol composition in Finland during polluted and clean periods studied by TEM/EDX individual particle analysis

OpenAIRE

Niemi , J. V.; Saarikoski , S.; Tervahattu , H.; Mäkelä , T.; Hillamo , R.; Vehkamäki , H.; Sogacheva , L.; Kulmala , M.

2006-01-01

Aerosol samples were collected at a rural background site in southern Finland in May 2004 during pollution episode (PM1~16 µg m−3, backward air mass trajectories from south-east), intermediate period (PM1~5 µg m−3, backtrajectories from north-east) and clean period (PM1~2 µg m−3, backtrajectories from north-west/north). The elemental composition, morphology and mixing state of individual aerosol particles in three size fractions were st...

Hazardous Solvent Substitution Data System reference manual

International Nuclear Information System (INIS)

Branham-Haar, K.A.; Twitchell, K.E.

1993-07-01

Concern for the environment, in addition to Federal regulation, mandate the replacement of hazardous solvents with safer cleaning agents. Manufacturers are working to produce these replacement solvents. As these products are developed, potential users need to be informed of their availability. To promote the use of these new products instead of traditional solvents, the Idaho National Engineering Laboratory (INEL) has developed the Hazardous Solvent Substitution Data System (HSSDS). The HSSDS provides a comprehensive system of information on alternatives to hazardous solvents and related subjects, and it makes that information available to solvent users, industrial hygienists, and process engineers. The HSSDS uses TOPIC reg-sign, a text retrieval system produced by Verity, Inc., to allow a user to search for information on a particular subject. TOPIC reg-sign produces a listing of the retrieved documents and allows the use to examine the documents individually and to use the information contained in them. This reference manual does not replace the comprehensive TOPIC reg-sign user documentation (available from Verity, Inc.), or the HSSDS Tutorial (available from the INEL). The purpose of this reference manual is to provide enough instruction on TOPIC reg-sign so the user may begin accessing the data contained in the HSSDS

Terpenes as Green Solvents for Extraction of Oil from Microalgae

Directory of Open Access Journals (Sweden)

Celine Dejoye Tanzi

2012-07-01

Full Text Available Herein is described a green and original alternative procedure for the extraction of oil from microalgae. Extractions were carried out using terpenes obtained from renewable feedstocks as alternative solvents instead of hazardous petroleum solvents such as n-hexane. The described method is achieved in two steps using Soxhlet extraction followed by the elimination of the solvent from the medium using Clevenger distillation in the second step. Oils extracted from microalgae were compared in terms of qualitative and quantitative determination. No significant difference was obtained between each extract, allowing us to conclude that the proposed method is green, clean and efficient.

Validation of Alternatives to High Volatile Organic Compound Solvents Used in Aeronautical Antifriction Bearing Cleaning

Science.gov (United States)

2006-10-17

982-4832 (fax) tom.torres@navy.mil Quality Assurance Officer Gene Griffin NFESC 1100 23rd Avenue Port Hueneme, CA 93043-4370 (805) 982-2267...solvent replenishment system. The waste solvent shall be captured in a sealed container that is easily acces· sible for periodic disposal. (2) HFE ...Co-Solvent Vapor Degreaser. This method features the use of a hydrocarbon (HC) solvating agent and a Hydrofluoroether ( HFE ) liquid rinse and vapor

Cleaning of small components of complex geometry by means of the sodium-alcohol reaction

International Nuclear Information System (INIS)

De Luca, B.; Grasso, C.; Spadoni, M.

1978-01-01

The results of some experiments on the vacuum reaction between butylcellosolve and sodium, contained in small diameter capillaries, are reported. The effects on the cleaning rate of the temperature, amount of solvent, diameter and position of the capillaries are analyzed. The facility, used for the cleaning of small components of complex geometry, is described. (author)

Steam generator chemical cleaning demonstration test No. 1 in a pot boiler

International Nuclear Information System (INIS)

Key, G.L.; Helyer, M.H.

1981-04-01

The effectiveness of the Electric Power Research Institute (EPRI Mark I) chemical cleaning solvent process was tested utilizing a 12 tube pot boiler that had previously been fouled and dented under 30 days of high chloride fault chemistry operation. Specifically, the intent of this chemical cleaning test was to: (1) dissolve sludge from the tubesheet, (2) remove non-protective magnetite from dented tube/support crevice regions, and (3) quantify the extent of corrosion of steam generator material during the test. Two laboratory cleaning demonstrations of 191 and 142 hours were performed

Cancer in persons working in dry cleaning in the Nordic countries

DEFF Research Database (Denmark)

Lynge, Elsebeth; Andersen, Aage; Rylander, Lars

2006-01-01

-cleaning workers identified from the 1970 censuses in Denmark, Norway, Sweden, and Finland. Dry-cleaning work in the Nordic countries during the period when tetrachloroethylene was the dominant solvent was not associated with an increased risk of esophageal cancer [rate ratio (RR) = 0.76; 95% confidence interval...... not found in women directly involved in dry cleaning. We found an excess risk of bladder cancer (RR = 1.44; 95% CI, 1.07-1.93) not associated with length of employment. The finding of no excess risk of esophageal cancer in Nordic dry cleaners differs from U.S. findings. Chance, differences in level...

Substitution of Organic Solvents - a Way to improve Working Environment and reduce Emissions to the Atmosphere

DEFF Research Database (Denmark)

Jacobsen, Thomas

1996-01-01

solvents as cleaning agents has been reached. However, some barriers to this substitution process, are found outside the printing companies. In designing of machines and auxiliary equipment, the manufacturers must take into account, that cleaning with non-volatile agents should be possible. Even a rather...... the process in order to omit the solvents or to use water-based products. In cases, where a change to water-based is not evident, improvements can be reached by using non-volatile, low-toxic products, typically esters of fatty acids from vegetable oils. In offset printing a drastic reduction of use of organic...

78 FR 46447 - Conditional Exclusions From Solid Waste and Hazardous Waste for Solvent-Contaminated Wipes

Science.gov (United States)

2013-07-31

... section 307 of the Clean Water Act (CWA)); A municipal solid waste landfill that is regulated under 40 CFR... laundries and dry cleaners could dispose of sludge from cleaning solvent-contaminated wipes in solid waste landfills if the sludge does not exhibit a hazardous waste characteristic. \\8\\ The Agency stated in the...

Cleaning Process Development for Metallic Additively Manufactured Parts

Science.gov (United States)

Tramel, Terri L.; Welker, Roger; Lowery, Niki; Mitchell, Mark

2014-01-01

Additive Manufacturing of metallic components for aerospace applications offers many advantages over traditional manufacturing techniques. As a new technology, many aspects of its widespread utilization remain open to investigation. Among these are the cleaning processes that can be used for post finishing of parts and measurements to verify effectiveness of the cleaning processes. Many cleaning and drying processes and measurement methods that have been used for parts manufactured using conventional techniques are candidates that may be considered for cleaning and verification of additively manufactured parts. Among these are vapor degreasing, ultrasonic immersion and spray cleaning, followed by hot air drying, vacuum baking and solvent displacement drying. Differences in porosity, density, and surface finish of additively manufactured versus conventionally manufactured parts may introduce new considerations in the selection of cleaning and drying processes or the method used to verify their effectiveness. This presentation will review the relative strengths and weaknesses of different candidate cleaning and drying processes as they may apply to additively manufactured metal parts for aerospace applications. An ultrasonic cleaning technique for exploring the cleanability of parts will be presented along with an example using additively manufactured Inconel 718 test specimens to illustrate its use. The data analysis shows that this ultrasonic cleaning approach results in a well-behaved ultrasonic cleaning/extraction behavior. That is, it does not show signs of accelerated cavitation erosion of the base material, which was later confirmed by neutron imaging. In addition, the analysis indicated that complete cleaning would be achieved by ultrasonic immersion cleaning at approximately 5 minutes, which was verified by subsequent cleaning of additional parts.

19F NMR spectroscopy in monitoring fluorinated-solvent regeneration

International Nuclear Information System (INIS)

Ogorodnikov, V.D.; Bordunov, V.V.

1987-01-01

Extensive use is made of solvents such as trichloroethylene, freon-133, and perchloroethylene because they are good solvents for inorganic, plant, and animal greases, while the solvents can be recovered and there is no fire hazard. In this paper, the authors examined methods to monitor spent solution regeneration rapidly and with high accuracy. The authors tested perfluorinated telomeric alcohols as solvents for cleaning engineering components which have melting points of 60-120 degrees celsius. The higher working temperatures and the increased energy consumption are disadvantages of these solvents, but these are compensated for by the scope for using them virtually in the solid, liquid, and vapor states. The authors' proposed technology is based on solvents with melting points over 40 degrees celsius which produce virtually no wastes. The telomeric alcohols are recovered after cooling to normal conditions by separation from the oil by filtration and centrifugation, and they can be used in the next purification cycle. When the solvents have been regenerated, the petroleum products such as industrial oils can be reused for their original purpose. However, quantitative data are required on the solvent contents in the oil and the oil contents in the solvent in order to determine the degree of regeneration and the modes to be used. The authors have also proposed a quantitative method of determining traces of these alcohols in oils and residual oils in the solvent by fluorine NMR. All measurements were made with a BS497 NMR spectrometer

Preliminary assessment and analysis of CO2 cleaning for an inertial fusion device

International Nuclear Information System (INIS)

Ying, A.; Abdou, M.

1996-01-01

The mechanisms of cleaning with carbon dioxide ice (CO 2 ) for the National Ignition Facility (NIF) application are discussed and analyzed. The compatibility between this cleaning process and the materials proposed for energy-relevant liquid-interaction experiments is examined. The cleaning mechanisms include kinetic shear stress, sublimation followed by thermophoresis, and solvent action. The study shows that the debris size could determine the efficiency of this cleaning technique. Furthermore, if the condensed vapor particulate becomes flattened and embedded inside the abscissa while hitting the surface, a large kinetic shear would be needed for debris removal which might damage the surface. 20 refs., 5 figs

Cleaning and Restoration of an Oil Painting with a Polymer Gel in Iran

OpenAIRE

Siyamak Alizadeh

2018-01-01

One of the major stages in the conservation and restoration of a painting is to clean its colored surface of unwanted stains, and old and darkened varnishes. Various solvents have been used to date for this purpose; however, new cleaning materials have also come onto the market in the past decade that are still unknown and may never have been employed in Iran. The present study aims to introduce a polymer gel and use an in vitro sample of the substance for cleaning and to then present the res...

Extraction and identification of cyclobutanones from irradiated cheese employing a rapid direct solvent extraction method.

Science.gov (United States)

Tewfik, Ihab

2008-01-01

2-Alkylcyclobutanones (cyclobutanones) are accepted as chemical markers for irradiated foods containing lipid. However, current extraction procedures (Soxhlet-florisil chromatography) for the isolation of these markers involve a long and tedious clean-up regime prior to gas chromatography-mass spectrophotometry identification. This paper outlines an alternative isolation and clean-up method for the extraction of cyclobutanones in irradiated Camembert cheese. The newly developed direct solvent extraction method enables the efficient screening of large numbers of food samples and is not as resource intensive as the BS EN 1785:1997 method. Direct solvent extraction appears to be a simple, robust method and has the added advantage of a considerably shorter extraction time for the analysis of foods containing lipid.

Steam generator secondary side chemical cleaning at Gentilly-2

International Nuclear Information System (INIS)

Plante, S.

2006-01-01

After more than 20 years of operation, the secondary side of the four steam generators at Gentilly-2 were chemically cleaned during the 2005 annual outage. The FRAMATOME ANP high temperature cleaning process used to remove magnetite loading involved stepwise injection of solvent with PHT temperature in the range 160 o C to 175 o C. The heat required to maintain the PHT temperature was provided by the operation of the main PHT pumps and the reactor core residual heat. The temperature control was accomplished by the shutdown cooling system heat exchangers. A total of 1280 kg of magnetite was removed from the four steam generators. A copper-cleaning step was applied after the iron step. The PHT has been cooled down and the steam generators drained to temporary tanks and dried in preparation of the copper step. The process has been applied at room temperature, two boilers at a time. The solvent removed a total of 116 kg of copper. During the iron step, steam flow to the feedwater tank chemically contaminate the Balance Of Plant (BOP) systems. The isolation of this path should have been part of the G2 procedures. Around 700 m3 of water had to be drained to interim storage tanks for subsequent resin treatment before disposal. Visual inspection of BO1 tubesheet and first support plate showed clean surfaces without measurable sludge pile. Upper support plates visual inspection of BO4 revealed that broach holes blockage reported in 2000 is still present in peripheral area. Following the plant restart, the medium range level measurement instability observed since several years for BO3 was no more present. As anticipated, it also has been observed that the medium and wide range level measurements have shifted down as a result of downcomer flow increase after the cleaning. The cleaning objectives were achieved regarding the fouling reduction on the steam generators secondary side but broach holes blockage of the upper support plate is still present in periphery. (author)

Carbon steel corrosion prevention during chemical cleaning of steam generator secondary side components

International Nuclear Information System (INIS)

Fulger, M.; Lucan, D.; Velciu, L.

2009-01-01

During operation of a nuclear power plant, many contaminants, such as solid particles or dissolved species are formed in the secondary circuit, go into steam generator and deposit as scales on heat transfer tubing, support plate or as sludge on tube sheet. By accumulation of these impurities, heat transfer is reduced and the integrity of the steam generator tubing is influenced. Chemical cleaning is a qualified, efficient measure to improve steam generator corrosion performance. The corrosion mechanism can be counteracted by the chemical cleaning of the deposits on the tube sheet and the scales on the heat transfer tubing. The major component of the scales is magnetite, which can be dissolved using an organic chelating agent (ethylenediaminetetraacetic acid, EDTA) in combination with a complexing agent such as citric acid in an alkaline reducing environment. As the secondary side of SG is a conglomerate of alloys it is necessary to choose an optimal chemical cleaning solution for an efficient cleaning properties and at the same time with capability of corrosion prevention of carbon steel components during the process. The paper presents laboratory tests initiated to confirm the ability of this process to clean the SG components. The experiments followed two paths: - first, carbon steel samples have been autoclavized in specific secondary circuit solutions of steam generator to simulate the deposits constituted during operation of this equipment; - secondly, autoclavized samples have been cleaned with a solvent composed of EDTA citric acid, hydrazine of pH = 5 and temperature of 85 deg. C. Before chemical cleaning, the oxide films were characterized by surface analysis techniques including optical microscopy, scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). Applied to dissolve corrosion products formed in a steam generator, the solvents based on chelating agents are aggressive toward carbon steels and corrosion inhibitors are

Concept and properties of an infrared hybrid single-beam spectrum and its application to eliminate solvent bands and other background interferences.

Science.gov (United States)

Chen, Yujing; Wang, Hai-Shui; Morisawa, Yusuke; Ozaki, Yukihiro

2014-02-01

For infrared (IR) spectral measurements, if a quality single-beam background spectrum with desired intensity could be obtained, the contributions from solvent and other background components could be completely suppressed and their bands would not appear in a final transmittance/absorbance spectrum. In order to achieve this ideal but difficult goal, the concept of hybrid single-beam spectrum is introduced in this paper. The hybrid single-beam spectrum (φ h) is defined as a mixture of two single-beam spectra (φ b1 and φ b2) of the same sample but with different pathlengths (b1 and b2), namely, φ h = αφ b1+(1-α)φ b2, where α (0 ≤ α ≤ 1) is the component factor. The properties of the hybrid spectrum have been investigated. Under conditions of b2 > b1 ≥ 0.7 b2 and A max ≤ 0.60 (Amax is the maximum absorbance of b2 sample in the spectral range of interest), all the synthesized hybrid spectra are free from significant distortion regardless of the component factor. Therefore, the hybrid single-beam spectrum with desired intensity can be easily obtained simply by choosing an appropriate component factor. The proposed methodology has been demonstrated experimentally by the complete removal of the interference from the atmospheric water vapor and solvent. © 2013 Elsevier B.V. All rights reserved.

Recovery of uranium from 30 vol % tributyl phosphate solvents containing dibutyl phosphate

International Nuclear Information System (INIS)

Mailen, J.C.; Tallent, O.K.

1986-01-01

A number of solid sorbents were tested for the removal of uranium and dibutyl phosphate (DBP) from 30% tributyl phosphate (TBP) solvent. The desired clean uranium product can be obtained either by removing the DBP, leaving the uranium in the solvent for subsequent stripping, or by removing the uranium, leaving the DBP in the solvent for subsequent treatment. The tests performed show that it is relatively easy to preferentially remove uranium from solvents containing uranium and DBP, but quite difficult to remove DBP preferentially. The current methods could be used by removing the uranium (as by a cation exchange resin) and then using either an anion exchange resin in the hydroxyl form or a conventional treatment with a basic solution to remove the DBP. Treatment of a solvent with a cation exchange resin could be useful for recovery of valuable metals from solvents containing DBP and might be used to remove cations before scrubbing a solvent with a basic solution to minimize emulsion formation. 6 refs., 9 figs

SOLVENT-BASED TO WATERBASED ADHESIVE-COATED SUBSTRATE RETROFIT - VOLUME II: PROCESS OVERVIEW

Science.gov (United States)

This volume presents initial results of a study to identify the issues and barriers associated with retrofitting existing solvent-based equipment to accept waterbased adhesives as part of an EPA effort to improve equipment cleaning in the coated and laminated substrate manufactur...

Disposal and handling of nuclear steam generator chemical cleaning wastes

International Nuclear Information System (INIS)

Larrick, A.P.; Schneidmiller, D.

1978-01-01

A large number of pressurized water nuclear reactor electrical generating plants have experienced a corrosion-related problem with their steam generators known as denting. Denting is a mechanical deformation of the steam generator tubes that occurs at the tube support plates. Corrosion of the tube support plates occurs within the annuli through which the tubes pass and the resulting corrosion oxides, which are larger in volume than the original metal, compress and deform the tubes. In some cases, the induced stresses have been severe enough to cause tube and/or support cracking. The problem was so severe at the Turkey Point and Surrey plants that the tubing is being replaced. For less severe cases, chemical cleaning of the oxides, and other materials which deposit in the annuli from the water, is being considered. A Department of Energy-sponsored program was conducted by Consolidated Edison Co. of New York which identified several suitable cleaning solvents and led to in-plant chemical cleaning pilot demonstrations in the Indian Point Unit 1 steam generators. Current programs to improve the technology are being conducted by the Electric Power Research Institute, and the three PWR NSSS vendors with the assistance of numerous consultants, vendors, and laboratories. These programs are expected to result in more effective, less corrosive solvents. However, after a chemical cleaning is conducted, a large problem still remains- that of disposing of the spent wastes. The paper summarizes some of the methods currently available for handling and disposal of the wastes

PWR steam generator chemical cleaning, Phase I. Final report

International Nuclear Information System (INIS)

Rothstein, S.

1978-07-01

United Nuclear Industries (UNI) entered into a subcontract with Consolidated Edison Company of New York (Con Ed) on August 8, 1977, for the purpose of developing methods to chemically clean the secondary side tube to tube support crevices of the steam generators of Indian Point Nos. 1 and 2 PWR plants. This document represents the first reporting on activities performed for Phase I of this effort. Specifically, this report contains the results of a literature search performed by UNI for the purpose of determining state-of-the-art chemical solvents and methods for decontaminating nuclear reactor steam generators. The results of the search sought to accomplish two objectives: (1) identify solvents beyond those proposed at present by UNI and Con Ed for the test program, and (2) confirm the appropriateness of solvents and methods of decontamination currently in use by UNI

Anodic Oxidation of Furans in Aprotic Solvents.

Science.gov (United States)

1984-01-06

dissolved in 70 mL acetonitrile (0.003% water , K.F. titration) containing 0.1 M tetra-n-butyl ammonium tetrafluoroborate (TBAF). The solution was...solvent evaporated on a rotary evaporator at 25°C ( water bath temperature). The residue was extracted with 3 x 20 mL portions of diethylether, and the...results for a clean electrode in the same solution after presaturation with oxygen. To make the film conductive for the electrolyses , the voltage was

Influence of Solvent-Solvent and Solute-Solvent Interaction Properties on Solvent-Mediated Potential

International Nuclear Information System (INIS)

Zhou Shiqi

2005-01-01

A recently proposed universal calculational recipe for solvent-mediated potential is applied to calculate excess potential of mean force between two large Lennard-Jones (LJ) or hard core attractive Yukawa particles immersed in small LJ solvent bath at supercritical state. Comparison between the present prediction with a hypernetted chain approximation adopted for solute-solute correlation at infinitely dilute limit and existing simulation data shows high accuracy for the region with large separation, and qualitative reliability for the solute particle contact region. The calculational simplicity of the present recipe allows for a detailed investigation on the effect of the solute-solvent and solvent-solvent interaction details on the excess potential of mean force. The resultant conclusion is that gathering of solvent particles near a solute particle leads to repulsive excess PMF, while depletion of solvent particles away from the solute particle leads to attractive excess PMF, and minor change of the solvent-solvent interaction range has large influence on the excess PMF.

Energized CO{sub 2} dry ice blast cleaning firmly grounded in the Canadian electrical industry

Energy Technology Data Exchange (ETDEWEB)

Lindsay, K.

1999-02-01

Development and use of energized carbon dioxide dry ice blast technology for cleaning electrical distribution system components by Oakville Hydro and Milton Hydro (both in Ontario) is discussed. The technology was developed by Alpheus Cleaning Technologies of California and Puget Sound Power and Light Company after a two-year study that commenced in 1991, and has been supplied in Canada by Wickens Industrial Ltd., since 1993 for cleaning various industrial and non-energized electrical applications in the automotive, printing , food processing and other manufacturing industries and hydro generating facilities. The unique cleaning dynamics of this technology allow for the removal of contaminants that are much more stubborn than those encountered in pad-mounted switchgear and other electrical apparatus. Dry ice pellets, by expanding to 400 times their solid state on impact, create a flushing action that helps to remove contaminants. No grit or solvents are required and the process is non-toxic. In using the process workers wear fire retardant clothing, 40 kV-Class 4 rubber gloves and full face shields. Dielectric tests are performed routinely to confirm the dielectric integrity of the spray wand components. A two stage inspection/trouble report is completed on every job. Use of this technology eliminates power interruptions to customers, improves system reliability and safety, reduces cleaning time to a minimum, and eliminated the need for reclamation of grit or solvent containment.

Wet-cleaning of MgO(001): Modification of surface chemistry and effects on thin film growth investigated by x-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectroscopy

OpenAIRE

Le Febvrier, Arnaud; Jensen, Jens; Eklund, Per

2017-01-01

The effect of the wet-cleaning process using solvents and detergent on the surface chemistry of MgO(001) substrate for film deposition was investigated. Six different wet-cleaning processes using solvent and detergent were compared. The effect on film growth was studied by the example system ScN. The surface chemistry of the cleaned surface was studied by x-ray photoelectron spectroscopy and the film/substrate interface after film growth was investigated by time-of-flight secondary ion mass s...

Demonstration of advanced APBS solvent at TNO's CO2 capture pilot plant

NARCIS (Netherlands)

Bumb, P.; Kumar, R.; Khakharia, P.M.; Goetheer, E.L.V.

2014-01-01

The company Carbon Clean Solutions (CCS) has developed a variety of energy efficient solvents and processes such as PCCMax, which aim to reduce the overall operating and capital cost of CO2 capture. Highly successful R&D in collaboration with TNO, considering aspects from fundamental properties such

ANALYSIS ON TECHNOLOGICAL PROCESSES CLEANING OIL PIPELINES

Directory of Open Access Journals (Sweden)

Mariana PǍTRAŞCU

2015-05-01

Full Text Available In this paper the researches are presented concerning the technological processes of oil pipelines.We know several technologies and materials used for cleaning the sludge deposits, iron and manganese oxides, dross, stone, etc.de on the inner walls of drinking water pipes or industries.For the oil industry, methods of removal of waste materials and waste pipes and liquid and gas transport networks are operations known long, tedious and expensive. The main methods and associated problems can be summarized as follows: 1 Blowing with compressed air.2 manual or mechanical brushing, sanding with water or dry.3 Wash with water jet of high pressure, solvent or chemical solution to remove the stone and hard deposits.4 The combined methods of cleaning machines that use water jets, cutters, chains, rotary heads cutters, etc.

Clean Air Act Guidelines and Standards for Solvent Use and Surface Coating Industry

Science.gov (United States)

This page contains the stationary sources of air pollution for the solvent use and surface coating industries, and their corresponding air pollution regulations. To learn more about the regulations for each industry, just click on the links below.

Modern Procedures Used in Cleaning Old, Illegibly and Blackened Icons

Directory of Open Access Journals (Sweden)

Pruteanu Silvea

2015-05-01

Full Text Available In order to restore the original aesthetic aspect, to improve the state of the age patina and of the gold halo, similar processes are required. The cleaning process is one of the most important aspects for an artwork and is considering a series of deteriorations and degradations, like dirt deposits (clogged or unclogged opalescent varnish, colors blackening, burns, blisters, gaps (missing ground, painting layer or varnish. This step in the restoration process includes physical and mechanical proceedings like dusting (with a vacuum, brushing (with a brush, scraping (with a scalpel, removal or polishing etc. The scalpel and the milling process are rough unconventional means that are used only in exceptional cases. The wet cleaning of dirt includes classic washing processes, with water or other complex systems of organic solvents (emollients, surface additives or surfactants, mixtures of solvents. Cleaning the clogged dirt deposits with unconventional methods can be done by means of electronic laser, ion and thermal exchange or ultrasounds. Laser cleaning is often used in removing unwanted dirt deposits from different layers of the art piece. A lot of attention goes towards the controlled elimination of the exterior protection layer (varnish, which can be photo- degraded and oxidized by atmospheric exposure. Visual analysis, with enlargers (OM, SEM, AFM etc. combined with transmission or penetration techniques (radiography, endoscopy, X-ray diffraction etc. provides information on the superficial structures of the art work. In order to determine the modifications of the desiccant oils, SEM was used to observed the changes in the morphology of the oil painting layers. Gas chromatography/mass spectrometry (GC/MS can be used to detrmine detergent residues on the painting layer.

Hazardous Solvent Substitution Data System tutorial

International Nuclear Information System (INIS)

Twitchell, K.E.; Skinner, N.L.

1993-07-01

This manual is the tutorial for the Hazardous Solvent Substitution Data System (HSSDS), an online, comprehensive system of information on alternatives to hazardous solvents and related subjects. The HSSDS data base contains product information, material safety data sheets, toxicity reports, usage reports, biodegradable data, product chemical element lists, and background information on solvents. HSSDS use TOPIC reg-sign to search for information based on a query defined by the user. TOPIC provides a full text retrieval of unstructured source documents. In this tutorial, a series of lessons is provided that guides the user through basic steps common to most queries performed with HSSDS. Instructions are provided for both window-based and character-based applications

Accelerated solvent extraction (ASE) - a fast and automated technique with low solvent consumption for the extraction of solid samples (T12)

International Nuclear Information System (INIS)

Hoefler, F.

2002-01-01

Full text: Accelerated solvent extraction (ASE) is a modern extraction technique that significantly streamlines sample preparation. A common organic solvent as well as water is used as extraction solvent at elevated temperature and pressure to increase extraction speed and efficiency. The entire extraction process is fully automated and performed within 15 minutes with a solvent consumption of 18 ml for a 10 g sample. For many matrices and for a variety of solutes, ASE has proven to be equivalent or superior to sonication, Soxhlet, and reflux extraction techniques while requiring less time, solvent and labor. First ASE has been applied for the extraction of environmental hazards from solid matrices. Within a very short time ASE was approved by the U.S. EPA for the extraction of BNAs, PAHs, PCBs, pesticides, herbicides, TPH, and dioxins from solid samples in method 3545. Especially for the extraction of dioxins the extraction time with ASE is reduced to 20 minutes in comparison to 18 h using Soxhlet. In food analysis ASE is used for the extraction of pesticide and mycotoxin residues from fruits and vegetables, the fat determination and extraction of vitamins. Time consuming and solvent intensive methods for the extraction of additives from polymers as well as for the extraction of marker compounds from herbal supplements can be performed with higher efficiencies using ASE. For the analysis of chemical weapons the extraction process and sample clean-up including derivatization can be automated and combined with GC-MS using an online ASE-APEC-GC system. (author)

The stigma of clean dieting and orthorexia nervosa

OpenAIRE

Nevin, Suzanne M.; Vartanian, Lenny R.

2017-01-01

Background Although the stigma of eating disorders such as anorexia has been well established, little is known about the social consequences of ?clean dieting? and orthorexia nervosa. In two studies, we examined the social stigma of clean dieting and orthorexia. Method In Study 1, participants read a vignette describing a woman following a ?clean? diet, a woman with anorexia, or a control target (minimal information about the individual). In Study 2, participants read a vignette describing a ...

The ageing and poisoning of charcoal used in nuclear plant air cleaning systems

International Nuclear Information System (INIS)

Broadbent, D.

1986-01-01

Ageing and Poisoning are terms which are used to describe the in-service deterioration or weathering of activated charcoals used to remove radioiodine from air cleaning systems. This paper describes an investigation aimed at identifying the relative importance of the two effects and at comparing the resistance to weathering of potassium iodide (KI) impregnated charcoal with triethylene diamine (TEDA) impregnated charcoal. Some preliminary results are given on the rates of oxidative ageing of charcoals as a function of temperature and relative humidity. The effect on charcoal performance of organic poisons has been examined by measuring the index of performance (k-factor) of charcoals preloaded with a range of organic solvents. Finally the combined effect of oxidative ageing and organic poisoning has been measured using realistic operating conditions of temperature and relative humidity. The in-service deterioration of charcoal in air cleaning systems can be accounted for by a combination of oxidative ageing and poisoning by airborne organic solvents. (author)

Bringing Catalysis with Gold Nanoparticles in Green Solvents to Graduate Level Students

Science.gov (United States)

Raghuwanshi, Vikram Singh; Wendt, Robert; O'Neill, Maeve; Ochmann, Miguel; Som, Tirtha; Fenger, Robert; Mohrmann, Marie; Hoell, Armin; Rademann, Klaus

2017-01-01

We demonstrate here a novel laboratory experiment for the synthesis of gold nanoparticles (AuNPs) by using a low energy gold-sputtering method together with a modern, green, and biofriendly deep eutectic solvent (DES). The strategy is straightforward, economical, ecofriendly, rapid, and clean. It yields uniform AuNPs of 5 nm in diameter with high…

The EED [Emergencies Engineering Division] solvent extraction process for the removal of petroleum-derived hydrocarbons from soil

International Nuclear Information System (INIS)

Bastien, C.Y.

1994-03-01

Research was conducted to investigate the ability of hexane and natural gas condensate (NGC) to extract three different types of hydrocarbon contaminant (light crude oil, diesel fuel, and bunker C oil) from three types of soil (sand, peat, and clay). A separate but related study determined the efficiency of solvent extraction (using hexane and five other solvents but not NGC) for removal of polychlorinated biphenyls (PCB) from contaminated soil. The process developed for this research includes stages of mixing, extraction, separation, and solvent recovery, for eventual implementation as a mobile solvent extraction unit. In experiments on samples created in the laboratory, extraction efficiencies of hydrocarbons often rose above 95%. On samples from a petroleum contaminated site, average extraction efficiency was ca 82%. Sandy soils contaminated in the laboratory were effectively cleaned of all hydrocarbons tested but only diesel fuel was successfully extracted from peat soils. No significant differences were observed in the effectiveness of hexane and NGC for contamination levels above 3%. Below this number, NGC seems more effective at removing oil from peat while hexane is slightly more effective on clay soils. Sand is equally cleaned by both solvents at all contamination levels. Safety considerations, odor, extra care needed to deal with light ends and aromatics, and the fact that only 26% of the solvent is actually usable make NGC an unfeasible option in spite of its significantly lower cost compared to hexane. For extracting PCBs, a hexane/acetone mixture proved to have the best removal efficiency. 14 refs., 14 figs., 7 tabs

2727-S Nonradioactive Dangerous Waste Storage Facility clean closure evaluation report

International Nuclear Information System (INIS)

Luke, S.N.

1994-01-01

This report presents the analytical results of 2727-S NRDWS facility closure verification soil sampling and compares these results to clean closure criteria. The results of this comparison will determine if clean closure of the unit is regulatorily achievable. This report also serves to notify regulators that concentrations of some analytes at the site exceed sitewide background threshold levels (DOE-RL 1993b) and/or the limits of quantitation (LOQ). This report also presents a Model Toxics Control Act Cleanup (MTCA) (WAC 173-340) regulation health-based closure standard under which the unit can clean close in lieu of closure to background levels or LOQ in accordance with WAC 173-303-610. The health-based clean closure standard will be closure to MTCA Method B residential cleanup levels. This report reconciles all analyte concentrations reported above background or LOQ to this health-based cleanup standard. Regulator acceptance of the findings presented in this report will qualify the TSD unit for clean closure in accordance with WAC 173-303-610 without further TSD unit soil sampling, or soil removal and/or decontamination. Nondetected analytes require no further evaluation

Accumulation of solvent-soluble and solvent-insoluble antioxidant phenolics in edible bean sprouts: implication of germination

Directory of Open Access Journals (Sweden)

Ren-You Gan

2016-08-01

Full Text Available Background: Edible bean sprouts are popular fresh vegetables widely recognized for their nutritional quality. However, while their antioxidant capacity and phenolic composition in both solvent-soluble and solvent-insoluble extracts has not been systematically evaluated. Methods: The antioxidant capacity and phenolic composition in both solvent-soluble and solvent-insoluble fractions of 12 cultivars of edible bean sprouts were evaluated, and relationships of antioxidant capacity and total phenolic content were also analyzed. Results: Sprouts demonstrated a wide range of antioxidant capacity and total phenolic content, with lower but substantial antioxidant capacity and total phenolic content in the solvent-insoluble fractions. Highest levels were found in the green mung bean sprout. Phenolic compounds, such as catechin, ellagic acid, ferulic acid, gallic acid and p-coumaric acid were widely detected in these sprouts. Additionally, a positive correlation was discovered between antioxidant capacity and total phenolic content in these edible bean sprouts. Conclusions: Germination generally resulted in the accumulation of antioxidant phenolics in the most edible bean sprouts. Edible bean sprouts with high antioxidant phenolics can be valuable natural sources of dietary antioxidants for the prevention of oxidative stress-related chronic diseases.

Apparatus for reducing solvent luminescence background emissions

Energy Technology Data Exchange (ETDEWEB)

Affleck, Rhett L. (Los Alamos, NM); Ambrose, W. Patrick (Los Alamos, NM); Demas, James N. (Charlottesville, VA); Goodwin, Peter M. (Jemez Springs, NM); Johnson, Mitchell E. (Pittsburgh, PA); Keller, Richard A. (Los Alamos, NM); Petty, Jeffrey T. (Los Alamos, NM); Schecker, Jay A. (Sante Fe, NM); Wu, Ming (Los Alamos, NM)

1998-01-01

The detectability of luminescent molecules in solution is enhanced by reducing the background luminescence due to impurity species also present in the solution. A light source that illuminates the solution acts to photolyze the impurities so that the impurities do not luminesce in the fluorescence band of the molecule of interest. Molecules of interest may be carried through the photolysis region in the solution or may be introduced into the solution after the photolysis region.

Process, background and design criteria of the gas cleaning at Puertollano IGCC

Energy Technology Data Exchange (ETDEWEB)

Pisa, J. [Elcogas, Madrid (Spain)

1998-11-01

The Puertollano IGCC plant selected cooling by a water-tube boiler with upstream quenching at high velocities that requires a dust-free cooling gas at not less than 250{degree}C in order not to penalise the heat recovery efficiency. A filtration system for gas dedusting in the 250{degree}C temperature range has been installed and will be commissioned at the end of 1997. The gas cleaning concept is completed with a Venturi Scrubber, a COS hydrolysis reactor and a MDEA column to strip the sulphuric acid to yield clean gas. The gasification island is based upon the PRENFLO system which is an entrained-flow system with dry feeding. The selection of the filter system arrangement considered the limited operational experience in comparable operating conditions and acknowledged the flexibility of the filter system versus the cyclone-scrubber as far as easier load variation operation, the reduction of residues needing deposition and increased slag flow, as well as easier maintenance. Additionally to the ceramic test filters in Furstenhausen (PRENFLO) and Deer Park near Houston (SHELL), ceramic candle-type filter were selected in Buggenum and at Wabash River, and for the KoBra plant. The main criteria for the selection of the filter system and the type of candle were: separation efficiency to match clean gas limits; uniform distribution of the dust-laden gas to the filters; wear-resistant routing of the dust-laden gas flow; need for a supporting structure which must cope with sudden pressure fluctuations; optimised pulse gas system; and maintenance and repair. Based upon the above criteria, the PRENFLO concept requirements and the gas turbine specification, an arrangement with two pressure filter vessels with LLB design and filter elements manufactured by Schumacher has been installed in Puertollano. 2 figs., 3 tabs.

Exposure to organic solvents in the offset printing industry in Norway.

Science.gov (United States)

Svendsen, K; Rognes, K S

2000-03-01

The purpose of this study was to document the conditions regarding solvent exposure at offset printing offices in Norway at present and to study the variation of exposure between printing office technologies. Measurements were made at seven offset printing offices. The measurements consisted of five to 10 whole day personal exposure measurements at each office performed over a period of 2 months. Variables that may influence the level of exposure were registered by the occupational hygienist at the end of each measuring day using a check list. The influence of the variables on the "additive factor" was examined by linear regression analysis.The main contributor to the "additive factor" was isopropanol. The exposure to isopropanol sometimes exceeded the Norwegian TLV. The exposure decreased when a separate exhaust ventilation was used. The exposure increased when the machine had automatic cleaning. The variables automatic cleaning and separate exhaust ventilation explained 59% of the variation in the "additive factor". The results of this study indicate that the most important source of solvent exposure in printing offices at present is the moisturizer used in the printing machines. We think it is worth giving attention to this exposure and making efforts to reduce it.

Laser cleaning of 19th century Congo rattan mats

International Nuclear Information System (INIS)

Carmona, N.; Oujja, M.; Roemich, H.; Castillejo, M.

2011-01-01

There is a growing interest by art conservators for laser cleaning of organic materials, such as wooden artworks, paper and textiles, since traditional cleaning with solvents can be a source of further decay and mechanical cleaning may be too abrasive for sensitive fibers. In this work we present a successful laser cleaning approach for 19th century rattan mats from the Brooklyn Museum collection of African Art, now part of the study collection at the Conservation Center in New York. Tests were carried out using the fundamental (1064 nm) and second harmonic (532 nm) wavelength of a Q-switched Nd:YAG laser to measure threshold values both for surface damage and color changes for different types of rattan samples. The irradiated substrates were investigated by optical microscopy, scanning electron microscopy and by UV-vis spectroscopy in order to determine the efficiency of laser cleaning and to assess possible deterioration effects that may have occurred as a result of laser irradiation. The study showed that by using the laser emission at 532 nm, a wavelength for which photon energy is below the bond dissociation level of the main cellulosic compounds and the water absorption is negligible, it is possible to select a range of laser fluences to remove the black dust layer without damaging the rattan material.

Plasma cleaning techniques and future applications in environmentally conscious manufacturing

Energy Technology Data Exchange (ETDEWEB)

Ward, P.P.

1995-07-01

Plasmas have frequently been used in industry as a last step surface preparation technique in an otherwise predominantly wet-etch process. The limiting factor in the usefulness of plasma cleaning techniques has been the rate at which organic materials are removed. Recent research in the field of plasma chemistry has provided some understanding of plasma processes. By controlling plasma conditions and gas mixtures, ultra-fast plasma cleaning and etching is possible. With enhanced organic removal rates, plasma processes become more desirable as an environmentally sound alternative to traditional solvent or acid dominated process, not only as a cleaning tool, but also as a patterning and machining tool. In this paper, innovations in plasma processes are discussed including enhanced plasma etch rates via plasma environment control and aggressive gas mixtures. Applications that have not been possible with the limited usefulness of past plasma processes are now approaching the realm of possibility. Some of these possible applications will be discussed along with their impact to environmentally conscious manufacturing.

Manufacturing of ashless coal by using solvent de-ashing technology

Energy Technology Data Exchange (ETDEWEB)

Sang-Do Kim; Kwang-Jae Woo; Soon-Kwan Jeong; Young-Jun Rhim; Si-Huyn Lee [Korea Institute of Energy Research, Daejeon (Republic of Korea). Clean Energy Research Center

2007-07-01

Maintenance of a high oil value has an influence to energy crisis and national security in South Korea which does not have energy resources. The coals which have characterized by the abundant reserves and the inexpensive price can be said to be the alternative energy source. Hyper-coal process, which has been developed in Japan since 1999, is a new effective process to produce a clean coal by using the solvent de-ashing technology. When coal is extracted with organic solvent, only the organic portion of coal is dissolved in the solvents. That is possible to apply the low rank coal. This study was performed to produce ashless coal by using the solvent de-ashing technology. The experiment was conducted in the batch(or semi-batch) type reactor with two solvents such as NMP(N-methyl-2-pyrrolidinone) and 1-MN(1-methylnaphthalene) and various coals such as Kideko coal, Roto South coal and Sunhwa coal at 200-400{sup o}C. As a result of the test, extraction yield of coals was more than 60% on daf. Ash concentration which contains the extracted coal was 0.11-1.0wt%. The heat value was increased from 5,400 kcal/kg to 7,920 kcal/kg in the Roto South coal. 10 refs., 4 figs., 2 tabs.

The use of household cleaning products during pregnancy and lower respiratory tract infections and wheezing during early life.

Science.gov (United States)

Casas, Lidia; Zock, Jan Paul; Carsin, Anne Elie; Fernandez-Somoano, Ana; Esplugues, Ana; Santa-Marina, Loreto; Tardón, Adonina; Ballester, Ferran; Basterrechea, Mikel; Sunyer, Jordi

2013-10-01

To evaluate the effects of household use of cleaning products during pregnancy on infant wheezing and lower respiratory tract infections (LRTI). In four prospective Spanish birth cohorts (n = 2,292), pregnant women reported the use of household cleaning products. When infants were 12-18 months old, current cleaning product use and infant's wheezing and LRTI were reported. Cohort-specific associations between the use of specific products and respiratory outcomes were evaluated using multivariable regression analyses and estimates were combined using random-effects meta-analyses. The period prevalence of LRTI was higher when sprays (combined odds ratio (OR) = 1.29; 95 % confidence interval (CI) 1.04-1.59) or air fresheners (OR = 1.29; CI 1.03-1.63) were used during pregnancy. The odds of wheezing increased with spray (OR = 1.37; CI 1.10-1.69) and solvent (OR = 1.30; CI 1.03-1.62) use. The associations between spray and air freshener use during pregnancy and both outcomes remained apparent when these products were not used after pregnancy. Nevertheless, the estimates were higher when post-natal exposure was included. The use of cleaning sprays, air fresheners and solvents during pregnancy may increase the risk of wheezing and infections in the offspring.

Cleaning and Disinfection of Biofilms Composed of Listeria monocytogenes and Background Microbiota from Meat Processing Surfaces

Science.gov (United States)

Møretrø, Trond; Heir, Even; Briandet, Romain; Langsrud, Solveig

2017-01-01

ABSTRACT Surfaces of food processing premises are exposed to regular cleaning and disinfection (C&D) regimes, using biocides that are highly effective against bacteria growing as planktonic cells. However, bacteria growing in surface-associated communities (biofilms) are typically more tolerant toward C&D than their individual free-cell counterparts, and survival of pathogens such as Listeria monocytogenes may be affected by interspecies interactions within biofilms. In this study, Pseudomonas and Acinetobacter were the most frequently isolated genera surviving on conveyor belts subjected to C&D in meat processing plants. In the laboratory, Pseudomonas, Acinetobacter, and L. monocytogenes dominated the community, both in suspensions and in biofilms formed on conveyor belts, when cultures were inoculated with eleven-genus cocktails of representative bacterial strains from the identified background flora. When biofilms were exposed to daily C&D cycles mimicking treatments used in food industry, the levels of Acinetobacter and Pseudomonas mandelii diminished, and biofilms were instead dominated by Pseudomonas putida (65 to 76%), Pseudomonas fluorescens (11 to 15%) and L. monocytogenes (3 to 11%). The dominance of certain species after daily C&D correlated with high planktonic growth rates at 12°C and tolerance to C&D. In single-species biofilms, L. monocytogenes developed higher tolerance to C&D over time, for both the peracetic acid and quaternary ammonium disinfectants, indicating that a broad-spectrum mechanism was involved. Survival after C&D appeared to be a common property of L. monocytogenes strains, as persistent and sporadic subtypes showed equal survival rates in complex biofilms. Biofilms established preferentially in surface irregularities of conveyor belts, potentially constituting harborage sites for persistent contamination. IMPORTANCE In the food industry, efficient production hygiene is a key measure to avoid the accumulation of spoilage bacteria and

Cleaning and disinfection of biofilms composed of Listeria monocytogenes and background microbiota from meat processing surfaces.

Science.gov (United States)

Fagerlund, Annette; Møretrø, Trond; Heir, Even; Briandet, Romain; Langsrud, Solveig

2017-06-30

Surfaces of food processing premises are exposed to regular cleaning and disinfection (C&D) regimes, using biocides that are highly effective against bacteria growing as planktonic cells. However, bacteria growing in surface associated communities (biofilms) are typically more tolerant towards C&D than their individual free cells counterparts, and survival of pathogens such as Listeria monocytogenes may be affected by interspecies interactions within biofilms. In this study, Pseudomonas and Acinetobacter were the most frequently isolated genera surviving on conveyor belts subjected to C&D in meat processing plants. In the laboratory, Pseudomonas , Acinetobacter and L. monocytogenes dominated the community both in suspensions and in biofilms formed on conveyor belts, when cultures were inoculated with eleven-genera cocktails of representative bacterial strains from the identified background flora. When biofilms were exposed to daily C&D cycles, mimicking treatments used in food industry, the levels of Acinetobacter and Pseudomonas mandelii diminished, and biofilms were instead dominated by Pseudomonas putida (65-76%), Pseudomonas fluorescens (11-15%) and L. monocytogenes (3-11%). The dominance of certain species after daily C&D correlated with high planktonic growth rates at 12°C and tolerance to C&D. In single-species biofilms, L. monocytogenes developed higher tolerance to C&D over time, both for the peracetic acid and quaternary ammonium disinfectant, indicating that a broad-spectrum mechanism was involved. Survival after C&D appeared to be a common property of L. monocytogenes strains, as both persistent and sporadic subtypes showed equal survival in complex biofilms. Biofilms established preferentially in surface irregularities of conveyor belts, potentially constituting harborage sites for persistent contamination. IMPORTANCE In food industry, efficient production hygiene is a key measure to avoid accumulation of spoilage bacteria and eliminate pathogens

Cleaning and asthma characteristics in women.

NARCIS (Netherlands)

Dumas, O.; Siroux, V.; Luu, F.; Nadif, R.; Zock, J.P.; Kauffmann, F.; Moual, N. le

2014-01-01

Background We aimed to assess the associations between occupational exposure to cleaning products, a gender-related exposure, and asthma characteristics, considering clinical, mmunological and inflammatory aspects. Methods Analyses were conducted in 391 women (73 with adult-onset asthma) from the

Rapid, efficient and solvent free microwave mediated synthesis of aldo- and ketonitrones

Directory of Open Access Journals (Sweden)

Loredana Maiuolo

2016-01-01

Full Text Available A library of C-alkyl and C-aryl nitrones has been obtained by direct condensation of primary N-substituted hydroxylamine hydrochlorides with various aldehydes and ketones without catalysts or base. The synthetic procedure, performed under MW irradiation in the absence of solvent, does not require the presence of a base, is fast, clean, high-yielding and characterized by simple work-up.

The successful of finite element to invent particle cleaning system by air jet in hard disk drive

Science.gov (United States)

Jai-Ngam, Nualpun; Tangchaichit, Kaitfa

2018-02-01

Hard Disk Drive manufacturing has faced very challenging with the increasing demand of high capacity drives for Cloud-based storage. Particle adhesion has also become increasingly important in HDD to gain more reliability of storage capacity. The ability to clean on surfaces is more complicated in removing such particles without damaging the surface. This research is aim to improve the particle cleaning in HSA by using finite element to develop the air flow model then invent the prototype of air cleaning system to remove particle from surface. Surface cleaning by air pressure can be applied as alternative for the removal of solid particulate contaminants that is adhering on a solid surface. These technical and economic challenges have driven the process development from traditional way that chemical solvent cleaning. The focus of this study is to develop alternative way from scrub, ultrasonic, mega sonic on surface cleaning principles to serve as a foundation for the development of new processes to meet current state-of-the-art process requirements and minimize the waste from chemical cleaning for environment safety.

Synthesis of β-phenylchalcogeno-α, β-unsaturated esters, ketones and nitriles using microwave and solvent-free conditions

International Nuclear Information System (INIS)

Lenardao, Eder J.; Silva, Marcio S.; Mendes, Samuel R.; Azambuja, Francisco de; Jacob, Raquel G.; Perin, Gelson; Santos, Paulo Cesar Silva dos

2007-01-01

A simple, clean and efficient solvent-free protocol was developed for hydrochalcogenation of alkynes containing a Michael acceptor (ester, ketone and nitrile) with phenylchalcogenolate anions generated in situ from the respective diphenyl dichalcogenide (Se, Te, S), using alumina supported sodium borohydride. This efficient and improved method is general and furnishes the respective (Z)-β-phenylchalcogeno-α,β-unsaturated esters, ketones and nitriles, in good yield and higher selectivity, compared with those that use organic solvent and inert atmosphere. The use of microwave (MW) irradiation facilitates the procedure and accelerates the reaction. (author)

Cleaning of dismantled metals by electropolishing

International Nuclear Information System (INIS)

Wei, T.Y.; Chung, Z.J.; Lu, D.L.; Hsieh, J.C.

1995-01-01

A project of cleaning dismantled metals is going on at INER. The test work has been performed. Results showed that the activity decreased from 45 microSv/h to background level after 20 minutes electrolytic polishing. These cleaned metals could be reused through melting and fabricating. These metals could also be classified as BRC waste to facilitate the waste management if they can pass the identification and be admitted by the government authority. In order to achieve the planned target, some electro-decontamination facilities have been established. An automatic electropolishing facility with six cells was designed to clean the contaminated metals in plate type with dimensions less than 50 cm x 50 cm. Another automatic electropolishing facility was specially designed for treating the contaminated pipes. In addition, mobile electropolishing facilities were also established for large pieces of metal and some fixed equipment. In this cleaning project, a practical recycling and treatment method for electrolyte has been developed in order to comply with the requirement of secondary waste minimization

Solvent extraction of Southern US tar sands

Energy Technology Data Exchange (ETDEWEB)

Penney, W.R.

1990-01-01

The Department of Chemical Engineering at the University of Arkansas, in association with Diversified Petroleum Recovery, Inc. (DPR) of Little Rock, Arkansas, has been developing a solvent extraction process for the recovery of bitumen from tar sands for the past five years. The unique feature of the process is that the bitumen is recovered from the solvent by contacting with a co-solvent, which causes the bitumen to precipitate. The overall purpose of this project is to study both the technical and economic feasibility of applying this technology for recovery of bitumen from tar sands by (1) investigating the socioeconmic factors which affect (a) plant siting and (b) the market value of recovered bitumen; (2) operating a process demonstration unit at the rate of 1 lb/hr recovered bitumen while producing clean sand and recyclable solvents; and (3) determine the economic conditions which will make a bitumen recovery project economical. DPR has analyzed the historical trends of domestic production, consumption, discoveries and reserves of crude oil. They have started an investigation of the volatility in the price of crude oil and of gasoline prices and of the differential between gasoline and crude oil. DPR continues to analyze the geographical movement and demand for asphalt products. Utah does not appear economically attractive as a site for a bitumen from tar sands asphalt plant. Oklahoma sites are now being studied. This report also contains the quarterly progress report from a University of Nevada study to determine bitumen composition, oxygen uptake rates, and viscosities of Alabama and Utah bitumens. Both reports have been indexed separately for inclusion on the data base.

Determination of 21 antibiotics in sea cucumber using accelerated solvent extraction with in-cell clean-up coupled to ultra-performance liquid chromatography-tandem mass spectrometry.

Science.gov (United States)

Zhu, Minghua; Zhao, Hongxia; Xia, Deming; Du, Juan; Xie, Huaijun; Chen, Jingwen

2018-08-30

An accelerated solvent extraction (ASE) with in-cell clean-up method coupled to ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed to determine 21 antibiotics in sea cucumber. The analytes include 10 sulfonamides, 4 fluoroquinolones, 3 amphenicols, 2 beta-lactams, 1 lincosamide and trimethoprim. Optimal parameters of ASE method were obtained at 80 °C, 1 static cycle of 5 min with methanol/acetonitrile (1/1, v/v) using 2 g of C18 as adsorbent. Recoveries at 50.1-129.2% were achieved with RSD under 20%. Method detection limits ranged from 0.03 to 2.9 μg kg -1 . Compared to the reported ultrasound-assisted extraction method, the proposed method offered comparable extraction efficiency for sulfonamides from sea cucumber, but higher for other categories of antibiotics. This validated method was then successfully applied to sea cucumber samples and 9 antibiotics were detected with the highest concentration up to 57.7 μg kg -1 for norfloxacin. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effectiveness of cleaning-disinfection wipes and sprays against multidrug-resistant outbreak strains

NARCIS (Netherlands)

Kenters, N.; Huijskens, E.G.; Wit, S.C.J. de; Rosmalen, J. van; Voss, A.

2017-01-01

BACKGROUND: Hospital rooms play an important role in the transmission of several health care-associated pathogens. During the last few years, a number of innovative cleaning-disinfecting products have been brought to market. In this study, commercially available products combining cleaning and

CO{sub 2}-based supercritical fluids as environmentally-friendly processing solvents

Energy Technology Data Exchange (ETDEWEB)

Rubin, J.B.; Davenhall, L.B.; Taylor, C.M.V.; Pierce, T. [Los Alamos National Lab., NM (United States). Physical Organic Chemistry Group; Tiefert, K. [Hewlett-Packard Co., Inc., Santa Clara, CA (United States)

1999-03-01

The production of integrated circuits involves a number of discrete steps that utilize hazardous or regulated solvents. Environmental, safety and health considerations associated with these chemicals have prompted a search for alternative, more environmentally benign, solvent systems. An emerging technology for conventional solvent replacement is the use of supercritical fluids based on carbon dioxide (CO{sub 2}). Supercritical CO{sub 2} (SCCO{sub 2}) is an excellent choice for IC manufacturing processes since it is non-toxic, non-flammable, inexpensive, and is compatible with all substrate and metallizations systems. Also, conditions of temperature and pressure needed to achieve the supercritical state are easily achievable with existing process equipment. The authors first describe the general properties of supercritical fluids, with particular emphasis on their application as alternative solvents. Next, they review some of the work which has been published involving the use of supercritical fluids, and particularly CO{sub 2}, as they may be applied to the various steps of IC manufacture, including wafer cleaning, thin film deposition, etching, photoresist stripping, and waste treatment. Next, they describe the research work conducted at Los Alamos, on behalf of Hewlett-Packard, on the use of SCCO{sub 2} in a specific step of the IC manufacturing process: the stripping of hard-baked photoresist.

Self-reported occupational skin contact with cleaning agents and the risk of disability pension

DEFF Research Database (Denmark)

Feveile, Helene; Christensen, Karl Bang; Flyvholm, Mari-Ann

2009-01-01

BACKGROUND: Occupational skin diseases often affect the hands and can lead to consequences at both the individual and the social level. OBJECTIVES: To investigate and quantify the association between self-reported occupational skin contact with cleaning agents and subsequent transition to disabil......BACKGROUND: Occupational skin diseases often affect the hands and can lead to consequences at both the individual and the social level. OBJECTIVES: To investigate and quantify the association between self-reported occupational skin contact with cleaning agents and subsequent transition...... in Denmark. The Cox proportional hazards model was used to estimate the impact of occupational exposure to cleaning agents on subsequent disability pension. RESULTS: Among women, 11% of the disability pension cases were attributable to exposure to cleaning agents and/or disinfectants. CONCLUSIONS: The study...

Review of cleaning techniques and their effects on the chemical composition of foliar samples

Energy Technology Data Exchange (ETDEWEB)

Rossini Oliva, S.; Raitio, H.

2003-07-01

Chemical foliar analysis is a tool widely used to study tree nutrition and to monitor the impact and extent of air pollutants. This paper reviews a number of cleaning methods, and the effects of cleaning on foliar chemistry. Cleaning may include mechanical techniques such as the use of dry or moistened tissues, shaking, blowing, and brushing, or use various washing techniques with water or other solvents. Owing to the diversity of plant species, tissue differences, etc., there is no standard procedure for all kinds of samples. Analysis of uncleaned leaves is considered a good method for assessing the degree of air contamination because it provides an estimate of the element content of the deposits on leaf surfaces or when the analysis is aimed at the investigation of transfer of elements along the food chain. Sample cleaning is recommended in order (1) to investigate the transfer rate of chemical elements from soil to plants, (2) to qualify the washoff of dry deposition from foliage and (3) to separate superficially absorbed and biomass-incorporated elements. Since there is not a standard cleaning procedure for all kinds of samples and aims, it is advised to conduct a pilot study in order to be able to establish a cleaning procedure to provide reliable foliar data. (orig.)

Correlating Cleaning Thoroughness with Effectiveness and Briefly Intervening to Affect Cleaning Outcomes: How Clean Is Cleaned?

Directory of Open Access Journals (Sweden)

Robert Clifford

Full Text Available The most efficient approach to monitoring and improving cleaning outcomes remains unresolved. We sought to extend the findings of a previous study by determining whether cleaning thoroughness (dye removal correlates with cleaning efficacy (absence of molecular or cultivable biomaterial and whether one brief educational intervention improves cleaning outcomes.Before-after trial.Newly built community hospital.90 minute training refresher with surface-specific performance results.Dye removal, measured by fluorescence, and biomaterial removal and acquisition, measured with culture and culture-independent PCR-based assays, were clandestinely assessed for eight consecutive months. At this midpoint, results were presented to the cleaning staff (intervention and assessments continued for another eight consecutive months.1273 surfaces were sampled before and after terminal room cleaning. In the short-term, dye removal increased from 40.3% to 50.0% (not significant. For the entire study period, dye removal also improved but not significantly. After the intervention, the number of rooms testing positive for specific pathogenic species by culturing decreased from 55.6% to 36.6% (not significant, and those testing positive by PCR fell from 80.6% to 53.7% (P = 0.016. For nonspecific biomaterial on surfaces: a removal of cultivable Gram-negatives (GN trended toward improvement (P = 0.056; b removal of any cultivable growth was unchanged but acquisition (detection of biomaterial on post-cleaned surfaces that were contaminant-free before cleaning worsened (P = 0.017; c removal of PCR-based detection of bacterial DNA improved (P = 0.046, but acquisition worsened (P = 0.003; d cleaning thoroughness and efficacy were not correlated.At this facility, a minor intervention or minimally more aggressive cleaning may reduce pathogen-specific contamination, but not without unintended consequences.

Morphological control in polymer solar cells using low-boiling-point solvent additives

Science.gov (United States)

Mahadevapuram, Rakesh C.

In the global search for clean, renewable energy sources, organic photovoltaics (OPVs) have recently been given much attention. Popular modern-day OPVs are made from solution-processible, carbon-based polymers (e.g. the model poly(3-hexylthiophene) that are intimately blended with fullerene derivatives (e.g. [6,6]-phenyl-C71-butyric acid methyl ester) to form what is known as the dispersed bulk-heterojunction (BHJ). This BHJ architecture has produced some of the most efficient OPVs to date, with reports closing in on 10% power conversion efficiency. To push efficiencies further into double digits, many groups have identified the BHJ nanomorphology---that is, the phase separations and grain sizes within the polymer: fullerene composite---as a key aspect in need of control and improvement. As a result, many methods, including thermal annealing, slow-drying (solvent) annealing, vapor annealing, and solvent additives, have been developed and studied to promote BHJ self-organization. Processing organic photovoltaic (OPV) blend solutions with high-boiling-point solvent additives has recently been used for morphological control in BHJ OPV cells. Here we show that even low-boiling-point solvents can be effective additives. When P3HT:PCBM OPV cells were processed with a low-boiling-point solvent tetrahydrafuran as an additive in parent solvent o-dichlorobenzene, charge extraction increased leading to fill factors as high as 69.5%, without low work-function cathodes, electrode buffer layers or thermal treatment. This was attributed to PCBM demixing from P3HT domains and better vertical phase separation, as indicated by photoluminescence lifetimes, hole mobilities, and shunt leakage currents. Dependence on solvent parameters and applicability beyond P3HT system was also investigated.

Investigation of Alternative Approaches for Cleaning Mott Porous Metal Filters

International Nuclear Information System (INIS)

Poirier, M.R.

2003-01-01

The Department of Energy selected Caustic Side Solvent Extraction (CSSX) as the preferred cesium removal technology for Savannah River Site (SRS) waste. As a pretreatment step for the CSSX flowsheet, the incoming salt solution that contains entrained sludge is contacted with monosodium titanate (MST) to adsorb strontium and select actinides. The resulting slurry is filtered to remove the sludge and MST. Filter fouling occurs during this process. At times, personnel can increase the filtrate rate by backpulsing or scouring. At other times, the filtrate rate drops significantly and only chemical cleaning will restore filter performance. The current baseline technology for filter cleaning uses 0.5 M oxalic acid. The Salt Processing Project (SPP) at SRS, through the Tanks Focus Area, requested an evaluation of other cleaning agents to determine their effectiveness at removing trapped sludge and MST solids compared with the baseline oxalic acid method. A review of the technical literature identified compounds that appear effective at dissolving solid compounds. Consultation with the SPP management team, engineering personnel, and researchers led to a selection of oxalic acid, nitric acid, citric acid, and ascorbic acid for testing. Tests used simulated waste and actual waste as follows. Personnel placed simulated or actual SRS High Level Waste sludge and MST in a beaker. They added the selected cleaning agents, stirred the beakers, and collected supernate samples periodically analyzing for dissolved metals

Solvent selection methodology for pharmaceutical processes: Solvent swap

DEFF Research Database (Denmark)

Papadakis, Emmanouil; Kumar Tula, Anjan; Gani, Rafiqul

2016-01-01

A method for the selection of appropriate solvents for the solvent swap task in pharmaceutical processes has been developed. This solvent swap method is based on the solvent selection method of Gani et al. (2006) and considers additional selection criteria such as boiling point difference...... in pharmaceutical processes as well as new solvent swap alternatives. The method takes into account process considerations such as batch distillation and crystallization to achieve the swap task. Rigorous model based simulations of the swap operation are performed to evaluate and compare the performance...

Dry cleaning device for protective cloths for use in nuclear power plants

International Nuclear Information System (INIS)

Sugimoto, Yoshikazu.

1985-01-01

Purpose: To enable the use of fron 113 as laundry liquid so that sterilizing effect can also be attained during drying. Constitution: After cleaning various kinds of contaminations deposited to cloths in a laundry drum with fron 113 (trichlorofluoroethane), gases in the drum are recycled by a blower passing through a drying condenser and a heater to evaporize solvents or moisture content remained in the cloths. The evaporated solvent or moistures are condensated to recover when they pass through the condenser cooled by the coolants of a refrigerator. Accordingly, since high temperature drying is enabled and moistures can be dried as well by the use of fron 113, no additional provision of the drier is required and sterilizing effect can also be effected at high temperature drying. (Kamimura, M.)

Solvent extraction

Energy Technology Data Exchange (ETDEWEB)

Coombs, D.M.; Latimer, E.G.

1988-01-05

It is an object of this invention to provide for the demetallization and general upgrading of heavy oil via a solvent extracton process, and to improve the efficiency of solvent extraction operations. The yield and demetallization of product oil form heavy high-metal content oil is maximized by solvent extractions which employ either or all of the following techniques: premixing of a minor amount of the solvent with feed and using countercurrent flow for the remaining solvent; use of certain solvent/free ratios; use of segmental baffle tray extraction column internals and the proper extraction column residence time. The solvent premix/countercurrent flow feature of the invention substantially improves extractions where temperatures and pressures above the critical point of the solvent are used. By using this technique, a greater yield of extract oil can be obtained at the same metals content or a lower metals-containing extract oil product can be obtained at the same yield. Furthermore, the premixing of part of the solvent with the feed before countercurrent extraction gives high extract oil yields and high quality demetallization. The solvent/feed ratio features of the invention substanially lower the captial and operating costs for such processes while not suffering a loss in selectivity for metals rejection. The column internals and rsidence time features of the invention further improve the extractor metals rejection at a constant yield or allow for an increase in extract oil yield at a constant extract oil metals content. 13 figs., 3 tabs.

Cancer in persons working in dry cleaning in the Nordic countries.

Science.gov (United States)

Lynge, Elsebeth; Andersen, Aage; Rylander, Lars; Tinnerberg, Håkan; Lindbohm, Marja-Liisa; Pukkala, Eero; Romundstad, Pål; Jensen, Per; Clausen, Lene Bjørk; Johansen, Kristina

2006-02-01

U.S. studies have reported an increased risk of esophageal and some other cancers in dry cleaners exposed to tetrachloroethylene. We investigated whether the U.S. findings could be reproduced in the Nordic countries using a series of case-control studies nested in cohorts of laundry and dry-cleaning workers identified from the 1970 censuses in Denmark, Norway, Sweden, and Finland. Dry-cleaning work in the Nordic countries during the period when tetrachloroethylene was the dominant solvent was not associated with an increased risk of esophageal cancer [rate ratio (RR) = 0.76; 95% confidence interval (CI), 0.34-1.69], but our study was hampered by some unclassifiable cases. The risks of cancer of the gastric cardia, liver, pancreas, and kidney and non-Hodgkin lymphoma were not significantly increased. Assistants in dry-cleaning shops had a borderline significant excess risk of cervical cancer not found in women directly involved in dry cleaning. We found an excess risk of bladder cancer (RR = 1.44; 95% CI, 1.07-1.93) not associated with length of employment. The finding of no excess risk of esophageal cancer in Nordic dry cleaners differs from U.S. findings. Chance, differences in level of exposure to tetrachloroethylene, and confounding may explain the findings. The overall evidence on bladder cancer in dry cleaners is equivocal.

Supramolecular Chirality: Solvent Chirality Transfer in Molecular Chemistry and Polymer Chemistry

Directory of Open Access Journals (Sweden)

Michiya Fujiki

2014-08-01

Full Text Available Controlled mirror symmetry breaking arising from chemical and physical origin is currently one of the hottest issues in the field of supramolecular chirality. The dynamic twisting abilities of solvent molecules are often ignored and unknown, although the targeted molecules and polymers in a fluid solution are surrounded by solvent molecules. We should pay more attention to the facts that mostly all of the chemical and physical properties of these molecules and polymers in the ground and photoexcited states are significantly influenced by the surrounding solvent molecules with much conformational freedom through non-covalent supramolecular interactions between these substances and solvent molecules. This review highlights a series of studies that include: (i historical background, covering chiral NaClO3 crystallization in the presence of d-sugars in the late 19th century; (ii early solvent chirality effects for optically inactive chromophores/fluorophores in the 1960s–1980s; and (iii the recent development of mirror symmetry breaking from the corresponding achiral or optically inactive molecules and polymers with the help of molecular chirality as the solvent use quantity.

The influence of night sky background on calibration and analysis in H.E.S.S

Energy Technology Data Exchange (ETDEWEB)

Leser, Eva [Potsdam University (Germany); Collaboration: H.E.S.S. Collaboration

2016-07-01

In some regions of the galactic plane, background light by stars (night sky background) poses a severe challenge for the detection of gamma-ray sources. Thorough tests are needed to ensure a good quality of the data analysis, especially in regions with both a strong and inhomogeneous background. Investigation of the influence on calibration and data analysis is started at an early stage in data processing. Different cleaning levels were tested and the event loss rate was evaluated. It is shown that for regions with strong and inhomogeneous night sky background and a powerful source an increased cleaning level is beneficial.

Distribution of multi-component solvents in solvent vapor extraction chamber

Energy Technology Data Exchange (ETDEWEB)

Das, S. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Marathon Oil Corp., Houston, TX (United States)

2008-10-15

Vapex process performance is sensitive to operating pressures, temperatures and the types of solvent used. The hydrocarbon solvents used in Vapex processes typically have between 5 and 10 per cent hydrocarbon impurities, and the accumulation of dense phases inside the vapor chamber reduces gravity drainage potential. This study investigated the partitioning of solvent compounds inside the vapor chamber during in situ Vapex processes.The aim of the study was to examine how the different components of the mixed solvent partitioned inside the extracted chamber during the oil and vapor phase. A 2-D homogenous reservoir model was used to simulate the Vapex process with a solvent mixture comprised of propane and methane at various percentages. The effect of injecting a hot solvent vapor was also investigated. The study showed that injected methane accumulated at both the top and the extraction interface. Accumulations near the top had a positive impact on solvent confinement in thin reservoirs. Diffusion of the solvent component was controlled by gas phase molecular diffusion, and was much faster than the diffusion of solvent molecules in the liquid phase. The use of hot solvent mixtures slowed the extraction process due to lower solvent solubility in the oil phase. It was concluded that the negative impact on viscosity reduction by dilution was not compensated by rises in temperature. 6 refs., 11 figs.

Molten salt destruction of rubber and chlorinated solvents

International Nuclear Information System (INIS)

Upadhye, R.S.; Wilder, J.G.

1994-09-01

Acceptable methods for the treatment of mixed wastes are not currently available. The authors have investigated Molten Salt Destruction (MSD) as an alternative to incineration of mixed wastes. MSD differs from incineration in several ways: there is no evidence of open flames in MSD, the containment of actinides is accomplished by chemical means (wetting and dissolution), the operating temperature of MSD is much lower (700--590 C vs 1,000--1,200 C) thus lowering the volatility of actinides. Furthermore, no acid gases are released from MSD. These advantages provide the main incentive for developing MSD as an alternative to incineration. The authors have demonstrated the viability of the MSD process to cleanly destroy rubber and chlorinated solvents

Weld region corrosion during chemical cleaning of PWR [pressurized-water reactor] steam generators: Volume 2, Tests and analyses: Final report

International Nuclear Information System (INIS)

Barna, J.L.; Bozeka, S.A.; Jevec, J.M.

1987-07-01

The potential for preferential corrosion of steam generator weld regions during chemical cleaning using the generic SGOG solvents was investigated. The investigations included development and use of a corrosion assessment test facility which measured corrosion currents in a realistic model of the steam generator geometry in the vicinity of a specific weld during a simulated chemical dissolution of sludge consisting of essentially pure magnetite. A corrosion monitoring technique was developed and qualified. In this technique free corrosion rates measured by linear polarization techniques are added to corrosion rates calculated from galvanic current measured using a zero resistance ammeter to give an estimate of total corrosion rate for a galvanically corroding material. An analytic modeling technique was developed and proved useful in determining the size requirements for the weld region mockup used in the corrosion assessment test facility. The technique predicted galvanic corrosion rates consistent with that observed in a corrosion assessement test when polarization data used as model input were obtained on-line during the test. The test results obtained during this investigation indicated that chemical cleaning using the SGOG magnetite dissolution solvent can be performed with a small amount of corrosion of secondary side internals and pressure boundary welds. The maximum weld region corrosion measured during a typical chemical cleaning cycle to remove essentially pure magnetite sludge was about 8 mils. However, additional site specific weld region corrosion assessment testing and qualification will be required prior to chemical cleaning steam generators at a specific plant. Recommendations for site specific qualification of chemical cleaning processes and for use of process monitors and on-line corrosion instrumentation are included in this report

Field survey of Canadian background soils: Implications for a new mathematical gas chromatography-flame ionization detection approach for resolving false detections of petroleum hydrocarbons in clean soils.

Science.gov (United States)

Kelly-Hooper, Francine; Farwell, Andrea J; Pike, Glenna; Kennedy, Jocelyn; Wang, Zhendi; Grunsky, Eric C; Dixon, D George

2014-08-01

The reference method for the Canada-wide standard (CWS) for petroleum hydrocarbons (PHCs) in soil provides laboratories with methods for generating accurate and reproducible soil analysis results. The CWS PHC tier 1 generic soil-quality guidelines apply to 4 carbon ranges/fractions: F1 (C6-C10), F2 (C10-C16), F3 (C16-C34), and F4 (>C34). The methods and guidelines were developed and validated for soils with approximately 5% total organic carbon (TOC). However, organic soils have much higher TOC levels because of biogenic organic compounds (BOCs) originating from sources such as plant waxes and fatty acids. Coextracted BOCs can have elevated F2-F4 concentrations, which can cause false exceedances of PHC soil guidelines. The present study evaluated false PHC detections in soil samples collected from 34 background sites. The list of analytes included soil type, TOC, polycyclic aromatic hydrocarbons (PAHs), F2, F3, F4, F3a (C16-C22), and F3b (C22-C34). Soils with 3% to 41% TOC falsely exceeded the CWS PHC 300 mg/kg F3 coarse soil guideline. It was previously demonstrated that clean peat had F2:F3b ratios of less than 0.10, while crude oil spiked peat and spiked sand had higher ratios of greater than 0.10. In the present background study, all of the clean organic soils with at least 300 mg/kg F3 had F2:F3b ratios of less than 0.10, which indicated false guideline exceedances. Clean inorganic soils had low F3 concentrations, resulting in high F2:F3b ratios of greater than 0.10. Validation field studies are required to determine if the F2:F3b 0.10 PHC presence versus absence threshold value is applicable to crude oil- and diesel-contaminated sites. © 2014 SETAC.

Psychomotor Effects of Mixed Organic Solvents on Rubber Workers

Directory of Open Access Journals (Sweden)

O Aminian

2014-04-01

Full Text Available Background: Exposure to organic solvents is common among workers. Objective: To assess neurobehavioral effects of long-term exposure to organic solvents among rubber workers in Tehran, Iran. Methods: Across-sectional study was conducted on 223 employees of a rubber industry. The participants completed a data collection sheet on their occupational and medical history, and demographic characteristics including age, work experience, education level; they performed 6 psychiatric tests on the neurobehavioral core test battery (NCTB that measure simple reaction time, short-term memory (digit span, Benton, eye-hand coordination (Purdue pegboard, pursuit aiming, and perceptual speed (digit symbol. Results: Workers exposed and not exposed to organic solvents had similar age and education distribution. The mean work experience of the exposed and non-exposed workers was 5.9 and 4.4 years, respectively. The exposed workers had a lower performance compared to non-exposed workers in all psychomotor tests. After controlling for the confounders by logistic regression analysis, it was found that exposure to organic solvents had a significant effect on the results of digit symbols, digit span, Benton, aiming, and simple reaction time tests. No significant effect was observed in pegboard test. Conclusion: Occupational exposure to organic solvent can induce subtle neurobehavioral changes among workers exposed to organic solvents; therefore, periodical evaluation of the central nervous system by objective psychomotor tests is recommended among those who are chronically exposed to organic solvents.

SODIUM ALUMINOSILICATE FOULING AND CLEANING OF DECONTAMINATED SALT SOLUTION COALESCERS

International Nuclear Information System (INIS)

Poirier, M.; Thomas Peters, T.; Fernando Fondeur, F.; Samuel Fink, S.

2008-01-01

During initial non-radioactive operations at the Modular Caustic Side Solvent Extraction Unit (MCU), the pressure drop across the decontaminated salt solution coalescer reached ∼10 psi while processing ∼1250 gallons of salt solution, indicating possible fouling or plugging of the coalescer. An analysis of the feed solution and the 'plugged coalescer' concluded that the plugging was due to sodium aluminosilicate solids. MCU personnel requested Savannah River National Laboratory (SRNL) to investigate the formation of the sodium aluminosilicate solids (NAS) and the impact of the solids on the decontaminated salt solution coalescer. Researchers performed developmental testing of the cleaning protocols with a bench-scale coalescer container 1-inch long segments of a new coalescer element fouled using simulant solution. In addition, the authors obtained a 'plugged' Decontaminated Salt Solution coalescer from non-radioactive testing in the MCU and cleaned it according to the proposed cleaning procedure. Conclusions from this testing include the following: (1) Testing with the bench-scale coalescer showed an increase in pressure drop from solid particles, but the increase was not as large as observed at MCU. (2) Cleaning the bench-scale coalescer with nitric acid reduced the pressure drop and removed a large amount of solid particles (11 g of bayerite if all aluminum is present in that form or 23 g of sodium aluminosilicate if all silicon is present in that form). (3) Based on analysis of the cleaning solutions from bench-scale test, the 'dirt capacity' of a 40 inch coalescer for the NAS solids tested is calculated as 450-950 grams. (4) Cleaning the full-scale coalescer with nitric acid reduced the pressure drop and removed a large amount of solid particles (60 g of aluminum and 5 g of silicon). (5) Piping holdup in the full-scale coalescer system caused the pH to differ from the target value. Comparable hold-up in the facility could lead to less effective cleaning and

Method and apparatus for reducing solvent luminescence background emissions

Energy Technology Data Exchange (ETDEWEB)

Affleck, Rhett L. (Los Alamos, NM); Ambrose, W. Patrick (Los Alamos, NM); Demas, James N. (Charlottesville, VA); Goodwin, Peter M. (Jemez Springs, NM); Johnson, Mitchell E. (Pittsburgh, PA); Keller, Richard A. (Los Alamos, NM); Petty, Jeffrey T. (Los Alamos, NM); Schecker, Jay A. (Santa Fe, NM); Wu, Ming (Los Alamos, NM)

1998-01-01

The detectability of luminescent molecules in solution is enhanced by reducing the background luminescence due to impurity species also present in the solution. A light source that illuminates the solution acts to photolyze the impurities so that the impurities do not luminesce in the fluorescence band of the molecule of interest. Molecules of interest may be carried through the photolysis region in the solution or may be introduced into the solution after the photolysis region.

A low viscosity, low boiling point, clean solvent system for the rapid crystallisation of highly specular perovskite films

Energy Technology Data Exchange (ETDEWEB)

Noel, Nakita K.; Habisreutinger, Severin N.; Wenger, Bernard; Klug, Matthew T.; Hörantner, Maximilian T.; Johnston, Michael B.; Nicholas, Robin J.; Moore, David T.; Snaith, Henry J.

2017-01-01

Perovskite-based photovoltaics have, in recent years, become poised to revolutionise the solar industry. While there have been many approaches taken to the deposition of this material, one-step spin-coating remains the simplest and most widely used method in research laboratories. Although spin-coating is not recognised as the ideal manufacturing methodology, it represents a starting point from which more scalable deposition methods, such as slot-dye coating or ink-jet printing can be developed. Here, we introduce a new, low-boiling point, low viscosity solvent system that enables rapid, room temperature crystallisation of methylammonium lead triiodide perovskite films, without the use of strongly coordinating aprotic solvents. Through the use of this solvent, we produce dense, pinhole free films with uniform coverage, high specularity, and enhanced optoelectronic properties. We fabricate devices and achieve stabilised power conversion efficiencies of over 18% for films which have been annealed at 100 degrees C, and over 17% for films which have been dried under vacuum and have undergone no thermal processing. This deposition technique allows uniform coating on substrate areas of up to 125 cm2, showing tremendous promise for the fabrication of large area, high efficiency, solution processed devices, and represents a critical step towards industrial upscaling and large area printing of perovskite solar cells.

Optimization of the process of steel strip perforation and nickel platting for the purpose of elimination of trichloroethylene from the cleaning process of perforated steel strip

Directory of Open Access Journals (Sweden)

Petrović Aleksandra B.

2009-01-01

Full Text Available In the production of pocket type electrodes for Ni-Cd batteries perforation of proper steel strips and then nickel platting of perforated steel strips were made. In the nickel platting process, the organic solvent, trichloroethylene, has previously been used for cleaning. Due to the carcinogenic nature of trichloroethylene and the many operations previously required during cleaning, it was considered to do cleaning of perforated steel strips without use of the mentioned organic solvent. In the purpose of elimination of trichloroethylene from the cleaning process of perforated steel strips, the tests of perforation of steel strips with use of oils of different viscosity were made. It was shown that there was no dysfunction during the work of the perforation plants, meaning there was no additional heating of the strips, deterring of the steel filings, nor excessive wearing of the perforation apparatus. The perforation percent was the same irrelevant of the viscosity of the used oil. Before being perforated using the oils with different viscosity, the nickel platting steel strips were cleaned in different degreasers (based on NaOH as well as on KOH. It was shown that efficient cleaning without the use of trichloroethylene is possible with the use of oil with smaller viscosity in the perforated steel strips process and the degreaser based on KOH in the cleaning process, before nickel platting. It also appeared that the alkali degreaser based on KOH was more efficient, bath corrections were made less often and the working period of the baths was longer, which all in summary means less quantity of chemicals needed for degreasing of perforated steel strips.

Solvent wash solution

International Nuclear Information System (INIS)

Neace, J.C.

1986-01-01

This patent describes a process for removing diluent degradation products from a solvent extraction solution comprising an admixture of an organic extractant for uranium and plutonium and a non-polar organic liquid diluent, which has been used to recover uranium and plutonium from spent nuclear fuel. Comprising combining a wash solution consisting of: (a) water; and (b) a positive amount up to about, an including, 50 volume percent of at least one highly-polar water-miscible organic solvent, based on the total volume of the water and the highly-polar organic solvent, with the solvent extraction solution after uranium and plutonium values have been stripped from the solvent extraction solution, the diluent degradation products dissolving in the highly-polar organic solvent and the extractant and diluent of the extraction solution not dissolving in the highly-polar organic solvent, and separating the highly-polar organic solvent and the extraction solution to obtain a purified extraction solution

Planck early results. XVIII. The power spectrum of cosmic infrared background anisotropies

DEFF Research Database (Denmark)

Poutanen, T.; Natoli, P.; Polenta, G.

2011-01-01

Using Planck maps of six regions of low Galactic dust emission with a total area of about 140 deg2, we determine the angular power spectra of cosmic infrared background (CIB) anisotropies from multipole = 200 to = 2000 at 217, 353, 545 and 857 GHz. We use 21-cm observations of Hi as a tracer...... of thermal dust emission to reduce the already low level of Galactic dust emission and use the 143 GHz Planck maps in these fields to clean out cosmic microwave background anisotropies. Both of these cleaning processes are necessary to avoid significant contamination of the CIB signal. We measure correlated...

ASAView: Database and tool for solvent accessibility representation in proteins

Directory of Open Access Journals (Sweden)

Fawareh Hamed

2004-05-01

Full Text Available Abstract Background Accessible surface area (ASA or solvent accessibility of amino acids in a protein has important implications. Knowledge of surface residues helps in locating potential candidates of active sites. Therefore, a method to quickly see the surface residues in a two dimensional model would help to immediately understand the population of amino acid residues on the surface and in the inner core of the proteins. Results ASAView is an algorithm, an application and a database of schematic representations of solvent accessibility of amino acid residues within proteins. A characteristic two-dimensional spiral plot of solvent accessibility provides a convenient graphical view of residues in terms of their exposed surface areas. In addition, sequential plots in the form of bar charts are also provided. Online plots of the proteins included in the entire Protein Data Bank (PDB, are provided for the entire protein as well as their chains separately. Conclusions These graphical plots of solvent accessibility are likely to provide a quick view of the overall topological distribution of residues in proteins. Chain-wise computation of solvent accessibility is also provided.

Determination of cosmic ray produced radionuclides by means of background radiation counting system, 3

International Nuclear Information System (INIS)

1976-01-01

This is the third report of the progress report series on studies of cosmic ray produced radionuclides by means of low background radiation counting system. In Part I some characteristics of a low beta-gamma coincidence spectrometer are described -- counter system, electronics, background spectra, counting efficiencies -- and studies on radioactive impurities in materials for scientific research are also described. In Part II, suitable solvents for a large scale liquid scintillation counter were examined and best combinations of solvents, solutes and naphthalene are shown. In Part III, miscellaneous topics are reported. (auth.)

Caustic-Side Solvent Extraction Chemical and Physical Properties Progress in FY 2000 and FY 2001.

Energy Technology Data Exchange (ETDEWEB)

Moyer, BA

2002-04-17

The purpose of this work was to provide chemical- and physical-property data addressing the technical risks of the Caustic-Side Solvent Extraction (CSSX) process as applied specifically to the removal of cesium from alkaline high-level salt waste stored at the US Department of Energy Savannah River Site. As part of the overall Salt Processing Project, this effort supported decision-making in regards to selecting a preferred technology among three alternatives: (1) CSSX, (2) nonelutable ion-exchange with an inorganic silicotitanate material and (3) precipitation with tetraphenylborate. High risks, innate to CSSX, that needed specific attention included: (1) chemical stability of the solvent matrix, (2) radiolytic stability of the solvent matrix, (3) proof-of-concept performance of the proposed process flowsheet with simulated waste, and (4) performance of the CSSX flowsheet with actual SRS high-level waste. This body of work directly addressed the chemical-stability risk and additionally provided supporting information that served to plan, carry out, and evaluate experiments conducted by other CSSX investigators addressing the other high risks. Information on cesium distribution in extraction, scrubbing, and stripping served as input for flowsheet design, provided a baseline for evaluating solvent performance under numerous stresses, and contributed to a broad understanding of the effects of expected process variables. In parallel, other measurements were directed toward learning how other system components distribute in the flowsheet. Such components include the solvent components themselves, constituents of the waste, and solvent-degradation products. Upon understanding which components influence flowsheet performance, it was then possible to address in a rational fashion how to clean up the solvent and maintain its stable function.

Response of solvent-exposed printers and unexposed controls to six-hour toluene exposure

DEFF Research Database (Denmark)

Bælum, Jesper; Andersen, I B; Lundqvist, G R

1985-01-01

of intoxication, and irritation of the eyes, nose and throat. Furthermore, the subjects exposed to toluene showed decreased manual dexterity, decreased color discrimination, and decreased accuracy in visual perception. There was no significant difference in the effects of toluene on printers compared to those......The acute effects of toluene were studied in 43 male printers and 43 control subjects matched according to sex, age, educational level, and smoking habits. The mean age of the subjects was 36 (range 29-50) years. The printers had been exposed to solvents for 9 to 25 years during employment at flexo...... and rotogravure printing plants, while the controls had no history of solvent exposure. Each subject was exposed once in a climate chamber to either 100 ppm of toluene or clean air for 6.5 h preceded by a 1-h acclimatization period. The effects of toluene were measured from subjective votes with linear analogue...

Oil-in-water nanocontainers as low environmental impact cleaning tools for works of art: two case studies.

Science.gov (United States)

Carretti, Emiliano; Giorgi, Rodorico; Berti, Debora; Baglioni, Piero

2007-05-22

A novel class of p-xylene-in-water microemulsions mainly based on nonionic surfactants and their application as low impact cleaning tool in cultural heritage conservation is presented. Alkyl polyglycosides (APG) and Triton X-100 surfactants allow obtaining very effective low impact oil-in-water (o/w) microemulsions as alternatives to pure organic solvents for the removal of polymers (particularly Paraloid B72 and Primal AC33) applied during previous conservation treatments. The ternary APG/p-xylene/water microemulsions have been characterized by quasi elastic light scattering to obtain the hydrodynamic radius and the polydispersity of the microemulsion droplets. Laplace inversion of the correlation function CONTIN analysis provided evidence of acrylic copolymers solubilization into the oil nanodroplets. Contact angle, Fourier transform infrared (FTIR), and scanning electron microscopy/energy-dispersive spectroscopy (SEM/EDS) data confirmed that microemulsions were effective in removing polymer coatings. The phase diagram of APG microemulsions showed that a reduction >90% (compared to the conventional cleaning methods) of the organic solvent can be achieved by using o/w microemulsions. The microemulsions were successfully tested in two real cases: (1) the APG based microemulsion was used in a Renaissance painting by Vecchietta in Santa Maria della Scala, Siena, Italy, degraded by the presence of a polyacrylate coating applied during a previous restoration and (2) a Triton X-100 oil-in-water microemulsion containing (NH4)2CO3 in the water continuous phase. The association of ammoniun carbonate to the microemusion led to the swelling of an organic deposit (mainly asphaltenes deposited on the fresco in the Oratorio di San Nicola al Ceppo in Florence, still contamined by the water of the Arno river during the 1966 flood) and a very efficient removal of highly insoluble inorganic deposits (mainly gypsum) strongly associated to asphaltenes. These innovative systems are

Solvent extraction of Zn and metals in Zn ores by nonphosphorous solvents

International Nuclear Information System (INIS)

Auchapt, J.M.; Tostain, Jacqueline.

1975-07-01

This bibliography follows a first work on Zn solvent extraction by organo-phosphorous compounds. The other solvents used in Zn extraction, are studied: oxygenated nonphosphorous solvents (ketones, alcohols, carboxylic acids, sulfonates), nitrogenous solvents and hydrocarbons [fr

Controlling the cost of clean air - A new clean coal technology

International Nuclear Information System (INIS)

Kindig, J.K.; Godfrey, R.L.

1991-01-01

This article presents the authors' alternative to expensive coal combustion products clean-up by cleaning the coal, removing the sulfur, before combustion. Topics discussed include sulfur in coal and the coal cleaning process, the nature of a new coal cleaning technology, the impact on Clean Air Act compliance, and the economics of the new technology

Quantitative assessment of airborne exposures generated during common cleaning tasks: a pilot study

Directory of Open Access Journals (Sweden)

Perry Melissa J

2010-11-01

Full Text Available Abstract Background A growing body of epidemiologic evidence suggests an association between exposure to cleaning products with asthma and other respiratory disorders. Thus far, these studies have conducted only limited quantitative exposure assessments. Exposures from cleaning products are difficult to measure because they are complex mixtures of chemicals with a range of physicochemical properties, thus requiring multiple measurement techniques. We conducted a pilot exposure assessment study to identify methods for assessing short term, task-based airborne exposures and to quantitatively evaluate airborne exposures associated with cleaning tasks simulated under controlled work environment conditions. Methods Sink, mirror, and toilet bowl cleaning tasks were simulated in a large ventilated bathroom and a small unventilated bathroom using a general purpose, a glass, and a bathroom cleaner. All tasks were performed for 10 minutes. Airborne total volatile organic compounds (TVOC generated during the tasks were measured using a direct reading instrument (DRI with a photo ionization detector. Volatile organic ingredients of the cleaning mixtures were assessed utilizing an integrated sampling and analytic method, EPA TO-17. Ammonia air concentrations were also measured with an electrochemical sensor embedded in the DRI. Results Average TVOC concentrations calculated for 10 minute tasks ranged 0.02 - 6.49 ppm and the highest peak concentrations observed ranged 0.14-11 ppm. TVOC time concentration profiles indicated that exposures above background level remained present for about 20 minutes after cessation of the tasks. Among several targeted VOC compounds from cleaning mixtures, only 2-BE was detectable with the EPA method. The ten minute average 2- BE concentrations ranged 0.30 -21 ppm between tasks. The DRI underestimated 2-BE exposures compared to the results from the integrated method. The highest concentration of ammonia of 2.8 ppm occurred

Characterization of Cleaning and Disinfecting Tasks and Product Use Among Hospital Occupations

Science.gov (United States)

Saito, Rena; Virji, M. Abbas; Henneberger, Paul K.; Humann, Michael J.; LeBouf, Ryan F.; Stanton, Marcia L.; Liang, Xiaoming; Stefaniak, Aleksandr B.

2016-01-01

Background Healthcare workers have an elevated prevalence of asthma and related symptoms associated with the use of cleaning/disinfecting products. The objective of this study was to identify and characterize cleaning/disinfecting tasks and products used among hospital occupations. Methods Workers from 14 occupations at five hospitals were monitored for 216 shifts, and work tasks and products used were recorded at five-minute intervals. The major chemical constituents of each product were identified from safety data sheets. Results Cleaning and disinfecting tasks were performed with a high frequency at least once per shift in many occupations. Medical equipment preparers, housekeepers, floor strippers/waxers, and endoscopy technicians spent on average 108–177 min/shift performing cleaning/disinfecting tasks. Many occupations used products containing amines and quaternary ammonium compounds for > 100 min/shift. Conclusions This analysis demonstrates that many occupations besides housekeeping incur exposures to cleaning/disinfecting products, albeit for different durations and using products containing different chemicals. PMID:25351791

Solvent/Non-Solvent Sintering To Make Microsphere Scaffolds

Science.gov (United States)

Laurencin, Cato T.; Brown, Justin L.; Nair, Lakshmi

2011-01-01

A solvent/non-solvent sintering technique has been devised for joining polymeric microspheres to make porous matrices for use as drug-delivery devices or scaffolds that could be seeded with cells for growing tissues. Unlike traditional sintering at elevated temperature and pressure, this technique is practiced at room temperature and pressure and, therefore, does not cause thermal degradation of any drug, protein, or other biochemical with which the microspheres might be loaded to impart properties desired in a specific application. Also, properties of scaffolds made by this technique are more reproducible than are properties of comparable scaffolds made by traditional sintering. The technique involves the use of two miscible organic liquids: one that is and one that is not a solvent for the affected polymer. The polymeric microspheres are placed in a mold having the size and shape of the desired scaffold, then the solvent/non-solvent mixture is poured into the mold to fill the void volume between the microspheres, then the liquid mixture is allowed to evaporate. Some of the properties of the resulting scaffold can be tailored through choice of the proportions of the liquids and the diameter of the microspheres.

Chemical cleaning/disinfection and ageing of organic UF membranes: a review.

Science.gov (United States)

Regula, C; Carretier, E; Wyart, Y; Gésan-Guiziou, G; Vincent, A; Boudot, D; Moulin, P

2014-06-01

Membrane separation processes have become a basic unit operation for process design and product development. These processes are used in a variety of separation and concentration steps, but in all cases, the membranes must be cleaned regularly to remove both organic and inorganic material deposited on the surface and/or into the membrane bulk. Cleaning/disinfection is a vital step in maintaining the permeability and selectivity of the membrane in order to get the plant to its original capacity, to minimize risks of bacteriological contamination, and to make acceptable products. For this purpose, a large number of chemical cleaning/disinfection agents are commercially available. In general, these cleaning/disinfection agents have to improve the membrane flux to a certain extent. However, they can also cause irreversible damages in membrane properties and performances over the long term. Until now, there is considerably less literature dedicated to membrane ageing than to cleaning/disinfection. The knowledge in cleaning/disinfection efficiency has recently been improved. But in order to develop optimized cleaning/disinfection protocols there still remains a challenge to better understand membrane ageing. In order to compensate for the lack of correlated cleaning/disinfection and ageing data from the literature, this paper investigates cleaning/disinfection efficiencies and ageing damages of organic ultrafiltration membranes. The final aim is to provide less detrimental cleaning/disinfection procedures and to propose some guidelines which should have been taken into consideration in term of membrane ageing studies. To carry out this study, this article will detail the background of cleaning/disinfection and aging membrane topics in a first introductive part. In a second part, key factors and endpoints of cleaning/disinfection and aging membranes will be discussed deeply: the membrane role and the cleaning parameters roles, such as water quality, storing conditions

Solvents and solvent effects in organic chemistry

National Research Council Canada - National Science Library

Reichardt, C; Welton, T

2011-01-01

.../guest complexation equilibria and reactions in biphasic solvent systems and neoteric solvents, respectively. More than 900 new references have been added, giving preference to review articles, and many older ones have been deleted. New references either replace older ones or are added to the end of the respective reference list of each chapter. Th...

Caustic-Side Solvent Extraction: Chemical and Physical Properties of the Optimized Solvent

Energy Technology Data Exchange (ETDEWEB)

Delmau, L.H.

2002-10-08

This work was undertaken to optimize the solvent used in the Caustic Side Solvent Extraction (CSSX) process and to measure key chemical and physical properties related to its performance in the removal of cesium from the alkaline high-level salt waste stored in tanks at the Savannah River Site. The need to adjust the solvent composition arose from the prior discovery that the previous baseline solvent was supersaturated with respect to the calixarene extractant. The following solvent-component concentrations in Isopar{reg_sign} L diluent are recommended: 0.007 M calix[4]arene-bis(tert-octylbenzo-crown-6) (BOBCalixC6) extractant, 0.75 M 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB) phase modifier, and 0.003 M tri-n-octylamine (TOA) stripping aid. Criteria for this selection included BOBCalixC6 solubility, batch cesium distribution ratios (D{sub Cs}), calculated flowsheet robustness, third-phase formation, coalescence rate (dispersion numbers), and solvent density. Although minor compromises within acceptable limits were made in flowsheet robustness and solvent density, significant benefits were gained in lower risk of third-phase formation and lower solvent cost. Data are also reported for the optimized solvent regarding the temperature dependence of D{sub Cs} in extraction, scrubbing, and stripping (ESS); ESS performance on recycle; partitioning of BOBCalixC6, Cs-7SB, and TOA to aqueous process solutions; partitioning of organic anions; distribution of metals; solvent phase separation at low temperatures; solvent stability to elevated temperatures; and solvent density and viscosity. Overall, the technical risk of the CSSX process has been reduced by resolving previously identified issues and raising no new issues.

[Myelofibrosis in a benzene-exposed cleaning worker].

Science.gov (United States)

Bausà, Roser; Navarro, Lydia; Cortès-Franch, Imma

Long-term exposure to benzene has been associated with several blood malignancies, including aplastic anemia, myeloproliferative neoplasms, and different leukemias. We present a case of primary myelofibrosis in a 59-year-old woman who worked as a cleaner at a car dealership and automobile mechanic shop. For 25 years, she used gasoline as a degreaser and solvent to clean engine parts, floors and work desks on a daily basis. She was referred by her primary care provider to the Occupational Health Unit of Barcelona to assess whether her illness was work-related. Review of her job history and working conditions revealed chronic exposure to benzene in the absence of adequate preventive measures. An association between benzene exposure and myeloproliferative disease was established, suspicious for an occupational disease. Copyright belongs to the Societat Catalana de Salut Laboral.

Performances in Tank Cleaning

Directory of Open Access Journals (Sweden)

Fanel-Viorel Panaitescu

2018-03-01

Full Text Available There are several operations which must do to maximize the performance of tank cleaning. The new advanced technologies in tank cleaning have raised the standards in marine areas. There are many ways to realise optimal cleaning efficiency for different tanks. The evaluation of tank cleaning options means to start with audit of operations: how many tanks require cleaning, are there obstructions in tanks (e.g. agitators, mixers, what residue needs to be removed, are cleaning agents required or is water sufficient, what methods can used for tank cleaning. After these steps, must be verify the results and ensure that the best cleaning values can be achieved in terms of accuracy and reliability. Technology advancements have made it easier to remove stubborn residues, shorten cleaning cycle times and achieve higher levels of automation. In this paper are presented the performances in tank cleaning in accordance with legislation in force. If tank cleaning technologies are effective, then operating costs are minimal.

The chemistry of nonaqueous solvents v.4 solution phenomena and aprotic solvents

CERN Document Server

Lagowski, J J

1976-01-01

The Chemistry of Nonaqueous Solvents, Volume IV: Solution Phenomena and Aprotic Solvents focuses on the chemistry of nonaqueous solvents, with emphasis on solution phenomena and aprotic solvents such as tetramethylurea, inorganic acid chlorides, cyclic carbonates, and sulfolane. This book is organized into seven chapters and begins with an overview of the theory of electrical conductivity and elementary experimental considerations, along with some of the interesting research on nonaqueous solvents. It then turns to a discussion on hydrogen bonding phenomena in nonaqueous systems as probed

Clean Cities Fact Sheet

Energy Technology Data Exchange (ETDEWEB)

2004-01-01

This fact sheet explains the Clean Cities Program and provides contact information for all coalitions and regional offices. It answers key questions such as: What is the Clean Cities Program? What are alternative fuels? How does the Clean Cities Program work? What sort of assistance does Clean Cities offer? What has Clean Cities accomplished? What is Clean Cities International? and Where can I find more information?

A solvent/non-solvent system for achieving solution-processed multilayer organic light-emitting devices

Energy Technology Data Exchange (ETDEWEB)

Yu, Yue; Wu, Zhaoxin, E-mail: zhaoxinwu@mail.xjtu.edu.cn; He, Lin; Jiao, Bo; Hou, Xun

2015-08-31

We developed a solvent/non-solvent system to fabricate the multilayer organic light-emitting devices (OLEDs) based on poly(N-vinylcarbazole) (PVK) by solution-process. This solvent system consists of both the solvent and non-solvent of PVK, in which fluorescent small molecules could be fully dissolved and directly spin-coated on top of the PVK layer; it could effectively avoid the redissolution of PVK during the spin-coating process of small molecules emitting layer. In the further investigation of this system, we also demonstrated the three-component solvent system, and found out that the third component, a less volatile solvent of PVK, was crucial for preparing a smoother interface between PVK and emitting layer. Compared with OLEDs through the vacuum deposition, the devices fabricated by solution-process from the solvent/non-solvent system showed comparable efficiency, which indicate that the solvent/non-solvent system can be used as an alternative process to prepare the polymer and small molecule multilayer devices through all-solution-process. - Highlights: • We fabricate the multilayer OLEDs by solution-process using a novel system. • We develop a solvent/non-solvent system of polymer (PVK) to avoid redissolution. • Small molecules could be fully dissolved and directly spin-coated on PVK layer. • The devices fabricated by the system and vacuum deposition show comparable efficiency.

Laser surface cleaning

International Nuclear Information System (INIS)

Freiwald, J.G.; Freiwald, D.A.

1994-01-01

The objective of this work is a laboratory demonstration that red-lead primer and two-part epoxy paints can be stripped from concrete and metal surfaces using surface cleaning systems based on pulsed-repetition CO 2 lasers. The three goals are to: (1) demonstrate coatings removal, including surface pore cleaning; (2) demonstrate that there is negligible release of ablated contaminants to the environment; and (3) demonstrate that the process will generate negligible amounts of additional waste compared to competing technologies. Phase 1 involved site visits to RMI and Fernald to assess the cleaning issues for buildings and parts. In addition, Phase 1 included detailed designs of a more powerful system for industrial cleaning rates, including laser, articulating optics, ablated-material capture suction nozzle attached to a horizontal raster scanner for floor cleaning, and filtration system. Some concept development is also being done for using robots, and for parts cleaning. In Phase 2 a transportable 6 kW system will be built and tested, with a horizontal surface scanner for cleaning paint from floors. The laboratory tests will again be instrumented. Some concept development will continue for using robots, and for parts cleaning. This report describes Phase 1 results

Ultra-clean

International Nuclear Information System (INIS)

Hergenroether, K.

1987-01-01

No other method guarantees such a thorough cleaning of contaminated materials' surfaces. Only ultrasound can reach those cavities crevices and corners where any manual cleaning fails. Furthermore there is no cumbersome and time-consuming manual decontamination which often has to be carried out in glove boxes and hot cells. Depending on the design the cleaning effect can reach from removing adhering dirt particles to removing complete surface layers. (orig./PW) [de

Clean Energy Solutions Center: Assisting Countries with Clean Energy Policy

Science.gov (United States)

advice on financing instruments. In a recent keynote to the Climate and Clean Energy Investment Forum renewable energy technologies in the country. Informing Energy Access and Clean Energy Project Finance understanding and knowledge of how to design policies that enable financing and encourage investment in clean

studies on solvent extraction of free hydrogen cyanide from river water

African Journals Online (AJOL)

A method for free and strongly complexed cyanide measurement in river water was developed. Recovery tests from solution with and without river water, using various solvent combinations and background control were investigated to obtain an accurate and precise extraction method for the measurement of hydrogen ...

Effectiveness of Surface Cleaning and Disinfection in a Brazilian Healthcare Facility

Science.gov (United States)

Santos-Junior, Aires G.; Ferreira, Adriano M.; Frota, Oleci P.; Rigotti, Marcelo A.; Barcelos, Larissa da S.; Lopes de Sousa, Alvaro Francisco; de Andrade, Denise; Guerra, Odanir G.; R. Furlan, Mara C.

2018-01-01

Background: Failures in the processes of cleaning and disinfecting health service surfaces may result in the spread and transfer of pathogens that are often associated with healthcare-related infections and outbreaks. Aims: To assess the effectiveness of environmental surface cleaning and disinfection in a hospital clinic. Method: The study was conducted in a nursing ward with 45 beds. A total of 80 samples from five high-touch surfaces were evaluated before and after cleaning and disinfection, using the following methods: visual inspection, adenosine triphosphate bioluminescence assay, aerobic colony count, Staphylococcus aureus colony count, and evaluation of resistance to methicillin. The data analysis used nonparametric comparative and correlative tests to observe any differences in the pre- and post- cleaning and disinfection results for the surfaces assessed. Results: Effective cleaning and disinfection had a significant effect on only two surfaces when measured for the presence of adenosine triphosphate, the inner bathroom door handle (p=0.007) and the toilet bowl (p=0.01). When evaluated for Staphylococcus aureus colony count, the toilet flush handle also demonstrated a significant effect (p=0.04). Conclusion: The effectiveness of cleaning and disinfection of the surfaces tested was not satisfactory. An educational intervention is recommended for the cleaning and disinfection staff and the nursing team at the healthcare facility. Relevance to Clinical Practice: The data in the study revealed that daily hospital cleaning and disinfection in the sampled sites are not sufficient in medical and surgical wards. Hospital cleanliness must be reevaluated from the point of view of materials, such as an adequate supply of clean cloths, in addition to establishing more precise cleanliness protocols and accurate monitoring systems. PMID:29643951

Chemical cleaning of nuclear (PWR) steam generators

International Nuclear Information System (INIS)

Welty, C.S. Jr.; Mundis, J.A.

1982-01-01

This paper reports on a significant research program sponsored by a group of utilities (the Steam Generator Owners Group), which was undertaken to develop a process to chemically remove corrosion product deposits from the secondary side of pressurized water reactor (PWR) power plant steam generators. Results of this work have defined a process (solvent system and application methods) that is capable of removing sludge and tube-to-tube support plate crevice corrosion products generated during operation with all-volatile treatment (AVT) water chemistry. Considers a plant-specific test program that includes all materials in the steam generator to be cleaned and accounts for the physical locations (proximity and contact) of those materials. Points out that prior to applying the process in an operational unit, the utility, with the participation of the NSSR vendor, must define allowable total corrosion to the materials of construction of the unit

Analysis of solvent extracts from coal liquefaction in a flowing solvent reactor

Energy Technology Data Exchange (ETDEWEB)

Li, Wen-Ying; Feng, Jie; Xie, Ke-Chang [Key Laboratory of Coal Science and Technology, Taiyuan University of Technology, Ministry of Education and Shanxi Province, No. 79 Yingze West Street, Taiyuan 030024 (China); Kandiyoti, R. [Department of Chemical Engineering and Chemical Technology, Imperial College, University of London, London SW7 2BY (United Kingdom)

2004-10-15

Point of Ayr coal has been extracted using three solvents, tetralin, quinoline and 1-methyl-2-pyrrolidinone (NMP) at two temperatures 350 and 450 C, corresponding approximately to before and after the onset of massive covalent bond scission by pyrolysis. The three solvents differ in solvent power and the ability to donate hydrogen atoms to stabilise free radicals produced by pyrolysis of the coal. The extracts were prepared in a flowing solvent reactor to minimise secondary thermal degradation of the primary extracts. Analysis of the pentane-insoluble fractions of the extracts was achieved by size exclusion chromatography, UV-fluorescence spectroscopy in NMP solvent and probe mass. With increasing extraction temperature, the ratio of the amount having big molecular weight to that having small molecular weight in tetralin extracts was increased; the tetralin extract yield increased from 12.8% to 75.9%; in quinoline, increasing extraction temperature did not have an effect on the molecular weight of products but there was a big increase in extract yield. The extracts in NMP showed the enhanced solvent extraction power at both temperatures, with a shift in the ratio of larger molecules to smaller molecules with increasing extraction temperature and with the highest conversion of Point of Ayr coal among these three solvents at both temperatures. Solvent adducts were detected in the tetralin and quinoline extracts by probe mass spectrometry; solvent products were formed from NMP at both temperatures.

How clean is clean?---How clean is needed?

International Nuclear Information System (INIS)

Hays, A.K.

1991-01-01

This paper will provide an overview of cleaning qualifications used in a variety of industries: from small-scale manufacturer's of precision-machined products to large-scale manufacturer's of electronics (printed wiring boards and surface mount technology) and microelectronics. Cleanliness testing techniques used in the production of precision-machined products, will be described. The on-going DOD program to obtain high-reliability electronics, through the use of military specifications for cleaning and cleanliness levels, will be reviewed. In addition, the continually changing cleanroom/materials standards of the microelectronics industry will be discussed. Finally, we will speculate on the role that new and improved analytical techniques and sensor technologies will play in the factories of the future. 4 refs., 1 tab

Innovative eco-friendly bio- solvent for combating sea surface and sedimented oil pollution

Science.gov (United States)

Theodorou, Paraskevas

2017-04-01

The combating of oil spill at sea surface by chemical dispersants accelerates the evaporation and disperse the oil into the water column, where it is broken down by natural processes and/or is sedimented at the sea bottom, especially at near coastal shallow areas, ports and marinas. The usual methodology for cleaning the sedimented oil from the sea bottom is mainly carried out via excavation and dumping of the polluted sediment into deeper sea areas, where the contamination is transferred from one area to another. The eco-friendly bio-solvent MSL Aqua 250 is an innovative new solution based mainly on natural constituents. The action mechanism and the effectiveness of this eco-friendly solvent is based on the high surface tension process. Organic compounds, including hydrocarbons upon coming in contact with MSL Aqua 250 solvent generate a significant surface tension reaction, which is able to alter the organic compounds to liquid form and then to drastically evaporate it. The use of MSL Aqua 250 solvent, both at sea surface and at the bottom, has the following advantages compared to the dispersants: • Efficient solution without transferring the pollution from sea surface to the water column and to the bottom or disturbing the Aquatic Eco System. • Non-Toxic. • Environmentally friendly with a restoration of marine life in the Eco System. • Cost effective. The MSL Aqua 250 solvent has been tested in cooperation with the Cyprus Department of Fisheries and Marine Research and the Technological University of Cyprus and used during the years 2015 and 2016 in marinas and fishing shelters in Cyprus faced oil pollution, with high concentration in the sea water and at the sea bottom of chemical parameters (BOD5, COD, FOG, TKN, TP, TPH), with excellent results.

The Solvent Selection framework: solvents for organic synthesis, separation processes and ionic-organic synthesis

DEFF Research Database (Denmark)

Mitrofanov, Igor; Sansonetti, Sascha; Abildskov, Jens

2012-01-01

This paper presents a systematic integrated framework for solvent selection and solvent design. The framework is divided into several modules, which can tackle specific problems in various solvent-based applications. In particular, three modules corresponding to the following solvent selection pr...

Nanomaterials for the cleaning and pH adjustment of vegetable-tanned leather

Science.gov (United States)

Baglioni, Michele; Bartoletti, Angelica; Bozec, Laurent; Chelazzi, David; Giorgi, Rodorico; Odlyha, Marianne; Pianorsi, Diletta; Poggi, Giovanna; Baglioni, Piero

2016-02-01

Leather artifacts in historical collections and archives are often contaminated by physical changes such as soiling, which alter their appearance and readability, and by chemical changes which occur on aging and give rise to excessive proportion of acids that promote hydrolysis of collagen, eventually leading to gelatinization and loss of mechanical properties. However, both cleaning and pH adjustment of vegetable-tanned leather pose a great challenge for conservators, owing to the sensitivity of these materials to the action of solvents, especially water-based formulations and alkaline chemicals. In this study, the cleaning of historical leather samples was optimized by confining an oil-in-water nanostructured fluid in a highly retentive chemical hydrogel, which allows the controlled release of the cleaning fluid on sensitive surfaces. The chemical gel exhibits optimal viscoelasticity, which facilitates its removal after the application without leaving residues on the object. Nanoparticles of calcium hydroxide and lactate, dispersed in 2-propanol, were used to adjust the pH up to the natural value of leather, preventing too high alkalinity which causes swelling of fibers and denaturation of the collagen. The treated samples were characterized using scanning electron microscopy, controlled environment dynamic mechanical analysis, and infrared spectroscopy. The analytical assessment validated the use of tools derived from colloid and materials science for the preservation of collagen-based artifacts.

Solvent effects in the synergistic solvent extraction of Co2+

International Nuclear Information System (INIS)

Kandil, A.T.; Ramadan, A.

1979-01-01

The extraction of Co 2+ from a 0.1M ionic strength aqueous phase (Na + , CH 3 COOH) of pH = 5.1 was studied using thenoyltrifluoroacetone, HTTA, in eight different solvents and HTTA + trioctylphosphine oxide, TOPO, in the same solvents. A comparison of the effect of solvent dielectric constant on the equilibrium constant shows a synergism as a result of the increased hydrophobic character imparted to the metal complex due to the formation of the TOPO adduct. (author)

Green analytical chemistry - the use of surfactants as a replacement of organic solvents in spectroscopy

Science.gov (United States)

Pharr, Daniel Y.

2017-07-01

This chapter gives an introduction to the many practical uses of surfactants in analytical chemistry in replacing organic solvents to achieve greener chemistry. Taking a holistic approach, it covers some background of surfactants as chemical solvents, their properties and as green chemicals, including their environmental effects. The achievements of green analytical chemistry with micellar systems are reviewed in all the major areas of analytical chemistry where these reagents have been found to be useful.

SOLVENT FIRE BY-PRODUCTS

Energy Technology Data Exchange (ETDEWEB)

Walker, D; Samuel Fink, S

2006-05-22

Southwest Research Institute (SwRI) conducted a burn test of the Caustic-Side Solvent Extraction (CSSX) solvent to determine the combustion products. The testing showed hydrogen fluoride gas is not a combustion product from a solvent fire when up to 70% of the solvent is consumed. The absence of HF in the combustion gases may reflect concentration of the modifier containing the fluoride groups in the unburned portion. SwRI reported results for other gases (CO, HCN, NOx, formaldehyde, and hydrocarbons). The results, with other supporting information, can be used for evaluating the consequences of a facility fire involving the CSSX solvent inventory.

An overview of industrial solvent use or is there life after chlorinated solvents?

International Nuclear Information System (INIS)

Green, B.

1991-01-01

Everyone using industrial chemicals has been affected by the fire- storm of new regulations governing solvent use. How will companies currently using hazardous solvents prepare for the changes ahead? What will the impact be on commonly used industrial solvents? What effect are environmental pressures having on solvent use and disposal? Are the responsible individuals in your company up-to-date on phase-out schedules? This paper is written for an audience of compliance coordinators, consultants, production engineers and corporate management. In it, the either addresses the above questions and discusses the specific products affected. The author reviews currently available alternatives to chlorinated and hazardous solvents and introduces a simple system for rating alternatives. The program also includes a discussion of solvent minimization programs and worker reeducation

Wood fuel from early thinning and plantation cleaning. An international review

International Nuclear Information System (INIS)

Puttock, D.; Richardsson, J.

1998-01-01

Activities 1.2 (Forest management) and 1.2 (Harvesting) of Task XII/IEA Bioenergy Agreement carried out an international review of wood fuel from plantation cleaning and early thinning. The participating countries were Canada, Denmark, Finland, the Netherlands, New Zealand, Sweden and the United Kingdom. The individual country reviews and an international summary are presented in this paper. Each report gives country-related background information on forestry and wood utilization, energy potential from plantation cleaning and early thinning, environmental considerations from the viewpoint of wood fuel recovery, silvicultural systems and methods, cost of wood fuel, and knowledge gaps and problems

A Cultural Look at Moral Purity: Wiping the Face Clean

Directory of Open Access Journals (Sweden)

Spike W. S. eLee

2015-05-01

Full Text Available Morality is associated with bodily purity in the custom of many societies. Does that imply moral purity is a universal psychological phenomenon? Empirically, it has never been examined, as all prior experimental data came from Western samples. Theoretically, we suggest the answer is not so straightforward—it depends on the kind of universality under consideration. Combining perspectives from cultural psychology and embodiment, we predict a culture-specific form of moral purification. Specifically, given East Asians’ emphasis on the face as a representation of public self-image, we hypothesize that facial purification should have particularly potent moral effects in a face culture. Data show that face-cleaning (but not hands-cleaning reduces guilt and regret most effectively against a salient East Asian cultural background. It frees East Asians from guilt-driven prosocial behavior. In the wake of their immorality, they find a face-cleaning product especially appealing and spontaneously choose to wipe their face clean. These patterns highlight both culturally variable and universal aspects of moral purification. They further suggest an organizing principle that informs the vigorous debate between embodied and amodal perspectives.

Solvent - solute interaction

International Nuclear Information System (INIS)

Urbanczyk, A.; Kalinowski, M.K.

1983-01-01

The electronic absorption spectrum of vanadyl acetylacetonate has been studied in 15 organic solvents. It has been found that wavenumbers and molar absorptivities of the long-wavelength bands (d-d transitions) can be well described by a complementary Lewis acid-base model including Gutmann's donor number [Gutmann V., Wychera E., Inorg. Nucl. Chem. Letters 2, 257 (1966)] and acceptor number [Mayer U., Gutmann V., Gerger W., Monatsh. Chem. 106, 1235 (1975)] of a solvent. This model describes also the solvent effect of the hyperfine splitting constant, Asub(iso)( 51 V), from e.s.r. spectra of VOacac 2 . These observations are discussed in terms of the donor-acceptor concept for solvent-solute interactions. (Author)

Deasphalting solvents

International Nuclear Information System (INIS)

Carrillo, J. A; Caceres, J; Vela, G; Bueno, H

1996-01-01

This paper describes how the deasphalted oil (DMO) or demetalized oil (DMO) quality (CCR, Ni, V end asphaltenes contents) changes with: DAO or DMO yield, solvent/feed ratio, type of vacuum reside (from paraffinic to blends with vis breaking bottoms), extraction temperature and extraction solvent (propane, propylene, n-butane and I butane)

Clean data

CERN Document Server

Squire, Megan

2015-01-01

If you are a data scientist of any level, beginners included, and interested in cleaning up your data, this is the book for you! Experience with Python or PHP is assumed, but no previous knowledge of data cleaning is needed.

Evaluating impacts of Clean Air Act compliance strategies

International Nuclear Information System (INIS)

Shirer, D.A.; Evans, R.J.; Harrison, C.D.; Kehoe, D.B.

1993-01-01

The Clean Air Act Amendments of 1990 requires that by the year 2000, US SO 2 emissions must be reduced by 10 million tons. This requirement will have significant impact on coal-fired electric utilities. As a result, most utilities are currently evaluating numerous compliance options, including buying allowances, coal cleaning/blending/switching, and flue gas scrubbing. Moreover, each utility must address its own unique circumstances with regard to competition, efficiency, capital expenditures, reliability, etc. and many utilities may choose a combination of compliance options to simultaneously satisfy their environmental, performance, and financial objectives. The Coal Quality Expert, which is being developed under a clean coal technology project funded by US DOE and EPRI, will predict the economic, operational, and environmental benefits of using higher-quality coals and provides an assessment of the merits of various post-combustion control technologies for specific utility applications. This paper presents background on how utilities evaluate their compliance options, and it describes how the Coal Quality Expert could be used for such evaluations in the future to assure that each utility can select the best combination of coal specifications and emission control technologies to meet its compliance objectives

Parental Occupational Exposure to Organic Solvents and Testicular Germ Cell Tumors in their Offspring

DEFF Research Database (Denmark)

Le Cornet, Charlotte; Fervers, Béatrice; Pukkala, Eero

2017-01-01

BACKGROUND: Testicular germ cell tumors (TGCT) were suggested to have a prenatal environmentally related origin. The potential endocrine disrupting properties of certain solvents may interfere with the male genital development in utero. OBJECTIVES: We aimed to assess the association between......-Nordic Occupational Cancer Study Job-Exposure Matrix. Conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Overall, no association was found between prenatal maternal exposure to solvents and TGCT risk. In subset analyses using only mothers for whom...

Improvement of solvents for chemical decontamination: nickel ferrites removal

International Nuclear Information System (INIS)

Figueroa, Carlos A.; Morando, Pedro J.; Blesa, Miguel A.

1999-01-01

Carboxylic acids are usually included in commercial solvents for the chemical cleaning and decontamination of metal surfaces from the oxide layers grown and/or deposited from high temperature water by corrosive process. In particular oxalic acid is included in second path of AP-Citrox method. However, in some cases, their use shows low efficiency. This fact is attributed to the special passivity of the mixed oxides as nickel ferrites. This work reports a kinetic study of dissolution of a synthetic nickel ferrite (NiFe 2 O 4 ) confronted with simple oxides (NiO and Fe 2 O 3 ) in mineral acids and oxalic acid. The dissolution factor and reaction rate were determined in several conditions (reactive concentrations, pH and added ferrous ions). Experimental data of dissolution (with and without Fe(II) added) show a congruent kinetic regime. Pure nickel oxide (NiO) is rather resistant to the attack by oxalic acid solutions, and ferrous ions do not accelerate dissolution. In fact, nickel oxide dissolves better by oxidative attack that takes advantage of the higher lability of Ni 3+ . It may be concluded that oxalic acid operates to dissolve iron, and the ensuing disruption of the solid framework accelerates the release of nickel. Our results point to use more reactive solvents in iron from mixed oxides and to the possibility of using one stage decontamination method. (author)

High-resolution clean-sc

NARCIS (Netherlands)

Sijtsma, P.; Snellen, M.

2016-01-01

In this paper a high-resolution extension of CLEAN-SC is proposed: HR-CLEAN-SC. Where CLEAN-SC uses peak sources in “dirty maps” to define so-called source components, HR-CLEAN-SC takes advantage of the fact that source components can likewise be derived from points at some distance from the peak,

Controlling the clean room atmosphere

International Nuclear Information System (INIS)

Meeks, R.F.

1979-01-01

Several types of clean rooms are commonly in use. They include the conventional clean room, the horizontal laminar flow clean room, the vertical laminar flow clean room and a fourth type that incorporates ideas from the previous types and is known as a clean air bench or hood. These clean rooms are briefly described. The origin of contamination and methods for controlling the contamination are discussed

[Surface Cleaning and Disinfection in the Hospital. Improvement by Objective Monitoring and Intervention].

Science.gov (United States)

Woltering, R; Hoffmann, G; Isermann, J; Heudorf, U

2016-11-01

Background and Objective: An assessment of cleaning and disinfection in hospitals by the use of objective surveillance and review of mandatory corrective measures was undertaken. Methods: A prospective examination of the cleaning and disinfection of surfaces scheduled for daily cleaning in 5 general care hospitals by use of an ultraviolet fluorescence targeting method (UVM) was performed, followed by structured educational and procedural interventions. The survey was conducted in hospital wards, operating theatres and intensive care units. Cleaning performance was measured by complete removal of UVM. Training courses and reinforced self-monitoring were implemented after the first evaluation. 6 months later, we repeated the assessment for confirmation of success. Results: The average cleaning performance was 34% (31/90) at base-line with significant differences between the 5 hospitals (11-67%). The best results were achieved in intensive care units (61%) and operating theatres (58%), the worst results in hospital wards (22%). The intervention significantly improved cleaning performance up to an average of 69% (65/94; +34.7%; 95% confidence interval (CI): 21.2-48.3; pcleaning and disinfection of surfaces by fluorescence targeting is appropriate for evaluating hygiene regulations. An intervention can lead to a significant improvement of cleaning performance. As part of a strategy to improve infection control in hospitals, fluorescence targeting enables a simple inexpensive and effective surveillance of the cleaning performance and corrective measures. © Georg Thieme Verlag KG Stuttgart · New York.

Increased risk for hepatitis C associated with solvent use among Canadian Aboriginal injection drug users

Directory of Open Access Journals (Sweden)

Jolly Ann M

2010-07-01

Full Text Available Abstract Background Solvent abuse is a particularly serious issue affecting Aboriginal people. Here we examine the association between solvent use and socio-demographic variables, drug-related risk factors, and pathogen prevalence in Aboriginal injection drug users (IDU in Manitoba, Canada. Methods Data originated from a cross-sectional survey of IDU from December 2003 to September 2004. Associations between solvent use and variables of interest were assessed by multiple logistic regression. Results A total of 266 Aboriginal IDU were included in the analysis of which 44 self-reported recent solvent use. Hepatitis C infection was 81% in solvent-users, compared to 55% in those reporting no solvent use. In multivariable models, solvent-users were younger and more likely to be infected with hepatitis C (AOR: 3.5; 95%CI: 1.3,14.7, to have shared needles in the last six months (AOR: 2.6; 95%CI:1.0,6.8, and to have injected talwin & Ritalin (AOR: 10.0; 95%CI: 3.8,26.3. Interpretation High hepatitis C prevalence, even after controlling for risky injection practices, suggests that solvent users may form closed networks of higher risk even amongst an already high-risk IDU population. Understanding the social-epidemiological context of initiation and maintenance of solvent use is necessary to address the inherent inequalities encountered by this subpopulation of substance users, and may inform prevention strategies for other marginalized populations.

Porous fiber formation in polymer-solvent system undergoing solvent evaporation

Science.gov (United States)

Dayal, Pratyush; Kyu, Thein

2006-08-01

Temporal evolution of the fiber morphology during dry spinning has been investigated in the framework of Cahn-Hilliard equation [J. Chem. Phys. 28, 258 (1958)] pertaining to the concentration order parameter or volume fraction given by the Flory-Huggins free energy of mixing [P. J. Flory, Principles of Polymer Chemistry (Cornell University Press, Ithaca, NY, 1953), p. 672] in conjunction with the solvent evaporation rate. To guide the solvent evaporation induced phase separation, equilibrium phase diagram of the starting polymer solution was established on the basis of the Flory-Huggins free energy of mixing. The quasi-steady-state approximation has been adopted to account for the nonconserved nature of the concentration field caused by the solvent loss. The process of solvent evaporation across the fiber skin-air interface was treated in accordance with the classical Fick's law [R. B. Bird et al., Transport Phenomena (J. Wiley, New York, 1960), p. 780]. The simulated morphologies include gradient type, hollow fiber type, bicontinuous type, and host-guest type. The development of these diverse fiber morphologies is explicable in terms of the phase diagram of the polymer solution in a manner dependent on the competition between the phase separation dynamics and rate of solvent evaporation.

Essential roles of protein-solvent many-body correlation in solvent-entropy effect on protein folding and denaturation: Comparison between hard-sphere solvent and water

International Nuclear Information System (INIS)

Oshima, Hiraku; Kinoshita, Masahiro

2015-01-01

In earlier works, we showed that the entropic effect originating from the translational displacement of water molecules plays the pivotal role in protein folding and denaturation. The two different solvent models, hard-sphere solvent and model water, were employed in theoretical methods wherein the entropic effect was treated as an essential factor. However, there were similarities and differences in the results obtained from the two solvent models. In the present work, to unveil the physical origins of the similarities and differences, we simultaneously consider structural transition, cold denaturation, and pressure denaturation for the same protein by employing the two solvent models and considering three different thermodynamic states for each solvent model. The solvent-entropy change upon protein folding/unfolding is decomposed into the protein-solvent pair (PA) and many-body (MB) correlation components using the integral equation theories. Each component is further decomposed into the excluded-volume (EV) and solvent-accessible surface (SAS) terms by applying the morphometric approach. The four physically insightful constituents, (PA, EV), (PA, SAS), (MB, EV), and (MB, SAS), are thus obtained. Moreover, (MB, SAS) is discussed by dividing it into two factors. This all-inclusive investigation leads to the following results: (1) the protein-water many-body correlation always plays critical roles in a variety of folding/unfolding processes; (2) the hard-sphere solvent model fails when it does not correctly reproduce the protein-water many-body correlation; (3) the hard-sphere solvent model becomes problematic when the dependence of the many-body correlation on the solvent number density and temperature is essential: it is not quite suited to studies on cold and pressure denaturating of a protein; (4) when the temperature and solvent number density are limited to the ambient values, the hard-sphere solvent model is usually successful; and (5) even at the ambient

Notification: Background Investigation Services EPA’s Efforts to Incorporate Environmental Justice Into Clean Air Act Inspections for Air Toxics

Science.gov (United States)

Project #OPE-FY14-0017, March 7, 2014. The OIG plans to begin the preliminary research phase of an evaluation of the EPA's efforts to incorporate environmental justice into Clean Air Act (CAA) inspections for air toxics.

Clean coal technologies

International Nuclear Information System (INIS)

Aslanyan, G.S.

1993-01-01

According to the World Energy Council (WEC), at the beginning of the next century three main energy sources - coal, nuclear power and oil will have equal share in the world's total energy supply. This forecast is also valid for the USSR which possesses more than 40% of the world's coal resources and continuously increases its coal production (more than 700 million tons of coal are processed annually in the USSR). The stringent environmental regulations, coupled with the tendency to increase the use of coal are the reasons for developing different concepts for clean coal utilization. In this paper, the potential efficiency and environmental performance of different clean coal production cycles are considered, including technologies for coal clean-up at the pre-combustion stage, advanced clean combustion methods and flue gas cleaning systems. Integrated systems, such as combined gas-steam cycle and the pressurized fluidized bed boiler combined cycle, are also discussed. The Soviet National R and D program is studying new methods for coal utilization with high environmental performance. In this context, some basic research activities in the field of clean coal technology in the USSR are considered. Development of an efficient vortex combustor, a pressurized fluidized bed gasifier, advanced gas cleaning methods based on E-beam irradiation and plasma discharge, as well as new catalytic system, are are presented. In addition, implementation of technological innovations for retrofitting and re powering of existing power plants is discussed. (author)

Selective solvent extraction of oils

Energy Technology Data Exchange (ETDEWEB)

1938-04-09

In the selective solvent extraction of naphthenic base oils, the solvent used consists of the extract obtained by treating a paraffinic base oil with a selective solvent. The extract, or partially spent solvent is less selective than the solvent itself. Selective solvents specified for the extraction of the paraffinic base oil are phenol, sulphur dioxide, cresylic acid, nitrobenzene, B:B/sup 1/-dichlorethyl ether, furfural, nitroaniline and benzaldehyde. Oils treated are Coastal lubricating oils, or naphthenic oils from the cracking, or destructive hydrogenation of coal, tar, lignite, peat, shale, bitumen, or petroleum. The extraction may be effected by a batch or counter-current method, and in the presence of (1) liquefied propane, or butane, or naphtha, or (2) agents which modify the solvent power such as, water, ammonia, acetonitrile, glycerine, glycol, caustic soda or potash. Treatment (2) may form a post-treatment effected on the extract phase. In counter-current treatment in a tower some pure selective solvent may be introduced near the raffinate outlet to wash out any extract therefrom.

Relation of average and highest solvent vapor concentrations in workplaces in small to medium enterprises and large enterprises.

Science.gov (United States)

Ukai, Hirohiko; Ohashi, Fumiko; Samoto, Hajime; Fukui, Yoshinari; Okamoto, Satoru; Moriguchi, Jiro; Ezaki, Takafumi; Takada, Shiro; Ikeda, Masayuki

2006-04-01

The present study was initiated to examine the relationship between the workplace concentrations and the estimated highest concentrations in solvent workplaces (SWPs), with special references to enterprise size and types of solvent work. Results of survey conducted in 1010 SWPs in 156 enterprises were taken as a database. Workplace air was sampled at > or = 5 crosses in each SWP following a grid sampling strategy. An additional air was grab-sampled at the site where the worker's exposure was estimated to be highest (estimated highest concentration or EHC). The samples were analyzed for 47 solvents designated by regulation, and solvent concentrations in each sample were summed up by use of additiveness formula. From the workplace concentrations at > or = 5 points, geometric mean and geometric standard deviations were calculated as the representative workplace concentration (RWC) and the indicator of variation in workplace concentration (VWC). Comparison between RWC and EHC in the total of 1010 SWPs showed that EHC was 1.2 (in large enterprises with>300 employees) to 1.7 times [in small to medium (SM) enterprises with enterprises and large enterprises, both RWC and EHC were significantly higher in SM enterprises than in large enterprises. Further comparison by types of solvent work showed that the difference was more marked in printing, surface coating and degreasing/cleaning/wiping SWPs, whereas it was less remarkable in painting SWPs and essentially nil in testing/research laboratories. In conclusion, the present observation as discussed in reference to previous publications suggests that RWC, EHC and the ratio of EHC/WRC varies substantially among different types of solvent work as well as enterprise size, and are typically higher in printing SWPs in SM enterprises.

Clean-up and matrix effect in LC-MS/MS analysis of food of plant origin for high polar herbicides.

Science.gov (United States)

Kaczyński, Piotr

2017-09-01

This study reports an innovative and sensitive procedure for analysis of difficult high polar herbicides (HPH) in diverse foods of plant origin. The QuPPe (Quick Polar Pesticides) method followed by determination by LC-MS/MS was modified. Chromatographic conditions, extraction, clean-up, and matrix effect were studied. Several liquid chromatography stationary and mobile phases were evaluated, and it was found that hydrophilic interaction chromatography (HILIC) gives good retention and sensitivity. An acidified methanol-water mixture was used as an effective extraction solvent of eleven HPH. Dispersive solid-phase clean-up sorbents (C18, GCB, Florisil, chitosan and graphene) were evaluated. The efficiency of the method was examined using data on recovery, precision and matrix effects. High extraction yields were achieved, and recoveries were within the 64-97% range with relative standard deviations <20% for all HPH in all commodities. Low matrix effects were observed when graphene was used during clean-up of onion extract and when chitosan was used for wheat, potato and pea extract. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biodegradation of Chlorinated Solvents: Reactions near DNAPL and Enzyme Function

Energy Technology Data Exchange (ETDEWEB)

McCarty, P. L.; Spormann, Alfred M.; Criddle, Craig, S.

2003-12-11

three to five times, leading to a more rapid clean-up of the DNAPL zone. The most favored electron donor to add is one which partitions well with the chlorinated solvent or can be concentrated near it. Unfortunately, an ideal electron donor, such as vegetable oil, is difficult to introduce and mix with DNAPL in the ground, doing this properly remains an engineering challenge. Numerical model studies have indicated that several factors may significantly influence the rate and extent of enhancement, including the inhibitory effects of PCE and cDCE, the level of ED concentration, DNAPL configuration, and competition for ED. Such factors need to be considered when contemplating engineered DNAPL bioremediation. Pseudomonas stuzeri KC is an organism that transforms CT to carbon dioxide and chloride without the formation of the hazardous intermediate, chloroform. This is accomplished by production and secretion of a molecule called PDTC. This study was direct ed towards determining how PDTC works. Cu (II) at a ratio of 1:1 Cu to PDTC was found to result in the most rapid CT transformation, confirming that the PDTC-Cu complex is both a reactant and a catalyst in CT transformation. CT degradation requires that the PDTC be in a reduced form, which is generated by contact with cell components. Fe(II) inhibits CT transformation by PDTC. Studies indicated that this inhibition is enhanced by some compound or factor in the supernatant with molecular weight greater than 10,000 Da. We have made progress in determining what this factor might be, but have not yet been able to identify it. In related studies, we found that CT transformation by another organism, Shewanella oneidensis MR1, also involves an excreted factor, but this factor is different from PDTC and results in chloroform transformation as an intermediate. Our studies have indicated that this factor is similar to vitamin K2, and we have also confirmed that vitamin K2 does transform C T into chloroform.

Biodegradation of Chlorinated Solvents: Reactions near DNAPL and Enzyme Function

International Nuclear Information System (INIS)

McCarty, P. L.; Spormann, Alfred M.; Criddle, Craig S.

2003-01-01

three to five times, leading to a more rapid clean-up of the DNAPL zone. The most favored electron donor to add is one which partitions well with the chlorinated solvent or can be concentrated near it. Unfortunately, an ideal electron donor, such as vegetable oil, is difficult to introduce and mix with DNAPL in the ground, doing this properly remains an engineering challenge. Numerical model studies have indicated that several factors may significantly influence the rate and extent of enhancement, including the inhibitory effects of PCE and cDCE, the level of ED concentration, DNAPL configuration, and competition for ED. Such factors need to be considered when contemplating engineered DNAPL bioremediation. Pseudomonas stuzeri KC is an organism that transforms CT to carbon dioxide and chloride without the formation of the hazardous intermediate, chloroform. This is accomplished by production and secretion of a molecule called PDTC. This study was direct ed towards determining how PDTC works. Cu (II) at a ratio of 1:1 Cu to PDTC was found to result in the most rapid CT transformation, confirming that the PDTC-Cu complex is both a reactant and a catalyst in CT transformation. CT degradation requires that the PDTC be in a reduced form, which is generated by contact with cell components. Fe(II) inhibits CT transformation by PDTC. Studies indicated that this inhibition is enhanced by some compound or factor in the supernatant with molecular weight greater than 10,000 Da. We have made progress in determining what this factor might be, but have not yet been able to identify it. In related studies, we found that CT transformation by another organism, Shewanella oneidensis MR1, also involves an excreted factor, but this factor is different from PDTC and results in chloroform transformation as an intermediate. Our studies have indicated that this factor is similar to vitamin K2, and we have also confirmed that vitamin K2 does transform C T into chloroform

Purex process solvent: literature review

International Nuclear Information System (INIS)

Geier, R.G.

1979-10-01

This document summarizes the data on Purex process solvent presently published in a variety of sources. Extracts from these various sources are presented herein and contain the work done, the salient results obtained, and the original, unaltered conclusions of the author of each paper. Three major areas are addressed: solvent stability, solvent quality testing, and solvent treatment processes. 34 references, 44 tables

Purex process solvent: literature review

Energy Technology Data Exchange (ETDEWEB)

Geier, R.G.

1979-10-01

This document summarizes the data on Purex process solvent presently published in a variety of sources. Extracts from these various sources are presented herein and contain the work done, the salient results obtained, and the original, unaltered conclusions of the author of each paper. Three major areas are addressed: solvent stability, solvent quality testing, and solvent treatment processes. 34 references, 44 tables.

Wavelet imaging cleaning method for atmospheric Cherenkov telescopes

Science.gov (United States)

Lessard, R. W.; Cayón, L.; Sembroski, G. H.; Gaidos, J. A.

2002-07-01

We present a new method of image cleaning for imaging atmospheric Cherenkov telescopes. The method is based on the utilization of wavelets to identify noise pixels in images of gamma-ray and hadronic induced air showers. This method selects more signal pixels with Cherenkov photons than traditional image processing techniques. In addition, the method is equally efficient at rejecting pixels with noise alone. The inclusion of more signal pixels in an image of an air shower allows for a more accurate reconstruction, especially at lower gamma-ray energies that produce low levels of light. We present the results of Monte Carlo simulations of gamma-ray and hadronic air showers which show improved angular resolution using this cleaning procedure. Data from the Whipple Observatory's 10-m telescope are utilized to show the efficacy of the method for extracting a gamma-ray signal from the background of hadronic generated images.

Fiscal 1999 achievement report on regional consortium research and development project. Regional consortium on energy research in its 3rd year (Development of an environmentally-friendly industrial cleaning system using supercritical CO2 fluid); 1999 nendo chorinkai ryutai wo mochiita kankyo chowagata kogyo senjo sochi no kaihatsu seika hokokusho. 3

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

In high-technology industries such as the semiconductor industry, cleaning operations are indispensable. In these industries, replacement of the current method with a new one has become an urgent matter, thanks to the new control imposed on pollutant CFC (chlorofluorocarbon). Using a supercritical fluid, whose density and other features may be regulated extensively and continuously by controlling temperature and pressure, various conditions may be set in detail for the cleaning element, such as the dissolving power, dispersion force, surface activity, and chemical reactivity. The fluid is environmentally friendly and free of pollution. Facilities for recovering, regenerating, and circulating the solvent are incorporated into a test cleaner built in the preceding fiscal year, and a new system is completed. The system is operated in a test run for performance assessment, and data are collected to specify cleaning conditions best for each kind of the target items. Studies are made to expand the scope of system application for use under supercritical conditions. An experiment is conducted using a pollutant model, and a method to analyze the degree of cleaning is studied using an effective diffusion coefficient. A self-cleaning method is studied for the filter for the regeneration of the supercritical cleaning solvent. A market research is carried out for the commercialization of the industrial cleaning system. (NEDO)

WINDOW-CLEANING

CERN Multimedia

Environmental Section / ST-TFM

2001-01-01

The two-month window-cleaning session on the Meyrin, Prévessin and LEP sites will soon begin. The cleaning contractors will work from Monday to Saturday, every week from 4.00 a.m. to 8.00 p.m. The work will be organised so as to disturb users as little as possible. In any event, a work notice will be left in each office 24 hours beforehand. To prevent any damage to documents or items which could occur despite the precautions taken, please clear completely the window-sills and the area immediately around them. If, however, for valid reasons, the work cannot be done on the scheduled day, please inform the Environmental Section by telephoning: 73753 / 74233 / 72242 If you are going to be absent during this two-month period, we should be grateful if you would clear the above mentioned areas before your departure. REMINDER To allow more thorough cleaning of the entrance doors to buildings and also facilitate the weekly work of the cleaning contractors, we ask you to make use of the notice boards at the...

Solvent/non-solvent sintering: a novel route to create porous microsphere scaffolds for tissue regeneration.

Science.gov (United States)

Brown, Justin L; Nair, Lakshmi S; Laurencin, Cato T

2008-08-01

Solvent/non-solvent sintering creates porous polymeric microsphere scaffolds suitable for tissue engineering purposes with control over the resulting porosity, average pore diameter, and mechanical properties. Five different biodegradable biocompatible polyphosphazenes exhibiting glass transition temperatures from -8 to 41 degrees C and poly (lactide-co-glycolide), (PLAGA) a degradable polymer used in a number of biomedical settings, were examined to study the versatility of the process and benchmark the process to heat sintering. Parameters such as: solvent/non-solvent sintering solution composition and submersion time effect the sintering process. PLAGA microsphere scaffolds fabricated with solvent/non-solvent sintering exhibited an interconnected porosity and pore size of 31.9% and 179.1 mum, respectively which was analogous to that of conventional heat sintered PLAGA microsphere scaffolds. Biodegradable polyphosphazene microsphere scaffolds exhibited a maximum interconnected porosity of 37.6% and a maximum compressive modulus of 94.3 MPa. Solvent/non-solvent sintering is an effective strategy for sintering polymeric microspheres, with a broad spectrum of glass transition temperatures, under ambient conditions making it an excellent fabrication route for developing tissue engineering scaffolds and drug delivery vehicles. (c) 2007 Wiley Periodicals, Inc.

Measurement and correlation of solubility of cefmenoxime hydrochloride in pure solvents and binary solvent mixtures

International Nuclear Information System (INIS)

Wang, Jinxiu; Xie, Chuang; Yin, Qiuxiang; Tao, Linggang; Lv, Jun; Wang, Yongli; He, Fang; Hao, Hongxun

2016-01-01

Highlights: • Solubility of cefmenoxime hydrochloride in pure and binary solvents was determined. • The experimental solubility data were correlated by thermodynamic models. • A model was employed to calculate the melting temperature of cefmenoxime hydrochloride. • Mixing thermodynamic properties of cefmenoxime hydrochloride were calculated. - Abstract: The solubility of cefmenoxime hydrochloride in pure solvents and binary solvent mixtures was measured at temperatures from (283.15 to 313.15) K by using the UV spectroscopic method. The results reveal that the solubility of cefmenoxime hydrochloride increases with increasing temperature in all solvent selected. The solubility of cefmenoxime hydrochloride reaches its maximum value when the mole fraction of isopropanol is 0.2 in the binary solvent mixtures of (isopropanol + water). The modified Apelblat equation and the NRTL model were successfully used to correlate the experimental solubility in pure solvents while the modified Apelblat equation, the CNIBS/R–K model and the Jouyban–Acree model were applied to correlate the solubility in binary solvent mixtures. In addition, the mixing thermodynamic properties of cefmenoxime hydrochloride in different solvents were also calculated based on the NRTL model and experimental solubility data.

Measurement and prediction of dabigatran etexilate mesylate Form II solubility in mono-solvents and mixed solvents

International Nuclear Information System (INIS)

Xiao, Yan; Wang, Jingkang; Wang, Ting; Ouyang, Jinbo; Huang, Xin; Hao, Hongxun; Bao, Ying; Fang, Wen; Yin, Qiuxiang

2016-01-01

Highlights: • Solubility of DEM Form II in mono-solvents and binary solvent mixtures was measured. • Regressed UNIFAC model was used to predict the solubility in solvent mixtures. • The experimental solubility data were correlated by different models. - Abstract: UV spectrometer method was used to measure the solubility data of dabigatran etexilate mesylate (DEM) Form II in five mono-solvents (methanol, ethanol, ethane-1,2-diol, DMF, DMAC) and binary solvent mixtures of methanol and ethanol in the temperature range from 287.37 K to 323.39 K. The experimental solubility data in mono-solvents were correlated with modified Apelblat equation, van’t Hoff equation and λh equation. GSM model and Modified Jouyban-Acree model were employed to correlate the solubility data in mixed solvent systems. And Regressed UNIFAC model was used to predict the solubility of DEM Form II in the binary solvent mixtures. Results showed that the predicted data were consistent with the experimental data.

Association between Residential Proximity to PERC Dry Cleaning Establishments and Kidney Cancer in New York City

Directory of Open Access Journals (Sweden)

Jing Ma

2009-01-01

Full Text Available Perchloroethylene (PERC is commonly used as a dry cleaning solvent and is believed to be a human carcinogen, with occupational exposure resulting in elevated rates of kidney cancer. Living near a dry cleaning facility using PERC has been demonstrated to increase the risk of PERC exposure throughout the building where the dry cleaning is conducted, and in nearby buildings. We designed this study to test the hypothesis that living in an area where there are many PERC dry cleaners increases PERC exposure and the risk of kidney cancer. We matched the diagnosis of kidney cancer from hospitalization discharge data in New York City for the years 1994–2004 by zip code of patient residence to the zip code density of dry cleaners using PERC, as a surrogate for residential exposure. We controlled for age, race, gender, and median household income. We found a significant association between the density of PERC dry cleaning establishments and the rate of hospital discharges that include a diagnosis of kidney cancer among persons 45 years of age and older living in New York City. The rate ratio increased by 10 to 27% for the populations in zip codes with higher density of PERC dry cleaners. Because our exposure assessment is inexact, we are likely underestimating the real association between exposure to PERC and rates of kidney cancer. Our results support the hypothesis that living near a dry cleaning facility using PERC increases the risk of PERC exposure and of developing kidney cancer. To our knowledge, this study is the first to demonstrate an association between residential PERC exposure and cancer risk.

Association between Residential Proximity to PERC Dry Cleaning Establishments and Kidney Cancer in New York City

International Nuclear Information System (INIS)

Ma, J.; Lessner, L.; Lessner, L.; Carpenter, D.O.; Schreiber, J.

2010-01-01

Perchloroethylene (PERC) is commonly used as a dry cleaning solvent and is believed to be a human carcinogen, with occupational exposure resulting in elevated rates of kidney cancer. Living near a dry cleaning facility using PERC has been demonstrated to increase the risk of PERC exposure throughout the building where the dry cleaning is conducted, and in nearby buildings. We designed this study to test the hypothesis that living in an area where there are many PERC dry cleaners increases PERC exposure and the risk of kidney cancer. We matched the diagnosis of kidney cancer from hospitalization discharge data in New York City for the years 1994-2004 by zip code of patient residence to the zip code density of dry cleaners using PERC, as a surrogate for residential exposure. We controlled for age, race, gender, and median household income. We found a significant association between the density of PERC dry cleaning establishments and the rate of hospital discharges that include a diagnosis of kidney cancer among persons 45 years of age and older living in New York City. The rate ratio increased by 10 to 27% for the populations in zip codes with higher density of PERC dry cleaners. Because our exposure assessment is inexact, we are likely underestimating the real association between exposure to PERC and rates of kidney cancer. Our results support the hypothesis that living near a dry cleaning facility using PERC increases the risk of PERC exposure and of developing kidney cancer. To our knowledge, this study is the first to demonstrate an association between residential PERC exposure and cancer risk.

Bioremediation of soil and groundwater contaminated with stoddard solvent and mop oil using the PetroClean bioremediation system

International Nuclear Information System (INIS)

Schmitt, E.K.; Lieberman, M.T.; Caplan, J.A.; Blaes, D.; Keating, P.; Richards, W.

1991-01-01

This paper reports that Environmental Science and Engineering Inc. (ESE) was contracted by a confidential industrial client to perform a three-phased project. Phase I involved characterizing the site and delineating the extent of subsurface contamination. Phase II included biofeasibility and pilot-scale evaluations, determining remedial requirements, and designing the full-scale treatment system. Phase III involved implementing and operating the designed in situ bioremediation system (i.e., PetroClean 4000) to achieve site closure

Reactor water clean-up device

International Nuclear Information System (INIS)

Tanaka, Koji; Egashira, Yasuo; Shimada, Fumie; Igarashi, Noboru.

1983-01-01

Purpose: To save a low temperature reactor water clean-up system indispensable so far and significantly simplify the system by carrying out the reactor water clean-up solely in a high temperature reactor water clean-up system. Constitution: The reactor water clean-up device comprises a high temperature clean-up pump and a high temperature adsorption device for inorganic adsorbents. The high temperature adsorption device is filled with amphoteric ion adsorbing inorganic adsorbents, or amphoteric ion adsorbing inorganic adsorbents and anionic adsorbing inorganic adsorbents. The reactor water clean-up device introduces reactor water by the high temperature clean-up pump through a recycling system to the high temperature adsorption device for inorganic adsorbents. Since cations such as cobalt ions and anions such as chlorine ions in the reactor water are simultaneously removed in the device, a low temperature reactor water clean-up system which has been indispensable so far can be saved to realize the significant simplification for the entire system. (Seki, T.)

Influence of the type of solvent on the development of superhydrophobicity from silane-based solution containing nanoparticles

Science.gov (United States)

Pantoja, M.; Abenojar, J.; Martinez, M. A.

2017-03-01

Superhydrophobic surfaces are very appealing for numerous industrial applications due to their self-cleaning capacity. Although there are different methods to manufacture superhydrophobic surfaces, some of them do not keep the aesthetic appearance of the neat surface. Sol-gel processes are a valid alternative when transparent coatings are desired. The main goal of this research is to study the viability of this method by making superhydrophobic coatings from silane-based solution containing SiO2 nanoparticles. The effect of using different solvents is investigated, as well as the role played by the different components of the solution (silane, nanoparticles and solvent). Solutions of methyltrimethoxisilane (MTS) and tetraethoxysilane (TEOS) and 1% of SiO2 (%wt) were prepared with different solvents (ethanol, ethanol/water and white spirit). The hydrophobicity of the developed coatings is studied using contact angle measurements, while the aesthetic appearance is evaluated with gloss and color measurements. Also, infrared spectroscopy, dynamic light scattering (DSL), and surface tension measurements are used to study the silane solutions. The results show that the capacity of solvents to promote the dispersion of the nanoparticles is crucial to ensuring superhydrophobicity, since these agglomerates provide the micro- and nano- surface roughness required to get a hierarchical structure. However, the combined use of silanes and nanoparticles is key to make a superhydrophobic surface because physical (the surface roughness provided by nanoparticles) and chemical characteristics (hydrophobicity provided by silanes) are coupled.

Microbial water quality in clean water tanks following inspection and cleaning

DEFF Research Database (Denmark)

Christensen, Sarah Christine Boesgaard; Esbjørn, Anne; Mollerup, Finn

Increased bacterial counts are often registered in drinking water leaving clean water tanks after the tanks have been emptied, inspected and cleaned by flushing. To investigate the reason for the increased bacterial concentrations and consequently limit it, samples from two clean water tanks befo...... start-up of the tanks, which may indicate that a substantial part of the bacteria in the drinking water leaving the tanks originated from the sand filter. This was supported by 16S DNA analyses....

Changes in background aerosol composition in Finland during polluted and clean periods studied by TEM/EDX individual particle analysis

Directory of Open Access Journals (Sweden)

J. V. Niemi

2006-01-01

Full Text Available Aerosol samples were collected at a rural background site in southern Finland in May 2004 during pollution episode (PM1~16 µg m−3, backward air mass trajectories from south-east, intermediate period (PM1~5 µg m−3, backtrajectories from north-east and clean period (PM1~2 µg m−3, backtrajectories from north-west/north. The elemental composition, morphology and mixing state of individual aerosol particles in three size fractions were studied using transmission electron microscopy (TEM coupled with energy dispersive X-ray (EDX microanalyses. The TEM/EDX results were complemented with the size-segregated bulk chemical measurements of selected ions and organic and elemental carbon. Many of the particles in PM0.2–1 and PM1–3.3 size fractions were strongly internally mixed with S, C and/or N. The major particle types in PM0.2–1 samples were 1 soot and 2 (ammoniumsulphates and their mixtures with variable amounts of C, K, soot and/or other inclusions. Number proportions of those two particle groups in PM0.2–1 samples were 0–12% and 83–97%, respectively. During the pollution episode, the proportion of Ca-rich particles was very high (26–48% in the PM1–3.3 and PM3.3–11 samples, while the PM0.2–1 and PM1–3.3 samples contained elevated proportions of silicates (22–33%, metal oxides/hydroxides (1–9% and tar balls (1–4%. These aerosols originated mainly from polluted areas of Eastern Europe, and some open biomass burning smoke was also brought by long-range transport. During the clean period, when air masses arrived from the Arctic Ocean, PM1–3.3 samples contained mainly sea salt particles (67–89% with a variable rate of Cl substitution (mainly by NO3−. During the intermediate period, the PM1–3.3 sample contained porous (sponge-like Na-rich particles (35% with abundant S, K and O. They might originate from the burning of wood pulp wastes of paper industry. The proportion of biological particles and C-rich fragments

Comparison of glow discharge cleaning with Taylor-type discharge cleaning on JFT-2

International Nuclear Information System (INIS)

Yokokura, Kenji; Matsuzaki, Yoshimi; Tani, Takashi

1983-01-01

Method of glow discharge cleaning (GDC) was applied to JFT-2 tokamak and the cleaning effect of GDC was compared with that of taylor-type discharge cleaning (TDC) on the same machin. Results show clearly their individual characteristics to remove light impurities. Their abilities of surface cleaning were compared each other by observing cleanliness of sample surfaces with a AES and by measuring decay times of produced gas pressures during discharge cleanings with a mass-analyser. It was shown that TDC method is better by several times than GDC method from a mass-analyser measurement. Moreover discharge cleaning time necessary to reduce light impurities in the normal plasma to a certain level was compared by monitoring time evolution of radiation loss power with a bolometer, and the time by TDC was only one fifth of that by GDC. The advantage of TDC may come from the excellently high hydrogen flux which interacts with the limiter and the wall. (author)

Cesium Concentration in MCU Solvent

International Nuclear Information System (INIS)

Walker, D

2006-01-01

During Modular Caustic-Side Solvent Extraction (CSSX) Unit (MCU) operations, Cs-137 concentrations in product streams will vary depending on the location in the process and on the recent process conditions. Calculations of cesium concentrations under a variety of operating conditions reveal the following: (1) Under nominal operations with salt solution feed containing 1.1 Ci Cs-137 per gallon, the maximum Cs-137 concentration in the process will occur in the strip effluent (SE) and equal 15-16.5 Ci/gal. (2) Under these conditions, the majority of the solvent will contain 0.005 to 0.01 Ci/gal, with a limited portion of the solvent in the contactor stages containing ∼4 Ci/gal. (3) When operating conditions yield product near 0.1 Ci Cs-137/gal in the decontaminated salt solution (DSS), the SE cesium concentration will be the same or lower than in nominal operations, but majority of the stripped solvent will increase to ∼2-3 Ci/gal. (4) Deviations in strip and waste stream flow rates cause the largest variations in cesium content: (a) If strip flow rates deviate by -30% of nominal, the SE will contain ∼23 Ci/gal, although the cesium content of the solvent will increase to only 0.03 Ci/gal; (b) If strip flow rate deviates by -77% (i.e., 23% of nominal), the SE will contain 54 Ci/gal and solvent will contain 1.65 Ci/gal. At this point, the product DSS will just reach the limit of 0.1 Ci/gal, causing the DSS gamma monitors to alarm; and (c) Moderate (+10 to +30%) deviations in waste flow rate cause approximately proportional increases in the SE and solvent cesium concentrations. Recovery from a process failure due to poor cesium stripping can achieve any low cesium concentration required. Passing the solvent back through the contactors while recycling DSS product will produce a ∼70% reduction during one pass through the contactors (assuming the stripping D value is no worse than 0.36). If the solvent is returned to the solvent hold tank (containing additional

The Development of an Automated Clean-up for Fat Extracts in the Routine Analysis of Organochlorine Compounds in Fish Meat

Directory of Open Access Journals (Sweden)

Ana Andreea CIOCA

2017-05-01

Full Text Available The present work describes the development of a new, automatic High Performance Liquid Chromatography (HPLC Clean-up step, in the methodology of sample preparation and multi-residue determination of organochlorine compounds (OCs in fish meat. 24 OCs were taken into study. In addition 7 Polychlorinated Biphenyls (PCBs, 7 chlorobenzene compounds and one 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD were investigated. The HPLC conditions were established in accordance with the validated traditional Clean-up step of the laboratory. The technique was applied on a dilution of analytes of interest in order to establish the period of time in which the compounds are eluted. Another set of experiments involved fish oil, in order to identify and separate the fat fraction from the analytes. To confirm the findings of the experiments mentioned above, extracts of fish samples obtained after Accelerated Solvent Extraction (ASE were examined. The samples were spiked with the analytes of interest before HPLC clean-up step and quantified through Gas Chromatography coupled with tandem Mass Spectrometry (GC-MS/MS. A HPLC clean-up technique lasting 38 minutes/sample was developed. The method is not suitable for OCs such as Endosulfansulfat and Endrine Ketone due to the very low recovery results.Â

Iodine removing method in organic solvent

International Nuclear Information System (INIS)

Suzuki, Takeo; Sakurai, Manabu

1988-01-01

Purpose: To effectively remove iodine in an organic solvent to thereby remove iodine in the solvent that can be re-used or put to purning treatment. Method: Organic solvent formed from wastes of nuclear facilities is mixed with basic lead acetate, or silica gel or activated carbon incorporated with such a compound to adsorb iodine in the organic solvent to the basic lead acetate. Then, iodine in the organic solvent is removed by separating to eliminate the basic lead acetate adsorbing iodine from the organic solvent or by passing the organic solvent through a tower or column charged or pre-coated with silica gel or activated carbon incorporated with lead acetate. By using basic lead acetate as the adsorbents, iodine can effective by adsorbed and eliminated. Thus, the possibility of circumstantial release of iodine can be reduced upon reusing or burning treatment of the organic solvent. (Kamimura, M.)

Sensibilidade do carrapato Boophilus microplus a solventes Sensibility of Boophilus microplus tick to solvents

Directory of Open Access Journals (Sweden)

Ana Carolina de Souza Chagas

2003-02-01

Full Text Available Os experimentos envolvendo o uso de acaricidas sintéticos ou naturais, geralmente necessitam da utilização de um solvente. Com a finalidade de verificar a sensibilidade do carrapato bovino Boophilus microplus a diferentes solventes, larvas e fêmeas ingurgitadas deste ectoparasito foram expostas a sete solventes em cinco diferentes concentrações, na ausência e presença de azeite de oliva. Os resultados mostraram que a utilização do azeite de oliva não produz resultados diferentes estatisticamente em testes de larvas com papel impregnado, fato não verificado em testes de imersão de adultos com compostos hidrofílicos. A mortalidade média causada pelos solventes foi menor nos testes com papel impregnado, aumentando nos testes de imersão de larvas e de adultos. Solventes de baixo peso molecular e pouca viscosidade como o álcool metílico e o álcool etílico, não interferiram na mortalidade média em testes biológicos de B. microplus, principalmente em concentrações inferiores a 76%.Experiments carried out with synthetic or natural acaricides usually use a solvent. To investigate the sensitivity of Boophilus microplus cattle tick to different solvents, larvae and engorged female were subjected to seven solvents in five different concentrations. It was done in the presence and absence of olive oil. The results showed that the utilization of olive oil doesn't produce different statistical results in impregnated paper larvae test. It did not happen in adults immersion test with hydrophilic compounds. The mean mortality caused by solvents was small in impregnated paper larvae test, increasing in immersion tests of larvae and adults. Solvents with low molecular weight and viscosity like ethyl alcohol and methyl alcohol did not cause interference in the mortality of B. microplus in biological tests, mainly in concentrations below 76%.

Noise-Induced Hearing Loss in Korean Workers: Co-Exposure to Organic Solvents and Heavy Metals in Nationwide Industries

Science.gov (United States)

Choi, Yoon-Hyeong; Kim, KyooSang

2014-01-01

Background Noise exposure is a well-known contributor to work-related hearing loss. Recent biological evidence suggests that exposure to ototoxic chemicals such as organic solvents and heavy metals may be additional contributors to hearing loss. However, in industrial settings, it is difficult to determine the risks of hearing loss due to these chemicals in workplaces accompanied by excessive noise exposure. A few studies suggest that the effect of noise may be enhanced by ototoxic chemicals. Therefore, this study investigated whether co-exposure to organic solvents and/or heavy metals in the workplace modifies the risk of noise exposure on hearing loss in a background of excessive noise. Methods We examined 30,072 workers nationwide in a wide range of industries from the Korea National Occupational Health Surveillance 2009. Data on industry-based exposure (e.g., occupational noise, heavy metals, and organic solvents) and subject-specific health outcomes (e.g., audiometric examination) were collected. Noise was measured as the daily 8-h time-weighted average level. Air conduction hearing thresholds were measured from 0.5 to 6 kHz, and pure-tone averages (PTA) (i.e., means of 2, 3, and 4 kHz) were computed. Results In the multivariate linear model, PTA increment with occupational noise were 1.64-fold and 2.15-fold higher in individuals exposed to heavy metals and organic solvents than in unexposed individuals, respectively. Conclusion This study provides nationwide evidence that co-exposure to heavy metals and/or organic solvents may exacerbate the effect of noise exposure on hearing loss in workplaces. These findings suggest that workers in industries dealing with heavy metals or organic solvents are susceptible to such risks. PMID:24870407

Limonene and tetrahydrofurfuryl alcohol cleaning agent

Science.gov (United States)

Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

1996-05-07

The present invention is a tetrahydrofurfuryl alcohol and limonene or terpineol cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

Limonene and tetrahydrofurfurly alcohol cleaning agent

Science.gov (United States)

Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

1997-10-21

The present invention is a tetrahydrofurfuryl alcohol and limonene cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

Clean Hands Count

Medline Plus

Full Text Available ... has been rented. This feature is not available right now. Please try again later. Published on May ... 34 How The Clean Hands - Safe Hands System Works - Duration: 3:38. Clean Hands-Safe Hands 5, ...

Next Generation Solvent Development for Caustic-Side Solvent Extraction of Cesium

Energy Technology Data Exchange (ETDEWEB)

Moyer, Bruce A. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Birdwell, Joseph F. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Bonnesen, Peter V. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

2014-03-01

This report summarizes the FY 2010 and 2011 accomplishments at Oak Ridge National Laboratory (ORNL) in developing the Next Generation Caustic-Side Solvent Extraction (NG-CSSX) process, referred to commonly as the Next Generation Solvent (NGS), under funding from the U.S. Department of Energy, Office of Environmental Management (DOE-EM), Office of Technology Innovation and Development. The primary product of this effort is a process solvent and preliminary flowsheet capable of meeting a target decontamination factor (DF) of 40,000 for worst-case Savannah River Site (SRS) waste with a concentration factor of 15 or higher in the 18-stage equipment configuration of the SRS Modular Caustic-Side Solvent Extraction Unit (MCU). In addition, the NG-CSSX process may be readily adapted for use in the SRS Salt Waste Processing Facility (SWPF) or in supplemental tank-waste treatment at Hanford upon appropriate solvent or flowsheet modifications. Efforts in FY 2010 focused on developing a solvent composition and process flowsheet for MCU implementation. In FY 2011 accomplishments at ORNL involved a wide array of chemical-development activities and testing up through single-stage hydraulic and mass-transfer tests in 5-cm centrifugal contactors. Under subcontract from ORNL, Argonne National Laboratory (ANL) designed a preliminary flowsheet using ORNL cesium distribution data, and Tennessee Technological University confirmed a chemical model for cesium distribution ratios (DCs) as a function of feed composition. Inter laboratory efforts were coordinated with complementary engineering tests carried out (and reported separately) by personnel at Savannah River National Laboratory (SRNL) and Savannah River Remediation (SRR) with helpful advice by Parsons Engineering and General Atomics on aspects of possible SWPF implementation.

Selection and design of solvents

DEFF Research Database (Denmark)

Gani, Rafiqul

and design of solvents will be presented together with application examples. The selection problem is defined as finding known chemicals that match the desired functions of a solvent for a specified set of applications. The design problem is defined as finding the molecular structure (or mixture of molecules....... With increasing interest on issues such as waste, sustainability, environmental impact and green chemistry, the selection and design of solvents have become important problems that need to be addressed during chemical product-process design and development. Systematic methods and tools suitable for selection......) that match the desired functions of a solvent for a specified set of applications. Use of organic chemicals and ionic liquids as solvents will be covered....

Solvent and polymer concentration effects on the surface morphology evolution of immiscible polystyrene/poly(methyl methacrylate) blends

International Nuclear Information System (INIS)

Cui Liang; Ding Yan; Li Xue; Wang Zhe; Han Yanchun

2006-01-01

The effects of solvent nature on the surface topographies of polystyrene (PS)/poly(methyl methacrylate) (PMMA) blend films spin-coated onto the silicon wafer were investigated. Four different solvents, such as ethylbenzene, toluene, tetrahydrofuran and dichloromethane, were chosen. They are better solvents for PS than that for PMMA. When dichloromethane, tetrahydrofuran and toluene were used, PMMA-rich phase domains protruded from the background of PS. When ethylbenzene was used, PS-rich phase domains elevated on the average height of PMMA-rich phase domains. In addition, continuous pits, networks and isolated droplets consisted of PS formed on the blend film surfaces with the decrease of polymer concentrations. The mechanism of the surface morphology evolution was discussed in detail

Hazardous solvent substitution

International Nuclear Information System (INIS)

Twitchell, K.E.

1995-01-01

This article is an overview of efforts at INEL to reduce the generation of hazardous wastes through the elimination of hazardous solvents. To aid in their efforts, a number of databases have been developed and will become a part of an Integrated Solvent Substitution Data System. This latter data system will be accessible through Internet

Clean coal technologies: A business report

International Nuclear Information System (INIS)

Anon.

1993-01-01

The book contains four sections as follows: (1) Industry trends: US energy supply and demand; The clean coal industry; Opportunities in clean coal technologies; International market for clean coal technologies; and Clean Coal Technology Program, US Energy Department; (2) Environmental policy: Clean Air Act; Midwestern states' coal policy; European Community policy; and R ampersand D in the United Kingdom; (3) Clean coal technologies: Pre-combustion technologies; Combustion technologies; and Post-combustion technologies; (4) Clean coal companies. Separate abstracts have been prepared for several sections or subsections for inclusion on the data base

Financing clean energy market creation. Clean energy ventures, venture capitalists and other investors

Energy Technology Data Exchange (ETDEWEB)

Teppo, T. [Helsinki Univ. of Technology, Espoo (Finland). Development and Management in Industry

2006-07-01

Many factors have emerged for change towards cleaner and more efficient technologies and services: climate change, increasing oil demands, and rising living standards in many parts of the world are putting an ever-increasing strain on the environment. Recently, these drivers have fueled the formation of a clean energy venture capital market where both independent venture capitalists (VCs) and corporate venture capitalists (CVCs) have invested in clean energy start-ups. Financing of clean energy market creation is the focus of this dissertation. The dissertation contributes to several bodies of literature in the area of entrepreneurship, new industry creation, corporate venturing, and venture capital research. The dissertation uses a grounded theory approach. The study is guided by three data collection approaches with an emphasis on the first two. First, interviews with European and North American VC and CVC firms that have invested in the clean energy sector were carried out. Second, a clean energy venture financing survey that consisted of qualitative, essay-format questions and some quantitative questions was carried out. Third, interviews with clean energy stakeholders were carried out in order to gain a better understanding of the emerging sector. The research results consist of three main findings. First, the research results suggest that clean energy ventures face the following three main entrepreneurial challenges: financing, market education, and growth management. A further study of three clean energy industry categories revealed additional challenges that varied according to the industry development stage. Second, the results demonstrate that, from a venture capitalist perspective, clean energy venture risk characteristics can be divided into two groups: generally recognized risk characteristics and cognitive risk characteristics. The identified generally recognized risk characteristics were market demand and adaptation, incompatibility with the VC model

Chemical cleaning review

International Nuclear Information System (INIS)

Dow, B.L.; Thomas, R.C.

1995-01-01

Three main chemical processes for cleaning steam generators have evolved from the early work of the industry. Of the more than 50 chemical cleanings carried out to date most have been considered a success by the utilities performing them. (author)

Cleaning and extraction apparatus in a nuclear fuel reprocessing

International Nuclear Information System (INIS)

Nakamura, Yoshiaki.

1983-01-01

Purpose : To eliminate the requirement for the decomposition and cleaning of a centrifugal extractor upon re-processing of FBR type reactor fuels, by preventing solid fission products from depositing on a rotary body of the centrifugal extractor. Constitution : A cleaning and extraction apparatus comprising a combination of a centrifugal cleaner and a centrifugal extractor is used for shortening the contact time between the process liquid and the extraction solvent in FBR type reactor fuel re-processing, and variable parameters are adjusted so that the following equation can be satisfied for avoiding the deposition of solids onto the rotary body of the centrifugal extractor: lsub(e). (rsub(le) 2 + rsub(2r) 2 ) . Nsub(e) . Qsub(c)/ lsub(c) (rsub(lc) 2 + rsub(2c) 2 ) . Nsub(c) . Qsub(e) < 0.8 where Qsub(c) : flow rate to be processed in a centrifugal cleaner, lsub(c) : length of the rotary body, rsub(2c) : radius of a rotary body, rsub(le) : distance from the center to the liquid-extracting hole of the rotary body center to the liquid-extraction hole, Nsub(c) : number of revolution of the rotary body, Qsub(e) : amount of flowrate to be treated in the centrifugal extractor, lsub(e) : length of the rotary body, rsub(2e) : radius for the rotary body, rsub(le) : distance from the center of the rotary body to the liquid discharging aperture and Nsub(e) : number of rotation of the rotary body. (Ikeda, J.)

Organic Solvent Tropical Report

International Nuclear Information System (INIS)

COWLEY, W.L.

2000-01-01

This report provides the basis for closing the organic solvent safety issue. Sufficient information is presented to conclude that risk posed by an unmitigated organic solvent fire is within risk evaluation guidelines

Chemical cleaning of UK AGR boilers

International Nuclear Information System (INIS)

Rudge, A.; Turner, P.; Ghosh, A.; Clary, W.; Tice, D.

2002-01-01

For the first time in their operational lives, UK advanced gas-cooled reactor once-through boilers have been chemically cleaned. Chemical cleaning was necessary to avoid lost output resulting from boiler pressure drops, which had been increasing for a number of years. Chemical cleaning of these boilers presents a number of unique difficulties. These include lack of access to the boilers, highly sensitised 316H superheater sections that cannot be excluded from the cleaning flow path, relatively thin boiler tube walls and an intolerance to boiler tube failure because of the role of the boilers in nuclear decay heat removal. The difficulties were overcome by implementing the clean in a staged manner, starting with an extensive materials testwork programme to select and then to substantiate the cleaning process. The selected process was based on ammoniated citric acid plus formic acid for the principal acid cleaning stage. Materials testwork was followed by an in-plant trial clean of six boiler tubes, further materials testwork and the clean of a boiler tube in a full-scale test rig. An overview is presented of the work that was carried out to demonstrate that the clean could be carried out safely, effectively and without leading to unacceptable corrosion losses. Full-scale chemical cleaning was implemented by using as much of the existing plant as possible. Careful control and monitoring was employed to ensure that the cleaning was implemented according to the specified design, thus ensuring that a safe and effective clean was carried out. Full-scale cleaning has resulted in significant boiler pressure drop recovery, even though the iron burden was relatively low and cleaning was completed in a short time. (orig.)

Extending CO2 cryogenic aerosol cleaning for advanced optical and EUV mask cleaning

Science.gov (United States)

Varghese, Ivin; Bowers, Charles W.; Balooch, Mehdi

2011-11-01

Cryogenic CO2 aerosol cleaning being a dry, chemically-inert and residue-free process is used in the production of optical lithography masks. It is an attractive cleaning option for the mask industry to achieve the requirement for removal of all printable soft defects and repair debris down to the 50nm printability specification. In the technique, CO2 clusters are formed by sudden expansion of liquid from high to almost atmospheric pressure through an optimally designed nozzle orifice. They are then directed on to the soft defects or debris for momentum transfer and subsequent damage free removal from the mask substrate. Unlike aggressive acid based wet cleaning, there is no degradation of the mask after processing with CO2, i.e., no critical dimension (CD) change, no transmission/phase losses, or chemical residue that leads to haze formation. Therefore no restriction on number of cleaning cycles is required to be imposed, unlike other cleaning methods. CO2 aerosol cleaning has been implemented for several years as full mask final clean in production environments at several state of the art mask shops. Over the last two years our group reported successful removal of all soft defects without damage to the fragile SRAF features, zero adders (from the cleaning and handling mechanisms) down to a 50nm printability specification. In addition, CO2 aerosol cleaning is being utilized to remove debris from Post-RAVE repair of hard defects in order to achieve the goal of no printable defects. It is expected that CO2 aerosol cleaning can be extended to extreme ultraviolet (EUV) masks. In this paper, we report advances being made in nozzle design qualification for optimum snow properties (size, velocity and flux) using Phase Doppler Anemometry (PDA) technique. In addition the two new areas of focus for CO2 aerosol cleaning i.e. pellicle glue residue removal on optical masks, and ruthenium (Ru) film on EUV masks are presented. Usually, the residue left over after the pellicle

A clean method for solvent-free nitration of toluene over sulfated titania promoted by ceria catalysts.

Science.gov (United States)

Mao, Wei; Ma, Hongzhu; Wang, Bo

2009-08-15

A mild simple method for nitration of aromatic compounds, various solid acids as catalysts, the air treated with the corona discharge generator as nitrating agent, the liquid-phase nitration of toluene, at ambient temperature and atmospheric pressure without solvent has been investigated. The results show that SO(4)(2-)/TiO(2) (ST) and SO(4)(2-)/TiO(2) doped with CeO(2) (STC) catalysts displayed good nitration activity in the experiments. It is an attractive method for the environmentally friendly synthesis of nitroaromatic compounds. Moreover, only mononitrotoluenes were detected in the products, and the ratio of para-nitrotoluene and ortho-nitrotoluene was approximately 1:1 with various catalysts. A maximum yield of about 11.4% was achieved for mononitrotoluenes in STC reaction system in 3h.

Optimization of co-solvent addition in supercritical fluid extraction of fat with carbon dioxide

Directory of Open Access Journals (Sweden)

Ivanov Dušica S.

2011-01-01

Full Text Available This investigation is concerned with supercritical fluid extraction (SFE using CO2, as an analytical technique for total fat extraction from food and feed samples. Its most significant advantages are safety, cleanness, and shorter extraction time. The main limitation of this technique includes the difficulty of extracting polar lipids due to the non-polar character of the solvent (CO2 used for the extraction. The influence of ethanol as a co-solvent on the SFE of mash pig feed was investigated in this paper. Total fat content was determined by SFE and Soxhlet method for ten commercially available mesh pig feeds. Yields of the fat extracted by both methods were plotted one against the other and compared. Statistically significant difference (p ≤ 0.05 has been found only between the total fat obtained by the Soxhlet extraction and SFE by pure CO2. Based on the mathematical model, maximum yield of the extracted fat is achieved at an ethanol addition of 0.67 ml/g of sample, when the other parameters are the same as recommended by the producer’s procedure.

Background problem for a large solid angle, high sensitivity detector

International Nuclear Information System (INIS)

Chen, M.

1977-01-01

With extremely good vacuum (10 -11 to 10 -13 torr) and well controlled beams, the ISR has a good reputation for clean beam conditions and low background for most types of experiments. However, for a detector covering a large solid angle, measuring processes with small cross sections (approximately 10 -38 cm 2 ) there are serious background problems which took almost a year to solve. Since ISABELLE may have similar problems, a summary is given of experience at the ISR with the hope that some of the solutions can be installed in ISABELLE at an early stage

Insecticide solvents: interference with insecticidal action.

Science.gov (United States)

Brattsten, L B; Wilkinson, C F

1977-06-10

Several commercial solvent mixtures commonly used as insecticide carriers in spray formulations increase by more than threefold the microsomal N-demethylation of p-chloro N-methylaniline in midgut preparations of southern army-worm (Spodoptera eridania) larvae exposed orally to the test solvents. Under laboratory conditions, the same solvent mixtures exhibit a protective action against the in vivo toxicity of the insecticide carbaryl to the larvae. The data are discussed with respect to possible solvent-insecticide interactions occurring under field conditions and, more broadly, to potential toxicological hazards of these solvents to humans.

Steam cleaning device

International Nuclear Information System (INIS)

Karaki, Mikio; Muraoka, Shoichi.

1985-01-01

Purpose: To clean complicated and long objects to be cleaned having a structure like that of nuclear reactor fuel assembly. Constitution: Steams are blown from the bottom of a fuel assembly and soon condensated initially at the bottom of a vertical water tank due to water filled therein. Then, since water in the tank is warmed nearly to the saturation temperature, purified water is supplied from a injection device below to the injection device above the water tank on every device. In this way, since purified water is sprayed successively from below to above and steams are condensated in each of the places, the entire fuel assembly elongated in the vertical direction can be cleaned completely. Water in the reservoir goes upward like the steam flow and is drained together with the eliminated contaminations through an overflow pipe. After the cleaning has been completed, a main steam valve is closed and the drain valve is opened to drain water. (Kawakami, Y.)

Noise-induced hearing loss in Korean workers: co-exposure to organic solvents and heavy metals in nationwide industries.

Directory of Open Access Journals (Sweden)

Yoon-Hyeong Choi

Full Text Available BACKGROUND: Noise exposure is a well-known contributor to work-related hearing loss. Recent biological evidence suggests that exposure to ototoxic chemicals such as organic solvents and heavy metals may be additional contributors to hearing loss. However, in industrial settings, it is difficult to determine the risks of hearing loss due to these chemicals in workplaces accompanied by excessive noise exposure. A few studies suggest that the effect of noise may be enhanced by ototoxic chemicals. Therefore, this study investigated whether co-exposure to organic solvents and/or heavy metals in the workplace modifies the risk of noise exposure on hearing loss in a background of excessive noise. METHODS: We examined 30,072 workers nationwide in a wide range of industries from the Korea National Occupational Health Surveillance 2009. Data on industry-based exposure (e.g., occupational noise, heavy metals, and organic solvents and subject-specific health outcomes (e.g., audiometric examination were collected. Noise was measured as the daily 8-h time-weighted average level. Air conduction hearing thresholds were measured from 0.5 to 6 kHz, and pure-tone averages (PTA (i.e., means of 2, 3, and 4 kHz were computed. RESULTS: In the multivariate linear model, PTA increment with occupational noise were 1.64-fold and 2.15-fold higher in individuals exposed to heavy metals and organic solvents than in unexposed individuals, respectively. CONCLUSION: This study provides nationwide evidence that co-exposure to heavy metals and/or organic solvents may exacerbate the effect of noise exposure on hearing loss in workplaces. These findings suggest that workers in industries dealing with heavy metals or organic solvents are susceptible to such risks.

Ensuring clean air: Developing a clean air strategy for British Columbia

International Nuclear Information System (INIS)

1992-04-01

In 1992, a clean air strategy will be developed to incorporate views of British Columbians on ways to meet goals related to air quality. A discussion paper is presented to provide information to those interested in participation in developing this strategy. The paper gives information on air quality issues important to the province, including local air quality, urban smog, ozone layer depletion, and global climate change. The views and concerns expressed by stakeholders who attended the Clean Air Conference in 1991 are summarized. The process used to develop the clean air strategy is outlined and some outcomes to be anticipated from the strategy are suggested, including policies and priorities for action to ensure clean air. Air pollutants of concern are total reduced sulfur, mainly from pulp mills and gas processing plants; smoke from wood burning; sulfur dioxide from pulp mills and gas plants; hydrogen fluoride from aluminum smelting; ground-level ozone in urban areas; and acid rain. Elements of a clean air strategy include a smoke management policy, management strategies for greenhouse gases and ozone smog, ozone layer protection measures, regional air quality management plans, and long-term planning efforts in energy use, transportation modes, community design, and land use. 12 refs., 14 figs., 2 tabs

''How clean is clean'' in the United States federal and Washington State cleanup regulations

International Nuclear Information System (INIS)

Landau, H.G.

1993-01-01

The enactment of legislation and promulgation of implementing regulations generally involves the resolution of conflicting goals. Defining ''How Clean is Clean?'' in federal and state cleanup laws, regulations, and policies is no exception. Answering the ''How Clean is Clean?'' question has resulted in the identification of some important and sometimes conflicting goals. Continuing resolution of the following conflicting goals is the key to effect cleanup of hazardous waste sites: Expediency vs. Fairness; Flexibility vs. Consistency; Risk Reduction vs. Risk Causation; and Permanence vs. Cost Effectiveness

Benchmarks of Global Clean Energy Manufacturing

Energy Technology Data Exchange (ETDEWEB)

Sandor, Debra [National Renewable Energy Lab. (NREL), Golden, CO (United States); Chung, Donald [National Renewable Energy Lab. (NREL), Golden, CO (United States); Keyser, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Mann, Margaret [National Renewable Energy Lab. (NREL), Golden, CO (United States); Engel-Cox, Jill [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2017-01-01

The Clean Energy Manufacturing Analysis Center (CEMAC), sponsored by the U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE), provides objective analysis and up-to-date data on global supply chains and manufacturing of clean energy technologies. Benchmarks of Global Clean Energy Manufacturing sheds light on several fundamental questions about the global clean technology manufacturing enterprise: How does clean energy technology manufacturing impact national economies? What are the economic opportunities across the manufacturing supply chain? What are the global dynamics of clean energy technology manufacturing?

Next Generation Solvent (NGS): Development for Caustic-Side Solvent Extraction of Cesium

Energy Technology Data Exchange (ETDEWEB)

Moyer, Bruce A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Birdwell, Jr, Joseph F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bonnesen, Peter V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Delmau, Laetitia Helene [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Duncan, Nathan C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ensor, Dale [Tennessee Technological Univ., Cookeville, TN (United States); Hill, Talon G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lee, Denise L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Rajbanshi, Arbin [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Roach, Benjamin D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Szczygiel, Patricia L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Sloop, Jr., Frederick V. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Stoner, Erica L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Williams, Neil J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2014-03-01

This report summarizes the FY 2010 and 2011 accomplishments at Oak Ridge National Laboratory (ORNL) in developing the Next Generation Caustic-Side Solvent Extraction (NG-CSSX) process, referred to commonly as the Next Generation Solvent (NGS), under funding from the U.S. Department of Energy, Office of Environmental Management (DOE-EM), Office of Technology Innovation and Development. The primary product of this effort is a process solvent and preliminary flowsheet capable of meeting a target decontamination factor (DF) of 40,000 for worst-case Savannah River Site (SRS) waste with a concentration factor of 15 or higher in the 18-stage equipment configuration of the SRS Modular Caustic-Side Solvent Extraction Unit (MCU). In addition, the NG-CSSX process may be readily adapted for use in the SRS Salt Waste Processing Facility (SWPF) or in supplemental tank-waste treatment at Hanford upon appropriate solvent or flowsheet modifications. Efforts in FY 2010 focused on developing a solvent composition and process flowsheet for MCU implementation. In FY 2011 accomplishments at ORNL involved a wide array of chemical-development activities and testing up through single-stage hydraulic and mass-transfer tests in 5-cm centrifugal contactors. Under subcontract from ORNL, Argonne National Laboratory (ANL) designed a preliminary flowsheet using ORNL cesium distribution data, and Tennessee Technological University confirmed a chemical model for cesium distribution ratios (DCs) as a function of feed composition. Interlaboratory efforts were coordinated with complementary engineering tests carried out (and reported separately) by personnel at Savannah River National Laboratory (SRNL) and Savannah River Remediation (SRR) with helpful advice by Parsons Engineering and General Atomics on aspects of possible SWPF implementation.

Diamond-cleaning investigations

International Nuclear Information System (INIS)

Derry, T.E.

Four parcels of diamonds which either had or had not been cleaned using the usual techniques, chiefly involving etch in molten potassium nitrate were supplied by De Beers Diamond Research Laboratories. Each parcel contained about 40 stones, amounting to about 10 carats. Half the diamonds in each parcel were cleaned by a standard procedure involving half an hours ultrasonic agitation in a 20% solution of the commercial detergent 'Contrad' which is effectively a surfactant and chelating agent. Visual comparisons by a number of observers who were not told the stones' histories, established that these diamonds generally had a more sparkling appearance after the cleaning procedure had been applied

Keeping condensers clean

Energy Technology Data Exchange (ETDEWEB)

Wicker, K.

2006-04-15

The humble condenser is among the biggest contributors to a steam power plant's efficiency. But although a clean condenser can provide great economic benefit, a dirty one can raise plant heat rate, resulting in large losses of generation revenue and/or unnecessarily high fuel bills. Conventional methods for cleaning fouled tubes range form chemicals to scrapers to brushes and hydro-blasters. This article compares the available options and describes how one power station, Omaha Public Power District's 600 MW North Omaha coal-fired power station, cleaned up its act. The makeup and cooling water of all its five units comes from the Missouri River. 6 figs.

National Alliance for Clean Energy Incubators New Mexico Clean Energy Incubator

Energy Technology Data Exchange (ETDEWEB)

Roberts, Suzanne S.

2004-12-15

The National Alliance for Clean Energy Incubators was established by the National Renewable Energy Laboratory (NREL) to develop an emerging network of business incubators for entrepreneurs specializing in clean energy enterprises. The Alliance provides a broad range of business services to entrepreneurs in specific geographic locales across the U.S. and in diverse clean energy technology areas such as fuel cells, alternative fuels, power generation, and renewables, to name a few. Technology Ventures Corporation (TVC) participates in the Alliance from its corporate offices in Albuquerque, NM, and from its sites in Northern and Southern New Mexico, California, and Nevada. TVC reports on the results of its attempts to accelerate the growth and success of clean energy and energy efficiency companies through its array of business support services. During the period from September 2002 through September 2004, TVC describes contributions to the Alliance including the development of 28 clients and facilitating capital raises exceeding $35M.

Computer Aided Solvent Selection and Design Framework

DEFF Research Database (Denmark)

Mitrofanov, Igor; Conte, Elisa; Abildskov, Jens

and computer-aided tools and methods for property prediction and computer-aided molecular design (CAMD) principles. This framework is applicable for solvent selection and design in product design as well as process design. The first module of the framework is dedicated to the solvent selection and design...... in terms of: physical and chemical properties (solvent-pure properties); Environment, Health and Safety (EHS) characteristic (solvent-EHS properties); operational properties (solvent–solute properties). 3. Performing the search. The search step consists of two stages. The first is a generation and property...... identification of solvent candidates using special software ProCAMD and ProPred, which are the implementations of computer-aided molecular techniques. The second consists of assigning the RS-indices following the reaction–solvent and then consulting the known solvent database and identifying the set of solvents...

Improvements in solvent extraction columns

International Nuclear Information System (INIS)

Aughwane, K.R.

1987-01-01

Solvent extraction columns are used in the reprocessing of irradiated nuclear fuel. For an effective reprocessing operation a solvent extraction column is required which is capable of distributing the feed over most of the column. The patent describes improvements in solvent extractions columns which allows the feed to be distributed over an increased length of column than was previously possible. (U.K.)

Desorption atmospheric pressure photoionization with polydimethylsiloxane as extraction phase and sample plate material

International Nuclear Information System (INIS)

Vaikkinen, A.; Kotiaho, T.; Kostiainen, R.; Kauppila, T.J.

2010-01-01

Desorption atmospheric pressure photoionization (DAPPI) is an ambient ionization technique for mass spectrometry (MS) that can be used to ionize polar as well as neutral and completely non-polar analytes. In this study polydimethylsiloxane (PDMS) was used as a solid phase extraction sorbent for DAPPI-MS analysis. Pieces of PDMS polymer were soaked in an aqueous sample, where the analytes were sorbed from the sample solution to PDMS. After this, the extracted analytes were desorbed directly from the polymer by the hot DAPPI spray solvent plume, without an elution step. Swelling and extracting the PDMS with a cleaning solvent prior to extraction diminished the high background in the DAPPI mass spectrum caused by PDMS oligomers. Acetone, hexane, pentane, toluene, diisopropylamine and triethylamine were tested for this purpose. The amines were most efficient in reducing the PDMS background, but they also suppressed the signals of low proton affinity analytes. Toluene was chosen as the optimum cleaning solvent, since it reduced the PDMS background efficiently and gave intensive signals of most of the studied analytes. The effects of DAPPI spray solvents toluene, acetone and anisole on the PDMS background and the ionization of analytes were also compared and extraction conditions were optimized. Anisole gave a low background for native PDMS, but toluene ionized the widest range of analytes. Analysis of verapamil, testosterone and anthracene from purified, spiked wastewater was performed to demonstrate that the method is suited for in-situ analysis of water streams. In addition, urine spiked with several analytes was analyzed by the PDMS method and compared to the conventional DAPPI procedure, where sample droplets are applied on PMMA surface. With the PDMS method the background ion signals caused by the urine matrix were lower, the S/N ratios of analytes were 2-10 times higher, and testosterone, anthracene and benzo[a]pyrene that were not detected from PMMA in urine

Desorption atmospheric pressure photoionization with polydimethylsiloxane as extraction phase and sample plate material

Energy Technology Data Exchange (ETDEWEB)

Vaikkinen, A. [Division of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FIN-00014 University of Helsinki (Finland); Kotiaho, T. [Division of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FIN-00014 University of Helsinki (Finland); Laboratory of Analytical Chemistry, Department of Chemistry, P.O. Box 55, FIN-00014 University of Helsinki (Finland); Kostiainen, R. [Division of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FIN-00014 University of Helsinki (Finland); Kauppila, T.J., E-mail: tiina.kauppila@helsinki.fi [Division of Pharmaceutical Chemistry, Faculty of Pharmacy, P.O. Box 56, FIN-00014 University of Helsinki (Finland)

2010-12-03

Desorption atmospheric pressure photoionization (DAPPI) is an ambient ionization technique for mass spectrometry (MS) that can be used to ionize polar as well as neutral and completely non-polar analytes. In this study polydimethylsiloxane (PDMS) was used as a solid phase extraction sorbent for DAPPI-MS analysis. Pieces of PDMS polymer were soaked in an aqueous sample, where the analytes were sorbed from the sample solution to PDMS. After this, the extracted analytes were desorbed directly from the polymer by the hot DAPPI spray solvent plume, without an elution step. Swelling and extracting the PDMS with a cleaning solvent prior to extraction diminished the high background in the DAPPI mass spectrum caused by PDMS oligomers. Acetone, hexane, pentane, toluene, diisopropylamine and triethylamine were tested for this purpose. The amines were most efficient in reducing the PDMS background, but they also suppressed the signals of low proton affinity analytes. Toluene was chosen as the optimum cleaning solvent, since it reduced the PDMS background efficiently and gave intensive signals of most of the studied analytes. The effects of DAPPI spray solvents toluene, acetone and anisole on the PDMS background and the ionization of analytes were also compared and extraction conditions were optimized. Anisole gave a low background for native PDMS, but toluene ionized the widest range of analytes. Analysis of verapamil, testosterone and anthracene from purified, spiked wastewater was performed to demonstrate that the method is suited for in-situ analysis of water streams. In addition, urine spiked with several analytes was analyzed by the PDMS method and compared to the conventional DAPPI procedure, where sample droplets are applied on PMMA surface. With the PDMS method the background ion signals caused by the urine matrix were lower, the S/N ratios of analytes were 2-10 times higher, and testosterone, anthracene and benzo[a]pyrene that were not detected from PMMA in urine

Gas separation by composite solvent-swollen membranes

Science.gov (United States)

Matson, Stephen L.; Lee, Eric K. L.; Friesen, Dwayne T.; Kelly, Donald J.

1989-01-01

There is disclosed a composite immobulized liquid membrane of a solvent-swollen polymer and a microporous organic or inorganic support, the solvent being at least one highly polar solvent containing at least one nitrogen, oxygen, phosphorous or sulfur atom, and having a boiling point of at least 100.degree. C. and a specified solubility parameter. The solvent or solvent mixture is homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. The membrane is suitable for acid gas scrubbing and oxygen/nitrogen separation.

Gas separation by composite solvent-swollen membranes

Science.gov (United States)

Matson, S.L.; Lee, E.K.L.; Friesen, D.T.; Kelly, D.J.

1989-04-25

There is disclosed a composite immobilized liquid membrane of a solvent-swollen polymer and a microporous organic or inorganic support, the solvent being at least one highly polar solvent containing at least one nitrogen, oxygen, phosphorus or sulfur atom, and having a boiling point of at least 100 C and a specified solubility parameter. The solvent or solvent mixture is homogeneously distributed through the solvent-swollen polymer from 20% to 95% by weight. The membrane is suitable for acid gas scrubbing and oxygen/nitrogen separation. 3 figs.

Sustainable development with clean coal

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-08-01

This paper discusses the opportunities available with clean coal technologies. Applications include new power plants, retrofitting and repowering of existing power plants, steelmaking, cement making, paper manufacturing, cogeneration facilities, and district heating plants. An appendix describes the clean coal technologies. These include coal preparation (physical cleaning, low-rank upgrading, bituminous coal preparation); combustion technologies (fluidized-bed combustion and NOx control); post-combustion cleaning (particulate control, sulfur dioxide control, nitrogen oxide control); and conversion with the integrated gasification combined cycle.

Clean Energy Progress Report

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

For the past several years, the IEA and others have been calling for a clean energy revolution to achieve global energy security, economic growth and climate change goals. This report analyses for the first time progress in global clean energy technology deployment against the pathways that are needed to achieve these goals. It provides an overview of technology deployment status, key policy developments and public spending on RDD&D of clean energy technologies.

Polonium-210 assay using a background-rejecting extractive liquid-scintillation method

International Nuclear Information System (INIS)

Case, C.N.; McDowell, W.J.

1981-01-01

This paper describes a procedure which combines solvent extraction with alpha liquid scintillation spectrometry. Pulse shape discrimination electronics are used to reject beta and gamma pulses and to lower the background count to acceptable levels. Concentration of 210 Po and separation from interferring elements are accomplished using a H 3 Po 4 -HCl solution with TOPO combined with a scintillor in toluene

Upgrading of brown coal by slurry-dewatering; Kattan no yuchu dassui ni yoru clean kotai nenryo no seizo

Energy Technology Data Exchange (ETDEWEB)

Okuma, O.; Shimizu, T.; Inoue, T.; Shigehisa, T.; Deguchi, T.; Katsushima, S. [Kobe Steel, Ltd., Kobe (Japan)

1996-10-28

This paper describes an outline of solid fuel production process from brown coal and the investigation results of its elemental techniques. Dried coal is produced by this process which consists of a dewatering of crushed brown coal in oil-based solvent, a solid and liquid separation of slurry, and a remained oil recovery by heating. This process is characterized by the higher thermal efficiency compared with usual drying and the restraint of spontaneous combustion of product coal. It was revealed that solid fuel with low moisture, low ash, low sulfur, and suppressed spontaneous combustion property can be produced from Australian brown coal through this process. From the comparison between kerosene and fuel oil A, it was confirmed that the oil content during dewatering was smaller and the oil recovery by heating was easier by using a solvent with lower boiling point. It was also confirmed that the spontaneous combustion property can be suppressed using small amount of asphalt by solving asphalt in the solvent and adsorbing asphalt on the surface of brown coal. From these results, low rank coals including brown coal, which are difficult to use, are expected to be used as clean coal with low ash and low sulfur through this process. 2 refs., 7 figs., 2 tabs.

Clean-in-Place and Reliability Testing of a Commercial 12.5-cm Annular Centrifugal Contactor at the INL

International Nuclear Information System (INIS)

N. R. Mann; T. G. Garn; D. H. Meikrantz; J. D. Law; T. A. Todd

2007-01-01

The renewed interest in advancing nuclear energy has spawned the research of advanced technologies for recycling nuclear fuel. A significant portion of the advanced fuel cycle includes the recovery of selected actinides by solvent extraction methods utilizing centrifugal contactors. Although the use of centrifugal contactors for solvent extraction is widely known, their operation is not without challenges. Solutions generated from spent fuel dissolution contain unknown quantities of undissolved solids. A majority of these solids will be removed via various methods of filtration. However, smaller particles are expected to carry through to downstream solvent extraction processes and equipment. In addition, solids/precipitates brought about by mechanical or chemical upsets are another potential area of concern. During processing, particulate captured in the rotor assembly by high centrifugal forces eventually forms a cake-like structure on the inner wall introducing balance problems and negatively affecting phase separations. One of the features recently developed for larger engineering scale Annular Centrifugal Contactors (ACCs) is the Clean-In-Place (CIP) capability. Engineered spray nozzles were installed into the hollow central rotor shaft in all four quadrants of the rotor assembly. This arrangement allows for a very convenient and effective method of solids removal from within the rotor assembly

Clean-in-Place and Reliability Testing of a Commercial 12.5 cm Annular Centrifugal Contactor at the INL

International Nuclear Information System (INIS)

N. R. Mann; T. G. Garn; D. H. Meikrantz; J. D. Law; T. A. Todd

2007-01-01

The renewed interest in advancing nuclear energy has spawned the research of advanced technologies for recycling nuclear fuel. A significant portion of the advanced fuel cycle includes the recovery of selected actinides by solvent extraction methods utilizing centrifugal contactors. Although the use of centrifugal contactors for solvent extraction is widely known, their operation is not without challenges. Solutions generated from spent fuel dissolution contain unknown quantities of undissolved solids. A majority of these solids will be removed via various methods of filtration. However, smaller particles are expected to carry through to downstream solvent extraction processes and equipment. In addition, solids/precipitates brought about by mechanical or chemical upsets are another potential area of concern. During processing, particulate captured in the rotor assembly by high centrifugal forces eventually forms a cake-like structure on the inner wall introducing balance problems and negatively affecting phase separations. One of the features recently developed for larger engineering scale Annular Centrifugal Contactors (ACCs) is the Clean-In-Place (CIP) capability. Engineered spray nozzles were installed into the hollow central rotor shaft in all four quadrants of the rotor assembly. This arrangement allows for a very convenient and effective method of solids removal from within the rotor assembly

Alternative solvents for natural products extraction

CERN Document Server

Chemat, Farid

2014-01-01

This book presents a complete picture of the current state-of-the-art in alternative and green solvents used for laboratory and industrial natural product extraction in terms of the latest innovations, original methods and safe products. It provides the necessary theoretical background and details on extraction, techniques, mechanisms, protocols, industrial applications, safety precautions and environmental impacts. This book is aimed at professionals from industry, academicians engaged in extraction engineering or natural product chemistry research, and graduate level students. The individual chapters complement one another, were written by respected international researchers and recognized professionals from the industry, and address the latest efforts in the field. It is also the first sourcebook to focus on the rapid developments in this field.

Processing of polymers using reactive solvents

NARCIS (Netherlands)

Lemstra, P.J.; Kurja, J.; Meijer, H.E.H.; Meijer, H.E.H.

1997-01-01

A review with many refs. on processing of polymers using reactive solvents including classification of synthetic polymers, guidelines for the selection of reactive solvents, basic aspects of processing, examples of intractable and tractable polymer/reactive solvent system

40 CFR Table 4 to Subpart Oooo of... - Default Organic HAP Mass Fraction for Solvents and Solvent Blends

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Default Organic HAP Mass Fraction for... 63—Default Organic HAP Mass Fraction for Solvents and Solvent Blends You may use the mass fraction... formulation data. Solvent/solvent blend CAS. No. Averageorganic HAP mass fraction Typical organic HAP, percent...

The "F" in SAFE: Reliability of assessing clean faces for trachoma control in the field.

Directory of Open Access Journals (Sweden)

Sheila K West

2017-11-01

Full Text Available Although facial cleanliness is part of the SAFE strategy for trachoma there is controversy over the reliability of measuring a clean face. A child's face with no ocular and nasal discharge is clean and the endpoint of interest, regardless of the number of times it must be washed to achieve that endpoint. The issue of reliability rests on the reproducibility of graders to assess a clean face. We report the reproducibility of assessing a clean face in a field trial in Kongwa, Tanzania.Seven graders were trained to assess the presence and absence of nasal and ocular discharge on children's faces. Sixty children ages 1-7 years were recruited from a community and evaluated independently by seven graders, once and again about 50 minutes later. Intra-and inter-observer variation was calculated using unweighted kappa statistics. The average intra-observer agreement was kappa = 0.72, and the average inter-observer agreement was kappa = 0.78.Intra-observer and inter-observer agreement was substantial for the assessment of clean faces using trained Tanzania staff who represent a variety of educational backgrounds. As long as training is provided, the estimate of clean faces in children should be reliable, and reflect the effort of families to keep ocular and nasal discharge off the faces. These data suggest assessment of clean faces could be added to trachoma surveys, which already measure environmental improvements, in districts.

Effects of solvent and structure on the reactivity of 6-substituted nicotinic acids with diazodiphenylmethane in aprotic solvents

Directory of Open Access Journals (Sweden)

BRATISLAV Ž. JOVANOVIĆ

2009-12-01

Full Text Available The rate constants for the reactions of diazodiphenylmethane (DDM with 6-substituted nicotinic acids in aprotic solvents at 30 °C were determined. The obtained second order rate constants in aprotic solvents, together with literature data for benzoic and nicotinic acids in protic solvents, were used for the calculation of solvent effects, employing the Kamlet-Taft solvatochromic equation (linear solvation energy relationship – LSER in the form: log k = log k0 + s* + a + b. The correlations of the kinetic data were performed by means of multiple linear regression analysis taking appropriate solvent parameters. The sign of the equation coefficients (s, a and b were in agreement with the postulated reaction mechanism, and the mode of the solvent influences on the reaction rate is discussed based on the correlation results. A similar contribution of the non-specific solvent effect and electrophilic solvation was observed for all acids, while the highest contribution of nucleophilic solvation was influenced by their high acidity. Correlation analysis of the rate data with substituent p parameters in an appropriate solvent using the Hammett equation was also performed. The substituent effect on the acid reactivity was higher in aprotic solvents of higher dipolarity/polarizability. The mode of the transmission of the substituent effect is discussed in light of the contribution of solute–solvent interaction on the acid reactivity.

Clean Energy Policy Analysis: Impact Analysis of Potential Clean Energy Policy Options for the Hawaii Clean Energy Initiative (HCEI)

Energy Technology Data Exchange (ETDEWEB)

Busche, S.; Doris, E.; Braccio, R.; Lippert, D.; Finch, P.; O' Toole, D.; Fetter, J.

2010-04-01

This report provides detailed analyses of 21 clean energy policy options considered by the Hawaii Clean Energy Initiative working groups for recommendation to the 2010 Hawaii State Legislature. The report considers the impact each policy may have on ratepayers, businesses, and the state in terms of energy saved, clean energy generated, and the financial costs and benefits. The analyses provide insight into the possible impacts, both qualitative and quantitative, that these policies may have in Hawaii based on the experience with these policies elsewhere. As much as possible, the analyses incorporate Hawaii-specific context to reflect the many unique aspects of energy use in the State of Hawaii.

Laser cleaning of Rakowicze sandstone

NARCIS (Netherlands)

Nijland, T.G.; Wijffels, T.J.

2003-01-01

Decisions about the cleaning of natural stone should always be made within the awareness of direct and indirect damage that may be the result of cleaning. During the last decade, laser cleaning of objects and monuments of natural stone has become increasingly popular. Whereas a considerable amount

40 CFR Table 3 to Subpart IIIi of... - Default Organic HAP Mass Fraction for Solvents and Solvent Blends

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Default Organic HAP Mass Fraction for... Organic HAP Mass Fraction for Solvents and Solvent Blends You may use the mass fraction values in the... Solvent/solvent blend CAS. No. Averageorganic HAP mass fraction Typical organic HAP, percent by mass 1...

40 CFR Table 5 to Subpart Qqqq of... - Default Organic HAP Mass Fraction for Solvents and Solvent Blends

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Default Organic HAP Mass Fraction for... HAP Mass Fraction for Solvents and Solvent Blends You may use the mass fraction values in the.... Solvent/solvent blend CAS. No. Average organic HAP mass fraction Typical organic HAP, percent by mass 1...

Cosmic microwave background science at commercial airline altitudes

Science.gov (United States)

Feeney, Stephen M.; Gudmundsson, Jon E.; Peiris, Hiranya V.; Verde, Licia; Errard, Josquin

2017-07-01

Obtaining high-sensitivity measurements of degree-scale cosmic microwave background (CMB) polarization is the most direct path to detecting primordial gravitational waves. Robustly recovering any primordial signal from the dominant foreground emission will require high-fidelity observations at multiple frequencies, with excellent control of systematics. We explore the potential for a new platform for CMB observations, the Airlander 10 hybrid air vehicle, to perform this task. We show that the Airlander 10 platform, operating at commercial airline altitudes, is well suited to mapping frequencies above 220 GHz, which are critical for cleaning CMB maps of dust emission. Optimizing the distribution of detectors across frequencies, we forecast the ability of Airlander 10 to clean foregrounds of varying complexity as a function of altitude, demonstrating its complementarity with both existing (Planck) and ongoing (C-BASS) foreground observations. This novel platform could play a key role in defining our ultimate view of the polarized microwave sky.

Solubility of daidzin in different organic solvents and (ethyl alcohol + water) mixed solvents

International Nuclear Information System (INIS)

Fan, Jie-Ping; Yang, Dan; Xu, Xiao-Kang; Guo, Xiao-Jie; Zhang, Xue-Hong

2015-01-01

Highlights: • The solubilities of daidzin were measured in various solvents. • The solubility data were correlated by three models. • The thermodynamic properties of the dissolution process were also determined. - Abstract: The solubility of daidzin in different organic solvents and (ethyl alcohol + water) mixed solvents was measured by high performance liquid chromatography (HPLC) analysis method from T = (283.2 to 323.2) K at atmosphere pressure. The results show that at higher temperature more daidzin dissolves, and moreover, the solubility increases with the ethyl alcohol mole fraction increase in the (ethyl alcohol + water) mixed solvents. The experimental solubility values were correlated by a simplified thermodynamic equation, λh equation and modified Apelblat equation. Based on the solubility of daidzin, the enthalpy and entropy of solution were also evaluated by van’t Hoff equation. The results illustrated that the dissolution process of daidzin is endothermic and entropy driven

Surface cleaning in thin film technology

International Nuclear Information System (INIS)

Mattox, D.M.

1978-01-01

A ''clean surface'' is one that contains no significant amounts of undesirable material. This paper discusses the types and origin of various contaminants. Since cleaning is often equated with adhesion, the mechanisms of adhesion to oxide, metal, and organic surfaces are reviewed and cleaning processes for these surfaces are outlined. Techniques for monitoring surface cleaning are presented, and the importance of storage of clean surfaces is discussed. An extensive bibliography is given. 4 figs., 89 references

Synthesis of (E-2-Styrylchromones and Flavones by Base-Catalyzed Cyclodehydration of the Appropriate β-Diketones Using Water as Solvent

Directory of Open Access Journals (Sweden)

Joana Pinto

2015-06-01

Full Text Available A low cost, safe, clean and environmentally benign base-catalyzed cyclodehydration of appropriate β-diketones affording (E-2-styrylchromones and flavones in good yields is disclosed. Water was used as solvent and the reactions were heated using classical and microwave heating methods, under open and closed vessel conditions. β-Diketones having electron-donating and withdrawing substituents were used to evaluate the reaction scope. The reaction products were isolated in high purity by simple filtration and recrystallization from ethanol, when using 800 mg of the starting diketone under classical reflux heating conditions.

Fire protection for clean rooms

International Nuclear Information System (INIS)

Kirson, D.

1990-01-01

The fire protection engineer often must decide what size fire can be tolerated before automatic fire suppression systems actuate. Is it a wastepaper basket fire, a bushel basket fire...? In the case of state-of-the-art clean rooms, the answer clearly is not even an incipient fire. Minor fires in clean rooms can cause major losses. This paper discusses what a clean room is and gives a brief overview of the unique fire protection challenges encountered. The two major causes of fire related to clean rooms in the semiconductor industry are flammable/pyrophoric gas fires in plastic ducts and polypropylene wet bench fires. This paper concentrates on plastic ductwork in clean rooms, sprinkler protection in ductwork, and protection for wet benches

Improving the Psychosocial Work Environment at Multi-Ethnic Workplaces: A Multi-Component Intervention Strategy in the Cleaning Industry

OpenAIRE

Smith, Louise Hardman; Hviid, Kirsten; Frydendall, Karen Bo; Flyvholm, Mari-Ann

2013-01-01

Global labour migration has increased in recent years and immigrant workers are often recruited into low status and low paid jobs such as cleaning. Research in a Danish context shows that immigrants working in the cleaning industry often form social networks based on shared languages and backgrounds, and that conflict between different ethnic groups may occur. This paper evaluates the impact of a multi-component intervention on the psychosocial work environment at a multi-ethnic Danish workpl...

Adaptive Resolution Simulation of MARTINI Solvents

NARCIS (Netherlands)

Zavadlav, Julija; Melo, Manuel N.; Cunha, Ana V.; de Vries, Alex H.; Marrink, Siewert J.; Praprotnik, Matej

We present adaptive resolution dynamics simulations of aqueous and apolar solvents coarse-grained molecular models that are compatible with the MARTINI force field. As representatives of both classes solvents we have chosen liquid water and butane, respectively, at ambient temperature. The solvent

Green and Bio-Based Solvents.

Science.gov (United States)

Calvo-Flores, Francisco G; Monteagudo-Arrebola, María José; Dobado, José A; Isac-García, Joaquín

2018-04-24

Chemical reactions and many of the procedures of separation and purification employed in industry, research or chemistry teaching utilize solvents massively. In the last decades, with the birth of Green Chemistry, concerns about the employment of solvents and the effects on human health, as well as its environmental impacts and its dependence on non-renewable raw materials for manufacturing most of them, has drawn the attention of the scientific community. In this work, we review the concept of green solvent and the properties and characteristics to be considered green. Additionally, we discuss the different possible routes to prepare many solvents from biomass, as an alternative way to those methods currently applied in the petrochemical industry.

7 CFR 51.2083 - Clean.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Clean. 51.2083 Section 51.2083 Agriculture Regulations... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States Standards for Grades of Almonds in the Shell Definitions § 51.2083 Clean. Clean means that the shell is...

Dry-cleaning of graphene

International Nuclear Information System (INIS)

Algara-Siller, Gerardo; Lehtinen, Ossi; Kaiser, Ute; Turchanin, Andrey

2014-01-01

Studies of the structural and electronic properties of graphene in its pristine state are hindered by hydrocarbon contamination on the surfaces. Also, in many applications, contamination reduces the performance of graphene. Contamination is introduced during sample preparation and is adsorbed also directly from air. Here, we report on the development of a simple dry-cleaning method for producing large atomically clean areas in free-standing graphene. The cleanness of graphene is proven using aberration-corrected high-resolution transmission electron microscopy and electron spectroscopy

Dry-cleaning of graphene

Energy Technology Data Exchange (ETDEWEB)

Algara-Siller, Gerardo [Central Facility for Electron Microscopy, Group of Electron Microscopy of Materials Science, Ulm University, Albert-Einstein-Allee 11, Ulm 89081 (Germany); Department of Chemistry, Technical University Ilmenau, Weimarer Strasse 25, Ilmenau 98693 (Germany); Lehtinen, Ossi; Kaiser, Ute, E-mail: ute.kaiser@uni-ulm.de [Central Facility for Electron Microscopy, Group of Electron Microscopy of Materials Science, Ulm University, Albert-Einstein-Allee 11, Ulm 89081 (Germany); Turchanin, Andrey [Faculty of Physics, University of Bielefeld, Universitätsstr. 25, Bielefeld 33615 (Germany)

2014-04-14

Studies of the structural and electronic properties of graphene in its pristine state are hindered by hydrocarbon contamination on the surfaces. Also, in many applications, contamination reduces the performance of graphene. Contamination is introduced during sample preparation and is adsorbed also directly from air. Here, we report on the development of a simple dry-cleaning method for producing large atomically clean areas in free-standing graphene. The cleanness of graphene is proven using aberration-corrected high-resolution transmission electron microscopy and electron spectroscopy.

System and method for treatment of a flue gas

Science.gov (United States)

Spiry, Irina Pavlovna; Wood, Benjamin Rue; Singh, Surinder Prabhjot; Perry, Robert James; McDermott, John Brian

2017-09-19

A method for treatment of a flue gas involves feeding the flue gas and a lean solvent to an absorber. The method further involves reacting the flue gas with the lean solvent within the absorber to generate a clean flue gas and a rich solvent. The method also involves feeding the clean flue gas from the absorber and water from a source, to a wash tower to separate a stripped portion of the lean solvent from the clean flue gas to generate a washed clean flue gas and a mixture of the water and the stripped portion of the lean solvent. The method further involves treating at least a portion of the mixture of the water and the stripped portion of the lean solvent via a separation system to separate the water from the stripped portion of the lean solvent.

Efficient methods of piping cleaning

Directory of Open Access Journals (Sweden)

Orlov Vladimir Aleksandrovich

2014-01-01

Full Text Available The article contains the analysis of the efficient methods of piping cleaning of water supply and sanitation systems. Special attention is paid to the ice cleaning method, in course of which biological foil and various mineral and organic deposits are removed due to the ice crust buildup on the inner surface of water supply and drainage pipes. These impurities are responsible for the deterioration of the organoleptic properties of the transported drinking water or narrowing cross-section of drainage pipes. The co-authors emphasize that the use of ice compared to other methods of pipe cleaning has a number of advantages due to the relative simplicity and cheapness of the process, economical efficiency and lack of environmental risk. The equipment for performing ice cleaning is presented, its technological options, terms of cleansing operations, as well as the volumes of disposed pollution per unit length of the water supply and drainage pipelines. It is noted that ice cleaning requires careful planning in the process of cooking ice and in the process of its supply in the pipe. There are specific requirements to its quality. In particular, when you clean drinking water system the ice applied should be hygienically clean and meet sanitary requirements.In pilot projects, in particular, quantitative and qualitative analysis of sediments adsorbed by ice is conducted, as well as temperature and the duration of the process. The degree of pollution of the pipeline was estimated by the volume of the remote sediment on 1 km of pipeline. Cleaning pipelines using ice can be considered one of the methods of trenchless technologies, being a significant alternative to traditional methods of cleaning the pipes. The method can be applied in urban pipeline systems of drinking water supply for the diameters of 100—600 mm, and also to diversion collectors. In the world today 450 km of pipelines are subject to ice cleaning method.Ice cleaning method is simple

Solvent Extraction of Furfural From Biomass

Science.gov (United States)

Humphrey, M. F.

1984-01-01

Solvent-extraction method reduces energy required to remove furfural produced during acid hydrolysis of biomass. Acid hydrolysis performed in vessel containing both solvents and reacting ingredients. With intimate contact between solvents and aqueous hydrolyis liqour, furfural removed form liquor almost as fast as it forms.

Biodiesel production from ethanolysis of palm oil using deep eutectic solvent (DES) as co-solvent

Science.gov (United States)

Manurung, R.; Winarta, A.; Taslim; Indra, L.

2017-06-01

Biodiesel produced from ethanolysis is more renewable and have better properties (higher oxidation stability, lower cloud and pour point) compared to methanolysis, but it has a disadvantage such as complicated purification. To improve ethanolysis process, deep eutectic solvent (DES) can be prepared from choline chloride and glycerol and used as co-solvent in ethanolysis. The deep eutectic solvent is formed from a quaternary ammonium salt (choline chloride) and a hydrogen bond donor (Glycerol), it is a non-toxic, biodegradable solvent compared to a conventional volatile organic solvent such as hexane. The deep eutectic solvent is prepared by mixing choline chloride and glycerol with molar ratio 1:2 at temperature 80 °C, stirring speed 300 rpm for 1 hour. The DES is characterized by its density and viscosity. The ethanolysis is performed at a reaction temperature of 70 °C, ethanol to oil molar ratio of 9:1, potassium hydroxide as catalyst concentration of 1.2 wt. DES as co-solvent with concentration 0.5 to 3 wt. stirring speed 400 rpm, and a reaction time 1 hour. The obtained biodiesel is then characterized by its density, viscosity, and ester content. The oil - ethanol phase condition is observed in the reaction tube. The oil - ethanol phase with DES tends to form meniscus compared to without DES, showed that oil and ethanol become more slightly miscible, which favors the reaction. Using DES as co-solvent in ethanolysis showed increasing in yield and easier purification. The esters properties meet the international standards ASTM D6751, with the highest yield achieved 83,67 with 99,77 conversion at DES concentration 2 . Increasing DES concentration above 2 in ethanolysis decrease the conversion and yield, because of the excessive glycerol in the systems makes the reaction equilibrium moves to the reactant side.

Experimental control of the solvent load of inductively coupled argon plasmas and effects of the chloroform plasma load on their analytical performance

Science.gov (United States)

Maessen, F. J. M. J.; Kreuning, G.; Balke, J.

The solvent plasma load ( QSPL) of water, methanol and chloroform was established as a function of the liquid uptake rate ( QL) by using a continuous weighing method for recording the rate differences between the relevant liquid streams. The shape of the QL vs QSPL curves revealed that the liquid uptake rate is a parameter much too insensitive to serve as a criterion for assessing the stability of "organic" plasmas. The quantity "maximum tolerable solvent plasma load" is suggested as a more useful criterion. Effects of rf power, observation height and solvent plasma load on the properties of chloroform inductively coupled plasmas (ICPs) are reported. The measurement of the axial distribution of net line intensities of representative spectral lines showed that the behaviour of emission lines as to their "hardness" is essentially the same in ICPs loaded with chloroform or water. The chloroform plasma load was regulated by the use of a condenser of which the temperature was varied in a range between -50°C and +20°C. Analytical performance characteristics such as net line and background intensities, signal-to-background ratios, and relative standard deviations of the background signal are presented for ICPs with various chloroform loads. Two sets of experimental conditions were finally selected for simultaneous multielement analysis of chloroform solvent solutions, one with and one without aerosol cooling. In the case that aerosol cooling was applied, the detection limits were similar to those for aqueous plasmas. Without aerosol cooling the detection limits were up to an order of magnitude poorer. An attempt has been made to catagorize organic solvents on the basis of both volatility and their behaviour in ICP systems. For a better understanding of the consequences of solvent volatility in ICP-AES it is of importance to consider separately the properties that determine the volatility of liquids, viz. the evaporation rate and the saturation vapour pressure.

Organic Solvent Tolerant Lipases and Applications

Directory of Open Access Journals (Sweden)

Shivika Sharma

2014-01-01

Full Text Available Lipases are a group of enzymes naturally endowed with the property of performing reactions in aqueous as well as organic solvents. The esterification reactions using lipase(s could be performed in water-restricted organic media as organic solvent(s not only improve(s the solubility of substrate and reactant in reaction mixture but also permit(s the reaction in the reverse direction, and often it is easy to recover the product in organic phase in two-phase equilibrium systems. The use of organic solvent tolerant lipase in organic media has exhibited many advantages: increased activity and stability, regiospecificity and stereoselectivity, higher solubility of substrate, ease of products recovery, and ability to shift the reaction equilibrium toward synthetic direction. Therefore the search for organic solvent tolerant enzymes has been an extensive area of research. A variety of fatty acid esters are now being produced commercially using immobilized lipase in nonaqueous solvents. This review describes the organic tolerance and industrial application of lipases. The main emphasis is to study the nature of organic solvent tolerant lipases. Also, the potential industrial applications that make lipases the biocatalysts of choice for the present and future have been presented.

Acetone-based cellulose solvent.

Science.gov (United States)

Kostag, Marc; Liebert, Tim; Heinze, Thomas

2014-08-01

Acetone containing tetraalkylammonium chloride is found to be an efficient solvent for cellulose. The addition of an amount of 10 mol% (based on acetone) of well-soluble salt triethyloctylammonium chloride (Et3 OctN Cl) adjusts the solvent's properties (increases the polarity) to promote cellulose dissolution. Cellulose solutions in acetone/Et3 OctN Cl have the lowest viscosity reported for comparable aprotic solutions making it a promising system for shaping processes and homogeneous chemical modification of the biopolymer. Recovery of the polymer and recycling of the solvent components can be easily achieved. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Computer-aided tool for solvent selection in pharmaceutical processes: Solvent swap

DEFF Research Database (Denmark)

Papadakis, Emmanouil; K. Tula, Anjan; Gernaey, Krist V.

-liquid equilibria). The application of the developed model-based framework is highlighted through several cases studies published in the literature. In the current state, the framework is suitable for problems where the original solvent is exchanged by distillation. A solvent selection guide for fast of suitable......-aided framework with the objective to assist the pharmaceutical industry in gaining better process understanding. A software interface to improve the usability of the tool has been created also....

The grey areas in soil pollution risk mapping : The distinction between cases of soil pollution and increased background levels

NARCIS (Netherlands)

Gaast, N. van der; Leenaers, H.; Zegwaard, J.

1998-01-01

The progress of soil clean up in the Netherlands is severely hindered by the lack of common agreement on how to describe the grey areas of increased background levels of pollutants. In this study practical methods are proposed in which background levels are described as distribution functions within

Effects of solvent evaporation conditions on solvent vapor annealed cylinder-forming block polymer thin films

Science.gov (United States)

Grant, Meagan; Jakubowski, William; Nelson, Gunnar; Drapes, Chloe; Baruth, A.

Solvent vapor annealing is a less time and energy intensive method compared to thermal annealing, to direct the self-assembly of block polymer thin films. Periodic nanostructures have applications in ultrafiltration, magnetic arrays, or other structures with nanometer dimensions, driving its continued interest. Our goal is to create thin films with hexagonally packed, perpendicular aligned cylinders of poly(lactide) in a poly(styrene) matrix that span the thickness of the film with low anneal times and low defect densities, all with high reproducibility, where the latter is paramount. Through the use of our computer-controlled, pneumatically-actuated, purpose-built solvent vapor annealing chamber, we have the ability to monitor and control vapor pressure, solvent concentration within the film, and solvent evaporation rate with unprecedented precision and reliability. Focusing on evaporation, we report on two previously unexplored areas, chamber pressure during solvent evaporation and the flow rate of purging gas aiding the evaporation. We will report our exhaustive results following atomic force microscopy analysis of films exposed to a wide range of pressures and flow rates. Reliably achieving well-ordered films, while occurring within a large section of this parameter space, was correlated with high-flow evaporation rates and low chamber pressures. These results have significant implications on other methods of solvent annealing, including ``jar'' techniques.

Laser paper cleaning: the method of cleaning historical books

Science.gov (United States)

Zekou, Evangelini; Tsilikas, Ioannis; Chatzitheodoridis, Elias; Serafetinides, Alexander A.

2016-01-01

Conservation of cultural heritage treasures is the most important issue for transferring knowledge to the public through the next generation of students, academics, and researchers. Although this century is authenticating e-books and information by means of electronic text, still historical manuscripts as content as well as objects are the main original recourses of keeping a record of this transformation. The current work focuses on cleaning paper samples by the application of pulsed light, which is interventional. Experiments carried out using paper samples that are artificially colonized with Ulocladium chartarum. Paper is treated by Nd:YAG laser light. The available wavelength is 1064 nm, at various fluences, repetition rates and number of pulses. Two types of paper are stained with fungi colonies, which grow on substrates of clean paper, as well as on paper with ink text. The first type of paper is Whatman No.1056, which is closer to pure cellulose. The second type of paper is a page of a cultural heritage book published in 1926. Cleaning is performed using laser irradiation, thus defining the damage threshold of each sample. The treatment on paper Watman showed a yellowing, especially on areas with high concentration of fungi. The second sample was more durable to the exposure, performing the best results at higher fluences. Eventually, the paper samples are characterized, with optical microscopy and SEM/EDX analyses, prior to and after cleaning.

Summary report of the Banff clean energy dialogue : towards a truly Canadian clean energy strategy

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

A clean energy strategy will allow Canada to seize opportunities for prosperity in a low-carbon future, while also contributing to the country's economic growth. This report outlined the conclusions drawn by representatives of major energy corporations and policy-makers who gathered to discuss Canada's clean energy plans for the future. Attendants at the meeting concluded that energy conservation and energy efficiency will play a prominent role in a successful clean energy strategy. However, a price on carbon is needed to emphasize the fundamental relationship between energy and the environment. A successful strategy will feature the following 4 overarching principles: (1) economic opportunity, (2) social responsibility, (3) environmental stewardship, and (4) international strategy in relation to trade and development of new markets. The role that federal, provincial and municipal governments will play in developing and implementing the strategy was also presented. The meeting was divided into the following 6 working sessions: (1) global context for a clean energy strategy, (2) why a Canadian clean energy strategy? Why now?, (3) key pillars of a Canadian clean energy strategy, (4) key building blocks of a national clean energy strategy, (5) a balanced Canadian framework, and (6) next steps. 1 fig.

Tensile Properties and Integrity of Clean Room and Low-Modulus Disposable Nitrile Gloves: A Comparison of Two Dissimilar Glove Types

Science.gov (United States)

Phalen, Robert N.; Wong, Weng kee

2012-01-01

Background: The selection of disposable nitrile exam gloves is complicated by (i) the availability of several types or formulations, (ii) product variability, and (iii) an inability of common quality control tests to detect small holes in the fingers. Differences in polymer formulation (e.g. filler and plasticizer/oil content) and tensile properties are expected to account for much of the observed variability in performance. Objectives: This study evaluated the tensile properties and integrity (leak failure rates) of two glove choices assumed to contain different amounts of plasticizers/oils. The primary aims were to determine if the tensile properties and integrity differed and if associations existed among these factors. Additional physical and chemical properties were evaluated. Methods: Six clean room and five low-modulus products were evaluated using the American Society for Testing and Materials Method D412 and a modified water-leak test to detect holes capable of passing a virus or chemical agent. Results: Significant differences in the leak failure rates and tensile properties existed between the two glove types (P ≤ 0.05). The clean room gloves were about three times more likely to have leak failures (chi-square; P = 0.001). No correlation was observed between leak failures and tensile properties. Solvent extract, an indication of added plasticizer/oil, was not associated with leak failures. However, gloves with a maximum modulus gloves were a better choice for protection against aqueous chemical or biological penetration. The observed variability between glove products indicated that glove selection cannot rely solely on glove type or manufacturer labeling. Measures of modulus and AD may aid in the selection process, in contrast with common measures of tensile strength and elongation at break. PMID:22201179

On linear correlation between interfacial tension of water-solvent interface solubility of water in organic solvents and parameters of diluent effect scale

International Nuclear Information System (INIS)

Mezhov, Eh.A.; Khananashvili, N.L.; Shmidt, V.S.

1988-01-01

Presence of linear correlation between water solubility in nonmiscible with it organic solvents, interfacial tension of water-solvent interface, on the one hand, and solvent effect scale parameters and these solvents π* - on the other hand, is established. It allows, using certain tabular parameters of solvent effect or each solvent π*, to predict values of interfacial tension and water solubility for corresponding systems. It is shown, that solvent effect scale allows to predict values more accurately, than other known solvent scales, as it in contrast to other scales characterizes solvents, which are in equilibrium with water

Photophysics of Curcumin excited state in toluene-polar solvent mixtures: Role of H-bonding properties of the polar solvent

Energy Technology Data Exchange (ETDEWEB)

Saini, R.K.; Das, K., E-mail: kaustuv@rrcat.gov.in

2014-01-15

Excited state dynamics of Curcumin in binary solvent mixtures of toluene and polar H-bonding solvents were compared by using an instrument endowed with 40 ps time resolution. The solvation time constant of Curcumin increases significantly (and can therefore be measured) in polar solvents which have, either, both H-bond donating and accepting ability, or, only H-bond donating ability. These results suggest that the rate limiting step in the excited state dynamics of the pigment might be the formation and reorganization of the intermolecular H-bonding between the keto group of the pigment and the H-bond donating moieties of the polar solvent. -- Highlights: • Excited state dynamics of Curcumin in a binary solvent mixture of toluene and three polar H-bonding solvents were compared. • The solvation time constant increases significantly with polar solvents having, H-bond donating and accepting, or, H-bond donating ability. • Observed results suggest that H-bonding property of polar solvent plays an important role in the excited state dynamics. • Intermolecular H-bonding between the keto group of the pigment and polar solvent may be the rate limiting step.

Photophysics of Curcumin excited state in toluene-polar solvent mixtures: Role of H-bonding properties of the polar solvent

International Nuclear Information System (INIS)

Saini, R.K.; Das, K.

2014-01-01

Excited state dynamics of Curcumin in binary solvent mixtures of toluene and polar H-bonding solvents were compared by using an instrument endowed with 40 ps time resolution. The solvation time constant of Curcumin increases significantly (and can therefore be measured) in polar solvents which have, either, both H-bond donating and accepting ability, or, only H-bond donating ability. These results suggest that the rate limiting step in the excited state dynamics of the pigment might be the formation and reorganization of the intermolecular H-bonding between the keto group of the pigment and the H-bond donating moieties of the polar solvent. -- Highlights: • Excited state dynamics of Curcumin in a binary solvent mixture of toluene and three polar H-bonding solvents were compared. • The solvation time constant increases significantly with polar solvents having, H-bond donating and accepting, or, H-bond donating ability. • Observed results suggest that H-bonding property of polar solvent plays an important role in the excited state dynamics. • Intermolecular H-bonding between the keto group of the pigment and polar solvent may be the rate limiting step

Clinical and metabolic features of type 2 diabetes mellitus in participants of Chernobyl accident clean-up

International Nuclear Information System (INIS)

Zujeva, N.O.; Kovalenko, O.M.; Jefyimov, A.S.

2000-01-01

The clinical and metabolic features of type 2 diabetes mellitus (DM) in the participants of Chernobyl accident clean-up (PCAC) was studied. It was found out that DM in PCAC was first diagnosed against a background of formed cardiovascular pathology and hyper coagulation

Linear correlation of interfacial tension at water-solvent interface, solubility of water in organic solvents, and SE* scale parameters

International Nuclear Information System (INIS)

Mezhov, E.A.; Khananashvili, N.L.; Shmidt, V.S.

1988-01-01

A linear correlation has been established between the solubility of water in water-immiscible organic solvents and the interfacial tension at the water-solvent interface on the one hand and the parameters of the SE* and π* scales for these solvents on the other hand. This allows us, using the known tabulated SE* or π* parameters for each solvent, to predict the values of the interfacial tension and the solubility of water for the corresponding systems. We have shown that the SE* scale allows us to predict these values more accurately than other known solvent scales, since in contrast to other scales it characterizes solvents found in equilibrium with water

Comparative SEM analysis of nine F22 aligner cleaning strategies

Directory of Open Access Journals (Sweden)

Luca Lombardo

2017-09-01

Full Text Available Abstract Background The orthodontics industry has paid great attention to the aesthetics of orthodontic appliances, seeking to make them as invisible as possible. There are several advantages to clear aligner systems, including aesthetics, comfort, chairside time reduction, and the fact that they can be removed for meals and oral hygiene procedures. Methods Five patients were each given a series of F22 aligners, each to be worn for 14 days and nights, with the exception of meal and brushing times. Patients were instructed to clean each aligner using a prescribed strategy, and sections of the used aligners were observed under SEM. One grey-scale SEM image was saved per aligner in JPEG format with an 8-bit colour depth, and a total of 45 measurements on the grey scale (“Value” variable were made. This dataset was analysed statistically via repeated measures ANOVA to determine the effect of each of the nine cleaning strategies in each of the five patients. Results A statistically significant difference in the efficacy of the cleaning strategies was detected. Specifically, rinsing with water alone was significantly less efficacious, and a combination of cationic detergent solution and ultrasonication was significantly more efficacious than the other methods (p < 0.05. Conclusions Of the nine cleaning strategies examined, only that involving 5 min of ultrasonication at 42 k Hz combined with a 0.3% germicidal cationic detergent was observed to be statistically effective at removing the bacterial biofilm from the surface of F22 aligners.

Analysis of recovered solvents from coal liquefaction in a flowing-solvent reactor by SEC and UV-fluorescence

Energy Technology Data Exchange (ETDEWEB)

Li, W.Y.; Feng, J.; Xie, K.C.; Kandiyoti, R. [Taiyuan University of Technology, Taiyuan (China)

2005-08-01

Point of Ayr coal has been extracted using three solvents: tetralin, quinoline and 1-methyl-2-pyrrolidinone (NMP); at two temperatures: 350 {sup o}C and 450{sup o}C, corresponding approximately to before and after the onset of massive covalent bond scission by pyrolysis. These solvents differ in solvent power and the ability to donate hydrogen atoms to stabilize free radicals produced by pyrolysis of the coal. Analysis of the fresh solvents and recovered solvents from coal liquefaction was achieved by size exclusion chromatography and UV-fluorescence spectroscopy. In the blank run, it was testified that the filling material sand and the steel powder did not react with solvent with increasing reaction temperature. The role of hydrogen donation in the tetralin extracts was to increase the proportion of large molecules with increasing extraction temperature. Quinoline and NMP both have the powerful extracting capability to get more materials out of coal with increasing extraction temperature.

Analysis of recovered solvents from coal liquefaction in a flowing-solvent reactor by SEC and UV-fluorescence

Energy Technology Data Exchange (ETDEWEB)

Wen-Ying Li; Jie Feng; Ke-Chang Xie; R. Kandiyoti [Taiyuan University of Technology, Taiyuan (China). Key Laboratory of Coal Science and Technology for Ministry of Education and Shanxi Province

2005-08-01

Point of Ayr coal has been extracted using three solvents: tetralin, quinoline and 1-methyl-2-pyrrolidinone (NMP); at two temperatures: 350{sup o}C and 450{sup o}C, corresponding approximately to before and after the onset of massive covalent bond scission by pyrolysis. These solvents differ in solvent power and the ability to donate hydrogen atoms to stabilize free radicals produced by pyrolysis of the coal. Analysis of the fresh solvents and recovered solvents from coal liquefaction was achieved by size exclusion chromatography and UV-fluorescence spectroscopy. In the blank run, it was testified that the filling material sand and the steel powder did not react with solvent with increasing reaction temperature. The role of hydrogen donation in the tetralin extracts was to increase the proportion of large molecules with increasing extraction temperature. Quinoline and NMP both have the powerful extracting capability to get more materials out of coal with increasing extraction temperature.

The Clean Energy Manufacturing Analysis Center (CEMAC): Providing Analysis and Insights on Clean Technology Manufacturing

Energy Technology Data Exchange (ETDEWEB)

Johnson, Nicholi S [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-09-28

The U.S. Department of Energy's Clean Energy Manufacturing Analysis Center (CEMAC) provides objective analysis and up-to-date data on global supply chains and manufacturing of clean energy technologies. Policymakers and industry leaders seek CEMAC insights to inform choices to promote economic growth and the transition to a clean energy economy.

An absorbing microwave micro-solid-phase extraction device used in non-polar solvent microwave-assisted extraction for the determination of organophosphorus pesticides.

Science.gov (United States)

Wang, Ziming; Zhao, Xin; Xu, Xu; Wu, Lijie; Su, Rui; Zhao, Yajing; Jiang, Chengfei; Zhang, Hanqi; Ma, Qiang; Lu, Chunmei; Dong, Deming

2013-01-14

A single-step extraction-cleanup method, including microwave-assisted extraction (MAE) and micro-solid-phase extraction (μ-SPE), was developed for the extraction of ten organophosphorus pesticides in vegetable and fruit samples. Without adding any polar solvent, only one kind of non-polar solvent (hexane) was used as extraction solvent in the whole extraction step. Absorbing microwave μ-SPE device, was prepared by packing activated carbon with microporous polypropylene membrane envelope, and used as not only the sorbent in μ-SPE, but also the microwave absorption medium. Some experimental parameters effecting on extraction efficiency was investigated and optimized. 1.0 g of sample, 8 mL of hexane and three absorbing microwave μ-SPE devices were added in the microwave extraction vessel, the extraction was carried out under 400 W irradiation power at 60°C for 10 min. The extracts obtained by MAE-μ-SPE were directly analyzed by GC-MS without any clean-up process. The recoveries were in the range of 93.5-104.6%, and the relative standard deviations were lower than 8.7%. Copyright © 2012 Elsevier B.V. All rights reserved.

Organic solvent topical report

International Nuclear Information System (INIS)

COWLEY, W.L.

1999-01-01

This report provides the basis for closing the organic solvent safety issue. Sufficient information is presented to conclude that risk posed by an organic solvent fire is within risk evaluation guidelines. This report updates information contained in Analysis of Consequences of Postulated Solvent Fires in Hanford Site Waste Tanks. WHC-SD-WM-CN-032. Rev. 0A (Cowley et al. 1996). However, this document will not replace Cowley et al (1996) as the primary reference for the Basis for Interim Operation (BIO) until the recently submitted BIO amendment (Hanson 1999) is approved by the US Department of Energy. This conclusion depends on the use of controls for preventing vehicle fuel fires and for limiting the use of flame cutting in areas where hot metal can fall on the waste surface.The required controls are given in the Tank Waste Remediation System Technical Safety Requirements (Noorani 1997b). This is a significant change from the conclusions presented in Revision 0 of this report. Revision 0 of this calcnote concluded that some organic solvent fire scenarios exceeded risk evaluation guidelines, even with controls imposed

Organic solvent topical report

Energy Technology Data Exchange (ETDEWEB)

COWLEY, W.L.

1999-05-13

This report provides the basis for closing the organic solvent safety issue. Sufficient information is presented to conclude that risk posed by an organic solvent fire is within risk evaluation guidelines. This report updates information contained in Analysis of Consequences of Postulated Solvent Fires in Hanford Site Waste Tanks. WHC-SD-WM-CN-032. Rev. 0A (Cowley et al. 1996). However, this document will not replace Cowley et al (1996) as the primary reference for the Basis for Interim Operation (BIO) until the recently submitted BIO amendment (Hanson 1999) is approved by the US Department of Energy. This conclusion depends on the use of controls for preventing vehicle fuel fires and for limiting the use of flame cutting in areas where hot metal can fall on the waste surface.The required controls are given in the Tank Waste Remediation System Technical Safety Requirements (Noorani 1997b). This is a significant change from the conclusions presented in Revision 0 of this report. Revision 0 of this calcnote concluded that some organic solvent fire scenarios exceeded risk evaluation guidelines, even with controls imposed.

Modeling coding-sequence evolution within the context of residue solvent accessibility

Directory of Open Access Journals (Sweden)

Scherrer Michael P

2012-09-01

Full Text Available Abstract Background Protein structure mediates site-specific patterns of sequence divergence. In particular, residues in the core of a protein (solvent-inaccessible residues tend to be more evolutionarily conserved than residues on the surface (solvent-accessible residues. Results Here, we present a model of sequence evolution that explicitly accounts for the relative solvent accessibility of each residue in a protein. Our model is a variant of the Goldman-Yang 1994 (GY94 model in which all model parameters can be functions of the relative solvent accessibility (RSA of a residue. We apply this model to a data set comprised of nearly 600 yeast genes, and find that an evolutionary-rate ratio ω that varies linearly with RSA provides a better model fit than an RSA-independent ω or an ω that is estimated separately in individual RSA bins. We further show that the branch length t and the transition-transverion ratio κ also vary with RSA. The RSA-dependent GY94 model performs better than an RSA-dependent Muse-Gaut 1994 (MG94 model in which the synonymous and non-synonymous rates individually are linear functions of RSA. Finally, protein core size affects the slope of the linear relationship between ω and RSA, and gene expression level affects both the intercept and the slope. Conclusions Structure-aware models of sequence evolution provide a significantly better fit than traditional models that neglect structure. The linear relationship between ω and RSA implies that genes are better characterized by their ω slope and intercept than by just their mean ω.

Genesis Solar Wind Sample 61422: Experiment in Variation of Sequence of Cleaning Solvent for Removing Carbon-Bearing Contamination

Science.gov (United States)

Allton, J. H.; Kuhlman, K. R.; Allums, K. K.; Gonzalez, C. P.; Jurewicz, A. J. G.; Burnett, D. S.; Woolum, D. S.

2015-01-01

The recovered Genesis collector fragments are heavily contaminated with crash-derived particulate debris. However, megasonic treatment with ultra-pure-water (UPW; resistivity (is) greater than18 meg-ohm-cm) removes essentially all particulate contamination greater than 5 microns in size [e.g.1] and is thus of considerable importance. Optical imaging of Si sample 60336 revealed the presence of a large C-rich particle after UPW treatment that was not present prior to UPW. Such handling contamination is occasionally observed, but such contaminants are normally easily removed by UPW cleaning. The 60336 particle was exceptional in that, surprisingly, it was not removed by additional UPW or by hot xylene or by aqua regia treatment. It was eventually removed by treatment with NH3-H2O2. Our best interpretation of the origin of the 60336 particle was that it was adhesive from the Post-It notes used to stabilize samples for transport from Utah after the hard landing. It is possible that the insoluble nature of the 60336 particle comes from interaction of the Post-It adhesive with UPW. An occasional bit of Post-It adhesive is not a major concern, but C particulate contamination also occurs from the heat shield of the Sample Return Capsule (SRC) and this is mixed with inorganic contamination from the SRC and the Utah landing site. If UPW exposure also produced an insoluble residue from SRC C, this would be a major problem in chemical treatments to produce clean surfaces for analysis. This paper reports experiments to test whether particulate contamination was removed more easily if UPW treatment was not used.

"Cleaning" the Surface of Hydroxyapatite Nanorods by a Reaction-Dissolution Approach.

Science.gov (United States)

Cao, Binrui; Yang, Mingying; Wang, Lin; Xu, Hong; Zhu, Ye; Mao, Chuanbin

2015-10-21

Synthetic nanoparticles are always terminated with coating molecules, which are often cytotoxic and not desired in biomedicine. Here we propose a novel reaction-dissolution approach to remove the cytotoxic coating molecules. A two-component solution is added to the nanoparticle solution; one component reacts with the coating molecules to form a salt whereas another is a solvent for dissolving and thus removing the salt. As a proof of concept, this work uses a NaOH-ethanol solution to remove the cytotoxic linoleic acid molecules coated on the hydroxyapatite nanorods (HAP-NRs). The removal of the coating molecules not only significantly improves the biocompatibility of HAP-NRs but also enables their oriented attachment into tightly-bound superstructures, which mimic the organized HAP crystals in bone and enamel and can promote the osteogenic differentiation of mesenchymal stem cells. Our reaction-dissolution approach can be extended to the surface "cleaning" of other nanomaterials.

Is the Clean Development Mechanism Effective for Emission Reductions?

DEFF Research Database (Denmark)

Tarp, Finn; Huang, Yongfu; He, Jingjing

2014-01-01

with great challenges, given the wide divide between developed and developing nations. Against this background, comprehensive evaluations of the effectiveness of Kyoto market‐based mechanisms such as the Clean Development Mechanism (CDM) in terms of mitigating human‐induced climate change are urgently needed...... reductions for 60 CDM host countries over the period 2005–2010, using a newly developed econometric method for dynamic panel data models associated with the X‐differencing procedure. Our results provide evidence in support of a decline in CO 2 emissions in CDM host countries. We conclude...

National Clean Fleets Partnership (Fact Sheet)

Energy Technology Data Exchange (ETDEWEB)

2012-01-01

Provides an overview of Clean Cities National Clean Fleets Partnership (NCFP). The NCFP is open to large private-sector companies that have fleet operations in multiple states. Companies that join the partnership receive customized assistance to reduce petroleum use through increased efficiency and use of alternative fuels. This initiative provides fleets with specialized resources, expertise, and support to successfully incorporate alternative fuels and fuel-saving measures into their operations. The National Clean Fleets Partnership builds on the established success of DOE's Clean Cities program, which reduces petroleum consumption at the community level through a nationwide network of coalitions that work with local stakeholders. Developed with input from fleet managers, industry representatives, and Clean Cities coordinators, the National Clean Fleets Partnership goes one step further by working with large private-sector fleets.

Implicit solvent simulations of DNA and DNA-protein complexes: Agreement with explicit solvent vs experiment

Czech Academy of Sciences Publication Activity Database

Chocholoušová, Jana; Feig, M.

2006-01-01

Roč. 110, č. 34 (2006), s. 17240-17251 ISSN 1520-6106 Keywords : implicit solvent * explicit solvent * protein DNA complex Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.115, year: 2006

Biomolecular-solvent stereodynamic coupling probed by deuteration

International Nuclear Information System (INIS)

Fornili, S.L.; Leone, M.; Madonia, F.; Migliore, M.; Palma-Vittorelli, M.B.; Palma, M.U.; San Biagio, P.L.

1983-01-01

Thermodynamic interpretation of experiments with isotopically perturbed solvent supports the view that solvent stereodynamics is directly relevant to thermodynamic stability of biomolecules. According with the current understanding of the structure of the aqueous solvent, in any stereodynamic configuration of the latter, connectivity pathways are identifiable for their topologic and order properties. Perturbing the solvent by isotopic substitution or, e.g., by addition of co-solvents, can therefore be viewed as reinforcing or otherwise perturbing these topologic structures. This microscopic model readily visualizes thermodynamic interpretation. In conclusion, the topologic stereodynamic structures of connectivity pathways in the solvent, as modified by interaction with solutes, acquire a specific thermodynamic and biological significance, and the problem of thermodynamic and functional stability of biomolecules is seen in its full pertinent phase space

Surface cleaning and preparation in AlGaN/GaN-based HEMT processing as assessed by X-ray photoelectron spectroscopy

International Nuclear Information System (INIS)

Gonzalez-Posada, Fernando; Bardwell, Jennifer A.; Moisa, Simona; Haffouz, Soufien; Tang, Haipeng; Brana, Alejandro F.; Munoz, Elias

2007-01-01

The chemical composition of the AlGaN/GaN surface during typical process steps in transistor fabrication was studied using X-ray photoelectron spectroscopy (XPS). The steps studied included organic solvent cleaning, 1:1 HCl:H 2 O dip, buffered oxide etch dip, oxygen plasma descum and rapid thermal annealing (RTA). The surface composition was calculated after correction for the interference of the Ga Auger lines in the N 1s portion of the spectra. The buffered oxide etched (BOE) surface showed a greater tendency for Al (compared to Ga) to be oxidized in the surface, under a layer of adventitious carbon. Three different treatments were found to yield a combination of low C and O levels in the surface. Both plasma cleaning and RTA were highly effective at reducing the carbon contamination of the surface, but did increase the oxygen levels. The RTA treated surface was found to have low levels of oxygen incorporation to a depth of 2-6 nm

Heat exchanger cleaning

International Nuclear Information System (INIS)

Gatewood, J.R.

1980-01-01

A survey covers the various types of heat-exchange equipment that is cleaned routinely in fossil-fired generating plants, the hydrocarbon-processing industry, pulp and paper mills, and other industries; the various types, sources, and adverse effects of deposits in heat-exchange equipment; some details of the actual procedures for high-pressure water jetting and chemical cleaning of some specific pieces of equipment, including nuclear steam generators. (DN)

Structural transition of a homopolymer in solvents mixture

International Nuclear Information System (INIS)

Guettari, Moez; Aschi, Adel; Gomati, Riadh; Gharbi, Abdelhafidh

2008-01-01

The present work is aimed at studying the thermodynamic behaviour of a polymer in solvents mixture. Dynamic light scattering is used to measure the hydrodynamic radius of polyvinylpyrrolidone (M w = 360,000 g/mol), in water/methanol solvents mixture, versus the mixed solvents composition at 25 deg. C. Then, we show that the polymer conformation adopts the Coil-Globule-Coil structure when the methanol molar fraction X A is varied. This transition is attributed to solvent quality change which result from water and methanol complex formation. The polymer contraction rate calculated for each composition takes its maximum value at X A = 0.17. Hildebrand theory assuming the solvents mixture as an equivalent solvent was used to analyze the change in mixed solvents quality. These changes can be attributed to dispersive forces in solvents mixture

Effect of solvent polarity and temperature on the spectral and thermodynamic properties of exciplexes of 1-cyanonaphthalene with hexamethylbenzene in organic solvents

International Nuclear Information System (INIS)

Asim, Sadia; Mansha, Asim; Grampp, Günter; Landgraf, Stephan; Zahid, Muhammad; Bhatti, Ijaz Ahmad

2014-01-01

Study of the effect of solvent polarity and temperature is done on the exciplex emission spectra of 1-cyanonaphthalene with hexamethylbenzene. Exciplex system is studied in the range of partially polar solvents and in solvent mixture of propyl acetate and butyronitrile. The unique feature of this solvent mixture is that only the solvent polarity changes (6.0≤ε s ≤24.7) with the change in the mole fraction of solvents whereas the solvent viscosity and refractive index remains unaffected. Thermodynamic properties are calculated according to the models developed by Weller and Kuzmin. Fluorescence lifetimes for both the fluorophore as well as the exciplex are evaluated in all used solvents. Exciplex energetics as a function of solvent polarity and temperature are also discussed. Kuzmin model of self-consistent polarization is used for the explanation of the exciplex emission spectra. The effects of solvent polarity and temperature on energy of zero–zero transitions (hv 0 / ), Huang–Rhys factor (S), Gauss broadening of vibronic level (σ) and the dominant high-frequency vibration (hν ν ) are investigated. The strong dependence of exciplex stability and energetics upon the solvent polarity and temperature are observed. Full charge transfer exciplexes were observed in solvents of all polarities and stronger exciplex with large emission intensities were found in solvents of low polarities but with the increase in solvent polarity the exciplex becomes weak and they dissociate fastly into radical ion pairs. The kinetic model of Kuzmin was observed to reduce into the Weller kinetic model for this exciplex system with ∆G ET = −0.22 eV and the spectral shift, h∆ν>0.2 eV. - Highlights: • Exciplex formed as a result of mixing of charge transfer and locally excited states. • Effect of solvents polarity and temperature on the exciplex stability and thermodynamics. • Solvent polarity will decide the formation of contact radical ion pair or solvent separated

Air cleaning using regenerative silica gel wheel

DEFF Research Database (Denmark)

Fang, Lei

2011-01-01

This paper discussed the necessity of indoor air cleaning and the state of the art information on gas-phase air cleaning technology. The performance and problems of oxidation and sorption air cleaning technology were summarized and analysed based on the literature studies. Eventually, based...... on an experimental study, a technology called clean air heat pump is proposed as a practical approach for indoor air cleaning....

Green Cleaning Label Power

Science.gov (United States)

Balek, Bill

2012-01-01

Green cleaning plays a significant and supportive role in helping education institutions meet their sustainability goals. However, identifying cleaning products, supplies and equipment that truly are environmentally preferable can be daunting. The marketplace is inundated with products and services purporting to be "green" or environmentally…

Gas turbine cleaning upgrade (compressor wash)

Energy Technology Data Exchange (ETDEWEB)

Asplund, P [Gas Turbine Efficiency, Jarfalla (Sweden)

1999-12-31

The influence of gas turbine degradation on operating costs is high. Gas turbine cleaning is one of many actions taken for power recovery and is to consider as preventive maintenance. It is generally performed within the industrial field and occasionally within the aero sector. In order to meet the gas turbine development win high blade loads and ever-increasing temperatures, together with emission Aces and environmental regulations, more efficient and careful cleaning methods are needed. Following a survey about potentials for cost reduction in gas turbine operation a new man-hour and water saving cleaning method has been evaluated for a standard process. Compared with traditional cleaning methods, the new method is water,- cost,- weight and space saving due to a new washing technique. Traditional methods are based on using different nozzles for ON and OFF-line cleaning, which rise the demand for complicated systems. In the new method the same nozzle installation, same liquid flow and pressure is used for both ON and OFF-line cleaning. This gives a cost reduction of appr. 20.000 - 30.000 USD per gas turbine depending on installation and size. Evaluation of the new method shows significantly improved ON -line cleaning performance and thus OFF -line cleaning is required only during scheduled stops. (orig.) 10 refs.

Gas turbine cleaning upgrade (compressor wash)

Energy Technology Data Exchange (ETDEWEB)

Asplund, P. [Gas Turbine Efficiency, Jarfalla (Sweden)

1998-12-31

The influence of gas turbine degradation on operating costs is high. Gas turbine cleaning is one of many actions taken for power recovery and is to consider as preventive maintenance. It is generally performed within the industrial field and occasionally within the aero sector. In order to meet the gas turbine development win high blade loads and ever-increasing temperatures, together with emission Aces and environmental regulations, more efficient and careful cleaning methods are needed. Following a survey about potentials for cost reduction in gas turbine operation a new man-hour and water saving cleaning method has been evaluated for a standard process. Compared with traditional cleaning methods, the new method is water,- cost,- weight and space saving due to a new washing technique. Traditional methods are based on using different nozzles for ON and OFF-line cleaning, which rise the demand for complicated systems. In the new method the same nozzle installation, same liquid flow and pressure is used for both ON and OFF-line cleaning. This gives a cost reduction of appr. 20.000 - 30.000 USD per gas turbine depending on installation and size. Evaluation of the new method shows significantly improved ON -line cleaning performance and thus OFF -line cleaning is required only during scheduled stops. (orig.) 10 refs.

Aminosilicone solvent recovery methods and systems

Science.gov (United States)

Spiry, Irina Pavlovna; Perry, Robert James; Wood, Benjamin Rue; Singh, Surinder Prabhjot; Farnum, Rachel Lizabeth; Genovese, Sarah Elizabeth

2018-02-13

The present invention is directed to aminosilicone solvent recovery methods and systems. The methods and systems disclosed herein may be used to recover aminosilicone solvent from a carbon dioxide containing vapor stream, for example, a vapor stream that leaves an aminosilicone solvent desorber apparatus. The methods and systems of the invention utilize a first condensation process at a temperature from about 80.degree. C. to about 150.degree. C. and a second condensation process at a temperature from about 5.degree. C. to about 75.degree. C. The first condensation process yields recovered aminosilicone solvent. The second condensation process yields water.

L-Reactor 186-basin cleaning alternatives

International Nuclear Information System (INIS)

Turcotte, M.D.S.

1983-01-01

Operation of L Reactor will necessitate annual cleaning of the L Area 186 basins. Alternatives are presented for sediment discharge due to 186-basin cleaning activities as a basis for choosing the optimal cleaning method. Current cleaning activities (i.e. removal of accumulated sediments) for the P, C and K-Area 186 basins result in suspended solids concentrations in the effluent waters above the NPDES limits, requiring an exemption from the NPDES permit for these short-term releases. The objective of mitigating the 186-basin cleaning activities is to decrease the suspended solids concentrations to within permit limits while continuing satisfactory operation of the basins

Relevance of 1,2,5,6,9,10-hexabromocyclododecane diastereomer structure on partitioning properties, column-retention and clean-up procedures.

Science.gov (United States)

Mariussen, Espen; Haukås, Marianne; Arp, Hans Peter H; Goss, Kai-Uwe; Borgen, Anders; Sandanger, Torkjel M

2010-02-26

To optimize clean-up procedures for the analysis of alpha-, beta-, and gamma-hexabromocyclododecanes (HBCD) in environmental and biological extracts, their retention behavior on silica gel and florisil was investigated using diverse mobile-phase solvents and accounting for matrix effects. The beta-diastereomer, relative to the alpha- and gamma-diastereomers, is substantially retained on both florisil and silica gel regardless of the solvent used. The beta-diastereomer is therefore prone to undergo selective loss during clean-up. This sequence is counterintuitive to sequences based on reverse-phase chromatography with a C18-column, in which the alpha- (and not the beta-) isomer is eluted first when using a polar solvent. There has been some discrepancy regarding the structures of these diastereomers in the literature, with structures based on X-ray crystallography only becoming recently available. Based on these X-ray crystal structures, physical-chemical properties (the octanol-water partitioning constant, the Henry's law constant, subcooled liquid vapour pressures and subcooled liquid water solubilities) of the HBCD diastereomers were estimated using the quantum-chemistry based software COSMOtherm, and were found to differ from previously calculated values using different structures (e.g. log K(aw) for alpha-, beta-, and gamma-HBCD are here estimated to be -8.3, -9.3 and -8.2 respectively). Hypothesis relating differences in structure to physical-chemical properties and retention sequences are presented. The extra retention of the beta-diastereomer on silica gel and florisil is likely because it can form both greater specific (i.e. polar) and non-specific (i.e. non-polar) interactions with surfaces than the other diastereomers. Non-specific interactions can also account for the counter-intuitive elution orders with C(18)-reverse-phase chromatography. These results indicate that care should be taken when isolating HBCDs and other molecular diastereomers from

Work ability score of solvent-exposed workers.

Science.gov (United States)

Furu, Heidi; Sainio, Markku; Hyvärinen, Hanna-Kaisa; Kaukiainen, Ari

2018-03-28

Occupational chronic solvent encephalopathy (CSE), characterized by neurocognitive dysfunction, often leads to early retirement. However, only the more severe cases are diagnosed with CSE, and little is known about the work ability of solvent-exposed workers in general. The aim was to study memory and concentration symptoms, work ability and the effect of both solvent-related and non-occupational factors on work ability, in an actively working solvent-exposed population. A questionnaire on exposure and health was sent to 3640 workers in four solvent-exposed fields, i.e. painters and floor-layers, boat builders, printers, and metal workers. The total number of responses was 1730. We determined the work ability score (WAS), a single question item of the Work Ability Index, and studied solvent exposure, demographic factors, Euroquest memory and concentration symptoms, chronic diseases, and employment status using univariate and multivariate analyses. The findings were compared to those of a corresponding national blue-collar reference population (n = 221), and a small cohort of workers with CSE (n = 18). The proportion of workers with memory and concentration symptoms was significantly associated with solvent exposure. The WAS of solvent-exposed workers was lower than that of the national blue-collar reference group, and the difference was significant in the oldest age group (those aged over 60). Solvent-exposed worker's WAS were higher than those of workers diagnosed with CSE. The WAS were lowest among painters and floor-layers, followed by metal workers and printers, and highest among boat builders. The strongest explanatory factors for poor work ability were the number of chronic diseases, age and employment status. Solvent exposure was a weak independent risk factor for reduced WAS, comparable to a level of high alcohol consumption. Even if memory and concentration symptoms were associated with higher solvent exposure, the effect of solvents on self

Effectiveness of various cleaning and disinfectant products on Clostridium difficile spores of PCR ribotypes 010, 014 and 027

NARCIS (Netherlands)

Kenters, N.; E. Huijskens (Elisabeth); de Wit, S.C.J.; Sanders, I.G.J.M.; J.M. van Rosmalen (Joost); E. Kuijper; Voss, A.

2017-01-01

textabstractBackground: In healthcare facilities, Clostridium difficile infections spread by transmission of bacterial spores. Appropriate sporicidal disinfectants are needed to prevent development of clusters and outbreaks. In this study different cleaning/disinfecting wipes and sprays were tested

Recent Advances in Anhydrous Solvents for CO2 Capture: Ionic Liquids, Switchable Solvents, and Nanoparticle Organic Hybrid Materials

International Nuclear Information System (INIS)

Park, Youngjune; Lin, Kun-Yi Andrew; Park, Ah-Hyung Alissa; Petit, Camille

2015-01-01

CO 2 capture by amine scrubbing, which has a high CO 2 capture capacity and a rapid reaction rate, is the most employed and investigated approach to date. There are a number of recent large-scale demonstrations including the Boundary Dam Carbon Capture Project by SaskPower in Canada that have reported successful implementations of aqueous amine solvent in CO 2 capture from flue gases. The findings from these demonstrations will significantly advance the field of CO 2 capture in the coming years. While the latest efforts in aqueous amine solvents are exciting and promising, there are still several drawbacks to amine-based CO 2 capture solvents including high volatility and corrosiveness of the amine solutions as well as the high parasitic energy penalty during the solvent regeneration step. Thus, in a parallel effort, alternative CO 2 capture solvents, which are often anhydrous, have been developed as the third-generation CO 2 capture solvents. These novel classes of liquid materials include ionic liquids, CO 2 -triggered switchable solvents (i.e., CO 2 -binding organic liquids, reversible ionic liquids), and nanoparticle organic hybrid materials. This paper provides a review of these various anhydrous solvents and their potential for CO 2 capture. Particular attention is given to the mechanisms of CO 2 absorption in these solvents, their regeneration and their processability – especially taking into account their viscosity. While not intended to provide a complete coverage of the existing literature, this review aims at pointing the major findings reported for these new classes of CO 2 capture media.

Clean room actuators

Energy Technology Data Exchange (ETDEWEB)

Higuchi, Toshiro

1987-06-01

This report explains on the present status of the clean room actuators including the author's research results. In a clean room, there exists a possibility of dust generation, even when a direct human work is eliminated by the use of robots or automatic machines, from the machines themselves. For this, it is important to develop such clean robots and transfer/positioning mechanism that do not generate dusts, and to develop an actuator and its control technique. Topics described in the report are as follows: 1. Prevention of dust diffusion by means of sealing. 2. Elimination of mechanical contact (Linear induction motor and pneumatic float, linear motor and magnetic attraction float, linear motor and air bearing, and magnetic bearing). 3. Contactless actuator having a positioning mechanism (Use of linear step motor and rotary contactless actuator). (15 figs, 11 refs)

Evaluating exposure of pedestrians to airborne contaminants associated with non-potable water use for pavement cleaning.

Science.gov (United States)

Seidl, M; Da, G; Ausset, P; Haenn, S; Géhin, E; Moulin, L

2016-04-01

Climate change and increasing demography press local authorities to look after affordable water resources and replacement of drinking water for city necessities like street and pavement cleaning by more available raw water. Though, the substitution of drinking by non-drinking resources demands the evaluation of sanitary hazards. This article aims therefore to evaluate the contribution of cleaning water to the overall exposure of city dwellers in case of wet pavement cleaning using crossed physical, chemical and biological approaches. The result of tracer experiments with fluorescein show that liquid water content of the cleaning aerosol produced is about 0.24 g m(-3), rending possible a fast estimation of exposure levels. In situ analysis of the aerosol particles indicates a significant increase in particle number concentration and particle diameter, though without change in particle composition. The conventional bacterial analysis using total coliforms as tracer suggests that an important part of the contamination is issued from the pavement. The qPCR results show a more than 20-fold increase of background genome concentration for Escherichia coli and 10-fold increase for Enterococcus but a negligible contribution of the cleaning water. The fluorescence analysis of the cleaning aerosol confirms the above findings identifying pavement surface as the major contributor to aerosol organic load. The physical, chemical and microbiological approaches used make it possible to describe accurately the cleaning bioaerosol and to identify the existence of significantly higher levels of all parameters studied during the wet pavement cleaning. Though, the low level of contamination and the very short time of passage of pedestrian in the zone do not suggest a significant risk for the city dwellers. As the cleaning workers remain much longer in the impacted area, more attention should be paid to their chronic exposure.

Structural transition of a homopolymer in solvents mixture

Energy Technology Data Exchange (ETDEWEB)

Guettari, Moez [Laboratoire de Physique de la Matiere Molle, Faculte des Sciences de Tunis, Campus Universitaire, 2092 Tunisia (Tunisia)], E-mail: gtarimoez@yahoo.fr; Aschi, Adel; Gomati, Riadh; Gharbi, Abdelhafidh [Laboratoire de Physique de la Matiere Molle, Faculte des Sciences de Tunis, Campus Universitaire, 2092 Tunisia (Tunisia)

2008-07-01

The present work is aimed at studying the thermodynamic behaviour of a polymer in solvents mixture. Dynamic light scattering is used to measure the hydrodynamic radius of polyvinylpyrrolidone (M{sub w} = 360,000 g/mol), in water/methanol solvents mixture, versus the mixed solvents composition at 25 deg. C. Then, we show that the polymer conformation adopts the Coil-Globule-Coil structure when the methanol molar fraction X{sub A} is varied. This transition is attributed to solvent quality change which result from water and methanol complex formation. The polymer contraction rate calculated for each composition takes its maximum value at X{sub A} = 0.17. Hildebrand theory assuming the solvents mixture as an equivalent solvent was used to analyze the change in mixed solvents quality. These changes can be attributed to dispersive forces in solvents mixture.

40 CFR 63.744 - Standards: Cleaning operations.

Science.gov (United States)

2010-07-01

... system with equivalent emission control. (e) Exempt cleaning operations. The following cleaning...) Cleaning of aircraft and ground support equipment fluid systems that are exposed to the fluid, including... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Standards: Cleaning operations. 63.744...

Quantitation of buried contamination by use of solvents. [degradation of silicone polymers by amine solvents

Science.gov (United States)

Pappas, S. P.; Hsiao, Y. C.; Hill, L. W.

1973-01-01

Spore recovery form cured silicone potting compounds using amine solvents to degrade the cured polymers was investigated. A complete list of solvents and a description of the effect of each on two different silicone polymers is provided.

Significant OH production under surface cleaning and air cleaning conditions: Impact on indoor air quality.

Science.gov (United States)

Carslaw, N; Fletcher, L; Heard, D; Ingham, T; Walker, H

2017-11-01

We report measurements of hydroxyl (OH) and hydroperoxy (HO 2 ) radicals made by laser-induced fluorescence spectroscopy in a computer classroom (i) in the absence of indoor activities (ii) during desk cleaning with a limonene-containing cleaner (iii) during operation of a commercially available "air cleaning" device. In the unmanipulated environment, the one-minute averaged OH concentration remained close to or below the limit of detection (6.5×10 5  molecule cm -3 ), whilst that of HO 2 was 1.3×10 7  molecule cm -3 . These concentrations increased to ~4×10 6 and 4×10 8  molecule cm -3 , respectively during desk cleaning. During operation of the air cleaning device, OH and HO 2 concentrations reached ~2×10 7 and ~6×10 8  molecule cm -3 respectively. The potential of these OH concentrations to initiate chemical processing is explored using a detailed chemical model for indoor air (the INDCM). The model can reproduce the measured OH and HO 2 concentrations to within 50% and often within a few % and demonstrates that the resulting secondary chemistry varies with the cleaning activity. Whilst terpene reaction products dominate the product composition following surface cleaning, those from aromatics and other VOCs are much more important during the use of the air cleaning device. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Solvent-vapor-assisted imprint lithography

NARCIS (Netherlands)

Voicu, Nicoleta E.; Ludwigs, Sabine; Crossland, Edward J. W.; Andrew, Piers; Steiner, Ullrich

2007-01-01

Sub-micrometer features are replicated into high-molecular-weight polymer resists by using solvent-assisted nanoimprint lithography (see figure). By swelling the polymer in a controlled solvent-vapor atmosphere, millibar pressures and ambient temperatures are sufficient to achieve high-fidelity

To evaluate and compare the efficacy, cleaning ability of hand and two rotary systems in root canal retreatment.

Science.gov (United States)

Shivanand, Sunita; Patil, Chetan R; Thangala, Venugopal; Kumar, Pabbati Ravi; Sachdeva, Jyoti; Krishna, Akash

2013-05-01

To evaluate and compare the efficacy, cleaning ability of hand and two rotary systems in root canal retreatment. Sixty extracted premolars were retreated with following systems: Group -ProTaper Universal retreatment files, Group 2-ProFile system, Group 3-H-file. Specimens were split longitudinally and amount of remaining gutta-percha on the canal walls was assessed using direct visual scoring with the aid of stereomicroscope. Results were statistically analyzed using ANOVA test. Completely clean root canal walls were not achieved with any of the techniques investigated. However, all three systems proved to be effective for gutta-percha removal. Significant difference was found between ProTaper universal retreatment file and H-file, and also between ProFile and H-file. Under the conditions of the present study, ProTaper Universal retreatment files left significantly less guttapercha and sealer than ProFile and H-file. Rotary systems in combination with gutta-percha solvents can perform superiorly as compared to the time tested traditional hand instrumentation in root canal retreatment.

Effectiveness of various cleaning and disinfectant products on Clostridium difficile spores of PCR ribotypes 010, 014 and 027

NARCIS (Netherlands)

Kenters, N.; Huijskens, E.G.; Wit, S.C.J. de; Sanders, I.; Rosmalen, J. van; Kuijper, E.J.; Voss, A.

2017-01-01

BACKGROUND: In healthcare facilities, Clostridium difficile infections spread by transmission of bacterial spores. Appropriate sporicidal disinfectants are needed to prevent development of clusters and outbreaks. In this study different cleaning/disinfecting wipes and sprays were tested for their

Gas plant cleaning case history

Energy Technology Data Exchange (ETDEWEB)

Woods, B

1971-03-22

Basic steps to be taken before using any cleaning method are select a responsible group and give it full responsibility; know the problem, what type of fouling, lab samples, amount of material, time and cost; sell the idea to management; maintain the cleaning equipment; and follow up each cleaning operation. These principles have been applied to advantage in the amine contractor at Taylor, a vessel 60 ft high with 78-in. OD, containing carbon steel deck trays with stainless steel caps. The original attempt to clean with wire scrapers manually involved much lost time and several crews. There was limited space in the tray vessels, design created areas difficult to clean, working conditions were unpleasant, equipment downtime was extended, labor cost was high, and the final result was not satisfactory. Chemical cleaning was substituted, preceded by a water wash. Five hours of caustic wash with a 3% solution at 170$F were followed by a water wash, an acid wash, 1-hr neutralization with a weak soda ash solution, and finally passivation to eliminate iron oxide. For the acid wash, sulfamic acid was found best, in 10% concentration for 4 hr. Cascading was most economical, but flooding has been employed sometimes at 2-1/2 times the cost, to reach all the dark corners.

Diluent effects in solvent extraction. The Effects of Diluents in Solvent Extraction - a literature study

International Nuclear Information System (INIS)

Loefstroem-Engdahl, Elin; Aneheim, Emma; Ekberg, Christian; Foreman, Mark; Skarnemark, Gunnar

2010-01-01

The fact that the choice of organic diluent is important for a solvent extraction process goes without saying. Several factors, such as e.g. price, flash point, viscosity, polarity etc. each have their place in the planning of a solvent extraction system. This high number of variables makes the lack of compilations concerning diluent effects to an interesting topic. Often the interest for the research concerning a specific extraction system focuses on the extractant used and the complexes built up during an extraction. The diluents used are often classical ones, even if it has been shown that choice of diluent can affect extraction as well as separation in an extraction system. An attempt to point out important steps in the understanding of diluent effects in solvent extraction is here presented. This large field is, of course, not summarized in this article, but an attempt is made to present important steps in the understanding of diluents effects in solvent extraction. Trying to make the information concerning diluent effects and applications more easily accessible this review offers a selected summarizing of literature concerning diluents effects in solvent extraction. (authors)

Effect of solvent polarity and temperature on the spectral and thermodynamic properties of exciplexes of 1-cyanonaphthalene with hexamethylbenzene in organic solvents

Energy Technology Data Exchange (ETDEWEB)

Asim, Sadia [Institute of Physical and Theoretical Chemistry, Graz University of Technology, Stremaryrgasse 9, A-8010 Graz (Austria); Department of Chemistry and Biochemistry, University of Agriculture, Faisalabad (Pakistan); Mansha, Asim [Institute of Physical and Theoretical Chemistry, Graz University of Technology, Stremaryrgasse 9, A-8010 Graz (Austria); Department of Chemistry, Government College University, Faisalabad (Pakistan); Grampp, Günter, E-mail: grampp@tugraz.at [Institute of Physical and Theoretical Chemistry, Graz University of Technology, Stremaryrgasse 9, A-8010 Graz (Austria); Landgraf, Stephan [Institute of Physical and Theoretical Chemistry, Graz University of Technology, Stremaryrgasse 9, A-8010 Graz (Austria); Zahid, Muhammad [Institute of Physical and Theoretical Chemistry, Graz University of Technology, Stremaryrgasse 9, A-8010 Graz (Austria); Department of Chemistry and Biochemistry, University of Agriculture, Faisalabad (Pakistan); Bhatti, Ijaz Ahmad [Department of Chemistry and Biochemistry, University of Agriculture, Faisalabad (Pakistan)

2014-09-15

Study of the effect of solvent polarity and temperature is done on the exciplex emission spectra of 1-cyanonaphthalene with hexamethylbenzene. Exciplex system is studied in the range of partially polar solvents and in solvent mixture of propyl acetate and butyronitrile. The unique feature of this solvent mixture is that only the solvent polarity changes (6.0≤ε{sub s}≤24.7) with the change in the mole fraction of solvents whereas the solvent viscosity and refractive index remains unaffected. Thermodynamic properties are calculated according to the models developed by Weller and Kuzmin. Fluorescence lifetimes for both the fluorophore as well as the exciplex are evaluated in all used solvents. Exciplex energetics as a function of solvent polarity and temperature are also discussed. Kuzmin model of self-consistent polarization is used for the explanation of the exciplex emission spectra. The effects of solvent polarity and temperature on energy of zero–zero transitions (hv{sub 0}{sup /}), Huang–Rhys factor (S), Gauss broadening of vibronic level (σ) and the dominant high-frequency vibration (hν{sub ν}) are investigated. The strong dependence of exciplex stability and energetics upon the solvent polarity and temperature are observed. Full charge transfer exciplexes were observed in solvents of all polarities and stronger exciplex with large emission intensities were found in solvents of low polarities but with the increase in solvent polarity the exciplex becomes weak and they dissociate fastly into radical ion pairs. The kinetic model of Kuzmin was observed to reduce into the Weller kinetic model for this exciplex system with ∆G{sub ET} = −0.22 eV and the spectral shift, h∆ν>0.2 eV. - Highlights: • Exciplex formed as a result of mixing of charge transfer and locally excited states. • Effect of solvents polarity and temperature on the exciplex stability and thermodynamics. • Solvent polarity will decide the formation of contact radical ion pair

Reducing DRIFT backgrounds with a submicron aluminized-mylar cathode

Science.gov (United States)

Battat, J. B. R.; Daw, E.; Dorofeev, A.; Ezeribe, A. C.; Fox, J. R.; Gauvreau, J.-L.; Gold, M.; Harmon, L.; Harton, J.; Lafler, R.; Landers, J.; Lauer, R. J.; Lee, E. R.; Loomba, D.; Lumnah, A.; Matthews, J.; Miller, E. H.; Mouton, F.; Murphy, A. St. J.; Paling, S. M.; Phan, N.; Sadler, S. W.; Scarff, A.; Schuckman, F. G.; Snowden-Ifft, D.; Spooner, N. J. C.; Walker, D.

2015-09-01

Background events in the DRIFT-IId dark matter detector, mimicking potential WIMP signals, are predominantly caused by alpha decays on the central cathode in which the alpha particle is completely or partially absorbed by the cathode material. We installed a 0.9 μm thick aluminized-mylar cathode as a way to reduce the probability of producing these backgrounds. We study three generations of cathode (wire, thin-film, and radiologically clean thin-film) with a focus on the ratio of background events to alpha decays. Two independent methods of measuring the absolute alpha decay rate are used to ensure an accurate result, and agree to within 10%. Using alpha range spectroscopy, we measure the radiologically cleanest cathode version to have a contamination of 3.3±0.1 ppt 234U and 73±2 ppb 238U. This cathode reduces the probability of producing an RPR from an alpha decay by a factor of 70±20 compared to the original stainless steel wire cathode. First results are presented from a texturized version of the cathode, intended to be even more transparent to alpha particles. These efforts, along with other background reduction measures, have resulted in a drop in the observed background rate from 500/day to 1/day. With the recent implementation of full-volume fiducialization, these remaining background events are identified, allowing for background-free operation.

National Ignition Facility Incorporates P2/E2 in Aqueous Parts Cleaning of Optics Hardware

International Nuclear Information System (INIS)

Gabor, K

2001-01-01

When completed, Lawrence Livermore National Laboratory's (LLNL) National Ignition Facility (NIF) will be the world's largest laser with experimental capabilities applicable to stockpile stewardship, energy research, science and astrophysics. As construction of the conventional facilities nears completion, operations supporting the installation of specialized laser equipment have come online. Playing a critical role in the precision cleaning of mechanical parts from the NIF beamline are three pieces of aqueous cleaning equipment. Housed in the Optics Assembly Building (OAB), adjacent to NIF's laser bay, are the large mechanical parts gross cleaner (LMPGC), the large mechanical parts precision cleaner (LMPPC), and the small mechanical parts gross and precision cleaner (SMPGPC). These aqueous units, designed and built by Sonic Systems, Inc., of Newtown, Pennsylvania, not only accommodate parts that vary greatly in size, weight, geometry, surface finish and material, but also produce cleaned parts that meet the stringent NIF cleanliness standards (MIL-STD-1246C Level 83 for particles and A/10 for non-volatile residue). Each unit was designed with extensive water- and energy-conserving features, and the technology used minimizes hazardous waste generation associated with solvent wipe cleaning, the traditional method for cleaning laser mechanical components. The LMPGC provides preliminary gross cleaning for large mechanical parts. Collection, filtration and reuse of the wash and primary rinse water in the LMPGC limit its routine discharge to the volume of the low-pressure, deionized secondary rinse. After an initial gross cleaning in the LMPGC, a large mechanical part goes to the LMPPC. This piece of equipment, unique because of its size, consists of four 2700-gallon tanks. Parts held securely on specialized metal pallets (jointly weighing up to 1500 pounds) move through the tanks on an automated system. Operators program all movement, speeds and process times to

Solvent extraction studies of RERTR silicide fuels

International Nuclear Information System (INIS)

Gouge, Anthony P.

1983-01-01

Uranium silicide fuels, which are candidate RERTR fuel compositions, may require special considerations in solvent extraction reprocessing. Since Savannah River Plant may be reprocessing RERTR fuels as early as 1985, studies have been conducted at Savannah River Laboratory to demonstrate the solvent extraction behavior of this fuel. Results of solvent extraction studies with both unirradiated and irradiated fuel are presented along with the preliminary RERTR solvent extraction reprocessing flow sheet for Savannah River Plant. (author)

Manufacturing of NAA laboratory clean room

International Nuclear Information System (INIS)

Suwoto; Hasibuan, Djaruddin

2001-01-01

The ''NAA laboratory clean room'' has been built in the Reactor Serba Guna G.A. Siwabessy building. The erection of ''AAN laboratory clean room'' doing by started of preparation of the ''manufacturing procedure'' refer to ''Design and manufacturing neutron activation analysis clean room laboratory''. Manufacturing process and erection doing refer to procedures makes. By providing of the ''AAN laboratory clean room'' can be cocluded that the research activity and the user sevises in P2TRR well meet to be done

Private Exploration Primitives for Data Cleaning

OpenAIRE

Ge, Chang; Ilyas, Ihab F.; He, Xi; Machanavajjhala, Ashwin

2017-01-01

Data cleaning, or the process of detecting and repairing inaccurate or corrupt records in the data, is inherently human-driven. State of the art systems assume cleaning experts can access the data (or a sample of it) to tune the cleaning process. However, in many cases, privacy constraints disallow unfettered access to the data. To address this challenge, we observe and provide empirical evidence that data cleaning can be achieved without access to the sensitive data, but with access to a (no...

76 FR 16646 - Circadian, Inc., Clean Energy Combustion, Inc. (n/k/a Clean Energy Combustion Systems, Inc...

Science.gov (United States)

2011-03-24

... SECURITIES AND EXCHANGE COMMISSION [File No. 500-1] Circadian, Inc., Clean Energy Combustion, Inc. (n/k/a Clean Energy Combustion Systems, Inc.), Collectible Concepts Group, Inc., Communitronics of... is a lack of current and accurate information concerning the securities of Clean Energy Combustion...

Extraction, scrub, and strip test results for the salt waste processing facility caustic side solvent extraction solvent example

Energy Technology Data Exchange (ETDEWEB)

Peters, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-08-01

An Extraction, Scrub, and Strip (ESS) test was performed on a sample of Salt Waste Processing Facility (SWPF) Caustic-Side Solvent Extraction (CSSX) solvent and salt simulant to determine cesium distribution ratios (D(Cs)), and cesium concentration in the strip effluent (SE) and decontaminated salt solution (DSS) streams; this data will be used by Parsons to help determine if the solvent is qualified for use at the SWPF. The ESS test showed acceptable performance of the solvent for extraction, scrub, and strip operations. The extraction D(Cs) measured 12.9, exceeding the required value of 8. This value is consistent with results from previous ESS tests using similar solvent formulations. Similarly, scrub and strip cesium distribution ratios fell within acceptable ranges.

Carbon pricing comes clean

International Nuclear Information System (INIS)

De Wit, Elisa

2011-01-01

Together with the Clean Energy Bill, the implications of the Australian Federal Government's climate change legislative package are far reaching. Norton Rose gives business a heads-up in this breakdown of the draft legislation underpinning the carbon pricing and clean energy scheme. It is a summary of Norton Rose's full analysis.

Recent Advances in Anhydrous Solvents for CO2 Capture: Ionic Liquids, Switchable Solvents, and Nanoparticle Organic Hybrid Materials

Directory of Open Access Journals (Sweden)

YOUNGJUNE ePARK

2015-10-01

Full Text Available CO2 capture by amine scrubbing, which has a high CO2 capture capacity and a rapid reaction rate, is the most employed and investigated approach to date. There are a number of recent large-scale demonstrations including the Boundary Dam Carbon Capture Project by SaskPower in Canada that have reported successful implementations of aqueous amine solvent in CO2 capture from flue gases. The findings from these demonstrations will significantly advance the field of CO2 capture in the coming years. While the latest efforts in aqueous amine solvents are exciting and promising, there are still several drawbacks to amine-based CO2 capture solvents including high volatility and corrosiveness of the amine solutions, as well as the high parasitic energy penalty during the solvent regeneration step. Thus, in a parallel effort, alternative CO2 capture solvents, which are often anhydrous, have been developed as the third-generation CO2 capture solvents. These novel classes of liquid materials include: Ionic Liquids (ILs, CO2-triggered switchable solvents (i.e., CO2 Binding Organic Liquids (CO2BOLs, Reversible Ionic Liquids (RevILs, and Nanoparticle Organic Hybrid Materials (NOHMs. This paper provides a review of these various anhydrous solvents and their potential for CO2 capture. Particular attention is given to the mechanisms of CO2 absorption in these solvents, their regeneration and their processability – especially taking into account their viscosity. While not intended to provide a complete coverage of the existing literature, this review aims at pointing the major findings reported for these new classes of CO2 capture media.

Clean synthesis of biolubricant range esters using novel liquid lipase enzyme in solvent free medium.

Science.gov (United States)

Trivedi, Jayati; Aila, Mounika; Sharma, Chandra Dutt; Gupta, Piyush; Kaul, Savita

2015-01-01

In view of the rising global problems of environment pollution and degradation, the present process provides a 'green solution' to the synthesis of higher esters of lubricant range, more specifically in the range C12-C36, using different combinations of acids and alcohols, in a single step reaction. The esters produced are biodegradable in nature and have a plethora of uses, such as in additives, as lubricating oils and other hydraulic fluids. The enzymatic esterification was performed using liquid (non-immobilized or free) lipase enzyme, without any additional organic solvent. Soluble lipase proves to be superior to immobilized enzymes as it is more cost effective and provides a faster process for the production of higher esters of lubricant range. An interesting finding was, that the lipase enzyme showed higher conversion rates with increasing carbon number of straight chain alcohols and acids. Reactions were carried out for the optimization of initial water concentration, temperature, pH of the substrate mixture and the chain length of the substrates. Under optimized conditions, the method was suitable to achieve ~ 99% conversion. Thus, the process provides an environment friendly, enzymatic alternative to the chemical route which is currently used in the industrial synthesis of lubricant components.

Notification: Background Investigation Services New Assignment Notification: EPA’s Efforts to Incorporate Environmental Justice Into Clean Air Act Inspections for Air Toxics

Science.gov (United States)

The purpose of this memorandum is to notify you that the EPA OIG plans to begin the preliminary research phase of an evaluation of the U.S. EPA's efforts to incorporate environmental justice into Clean Air Act inspections for air toxics.

Hazardous solvent substitution

International Nuclear Information System (INIS)

Twitchell, K.E.

1995-01-01

Eliminating hazardous solvents is good for the environment, worker safety, and the bottom line. However, even though we are motivated to find replacements, the big question is 'What can we use as replacements for hazardous solvents?'You, too, can find replacements for your hazardous solvents. All you have to do is search for them. Search through the vendor literature of hundreds of companies with thousands of products. Ponder the associated material safety data sheets, assuming of course that you can obtain them and, having obtained them, that you can read them. You will want to search the trade magazines and other sources for product reviews. You will want to talk to users about how well the product actually works. You may also want to check US Environmental Protection Agency (EPA) and other government reports for toxicity and other safety information. And, of course, you will want to compare the product's constituent chemicals with the many hazardous constituency lists to ensure the safe and legal use of the product in your workplace

Sonochemical cleaning efficiencies in dental instruments

Science.gov (United States)

Tiong, T. Joyce; Walmsley, A. Damien; Price, Gareth J.

2012-05-01

Ultrasound has been widely used for cleaning purposes in a variety of situations, including in dental practice. Cleaning is achieved through a combination of acoustically driven streaming effects and sonochemical effects arising from the production of inertial cavitation in a liquid. In our work, various dental instruments used for endodontic (root canal) treatment have been evaluated for their efficiency in producing sonochemical effects in an in-vitro cleaning environment. The areas where cavitation was produced were mapped by monitoring chemiluminescence from luminol solutions and this was correlated with their cleaning efficiencies - assessed by the ability to bleach a dye, to form an emulsion by mixing immiscible components and also to remove ink from a glass surface. The results showed good correlation (Pearson's coefficient > 0.9) between the cavitation and cleaning efficiencies, suggesting that the former plays an important role in cleaning. The methods developed and the results will be beneficial in endodontics research in order to optimise future root canal instruments and treatments.

Investigation and feasibility study of a former manufactured gas plant site in Tuttlingen (Germany), based on individually determined clean-up criteria

Energy Technology Data Exchange (ETDEWEB)

Heinecker, C.; Pickel, H.-J.; Duffek, J. [HPC Harress Pickel Consult GmbH, Fuldatal (Germany)

1995-12-31

At the request of the former plant operator, a manufactured gas plant site in Tuttlingen, Germany, was investigated from 1988 through 1992 for subsurface soil contamination resulting from former activities. In 1991, the contents of the former tar pits and parts of the adjacent soil contaminations were removed in the course of clean-up activities by means of excavation and disposed at a special waste site. Following an initial risk assessment, a remedial investigation was carried out in order to further delineate the contaminated areas as well as to create a reliable database for a feasibility study of remedial alternatives. The feasibility study followed applicable Baden-Wurttemberg state guidelines, including the following elements: Determination of the clean-up goals for soils; pre-selection of the clean-up procedure; cost estimate; cost-effectiveness study; Non-monetary evaluation; and total evaluation/clean-up proposal. The following general alternatives were available for the definition of clean-up goals: background values (`H-values`); general guidelines values (`SZ-values`); and clean-up goals based on contaminant fate and transport as well as site use (`SZA-values`).

Uniquely Strongly Clean Group Rings

Institute of Scientific and Technical Information of China (English)

WANG XIU-LAN

2012-01-01

A ring R is called clean if every element is the sum of an idempotent and a unit,and R is called uniquely strongly clean (USC for short) if every element is uniquely the sum of an idempotent and a unit that commute.In this article,some conditions on a ring R and a group G such that RG is clean are given.It is also shown that if G is a locally finite group,then the group ring RG is USC if and only if R is USC,and G is a 2-group.The left uniquely exchange group ring,as a middle ring of the uniquely clean ring and the USC ring,does not possess this property,and so does the uniquely exchange group ring.

Recent solvent extraction experience at Savannah River

International Nuclear Information System (INIS)

Gray, L.W.; Burney, G.A.; Gray, J.H.; Hodges, M.E.; Holt, D.L.; Macafee, I.M.; Reif, D.J.; Shook, H.E.

1986-01-01

Tributyl phosphate-based solvent extraction processes have been used at Savannah River for more than 30 years to separate and purify thorium, uranium, neptunium, plutonium, americium, and curium isotopes. This report summarizes the advancement of solvent extraction technology at Savannah River during the 1980's. Topics that are discussed include equipment improvements, solvent treatment, waste reduction, and an improved understanding of the various chemistries in the process streams entering, within, and leaving the solvent extraction processes

Clean Coal Day '94 Hokkaido International Seminar; Clean coal day '94 Hokkaido kokusai seminar

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-06-01

The lectures given at the seminar were 1) Coal energy be friendly toward the earth, 2) Clean coal technology in the United Kingdom, and 3) How clean coal should be in Australia. In lecture 1), remarks are made on the importance of coal and its future, coal that protects forest, whether coal is a dirty fuel, coal combustion tests started relative to environmental pollution, acid rain in China and coal combustion, briquets effective in energy conservation, etc. In lecture 2), remarks are made on the importance of coal utilization in the United Kingdom, current state of coal utilization in power generation, problems related to gasification furnaces, problems related to combustors, problems related to high-temperature gas cleaning, function of cleaning filters, advantages of high-temperature gas treatment, actualities of gas combustors, studies of gas combustors, etc. In lecture 3), remarks are made on Australia's coal situation, problems related to clean coal technology, problems related to coal preparation technology, potentialities of Australian brown coal, coal utilization in power generation, need of new technology development, current state of coal utilization in Australia, coal utilization in metal-making industry, international cooperation on technology, etc. (NEDO)

Effects of temperature and solvent concentration on the solvent crystallization of palm-based dihydroxystearic acid with isopropyl alcohol

Institute of Scientific and Technical Information of China (English)

Gregory F.L.Koay; Teong-Guan Chuah; Sumaiya Zainal-Abidin; Salmiah Ahmad; Thomas S.Y.Choong

2012-01-01

Palm-based dihydroxystearic acid of 69.55％ purity was produced in a 500-kg-per-batch operation pilot plant and purified through solvent crystallization in a custom fabricated simultaneous batch crystallizer unit.The effects of temperature and solvent concentration on yield,particle size distribution and purity were studied.The purity was higher,while the yield and particle size were lower and smaller,respectively,at higher temperature and solvent concentration.The solvent crystallization process efficiency was rated at 66-69％ when carried out with 70-80％ isopropyl alcohol at 20 ℃.

Rudimentary Cleaning Compared to Level 300A

Science.gov (United States)

Arpin, Christina Y. Pina; Stoltzfus, Joel

2012-01-01

A study was done to characterize the cleanliness level achievable when using a rudimentary cleaning process, and results were compared to JPR 5322.1G Level 300A. While it is not ideal to clean in a shop environment, some situations (e.g., field combat operations) require oxygen system hardware to be maintained and cleaned to prevent a fire hazard, even though it cannot be sent back to a precision cleaning facility. This study measured the effectiveness of basic shop cleaning. Initially, three items representing parts of an oxygen system were contaminated: a metal plate, valve body, and metal oxygen bottle. The contaminants chosen were those most likely to be introduced to the system during normal use: oil, lubricant, metal shavings/powder, sand, fingerprints, tape, lip balm, and hand lotion. The cleaning process used hot water, soap, various brushes, gaseous nitrogen, water nozzle, plastic trays, scouring pads, and a controlled shop environment. Test subjects were classified into three groups: technical professionals having an appreciation for oxygen hazards; professional precision cleaners; and a group with no previous professional knowledge of oxygen or precision cleaning. Three test subjects were in each group, and each was provided with standard cleaning equipment, a cleaning procedure, and one of each of the three test items to clean. The results indicated that the achievable cleanliness level was independent of the technical knowledge or proficiency of the personnel cleaning the items. Results also showed that achieving a Level 300 particle count was more difficult than achieving a Level A nonvolatile residue amount.

Cleaning metal filters by pulse-jet

International Nuclear Information System (INIS)

Pickard, P.; Perry, R.A.

1986-01-01

Cleanable metal filters have an established use in the Nuclear Industry. The filters that have been installed in the past have not proved to be sufficiently cleanable. A series of tests were undertaken to study the application of pulse-jet cleaning to metal fibre filter elements. The efficiency of dust removal was examined under various operating conditions. A very high degree of particulate removal was achieved, with a return to almost clean pressure drop. The effectiveness of cleaning was found to vary inversely with blowback pressure. The position of the blowback nozzle with respect to the filter element throat was also found to be important to cleaning efficiency. Under the test conditions the effect of re-entrainment when cleaning on line was found to be minimal. (author)

Solvents interactions with thermochromic print

Directory of Open Access Journals (Sweden)

Mirela Rožić

2017-12-01

Full Text Available In this study, the interactions between different solvents (benzene, acetone, cyclohexanone, various alcohols and water and thermochromic printing ink were investigated. Thermochromic printing ink was printed on metal surface. Components of thermochromic printing inks are polymeric microcapsules and classic yellow offset printing ink. Below its activation temperature, dye and developer within the microcapsules form a blue coloured complex. Therefore, thermochromic print is green. By heating above the activation temperature, blue colour of the complex turns into the leuco dye colourless state and the green colour of the prints turns into the yellow colour of the classic offset pigment. The results of the interaction with various solvents show that the thermochromic print is stable in all tested solvents except in ethanol, acetone and cyclohexanone. In ethanol, the green colour of the print becomes yellow. SEM analysis shows that microcapsules are dissolved. In acetone and cyclohexanone, the green colour of the print turns into blue, and the microcapsules become significantly more visible. Thus, the yellow pigment interacts with examined ketones. Based on the obtained interactions it can be concluded that the microcapsules have more polar nature than the classical pigment particles. Solvent-thermocromic print interactions were analysed using Hansen solubility parameters that rank the solvents based on their estimated interaction capabilities.

Photoresist removal using gaseous sulfur trioxide cleaning technology

Science.gov (United States)

Del Puppo, Helene; Bocian, Paul B.; Waleh, Ahmad

1999-06-01

A novel cleaning method for removing photoresists and organic polymers from semiconductor wafers is described. This non-plasma method uses anhydrous sulfur trioxide gas in a two-step process, during which, the substrate is first exposed to SO3 vapor at relatively low temperatures and then is rinsed with de-ionized water. The process is radically different from conventional plasma-ashing methods in that the photoresist is not etched or removed during the exposure to SO3. Rather, the removal of the modified photoresist takes place during the subsequent DI-water rinse step. The SO3 process completely removes photoresist and polymer residues in many post-etch applications. Additional advantages of the process are absence of halogen gases and elimination of the need for other solvents and wet chemicals. The process also enjoys a very low cost of ownership and has minimal environmental impact. The SEM and SIMS surface analysis results are presented to show the effectiveness of gaseous SO3 process after polysilicon, metal an oxide etch applications. The effects of both chlorine- and fluorine-based plasma chemistries on resist removal are described.

Washing away your sins in the brain: physical cleaning and priming of cleaning recruit different brain networks after moral threat.

Science.gov (United States)

Tang, Honghong; Lu, Xiaping; Su, Rui; Liang, Zilu; Mai, Xiaoqin; Liu, Chao

2017-07-01

The association between moral purity and physical cleanliness has been widely discussed recently. Studies found that moral threat initiates the need of physical cleanliness, but actual physical cleaning and priming of cleaning have inconsistent effects on subsequent attitudes and behaviors. Here, we used resting-state functional magnetic resonance imaging to explore the underlying neural mechanism of actual physical cleaning and priming of cleaning. After recalling moral transgression with strong feelings of guilt and shame, participants either actually cleaned their faces with a wipe or were primed with cleanliness through viewing its pictures. Results showed that actual physical cleaning reduced the spontaneous brain activities in the right insula and MPFC, regions that involved in embodied moral emotion processing, while priming of cleaning decreased activities in the right superior frontal gyrus and middle frontal gyrus, regions that participated in executive control processing. Additionally, actual physical cleaning also changed functional connectivity between insula/MPFC and emotion related regions, whereas priming of cleaning modified connectivity within both moral and sensorimotor areas. These findings revealed that actual physical cleaning and priming of cleaning led to changes in different brain regions and networks, providing neural evidence for the inconsistent effects of cleanliness on subsequent attitudes and behaviors. © The Author (2017). Published by Oxford University Press.

Density Changes in the Optimized CSSX Solvent System

Energy Technology Data Exchange (ETDEWEB)

Lee, D.D.

2002-11-25

Density increases in caustic-side solvent extraction (CSSX) solvent have been observed in separate experimental programs performed by different groups of researchers. Such changes indicate a change in chemical composition. Increased density adversely affects separation of solvent from denser aqueous solutions present in the CSSX process. Identification and control of factors affecting solvent density are essential for design and operation of the centrifugal contactors. The goals of this research were to identify the factors affecting solvent density (composition) and to develop correlations between easily measured solvent properties (density and viscosity) and the chemical composition of the solvent, which will permit real-time determination and adjustment of the solvent composition. In evaporation experiments, virgin solvent was subjected to evaporation under quiescent conditions at 25, 35, and 45 C with continuously flowing dry air passing over the surface of the solvent. Density and viscosity were measured periodically, and chemical analysis was performed on the solvent samples. Chemical interaction tests were completed to determine if any chemical reaction takes place over extended contact time that changes the composition and/or physical properties. Solvent and simulant, solvent and strip solution, and solvent and wash solution were contacted continuously in agitated flasks. They were periodically sampled and the density measured (viscosity was also measured on some samples) and then submitted to the Chemical Sciences Division of Oak Ridge National Laboratory for analysis by nuclear magnetic resonance (NMR) spectrometry and high-performance liquid chromatography (HPLC) using the virgin solvent as the baseline. Chemical interaction tests showed that solvent densities and viscosities did not change appreciably during contact with simulant, strip, or wash solution. No effects on density and viscosity and no chemical changes in the solvent were noted within

PARIS II: Computer Aided Solvent Design for Pollution Prevention

Science.gov (United States)

This product is a summary of U.S. EPA researchers' work developing the solvent substitution software tool PARIS II (Program for Assisting the Replacement of Industrial Solvents, version 2.0). PARIS II finds less toxic solvents or solvent mixtures to replace more toxic solvents co...

Organic solvents in electromembrane extraction: recent insights

DEFF Research Database (Denmark)

Huang, Chuixiu; Gjelstad, Astrid; Pedersen-Bjergaard, Stig

2016-01-01

the introduction. Under the influence of an electrical field, EME is based on electrokinetic migration of the analytes through a supported liquid membrane (SLM), which is an organic solvent immobilized in the pores of the polymeric membrane, and into the acceptor solution. Up to date, close to 150 research...... articles with focus on EME have been published. The current review summarizes the performance of EME with different organic solvents and discusses several criteria for efficient solvents in EME. In addition, the authors highlight their personal perspective about the most promising organic solvents for EME...... and have indicated that more fundamental work is required to investigate and discover new organic solvents for EME....

Dendritic brushes under theta and poor solvent conditions

Science.gov (United States)

Gergidis, Leonidas N.; Kalogirou, Andreas; Charalambopoulos, Antonios; Vlahos, Costas

2013-07-01

The effects of solvent quality on the internal stratification of polymer brushes formed by dendron polymers up to third generation were studied by means of molecular dynamics simulations with Langevin thermostat. The distributions of polymer units, of the free ends, the radii of gyration, and the back folding probabilities of the dendritic spacers were studied at the macroscopic states of theta and poor solvent. For high grafting densities we observed a small decrease in the height of the brush as the solvent quality decreases. The internal stratification in theta solvent was similar to the one we found in good solvent, with two and in some cases three kinds of populations containing short dendrons with weakly extended spacers, intermediate-height dendrons, and tall dendrons with highly stretched spacers. The differences increase as the grafting density decreases and single dendron populations were evident in theta and poor solvent. In poor solvent at low grafting densities, solvent micelles, polymeric pinned lamellae, spherical and single chain collapsed micelles were observed. The scaling dependence of the height of the dendritic brush at high density brushes for both solvents was found to be in agreement with existing analytical results.

Advances in telescope mirror cleaning

Science.gov (United States)

Blanken, Maarten F.; Chopping, Alan K.; Dee, Kevin M.

2004-09-01

Metrology and cleaning techniques for telescope mirrors are generally well established. CO2 cleaning and water washing are mainly used. Water washing has proven to be the best method of removing oil and water stains and restoring the aluminium to nearly fresh values. The risk of water getting to unwanted places such as electronics or other optics prevents this method from being employed more often. Recently the Isaac Newton Group introduced a new cleaning technique for their telescope mirrors, which reduces the risks discussed above. This technique uses water vapour instead of water to wash the mirror. The advantage of this method is that the amount of water needed is drastically reduced. In addition the pressure of the vapour will blow away any large dust particles on the mirror and the temperature shock between the vapour and the mirror will help to de-bond the dust particles. Adding a soapy solution will help to clean oil and watermarks of the mirror. This paper describes the vapour cleaning method, tests that have been done and the overall findings.

An absorbing microwave micro-solid-phase extraction device used in non-polar solvent microwave-assisted extraction for the determination of organophosphorus pesticides

International Nuclear Information System (INIS)

Wang Ziming; Zhao Xin; Xu Xu; Wu Lijie; Su Rui; Zhao Yajing; Jiang Chengfei; Zhang Hanqi; Ma Qiang; Lu Chunmei; Dong Deming

2013-01-01

Highlights: ► An absorbing microwave μ-SPE device packed with activated carbon was used. ► Absorbing microwave μ-SPE device was made and used to enrich the analytes. ► Absorbing microwave μ-SPE device was made and used to heat samples directly. ► MAE-μ-SPE was applied to the extraction of OPPs with non-polar solvent only. - Abstract: A single-step extraction-cleanup method, including microwave-assisted extraction (MAE) and micro-solid-phase extraction (μ-SPE), was developed for the extraction of ten organophosphorus pesticides in vegetable and fruit samples. Without adding any polar solvent, only one kind of non-polar solvent (hexane) was used as extraction solvent in the whole extraction step. Absorbing microwave μ-SPE device, was prepared by packing activated carbon with microporous polypropylene membrane envelope, and used as not only the sorbent in μ-SPE, but also the microwave absorption medium. Some experimental parameters effecting on extraction efficiency was investigated and optimized. 1.0 g of sample, 8 mL of hexane and three absorbing microwave μ-SPE devices were added in the microwave extraction vessel, the extraction was carried out under 400 W irradiation power at 60 °C for 10 min. The extracts obtained by MAE-μ-SPE were directly analyzed by GC–MS without any clean-up process. The recoveries were in the range of 93.5–104.6%, and the relative standard deviations were lower than 8.7%.

Power generation from chemically cleaned coals: do environmental benefits of firing cleaner coal outweigh environmental burden of cleaning?

DEFF Research Database (Denmark)

Ryberg, Morten W.; Owsianiak, Mikolaj; Laurent, Alexis

2015-01-01

Power generation from high-ash coals is a niche technology for power generation, but coal cleaning is deemed necessary to avoid problems associated with low combustion efficiencies and to minimize environmental burdens associated with emissions of pollutants originating from ash. Here, chemical...... beneficiation of coals using acid and alkali–acid leaching procedures is evaluated as a potential coal cleaning technology employing life cycle assessment (LCA). Taking into account the environmental benefits from firing cleaner coal in pulverized coal power plants and the environmental burden of the cleaning...... itself, it is demonstrated that for a wide range of cleaning procedures and types of coal, chemical cleaning generally performs worse than combustion of the raw coals and physical cleaning using dense medium separation. These findings apply for many relevant impact categories, including climate change...

Coolant clean-up system in nuclear reactor

International Nuclear Information System (INIS)

Tsuburaya, Hirobumi; Akita, Minoru; Shiraishi, Tadashi; Kinoshita, Shoichiro; Okura, Minoru; Tsuji, Akio.

1987-01-01

Purpose: To ensure a sufficient urging pressure at the inlet of a coolant clean-up system pump in a nuclear reactor and eliminate radioactive contaminations to the pump. Constitution: Coolant clean-up system (CUW) pump in a nuclear reactor is disposed to the downstream of a filtration desalter and, for compensating the insufficiency of the urging pressure at the pump inlet, the reactor water intake port to the clean-up system is disposed to the downstream of the after-heat removing pump and the heat exchanger. By compensating the net positive suction head (NPSH) of the clean-up system from the residual heat removing system, the problems of insufficient NPSH for the CUW pump upon reactor shut-down can be dissolved and, accordingly, the reactor clean-up system can be arranged in the order of the heat exchanger, clean-up device and pump. Thus, the CUW pump acts on reactor water after cleaned-up in the clean-up device to reduce the radioactivity contamination to the pump. (Kawakami, Y.)

49 CFR 174.615 - Cleaning cars.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Cleaning cars. 174.615 Section 174.615... Requirements for Division 6.1 (Poisonous) Materials § 174.615 Cleaning cars. (a) [Reserved] (b) After Division 6.1 (poisonous) materials are unloaded from a rail car, that car must be thoroughly cleaned unless...

Effectuality of Cleaning Workers' Training and Cleaning Enterprises' Chemical Health Hazard Risk Profiling.

Science.gov (United States)

Suleiman, Abdulqadir M; Svendsen, Kristin V H

2015-12-01

Goal-oriented communication of risk of hazards is necessary in order to reduce risk of workers' exposure to chemicals. Adequate training of workers and enterprise priority setting are essential elements. Cleaning enterprises have many challenges and the existing paradigms influence the risk levels of these enterprises. Information on organization and enterprises' prioritization in training programs was gathered from cleaning enterprises. A measure of enterprises' conceptual level of importance of chemical health hazards and a model for working out the risk index (RI) indicating enterprises' conceptual risk level was established and used to categorize the enterprises. In 72.3% of cases, training takes place concurrently with task performances and in 67.4% experienced workers conduct the trainings. There is disparity between employers' opinion on competence level of the workers and reality. Lower conceptual level of importance was observed for cleaning enterprises of different sizes compared with regional safety delegates and occupational hygienists. Risk index values show no difference in risk level between small and large enterprises. Training of cleaning workers lacks the prerequisite for suitability and effectiveness to counter risks of chemical health hazards. There is dereliction of duty by management in the sector resulting in a lack of competence among the cleaning workers. Instituting acceptable easily attainable safety competence level for cleaners will conduce to risk reduction, and enforcement of attainment of the competence level would be a positive step.

Sum Frequency Generation Vibrational Spectroscopy of Colloidal Platinum Nanoparticle Catalysts: Disordering versus Removal of Organic Capping

KAUST Repository

Krier, James M.

2012-08-23

Recent work with nanoparticle catalysts shows that size and shape control on the nanometer scale influences reaction rate and selectivity. Sum frequency generation (SFG) vibrational spectroscopy is a powerful tool for studying heterogeneous catalysis because it enables the observation of surface intermediates during catalytic reactions. To control the size and shape of catalytic nanoparticles, an organic ligand was used as a capping agent to stabilize nanoparticles during synthesis. However, the presence of an organic capping agent presents two major challenges in SFG and catalytic reaction studies: it blocks a significant fraction of active surface sites and produces a strong signal that prevents the detection of reaction intermediates with SFG. Two methods for cleaning Pt nanoparticles capped with poly (vinylpyrrolidone) (PVP) are examined in this study: solvent cleaning and UV cleaning. Solvent cleaning leaves more PVP intact and relies on disordering with hydrogen gas to reduce the SFG signal of PVP. In contrast, UV cleaning depends on nearly complete removal of PVP to reduce SFG signal. Both UV and solvent cleaning enable the detection of reaction intermediates by SFG. However, solvent cleaning also yields nanoparticles that are stable under reaction conditions, whereas UV cleaning results in aggregation during reaction. The results of this study indicate that solvent cleaning is more advantageous for studying the effects of nanoparticle size and shape on catalytic selectivity by SFG vibrational spectroscopy. © 2012 American Chemical Society.

Discharge cleaning for a tokamak

International Nuclear Information System (INIS)

Ishii, Shigeyuki

1983-01-01

Various methods of discharge cleaning for tokamaks are described. The material of the first walls of tokamaks is usually stainless steel, inconel, titanium and so on. Hydrogen is exclusively used as the discharge gas. Glow discharge cleaning (GDC), Taylor discharge cleaning (TDC), and electron cyclotron resonance discharge cleaning (ECR-DC) are discussed in this paper. The cleaning by GDC is made by moving a movable anode to the center of a tokamak vassel. Taylor found the good cleaning effect of induced discharge by high pressure and low power discharge. This is called TDC. When the frequency of high frequency discharge in a magnetic field is equal to that of the electron cyclotron resonance, the break down potential is lowered if the pressure is sufficiently low. The ECR-CD is made by using this effect. In TDC and ECR-DC, the electron temperature, which has a close relation to the production rate of H 0 , can be controlled by the pressure. In GDC, the operating pressure was improved by the radio frequency glow (RG) method. However, there is still the danger of arcing. In case of GDC and ECR-DC, the position of plasma can be controlled, but not in case of TDC. The TDC is accepted by most of takamak devices in the world. (Kato, T.)

40 CFR Table 3 to Subpart Pppp of... - Default Organic HAP Mass Fraction for Solvents and Solvent Blends

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Default Organic HAP Mass Fraction for... Organic HAP Mass Fraction for Solvents and Solvent Blends You may use the mass fraction values in the... solvent blend matches both the name and CAS number for an entry, that entry's organic HAP mass fraction...

Acrylic vessel cleaning tests

International Nuclear Information System (INIS)

Earle, D.; Hahn, R.L.; Boger, J.; Bonvin, E.

1997-01-01

The acrylic vessel as constructed is dirty. The dirt includes blue tape, Al tape, grease pencil, gemak, the glue or residue form these tapes, finger prints and dust of an unknown composition but probably mostly acrylic dust. This dirt has to be removed and once removed, the vessel has to be kept clean or at least to be easily cleanable at some future stage when access becomes much more difficult. The authors report on the results of a series of tests designed: (a) to prepare typical dirty samples of acrylic; (b) to remove dirt stuck to the acrylic surface; and (c) to measure the optical quality and Th concentration after cleaning. Specifications of the vessel call for very low levels of Th which could come from tape residues, the grease pencil, or other sources of dirt. This report does not address the concerns of how to keep the vessel clean after an initial cleaning and during the removal of the scaffolding. Alconox is recommended as the cleaner of choice. This acrylic vessel will be used in the Sudbury Neutrino Observatory

Clean-room robot implementation

International Nuclear Information System (INIS)

Comeau, J.L.

1982-01-01

A robot has been incorporated in a clean room operation in which vacuum tube parts are cleaned just prior to final assembly with a 60 lb/in 2 blast of argon gas. The robot is programmed to pick up the parts, manipulate/rotate them as necessary in the jet pattern and deposit them in a tray precleaned by the robot. A carefully studied implementation plan was followed in the procurement, installation, modification and programming of the robot facility. An unusual configuration of one tube part required a unique gripper design. A study indicated that the tube parts processed by the robot are 12% cleaner than those manually cleaned by an experienced operator

40 CFR 52.254 - Organic solvent usage.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Organic solvent usage. 52.254 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS California § 52.254 Organic solvent usage. (a) This... (d) of this section and the architectural coatings and solvent disposal emission limitations...

27 CFR 21.125 - Rubber hydrocarbon solvent.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Rubber hydrocarbon solvent. 21.125 Section 21.125 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU....125 Rubber hydrocarbon solvent. (a) Rubber hydrocarbon solvent is a petroleum derivative. (b...

Outsourcing Housekeeping: An insight into two cleaning companies, SOL and N-Clean, in Helsinki, Finland

OpenAIRE

Hussain, Samra

2016-01-01

The purpose of the author was to find to get an insight into the cleaning companies, in Helsin-ki, Finland, which the hotel industry is using as an external supplier for their housekeeping de-partment. The author has looked into the cleaning companies training process for the cleaning staff, employee demographics, quality control and process of handling complaints. The ad-vantages and disadvantages of outsourcing housekeeping in the hotel sector are also investi-gated. The research method...

The spectral properties of (--epigallocatechin 3-O-gallate (EGCG fluorescence in different solvents: dependence on solvent polarity.

Directory of Open Access Journals (Sweden)

Vladislav Snitsarev

Full Text Available (--Epigallocatechin 3-O-gallate (EGCG a molecule found in green tea and known for a plethora of bioactive properties is an inhibitor of heat shock protein 90 (HSP90, a protein of interest as a target for cancer and neuroprotection. Determination of the spectral properties of EGCG fluorescence in environments similar to those of binding sites found in proteins provides an important tool to directly study protein-EGCG interactions. The goal of this study is to examine the spectral properties of EGCG fluorescence in an aqueous buffer (AB at pH=7.0, acetonitrile (AN (a polar aprotic solvent, dimethylsulfoxide (DMSO (a polar aprotic solvent, and ethanol (EtOH (a polar protic solvent. We demonstrate that EGCG is a highly fluorescent molecule when excited at approximately 275 nm with emission maxima between 350 and 400 nm depending on solvent. Another smaller excitation peak was found when EGCG is excited at approximately 235 nm with maximum emission between 340 and 400 nm. We found that the fluorescence intensity (FI of EGCG in AB at pH=7.0 is significantly quenched, and that it is about 85 times higher in an aprotic solvent DMSO. The Stokes shifts of EGCG fluorescence were determined by solvent polarity. In addition, while the emission maxima of EGCG fluorescence in AB, DMSO, and EtOH follow the Lippert-Mataga equation, its fluorescence in AN points to non-specific solvent effects on EGCG fluorescence. We conclude that significant solvent-dependent changes in both fluorescence intensity and fluorescence emission shifts can be effectively used to distinguish EGCG in aqueous solutions from EGCG in environments of different polarity, and, thus, can be used to study specific EGCG binding to protein binding sites where the environment is often different from aqueous in terms of polarity.

Clean Energy Solutions Center Services

Energy Technology Data Exchange (ETDEWEB)

2016-03-01

The Solutions Center offers no-cost expert policy assistance, webinars and training forums, clean energy policy reports, data, and tools provided in partnership with more than 35 leading international and regional clean energy organizations.

40 CFR Table 3 to Subpart Mmmm of... - Default Organic HAP Mass Fraction for Solvents and Solvent Blends

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Default Organic HAP Mass Fraction for... Part 63—Default Organic HAP Mass Fraction for Solvents and Solvent Blends You may use the mass fraction.... If a solvent blend matches both the name and CAS number for an entry, that entry's organic HAP mass...

Separation by solvent extraction

International Nuclear Information System (INIS)

Holt, C.H. Jr.

1976-01-01

In a process for separating fission product values from U and Pu values contained in an aqueous solution, an oxidizing agent is added to the solution to secure U and Pu in their hexavalent state. The aqueous solution is contacted with a substantially water-immiscible organic solvent with agitation while the temperature is maintained at from -1 to -2 0 C until the major part of the water present is frozen. The solid ice phase is continuously separated as it is formed and a remaining aqueous liquid phase containing fission product values and a solvent phase containing Pu and U values are separated from each other. The last obtained part of the ice phase is melted and added to the separated liquid phase. The resulting liquid is treated with a new supply of solvent whereby it is practically depleted of U and Pu

Emulsion type dry cleaning system

International Nuclear Information System (INIS)

Kohanawa, Osamu; Matsumoto, Hiroyo.

1988-01-01

Protective clothing against radioactive contamination used in the radiation controlled areas of nuclear plants has been washed by the same wet washing as used for underwear washing, but recently dry cleaning is getting used in place of wet washing, which generates a large quantity of laundry drain. However, it was required to use wet washing once every five to ten dry cleanings for washing protective clothing, because conventional dry cleaning is less effective in removing water-soluble soils. Therefore, in order to eliminate wet washing, and to decrease the quantity of laundry drains, the emulsion type dry cleaning system capable of removing both oil-soluble and water-soluble soils at a time has been developed. The results of developmental experiments and actual application are presented in this paper. (author)

Risk in cleaning: chemical and physical exposure.

Science.gov (United States)

Wolkoff, P; Schneider, T; Kildesø, J; Degerth, R; Jaroszewski, M; Schunk, H

1998-04-23

Cleaning is a large enterprise involving a large fraction of the workforce worldwide. A broad spectrum of cleaning agents has been developed to facilitate dust and dirt removal, for disinfection and surface maintenance. The cleaning agents are used in large quantities throughout the world. Although a complex pattern of exposure to cleaning agents and resulting health problems, such as allergies and asthma, are reported among cleaners, only a few surveys of this type of product have been performed. This paper gives a broad introduction to cleaning agents and the impact of cleaning on cleaners, occupants of indoor environments, and the quality of cleaning. Cleaning agents are usually grouped into different product categories according to their technical functions and the purpose of their use (e.g. disinfectants and surface care products). The paper also indicates the adverse health and comfort effects associated with the use of these agents in connection with the cleaning process. The paper identifies disinfectants as the most hazardous group of cleaning agents. Cleaning agents contain evaporative and non-evaporative substances. The major toxicologically significant constituents of the former are volatile organic compounds (VOCs), defined as substances with boiling points in the range of 0 degree C to about 400 degrees C. Although laboratory emission testing has shown many VOCs with quite different time-concentration profiles, few field studies have been carried out measuring the exposure of cleaners. However, both field studies and emission testing indicate that the use of cleaning agents results in a temporal increase in the overall VOC level. This increase may occur during the cleaning process and thus it can enhance the probability of increased short-term exposure of the cleaners. However, the increased levels can also be present after the cleaning and result in an overall increased VOC level that can possibly affect the indoor air quality (IAQ) perceived by

Molecular Thermodynamic Modeling of Mixed Solvent Solubility

DEFF Research Database (Denmark)

Ellegaard, Martin Dela; Abildskov, Jens; O’Connell, John P.

2010-01-01

A method based on statistical mechanical fluctuation solution theory for composition derivatives of activity coefficients is employed for estimating dilute solubilities of 11 solid pharmaceutical solutes in nearly 70 mixed aqueous and nonaqueous solvent systems. The solvent mixtures range from...... nearly ideal to strongly nonideal. The database covers a temperature range from 293 to 323 K. Comparisons with available data and other existing solubility methods show that the method successfully describes a variety of observed mixed solvent solubility behaviors using solute−solvent parameters from...

Solvent distillations studies for a reprocessing plant

International Nuclear Information System (INIS)

Ginisty, C.; Guillaume, B.

1989-01-01

The substantial amounts of solvent used in large reprocessing plants are such that considerable care must be paid to solvent management to limit the production of organic wastes. The installation of intensive treatment by chemical regeneration serves to increase the service life of the solvent. General solvent management, combined with a distillation unit under reduced pressure also helps to recycle the two components of the solvent at a low activity level. Distillation also serves to remove the heavy degradation products that are generally responsible for poor hydraulic behavior and for the holdup of radioactive products such as plutonium, zirconium and ruthenium. From the safety standpoint, the flashpoint of the distilled diluent tends to rise. It can therefore be recycled without risk

Clean Energy Policy Analyses: Analysis of the Status and Impact of Clean Energy Policies at the Local Level

Energy Technology Data Exchange (ETDEWEB)

Busche, S.

2010-12-01

This report takes a broad look at the status of local clean energy policies in the United States to develop a better understanding of local clean energy policy development and the interaction between state and local policies. To date, the majority of clean energy policy research focuses on the state and federal levels. While there has been a substantial amount of research on local level climate change initiatives, this is one of the first analyses of clean energy policies separate from climate change initiatives. This report is one in a suite of reports analyzing clean energy and climate policy development at the local, state, and regional levels.

Clean Energy Policy Analyses. Analysis of the Status and Impact of Clean Energy Policies at the Local Level

Energy Technology Data Exchange (ETDEWEB)

Busche, S. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2010-12-01

This report takes a broad look at the status of local clean energy policies in the United States to develop a better understanding of local clean energy policy development and the interaction between state and local policies. To date, the majority of clean energy policy research focuses on the state and federal levels. While there has been a substantial amount of research on local level climate change initiatives, this is one of the first analyses of clean energy policies separate from climate change initiatives. This report is one in a suite of reports analyzing clean energy and climate policy development at the local, state, and regional levels.

Trace Analysis in End-Exhaled Air Using Direct Solvent Extraction in Gas Sampling Tubes: Tetrachloroethene in Workers as an Example

Directory of Open Access Journals (Sweden)

Chris-Elmo Ziener

2014-01-01

Full Text Available Simple and cost-effective analytical methods are required to overcome the barriers preventing the use of exhaled air in routine occupational biological monitoring. Against this background, a new method is proposed that simplifies the automation and calibration of the analytical measurements. End-exhaled air is sampled using valveless gas sampling tubes made of glass. Gaseous analytes are transferred to a liquid phase using a microscale solvent extraction performed directly inside the gas sampling tubes. The liquid extracts are analysed using a gas chromatograph equipped, as usual, with a liquid autosampler, and liquid standards are used for calibration. For demonstration purposes, the method’s concept was applied to the determination of tetrachloroethene in end-exhaled air, which is a biomarker for occupational tetrachloroethene exposure. The method’s performance was investigated in the concentration range 2 to 20 μg tetrachloroethene/L, which corresponds to today’s exposure levels. The calibration curve was linear, and the intra-assay repeatability and recovery rate were sufficient. Analysis of real samples from dry-cleaning workers occupationally exposed to tetrachloroethene and from nonexposed subjects demonstrated the method’s utility. In the case of tetrachloroethene, the method can be deployed quickly, requires no previous experiences in gas analysis, provides sufficient analytical reliability, and addresses typical end-exhaled air concentrations from exposed workers.

Handbook of organic solvent properties

CERN Document Server

Smallwood, Ian

2012-01-01

The properties of 72 of the most commonly used solvents are given, tabulated in the most convenient way, making this book a joy for industrial chemists to use as a desk reference. The properties covered are those which answer the basic questions of: Will it do the job? Will it harm the user? Will it pollute the air? Is it easy to handle? Will it pollute the water? Can it be recovered or incinerated? These are all factors that need to be considered at the early stages of choosing a solvent for a new product or process.A collection of the physical properties of most commonly used solvents, their

Multiple sclerosis and organic solvents

DEFF Research Database (Denmark)

Mortensen, J T; Brønnum-Hansen, Henrik; Rasmussen, K

1998-01-01

We investigated a possible causal relation between exposure to organic solvents in Danish workers (housepainters, typographers/printers, carpenters/cabinetmakers) and onset of multiple sclerosis. Data on men included in the Danish Multiple Sclerosis Register (3,241 men) were linked with data from......, and butchers. Over a follow-up period of 20 years, we observed no increase in the incidence of multiple sclerosis among men presumed to be exposed to organic solvents. It was not possible to obtain data on potential confounders, and the study design has some potential for selection bias. Nevertheless......, the study does not support existing hypotheses regarding an association between occupational exposure to organic solvents and multiple sclerosis....

Performance of thermal solvent process in Athabasca reservoir

Energy Technology Data Exchange (ETDEWEB)

Das, Swapan [Marathon Oil (Canada)

2011-07-01

In the petroleum industry, due to depletion of conventional resources and high demand operators are looking into heavy oil and bitumen production. Different recovery methods exist, some of them based on heating the reservoir and others on the use of solvent. Thermal solvent process is a combination of both: a small amount of heat is used to maintain a solvent vapor phase in the reservoir. This process has advantages, solvent is mostly recycled which increases bitumen recovery efficiency and reduces the need for fresh solvent, but it also poses challenges, such as maintaining a vapor chamber and the fact that solvent solubility might be affected by heating. The aim of this paper is to discuss these issues. Simulations and field tests were conducted on bitumen in the the Athabasca region. This paper presented a thermal solvent process and its application's results in Athabasca reservoir.

Feasibility for the medium efficiency filter as a postfilter in the air cleaning unit

International Nuclear Information System (INIS)

Lim, H. S.; Jung, D. Y.; Byun, S. C.; Kim, S. H.

2002-01-01

The Air Cleaning Unit (ACU) is provided in a nuclear facility to filter the radioactive materials in gaseous effluents released from the facility during normal operation and during a postulated accident. The Air Cleaning Unit (ACU) consists of pre-HEPA filters, charcoal adsorber, post HEPA filters, fans, etc. The charcoal filters keep on-site dose and off-site effluents ALARA, consistent with regulatory requirements. The function of HEPA filter downstream of charcoal(carbon) adsorber in ACU is to catch potential radioactive carbon dust and to be a backup in the event of failure of upstream HEPA. Previous Regulatory Guide use only post HEPA filter of charcoal adsorber downstream but the Regulatory Guide of current revisions allows use of 95% dust spot efficiency filters in lieu of HEPA at the downstream of the carbon adsorber. In this paper is described that the background information of filters, Current Regulatory Guide of revised by the United States Nuclear Regulatory Commission and the feasibility for the medium efficiency filter as a carbon adsorber post filter in the Air Cleaning Unit

Apparatuses, Systems and Methods for Cleaning Photovoltaic Devices

KAUST Repository

Eitelhuber, Georg

2013-01-01

Embodiments of solar panel cleaning apparatuses, solar panel cleaning systems, and solar panel cleaning methods are disclosed. In certain embodiments, the disclosed solar panel cleaning apparatuses, systems and methods do may not require any water

Dry efficient cleaning of poly-methyl-methacrylate residues from graphene with high-density H{sub 2} and H{sub 2}-N{sub 2} plasmas

Energy Technology Data Exchange (ETDEWEB)

Cunge, G., E-mail: gilles.cunge@cea.fr; Petit-Etienne, C.; Davydova, A. [Laboratoire des Technologies de la Microélectronique, CNRS-UJF, 17 rue des Martyrs, 38054 Grenoble (France); Ferrah, D.; Renault, O. [CEA, LETI, MINATEC, 17 rue des Martyrs, 38054 Grenoble (France); Okuno, H. [CEA, INAC/SP2M/LEMMA, 17 rue des Martyrs, 38054 Grenoble (France); Kalita, D.; Bouchiat, V. [Institut Néel, CNRS-UJF-INP, BP 166, 38042 Grenoble Cedex 9 (France)

2015-09-28

Graphene is the first engineering electronic material, which is purely two-dimensional: it consists of two exposed sp{sup 2}-hybridized carbon surfaces and has no bulk. Therefore, surface effects such as contamination by adsorbed polymer residues have a critical influence on its electrical properties and can drastically hamper its widespread use in devices fabrication. These contaminants, originating from mandatory technological processes of graphene synthesis and transfer, also impact fundamental studies of the electronic and structural properties at the atomic scale. Therefore, graphene-based technology and research requires “soft” and selective surface cleaning techniques dedicated to limit or to suppress this surface contamination. Here, we show that a high-density H{sub 2} and H{sub 2}-N{sub 2} plasmas can be used to selectively remove polymeric residues from monolayer graphene without any damage on the graphene surface. The efficiency of this dry-cleaning process is evidenced unambiguously by a set of spectroscopic and microscopic methods, providing unprecedented insights on the cleaning mechanisms and highlighting the role of specific poly-methyl-methacrylate residues at the graphene interface. The plasma is shown to perform much better cleaning than solvents and has the advantage to be an industrially mature technology adapted to large area substrates. The process is transferable to other kinds of two-dimensional material and heterostructures.

Green solvents and technologies for oil extraction from oilseeds.

Science.gov (United States)

Kumar, S P Jeevan; Prasad, S Rajendra; Banerjee, Rintu; Agarwal, Dinesh K; Kulkarni, Kalyani S; Ramesh, K V

2017-01-01

Oilseeds are crucial for the nutritional security of the global population. The conventional technology used for oil extraction from oilseeds is by solvent extraction. In solvent extraction, n -hexane is used as a solvent for its attributes such as simple recovery, non-polar nature, low latent heat of vaporization (330 kJ/kg) and high selectivity to solvents. However, usage of hexane as a solvent has lead to several repercussions such as air pollution, toxicity and harmfulness that prompted to look for alternative options. To circumvent the problem, green solvents could be a promising approach to replace solvent extraction. In this review, green solvents and technology like aqueous assisted enzyme extraction are better solution for oil extraction from oilseeds. Enzyme mediated extraction is eco-friendly, can obtain higher yields, cost-effective and aids in obtaining co-products without any damage. Enzyme technology has great potential for oil extraction in oilseed industry. Similarly, green solvents such as terpenes and ionic liquids have tremendous solvent properties that enable to extract the oil in eco-friendly manner. These green solvents and technologies are considered green owing to the attributes of energy reduction, eco-friendliness, non-toxicity and non-harmfulness. Hence, the review is mainly focussed on the prospects and challenges of green solvents and technology as the best option to replace the conventional methods without compromising the quality of the extracted products.

Compound forming extractants, solvating solvents and inert solvents IUPAC chemical data series

CERN Document Server

Marcus, Y; Kertes, A S

2013-01-01

Equilibrium Constants of Liquid-Liquid Distribution Reactions, Part III: Compound Forming Extractants, Solvating Solvents, and Inert Solvents focuses on the compilation of equilibrium constants of various compounds, such as acids, ions, salts, and aqueous solutions. The manuscript presents tables that show the distribution reactions of carboxylic and sulfonic acid extractants and their dimerization and other reactions in the organic phase and extraction reactions of metal ions from aqueous solutions. The book also states that the inorganic anions in these solutions are irrelevant, since they d

Batch extracting process using magnetic particle held solvents

Science.gov (United States)

Nunez, L.; Vandergrift, G.F.

1995-11-21

A process is described for selectively removing metal values which may include catalytic values from a mixture containing same, wherein a magnetic particle is contacted with a liquid solvent which selectively dissolves the metal values to absorb the liquid solvent onto the magnetic particle. Thereafter the solvent-containing magnetic particles are contacted with a mixture containing the heavy metal values to transfer metal values into the solvent carried by the magnetic particles, and then magnetically separating the magnetic particles. Ion exchange resins may be used for selective solvents. 5 figs.

Recent Advances in Anhydrous Solvents for CO{sub 2} Capture: Ionic Liquids, Switchable Solvents, and Nanoparticle Organic Hybrid Materials

Energy Technology Data Exchange (ETDEWEB)

Park, Youngjune [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju (Korea, Republic of); Lin, Kun-Yi Andrew [Department of Environmental Engineering, National Chung Hsing University, Taichung City (China); Park, Ah-Hyung Alissa, E-mail: ap2622@columbia.edu [Department of Earth and Environmental Engineering, Lenfest Center for Sustainable Energy, Columbia University, New York, NY (United States); Department of Chemical Engineering, Lenfest Center for Sustainable Energy, Columbia University, New York, NY (United States); Petit, Camille, E-mail: ap2622@columbia.edu [Department of Chemical Engineering, Imperial College London, London (United Kingdom)

2015-10-01

CO{sub 2} capture by amine scrubbing, which has a high CO{sub 2} capture capacity and a rapid reaction rate, is the most employed and investigated approach to date. There are a number of recent large-scale demonstrations including the Boundary Dam Carbon Capture Project by SaskPower in Canada that have reported successful implementations of aqueous amine solvent in CO{sub 2} capture from flue gases. The findings from these demonstrations will significantly advance the field of CO{sub 2} capture in the coming years. While the latest efforts in aqueous amine solvents are exciting and promising, there are still several drawbacks to amine-based CO{sub 2} capture solvents including high volatility and corrosiveness of the amine solutions as well as the high parasitic energy penalty during the solvent regeneration step. Thus, in a parallel effort, alternative CO{sub 2} capture solvents, which are often anhydrous, have been developed as the third-generation CO{sub 2} capture solvents. These novel classes of liquid materials include ionic liquids, CO{sub 2}-triggered switchable solvents (i.e., CO{sub 2}-binding organic liquids, reversible ionic liquids), and nanoparticle organic hybrid materials. This paper provides a review of these various anhydrous solvents and their potential for CO{sub 2} capture. Particular attention is given to the mechanisms of CO{sub 2} absorption in these solvents, their regeneration and their processability – especially taking into account their viscosity. While not intended to provide a complete coverage of the existing literature, this review aims at pointing the major findings reported for these new classes of CO{sub 2} capture media.

Webinar: Green Cleaning for Improved Health: The Return on Investment of Green Cleaning in Schools

Science.gov (United States)

A page to register to view the June 22, 2017, webinar in the IAQ Knowledge-to-Action Professional Training Webinar Series: Green Cleaning for Improved Health: The Return on Investment of Green Cleaning in Schools

Fluoro-Carbonate Solvents for Li-Ion Cells

International Nuclear Information System (INIS)

NAGASUBRAMANIAN, GANESAN

1999-01-01

A number of fluoro-carbonate solvents were evaluated as electrolytes for Li-ion cells. These solvents are fluorine analogs of the conventional electrolyte solvents such as dimethyl carbonate, ethylene carbonate, diethyl carbonate in Li-ion cells. Conductivity of single and mixed fluoro carbonate electrolytes containing 1 M LiPF(sub 6) was measured at different temperatures. These electrolytes did not freeze at -40 C. We are evaluating currently, the irreversible 1st cycle capacity loss in carbon anode in these electrolytes and the capacity loss will be compared to that in the conventional electrolytes. Voltage stability windows of the electrolytes were measured at room temperature and compared with that of the conventional electrolytes. The fluoro-carbon electrolytes appear to be more stable than the conventional electrolytes near Li voltage. Few preliminary electrochemical data of the fluoro-carbonate solvents in full cells are reported in the literature. For example, some of the fluorocarbonate solvents appear to have a wider voltage window than the conventional electrolyte solvents. For example, methyl 2,2,2 trifluoro ethyl carbonate containing 1 M LiPF(sub 6) electrolyte has a decomposition voltage exceeding 6 V vs. Li compared to and lt;5 V for conventional electrolytes. The solvent also appears to be stable in contact with lithium at room temperature

Controlling Actinide Hydration in Mixed Solvent Systems: Towards Tunable Solvent Systems to Close the Fuel Cycle

International Nuclear Information System (INIS)

Clark, Sue B.

2016-01-01

The goal of this project has been to define the extent of hydration the f-elements and other cations in mixed solvent electrolyte systems. Methanol-water and other mixed solvent systems have been studied, where the solvent dielectric constant was varied systematically. Thermodynamic and spectroscopic studies provide details concerning the energetics of complexation and other reactions of these cations. This information has also been used to advance new understanding of the behavior of these cations in a variety of systems, ranging from environmental studies, chromatographic approaches, and ionization processes for mass spectrometry.

Controlling Actinide Hydration in Mixed Solvent Systems: Towards Tunable Solvent Systems to Close the Fuel Cycle

Energy Technology Data Exchange (ETDEWEB)

Clark, Sue B. [Washington State Univ., Pullman, WA (United States). Dept. of Chemistry

2016-10-31

The goal of this project has been to define the extent of hydration the f-elements and other cations in mixed solvent electrolyte systems. Methanol-water and other mixed solvent systems have been studied, where the solvent dielectric constant was varied systematically. Thermodynamic and spectroscopic studies provide details concerning the energetics of complexation and other reactions of these cations. This information has also been used to advance new understanding of the behavior of these cations in a variety of systems, ranging from environmental studies, chromatographic approaches, and ionization processes for mass spectrometry.

Tracking Clean Energy Progress 2013

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-06-01

Tracking Clean Energy Progress 2013 (TCEP 2013) examines progress in the development and deployment of key clean energy technologies. Each technology and sector is tracked against interim 2020 targets in the IEA Energy Technology Perspectives 2012 2°C scenario, which lays out pathways to a sustainable energy system in 2050. Stark message emerge: progress has not been fast enough; large market failures are preventing clean energy solutions from being taken up; considerable energy efficiency remains untapped; policies need to better address the energy system as a whole; and energy-related research, development and demonstration need to accelerate. Alongside these grim conclusions there is positive news. In 2012, hybrid-electric vehicle sales passed the 1 million mark. Solar photovoltaic systems were being installed at a record pace. The costs of most clean energy technologies fell more rapidly than anticipated.

Method of and apparatus for decontaminating radioactive garments

International Nuclear Information System (INIS)

Capella, J.A.; Morrison, D.R.

1980-01-01

Garments are deposited in a cleaning drum which is agitated during a wash cycle. A dry cleaning solvent is continuously added to the drum during the wash cycle and continuously removed from the drum during the wash cycle to flush the radioactive particulate material separated from the garments into a sump. The solvent is pumped from the sump for addition to the drum during the wash cycle and the pumped solvent is filtered to remove substantially all of the radioactive particulate material suspended in the solvent. Radiation sensors permit monitoring of the recycled solvent to ensure satisfactory operation of filters. The solvent is cleaned by a distilling apparatus, a condenser and a moisture separating apparatus. A fan dryer is provided. (author)

Clean energy, non-clean energy, and economic growth in the MIST countries

International Nuclear Information System (INIS)

Pao, Hsiao-Tien; Li, Yi-Ying; Hsin-Chia Fu

2014-01-01

This paper explores the causal relationship between clean (renewable/nuclear) and non-clean energy consumption and economic growth in emerging economies of the MIST (Mexico, Indonesia, South Korea, and Turkey) countries. The panel co-integration tests reveal that there is a long-term equilibrium relationship among GDP, capital formation, labor force, renewable/nuclear, and fossil fuel energy consumption. The panel causality results indicate that (1) there is a positive unidirectional short-run causality from fossil fuel energy consumption to economic growth with a bidirectional long-run causality; (2) there is a unidirectional long-run causality from renewable energy consumption to economic growth with positive bidirectional short-run causality, and a long-run causality from renewable to fossil fuel energy consumption with negative short-run feedback effects; and (3) there is a bidirectional long-run causality between nuclear energy consumption and economic growth and a long-run causality from fossil fuel energy consumption to nuclear energy consumption with positive short-run feedback effects. These suggest that MIST countries should be energy-dependent economies and that energy conservation policies may depress their economic development. However, developing renewable and nuclear energy is a viable solution for addressing energy security and climate change issues, and creating clean and fossil fuel energy partnerships could enhance a sustainable energy economy. - Highlights: • This novel study can provide more robust bases to strengthen sustainable energy policy settings. • Fossil fuel/nuclear energy use and economic growth is bidirectional causality. • Renewable energy consumption long term causes economic growth. • There is substitutability between renewable and fossil fuel energy. • Clean and non-clean energy partnerships can achieve a sustainable energy economy

Method of decomposing radioactive organic solvent wastes

International Nuclear Information System (INIS)

Uki, Kazuo; Ichihashi, Toshio; Hasegawa, Akira; Sato, Tatsuaki

1986-01-01

Purpose: To decompose radioactive organic solvent wastes or radioactive hydrocarbon solvents separated therefrom into organic materials under moderate conditions, as well as greatly decrease the amount of secondary wastes generated. Method: Radioactive organic solvent wastes comprising an organic phosphoric acid ester ingredient and a hydrocarbon ingredient as a diluent therefor, or radioactive hydrocarbon solvents separated therefrom are oxidatively decomposed by hydrogen peroxide in an aqueous phosphoric acid solution of phosphoric acid metal salts finally into organic materials to perform decomposing treatment for the radioactive organic solvent wastes. The decomposing reaction is carried out under relatively moderate conditions and cause less burden to facilities or the likes. Further, since the decomposed liquid after the treatment can be reused for the decomposing reaction as a catalyst solution secondary wastes can significantly be decreased. (Yoshihara, H.)

Problems of clean coals production as a sources of clean energy generation; Problemy produkcji czystych wegli jako zrodlo wytwarzania czystej energii

Energy Technology Data Exchange (ETDEWEB)

Blaschke, W. [Polish Academy of Sciences, Krakow (Poland). Mineral and Energy Economy Institute

2004-07-01

The paper advises of clean coal technology programme objectives. Issues connected with clean coals preparation for combustion have been discussed. The quality of steam fine coals has been presented, including those used in the commercial power industry. A small supply of 'clean coals' has been started in Poland, related however to a limited demand. Factors affecting the reduction in clean coal production have been discussed. The fact that there are no significant reasons to constrain supplies of clean coals has been emphasised. The quality of coal in deposits is very good, and the condition of preparation enables production of clean coal. Clean energy generation from clean coal requires only cooperation between the hard coal mining industry and the commercial power industry, passing over particular sectoral interests. 15 refs.

Permeability of commercial solvents through living human skin

DEFF Research Database (Denmark)

Ursin, C; Hansen, C M; Van Dyk, J W

1995-01-01

A procedure has been developed for measuring the steady state rate of permeation of commercial solvents through living human skin. To get the most consistent results, it was necessary with some solvents to normalize the solvent permeation rate of a given skin sample with its [3H]water permeation...... rate. For other solvents this was not necessary, so the un-normalized data were used. High [3H]water permeation rate also was used as a criterion for "defective" skin samples that gave erroneous permeability rates, especially for solvents having slow permeability. The linearity of the steady state data...... of DMSO and octyl acetate were measured. No octyl acetate was detected and the permeability of DMSO was proportional to its mole fraction in the mixture. The effect of two hours of solvent exposure on the viability of skin (based on DNA synthesis) was measured and found to be very dependent on the solvent....

Apparatuses, Systems and Methods for Cleaning Photovoltaic Devices

KAUST Repository

Eitelhuber, Georg

2013-02-14

Embodiments of solar panel cleaning apparatuses, solar panel cleaning systems, and solar panel cleaning methods are disclosed. In certain embodiments, the disclosed solar panel cleaning apparatuses, systems and methods do may not require any water or other cleaning liquids in the whole cleaning process, which makes them prominent well suited in for water-deficit environments such as deserts. In one embodiment, the solar panel cleaning apparatus comprises one or more rotatable brushes each having a rotational axis and a drive configured to move each of the one or more rotatable brushes in a direction that is not perpendicular to the rotational axis. The solar panel cleaning apparatus is may be configured such that the angle of the rotational axis of at least one of the one or more rotatable brushes is adjustable relative to the direction of travel.

Chlorinated solvents in groundwater of the United States

Science.gov (United States)

Moran, M.J.; Zogorski, J.S.; Squillace, P.J.

2007-01-01

Four chlorinated solvents-methylene chloride, perchloroethene (PCE), 1,1,1-trichloroethane, and trichloroethene (TCE)-were analyzed in samples of groundwater taken throughout the conterminous United States by the U.S. Geological Survey. The samples were collected between 1985 and 2002 from more than 5,000 wells. Of 55 volatile organic compounds (VOCs) analyzed in groundwater samples, solvents were among the most frequently detected. Mixtures of solvents in groundwater were common and may be the result of common usage of solvents or degradation of one solvent to another. Relative to other VOCs with Maximum Contaminant Levels (MCLs), PCE and TCE ranked high in terms of the frequencies of concentrations greater than or near MCLs. The probability of occurrence of solvents in groundwater was associated with dissolved oxygen content of groundwater, sources such as urban land use and population density, and hydraulic properties of the aquifer. The results reinforce the importance of understanding the redox conditions of aquifers and the hydraulic properties of the saturated and vadose zones in determining the intrinsic susceptibility of groundwater to contamination by solvents. The results also reinforce the importance of controlling sources of solvents to groundwater. ?? 2007 American Chemical Society.

Next Generation Solvent - Materials Compatibility With Polymer Components Within Modular Caustic-Side Solvent Extraction Unit (Final Report)

International Nuclear Information System (INIS)

Fondeur, F.; Peters, T.; Fink, S.

2012-01-01

The Office of Waste Processing, within the Office of Technology Innovation and Development, is funding the development of an enhanced solvent for deployment at the Savannah River Site for removal of cesium from High Level Waste. The technical effort is collaboration between Oak Ridge National Laboratory (ORNL), Savannah River National Laboratory (SRNL), and Argonne National Laboratory. The first deployment target for the technology is within the Modular Caustic-Side Solvent Extraction Unit (MCU). Deployment of a new chemical within an existing facility requires verification that the chemical components are compatible with the installed equipment. In the instance of a new organic solvent, the primary focus is on compatibility of the solvent with organic polymers used in the facility. This report provides the data from exposing these polymers to the Next Generation Solvent (NGS). The test was conducted over six months. An assessment of the dimensional stability of polymers present in MCU (i.e., PEEK, Grafoil, Tefzel and Isolast) in the modified NGS (where the concentration of LIX(reg s ign)79 and MaxCalix was varied systematically) showed that LIX(reg s ign)79 selectively affected Tefzel and its different grades (by an increase in size and lowering its density). The copolymer structure of Tefzel and possibly its porosity allows for the easier diffusion of LIX(reg s ign)79. Tefzel is used as the seat material in some of the valves at MCU. Long term exposure to LIX(reg s ign)79, may make the valves hard to operate over time due to the seat material (Tefzel) increasing in size. However, since the physical changes of Tefzel in the improved solvent are comparable to the changes in the CSSX baseline solvent, no design changes are needed with respect to the Tefzel seating material. PEEK, Grafoil and Isolast were not affected by LIX(reg s ign)79 and MaxCalix within six months of exposure. The initial rapid weight gain observed in every polymer is assigned to the finite and

NEXT GENERATION SOLVENT-MATERIALS COMPATIBILITY WITH POLYMER COMPONENTS WITHIN MODULAR CAUSTIC-SIDE SOLVENT EXTRACTION UNIT (FINAL REPORT)

Energy Technology Data Exchange (ETDEWEB)

Fondeur, F.; Peters, T.; Fink, S.

2012-01-17

The Office of Waste Processing, within the Office of Technology Innovation and Development, is funding the development of an enhanced solvent for deployment at the Savannah River Site for removal of cesium from High Level Waste. The technical effort is collaboration between Oak Ridge National Laboratory (ORNL), Savannah River National Laboratory (SRNL), and Argonne National Laboratory. The first deployment target for the technology is within the Modular Caustic-Side Solvent Extraction Unit (MCU). Deployment of a new chemical within an existing facility requires verification that the chemical components are compatible with the installed equipment. In the instance of a new organic solvent, the primary focus is on compatibility of the solvent with organic polymers used in the facility. This report provides the data from exposing these polymers to the Next Generation Solvent (NGS). The test was conducted over six months. An assessment of the dimensional stability of polymers present in MCU (i.e., PEEK, Grafoil, Tefzel and Isolast) in the modified NGS (where the concentration of LIX{reg_sign}79 and MaxCalix was varied systematically) showed that LIX{reg_sign}79 selectively affected Tefzel and its different grades (by an increase in size and lowering its density). The copolymer structure of Tefzel and possibly its porosity allows for the easier diffusion of LIX{reg_sign}79. Tefzel is used as the seat material in some of the valves at MCU. Long term exposure to LIX{reg_sign}79, may make the valves hard to operate over time due to the seat material (Tefzel) increasing in size. However, since the physical changes of Tefzel in the improved solvent are comparable to the changes in the CSSX baseline solvent, no design changes are needed with respect to the Tefzel seating material. PEEK, Grafoil and Isolast were not affected by LIX{reg_sign}79 and MaxCalix within six months of exposure. The initial rapid weight gain observed in every polymer is assigned to the finite and

Assessment of poly(ε-caprolactone)/poly(3-hydroxybutyrate-co-3-hydroxyvalerate) blends processed by solvent casting and electrospinning

International Nuclear Information System (INIS)

Del Gaudio, Costantino; Ercolani, Enrico; Nanni, Francesca; Bianco, Alessandra

2011-01-01

Research highlights: → PHBV, PCL and blends were processed in form of solvent cast films and e-spun mats. → A clear phase separation was observed for cast films when blended in equal amount. → E-spun blends were comprised of uniform and defect-free randomly arranged fibers. → DSC and XRD analyses demonstrated the immiscibility of PHBV and PCL. → Rearrangement of e-spun fibers and neckings, after axial test, were observed. - Abstract: Poly(ε-caprolactone) (PCL) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were blended in different ratio, e.g. 30/70, 50/50 and 70/30 (w/w), by means of solvent casting or electrospinning. Microstructure, thermal and mechanical properties of cast films and non-woven mats were investigated by means of scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), differential scanning calorimetry (DSC), and uniaxial tensile test. The microstructure of PHBV/PCL solvent cast films (thickness 65-100 μm) was strictly dependent on the composition of the blend, a clean phase separation was observed for the 50/50 (w/w) sample. All electrospun PHBV/PCL blends (thickness 350-800 μm) were characterised by uniform and homogenous fibers, the average size was about 3 μm. Both techniques led to polymeric blends comprised of separate crystalline domains associated to an amorphous interdisperse phase. It has also been demonstrated that electrospun PHBV/PCL blends showed a lower segregation degree among the crystalline domains. Solvent cast blends were characterised by superior mechanical properties in terms of tensile modulus and tensile strength compared to electrospun ones. Fractured electrospun blends showed an overall fiber rearrangement in the direction of the applied load, eventually highlighting multiple necking regions along the fibers.